1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright 2019 Joyent, Inc.
25 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
26 */
27
28 /*
29 * DTrace - Dynamic Tracing for Solaris
30 *
31 * This is the implementation of the Solaris Dynamic Tracing framework
32 * (DTrace). The user-visible interface to DTrace is described at length in
33 * the "Solaris Dynamic Tracing Guide". The interfaces between the libdtrace
34 * library, the in-kernel DTrace framework, and the DTrace providers are
35 * described in the block comments in the <sys/dtrace.h> header file. The
36 * internal architecture of DTrace is described in the block comments in the
37 * <sys/dtrace_impl.h> header file. The comments contained within the DTrace
38 * implementation very much assume mastery of all of these sources; if one has
39 * an unanswered question about the implementation, one should consult them
40 * first.
41 *
42 * The functions here are ordered roughly as follows:
43 *
44 * - Probe context functions
45 * - Probe hashing functions
46 * - Non-probe context utility functions
47 * - Matching functions
48 * - Provider-to-Framework API functions
49 * - Probe management functions
50 * - DIF object functions
51 * - Format functions
52 * - Predicate functions
53 * - ECB functions
54 * - Buffer functions
55 * - Enabling functions
56 * - DOF functions
57 * - Anonymous enabling functions
58 * - Consumer state functions
59 * - Helper functions
60 * - Hook functions
61 * - Driver cookbook functions
62 *
63 * Each group of functions begins with a block comment labelled the "DTrace
64 * [Group] Functions", allowing one to find each block by searching forward
65 * on capital-f functions.
66 */
67 #include <sys/errno.h>
68 #include <sys/stat.h>
69 #include <sys/modctl.h>
70 #include <sys/conf.h>
71 #include <sys/systm.h>
72 #include <sys/ddi.h>
73 #include <sys/sunddi.h>
74 #include <sys/cpuvar.h>
75 #include <sys/kmem.h>
76 #include <sys/strsubr.h>
77 #include <sys/sysmacros.h>
78 #include <sys/dtrace_impl.h>
79 #include <sys/atomic.h>
80 #include <sys/cmn_err.h>
81 #include <sys/mutex_impl.h>
82 #include <sys/rwlock_impl.h>
83 #include <sys/ctf_api.h>
84 #include <sys/panic.h>
85 #include <sys/priv_impl.h>
86 #include <sys/policy.h>
87 #include <sys/cred_impl.h>
88 #include <sys/procfs_isa.h>
89 #include <sys/taskq.h>
90 #include <sys/mkdev.h>
91 #include <sys/kdi.h>
92 #include <sys/zone.h>
93 #include <sys/socket.h>
94 #include <netinet/in.h>
95 #include "strtolctype.h"
96
97 /*
98 * DTrace Tunable Variables
99 *
100 * The following variables may be tuned by adding a line to /etc/system that
101 * includes both the name of the DTrace module ("dtrace") and the name of the
102 * variable. For example:
103 *
104 * set dtrace:dtrace_destructive_disallow = 1
105 *
106 * In general, the only variables that one should be tuning this way are those
107 * that affect system-wide DTrace behavior, and for which the default behavior
108 * is undesirable. Most of these variables are tunable on a per-consumer
109 * basis using DTrace options, and need not be tuned on a system-wide basis.
110 * When tuning these variables, avoid pathological values; while some attempt
111 * is made to verify the integrity of these variables, they are not considered
112 * part of the supported interface to DTrace, and they are therefore not
113 * checked comprehensively. Further, these variables should not be tuned
114 * dynamically via "mdb -kw" or other means; they should only be tuned via
115 * /etc/system.
116 */
117 int dtrace_destructive_disallow = 0;
118 dtrace_optval_t dtrace_nonroot_maxsize = (16 * 1024 * 1024);
119 size_t dtrace_difo_maxsize = (256 * 1024);
120 dtrace_optval_t dtrace_dof_maxsize = (8 * 1024 * 1024);
121 size_t dtrace_statvar_maxsize = (16 * 1024);
122 size_t dtrace_actions_max = (16 * 1024);
123 size_t dtrace_retain_max = 1024;
124 dtrace_optval_t dtrace_helper_actions_max = 1024;
125 dtrace_optval_t dtrace_helper_providers_max = 32;
126 dtrace_optval_t dtrace_dstate_defsize = (1 * 1024 * 1024);
127 size_t dtrace_strsize_default = 256;
128 dtrace_optval_t dtrace_cleanrate_default = 9900990; /* 101 hz */
129 dtrace_optval_t dtrace_cleanrate_min = 200000; /* 5000 hz */
130 dtrace_optval_t dtrace_cleanrate_max = (uint64_t)60 * NANOSEC; /* 1/minute */
131 dtrace_optval_t dtrace_aggrate_default = NANOSEC; /* 1 hz */
132 dtrace_optval_t dtrace_statusrate_default = NANOSEC; /* 1 hz */
133 dtrace_optval_t dtrace_statusrate_max = (hrtime_t)10 * NANOSEC; /* 6/minute */
134 dtrace_optval_t dtrace_switchrate_default = NANOSEC; /* 1 hz */
135 dtrace_optval_t dtrace_nspec_default = 1;
136 dtrace_optval_t dtrace_specsize_default = 32 * 1024;
137 dtrace_optval_t dtrace_stackframes_default = 20;
138 dtrace_optval_t dtrace_ustackframes_default = 20;
139 dtrace_optval_t dtrace_jstackframes_default = 50;
140 dtrace_optval_t dtrace_jstackstrsize_default = 512;
141 int dtrace_msgdsize_max = 128;
142 hrtime_t dtrace_chill_max = MSEC2NSEC(500); /* 500 ms */
143 hrtime_t dtrace_chill_interval = NANOSEC; /* 1000 ms */
144 int dtrace_devdepth_max = 32;
145 int dtrace_err_verbose;
146 hrtime_t dtrace_deadman_interval = NANOSEC;
147 hrtime_t dtrace_deadman_timeout = (hrtime_t)10 * NANOSEC;
148 hrtime_t dtrace_deadman_user = (hrtime_t)30 * NANOSEC;
149 hrtime_t dtrace_unregister_defunct_reap = (hrtime_t)60 * NANOSEC;
150
151 /*
152 * DTrace External Variables
153 *
154 * As dtrace(7D) is a kernel module, any DTrace variables are obviously
155 * available to DTrace consumers via the backtick (`) syntax. One of these,
156 * dtrace_zero, is made deliberately so: it is provided as a source of
157 * well-known, zero-filled memory. While this variable is not documented,
158 * it is used by some translators as an implementation detail.
159 */
160 const char dtrace_zero[256] = { 0 }; /* zero-filled memory */
161
162 /*
163 * DTrace Internal Variables
164 */
165 static dev_info_t *dtrace_devi; /* device info */
166 static vmem_t *dtrace_arena; /* probe ID arena */
167 static vmem_t *dtrace_minor; /* minor number arena */
168 static taskq_t *dtrace_taskq; /* task queue */
169 static dtrace_probe_t **dtrace_probes; /* array of all probes */
170 static int dtrace_nprobes; /* number of probes */
171 static dtrace_provider_t *dtrace_provider; /* provider list */
172 static dtrace_meta_t *dtrace_meta_pid; /* user-land meta provider */
173 static int dtrace_opens; /* number of opens */
174 static int dtrace_helpers; /* number of helpers */
175 static int dtrace_getf; /* number of unpriv getf()s */
176 static void *dtrace_softstate; /* softstate pointer */
177 static dtrace_hash_t *dtrace_bymod; /* probes hashed by module */
178 static dtrace_hash_t *dtrace_byfunc; /* probes hashed by function */
179 static dtrace_hash_t *dtrace_byname; /* probes hashed by name */
180 static dtrace_toxrange_t *dtrace_toxrange; /* toxic range array */
181 static int dtrace_toxranges; /* number of toxic ranges */
182 static int dtrace_toxranges_max; /* size of toxic range array */
183 static dtrace_anon_t dtrace_anon; /* anonymous enabling */
184 static kmem_cache_t *dtrace_state_cache; /* cache for dynamic state */
185 static uint64_t dtrace_vtime_references; /* number of vtimestamp refs */
186 static kthread_t *dtrace_panicked; /* panicking thread */
187 static dtrace_ecb_t *dtrace_ecb_create_cache; /* cached created ECB */
188 static dtrace_genid_t dtrace_probegen; /* current probe generation */
189 static dtrace_helpers_t *dtrace_deferred_pid; /* deferred helper list */
190 static dtrace_enabling_t *dtrace_retained; /* list of retained enablings */
191 static dtrace_genid_t dtrace_retained_gen; /* current retained enab gen */
192 static dtrace_dynvar_t dtrace_dynhash_sink; /* end of dynamic hash chains */
193 static int dtrace_dynvar_failclean; /* dynvars failed to clean */
194
195 /*
196 * DTrace Locking
197 * DTrace is protected by three (relatively coarse-grained) locks:
198 *
199 * (1) dtrace_lock is required to manipulate essentially any DTrace state,
200 * including enabling state, probes, ECBs, consumer state, helper state,
201 * etc. Importantly, dtrace_lock is _not_ required when in probe context;
202 * probe context is lock-free -- synchronization is handled via the
203 * dtrace_sync() cross call mechanism.
204 *
205 * (2) dtrace_provider_lock is required when manipulating provider state, or
206 * when provider state must be held constant.
207 *
208 * (3) dtrace_meta_lock is required when manipulating meta provider state, or
209 * when meta provider state must be held constant.
210 *
211 * The lock ordering between these three locks is dtrace_meta_lock before
212 * dtrace_provider_lock before dtrace_lock. (In particular, there are
213 * several places where dtrace_provider_lock is held by the framework as it
214 * calls into the providers -- which then call back into the framework,
215 * grabbing dtrace_lock.)
216 *
217 * There are two other locks in the mix: mod_lock and cpu_lock. With respect
218 * to dtrace_provider_lock and dtrace_lock, cpu_lock continues its historical
219 * role as a coarse-grained lock; it is acquired before both of these locks.
220 * With respect to dtrace_meta_lock, its behavior is stranger: cpu_lock must
221 * be acquired _between_ dtrace_meta_lock and any other DTrace locks.
222 * mod_lock is similar with respect to dtrace_provider_lock in that it must be
223 * acquired _between_ dtrace_provider_lock and dtrace_lock.
224 */
225 static kmutex_t dtrace_lock; /* probe state lock */
226 static kmutex_t dtrace_provider_lock; /* provider state lock */
227 static kmutex_t dtrace_meta_lock; /* meta-provider state lock */
228
229 /*
230 * DTrace Provider Variables
231 *
232 * These are the variables relating to DTrace as a provider (that is, the
233 * provider of the BEGIN, END, and ERROR probes).
234 */
235 static dtrace_pattr_t dtrace_provider_attr = {
236 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
237 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
238 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
239 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
240 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
241 };
242
243 static void
244 dtrace_nullop_provide(void *arg __unused,
245 const dtrace_probedesc_t *spec __unused)
246 {
247 }
248
249 static void
250 dtrace_nullop_module(void *arg __unused, struct modctl *mp __unused)
251 {
252 }
253
254 static void
255 dtrace_nullop(void *arg __unused, dtrace_id_t id __unused, void *parg __unused)
256 {
257 }
258
259 static int
260 dtrace_enable_nullop(void *arg __unused, dtrace_id_t id __unused,
261 void *parg __unused)
262 {
263 return (0);
264 }
265
266 static dtrace_pops_t dtrace_provider_ops = {
267 .dtps_provide = dtrace_nullop_provide,
268 .dtps_provide_module = dtrace_nullop_module,
269 .dtps_enable = dtrace_enable_nullop,
270 .dtps_disable = dtrace_nullop,
271 .dtps_suspend = dtrace_nullop,
272 .dtps_resume = dtrace_nullop,
273 .dtps_getargdesc = NULL,
274 .dtps_getargval = NULL,
275 .dtps_mode = NULL,
276 .dtps_destroy = dtrace_nullop
277 };
278
279 static dtrace_id_t dtrace_probeid_begin; /* special BEGIN probe */
280 static dtrace_id_t dtrace_probeid_end; /* special END probe */
281 dtrace_id_t dtrace_probeid_error; /* special ERROR probe */
282
283 /*
284 * DTrace Helper Tracing Variables
285 *
286 * These variables should be set dynamically to enable helper tracing. The
287 * only variables that should be set are dtrace_helptrace_enable (which should
288 * be set to a non-zero value to allocate helper tracing buffers on the next
289 * open of /dev/dtrace) and dtrace_helptrace_disable (which should be set to a
290 * non-zero value to deallocate helper tracing buffers on the next close of
291 * /dev/dtrace). When (and only when) helper tracing is disabled, the
292 * buffer size may also be set via dtrace_helptrace_bufsize.
293 */
294 int dtrace_helptrace_enable = 0;
295 int dtrace_helptrace_disable = 0;
296 int dtrace_helptrace_bufsize = 16 * 1024 * 1024;
297 uint32_t dtrace_helptrace_nlocals;
298 static dtrace_helptrace_t *dtrace_helptrace_buffer;
299 static uint32_t dtrace_helptrace_next = 0;
300 static int dtrace_helptrace_wrapped = 0;
301
302 /*
303 * DTrace Error Hashing
304 *
305 * On DEBUG kernels, DTrace will track the errors that has seen in a hash
306 * table. This is very useful for checking coverage of tests that are
307 * expected to induce DIF or DOF processing errors, and may be useful for
308 * debugging problems in the DIF code generator or in DOF generation . The
309 * error hash may be examined with the ::dtrace_errhash MDB dcmd.
310 */
311 #ifdef DEBUG
312 static dtrace_errhash_t dtrace_errhash[DTRACE_ERRHASHSZ];
313 static const char *dtrace_errlast;
314 static kthread_t *dtrace_errthread;
315 static kmutex_t dtrace_errlock;
316 #endif
317
318 /*
319 * DTrace Macros and Constants
320 *
321 * These are various macros that are useful in various spots in the
322 * implementation, along with a few random constants that have no meaning
323 * outside of the implementation. There is no real structure to this cpp
324 * mishmash -- but is there ever?
325 */
326 #define DTRACE_HASHSTR(hash, probe) \
327 dtrace_hash_str(*((char **)((uintptr_t)(probe) + (hash)->dth_stroffs)))
328
329 #define DTRACE_HASHNEXT(hash, probe) \
330 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_nextoffs)
331
332 #define DTRACE_HASHPREV(hash, probe) \
333 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_prevoffs)
334
335 #define DTRACE_HASHEQ(hash, lhs, rhs) \
336 (strcmp(*((char **)((uintptr_t)(lhs) + (hash)->dth_stroffs)), \
337 *((char **)((uintptr_t)(rhs) + (hash)->dth_stroffs))) == 0)
338
339 #define DTRACE_AGGHASHSIZE_SLEW 17
340
341 #define DTRACE_V4MAPPED_OFFSET (sizeof (uint32_t) * 3)
342
343 /*
344 * The key for a thread-local variable consists of the lower 61 bits of the
345 * t_did, plus the 3 bits of the highest active interrupt above LOCK_LEVEL.
346 * We add DIF_VARIABLE_MAX to t_did to assure that the thread key is never
347 * equal to a variable identifier. This is necessary (but not sufficient) to
348 * assure that global associative arrays never collide with thread-local
349 * variables. To guarantee that they cannot collide, we must also define the
350 * order for keying dynamic variables. That order is:
351 *
352 * [ key0 ] ... [ keyn ] [ variable-key ] [ tls-key ]
353 *
354 * Because the variable-key and the tls-key are in orthogonal spaces, there is
355 * no way for a global variable key signature to match a thread-local key
356 * signature.
357 */
358 #define DTRACE_TLS_THRKEY(where) { \
359 uint_t intr = 0; \
360 uint_t actv = CPU->cpu_intr_actv >> (LOCK_LEVEL + 1); \
361 for (; actv; actv >>= 1) \
362 intr++; \
363 ASSERT(intr < (1 << 3)); \
364 (where) = ((curthread->t_did + DIF_VARIABLE_MAX) & \
365 (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \
366 }
367
368 #define DT_BSWAP_8(x) ((x) & 0xff)
369 #define DT_BSWAP_16(x) ((DT_BSWAP_8(x) << 8) | DT_BSWAP_8((x) >> 8))
370 #define DT_BSWAP_32(x) ((DT_BSWAP_16(x) << 16) | DT_BSWAP_16((x) >> 16))
371 #define DT_BSWAP_64(x) ((DT_BSWAP_32(x) << 32) | DT_BSWAP_32((x) >> 32))
372
373 #define DT_MASK_LO 0x00000000FFFFFFFFULL
374
375 #define DTRACE_STORE(type, tomax, offset, what) \
376 *((type *)((uintptr_t)(tomax) + (uintptr_t)offset)) = (type)(what);
377
378 #ifndef __x86
379 #define DTRACE_ALIGNCHECK(addr, size, flags) \
380 if (addr & (size - 1)) { \
381 *flags |= CPU_DTRACE_BADALIGN; \
382 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
383 return (0); \
384 }
385 #else
386 #define DTRACE_ALIGNCHECK(addr, size, flags)
387 #endif
388
389 /*
390 * Test whether a range of memory starting at testaddr of size testsz falls
391 * within the range of memory described by addr, sz. We take care to avoid
392 * problems with overflow and underflow of the unsigned quantities, and
393 * disallow all negative sizes. Ranges of size 0 are allowed.
394 */
395 #define DTRACE_INRANGE(testaddr, testsz, baseaddr, basesz) \
396 ((testaddr) - (uintptr_t)(baseaddr) < (basesz) && \
397 (testaddr) + (testsz) - (uintptr_t)(baseaddr) <= (basesz) && \
398 (testaddr) + (testsz) >= (testaddr))
399
400 #define DTRACE_RANGE_REMAIN(remp, addr, baseaddr, basesz) \
401 do { \
402 if ((remp) != NULL) { \
403 *(remp) = (uintptr_t)(baseaddr) + (basesz) - (addr); \
404 } \
405 _NOTE(CONSTCOND) } while (0)
406
407
408 /*
409 * Test whether alloc_sz bytes will fit in the scratch region. We isolate
410 * alloc_sz on the righthand side of the comparison in order to avoid overflow
411 * or underflow in the comparison with it. This is simpler than the INRANGE
412 * check above, because we know that the dtms_scratch_ptr is valid in the
413 * range. Allocations of size zero are allowed.
414 */
415 #define DTRACE_INSCRATCH(mstate, alloc_sz) \
416 ((mstate)->dtms_scratch_base + (mstate)->dtms_scratch_size - \
417 (mstate)->dtms_scratch_ptr >= (alloc_sz))
418
419 #define DTRACE_LOADFUNC(bits) \
420 /*CSTYLED*/ \
421 uint##bits##_t \
422 dtrace_load##bits(uintptr_t addr) \
423 { \
424 size_t size = bits / NBBY; \
425 /*CSTYLED*/ \
426 uint##bits##_t rval; \
427 int i; \
428 volatile uint16_t *flags = (volatile uint16_t *) \
429 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; \
430 \
431 DTRACE_ALIGNCHECK(addr, size, flags); \
432 \
433 for (i = 0; i < dtrace_toxranges; i++) { \
434 if (addr >= dtrace_toxrange[i].dtt_limit) \
435 continue; \
436 \
437 if (addr + size <= dtrace_toxrange[i].dtt_base) \
438 continue; \
439 \
440 /* \
441 * This address falls within a toxic region; return 0. \
442 */ \
443 *flags |= CPU_DTRACE_BADADDR; \
444 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
445 return (0); \
446 } \
447 \
448 *flags |= CPU_DTRACE_NOFAULT; \
449 /*CSTYLED*/ \
450 rval = *((volatile uint##bits##_t *)addr); \
451 *flags &= ~CPU_DTRACE_NOFAULT; \
452 \
453 return (!(*flags & CPU_DTRACE_FAULT) ? rval : 0); \
454 }
455
456 #ifdef _LP64
457 #define dtrace_loadptr dtrace_load64
458 #else
459 #define dtrace_loadptr dtrace_load32
460 #endif
461
462 #define DTRACE_DYNHASH_FREE 0
463 #define DTRACE_DYNHASH_SINK 1
464 #define DTRACE_DYNHASH_VALID 2
465
466 #define DTRACE_MATCH_FAIL -1
467 #define DTRACE_MATCH_NEXT 0
468 #define DTRACE_MATCH_DONE 1
469 #define DTRACE_ANCHORED(probe) ((probe)->dtpr_func[0] != '\0')
470 #define DTRACE_STATE_ALIGN 64
471
472 #define DTRACE_FLAGS2FLT(flags) \
473 (((flags) & CPU_DTRACE_BADADDR) ? DTRACEFLT_BADADDR : \
474 ((flags) & CPU_DTRACE_ILLOP) ? DTRACEFLT_ILLOP : \
475 ((flags) & CPU_DTRACE_DIVZERO) ? DTRACEFLT_DIVZERO : \
476 ((flags) & CPU_DTRACE_KPRIV) ? DTRACEFLT_KPRIV : \
477 ((flags) & CPU_DTRACE_UPRIV) ? DTRACEFLT_UPRIV : \
478 ((flags) & CPU_DTRACE_TUPOFLOW) ? DTRACEFLT_TUPOFLOW : \
479 ((flags) & CPU_DTRACE_BADALIGN) ? DTRACEFLT_BADALIGN : \
480 ((flags) & CPU_DTRACE_NOSCRATCH) ? DTRACEFLT_NOSCRATCH : \
481 ((flags) & CPU_DTRACE_BADSTACK) ? DTRACEFLT_BADSTACK : \
482 DTRACEFLT_UNKNOWN)
483
484 #define DTRACEACT_ISSTRING(act) \
485 ((act)->dta_kind == DTRACEACT_DIFEXPR && \
486 (act)->dta_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING)
487
488 static size_t dtrace_strlen(const char *, size_t);
489 static dtrace_probe_t *dtrace_probe_lookup_id(dtrace_id_t id);
490 static void dtrace_enabling_provide(dtrace_provider_t *);
491 static int dtrace_enabling_match(dtrace_enabling_t *, int *);
492 static void dtrace_enabling_matchall(void);
493 static void dtrace_enabling_reap(void);
494 static dtrace_state_t *dtrace_anon_grab(void);
495 static uint64_t dtrace_helper(int, dtrace_mstate_t *,
496 dtrace_state_t *, uint64_t, uint64_t);
497 static dtrace_helpers_t *dtrace_helpers_create(proc_t *);
498 static void dtrace_buffer_drop(dtrace_buffer_t *);
499 static int dtrace_buffer_consumed(dtrace_buffer_t *, hrtime_t when);
500 static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *, size_t, size_t,
501 dtrace_state_t *, dtrace_mstate_t *);
502 static int dtrace_state_option(dtrace_state_t *, dtrace_optid_t,
503 dtrace_optval_t);
504 static int dtrace_ecb_create_enable(dtrace_probe_t *, void *);
505 static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *);
506 static int dtrace_priv_proc(dtrace_state_t *, dtrace_mstate_t *);
507 static void dtrace_getf_barrier(void);
508 static int dtrace_canload_remains(uint64_t, size_t, size_t *,
509 dtrace_mstate_t *, dtrace_vstate_t *);
510 static int dtrace_canstore_remains(uint64_t, size_t, size_t *,
511 dtrace_mstate_t *, dtrace_vstate_t *);
512
513 /*
514 * DTrace Probe Context Functions
515 *
516 * These functions are called from probe context. Because probe context is
517 * any context in which C may be called, arbitrarily locks may be held,
518 * interrupts may be disabled, we may be in arbitrary dispatched state, etc.
519 * As a result, functions called from probe context may only call other DTrace
520 * support functions -- they may not interact at all with the system at large.
521 * (Note that the ASSERT macro is made probe-context safe by redefining it in
522 * terms of dtrace_assfail(), a probe-context safe function.) If arbitrary
523 * loads are to be performed from probe context, they _must_ be in terms of
524 * the safe dtrace_load*() variants.
525 *
526 * Some functions in this block are not actually called from probe context;
527 * for these functions, there will be a comment above the function reading
528 * "Note: not called from probe context."
529 */
530 void
531 dtrace_panic(const char *format, ...)
532 {
533 va_list alist;
534
535 va_start(alist, format);
536 dtrace_vpanic(format, alist);
537 va_end(alist);
538 }
539
540 int
541 dtrace_assfail(const char *a, const char *f, int l)
542 {
543 dtrace_panic("assertion failed: %s, file: %s, line: %d", a, f, l);
544
545 /*
546 * We just need something here that even the most clever compiler
547 * cannot optimize away.
548 */
549 return (a[(uintptr_t)f]);
550 }
551
552 /*
553 * Atomically increment a specified error counter from probe context.
554 */
555 static void
556 dtrace_error(uint32_t *counter)
557 {
558 /*
559 * Most counters stored to in probe context are per-CPU counters.
560 * However, there are some error conditions that are sufficiently
561 * arcane that they don't merit per-CPU storage. If these counters
562 * are incremented concurrently on different CPUs, scalability will be
563 * adversely affected -- but we don't expect them to be white-hot in a
564 * correctly constructed enabling...
565 */
566 uint32_t oval, nval;
567
568 do {
569 oval = *counter;
570
571 if ((nval = oval + 1) == 0) {
572 /*
573 * If the counter would wrap, set it to 1 -- assuring
574 * that the counter is never zero when we have seen
575 * errors. (The counter must be 32-bits because we
576 * aren't guaranteed a 64-bit compare&swap operation.)
577 * To save this code both the infamy of being fingered
578 * by a priggish news story and the indignity of being
579 * the target of a neo-puritan witch trial, we're
580 * carefully avoiding any colorful description of the
581 * likelihood of this condition -- but suffice it to
582 * say that it is only slightly more likely than the
583 * overflow of predicate cache IDs, as discussed in
584 * dtrace_predicate_create().
585 */
586 nval = 1;
587 }
588 } while (dtrace_cas32(counter, oval, nval) != oval);
589 }
590
591 /*
592 * Use the DTRACE_LOADFUNC macro to define functions for each of loading a
593 * uint8_t, a uint16_t, a uint32_t and a uint64_t.
594 */
595 /* BEGIN CSTYLED */
596 DTRACE_LOADFUNC(8)
597 DTRACE_LOADFUNC(16)
598 DTRACE_LOADFUNC(32)
599 DTRACE_LOADFUNC(64)
600 /* END CSTYLED */
601
602 static int
603 dtrace_inscratch(uintptr_t dest, size_t size, dtrace_mstate_t *mstate)
604 {
605 if (dest < mstate->dtms_scratch_base)
606 return (0);
607
608 if (dest + size < dest)
609 return (0);
610
611 if (dest + size > mstate->dtms_scratch_ptr)
612 return (0);
613
614 return (1);
615 }
616
617 static int
618 dtrace_canstore_statvar(uint64_t addr, size_t sz, size_t *remain,
619 dtrace_statvar_t **svars, int nsvars)
620 {
621 int i;
622 size_t maxglobalsize, maxlocalsize;
623
624 if (nsvars == 0)
625 return (0);
626
627 maxglobalsize = dtrace_statvar_maxsize + sizeof (uint64_t);
628 maxlocalsize = maxglobalsize * NCPU;
629
630 for (i = 0; i < nsvars; i++) {
631 dtrace_statvar_t *svar = svars[i];
632 uint8_t scope;
633 size_t size;
634
635 if (svar == NULL || (size = svar->dtsv_size) == 0)
636 continue;
637
638 scope = svar->dtsv_var.dtdv_scope;
639
640 /*
641 * We verify that our size is valid in the spirit of providing
642 * defense in depth: we want to prevent attackers from using
643 * DTrace to escalate an orthogonal kernel heap corruption bug
644 * into the ability to store to arbitrary locations in memory.
645 */
646 VERIFY((scope == DIFV_SCOPE_GLOBAL && size <= maxglobalsize) ||
647 (scope == DIFV_SCOPE_LOCAL && size <= maxlocalsize));
648
649 if (DTRACE_INRANGE(addr, sz, svar->dtsv_data,
650 svar->dtsv_size)) {
651 DTRACE_RANGE_REMAIN(remain, addr, svar->dtsv_data,
652 svar->dtsv_size);
653 return (1);
654 }
655 }
656
657 return (0);
658 }
659
660 /*
661 * Check to see if the address is within a memory region to which a store may
662 * be issued. This includes the DTrace scratch areas, and any DTrace variable
663 * region. The caller of dtrace_canstore() is responsible for performing any
664 * alignment checks that are needed before stores are actually executed.
665 */
666 static int
667 dtrace_canstore(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
668 dtrace_vstate_t *vstate)
669 {
670 return (dtrace_canstore_remains(addr, sz, NULL, mstate, vstate));
671 }
672
673 /*
674 * Implementation of dtrace_canstore which communicates the upper bound of the
675 * allowed memory region.
676 */
677 static int
678 dtrace_canstore_remains(uint64_t addr, size_t sz, size_t *remain,
679 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
680 {
681 /*
682 * First, check to see if the address is in scratch space...
683 */
684 if (DTRACE_INRANGE(addr, sz, mstate->dtms_scratch_base,
685 mstate->dtms_scratch_size)) {
686 DTRACE_RANGE_REMAIN(remain, addr, mstate->dtms_scratch_base,
687 mstate->dtms_scratch_size);
688 return (1);
689 }
690
691 /*
692 * Now check to see if it's a dynamic variable. This check will pick
693 * up both thread-local variables and any global dynamically-allocated
694 * variables.
695 */
696 if (DTRACE_INRANGE(addr, sz, vstate->dtvs_dynvars.dtds_base,
697 vstate->dtvs_dynvars.dtds_size)) {
698 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
699 uintptr_t base = (uintptr_t)dstate->dtds_base +
700 (dstate->dtds_hashsize * sizeof (dtrace_dynhash_t));
701 uintptr_t chunkoffs;
702 dtrace_dynvar_t *dvar;
703
704 /*
705 * Before we assume that we can store here, we need to make
706 * sure that it isn't in our metadata -- storing to our
707 * dynamic variable metadata would corrupt our state. For
708 * the range to not include any dynamic variable metadata,
709 * it must:
710 *
711 * (1) Start above the hash table that is at the base of
712 * the dynamic variable space
713 *
714 * (2) Have a starting chunk offset that is beyond the
715 * dtrace_dynvar_t that is at the base of every chunk
716 *
717 * (3) Not span a chunk boundary
718 *
719 * (4) Not be in the tuple space of a dynamic variable
720 *
721 */
722 if (addr < base)
723 return (0);
724
725 chunkoffs = (addr - base) % dstate->dtds_chunksize;
726
727 if (chunkoffs < sizeof (dtrace_dynvar_t))
728 return (0);
729
730 if (chunkoffs + sz > dstate->dtds_chunksize)
731 return (0);
732
733 dvar = (dtrace_dynvar_t *)((uintptr_t)addr - chunkoffs);
734
735 if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE)
736 return (0);
737
738 if (chunkoffs < sizeof (dtrace_dynvar_t) +
739 ((dvar->dtdv_tuple.dtt_nkeys - 1) * sizeof (dtrace_key_t)))
740 return (0);
741
742 DTRACE_RANGE_REMAIN(remain, addr, dvar, dstate->dtds_chunksize);
743 return (1);
744 }
745
746 /*
747 * Finally, check the static local and global variables. These checks
748 * take the longest, so we perform them last.
749 */
750 if (dtrace_canstore_statvar(addr, sz, remain,
751 vstate->dtvs_locals, vstate->dtvs_nlocals))
752 return (1);
753
754 if (dtrace_canstore_statvar(addr, sz, remain,
755 vstate->dtvs_globals, vstate->dtvs_nglobals))
756 return (1);
757
758 return (0);
759 }
760
761
762 /*
763 * Convenience routine to check to see if the address is within a memory
764 * region in which a load may be issued given the user's privilege level;
765 * if not, it sets the appropriate error flags and loads 'addr' into the
766 * illegal value slot.
767 *
768 * DTrace subroutines (DIF_SUBR_*) should use this helper to implement
769 * appropriate memory access protection.
770 */
771 static int
772 dtrace_canload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
773 dtrace_vstate_t *vstate)
774 {
775 return (dtrace_canload_remains(addr, sz, NULL, mstate, vstate));
776 }
777
778 /*
779 * Implementation of dtrace_canload which communicates the upper bound of the
780 * allowed memory region.
781 */
782 static int
783 dtrace_canload_remains(uint64_t addr, size_t sz, size_t *remain,
784 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
785 {
786 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
787 file_t *fp;
788
789 /*
790 * If we hold the privilege to read from kernel memory, then
791 * everything is readable.
792 */
793 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) {
794 DTRACE_RANGE_REMAIN(remain, addr, addr, sz);
795 return (1);
796 }
797
798 /*
799 * You can obviously read that which you can store.
800 */
801 if (dtrace_canstore_remains(addr, sz, remain, mstate, vstate))
802 return (1);
803
804 /*
805 * We're allowed to read from our own string table.
806 */
807 if (DTRACE_INRANGE(addr, sz, mstate->dtms_difo->dtdo_strtab,
808 mstate->dtms_difo->dtdo_strlen)) {
809 DTRACE_RANGE_REMAIN(remain, addr,
810 mstate->dtms_difo->dtdo_strtab,
811 mstate->dtms_difo->dtdo_strlen);
812 return (1);
813 }
814
815 if (vstate->dtvs_state != NULL &&
816 dtrace_priv_proc(vstate->dtvs_state, mstate)) {
817 proc_t *p;
818
819 /*
820 * When we have privileges to the current process, there are
821 * several context-related kernel structures that are safe to
822 * read, even absent the privilege to read from kernel memory.
823 * These reads are safe because these structures contain only
824 * state that (1) we're permitted to read, (2) is harmless or
825 * (3) contains pointers to additional kernel state that we're
826 * not permitted to read (and as such, do not present an
827 * opportunity for privilege escalation). Finally (and
828 * critically), because of the nature of their relation with
829 * the current thread context, the memory associated with these
830 * structures cannot change over the duration of probe context,
831 * and it is therefore impossible for this memory to be
832 * deallocated and reallocated as something else while it's
833 * being operated upon.
834 */
835 if (DTRACE_INRANGE(addr, sz, curthread, sizeof (kthread_t))) {
836 DTRACE_RANGE_REMAIN(remain, addr, curthread,
837 sizeof (kthread_t));
838 return (1);
839 }
840
841 if ((p = curthread->t_procp) != NULL && DTRACE_INRANGE(addr,
842 sz, curthread->t_procp, sizeof (proc_t))) {
843 DTRACE_RANGE_REMAIN(remain, addr, curthread->t_procp,
844 sizeof (proc_t));
845 return (1);
846 }
847
848 if (curthread->t_cred != NULL && DTRACE_INRANGE(addr, sz,
849 curthread->t_cred, sizeof (cred_t))) {
850 DTRACE_RANGE_REMAIN(remain, addr, curthread->t_cred,
851 sizeof (cred_t));
852 return (1);
853 }
854
855 if (p != NULL && p->p_pidp != NULL && DTRACE_INRANGE(addr, sz,
856 &(p->p_pidp->pid_id), sizeof (pid_t))) {
857 DTRACE_RANGE_REMAIN(remain, addr, &(p->p_pidp->pid_id),
858 sizeof (pid_t));
859 return (1);
860 }
861
862 if (curthread->t_cpu != NULL && DTRACE_INRANGE(addr, sz,
863 curthread->t_cpu, offsetof(cpu_t, cpu_pause_thread))) {
864 DTRACE_RANGE_REMAIN(remain, addr, curthread->t_cpu,
865 offsetof(cpu_t, cpu_pause_thread));
866 return (1);
867 }
868 }
869
870 if ((fp = mstate->dtms_getf) != NULL) {
871 uintptr_t psz = sizeof (void *);
872 vnode_t *vp;
873 vnodeops_t *op;
874
875 /*
876 * When getf() returns a file_t, the enabling is implicitly
877 * granted the (transient) right to read the returned file_t
878 * as well as the v_path and v_op->vnop_name of the underlying
879 * vnode. These accesses are allowed after a successful
880 * getf() because the members that they refer to cannot change
881 * once set -- and the barrier logic in the kernel's closef()
882 * path assures that the file_t and its referenced vode_t
883 * cannot themselves be stale (that is, it impossible for
884 * either dtms_getf itself or its f_vnode member to reference
885 * freed memory).
886 */
887 if (DTRACE_INRANGE(addr, sz, fp, sizeof (file_t))) {
888 DTRACE_RANGE_REMAIN(remain, addr, fp, sizeof (file_t));
889 return (1);
890 }
891
892 if ((vp = fp->f_vnode) != NULL) {
893 size_t slen;
894
895 if (DTRACE_INRANGE(addr, sz, &vp->v_path, psz)) {
896 DTRACE_RANGE_REMAIN(remain, addr, &vp->v_path,
897 psz);
898 return (1);
899 }
900
901 slen = strlen(vp->v_path) + 1;
902 if (DTRACE_INRANGE(addr, sz, vp->v_path, slen)) {
903 DTRACE_RANGE_REMAIN(remain, addr, vp->v_path,
904 slen);
905 return (1);
906 }
907
908 if (DTRACE_INRANGE(addr, sz, &vp->v_op, psz)) {
909 DTRACE_RANGE_REMAIN(remain, addr, &vp->v_op,
910 psz);
911 return (1);
912 }
913
914 if ((op = vp->v_op) != NULL &&
915 DTRACE_INRANGE(addr, sz, &op->vnop_name, psz)) {
916 DTRACE_RANGE_REMAIN(remain, addr,
917 &op->vnop_name, psz);
918 return (1);
919 }
920
921 if (op != NULL && op->vnop_name != NULL &&
922 DTRACE_INRANGE(addr, sz, op->vnop_name,
923 (slen = strlen(op->vnop_name) + 1))) {
924 DTRACE_RANGE_REMAIN(remain, addr,
925 op->vnop_name, slen);
926 return (1);
927 }
928 }
929 }
930
931 DTRACE_CPUFLAG_SET(CPU_DTRACE_KPRIV);
932 *illval = addr;
933 return (0);
934 }
935
936 /*
937 * Convenience routine to check to see if a given string is within a memory
938 * region in which a load may be issued given the user's privilege level;
939 * this exists so that we don't need to issue unnecessary dtrace_strlen()
940 * calls in the event that the user has all privileges.
941 */
942 static int
943 dtrace_strcanload(uint64_t addr, size_t sz, size_t *remain,
944 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
945 {
946 size_t rsize;
947
948 /*
949 * If we hold the privilege to read from kernel memory, then
950 * everything is readable.
951 */
952 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) {
953 DTRACE_RANGE_REMAIN(remain, addr, addr, sz);
954 return (1);
955 }
956
957 /*
958 * Even if the caller is uninterested in querying the remaining valid
959 * range, it is required to ensure that the access is allowed.
960 */
961 if (remain == NULL) {
962 remain = &rsize;
963 }
964 if (dtrace_canload_remains(addr, 0, remain, mstate, vstate)) {
965 size_t strsz;
966 /*
967 * Perform the strlen after determining the length of the
968 * memory region which is accessible. This prevents timing
969 * information from being used to find NULs in memory which is
970 * not accessible to the caller.
971 */
972 strsz = 1 + dtrace_strlen((char *)(uintptr_t)addr,
973 MIN(sz, *remain));
974 if (strsz <= *remain) {
975 return (1);
976 }
977 }
978
979 return (0);
980 }
981
982 /*
983 * Convenience routine to check to see if a given variable is within a memory
984 * region in which a load may be issued given the user's privilege level.
985 */
986 static int
987 dtrace_vcanload(void *src, dtrace_diftype_t *type, size_t *remain,
988 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
989 {
990 size_t sz;
991 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
992
993 /*
994 * Calculate the max size before performing any checks since even
995 * DTRACE_ACCESS_KERNEL-credentialed callers expect that this function
996 * return the max length via 'remain'.
997 */
998 if (type->dtdt_kind == DIF_TYPE_STRING) {
999 dtrace_state_t *state = vstate->dtvs_state;
1000
1001 if (state != NULL) {
1002 sz = state->dts_options[DTRACEOPT_STRSIZE];
1003 } else {
1004 /*
1005 * In helper context, we have a NULL state; fall back
1006 * to using the system-wide default for the string size
1007 * in this case.
1008 */
1009 sz = dtrace_strsize_default;
1010 }
1011 } else {
1012 sz = type->dtdt_size;
1013 }
1014
1015 /*
1016 * If we hold the privilege to read from kernel memory, then
1017 * everything is readable.
1018 */
1019 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) {
1020 DTRACE_RANGE_REMAIN(remain, (uintptr_t)src, src, sz);
1021 return (1);
1022 }
1023
1024 if (type->dtdt_kind == DIF_TYPE_STRING) {
1025 return (dtrace_strcanload((uintptr_t)src, sz, remain, mstate,
1026 vstate));
1027 }
1028 return (dtrace_canload_remains((uintptr_t)src, sz, remain, mstate,
1029 vstate));
1030 }
1031
1032 /*
1033 * Convert a string to a signed integer using safe loads.
1034 *
1035 * NOTE: This function uses various macros from strtolctype.h to manipulate
1036 * digit values, etc -- these have all been checked to ensure they make
1037 * no additional function calls.
1038 */
1039 static int64_t
1040 dtrace_strtoll(char *input, int base, size_t limit)
1041 {
1042 uintptr_t pos = (uintptr_t)input;
1043 int64_t val = 0;
1044 int x;
1045 boolean_t neg = B_FALSE;
1046 char c, cc, ccc;
1047 uintptr_t end = pos + limit;
1048
1049 /*
1050 * Consume any whitespace preceding digits.
1051 */
1052 while ((c = dtrace_load8(pos)) == ' ' || c == '\t')
1053 pos++;
1054
1055 /*
1056 * Handle an explicit sign if one is present.
1057 */
1058 if (c == '-' || c == '+') {
1059 if (c == '-')
1060 neg = B_TRUE;
1061 c = dtrace_load8(++pos);
1062 }
1063
1064 /*
1065 * Check for an explicit hexadecimal prefix ("0x" or "0X") and skip it
1066 * if present.
1067 */
1068 if (base == 16 && c == '0' && ((cc = dtrace_load8(pos + 1)) == 'x' ||
1069 cc == 'X') && isxdigit(ccc = dtrace_load8(pos + 2))) {
1070 pos += 2;
1071 c = ccc;
1072 }
1073
1074 /*
1075 * Read in contiguous digits until the first non-digit character.
1076 */
1077 for (; pos < end && c != '\0' && lisalnum(c) && (x = DIGIT(c)) < base;
1078 c = dtrace_load8(++pos))
1079 val = val * base + x;
1080
1081 return (neg ? -val : val);
1082 }
1083
1084 /*
1085 * Compare two strings using safe loads.
1086 */
1087 static int
1088 dtrace_strncmp(char *s1, char *s2, size_t limit)
1089 {
1090 uint8_t c1, c2;
1091 volatile uint16_t *flags;
1092
1093 if (s1 == s2 || limit == 0)
1094 return (0);
1095
1096 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
1097
1098 do {
1099 if (s1 == NULL) {
1100 c1 = '\0';
1101 } else {
1102 c1 = dtrace_load8((uintptr_t)s1++);
1103 }
1104
1105 if (s2 == NULL) {
1106 c2 = '\0';
1107 } else {
1108 c2 = dtrace_load8((uintptr_t)s2++);
1109 }
1110
1111 if (c1 != c2)
1112 return (c1 - c2);
1113 } while (--limit && c1 != '\0' && !(*flags & CPU_DTRACE_FAULT));
1114
1115 return (0);
1116 }
1117
1118 /*
1119 * Compute strlen(s) for a string using safe memory accesses. The additional
1120 * len parameter is used to specify a maximum length to ensure completion.
1121 */
1122 static size_t
1123 dtrace_strlen(const char *s, size_t lim)
1124 {
1125 uint_t len;
1126
1127 for (len = 0; len != lim; len++) {
1128 if (dtrace_load8((uintptr_t)s++) == '\0')
1129 break;
1130 }
1131
1132 return (len);
1133 }
1134
1135 /*
1136 * Check if an address falls within a toxic region.
1137 */
1138 static int
1139 dtrace_istoxic(uintptr_t kaddr, size_t size)
1140 {
1141 uintptr_t taddr, tsize;
1142 int i;
1143
1144 for (i = 0; i < dtrace_toxranges; i++) {
1145 taddr = dtrace_toxrange[i].dtt_base;
1146 tsize = dtrace_toxrange[i].dtt_limit - taddr;
1147
1148 if (kaddr - taddr < tsize) {
1149 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
1150 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = kaddr;
1151 return (1);
1152 }
1153
1154 if (taddr - kaddr < size) {
1155 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
1156 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = taddr;
1157 return (1);
1158 }
1159 }
1160
1161 return (0);
1162 }
1163
1164 /*
1165 * Copy src to dst using safe memory accesses. The src is assumed to be unsafe
1166 * memory specified by the DIF program. The dst is assumed to be safe memory
1167 * that we can store to directly because it is managed by DTrace. As with
1168 * standard bcopy, overlapping copies are handled properly.
1169 */
1170 static void
1171 dtrace_bcopy(const void *src, void *dst, size_t len)
1172 {
1173 if (len != 0) {
1174 uint8_t *s1 = dst;
1175 const uint8_t *s2 = src;
1176
1177 if (s1 <= s2) {
1178 do {
1179 *s1++ = dtrace_load8((uintptr_t)s2++);
1180 } while (--len != 0);
1181 } else {
1182 s2 += len;
1183 s1 += len;
1184
1185 do {
1186 *--s1 = dtrace_load8((uintptr_t)--s2);
1187 } while (--len != 0);
1188 }
1189 }
1190 }
1191
1192 /*
1193 * Copy src to dst using safe memory accesses, up to either the specified
1194 * length, or the point that a nul byte is encountered. The src is assumed to
1195 * be unsafe memory specified by the DIF program. The dst is assumed to be
1196 * safe memory that we can store to directly because it is managed by DTrace.
1197 * Unlike dtrace_bcopy(), overlapping regions are not handled.
1198 */
1199 static void
1200 dtrace_strcpy(const void *src, void *dst, size_t len)
1201 {
1202 if (len != 0) {
1203 uint8_t *s1 = dst, c;
1204 const uint8_t *s2 = src;
1205
1206 do {
1207 *s1++ = c = dtrace_load8((uintptr_t)s2++);
1208 } while (--len != 0 && c != '\0');
1209 }
1210 }
1211
1212 /*
1213 * Copy src to dst, deriving the size and type from the specified (BYREF)
1214 * variable type. The src is assumed to be unsafe memory specified by the DIF
1215 * program. The dst is assumed to be DTrace variable memory that is of the
1216 * specified type; we assume that we can store to directly.
1217 */
1218 static void
1219 dtrace_vcopy(void *src, void *dst, dtrace_diftype_t *type, size_t limit)
1220 {
1221 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
1222
1223 if (type->dtdt_kind == DIF_TYPE_STRING) {
1224 dtrace_strcpy(src, dst, MIN(type->dtdt_size, limit));
1225 } else {
1226 dtrace_bcopy(src, dst, MIN(type->dtdt_size, limit));
1227 }
1228 }
1229
1230 /*
1231 * Compare s1 to s2 using safe memory accesses. The s1 data is assumed to be
1232 * unsafe memory specified by the DIF program. The s2 data is assumed to be
1233 * safe memory that we can access directly because it is managed by DTrace.
1234 */
1235 static int
1236 dtrace_bcmp(const void *s1, const void *s2, size_t len)
1237 {
1238 volatile uint16_t *flags;
1239
1240 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
1241
1242 if (s1 == s2)
1243 return (0);
1244
1245 if (s1 == NULL || s2 == NULL)
1246 return (1);
1247
1248 if (s1 != s2 && len != 0) {
1249 const uint8_t *ps1 = s1;
1250 const uint8_t *ps2 = s2;
1251
1252 do {
1253 if (dtrace_load8((uintptr_t)ps1++) != *ps2++)
1254 return (1);
1255 } while (--len != 0 && !(*flags & CPU_DTRACE_FAULT));
1256 }
1257 return (0);
1258 }
1259
1260 /*
1261 * Zero the specified region using a simple byte-by-byte loop. Note that this
1262 * is for safe DTrace-managed memory only.
1263 */
1264 static void
1265 dtrace_bzero(void *dst, size_t len)
1266 {
1267 uchar_t *cp;
1268
1269 for (cp = dst; len != 0; len--)
1270 *cp++ = 0;
1271 }
1272
1273 static void
1274 dtrace_add_128(uint64_t *addend1, uint64_t *addend2, uint64_t *sum)
1275 {
1276 uint64_t result[2];
1277
1278 result[0] = addend1[0] + addend2[0];
1279 result[1] = addend1[1] + addend2[1] +
1280 (result[0] < addend1[0] || result[0] < addend2[0] ? 1 : 0);
1281
1282 sum[0] = result[0];
1283 sum[1] = result[1];
1284 }
1285
1286 /*
1287 * Shift the 128-bit value in a by b. If b is positive, shift left.
1288 * If b is negative, shift right.
1289 */
1290 static void
1291 dtrace_shift_128(uint64_t *a, int b)
1292 {
1293 uint64_t mask;
1294
1295 if (b == 0)
1296 return;
1297
1298 if (b < 0) {
1299 b = -b;
1300 if (b >= 64) {
1301 a[0] = a[1] >> (b - 64);
1302 a[1] = 0;
1303 } else {
1304 a[0] >>= b;
1305 mask = 1LL << (64 - b);
1306 mask -= 1;
1307 a[0] |= ((a[1] & mask) << (64 - b));
1308 a[1] >>= b;
1309 }
1310 } else {
1311 if (b >= 64) {
1312 a[1] = a[0] << (b - 64);
1313 a[0] = 0;
1314 } else {
1315 a[1] <<= b;
1316 mask = a[0] >> (64 - b);
1317 a[1] |= mask;
1318 a[0] <<= b;
1319 }
1320 }
1321 }
1322
1323 /*
1324 * The basic idea is to break the 2 64-bit values into 4 32-bit values,
1325 * use native multiplication on those, and then re-combine into the
1326 * resulting 128-bit value.
1327 *
1328 * (hi1 << 32 + lo1) * (hi2 << 32 + lo2) =
1329 * hi1 * hi2 << 64 +
1330 * hi1 * lo2 << 32 +
1331 * hi2 * lo1 << 32 +
1332 * lo1 * lo2
1333 */
1334 static void
1335 dtrace_multiply_128(uint64_t factor1, uint64_t factor2, uint64_t *product)
1336 {
1337 uint64_t hi1, hi2, lo1, lo2;
1338 uint64_t tmp[2];
1339
1340 hi1 = factor1 >> 32;
1341 hi2 = factor2 >> 32;
1342
1343 lo1 = factor1 & DT_MASK_LO;
1344 lo2 = factor2 & DT_MASK_LO;
1345
1346 product[0] = lo1 * lo2;
1347 product[1] = hi1 * hi2;
1348
1349 tmp[0] = hi1 * lo2;
1350 tmp[1] = 0;
1351 dtrace_shift_128(tmp, 32);
1352 dtrace_add_128(product, tmp, product);
1353
1354 tmp[0] = hi2 * lo1;
1355 tmp[1] = 0;
1356 dtrace_shift_128(tmp, 32);
1357 dtrace_add_128(product, tmp, product);
1358 }
1359
1360 /*
1361 * This privilege check should be used by actions and subroutines to
1362 * verify that the user credentials of the process that enabled the
1363 * invoking ECB match the target credentials
1364 */
1365 static int
1366 dtrace_priv_proc_common_user(dtrace_state_t *state)
1367 {
1368 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1369
1370 /*
1371 * We should always have a non-NULL state cred here, since if cred
1372 * is null (anonymous tracing), we fast-path bypass this routine.
1373 */
1374 ASSERT(s_cr != NULL);
1375
1376 if ((cr = CRED()) != NULL &&
1377 s_cr->cr_uid == cr->cr_uid &&
1378 s_cr->cr_uid == cr->cr_ruid &&
1379 s_cr->cr_uid == cr->cr_suid &&
1380 s_cr->cr_gid == cr->cr_gid &&
1381 s_cr->cr_gid == cr->cr_rgid &&
1382 s_cr->cr_gid == cr->cr_sgid)
1383 return (1);
1384
1385 return (0);
1386 }
1387
1388 /*
1389 * This privilege check should be used by actions and subroutines to
1390 * verify that the zone of the process that enabled the invoking ECB
1391 * matches the target credentials
1392 */
1393 static int
1394 dtrace_priv_proc_common_zone(dtrace_state_t *state)
1395 {
1396 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1397
1398 /*
1399 * We should always have a non-NULL state cred here, since if cred
1400 * is null (anonymous tracing), we fast-path bypass this routine.
1401 */
1402 ASSERT(s_cr != NULL);
1403
1404 if ((cr = CRED()) != NULL && s_cr->cr_zone == cr->cr_zone)
1405 return (1);
1406
1407 return (0);
1408 }
1409
1410 /*
1411 * This privilege check should be used by actions and subroutines to
1412 * verify that the process has not setuid or changed credentials.
1413 */
1414 static int
1415 dtrace_priv_proc_common_nocd()
1416 {
1417 proc_t *proc;
1418
1419 if ((proc = ttoproc(curthread)) != NULL &&
1420 !(proc->p_flag & SNOCD))
1421 return (1);
1422
1423 return (0);
1424 }
1425
1426 static int
1427 dtrace_priv_proc_destructive(dtrace_state_t *state, dtrace_mstate_t *mstate)
1428 {
1429 int action = state->dts_cred.dcr_action;
1430
1431 if (!(mstate->dtms_access & DTRACE_ACCESS_PROC))
1432 goto bad;
1433
1434 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE) == 0) &&
1435 dtrace_priv_proc_common_zone(state) == 0)
1436 goto bad;
1437
1438 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER) == 0) &&
1439 dtrace_priv_proc_common_user(state) == 0)
1440 goto bad;
1441
1442 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG) == 0) &&
1443 dtrace_priv_proc_common_nocd() == 0)
1444 goto bad;
1445
1446 return (1);
1447
1448 bad:
1449 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1450
1451 return (0);
1452 }
1453
1454 static int
1455 dtrace_priv_proc_control(dtrace_state_t *state, dtrace_mstate_t *mstate)
1456 {
1457 if (mstate->dtms_access & DTRACE_ACCESS_PROC) {
1458 if (state->dts_cred.dcr_action & DTRACE_CRA_PROC_CONTROL)
1459 return (1);
1460
1461 if (dtrace_priv_proc_common_zone(state) &&
1462 dtrace_priv_proc_common_user(state) &&
1463 dtrace_priv_proc_common_nocd())
1464 return (1);
1465 }
1466
1467 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1468
1469 return (0);
1470 }
1471
1472 static int
1473 dtrace_priv_proc(dtrace_state_t *state, dtrace_mstate_t *mstate)
1474 {
1475 if ((mstate->dtms_access & DTRACE_ACCESS_PROC) &&
1476 (state->dts_cred.dcr_action & DTRACE_CRA_PROC))
1477 return (1);
1478
1479 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1480
1481 return (0);
1482 }
1483
1484 static int
1485 dtrace_priv_kernel(dtrace_state_t *state)
1486 {
1487 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL)
1488 return (1);
1489
1490 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1491
1492 return (0);
1493 }
1494
1495 static int
1496 dtrace_priv_kernel_destructive(dtrace_state_t *state)
1497 {
1498 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL_DESTRUCTIVE)
1499 return (1);
1500
1501 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1502
1503 return (0);
1504 }
1505
1506 /*
1507 * Determine if the dte_cond of the specified ECB allows for processing of
1508 * the current probe to continue. Note that this routine may allow continued
1509 * processing, but with access(es) stripped from the mstate's dtms_access
1510 * field.
1511 */
1512 static int
1513 dtrace_priv_probe(dtrace_state_t *state, dtrace_mstate_t *mstate,
1514 dtrace_ecb_t *ecb)
1515 {
1516 dtrace_probe_t *probe = ecb->dte_probe;
1517 dtrace_provider_t *prov = probe->dtpr_provider;
1518 dtrace_pops_t *pops = &prov->dtpv_pops;
1519 int mode = DTRACE_MODE_NOPRIV_DROP;
1520
1521 ASSERT(ecb->dte_cond);
1522
1523 if (pops->dtps_mode != NULL) {
1524 mode = pops->dtps_mode(prov->dtpv_arg,
1525 probe->dtpr_id, probe->dtpr_arg);
1526
1527 ASSERT(mode & (DTRACE_MODE_USER | DTRACE_MODE_KERNEL));
1528 ASSERT(mode & (DTRACE_MODE_NOPRIV_RESTRICT |
1529 DTRACE_MODE_NOPRIV_DROP));
1530 }
1531
1532 /*
1533 * If the dte_cond bits indicate that this consumer is only allowed to
1534 * see user-mode firings of this probe, check that the probe was fired
1535 * while in a user context. If that's not the case, use the policy
1536 * specified by the provider to determine if we drop the probe or
1537 * merely restrict operation.
1538 */
1539 if (ecb->dte_cond & DTRACE_COND_USERMODE) {
1540 ASSERT(mode != DTRACE_MODE_NOPRIV_DROP);
1541
1542 if (!(mode & DTRACE_MODE_USER)) {
1543 if (mode & DTRACE_MODE_NOPRIV_DROP)
1544 return (0);
1545
1546 mstate->dtms_access &= ~DTRACE_ACCESS_ARGS;
1547 }
1548 }
1549
1550 /*
1551 * This is more subtle than it looks. We have to be absolutely certain
1552 * that CRED() isn't going to change out from under us so it's only
1553 * legit to examine that structure if we're in constrained situations.
1554 * Currently, the only times we'll this check is if a non-super-user
1555 * has enabled the profile or syscall providers -- providers that
1556 * allow visibility of all processes. For the profile case, the check
1557 * above will ensure that we're examining a user context.
1558 */
1559 if (ecb->dte_cond & DTRACE_COND_OWNER) {
1560 cred_t *cr;
1561 cred_t *s_cr = state->dts_cred.dcr_cred;
1562 proc_t *proc;
1563
1564 ASSERT(s_cr != NULL);
1565
1566 if ((cr = CRED()) == NULL ||
1567 s_cr->cr_uid != cr->cr_uid ||
1568 s_cr->cr_uid != cr->cr_ruid ||
1569 s_cr->cr_uid != cr->cr_suid ||
1570 s_cr->cr_gid != cr->cr_gid ||
1571 s_cr->cr_gid != cr->cr_rgid ||
1572 s_cr->cr_gid != cr->cr_sgid ||
1573 (proc = ttoproc(curthread)) == NULL ||
1574 (proc->p_flag & SNOCD)) {
1575 if (mode & DTRACE_MODE_NOPRIV_DROP)
1576 return (0);
1577
1578 mstate->dtms_access &= ~DTRACE_ACCESS_PROC;
1579 }
1580 }
1581
1582 /*
1583 * If our dte_cond is set to DTRACE_COND_ZONEOWNER and we are not
1584 * in our zone, check to see if our mode policy is to restrict rather
1585 * than to drop; if to restrict, strip away both DTRACE_ACCESS_PROC
1586 * and DTRACE_ACCESS_ARGS
1587 */
1588 if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) {
1589 cred_t *cr;
1590 cred_t *s_cr = state->dts_cred.dcr_cred;
1591
1592 ASSERT(s_cr != NULL);
1593
1594 if ((cr = CRED()) == NULL ||
1595 s_cr->cr_zone->zone_id != cr->cr_zone->zone_id) {
1596 if (mode & DTRACE_MODE_NOPRIV_DROP)
1597 return (0);
1598
1599 mstate->dtms_access &=
1600 ~(DTRACE_ACCESS_PROC | DTRACE_ACCESS_ARGS);
1601 }
1602 }
1603
1604 /*
1605 * By merits of being in this code path at all, we have limited
1606 * privileges. If the provider has indicated that limited privileges
1607 * are to denote restricted operation, strip off the ability to access
1608 * arguments.
1609 */
1610 if (mode & DTRACE_MODE_LIMITEDPRIV_RESTRICT)
1611 mstate->dtms_access &= ~DTRACE_ACCESS_ARGS;
1612
1613 return (1);
1614 }
1615
1616 /*
1617 * Note: not called from probe context. This function is called
1618 * asynchronously (and at a regular interval) from outside of probe context to
1619 * clean the dirty dynamic variable lists on all CPUs. Dynamic variable
1620 * cleaning is explained in detail in <sys/dtrace_impl.h>.
1621 */
1622 void
1623 dtrace_dynvar_clean(dtrace_dstate_t *dstate)
1624 {
1625 dtrace_dynvar_t *dirty;
1626 dtrace_dstate_percpu_t *dcpu;
1627 dtrace_dynvar_t **rinsep;
1628 int i, j, work = 0;
1629
1630 for (i = 0; i < NCPU; i++) {
1631 dcpu = &dstate->dtds_percpu[i];
1632 rinsep = &dcpu->dtdsc_rinsing;
1633
1634 /*
1635 * If the dirty list is NULL, there is no dirty work to do.
1636 */
1637 if (dcpu->dtdsc_dirty == NULL)
1638 continue;
1639
1640 if (dcpu->dtdsc_rinsing != NULL) {
1641 /*
1642 * If the rinsing list is non-NULL, then it is because
1643 * this CPU was selected to accept another CPU's
1644 * dirty list -- and since that time, dirty buffers
1645 * have accumulated. This is a highly unlikely
1646 * condition, but we choose to ignore the dirty
1647 * buffers -- they'll be picked up a future cleanse.
1648 */
1649 continue;
1650 }
1651
1652 if (dcpu->dtdsc_clean != NULL) {
1653 /*
1654 * If the clean list is non-NULL, then we're in a
1655 * situation where a CPU has done deallocations (we
1656 * have a non-NULL dirty list) but no allocations (we
1657 * also have a non-NULL clean list). We can't simply
1658 * move the dirty list into the clean list on this
1659 * CPU, yet we also don't want to allow this condition
1660 * to persist, lest a short clean list prevent a
1661 * massive dirty list from being cleaned (which in
1662 * turn could lead to otherwise avoidable dynamic
1663 * drops). To deal with this, we look for some CPU
1664 * with a NULL clean list, NULL dirty list, and NULL
1665 * rinsing list -- and then we borrow this CPU to
1666 * rinse our dirty list.
1667 */
1668 for (j = 0; j < NCPU; j++) {
1669 dtrace_dstate_percpu_t *rinser;
1670
1671 rinser = &dstate->dtds_percpu[j];
1672
1673 if (rinser->dtdsc_rinsing != NULL)
1674 continue;
1675
1676 if (rinser->dtdsc_dirty != NULL)
1677 continue;
1678
1679 if (rinser->dtdsc_clean != NULL)
1680 continue;
1681
1682 rinsep = &rinser->dtdsc_rinsing;
1683 break;
1684 }
1685
1686 if (j == NCPU) {
1687 /*
1688 * We were unable to find another CPU that
1689 * could accept this dirty list -- we are
1690 * therefore unable to clean it now.
1691 */
1692 dtrace_dynvar_failclean++;
1693 continue;
1694 }
1695 }
1696
1697 work = 1;
1698
1699 /*
1700 * Atomically move the dirty list aside.
1701 */
1702 do {
1703 dirty = dcpu->dtdsc_dirty;
1704
1705 /*
1706 * Before we zap the dirty list, set the rinsing list.
1707 * (This allows for a potential assertion in
1708 * dtrace_dynvar(): if a free dynamic variable appears
1709 * on a hash chain, either the dirty list or the
1710 * rinsing list for some CPU must be non-NULL.)
1711 */
1712 *rinsep = dirty;
1713 dtrace_membar_producer();
1714 } while (dtrace_casptr(&dcpu->dtdsc_dirty,
1715 dirty, NULL) != dirty);
1716 }
1717
1718 if (!work) {
1719 /*
1720 * We have no work to do; we can simply return.
1721 */
1722 return;
1723 }
1724
1725 dtrace_sync();
1726
1727 for (i = 0; i < NCPU; i++) {
1728 dcpu = &dstate->dtds_percpu[i];
1729
1730 if (dcpu->dtdsc_rinsing == NULL)
1731 continue;
1732
1733 /*
1734 * We are now guaranteed that no hash chain contains a pointer
1735 * into this dirty list; we can make it clean.
1736 */
1737 ASSERT(dcpu->dtdsc_clean == NULL);
1738 dcpu->dtdsc_clean = dcpu->dtdsc_rinsing;
1739 dcpu->dtdsc_rinsing = NULL;
1740 }
1741
1742 /*
1743 * Before we actually set the state to be DTRACE_DSTATE_CLEAN, make
1744 * sure that all CPUs have seen all of the dtdsc_clean pointers.
1745 * This prevents a race whereby a CPU incorrectly decides that
1746 * the state should be something other than DTRACE_DSTATE_CLEAN
1747 * after dtrace_dynvar_clean() has completed.
1748 */
1749 dtrace_sync();
1750
1751 dstate->dtds_state = DTRACE_DSTATE_CLEAN;
1752 }
1753
1754 /*
1755 * Depending on the value of the op parameter, this function looks-up,
1756 * allocates or deallocates an arbitrarily-keyed dynamic variable. If an
1757 * allocation is requested, this function will return a pointer to a
1758 * dtrace_dynvar_t corresponding to the allocated variable -- or NULL if no
1759 * variable can be allocated. If NULL is returned, the appropriate counter
1760 * will be incremented.
1761 */
1762 dtrace_dynvar_t *
1763 dtrace_dynvar(dtrace_dstate_t *dstate, uint_t nkeys,
1764 dtrace_key_t *key, size_t dsize, dtrace_dynvar_op_t op,
1765 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
1766 {
1767 uint64_t hashval = DTRACE_DYNHASH_VALID;
1768 dtrace_dynhash_t *hash = dstate->dtds_hash;
1769 dtrace_dynvar_t *free, *new_free, *next, *dvar, *start, *prev = NULL;
1770 processorid_t me = CPU->cpu_id, cpu = me;
1771 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[me];
1772 size_t bucket, ksize;
1773 size_t chunksize = dstate->dtds_chunksize;
1774 uintptr_t kdata, lock, nstate;
1775 uint_t i;
1776
1777 ASSERT(nkeys != 0);
1778
1779 /*
1780 * Hash the key. As with aggregations, we use Jenkins' "One-at-a-time"
1781 * algorithm. For the by-value portions, we perform the algorithm in
1782 * 16-bit chunks (as opposed to 8-bit chunks). This speeds things up a
1783 * bit, and seems to have only a minute effect on distribution. For
1784 * the by-reference data, we perform "One-at-a-time" iterating (safely)
1785 * over each referenced byte. It's painful to do this, but it's much
1786 * better than pathological hash distribution. The efficacy of the
1787 * hashing algorithm (and a comparison with other algorithms) may be
1788 * found by running the ::dtrace_dynstat MDB dcmd.
1789 */
1790 for (i = 0; i < nkeys; i++) {
1791 if (key[i].dttk_size == 0) {
1792 uint64_t val = key[i].dttk_value;
1793
1794 hashval += (val >> 48) & 0xffff;
1795 hashval += (hashval << 10);
1796 hashval ^= (hashval >> 6);
1797
1798 hashval += (val >> 32) & 0xffff;
1799 hashval += (hashval << 10);
1800 hashval ^= (hashval >> 6);
1801
1802 hashval += (val >> 16) & 0xffff;
1803 hashval += (hashval << 10);
1804 hashval ^= (hashval >> 6);
1805
1806 hashval += val & 0xffff;
1807 hashval += (hashval << 10);
1808 hashval ^= (hashval >> 6);
1809 } else {
1810 /*
1811 * This is incredibly painful, but it beats the hell
1812 * out of the alternative.
1813 */
1814 uint64_t j, size = key[i].dttk_size;
1815 uintptr_t base = (uintptr_t)key[i].dttk_value;
1816
1817 if (!dtrace_canload(base, size, mstate, vstate))
1818 break;
1819
1820 for (j = 0; j < size; j++) {
1821 hashval += dtrace_load8(base + j);
1822 hashval += (hashval << 10);
1823 hashval ^= (hashval >> 6);
1824 }
1825 }
1826 }
1827
1828 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT))
1829 return (NULL);
1830
1831 hashval += (hashval << 3);
1832 hashval ^= (hashval >> 11);
1833 hashval += (hashval << 15);
1834
1835 /*
1836 * There is a remote chance (ideally, 1 in 2^31) that our hashval
1837 * comes out to be one of our two sentinel hash values. If this
1838 * actually happens, we set the hashval to be a value known to be a
1839 * non-sentinel value.
1840 */
1841 if (hashval == DTRACE_DYNHASH_FREE || hashval == DTRACE_DYNHASH_SINK)
1842 hashval = DTRACE_DYNHASH_VALID;
1843
1844 /*
1845 * Yes, it's painful to do a divide here. If the cycle count becomes
1846 * important here, tricks can be pulled to reduce it. (However, it's
1847 * critical that hash collisions be kept to an absolute minimum;
1848 * they're much more painful than a divide.) It's better to have a
1849 * solution that generates few collisions and still keeps things
1850 * relatively simple.
1851 */
1852 bucket = hashval % dstate->dtds_hashsize;
1853
1854 if (op == DTRACE_DYNVAR_DEALLOC) {
1855 volatile uintptr_t *lockp = &hash[bucket].dtdh_lock;
1856
1857 for (;;) {
1858 while ((lock = *lockp) & 1)
1859 continue;
1860
1861 if (dtrace_casptr((void *)lockp,
1862 (void *)lock, (void *)(lock + 1)) == (void *)lock)
1863 break;
1864 }
1865
1866 dtrace_membar_producer();
1867 }
1868
1869 top:
1870 prev = NULL;
1871 lock = hash[bucket].dtdh_lock;
1872
1873 dtrace_membar_consumer();
1874
1875 start = hash[bucket].dtdh_chain;
1876 ASSERT(start != NULL && (start->dtdv_hashval == DTRACE_DYNHASH_SINK ||
1877 start->dtdv_hashval != DTRACE_DYNHASH_FREE ||
1878 op != DTRACE_DYNVAR_DEALLOC));
1879
1880 for (dvar = start; dvar != NULL; dvar = dvar->dtdv_next) {
1881 dtrace_tuple_t *dtuple = &dvar->dtdv_tuple;
1882 dtrace_key_t *dkey = &dtuple->dtt_key[0];
1883
1884 if (dvar->dtdv_hashval != hashval) {
1885 if (dvar->dtdv_hashval == DTRACE_DYNHASH_SINK) {
1886 /*
1887 * We've reached the sink, and therefore the
1888 * end of the hash chain; we can kick out of
1889 * the loop knowing that we have seen a valid
1890 * snapshot of state.
1891 */
1892 ASSERT(dvar->dtdv_next == NULL);
1893 ASSERT(dvar == &dtrace_dynhash_sink);
1894 break;
1895 }
1896
1897 if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) {
1898 /*
1899 * We've gone off the rails: somewhere along
1900 * the line, one of the members of this hash
1901 * chain was deleted. Note that we could also
1902 * detect this by simply letting this loop run
1903 * to completion, as we would eventually hit
1904 * the end of the dirty list. However, we
1905 * want to avoid running the length of the
1906 * dirty list unnecessarily (it might be quite
1907 * long), so we catch this as early as
1908 * possible by detecting the hash marker. In
1909 * this case, we simply set dvar to NULL and
1910 * break; the conditional after the loop will
1911 * send us back to top.
1912 */
1913 dvar = NULL;
1914 break;
1915 }
1916
1917 goto next;
1918 }
1919
1920 if (dtuple->dtt_nkeys != nkeys)
1921 goto next;
1922
1923 for (i = 0; i < nkeys; i++, dkey++) {
1924 if (dkey->dttk_size != key[i].dttk_size)
1925 goto next; /* size or type mismatch */
1926
1927 if (dkey->dttk_size != 0) {
1928 if (dtrace_bcmp(
1929 (void *)(uintptr_t)key[i].dttk_value,
1930 (void *)(uintptr_t)dkey->dttk_value,
1931 dkey->dttk_size))
1932 goto next;
1933 } else {
1934 if (dkey->dttk_value != key[i].dttk_value)
1935 goto next;
1936 }
1937 }
1938
1939 if (op != DTRACE_DYNVAR_DEALLOC)
1940 return (dvar);
1941
1942 ASSERT(dvar->dtdv_next == NULL ||
1943 dvar->dtdv_next->dtdv_hashval != DTRACE_DYNHASH_FREE);
1944
1945 if (prev != NULL) {
1946 ASSERT(hash[bucket].dtdh_chain != dvar);
1947 ASSERT(start != dvar);
1948 ASSERT(prev->dtdv_next == dvar);
1949 prev->dtdv_next = dvar->dtdv_next;
1950 } else {
1951 if (dtrace_casptr(&hash[bucket].dtdh_chain,
1952 start, dvar->dtdv_next) != start) {
1953 /*
1954 * We have failed to atomically swing the
1955 * hash table head pointer, presumably because
1956 * of a conflicting allocation on another CPU.
1957 * We need to reread the hash chain and try
1958 * again.
1959 */
1960 goto top;
1961 }
1962 }
1963
1964 dtrace_membar_producer();
1965
1966 /*
1967 * Now set the hash value to indicate that it's free.
1968 */
1969 ASSERT(hash[bucket].dtdh_chain != dvar);
1970 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
1971
1972 dtrace_membar_producer();
1973
1974 /*
1975 * Set the next pointer to point at the dirty list, and
1976 * atomically swing the dirty pointer to the newly freed dvar.
1977 */
1978 do {
1979 next = dcpu->dtdsc_dirty;
1980 dvar->dtdv_next = next;
1981 } while (dtrace_casptr(&dcpu->dtdsc_dirty, next, dvar) != next);
1982
1983 /*
1984 * Finally, unlock this hash bucket.
1985 */
1986 ASSERT(hash[bucket].dtdh_lock == lock);
1987 ASSERT(lock & 1);
1988 hash[bucket].dtdh_lock++;
1989
1990 return (NULL);
1991 next:
1992 prev = dvar;
1993 continue;
1994 }
1995
1996 if (dvar == NULL) {
1997 /*
1998 * If dvar is NULL, it is because we went off the rails:
1999 * one of the elements that we traversed in the hash chain
2000 * was deleted while we were traversing it. In this case,
2001 * we assert that we aren't doing a dealloc (deallocs lock
2002 * the hash bucket to prevent themselves from racing with
2003 * one another), and retry the hash chain traversal.
2004 */
2005 ASSERT(op != DTRACE_DYNVAR_DEALLOC);
2006 goto top;
2007 }
2008
2009 if (op != DTRACE_DYNVAR_ALLOC) {
2010 /*
2011 * If we are not to allocate a new variable, we want to
2012 * return NULL now. Before we return, check that the value
2013 * of the lock word hasn't changed. If it has, we may have
2014 * seen an inconsistent snapshot.
2015 */
2016 if (op == DTRACE_DYNVAR_NOALLOC) {
2017 if (hash[bucket].dtdh_lock != lock)
2018 goto top;
2019 } else {
2020 ASSERT(op == DTRACE_DYNVAR_DEALLOC);
2021 ASSERT(hash[bucket].dtdh_lock == lock);
2022 ASSERT(lock & 1);
2023 hash[bucket].dtdh_lock++;
2024 }
2025
2026 return (NULL);
2027 }
2028
2029 /*
2030 * We need to allocate a new dynamic variable. The size we need is the
2031 * size of dtrace_dynvar plus the size of nkeys dtrace_key_t's plus the
2032 * size of any auxiliary key data (rounded up to 8-byte alignment) plus
2033 * the size of any referred-to data (dsize). We then round the final
2034 * size up to the chunksize for allocation.
2035 */
2036 for (ksize = 0, i = 0; i < nkeys; i++)
2037 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
2038
2039 /*
2040 * This should be pretty much impossible, but could happen if, say,
2041 * strange DIF specified the tuple. Ideally, this should be an
2042 * assertion and not an error condition -- but that requires that the
2043 * chunksize calculation in dtrace_difo_chunksize() be absolutely
2044 * bullet-proof. (That is, it must not be able to be fooled by
2045 * malicious DIF.) Given the lack of backwards branches in DIF,
2046 * solving this would presumably not amount to solving the Halting
2047 * Problem -- but it still seems awfully hard.
2048 */
2049 if (sizeof (dtrace_dynvar_t) + sizeof (dtrace_key_t) * (nkeys - 1) +
2050 ksize + dsize > chunksize) {
2051 dcpu->dtdsc_drops++;
2052 return (NULL);
2053 }
2054
2055 nstate = DTRACE_DSTATE_EMPTY;
2056
2057 do {
2058 retry:
2059 free = dcpu->dtdsc_free;
2060
2061 if (free == NULL) {
2062 dtrace_dynvar_t *clean = dcpu->dtdsc_clean;
2063 void *rval;
2064
2065 if (clean == NULL) {
2066 /*
2067 * We're out of dynamic variable space on
2068 * this CPU. Unless we have tried all CPUs,
2069 * we'll try to allocate from a different
2070 * CPU.
2071 */
2072 switch (dstate->dtds_state) {
2073 case DTRACE_DSTATE_CLEAN: {
2074 void *sp = &dstate->dtds_state;
2075
2076 if (++cpu >= NCPU)
2077 cpu = 0;
2078
2079 if (dcpu->dtdsc_dirty != NULL &&
2080 nstate == DTRACE_DSTATE_EMPTY)
2081 nstate = DTRACE_DSTATE_DIRTY;
2082
2083 if (dcpu->dtdsc_rinsing != NULL)
2084 nstate = DTRACE_DSTATE_RINSING;
2085
2086 dcpu = &dstate->dtds_percpu[cpu];
2087
2088 if (cpu != me)
2089 goto retry;
2090
2091 (void) dtrace_cas32(sp,
2092 DTRACE_DSTATE_CLEAN, nstate);
2093
2094 /*
2095 * To increment the correct bean
2096 * counter, take another lap.
2097 */
2098 goto retry;
2099 }
2100
2101 case DTRACE_DSTATE_DIRTY:
2102 dcpu->dtdsc_dirty_drops++;
2103 break;
2104
2105 case DTRACE_DSTATE_RINSING:
2106 dcpu->dtdsc_rinsing_drops++;
2107 break;
2108
2109 case DTRACE_DSTATE_EMPTY:
2110 dcpu->dtdsc_drops++;
2111 break;
2112 }
2113
2114 DTRACE_CPUFLAG_SET(CPU_DTRACE_DROP);
2115 return (NULL);
2116 }
2117
2118 /*
2119 * The clean list appears to be non-empty. We want to
2120 * move the clean list to the free list; we start by
2121 * moving the clean pointer aside.
2122 */
2123 if (dtrace_casptr(&dcpu->dtdsc_clean,
2124 clean, NULL) != clean) {
2125 /*
2126 * We are in one of two situations:
2127 *
2128 * (a) The clean list was switched to the
2129 * free list by another CPU.
2130 *
2131 * (b) The clean list was added to by the
2132 * cleansing cyclic.
2133 *
2134 * In either of these situations, we can
2135 * just reattempt the free list allocation.
2136 */
2137 goto retry;
2138 }
2139
2140 ASSERT(clean->dtdv_hashval == DTRACE_DYNHASH_FREE);
2141
2142 /*
2143 * Now we'll move the clean list to our free list.
2144 * It's impossible for this to fail: the only way
2145 * the free list can be updated is through this
2146 * code path, and only one CPU can own the clean list.
2147 * Thus, it would only be possible for this to fail if
2148 * this code were racing with dtrace_dynvar_clean().
2149 * (That is, if dtrace_dynvar_clean() updated the clean
2150 * list, and we ended up racing to update the free
2151 * list.) This race is prevented by the dtrace_sync()
2152 * in dtrace_dynvar_clean() -- which flushes the
2153 * owners of the clean lists out before resetting
2154 * the clean lists.
2155 */
2156 dcpu = &dstate->dtds_percpu[me];
2157 rval = dtrace_casptr(&dcpu->dtdsc_free, NULL, clean);
2158 ASSERT(rval == NULL);
2159 goto retry;
2160 }
2161
2162 dvar = free;
2163 new_free = dvar->dtdv_next;
2164 } while (dtrace_casptr(&dcpu->dtdsc_free, free, new_free) != free);
2165
2166 /*
2167 * We have now allocated a new chunk. We copy the tuple keys into the
2168 * tuple array and copy any referenced key data into the data space
2169 * following the tuple array. As we do this, we relocate dttk_value
2170 * in the final tuple to point to the key data address in the chunk.
2171 */
2172 kdata = (uintptr_t)&dvar->dtdv_tuple.dtt_key[nkeys];
2173 dvar->dtdv_data = (void *)(kdata + ksize);
2174 dvar->dtdv_tuple.dtt_nkeys = nkeys;
2175
2176 for (i = 0; i < nkeys; i++) {
2177 dtrace_key_t *dkey = &dvar->dtdv_tuple.dtt_key[i];
2178 size_t kesize = key[i].dttk_size;
2179
2180 if (kesize != 0) {
2181 dtrace_bcopy(
2182 (const void *)(uintptr_t)key[i].dttk_value,
2183 (void *)kdata, kesize);
2184 dkey->dttk_value = kdata;
2185 kdata += P2ROUNDUP(kesize, sizeof (uint64_t));
2186 } else {
2187 dkey->dttk_value = key[i].dttk_value;
2188 }
2189
2190 dkey->dttk_size = kesize;
2191 }
2192
2193 ASSERT(dvar->dtdv_hashval == DTRACE_DYNHASH_FREE);
2194 dvar->dtdv_hashval = hashval;
2195 dvar->dtdv_next = start;
2196
2197 if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar) == start)
2198 return (dvar);
2199
2200 /*
2201 * The cas has failed. Either another CPU is adding an element to
2202 * this hash chain, or another CPU is deleting an element from this
2203 * hash chain. The simplest way to deal with both of these cases
2204 * (though not necessarily the most efficient) is to free our
2205 * allocated block and re-attempt it all. Note that the free is
2206 * to the dirty list and _not_ to the free list. This is to prevent
2207 * races with allocators, above.
2208 */
2209 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
2210
2211 dtrace_membar_producer();
2212
2213 do {
2214 free = dcpu->dtdsc_dirty;
2215 dvar->dtdv_next = free;
2216 } while (dtrace_casptr(&dcpu->dtdsc_dirty, free, dvar) != free);
2217
2218 goto top;
2219 }
2220
2221 /*ARGSUSED*/
2222 static void
2223 dtrace_aggregate_min(uint64_t *oval, uint64_t nval, uint64_t arg)
2224 {
2225 if ((int64_t)nval < (int64_t)*oval)
2226 *oval = nval;
2227 }
2228
2229 /*ARGSUSED*/
2230 static void
2231 dtrace_aggregate_max(uint64_t *oval, uint64_t nval, uint64_t arg)
2232 {
2233 if ((int64_t)nval > (int64_t)*oval)
2234 *oval = nval;
2235 }
2236
2237 static void
2238 dtrace_aggregate_quantize(uint64_t *quanta, uint64_t nval, uint64_t incr)
2239 {
2240 int i, zero = DTRACE_QUANTIZE_ZEROBUCKET;
2241 int64_t val = (int64_t)nval;
2242
2243 if (val < 0) {
2244 for (i = 0; i < zero; i++) {
2245 if (val <= DTRACE_QUANTIZE_BUCKETVAL(i)) {
2246 quanta[i] += incr;
2247 return;
2248 }
2249 }
2250 } else {
2251 for (i = zero + 1; i < DTRACE_QUANTIZE_NBUCKETS; i++) {
2252 if (val < DTRACE_QUANTIZE_BUCKETVAL(i)) {
2253 quanta[i - 1] += incr;
2254 return;
2255 }
2256 }
2257
2258 quanta[DTRACE_QUANTIZE_NBUCKETS - 1] += incr;
2259 return;
2260 }
2261
2262 ASSERT(0);
2263 }
2264
2265 static void
2266 dtrace_aggregate_lquantize(uint64_t *lquanta, uint64_t nval, uint64_t incr)
2267 {
2268 uint64_t arg = *lquanta++;
2269 int32_t base = DTRACE_LQUANTIZE_BASE(arg);
2270 uint16_t step = DTRACE_LQUANTIZE_STEP(arg);
2271 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(arg);
2272 int32_t val = (int32_t)nval, level;
2273
2274 ASSERT(step != 0);
2275 ASSERT(levels != 0);
2276
2277 if (val < base) {
2278 /*
2279 * This is an underflow.
2280 */
2281 lquanta[0] += incr;
2282 return;
2283 }
2284
2285 level = (val - base) / step;
2286
2287 if (level < levels) {
2288 lquanta[level + 1] += incr;
2289 return;
2290 }
2291
2292 /*
2293 * This is an overflow.
2294 */
2295 lquanta[levels + 1] += incr;
2296 }
2297
2298 static int
2299 dtrace_aggregate_llquantize_bucket(uint16_t factor, uint16_t low,
2300 uint16_t high, uint16_t nsteps, int64_t value)
2301 {
2302 int64_t this = 1, last, next;
2303 int base = 1, order;
2304
2305 ASSERT(factor <= nsteps);
2306 ASSERT(nsteps % factor == 0);
2307
2308 for (order = 0; order < low; order++)
2309 this *= factor;
2310
2311 /*
2312 * If our value is less than our factor taken to the power of the
2313 * low order of magnitude, it goes into the zeroth bucket.
2314 */
2315 if (value < (last = this))
2316 return (0);
2317
2318 for (this *= factor; order <= high; order++) {
2319 int nbuckets = this > nsteps ? nsteps : this;
2320
2321 if ((next = this * factor) < this) {
2322 /*
2323 * We should not generally get log/linear quantizations
2324 * with a high magnitude that allows 64-bits to
2325 * overflow, but we nonetheless protect against this
2326 * by explicitly checking for overflow, and clamping
2327 * our value accordingly.
2328 */
2329 value = this - 1;
2330 }
2331
2332 if (value < this) {
2333 /*
2334 * If our value lies within this order of magnitude,
2335 * determine its position by taking the offset within
2336 * the order of magnitude, dividing by the bucket
2337 * width, and adding to our (accumulated) base.
2338 */
2339 return (base + (value - last) / (this / nbuckets));
2340 }
2341
2342 base += nbuckets - (nbuckets / factor);
2343 last = this;
2344 this = next;
2345 }
2346
2347 /*
2348 * Our value is greater than or equal to our factor taken to the
2349 * power of one plus the high magnitude -- return the top bucket.
2350 */
2351 return (base);
2352 }
2353
2354 static void
2355 dtrace_aggregate_llquantize(uint64_t *llquanta, uint64_t nval, uint64_t incr)
2356 {
2357 uint64_t arg = *llquanta++;
2358 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg);
2359 uint16_t low = DTRACE_LLQUANTIZE_LOW(arg);
2360 uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg);
2361 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg);
2362
2363 llquanta[dtrace_aggregate_llquantize_bucket(factor,
2364 low, high, nsteps, nval)] += incr;
2365 }
2366
2367 /*ARGSUSED*/
2368 static void
2369 dtrace_aggregate_avg(uint64_t *data, uint64_t nval, uint64_t arg)
2370 {
2371 data[0]++;
2372 data[1] += nval;
2373 }
2374
2375 /*ARGSUSED*/
2376 static void
2377 dtrace_aggregate_stddev(uint64_t *data, uint64_t nval, uint64_t arg)
2378 {
2379 int64_t snval = (int64_t)nval;
2380 uint64_t tmp[2];
2381
2382 data[0]++;
2383 data[1] += nval;
2384
2385 /*
2386 * What we want to say here is:
2387 *
2388 * data[2] += nval * nval;
2389 *
2390 * But given that nval is 64-bit, we could easily overflow, so
2391 * we do this as 128-bit arithmetic.
2392 */
2393 if (snval < 0)
2394 snval = -snval;
2395
2396 dtrace_multiply_128((uint64_t)snval, (uint64_t)snval, tmp);
2397 dtrace_add_128(data + 2, tmp, data + 2);
2398 }
2399
2400 /*ARGSUSED*/
2401 static void
2402 dtrace_aggregate_count(uint64_t *oval, uint64_t nval, uint64_t arg)
2403 {
2404 *oval = *oval + 1;
2405 }
2406
2407 /*ARGSUSED*/
2408 static void
2409 dtrace_aggregate_sum(uint64_t *oval, uint64_t nval, uint64_t arg)
2410 {
2411 *oval += nval;
2412 }
2413
2414 /*
2415 * Aggregate given the tuple in the principal data buffer, and the aggregating
2416 * action denoted by the specified dtrace_aggregation_t. The aggregation
2417 * buffer is specified as the buf parameter. This routine does not return
2418 * failure; if there is no space in the aggregation buffer, the data will be
2419 * dropped, and a corresponding counter incremented.
2420 */
2421 static void
2422 dtrace_aggregate(dtrace_aggregation_t *agg, dtrace_buffer_t *dbuf,
2423 intptr_t offset, dtrace_buffer_t *buf, uint64_t expr, uint64_t arg)
2424 {
2425 dtrace_recdesc_t *rec = &agg->dtag_action.dta_rec;
2426 uint32_t i, ndx, size, fsize;
2427 uint32_t align = sizeof (uint64_t) - 1;
2428 dtrace_aggbuffer_t *agb;
2429 dtrace_aggkey_t *key;
2430 uint32_t hashval = 0, limit, isstr;
2431 caddr_t tomax, data, kdata;
2432 dtrace_actkind_t action;
2433 dtrace_action_t *act;
2434 uintptr_t offs;
2435
2436 if (buf == NULL)
2437 return;
2438
2439 if (!agg->dtag_hasarg) {
2440 /*
2441 * Currently, only quantize() and lquantize() take additional
2442 * arguments, and they have the same semantics: an increment
2443 * value that defaults to 1 when not present. If additional
2444 * aggregating actions take arguments, the setting of the
2445 * default argument value will presumably have to become more
2446 * sophisticated...
2447 */
2448 arg = 1;
2449 }
2450
2451 action = agg->dtag_action.dta_kind - DTRACEACT_AGGREGATION;
2452 size = rec->dtrd_offset - agg->dtag_base;
2453 fsize = size + rec->dtrd_size;
2454
2455 ASSERT(dbuf->dtb_tomax != NULL);
2456 data = dbuf->dtb_tomax + offset + agg->dtag_base;
2457
2458 if ((tomax = buf->dtb_tomax) == NULL) {
2459 dtrace_buffer_drop(buf);
2460 return;
2461 }
2462
2463 /*
2464 * The metastructure is always at the bottom of the buffer.
2465 */
2466 agb = (dtrace_aggbuffer_t *)(tomax + buf->dtb_size -
2467 sizeof (dtrace_aggbuffer_t));
2468
2469 if (buf->dtb_offset == 0) {
2470 /*
2471 * We just kludge up approximately 1/8th of the size to be
2472 * buckets. If this guess ends up being routinely
2473 * off-the-mark, we may need to dynamically readjust this
2474 * based on past performance.
2475 */
2476 uintptr_t hashsize = (buf->dtb_size >> 3) / sizeof (uintptr_t);
2477
2478 if ((uintptr_t)agb - hashsize * sizeof (dtrace_aggkey_t *) <
2479 (uintptr_t)tomax || hashsize == 0) {
2480 /*
2481 * We've been given a ludicrously small buffer;
2482 * increment our drop count and leave.
2483 */
2484 dtrace_buffer_drop(buf);
2485 return;
2486 }
2487
2488 /*
2489 * And now, a pathetic attempt to try to get a an odd (or
2490 * perchance, a prime) hash size for better hash distribution.
2491 */
2492 if (hashsize > (DTRACE_AGGHASHSIZE_SLEW << 3))
2493 hashsize -= DTRACE_AGGHASHSIZE_SLEW;
2494
2495 agb->dtagb_hashsize = hashsize;
2496 agb->dtagb_hash = (dtrace_aggkey_t **)((uintptr_t)agb -
2497 agb->dtagb_hashsize * sizeof (dtrace_aggkey_t *));
2498 agb->dtagb_free = (uintptr_t)agb->dtagb_hash;
2499
2500 for (i = 0; i < agb->dtagb_hashsize; i++)
2501 agb->dtagb_hash[i] = NULL;
2502 }
2503
2504 ASSERT(agg->dtag_first != NULL);
2505 ASSERT(agg->dtag_first->dta_intuple);
2506
2507 /*
2508 * Calculate the hash value based on the key. Note that we _don't_
2509 * include the aggid in the hashing (but we will store it as part of
2510 * the key). The hashing algorithm is Bob Jenkins' "One-at-a-time"
2511 * algorithm: a simple, quick algorithm that has no known funnels, and
2512 * gets good distribution in practice. The efficacy of the hashing
2513 * algorithm (and a comparison with other algorithms) may be found by
2514 * running the ::dtrace_aggstat MDB dcmd.
2515 */
2516 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2517 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2518 limit = i + act->dta_rec.dtrd_size;
2519 ASSERT(limit <= size);
2520 isstr = DTRACEACT_ISSTRING(act);
2521
2522 for (; i < limit; i++) {
2523 hashval += data[i];
2524 hashval += (hashval << 10);
2525 hashval ^= (hashval >> 6);
2526
2527 if (isstr && data[i] == '\0')
2528 break;
2529 }
2530 }
2531
2532 hashval += (hashval << 3);
2533 hashval ^= (hashval >> 11);
2534 hashval += (hashval << 15);
2535
2536 /*
2537 * Yes, the divide here is expensive -- but it's generally the least
2538 * of the performance issues given the amount of data that we iterate
2539 * over to compute hash values, compare data, etc.
2540 */
2541 ndx = hashval % agb->dtagb_hashsize;
2542
2543 for (key = agb->dtagb_hash[ndx]; key != NULL; key = key->dtak_next) {
2544 ASSERT((caddr_t)key >= tomax);
2545 ASSERT((caddr_t)key < tomax + buf->dtb_size);
2546
2547 if (hashval != key->dtak_hashval || key->dtak_size != size)
2548 continue;
2549
2550 kdata = key->dtak_data;
2551 ASSERT(kdata >= tomax && kdata < tomax + buf->dtb_size);
2552
2553 for (act = agg->dtag_first; act->dta_intuple;
2554 act = act->dta_next) {
2555 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2556 limit = i + act->dta_rec.dtrd_size;
2557 ASSERT(limit <= size);
2558 isstr = DTRACEACT_ISSTRING(act);
2559
2560 for (; i < limit; i++) {
2561 if (kdata[i] != data[i])
2562 goto next;
2563
2564 if (isstr && data[i] == '\0')
2565 break;
2566 }
2567 }
2568
2569 if (action != key->dtak_action) {
2570 /*
2571 * We are aggregating on the same value in the same
2572 * aggregation with two different aggregating actions.
2573 * (This should have been picked up in the compiler,
2574 * so we may be dealing with errant or devious DIF.)
2575 * This is an error condition; we indicate as much,
2576 * and return.
2577 */
2578 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
2579 return;
2580 }
2581
2582 /*
2583 * This is a hit: we need to apply the aggregator to
2584 * the value at this key.
2585 */
2586 agg->dtag_aggregate((uint64_t *)(kdata + size), expr, arg);
2587 return;
2588 next:
2589 continue;
2590 }
2591
2592 /*
2593 * We didn't find it. We need to allocate some zero-filled space,
2594 * link it into the hash table appropriately, and apply the aggregator
2595 * to the (zero-filled) value.
2596 */
2597 offs = buf->dtb_offset;
2598 while (offs & (align - 1))
2599 offs += sizeof (uint32_t);
2600
2601 /*
2602 * If we don't have enough room to both allocate a new key _and_
2603 * its associated data, increment the drop count and return.
2604 */
2605 if ((uintptr_t)tomax + offs + fsize >
2606 agb->dtagb_free - sizeof (dtrace_aggkey_t)) {
2607 dtrace_buffer_drop(buf);
2608 return;
2609 }
2610
2611 /*CONSTCOND*/
2612 ASSERT(!(sizeof (dtrace_aggkey_t) & (sizeof (uintptr_t) - 1)));
2613 key = (dtrace_aggkey_t *)(agb->dtagb_free - sizeof (dtrace_aggkey_t));
2614 agb->dtagb_free -= sizeof (dtrace_aggkey_t);
2615
2616 key->dtak_data = kdata = tomax + offs;
2617 buf->dtb_offset = offs + fsize;
2618
2619 /*
2620 * Now copy the data across.
2621 */
2622 *((dtrace_aggid_t *)kdata) = agg->dtag_id;
2623
2624 for (i = sizeof (dtrace_aggid_t); i < size; i++)
2625 kdata[i] = data[i];
2626
2627 /*
2628 * Because strings are not zeroed out by default, we need to iterate
2629 * looking for actions that store strings, and we need to explicitly
2630 * pad these strings out with zeroes.
2631 */
2632 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2633 int nul;
2634
2635 if (!DTRACEACT_ISSTRING(act))
2636 continue;
2637
2638 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2639 limit = i + act->dta_rec.dtrd_size;
2640 ASSERT(limit <= size);
2641
2642 for (nul = 0; i < limit; i++) {
2643 if (nul) {
2644 kdata[i] = '\0';
2645 continue;
2646 }
2647
2648 if (data[i] != '\0')
2649 continue;
2650
2651 nul = 1;
2652 }
2653 }
2654
2655 for (i = size; i < fsize; i++)
2656 kdata[i] = 0;
2657
2658 key->dtak_hashval = hashval;
2659 key->dtak_size = size;
2660 key->dtak_action = action;
2661 key->dtak_next = agb->dtagb_hash[ndx];
2662 agb->dtagb_hash[ndx] = key;
2663
2664 /*
2665 * Finally, apply the aggregator.
2666 */
2667 *((uint64_t *)(key->dtak_data + size)) = agg->dtag_initial;
2668 agg->dtag_aggregate((uint64_t *)(key->dtak_data + size), expr, arg);
2669 }
2670
2671 /*
2672 * Given consumer state, this routine finds a speculation in the INACTIVE
2673 * state and transitions it into the ACTIVE state. If there is no speculation
2674 * in the INACTIVE state, 0 is returned. In this case, no error counter is
2675 * incremented -- it is up to the caller to take appropriate action.
2676 */
2677 static int
2678 dtrace_speculation(dtrace_state_t *state)
2679 {
2680 int i = 0;
2681 dtrace_speculation_state_t current;
2682 uint32_t *stat = &state->dts_speculations_unavail, count;
2683
2684 while (i < state->dts_nspeculations) {
2685 dtrace_speculation_t *spec = &state->dts_speculations[i];
2686
2687 current = spec->dtsp_state;
2688
2689 if (current != DTRACESPEC_INACTIVE) {
2690 if (current == DTRACESPEC_COMMITTINGMANY ||
2691 current == DTRACESPEC_COMMITTING ||
2692 current == DTRACESPEC_DISCARDING)
2693 stat = &state->dts_speculations_busy;
2694 i++;
2695 continue;
2696 }
2697
2698 if (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2699 current, DTRACESPEC_ACTIVE) == current)
2700 return (i + 1);
2701 }
2702
2703 /*
2704 * We couldn't find a speculation. If we found as much as a single
2705 * busy speculation buffer, we'll attribute this failure as "busy"
2706 * instead of "unavail".
2707 */
2708 do {
2709 count = *stat;
2710 } while (dtrace_cas32(stat, count, count + 1) != count);
2711
2712 return (0);
2713 }
2714
2715 /*
2716 * This routine commits an active speculation. If the specified speculation
2717 * is not in a valid state to perform a commit(), this routine will silently do
2718 * nothing. The state of the specified speculation is transitioned according
2719 * to the state transition diagram outlined in <sys/dtrace_impl.h>
2720 */
2721 static void
2722 dtrace_speculation_commit(dtrace_state_t *state, processorid_t cpu,
2723 dtrace_specid_t which)
2724 {
2725 dtrace_speculation_t *spec;
2726 dtrace_buffer_t *src, *dest;
2727 uintptr_t daddr, saddr, dlimit, slimit;
2728 dtrace_speculation_state_t current, new;
2729 intptr_t offs;
2730 uint64_t timestamp;
2731
2732 if (which == 0)
2733 return;
2734
2735 if (which > state->dts_nspeculations) {
2736 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2737 return;
2738 }
2739
2740 spec = &state->dts_speculations[which - 1];
2741 src = &spec->dtsp_buffer[cpu];
2742 dest = &state->dts_buffer[cpu];
2743
2744 do {
2745 current = spec->dtsp_state;
2746
2747 if (current == DTRACESPEC_COMMITTINGMANY)
2748 break;
2749
2750 switch (current) {
2751 case DTRACESPEC_INACTIVE:
2752 case DTRACESPEC_DISCARDING:
2753 return;
2754
2755 case DTRACESPEC_COMMITTING:
2756 /*
2757 * This is only possible if we are (a) commit()'ing
2758 * without having done a prior speculate() on this CPU
2759 * and (b) racing with another commit() on a different
2760 * CPU. There's nothing to do -- we just assert that
2761 * our offset is 0.
2762 */
2763 ASSERT(src->dtb_offset == 0);
2764 return;
2765
2766 case DTRACESPEC_ACTIVE:
2767 new = DTRACESPEC_COMMITTING;
2768 break;
2769
2770 case DTRACESPEC_ACTIVEONE:
2771 /*
2772 * This speculation is active on one CPU. If our
2773 * buffer offset is non-zero, we know that the one CPU
2774 * must be us. Otherwise, we are committing on a
2775 * different CPU from the speculate(), and we must
2776 * rely on being asynchronously cleaned.
2777 */
2778 if (src->dtb_offset != 0) {
2779 new = DTRACESPEC_COMMITTING;
2780 break;
2781 }
2782 /*FALLTHROUGH*/
2783
2784 case DTRACESPEC_ACTIVEMANY:
2785 new = DTRACESPEC_COMMITTINGMANY;
2786 break;
2787
2788 default:
2789 ASSERT(0);
2790 }
2791 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2792 current, new) != current);
2793
2794 /*
2795 * We have set the state to indicate that we are committing this
2796 * speculation. Now reserve the necessary space in the destination
2797 * buffer.
2798 */
2799 if ((offs = dtrace_buffer_reserve(dest, src->dtb_offset,
2800 sizeof (uint64_t), state, NULL)) < 0) {
2801 dtrace_buffer_drop(dest);
2802 goto out;
2803 }
2804
2805 /*
2806 * We have sufficient space to copy the speculative buffer into the
2807 * primary buffer. First, modify the speculative buffer, filling
2808 * in the timestamp of all entries with the current time. The data
2809 * must have the commit() time rather than the time it was traced,
2810 * so that all entries in the primary buffer are in timestamp order.
2811 */
2812 timestamp = dtrace_gethrtime();
2813 saddr = (uintptr_t)src->dtb_tomax;
2814 slimit = saddr + src->dtb_offset;
2815 while (saddr < slimit) {
2816 size_t size;
2817 dtrace_rechdr_t *dtrh = (dtrace_rechdr_t *)saddr;
2818
2819 if (dtrh->dtrh_epid == DTRACE_EPIDNONE) {
2820 saddr += sizeof (dtrace_epid_t);
2821 continue;
2822 }
2823 ASSERT3U(dtrh->dtrh_epid, <=, state->dts_necbs);
2824 size = state->dts_ecbs[dtrh->dtrh_epid - 1]->dte_size;
2825
2826 ASSERT3U(saddr + size, <=, slimit);
2827 ASSERT3U(size, >=, sizeof (dtrace_rechdr_t));
2828 ASSERT3U(DTRACE_RECORD_LOAD_TIMESTAMP(dtrh), ==, UINT64_MAX);
2829
2830 DTRACE_RECORD_STORE_TIMESTAMP(dtrh, timestamp);
2831
2832 saddr += size;
2833 }
2834
2835 /*
2836 * Copy the buffer across. (Note that this is a
2837 * highly subobtimal bcopy(); in the unlikely event that this becomes
2838 * a serious performance issue, a high-performance DTrace-specific
2839 * bcopy() should obviously be invented.)
2840 */
2841 daddr = (uintptr_t)dest->dtb_tomax + offs;
2842 dlimit = daddr + src->dtb_offset;
2843 saddr = (uintptr_t)src->dtb_tomax;
2844
2845 /*
2846 * First, the aligned portion.
2847 */
2848 while (dlimit - daddr >= sizeof (uint64_t)) {
2849 *((uint64_t *)daddr) = *((uint64_t *)saddr);
2850
2851 daddr += sizeof (uint64_t);
2852 saddr += sizeof (uint64_t);
2853 }
2854
2855 /*
2856 * Now any left-over bit...
2857 */
2858 while (dlimit - daddr)
2859 *((uint8_t *)daddr++) = *((uint8_t *)saddr++);
2860
2861 /*
2862 * Finally, commit the reserved space in the destination buffer.
2863 */
2864 dest->dtb_offset = offs + src->dtb_offset;
2865
2866 out:
2867 /*
2868 * If we're lucky enough to be the only active CPU on this speculation
2869 * buffer, we can just set the state back to DTRACESPEC_INACTIVE.
2870 */
2871 if (current == DTRACESPEC_ACTIVE ||
2872 (current == DTRACESPEC_ACTIVEONE && new == DTRACESPEC_COMMITTING)) {
2873 uint32_t rval = dtrace_cas32((uint32_t *)&spec->dtsp_state,
2874 DTRACESPEC_COMMITTING, DTRACESPEC_INACTIVE);
2875
2876 ASSERT(rval == DTRACESPEC_COMMITTING);
2877 }
2878
2879 src->dtb_offset = 0;
2880 src->dtb_xamot_drops += src->dtb_drops;
2881 src->dtb_drops = 0;
2882 }
2883
2884 /*
2885 * This routine discards an active speculation. If the specified speculation
2886 * is not in a valid state to perform a discard(), this routine will silently
2887 * do nothing. The state of the specified speculation is transitioned
2888 * according to the state transition diagram outlined in <sys/dtrace_impl.h>
2889 */
2890 static void
2891 dtrace_speculation_discard(dtrace_state_t *state, processorid_t cpu,
2892 dtrace_specid_t which)
2893 {
2894 dtrace_speculation_t *spec;
2895 dtrace_speculation_state_t current, new;
2896 dtrace_buffer_t *buf;
2897
2898 if (which == 0)
2899 return;
2900
2901 if (which > state->dts_nspeculations) {
2902 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2903 return;
2904 }
2905
2906 spec = &state->dts_speculations[which - 1];
2907 buf = &spec->dtsp_buffer[cpu];
2908
2909 do {
2910 current = spec->dtsp_state;
2911
2912 switch (current) {
2913 case DTRACESPEC_INACTIVE:
2914 case DTRACESPEC_COMMITTINGMANY:
2915 case DTRACESPEC_COMMITTING:
2916 case DTRACESPEC_DISCARDING:
2917 return;
2918
2919 case DTRACESPEC_ACTIVE:
2920 case DTRACESPEC_ACTIVEMANY:
2921 new = DTRACESPEC_DISCARDING;
2922 break;
2923
2924 case DTRACESPEC_ACTIVEONE:
2925 if (buf->dtb_offset != 0) {
2926 new = DTRACESPEC_INACTIVE;
2927 } else {
2928 new = DTRACESPEC_DISCARDING;
2929 }
2930 break;
2931
2932 default:
2933 ASSERT(0);
2934 }
2935 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2936 current, new) != current);
2937
2938 buf->dtb_offset = 0;
2939 buf->dtb_drops = 0;
2940 }
2941
2942 /*
2943 * Note: not called from probe context. This function is called
2944 * asynchronously from cross call context to clean any speculations that are
2945 * in the COMMITTINGMANY or DISCARDING states. These speculations may not be
2946 * transitioned back to the INACTIVE state until all CPUs have cleaned the
2947 * speculation.
2948 */
2949 static void
2950 dtrace_speculation_clean_here(dtrace_state_t *state)
2951 {
2952 dtrace_icookie_t cookie;
2953 processorid_t cpu = CPU->cpu_id;
2954 dtrace_buffer_t *dest = &state->dts_buffer[cpu];
2955 dtrace_specid_t i;
2956
2957 cookie = dtrace_interrupt_disable();
2958
2959 if (dest->dtb_tomax == NULL) {
2960 dtrace_interrupt_enable(cookie);
2961 return;
2962 }
2963
2964 for (i = 0; i < state->dts_nspeculations; i++) {
2965 dtrace_speculation_t *spec = &state->dts_speculations[i];
2966 dtrace_buffer_t *src = &spec->dtsp_buffer[cpu];
2967
2968 if (src->dtb_tomax == NULL)
2969 continue;
2970
2971 if (spec->dtsp_state == DTRACESPEC_DISCARDING) {
2972 src->dtb_offset = 0;
2973 continue;
2974 }
2975
2976 if (spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2977 continue;
2978
2979 if (src->dtb_offset == 0)
2980 continue;
2981
2982 dtrace_speculation_commit(state, cpu, i + 1);
2983 }
2984
2985 dtrace_interrupt_enable(cookie);
2986 }
2987
2988 /*
2989 * Note: not called from probe context. This function is called
2990 * asynchronously (and at a regular interval) to clean any speculations that
2991 * are in the COMMITTINGMANY or DISCARDING states. If it discovers that there
2992 * is work to be done, it cross calls all CPUs to perform that work;
2993 * COMMITMANY and DISCARDING speculations may not be transitioned back to the
2994 * INACTIVE state until they have been cleaned by all CPUs.
2995 */
2996 static void
2997 dtrace_speculation_clean(dtrace_state_t *state)
2998 {
2999 int work = 0, rv;
3000 dtrace_specid_t i;
3001
3002 for (i = 0; i < state->dts_nspeculations; i++) {
3003 dtrace_speculation_t *spec = &state->dts_speculations[i];
3004
3005 ASSERT(!spec->dtsp_cleaning);
3006
3007 if (spec->dtsp_state != DTRACESPEC_DISCARDING &&
3008 spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
3009 continue;
3010
3011 work++;
3012 spec->dtsp_cleaning = 1;
3013 }
3014
3015 if (!work)
3016 return;
3017
3018 dtrace_xcall(DTRACE_CPUALL,
3019 (dtrace_xcall_t)dtrace_speculation_clean_here, state);
3020
3021 /*
3022 * We now know that all CPUs have committed or discarded their
3023 * speculation buffers, as appropriate. We can now set the state
3024 * to inactive.
3025 */
3026 for (i = 0; i < state->dts_nspeculations; i++) {
3027 dtrace_speculation_t *spec = &state->dts_speculations[i];
3028 dtrace_speculation_state_t current, new;
3029
3030 if (!spec->dtsp_cleaning)
3031 continue;
3032
3033 current = spec->dtsp_state;
3034 ASSERT(current == DTRACESPEC_DISCARDING ||
3035 current == DTRACESPEC_COMMITTINGMANY);
3036
3037 new = DTRACESPEC_INACTIVE;
3038
3039 rv = dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new);
3040 ASSERT(rv == current);
3041 spec->dtsp_cleaning = 0;
3042 }
3043 }
3044
3045 /*
3046 * Called as part of a speculate() to get the speculative buffer associated
3047 * with a given speculation. Returns NULL if the specified speculation is not
3048 * in an ACTIVE state. If the speculation is in the ACTIVEONE state -- and
3049 * the active CPU is not the specified CPU -- the speculation will be
3050 * atomically transitioned into the ACTIVEMANY state.
3051 */
3052 static dtrace_buffer_t *
3053 dtrace_speculation_buffer(dtrace_state_t *state, processorid_t cpuid,
3054 dtrace_specid_t which)
3055 {
3056 dtrace_speculation_t *spec;
3057 dtrace_speculation_state_t current, new;
3058 dtrace_buffer_t *buf;
3059
3060 if (which == 0)
3061 return (NULL);
3062
3063 if (which > state->dts_nspeculations) {
3064 cpu_core[cpuid].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
3065 return (NULL);
3066 }
3067
3068 spec = &state->dts_speculations[which - 1];
3069 buf = &spec->dtsp_buffer[cpuid];
3070
3071 do {
3072 current = spec->dtsp_state;
3073
3074 switch (current) {
3075 case DTRACESPEC_INACTIVE:
3076 case DTRACESPEC_COMMITTINGMANY:
3077 case DTRACESPEC_DISCARDING:
3078 return (NULL);
3079
3080 case DTRACESPEC_COMMITTING:
3081 ASSERT(buf->dtb_offset == 0);
3082 return (NULL);
3083
3084 case DTRACESPEC_ACTIVEONE:
3085 /*
3086 * This speculation is currently active on one CPU.
3087 * Check the offset in the buffer; if it's non-zero,
3088 * that CPU must be us (and we leave the state alone).
3089 * If it's zero, assume that we're starting on a new
3090 * CPU -- and change the state to indicate that the
3091 * speculation is active on more than one CPU.
3092 */
3093 if (buf->dtb_offset != 0)
3094 return (buf);
3095
3096 new = DTRACESPEC_ACTIVEMANY;
3097 break;
3098
3099 case DTRACESPEC_ACTIVEMANY:
3100 return (buf);
3101
3102 case DTRACESPEC_ACTIVE:
3103 new = DTRACESPEC_ACTIVEONE;
3104 break;
3105
3106 default:
3107 ASSERT(0);
3108 }
3109 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
3110 current, new) != current);
3111
3112 ASSERT(new == DTRACESPEC_ACTIVEONE || new == DTRACESPEC_ACTIVEMANY);
3113 return (buf);
3114 }
3115
3116 /*
3117 * Return a string. In the event that the user lacks the privilege to access
3118 * arbitrary kernel memory, we copy the string out to scratch memory so that we
3119 * don't fail access checking.
3120 *
3121 * dtrace_dif_variable() uses this routine as a helper for various
3122 * builtin values such as 'execname' and 'probefunc.'
3123 */
3124 uintptr_t
3125 dtrace_dif_varstr(uintptr_t addr, dtrace_state_t *state,
3126 dtrace_mstate_t *mstate)
3127 {
3128 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3129 uintptr_t ret;
3130 size_t strsz;
3131
3132 /*
3133 * The easy case: this probe is allowed to read all of memory, so
3134 * we can just return this as a vanilla pointer.
3135 */
3136 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
3137 return (addr);
3138
3139 /*
3140 * This is the tougher case: we copy the string in question from
3141 * kernel memory into scratch memory and return it that way: this
3142 * ensures that we won't trip up when access checking tests the
3143 * BYREF return value.
3144 */
3145 strsz = dtrace_strlen((char *)addr, size) + 1;
3146
3147 if (mstate->dtms_scratch_ptr + strsz >
3148 mstate->dtms_scratch_base + mstate->dtms_scratch_size) {
3149 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3150 return (0);
3151 }
3152
3153 dtrace_strcpy((const void *)addr, (void *)mstate->dtms_scratch_ptr,
3154 strsz);
3155 ret = mstate->dtms_scratch_ptr;
3156 mstate->dtms_scratch_ptr += strsz;
3157 return (ret);
3158 }
3159
3160 /*
3161 * This function implements the DIF emulator's variable lookups. The emulator
3162 * passes a reserved variable identifier and optional built-in array index.
3163 */
3164 static uint64_t
3165 dtrace_dif_variable(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t v,
3166 uint64_t ndx)
3167 {
3168 /*
3169 * If we're accessing one of the uncached arguments, we'll turn this
3170 * into a reference in the args array.
3171 */
3172 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) {
3173 ndx = v - DIF_VAR_ARG0;
3174 v = DIF_VAR_ARGS;
3175 }
3176
3177 switch (v) {
3178 case DIF_VAR_ARGS:
3179 if (!(mstate->dtms_access & DTRACE_ACCESS_ARGS)) {
3180 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |=
3181 CPU_DTRACE_KPRIV;
3182 return (0);
3183 }
3184
3185 ASSERT(mstate->dtms_present & DTRACE_MSTATE_ARGS);
3186 if (ndx >= sizeof (mstate->dtms_arg) /
3187 sizeof (mstate->dtms_arg[0])) {
3188 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3189 dtrace_provider_t *pv;
3190 uint64_t val;
3191
3192 pv = mstate->dtms_probe->dtpr_provider;
3193 if (pv->dtpv_pops.dtps_getargval != NULL)
3194 val = pv->dtpv_pops.dtps_getargval(pv->dtpv_arg,
3195 mstate->dtms_probe->dtpr_id,
3196 mstate->dtms_probe->dtpr_arg, ndx, aframes);
3197 else
3198 val = dtrace_getarg(ndx, aframes);
3199
3200 /*
3201 * This is regrettably required to keep the compiler
3202 * from tail-optimizing the call to dtrace_getarg().
3203 * The condition always evaluates to true, but the
3204 * compiler has no way of figuring that out a priori.
3205 * (None of this would be necessary if the compiler
3206 * could be relied upon to _always_ tail-optimize
3207 * the call to dtrace_getarg() -- but it can't.)
3208 */
3209 if (mstate->dtms_probe != NULL)
3210 return (val);
3211
3212 ASSERT(0);
3213 }
3214
3215 return (mstate->dtms_arg[ndx]);
3216
3217 case DIF_VAR_UREGS: {
3218 klwp_t *lwp;
3219
3220 if (!dtrace_priv_proc(state, mstate))
3221 return (0);
3222
3223 if ((lwp = curthread->t_lwp) == NULL) {
3224 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
3225 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = 0;
3226 return (0);
3227 }
3228
3229 return (dtrace_getreg(lwp->lwp_regs, ndx));
3230 }
3231
3232 case DIF_VAR_VMREGS: {
3233 uint64_t rval;
3234
3235 if (!dtrace_priv_kernel(state))
3236 return (0);
3237
3238 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3239
3240 rval = dtrace_getvmreg(ndx,
3241 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags);
3242
3243 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3244
3245 return (rval);
3246 }
3247
3248 case DIF_VAR_CURTHREAD:
3249 if (!dtrace_priv_proc(state, mstate))
3250 return (0);
3251 return ((uint64_t)(uintptr_t)curthread);
3252
3253 case DIF_VAR_TIMESTAMP:
3254 if (!(mstate->dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
3255 mstate->dtms_timestamp = dtrace_gethrtime();
3256 mstate->dtms_present |= DTRACE_MSTATE_TIMESTAMP;
3257 }
3258 return (mstate->dtms_timestamp);
3259
3260 case DIF_VAR_VTIMESTAMP:
3261 ASSERT(dtrace_vtime_references != 0);
3262 return (curthread->t_dtrace_vtime);
3263
3264 case DIF_VAR_WALLTIMESTAMP:
3265 if (!(mstate->dtms_present & DTRACE_MSTATE_WALLTIMESTAMP)) {
3266 mstate->dtms_walltimestamp = dtrace_gethrestime();
3267 mstate->dtms_present |= DTRACE_MSTATE_WALLTIMESTAMP;
3268 }
3269 return (mstate->dtms_walltimestamp);
3270
3271 case DIF_VAR_IPL:
3272 if (!dtrace_priv_kernel(state))
3273 return (0);
3274 if (!(mstate->dtms_present & DTRACE_MSTATE_IPL)) {
3275 mstate->dtms_ipl = dtrace_getipl();
3276 mstate->dtms_present |= DTRACE_MSTATE_IPL;
3277 }
3278 return (mstate->dtms_ipl);
3279
3280 case DIF_VAR_EPID:
3281 ASSERT(mstate->dtms_present & DTRACE_MSTATE_EPID);
3282 return (mstate->dtms_epid);
3283
3284 case DIF_VAR_ID:
3285 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3286 return (mstate->dtms_probe->dtpr_id);
3287
3288 case DIF_VAR_STACKDEPTH:
3289 if (!dtrace_priv_kernel(state))
3290 return (0);
3291 if (!(mstate->dtms_present & DTRACE_MSTATE_STACKDEPTH)) {
3292 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3293
3294 mstate->dtms_stackdepth = dtrace_getstackdepth(aframes);
3295 mstate->dtms_present |= DTRACE_MSTATE_STACKDEPTH;
3296 }
3297 return (mstate->dtms_stackdepth);
3298
3299 case DIF_VAR_USTACKDEPTH:
3300 if (!dtrace_priv_proc(state, mstate))
3301 return (0);
3302 if (!(mstate->dtms_present & DTRACE_MSTATE_USTACKDEPTH)) {
3303 /*
3304 * See comment in DIF_VAR_PID.
3305 */
3306 if (DTRACE_ANCHORED(mstate->dtms_probe) &&
3307 CPU_ON_INTR(CPU)) {
3308 mstate->dtms_ustackdepth = 0;
3309 } else {
3310 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3311 mstate->dtms_ustackdepth =
3312 dtrace_getustackdepth();
3313 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3314 }
3315 mstate->dtms_present |= DTRACE_MSTATE_USTACKDEPTH;
3316 }
3317 return (mstate->dtms_ustackdepth);
3318
3319 case DIF_VAR_CALLER:
3320 if (!dtrace_priv_kernel(state))
3321 return (0);
3322 if (!(mstate->dtms_present & DTRACE_MSTATE_CALLER)) {
3323 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3324
3325 if (!DTRACE_ANCHORED(mstate->dtms_probe)) {
3326 /*
3327 * If this is an unanchored probe, we are
3328 * required to go through the slow path:
3329 * dtrace_caller() only guarantees correct
3330 * results for anchored probes.
3331 */
3332 pc_t caller[2];
3333
3334 dtrace_getpcstack(caller, 2, aframes,
3335 (uint32_t *)(uintptr_t)mstate->dtms_arg[0]);
3336 mstate->dtms_caller = caller[1];
3337 } else if ((mstate->dtms_caller =
3338 dtrace_caller(aframes)) == -1) {
3339 /*
3340 * We have failed to do this the quick way;
3341 * we must resort to the slower approach of
3342 * calling dtrace_getpcstack().
3343 */
3344 pc_t caller;
3345
3346 dtrace_getpcstack(&caller, 1, aframes, NULL);
3347 mstate->dtms_caller = caller;
3348 }
3349
3350 mstate->dtms_present |= DTRACE_MSTATE_CALLER;
3351 }
3352 return (mstate->dtms_caller);
3353
3354 case DIF_VAR_UCALLER:
3355 if (!dtrace_priv_proc(state, mstate))
3356 return (0);
3357
3358 if (!(mstate->dtms_present & DTRACE_MSTATE_UCALLER)) {
3359 uint64_t ustack[3];
3360
3361 /*
3362 * dtrace_getupcstack() fills in the first uint64_t
3363 * with the current PID. The second uint64_t will
3364 * be the program counter at user-level. The third
3365 * uint64_t will contain the caller, which is what
3366 * we're after.
3367 */
3368 ustack[2] = 0;
3369 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3370 dtrace_getupcstack(ustack, 3);
3371 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3372 mstate->dtms_ucaller = ustack[2];
3373 mstate->dtms_present |= DTRACE_MSTATE_UCALLER;
3374 }
3375
3376 return (mstate->dtms_ucaller);
3377
3378 case DIF_VAR_PROBEPROV:
3379 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3380 return (dtrace_dif_varstr(
3381 (uintptr_t)mstate->dtms_probe->dtpr_provider->dtpv_name,
3382 state, mstate));
3383
3384 case DIF_VAR_PROBEMOD:
3385 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3386 return (dtrace_dif_varstr(
3387 (uintptr_t)mstate->dtms_probe->dtpr_mod,
3388 state, mstate));
3389
3390 case DIF_VAR_PROBEFUNC:
3391 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3392 return (dtrace_dif_varstr(
3393 (uintptr_t)mstate->dtms_probe->dtpr_func,
3394 state, mstate));
3395
3396 case DIF_VAR_PROBENAME:
3397 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3398 return (dtrace_dif_varstr(
3399 (uintptr_t)mstate->dtms_probe->dtpr_name,
3400 state, mstate));
3401
3402 case DIF_VAR_PID:
3403 if (!dtrace_priv_proc(state, mstate))
3404 return (0);
3405
3406 /*
3407 * Note that we are assuming that an unanchored probe is
3408 * always due to a high-level interrupt. (And we're assuming
3409 * that there is only a single high level interrupt.)
3410 */
3411 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3412 return (pid0.pid_id);
3413
3414 /*
3415 * It is always safe to dereference one's own t_procp pointer:
3416 * it always points to a valid, allocated proc structure.
3417 * Further, it is always safe to dereference the p_pidp member
3418 * of one's own proc structure. (These are truisms becuase
3419 * threads and processes don't clean up their own state --
3420 * they leave that task to whomever reaps them.)
3421 */
3422 return ((uint64_t)curthread->t_procp->p_pidp->pid_id);
3423
3424 case DIF_VAR_PPID:
3425 if (!dtrace_priv_proc(state, mstate))
3426 return (0);
3427
3428 /*
3429 * See comment in DIF_VAR_PID.
3430 */
3431 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3432 return (pid0.pid_id);
3433
3434 /*
3435 * It is always safe to dereference one's own t_procp pointer:
3436 * it always points to a valid, allocated proc structure.
3437 * (This is true because threads don't clean up their own
3438 * state -- they leave that task to whomever reaps them.)
3439 */
3440 return ((uint64_t)curthread->t_procp->p_ppid);
3441
3442 case DIF_VAR_TID:
3443 /*
3444 * See comment in DIF_VAR_PID.
3445 */
3446 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3447 return (0);
3448
3449 return ((uint64_t)curthread->t_tid);
3450
3451 case DIF_VAR_EXECNAME:
3452 if (!dtrace_priv_proc(state, mstate))
3453 return (0);
3454
3455 /*
3456 * See comment in DIF_VAR_PID.
3457 */
3458 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3459 return ((uint64_t)(uintptr_t)p0.p_user.u_comm);
3460
3461 /*
3462 * It is always safe to dereference one's own t_procp pointer:
3463 * it always points to a valid, allocated proc structure.
3464 * (This is true because threads don't clean up their own
3465 * state -- they leave that task to whomever reaps them.)
3466 */
3467 return (dtrace_dif_varstr(
3468 (uintptr_t)curthread->t_procp->p_user.u_comm,
3469 state, mstate));
3470
3471 case DIF_VAR_ZONENAME:
3472 if (!dtrace_priv_proc(state, mstate))
3473 return (0);
3474
3475 /*
3476 * See comment in DIF_VAR_PID.
3477 */
3478 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3479 return ((uint64_t)(uintptr_t)p0.p_zone->zone_name);
3480
3481 /*
3482 * It is always safe to dereference one's own t_procp pointer:
3483 * it always points to a valid, allocated proc structure.
3484 * (This is true because threads don't clean up their own
3485 * state -- they leave that task to whomever reaps them.)
3486 */
3487 return (dtrace_dif_varstr(
3488 (uintptr_t)curthread->t_procp->p_zone->zone_name,
3489 state, mstate));
3490
3491 case DIF_VAR_UID:
3492 if (!dtrace_priv_proc(state, mstate))
3493 return (0);
3494
3495 /*
3496 * See comment in DIF_VAR_PID.
3497 */
3498 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3499 return ((uint64_t)p0.p_cred->cr_uid);
3500
3501 /*
3502 * It is always safe to dereference one's own t_procp pointer:
3503 * it always points to a valid, allocated proc structure.
3504 * (This is true because threads don't clean up their own
3505 * state -- they leave that task to whomever reaps them.)
3506 *
3507 * Additionally, it is safe to dereference one's own process
3508 * credential, since this is never NULL after process birth.
3509 */
3510 return ((uint64_t)curthread->t_procp->p_cred->cr_uid);
3511
3512 case DIF_VAR_GID:
3513 if (!dtrace_priv_proc(state, mstate))
3514 return (0);
3515
3516 /*
3517 * See comment in DIF_VAR_PID.
3518 */
3519 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3520 return ((uint64_t)p0.p_cred->cr_gid);
3521
3522 /*
3523 * It is always safe to dereference one's own t_procp pointer:
3524 * it always points to a valid, allocated proc structure.
3525 * (This is true because threads don't clean up their own
3526 * state -- they leave that task to whomever reaps them.)
3527 *
3528 * Additionally, it is safe to dereference one's own process
3529 * credential, since this is never NULL after process birth.
3530 */
3531 return ((uint64_t)curthread->t_procp->p_cred->cr_gid);
3532
3533 case DIF_VAR_ERRNO: {
3534 klwp_t *lwp;
3535 if (!dtrace_priv_proc(state, mstate))
3536 return (0);
3537
3538 /*
3539 * See comment in DIF_VAR_PID.
3540 */
3541 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3542 return (0);
3543
3544 /*
3545 * It is always safe to dereference one's own t_lwp pointer in
3546 * the event that this pointer is non-NULL. (This is true
3547 * because threads and lwps don't clean up their own state --
3548 * they leave that task to whomever reaps them.)
3549 */
3550 if ((lwp = curthread->t_lwp) == NULL)
3551 return (0);
3552
3553 return ((uint64_t)lwp->lwp_errno);
3554 }
3555
3556 case DIF_VAR_THREADNAME:
3557 /*
3558 * See comment in DIF_VAR_PID.
3559 */
3560 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3561 return (0);
3562
3563 if (curthread->t_name == NULL)
3564 return (0);
3565
3566 /*
3567 * Once set, ->t_name itself is never changed: any updates are
3568 * made to the same buffer that we are pointing out. So we are
3569 * safe to dereference it here.
3570 */
3571 return (dtrace_dif_varstr((uintptr_t)curthread->t_name,
3572 state, mstate));
3573
3574 default:
3575 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
3576 return (0);
3577 }
3578 }
3579
3580 static void
3581 dtrace_dif_variable_write(dtrace_mstate_t *mstate, dtrace_state_t *state,
3582 uint64_t v, uint64_t ndx, uint64_t data)
3583 {
3584 switch (v) {
3585 case DIF_VAR_UREGS: {
3586 klwp_t *lwp;
3587
3588 if (dtrace_destructive_disallow ||
3589 !dtrace_priv_proc_control(state, mstate)) {
3590 return;
3591 }
3592
3593 if ((lwp = curthread->t_lwp) == NULL) {
3594 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
3595 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = 0;
3596 return;
3597 }
3598
3599 dtrace_setreg(lwp->lwp_regs, ndx, data);
3600 return;
3601 }
3602
3603 default:
3604 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
3605 return;
3606 }
3607 }
3608
3609 typedef enum dtrace_json_state {
3610 DTRACE_JSON_REST = 1,
3611 DTRACE_JSON_OBJECT,
3612 DTRACE_JSON_STRING,
3613 DTRACE_JSON_STRING_ESCAPE,
3614 DTRACE_JSON_STRING_ESCAPE_UNICODE,
3615 DTRACE_JSON_COLON,
3616 DTRACE_JSON_COMMA,
3617 DTRACE_JSON_VALUE,
3618 DTRACE_JSON_IDENTIFIER,
3619 DTRACE_JSON_NUMBER,
3620 DTRACE_JSON_NUMBER_FRAC,
3621 DTRACE_JSON_NUMBER_EXP,
3622 DTRACE_JSON_COLLECT_OBJECT
3623 } dtrace_json_state_t;
3624
3625 /*
3626 * This function possesses just enough knowledge about JSON to extract a single
3627 * value from a JSON string and store it in the scratch buffer. It is able
3628 * to extract nested object values, and members of arrays by index.
3629 *
3630 * elemlist is a list of JSON keys, stored as packed NUL-terminated strings, to
3631 * be looked up as we descend into the object tree. e.g.
3632 *
3633 * foo[0].bar.baz[32] --> "foo" NUL "0" NUL "bar" NUL "baz" NUL "32" NUL
3634 * with nelems = 5.
3635 *
3636 * The run time of this function must be bounded above by strsize to limit the
3637 * amount of work done in probe context. As such, it is implemented as a
3638 * simple state machine, reading one character at a time using safe loads
3639 * until we find the requested element, hit a parsing error or run off the
3640 * end of the object or string.
3641 *
3642 * As there is no way for a subroutine to return an error without interrupting
3643 * clause execution, we simply return NULL in the event of a missing key or any
3644 * other error condition. Each NULL return in this function is commented with
3645 * the error condition it represents -- parsing or otherwise.
3646 *
3647 * The set of states for the state machine closely matches the JSON
3648 * specification (http://json.org/). Briefly:
3649 *
3650 * DTRACE_JSON_REST:
3651 * Skip whitespace until we find either a top-level Object, moving
3652 * to DTRACE_JSON_OBJECT; or an Array, moving to DTRACE_JSON_VALUE.
3653 *
3654 * DTRACE_JSON_OBJECT:
3655 * Locate the next key String in an Object. Sets a flag to denote
3656 * the next String as a key string and moves to DTRACE_JSON_STRING.
3657 *
3658 * DTRACE_JSON_COLON:
3659 * Skip whitespace until we find the colon that separates key Strings
3660 * from their values. Once found, move to DTRACE_JSON_VALUE.
3661 *
3662 * DTRACE_JSON_VALUE:
3663 * Detects the type of the next value (String, Number, Identifier, Object
3664 * or Array) and routes to the states that process that type. Here we also
3665 * deal with the element selector list if we are requested to traverse down
3666 * into the object tree.
3667 *
3668 * DTRACE_JSON_COMMA:
3669 * Skip whitespace until we find the comma that separates key-value pairs
3670 * in Objects (returning to DTRACE_JSON_OBJECT) or values in Arrays
3671 * (similarly DTRACE_JSON_VALUE). All following literal value processing
3672 * states return to this state at the end of their value, unless otherwise
3673 * noted.
3674 *
3675 * DTRACE_JSON_NUMBER, DTRACE_JSON_NUMBER_FRAC, DTRACE_JSON_NUMBER_EXP:
3676 * Processes a Number literal from the JSON, including any exponent
3677 * component that may be present. Numbers are returned as strings, which
3678 * may be passed to strtoll() if an integer is required.
3679 *
3680 * DTRACE_JSON_IDENTIFIER:
3681 * Processes a "true", "false" or "null" literal in the JSON.
3682 *
3683 * DTRACE_JSON_STRING, DTRACE_JSON_STRING_ESCAPE,
3684 * DTRACE_JSON_STRING_ESCAPE_UNICODE:
3685 * Processes a String literal from the JSON, whether the String denotes
3686 * a key, a value or part of a larger Object. Handles all escape sequences
3687 * present in the specification, including four-digit unicode characters,
3688 * but merely includes the escape sequence without converting it to the
3689 * actual escaped character. If the String is flagged as a key, we
3690 * move to DTRACE_JSON_COLON rather than DTRACE_JSON_COMMA.
3691 *
3692 * DTRACE_JSON_COLLECT_OBJECT:
3693 * This state collects an entire Object (or Array), correctly handling
3694 * embedded strings. If the full element selector list matches this nested
3695 * object, we return the Object in full as a string. If not, we use this
3696 * state to skip to the next value at this level and continue processing.
3697 *
3698 * NOTE: This function uses various macros from strtolctype.h to manipulate
3699 * digit values, etc -- these have all been checked to ensure they make
3700 * no additional function calls.
3701 */
3702 static char *
3703 dtrace_json(uint64_t size, uintptr_t json, char *elemlist, int nelems,
3704 char *dest)
3705 {
3706 dtrace_json_state_t state = DTRACE_JSON_REST;
3707 int64_t array_elem = INT64_MIN;
3708 int64_t array_pos = 0;
3709 uint8_t escape_unicount = 0;
3710 boolean_t string_is_key = B_FALSE;
3711 boolean_t collect_object = B_FALSE;
3712 boolean_t found_key = B_FALSE;
3713 boolean_t in_array = B_FALSE;
3714 uint32_t braces = 0, brackets = 0;
3715 char *elem = elemlist;
3716 char *dd = dest;
3717 uintptr_t cur;
3718
3719 for (cur = json; cur < json + size; cur++) {
3720 char cc = dtrace_load8(cur);
3721 if (cc == '\0')
3722 return (NULL);
3723
3724 switch (state) {
3725 case DTRACE_JSON_REST:
3726 if (isspace(cc))
3727 break;
3728
3729 if (cc == '{') {
3730 state = DTRACE_JSON_OBJECT;
3731 break;
3732 }
3733
3734 if (cc == '[') {
3735 in_array = B_TRUE;
3736 array_pos = 0;
3737 array_elem = dtrace_strtoll(elem, 10, size);
3738 found_key = array_elem == 0 ? B_TRUE : B_FALSE;
3739 state = DTRACE_JSON_VALUE;
3740 break;
3741 }
3742
3743 /*
3744 * ERROR: expected to find a top-level object or array.
3745 */
3746 return (NULL);
3747 case DTRACE_JSON_OBJECT:
3748 if (isspace(cc))
3749 break;
3750
3751 if (cc == '"') {
3752 state = DTRACE_JSON_STRING;
3753 string_is_key = B_TRUE;
3754 break;
3755 }
3756
3757 /*
3758 * ERROR: either the object did not start with a key
3759 * string, or we've run off the end of the object
3760 * without finding the requested key.
3761 */
3762 return (NULL);
3763 case DTRACE_JSON_STRING:
3764 if (cc == '\\') {
3765 *dd++ = '\\';
3766 state = DTRACE_JSON_STRING_ESCAPE;
3767 break;
3768 }
3769
3770 if (cc == '"') {
3771 if (collect_object) {
3772 /*
3773 * We don't reset the dest here, as
3774 * the string is part of a larger
3775 * object being collected.
3776 */
3777 *dd++ = cc;
3778 collect_object = B_FALSE;
3779 state = DTRACE_JSON_COLLECT_OBJECT;
3780 break;
3781 }
3782 *dd = '\0';
3783 dd = dest; /* reset string buffer */
3784 if (string_is_key) {
3785 if (dtrace_strncmp(dest, elem,
3786 size) == 0)
3787 found_key = B_TRUE;
3788 } else if (found_key) {
3789 if (nelems > 1) {
3790 /*
3791 * We expected an object, not
3792 * this string.
3793 */
3794 return (NULL);
3795 }
3796 return (dest);
3797 }
3798 state = string_is_key ? DTRACE_JSON_COLON :
3799 DTRACE_JSON_COMMA;
3800 string_is_key = B_FALSE;
3801 break;
3802 }
3803
3804 *dd++ = cc;
3805 break;
3806 case DTRACE_JSON_STRING_ESCAPE:
3807 *dd++ = cc;
3808 if (cc == 'u') {
3809 escape_unicount = 0;
3810 state = DTRACE_JSON_STRING_ESCAPE_UNICODE;
3811 } else {
3812 state = DTRACE_JSON_STRING;
3813 }
3814 break;
3815 case DTRACE_JSON_STRING_ESCAPE_UNICODE:
3816 if (!isxdigit(cc)) {
3817 /*
3818 * ERROR: invalid unicode escape, expected
3819 * four valid hexidecimal digits.
3820 */
3821 return (NULL);
3822 }
3823
3824 *dd++ = cc;
3825 if (++escape_unicount == 4)
3826 state = DTRACE_JSON_STRING;
3827 break;
3828 case DTRACE_JSON_COLON:
3829 if (isspace(cc))
3830 break;
3831
3832 if (cc == ':') {
3833 state = DTRACE_JSON_VALUE;
3834 break;
3835 }
3836
3837 /*
3838 * ERROR: expected a colon.
3839 */
3840 return (NULL);
3841 case DTRACE_JSON_COMMA:
3842 if (isspace(cc))
3843 break;
3844
3845 if (cc == ',') {
3846 if (in_array) {
3847 state = DTRACE_JSON_VALUE;
3848 if (++array_pos == array_elem)
3849 found_key = B_TRUE;
3850 } else {
3851 state = DTRACE_JSON_OBJECT;
3852 }
3853 break;
3854 }
3855
3856 /*
3857 * ERROR: either we hit an unexpected character, or
3858 * we reached the end of the object or array without
3859 * finding the requested key.
3860 */
3861 return (NULL);
3862 case DTRACE_JSON_IDENTIFIER:
3863 if (islower(cc)) {
3864 *dd++ = cc;
3865 break;
3866 }
3867
3868 *dd = '\0';
3869 dd = dest; /* reset string buffer */
3870
3871 if (dtrace_strncmp(dest, "true", 5) == 0 ||
3872 dtrace_strncmp(dest, "false", 6) == 0 ||
3873 dtrace_strncmp(dest, "null", 5) == 0) {
3874 if (found_key) {
3875 if (nelems > 1) {
3876 /*
3877 * ERROR: We expected an object,
3878 * not this identifier.
3879 */
3880 return (NULL);
3881 }
3882 return (dest);
3883 } else {
3884 cur--;
3885 state = DTRACE_JSON_COMMA;
3886 break;
3887 }
3888 }
3889
3890 /*
3891 * ERROR: we did not recognise the identifier as one
3892 * of those in the JSON specification.
3893 */
3894 return (NULL);
3895 case DTRACE_JSON_NUMBER:
3896 if (cc == '.') {
3897 *dd++ = cc;
3898 state = DTRACE_JSON_NUMBER_FRAC;
3899 break;
3900 }
3901
3902 if (cc == 'x' || cc == 'X') {
3903 /*
3904 * ERROR: specification explicitly excludes
3905 * hexidecimal or octal numbers.
3906 */
3907 return (NULL);
3908 }
3909
3910 /* FALLTHRU */
3911 case DTRACE_JSON_NUMBER_FRAC:
3912 if (cc == 'e' || cc == 'E') {
3913 *dd++ = cc;
3914 state = DTRACE_JSON_NUMBER_EXP;
3915 break;
3916 }
3917
3918 if (cc == '+' || cc == '-') {
3919 /*
3920 * ERROR: expect sign as part of exponent only.
3921 */
3922 return (NULL);
3923 }
3924 /* FALLTHRU */
3925 case DTRACE_JSON_NUMBER_EXP:
3926 if (isdigit(cc) || cc == '+' || cc == '-') {
3927 *dd++ = cc;
3928 break;
3929 }
3930
3931 *dd = '\0';
3932 dd = dest; /* reset string buffer */
3933 if (found_key) {
3934 if (nelems > 1) {
3935 /*
3936 * ERROR: We expected an object, not
3937 * this number.
3938 */
3939 return (NULL);
3940 }
3941 return (dest);
3942 }
3943
3944 cur--;
3945 state = DTRACE_JSON_COMMA;
3946 break;
3947 case DTRACE_JSON_VALUE:
3948 if (isspace(cc))
3949 break;
3950
3951 if (cc == '{' || cc == '[') {
3952 if (nelems > 1 && found_key) {
3953 in_array = cc == '[' ? B_TRUE : B_FALSE;
3954 /*
3955 * If our element selector directs us
3956 * to descend into this nested object,
3957 * then move to the next selector
3958 * element in the list and restart the
3959 * state machine.
3960 */
3961 while (*elem != '\0')
3962 elem++;
3963 elem++; /* skip the inter-element NUL */
3964 nelems--;
3965 dd = dest;
3966 if (in_array) {
3967 state = DTRACE_JSON_VALUE;
3968 array_pos = 0;
3969 array_elem = dtrace_strtoll(
3970 elem, 10, size);
3971 found_key = array_elem == 0 ?
3972 B_TRUE : B_FALSE;
3973 } else {
3974 found_key = B_FALSE;
3975 state = DTRACE_JSON_OBJECT;
3976 }
3977 break;
3978 }
3979
3980 /*
3981 * Otherwise, we wish to either skip this
3982 * nested object or return it in full.
3983 */
3984 if (cc == '[')
3985 brackets = 1;
3986 else
3987 braces = 1;
3988 *dd++ = cc;
3989 state = DTRACE_JSON_COLLECT_OBJECT;
3990 break;
3991 }
3992
3993 if (cc == '"') {
3994 state = DTRACE_JSON_STRING;
3995 break;
3996 }
3997
3998 if (islower(cc)) {
3999 /*
4000 * Here we deal with true, false and null.
4001 */
4002 *dd++ = cc;
4003 state = DTRACE_JSON_IDENTIFIER;
4004 break;
4005 }
4006
4007 if (cc == '-' || isdigit(cc)) {
4008 *dd++ = cc;
4009 state = DTRACE_JSON_NUMBER;
4010 break;
4011 }
4012
4013 /*
4014 * ERROR: unexpected character at start of value.
4015 */
4016 return (NULL);
4017 case DTRACE_JSON_COLLECT_OBJECT:
4018 if (cc == '\0')
4019 /*
4020 * ERROR: unexpected end of input.
4021 */
4022 return (NULL);
4023
4024 *dd++ = cc;
4025 if (cc == '"') {
4026 collect_object = B_TRUE;
4027 state = DTRACE_JSON_STRING;
4028 break;
4029 }
4030
4031 if (cc == ']') {
4032 if (brackets-- == 0) {
4033 /*
4034 * ERROR: unbalanced brackets.
4035 */
4036 return (NULL);
4037 }
4038 } else if (cc == '}') {
4039 if (braces-- == 0) {
4040 /*
4041 * ERROR: unbalanced braces.
4042 */
4043 return (NULL);
4044 }
4045 } else if (cc == '{') {
4046 braces++;
4047 } else if (cc == '[') {
4048 brackets++;
4049 }
4050
4051 if (brackets == 0 && braces == 0) {
4052 if (found_key) {
4053 *dd = '\0';
4054 return (dest);
4055 }
4056 dd = dest; /* reset string buffer */
4057 state = DTRACE_JSON_COMMA;
4058 }
4059 break;
4060 }
4061 }
4062 return (NULL);
4063 }
4064
4065 /*
4066 * Emulate the execution of DTrace ID subroutines invoked by the call opcode.
4067 * Notice that we don't bother validating the proper number of arguments or
4068 * their types in the tuple stack. This isn't needed because all argument
4069 * interpretation is safe because of our load safety -- the worst that can
4070 * happen is that a bogus program can obtain bogus results.
4071 */
4072 static void
4073 dtrace_dif_subr(uint_t subr, uint_t rd, uint64_t *regs,
4074 dtrace_key_t *tupregs, int nargs,
4075 dtrace_mstate_t *mstate, dtrace_state_t *state)
4076 {
4077 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
4078 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
4079 dtrace_vstate_t *vstate = &state->dts_vstate;
4080
4081 union {
4082 mutex_impl_t mi;
4083 uint64_t mx;
4084 } m;
4085
4086 union {
4087 krwlock_t ri;
4088 uintptr_t rw;
4089 } r;
4090
4091 switch (subr) {
4092 case DIF_SUBR_RAND:
4093 regs[rd] = (dtrace_gethrtime() * 2416 + 374441) % 1771875;
4094 break;
4095
4096 case DIF_SUBR_MUTEX_OWNED:
4097 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4098 mstate, vstate)) {
4099 regs[rd] = 0;
4100 break;
4101 }
4102
4103 m.mx = dtrace_load64(tupregs[0].dttk_value);
4104 if (MUTEX_TYPE_ADAPTIVE(&m.mi))
4105 regs[rd] = MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER;
4106 else
4107 regs[rd] = LOCK_HELD(&m.mi.m_spin.m_spinlock);
4108 break;
4109
4110 case DIF_SUBR_MUTEX_OWNER:
4111 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4112 mstate, vstate)) {
4113 regs[rd] = 0;
4114 break;
4115 }
4116
4117 m.mx = dtrace_load64(tupregs[0].dttk_value);
4118 if (MUTEX_TYPE_ADAPTIVE(&m.mi) &&
4119 MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER)
4120 regs[rd] = (uintptr_t)MUTEX_OWNER(&m.mi);
4121 else
4122 regs[rd] = 0;
4123 break;
4124
4125 case DIF_SUBR_MUTEX_TYPE_ADAPTIVE:
4126 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4127 mstate, vstate)) {
4128 regs[rd] = 0;
4129 break;
4130 }
4131
4132 m.mx = dtrace_load64(tupregs[0].dttk_value);
4133 regs[rd] = MUTEX_TYPE_ADAPTIVE(&m.mi);
4134 break;
4135
4136 case DIF_SUBR_MUTEX_TYPE_SPIN:
4137 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4138 mstate, vstate)) {
4139 regs[rd] = 0;
4140 break;
4141 }
4142
4143 m.mx = dtrace_load64(tupregs[0].dttk_value);
4144 regs[rd] = MUTEX_TYPE_SPIN(&m.mi);
4145 break;
4146
4147 case DIF_SUBR_RW_READ_HELD: {
4148 uintptr_t tmp;
4149
4150 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t),
4151 mstate, vstate)) {
4152 regs[rd] = 0;
4153 break;
4154 }
4155
4156 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
4157 regs[rd] = _RW_READ_HELD(&r.ri, tmp);
4158 break;
4159 }
4160
4161 case DIF_SUBR_RW_WRITE_HELD:
4162 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
4163 mstate, vstate)) {
4164 regs[rd] = 0;
4165 break;
4166 }
4167
4168 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
4169 regs[rd] = _RW_WRITE_HELD(&r.ri);
4170 break;
4171
4172 case DIF_SUBR_RW_ISWRITER:
4173 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
4174 mstate, vstate)) {
4175 regs[rd] = 0;
4176 break;
4177 }
4178
4179 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
4180 regs[rd] = _RW_ISWRITER(&r.ri);
4181 break;
4182
4183 case DIF_SUBR_BCOPY: {
4184 /*
4185 * We need to be sure that the destination is in the scratch
4186 * region -- no other region is allowed.
4187 */
4188 uintptr_t src = tupregs[0].dttk_value;
4189 uintptr_t dest = tupregs[1].dttk_value;
4190 size_t size = tupregs[2].dttk_value;
4191
4192 if (!dtrace_inscratch(dest, size, mstate)) {
4193 *flags |= CPU_DTRACE_BADADDR;
4194 *illval = regs[rd];
4195 break;
4196 }
4197
4198 if (!dtrace_canload(src, size, mstate, vstate)) {
4199 regs[rd] = 0;
4200 break;
4201 }
4202
4203 dtrace_bcopy((void *)src, (void *)dest, size);
4204 break;
4205 }
4206
4207 case DIF_SUBR_ALLOCA:
4208 case DIF_SUBR_COPYIN: {
4209 uintptr_t dest = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
4210 uint64_t size =
4211 tupregs[subr == DIF_SUBR_ALLOCA ? 0 : 1].dttk_value;
4212 size_t scratch_size = (dest - mstate->dtms_scratch_ptr) + size;
4213
4214 /*
4215 * This action doesn't require any credential checks since
4216 * probes will not activate in user contexts to which the
4217 * enabling user does not have permissions.
4218 */
4219
4220 /*
4221 * Rounding up the user allocation size could have overflowed
4222 * a large, bogus allocation (like -1ULL) to 0.
4223 */
4224 if (scratch_size < size ||
4225 !DTRACE_INSCRATCH(mstate, scratch_size)) {
4226 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4227 regs[rd] = 0;
4228 break;
4229 }
4230
4231 if (subr == DIF_SUBR_COPYIN) {
4232 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4233 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
4234 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4235 }
4236
4237 mstate->dtms_scratch_ptr += scratch_size;
4238 regs[rd] = dest;
4239 break;
4240 }
4241
4242 case DIF_SUBR_COPYINTO: {
4243 uint64_t size = tupregs[1].dttk_value;
4244 uintptr_t dest = tupregs[2].dttk_value;
4245
4246 /*
4247 * This action doesn't require any credential checks since
4248 * probes will not activate in user contexts to which the
4249 * enabling user does not have permissions.
4250 */
4251 if (!dtrace_inscratch(dest, size, mstate)) {
4252 *flags |= CPU_DTRACE_BADADDR;
4253 *illval = regs[rd];
4254 break;
4255 }
4256
4257 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4258 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
4259 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4260 break;
4261 }
4262
4263 case DIF_SUBR_COPYINSTR: {
4264 uintptr_t dest = mstate->dtms_scratch_ptr;
4265 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4266
4267 if (nargs > 1 && tupregs[1].dttk_value < size)
4268 size = tupregs[1].dttk_value + 1;
4269
4270 /*
4271 * This action doesn't require any credential checks since
4272 * probes will not activate in user contexts to which the
4273 * enabling user does not have permissions.
4274 */
4275 if (!DTRACE_INSCRATCH(mstate, size)) {
4276 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4277 regs[rd] = 0;
4278 break;
4279 }
4280
4281 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4282 dtrace_copyinstr(tupregs[0].dttk_value, dest, size, flags);
4283 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4284
4285 ((char *)dest)[size - 1] = '\0';
4286 mstate->dtms_scratch_ptr += size;
4287 regs[rd] = dest;
4288 break;
4289 }
4290
4291 case DIF_SUBR_MSGSIZE:
4292 case DIF_SUBR_MSGDSIZE: {
4293 uintptr_t baddr = tupregs[0].dttk_value, daddr;
4294 uintptr_t wptr, rptr;
4295 size_t count = 0;
4296 int cont = 0;
4297
4298 while (baddr != 0 && !(*flags & CPU_DTRACE_FAULT)) {
4299
4300 if (!dtrace_canload(baddr, sizeof (mblk_t), mstate,
4301 vstate)) {
4302 regs[rd] = 0;
4303 break;
4304 }
4305
4306 wptr = dtrace_loadptr(baddr +
4307 offsetof(mblk_t, b_wptr));
4308
4309 rptr = dtrace_loadptr(baddr +
4310 offsetof(mblk_t, b_rptr));
4311
4312 if (wptr < rptr) {
4313 *flags |= CPU_DTRACE_BADADDR;
4314 *illval = tupregs[0].dttk_value;
4315 break;
4316 }
4317
4318 daddr = dtrace_loadptr(baddr +
4319 offsetof(mblk_t, b_datap));
4320
4321 baddr = dtrace_loadptr(baddr +
4322 offsetof(mblk_t, b_cont));
4323
4324 /*
4325 * We want to prevent against denial-of-service here,
4326 * so we're only going to search the list for
4327 * dtrace_msgdsize_max mblks.
4328 */
4329 if (cont++ > dtrace_msgdsize_max) {
4330 *flags |= CPU_DTRACE_ILLOP;
4331 break;
4332 }
4333
4334 if (subr == DIF_SUBR_MSGDSIZE) {
4335 if (dtrace_load8(daddr +
4336 offsetof(dblk_t, db_type)) != M_DATA)
4337 continue;
4338 }
4339
4340 count += wptr - rptr;
4341 }
4342
4343 if (!(*flags & CPU_DTRACE_FAULT))
4344 regs[rd] = count;
4345
4346 break;
4347 }
4348
4349 case DIF_SUBR_PROGENYOF: {
4350 pid_t pid = tupregs[0].dttk_value;
4351 proc_t *p;
4352 int rval = 0;
4353
4354 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4355
4356 for (p = curthread->t_procp; p != NULL; p = p->p_parent) {
4357 if (p->p_pidp->pid_id == pid) {
4358 rval = 1;
4359 break;
4360 }
4361 }
4362
4363 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4364
4365 regs[rd] = rval;
4366 break;
4367 }
4368
4369 case DIF_SUBR_SPECULATION:
4370 regs[rd] = dtrace_speculation(state);
4371 break;
4372
4373 case DIF_SUBR_COPYOUT: {
4374 uintptr_t kaddr = tupregs[0].dttk_value;
4375 uintptr_t uaddr = tupregs[1].dttk_value;
4376 uint64_t size = tupregs[2].dttk_value;
4377
4378 if (!dtrace_destructive_disallow &&
4379 dtrace_priv_proc_control(state, mstate) &&
4380 !dtrace_istoxic(kaddr, size) &&
4381 dtrace_canload(kaddr, size, mstate, vstate)) {
4382 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4383 dtrace_copyout(kaddr, uaddr, size, flags);
4384 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4385 }
4386 break;
4387 }
4388
4389 case DIF_SUBR_COPYOUTSTR: {
4390 uintptr_t kaddr = tupregs[0].dttk_value;
4391 uintptr_t uaddr = tupregs[1].dttk_value;
4392 uint64_t size = tupregs[2].dttk_value;
4393 size_t lim;
4394
4395 if (!dtrace_destructive_disallow &&
4396 dtrace_priv_proc_control(state, mstate) &&
4397 !dtrace_istoxic(kaddr, size) &&
4398 dtrace_strcanload(kaddr, size, &lim, mstate, vstate)) {
4399 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4400 dtrace_copyoutstr(kaddr, uaddr, lim, flags);
4401 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4402 }
4403 break;
4404 }
4405
4406 case DIF_SUBR_STRLEN: {
4407 size_t size = state->dts_options[DTRACEOPT_STRSIZE];
4408 uintptr_t addr = (uintptr_t)tupregs[0].dttk_value;
4409 size_t lim;
4410
4411 if (!dtrace_strcanload(addr, size, &lim, mstate, vstate)) {
4412 regs[rd] = 0;
4413 break;
4414 }
4415 regs[rd] = dtrace_strlen((char *)addr, lim);
4416
4417 break;
4418 }
4419
4420 case DIF_SUBR_STRCHR:
4421 case DIF_SUBR_STRRCHR: {
4422 /*
4423 * We're going to iterate over the string looking for the
4424 * specified character. We will iterate until we have reached
4425 * the string length or we have found the character. If this
4426 * is DIF_SUBR_STRRCHR, we will look for the last occurrence
4427 * of the specified character instead of the first.
4428 */
4429 uintptr_t addr = tupregs[0].dttk_value;
4430 uintptr_t addr_limit;
4431 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4432 size_t lim;
4433 char c, target = (char)tupregs[1].dttk_value;
4434
4435 if (!dtrace_strcanload(addr, size, &lim, mstate, vstate)) {
4436 regs[rd] = 0;
4437 break;
4438 }
4439 addr_limit = addr + lim;
4440
4441 for (regs[rd] = 0; addr < addr_limit; addr++) {
4442 if ((c = dtrace_load8(addr)) == target) {
4443 regs[rd] = addr;
4444
4445 if (subr == DIF_SUBR_STRCHR)
4446 break;
4447 }
4448 if (c == '\0')
4449 break;
4450 }
4451
4452 break;
4453 }
4454
4455 case DIF_SUBR_STRSTR:
4456 case DIF_SUBR_INDEX:
4457 case DIF_SUBR_RINDEX: {
4458 /*
4459 * We're going to iterate over the string looking for the
4460 * specified string. We will iterate until we have reached
4461 * the string length or we have found the string. (Yes, this
4462 * is done in the most naive way possible -- but considering
4463 * that the string we're searching for is likely to be
4464 * relatively short, the complexity of Rabin-Karp or similar
4465 * hardly seems merited.)
4466 */
4467 char *addr = (char *)(uintptr_t)tupregs[0].dttk_value;
4468 char *substr = (char *)(uintptr_t)tupregs[1].dttk_value;
4469 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4470 size_t len = dtrace_strlen(addr, size);
4471 size_t sublen = dtrace_strlen(substr, size);
4472 char *limit = addr + len, *orig = addr;
4473 int notfound = subr == DIF_SUBR_STRSTR ? 0 : -1;
4474 int inc = 1;
4475
4476 regs[rd] = notfound;
4477
4478 if (!dtrace_canload((uintptr_t)addr, len + 1, mstate, vstate)) {
4479 regs[rd] = 0;
4480 break;
4481 }
4482
4483 if (!dtrace_canload((uintptr_t)substr, sublen + 1, mstate,
4484 vstate)) {
4485 regs[rd] = 0;
4486 break;
4487 }
4488
4489 /*
4490 * strstr() and index()/rindex() have similar semantics if
4491 * both strings are the empty string: strstr() returns a
4492 * pointer to the (empty) string, and index() and rindex()
4493 * both return index 0 (regardless of any position argument).
4494 */
4495 if (sublen == 0 && len == 0) {
4496 if (subr == DIF_SUBR_STRSTR)
4497 regs[rd] = (uintptr_t)addr;
4498 else
4499 regs[rd] = 0;
4500 break;
4501 }
4502
4503 if (subr != DIF_SUBR_STRSTR) {
4504 if (subr == DIF_SUBR_RINDEX) {
4505 limit = orig - 1;
4506 addr += len;
4507 inc = -1;
4508 }
4509
4510 /*
4511 * Both index() and rindex() take an optional position
4512 * argument that denotes the starting position.
4513 */
4514 if (nargs == 3) {
4515 int64_t pos = (int64_t)tupregs[2].dttk_value;
4516
4517 /*
4518 * If the position argument to index() is
4519 * negative, Perl implicitly clamps it at
4520 * zero. This semantic is a little surprising
4521 * given the special meaning of negative
4522 * positions to similar Perl functions like
4523 * substr(), but it appears to reflect a
4524 * notion that index() can start from a
4525 * negative index and increment its way up to
4526 * the string. Given this notion, Perl's
4527 * rindex() is at least self-consistent in
4528 * that it implicitly clamps positions greater
4529 * than the string length to be the string
4530 * length. Where Perl completely loses
4531 * coherence, however, is when the specified
4532 * substring is the empty string (""). In
4533 * this case, even if the position is
4534 * negative, rindex() returns 0 -- and even if
4535 * the position is greater than the length,
4536 * index() returns the string length. These
4537 * semantics violate the notion that index()
4538 * should never return a value less than the
4539 * specified position and that rindex() should
4540 * never return a value greater than the
4541 * specified position. (One assumes that
4542 * these semantics are artifacts of Perl's
4543 * implementation and not the results of
4544 * deliberate design -- it beggars belief that
4545 * even Larry Wall could desire such oddness.)
4546 * While in the abstract one would wish for
4547 * consistent position semantics across
4548 * substr(), index() and rindex() -- or at the
4549 * very least self-consistent position
4550 * semantics for index() and rindex() -- we
4551 * instead opt to keep with the extant Perl
4552 * semantics, in all their broken glory. (Do
4553 * we have more desire to maintain Perl's
4554 * semantics than Perl does? Probably.)
4555 */
4556 if (subr == DIF_SUBR_RINDEX) {
4557 if (pos < 0) {
4558 if (sublen == 0)
4559 regs[rd] = 0;
4560 break;
4561 }
4562
4563 if (pos > len)
4564 pos = len;
4565 } else {
4566 if (pos < 0)
4567 pos = 0;
4568
4569 if (pos >= len) {
4570 if (sublen == 0)
4571 regs[rd] = len;
4572 break;
4573 }
4574 }
4575
4576 addr = orig + pos;
4577 }
4578 }
4579
4580 for (regs[rd] = notfound; addr != limit; addr += inc) {
4581 if (dtrace_strncmp(addr, substr, sublen) == 0) {
4582 if (subr != DIF_SUBR_STRSTR) {
4583 /*
4584 * As D index() and rindex() are
4585 * modeled on Perl (and not on awk),
4586 * we return a zero-based (and not a
4587 * one-based) index. (For you Perl
4588 * weenies: no, we're not going to add
4589 * $[ -- and shouldn't you be at a con
4590 * or something?)
4591 */
4592 regs[rd] = (uintptr_t)(addr - orig);
4593 break;
4594 }
4595
4596 ASSERT(subr == DIF_SUBR_STRSTR);
4597 regs[rd] = (uintptr_t)addr;
4598 break;
4599 }
4600 }
4601
4602 break;
4603 }
4604
4605 case DIF_SUBR_STRTOK: {
4606 uintptr_t addr = tupregs[0].dttk_value;
4607 uintptr_t tokaddr = tupregs[1].dttk_value;
4608 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4609 uintptr_t limit, toklimit;
4610 size_t clim;
4611 uint8_t c, tokmap[32]; /* 256 / 8 */
4612 char *dest = (char *)mstate->dtms_scratch_ptr;
4613 int i;
4614
4615 /*
4616 * Check both the token buffer and (later) the input buffer,
4617 * since both could be non-scratch addresses.
4618 */
4619 if (!dtrace_strcanload(tokaddr, size, &clim, mstate, vstate)) {
4620 regs[rd] = 0;
4621 break;
4622 }
4623 toklimit = tokaddr + clim;
4624
4625 if (!DTRACE_INSCRATCH(mstate, size)) {
4626 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4627 regs[rd] = 0;
4628 break;
4629 }
4630
4631 if (addr == 0) {
4632 /*
4633 * If the address specified is NULL, we use our saved
4634 * strtok pointer from the mstate. Note that this
4635 * means that the saved strtok pointer is _only_
4636 * valid within multiple enablings of the same probe --
4637 * it behaves like an implicit clause-local variable.
4638 */
4639 addr = mstate->dtms_strtok;
4640 limit = mstate->dtms_strtok_limit;
4641 } else {
4642 /*
4643 * If the user-specified address is non-NULL we must
4644 * access check it. This is the only time we have
4645 * a chance to do so, since this address may reside
4646 * in the string table of this clause-- future calls
4647 * (when we fetch addr from mstate->dtms_strtok)
4648 * would fail this access check.
4649 */
4650 if (!dtrace_strcanload(addr, size, &clim, mstate,
4651 vstate)) {
4652 regs[rd] = 0;
4653 break;
4654 }
4655 limit = addr + clim;
4656 }
4657
4658 /*
4659 * First, zero the token map, and then process the token
4660 * string -- setting a bit in the map for every character
4661 * found in the token string.
4662 */
4663 for (i = 0; i < sizeof (tokmap); i++)
4664 tokmap[i] = 0;
4665
4666 for (; tokaddr < toklimit; tokaddr++) {
4667 if ((c = dtrace_load8(tokaddr)) == '\0')
4668 break;
4669
4670 ASSERT((c >> 3) < sizeof (tokmap));
4671 tokmap[c >> 3] |= (1 << (c & 0x7));
4672 }
4673
4674 for (; addr < limit; addr++) {
4675 /*
4676 * We're looking for a character that is _not_
4677 * contained in the token string.
4678 */
4679 if ((c = dtrace_load8(addr)) == '\0')
4680 break;
4681
4682 if (!(tokmap[c >> 3] & (1 << (c & 0x7))))
4683 break;
4684 }
4685
4686 if (c == '\0') {
4687 /*
4688 * We reached the end of the string without finding
4689 * any character that was not in the token string.
4690 * We return NULL in this case, and we set the saved
4691 * address to NULL as well.
4692 */
4693 regs[rd] = 0;
4694 mstate->dtms_strtok = 0;
4695 mstate->dtms_strtok_limit = 0;
4696 break;
4697 }
4698
4699 /*
4700 * From here on, we're copying into the destination string.
4701 */
4702 for (i = 0; addr < limit && i < size - 1; addr++) {
4703 if ((c = dtrace_load8(addr)) == '\0')
4704 break;
4705
4706 if (tokmap[c >> 3] & (1 << (c & 0x7)))
4707 break;
4708
4709 ASSERT(i < size);
4710 dest[i++] = c;
4711 }
4712
4713 ASSERT(i < size);
4714 dest[i] = '\0';
4715 regs[rd] = (uintptr_t)dest;
4716 mstate->dtms_scratch_ptr += size;
4717 mstate->dtms_strtok = addr;
4718 mstate->dtms_strtok_limit = limit;
4719 break;
4720 }
4721
4722 case DIF_SUBR_SUBSTR: {
4723 uintptr_t s = tupregs[0].dttk_value;
4724 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4725 char *d = (char *)mstate->dtms_scratch_ptr;
4726 int64_t index = (int64_t)tupregs[1].dttk_value;
4727 int64_t remaining = (int64_t)tupregs[2].dttk_value;
4728 size_t len = dtrace_strlen((char *)s, size);
4729 int64_t i;
4730
4731 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
4732 regs[rd] = 0;
4733 break;
4734 }
4735
4736 if (!DTRACE_INSCRATCH(mstate, size)) {
4737 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4738 regs[rd] = 0;
4739 break;
4740 }
4741
4742 if (nargs <= 2)
4743 remaining = (int64_t)size;
4744
4745 if (index < 0) {
4746 index += len;
4747
4748 if (index < 0 && index + remaining > 0) {
4749 remaining += index;
4750 index = 0;
4751 }
4752 }
4753
4754 if (index >= len || index < 0) {
4755 remaining = 0;
4756 } else if (remaining < 0) {
4757 remaining += len - index;
4758 } else if (index + remaining > size) {
4759 remaining = size - index;
4760 }
4761
4762 for (i = 0; i < remaining; i++) {
4763 if ((d[i] = dtrace_load8(s + index + i)) == '\0')
4764 break;
4765 }
4766
4767 d[i] = '\0';
4768
4769 mstate->dtms_scratch_ptr += size;
4770 regs[rd] = (uintptr_t)d;
4771 break;
4772 }
4773
4774 case DIF_SUBR_JSON: {
4775 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4776 uintptr_t json = tupregs[0].dttk_value;
4777 size_t jsonlen = dtrace_strlen((char *)json, size);
4778 uintptr_t elem = tupregs[1].dttk_value;
4779 size_t elemlen = dtrace_strlen((char *)elem, size);
4780
4781 char *dest = (char *)mstate->dtms_scratch_ptr;
4782 char *elemlist = (char *)mstate->dtms_scratch_ptr + jsonlen + 1;
4783 char *ee = elemlist;
4784 int nelems = 1;
4785 uintptr_t cur;
4786
4787 if (!dtrace_canload(json, jsonlen + 1, mstate, vstate) ||
4788 !dtrace_canload(elem, elemlen + 1, mstate, vstate)) {
4789 regs[rd] = 0;
4790 break;
4791 }
4792
4793 if (!DTRACE_INSCRATCH(mstate, jsonlen + 1 + elemlen + 1)) {
4794 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4795 regs[rd] = 0;
4796 break;
4797 }
4798
4799 /*
4800 * Read the element selector and split it up into a packed list
4801 * of strings.
4802 */
4803 for (cur = elem; cur < elem + elemlen; cur++) {
4804 char cc = dtrace_load8(cur);
4805
4806 if (cur == elem && cc == '[') {
4807 /*
4808 * If the first element selector key is
4809 * actually an array index then ignore the
4810 * bracket.
4811 */
4812 continue;
4813 }
4814
4815 if (cc == ']')
4816 continue;
4817
4818 if (cc == '.' || cc == '[') {
4819 nelems++;
4820 cc = '\0';
4821 }
4822
4823 *ee++ = cc;
4824 }
4825 *ee++ = '\0';
4826
4827 if ((regs[rd] = (uintptr_t)dtrace_json(size, json, elemlist,
4828 nelems, dest)) != 0)
4829 mstate->dtms_scratch_ptr += jsonlen + 1;
4830 break;
4831 }
4832
4833 case DIF_SUBR_TOUPPER:
4834 case DIF_SUBR_TOLOWER: {
4835 uintptr_t s = tupregs[0].dttk_value;
4836 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4837 char *dest = (char *)mstate->dtms_scratch_ptr, c;
4838 size_t len = dtrace_strlen((char *)s, size);
4839 char lower, upper, convert;
4840 int64_t i;
4841
4842 if (subr == DIF_SUBR_TOUPPER) {
4843 lower = 'a';
4844 upper = 'z';
4845 convert = 'A';
4846 } else {
4847 lower = 'A';
4848 upper = 'Z';
4849 convert = 'a';
4850 }
4851
4852 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
4853 regs[rd] = 0;
4854 break;
4855 }
4856
4857 if (!DTRACE_INSCRATCH(mstate, size)) {
4858 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4859 regs[rd] = 0;
4860 break;
4861 }
4862
4863 for (i = 0; i < size - 1; i++) {
4864 if ((c = dtrace_load8(s + i)) == '\0')
4865 break;
4866
4867 if (c >= lower && c <= upper)
4868 c = convert + (c - lower);
4869
4870 dest[i] = c;
4871 }
4872
4873 ASSERT(i < size);
4874 dest[i] = '\0';
4875 regs[rd] = (uintptr_t)dest;
4876 mstate->dtms_scratch_ptr += size;
4877 break;
4878 }
4879
4880 case DIF_SUBR_GETMAJOR:
4881 #ifdef _LP64
4882 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR64) & MAXMAJ64;
4883 #else
4884 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR) & MAXMAJ;
4885 #endif
4886 break;
4887
4888 case DIF_SUBR_GETMINOR:
4889 #ifdef _LP64
4890 regs[rd] = tupregs[0].dttk_value & MAXMIN64;
4891 #else
4892 regs[rd] = tupregs[0].dttk_value & MAXMIN;
4893 #endif
4894 break;
4895
4896 case DIF_SUBR_DDI_PATHNAME: {
4897 /*
4898 * This one is a galactic mess. We are going to roughly
4899 * emulate ddi_pathname(), but it's made more complicated
4900 * by the fact that we (a) want to include the minor name and
4901 * (b) must proceed iteratively instead of recursively.
4902 */
4903 uintptr_t dest = mstate->dtms_scratch_ptr;
4904 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4905 char *start = (char *)dest, *end = start + size - 1;
4906 uintptr_t daddr = tupregs[0].dttk_value;
4907 int64_t minor = (int64_t)tupregs[1].dttk_value;
4908 char *s;
4909 int i, len, depth = 0;
4910
4911 /*
4912 * Due to all the pointer jumping we do and context we must
4913 * rely upon, we just mandate that the user must have kernel
4914 * read privileges to use this routine.
4915 */
4916 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) == 0) {
4917 *flags |= CPU_DTRACE_KPRIV;
4918 *illval = daddr;
4919 regs[rd] = 0;
4920 }
4921
4922 if (!DTRACE_INSCRATCH(mstate, size)) {
4923 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4924 regs[rd] = 0;
4925 break;
4926 }
4927
4928 *end = '\0';
4929
4930 /*
4931 * We want to have a name for the minor. In order to do this,
4932 * we need to walk the minor list from the devinfo. We want
4933 * to be sure that we don't infinitely walk a circular list,
4934 * so we check for circularity by sending a scout pointer
4935 * ahead two elements for every element that we iterate over;
4936 * if the list is circular, these will ultimately point to the
4937 * same element. You may recognize this little trick as the
4938 * answer to a stupid interview question -- one that always
4939 * seems to be asked by those who had to have it laboriously
4940 * explained to them, and who can't even concisely describe
4941 * the conditions under which one would be forced to resort to
4942 * this technique. Needless to say, those conditions are
4943 * found here -- and probably only here. Is this the only use
4944 * of this infamous trick in shipping, production code? If it
4945 * isn't, it probably should be...
4946 */
4947 if (minor != -1) {
4948 uintptr_t maddr = dtrace_loadptr(daddr +
4949 offsetof(struct dev_info, devi_minor));
4950
4951 uintptr_t next = offsetof(struct ddi_minor_data, next);
4952 uintptr_t name = offsetof(struct ddi_minor_data,
4953 d_minor) + offsetof(struct ddi_minor, name);
4954 uintptr_t dev = offsetof(struct ddi_minor_data,
4955 d_minor) + offsetof(struct ddi_minor, dev);
4956 uintptr_t scout;
4957
4958 if (maddr != 0)
4959 scout = dtrace_loadptr(maddr + next);
4960
4961 while (maddr != 0 && !(*flags & CPU_DTRACE_FAULT)) {
4962 uint64_t m;
4963 #ifdef _LP64
4964 m = dtrace_load64(maddr + dev) & MAXMIN64;
4965 #else
4966 m = dtrace_load32(maddr + dev) & MAXMIN;
4967 #endif
4968 if (m != minor) {
4969 maddr = dtrace_loadptr(maddr + next);
4970
4971 if (scout == 0)
4972 continue;
4973
4974 scout = dtrace_loadptr(scout + next);
4975
4976 if (scout == 0)
4977 continue;
4978
4979 scout = dtrace_loadptr(scout + next);
4980
4981 if (scout == 0)
4982 continue;
4983
4984 if (scout == maddr) {
4985 *flags |= CPU_DTRACE_ILLOP;
4986 break;
4987 }
4988
4989 continue;
4990 }
4991
4992 /*
4993 * We have the minor data. Now we need to
4994 * copy the minor's name into the end of the
4995 * pathname.
4996 */
4997 s = (char *)dtrace_loadptr(maddr + name);
4998 len = dtrace_strlen(s, size);
4999
5000 if (*flags & CPU_DTRACE_FAULT)
5001 break;
5002
5003 if (len != 0) {
5004 if ((end -= (len + 1)) < start)
5005 break;
5006
5007 *end = ':';
5008 }
5009
5010 for (i = 1; i <= len; i++)
5011 end[i] = dtrace_load8((uintptr_t)s++);
5012 break;
5013 }
5014 }
5015
5016 while (daddr != 0 && !(*flags & CPU_DTRACE_FAULT)) {
5017 ddi_node_state_t devi_state;
5018
5019 devi_state = dtrace_load32(daddr +
5020 offsetof(struct dev_info, devi_node_state));
5021
5022 if (*flags & CPU_DTRACE_FAULT)
5023 break;
5024
5025 if (devi_state >= DS_INITIALIZED) {
5026 s = (char *)dtrace_loadptr(daddr +
5027 offsetof(struct dev_info, devi_addr));
5028 len = dtrace_strlen(s, size);
5029
5030 if (*flags & CPU_DTRACE_FAULT)
5031 break;
5032
5033 if (len != 0) {
5034 if ((end -= (len + 1)) < start)
5035 break;
5036
5037 *end = '@';
5038 }
5039
5040 for (i = 1; i <= len; i++)
5041 end[i] = dtrace_load8((uintptr_t)s++);
5042 }
5043
5044 /*
5045 * Now for the node name...
5046 */
5047 s = (char *)dtrace_loadptr(daddr +
5048 offsetof(struct dev_info, devi_node_name));
5049
5050 daddr = dtrace_loadptr(daddr +
5051 offsetof(struct dev_info, devi_parent));
5052
5053 /*
5054 * If our parent is NULL (that is, if we're the root
5055 * node), we're going to use the special path
5056 * "devices".
5057 */
5058 if (daddr == 0)
5059 s = "devices";
5060
5061 len = dtrace_strlen(s, size);
5062 if (*flags & CPU_DTRACE_FAULT)
5063 break;
5064
5065 if ((end -= (len + 1)) < start)
5066 break;
5067
5068 for (i = 1; i <= len; i++)
5069 end[i] = dtrace_load8((uintptr_t)s++);
5070 *end = '/';
5071
5072 if (depth++ > dtrace_devdepth_max) {
5073 *flags |= CPU_DTRACE_ILLOP;
5074 break;
5075 }
5076 }
5077
5078 if (end < start)
5079 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5080
5081 if (daddr == 0) {
5082 regs[rd] = (uintptr_t)end;
5083 mstate->dtms_scratch_ptr += size;
5084 }
5085
5086 break;
5087 }
5088
5089 case DIF_SUBR_STRJOIN: {
5090 char *d = (char *)mstate->dtms_scratch_ptr;
5091 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5092 uintptr_t s1 = tupregs[0].dttk_value;
5093 uintptr_t s2 = tupregs[1].dttk_value;
5094 int i = 0, j = 0;
5095 size_t lim1, lim2;
5096 char c;
5097
5098 if (!dtrace_strcanload(s1, size, &lim1, mstate, vstate) ||
5099 !dtrace_strcanload(s2, size, &lim2, mstate, vstate)) {
5100 regs[rd] = 0;
5101 break;
5102 }
5103
5104 if (!DTRACE_INSCRATCH(mstate, size)) {
5105 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5106 regs[rd] = 0;
5107 break;
5108 }
5109
5110 for (;;) {
5111 if (i >= size) {
5112 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5113 regs[rd] = 0;
5114 break;
5115 }
5116 c = (i >= lim1) ? '\0' : dtrace_load8(s1++);
5117 if ((d[i++] = c) == '\0') {
5118 i--;
5119 break;
5120 }
5121 }
5122
5123 for (;;) {
5124 if (i >= size) {
5125 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5126 regs[rd] = 0;
5127 break;
5128 }
5129
5130 c = (j++ >= lim2) ? '\0' : dtrace_load8(s2++);
5131 if ((d[i++] = c) == '\0')
5132 break;
5133 }
5134
5135 if (i < size) {
5136 mstate->dtms_scratch_ptr += i;
5137 regs[rd] = (uintptr_t)d;
5138 }
5139
5140 break;
5141 }
5142
5143 case DIF_SUBR_STRTOLL: {
5144 uintptr_t s = tupregs[0].dttk_value;
5145 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5146 size_t lim;
5147 int base = 10;
5148
5149 if (nargs > 1) {
5150 if ((base = tupregs[1].dttk_value) <= 1 ||
5151 base > ('z' - 'a' + 1) + ('9' - '0' + 1)) {
5152 *flags |= CPU_DTRACE_ILLOP;
5153 break;
5154 }
5155 }
5156
5157 if (!dtrace_strcanload(s, size, &lim, mstate, vstate)) {
5158 regs[rd] = INT64_MIN;
5159 break;
5160 }
5161
5162 regs[rd] = dtrace_strtoll((char *)s, base, lim);
5163 break;
5164 }
5165
5166 case DIF_SUBR_LLTOSTR: {
5167 int64_t i = (int64_t)tupregs[0].dttk_value;
5168 uint64_t val, digit;
5169 uint64_t size = 65; /* enough room for 2^64 in binary */
5170 char *end = (char *)mstate->dtms_scratch_ptr + size - 1;
5171 int base = 10;
5172
5173 if (nargs > 1) {
5174 if ((base = tupregs[1].dttk_value) <= 1 ||
5175 base > ('z' - 'a' + 1) + ('9' - '0' + 1)) {
5176 *flags |= CPU_DTRACE_ILLOP;
5177 break;
5178 }
5179 }
5180
5181 val = (base == 10 && i < 0) ? i * -1 : i;
5182
5183 if (!DTRACE_INSCRATCH(mstate, size)) {
5184 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5185 regs[rd] = 0;
5186 break;
5187 }
5188
5189 for (*end-- = '\0'; val; val /= base) {
5190 if ((digit = val % base) <= '9' - '0') {
5191 *end-- = '0' + digit;
5192 } else {
5193 *end-- = 'a' + (digit - ('9' - '0') - 1);
5194 }
5195 }
5196
5197 if (i == 0 && base == 16)
5198 *end-- = '0';
5199
5200 if (base == 16)
5201 *end-- = 'x';
5202
5203 if (i == 0 || base == 8 || base == 16)
5204 *end-- = '0';
5205
5206 if (i < 0 && base == 10)
5207 *end-- = '-';
5208
5209 regs[rd] = (uintptr_t)end + 1;
5210 mstate->dtms_scratch_ptr += size;
5211 break;
5212 }
5213
5214 case DIF_SUBR_HTONS:
5215 case DIF_SUBR_NTOHS:
5216 #ifdef _BIG_ENDIAN
5217 regs[rd] = (uint16_t)tupregs[0].dttk_value;
5218 #else
5219 regs[rd] = DT_BSWAP_16((uint16_t)tupregs[0].dttk_value);
5220 #endif
5221 break;
5222
5223
5224 case DIF_SUBR_HTONL:
5225 case DIF_SUBR_NTOHL:
5226 #ifdef _BIG_ENDIAN
5227 regs[rd] = (uint32_t)tupregs[0].dttk_value;
5228 #else
5229 regs[rd] = DT_BSWAP_32((uint32_t)tupregs[0].dttk_value);
5230 #endif
5231 break;
5232
5233
5234 case DIF_SUBR_HTONLL:
5235 case DIF_SUBR_NTOHLL:
5236 #ifdef _BIG_ENDIAN
5237 regs[rd] = (uint64_t)tupregs[0].dttk_value;
5238 #else
5239 regs[rd] = DT_BSWAP_64((uint64_t)tupregs[0].dttk_value);
5240 #endif
5241 break;
5242
5243
5244 case DIF_SUBR_DIRNAME:
5245 case DIF_SUBR_BASENAME: {
5246 char *dest = (char *)mstate->dtms_scratch_ptr;
5247 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5248 uintptr_t src = tupregs[0].dttk_value;
5249 int i, j, len = dtrace_strlen((char *)src, size);
5250 int lastbase = -1, firstbase = -1, lastdir = -1;
5251 int start, end;
5252
5253 if (!dtrace_canload(src, len + 1, mstate, vstate)) {
5254 regs[rd] = 0;
5255 break;
5256 }
5257
5258 if (!DTRACE_INSCRATCH(mstate, size)) {
5259 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5260 regs[rd] = 0;
5261 break;
5262 }
5263
5264 /*
5265 * The basename and dirname for a zero-length string is
5266 * defined to be "."
5267 */
5268 if (len == 0) {
5269 len = 1;
5270 src = (uintptr_t)".";
5271 }
5272
5273 /*
5274 * Start from the back of the string, moving back toward the
5275 * front until we see a character that isn't a slash. That
5276 * character is the last character in the basename.
5277 */
5278 for (i = len - 1; i >= 0; i--) {
5279 if (dtrace_load8(src + i) != '/')
5280 break;
5281 }
5282
5283 if (i >= 0)
5284 lastbase = i;
5285
5286 /*
5287 * Starting from the last character in the basename, move
5288 * towards the front until we find a slash. The character
5289 * that we processed immediately before that is the first
5290 * character in the basename.
5291 */
5292 for (; i >= 0; i--) {
5293 if (dtrace_load8(src + i) == '/')
5294 break;
5295 }
5296
5297 if (i >= 0)
5298 firstbase = i + 1;
5299
5300 /*
5301 * Now keep going until we find a non-slash character. That
5302 * character is the last character in the dirname.
5303 */
5304 for (; i >= 0; i--) {
5305 if (dtrace_load8(src + i) != '/')
5306 break;
5307 }
5308
5309 if (i >= 0)
5310 lastdir = i;
5311
5312 ASSERT(!(lastbase == -1 && firstbase != -1));
5313 ASSERT(!(firstbase == -1 && lastdir != -1));
5314
5315 if (lastbase == -1) {
5316 /*
5317 * We didn't find a non-slash character. We know that
5318 * the length is non-zero, so the whole string must be
5319 * slashes. In either the dirname or the basename
5320 * case, we return '/'.
5321 */
5322 ASSERT(firstbase == -1);
5323 firstbase = lastbase = lastdir = 0;
5324 }
5325
5326 if (firstbase == -1) {
5327 /*
5328 * The entire string consists only of a basename
5329 * component. If we're looking for dirname, we need
5330 * to change our string to be just "."; if we're
5331 * looking for a basename, we'll just set the first
5332 * character of the basename to be 0.
5333 */
5334 if (subr == DIF_SUBR_DIRNAME) {
5335 ASSERT(lastdir == -1);
5336 src = (uintptr_t)".";
5337 lastdir = 0;
5338 } else {
5339 firstbase = 0;
5340 }
5341 }
5342
5343 if (subr == DIF_SUBR_DIRNAME) {
5344 if (lastdir == -1) {
5345 /*
5346 * We know that we have a slash in the name --
5347 * or lastdir would be set to 0, above. And
5348 * because lastdir is -1, we know that this
5349 * slash must be the first character. (That
5350 * is, the full string must be of the form
5351 * "/basename".) In this case, the last
5352 * character of the directory name is 0.
5353 */
5354 lastdir = 0;
5355 }
5356
5357 start = 0;
5358 end = lastdir;
5359 } else {
5360 ASSERT(subr == DIF_SUBR_BASENAME);
5361 ASSERT(firstbase != -1 && lastbase != -1);
5362 start = firstbase;
5363 end = lastbase;
5364 }
5365
5366 for (i = start, j = 0; i <= end && j < size - 1; i++, j++)
5367 dest[j] = dtrace_load8(src + i);
5368
5369 dest[j] = '\0';
5370 regs[rd] = (uintptr_t)dest;
5371 mstate->dtms_scratch_ptr += size;
5372 break;
5373 }
5374
5375 case DIF_SUBR_GETF: {
5376 uintptr_t fd = tupregs[0].dttk_value;
5377 uf_info_t *finfo = &curthread->t_procp->p_user.u_finfo;
5378 file_t *fp;
5379
5380 if (!dtrace_priv_proc(state, mstate)) {
5381 regs[rd] = 0;
5382 break;
5383 }
5384
5385 /*
5386 * This is safe because fi_nfiles only increases, and the
5387 * fi_list array is not freed when the array size doubles.
5388 * (See the comment in flist_grow() for details on the
5389 * management of the u_finfo structure.)
5390 */
5391 fp = fd < finfo->fi_nfiles ? finfo->fi_list[fd].uf_file : NULL;
5392
5393 mstate->dtms_getf = fp;
5394 regs[rd] = (uintptr_t)fp;
5395 break;
5396 }
5397
5398 case DIF_SUBR_CLEANPATH: {
5399 char *dest = (char *)mstate->dtms_scratch_ptr, c;
5400 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5401 uintptr_t src = tupregs[0].dttk_value;
5402 size_t lim;
5403 int i = 0, j = 0;
5404 zone_t *z;
5405
5406 if (!dtrace_strcanload(src, size, &lim, mstate, vstate)) {
5407 regs[rd] = 0;
5408 break;
5409 }
5410
5411 if (!DTRACE_INSCRATCH(mstate, size)) {
5412 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5413 regs[rd] = 0;
5414 break;
5415 }
5416
5417 /*
5418 * Move forward, loading each character.
5419 */
5420 do {
5421 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5422 next:
5423 if (j + 5 >= size) /* 5 = strlen("/..c\0") */
5424 break;
5425
5426 if (c != '/') {
5427 dest[j++] = c;
5428 continue;
5429 }
5430
5431 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5432
5433 if (c == '/') {
5434 /*
5435 * We have two slashes -- we can just advance
5436 * to the next character.
5437 */
5438 goto next;
5439 }
5440
5441 if (c != '.') {
5442 /*
5443 * This is not "." and it's not ".." -- we can
5444 * just store the "/" and this character and
5445 * drive on.
5446 */
5447 dest[j++] = '/';
5448 dest[j++] = c;
5449 continue;
5450 }
5451
5452 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5453
5454 if (c == '/') {
5455 /*
5456 * This is a "/./" component. We're not going
5457 * to store anything in the destination buffer;
5458 * we're just going to go to the next component.
5459 */
5460 goto next;
5461 }
5462
5463 if (c != '.') {
5464 /*
5465 * This is not ".." -- we can just store the
5466 * "/." and this character and continue
5467 * processing.
5468 */
5469 dest[j++] = '/';
5470 dest[j++] = '.';
5471 dest[j++] = c;
5472 continue;
5473 }
5474
5475 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5476
5477 if (c != '/' && c != '\0') {
5478 /*
5479 * This is not ".." -- it's "..[mumble]".
5480 * We'll store the "/.." and this character
5481 * and continue processing.
5482 */
5483 dest[j++] = '/';
5484 dest[j++] = '.';
5485 dest[j++] = '.';
5486 dest[j++] = c;
5487 continue;
5488 }
5489
5490 /*
5491 * This is "/../" or "/..\0". We need to back up
5492 * our destination pointer until we find a "/".
5493 */
5494 i--;
5495 while (j != 0 && dest[--j] != '/')
5496 continue;
5497
5498 if (c == '\0')
5499 dest[++j] = '/';
5500 } while (c != '\0');
5501
5502 dest[j] = '\0';
5503
5504 if (mstate->dtms_getf != NULL &&
5505 !(mstate->dtms_access & DTRACE_ACCESS_KERNEL) &&
5506 (z = state->dts_cred.dcr_cred->cr_zone) != kcred->cr_zone) {
5507 /*
5508 * If we've done a getf() as a part of this ECB and we
5509 * don't have kernel access (and we're not in the global
5510 * zone), check if the path we cleaned up begins with
5511 * the zone's root path, and trim it off if so. Note
5512 * that this is an output cleanliness issue, not a
5513 * security issue: knowing one's zone root path does
5514 * not enable privilege escalation.
5515 */
5516 if (strstr(dest, z->zone_rootpath) == dest)
5517 dest += strlen(z->zone_rootpath) - 1;
5518 }
5519
5520 regs[rd] = (uintptr_t)dest;
5521 mstate->dtms_scratch_ptr += size;
5522 break;
5523 }
5524
5525 case DIF_SUBR_INET_NTOA:
5526 case DIF_SUBR_INET_NTOA6:
5527 case DIF_SUBR_INET_NTOP: {
5528 size_t size;
5529 int af, argi, i;
5530 char *base, *end;
5531
5532 if (subr == DIF_SUBR_INET_NTOP) {
5533 af = (int)tupregs[0].dttk_value;
5534 argi = 1;
5535 } else {
5536 af = subr == DIF_SUBR_INET_NTOA ? AF_INET: AF_INET6;
5537 argi = 0;
5538 }
5539
5540 if (af == AF_INET) {
5541 ipaddr_t ip4;
5542 uint8_t *ptr8, val;
5543
5544 if (!dtrace_canload(tupregs[argi].dttk_value,
5545 sizeof (ipaddr_t), mstate, vstate)) {
5546 regs[rd] = 0;
5547 break;
5548 }
5549
5550 /*
5551 * Safely load the IPv4 address.
5552 */
5553 ip4 = dtrace_load32(tupregs[argi].dttk_value);
5554
5555 /*
5556 * Check an IPv4 string will fit in scratch.
5557 */
5558 size = INET_ADDRSTRLEN;
5559 if (!DTRACE_INSCRATCH(mstate, size)) {
5560 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5561 regs[rd] = 0;
5562 break;
5563 }
5564 base = (char *)mstate->dtms_scratch_ptr;
5565 end = (char *)mstate->dtms_scratch_ptr + size - 1;
5566
5567 /*
5568 * Stringify as a dotted decimal quad.
5569 */
5570 *end-- = '\0';
5571 ptr8 = (uint8_t *)&ip4;
5572 for (i = 3; i >= 0; i--) {
5573 val = ptr8[i];
5574
5575 if (val == 0) {
5576 *end-- = '0';
5577 } else {
5578 for (; val; val /= 10) {
5579 *end-- = '0' + (val % 10);
5580 }
5581 }
5582
5583 if (i > 0)
5584 *end-- = '.';
5585 }
5586 ASSERT(end + 1 >= base);
5587
5588 } else if (af == AF_INET6) {
5589 struct in6_addr ip6;
5590 int firstzero, tryzero, numzero, v6end;
5591 uint16_t val;
5592 const char digits[] = "0123456789abcdef";
5593
5594 /*
5595 * Stringify using RFC 1884 convention 2 - 16 bit
5596 * hexadecimal values with a zero-run compression.
5597 * Lower case hexadecimal digits are used.
5598 * eg, fe80::214:4fff:fe0b:76c8.
5599 * The IPv4 embedded form is returned for inet_ntop,
5600 * just the IPv4 string is returned for inet_ntoa6.
5601 */
5602
5603 if (!dtrace_canload(tupregs[argi].dttk_value,
5604 sizeof (struct in6_addr), mstate, vstate)) {
5605 regs[rd] = 0;
5606 break;
5607 }
5608
5609 /*
5610 * Safely load the IPv6 address.
5611 */
5612 dtrace_bcopy(
5613 (void *)(uintptr_t)tupregs[argi].dttk_value,
5614 (void *)(uintptr_t)&ip6, sizeof (struct in6_addr));
5615
5616 /*
5617 * Check an IPv6 string will fit in scratch.
5618 */
5619 size = INET6_ADDRSTRLEN;
5620 if (!DTRACE_INSCRATCH(mstate, size)) {
5621 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5622 regs[rd] = 0;
5623 break;
5624 }
5625 base = (char *)mstate->dtms_scratch_ptr;
5626 end = (char *)mstate->dtms_scratch_ptr + size - 1;
5627 *end-- = '\0';
5628
5629 /*
5630 * Find the longest run of 16 bit zero values
5631 * for the single allowed zero compression - "::".
5632 */
5633 firstzero = -1;
5634 tryzero = -1;
5635 numzero = 1;
5636 for (i = 0; i < sizeof (struct in6_addr); i++) {
5637 if (ip6._S6_un._S6_u8[i] == 0 &&
5638 tryzero == -1 && i % 2 == 0) {
5639 tryzero = i;
5640 continue;
5641 }
5642
5643 if (tryzero != -1 &&
5644 (ip6._S6_un._S6_u8[i] != 0 ||
5645 i == sizeof (struct in6_addr) - 1)) {
5646
5647 if (i - tryzero <= numzero) {
5648 tryzero = -1;
5649 continue;
5650 }
5651
5652 firstzero = tryzero;
5653 numzero = i - i % 2 - tryzero;
5654 tryzero = -1;
5655
5656 if (ip6._S6_un._S6_u8[i] == 0 &&
5657 i == sizeof (struct in6_addr) - 1)
5658 numzero += 2;
5659 }
5660 }
5661 ASSERT(firstzero + numzero <= sizeof (struct in6_addr));
5662
5663 /*
5664 * Check for an IPv4 embedded address.
5665 */
5666 v6end = sizeof (struct in6_addr) - 2;
5667 if (IN6_IS_ADDR_V4MAPPED(&ip6) ||
5668 IN6_IS_ADDR_V4COMPAT(&ip6)) {
5669 for (i = sizeof (struct in6_addr) - 1;
5670 i >= DTRACE_V4MAPPED_OFFSET; i--) {
5671 ASSERT(end >= base);
5672
5673 val = ip6._S6_un._S6_u8[i];
5674
5675 if (val == 0) {
5676 *end-- = '0';
5677 } else {
5678 for (; val; val /= 10) {
5679 *end-- = '0' + val % 10;
5680 }
5681 }
5682
5683 if (i > DTRACE_V4MAPPED_OFFSET)
5684 *end-- = '.';
5685 }
5686
5687 if (subr == DIF_SUBR_INET_NTOA6)
5688 goto inetout;
5689
5690 /*
5691 * Set v6end to skip the IPv4 address that
5692 * we have already stringified.
5693 */
5694 v6end = 10;
5695 }
5696
5697 /*
5698 * Build the IPv6 string by working through the
5699 * address in reverse.
5700 */
5701 for (i = v6end; i >= 0; i -= 2) {
5702 ASSERT(end >= base);
5703
5704 if (i == firstzero + numzero - 2) {
5705 *end-- = ':';
5706 *end-- = ':';
5707 i -= numzero - 2;
5708 continue;
5709 }
5710
5711 if (i < 14 && i != firstzero - 2)
5712 *end-- = ':';
5713
5714 val = (ip6._S6_un._S6_u8[i] << 8) +
5715 ip6._S6_un._S6_u8[i + 1];
5716
5717 if (val == 0) {
5718 *end-- = '0';
5719 } else {
5720 for (; val; val /= 16) {
5721 *end-- = digits[val % 16];
5722 }
5723 }
5724 }
5725 ASSERT(end + 1 >= base);
5726
5727 } else {
5728 /*
5729 * The user didn't use AH_INET or AH_INET6.
5730 */
5731 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
5732 regs[rd] = 0;
5733 break;
5734 }
5735
5736 inetout: regs[rd] = (uintptr_t)end + 1;
5737 mstate->dtms_scratch_ptr += size;
5738 break;
5739 }
5740
5741 }
5742 }
5743
5744 /*
5745 * Emulate the execution of DTrace IR instructions specified by the given
5746 * DIF object. This function is deliberately void of assertions as all of
5747 * the necessary checks are handled by a call to dtrace_difo_validate().
5748 */
5749 static uint64_t
5750 dtrace_dif_emulate(dtrace_difo_t *difo, dtrace_mstate_t *mstate,
5751 dtrace_vstate_t *vstate, dtrace_state_t *state)
5752 {
5753 const dif_instr_t *text = difo->dtdo_buf;
5754 const uint_t textlen = difo->dtdo_len;
5755 const char *strtab = difo->dtdo_strtab;
5756 const uint64_t *inttab = difo->dtdo_inttab;
5757
5758 uint64_t rval = 0;
5759 dtrace_statvar_t *svar;
5760 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
5761 dtrace_difv_t *v;
5762 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
5763 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
5764
5765 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
5766 uint64_t regs[DIF_DIR_NREGS];
5767 uint64_t *tmp;
5768
5769 uint8_t cc_n = 0, cc_z = 0, cc_v = 0, cc_c = 0;
5770 int64_t cc_r;
5771 uint_t pc = 0, id, opc;
5772 uint8_t ttop = 0;
5773 dif_instr_t instr;
5774 uint_t r1, r2, rd;
5775
5776 /*
5777 * We stash the current DIF object into the machine state: we need it
5778 * for subsequent access checking.
5779 */
5780 mstate->dtms_difo = difo;
5781
5782 regs[DIF_REG_R0] = 0; /* %r0 is fixed at zero */
5783
5784 while (pc < textlen && !(*flags & CPU_DTRACE_FAULT)) {
5785 opc = pc;
5786
5787 instr = text[pc++];
5788 r1 = DIF_INSTR_R1(instr);
5789 r2 = DIF_INSTR_R2(instr);
5790 rd = DIF_INSTR_RD(instr);
5791
5792 switch (DIF_INSTR_OP(instr)) {
5793 case DIF_OP_OR:
5794 regs[rd] = regs[r1] | regs[r2];
5795 break;
5796 case DIF_OP_XOR:
5797 regs[rd] = regs[r1] ^ regs[r2];
5798 break;
5799 case DIF_OP_AND:
5800 regs[rd] = regs[r1] & regs[r2];
5801 break;
5802 case DIF_OP_SLL:
5803 regs[rd] = regs[r1] << regs[r2];
5804 break;
5805 case DIF_OP_SRL:
5806 regs[rd] = regs[r1] >> regs[r2];
5807 break;
5808 case DIF_OP_SUB:
5809 regs[rd] = regs[r1] - regs[r2];
5810 break;
5811 case DIF_OP_ADD:
5812 regs[rd] = regs[r1] + regs[r2];
5813 break;
5814 case DIF_OP_MUL:
5815 regs[rd] = regs[r1] * regs[r2];
5816 break;
5817 case DIF_OP_SDIV:
5818 if (regs[r2] == 0) {
5819 regs[rd] = 0;
5820 *flags |= CPU_DTRACE_DIVZERO;
5821 } else {
5822 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5823 regs[rd] = (int64_t)regs[r1] /
5824 (int64_t)regs[r2];
5825 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5826 }
5827 break;
5828
5829 case DIF_OP_UDIV:
5830 if (regs[r2] == 0) {
5831 regs[rd] = 0;
5832 *flags |= CPU_DTRACE_DIVZERO;
5833 } else {
5834 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5835 regs[rd] = regs[r1] / regs[r2];
5836 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5837 }
5838 break;
5839
5840 case DIF_OP_SREM:
5841 if (regs[r2] == 0) {
5842 regs[rd] = 0;
5843 *flags |= CPU_DTRACE_DIVZERO;
5844 } else {
5845 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5846 regs[rd] = (int64_t)regs[r1] %
5847 (int64_t)regs[r2];
5848 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5849 }
5850 break;
5851
5852 case DIF_OP_UREM:
5853 if (regs[r2] == 0) {
5854 regs[rd] = 0;
5855 *flags |= CPU_DTRACE_DIVZERO;
5856 } else {
5857 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5858 regs[rd] = regs[r1] % regs[r2];
5859 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5860 }
5861 break;
5862
5863 case DIF_OP_NOT:
5864 regs[rd] = ~regs[r1];
5865 break;
5866 case DIF_OP_MOV:
5867 regs[rd] = regs[r1];
5868 break;
5869 case DIF_OP_CMP:
5870 cc_r = regs[r1] - regs[r2];
5871 cc_n = cc_r < 0;
5872 cc_z = cc_r == 0;
5873 cc_v = 0;
5874 cc_c = regs[r1] < regs[r2];
5875 break;
5876 case DIF_OP_TST:
5877 cc_n = cc_v = cc_c = 0;
5878 cc_z = regs[r1] == 0;
5879 break;
5880 case DIF_OP_BA:
5881 pc = DIF_INSTR_LABEL(instr);
5882 break;
5883 case DIF_OP_BE:
5884 if (cc_z)
5885 pc = DIF_INSTR_LABEL(instr);
5886 break;
5887 case DIF_OP_BNE:
5888 if (cc_z == 0)
5889 pc = DIF_INSTR_LABEL(instr);
5890 break;
5891 case DIF_OP_BG:
5892 if ((cc_z | (cc_n ^ cc_v)) == 0)
5893 pc = DIF_INSTR_LABEL(instr);
5894 break;
5895 case DIF_OP_BGU:
5896 if ((cc_c | cc_z) == 0)
5897 pc = DIF_INSTR_LABEL(instr);
5898 break;
5899 case DIF_OP_BGE:
5900 if ((cc_n ^ cc_v) == 0)
5901 pc = DIF_INSTR_LABEL(instr);
5902 break;
5903 case DIF_OP_BGEU:
5904 if (cc_c == 0)
5905 pc = DIF_INSTR_LABEL(instr);
5906 break;
5907 case DIF_OP_BL:
5908 if (cc_n ^ cc_v)
5909 pc = DIF_INSTR_LABEL(instr);
5910 break;
5911 case DIF_OP_BLU:
5912 if (cc_c)
5913 pc = DIF_INSTR_LABEL(instr);
5914 break;
5915 case DIF_OP_BLE:
5916 if (cc_z | (cc_n ^ cc_v))
5917 pc = DIF_INSTR_LABEL(instr);
5918 break;
5919 case DIF_OP_BLEU:
5920 if (cc_c | cc_z)
5921 pc = DIF_INSTR_LABEL(instr);
5922 break;
5923 case DIF_OP_RLDSB:
5924 if (!dtrace_canload(regs[r1], 1, mstate, vstate))
5925 break;
5926 /*FALLTHROUGH*/
5927 case DIF_OP_LDSB:
5928 regs[rd] = (int8_t)dtrace_load8(regs[r1]);
5929 break;
5930 case DIF_OP_RLDSH:
5931 if (!dtrace_canload(regs[r1], 2, mstate, vstate))
5932 break;
5933 /*FALLTHROUGH*/
5934 case DIF_OP_LDSH:
5935 regs[rd] = (int16_t)dtrace_load16(regs[r1]);
5936 break;
5937 case DIF_OP_RLDSW:
5938 if (!dtrace_canload(regs[r1], 4, mstate, vstate))
5939 break;
5940 /*FALLTHROUGH*/
5941 case DIF_OP_LDSW:
5942 regs[rd] = (int32_t)dtrace_load32(regs[r1]);
5943 break;
5944 case DIF_OP_RLDUB:
5945 if (!dtrace_canload(regs[r1], 1, mstate, vstate))
5946 break;
5947 /*FALLTHROUGH*/
5948 case DIF_OP_LDUB:
5949 regs[rd] = dtrace_load8(regs[r1]);
5950 break;
5951 case DIF_OP_RLDUH:
5952 if (!dtrace_canload(regs[r1], 2, mstate, vstate))
5953 break;
5954 /*FALLTHROUGH*/
5955 case DIF_OP_LDUH:
5956 regs[rd] = dtrace_load16(regs[r1]);
5957 break;
5958 case DIF_OP_RLDUW:
5959 if (!dtrace_canload(regs[r1], 4, mstate, vstate))
5960 break;
5961 /*FALLTHROUGH*/
5962 case DIF_OP_LDUW:
5963 regs[rd] = dtrace_load32(regs[r1]);
5964 break;
5965 case DIF_OP_RLDX:
5966 if (!dtrace_canload(regs[r1], 8, mstate, vstate))
5967 break;
5968 /*FALLTHROUGH*/
5969 case DIF_OP_LDX:
5970 regs[rd] = dtrace_load64(regs[r1]);
5971 break;
5972 case DIF_OP_ULDSB:
5973 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5974 regs[rd] = (int8_t)
5975 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
5976 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5977 break;
5978 case DIF_OP_ULDSH:
5979 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5980 regs[rd] = (int16_t)
5981 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
5982 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5983 break;
5984 case DIF_OP_ULDSW:
5985 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5986 regs[rd] = (int32_t)
5987 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
5988 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5989 break;
5990 case DIF_OP_ULDUB:
5991 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5992 regs[rd] =
5993 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
5994 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5995 break;
5996 case DIF_OP_ULDUH:
5997 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5998 regs[rd] =
5999 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
6000 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6001 break;
6002 case DIF_OP_ULDUW:
6003 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6004 regs[rd] =
6005 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
6006 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6007 break;
6008 case DIF_OP_ULDX:
6009 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6010 regs[rd] =
6011 dtrace_fuword64((void *)(uintptr_t)regs[r1]);
6012 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6013 break;
6014 case DIF_OP_RET:
6015 rval = regs[rd];
6016 pc = textlen;
6017 break;
6018 case DIF_OP_NOP:
6019 break;
6020 case DIF_OP_SETX:
6021 regs[rd] = inttab[DIF_INSTR_INTEGER(instr)];
6022 break;
6023 case DIF_OP_SETS:
6024 regs[rd] = (uint64_t)(uintptr_t)
6025 (strtab + DIF_INSTR_STRING(instr));
6026 break;
6027 case DIF_OP_SCMP: {
6028 size_t sz = state->dts_options[DTRACEOPT_STRSIZE];
6029 uintptr_t s1 = regs[r1];
6030 uintptr_t s2 = regs[r2];
6031 size_t lim1, lim2;
6032
6033 if (s1 != 0 &&
6034 !dtrace_strcanload(s1, sz, &lim1, mstate, vstate))
6035 break;
6036 if (s2 != 0 &&
6037 !dtrace_strcanload(s2, sz, &lim2, mstate, vstate))
6038 break;
6039
6040 cc_r = dtrace_strncmp((char *)s1, (char *)s2,
6041 MIN(lim1, lim2));
6042
6043 cc_n = cc_r < 0;
6044 cc_z = cc_r == 0;
6045 cc_v = cc_c = 0;
6046 break;
6047 }
6048 case DIF_OP_LDGA:
6049 regs[rd] = dtrace_dif_variable(mstate, state,
6050 r1, regs[r2]);
6051 break;
6052 case DIF_OP_LDGS:
6053 id = DIF_INSTR_VAR(instr);
6054
6055 if (id >= DIF_VAR_OTHER_UBASE) {
6056 uintptr_t a;
6057
6058 id -= DIF_VAR_OTHER_UBASE;
6059 svar = vstate->dtvs_globals[id];
6060 ASSERT(svar != NULL);
6061 v = &svar->dtsv_var;
6062
6063 if (!(v->dtdv_type.dtdt_flags & DIF_TF_BYREF)) {
6064 regs[rd] = svar->dtsv_data;
6065 break;
6066 }
6067
6068 a = (uintptr_t)svar->dtsv_data;
6069
6070 if (*(uint8_t *)a == UINT8_MAX) {
6071 /*
6072 * If the 0th byte is set to UINT8_MAX
6073 * then this is to be treated as a
6074 * reference to a NULL variable.
6075 */
6076 regs[rd] = 0;
6077 } else {
6078 regs[rd] = a + sizeof (uint64_t);
6079 }
6080
6081 break;
6082 }
6083
6084 regs[rd] = dtrace_dif_variable(mstate, state, id, 0);
6085 break;
6086
6087 case DIF_OP_STGA:
6088 dtrace_dif_variable_write(mstate, state, r1, regs[r2],
6089 regs[rd]);
6090 break;
6091
6092 case DIF_OP_STGS:
6093 id = DIF_INSTR_VAR(instr);
6094
6095 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6096 id -= DIF_VAR_OTHER_UBASE;
6097
6098 VERIFY(id < vstate->dtvs_nglobals);
6099 svar = vstate->dtvs_globals[id];
6100 ASSERT(svar != NULL);
6101 v = &svar->dtsv_var;
6102
6103 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6104 uintptr_t a = (uintptr_t)svar->dtsv_data;
6105 size_t lim;
6106
6107 ASSERT(a != (uintptr_t)NULL);
6108 ASSERT(svar->dtsv_size != 0);
6109
6110 if (regs[rd] == 0) {
6111 *(uint8_t *)a = UINT8_MAX;
6112 break;
6113 } else {
6114 *(uint8_t *)a = 0;
6115 a += sizeof (uint64_t);
6116 }
6117 if (!dtrace_vcanload(
6118 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
6119 &lim, mstate, vstate))
6120 break;
6121
6122 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6123 (void *)a, &v->dtdv_type, lim);
6124 break;
6125 }
6126
6127 svar->dtsv_data = regs[rd];
6128 break;
6129
6130 case DIF_OP_LDTA:
6131 /*
6132 * There are no DTrace built-in thread-local arrays at
6133 * present. This opcode is saved for future work.
6134 */
6135 *flags |= CPU_DTRACE_ILLOP;
6136 regs[rd] = 0;
6137 break;
6138
6139 case DIF_OP_LDLS:
6140 id = DIF_INSTR_VAR(instr);
6141
6142 if (id < DIF_VAR_OTHER_UBASE) {
6143 /*
6144 * For now, this has no meaning.
6145 */
6146 regs[rd] = 0;
6147 break;
6148 }
6149
6150 id -= DIF_VAR_OTHER_UBASE;
6151
6152 ASSERT(id < vstate->dtvs_nlocals);
6153 ASSERT(vstate->dtvs_locals != NULL);
6154
6155 svar = vstate->dtvs_locals[id];
6156 ASSERT(svar != NULL);
6157 v = &svar->dtsv_var;
6158
6159 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6160 uintptr_t a = (uintptr_t)svar->dtsv_data;
6161 size_t sz = v->dtdv_type.dtdt_size;
6162
6163 sz += sizeof (uint64_t);
6164 ASSERT(svar->dtsv_size == NCPU * sz);
6165 a += CPU->cpu_id * sz;
6166
6167 if (*(uint8_t *)a == UINT8_MAX) {
6168 /*
6169 * If the 0th byte is set to UINT8_MAX
6170 * then this is to be treated as a
6171 * reference to a NULL variable.
6172 */
6173 regs[rd] = 0;
6174 } else {
6175 regs[rd] = a + sizeof (uint64_t);
6176 }
6177
6178 break;
6179 }
6180
6181 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
6182 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
6183 regs[rd] = tmp[CPU->cpu_id];
6184 break;
6185
6186 case DIF_OP_STLS:
6187 id = DIF_INSTR_VAR(instr);
6188
6189 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6190 id -= DIF_VAR_OTHER_UBASE;
6191 VERIFY(id < vstate->dtvs_nlocals);
6192
6193 ASSERT(vstate->dtvs_locals != NULL);
6194 svar = vstate->dtvs_locals[id];
6195 ASSERT(svar != NULL);
6196 v = &svar->dtsv_var;
6197
6198 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6199 uintptr_t a = (uintptr_t)svar->dtsv_data;
6200 size_t sz = v->dtdv_type.dtdt_size;
6201 size_t lim;
6202
6203 sz += sizeof (uint64_t);
6204 ASSERT(svar->dtsv_size == NCPU * sz);
6205 a += CPU->cpu_id * sz;
6206
6207 if (regs[rd] == 0) {
6208 *(uint8_t *)a = UINT8_MAX;
6209 break;
6210 } else {
6211 *(uint8_t *)a = 0;
6212 a += sizeof (uint64_t);
6213 }
6214
6215 if (!dtrace_vcanload(
6216 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
6217 &lim, mstate, vstate))
6218 break;
6219
6220 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6221 (void *)a, &v->dtdv_type, lim);
6222 break;
6223 }
6224
6225 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
6226 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
6227 tmp[CPU->cpu_id] = regs[rd];
6228 break;
6229
6230 case DIF_OP_LDTS: {
6231 dtrace_dynvar_t *dvar;
6232 dtrace_key_t *key;
6233
6234 id = DIF_INSTR_VAR(instr);
6235 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6236 id -= DIF_VAR_OTHER_UBASE;
6237 v = &vstate->dtvs_tlocals[id];
6238
6239 key = &tupregs[DIF_DTR_NREGS];
6240 key[0].dttk_value = (uint64_t)id;
6241 key[0].dttk_size = 0;
6242 DTRACE_TLS_THRKEY(key[1].dttk_value);
6243 key[1].dttk_size = 0;
6244
6245 dvar = dtrace_dynvar(dstate, 2, key,
6246 sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC,
6247 mstate, vstate);
6248
6249 if (dvar == NULL) {
6250 regs[rd] = 0;
6251 break;
6252 }
6253
6254 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6255 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
6256 } else {
6257 regs[rd] = *((uint64_t *)dvar->dtdv_data);
6258 }
6259
6260 break;
6261 }
6262
6263 case DIF_OP_STTS: {
6264 dtrace_dynvar_t *dvar;
6265 dtrace_key_t *key;
6266
6267 id = DIF_INSTR_VAR(instr);
6268 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6269 id -= DIF_VAR_OTHER_UBASE;
6270 VERIFY(id < vstate->dtvs_ntlocals);
6271
6272 key = &tupregs[DIF_DTR_NREGS];
6273 key[0].dttk_value = (uint64_t)id;
6274 key[0].dttk_size = 0;
6275 DTRACE_TLS_THRKEY(key[1].dttk_value);
6276 key[1].dttk_size = 0;
6277 v = &vstate->dtvs_tlocals[id];
6278
6279 dvar = dtrace_dynvar(dstate, 2, key,
6280 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
6281 v->dtdv_type.dtdt_size : sizeof (uint64_t),
6282 regs[rd] ? DTRACE_DYNVAR_ALLOC :
6283 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
6284
6285 /*
6286 * Given that we're storing to thread-local data,
6287 * we need to flush our predicate cache.
6288 */
6289 curthread->t_predcache = DTRACE_CACHEIDNONE;
6290
6291 if (dvar == NULL)
6292 break;
6293
6294 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6295 size_t lim;
6296
6297 if (!dtrace_vcanload(
6298 (void *)(uintptr_t)regs[rd],
6299 &v->dtdv_type, &lim, mstate, vstate))
6300 break;
6301
6302 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6303 dvar->dtdv_data, &v->dtdv_type, lim);
6304 } else {
6305 *((uint64_t *)dvar->dtdv_data) = regs[rd];
6306 }
6307
6308 break;
6309 }
6310
6311 case DIF_OP_SRA:
6312 regs[rd] = (int64_t)regs[r1] >> regs[r2];
6313 break;
6314
6315 case DIF_OP_CALL:
6316 dtrace_dif_subr(DIF_INSTR_SUBR(instr), rd,
6317 regs, tupregs, ttop, mstate, state);
6318 break;
6319
6320 case DIF_OP_PUSHTR:
6321 if (ttop == DIF_DTR_NREGS) {
6322 *flags |= CPU_DTRACE_TUPOFLOW;
6323 break;
6324 }
6325
6326 if (r1 == DIF_TYPE_STRING) {
6327 /*
6328 * If this is a string type and the size is 0,
6329 * we'll use the system-wide default string
6330 * size. Note that we are _not_ looking at
6331 * the value of the DTRACEOPT_STRSIZE option;
6332 * had this been set, we would expect to have
6333 * a non-zero size value in the "pushtr".
6334 */
6335 tupregs[ttop].dttk_size =
6336 dtrace_strlen((char *)(uintptr_t)regs[rd],
6337 regs[r2] ? regs[r2] :
6338 dtrace_strsize_default) + 1;
6339 } else {
6340 if (regs[r2] > LONG_MAX) {
6341 *flags |= CPU_DTRACE_ILLOP;
6342 break;
6343 }
6344
6345 tupregs[ttop].dttk_size = regs[r2];
6346 }
6347
6348 tupregs[ttop++].dttk_value = regs[rd];
6349 break;
6350
6351 case DIF_OP_PUSHTV:
6352 if (ttop == DIF_DTR_NREGS) {
6353 *flags |= CPU_DTRACE_TUPOFLOW;
6354 break;
6355 }
6356
6357 tupregs[ttop].dttk_value = regs[rd];
6358 tupregs[ttop++].dttk_size = 0;
6359 break;
6360
6361 case DIF_OP_POPTS:
6362 if (ttop != 0)
6363 ttop--;
6364 break;
6365
6366 case DIF_OP_FLUSHTS:
6367 ttop = 0;
6368 break;
6369
6370 case DIF_OP_LDGAA:
6371 case DIF_OP_LDTAA: {
6372 dtrace_dynvar_t *dvar;
6373 dtrace_key_t *key = tupregs;
6374 uint_t nkeys = ttop;
6375
6376 id = DIF_INSTR_VAR(instr);
6377 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6378 id -= DIF_VAR_OTHER_UBASE;
6379
6380 key[nkeys].dttk_value = (uint64_t)id;
6381 key[nkeys++].dttk_size = 0;
6382
6383 if (DIF_INSTR_OP(instr) == DIF_OP_LDTAA) {
6384 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
6385 key[nkeys++].dttk_size = 0;
6386 VERIFY(id < vstate->dtvs_ntlocals);
6387 v = &vstate->dtvs_tlocals[id];
6388 } else {
6389 VERIFY(id < vstate->dtvs_nglobals);
6390 v = &vstate->dtvs_globals[id]->dtsv_var;
6391 }
6392
6393 dvar = dtrace_dynvar(dstate, nkeys, key,
6394 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
6395 v->dtdv_type.dtdt_size : sizeof (uint64_t),
6396 DTRACE_DYNVAR_NOALLOC, mstate, vstate);
6397
6398 if (dvar == NULL) {
6399 regs[rd] = 0;
6400 break;
6401 }
6402
6403 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6404 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
6405 } else {
6406 regs[rd] = *((uint64_t *)dvar->dtdv_data);
6407 }
6408
6409 break;
6410 }
6411
6412 case DIF_OP_STGAA:
6413 case DIF_OP_STTAA: {
6414 dtrace_dynvar_t *dvar;
6415 dtrace_key_t *key = tupregs;
6416 uint_t nkeys = ttop;
6417
6418 id = DIF_INSTR_VAR(instr);
6419 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6420 id -= DIF_VAR_OTHER_UBASE;
6421
6422 key[nkeys].dttk_value = (uint64_t)id;
6423 key[nkeys++].dttk_size = 0;
6424
6425 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) {
6426 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
6427 key[nkeys++].dttk_size = 0;
6428 VERIFY(id < vstate->dtvs_ntlocals);
6429 v = &vstate->dtvs_tlocals[id];
6430 } else {
6431 VERIFY(id < vstate->dtvs_nglobals);
6432 v = &vstate->dtvs_globals[id]->dtsv_var;
6433 }
6434
6435 dvar = dtrace_dynvar(dstate, nkeys, key,
6436 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
6437 v->dtdv_type.dtdt_size : sizeof (uint64_t),
6438 regs[rd] ? DTRACE_DYNVAR_ALLOC :
6439 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
6440
6441 if (dvar == NULL)
6442 break;
6443
6444 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6445 size_t lim;
6446
6447 if (!dtrace_vcanload(
6448 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
6449 &lim, mstate, vstate))
6450 break;
6451
6452 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6453 dvar->dtdv_data, &v->dtdv_type, lim);
6454 } else {
6455 *((uint64_t *)dvar->dtdv_data) = regs[rd];
6456 }
6457
6458 break;
6459 }
6460
6461 case DIF_OP_ALLOCS: {
6462 uintptr_t ptr = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
6463 size_t size = ptr - mstate->dtms_scratch_ptr + regs[r1];
6464
6465 /*
6466 * Rounding up the user allocation size could have
6467 * overflowed large, bogus allocations (like -1ULL) to
6468 * 0.
6469 */
6470 if (size < regs[r1] ||
6471 !DTRACE_INSCRATCH(mstate, size)) {
6472 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
6473 regs[rd] = 0;
6474 break;
6475 }
6476
6477 dtrace_bzero((void *) mstate->dtms_scratch_ptr, size);
6478 mstate->dtms_scratch_ptr += size;
6479 regs[rd] = ptr;
6480 break;
6481 }
6482
6483 case DIF_OP_COPYS:
6484 if (!dtrace_canstore(regs[rd], regs[r2],
6485 mstate, vstate)) {
6486 *flags |= CPU_DTRACE_BADADDR;
6487 *illval = regs[rd];
6488 break;
6489 }
6490
6491 if (!dtrace_canload(regs[r1], regs[r2], mstate, vstate))
6492 break;
6493
6494 dtrace_bcopy((void *)(uintptr_t)regs[r1],
6495 (void *)(uintptr_t)regs[rd], (size_t)regs[r2]);
6496 break;
6497
6498 case DIF_OP_STB:
6499 if (!dtrace_canstore(regs[rd], 1, mstate, vstate)) {
6500 *flags |= CPU_DTRACE_BADADDR;
6501 *illval = regs[rd];
6502 break;
6503 }
6504 *((uint8_t *)(uintptr_t)regs[rd]) = (uint8_t)regs[r1];
6505 break;
6506
6507 case DIF_OP_STH:
6508 if (!dtrace_canstore(regs[rd], 2, mstate, vstate)) {
6509 *flags |= CPU_DTRACE_BADADDR;
6510 *illval = regs[rd];
6511 break;
6512 }
6513 if (regs[rd] & 1) {
6514 *flags |= CPU_DTRACE_BADALIGN;
6515 *illval = regs[rd];
6516 break;
6517 }
6518 *((uint16_t *)(uintptr_t)regs[rd]) = (uint16_t)regs[r1];
6519 break;
6520
6521 case DIF_OP_STW:
6522 if (!dtrace_canstore(regs[rd], 4, mstate, vstate)) {
6523 *flags |= CPU_DTRACE_BADADDR;
6524 *illval = regs[rd];
6525 break;
6526 }
6527 if (regs[rd] & 3) {
6528 *flags |= CPU_DTRACE_BADALIGN;
6529 *illval = regs[rd];
6530 break;
6531 }
6532 *((uint32_t *)(uintptr_t)regs[rd]) = (uint32_t)regs[r1];
6533 break;
6534
6535 case DIF_OP_STX:
6536 if (!dtrace_canstore(regs[rd], 8, mstate, vstate)) {
6537 *flags |= CPU_DTRACE_BADADDR;
6538 *illval = regs[rd];
6539 break;
6540 }
6541 if (regs[rd] & 7) {
6542 *flags |= CPU_DTRACE_BADALIGN;
6543 *illval = regs[rd];
6544 break;
6545 }
6546 *((uint64_t *)(uintptr_t)regs[rd]) = regs[r1];
6547 break;
6548 }
6549 }
6550
6551 if (!(*flags & CPU_DTRACE_FAULT))
6552 return (rval);
6553
6554 mstate->dtms_fltoffs = opc * sizeof (dif_instr_t);
6555 mstate->dtms_present |= DTRACE_MSTATE_FLTOFFS;
6556
6557 return (0);
6558 }
6559
6560 static void
6561 dtrace_action_breakpoint(dtrace_ecb_t *ecb)
6562 {
6563 dtrace_probe_t *probe = ecb->dte_probe;
6564 dtrace_provider_t *prov = probe->dtpr_provider;
6565 char c[DTRACE_FULLNAMELEN + 80], *str;
6566 char *msg = "dtrace: breakpoint action at probe ";
6567 char *ecbmsg = " (ecb ";
6568 uintptr_t mask = (0xf << (sizeof (uintptr_t) * NBBY / 4));
6569 uintptr_t val = (uintptr_t)ecb;
6570 int shift = (sizeof (uintptr_t) * NBBY) - 4, i = 0;
6571
6572 if (dtrace_destructive_disallow)
6573 return;
6574
6575 /*
6576 * It's impossible to be taking action on the NULL probe.
6577 */
6578 ASSERT(probe != NULL);
6579
6580 /*
6581 * This is a poor man's (destitute man's?) sprintf(): we want to
6582 * print the provider name, module name, function name and name of
6583 * the probe, along with the hex address of the ECB with the breakpoint
6584 * action -- all of which we must place in the character buffer by
6585 * hand.
6586 */
6587 while (*msg != '\0')
6588 c[i++] = *msg++;
6589
6590 for (str = prov->dtpv_name; *str != '\0'; str++)
6591 c[i++] = *str;
6592 c[i++] = ':';
6593
6594 for (str = probe->dtpr_mod; *str != '\0'; str++)
6595 c[i++] = *str;
6596 c[i++] = ':';
6597
6598 for (str = probe->dtpr_func; *str != '\0'; str++)
6599 c[i++] = *str;
6600 c[i++] = ':';
6601
6602 for (str = probe->dtpr_name; *str != '\0'; str++)
6603 c[i++] = *str;
6604
6605 while (*ecbmsg != '\0')
6606 c[i++] = *ecbmsg++;
6607
6608 while (shift >= 0) {
6609 mask = (uintptr_t)0xf << shift;
6610
6611 if (val >= ((uintptr_t)1 << shift))
6612 c[i++] = "0123456789abcdef"[(val & mask) >> shift];
6613 shift -= 4;
6614 }
6615
6616 c[i++] = ')';
6617 c[i] = '\0';
6618
6619 debug_enter(c);
6620 }
6621
6622 static void
6623 dtrace_action_panic(dtrace_ecb_t *ecb)
6624 {
6625 dtrace_probe_t *probe = ecb->dte_probe;
6626
6627 /*
6628 * It's impossible to be taking action on the NULL probe.
6629 */
6630 ASSERT(probe != NULL);
6631
6632 if (dtrace_destructive_disallow)
6633 return;
6634
6635 if (dtrace_panicked != NULL)
6636 return;
6637
6638 if (dtrace_casptr(&dtrace_panicked, NULL, curthread) != NULL)
6639 return;
6640
6641 /*
6642 * We won the right to panic. (We want to be sure that only one
6643 * thread calls panic() from dtrace_probe(), and that panic() is
6644 * called exactly once.)
6645 */
6646 dtrace_panic("dtrace: panic action at probe %s:%s:%s:%s (ecb %p)",
6647 probe->dtpr_provider->dtpv_name, probe->dtpr_mod,
6648 probe->dtpr_func, probe->dtpr_name, (void *)ecb);
6649 }
6650
6651 static void
6652 dtrace_action_raise(uint64_t sig)
6653 {
6654 if (dtrace_destructive_disallow)
6655 return;
6656
6657 if (sig >= NSIG) {
6658 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
6659 return;
6660 }
6661
6662 /*
6663 * raise() has a queue depth of 1 -- we ignore all subsequent
6664 * invocations of the raise() action.
6665 */
6666 if (curthread->t_dtrace_sig == 0)
6667 curthread->t_dtrace_sig = (uint8_t)sig;
6668
6669 curthread->t_sig_check = 1;
6670 aston(curthread);
6671 }
6672
6673 static void
6674 dtrace_action_stop(void)
6675 {
6676 if (dtrace_destructive_disallow)
6677 return;
6678
6679 if (!curthread->t_dtrace_stop) {
6680 curthread->t_dtrace_stop = 1;
6681 curthread->t_sig_check = 1;
6682 aston(curthread);
6683 }
6684 }
6685
6686 static void
6687 dtrace_action_chill(dtrace_mstate_t *mstate, hrtime_t val)
6688 {
6689 hrtime_t now;
6690 volatile uint16_t *flags;
6691 cpu_t *cpu = CPU;
6692
6693 if (dtrace_destructive_disallow)
6694 return;
6695
6696 flags = (volatile uint16_t *)&cpu_core[cpu->cpu_id].cpuc_dtrace_flags;
6697
6698 now = dtrace_gethrtime();
6699
6700 if (now - cpu->cpu_dtrace_chillmark > dtrace_chill_interval) {
6701 /*
6702 * We need to advance the mark to the current time.
6703 */
6704 cpu->cpu_dtrace_chillmark = now;
6705 cpu->cpu_dtrace_chilled = 0;
6706 }
6707
6708 /*
6709 * Now check to see if the requested chill time would take us over
6710 * the maximum amount of time allowed in the chill interval. (Or
6711 * worse, if the calculation itself induces overflow.)
6712 */
6713 if (cpu->cpu_dtrace_chilled + val > dtrace_chill_max ||
6714 cpu->cpu_dtrace_chilled + val < cpu->cpu_dtrace_chilled) {
6715 *flags |= CPU_DTRACE_ILLOP;
6716 return;
6717 }
6718
6719 while (dtrace_gethrtime() - now < val)
6720 continue;
6721
6722 /*
6723 * Normally, we assure that the value of the variable "timestamp" does
6724 * not change within an ECB. The presence of chill() represents an
6725 * exception to this rule, however.
6726 */
6727 mstate->dtms_present &= ~DTRACE_MSTATE_TIMESTAMP;
6728 cpu->cpu_dtrace_chilled += val;
6729 }
6730
6731 static void
6732 dtrace_action_ustack(dtrace_mstate_t *mstate, dtrace_state_t *state,
6733 uint64_t *buf, uint64_t arg)
6734 {
6735 int nframes = DTRACE_USTACK_NFRAMES(arg);
6736 int strsize = DTRACE_USTACK_STRSIZE(arg);
6737 uint64_t *pcs = &buf[1], *fps;
6738 char *str = (char *)&pcs[nframes];
6739 int size, offs = 0, i, j;
6740 size_t rem;
6741 uintptr_t old = mstate->dtms_scratch_ptr, saved;
6742 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
6743 char *sym;
6744
6745 /*
6746 * Should be taking a faster path if string space has not been
6747 * allocated.
6748 */
6749 ASSERT(strsize != 0);
6750
6751 /*
6752 * We will first allocate some temporary space for the frame pointers.
6753 */
6754 fps = (uint64_t *)P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
6755 size = (uintptr_t)fps - mstate->dtms_scratch_ptr +
6756 (nframes * sizeof (uint64_t));
6757
6758 if (!DTRACE_INSCRATCH(mstate, size)) {
6759 /*
6760 * Not enough room for our frame pointers -- need to indicate
6761 * that we ran out of scratch space.
6762 */
6763 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
6764 return;
6765 }
6766
6767 mstate->dtms_scratch_ptr += size;
6768 saved = mstate->dtms_scratch_ptr;
6769
6770 /*
6771 * Now get a stack with both program counters and frame pointers.
6772 */
6773 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6774 dtrace_getufpstack(buf, fps, nframes + 1);
6775 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6776
6777 /*
6778 * If that faulted, we're cooked.
6779 */
6780 if (*flags & CPU_DTRACE_FAULT)
6781 goto out;
6782
6783 /*
6784 * Now we want to walk up the stack, calling the USTACK helper. For
6785 * each iteration, we restore the scratch pointer.
6786 */
6787 for (i = 0; i < nframes; i++) {
6788 mstate->dtms_scratch_ptr = saved;
6789
6790 if (offs >= strsize)
6791 break;
6792
6793 sym = (char *)(uintptr_t)dtrace_helper(
6794 DTRACE_HELPER_ACTION_USTACK,
6795 mstate, state, pcs[i], fps[i]);
6796
6797 /*
6798 * If we faulted while running the helper, we're going to
6799 * clear the fault and null out the corresponding string.
6800 */
6801 if (*flags & CPU_DTRACE_FAULT) {
6802 *flags &= ~CPU_DTRACE_FAULT;
6803 str[offs++] = '\0';
6804 continue;
6805 }
6806
6807 if (sym == NULL) {
6808 str[offs++] = '\0';
6809 continue;
6810 }
6811
6812 if (!dtrace_strcanload((uintptr_t)sym, strsize, &rem, mstate,
6813 &(state->dts_vstate))) {
6814 str[offs++] = '\0';
6815 continue;
6816 }
6817
6818 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6819
6820 /*
6821 * Now copy in the string that the helper returned to us.
6822 */
6823 for (j = 0; offs + j < strsize && j < rem; j++) {
6824 if ((str[offs + j] = sym[j]) == '\0')
6825 break;
6826 }
6827
6828 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6829
6830 offs += j + 1;
6831 }
6832
6833 if (offs >= strsize) {
6834 /*
6835 * If we didn't have room for all of the strings, we don't
6836 * abort processing -- this needn't be a fatal error -- but we
6837 * still want to increment a counter (dts_stkstroverflows) to
6838 * allow this condition to be warned about. (If this is from
6839 * a jstack() action, it is easily tuned via jstackstrsize.)
6840 */
6841 dtrace_error(&state->dts_stkstroverflows);
6842 }
6843
6844 while (offs < strsize)
6845 str[offs++] = '\0';
6846
6847 out:
6848 mstate->dtms_scratch_ptr = old;
6849 }
6850
6851 static void
6852 dtrace_store_by_ref(dtrace_difo_t *dp, caddr_t tomax, size_t size,
6853 size_t *valoffsp, uint64_t *valp, uint64_t end, int intuple, int dtkind)
6854 {
6855 volatile uint16_t *flags;
6856 uint64_t val = *valp;
6857 size_t valoffs = *valoffsp;
6858
6859 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
6860 ASSERT(dtkind == DIF_TF_BYREF || dtkind == DIF_TF_BYUREF);
6861
6862 /*
6863 * If this is a string, we're going to only load until we find the zero
6864 * byte -- after which we'll store zero bytes.
6865 */
6866 if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) {
6867 char c = '\0' + 1;
6868 size_t s;
6869
6870 for (s = 0; s < size; s++) {
6871 if (c != '\0' && dtkind == DIF_TF_BYREF) {
6872 c = dtrace_load8(val++);
6873 } else if (c != '\0' && dtkind == DIF_TF_BYUREF) {
6874 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6875 c = dtrace_fuword8((void *)(uintptr_t)val++);
6876 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6877 if (*flags & CPU_DTRACE_FAULT)
6878 break;
6879 }
6880
6881 DTRACE_STORE(uint8_t, tomax, valoffs++, c);
6882
6883 if (c == '\0' && intuple)
6884 break;
6885 }
6886 } else {
6887 uint8_t c;
6888 while (valoffs < end) {
6889 if (dtkind == DIF_TF_BYREF) {
6890 c = dtrace_load8(val++);
6891 } else if (dtkind == DIF_TF_BYUREF) {
6892 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6893 c = dtrace_fuword8((void *)(uintptr_t)val++);
6894 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6895 if (*flags & CPU_DTRACE_FAULT)
6896 break;
6897 }
6898
6899 DTRACE_STORE(uint8_t, tomax,
6900 valoffs++, c);
6901 }
6902 }
6903
6904 *valp = val;
6905 *valoffsp = valoffs;
6906 }
6907
6908 /*
6909 * If you're looking for the epicenter of DTrace, you just found it. This
6910 * is the function called by the provider to fire a probe -- from which all
6911 * subsequent probe-context DTrace activity emanates.
6912 */
6913 void
6914 dtrace_probe(dtrace_id_t id, uintptr_t arg0, uintptr_t arg1,
6915 uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
6916 {
6917 processorid_t cpuid;
6918 dtrace_icookie_t cookie;
6919 dtrace_probe_t *probe;
6920 dtrace_mstate_t mstate;
6921 dtrace_ecb_t *ecb;
6922 dtrace_action_t *act;
6923 intptr_t offs;
6924 size_t size;
6925 int vtime, onintr;
6926 volatile uint16_t *flags;
6927 hrtime_t now, end;
6928
6929 /*
6930 * Kick out immediately if this CPU is still being born (in which case
6931 * curthread will be set to -1) or the current thread can't allow
6932 * probes in its current context.
6933 */
6934 if (((uintptr_t)curthread & 1) || (curthread->t_flag & T_DONTDTRACE))
6935 return;
6936
6937 cookie = dtrace_interrupt_disable();
6938
6939 /*
6940 * Also refuse to process any probe firings that might happen on a
6941 * disabled CPU.
6942 */
6943 if (CPU->cpu_flags & CPU_DISABLED) {
6944 dtrace_interrupt_enable(cookie);
6945 return;
6946 }
6947
6948 probe = dtrace_probes[id - 1];
6949 cpuid = CPU->cpu_id;
6950 onintr = CPU_ON_INTR(CPU);
6951
6952 CPU->cpu_dtrace_probes++;
6953
6954 if (!onintr && probe->dtpr_predcache != DTRACE_CACHEIDNONE &&
6955 probe->dtpr_predcache == curthread->t_predcache) {
6956 /*
6957 * We have hit in the predicate cache; we know that
6958 * this predicate would evaluate to be false.
6959 */
6960 dtrace_interrupt_enable(cookie);
6961 return;
6962 }
6963
6964 if (panic_quiesce) {
6965 /*
6966 * We don't trace anything if we're panicking.
6967 */
6968 dtrace_interrupt_enable(cookie);
6969 return;
6970 }
6971
6972 now = mstate.dtms_timestamp = dtrace_gethrtime();
6973 mstate.dtms_present |= DTRACE_MSTATE_TIMESTAMP;
6974 vtime = dtrace_vtime_references != 0;
6975
6976 if (vtime && curthread->t_dtrace_start)
6977 curthread->t_dtrace_vtime += now - curthread->t_dtrace_start;
6978
6979 mstate.dtms_difo = NULL;
6980 mstate.dtms_probe = probe;
6981 mstate.dtms_strtok = 0;
6982 mstate.dtms_arg[0] = arg0;
6983 mstate.dtms_arg[1] = arg1;
6984 mstate.dtms_arg[2] = arg2;
6985 mstate.dtms_arg[3] = arg3;
6986 mstate.dtms_arg[4] = arg4;
6987
6988 flags = (volatile uint16_t *)&cpu_core[cpuid].cpuc_dtrace_flags;
6989
6990 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
6991 dtrace_predicate_t *pred = ecb->dte_predicate;
6992 dtrace_state_t *state = ecb->dte_state;
6993 dtrace_buffer_t *buf = &state->dts_buffer[cpuid];
6994 dtrace_buffer_t *aggbuf = &state->dts_aggbuffer[cpuid];
6995 dtrace_vstate_t *vstate = &state->dts_vstate;
6996 dtrace_provider_t *prov = probe->dtpr_provider;
6997 uint64_t tracememsize = 0;
6998 int committed = 0;
6999 caddr_t tomax;
7000
7001 /*
7002 * A little subtlety with the following (seemingly innocuous)
7003 * declaration of the automatic 'val': by looking at the
7004 * code, you might think that it could be declared in the
7005 * action processing loop, below. (That is, it's only used in
7006 * the action processing loop.) However, it must be declared
7007 * out of that scope because in the case of DIF expression
7008 * arguments to aggregating actions, one iteration of the
7009 * action loop will use the last iteration's value.
7010 */
7011 #ifdef lint
7012 uint64_t val = 0;
7013 #else
7014 uint64_t val;
7015 #endif
7016
7017 mstate.dtms_present = DTRACE_MSTATE_ARGS | DTRACE_MSTATE_PROBE;
7018 mstate.dtms_access = DTRACE_ACCESS_ARGS | DTRACE_ACCESS_PROC;
7019 mstate.dtms_getf = NULL;
7020
7021 *flags &= ~CPU_DTRACE_ERROR;
7022
7023 if (prov == dtrace_provider) {
7024 /*
7025 * If dtrace itself is the provider of this probe,
7026 * we're only going to continue processing the ECB if
7027 * arg0 (the dtrace_state_t) is equal to the ECB's
7028 * creating state. (This prevents disjoint consumers
7029 * from seeing one another's metaprobes.)
7030 */
7031 if (arg0 != (uint64_t)(uintptr_t)state)
7032 continue;
7033 }
7034
7035 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) {
7036 /*
7037 * We're not currently active. If our provider isn't
7038 * the dtrace pseudo provider, we're not interested.
7039 */
7040 if (prov != dtrace_provider)
7041 continue;
7042
7043 /*
7044 * Now we must further check if we are in the BEGIN
7045 * probe. If we are, we will only continue processing
7046 * if we're still in WARMUP -- if one BEGIN enabling
7047 * has invoked the exit() action, we don't want to
7048 * evaluate subsequent BEGIN enablings.
7049 */
7050 if (probe->dtpr_id == dtrace_probeid_begin &&
7051 state->dts_activity != DTRACE_ACTIVITY_WARMUP) {
7052 ASSERT(state->dts_activity ==
7053 DTRACE_ACTIVITY_DRAINING);
7054 continue;
7055 }
7056 }
7057
7058 if (ecb->dte_cond && !dtrace_priv_probe(state, &mstate, ecb))
7059 continue;
7060
7061 if (now - state->dts_alive > dtrace_deadman_timeout) {
7062 /*
7063 * We seem to be dead. Unless we (a) have kernel
7064 * destructive permissions (b) have explicitly enabled
7065 * destructive actions and (c) destructive actions have
7066 * not been disabled, we're going to transition into
7067 * the KILLED state, from which no further processing
7068 * on this state will be performed.
7069 */
7070 if (!dtrace_priv_kernel_destructive(state) ||
7071 !state->dts_cred.dcr_destructive ||
7072 dtrace_destructive_disallow) {
7073 void *activity = &state->dts_activity;
7074 dtrace_activity_t current;
7075
7076 do {
7077 current = state->dts_activity;
7078 } while (dtrace_cas32(activity, current,
7079 DTRACE_ACTIVITY_KILLED) != current);
7080
7081 continue;
7082 }
7083 }
7084
7085 if ((offs = dtrace_buffer_reserve(buf, ecb->dte_needed,
7086 ecb->dte_alignment, state, &mstate)) < 0)
7087 continue;
7088
7089 tomax = buf->dtb_tomax;
7090 ASSERT(tomax != NULL);
7091
7092 if (ecb->dte_size != 0) {
7093 dtrace_rechdr_t dtrh;
7094 if (!(mstate.dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
7095 mstate.dtms_timestamp = dtrace_gethrtime();
7096 mstate.dtms_present |= DTRACE_MSTATE_TIMESTAMP;
7097 }
7098 ASSERT3U(ecb->dte_size, >=, sizeof (dtrace_rechdr_t));
7099 dtrh.dtrh_epid = ecb->dte_epid;
7100 DTRACE_RECORD_STORE_TIMESTAMP(&dtrh,
7101 mstate.dtms_timestamp);
7102 *((dtrace_rechdr_t *)(tomax + offs)) = dtrh;
7103 }
7104
7105 mstate.dtms_epid = ecb->dte_epid;
7106 mstate.dtms_present |= DTRACE_MSTATE_EPID;
7107
7108 if (state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)
7109 mstate.dtms_access |= DTRACE_ACCESS_KERNEL;
7110
7111 if (pred != NULL) {
7112 dtrace_difo_t *dp = pred->dtp_difo;
7113 int rval;
7114
7115 rval = dtrace_dif_emulate(dp, &mstate, vstate, state);
7116
7117 if (!(*flags & CPU_DTRACE_ERROR) && !rval) {
7118 dtrace_cacheid_t cid = probe->dtpr_predcache;
7119
7120 if (cid != DTRACE_CACHEIDNONE && !onintr) {
7121 /*
7122 * Update the predicate cache...
7123 */
7124 ASSERT(cid == pred->dtp_cacheid);
7125 curthread->t_predcache = cid;
7126 }
7127
7128 continue;
7129 }
7130 }
7131
7132 for (act = ecb->dte_action; !(*flags & CPU_DTRACE_ERROR) &&
7133 act != NULL; act = act->dta_next) {
7134 size_t valoffs;
7135 dtrace_difo_t *dp;
7136 dtrace_recdesc_t *rec = &act->dta_rec;
7137
7138 size = rec->dtrd_size;
7139 valoffs = offs + rec->dtrd_offset;
7140
7141 if (DTRACEACT_ISAGG(act->dta_kind)) {
7142 uint64_t v = 0xbad;
7143 dtrace_aggregation_t *agg;
7144
7145 agg = (dtrace_aggregation_t *)act;
7146
7147 if ((dp = act->dta_difo) != NULL)
7148 v = dtrace_dif_emulate(dp,
7149 &mstate, vstate, state);
7150
7151 if (*flags & CPU_DTRACE_ERROR)
7152 continue;
7153
7154 /*
7155 * Note that we always pass the expression
7156 * value from the previous iteration of the
7157 * action loop. This value will only be used
7158 * if there is an expression argument to the
7159 * aggregating action, denoted by the
7160 * dtag_hasarg field.
7161 */
7162 dtrace_aggregate(agg, buf,
7163 offs, aggbuf, v, val);
7164 continue;
7165 }
7166
7167 switch (act->dta_kind) {
7168 case DTRACEACT_STOP:
7169 if (dtrace_priv_proc_destructive(state,
7170 &mstate))
7171 dtrace_action_stop();
7172 continue;
7173
7174 case DTRACEACT_BREAKPOINT:
7175 if (dtrace_priv_kernel_destructive(state))
7176 dtrace_action_breakpoint(ecb);
7177 continue;
7178
7179 case DTRACEACT_PANIC:
7180 if (dtrace_priv_kernel_destructive(state))
7181 dtrace_action_panic(ecb);
7182 continue;
7183
7184 case DTRACEACT_STACK:
7185 if (!dtrace_priv_kernel(state))
7186 continue;
7187
7188 dtrace_getpcstack((pc_t *)(tomax + valoffs),
7189 size / sizeof (pc_t), probe->dtpr_aframes,
7190 DTRACE_ANCHORED(probe) ? NULL :
7191 (uint32_t *)arg0);
7192
7193 continue;
7194
7195 case DTRACEACT_JSTACK:
7196 case DTRACEACT_USTACK:
7197 if (!dtrace_priv_proc(state, &mstate))
7198 continue;
7199
7200 /*
7201 * See comment in DIF_VAR_PID.
7202 */
7203 if (DTRACE_ANCHORED(mstate.dtms_probe) &&
7204 CPU_ON_INTR(CPU)) {
7205 int depth = DTRACE_USTACK_NFRAMES(
7206 rec->dtrd_arg) + 1;
7207
7208 dtrace_bzero((void *)(tomax + valoffs),
7209 DTRACE_USTACK_STRSIZE(rec->dtrd_arg)
7210 + depth * sizeof (uint64_t));
7211
7212 continue;
7213 }
7214
7215 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0 &&
7216 curproc->p_dtrace_helpers != NULL) {
7217 /*
7218 * This is the slow path -- we have
7219 * allocated string space, and we're
7220 * getting the stack of a process that
7221 * has helpers. Call into a separate
7222 * routine to perform this processing.
7223 */
7224 dtrace_action_ustack(&mstate, state,
7225 (uint64_t *)(tomax + valoffs),
7226 rec->dtrd_arg);
7227 continue;
7228 }
7229
7230 /*
7231 * Clear the string space, since there's no
7232 * helper to do it for us.
7233 */
7234 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0) {
7235 int depth = DTRACE_USTACK_NFRAMES(
7236 rec->dtrd_arg);
7237 size_t strsize = DTRACE_USTACK_STRSIZE(
7238 rec->dtrd_arg);
7239 uint64_t *buf = (uint64_t *)(tomax +
7240 valoffs);
7241 void *strspace = &buf[depth + 1];
7242
7243 dtrace_bzero(strspace,
7244 MIN(depth, strsize));
7245 }
7246
7247 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
7248 dtrace_getupcstack((uint64_t *)
7249 (tomax + valoffs),
7250 DTRACE_USTACK_NFRAMES(rec->dtrd_arg) + 1);
7251 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
7252 continue;
7253
7254 default:
7255 break;
7256 }
7257
7258 dp = act->dta_difo;
7259 ASSERT(dp != NULL);
7260
7261 val = dtrace_dif_emulate(dp, &mstate, vstate, state);
7262
7263 if (*flags & CPU_DTRACE_ERROR)
7264 continue;
7265
7266 switch (act->dta_kind) {
7267 case DTRACEACT_SPECULATE: {
7268 dtrace_rechdr_t *dtrh;
7269
7270 ASSERT(buf == &state->dts_buffer[cpuid]);
7271 buf = dtrace_speculation_buffer(state,
7272 cpuid, val);
7273
7274 if (buf == NULL) {
7275 *flags |= CPU_DTRACE_DROP;
7276 continue;
7277 }
7278
7279 offs = dtrace_buffer_reserve(buf,
7280 ecb->dte_needed, ecb->dte_alignment,
7281 state, NULL);
7282
7283 if (offs < 0) {
7284 *flags |= CPU_DTRACE_DROP;
7285 continue;
7286 }
7287
7288 tomax = buf->dtb_tomax;
7289 ASSERT(tomax != NULL);
7290
7291 if (ecb->dte_size == 0)
7292 continue;
7293
7294 ASSERT3U(ecb->dte_size, >=,
7295 sizeof (dtrace_rechdr_t));
7296 dtrh = ((void *)(tomax + offs));
7297 dtrh->dtrh_epid = ecb->dte_epid;
7298 /*
7299 * When the speculation is committed, all of
7300 * the records in the speculative buffer will
7301 * have their timestamps set to the commit
7302 * time. Until then, it is set to a sentinel
7303 * value, for debugability.
7304 */
7305 DTRACE_RECORD_STORE_TIMESTAMP(dtrh, UINT64_MAX);
7306 continue;
7307 }
7308
7309 case DTRACEACT_CHILL:
7310 if (dtrace_priv_kernel_destructive(state))
7311 dtrace_action_chill(&mstate, val);
7312 continue;
7313
7314 case DTRACEACT_RAISE:
7315 if (dtrace_priv_proc_destructive(state,
7316 &mstate))
7317 dtrace_action_raise(val);
7318 continue;
7319
7320 case DTRACEACT_COMMIT:
7321 ASSERT(!committed);
7322
7323 /*
7324 * We need to commit our buffer state.
7325 */
7326 if (ecb->dte_size)
7327 buf->dtb_offset = offs + ecb->dte_size;
7328 buf = &state->dts_buffer[cpuid];
7329 dtrace_speculation_commit(state, cpuid, val);
7330 committed = 1;
7331 continue;
7332
7333 case DTRACEACT_DISCARD:
7334 dtrace_speculation_discard(state, cpuid, val);
7335 continue;
7336
7337 case DTRACEACT_DIFEXPR:
7338 case DTRACEACT_LIBACT:
7339 case DTRACEACT_PRINTF:
7340 case DTRACEACT_PRINTA:
7341 case DTRACEACT_SYSTEM:
7342 case DTRACEACT_FREOPEN:
7343 case DTRACEACT_TRACEMEM:
7344 break;
7345
7346 case DTRACEACT_TRACEMEM_DYNSIZE:
7347 tracememsize = val;
7348 break;
7349
7350 case DTRACEACT_SYM:
7351 case DTRACEACT_MOD:
7352 if (!dtrace_priv_kernel(state))
7353 continue;
7354 break;
7355
7356 case DTRACEACT_USYM:
7357 case DTRACEACT_UMOD:
7358 case DTRACEACT_UADDR: {
7359 struct pid *pid = curthread->t_procp->p_pidp;
7360
7361 if (!dtrace_priv_proc(state, &mstate))
7362 continue;
7363
7364 DTRACE_STORE(uint64_t, tomax,
7365 valoffs, (uint64_t)pid->pid_id);
7366 DTRACE_STORE(uint64_t, tomax,
7367 valoffs + sizeof (uint64_t), val);
7368
7369 continue;
7370 }
7371
7372 case DTRACEACT_EXIT: {
7373 /*
7374 * For the exit action, we are going to attempt
7375 * to atomically set our activity to be
7376 * draining. If this fails (either because
7377 * another CPU has beat us to the exit action,
7378 * or because our current activity is something
7379 * other than ACTIVE or WARMUP), we will
7380 * continue. This assures that the exit action
7381 * can be successfully recorded at most once
7382 * when we're in the ACTIVE state. If we're
7383 * encountering the exit() action while in
7384 * COOLDOWN, however, we want to honor the new
7385 * status code. (We know that we're the only
7386 * thread in COOLDOWN, so there is no race.)
7387 */
7388 void *activity = &state->dts_activity;
7389 dtrace_activity_t current = state->dts_activity;
7390
7391 if (current == DTRACE_ACTIVITY_COOLDOWN)
7392 break;
7393
7394 if (current != DTRACE_ACTIVITY_WARMUP)
7395 current = DTRACE_ACTIVITY_ACTIVE;
7396
7397 if (dtrace_cas32(activity, current,
7398 DTRACE_ACTIVITY_DRAINING) != current) {
7399 *flags |= CPU_DTRACE_DROP;
7400 continue;
7401 }
7402
7403 break;
7404 }
7405
7406 default:
7407 ASSERT(0);
7408 }
7409
7410 if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF ||
7411 dp->dtdo_rtype.dtdt_flags & DIF_TF_BYUREF) {
7412 uintptr_t end = valoffs + size;
7413
7414 if (tracememsize != 0 &&
7415 valoffs + tracememsize < end) {
7416 end = valoffs + tracememsize;
7417 tracememsize = 0;
7418 }
7419
7420 if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF &&
7421 !dtrace_vcanload((void *)(uintptr_t)val,
7422 &dp->dtdo_rtype, NULL, &mstate, vstate))
7423 continue;
7424
7425 dtrace_store_by_ref(dp, tomax, size, &valoffs,
7426 &val, end, act->dta_intuple,
7427 dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF ?
7428 DIF_TF_BYREF: DIF_TF_BYUREF);
7429 continue;
7430 }
7431
7432 switch (size) {
7433 case 0:
7434 break;
7435
7436 case sizeof (uint8_t):
7437 DTRACE_STORE(uint8_t, tomax, valoffs, val);
7438 break;
7439 case sizeof (uint16_t):
7440 DTRACE_STORE(uint16_t, tomax, valoffs, val);
7441 break;
7442 case sizeof (uint32_t):
7443 DTRACE_STORE(uint32_t, tomax, valoffs, val);
7444 break;
7445 case sizeof (uint64_t):
7446 DTRACE_STORE(uint64_t, tomax, valoffs, val);
7447 break;
7448 default:
7449 /*
7450 * Any other size should have been returned by
7451 * reference, not by value.
7452 */
7453 ASSERT(0);
7454 break;
7455 }
7456 }
7457
7458 if (*flags & CPU_DTRACE_DROP)
7459 continue;
7460
7461 if (*flags & CPU_DTRACE_FAULT) {
7462 int ndx;
7463 dtrace_action_t *err;
7464
7465 buf->dtb_errors++;
7466
7467 if (probe->dtpr_id == dtrace_probeid_error) {
7468 /*
7469 * There's nothing we can do -- we had an
7470 * error on the error probe. We bump an
7471 * error counter to at least indicate that
7472 * this condition happened.
7473 */
7474 dtrace_error(&state->dts_dblerrors);
7475 continue;
7476 }
7477
7478 if (vtime) {
7479 /*
7480 * Before recursing on dtrace_probe(), we
7481 * need to explicitly clear out our start
7482 * time to prevent it from being accumulated
7483 * into t_dtrace_vtime.
7484 */
7485 curthread->t_dtrace_start = 0;
7486 }
7487
7488 /*
7489 * Iterate over the actions to figure out which action
7490 * we were processing when we experienced the error.
7491 * Note that act points _past_ the faulting action; if
7492 * act is ecb->dte_action, the fault was in the
7493 * predicate, if it's ecb->dte_action->dta_next it's
7494 * in action #1, and so on.
7495 */
7496 for (err = ecb->dte_action, ndx = 0;
7497 err != act; err = err->dta_next, ndx++)
7498 continue;
7499
7500 dtrace_probe_error(state, ecb->dte_epid, ndx,
7501 (mstate.dtms_present & DTRACE_MSTATE_FLTOFFS) ?
7502 mstate.dtms_fltoffs : -1, DTRACE_FLAGS2FLT(*flags),
7503 cpu_core[cpuid].cpuc_dtrace_illval);
7504
7505 continue;
7506 }
7507
7508 if (!committed)
7509 buf->dtb_offset = offs + ecb->dte_size;
7510 }
7511
7512 end = dtrace_gethrtime();
7513 if (vtime)
7514 curthread->t_dtrace_start = end;
7515
7516 CPU->cpu_dtrace_nsec += end - now;
7517
7518 dtrace_interrupt_enable(cookie);
7519 }
7520
7521 /*
7522 * DTrace Probe Hashing Functions
7523 *
7524 * The functions in this section (and indeed, the functions in remaining
7525 * sections) are not _called_ from probe context. (Any exceptions to this are
7526 * marked with a "Note:".) Rather, they are called from elsewhere in the
7527 * DTrace framework to look-up probes in, add probes to and remove probes from
7528 * the DTrace probe hashes. (Each probe is hashed by each element of the
7529 * probe tuple -- allowing for fast lookups, regardless of what was
7530 * specified.)
7531 */
7532 static uint_t
7533 dtrace_hash_str(char *p)
7534 {
7535 unsigned int g;
7536 uint_t hval = 0;
7537
7538 while (*p) {
7539 hval = (hval << 4) + *p++;
7540 if ((g = (hval & 0xf0000000)) != 0)
7541 hval ^= g >> 24;
7542 hval &= ~g;
7543 }
7544 return (hval);
7545 }
7546
7547 static dtrace_hash_t *
7548 dtrace_hash_create(uintptr_t stroffs, uintptr_t nextoffs, uintptr_t prevoffs)
7549 {
7550 dtrace_hash_t *hash = kmem_zalloc(sizeof (dtrace_hash_t), KM_SLEEP);
7551
7552 hash->dth_stroffs = stroffs;
7553 hash->dth_nextoffs = nextoffs;
7554 hash->dth_prevoffs = prevoffs;
7555
7556 hash->dth_size = 1;
7557 hash->dth_mask = hash->dth_size - 1;
7558
7559 hash->dth_tab = kmem_zalloc(hash->dth_size *
7560 sizeof (dtrace_hashbucket_t *), KM_SLEEP);
7561
7562 return (hash);
7563 }
7564
7565 static void
7566 dtrace_hash_destroy(dtrace_hash_t *hash)
7567 {
7568 #ifdef DEBUG
7569 int i;
7570
7571 for (i = 0; i < hash->dth_size; i++)
7572 ASSERT(hash->dth_tab[i] == NULL);
7573 #endif
7574
7575 kmem_free(hash->dth_tab,
7576 hash->dth_size * sizeof (dtrace_hashbucket_t *));
7577 kmem_free(hash, sizeof (dtrace_hash_t));
7578 }
7579
7580 static void
7581 dtrace_hash_resize(dtrace_hash_t *hash)
7582 {
7583 int size = hash->dth_size, i, ndx;
7584 int new_size = hash->dth_size << 1;
7585 int new_mask = new_size - 1;
7586 dtrace_hashbucket_t **new_tab, *bucket, *next;
7587
7588 ASSERT((new_size & new_mask) == 0);
7589
7590 new_tab = kmem_zalloc(new_size * sizeof (void *), KM_SLEEP);
7591
7592 for (i = 0; i < size; i++) {
7593 for (bucket = hash->dth_tab[i]; bucket != NULL; bucket = next) {
7594 dtrace_probe_t *probe = bucket->dthb_chain;
7595
7596 ASSERT(probe != NULL);
7597 ndx = DTRACE_HASHSTR(hash, probe) & new_mask;
7598
7599 next = bucket->dthb_next;
7600 bucket->dthb_next = new_tab[ndx];
7601 new_tab[ndx] = bucket;
7602 }
7603 }
7604
7605 kmem_free(hash->dth_tab, hash->dth_size * sizeof (void *));
7606 hash->dth_tab = new_tab;
7607 hash->dth_size = new_size;
7608 hash->dth_mask = new_mask;
7609 }
7610
7611 static void
7612 dtrace_hash_add(dtrace_hash_t *hash, dtrace_probe_t *new)
7613 {
7614 int hashval = DTRACE_HASHSTR(hash, new);
7615 int ndx = hashval & hash->dth_mask;
7616 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7617 dtrace_probe_t **nextp, **prevp;
7618
7619 for (; bucket != NULL; bucket = bucket->dthb_next) {
7620 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, new))
7621 goto add;
7622 }
7623
7624 if ((hash->dth_nbuckets >> 1) > hash->dth_size) {
7625 dtrace_hash_resize(hash);
7626 dtrace_hash_add(hash, new);
7627 return;
7628 }
7629
7630 bucket = kmem_zalloc(sizeof (dtrace_hashbucket_t), KM_SLEEP);
7631 bucket->dthb_next = hash->dth_tab[ndx];
7632 hash->dth_tab[ndx] = bucket;
7633 hash->dth_nbuckets++;
7634
7635 add:
7636 nextp = DTRACE_HASHNEXT(hash, new);
7637 ASSERT(*nextp == NULL && *(DTRACE_HASHPREV(hash, new)) == NULL);
7638 *nextp = bucket->dthb_chain;
7639
7640 if (bucket->dthb_chain != NULL) {
7641 prevp = DTRACE_HASHPREV(hash, bucket->dthb_chain);
7642 ASSERT(*prevp == NULL);
7643 *prevp = new;
7644 }
7645
7646 bucket->dthb_chain = new;
7647 bucket->dthb_len++;
7648 }
7649
7650 static dtrace_probe_t *
7651 dtrace_hash_lookup(dtrace_hash_t *hash, dtrace_probe_t *template)
7652 {
7653 int hashval = DTRACE_HASHSTR(hash, template);
7654 int ndx = hashval & hash->dth_mask;
7655 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7656
7657 for (; bucket != NULL; bucket = bucket->dthb_next) {
7658 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
7659 return (bucket->dthb_chain);
7660 }
7661
7662 return (NULL);
7663 }
7664
7665 static int
7666 dtrace_hash_collisions(dtrace_hash_t *hash, dtrace_probe_t *template)
7667 {
7668 int hashval = DTRACE_HASHSTR(hash, template);
7669 int ndx = hashval & hash->dth_mask;
7670 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7671
7672 for (; bucket != NULL; bucket = bucket->dthb_next) {
7673 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
7674 return (bucket->dthb_len);
7675 }
7676
7677 return (0);
7678 }
7679
7680 static void
7681 dtrace_hash_remove(dtrace_hash_t *hash, dtrace_probe_t *probe)
7682 {
7683 int ndx = DTRACE_HASHSTR(hash, probe) & hash->dth_mask;
7684 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7685
7686 dtrace_probe_t **prevp = DTRACE_HASHPREV(hash, probe);
7687 dtrace_probe_t **nextp = DTRACE_HASHNEXT(hash, probe);
7688
7689 /*
7690 * Find the bucket that we're removing this probe from.
7691 */
7692 for (; bucket != NULL; bucket = bucket->dthb_next) {
7693 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, probe))
7694 break;
7695 }
7696
7697 ASSERT(bucket != NULL);
7698
7699 if (*prevp == NULL) {
7700 if (*nextp == NULL) {
7701 /*
7702 * The removed probe was the only probe on this
7703 * bucket; we need to remove the bucket.
7704 */
7705 dtrace_hashbucket_t *b = hash->dth_tab[ndx];
7706
7707 ASSERT(bucket->dthb_chain == probe);
7708 ASSERT(b != NULL);
7709
7710 if (b == bucket) {
7711 hash->dth_tab[ndx] = bucket->dthb_next;
7712 } else {
7713 while (b->dthb_next != bucket)
7714 b = b->dthb_next;
7715 b->dthb_next = bucket->dthb_next;
7716 }
7717
7718 ASSERT(hash->dth_nbuckets > 0);
7719 hash->dth_nbuckets--;
7720 kmem_free(bucket, sizeof (dtrace_hashbucket_t));
7721 return;
7722 }
7723
7724 bucket->dthb_chain = *nextp;
7725 } else {
7726 *(DTRACE_HASHNEXT(hash, *prevp)) = *nextp;
7727 }
7728
7729 if (*nextp != NULL)
7730 *(DTRACE_HASHPREV(hash, *nextp)) = *prevp;
7731 }
7732
7733 /*
7734 * DTrace Utility Functions
7735 *
7736 * These are random utility functions that are _not_ called from probe context.
7737 */
7738 static int
7739 dtrace_badattr(const dtrace_attribute_t *a)
7740 {
7741 return (a->dtat_name > DTRACE_STABILITY_MAX ||
7742 a->dtat_data > DTRACE_STABILITY_MAX ||
7743 a->dtat_class > DTRACE_CLASS_MAX);
7744 }
7745
7746 /*
7747 * Return a duplicate copy of a string. If the specified string is NULL,
7748 * this function returns a zero-length string.
7749 */
7750 static char *
7751 dtrace_strdup(const char *str)
7752 {
7753 char *new = kmem_zalloc((str != NULL ? strlen(str) : 0) + 1, KM_SLEEP);
7754
7755 if (str != NULL)
7756 (void) strcpy(new, str);
7757
7758 return (new);
7759 }
7760
7761 #define DTRACE_ISALPHA(c) \
7762 (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
7763
7764 static int
7765 dtrace_badname(const char *s)
7766 {
7767 char c;
7768
7769 if (s == NULL || (c = *s++) == '\0')
7770 return (0);
7771
7772 if (!DTRACE_ISALPHA(c) && c != '-' && c != '_' && c != '.')
7773 return (1);
7774
7775 while ((c = *s++) != '\0') {
7776 if (!DTRACE_ISALPHA(c) && (c < '0' || c > '9') &&
7777 c != '-' && c != '_' && c != '.' && c != '`')
7778 return (1);
7779 }
7780
7781 return (0);
7782 }
7783
7784 static void
7785 dtrace_cred2priv(cred_t *cr, uint32_t *privp, uid_t *uidp, zoneid_t *zoneidp)
7786 {
7787 uint32_t priv;
7788
7789 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
7790 /*
7791 * For DTRACE_PRIV_ALL, the uid and zoneid don't matter.
7792 */
7793 priv = DTRACE_PRIV_ALL;
7794 } else {
7795 *uidp = crgetuid(cr);
7796 *zoneidp = crgetzoneid(cr);
7797
7798 priv = 0;
7799 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE))
7800 priv |= DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER;
7801 else if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE))
7802 priv |= DTRACE_PRIV_USER;
7803 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE))
7804 priv |= DTRACE_PRIV_PROC;
7805 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
7806 priv |= DTRACE_PRIV_OWNER;
7807 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
7808 priv |= DTRACE_PRIV_ZONEOWNER;
7809 }
7810
7811 *privp = priv;
7812 }
7813
7814 #ifdef DTRACE_ERRDEBUG
7815 static void
7816 dtrace_errdebug(const char *str)
7817 {
7818 int hval = dtrace_hash_str((char *)str) % DTRACE_ERRHASHSZ;
7819 int occupied = 0;
7820
7821 mutex_enter(&dtrace_errlock);
7822 dtrace_errlast = str;
7823 dtrace_errthread = curthread;
7824
7825 while (occupied++ < DTRACE_ERRHASHSZ) {
7826 if (dtrace_errhash[hval].dter_msg == str) {
7827 dtrace_errhash[hval].dter_count++;
7828 goto out;
7829 }
7830
7831 if (dtrace_errhash[hval].dter_msg != NULL) {
7832 hval = (hval + 1) % DTRACE_ERRHASHSZ;
7833 continue;
7834 }
7835
7836 dtrace_errhash[hval].dter_msg = str;
7837 dtrace_errhash[hval].dter_count = 1;
7838 goto out;
7839 }
7840
7841 panic("dtrace: undersized error hash");
7842 out:
7843 mutex_exit(&dtrace_errlock);
7844 }
7845 #endif
7846
7847 /*
7848 * DTrace Matching Functions
7849 *
7850 * These functions are used to match groups of probes, given some elements of
7851 * a probe tuple, or some globbed expressions for elements of a probe tuple.
7852 */
7853 static int
7854 dtrace_match_priv(const dtrace_probe_t *prp, uint32_t priv, uid_t uid,
7855 zoneid_t zoneid)
7856 {
7857 if (priv != DTRACE_PRIV_ALL) {
7858 uint32_t ppriv = prp->dtpr_provider->dtpv_priv.dtpp_flags;
7859 uint32_t match = priv & ppriv;
7860
7861 /*
7862 * No PRIV_DTRACE_* privileges...
7863 */
7864 if ((priv & (DTRACE_PRIV_PROC | DTRACE_PRIV_USER |
7865 DTRACE_PRIV_KERNEL)) == 0)
7866 return (0);
7867
7868 /*
7869 * No matching bits, but there were bits to match...
7870 */
7871 if (match == 0 && ppriv != 0)
7872 return (0);
7873
7874 /*
7875 * Need to have permissions to the process, but don't...
7876 */
7877 if (((ppriv & ~match) & DTRACE_PRIV_OWNER) != 0 &&
7878 uid != prp->dtpr_provider->dtpv_priv.dtpp_uid) {
7879 return (0);
7880 }
7881
7882 /*
7883 * Need to be in the same zone unless we possess the
7884 * privilege to examine all zones.
7885 */
7886 if (((ppriv & ~match) & DTRACE_PRIV_ZONEOWNER) != 0 &&
7887 zoneid != prp->dtpr_provider->dtpv_priv.dtpp_zoneid) {
7888 return (0);
7889 }
7890 }
7891
7892 return (1);
7893 }
7894
7895 /*
7896 * dtrace_match_probe compares a dtrace_probe_t to a pre-compiled key, which
7897 * consists of input pattern strings and an ops-vector to evaluate them.
7898 * This function returns >0 for match, 0 for no match, and <0 for error.
7899 */
7900 static int
7901 dtrace_match_probe(const dtrace_probe_t *prp, const dtrace_probekey_t *pkp,
7902 uint32_t priv, uid_t uid, zoneid_t zoneid)
7903 {
7904 dtrace_provider_t *pvp = prp->dtpr_provider;
7905 int rv;
7906
7907 if (pvp->dtpv_defunct)
7908 return (0);
7909
7910 if ((rv = pkp->dtpk_pmatch(pvp->dtpv_name, pkp->dtpk_prov, 0)) <= 0)
7911 return (rv);
7912
7913 if ((rv = pkp->dtpk_mmatch(prp->dtpr_mod, pkp->dtpk_mod, 0)) <= 0)
7914 return (rv);
7915
7916 if ((rv = pkp->dtpk_fmatch(prp->dtpr_func, pkp->dtpk_func, 0)) <= 0)
7917 return (rv);
7918
7919 if ((rv = pkp->dtpk_nmatch(prp->dtpr_name, pkp->dtpk_name, 0)) <= 0)
7920 return (rv);
7921
7922 if (dtrace_match_priv(prp, priv, uid, zoneid) == 0)
7923 return (0);
7924
7925 return (rv);
7926 }
7927
7928 /*
7929 * dtrace_match_glob() is a safe kernel implementation of the gmatch(3GEN)
7930 * interface for matching a glob pattern 'p' to an input string 's'. Unlike
7931 * libc's version, the kernel version only applies to 8-bit ASCII strings.
7932 * In addition, all of the recursion cases except for '*' matching have been
7933 * unwound. For '*', we still implement recursive evaluation, but a depth
7934 * counter is maintained and matching is aborted if we recurse too deep.
7935 * The function returns 0 if no match, >0 if match, and <0 if recursion error.
7936 */
7937 static int
7938 dtrace_match_glob(const char *s, const char *p, int depth)
7939 {
7940 const char *olds;
7941 char s1, c;
7942 int gs;
7943
7944 if (depth > DTRACE_PROBEKEY_MAXDEPTH)
7945 return (-1);
7946
7947 if (s == NULL)
7948 s = ""; /* treat NULL as empty string */
7949
7950 top:
7951 olds = s;
7952 s1 = *s++;
7953
7954 if (p == NULL)
7955 return (0);
7956
7957 if ((c = *p++) == '\0')
7958 return (s1 == '\0');
7959
7960 switch (c) {
7961 case '[': {
7962 int ok = 0, notflag = 0;
7963 char lc = '\0';
7964
7965 if (s1 == '\0')
7966 return (0);
7967
7968 if (*p == '!') {
7969 notflag = 1;
7970 p++;
7971 }
7972
7973 if ((c = *p++) == '\0')
7974 return (0);
7975
7976 do {
7977 if (c == '-' && lc != '\0' && *p != ']') {
7978 if ((c = *p++) == '\0')
7979 return (0);
7980 if (c == '\\' && (c = *p++) == '\0')
7981 return (0);
7982
7983 if (notflag) {
7984 if (s1 < lc || s1 > c)
7985 ok++;
7986 else
7987 return (0);
7988 } else if (lc <= s1 && s1 <= c)
7989 ok++;
7990
7991 } else if (c == '\\' && (c = *p++) == '\0')
7992 return (0);
7993
7994 lc = c; /* save left-hand 'c' for next iteration */
7995
7996 if (notflag) {
7997 if (s1 != c)
7998 ok++;
7999 else
8000 return (0);
8001 } else if (s1 == c)
8002 ok++;
8003
8004 if ((c = *p++) == '\0')
8005 return (0);
8006
8007 } while (c != ']');
8008
8009 if (ok)
8010 goto top;
8011
8012 return (0);
8013 }
8014
8015 case '\\':
8016 if ((c = *p++) == '\0')
8017 return (0);
8018 /*FALLTHRU*/
8019
8020 default:
8021 if (c != s1)
8022 return (0);
8023 /*FALLTHRU*/
8024
8025 case '?':
8026 if (s1 != '\0')
8027 goto top;
8028 return (0);
8029
8030 case '*':
8031 while (*p == '*')
8032 p++; /* consecutive *'s are identical to a single one */
8033
8034 if (*p == '\0')
8035 return (1);
8036
8037 for (s = olds; *s != '\0'; s++) {
8038 if ((gs = dtrace_match_glob(s, p, depth + 1)) != 0)
8039 return (gs);
8040 }
8041
8042 return (0);
8043 }
8044 }
8045
8046 /*ARGSUSED*/
8047 static int
8048 dtrace_match_string(const char *s, const char *p, int depth)
8049 {
8050 return (s != NULL && strcmp(s, p) == 0);
8051 }
8052
8053 /*ARGSUSED*/
8054 static int
8055 dtrace_match_nul(const char *s, const char *p, int depth)
8056 {
8057 return (1); /* always match the empty pattern */
8058 }
8059
8060 /*ARGSUSED*/
8061 static int
8062 dtrace_match_nonzero(const char *s, const char *p, int depth)
8063 {
8064 return (s != NULL && s[0] != '\0');
8065 }
8066
8067 static int
8068 dtrace_match(const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid,
8069 zoneid_t zoneid, int (*matched)(dtrace_probe_t *, void *), void *arg)
8070 {
8071 dtrace_probe_t template, *probe;
8072 dtrace_hash_t *hash = NULL;
8073 int len, rc, best = INT_MAX, nmatched = 0;
8074 dtrace_id_t i;
8075
8076 ASSERT(MUTEX_HELD(&dtrace_lock));
8077
8078 /*
8079 * If the probe ID is specified in the key, just lookup by ID and
8080 * invoke the match callback once if a matching probe is found.
8081 */
8082 if (pkp->dtpk_id != DTRACE_IDNONE) {
8083 if ((probe = dtrace_probe_lookup_id(pkp->dtpk_id)) != NULL &&
8084 dtrace_match_probe(probe, pkp, priv, uid, zoneid) > 0) {
8085 if ((*matched)(probe, arg) == DTRACE_MATCH_FAIL)
8086 return (DTRACE_MATCH_FAIL);
8087 nmatched++;
8088 }
8089 return (nmatched);
8090 }
8091
8092 template.dtpr_mod = (char *)pkp->dtpk_mod;
8093 template.dtpr_func = (char *)pkp->dtpk_func;
8094 template.dtpr_name = (char *)pkp->dtpk_name;
8095
8096 /*
8097 * We want to find the most distinct of the module name, function
8098 * name, and name. So for each one that is not a glob pattern or
8099 * empty string, we perform a lookup in the corresponding hash and
8100 * use the hash table with the fewest collisions to do our search.
8101 */
8102 if (pkp->dtpk_mmatch == &dtrace_match_string &&
8103 (len = dtrace_hash_collisions(dtrace_bymod, &template)) < best) {
8104 best = len;
8105 hash = dtrace_bymod;
8106 }
8107
8108 if (pkp->dtpk_fmatch == &dtrace_match_string &&
8109 (len = dtrace_hash_collisions(dtrace_byfunc, &template)) < best) {
8110 best = len;
8111 hash = dtrace_byfunc;
8112 }
8113
8114 if (pkp->dtpk_nmatch == &dtrace_match_string &&
8115 (len = dtrace_hash_collisions(dtrace_byname, &template)) < best) {
8116 best = len;
8117 hash = dtrace_byname;
8118 }
8119
8120 /*
8121 * If we did not select a hash table, iterate over every probe and
8122 * invoke our callback for each one that matches our input probe key.
8123 */
8124 if (hash == NULL) {
8125 for (i = 0; i < dtrace_nprobes; i++) {
8126 if ((probe = dtrace_probes[i]) == NULL ||
8127 dtrace_match_probe(probe, pkp, priv, uid,
8128 zoneid) <= 0)
8129 continue;
8130
8131 nmatched++;
8132
8133 if ((rc = (*matched)(probe, arg)) !=
8134 DTRACE_MATCH_NEXT) {
8135 if (rc == DTRACE_MATCH_FAIL)
8136 return (DTRACE_MATCH_FAIL);
8137 break;
8138 }
8139 }
8140
8141 return (nmatched);
8142 }
8143
8144 /*
8145 * If we selected a hash table, iterate over each probe of the same key
8146 * name and invoke the callback for every probe that matches the other
8147 * attributes of our input probe key.
8148 */
8149 for (probe = dtrace_hash_lookup(hash, &template); probe != NULL;
8150 probe = *(DTRACE_HASHNEXT(hash, probe))) {
8151
8152 if (dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0)
8153 continue;
8154
8155 nmatched++;
8156
8157 if ((rc = (*matched)(probe, arg)) != DTRACE_MATCH_NEXT) {
8158 if (rc == DTRACE_MATCH_FAIL)
8159 return (DTRACE_MATCH_FAIL);
8160 break;
8161 }
8162 }
8163
8164 return (nmatched);
8165 }
8166
8167 /*
8168 * Return the function pointer dtrace_probecmp() should use to compare the
8169 * specified pattern with a string. For NULL or empty patterns, we select
8170 * dtrace_match_nul(). For glob pattern strings, we use dtrace_match_glob().
8171 * For non-empty non-glob strings, we use dtrace_match_string().
8172 */
8173 static dtrace_probekey_f *
8174 dtrace_probekey_func(const char *p)
8175 {
8176 char c;
8177
8178 if (p == NULL || *p == '\0')
8179 return (&dtrace_match_nul);
8180
8181 while ((c = *p++) != '\0') {
8182 if (c == '[' || c == '?' || c == '*' || c == '\\')
8183 return (&dtrace_match_glob);
8184 }
8185
8186 return (&dtrace_match_string);
8187 }
8188
8189 /*
8190 * Build a probe comparison key for use with dtrace_match_probe() from the
8191 * given probe description. By convention, a null key only matches anchored
8192 * probes: if each field is the empty string, reset dtpk_fmatch to
8193 * dtrace_match_nonzero().
8194 */
8195 static void
8196 dtrace_probekey(const dtrace_probedesc_t *pdp, dtrace_probekey_t *pkp)
8197 {
8198 pkp->dtpk_prov = pdp->dtpd_provider;
8199 pkp->dtpk_pmatch = dtrace_probekey_func(pdp->dtpd_provider);
8200
8201 pkp->dtpk_mod = pdp->dtpd_mod;
8202 pkp->dtpk_mmatch = dtrace_probekey_func(pdp->dtpd_mod);
8203
8204 pkp->dtpk_func = pdp->dtpd_func;
8205 pkp->dtpk_fmatch = dtrace_probekey_func(pdp->dtpd_func);
8206
8207 pkp->dtpk_name = pdp->dtpd_name;
8208 pkp->dtpk_nmatch = dtrace_probekey_func(pdp->dtpd_name);
8209
8210 pkp->dtpk_id = pdp->dtpd_id;
8211
8212 if (pkp->dtpk_id == DTRACE_IDNONE &&
8213 pkp->dtpk_pmatch == &dtrace_match_nul &&
8214 pkp->dtpk_mmatch == &dtrace_match_nul &&
8215 pkp->dtpk_fmatch == &dtrace_match_nul &&
8216 pkp->dtpk_nmatch == &dtrace_match_nul)
8217 pkp->dtpk_fmatch = &dtrace_match_nonzero;
8218 }
8219
8220 /*
8221 * DTrace Provider-to-Framework API Functions
8222 *
8223 * These functions implement much of the Provider-to-Framework API, as
8224 * described in <sys/dtrace.h>. The parts of the API not in this section are
8225 * the functions in the API for probe management (found below), and
8226 * dtrace_probe() itself (found above).
8227 */
8228
8229 /*
8230 * Register the calling provider with the DTrace framework. This should
8231 * generally be called by DTrace providers in their attach(9E) entry point.
8232 */
8233 int
8234 dtrace_register(const char *name, const dtrace_pattr_t *pap, uint32_t priv,
8235 cred_t *cr, const dtrace_pops_t *pops, void *arg, dtrace_provider_id_t *idp)
8236 {
8237 dtrace_provider_t *provider;
8238
8239 if (name == NULL || pap == NULL || pops == NULL || idp == NULL) {
8240 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8241 "arguments", name ? name : "<NULL>");
8242 return (EINVAL);
8243 }
8244
8245 if (name[0] == '\0' || dtrace_badname(name)) {
8246 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8247 "provider name", name);
8248 return (EINVAL);
8249 }
8250
8251 if ((pops->dtps_provide == NULL && pops->dtps_provide_module == NULL) ||
8252 pops->dtps_enable == NULL || pops->dtps_disable == NULL ||
8253 pops->dtps_destroy == NULL ||
8254 ((pops->dtps_resume == NULL) != (pops->dtps_suspend == NULL))) {
8255 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8256 "provider ops", name);
8257 return (EINVAL);
8258 }
8259
8260 if (dtrace_badattr(&pap->dtpa_provider) ||
8261 dtrace_badattr(&pap->dtpa_mod) ||
8262 dtrace_badattr(&pap->dtpa_func) ||
8263 dtrace_badattr(&pap->dtpa_name) ||
8264 dtrace_badattr(&pap->dtpa_args)) {
8265 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8266 "provider attributes", name);
8267 return (EINVAL);
8268 }
8269
8270 if (priv & ~DTRACE_PRIV_ALL) {
8271 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8272 "privilege attributes", name);
8273 return (EINVAL);
8274 }
8275
8276 if ((priv & DTRACE_PRIV_KERNEL) &&
8277 (priv & (DTRACE_PRIV_USER | DTRACE_PRIV_OWNER)) &&
8278 pops->dtps_mode == NULL) {
8279 cmn_err(CE_WARN, "failed to register provider '%s': need "
8280 "dtps_mode() op for given privilege attributes", name);
8281 return (EINVAL);
8282 }
8283
8284 provider = kmem_zalloc(sizeof (dtrace_provider_t), KM_SLEEP);
8285 provider->dtpv_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
8286 (void) strcpy(provider->dtpv_name, name);
8287
8288 provider->dtpv_attr = *pap;
8289 provider->dtpv_priv.dtpp_flags = priv;
8290 if (cr != NULL) {
8291 provider->dtpv_priv.dtpp_uid = crgetuid(cr);
8292 provider->dtpv_priv.dtpp_zoneid = crgetzoneid(cr);
8293 }
8294 provider->dtpv_pops = *pops;
8295
8296 if (pops->dtps_provide == NULL) {
8297 ASSERT(pops->dtps_provide_module != NULL);
8298 provider->dtpv_pops.dtps_provide = dtrace_nullop_provide;
8299 }
8300
8301 if (pops->dtps_provide_module == NULL) {
8302 ASSERT(pops->dtps_provide != NULL);
8303 provider->dtpv_pops.dtps_provide_module = dtrace_nullop_module;
8304 }
8305
8306 if (pops->dtps_suspend == NULL) {
8307 ASSERT(pops->dtps_resume == NULL);
8308 provider->dtpv_pops.dtps_suspend = dtrace_nullop;
8309 provider->dtpv_pops.dtps_resume = dtrace_nullop;
8310 }
8311
8312 provider->dtpv_arg = arg;
8313 *idp = (dtrace_provider_id_t)provider;
8314
8315 if (pops == &dtrace_provider_ops) {
8316 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
8317 ASSERT(MUTEX_HELD(&dtrace_lock));
8318 ASSERT(dtrace_anon.dta_enabling == NULL);
8319
8320 /*
8321 * We make sure that the DTrace provider is at the head of
8322 * the provider chain.
8323 */
8324 provider->dtpv_next = dtrace_provider;
8325 dtrace_provider = provider;
8326 return (0);
8327 }
8328
8329 mutex_enter(&dtrace_provider_lock);
8330 mutex_enter(&dtrace_lock);
8331
8332 /*
8333 * If there is at least one provider registered, we'll add this
8334 * provider after the first provider.
8335 */
8336 if (dtrace_provider != NULL) {
8337 provider->dtpv_next = dtrace_provider->dtpv_next;
8338 dtrace_provider->dtpv_next = provider;
8339 } else {
8340 dtrace_provider = provider;
8341 }
8342
8343 if (dtrace_retained != NULL) {
8344 dtrace_enabling_provide(provider);
8345
8346 /*
8347 * Now we need to call dtrace_enabling_matchall() -- which
8348 * will acquire cpu_lock and dtrace_lock. We therefore need
8349 * to drop all of our locks before calling into it...
8350 */
8351 mutex_exit(&dtrace_lock);
8352 mutex_exit(&dtrace_provider_lock);
8353 dtrace_enabling_matchall();
8354
8355 return (0);
8356 }
8357
8358 mutex_exit(&dtrace_lock);
8359 mutex_exit(&dtrace_provider_lock);
8360
8361 return (0);
8362 }
8363
8364 /*
8365 * Unregister the specified provider from the DTrace framework. This should
8366 * generally be called by DTrace providers in their detach(9E) entry point.
8367 */
8368 int
8369 dtrace_unregister(dtrace_provider_id_t id)
8370 {
8371 dtrace_provider_t *old = (dtrace_provider_t *)id;
8372 dtrace_provider_t *prev = NULL;
8373 int i, self = 0, noreap = 0;
8374 dtrace_probe_t *probe, *first = NULL;
8375
8376 if (old->dtpv_pops.dtps_enable == dtrace_enable_nullop) {
8377 /*
8378 * If DTrace itself is the provider, we're called with locks
8379 * already held.
8380 */
8381 ASSERT(old == dtrace_provider);
8382 ASSERT(dtrace_devi != NULL);
8383 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
8384 ASSERT(MUTEX_HELD(&dtrace_lock));
8385 self = 1;
8386
8387 if (dtrace_provider->dtpv_next != NULL) {
8388 /*
8389 * There's another provider here; return failure.
8390 */
8391 return (EBUSY);
8392 }
8393 } else {
8394 mutex_enter(&dtrace_provider_lock);
8395 mutex_enter(&mod_lock);
8396 mutex_enter(&dtrace_lock);
8397 }
8398
8399 /*
8400 * If anyone has /dev/dtrace open, or if there are anonymous enabled
8401 * probes, we refuse to let providers slither away, unless this
8402 * provider has already been explicitly invalidated.
8403 */
8404 if (!old->dtpv_defunct &&
8405 (dtrace_opens || (dtrace_anon.dta_state != NULL &&
8406 dtrace_anon.dta_state->dts_necbs > 0))) {
8407 if (!self) {
8408 mutex_exit(&dtrace_lock);
8409 mutex_exit(&mod_lock);
8410 mutex_exit(&dtrace_provider_lock);
8411 }
8412 return (EBUSY);
8413 }
8414
8415 /*
8416 * Attempt to destroy the probes associated with this provider.
8417 */
8418 for (i = 0; i < dtrace_nprobes; i++) {
8419 if ((probe = dtrace_probes[i]) == NULL)
8420 continue;
8421
8422 if (probe->dtpr_provider != old)
8423 continue;
8424
8425 if (probe->dtpr_ecb == NULL)
8426 continue;
8427
8428 /*
8429 * If we are trying to unregister a defunct provider, and the
8430 * provider was made defunct within the interval dictated by
8431 * dtrace_unregister_defunct_reap, we'll (asynchronously)
8432 * attempt to reap our enablings. To denote that the provider
8433 * should reattempt to unregister itself at some point in the
8434 * future, we will return a differentiable error code (EAGAIN
8435 * instead of EBUSY) in this case.
8436 */
8437 if (dtrace_gethrtime() - old->dtpv_defunct >
8438 dtrace_unregister_defunct_reap)
8439 noreap = 1;
8440
8441 if (!self) {
8442 mutex_exit(&dtrace_lock);
8443 mutex_exit(&mod_lock);
8444 mutex_exit(&dtrace_provider_lock);
8445 }
8446
8447 if (noreap)
8448 return (EBUSY);
8449
8450 (void) taskq_dispatch(dtrace_taskq,
8451 (task_func_t *)dtrace_enabling_reap, NULL, TQ_SLEEP);
8452
8453 return (EAGAIN);
8454 }
8455
8456 /*
8457 * All of the probes for this provider are disabled; we can safely
8458 * remove all of them from their hash chains and from the probe array.
8459 */
8460 for (i = 0; i < dtrace_nprobes; i++) {
8461 if ((probe = dtrace_probes[i]) == NULL)
8462 continue;
8463
8464 if (probe->dtpr_provider != old)
8465 continue;
8466
8467 dtrace_probes[i] = NULL;
8468
8469 dtrace_hash_remove(dtrace_bymod, probe);
8470 dtrace_hash_remove(dtrace_byfunc, probe);
8471 dtrace_hash_remove(dtrace_byname, probe);
8472
8473 if (first == NULL) {
8474 first = probe;
8475 probe->dtpr_nextmod = NULL;
8476 } else {
8477 probe->dtpr_nextmod = first;
8478 first = probe;
8479 }
8480 }
8481
8482 /*
8483 * The provider's probes have been removed from the hash chains and
8484 * from the probe array. Now issue a dtrace_sync() to be sure that
8485 * everyone has cleared out from any probe array processing.
8486 */
8487 dtrace_sync();
8488
8489 for (probe = first; probe != NULL; probe = first) {
8490 first = probe->dtpr_nextmod;
8491
8492 old->dtpv_pops.dtps_destroy(old->dtpv_arg, probe->dtpr_id,
8493 probe->dtpr_arg);
8494 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
8495 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
8496 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
8497 vmem_free(dtrace_arena, (void *)(uintptr_t)(probe->dtpr_id), 1);
8498 kmem_free(probe, sizeof (dtrace_probe_t));
8499 }
8500
8501 if ((prev = dtrace_provider) == old) {
8502 ASSERT(self || dtrace_devi == NULL);
8503 ASSERT(old->dtpv_next == NULL || dtrace_devi == NULL);
8504 dtrace_provider = old->dtpv_next;
8505 } else {
8506 while (prev != NULL && prev->dtpv_next != old)
8507 prev = prev->dtpv_next;
8508
8509 if (prev == NULL) {
8510 panic("attempt to unregister non-existent "
8511 "dtrace provider %p\n", (void *)id);
8512 }
8513
8514 prev->dtpv_next = old->dtpv_next;
8515 }
8516
8517 if (!self) {
8518 mutex_exit(&dtrace_lock);
8519 mutex_exit(&mod_lock);
8520 mutex_exit(&dtrace_provider_lock);
8521 }
8522
8523 kmem_free(old->dtpv_name, strlen(old->dtpv_name) + 1);
8524 kmem_free(old, sizeof (dtrace_provider_t));
8525
8526 return (0);
8527 }
8528
8529 /*
8530 * Invalidate the specified provider. All subsequent probe lookups for the
8531 * specified provider will fail, but its probes will not be removed.
8532 */
8533 void
8534 dtrace_invalidate(dtrace_provider_id_t id)
8535 {
8536 dtrace_provider_t *pvp = (dtrace_provider_t *)id;
8537
8538 ASSERT(pvp->dtpv_pops.dtps_enable != dtrace_enable_nullop);
8539
8540 mutex_enter(&dtrace_provider_lock);
8541 mutex_enter(&dtrace_lock);
8542
8543 pvp->dtpv_defunct = dtrace_gethrtime();
8544
8545 mutex_exit(&dtrace_lock);
8546 mutex_exit(&dtrace_provider_lock);
8547 }
8548
8549 /*
8550 * Indicate whether or not DTrace has attached.
8551 */
8552 int
8553 dtrace_attached(void)
8554 {
8555 /*
8556 * dtrace_provider will be non-NULL iff the DTrace driver has
8557 * attached. (It's non-NULL because DTrace is always itself a
8558 * provider.)
8559 */
8560 return (dtrace_provider != NULL);
8561 }
8562
8563 /*
8564 * Remove all the unenabled probes for the given provider. This function is
8565 * not unlike dtrace_unregister(), except that it doesn't remove the provider
8566 * -- just as many of its associated probes as it can.
8567 */
8568 int
8569 dtrace_condense(dtrace_provider_id_t id)
8570 {
8571 dtrace_provider_t *prov = (dtrace_provider_t *)id;
8572 int i;
8573 dtrace_probe_t *probe;
8574
8575 /*
8576 * Make sure this isn't the dtrace provider itself.
8577 */
8578 ASSERT(prov->dtpv_pops.dtps_enable != dtrace_enable_nullop);
8579
8580 mutex_enter(&dtrace_provider_lock);
8581 mutex_enter(&dtrace_lock);
8582
8583 /*
8584 * Attempt to destroy the probes associated with this provider.
8585 */
8586 for (i = 0; i < dtrace_nprobes; i++) {
8587 if ((probe = dtrace_probes[i]) == NULL)
8588 continue;
8589
8590 if (probe->dtpr_provider != prov)
8591 continue;
8592
8593 if (probe->dtpr_ecb != NULL)
8594 continue;
8595
8596 dtrace_probes[i] = NULL;
8597
8598 dtrace_hash_remove(dtrace_bymod, probe);
8599 dtrace_hash_remove(dtrace_byfunc, probe);
8600 dtrace_hash_remove(dtrace_byname, probe);
8601
8602 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, i + 1,
8603 probe->dtpr_arg);
8604 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
8605 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
8606 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
8607 kmem_free(probe, sizeof (dtrace_probe_t));
8608 vmem_free(dtrace_arena, (void *)((uintptr_t)i + 1), 1);
8609 }
8610
8611 mutex_exit(&dtrace_lock);
8612 mutex_exit(&dtrace_provider_lock);
8613
8614 return (0);
8615 }
8616
8617 /*
8618 * DTrace Probe Management Functions
8619 *
8620 * The functions in this section perform the DTrace probe management,
8621 * including functions to create probes, look-up probes, and call into the
8622 * providers to request that probes be provided. Some of these functions are
8623 * in the Provider-to-Framework API; these functions can be identified by the
8624 * fact that they are not declared "static".
8625 */
8626
8627 /*
8628 * Create a probe with the specified module name, function name, and name.
8629 */
8630 dtrace_id_t
8631 dtrace_probe_create(dtrace_provider_id_t prov, const char *mod,
8632 const char *func, const char *name, int aframes, void *arg)
8633 {
8634 dtrace_probe_t *probe, **probes;
8635 dtrace_provider_t *provider = (dtrace_provider_t *)prov;
8636 dtrace_id_t id;
8637
8638 if (provider == dtrace_provider) {
8639 ASSERT(MUTEX_HELD(&dtrace_lock));
8640 } else {
8641 mutex_enter(&dtrace_lock);
8642 }
8643
8644 id = (dtrace_id_t)(uintptr_t)vmem_alloc(dtrace_arena, 1,
8645 VM_BESTFIT | VM_SLEEP);
8646 probe = kmem_zalloc(sizeof (dtrace_probe_t), KM_SLEEP);
8647
8648 probe->dtpr_id = id;
8649 probe->dtpr_gen = dtrace_probegen++;
8650 probe->dtpr_mod = dtrace_strdup(mod);
8651 probe->dtpr_func = dtrace_strdup(func);
8652 probe->dtpr_name = dtrace_strdup(name);
8653 probe->dtpr_arg = arg;
8654 probe->dtpr_aframes = aframes;
8655 probe->dtpr_provider = provider;
8656
8657 dtrace_hash_add(dtrace_bymod, probe);
8658 dtrace_hash_add(dtrace_byfunc, probe);
8659 dtrace_hash_add(dtrace_byname, probe);
8660
8661 if (id - 1 >= dtrace_nprobes) {
8662 size_t osize = dtrace_nprobes * sizeof (dtrace_probe_t *);
8663 size_t nsize = osize << 1;
8664
8665 if (nsize == 0) {
8666 ASSERT(osize == 0);
8667 ASSERT(dtrace_probes == NULL);
8668 nsize = sizeof (dtrace_probe_t *);
8669 }
8670
8671 probes = kmem_zalloc(nsize, KM_SLEEP);
8672
8673 if (dtrace_probes == NULL) {
8674 ASSERT(osize == 0);
8675 dtrace_probes = probes;
8676 dtrace_nprobes = 1;
8677 } else {
8678 dtrace_probe_t **oprobes = dtrace_probes;
8679
8680 bcopy(oprobes, probes, osize);
8681 dtrace_membar_producer();
8682 dtrace_probes = probes;
8683
8684 dtrace_sync();
8685
8686 /*
8687 * All CPUs are now seeing the new probes array; we can
8688 * safely free the old array.
8689 */
8690 kmem_free(oprobes, osize);
8691 dtrace_nprobes <<= 1;
8692 }
8693
8694 ASSERT(id - 1 < dtrace_nprobes);
8695 }
8696
8697 ASSERT(dtrace_probes[id - 1] == NULL);
8698 dtrace_probes[id - 1] = probe;
8699
8700 if (provider != dtrace_provider)
8701 mutex_exit(&dtrace_lock);
8702
8703 return (id);
8704 }
8705
8706 static dtrace_probe_t *
8707 dtrace_probe_lookup_id(dtrace_id_t id)
8708 {
8709 ASSERT(MUTEX_HELD(&dtrace_lock));
8710
8711 if (id == 0 || id > dtrace_nprobes)
8712 return (NULL);
8713
8714 return (dtrace_probes[id - 1]);
8715 }
8716
8717 static int
8718 dtrace_probe_lookup_match(dtrace_probe_t *probe, void *arg)
8719 {
8720 *((dtrace_id_t *)arg) = probe->dtpr_id;
8721
8722 return (DTRACE_MATCH_DONE);
8723 }
8724
8725 /*
8726 * Look up a probe based on provider and one or more of module name, function
8727 * name and probe name.
8728 */
8729 dtrace_id_t
8730 dtrace_probe_lookup(dtrace_provider_id_t prid, const char *mod,
8731 const char *func, const char *name)
8732 {
8733 dtrace_probekey_t pkey;
8734 dtrace_id_t id;
8735 int match;
8736
8737 pkey.dtpk_prov = ((dtrace_provider_t *)prid)->dtpv_name;
8738 pkey.dtpk_pmatch = &dtrace_match_string;
8739 pkey.dtpk_mod = mod;
8740 pkey.dtpk_mmatch = mod ? &dtrace_match_string : &dtrace_match_nul;
8741 pkey.dtpk_func = func;
8742 pkey.dtpk_fmatch = func ? &dtrace_match_string : &dtrace_match_nul;
8743 pkey.dtpk_name = name;
8744 pkey.dtpk_nmatch = name ? &dtrace_match_string : &dtrace_match_nul;
8745 pkey.dtpk_id = DTRACE_IDNONE;
8746
8747 mutex_enter(&dtrace_lock);
8748 match = dtrace_match(&pkey, DTRACE_PRIV_ALL, 0, 0,
8749 dtrace_probe_lookup_match, &id);
8750 mutex_exit(&dtrace_lock);
8751
8752 ASSERT(match == 1 || match == 0);
8753 return (match ? id : 0);
8754 }
8755
8756 /*
8757 * Returns the probe argument associated with the specified probe.
8758 */
8759 void *
8760 dtrace_probe_arg(dtrace_provider_id_t id, dtrace_id_t pid)
8761 {
8762 dtrace_probe_t *probe;
8763 void *rval = NULL;
8764
8765 mutex_enter(&dtrace_lock);
8766
8767 if ((probe = dtrace_probe_lookup_id(pid)) != NULL &&
8768 probe->dtpr_provider == (dtrace_provider_t *)id)
8769 rval = probe->dtpr_arg;
8770
8771 mutex_exit(&dtrace_lock);
8772
8773 return (rval);
8774 }
8775
8776 /*
8777 * Copy a probe into a probe description.
8778 */
8779 static void
8780 dtrace_probe_description(const dtrace_probe_t *prp, dtrace_probedesc_t *pdp)
8781 {
8782 bzero(pdp, sizeof (dtrace_probedesc_t));
8783 pdp->dtpd_id = prp->dtpr_id;
8784
8785 (void) strncpy(pdp->dtpd_provider,
8786 prp->dtpr_provider->dtpv_name, DTRACE_PROVNAMELEN - 1);
8787
8788 (void) strncpy(pdp->dtpd_mod, prp->dtpr_mod, DTRACE_MODNAMELEN - 1);
8789 (void) strncpy(pdp->dtpd_func, prp->dtpr_func, DTRACE_FUNCNAMELEN - 1);
8790 (void) strncpy(pdp->dtpd_name, prp->dtpr_name, DTRACE_NAMELEN - 1);
8791 }
8792
8793 /*
8794 * Called to indicate that a probe -- or probes -- should be provided by a
8795 * specfied provider. If the specified description is NULL, the provider will
8796 * be told to provide all of its probes. (This is done whenever a new
8797 * consumer comes along, or whenever a retained enabling is to be matched.) If
8798 * the specified description is non-NULL, the provider is given the
8799 * opportunity to dynamically provide the specified probe, allowing providers
8800 * to support the creation of probes on-the-fly. (So-called _autocreated_
8801 * probes.) If the provider is NULL, the operations will be applied to all
8802 * providers; if the provider is non-NULL the operations will only be applied
8803 * to the specified provider. The dtrace_provider_lock must be held, and the
8804 * dtrace_lock must _not_ be held -- the provider's dtps_provide() operation
8805 * will need to grab the dtrace_lock when it reenters the framework through
8806 * dtrace_probe_lookup(), dtrace_probe_create(), etc.
8807 */
8808 static void
8809 dtrace_probe_provide(dtrace_probedesc_t *desc, dtrace_provider_t *prv)
8810 {
8811 struct modctl *ctl;
8812 int all = 0;
8813
8814 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
8815
8816 if (prv == NULL) {
8817 all = 1;
8818 prv = dtrace_provider;
8819 }
8820
8821 do {
8822 /*
8823 * First, call the blanket provide operation.
8824 */
8825 prv->dtpv_pops.dtps_provide(prv->dtpv_arg, desc);
8826
8827 /*
8828 * Now call the per-module provide operation. We will grab
8829 * mod_lock to prevent the list from being modified. Note
8830 * that this also prevents the mod_busy bits from changing.
8831 * (mod_busy can only be changed with mod_lock held.)
8832 */
8833 mutex_enter(&mod_lock);
8834
8835 ctl = &modules;
8836 do {
8837 if (ctl->mod_busy || ctl->mod_mp == NULL)
8838 continue;
8839
8840 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
8841
8842 } while ((ctl = ctl->mod_next) != &modules);
8843
8844 mutex_exit(&mod_lock);
8845 } while (all && (prv = prv->dtpv_next) != NULL);
8846 }
8847
8848 /*
8849 * Iterate over each probe, and call the Framework-to-Provider API function
8850 * denoted by offs.
8851 */
8852 static void
8853 dtrace_probe_foreach(uintptr_t offs)
8854 {
8855 dtrace_provider_t *prov;
8856 void (*func)(void *, dtrace_id_t, void *);
8857 dtrace_probe_t *probe;
8858 dtrace_icookie_t cookie;
8859 int i;
8860
8861 /*
8862 * We disable interrupts to walk through the probe array. This is
8863 * safe -- the dtrace_sync() in dtrace_unregister() assures that we
8864 * won't see stale data.
8865 */
8866 cookie = dtrace_interrupt_disable();
8867
8868 for (i = 0; i < dtrace_nprobes; i++) {
8869 if ((probe = dtrace_probes[i]) == NULL)
8870 continue;
8871
8872 if (probe->dtpr_ecb == NULL) {
8873 /*
8874 * This probe isn't enabled -- don't call the function.
8875 */
8876 continue;
8877 }
8878
8879 prov = probe->dtpr_provider;
8880 func = *((void(**)(void *, dtrace_id_t, void *))
8881 ((uintptr_t)&prov->dtpv_pops + offs));
8882
8883 func(prov->dtpv_arg, i + 1, probe->dtpr_arg);
8884 }
8885
8886 dtrace_interrupt_enable(cookie);
8887 }
8888
8889 static int
8890 dtrace_probe_enable(const dtrace_probedesc_t *desc, dtrace_enabling_t *enab)
8891 {
8892 dtrace_probekey_t pkey;
8893 uint32_t priv;
8894 uid_t uid;
8895 zoneid_t zoneid;
8896
8897 ASSERT(MUTEX_HELD(&dtrace_lock));
8898 dtrace_ecb_create_cache = NULL;
8899
8900 if (desc == NULL) {
8901 /*
8902 * If we're passed a NULL description, we're being asked to
8903 * create an ECB with a NULL probe.
8904 */
8905 (void) dtrace_ecb_create_enable(NULL, enab);
8906 return (0);
8907 }
8908
8909 dtrace_probekey(desc, &pkey);
8910 dtrace_cred2priv(enab->dten_vstate->dtvs_state->dts_cred.dcr_cred,
8911 &priv, &uid, &zoneid);
8912
8913 return (dtrace_match(&pkey, priv, uid, zoneid, dtrace_ecb_create_enable,
8914 enab));
8915 }
8916
8917 /*
8918 * DTrace Helper Provider Functions
8919 */
8920 static void
8921 dtrace_dofattr2attr(dtrace_attribute_t *attr, const dof_attr_t dofattr)
8922 {
8923 attr->dtat_name = DOF_ATTR_NAME(dofattr);
8924 attr->dtat_data = DOF_ATTR_DATA(dofattr);
8925 attr->dtat_class = DOF_ATTR_CLASS(dofattr);
8926 }
8927
8928 static void
8929 dtrace_dofprov2hprov(dtrace_helper_provdesc_t *hprov,
8930 const dof_provider_t *dofprov, char *strtab)
8931 {
8932 hprov->dthpv_provname = strtab + dofprov->dofpv_name;
8933 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_provider,
8934 dofprov->dofpv_provattr);
8935 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_mod,
8936 dofprov->dofpv_modattr);
8937 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_func,
8938 dofprov->dofpv_funcattr);
8939 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_name,
8940 dofprov->dofpv_nameattr);
8941 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_args,
8942 dofprov->dofpv_argsattr);
8943 }
8944
8945 static void
8946 dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
8947 {
8948 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
8949 dof_hdr_t *dof = (dof_hdr_t *)daddr;
8950 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
8951 dof_provider_t *provider;
8952 dof_probe_t *probe;
8953 uint32_t *off, *enoff;
8954 uint8_t *arg;
8955 char *strtab;
8956 uint_t i, nprobes;
8957 dtrace_helper_provdesc_t dhpv;
8958 dtrace_helper_probedesc_t dhpb;
8959 dtrace_meta_t *meta = dtrace_meta_pid;
8960 dtrace_mops_t *mops = &meta->dtm_mops;
8961 void *parg;
8962
8963 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
8964 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8965 provider->dofpv_strtab * dof->dofh_secsize);
8966 prb_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8967 provider->dofpv_probes * dof->dofh_secsize);
8968 arg_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8969 provider->dofpv_prargs * dof->dofh_secsize);
8970 off_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8971 provider->dofpv_proffs * dof->dofh_secsize);
8972
8973 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
8974 off = (uint32_t *)(uintptr_t)(daddr + off_sec->dofs_offset);
8975 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
8976 enoff = NULL;
8977
8978 /*
8979 * See dtrace_helper_provider_validate().
8980 */
8981 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
8982 provider->dofpv_prenoffs != DOF_SECT_NONE) {
8983 enoff_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8984 provider->dofpv_prenoffs * dof->dofh_secsize);
8985 enoff = (uint32_t *)(uintptr_t)(daddr + enoff_sec->dofs_offset);
8986 }
8987
8988 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
8989
8990 /*
8991 * Create the provider.
8992 */
8993 dtrace_dofprov2hprov(&dhpv, provider, strtab);
8994
8995 if ((parg = mops->dtms_provide_pid(meta->dtm_arg, &dhpv, pid)) == NULL)
8996 return;
8997
8998 meta->dtm_count++;
8999
9000 /*
9001 * Create the probes.
9002 */
9003 for (i = 0; i < nprobes; i++) {
9004 probe = (dof_probe_t *)(uintptr_t)(daddr +
9005 prb_sec->dofs_offset + i * prb_sec->dofs_entsize);
9006
9007 dhpb.dthpb_mod = dhp->dofhp_mod;
9008 dhpb.dthpb_func = strtab + probe->dofpr_func;
9009 dhpb.dthpb_name = strtab + probe->dofpr_name;
9010 dhpb.dthpb_base = probe->dofpr_addr;
9011 dhpb.dthpb_offs = off + probe->dofpr_offidx;
9012 dhpb.dthpb_noffs = probe->dofpr_noffs;
9013 if (enoff != NULL) {
9014 dhpb.dthpb_enoffs = enoff + probe->dofpr_enoffidx;
9015 dhpb.dthpb_nenoffs = probe->dofpr_nenoffs;
9016 } else {
9017 dhpb.dthpb_enoffs = NULL;
9018 dhpb.dthpb_nenoffs = 0;
9019 }
9020 dhpb.dthpb_args = arg + probe->dofpr_argidx;
9021 dhpb.dthpb_nargc = probe->dofpr_nargc;
9022 dhpb.dthpb_xargc = probe->dofpr_xargc;
9023 dhpb.dthpb_ntypes = strtab + probe->dofpr_nargv;
9024 dhpb.dthpb_xtypes = strtab + probe->dofpr_xargv;
9025
9026 mops->dtms_create_probe(meta->dtm_arg, parg, &dhpb);
9027 }
9028 }
9029
9030 static void
9031 dtrace_helper_provide(dof_helper_t *dhp, pid_t pid)
9032 {
9033 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
9034 dof_hdr_t *dof = (dof_hdr_t *)daddr;
9035 int i;
9036
9037 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
9038
9039 for (i = 0; i < dof->dofh_secnum; i++) {
9040 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
9041 dof->dofh_secoff + i * dof->dofh_secsize);
9042
9043 if (sec->dofs_type != DOF_SECT_PROVIDER)
9044 continue;
9045
9046 dtrace_helper_provide_one(dhp, sec, pid);
9047 }
9048
9049 /*
9050 * We may have just created probes, so we must now rematch against
9051 * any retained enablings. Note that this call will acquire both
9052 * cpu_lock and dtrace_lock; the fact that we are holding
9053 * dtrace_meta_lock now is what defines the ordering with respect to
9054 * these three locks.
9055 */
9056 dtrace_enabling_matchall();
9057 }
9058
9059 static void
9060 dtrace_helper_provider_remove_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
9061 {
9062 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
9063 dof_hdr_t *dof = (dof_hdr_t *)daddr;
9064 dof_sec_t *str_sec;
9065 dof_provider_t *provider;
9066 char *strtab;
9067 dtrace_helper_provdesc_t dhpv;
9068 dtrace_meta_t *meta = dtrace_meta_pid;
9069 dtrace_mops_t *mops = &meta->dtm_mops;
9070
9071 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
9072 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
9073 provider->dofpv_strtab * dof->dofh_secsize);
9074
9075 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
9076
9077 /*
9078 * Create the provider.
9079 */
9080 dtrace_dofprov2hprov(&dhpv, provider, strtab);
9081
9082 mops->dtms_remove_pid(meta->dtm_arg, &dhpv, pid);
9083
9084 meta->dtm_count--;
9085 }
9086
9087 static void
9088 dtrace_helper_provider_remove(dof_helper_t *dhp, pid_t pid)
9089 {
9090 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
9091 dof_hdr_t *dof = (dof_hdr_t *)daddr;
9092 int i;
9093
9094 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
9095
9096 for (i = 0; i < dof->dofh_secnum; i++) {
9097 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
9098 dof->dofh_secoff + i * dof->dofh_secsize);
9099
9100 if (sec->dofs_type != DOF_SECT_PROVIDER)
9101 continue;
9102
9103 dtrace_helper_provider_remove_one(dhp, sec, pid);
9104 }
9105 }
9106
9107 /*
9108 * DTrace Meta Provider-to-Framework API Functions
9109 *
9110 * These functions implement the Meta Provider-to-Framework API, as described
9111 * in <sys/dtrace.h>.
9112 */
9113 int
9114 dtrace_meta_register(const char *name, const dtrace_mops_t *mops, void *arg,
9115 dtrace_meta_provider_id_t *idp)
9116 {
9117 dtrace_meta_t *meta;
9118 dtrace_helpers_t *help, *next;
9119 int i;
9120
9121 *idp = DTRACE_METAPROVNONE;
9122
9123 /*
9124 * We strictly don't need the name, but we hold onto it for
9125 * debuggability. All hail error queues!
9126 */
9127 if (name == NULL) {
9128 cmn_err(CE_WARN, "failed to register meta-provider: "
9129 "invalid name");
9130 return (EINVAL);
9131 }
9132
9133 if (mops == NULL ||
9134 mops->dtms_create_probe == NULL ||
9135 mops->dtms_provide_pid == NULL ||
9136 mops->dtms_remove_pid == NULL) {
9137 cmn_err(CE_WARN, "failed to register meta-register %s: "
9138 "invalid ops", name);
9139 return (EINVAL);
9140 }
9141
9142 meta = kmem_zalloc(sizeof (dtrace_meta_t), KM_SLEEP);
9143 meta->dtm_mops = *mops;
9144 meta->dtm_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
9145 (void) strcpy(meta->dtm_name, name);
9146 meta->dtm_arg = arg;
9147
9148 mutex_enter(&dtrace_meta_lock);
9149 mutex_enter(&dtrace_lock);
9150
9151 if (dtrace_meta_pid != NULL) {
9152 mutex_exit(&dtrace_lock);
9153 mutex_exit(&dtrace_meta_lock);
9154 cmn_err(CE_WARN, "failed to register meta-register %s: "
9155 "user-land meta-provider exists", name);
9156 kmem_free(meta->dtm_name, strlen(meta->dtm_name) + 1);
9157 kmem_free(meta, sizeof (dtrace_meta_t));
9158 return (EINVAL);
9159 }
9160
9161 dtrace_meta_pid = meta;
9162 *idp = (dtrace_meta_provider_id_t)meta;
9163
9164 /*
9165 * If there are providers and probes ready to go, pass them
9166 * off to the new meta provider now.
9167 */
9168
9169 help = dtrace_deferred_pid;
9170 dtrace_deferred_pid = NULL;
9171
9172 mutex_exit(&dtrace_lock);
9173
9174 while (help != NULL) {
9175 for (i = 0; i < help->dthps_nprovs; i++) {
9176 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
9177 help->dthps_pid);
9178 }
9179
9180 next = help->dthps_next;
9181 help->dthps_next = NULL;
9182 help->dthps_prev = NULL;
9183 help->dthps_deferred = 0;
9184 help = next;
9185 }
9186
9187 mutex_exit(&dtrace_meta_lock);
9188
9189 return (0);
9190 }
9191
9192 int
9193 dtrace_meta_unregister(dtrace_meta_provider_id_t id)
9194 {
9195 dtrace_meta_t **pp, *old = (dtrace_meta_t *)id;
9196
9197 mutex_enter(&dtrace_meta_lock);
9198 mutex_enter(&dtrace_lock);
9199
9200 if (old == dtrace_meta_pid) {
9201 pp = &dtrace_meta_pid;
9202 } else {
9203 panic("attempt to unregister non-existent "
9204 "dtrace meta-provider %p\n", (void *)old);
9205 }
9206
9207 if (old->dtm_count != 0) {
9208 mutex_exit(&dtrace_lock);
9209 mutex_exit(&dtrace_meta_lock);
9210 return (EBUSY);
9211 }
9212
9213 *pp = NULL;
9214
9215 mutex_exit(&dtrace_lock);
9216 mutex_exit(&dtrace_meta_lock);
9217
9218 kmem_free(old->dtm_name, strlen(old->dtm_name) + 1);
9219 kmem_free(old, sizeof (dtrace_meta_t));
9220
9221 return (0);
9222 }
9223
9224
9225 /*
9226 * DTrace DIF Object Functions
9227 */
9228 static int
9229 dtrace_difo_err(uint_t pc, const char *format, ...)
9230 {
9231 if (dtrace_err_verbose) {
9232 va_list alist;
9233
9234 (void) uprintf("dtrace DIF object error: [%u]: ", pc);
9235 va_start(alist, format);
9236 (void) vuprintf(format, alist);
9237 va_end(alist);
9238 }
9239
9240 #ifdef DTRACE_ERRDEBUG
9241 dtrace_errdebug(format);
9242 #endif
9243 return (1);
9244 }
9245
9246 /*
9247 * Validate a DTrace DIF object by checking the IR instructions. The following
9248 * rules are currently enforced by dtrace_difo_validate():
9249 *
9250 * 1. Each instruction must have a valid opcode
9251 * 2. Each register, string, variable, or subroutine reference must be valid
9252 * 3. No instruction can modify register %r0 (must be zero)
9253 * 4. All instruction reserved bits must be set to zero
9254 * 5. The last instruction must be a "ret" instruction
9255 * 6. All branch targets must reference a valid instruction _after_ the branch
9256 */
9257 static int
9258 dtrace_difo_validate(dtrace_difo_t *dp, dtrace_vstate_t *vstate, uint_t nregs,
9259 cred_t *cr)
9260 {
9261 int err = 0, i;
9262 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
9263 int kcheckload;
9264 uint_t pc;
9265 int maxglobal = -1, maxlocal = -1, maxtlocal = -1;
9266
9267 kcheckload = cr == NULL ||
9268 (vstate->dtvs_state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) == 0;
9269
9270 dp->dtdo_destructive = 0;
9271
9272 for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) {
9273 dif_instr_t instr = dp->dtdo_buf[pc];
9274
9275 uint_t r1 = DIF_INSTR_R1(instr);
9276 uint_t r2 = DIF_INSTR_R2(instr);
9277 uint_t rd = DIF_INSTR_RD(instr);
9278 uint_t rs = DIF_INSTR_RS(instr);
9279 uint_t label = DIF_INSTR_LABEL(instr);
9280 uint_t v = DIF_INSTR_VAR(instr);
9281 uint_t subr = DIF_INSTR_SUBR(instr);
9282 uint_t type = DIF_INSTR_TYPE(instr);
9283 uint_t op = DIF_INSTR_OP(instr);
9284
9285 switch (op) {
9286 case DIF_OP_OR:
9287 case DIF_OP_XOR:
9288 case DIF_OP_AND:
9289 case DIF_OP_SLL:
9290 case DIF_OP_SRL:
9291 case DIF_OP_SRA:
9292 case DIF_OP_SUB:
9293 case DIF_OP_ADD:
9294 case DIF_OP_MUL:
9295 case DIF_OP_SDIV:
9296 case DIF_OP_UDIV:
9297 case DIF_OP_SREM:
9298 case DIF_OP_UREM:
9299 case DIF_OP_COPYS:
9300 if (r1 >= nregs)
9301 err += efunc(pc, "invalid register %u\n", r1);
9302 if (r2 >= nregs)
9303 err += efunc(pc, "invalid register %u\n", r2);
9304 if (rd >= nregs)
9305 err += efunc(pc, "invalid register %u\n", rd);
9306 if (rd == 0)
9307 err += efunc(pc, "cannot write to %r0\n");
9308 break;
9309 case DIF_OP_NOT:
9310 case DIF_OP_MOV:
9311 case DIF_OP_ALLOCS:
9312 if (r1 >= nregs)
9313 err += efunc(pc, "invalid register %u\n", r1);
9314 if (r2 != 0)
9315 err += efunc(pc, "non-zero reserved bits\n");
9316 if (rd >= nregs)
9317 err += efunc(pc, "invalid register %u\n", rd);
9318 if (rd == 0)
9319 err += efunc(pc, "cannot write to %r0\n");
9320 break;
9321 case DIF_OP_LDSB:
9322 case DIF_OP_LDSH:
9323 case DIF_OP_LDSW:
9324 case DIF_OP_LDUB:
9325 case DIF_OP_LDUH:
9326 case DIF_OP_LDUW:
9327 case DIF_OP_LDX:
9328 if (r1 >= nregs)
9329 err += efunc(pc, "invalid register %u\n", r1);
9330 if (r2 != 0)
9331 err += efunc(pc, "non-zero reserved bits\n");
9332 if (rd >= nregs)
9333 err += efunc(pc, "invalid register %u\n", rd);
9334 if (rd == 0)
9335 err += efunc(pc, "cannot write to %r0\n");
9336 if (kcheckload)
9337 dp->dtdo_buf[pc] = DIF_INSTR_LOAD(op +
9338 DIF_OP_RLDSB - DIF_OP_LDSB, r1, rd);
9339 break;
9340 case DIF_OP_RLDSB:
9341 case DIF_OP_RLDSH:
9342 case DIF_OP_RLDSW:
9343 case DIF_OP_RLDUB:
9344 case DIF_OP_RLDUH:
9345 case DIF_OP_RLDUW:
9346 case DIF_OP_RLDX:
9347 if (r1 >= nregs)
9348 err += efunc(pc, "invalid register %u\n", r1);
9349 if (r2 != 0)
9350 err += efunc(pc, "non-zero reserved bits\n");
9351 if (rd >= nregs)
9352 err += efunc(pc, "invalid register %u\n", rd);
9353 if (rd == 0)
9354 err += efunc(pc, "cannot write to %r0\n");
9355 break;
9356 case DIF_OP_ULDSB:
9357 case DIF_OP_ULDSH:
9358 case DIF_OP_ULDSW:
9359 case DIF_OP_ULDUB:
9360 case DIF_OP_ULDUH:
9361 case DIF_OP_ULDUW:
9362 case DIF_OP_ULDX:
9363 if (r1 >= nregs)
9364 err += efunc(pc, "invalid register %u\n", r1);
9365 if (r2 != 0)
9366 err += efunc(pc, "non-zero reserved bits\n");
9367 if (rd >= nregs)
9368 err += efunc(pc, "invalid register %u\n", rd);
9369 if (rd == 0)
9370 err += efunc(pc, "cannot write to %r0\n");
9371 break;
9372 case DIF_OP_STB:
9373 case DIF_OP_STH:
9374 case DIF_OP_STW:
9375 case DIF_OP_STX:
9376 if (r1 >= nregs)
9377 err += efunc(pc, "invalid register %u\n", r1);
9378 if (r2 != 0)
9379 err += efunc(pc, "non-zero reserved bits\n");
9380 if (rd >= nregs)
9381 err += efunc(pc, "invalid register %u\n", rd);
9382 if (rd == 0)
9383 err += efunc(pc, "cannot write to 0 address\n");
9384 break;
9385 case DIF_OP_CMP:
9386 case DIF_OP_SCMP:
9387 if (r1 >= nregs)
9388 err += efunc(pc, "invalid register %u\n", r1);
9389 if (r2 >= nregs)
9390 err += efunc(pc, "invalid register %u\n", r2);
9391 if (rd != 0)
9392 err += efunc(pc, "non-zero reserved bits\n");
9393 break;
9394 case DIF_OP_TST:
9395 if (r1 >= nregs)
9396 err += efunc(pc, "invalid register %u\n", r1);
9397 if (r2 != 0 || rd != 0)
9398 err += efunc(pc, "non-zero reserved bits\n");
9399 break;
9400 case DIF_OP_BA:
9401 case DIF_OP_BE:
9402 case DIF_OP_BNE:
9403 case DIF_OP_BG:
9404 case DIF_OP_BGU:
9405 case DIF_OP_BGE:
9406 case DIF_OP_BGEU:
9407 case DIF_OP_BL:
9408 case DIF_OP_BLU:
9409 case DIF_OP_BLE:
9410 case DIF_OP_BLEU:
9411 if (label >= dp->dtdo_len) {
9412 err += efunc(pc, "invalid branch target %u\n",
9413 label);
9414 }
9415 if (label <= pc) {
9416 err += efunc(pc, "backward branch to %u\n",
9417 label);
9418 }
9419 break;
9420 case DIF_OP_RET:
9421 if (r1 != 0 || r2 != 0)
9422 err += efunc(pc, "non-zero reserved bits\n");
9423 if (rd >= nregs)
9424 err += efunc(pc, "invalid register %u\n", rd);
9425 break;
9426 case DIF_OP_NOP:
9427 case DIF_OP_POPTS:
9428 case DIF_OP_FLUSHTS:
9429 if (r1 != 0 || r2 != 0 || rd != 0)
9430 err += efunc(pc, "non-zero reserved bits\n");
9431 break;
9432 case DIF_OP_SETX:
9433 if (DIF_INSTR_INTEGER(instr) >= dp->dtdo_intlen) {
9434 err += efunc(pc, "invalid integer ref %u\n",
9435 DIF_INSTR_INTEGER(instr));
9436 }
9437 if (rd >= nregs)
9438 err += efunc(pc, "invalid register %u\n", rd);
9439 if (rd == 0)
9440 err += efunc(pc, "cannot write to %r0\n");
9441 break;
9442 case DIF_OP_SETS:
9443 if (DIF_INSTR_STRING(instr) >= dp->dtdo_strlen) {
9444 err += efunc(pc, "invalid string ref %u\n",
9445 DIF_INSTR_STRING(instr));
9446 }
9447 if (rd >= nregs)
9448 err += efunc(pc, "invalid register %u\n", rd);
9449 if (rd == 0)
9450 err += efunc(pc, "cannot write to %r0\n");
9451 break;
9452 case DIF_OP_LDGA:
9453 case DIF_OP_LDTA:
9454 if (r1 > DIF_VAR_ARRAY_MAX)
9455 err += efunc(pc, "invalid array %u\n", r1);
9456 if (r2 >= nregs)
9457 err += efunc(pc, "invalid register %u\n", r2);
9458 if (rd >= nregs)
9459 err += efunc(pc, "invalid register %u\n", rd);
9460 if (rd == 0)
9461 err += efunc(pc, "cannot write to %r0\n");
9462 break;
9463 case DIF_OP_STGA:
9464 if (r1 > DIF_VAR_ARRAY_MAX)
9465 err += efunc(pc, "invalid array %u\n", r1);
9466 if (r2 >= nregs)
9467 err += efunc(pc, "invalid register %u\n", r2);
9468 if (rd >= nregs)
9469 err += efunc(pc, "invalid register %u\n", rd);
9470 dp->dtdo_destructive = 1;
9471 break;
9472 case DIF_OP_LDGS:
9473 case DIF_OP_LDTS:
9474 case DIF_OP_LDLS:
9475 case DIF_OP_LDGAA:
9476 case DIF_OP_LDTAA:
9477 if (v < DIF_VAR_OTHER_MIN || v > DIF_VAR_OTHER_MAX)
9478 err += efunc(pc, "invalid variable %u\n", v);
9479 if (rd >= nregs)
9480 err += efunc(pc, "invalid register %u\n", rd);
9481 if (rd == 0)
9482 err += efunc(pc, "cannot write to %r0\n");
9483 break;
9484 case DIF_OP_STGS:
9485 case DIF_OP_STTS:
9486 case DIF_OP_STLS:
9487 case DIF_OP_STGAA:
9488 case DIF_OP_STTAA:
9489 if (v < DIF_VAR_OTHER_UBASE || v > DIF_VAR_OTHER_MAX)
9490 err += efunc(pc, "invalid variable %u\n", v);
9491 if (rs >= nregs)
9492 err += efunc(pc, "invalid register %u\n", rd);
9493 break;
9494 case DIF_OP_CALL:
9495 if (subr > DIF_SUBR_MAX)
9496 err += efunc(pc, "invalid subr %u\n", subr);
9497 if (rd >= nregs)
9498 err += efunc(pc, "invalid register %u\n", rd);
9499 if (rd == 0)
9500 err += efunc(pc, "cannot write to %r0\n");
9501
9502 if (subr == DIF_SUBR_COPYOUT ||
9503 subr == DIF_SUBR_COPYOUTSTR) {
9504 dp->dtdo_destructive = 1;
9505 }
9506
9507 if (subr == DIF_SUBR_GETF) {
9508 /*
9509 * If we have a getf() we need to record that
9510 * in our state. Note that our state can be
9511 * NULL if this is a helper -- but in that
9512 * case, the call to getf() is itself illegal,
9513 * and will be caught (slightly later) when
9514 * the helper is validated.
9515 */
9516 if (vstate->dtvs_state != NULL)
9517 vstate->dtvs_state->dts_getf++;
9518 }
9519
9520 break;
9521 case DIF_OP_PUSHTR:
9522 if (type != DIF_TYPE_STRING && type != DIF_TYPE_CTF)
9523 err += efunc(pc, "invalid ref type %u\n", type);
9524 if (r2 >= nregs)
9525 err += efunc(pc, "invalid register %u\n", r2);
9526 if (rs >= nregs)
9527 err += efunc(pc, "invalid register %u\n", rs);
9528 break;
9529 case DIF_OP_PUSHTV:
9530 if (type != DIF_TYPE_CTF)
9531 err += efunc(pc, "invalid val type %u\n", type);
9532 if (r2 >= nregs)
9533 err += efunc(pc, "invalid register %u\n", r2);
9534 if (rs >= nregs)
9535 err += efunc(pc, "invalid register %u\n", rs);
9536 break;
9537 default:
9538 err += efunc(pc, "invalid opcode %u\n",
9539 DIF_INSTR_OP(instr));
9540 }
9541 }
9542
9543 if (dp->dtdo_len != 0 &&
9544 DIF_INSTR_OP(dp->dtdo_buf[dp->dtdo_len - 1]) != DIF_OP_RET) {
9545 err += efunc(dp->dtdo_len - 1,
9546 "expected 'ret' as last DIF instruction\n");
9547 }
9548
9549 if (!(dp->dtdo_rtype.dtdt_flags & (DIF_TF_BYREF | DIF_TF_BYUREF))) {
9550 /*
9551 * If we're not returning by reference, the size must be either
9552 * 0 or the size of one of the base types.
9553 */
9554 switch (dp->dtdo_rtype.dtdt_size) {
9555 case 0:
9556 case sizeof (uint8_t):
9557 case sizeof (uint16_t):
9558 case sizeof (uint32_t):
9559 case sizeof (uint64_t):
9560 break;
9561
9562 default:
9563 err += efunc(dp->dtdo_len - 1, "bad return size\n");
9564 }
9565 }
9566
9567 for (i = 0; i < dp->dtdo_varlen && err == 0; i++) {
9568 dtrace_difv_t *v = &dp->dtdo_vartab[i], *existing = NULL;
9569 dtrace_diftype_t *vt, *et;
9570 uint_t id, ndx;
9571
9572 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL &&
9573 v->dtdv_scope != DIFV_SCOPE_THREAD &&
9574 v->dtdv_scope != DIFV_SCOPE_LOCAL) {
9575 err += efunc(i, "unrecognized variable scope %d\n",
9576 v->dtdv_scope);
9577 break;
9578 }
9579
9580 if (v->dtdv_kind != DIFV_KIND_ARRAY &&
9581 v->dtdv_kind != DIFV_KIND_SCALAR) {
9582 err += efunc(i, "unrecognized variable type %d\n",
9583 v->dtdv_kind);
9584 break;
9585 }
9586
9587 if ((id = v->dtdv_id) > DIF_VARIABLE_MAX) {
9588 err += efunc(i, "%d exceeds variable id limit\n", id);
9589 break;
9590 }
9591
9592 if (id < DIF_VAR_OTHER_UBASE)
9593 continue;
9594
9595 /*
9596 * For user-defined variables, we need to check that this
9597 * definition is identical to any previous definition that we
9598 * encountered.
9599 */
9600 ndx = id - DIF_VAR_OTHER_UBASE;
9601
9602 switch (v->dtdv_scope) {
9603 case DIFV_SCOPE_GLOBAL:
9604 if (maxglobal == -1 || ndx > maxglobal)
9605 maxglobal = ndx;
9606
9607 if (ndx < vstate->dtvs_nglobals) {
9608 dtrace_statvar_t *svar;
9609
9610 if ((svar = vstate->dtvs_globals[ndx]) != NULL)
9611 existing = &svar->dtsv_var;
9612 }
9613
9614 break;
9615
9616 case DIFV_SCOPE_THREAD:
9617 if (maxtlocal == -1 || ndx > maxtlocal)
9618 maxtlocal = ndx;
9619
9620 if (ndx < vstate->dtvs_ntlocals)
9621 existing = &vstate->dtvs_tlocals[ndx];
9622 break;
9623
9624 case DIFV_SCOPE_LOCAL:
9625 if (maxlocal == -1 || ndx > maxlocal)
9626 maxlocal = ndx;
9627
9628 if (ndx < vstate->dtvs_nlocals) {
9629 dtrace_statvar_t *svar;
9630
9631 if ((svar = vstate->dtvs_locals[ndx]) != NULL)
9632 existing = &svar->dtsv_var;
9633 }
9634
9635 break;
9636 }
9637
9638 vt = &v->dtdv_type;
9639
9640 if (vt->dtdt_flags & DIF_TF_BYREF) {
9641 if (vt->dtdt_size == 0) {
9642 err += efunc(i, "zero-sized variable\n");
9643 break;
9644 }
9645
9646 if ((v->dtdv_scope == DIFV_SCOPE_GLOBAL ||
9647 v->dtdv_scope == DIFV_SCOPE_LOCAL) &&
9648 vt->dtdt_size > dtrace_statvar_maxsize) {
9649 err += efunc(i, "oversized by-ref static\n");
9650 break;
9651 }
9652 }
9653
9654 if (existing == NULL || existing->dtdv_id == 0)
9655 continue;
9656
9657 ASSERT(existing->dtdv_id == v->dtdv_id);
9658 ASSERT(existing->dtdv_scope == v->dtdv_scope);
9659
9660 if (existing->dtdv_kind != v->dtdv_kind)
9661 err += efunc(i, "%d changed variable kind\n", id);
9662
9663 et = &existing->dtdv_type;
9664
9665 if (vt->dtdt_flags != et->dtdt_flags) {
9666 err += efunc(i, "%d changed variable type flags\n", id);
9667 break;
9668 }
9669
9670 if (vt->dtdt_size != 0 && vt->dtdt_size != et->dtdt_size) {
9671 err += efunc(i, "%d changed variable type size\n", id);
9672 break;
9673 }
9674 }
9675
9676 for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) {
9677 dif_instr_t instr = dp->dtdo_buf[pc];
9678
9679 uint_t v = DIF_INSTR_VAR(instr);
9680 uint_t op = DIF_INSTR_OP(instr);
9681
9682 switch (op) {
9683 case DIF_OP_LDGS:
9684 case DIF_OP_LDGAA:
9685 case DIF_OP_STGS:
9686 case DIF_OP_STGAA:
9687 if (v > DIF_VAR_OTHER_UBASE + maxglobal)
9688 err += efunc(pc, "invalid variable %u\n", v);
9689 break;
9690 case DIF_OP_LDTS:
9691 case DIF_OP_LDTAA:
9692 case DIF_OP_STTS:
9693 case DIF_OP_STTAA:
9694 if (v > DIF_VAR_OTHER_UBASE + maxtlocal)
9695 err += efunc(pc, "invalid variable %u\n", v);
9696 break;
9697 case DIF_OP_LDLS:
9698 case DIF_OP_STLS:
9699 if (v > DIF_VAR_OTHER_UBASE + maxlocal)
9700 err += efunc(pc, "invalid variable %u\n", v);
9701 break;
9702 default:
9703 break;
9704 }
9705 }
9706
9707 return (err);
9708 }
9709
9710 /*
9711 * Validate a DTrace DIF object that it is to be used as a helper. Helpers
9712 * are much more constrained than normal DIFOs. Specifically, they may
9713 * not:
9714 *
9715 * 1. Make calls to subroutines other than copyin(), copyinstr() or
9716 * miscellaneous string routines
9717 * 2. Access DTrace variables other than the args[] array, and the
9718 * curthread, pid, ppid, tid, execname, zonename, uid and gid variables.
9719 * 3. Have thread-local variables.
9720 * 4. Have dynamic variables.
9721 */
9722 static int
9723 dtrace_difo_validate_helper(dtrace_difo_t *dp)
9724 {
9725 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
9726 int err = 0;
9727 uint_t pc;
9728
9729 for (pc = 0; pc < dp->dtdo_len; pc++) {
9730 dif_instr_t instr = dp->dtdo_buf[pc];
9731
9732 uint_t v = DIF_INSTR_VAR(instr);
9733 uint_t subr = DIF_INSTR_SUBR(instr);
9734 uint_t op = DIF_INSTR_OP(instr);
9735
9736 switch (op) {
9737 case DIF_OP_OR:
9738 case DIF_OP_XOR:
9739 case DIF_OP_AND:
9740 case DIF_OP_SLL:
9741 case DIF_OP_SRL:
9742 case DIF_OP_SRA:
9743 case DIF_OP_SUB:
9744 case DIF_OP_ADD:
9745 case DIF_OP_MUL:
9746 case DIF_OP_SDIV:
9747 case DIF_OP_UDIV:
9748 case DIF_OP_SREM:
9749 case DIF_OP_UREM:
9750 case DIF_OP_COPYS:
9751 case DIF_OP_NOT:
9752 case DIF_OP_MOV:
9753 case DIF_OP_RLDSB:
9754 case DIF_OP_RLDSH:
9755 case DIF_OP_RLDSW:
9756 case DIF_OP_RLDUB:
9757 case DIF_OP_RLDUH:
9758 case DIF_OP_RLDUW:
9759 case DIF_OP_RLDX:
9760 case DIF_OP_ULDSB:
9761 case DIF_OP_ULDSH:
9762 case DIF_OP_ULDSW:
9763 case DIF_OP_ULDUB:
9764 case DIF_OP_ULDUH:
9765 case DIF_OP_ULDUW:
9766 case DIF_OP_ULDX:
9767 case DIF_OP_STB:
9768 case DIF_OP_STH:
9769 case DIF_OP_STW:
9770 case DIF_OP_STX:
9771 case DIF_OP_ALLOCS:
9772 case DIF_OP_CMP:
9773 case DIF_OP_SCMP:
9774 case DIF_OP_TST:
9775 case DIF_OP_BA:
9776 case DIF_OP_BE:
9777 case DIF_OP_BNE:
9778 case DIF_OP_BG:
9779 case DIF_OP_BGU:
9780 case DIF_OP_BGE:
9781 case DIF_OP_BGEU:
9782 case DIF_OP_BL:
9783 case DIF_OP_BLU:
9784 case DIF_OP_BLE:
9785 case DIF_OP_BLEU:
9786 case DIF_OP_RET:
9787 case DIF_OP_NOP:
9788 case DIF_OP_POPTS:
9789 case DIF_OP_FLUSHTS:
9790 case DIF_OP_SETX:
9791 case DIF_OP_SETS:
9792 case DIF_OP_LDGA:
9793 case DIF_OP_LDLS:
9794 case DIF_OP_STGS:
9795 case DIF_OP_STLS:
9796 case DIF_OP_PUSHTR:
9797 case DIF_OP_PUSHTV:
9798 break;
9799
9800 case DIF_OP_LDGS:
9801 if (v >= DIF_VAR_OTHER_UBASE)
9802 break;
9803
9804 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9)
9805 break;
9806
9807 if (v == DIF_VAR_CURTHREAD || v == DIF_VAR_PID ||
9808 v == DIF_VAR_PPID || v == DIF_VAR_TID ||
9809 v == DIF_VAR_EXECNAME || v == DIF_VAR_ZONENAME ||
9810 v == DIF_VAR_UID || v == DIF_VAR_GID)
9811 break;
9812
9813 err += efunc(pc, "illegal variable %u\n", v);
9814 break;
9815
9816 case DIF_OP_LDTA:
9817 if (v < DIF_VAR_OTHER_UBASE) {
9818 err += efunc(pc, "illegal variable load\n");
9819 break;
9820 }
9821 /* FALLTHROUGH */
9822 case DIF_OP_LDTS:
9823 case DIF_OP_LDGAA:
9824 case DIF_OP_LDTAA:
9825 err += efunc(pc, "illegal dynamic variable load\n");
9826 break;
9827
9828 case DIF_OP_STGA:
9829 if (v < DIF_VAR_OTHER_UBASE) {
9830 err += efunc(pc, "illegal variable store\n");
9831 break;
9832 }
9833 /* FALLTHROUGH */
9834 case DIF_OP_STTS:
9835 case DIF_OP_STGAA:
9836 case DIF_OP_STTAA:
9837 err += efunc(pc, "illegal dynamic variable store\n");
9838 break;
9839
9840 case DIF_OP_CALL:
9841 if (subr == DIF_SUBR_ALLOCA ||
9842 subr == DIF_SUBR_BCOPY ||
9843 subr == DIF_SUBR_COPYIN ||
9844 subr == DIF_SUBR_COPYINTO ||
9845 subr == DIF_SUBR_COPYINSTR ||
9846 subr == DIF_SUBR_INDEX ||
9847 subr == DIF_SUBR_INET_NTOA ||
9848 subr == DIF_SUBR_INET_NTOA6 ||
9849 subr == DIF_SUBR_INET_NTOP ||
9850 subr == DIF_SUBR_JSON ||
9851 subr == DIF_SUBR_LLTOSTR ||
9852 subr == DIF_SUBR_STRTOLL ||
9853 subr == DIF_SUBR_RINDEX ||
9854 subr == DIF_SUBR_STRCHR ||
9855 subr == DIF_SUBR_STRJOIN ||
9856 subr == DIF_SUBR_STRRCHR ||
9857 subr == DIF_SUBR_STRSTR ||
9858 subr == DIF_SUBR_HTONS ||
9859 subr == DIF_SUBR_HTONL ||
9860 subr == DIF_SUBR_HTONLL ||
9861 subr == DIF_SUBR_NTOHS ||
9862 subr == DIF_SUBR_NTOHL ||
9863 subr == DIF_SUBR_NTOHLL)
9864 break;
9865
9866 err += efunc(pc, "invalid subr %u\n", subr);
9867 break;
9868
9869 default:
9870 err += efunc(pc, "invalid opcode %u\n",
9871 DIF_INSTR_OP(instr));
9872 }
9873 }
9874
9875 return (err);
9876 }
9877
9878 /*
9879 * Returns 1 if the expression in the DIF object can be cached on a per-thread
9880 * basis; 0 if not.
9881 */
9882 static int
9883 dtrace_difo_cacheable(dtrace_difo_t *dp)
9884 {
9885 int i;
9886
9887 if (dp == NULL)
9888 return (0);
9889
9890 for (i = 0; i < dp->dtdo_varlen; i++) {
9891 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9892
9893 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL)
9894 continue;
9895
9896 switch (v->dtdv_id) {
9897 case DIF_VAR_CURTHREAD:
9898 case DIF_VAR_PID:
9899 case DIF_VAR_TID:
9900 case DIF_VAR_EXECNAME:
9901 case DIF_VAR_ZONENAME:
9902 break;
9903
9904 default:
9905 return (0);
9906 }
9907 }
9908
9909 /*
9910 * This DIF object may be cacheable. Now we need to look for any
9911 * array loading instructions, any memory loading instructions, or
9912 * any stores to thread-local variables.
9913 */
9914 for (i = 0; i < dp->dtdo_len; i++) {
9915 uint_t op = DIF_INSTR_OP(dp->dtdo_buf[i]);
9916
9917 if ((op >= DIF_OP_LDSB && op <= DIF_OP_LDX) ||
9918 (op >= DIF_OP_ULDSB && op <= DIF_OP_ULDX) ||
9919 (op >= DIF_OP_RLDSB && op <= DIF_OP_RLDX) ||
9920 op == DIF_OP_LDGA || op == DIF_OP_STTS)
9921 return (0);
9922 }
9923
9924 return (1);
9925 }
9926
9927 static void
9928 dtrace_difo_hold(dtrace_difo_t *dp)
9929 {
9930 int i;
9931
9932 ASSERT(MUTEX_HELD(&dtrace_lock));
9933
9934 dp->dtdo_refcnt++;
9935 ASSERT(dp->dtdo_refcnt != 0);
9936
9937 /*
9938 * We need to check this DIF object for references to the variable
9939 * DIF_VAR_VTIMESTAMP.
9940 */
9941 for (i = 0; i < dp->dtdo_varlen; i++) {
9942 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9943
9944 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
9945 continue;
9946
9947 if (dtrace_vtime_references++ == 0)
9948 dtrace_vtime_enable();
9949 }
9950 }
9951
9952 /*
9953 * This routine calculates the dynamic variable chunksize for a given DIF
9954 * object. The calculation is not fool-proof, and can probably be tricked by
9955 * malicious DIF -- but it works for all compiler-generated DIF. Because this
9956 * calculation is likely imperfect, dtrace_dynvar() is able to gracefully fail
9957 * if a dynamic variable size exceeds the chunksize.
9958 */
9959 static void
9960 dtrace_difo_chunksize(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9961 {
9962 uint64_t sval;
9963 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
9964 const dif_instr_t *text = dp->dtdo_buf;
9965 uint_t pc, srd = 0;
9966 uint_t ttop = 0;
9967 size_t size, ksize;
9968 uint_t id, i;
9969
9970 for (pc = 0; pc < dp->dtdo_len; pc++) {
9971 dif_instr_t instr = text[pc];
9972 uint_t op = DIF_INSTR_OP(instr);
9973 uint_t rd = DIF_INSTR_RD(instr);
9974 uint_t r1 = DIF_INSTR_R1(instr);
9975 uint_t nkeys = 0;
9976 uchar_t scope;
9977
9978 dtrace_key_t *key = tupregs;
9979
9980 switch (op) {
9981 case DIF_OP_SETX:
9982 sval = dp->dtdo_inttab[DIF_INSTR_INTEGER(instr)];
9983 srd = rd;
9984 continue;
9985
9986 case DIF_OP_STTS:
9987 key = &tupregs[DIF_DTR_NREGS];
9988 key[0].dttk_size = 0;
9989 key[1].dttk_size = 0;
9990 nkeys = 2;
9991 scope = DIFV_SCOPE_THREAD;
9992 break;
9993
9994 case DIF_OP_STGAA:
9995 case DIF_OP_STTAA:
9996 nkeys = ttop;
9997
9998 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA)
9999 key[nkeys++].dttk_size = 0;
10000
10001 key[nkeys++].dttk_size = 0;
10002
10003 if (op == DIF_OP_STTAA) {
10004 scope = DIFV_SCOPE_THREAD;
10005 } else {
10006 scope = DIFV_SCOPE_GLOBAL;
10007 }
10008
10009 break;
10010
10011 case DIF_OP_PUSHTR:
10012 if (ttop == DIF_DTR_NREGS)
10013 return;
10014
10015 if ((srd == 0 || sval == 0) && r1 == DIF_TYPE_STRING) {
10016 /*
10017 * If the register for the size of the "pushtr"
10018 * is %r0 (or the value is 0) and the type is
10019 * a string, we'll use the system-wide default
10020 * string size.
10021 */
10022 tupregs[ttop++].dttk_size =
10023 dtrace_strsize_default;
10024 } else {
10025 if (srd == 0)
10026 return;
10027
10028 if (sval > LONG_MAX)
10029 return;
10030
10031 tupregs[ttop++].dttk_size = sval;
10032 }
10033
10034 break;
10035
10036 case DIF_OP_PUSHTV:
10037 if (ttop == DIF_DTR_NREGS)
10038 return;
10039
10040 tupregs[ttop++].dttk_size = 0;
10041 break;
10042
10043 case DIF_OP_FLUSHTS:
10044 ttop = 0;
10045 break;
10046
10047 case DIF_OP_POPTS:
10048 if (ttop != 0)
10049 ttop--;
10050 break;
10051 }
10052
10053 sval = 0;
10054 srd = 0;
10055
10056 if (nkeys == 0)
10057 continue;
10058
10059 /*
10060 * We have a dynamic variable allocation; calculate its size.
10061 */
10062 for (ksize = 0, i = 0; i < nkeys; i++)
10063 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
10064
10065 size = sizeof (dtrace_dynvar_t);
10066 size += sizeof (dtrace_key_t) * (nkeys - 1);
10067 size += ksize;
10068
10069 /*
10070 * Now we need to determine the size of the stored data.
10071 */
10072 id = DIF_INSTR_VAR(instr);
10073
10074 for (i = 0; i < dp->dtdo_varlen; i++) {
10075 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10076
10077 if (v->dtdv_id == id && v->dtdv_scope == scope) {
10078 size += v->dtdv_type.dtdt_size;
10079 break;
10080 }
10081 }
10082
10083 if (i == dp->dtdo_varlen)
10084 return;
10085
10086 /*
10087 * We have the size. If this is larger than the chunk size
10088 * for our dynamic variable state, reset the chunk size.
10089 */
10090 size = P2ROUNDUP(size, sizeof (uint64_t));
10091
10092 /*
10093 * Before setting the chunk size, check that we're not going
10094 * to set it to a negative value...
10095 */
10096 if (size > LONG_MAX)
10097 return;
10098
10099 /*
10100 * ...and make certain that we didn't badly overflow.
10101 */
10102 if (size < ksize || size < sizeof (dtrace_dynvar_t))
10103 return;
10104
10105 if (size > vstate->dtvs_dynvars.dtds_chunksize)
10106 vstate->dtvs_dynvars.dtds_chunksize = size;
10107 }
10108 }
10109
10110 static void
10111 dtrace_difo_init(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10112 {
10113 int i, oldsvars, osz, nsz, otlocals, ntlocals;
10114 uint_t id;
10115
10116 ASSERT(MUTEX_HELD(&dtrace_lock));
10117 ASSERT(dp->dtdo_buf != NULL && dp->dtdo_len != 0);
10118
10119 for (i = 0; i < dp->dtdo_varlen; i++) {
10120 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10121 dtrace_statvar_t *svar, ***svarp;
10122 size_t dsize = 0;
10123 uint8_t scope = v->dtdv_scope;
10124 int *np;
10125
10126 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
10127 continue;
10128
10129 id -= DIF_VAR_OTHER_UBASE;
10130
10131 switch (scope) {
10132 case DIFV_SCOPE_THREAD:
10133 while (id >= (otlocals = vstate->dtvs_ntlocals)) {
10134 dtrace_difv_t *tlocals;
10135
10136 if ((ntlocals = (otlocals << 1)) == 0)
10137 ntlocals = 1;
10138
10139 osz = otlocals * sizeof (dtrace_difv_t);
10140 nsz = ntlocals * sizeof (dtrace_difv_t);
10141
10142 tlocals = kmem_zalloc(nsz, KM_SLEEP);
10143
10144 if (osz != 0) {
10145 bcopy(vstate->dtvs_tlocals,
10146 tlocals, osz);
10147 kmem_free(vstate->dtvs_tlocals, osz);
10148 }
10149
10150 vstate->dtvs_tlocals = tlocals;
10151 vstate->dtvs_ntlocals = ntlocals;
10152 }
10153
10154 vstate->dtvs_tlocals[id] = *v;
10155 continue;
10156
10157 case DIFV_SCOPE_LOCAL:
10158 np = &vstate->dtvs_nlocals;
10159 svarp = &vstate->dtvs_locals;
10160
10161 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
10162 dsize = NCPU * (v->dtdv_type.dtdt_size +
10163 sizeof (uint64_t));
10164 else
10165 dsize = NCPU * sizeof (uint64_t);
10166
10167 break;
10168
10169 case DIFV_SCOPE_GLOBAL:
10170 np = &vstate->dtvs_nglobals;
10171 svarp = &vstate->dtvs_globals;
10172
10173 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
10174 dsize = v->dtdv_type.dtdt_size +
10175 sizeof (uint64_t);
10176
10177 break;
10178
10179 default:
10180 ASSERT(0);
10181 }
10182
10183 while (id >= (oldsvars = *np)) {
10184 dtrace_statvar_t **statics;
10185 int newsvars, oldsize, newsize;
10186
10187 if ((newsvars = (oldsvars << 1)) == 0)
10188 newsvars = 1;
10189
10190 oldsize = oldsvars * sizeof (dtrace_statvar_t *);
10191 newsize = newsvars * sizeof (dtrace_statvar_t *);
10192
10193 statics = kmem_zalloc(newsize, KM_SLEEP);
10194
10195 if (oldsize != 0) {
10196 bcopy(*svarp, statics, oldsize);
10197 kmem_free(*svarp, oldsize);
10198 }
10199
10200 *svarp = statics;
10201 *np = newsvars;
10202 }
10203
10204 if ((svar = (*svarp)[id]) == NULL) {
10205 svar = kmem_zalloc(sizeof (dtrace_statvar_t), KM_SLEEP);
10206 svar->dtsv_var = *v;
10207
10208 if ((svar->dtsv_size = dsize) != 0) {
10209 svar->dtsv_data = (uint64_t)(uintptr_t)
10210 kmem_zalloc(dsize, KM_SLEEP);
10211 }
10212
10213 (*svarp)[id] = svar;
10214 }
10215
10216 svar->dtsv_refcnt++;
10217 }
10218
10219 dtrace_difo_chunksize(dp, vstate);
10220 dtrace_difo_hold(dp);
10221 }
10222
10223 static dtrace_difo_t *
10224 dtrace_difo_duplicate(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10225 {
10226 dtrace_difo_t *new;
10227 size_t sz;
10228
10229 ASSERT(dp->dtdo_buf != NULL);
10230 ASSERT(dp->dtdo_refcnt != 0);
10231
10232 new = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
10233
10234 ASSERT(dp->dtdo_buf != NULL);
10235 sz = dp->dtdo_len * sizeof (dif_instr_t);
10236 new->dtdo_buf = kmem_alloc(sz, KM_SLEEP);
10237 bcopy(dp->dtdo_buf, new->dtdo_buf, sz);
10238 new->dtdo_len = dp->dtdo_len;
10239
10240 if (dp->dtdo_strtab != NULL) {
10241 ASSERT(dp->dtdo_strlen != 0);
10242 new->dtdo_strtab = kmem_alloc(dp->dtdo_strlen, KM_SLEEP);
10243 bcopy(dp->dtdo_strtab, new->dtdo_strtab, dp->dtdo_strlen);
10244 new->dtdo_strlen = dp->dtdo_strlen;
10245 }
10246
10247 if (dp->dtdo_inttab != NULL) {
10248 ASSERT(dp->dtdo_intlen != 0);
10249 sz = dp->dtdo_intlen * sizeof (uint64_t);
10250 new->dtdo_inttab = kmem_alloc(sz, KM_SLEEP);
10251 bcopy(dp->dtdo_inttab, new->dtdo_inttab, sz);
10252 new->dtdo_intlen = dp->dtdo_intlen;
10253 }
10254
10255 if (dp->dtdo_vartab != NULL) {
10256 ASSERT(dp->dtdo_varlen != 0);
10257 sz = dp->dtdo_varlen * sizeof (dtrace_difv_t);
10258 new->dtdo_vartab = kmem_alloc(sz, KM_SLEEP);
10259 bcopy(dp->dtdo_vartab, new->dtdo_vartab, sz);
10260 new->dtdo_varlen = dp->dtdo_varlen;
10261 }
10262
10263 dtrace_difo_init(new, vstate);
10264 return (new);
10265 }
10266
10267 static void
10268 dtrace_difo_destroy(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10269 {
10270 int i;
10271
10272 ASSERT(dp->dtdo_refcnt == 0);
10273
10274 for (i = 0; i < dp->dtdo_varlen; i++) {
10275 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10276 dtrace_statvar_t *svar, **svarp;
10277 uint_t id;
10278 uint8_t scope = v->dtdv_scope;
10279 int *np;
10280
10281 switch (scope) {
10282 case DIFV_SCOPE_THREAD:
10283 continue;
10284
10285 case DIFV_SCOPE_LOCAL:
10286 np = &vstate->dtvs_nlocals;
10287 svarp = vstate->dtvs_locals;
10288 break;
10289
10290 case DIFV_SCOPE_GLOBAL:
10291 np = &vstate->dtvs_nglobals;
10292 svarp = vstate->dtvs_globals;
10293 break;
10294
10295 default:
10296 ASSERT(0);
10297 }
10298
10299 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
10300 continue;
10301
10302 id -= DIF_VAR_OTHER_UBASE;
10303 ASSERT(id < *np);
10304
10305 svar = svarp[id];
10306 ASSERT(svar != NULL);
10307 ASSERT(svar->dtsv_refcnt > 0);
10308
10309 if (--svar->dtsv_refcnt > 0)
10310 continue;
10311
10312 if (svar->dtsv_size != 0) {
10313 ASSERT(svar->dtsv_data != 0);
10314 kmem_free((void *)(uintptr_t)svar->dtsv_data,
10315 svar->dtsv_size);
10316 }
10317
10318 kmem_free(svar, sizeof (dtrace_statvar_t));
10319 svarp[id] = NULL;
10320 }
10321
10322 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
10323 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
10324 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
10325 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
10326
10327 kmem_free(dp, sizeof (dtrace_difo_t));
10328 }
10329
10330 static void
10331 dtrace_difo_release(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10332 {
10333 int i;
10334
10335 ASSERT(MUTEX_HELD(&dtrace_lock));
10336 ASSERT(dp->dtdo_refcnt != 0);
10337
10338 for (i = 0; i < dp->dtdo_varlen; i++) {
10339 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10340
10341 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
10342 continue;
10343
10344 ASSERT(dtrace_vtime_references > 0);
10345 if (--dtrace_vtime_references == 0)
10346 dtrace_vtime_disable();
10347 }
10348
10349 if (--dp->dtdo_refcnt == 0)
10350 dtrace_difo_destroy(dp, vstate);
10351 }
10352
10353 /*
10354 * DTrace Format Functions
10355 */
10356 static uint16_t
10357 dtrace_format_add(dtrace_state_t *state, char *str)
10358 {
10359 char *fmt, **new;
10360 uint16_t ndx, len = strlen(str) + 1;
10361
10362 fmt = kmem_zalloc(len, KM_SLEEP);
10363 bcopy(str, fmt, len);
10364
10365 for (ndx = 0; ndx < state->dts_nformats; ndx++) {
10366 if (state->dts_formats[ndx] == NULL) {
10367 state->dts_formats[ndx] = fmt;
10368 return (ndx + 1);
10369 }
10370 }
10371
10372 if (state->dts_nformats == USHRT_MAX) {
10373 /*
10374 * This is only likely if a denial-of-service attack is being
10375 * attempted. As such, it's okay to fail silently here.
10376 */
10377 kmem_free(fmt, len);
10378 return (0);
10379 }
10380
10381 /*
10382 * For simplicity, we always resize the formats array to be exactly the
10383 * number of formats.
10384 */
10385 ndx = state->dts_nformats++;
10386 new = kmem_alloc((ndx + 1) * sizeof (char *), KM_SLEEP);
10387
10388 if (state->dts_formats != NULL) {
10389 ASSERT(ndx != 0);
10390 bcopy(state->dts_formats, new, ndx * sizeof (char *));
10391 kmem_free(state->dts_formats, ndx * sizeof (char *));
10392 }
10393
10394 state->dts_formats = new;
10395 state->dts_formats[ndx] = fmt;
10396
10397 return (ndx + 1);
10398 }
10399
10400 static void
10401 dtrace_format_remove(dtrace_state_t *state, uint16_t format)
10402 {
10403 char *fmt;
10404
10405 ASSERT(state->dts_formats != NULL);
10406 ASSERT(format <= state->dts_nformats);
10407 ASSERT(state->dts_formats[format - 1] != NULL);
10408
10409 fmt = state->dts_formats[format - 1];
10410 kmem_free(fmt, strlen(fmt) + 1);
10411 state->dts_formats[format - 1] = NULL;
10412 }
10413
10414 static void
10415 dtrace_format_destroy(dtrace_state_t *state)
10416 {
10417 int i;
10418
10419 if (state->dts_nformats == 0) {
10420 ASSERT(state->dts_formats == NULL);
10421 return;
10422 }
10423
10424 ASSERT(state->dts_formats != NULL);
10425
10426 for (i = 0; i < state->dts_nformats; i++) {
10427 char *fmt = state->dts_formats[i];
10428
10429 if (fmt == NULL)
10430 continue;
10431
10432 kmem_free(fmt, strlen(fmt) + 1);
10433 }
10434
10435 kmem_free(state->dts_formats, state->dts_nformats * sizeof (char *));
10436 state->dts_nformats = 0;
10437 state->dts_formats = NULL;
10438 }
10439
10440 /*
10441 * DTrace Predicate Functions
10442 */
10443 static dtrace_predicate_t *
10444 dtrace_predicate_create(dtrace_difo_t *dp)
10445 {
10446 dtrace_predicate_t *pred;
10447
10448 ASSERT(MUTEX_HELD(&dtrace_lock));
10449 ASSERT(dp->dtdo_refcnt != 0);
10450
10451 pred = kmem_zalloc(sizeof (dtrace_predicate_t), KM_SLEEP);
10452 pred->dtp_difo = dp;
10453 pred->dtp_refcnt = 1;
10454
10455 if (!dtrace_difo_cacheable(dp))
10456 return (pred);
10457
10458 if (dtrace_predcache_id == DTRACE_CACHEIDNONE) {
10459 /*
10460 * This is only theoretically possible -- we have had 2^32
10461 * cacheable predicates on this machine. We cannot allow any
10462 * more predicates to become cacheable: as unlikely as it is,
10463 * there may be a thread caching a (now stale) predicate cache
10464 * ID. (N.B.: the temptation is being successfully resisted to
10465 * have this cmn_err() "Holy shit -- we executed this code!")
10466 */
10467 return (pred);
10468 }
10469
10470 pred->dtp_cacheid = dtrace_predcache_id++;
10471
10472 return (pred);
10473 }
10474
10475 static void
10476 dtrace_predicate_hold(dtrace_predicate_t *pred)
10477 {
10478 ASSERT(MUTEX_HELD(&dtrace_lock));
10479 ASSERT(pred->dtp_difo != NULL && pred->dtp_difo->dtdo_refcnt != 0);
10480 ASSERT(pred->dtp_refcnt > 0);
10481
10482 pred->dtp_refcnt++;
10483 }
10484
10485 static void
10486 dtrace_predicate_release(dtrace_predicate_t *pred, dtrace_vstate_t *vstate)
10487 {
10488 dtrace_difo_t *dp = pred->dtp_difo;
10489
10490 ASSERT(MUTEX_HELD(&dtrace_lock));
10491 ASSERT(dp != NULL && dp->dtdo_refcnt != 0);
10492 ASSERT(pred->dtp_refcnt > 0);
10493
10494 if (--pred->dtp_refcnt == 0) {
10495 dtrace_difo_release(pred->dtp_difo, vstate);
10496 kmem_free(pred, sizeof (dtrace_predicate_t));
10497 }
10498 }
10499
10500 /*
10501 * DTrace Action Description Functions
10502 */
10503 static dtrace_actdesc_t *
10504 dtrace_actdesc_create(dtrace_actkind_t kind, uint32_t ntuple,
10505 uint64_t uarg, uint64_t arg)
10506 {
10507 dtrace_actdesc_t *act;
10508
10509 ASSERT(!DTRACEACT_ISPRINTFLIKE(kind) || (arg != 0 &&
10510 arg >= KERNELBASE) || (arg == 0 && kind == DTRACEACT_PRINTA));
10511
10512 act = kmem_zalloc(sizeof (dtrace_actdesc_t), KM_SLEEP);
10513 act->dtad_kind = kind;
10514 act->dtad_ntuple = ntuple;
10515 act->dtad_uarg = uarg;
10516 act->dtad_arg = arg;
10517 act->dtad_refcnt = 1;
10518
10519 return (act);
10520 }
10521
10522 static void
10523 dtrace_actdesc_hold(dtrace_actdesc_t *act)
10524 {
10525 ASSERT(act->dtad_refcnt >= 1);
10526 act->dtad_refcnt++;
10527 }
10528
10529 static void
10530 dtrace_actdesc_release(dtrace_actdesc_t *act, dtrace_vstate_t *vstate)
10531 {
10532 dtrace_actkind_t kind = act->dtad_kind;
10533 dtrace_difo_t *dp;
10534
10535 ASSERT(act->dtad_refcnt >= 1);
10536
10537 if (--act->dtad_refcnt != 0)
10538 return;
10539
10540 if ((dp = act->dtad_difo) != NULL)
10541 dtrace_difo_release(dp, vstate);
10542
10543 if (DTRACEACT_ISPRINTFLIKE(kind)) {
10544 char *str = (char *)(uintptr_t)act->dtad_arg;
10545
10546 ASSERT((str != NULL && (uintptr_t)str >= KERNELBASE) ||
10547 (str == NULL && act->dtad_kind == DTRACEACT_PRINTA));
10548
10549 if (str != NULL)
10550 kmem_free(str, strlen(str) + 1);
10551 }
10552
10553 kmem_free(act, sizeof (dtrace_actdesc_t));
10554 }
10555
10556 /*
10557 * DTrace ECB Functions
10558 */
10559 static dtrace_ecb_t *
10560 dtrace_ecb_add(dtrace_state_t *state, dtrace_probe_t *probe)
10561 {
10562 dtrace_ecb_t *ecb;
10563 dtrace_epid_t epid;
10564
10565 ASSERT(MUTEX_HELD(&dtrace_lock));
10566
10567 ecb = kmem_zalloc(sizeof (dtrace_ecb_t), KM_SLEEP);
10568 ecb->dte_predicate = NULL;
10569 ecb->dte_probe = probe;
10570
10571 /*
10572 * The default size is the size of the default action: recording
10573 * the header.
10574 */
10575 ecb->dte_size = ecb->dte_needed = sizeof (dtrace_rechdr_t);
10576 ecb->dte_alignment = sizeof (dtrace_epid_t);
10577
10578 epid = state->dts_epid++;
10579
10580 if (epid - 1 >= state->dts_necbs) {
10581 dtrace_ecb_t **oecbs = state->dts_ecbs, **ecbs;
10582 int necbs = state->dts_necbs << 1;
10583
10584 ASSERT(epid == state->dts_necbs + 1);
10585
10586 if (necbs == 0) {
10587 ASSERT(oecbs == NULL);
10588 necbs = 1;
10589 }
10590
10591 ecbs = kmem_zalloc(necbs * sizeof (*ecbs), KM_SLEEP);
10592
10593 if (oecbs != NULL)
10594 bcopy(oecbs, ecbs, state->dts_necbs * sizeof (*ecbs));
10595
10596 dtrace_membar_producer();
10597 state->dts_ecbs = ecbs;
10598
10599 if (oecbs != NULL) {
10600 /*
10601 * If this state is active, we must dtrace_sync()
10602 * before we can free the old dts_ecbs array: we're
10603 * coming in hot, and there may be active ring
10604 * buffer processing (which indexes into the dts_ecbs
10605 * array) on another CPU.
10606 */
10607 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
10608 dtrace_sync();
10609
10610 kmem_free(oecbs, state->dts_necbs * sizeof (*ecbs));
10611 }
10612
10613 dtrace_membar_producer();
10614 state->dts_necbs = necbs;
10615 }
10616
10617 ecb->dte_state = state;
10618
10619 ASSERT(state->dts_ecbs[epid - 1] == NULL);
10620 dtrace_membar_producer();
10621 state->dts_ecbs[(ecb->dte_epid = epid) - 1] = ecb;
10622
10623 return (ecb);
10624 }
10625
10626 static int
10627 dtrace_ecb_enable(dtrace_ecb_t *ecb)
10628 {
10629 dtrace_probe_t *probe = ecb->dte_probe;
10630
10631 ASSERT(MUTEX_HELD(&cpu_lock));
10632 ASSERT(MUTEX_HELD(&dtrace_lock));
10633 ASSERT(ecb->dte_next == NULL);
10634
10635 if (probe == NULL) {
10636 /*
10637 * This is the NULL probe -- there's nothing to do.
10638 */
10639 return (0);
10640 }
10641
10642 if (probe->dtpr_ecb == NULL) {
10643 dtrace_provider_t *prov = probe->dtpr_provider;
10644
10645 /*
10646 * We're the first ECB on this probe.
10647 */
10648 probe->dtpr_ecb = probe->dtpr_ecb_last = ecb;
10649
10650 if (ecb->dte_predicate != NULL)
10651 probe->dtpr_predcache = ecb->dte_predicate->dtp_cacheid;
10652
10653 return (prov->dtpv_pops.dtps_enable(prov->dtpv_arg,
10654 probe->dtpr_id, probe->dtpr_arg));
10655 } else {
10656 /*
10657 * This probe is already active. Swing the last pointer to
10658 * point to the new ECB, and issue a dtrace_sync() to assure
10659 * that all CPUs have seen the change.
10660 */
10661 ASSERT(probe->dtpr_ecb_last != NULL);
10662 probe->dtpr_ecb_last->dte_next = ecb;
10663 probe->dtpr_ecb_last = ecb;
10664 probe->dtpr_predcache = 0;
10665
10666 dtrace_sync();
10667 return (0);
10668 }
10669 }
10670
10671 static int
10672 dtrace_ecb_resize(dtrace_ecb_t *ecb)
10673 {
10674 dtrace_action_t *act;
10675 uint32_t curneeded = UINT32_MAX;
10676 uint32_t aggbase = UINT32_MAX;
10677
10678 /*
10679 * If we record anything, we always record the dtrace_rechdr_t. (And
10680 * we always record it first.)
10681 */
10682 ecb->dte_size = sizeof (dtrace_rechdr_t);
10683 ecb->dte_alignment = sizeof (dtrace_epid_t);
10684
10685 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
10686 dtrace_recdesc_t *rec = &act->dta_rec;
10687 ASSERT(rec->dtrd_size > 0 || rec->dtrd_alignment == 1);
10688
10689 ecb->dte_alignment = MAX(ecb->dte_alignment,
10690 rec->dtrd_alignment);
10691
10692 if (DTRACEACT_ISAGG(act->dta_kind)) {
10693 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
10694
10695 ASSERT(rec->dtrd_size != 0);
10696 ASSERT(agg->dtag_first != NULL);
10697 ASSERT(act->dta_prev->dta_intuple);
10698 ASSERT(aggbase != UINT32_MAX);
10699 ASSERT(curneeded != UINT32_MAX);
10700
10701 agg->dtag_base = aggbase;
10702
10703 curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment);
10704 rec->dtrd_offset = curneeded;
10705 if (curneeded + rec->dtrd_size < curneeded)
10706 return (EINVAL);
10707 curneeded += rec->dtrd_size;
10708 ecb->dte_needed = MAX(ecb->dte_needed, curneeded);
10709
10710 aggbase = UINT32_MAX;
10711 curneeded = UINT32_MAX;
10712 } else if (act->dta_intuple) {
10713 if (curneeded == UINT32_MAX) {
10714 /*
10715 * This is the first record in a tuple. Align
10716 * curneeded to be at offset 4 in an 8-byte
10717 * aligned block.
10718 */
10719 ASSERT(act->dta_prev == NULL ||
10720 !act->dta_prev->dta_intuple);
10721 ASSERT3U(aggbase, ==, UINT32_MAX);
10722 curneeded = P2PHASEUP(ecb->dte_size,
10723 sizeof (uint64_t), sizeof (dtrace_aggid_t));
10724
10725 aggbase = curneeded - sizeof (dtrace_aggid_t);
10726 ASSERT(IS_P2ALIGNED(aggbase,
10727 sizeof (uint64_t)));
10728 }
10729 curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment);
10730 rec->dtrd_offset = curneeded;
10731 if (curneeded + rec->dtrd_size < curneeded)
10732 return (EINVAL);
10733 curneeded += rec->dtrd_size;
10734 } else {
10735 /* tuples must be followed by an aggregation */
10736 ASSERT(act->dta_prev == NULL ||
10737 !act->dta_prev->dta_intuple);
10738
10739 ecb->dte_size = P2ROUNDUP(ecb->dte_size,
10740 rec->dtrd_alignment);
10741 rec->dtrd_offset = ecb->dte_size;
10742 if (ecb->dte_size + rec->dtrd_size < ecb->dte_size)
10743 return (EINVAL);
10744 ecb->dte_size += rec->dtrd_size;
10745 ecb->dte_needed = MAX(ecb->dte_needed, ecb->dte_size);
10746 }
10747 }
10748
10749 if ((act = ecb->dte_action) != NULL &&
10750 !(act->dta_kind == DTRACEACT_SPECULATE && act->dta_next == NULL) &&
10751 ecb->dte_size == sizeof (dtrace_rechdr_t)) {
10752 /*
10753 * If the size is still sizeof (dtrace_rechdr_t), then all
10754 * actions store no data; set the size to 0.
10755 */
10756 ecb->dte_size = 0;
10757 }
10758
10759 ecb->dte_size = P2ROUNDUP(ecb->dte_size, sizeof (dtrace_epid_t));
10760 ecb->dte_needed = P2ROUNDUP(ecb->dte_needed, (sizeof (dtrace_epid_t)));
10761 ecb->dte_state->dts_needed = MAX(ecb->dte_state->dts_needed,
10762 ecb->dte_needed);
10763 return (0);
10764 }
10765
10766 static dtrace_action_t *
10767 dtrace_ecb_aggregation_create(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
10768 {
10769 dtrace_aggregation_t *agg;
10770 size_t size = sizeof (uint64_t);
10771 int ntuple = desc->dtad_ntuple;
10772 dtrace_action_t *act;
10773 dtrace_recdesc_t *frec;
10774 dtrace_aggid_t aggid;
10775 dtrace_state_t *state = ecb->dte_state;
10776
10777 agg = kmem_zalloc(sizeof (dtrace_aggregation_t), KM_SLEEP);
10778 agg->dtag_ecb = ecb;
10779
10780 ASSERT(DTRACEACT_ISAGG(desc->dtad_kind));
10781
10782 switch (desc->dtad_kind) {
10783 case DTRACEAGG_MIN:
10784 agg->dtag_initial = INT64_MAX;
10785 agg->dtag_aggregate = dtrace_aggregate_min;
10786 break;
10787
10788 case DTRACEAGG_MAX:
10789 agg->dtag_initial = INT64_MIN;
10790 agg->dtag_aggregate = dtrace_aggregate_max;
10791 break;
10792
10793 case DTRACEAGG_COUNT:
10794 agg->dtag_aggregate = dtrace_aggregate_count;
10795 break;
10796
10797 case DTRACEAGG_QUANTIZE:
10798 agg->dtag_aggregate = dtrace_aggregate_quantize;
10799 size = (((sizeof (uint64_t) * NBBY) - 1) * 2 + 1) *
10800 sizeof (uint64_t);
10801 break;
10802
10803 case DTRACEAGG_LQUANTIZE: {
10804 uint16_t step = DTRACE_LQUANTIZE_STEP(desc->dtad_arg);
10805 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(desc->dtad_arg);
10806
10807 agg->dtag_initial = desc->dtad_arg;
10808 agg->dtag_aggregate = dtrace_aggregate_lquantize;
10809
10810 if (step == 0 || levels == 0)
10811 goto err;
10812
10813 size = levels * sizeof (uint64_t) + 3 * sizeof (uint64_t);
10814 break;
10815 }
10816
10817 case DTRACEAGG_LLQUANTIZE: {
10818 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(desc->dtad_arg);
10819 uint16_t low = DTRACE_LLQUANTIZE_LOW(desc->dtad_arg);
10820 uint16_t high = DTRACE_LLQUANTIZE_HIGH(desc->dtad_arg);
10821 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(desc->dtad_arg);
10822 int64_t v;
10823
10824 agg->dtag_initial = desc->dtad_arg;
10825 agg->dtag_aggregate = dtrace_aggregate_llquantize;
10826
10827 if (factor < 2 || low >= high || nsteps < factor)
10828 goto err;
10829
10830 /*
10831 * Now check that the number of steps evenly divides a power
10832 * of the factor. (This assures both integer bucket size and
10833 * linearity within each magnitude.)
10834 */
10835 for (v = factor; v < nsteps; v *= factor)
10836 continue;
10837
10838 if ((v % nsteps) || (nsteps % factor))
10839 goto err;
10840
10841 size = (dtrace_aggregate_llquantize_bucket(factor,
10842 low, high, nsteps, INT64_MAX) + 2) * sizeof (uint64_t);
10843 break;
10844 }
10845
10846 case DTRACEAGG_AVG:
10847 agg->dtag_aggregate = dtrace_aggregate_avg;
10848 size = sizeof (uint64_t) * 2;
10849 break;
10850
10851 case DTRACEAGG_STDDEV:
10852 agg->dtag_aggregate = dtrace_aggregate_stddev;
10853 size = sizeof (uint64_t) * 4;
10854 break;
10855
10856 case DTRACEAGG_SUM:
10857 agg->dtag_aggregate = dtrace_aggregate_sum;
10858 break;
10859
10860 default:
10861 goto err;
10862 }
10863
10864 agg->dtag_action.dta_rec.dtrd_size = size;
10865
10866 if (ntuple == 0)
10867 goto err;
10868
10869 /*
10870 * We must make sure that we have enough actions for the n-tuple.
10871 */
10872 for (act = ecb->dte_action_last; act != NULL; act = act->dta_prev) {
10873 if (DTRACEACT_ISAGG(act->dta_kind))
10874 break;
10875
10876 if (--ntuple == 0) {
10877 /*
10878 * This is the action with which our n-tuple begins.
10879 */
10880 agg->dtag_first = act;
10881 goto success;
10882 }
10883 }
10884
10885 /*
10886 * This n-tuple is short by ntuple elements. Return failure.
10887 */
10888 ASSERT(ntuple != 0);
10889 err:
10890 kmem_free(agg, sizeof (dtrace_aggregation_t));
10891 return (NULL);
10892
10893 success:
10894 /*
10895 * If the last action in the tuple has a size of zero, it's actually
10896 * an expression argument for the aggregating action.
10897 */
10898 ASSERT(ecb->dte_action_last != NULL);
10899 act = ecb->dte_action_last;
10900
10901 if (act->dta_kind == DTRACEACT_DIFEXPR) {
10902 ASSERT(act->dta_difo != NULL);
10903
10904 if (act->dta_difo->dtdo_rtype.dtdt_size == 0)
10905 agg->dtag_hasarg = 1;
10906 }
10907
10908 /*
10909 * We need to allocate an id for this aggregation.
10910 */
10911 aggid = (dtrace_aggid_t)(uintptr_t)vmem_alloc(state->dts_aggid_arena, 1,
10912 VM_BESTFIT | VM_SLEEP);
10913
10914 if (aggid - 1 >= state->dts_naggregations) {
10915 dtrace_aggregation_t **oaggs = state->dts_aggregations;
10916 dtrace_aggregation_t **aggs;
10917 int naggs = state->dts_naggregations << 1;
10918 int onaggs = state->dts_naggregations;
10919
10920 ASSERT(aggid == state->dts_naggregations + 1);
10921
10922 if (naggs == 0) {
10923 ASSERT(oaggs == NULL);
10924 naggs = 1;
10925 }
10926
10927 aggs = kmem_zalloc(naggs * sizeof (*aggs), KM_SLEEP);
10928
10929 if (oaggs != NULL) {
10930 bcopy(oaggs, aggs, onaggs * sizeof (*aggs));
10931 kmem_free(oaggs, onaggs * sizeof (*aggs));
10932 }
10933
10934 state->dts_aggregations = aggs;
10935 state->dts_naggregations = naggs;
10936 }
10937
10938 ASSERT(state->dts_aggregations[aggid - 1] == NULL);
10939 state->dts_aggregations[(agg->dtag_id = aggid) - 1] = agg;
10940
10941 frec = &agg->dtag_first->dta_rec;
10942 if (frec->dtrd_alignment < sizeof (dtrace_aggid_t))
10943 frec->dtrd_alignment = sizeof (dtrace_aggid_t);
10944
10945 for (act = agg->dtag_first; act != NULL; act = act->dta_next) {
10946 ASSERT(!act->dta_intuple);
10947 act->dta_intuple = 1;
10948 }
10949
10950 return (&agg->dtag_action);
10951 }
10952
10953 static void
10954 dtrace_ecb_aggregation_destroy(dtrace_ecb_t *ecb, dtrace_action_t *act)
10955 {
10956 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
10957 dtrace_state_t *state = ecb->dte_state;
10958 dtrace_aggid_t aggid = agg->dtag_id;
10959
10960 ASSERT(DTRACEACT_ISAGG(act->dta_kind));
10961 vmem_free(state->dts_aggid_arena, (void *)(uintptr_t)aggid, 1);
10962
10963 ASSERT(state->dts_aggregations[aggid - 1] == agg);
10964 state->dts_aggregations[aggid - 1] = NULL;
10965
10966 kmem_free(agg, sizeof (dtrace_aggregation_t));
10967 }
10968
10969 static int
10970 dtrace_ecb_action_add(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
10971 {
10972 dtrace_action_t *action, *last;
10973 dtrace_difo_t *dp = desc->dtad_difo;
10974 uint32_t size = 0, align = sizeof (uint8_t), mask;
10975 uint16_t format = 0;
10976 dtrace_recdesc_t *rec;
10977 dtrace_state_t *state = ecb->dte_state;
10978 dtrace_optval_t *opt = state->dts_options, nframes, strsize;
10979 uint64_t arg = desc->dtad_arg;
10980
10981 ASSERT(MUTEX_HELD(&dtrace_lock));
10982 ASSERT(ecb->dte_action == NULL || ecb->dte_action->dta_refcnt == 1);
10983
10984 if (DTRACEACT_ISAGG(desc->dtad_kind)) {
10985 /*
10986 * If this is an aggregating action, there must be neither
10987 * a speculate nor a commit on the action chain.
10988 */
10989 dtrace_action_t *act;
10990
10991 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
10992 if (act->dta_kind == DTRACEACT_COMMIT)
10993 return (EINVAL);
10994
10995 if (act->dta_kind == DTRACEACT_SPECULATE)
10996 return (EINVAL);
10997 }
10998
10999 action = dtrace_ecb_aggregation_create(ecb, desc);
11000
11001 if (action == NULL)
11002 return (EINVAL);
11003 } else {
11004 if (DTRACEACT_ISDESTRUCTIVE(desc->dtad_kind) ||
11005 (desc->dtad_kind == DTRACEACT_DIFEXPR &&
11006 dp != NULL && dp->dtdo_destructive)) {
11007 state->dts_destructive = 1;
11008 }
11009
11010 switch (desc->dtad_kind) {
11011 case DTRACEACT_PRINTF:
11012 case DTRACEACT_PRINTA:
11013 case DTRACEACT_SYSTEM:
11014 case DTRACEACT_FREOPEN:
11015 case DTRACEACT_DIFEXPR:
11016 /*
11017 * We know that our arg is a string -- turn it into a
11018 * format.
11019 */
11020 if (arg == 0) {
11021 ASSERT(desc->dtad_kind == DTRACEACT_PRINTA ||
11022 desc->dtad_kind == DTRACEACT_DIFEXPR);
11023 format = 0;
11024 } else {
11025 ASSERT(arg != 0);
11026 ASSERT(arg > KERNELBASE);
11027 format = dtrace_format_add(state,
11028 (char *)(uintptr_t)arg);
11029 }
11030
11031 /*FALLTHROUGH*/
11032 case DTRACEACT_LIBACT:
11033 case DTRACEACT_TRACEMEM:
11034 case DTRACEACT_TRACEMEM_DYNSIZE:
11035 if (dp == NULL)
11036 return (EINVAL);
11037
11038 if ((size = dp->dtdo_rtype.dtdt_size) != 0)
11039 break;
11040
11041 if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) {
11042 if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11043 return (EINVAL);
11044
11045 size = opt[DTRACEOPT_STRSIZE];
11046 }
11047
11048 break;
11049
11050 case DTRACEACT_STACK:
11051 if ((nframes = arg) == 0) {
11052 nframes = opt[DTRACEOPT_STACKFRAMES];
11053 ASSERT(nframes > 0);
11054 arg = nframes;
11055 }
11056
11057 size = nframes * sizeof (pc_t);
11058 break;
11059
11060 case DTRACEACT_JSTACK:
11061 if ((strsize = DTRACE_USTACK_STRSIZE(arg)) == 0)
11062 strsize = opt[DTRACEOPT_JSTACKSTRSIZE];
11063
11064 if ((nframes = DTRACE_USTACK_NFRAMES(arg)) == 0)
11065 nframes = opt[DTRACEOPT_JSTACKFRAMES];
11066
11067 arg = DTRACE_USTACK_ARG(nframes, strsize);
11068
11069 /*FALLTHROUGH*/
11070 case DTRACEACT_USTACK:
11071 if (desc->dtad_kind != DTRACEACT_JSTACK &&
11072 (nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) {
11073 strsize = DTRACE_USTACK_STRSIZE(arg);
11074 nframes = opt[DTRACEOPT_USTACKFRAMES];
11075 ASSERT(nframes > 0);
11076 arg = DTRACE_USTACK_ARG(nframes, strsize);
11077 }
11078
11079 /*
11080 * Save a slot for the pid.
11081 */
11082 size = (nframes + 1) * sizeof (uint64_t);
11083 size += DTRACE_USTACK_STRSIZE(arg);
11084 size = P2ROUNDUP(size, (uint32_t)(sizeof (uintptr_t)));
11085
11086 break;
11087
11088 case DTRACEACT_SYM:
11089 case DTRACEACT_MOD:
11090 if (dp == NULL || ((size = dp->dtdo_rtype.dtdt_size) !=
11091 sizeof (uint64_t)) ||
11092 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11093 return (EINVAL);
11094 break;
11095
11096 case DTRACEACT_USYM:
11097 case DTRACEACT_UMOD:
11098 case DTRACEACT_UADDR:
11099 if (dp == NULL ||
11100 (dp->dtdo_rtype.dtdt_size != sizeof (uint64_t)) ||
11101 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11102 return (EINVAL);
11103
11104 /*
11105 * We have a slot for the pid, plus a slot for the
11106 * argument. To keep things simple (aligned with
11107 * bitness-neutral sizing), we store each as a 64-bit
11108 * quantity.
11109 */
11110 size = 2 * sizeof (uint64_t);
11111 break;
11112
11113 case DTRACEACT_STOP:
11114 case DTRACEACT_BREAKPOINT:
11115 case DTRACEACT_PANIC:
11116 break;
11117
11118 case DTRACEACT_CHILL:
11119 case DTRACEACT_DISCARD:
11120 case DTRACEACT_RAISE:
11121 if (dp == NULL)
11122 return (EINVAL);
11123 break;
11124
11125 case DTRACEACT_EXIT:
11126 if (dp == NULL ||
11127 (size = dp->dtdo_rtype.dtdt_size) != sizeof (int) ||
11128 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11129 return (EINVAL);
11130 break;
11131
11132 case DTRACEACT_SPECULATE:
11133 if (ecb->dte_size > sizeof (dtrace_rechdr_t))
11134 return (EINVAL);
11135
11136 if (dp == NULL)
11137 return (EINVAL);
11138
11139 state->dts_speculates = 1;
11140 break;
11141
11142 case DTRACEACT_COMMIT: {
11143 dtrace_action_t *act = ecb->dte_action;
11144
11145 for (; act != NULL; act = act->dta_next) {
11146 if (act->dta_kind == DTRACEACT_COMMIT)
11147 return (EINVAL);
11148 }
11149
11150 if (dp == NULL)
11151 return (EINVAL);
11152 break;
11153 }
11154
11155 default:
11156 return (EINVAL);
11157 }
11158
11159 if (size != 0 || desc->dtad_kind == DTRACEACT_SPECULATE) {
11160 /*
11161 * If this is a data-storing action or a speculate,
11162 * we must be sure that there isn't a commit on the
11163 * action chain.
11164 */
11165 dtrace_action_t *act = ecb->dte_action;
11166
11167 for (; act != NULL; act = act->dta_next) {
11168 if (act->dta_kind == DTRACEACT_COMMIT)
11169 return (EINVAL);
11170 }
11171 }
11172
11173 action = kmem_zalloc(sizeof (dtrace_action_t), KM_SLEEP);
11174 action->dta_rec.dtrd_size = size;
11175 }
11176
11177 action->dta_refcnt = 1;
11178 rec = &action->dta_rec;
11179 size = rec->dtrd_size;
11180
11181 for (mask = sizeof (uint64_t) - 1; size != 0 && mask > 0; mask >>= 1) {
11182 if (!(size & mask)) {
11183 align = mask + 1;
11184 break;
11185 }
11186 }
11187
11188 action->dta_kind = desc->dtad_kind;
11189
11190 if ((action->dta_difo = dp) != NULL)
11191 dtrace_difo_hold(dp);
11192
11193 rec->dtrd_action = action->dta_kind;
11194 rec->dtrd_arg = arg;
11195 rec->dtrd_uarg = desc->dtad_uarg;
11196 rec->dtrd_alignment = (uint16_t)align;
11197 rec->dtrd_format = format;
11198
11199 if ((last = ecb->dte_action_last) != NULL) {
11200 ASSERT(ecb->dte_action != NULL);
11201 action->dta_prev = last;
11202 last->dta_next = action;
11203 } else {
11204 ASSERT(ecb->dte_action == NULL);
11205 ecb->dte_action = action;
11206 }
11207
11208 ecb->dte_action_last = action;
11209
11210 return (0);
11211 }
11212
11213 static void
11214 dtrace_ecb_action_remove(dtrace_ecb_t *ecb)
11215 {
11216 dtrace_action_t *act = ecb->dte_action, *next;
11217 dtrace_vstate_t *vstate = &ecb->dte_state->dts_vstate;
11218 dtrace_difo_t *dp;
11219 uint16_t format;
11220
11221 if (act != NULL && act->dta_refcnt > 1) {
11222 ASSERT(act->dta_next == NULL || act->dta_next->dta_refcnt == 1);
11223 act->dta_refcnt--;
11224 } else {
11225 for (; act != NULL; act = next) {
11226 next = act->dta_next;
11227 ASSERT(next != NULL || act == ecb->dte_action_last);
11228 ASSERT(act->dta_refcnt == 1);
11229
11230 if ((format = act->dta_rec.dtrd_format) != 0)
11231 dtrace_format_remove(ecb->dte_state, format);
11232
11233 if ((dp = act->dta_difo) != NULL)
11234 dtrace_difo_release(dp, vstate);
11235
11236 if (DTRACEACT_ISAGG(act->dta_kind)) {
11237 dtrace_ecb_aggregation_destroy(ecb, act);
11238 } else {
11239 kmem_free(act, sizeof (dtrace_action_t));
11240 }
11241 }
11242 }
11243
11244 ecb->dte_action = NULL;
11245 ecb->dte_action_last = NULL;
11246 ecb->dte_size = 0;
11247 }
11248
11249 static void
11250 dtrace_ecb_disable(dtrace_ecb_t *ecb)
11251 {
11252 /*
11253 * We disable the ECB by removing it from its probe.
11254 */
11255 dtrace_ecb_t *pecb, *prev = NULL;
11256 dtrace_probe_t *probe = ecb->dte_probe;
11257
11258 ASSERT(MUTEX_HELD(&dtrace_lock));
11259
11260 if (probe == NULL) {
11261 /*
11262 * This is the NULL probe; there is nothing to disable.
11263 */
11264 return;
11265 }
11266
11267 for (pecb = probe->dtpr_ecb; pecb != NULL; pecb = pecb->dte_next) {
11268 if (pecb == ecb)
11269 break;
11270 prev = pecb;
11271 }
11272
11273 ASSERT(pecb != NULL);
11274
11275 if (prev == NULL) {
11276 probe->dtpr_ecb = ecb->dte_next;
11277 } else {
11278 prev->dte_next = ecb->dte_next;
11279 }
11280
11281 if (ecb == probe->dtpr_ecb_last) {
11282 ASSERT(ecb->dte_next == NULL);
11283 probe->dtpr_ecb_last = prev;
11284 }
11285
11286 /*
11287 * The ECB has been disconnected from the probe; now sync to assure
11288 * that all CPUs have seen the change before returning.
11289 */
11290 dtrace_sync();
11291
11292 if (probe->dtpr_ecb == NULL) {
11293 /*
11294 * That was the last ECB on the probe; clear the predicate
11295 * cache ID for the probe, disable it and sync one more time
11296 * to assure that we'll never hit it again.
11297 */
11298 dtrace_provider_t *prov = probe->dtpr_provider;
11299
11300 ASSERT(ecb->dte_next == NULL);
11301 ASSERT(probe->dtpr_ecb_last == NULL);
11302 probe->dtpr_predcache = DTRACE_CACHEIDNONE;
11303 prov->dtpv_pops.dtps_disable(prov->dtpv_arg,
11304 probe->dtpr_id, probe->dtpr_arg);
11305 dtrace_sync();
11306 } else {
11307 /*
11308 * There is at least one ECB remaining on the probe. If there
11309 * is _exactly_ one, set the probe's predicate cache ID to be
11310 * the predicate cache ID of the remaining ECB.
11311 */
11312 ASSERT(probe->dtpr_ecb_last != NULL);
11313 ASSERT(probe->dtpr_predcache == DTRACE_CACHEIDNONE);
11314
11315 if (probe->dtpr_ecb == probe->dtpr_ecb_last) {
11316 dtrace_predicate_t *p = probe->dtpr_ecb->dte_predicate;
11317
11318 ASSERT(probe->dtpr_ecb->dte_next == NULL);
11319
11320 if (p != NULL)
11321 probe->dtpr_predcache = p->dtp_cacheid;
11322 }
11323
11324 ecb->dte_next = NULL;
11325 }
11326 }
11327
11328 static void
11329 dtrace_ecb_destroy(dtrace_ecb_t *ecb)
11330 {
11331 dtrace_state_t *state = ecb->dte_state;
11332 dtrace_vstate_t *vstate = &state->dts_vstate;
11333 dtrace_predicate_t *pred;
11334 dtrace_epid_t epid = ecb->dte_epid;
11335
11336 ASSERT(MUTEX_HELD(&dtrace_lock));
11337 ASSERT(ecb->dte_next == NULL);
11338 ASSERT(ecb->dte_probe == NULL || ecb->dte_probe->dtpr_ecb != ecb);
11339
11340 if ((pred = ecb->dte_predicate) != NULL)
11341 dtrace_predicate_release(pred, vstate);
11342
11343 dtrace_ecb_action_remove(ecb);
11344
11345 ASSERT(state->dts_ecbs[epid - 1] == ecb);
11346 state->dts_ecbs[epid - 1] = NULL;
11347
11348 kmem_free(ecb, sizeof (dtrace_ecb_t));
11349 }
11350
11351 static dtrace_ecb_t *
11352 dtrace_ecb_create(dtrace_state_t *state, dtrace_probe_t *probe,
11353 dtrace_enabling_t *enab)
11354 {
11355 dtrace_ecb_t *ecb;
11356 dtrace_predicate_t *pred;
11357 dtrace_actdesc_t *act;
11358 dtrace_provider_t *prov;
11359 dtrace_ecbdesc_t *desc = enab->dten_current;
11360
11361 ASSERT(MUTEX_HELD(&dtrace_lock));
11362 ASSERT(state != NULL);
11363
11364 ecb = dtrace_ecb_add(state, probe);
11365 ecb->dte_uarg = desc->dted_uarg;
11366
11367 if ((pred = desc->dted_pred.dtpdd_predicate) != NULL) {
11368 dtrace_predicate_hold(pred);
11369 ecb->dte_predicate = pred;
11370 }
11371
11372 if (probe != NULL) {
11373 /*
11374 * If the provider shows more leg than the consumer is old
11375 * enough to see, we need to enable the appropriate implicit
11376 * predicate bits to prevent the ecb from activating at
11377 * revealing times.
11378 *
11379 * Providers specifying DTRACE_PRIV_USER at register time
11380 * are stating that they need the /proc-style privilege
11381 * model to be enforced, and this is what DTRACE_COND_OWNER
11382 * and DTRACE_COND_ZONEOWNER will then do at probe time.
11383 */
11384 prov = probe->dtpr_provider;
11385 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLPROC) &&
11386 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
11387 ecb->dte_cond |= DTRACE_COND_OWNER;
11388
11389 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLZONE) &&
11390 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
11391 ecb->dte_cond |= DTRACE_COND_ZONEOWNER;
11392
11393 /*
11394 * If the provider shows us kernel innards and the user
11395 * is lacking sufficient privilege, enable the
11396 * DTRACE_COND_USERMODE implicit predicate.
11397 */
11398 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) &&
11399 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_KERNEL))
11400 ecb->dte_cond |= DTRACE_COND_USERMODE;
11401 }
11402
11403 if (dtrace_ecb_create_cache != NULL) {
11404 /*
11405 * If we have a cached ecb, we'll use its action list instead
11406 * of creating our own (saving both time and space).
11407 */
11408 dtrace_ecb_t *cached = dtrace_ecb_create_cache;
11409 dtrace_action_t *act = cached->dte_action;
11410
11411 if (act != NULL) {
11412 ASSERT(act->dta_refcnt > 0);
11413 act->dta_refcnt++;
11414 ecb->dte_action = act;
11415 ecb->dte_action_last = cached->dte_action_last;
11416 ecb->dte_needed = cached->dte_needed;
11417 ecb->dte_size = cached->dte_size;
11418 ecb->dte_alignment = cached->dte_alignment;
11419 }
11420
11421 return (ecb);
11422 }
11423
11424 for (act = desc->dted_action; act != NULL; act = act->dtad_next) {
11425 if ((enab->dten_error = dtrace_ecb_action_add(ecb, act)) != 0) {
11426 dtrace_ecb_destroy(ecb);
11427 return (NULL);
11428 }
11429 }
11430
11431 if ((enab->dten_error = dtrace_ecb_resize(ecb)) != 0) {
11432 dtrace_ecb_destroy(ecb);
11433 return (NULL);
11434 }
11435
11436 return (dtrace_ecb_create_cache = ecb);
11437 }
11438
11439 static int
11440 dtrace_ecb_create_enable(dtrace_probe_t *probe, void *arg)
11441 {
11442 dtrace_ecb_t *ecb;
11443 dtrace_enabling_t *enab = arg;
11444 dtrace_state_t *state = enab->dten_vstate->dtvs_state;
11445
11446 ASSERT(state != NULL);
11447
11448 if (probe != NULL && probe->dtpr_gen < enab->dten_probegen) {
11449 /*
11450 * This probe was created in a generation for which this
11451 * enabling has previously created ECBs; we don't want to
11452 * enable it again, so just kick out.
11453 */
11454 return (DTRACE_MATCH_NEXT);
11455 }
11456
11457 if ((ecb = dtrace_ecb_create(state, probe, enab)) == NULL)
11458 return (DTRACE_MATCH_DONE);
11459
11460 if (dtrace_ecb_enable(ecb) < 0)
11461 return (DTRACE_MATCH_FAIL);
11462
11463 return (DTRACE_MATCH_NEXT);
11464 }
11465
11466 static dtrace_ecb_t *
11467 dtrace_epid2ecb(dtrace_state_t *state, dtrace_epid_t id)
11468 {
11469 dtrace_ecb_t *ecb;
11470
11471 ASSERT(MUTEX_HELD(&dtrace_lock));
11472
11473 if (id == 0 || id > state->dts_necbs)
11474 return (NULL);
11475
11476 ASSERT(state->dts_necbs > 0 && state->dts_ecbs != NULL);
11477 ASSERT((ecb = state->dts_ecbs[id - 1]) == NULL || ecb->dte_epid == id);
11478
11479 return (state->dts_ecbs[id - 1]);
11480 }
11481
11482 static dtrace_aggregation_t *
11483 dtrace_aggid2agg(dtrace_state_t *state, dtrace_aggid_t id)
11484 {
11485 dtrace_aggregation_t *agg;
11486
11487 ASSERT(MUTEX_HELD(&dtrace_lock));
11488
11489 if (id == 0 || id > state->dts_naggregations)
11490 return (NULL);
11491
11492 ASSERT(state->dts_naggregations > 0 && state->dts_aggregations != NULL);
11493 ASSERT((agg = state->dts_aggregations[id - 1]) == NULL ||
11494 agg->dtag_id == id);
11495
11496 return (state->dts_aggregations[id - 1]);
11497 }
11498
11499 /*
11500 * DTrace Buffer Functions
11501 *
11502 * The following functions manipulate DTrace buffers. Most of these functions
11503 * are called in the context of establishing or processing consumer state;
11504 * exceptions are explicitly noted.
11505 */
11506
11507 /*
11508 * Note: called from cross call context. This function switches the two
11509 * buffers on a given CPU. The atomicity of this operation is assured by
11510 * disabling interrupts while the actual switch takes place; the disabling of
11511 * interrupts serializes the execution with any execution of dtrace_probe() on
11512 * the same CPU.
11513 */
11514 static void
11515 dtrace_buffer_switch(dtrace_buffer_t *buf)
11516 {
11517 caddr_t tomax = buf->dtb_tomax;
11518 caddr_t xamot = buf->dtb_xamot;
11519 dtrace_icookie_t cookie;
11520 hrtime_t now;
11521
11522 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
11523 ASSERT(!(buf->dtb_flags & DTRACEBUF_RING));
11524
11525 cookie = dtrace_interrupt_disable();
11526 now = dtrace_gethrtime();
11527 buf->dtb_tomax = xamot;
11528 buf->dtb_xamot = tomax;
11529 buf->dtb_xamot_drops = buf->dtb_drops;
11530 buf->dtb_xamot_offset = buf->dtb_offset;
11531 buf->dtb_xamot_errors = buf->dtb_errors;
11532 buf->dtb_xamot_flags = buf->dtb_flags;
11533 buf->dtb_offset = 0;
11534 buf->dtb_drops = 0;
11535 buf->dtb_errors = 0;
11536 buf->dtb_flags &= ~(DTRACEBUF_ERROR | DTRACEBUF_DROPPED);
11537 buf->dtb_interval = now - buf->dtb_switched;
11538 buf->dtb_switched = now;
11539 dtrace_interrupt_enable(cookie);
11540 }
11541
11542 /*
11543 * Note: called from cross call context. This function activates a buffer
11544 * on a CPU. As with dtrace_buffer_switch(), the atomicity of the operation
11545 * is guaranteed by the disabling of interrupts.
11546 */
11547 static void
11548 dtrace_buffer_activate(dtrace_state_t *state)
11549 {
11550 dtrace_buffer_t *buf;
11551 dtrace_icookie_t cookie = dtrace_interrupt_disable();
11552
11553 buf = &state->dts_buffer[CPU->cpu_id];
11554
11555 if (buf->dtb_tomax != NULL) {
11556 /*
11557 * We might like to assert that the buffer is marked inactive,
11558 * but this isn't necessarily true: the buffer for the CPU
11559 * that processes the BEGIN probe has its buffer activated
11560 * manually. In this case, we take the (harmless) action
11561 * re-clearing the bit INACTIVE bit.
11562 */
11563 buf->dtb_flags &= ~DTRACEBUF_INACTIVE;
11564 }
11565
11566 dtrace_interrupt_enable(cookie);
11567 }
11568
11569 static int
11570 dtrace_buffer_alloc(dtrace_buffer_t *bufs, size_t size, int flags,
11571 processorid_t cpu, int *factor)
11572 {
11573 cpu_t *cp;
11574 dtrace_buffer_t *buf;
11575 int allocated = 0, desired = 0;
11576
11577 ASSERT(MUTEX_HELD(&cpu_lock));
11578 ASSERT(MUTEX_HELD(&dtrace_lock));
11579
11580 *factor = 1;
11581
11582 if (size > dtrace_nonroot_maxsize &&
11583 !PRIV_POLICY_CHOICE(CRED(), PRIV_ALL, B_FALSE))
11584 return (EFBIG);
11585
11586 cp = cpu_list;
11587
11588 do {
11589 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
11590 continue;
11591
11592 buf = &bufs[cp->cpu_id];
11593
11594 /*
11595 * If there is already a buffer allocated for this CPU, it
11596 * is only possible that this is a DR event. In this case,
11597 * the buffer size must match our specified size.
11598 */
11599 if (buf->dtb_tomax != NULL) {
11600 ASSERT(buf->dtb_size == size);
11601 continue;
11602 }
11603
11604 ASSERT(buf->dtb_xamot == NULL);
11605
11606 if ((buf->dtb_tomax = kmem_zalloc(size,
11607 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
11608 goto err;
11609
11610 buf->dtb_size = size;
11611 buf->dtb_flags = flags;
11612 buf->dtb_offset = 0;
11613 buf->dtb_drops = 0;
11614
11615 if (flags & DTRACEBUF_NOSWITCH)
11616 continue;
11617
11618 if ((buf->dtb_xamot = kmem_zalloc(size,
11619 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
11620 goto err;
11621 } while ((cp = cp->cpu_next) != cpu_list);
11622
11623 return (0);
11624
11625 err:
11626 cp = cpu_list;
11627
11628 do {
11629 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
11630 continue;
11631
11632 buf = &bufs[cp->cpu_id];
11633 desired += 2;
11634
11635 if (buf->dtb_xamot != NULL) {
11636 ASSERT(buf->dtb_tomax != NULL);
11637 ASSERT(buf->dtb_size == size);
11638 kmem_free(buf->dtb_xamot, size);
11639 allocated++;
11640 }
11641
11642 if (buf->dtb_tomax != NULL) {
11643 ASSERT(buf->dtb_size == size);
11644 kmem_free(buf->dtb_tomax, size);
11645 allocated++;
11646 }
11647
11648 buf->dtb_tomax = NULL;
11649 buf->dtb_xamot = NULL;
11650 buf->dtb_size = 0;
11651 } while ((cp = cp->cpu_next) != cpu_list);
11652
11653 *factor = desired / (allocated > 0 ? allocated : 1);
11654
11655 return (ENOMEM);
11656 }
11657
11658 /*
11659 * Note: called from probe context. This function just increments the drop
11660 * count on a buffer. It has been made a function to allow for the
11661 * possibility of understanding the source of mysterious drop counts. (A
11662 * problem for which one may be particularly disappointed that DTrace cannot
11663 * be used to understand DTrace.)
11664 */
11665 static void
11666 dtrace_buffer_drop(dtrace_buffer_t *buf)
11667 {
11668 buf->dtb_drops++;
11669 }
11670
11671 /*
11672 * Note: called from probe context. This function is called to reserve space
11673 * in a buffer. If mstate is non-NULL, sets the scratch base and size in the
11674 * mstate. Returns the new offset in the buffer, or a negative value if an
11675 * error has occurred.
11676 */
11677 static intptr_t
11678 dtrace_buffer_reserve(dtrace_buffer_t *buf, size_t needed, size_t align,
11679 dtrace_state_t *state, dtrace_mstate_t *mstate)
11680 {
11681 intptr_t offs = buf->dtb_offset, soffs;
11682 intptr_t woffs;
11683 caddr_t tomax;
11684 size_t total;
11685
11686 if (buf->dtb_flags & DTRACEBUF_INACTIVE)
11687 return (-1);
11688
11689 if ((tomax = buf->dtb_tomax) == NULL) {
11690 dtrace_buffer_drop(buf);
11691 return (-1);
11692 }
11693
11694 if (!(buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL))) {
11695 while (offs & (align - 1)) {
11696 /*
11697 * Assert that our alignment is off by a number which
11698 * is itself sizeof (uint32_t) aligned.
11699 */
11700 ASSERT(!((align - (offs & (align - 1))) &
11701 (sizeof (uint32_t) - 1)));
11702 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
11703 offs += sizeof (uint32_t);
11704 }
11705
11706 if ((soffs = offs + needed) > buf->dtb_size) {
11707 dtrace_buffer_drop(buf);
11708 return (-1);
11709 }
11710
11711 if (mstate == NULL)
11712 return (offs);
11713
11714 mstate->dtms_scratch_base = (uintptr_t)tomax + soffs;
11715 mstate->dtms_scratch_size = buf->dtb_size - soffs;
11716 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
11717
11718 return (offs);
11719 }
11720
11721 if (buf->dtb_flags & DTRACEBUF_FILL) {
11722 if (state->dts_activity != DTRACE_ACTIVITY_COOLDOWN &&
11723 (buf->dtb_flags & DTRACEBUF_FULL))
11724 return (-1);
11725 goto out;
11726 }
11727
11728 total = needed + (offs & (align - 1));
11729
11730 /*
11731 * For a ring buffer, life is quite a bit more complicated. Before
11732 * we can store any padding, we need to adjust our wrapping offset.
11733 * (If we've never before wrapped or we're not about to, no adjustment
11734 * is required.)
11735 */
11736 if ((buf->dtb_flags & DTRACEBUF_WRAPPED) ||
11737 offs + total > buf->dtb_size) {
11738 woffs = buf->dtb_xamot_offset;
11739
11740 if (offs + total > buf->dtb_size) {
11741 /*
11742 * We can't fit in the end of the buffer. First, a
11743 * sanity check that we can fit in the buffer at all.
11744 */
11745 if (total > buf->dtb_size) {
11746 dtrace_buffer_drop(buf);
11747 return (-1);
11748 }
11749
11750 /*
11751 * We're going to be storing at the top of the buffer,
11752 * so now we need to deal with the wrapped offset. We
11753 * only reset our wrapped offset to 0 if it is
11754 * currently greater than the current offset. If it
11755 * is less than the current offset, it is because a
11756 * previous allocation induced a wrap -- but the
11757 * allocation didn't subsequently take the space due
11758 * to an error or false predicate evaluation. In this
11759 * case, we'll just leave the wrapped offset alone: if
11760 * the wrapped offset hasn't been advanced far enough
11761 * for this allocation, it will be adjusted in the
11762 * lower loop.
11763 */
11764 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
11765 if (woffs >= offs)
11766 woffs = 0;
11767 } else {
11768 woffs = 0;
11769 }
11770
11771 /*
11772 * Now we know that we're going to be storing to the
11773 * top of the buffer and that there is room for us
11774 * there. We need to clear the buffer from the current
11775 * offset to the end (there may be old gunk there).
11776 */
11777 while (offs < buf->dtb_size)
11778 tomax[offs++] = 0;
11779
11780 /*
11781 * We need to set our offset to zero. And because we
11782 * are wrapping, we need to set the bit indicating as
11783 * much. We can also adjust our needed space back
11784 * down to the space required by the ECB -- we know
11785 * that the top of the buffer is aligned.
11786 */
11787 offs = 0;
11788 total = needed;
11789 buf->dtb_flags |= DTRACEBUF_WRAPPED;
11790 } else {
11791 /*
11792 * There is room for us in the buffer, so we simply
11793 * need to check the wrapped offset.
11794 */
11795 if (woffs < offs) {
11796 /*
11797 * The wrapped offset is less than the offset.
11798 * This can happen if we allocated buffer space
11799 * that induced a wrap, but then we didn't
11800 * subsequently take the space due to an error
11801 * or false predicate evaluation. This is
11802 * okay; we know that _this_ allocation isn't
11803 * going to induce a wrap. We still can't
11804 * reset the wrapped offset to be zero,
11805 * however: the space may have been trashed in
11806 * the previous failed probe attempt. But at
11807 * least the wrapped offset doesn't need to
11808 * be adjusted at all...
11809 */
11810 goto out;
11811 }
11812 }
11813
11814 while (offs + total > woffs) {
11815 dtrace_epid_t epid = *(uint32_t *)(tomax + woffs);
11816 size_t size;
11817
11818 if (epid == DTRACE_EPIDNONE) {
11819 size = sizeof (uint32_t);
11820 } else {
11821 ASSERT3U(epid, <=, state->dts_necbs);
11822 ASSERT(state->dts_ecbs[epid - 1] != NULL);
11823
11824 size = state->dts_ecbs[epid - 1]->dte_size;
11825 }
11826
11827 ASSERT(woffs + size <= buf->dtb_size);
11828 ASSERT(size != 0);
11829
11830 if (woffs + size == buf->dtb_size) {
11831 /*
11832 * We've reached the end of the buffer; we want
11833 * to set the wrapped offset to 0 and break
11834 * out. However, if the offs is 0, then we're
11835 * in a strange edge-condition: the amount of
11836 * space that we want to reserve plus the size
11837 * of the record that we're overwriting is
11838 * greater than the size of the buffer. This
11839 * is problematic because if we reserve the
11840 * space but subsequently don't consume it (due
11841 * to a failed predicate or error) the wrapped
11842 * offset will be 0 -- yet the EPID at offset 0
11843 * will not be committed. This situation is
11844 * relatively easy to deal with: if we're in
11845 * this case, the buffer is indistinguishable
11846 * from one that hasn't wrapped; we need only
11847 * finish the job by clearing the wrapped bit,
11848 * explicitly setting the offset to be 0, and
11849 * zero'ing out the old data in the buffer.
11850 */
11851 if (offs == 0) {
11852 buf->dtb_flags &= ~DTRACEBUF_WRAPPED;
11853 buf->dtb_offset = 0;
11854 woffs = total;
11855
11856 while (woffs < buf->dtb_size)
11857 tomax[woffs++] = 0;
11858 }
11859
11860 woffs = 0;
11861 break;
11862 }
11863
11864 woffs += size;
11865 }
11866
11867 /*
11868 * We have a wrapped offset. It may be that the wrapped offset
11869 * has become zero -- that's okay.
11870 */
11871 buf->dtb_xamot_offset = woffs;
11872 }
11873
11874 out:
11875 /*
11876 * Now we can plow the buffer with any necessary padding.
11877 */
11878 while (offs & (align - 1)) {
11879 /*
11880 * Assert that our alignment is off by a number which
11881 * is itself sizeof (uint32_t) aligned.
11882 */
11883 ASSERT(!((align - (offs & (align - 1))) &
11884 (sizeof (uint32_t) - 1)));
11885 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
11886 offs += sizeof (uint32_t);
11887 }
11888
11889 if (buf->dtb_flags & DTRACEBUF_FILL) {
11890 if (offs + needed > buf->dtb_size - state->dts_reserve) {
11891 buf->dtb_flags |= DTRACEBUF_FULL;
11892 return (-1);
11893 }
11894 }
11895
11896 if (mstate == NULL)
11897 return (offs);
11898
11899 /*
11900 * For ring buffers and fill buffers, the scratch space is always
11901 * the inactive buffer.
11902 */
11903 mstate->dtms_scratch_base = (uintptr_t)buf->dtb_xamot;
11904 mstate->dtms_scratch_size = buf->dtb_size;
11905 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
11906
11907 return (offs);
11908 }
11909
11910 static void
11911 dtrace_buffer_polish(dtrace_buffer_t *buf)
11912 {
11913 ASSERT(buf->dtb_flags & DTRACEBUF_RING);
11914 ASSERT(MUTEX_HELD(&dtrace_lock));
11915
11916 if (!(buf->dtb_flags & DTRACEBUF_WRAPPED))
11917 return;
11918
11919 /*
11920 * We need to polish the ring buffer. There are three cases:
11921 *
11922 * - The first (and presumably most common) is that there is no gap
11923 * between the buffer offset and the wrapped offset. In this case,
11924 * there is nothing in the buffer that isn't valid data; we can
11925 * mark the buffer as polished and return.
11926 *
11927 * - The second (less common than the first but still more common
11928 * than the third) is that there is a gap between the buffer offset
11929 * and the wrapped offset, and the wrapped offset is larger than the
11930 * buffer offset. This can happen because of an alignment issue, or
11931 * can happen because of a call to dtrace_buffer_reserve() that
11932 * didn't subsequently consume the buffer space. In this case,
11933 * we need to zero the data from the buffer offset to the wrapped
11934 * offset.
11935 *
11936 * - The third (and least common) is that there is a gap between the
11937 * buffer offset and the wrapped offset, but the wrapped offset is
11938 * _less_ than the buffer offset. This can only happen because a
11939 * call to dtrace_buffer_reserve() induced a wrap, but the space
11940 * was not subsequently consumed. In this case, we need to zero the
11941 * space from the offset to the end of the buffer _and_ from the
11942 * top of the buffer to the wrapped offset.
11943 */
11944 if (buf->dtb_offset < buf->dtb_xamot_offset) {
11945 bzero(buf->dtb_tomax + buf->dtb_offset,
11946 buf->dtb_xamot_offset - buf->dtb_offset);
11947 }
11948
11949 if (buf->dtb_offset > buf->dtb_xamot_offset) {
11950 bzero(buf->dtb_tomax + buf->dtb_offset,
11951 buf->dtb_size - buf->dtb_offset);
11952 bzero(buf->dtb_tomax, buf->dtb_xamot_offset);
11953 }
11954 }
11955
11956 /*
11957 * This routine determines if data generated at the specified time has likely
11958 * been entirely consumed at user-level. This routine is called to determine
11959 * if an ECB on a defunct probe (but for an active enabling) can be safely
11960 * disabled and destroyed.
11961 */
11962 static int
11963 dtrace_buffer_consumed(dtrace_buffer_t *bufs, hrtime_t when)
11964 {
11965 int i;
11966
11967 for (i = 0; i < NCPU; i++) {
11968 dtrace_buffer_t *buf = &bufs[i];
11969
11970 if (buf->dtb_size == 0)
11971 continue;
11972
11973 if (buf->dtb_flags & DTRACEBUF_RING)
11974 return (0);
11975
11976 if (!buf->dtb_switched && buf->dtb_offset != 0)
11977 return (0);
11978
11979 if (buf->dtb_switched - buf->dtb_interval < when)
11980 return (0);
11981 }
11982
11983 return (1);
11984 }
11985
11986 static void
11987 dtrace_buffer_free(dtrace_buffer_t *bufs)
11988 {
11989 int i;
11990
11991 for (i = 0; i < NCPU; i++) {
11992 dtrace_buffer_t *buf = &bufs[i];
11993
11994 if (buf->dtb_tomax == NULL) {
11995 ASSERT(buf->dtb_xamot == NULL);
11996 ASSERT(buf->dtb_size == 0);
11997 continue;
11998 }
11999
12000 if (buf->dtb_xamot != NULL) {
12001 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
12002 kmem_free(buf->dtb_xamot, buf->dtb_size);
12003 }
12004
12005 kmem_free(buf->dtb_tomax, buf->dtb_size);
12006 buf->dtb_size = 0;
12007 buf->dtb_tomax = NULL;
12008 buf->dtb_xamot = NULL;
12009 }
12010 }
12011
12012 /*
12013 * DTrace Enabling Functions
12014 */
12015 static dtrace_enabling_t *
12016 dtrace_enabling_create(dtrace_vstate_t *vstate)
12017 {
12018 dtrace_enabling_t *enab;
12019
12020 enab = kmem_zalloc(sizeof (dtrace_enabling_t), KM_SLEEP);
12021 enab->dten_vstate = vstate;
12022
12023 return (enab);
12024 }
12025
12026 static void
12027 dtrace_enabling_add(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb)
12028 {
12029 dtrace_ecbdesc_t **ndesc;
12030 size_t osize, nsize;
12031
12032 /*
12033 * We can't add to enablings after we've enabled them, or after we've
12034 * retained them.
12035 */
12036 ASSERT(enab->dten_probegen == 0);
12037 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
12038
12039 if (enab->dten_ndesc < enab->dten_maxdesc) {
12040 enab->dten_desc[enab->dten_ndesc++] = ecb;
12041 return;
12042 }
12043
12044 osize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
12045
12046 if (enab->dten_maxdesc == 0) {
12047 enab->dten_maxdesc = 1;
12048 } else {
12049 enab->dten_maxdesc <<= 1;
12050 }
12051
12052 ASSERT(enab->dten_ndesc < enab->dten_maxdesc);
12053
12054 nsize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
12055 ndesc = kmem_zalloc(nsize, KM_SLEEP);
12056 bcopy(enab->dten_desc, ndesc, osize);
12057 kmem_free(enab->dten_desc, osize);
12058
12059 enab->dten_desc = ndesc;
12060 enab->dten_desc[enab->dten_ndesc++] = ecb;
12061 }
12062
12063 static void
12064 dtrace_enabling_addlike(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb,
12065 dtrace_probedesc_t *pd)
12066 {
12067 dtrace_ecbdesc_t *new;
12068 dtrace_predicate_t *pred;
12069 dtrace_actdesc_t *act;
12070
12071 /*
12072 * We're going to create a new ECB description that matches the
12073 * specified ECB in every way, but has the specified probe description.
12074 */
12075 new = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
12076
12077 if ((pred = ecb->dted_pred.dtpdd_predicate) != NULL)
12078 dtrace_predicate_hold(pred);
12079
12080 for (act = ecb->dted_action; act != NULL; act = act->dtad_next)
12081 dtrace_actdesc_hold(act);
12082
12083 new->dted_action = ecb->dted_action;
12084 new->dted_pred = ecb->dted_pred;
12085 new->dted_probe = *pd;
12086 new->dted_uarg = ecb->dted_uarg;
12087
12088 dtrace_enabling_add(enab, new);
12089 }
12090
12091 static void
12092 dtrace_enabling_dump(dtrace_enabling_t *enab)
12093 {
12094 int i;
12095
12096 for (i = 0; i < enab->dten_ndesc; i++) {
12097 dtrace_probedesc_t *desc = &enab->dten_desc[i]->dted_probe;
12098
12099 cmn_err(CE_NOTE, "enabling probe %d (%s:%s:%s:%s)", i,
12100 desc->dtpd_provider, desc->dtpd_mod,
12101 desc->dtpd_func, desc->dtpd_name);
12102 }
12103 }
12104
12105 static void
12106 dtrace_enabling_destroy(dtrace_enabling_t *enab)
12107 {
12108 int i;
12109 dtrace_ecbdesc_t *ep;
12110 dtrace_vstate_t *vstate = enab->dten_vstate;
12111
12112 ASSERT(MUTEX_HELD(&dtrace_lock));
12113
12114 for (i = 0; i < enab->dten_ndesc; i++) {
12115 dtrace_actdesc_t *act, *next;
12116 dtrace_predicate_t *pred;
12117
12118 ep = enab->dten_desc[i];
12119
12120 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL)
12121 dtrace_predicate_release(pred, vstate);
12122
12123 for (act = ep->dted_action; act != NULL; act = next) {
12124 next = act->dtad_next;
12125 dtrace_actdesc_release(act, vstate);
12126 }
12127
12128 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
12129 }
12130
12131 kmem_free(enab->dten_desc,
12132 enab->dten_maxdesc * sizeof (dtrace_enabling_t *));
12133
12134 /*
12135 * If this was a retained enabling, decrement the dts_nretained count
12136 * and take it off of the dtrace_retained list.
12137 */
12138 if (enab->dten_prev != NULL || enab->dten_next != NULL ||
12139 dtrace_retained == enab) {
12140 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12141 ASSERT(enab->dten_vstate->dtvs_state->dts_nretained > 0);
12142 enab->dten_vstate->dtvs_state->dts_nretained--;
12143 dtrace_retained_gen++;
12144 }
12145
12146 if (enab->dten_prev == NULL) {
12147 if (dtrace_retained == enab) {
12148 dtrace_retained = enab->dten_next;
12149
12150 if (dtrace_retained != NULL)
12151 dtrace_retained->dten_prev = NULL;
12152 }
12153 } else {
12154 ASSERT(enab != dtrace_retained);
12155 ASSERT(dtrace_retained != NULL);
12156 enab->dten_prev->dten_next = enab->dten_next;
12157 }
12158
12159 if (enab->dten_next != NULL) {
12160 ASSERT(dtrace_retained != NULL);
12161 enab->dten_next->dten_prev = enab->dten_prev;
12162 }
12163
12164 kmem_free(enab, sizeof (dtrace_enabling_t));
12165 }
12166
12167 static int
12168 dtrace_enabling_retain(dtrace_enabling_t *enab)
12169 {
12170 dtrace_state_t *state;
12171
12172 ASSERT(MUTEX_HELD(&dtrace_lock));
12173 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
12174 ASSERT(enab->dten_vstate != NULL);
12175
12176 state = enab->dten_vstate->dtvs_state;
12177 ASSERT(state != NULL);
12178
12179 /*
12180 * We only allow each state to retain dtrace_retain_max enablings.
12181 */
12182 if (state->dts_nretained >= dtrace_retain_max)
12183 return (ENOSPC);
12184
12185 state->dts_nretained++;
12186 dtrace_retained_gen++;
12187
12188 if (dtrace_retained == NULL) {
12189 dtrace_retained = enab;
12190 return (0);
12191 }
12192
12193 enab->dten_next = dtrace_retained;
12194 dtrace_retained->dten_prev = enab;
12195 dtrace_retained = enab;
12196
12197 return (0);
12198 }
12199
12200 static int
12201 dtrace_enabling_replicate(dtrace_state_t *state, dtrace_probedesc_t *match,
12202 dtrace_probedesc_t *create)
12203 {
12204 dtrace_enabling_t *new, *enab;
12205 int found = 0, err = ENOENT;
12206
12207 ASSERT(MUTEX_HELD(&dtrace_lock));
12208 ASSERT(strlen(match->dtpd_provider) < DTRACE_PROVNAMELEN);
12209 ASSERT(strlen(match->dtpd_mod) < DTRACE_MODNAMELEN);
12210 ASSERT(strlen(match->dtpd_func) < DTRACE_FUNCNAMELEN);
12211 ASSERT(strlen(match->dtpd_name) < DTRACE_NAMELEN);
12212
12213 new = dtrace_enabling_create(&state->dts_vstate);
12214
12215 /*
12216 * Iterate over all retained enablings, looking for enablings that
12217 * match the specified state.
12218 */
12219 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
12220 int i;
12221
12222 /*
12223 * dtvs_state can only be NULL for helper enablings -- and
12224 * helper enablings can't be retained.
12225 */
12226 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12227
12228 if (enab->dten_vstate->dtvs_state != state)
12229 continue;
12230
12231 /*
12232 * Now iterate over each probe description; we're looking for
12233 * an exact match to the specified probe description.
12234 */
12235 for (i = 0; i < enab->dten_ndesc; i++) {
12236 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
12237 dtrace_probedesc_t *pd = &ep->dted_probe;
12238
12239 if (strcmp(pd->dtpd_provider, match->dtpd_provider))
12240 continue;
12241
12242 if (strcmp(pd->dtpd_mod, match->dtpd_mod))
12243 continue;
12244
12245 if (strcmp(pd->dtpd_func, match->dtpd_func))
12246 continue;
12247
12248 if (strcmp(pd->dtpd_name, match->dtpd_name))
12249 continue;
12250
12251 /*
12252 * We have a winning probe! Add it to our growing
12253 * enabling.
12254 */
12255 found = 1;
12256 dtrace_enabling_addlike(new, ep, create);
12257 }
12258 }
12259
12260 if (!found || (err = dtrace_enabling_retain(new)) != 0) {
12261 dtrace_enabling_destroy(new);
12262 return (err);
12263 }
12264
12265 return (0);
12266 }
12267
12268 static void
12269 dtrace_enabling_retract(dtrace_state_t *state)
12270 {
12271 dtrace_enabling_t *enab, *next;
12272
12273 ASSERT(MUTEX_HELD(&dtrace_lock));
12274
12275 /*
12276 * Iterate over all retained enablings, destroy the enablings retained
12277 * for the specified state.
12278 */
12279 for (enab = dtrace_retained; enab != NULL; enab = next) {
12280 next = enab->dten_next;
12281
12282 /*
12283 * dtvs_state can only be NULL for helper enablings -- and
12284 * helper enablings can't be retained.
12285 */
12286 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12287
12288 if (enab->dten_vstate->dtvs_state == state) {
12289 ASSERT(state->dts_nretained > 0);
12290 dtrace_enabling_destroy(enab);
12291 }
12292 }
12293
12294 ASSERT(state->dts_nretained == 0);
12295 }
12296
12297 static int
12298 dtrace_enabling_match(dtrace_enabling_t *enab, int *nmatched)
12299 {
12300 int i = 0;
12301 int total_matched = 0, matched = 0;
12302
12303 ASSERT(MUTEX_HELD(&cpu_lock));
12304 ASSERT(MUTEX_HELD(&dtrace_lock));
12305
12306 for (i = 0; i < enab->dten_ndesc; i++) {
12307 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
12308
12309 enab->dten_current = ep;
12310 enab->dten_error = 0;
12311
12312 /*
12313 * If a provider failed to enable a probe then get out and
12314 * let the consumer know we failed.
12315 */
12316 if ((matched = dtrace_probe_enable(&ep->dted_probe, enab)) < 0)
12317 return (EBUSY);
12318
12319 total_matched += matched;
12320
12321 if (enab->dten_error != 0) {
12322 /*
12323 * If we get an error half-way through enabling the
12324 * probes, we kick out -- perhaps with some number of
12325 * them enabled. Leaving enabled probes enabled may
12326 * be slightly confusing for user-level, but we expect
12327 * that no one will attempt to actually drive on in
12328 * the face of such errors. If this is an anonymous
12329 * enabling (indicated with a NULL nmatched pointer),
12330 * we cmn_err() a message. We aren't expecting to
12331 * get such an error -- such as it can exist at all,
12332 * it would be a result of corrupted DOF in the driver
12333 * properties.
12334 */
12335 if (nmatched == NULL) {
12336 cmn_err(CE_WARN, "dtrace_enabling_match() "
12337 "error on %p: %d", (void *)ep,
12338 enab->dten_error);
12339 }
12340
12341 return (enab->dten_error);
12342 }
12343 }
12344
12345 enab->dten_probegen = dtrace_probegen;
12346 if (nmatched != NULL)
12347 *nmatched = total_matched;
12348
12349 return (0);
12350 }
12351
12352 static void
12353 dtrace_enabling_matchall(void)
12354 {
12355 dtrace_enabling_t *enab;
12356
12357 mutex_enter(&cpu_lock);
12358 mutex_enter(&dtrace_lock);
12359
12360 /*
12361 * Iterate over all retained enablings to see if any probes match
12362 * against them. We only perform this operation on enablings for which
12363 * we have sufficient permissions by virtue of being in the global zone
12364 * or in the same zone as the DTrace client. Because we can be called
12365 * after dtrace_detach() has been called, we cannot assert that there
12366 * are retained enablings. We can safely load from dtrace_retained,
12367 * however: the taskq_destroy() at the end of dtrace_detach() will
12368 * block pending our completion.
12369 */
12370 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
12371 dtrace_cred_t *dcr = &enab->dten_vstate->dtvs_state->dts_cred;
12372 cred_t *cr = dcr->dcr_cred;
12373 zoneid_t zone = cr != NULL ? crgetzoneid(cr) : 0;
12374
12375 if ((dcr->dcr_visible & DTRACE_CRV_ALLZONE) || (cr != NULL &&
12376 (zone == GLOBAL_ZONEID || getzoneid() == zone)))
12377 (void) dtrace_enabling_match(enab, NULL);
12378 }
12379
12380 mutex_exit(&dtrace_lock);
12381 mutex_exit(&cpu_lock);
12382 }
12383
12384 /*
12385 * If an enabling is to be enabled without having matched probes (that is, if
12386 * dtrace_state_go() is to be called on the underlying dtrace_state_t), the
12387 * enabling must be _primed_ by creating an ECB for every ECB description.
12388 * This must be done to assure that we know the number of speculations, the
12389 * number of aggregations, the minimum buffer size needed, etc. before we
12390 * transition out of DTRACE_ACTIVITY_INACTIVE. To do this without actually
12391 * enabling any probes, we create ECBs for every ECB decription, but with a
12392 * NULL probe -- which is exactly what this function does.
12393 */
12394 static void
12395 dtrace_enabling_prime(dtrace_state_t *state)
12396 {
12397 dtrace_enabling_t *enab;
12398 int i;
12399
12400 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
12401 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12402
12403 if (enab->dten_vstate->dtvs_state != state)
12404 continue;
12405
12406 /*
12407 * We don't want to prime an enabling more than once, lest
12408 * we allow a malicious user to induce resource exhaustion.
12409 * (The ECBs that result from priming an enabling aren't
12410 * leaked -- but they also aren't deallocated until the
12411 * consumer state is destroyed.)
12412 */
12413 if (enab->dten_primed)
12414 continue;
12415
12416 for (i = 0; i < enab->dten_ndesc; i++) {
12417 enab->dten_current = enab->dten_desc[i];
12418 (void) dtrace_probe_enable(NULL, enab);
12419 }
12420
12421 enab->dten_primed = 1;
12422 }
12423 }
12424
12425 /*
12426 * Called to indicate that probes should be provided due to retained
12427 * enablings. This is implemented in terms of dtrace_probe_provide(), but it
12428 * must take an initial lap through the enabling calling the dtps_provide()
12429 * entry point explicitly to allow for autocreated probes.
12430 */
12431 static void
12432 dtrace_enabling_provide(dtrace_provider_t *prv)
12433 {
12434 int i, all = 0;
12435 dtrace_probedesc_t desc;
12436 dtrace_genid_t gen;
12437
12438 ASSERT(MUTEX_HELD(&dtrace_lock));
12439 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
12440
12441 if (prv == NULL) {
12442 all = 1;
12443 prv = dtrace_provider;
12444 }
12445
12446 do {
12447 dtrace_enabling_t *enab;
12448 void *parg = prv->dtpv_arg;
12449
12450 retry:
12451 gen = dtrace_retained_gen;
12452 for (enab = dtrace_retained; enab != NULL;
12453 enab = enab->dten_next) {
12454 for (i = 0; i < enab->dten_ndesc; i++) {
12455 desc = enab->dten_desc[i]->dted_probe;
12456 mutex_exit(&dtrace_lock);
12457 prv->dtpv_pops.dtps_provide(parg, &desc);
12458 mutex_enter(&dtrace_lock);
12459 /*
12460 * Process the retained enablings again if
12461 * they have changed while we weren't holding
12462 * dtrace_lock.
12463 */
12464 if (gen != dtrace_retained_gen)
12465 goto retry;
12466 }
12467 }
12468 } while (all && (prv = prv->dtpv_next) != NULL);
12469
12470 mutex_exit(&dtrace_lock);
12471 dtrace_probe_provide(NULL, all ? NULL : prv);
12472 mutex_enter(&dtrace_lock);
12473 }
12474
12475 /*
12476 * Called to reap ECBs that are attached to probes from defunct providers.
12477 */
12478 static void
12479 dtrace_enabling_reap(void)
12480 {
12481 dtrace_provider_t *prov;
12482 dtrace_probe_t *probe;
12483 dtrace_ecb_t *ecb;
12484 hrtime_t when;
12485 int i;
12486
12487 mutex_enter(&cpu_lock);
12488 mutex_enter(&dtrace_lock);
12489
12490 for (i = 0; i < dtrace_nprobes; i++) {
12491 if ((probe = dtrace_probes[i]) == NULL)
12492 continue;
12493
12494 if (probe->dtpr_ecb == NULL)
12495 continue;
12496
12497 prov = probe->dtpr_provider;
12498
12499 if ((when = prov->dtpv_defunct) == 0)
12500 continue;
12501
12502 /*
12503 * We have ECBs on a defunct provider: we want to reap these
12504 * ECBs to allow the provider to unregister. The destruction
12505 * of these ECBs must be done carefully: if we destroy the ECB
12506 * and the consumer later wishes to consume an EPID that
12507 * corresponds to the destroyed ECB (and if the EPID metadata
12508 * has not been previously consumed), the consumer will abort
12509 * processing on the unknown EPID. To reduce (but not, sadly,
12510 * eliminate) the possibility of this, we will only destroy an
12511 * ECB for a defunct provider if, for the state that
12512 * corresponds to the ECB:
12513 *
12514 * (a) There is no speculative tracing (which can effectively
12515 * cache an EPID for an arbitrary amount of time).
12516 *
12517 * (b) The principal buffers have been switched twice since the
12518 * provider became defunct.
12519 *
12520 * (c) The aggregation buffers are of zero size or have been
12521 * switched twice since the provider became defunct.
12522 *
12523 * We use dts_speculates to determine (a) and call a function
12524 * (dtrace_buffer_consumed()) to determine (b) and (c). Note
12525 * that as soon as we've been unable to destroy one of the ECBs
12526 * associated with the probe, we quit trying -- reaping is only
12527 * fruitful in as much as we can destroy all ECBs associated
12528 * with the defunct provider's probes.
12529 */
12530 while ((ecb = probe->dtpr_ecb) != NULL) {
12531 dtrace_state_t *state = ecb->dte_state;
12532 dtrace_buffer_t *buf = state->dts_buffer;
12533 dtrace_buffer_t *aggbuf = state->dts_aggbuffer;
12534
12535 if (state->dts_speculates)
12536 break;
12537
12538 if (!dtrace_buffer_consumed(buf, when))
12539 break;
12540
12541 if (!dtrace_buffer_consumed(aggbuf, when))
12542 break;
12543
12544 dtrace_ecb_disable(ecb);
12545 ASSERT(probe->dtpr_ecb != ecb);
12546 dtrace_ecb_destroy(ecb);
12547 }
12548 }
12549
12550 mutex_exit(&dtrace_lock);
12551 mutex_exit(&cpu_lock);
12552 }
12553
12554 /*
12555 * DTrace DOF Functions
12556 */
12557 /*ARGSUSED*/
12558 static void
12559 dtrace_dof_error(dof_hdr_t *dof, const char *str)
12560 {
12561 if (dtrace_err_verbose)
12562 cmn_err(CE_WARN, "failed to process DOF: %s", str);
12563
12564 #ifdef DTRACE_ERRDEBUG
12565 dtrace_errdebug(str);
12566 #endif
12567 }
12568
12569 /*
12570 * Create DOF out of a currently enabled state. Right now, we only create
12571 * DOF containing the run-time options -- but this could be expanded to create
12572 * complete DOF representing the enabled state.
12573 */
12574 static dof_hdr_t *
12575 dtrace_dof_create(dtrace_state_t *state)
12576 {
12577 dof_hdr_t *dof;
12578 dof_sec_t *sec;
12579 dof_optdesc_t *opt;
12580 int i, len = sizeof (dof_hdr_t) +
12581 roundup(sizeof (dof_sec_t), sizeof (uint64_t)) +
12582 sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
12583
12584 ASSERT(MUTEX_HELD(&dtrace_lock));
12585
12586 dof = kmem_zalloc(len, KM_SLEEP);
12587 dof->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
12588 dof->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
12589 dof->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
12590 dof->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;
12591
12592 dof->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_NATIVE;
12593 dof->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
12594 dof->dofh_ident[DOF_ID_VERSION] = DOF_VERSION;
12595 dof->dofh_ident[DOF_ID_DIFVERS] = DIF_VERSION;
12596 dof->dofh_ident[DOF_ID_DIFIREG] = DIF_DIR_NREGS;
12597 dof->dofh_ident[DOF_ID_DIFTREG] = DIF_DTR_NREGS;
12598
12599 dof->dofh_flags = 0;
12600 dof->dofh_hdrsize = sizeof (dof_hdr_t);
12601 dof->dofh_secsize = sizeof (dof_sec_t);
12602 dof->dofh_secnum = 1; /* only DOF_SECT_OPTDESC */
12603 dof->dofh_secoff = sizeof (dof_hdr_t);
12604 dof->dofh_loadsz = len;
12605 dof->dofh_filesz = len;
12606 dof->dofh_pad = 0;
12607
12608 /*
12609 * Fill in the option section header...
12610 */
12611 sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
12612 sec->dofs_type = DOF_SECT_OPTDESC;
12613 sec->dofs_align = sizeof (uint64_t);
12614 sec->dofs_flags = DOF_SECF_LOAD;
12615 sec->dofs_entsize = sizeof (dof_optdesc_t);
12616
12617 opt = (dof_optdesc_t *)((uintptr_t)sec +
12618 roundup(sizeof (dof_sec_t), sizeof (uint64_t)));
12619
12620 sec->dofs_offset = (uintptr_t)opt - (uintptr_t)dof;
12621 sec->dofs_size = sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
12622
12623 for (i = 0; i < DTRACEOPT_MAX; i++) {
12624 opt[i].dofo_option = i;
12625 opt[i].dofo_strtab = DOF_SECIDX_NONE;
12626 opt[i].dofo_value = state->dts_options[i];
12627 }
12628
12629 return (dof);
12630 }
12631
12632 static dof_hdr_t *
12633 dtrace_dof_copyin(uintptr_t uarg, int *errp)
12634 {
12635 dof_hdr_t hdr, *dof;
12636
12637 ASSERT(!MUTEX_HELD(&dtrace_lock));
12638
12639 /*
12640 * First, we're going to copyin() the sizeof (dof_hdr_t).
12641 */
12642 if (copyin((void *)uarg, &hdr, sizeof (hdr)) != 0) {
12643 dtrace_dof_error(NULL, "failed to copyin DOF header");
12644 *errp = EFAULT;
12645 return (NULL);
12646 }
12647
12648 /*
12649 * Now we'll allocate the entire DOF and copy it in -- provided
12650 * that the length isn't outrageous.
12651 */
12652 if (hdr.dofh_loadsz >= dtrace_dof_maxsize) {
12653 dtrace_dof_error(&hdr, "load size exceeds maximum");
12654 *errp = E2BIG;
12655 return (NULL);
12656 }
12657
12658 if (hdr.dofh_loadsz < sizeof (hdr)) {
12659 dtrace_dof_error(&hdr, "invalid load size");
12660 *errp = EINVAL;
12661 return (NULL);
12662 }
12663
12664 dof = kmem_alloc(hdr.dofh_loadsz, KM_SLEEP);
12665
12666 if (copyin((void *)uarg, dof, hdr.dofh_loadsz) != 0 ||
12667 dof->dofh_loadsz != hdr.dofh_loadsz) {
12668 kmem_free(dof, hdr.dofh_loadsz);
12669 *errp = EFAULT;
12670 return (NULL);
12671 }
12672
12673 return (dof);
12674 }
12675
12676 static dof_hdr_t *
12677 dtrace_dof_property(const char *name)
12678 {
12679 uchar_t *buf;
12680 uint64_t loadsz;
12681 unsigned int len, i;
12682 dof_hdr_t *dof;
12683
12684 /*
12685 * Unfortunately, array of values in .conf files are always (and
12686 * only) interpreted to be integer arrays. We must read our DOF
12687 * as an integer array, and then squeeze it into a byte array.
12688 */
12689 if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, dtrace_devi, 0,
12690 (char *)name, (int **)&buf, &len) != DDI_PROP_SUCCESS)
12691 return (NULL);
12692
12693 for (i = 0; i < len; i++)
12694 buf[i] = (uchar_t)(((int *)buf)[i]);
12695
12696 if (len < sizeof (dof_hdr_t)) {
12697 ddi_prop_free(buf);
12698 dtrace_dof_error(NULL, "truncated header");
12699 return (NULL);
12700 }
12701
12702 if (len < (loadsz = ((dof_hdr_t *)buf)->dofh_loadsz)) {
12703 ddi_prop_free(buf);
12704 dtrace_dof_error(NULL, "truncated DOF");
12705 return (NULL);
12706 }
12707
12708 if (loadsz >= dtrace_dof_maxsize) {
12709 ddi_prop_free(buf);
12710 dtrace_dof_error(NULL, "oversized DOF");
12711 return (NULL);
12712 }
12713
12714 dof = kmem_alloc(loadsz, KM_SLEEP);
12715 bcopy(buf, dof, loadsz);
12716 ddi_prop_free(buf);
12717
12718 return (dof);
12719 }
12720
12721 static void
12722 dtrace_dof_destroy(dof_hdr_t *dof)
12723 {
12724 kmem_free(dof, dof->dofh_loadsz);
12725 }
12726
12727 /*
12728 * Return the dof_sec_t pointer corresponding to a given section index. If the
12729 * index is not valid, dtrace_dof_error() is called and NULL is returned. If
12730 * a type other than DOF_SECT_NONE is specified, the header is checked against
12731 * this type and NULL is returned if the types do not match.
12732 */
12733 static dof_sec_t *
12734 dtrace_dof_sect(dof_hdr_t *dof, uint32_t type, dof_secidx_t i)
12735 {
12736 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)
12737 ((uintptr_t)dof + dof->dofh_secoff + i * dof->dofh_secsize);
12738
12739 if (i >= dof->dofh_secnum) {
12740 dtrace_dof_error(dof, "referenced section index is invalid");
12741 return (NULL);
12742 }
12743
12744 if (!(sec->dofs_flags & DOF_SECF_LOAD)) {
12745 dtrace_dof_error(dof, "referenced section is not loadable");
12746 return (NULL);
12747 }
12748
12749 if (type != DOF_SECT_NONE && type != sec->dofs_type) {
12750 dtrace_dof_error(dof, "referenced section is the wrong type");
12751 return (NULL);
12752 }
12753
12754 return (sec);
12755 }
12756
12757 static dtrace_probedesc_t *
12758 dtrace_dof_probedesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_probedesc_t *desc)
12759 {
12760 dof_probedesc_t *probe;
12761 dof_sec_t *strtab;
12762 uintptr_t daddr = (uintptr_t)dof;
12763 uintptr_t str;
12764 size_t size;
12765
12766 if (sec->dofs_type != DOF_SECT_PROBEDESC) {
12767 dtrace_dof_error(dof, "invalid probe section");
12768 return (NULL);
12769 }
12770
12771 if (sec->dofs_align != sizeof (dof_secidx_t)) {
12772 dtrace_dof_error(dof, "bad alignment in probe description");
12773 return (NULL);
12774 }
12775
12776 if (sec->dofs_offset + sizeof (dof_probedesc_t) > dof->dofh_loadsz) {
12777 dtrace_dof_error(dof, "truncated probe description");
12778 return (NULL);
12779 }
12780
12781 probe = (dof_probedesc_t *)(uintptr_t)(daddr + sec->dofs_offset);
12782 strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, probe->dofp_strtab);
12783
12784 if (strtab == NULL)
12785 return (NULL);
12786
12787 str = daddr + strtab->dofs_offset;
12788 size = strtab->dofs_size;
12789
12790 if (probe->dofp_provider >= strtab->dofs_size) {
12791 dtrace_dof_error(dof, "corrupt probe provider");
12792 return (NULL);
12793 }
12794
12795 (void) strncpy(desc->dtpd_provider,
12796 (char *)(str + probe->dofp_provider),
12797 MIN(DTRACE_PROVNAMELEN - 1, size - probe->dofp_provider));
12798
12799 if (probe->dofp_mod >= strtab->dofs_size) {
12800 dtrace_dof_error(dof, "corrupt probe module");
12801 return (NULL);
12802 }
12803
12804 (void) strncpy(desc->dtpd_mod, (char *)(str + probe->dofp_mod),
12805 MIN(DTRACE_MODNAMELEN - 1, size - probe->dofp_mod));
12806
12807 if (probe->dofp_func >= strtab->dofs_size) {
12808 dtrace_dof_error(dof, "corrupt probe function");
12809 return (NULL);
12810 }
12811
12812 (void) strncpy(desc->dtpd_func, (char *)(str + probe->dofp_func),
12813 MIN(DTRACE_FUNCNAMELEN - 1, size - probe->dofp_func));
12814
12815 if (probe->dofp_name >= strtab->dofs_size) {
12816 dtrace_dof_error(dof, "corrupt probe name");
12817 return (NULL);
12818 }
12819
12820 (void) strncpy(desc->dtpd_name, (char *)(str + probe->dofp_name),
12821 MIN(DTRACE_NAMELEN - 1, size - probe->dofp_name));
12822
12823 return (desc);
12824 }
12825
12826 static dtrace_difo_t *
12827 dtrace_dof_difo(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
12828 cred_t *cr)
12829 {
12830 dtrace_difo_t *dp;
12831 size_t ttl = 0;
12832 dof_difohdr_t *dofd;
12833 uintptr_t daddr = (uintptr_t)dof;
12834 size_t max = dtrace_difo_maxsize;
12835 int i, l, n;
12836
12837 static const struct {
12838 int section;
12839 int bufoffs;
12840 int lenoffs;
12841 int entsize;
12842 int align;
12843 const char *msg;
12844 } difo[] = {
12845 { DOF_SECT_DIF, offsetof(dtrace_difo_t, dtdo_buf),
12846 offsetof(dtrace_difo_t, dtdo_len), sizeof (dif_instr_t),
12847 sizeof (dif_instr_t), "multiple DIF sections" },
12848
12849 { DOF_SECT_INTTAB, offsetof(dtrace_difo_t, dtdo_inttab),
12850 offsetof(dtrace_difo_t, dtdo_intlen), sizeof (uint64_t),
12851 sizeof (uint64_t), "multiple integer tables" },
12852
12853 { DOF_SECT_STRTAB, offsetof(dtrace_difo_t, dtdo_strtab),
12854 offsetof(dtrace_difo_t, dtdo_strlen), 0,
12855 sizeof (char), "multiple string tables" },
12856
12857 { DOF_SECT_VARTAB, offsetof(dtrace_difo_t, dtdo_vartab),
12858 offsetof(dtrace_difo_t, dtdo_varlen), sizeof (dtrace_difv_t),
12859 sizeof (uint_t), "multiple variable tables" },
12860
12861 { DOF_SECT_NONE, 0, 0, 0, 0, NULL }
12862 };
12863
12864 if (sec->dofs_type != DOF_SECT_DIFOHDR) {
12865 dtrace_dof_error(dof, "invalid DIFO header section");
12866 return (NULL);
12867 }
12868
12869 if (sec->dofs_align != sizeof (dof_secidx_t)) {
12870 dtrace_dof_error(dof, "bad alignment in DIFO header");
12871 return (NULL);
12872 }
12873
12874 if (sec->dofs_size < sizeof (dof_difohdr_t) ||
12875 sec->dofs_size % sizeof (dof_secidx_t)) {
12876 dtrace_dof_error(dof, "bad size in DIFO header");
12877 return (NULL);
12878 }
12879
12880 dofd = (dof_difohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
12881 n = (sec->dofs_size - sizeof (*dofd)) / sizeof (dof_secidx_t) + 1;
12882
12883 dp = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
12884 dp->dtdo_rtype = dofd->dofd_rtype;
12885
12886 for (l = 0; l < n; l++) {
12887 dof_sec_t *subsec;
12888 void **bufp;
12889 uint32_t *lenp;
12890
12891 if ((subsec = dtrace_dof_sect(dof, DOF_SECT_NONE,
12892 dofd->dofd_links[l])) == NULL)
12893 goto err; /* invalid section link */
12894
12895 if (ttl + subsec->dofs_size > max) {
12896 dtrace_dof_error(dof, "exceeds maximum size");
12897 goto err;
12898 }
12899
12900 ttl += subsec->dofs_size;
12901
12902 for (i = 0; difo[i].section != DOF_SECT_NONE; i++) {
12903 if (subsec->dofs_type != difo[i].section)
12904 continue;
12905
12906 if (!(subsec->dofs_flags & DOF_SECF_LOAD)) {
12907 dtrace_dof_error(dof, "section not loaded");
12908 goto err;
12909 }
12910
12911 if (subsec->dofs_align != difo[i].align) {
12912 dtrace_dof_error(dof, "bad alignment");
12913 goto err;
12914 }
12915
12916 bufp = (void **)((uintptr_t)dp + difo[i].bufoffs);
12917 lenp = (uint32_t *)((uintptr_t)dp + difo[i].lenoffs);
12918
12919 if (*bufp != NULL) {
12920 dtrace_dof_error(dof, difo[i].msg);
12921 goto err;
12922 }
12923
12924 if (difo[i].entsize != subsec->dofs_entsize) {
12925 dtrace_dof_error(dof, "entry size mismatch");
12926 goto err;
12927 }
12928
12929 if (subsec->dofs_entsize != 0 &&
12930 (subsec->dofs_size % subsec->dofs_entsize) != 0) {
12931 dtrace_dof_error(dof, "corrupt entry size");
12932 goto err;
12933 }
12934
12935 *lenp = subsec->dofs_size;
12936 *bufp = kmem_alloc(subsec->dofs_size, KM_SLEEP);
12937 bcopy((char *)(uintptr_t)(daddr + subsec->dofs_offset),
12938 *bufp, subsec->dofs_size);
12939
12940 if (subsec->dofs_entsize != 0)
12941 *lenp /= subsec->dofs_entsize;
12942
12943 break;
12944 }
12945
12946 /*
12947 * If we encounter a loadable DIFO sub-section that is not
12948 * known to us, assume this is a broken program and fail.
12949 */
12950 if (difo[i].section == DOF_SECT_NONE &&
12951 (subsec->dofs_flags & DOF_SECF_LOAD)) {
12952 dtrace_dof_error(dof, "unrecognized DIFO subsection");
12953 goto err;
12954 }
12955 }
12956
12957 if (dp->dtdo_buf == NULL) {
12958 /*
12959 * We can't have a DIF object without DIF text.
12960 */
12961 dtrace_dof_error(dof, "missing DIF text");
12962 goto err;
12963 }
12964
12965 /*
12966 * Before we validate the DIF object, run through the variable table
12967 * looking for the strings -- if any of their size are under, we'll set
12968 * their size to be the system-wide default string size. Note that
12969 * this should _not_ happen if the "strsize" option has been set --
12970 * in this case, the compiler should have set the size to reflect the
12971 * setting of the option.
12972 */
12973 for (i = 0; i < dp->dtdo_varlen; i++) {
12974 dtrace_difv_t *v = &dp->dtdo_vartab[i];
12975 dtrace_diftype_t *t = &v->dtdv_type;
12976
12977 if (v->dtdv_id < DIF_VAR_OTHER_UBASE)
12978 continue;
12979
12980 if (t->dtdt_kind == DIF_TYPE_STRING && t->dtdt_size == 0)
12981 t->dtdt_size = dtrace_strsize_default;
12982 }
12983
12984 if (dtrace_difo_validate(dp, vstate, DIF_DIR_NREGS, cr) != 0)
12985 goto err;
12986
12987 dtrace_difo_init(dp, vstate);
12988 return (dp);
12989
12990 err:
12991 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
12992 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
12993 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
12994 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
12995
12996 kmem_free(dp, sizeof (dtrace_difo_t));
12997 return (NULL);
12998 }
12999
13000 static dtrace_predicate_t *
13001 dtrace_dof_predicate(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
13002 cred_t *cr)
13003 {
13004 dtrace_difo_t *dp;
13005
13006 if ((dp = dtrace_dof_difo(dof, sec, vstate, cr)) == NULL)
13007 return (NULL);
13008
13009 return (dtrace_predicate_create(dp));
13010 }
13011
13012 static dtrace_actdesc_t *
13013 dtrace_dof_actdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
13014 cred_t *cr)
13015 {
13016 dtrace_actdesc_t *act, *first = NULL, *last = NULL, *next;
13017 dof_actdesc_t *desc;
13018 dof_sec_t *difosec;
13019 size_t offs;
13020 uintptr_t daddr = (uintptr_t)dof;
13021 uint64_t arg;
13022 dtrace_actkind_t kind;
13023
13024 if (sec->dofs_type != DOF_SECT_ACTDESC) {
13025 dtrace_dof_error(dof, "invalid action section");
13026 return (NULL);
13027 }
13028
13029 if (sec->dofs_offset + sizeof (dof_actdesc_t) > dof->dofh_loadsz) {
13030 dtrace_dof_error(dof, "truncated action description");
13031 return (NULL);
13032 }
13033
13034 if (sec->dofs_align != sizeof (uint64_t)) {
13035 dtrace_dof_error(dof, "bad alignment in action description");
13036 return (NULL);
13037 }
13038
13039 if (sec->dofs_size < sec->dofs_entsize) {
13040 dtrace_dof_error(dof, "section entry size exceeds total size");
13041 return (NULL);
13042 }
13043
13044 if (sec->dofs_entsize != sizeof (dof_actdesc_t)) {
13045 dtrace_dof_error(dof, "bad entry size in action description");
13046 return (NULL);
13047 }
13048
13049 if (sec->dofs_size / sec->dofs_entsize > dtrace_actions_max) {
13050 dtrace_dof_error(dof, "actions exceed dtrace_actions_max");
13051 return (NULL);
13052 }
13053
13054 for (offs = 0; offs < sec->dofs_size; offs += sec->dofs_entsize) {
13055 desc = (dof_actdesc_t *)(daddr +
13056 (uintptr_t)sec->dofs_offset + offs);
13057 kind = (dtrace_actkind_t)desc->dofa_kind;
13058
13059 if ((DTRACEACT_ISPRINTFLIKE(kind) &&
13060 (kind != DTRACEACT_PRINTA ||
13061 desc->dofa_strtab != DOF_SECIDX_NONE)) ||
13062 (kind == DTRACEACT_DIFEXPR &&
13063 desc->dofa_strtab != DOF_SECIDX_NONE)) {
13064 dof_sec_t *strtab;
13065 char *str, *fmt;
13066 uint64_t i;
13067
13068 /*
13069 * The argument to these actions is an index into the
13070 * DOF string table. For printf()-like actions, this
13071 * is the format string. For print(), this is the
13072 * CTF type of the expression result.
13073 */
13074 if ((strtab = dtrace_dof_sect(dof,
13075 DOF_SECT_STRTAB, desc->dofa_strtab)) == NULL)
13076 goto err;
13077
13078 str = (char *)((uintptr_t)dof +
13079 (uintptr_t)strtab->dofs_offset);
13080
13081 for (i = desc->dofa_arg; i < strtab->dofs_size; i++) {
13082 if (str[i] == '\0')
13083 break;
13084 }
13085
13086 if (i >= strtab->dofs_size) {
13087 dtrace_dof_error(dof, "bogus format string");
13088 goto err;
13089 }
13090
13091 if (i == desc->dofa_arg) {
13092 dtrace_dof_error(dof, "empty format string");
13093 goto err;
13094 }
13095
13096 i -= desc->dofa_arg;
13097 fmt = kmem_alloc(i + 1, KM_SLEEP);
13098 bcopy(&str[desc->dofa_arg], fmt, i + 1);
13099 arg = (uint64_t)(uintptr_t)fmt;
13100 } else {
13101 if (kind == DTRACEACT_PRINTA) {
13102 ASSERT(desc->dofa_strtab == DOF_SECIDX_NONE);
13103 arg = 0;
13104 } else {
13105 arg = desc->dofa_arg;
13106 }
13107 }
13108
13109 act = dtrace_actdesc_create(kind, desc->dofa_ntuple,
13110 desc->dofa_uarg, arg);
13111
13112 if (last != NULL) {
13113 last->dtad_next = act;
13114 } else {
13115 first = act;
13116 }
13117
13118 last = act;
13119
13120 if (desc->dofa_difo == DOF_SECIDX_NONE)
13121 continue;
13122
13123 if ((difosec = dtrace_dof_sect(dof,
13124 DOF_SECT_DIFOHDR, desc->dofa_difo)) == NULL)
13125 goto err;
13126
13127 act->dtad_difo = dtrace_dof_difo(dof, difosec, vstate, cr);
13128
13129 if (act->dtad_difo == NULL)
13130 goto err;
13131 }
13132
13133 ASSERT(first != NULL);
13134 return (first);
13135
13136 err:
13137 for (act = first; act != NULL; act = next) {
13138 next = act->dtad_next;
13139 dtrace_actdesc_release(act, vstate);
13140 }
13141
13142 return (NULL);
13143 }
13144
13145 static dtrace_ecbdesc_t *
13146 dtrace_dof_ecbdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
13147 cred_t *cr)
13148 {
13149 dtrace_ecbdesc_t *ep;
13150 dof_ecbdesc_t *ecb;
13151 dtrace_probedesc_t *desc;
13152 dtrace_predicate_t *pred = NULL;
13153
13154 if (sec->dofs_size < sizeof (dof_ecbdesc_t)) {
13155 dtrace_dof_error(dof, "truncated ECB description");
13156 return (NULL);
13157 }
13158
13159 if (sec->dofs_align != sizeof (uint64_t)) {
13160 dtrace_dof_error(dof, "bad alignment in ECB description");
13161 return (NULL);
13162 }
13163
13164 ecb = (dof_ecbdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset);
13165 sec = dtrace_dof_sect(dof, DOF_SECT_PROBEDESC, ecb->dofe_probes);
13166
13167 if (sec == NULL)
13168 return (NULL);
13169
13170 ep = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
13171 ep->dted_uarg = ecb->dofe_uarg;
13172 desc = &ep->dted_probe;
13173
13174 if (dtrace_dof_probedesc(dof, sec, desc) == NULL)
13175 goto err;
13176
13177 if (ecb->dofe_pred != DOF_SECIDX_NONE) {
13178 if ((sec = dtrace_dof_sect(dof,
13179 DOF_SECT_DIFOHDR, ecb->dofe_pred)) == NULL)
13180 goto err;
13181
13182 if ((pred = dtrace_dof_predicate(dof, sec, vstate, cr)) == NULL)
13183 goto err;
13184
13185 ep->dted_pred.dtpdd_predicate = pred;
13186 }
13187
13188 if (ecb->dofe_actions != DOF_SECIDX_NONE) {
13189 if ((sec = dtrace_dof_sect(dof,
13190 DOF_SECT_ACTDESC, ecb->dofe_actions)) == NULL)
13191 goto err;
13192
13193 ep->dted_action = dtrace_dof_actdesc(dof, sec, vstate, cr);
13194
13195 if (ep->dted_action == NULL)
13196 goto err;
13197 }
13198
13199 return (ep);
13200
13201 err:
13202 if (pred != NULL)
13203 dtrace_predicate_release(pred, vstate);
13204 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
13205 return (NULL);
13206 }
13207
13208 /*
13209 * Apply the relocations from the specified 'sec' (a DOF_SECT_URELHDR) to the
13210 * specified DOF. At present, this amounts to simply adding 'ubase' to the
13211 * site of any user SETX relocations to account for load object base address.
13212 * In the future, if we need other relocations, this function can be extended.
13213 */
13214 static int
13215 dtrace_dof_relocate(dof_hdr_t *dof, dof_sec_t *sec, uint64_t ubase)
13216 {
13217 uintptr_t daddr = (uintptr_t)dof;
13218 uintptr_t ts_end;
13219 dof_relohdr_t *dofr =
13220 (dof_relohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
13221 dof_sec_t *ss, *rs, *ts;
13222 dof_relodesc_t *r;
13223 uint_t i, n;
13224
13225 if (sec->dofs_size < sizeof (dof_relohdr_t) ||
13226 sec->dofs_align != sizeof (dof_secidx_t)) {
13227 dtrace_dof_error(dof, "invalid relocation header");
13228 return (-1);
13229 }
13230
13231 ss = dtrace_dof_sect(dof, DOF_SECT_STRTAB, dofr->dofr_strtab);
13232 rs = dtrace_dof_sect(dof, DOF_SECT_RELTAB, dofr->dofr_relsec);
13233 ts = dtrace_dof_sect(dof, DOF_SECT_NONE, dofr->dofr_tgtsec);
13234 ts_end = (uintptr_t)ts + sizeof (dof_sec_t);
13235
13236 if (ss == NULL || rs == NULL || ts == NULL)
13237 return (-1); /* dtrace_dof_error() has been called already */
13238
13239 if (rs->dofs_entsize < sizeof (dof_relodesc_t) ||
13240 rs->dofs_align != sizeof (uint64_t)) {
13241 dtrace_dof_error(dof, "invalid relocation section");
13242 return (-1);
13243 }
13244
13245 r = (dof_relodesc_t *)(uintptr_t)(daddr + rs->dofs_offset);
13246 n = rs->dofs_size / rs->dofs_entsize;
13247
13248 for (i = 0; i < n; i++) {
13249 uintptr_t taddr = daddr + ts->dofs_offset + r->dofr_offset;
13250
13251 switch (r->dofr_type) {
13252 case DOF_RELO_NONE:
13253 break;
13254 case DOF_RELO_SETX:
13255 if (r->dofr_offset >= ts->dofs_size || r->dofr_offset +
13256 sizeof (uint64_t) > ts->dofs_size) {
13257 dtrace_dof_error(dof, "bad relocation offset");
13258 return (-1);
13259 }
13260
13261 if (taddr >= (uintptr_t)ts && taddr < ts_end) {
13262 dtrace_dof_error(dof, "bad relocation offset");
13263 return (-1);
13264 }
13265
13266 if (!IS_P2ALIGNED(taddr, sizeof (uint64_t))) {
13267 dtrace_dof_error(dof, "misaligned setx relo");
13268 return (-1);
13269 }
13270
13271 *(uint64_t *)taddr += ubase;
13272 break;
13273 default:
13274 dtrace_dof_error(dof, "invalid relocation type");
13275 return (-1);
13276 }
13277
13278 r = (dof_relodesc_t *)((uintptr_t)r + rs->dofs_entsize);
13279 }
13280
13281 return (0);
13282 }
13283
13284 /*
13285 * The dof_hdr_t passed to dtrace_dof_slurp() should be a partially validated
13286 * header: it should be at the front of a memory region that is at least
13287 * sizeof (dof_hdr_t) in size -- and then at least dof_hdr.dofh_loadsz in
13288 * size. It need not be validated in any other way.
13289 */
13290 static int
13291 dtrace_dof_slurp(dof_hdr_t *dof, dtrace_vstate_t *vstate, cred_t *cr,
13292 dtrace_enabling_t **enabp, uint64_t ubase, int noprobes)
13293 {
13294 uint64_t len = dof->dofh_loadsz, seclen;
13295 uintptr_t daddr = (uintptr_t)dof;
13296 dtrace_ecbdesc_t *ep;
13297 dtrace_enabling_t *enab;
13298 uint_t i;
13299
13300 ASSERT(MUTEX_HELD(&dtrace_lock));
13301 ASSERT(dof->dofh_loadsz >= sizeof (dof_hdr_t));
13302
13303 /*
13304 * Check the DOF header identification bytes. In addition to checking
13305 * valid settings, we also verify that unused bits/bytes are zeroed so
13306 * we can use them later without fear of regressing existing binaries.
13307 */
13308 if (bcmp(&dof->dofh_ident[DOF_ID_MAG0],
13309 DOF_MAG_STRING, DOF_MAG_STRLEN) != 0) {
13310 dtrace_dof_error(dof, "DOF magic string mismatch");
13311 return (-1);
13312 }
13313
13314 if (dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_ILP32 &&
13315 dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_LP64) {
13316 dtrace_dof_error(dof, "DOF has invalid data model");
13317 return (-1);
13318 }
13319
13320 if (dof->dofh_ident[DOF_ID_ENCODING] != DOF_ENCODE_NATIVE) {
13321 dtrace_dof_error(dof, "DOF encoding mismatch");
13322 return (-1);
13323 }
13324
13325 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
13326 dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_2) {
13327 dtrace_dof_error(dof, "DOF version mismatch");
13328 return (-1);
13329 }
13330
13331 if (dof->dofh_ident[DOF_ID_DIFVERS] != DIF_VERSION_2) {
13332 dtrace_dof_error(dof, "DOF uses unsupported instruction set");
13333 return (-1);
13334 }
13335
13336 if (dof->dofh_ident[DOF_ID_DIFIREG] > DIF_DIR_NREGS) {
13337 dtrace_dof_error(dof, "DOF uses too many integer registers");
13338 return (-1);
13339 }
13340
13341 if (dof->dofh_ident[DOF_ID_DIFTREG] > DIF_DTR_NREGS) {
13342 dtrace_dof_error(dof, "DOF uses too many tuple registers");
13343 return (-1);
13344 }
13345
13346 for (i = DOF_ID_PAD; i < DOF_ID_SIZE; i++) {
13347 if (dof->dofh_ident[i] != 0) {
13348 dtrace_dof_error(dof, "DOF has invalid ident byte set");
13349 return (-1);
13350 }
13351 }
13352
13353 if (dof->dofh_flags & ~DOF_FL_VALID) {
13354 dtrace_dof_error(dof, "DOF has invalid flag bits set");
13355 return (-1);
13356 }
13357
13358 if (dof->dofh_secsize == 0) {
13359 dtrace_dof_error(dof, "zero section header size");
13360 return (-1);
13361 }
13362
13363 /*
13364 * Check that the section headers don't exceed the amount of DOF
13365 * data. Note that we cast the section size and number of sections
13366 * to uint64_t's to prevent possible overflow in the multiplication.
13367 */
13368 seclen = (uint64_t)dof->dofh_secnum * (uint64_t)dof->dofh_secsize;
13369
13370 if (dof->dofh_secoff > len || seclen > len ||
13371 dof->dofh_secoff + seclen > len) {
13372 dtrace_dof_error(dof, "truncated section headers");
13373 return (-1);
13374 }
13375
13376 if (!IS_P2ALIGNED(dof->dofh_secoff, sizeof (uint64_t))) {
13377 dtrace_dof_error(dof, "misaligned section headers");
13378 return (-1);
13379 }
13380
13381 if (!IS_P2ALIGNED(dof->dofh_secsize, sizeof (uint64_t))) {
13382 dtrace_dof_error(dof, "misaligned section size");
13383 return (-1);
13384 }
13385
13386 /*
13387 * Take an initial pass through the section headers to be sure that
13388 * the headers don't have stray offsets. If the 'noprobes' flag is
13389 * set, do not permit sections relating to providers, probes, or args.
13390 */
13391 for (i = 0; i < dof->dofh_secnum; i++) {
13392 dof_sec_t *sec = (dof_sec_t *)(daddr +
13393 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13394
13395 if (noprobes) {
13396 switch (sec->dofs_type) {
13397 case DOF_SECT_PROVIDER:
13398 case DOF_SECT_PROBES:
13399 case DOF_SECT_PRARGS:
13400 case DOF_SECT_PROFFS:
13401 dtrace_dof_error(dof, "illegal sections "
13402 "for enabling");
13403 return (-1);
13404 }
13405 }
13406
13407 if (DOF_SEC_ISLOADABLE(sec->dofs_type) &&
13408 !(sec->dofs_flags & DOF_SECF_LOAD)) {
13409 dtrace_dof_error(dof, "loadable section with load "
13410 "flag unset");
13411 return (-1);
13412 }
13413
13414 if (!(sec->dofs_flags & DOF_SECF_LOAD))
13415 continue; /* just ignore non-loadable sections */
13416
13417 if (!ISP2(sec->dofs_align)) {
13418 dtrace_dof_error(dof, "bad section alignment");
13419 return (-1);
13420 }
13421
13422 if (sec->dofs_offset & (sec->dofs_align - 1)) {
13423 dtrace_dof_error(dof, "misaligned section");
13424 return (-1);
13425 }
13426
13427 if (sec->dofs_offset > len || sec->dofs_size > len ||
13428 sec->dofs_offset + sec->dofs_size > len) {
13429 dtrace_dof_error(dof, "corrupt section header");
13430 return (-1);
13431 }
13432
13433 if (sec->dofs_type == DOF_SECT_STRTAB && *((char *)daddr +
13434 sec->dofs_offset + sec->dofs_size - 1) != '\0') {
13435 dtrace_dof_error(dof, "non-terminating string table");
13436 return (-1);
13437 }
13438 }
13439
13440 /*
13441 * Take a second pass through the sections and locate and perform any
13442 * relocations that are present. We do this after the first pass to
13443 * be sure that all sections have had their headers validated.
13444 */
13445 for (i = 0; i < dof->dofh_secnum; i++) {
13446 dof_sec_t *sec = (dof_sec_t *)(daddr +
13447 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13448
13449 if (!(sec->dofs_flags & DOF_SECF_LOAD))
13450 continue; /* skip sections that are not loadable */
13451
13452 switch (sec->dofs_type) {
13453 case DOF_SECT_URELHDR:
13454 if (dtrace_dof_relocate(dof, sec, ubase) != 0)
13455 return (-1);
13456 break;
13457 }
13458 }
13459
13460 if ((enab = *enabp) == NULL)
13461 enab = *enabp = dtrace_enabling_create(vstate);
13462
13463 for (i = 0; i < dof->dofh_secnum; i++) {
13464 dof_sec_t *sec = (dof_sec_t *)(daddr +
13465 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13466
13467 if (sec->dofs_type != DOF_SECT_ECBDESC)
13468 continue;
13469
13470 if ((ep = dtrace_dof_ecbdesc(dof, sec, vstate, cr)) == NULL) {
13471 dtrace_enabling_destroy(enab);
13472 *enabp = NULL;
13473 return (-1);
13474 }
13475
13476 dtrace_enabling_add(enab, ep);
13477 }
13478
13479 return (0);
13480 }
13481
13482 /*
13483 * Process DOF for any options. This routine assumes that the DOF has been
13484 * at least processed by dtrace_dof_slurp().
13485 */
13486 static int
13487 dtrace_dof_options(dof_hdr_t *dof, dtrace_state_t *state)
13488 {
13489 int i, rval;
13490 uint32_t entsize;
13491 size_t offs;
13492 dof_optdesc_t *desc;
13493
13494 for (i = 0; i < dof->dofh_secnum; i++) {
13495 dof_sec_t *sec = (dof_sec_t *)((uintptr_t)dof +
13496 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13497
13498 if (sec->dofs_type != DOF_SECT_OPTDESC)
13499 continue;
13500
13501 if (sec->dofs_align != sizeof (uint64_t)) {
13502 dtrace_dof_error(dof, "bad alignment in "
13503 "option description");
13504 return (EINVAL);
13505 }
13506
13507 if ((entsize = sec->dofs_entsize) == 0) {
13508 dtrace_dof_error(dof, "zeroed option entry size");
13509 return (EINVAL);
13510 }
13511
13512 if (entsize < sizeof (dof_optdesc_t)) {
13513 dtrace_dof_error(dof, "bad option entry size");
13514 return (EINVAL);
13515 }
13516
13517 for (offs = 0; offs < sec->dofs_size; offs += entsize) {
13518 desc = (dof_optdesc_t *)((uintptr_t)dof +
13519 (uintptr_t)sec->dofs_offset + offs);
13520
13521 if (desc->dofo_strtab != DOF_SECIDX_NONE) {
13522 dtrace_dof_error(dof, "non-zero option string");
13523 return (EINVAL);
13524 }
13525
13526 if (desc->dofo_value == DTRACEOPT_UNSET) {
13527 dtrace_dof_error(dof, "unset option");
13528 return (EINVAL);
13529 }
13530
13531 if ((rval = dtrace_state_option(state,
13532 desc->dofo_option, desc->dofo_value)) != 0) {
13533 dtrace_dof_error(dof, "rejected option");
13534 return (rval);
13535 }
13536 }
13537 }
13538
13539 return (0);
13540 }
13541
13542 /*
13543 * DTrace Consumer State Functions
13544 */
13545 int
13546 dtrace_dstate_init(dtrace_dstate_t *dstate, size_t size)
13547 {
13548 size_t hashsize, maxper, min, chunksize = dstate->dtds_chunksize;
13549 void *base;
13550 uintptr_t limit;
13551 dtrace_dynvar_t *dvar, *next, *start;
13552 int i;
13553
13554 ASSERT(MUTEX_HELD(&dtrace_lock));
13555 ASSERT(dstate->dtds_base == NULL && dstate->dtds_percpu == NULL);
13556
13557 bzero(dstate, sizeof (dtrace_dstate_t));
13558
13559 if ((dstate->dtds_chunksize = chunksize) == 0)
13560 dstate->dtds_chunksize = DTRACE_DYNVAR_CHUNKSIZE;
13561
13562 VERIFY(dstate->dtds_chunksize < LONG_MAX);
13563
13564 if (size < (min = dstate->dtds_chunksize + sizeof (dtrace_dynhash_t)))
13565 size = min;
13566
13567 if ((base = kmem_zalloc(size, KM_NOSLEEP | KM_NORMALPRI)) == NULL)
13568 return (ENOMEM);
13569
13570 dstate->dtds_size = size;
13571 dstate->dtds_base = base;
13572 dstate->dtds_percpu = kmem_cache_alloc(dtrace_state_cache, KM_SLEEP);
13573 bzero(dstate->dtds_percpu, NCPU * sizeof (dtrace_dstate_percpu_t));
13574
13575 hashsize = size / (dstate->dtds_chunksize + sizeof (dtrace_dynhash_t));
13576
13577 if (hashsize != 1 && (hashsize & 1))
13578 hashsize--;
13579
13580 dstate->dtds_hashsize = hashsize;
13581 dstate->dtds_hash = dstate->dtds_base;
13582
13583 /*
13584 * Set all of our hash buckets to point to the single sink, and (if
13585 * it hasn't already been set), set the sink's hash value to be the
13586 * sink sentinel value. The sink is needed for dynamic variable
13587 * lookups to know that they have iterated over an entire, valid hash
13588 * chain.
13589 */
13590 for (i = 0; i < hashsize; i++)
13591 dstate->dtds_hash[i].dtdh_chain = &dtrace_dynhash_sink;
13592
13593 if (dtrace_dynhash_sink.dtdv_hashval != DTRACE_DYNHASH_SINK)
13594 dtrace_dynhash_sink.dtdv_hashval = DTRACE_DYNHASH_SINK;
13595
13596 /*
13597 * Determine number of active CPUs. Divide free list evenly among
13598 * active CPUs.
13599 */
13600 start = (dtrace_dynvar_t *)
13601 ((uintptr_t)base + hashsize * sizeof (dtrace_dynhash_t));
13602 limit = (uintptr_t)base + size;
13603
13604 VERIFY((uintptr_t)start < limit);
13605 VERIFY((uintptr_t)start >= (uintptr_t)base);
13606
13607 maxper = (limit - (uintptr_t)start) / NCPU;
13608 maxper = (maxper / dstate->dtds_chunksize) * dstate->dtds_chunksize;
13609
13610 for (i = 0; i < NCPU; i++) {
13611 dstate->dtds_percpu[i].dtdsc_free = dvar = start;
13612
13613 /*
13614 * If we don't even have enough chunks to make it once through
13615 * NCPUs, we're just going to allocate everything to the first
13616 * CPU. And if we're on the last CPU, we're going to allocate
13617 * whatever is left over. In either case, we set the limit to
13618 * be the limit of the dynamic variable space.
13619 */
13620 if (maxper == 0 || i == NCPU - 1) {
13621 limit = (uintptr_t)base + size;
13622 start = NULL;
13623 } else {
13624 limit = (uintptr_t)start + maxper;
13625 start = (dtrace_dynvar_t *)limit;
13626 }
13627
13628 VERIFY(limit <= (uintptr_t)base + size);
13629
13630 for (;;) {
13631 next = (dtrace_dynvar_t *)((uintptr_t)dvar +
13632 dstate->dtds_chunksize);
13633
13634 if ((uintptr_t)next + dstate->dtds_chunksize >= limit)
13635 break;
13636
13637 VERIFY((uintptr_t)dvar >= (uintptr_t)base &&
13638 (uintptr_t)dvar <= (uintptr_t)base + size);
13639 dvar->dtdv_next = next;
13640 dvar = next;
13641 }
13642
13643 if (maxper == 0)
13644 break;
13645 }
13646
13647 return (0);
13648 }
13649
13650 void
13651 dtrace_dstate_fini(dtrace_dstate_t *dstate)
13652 {
13653 ASSERT(MUTEX_HELD(&cpu_lock));
13654
13655 if (dstate->dtds_base == NULL)
13656 return;
13657
13658 kmem_free(dstate->dtds_base, dstate->dtds_size);
13659 kmem_cache_free(dtrace_state_cache, dstate->dtds_percpu);
13660 }
13661
13662 static void
13663 dtrace_vstate_fini(dtrace_vstate_t *vstate)
13664 {
13665 /*
13666 * Logical XOR, where are you?
13667 */
13668 ASSERT((vstate->dtvs_nglobals == 0) ^ (vstate->dtvs_globals != NULL));
13669
13670 if (vstate->dtvs_nglobals > 0) {
13671 kmem_free(vstate->dtvs_globals, vstate->dtvs_nglobals *
13672 sizeof (dtrace_statvar_t *));
13673 }
13674
13675 if (vstate->dtvs_ntlocals > 0) {
13676 kmem_free(vstate->dtvs_tlocals, vstate->dtvs_ntlocals *
13677 sizeof (dtrace_difv_t));
13678 }
13679
13680 ASSERT((vstate->dtvs_nlocals == 0) ^ (vstate->dtvs_locals != NULL));
13681
13682 if (vstate->dtvs_nlocals > 0) {
13683 kmem_free(vstate->dtvs_locals, vstate->dtvs_nlocals *
13684 sizeof (dtrace_statvar_t *));
13685 }
13686 }
13687
13688 static void
13689 dtrace_state_clean(dtrace_state_t *state)
13690 {
13691 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE)
13692 return;
13693
13694 dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars);
13695 dtrace_speculation_clean(state);
13696 }
13697
13698 static void
13699 dtrace_state_deadman(dtrace_state_t *state)
13700 {
13701 hrtime_t now;
13702
13703 dtrace_sync();
13704
13705 now = dtrace_gethrtime();
13706
13707 if (state != dtrace_anon.dta_state &&
13708 now - state->dts_laststatus >= dtrace_deadman_user)
13709 return;
13710
13711 /*
13712 * We must be sure that dts_alive never appears to be less than the
13713 * value upon entry to dtrace_state_deadman(), and because we lack a
13714 * dtrace_cas64(), we cannot store to it atomically. We thus instead
13715 * store INT64_MAX to it, followed by a memory barrier, followed by
13716 * the new value. This assures that dts_alive never appears to be
13717 * less than its true value, regardless of the order in which the
13718 * stores to the underlying storage are issued.
13719 */
13720 state->dts_alive = INT64_MAX;
13721 dtrace_membar_producer();
13722 state->dts_alive = now;
13723 }
13724
13725 dtrace_state_t *
13726 dtrace_state_create(dev_t *devp, cred_t *cr)
13727 {
13728 minor_t minor;
13729 major_t major;
13730 char c[30];
13731 dtrace_state_t *state;
13732 dtrace_optval_t *opt;
13733 int bufsize = NCPU * sizeof (dtrace_buffer_t), i;
13734
13735 ASSERT(MUTEX_HELD(&dtrace_lock));
13736 ASSERT(MUTEX_HELD(&cpu_lock));
13737
13738 minor = (minor_t)(uintptr_t)vmem_alloc(dtrace_minor, 1,
13739 VM_BESTFIT | VM_SLEEP);
13740
13741 if (ddi_soft_state_zalloc(dtrace_softstate, minor) != DDI_SUCCESS) {
13742 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
13743 return (NULL);
13744 }
13745
13746 state = ddi_get_soft_state(dtrace_softstate, minor);
13747 state->dts_epid = DTRACE_EPIDNONE + 1;
13748
13749 (void) snprintf(c, sizeof (c), "dtrace_aggid_%d", minor);
13750 state->dts_aggid_arena = vmem_create(c, (void *)1, UINT32_MAX, 1,
13751 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
13752
13753 if (devp != NULL) {
13754 major = getemajor(*devp);
13755 } else {
13756 major = ddi_driver_major(dtrace_devi);
13757 }
13758
13759 state->dts_dev = makedevice(major, minor);
13760
13761 if (devp != NULL)
13762 *devp = state->dts_dev;
13763
13764 /*
13765 * We allocate NCPU buffers. On the one hand, this can be quite
13766 * a bit of memory per instance (nearly 36K on a Starcat). On the
13767 * other hand, it saves an additional memory reference in the probe
13768 * path.
13769 */
13770 state->dts_buffer = kmem_zalloc(bufsize, KM_SLEEP);
13771 state->dts_aggbuffer = kmem_zalloc(bufsize, KM_SLEEP);
13772 state->dts_cleaner = CYCLIC_NONE;
13773 state->dts_deadman = CYCLIC_NONE;
13774 state->dts_vstate.dtvs_state = state;
13775
13776 for (i = 0; i < DTRACEOPT_MAX; i++)
13777 state->dts_options[i] = DTRACEOPT_UNSET;
13778
13779 /*
13780 * Set the default options.
13781 */
13782 opt = state->dts_options;
13783 opt[DTRACEOPT_BUFPOLICY] = DTRACEOPT_BUFPOLICY_SWITCH;
13784 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_AUTO;
13785 opt[DTRACEOPT_NSPEC] = dtrace_nspec_default;
13786 opt[DTRACEOPT_SPECSIZE] = dtrace_specsize_default;
13787 opt[DTRACEOPT_CPU] = (dtrace_optval_t)DTRACE_CPUALL;
13788 opt[DTRACEOPT_STRSIZE] = dtrace_strsize_default;
13789 opt[DTRACEOPT_STACKFRAMES] = dtrace_stackframes_default;
13790 opt[DTRACEOPT_USTACKFRAMES] = dtrace_ustackframes_default;
13791 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_default;
13792 opt[DTRACEOPT_AGGRATE] = dtrace_aggrate_default;
13793 opt[DTRACEOPT_SWITCHRATE] = dtrace_switchrate_default;
13794 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_default;
13795 opt[DTRACEOPT_JSTACKFRAMES] = dtrace_jstackframes_default;
13796 opt[DTRACEOPT_JSTACKSTRSIZE] = dtrace_jstackstrsize_default;
13797
13798 state->dts_activity = DTRACE_ACTIVITY_INACTIVE;
13799
13800 /*
13801 * Depending on the user credentials, we set flag bits which alter probe
13802 * visibility or the amount of destructiveness allowed. In the case of
13803 * actual anonymous tracing, or the possession of all privileges, all of
13804 * the normal checks are bypassed.
13805 */
13806 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
13807 state->dts_cred.dcr_visible = DTRACE_CRV_ALL;
13808 state->dts_cred.dcr_action = DTRACE_CRA_ALL;
13809 } else {
13810 /*
13811 * Set up the credentials for this instantiation. We take a
13812 * hold on the credential to prevent it from disappearing on
13813 * us; this in turn prevents the zone_t referenced by this
13814 * credential from disappearing. This means that we can
13815 * examine the credential and the zone from probe context.
13816 */
13817 crhold(cr);
13818 state->dts_cred.dcr_cred = cr;
13819
13820 /*
13821 * CRA_PROC means "we have *some* privilege for dtrace" and
13822 * unlocks the use of variables like pid, zonename, etc.
13823 */
13824 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE) ||
13825 PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
13826 state->dts_cred.dcr_action |= DTRACE_CRA_PROC;
13827 }
13828
13829 /*
13830 * dtrace_user allows use of syscall and profile providers.
13831 * If the user also has proc_owner and/or proc_zone, we
13832 * extend the scope to include additional visibility and
13833 * destructive power.
13834 */
13835 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) {
13836 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) {
13837 state->dts_cred.dcr_visible |=
13838 DTRACE_CRV_ALLPROC;
13839
13840 state->dts_cred.dcr_action |=
13841 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
13842 }
13843
13844 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) {
13845 state->dts_cred.dcr_visible |=
13846 DTRACE_CRV_ALLZONE;
13847
13848 state->dts_cred.dcr_action |=
13849 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
13850 }
13851
13852 /*
13853 * If we have all privs in whatever zone this is,
13854 * we can do destructive things to processes which
13855 * have altered credentials.
13856 */
13857 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
13858 cr->cr_zone->zone_privset)) {
13859 state->dts_cred.dcr_action |=
13860 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
13861 }
13862 }
13863
13864 /*
13865 * Holding the dtrace_kernel privilege also implies that
13866 * the user has the dtrace_user privilege from a visibility
13867 * perspective. But without further privileges, some
13868 * destructive actions are not available.
13869 */
13870 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) {
13871 /*
13872 * Make all probes in all zones visible. However,
13873 * this doesn't mean that all actions become available
13874 * to all zones.
13875 */
13876 state->dts_cred.dcr_visible |= DTRACE_CRV_KERNEL |
13877 DTRACE_CRV_ALLPROC | DTRACE_CRV_ALLZONE;
13878
13879 state->dts_cred.dcr_action |= DTRACE_CRA_KERNEL |
13880 DTRACE_CRA_PROC;
13881 /*
13882 * Holding proc_owner means that destructive actions
13883 * for *this* zone are allowed.
13884 */
13885 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
13886 state->dts_cred.dcr_action |=
13887 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
13888
13889 /*
13890 * Holding proc_zone means that destructive actions
13891 * for this user/group ID in all zones is allowed.
13892 */
13893 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
13894 state->dts_cred.dcr_action |=
13895 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
13896
13897 /*
13898 * If we have all privs in whatever zone this is,
13899 * we can do destructive things to processes which
13900 * have altered credentials.
13901 */
13902 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
13903 cr->cr_zone->zone_privset)) {
13904 state->dts_cred.dcr_action |=
13905 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
13906 }
13907 }
13908
13909 /*
13910 * Holding the dtrace_proc privilege gives control over fasttrap
13911 * and pid providers. We need to grant wider destructive
13912 * privileges in the event that the user has proc_owner and/or
13913 * proc_zone.
13914 */
13915 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
13916 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
13917 state->dts_cred.dcr_action |=
13918 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
13919
13920 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
13921 state->dts_cred.dcr_action |=
13922 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
13923 }
13924 }
13925
13926 return (state);
13927 }
13928
13929 static int
13930 dtrace_state_buffer(dtrace_state_t *state, dtrace_buffer_t *buf, int which)
13931 {
13932 dtrace_optval_t *opt = state->dts_options, size;
13933 processorid_t cpu;
13934 int flags = 0, rval, factor, divisor = 1;
13935
13936 ASSERT(MUTEX_HELD(&dtrace_lock));
13937 ASSERT(MUTEX_HELD(&cpu_lock));
13938 ASSERT(which < DTRACEOPT_MAX);
13939 ASSERT(state->dts_activity == DTRACE_ACTIVITY_INACTIVE ||
13940 (state == dtrace_anon.dta_state &&
13941 state->dts_activity == DTRACE_ACTIVITY_ACTIVE));
13942
13943 if (opt[which] == DTRACEOPT_UNSET || opt[which] == 0)
13944 return (0);
13945
13946 if (opt[DTRACEOPT_CPU] != DTRACEOPT_UNSET)
13947 cpu = opt[DTRACEOPT_CPU];
13948
13949 if (which == DTRACEOPT_SPECSIZE)
13950 flags |= DTRACEBUF_NOSWITCH;
13951
13952 if (which == DTRACEOPT_BUFSIZE) {
13953 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_RING)
13954 flags |= DTRACEBUF_RING;
13955
13956 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_FILL)
13957 flags |= DTRACEBUF_FILL;
13958
13959 if (state != dtrace_anon.dta_state ||
13960 state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
13961 flags |= DTRACEBUF_INACTIVE;
13962 }
13963
13964 for (size = opt[which]; size >= sizeof (uint64_t); size /= divisor) {
13965 /*
13966 * The size must be 8-byte aligned. If the size is not 8-byte
13967 * aligned, drop it down by the difference.
13968 */
13969 if (size & (sizeof (uint64_t) - 1))
13970 size -= size & (sizeof (uint64_t) - 1);
13971
13972 if (size < state->dts_reserve) {
13973 /*
13974 * Buffers always must be large enough to accommodate
13975 * their prereserved space. We return E2BIG instead
13976 * of ENOMEM in this case to allow for user-level
13977 * software to differentiate the cases.
13978 */
13979 return (E2BIG);
13980 }
13981
13982 rval = dtrace_buffer_alloc(buf, size, flags, cpu, &factor);
13983
13984 if (rval != ENOMEM) {
13985 opt[which] = size;
13986 return (rval);
13987 }
13988
13989 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
13990 return (rval);
13991
13992 for (divisor = 2; divisor < factor; divisor <<= 1)
13993 continue;
13994 }
13995
13996 return (ENOMEM);
13997 }
13998
13999 static int
14000 dtrace_state_buffers(dtrace_state_t *state)
14001 {
14002 dtrace_speculation_t *spec = state->dts_speculations;
14003 int rval, i;
14004
14005 if ((rval = dtrace_state_buffer(state, state->dts_buffer,
14006 DTRACEOPT_BUFSIZE)) != 0)
14007 return (rval);
14008
14009 if ((rval = dtrace_state_buffer(state, state->dts_aggbuffer,
14010 DTRACEOPT_AGGSIZE)) != 0)
14011 return (rval);
14012
14013 for (i = 0; i < state->dts_nspeculations; i++) {
14014 if ((rval = dtrace_state_buffer(state,
14015 spec[i].dtsp_buffer, DTRACEOPT_SPECSIZE)) != 0)
14016 return (rval);
14017 }
14018
14019 return (0);
14020 }
14021
14022 static void
14023 dtrace_state_prereserve(dtrace_state_t *state)
14024 {
14025 dtrace_ecb_t *ecb;
14026 dtrace_probe_t *probe;
14027
14028 state->dts_reserve = 0;
14029
14030 if (state->dts_options[DTRACEOPT_BUFPOLICY] != DTRACEOPT_BUFPOLICY_FILL)
14031 return;
14032
14033 /*
14034 * If our buffer policy is a "fill" buffer policy, we need to set the
14035 * prereserved space to be the space required by the END probes.
14036 */
14037 probe = dtrace_probes[dtrace_probeid_end - 1];
14038 ASSERT(probe != NULL);
14039
14040 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
14041 if (ecb->dte_state != state)
14042 continue;
14043
14044 state->dts_reserve += ecb->dte_needed + ecb->dte_alignment;
14045 }
14046 }
14047
14048 static int
14049 dtrace_state_go(dtrace_state_t *state, processorid_t *cpu)
14050 {
14051 dtrace_optval_t *opt = state->dts_options, sz, nspec;
14052 dtrace_speculation_t *spec;
14053 dtrace_buffer_t *buf;
14054 cyc_handler_t hdlr;
14055 cyc_time_t when;
14056 int rval = 0, i, bufsize = NCPU * sizeof (dtrace_buffer_t);
14057 dtrace_icookie_t cookie;
14058
14059 mutex_enter(&cpu_lock);
14060 mutex_enter(&dtrace_lock);
14061
14062 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
14063 rval = EBUSY;
14064 goto out;
14065 }
14066
14067 /*
14068 * Before we can perform any checks, we must prime all of the
14069 * retained enablings that correspond to this state.
14070 */
14071 dtrace_enabling_prime(state);
14072
14073 if (state->dts_destructive && !state->dts_cred.dcr_destructive) {
14074 rval = EACCES;
14075 goto out;
14076 }
14077
14078 dtrace_state_prereserve(state);
14079
14080 /*
14081 * Now we want to do is try to allocate our speculations.
14082 * We do not automatically resize the number of speculations; if
14083 * this fails, we will fail the operation.
14084 */
14085 nspec = opt[DTRACEOPT_NSPEC];
14086 ASSERT(nspec != DTRACEOPT_UNSET);
14087
14088 if (nspec > INT_MAX) {
14089 rval = ENOMEM;
14090 goto out;
14091 }
14092
14093 spec = kmem_zalloc(nspec * sizeof (dtrace_speculation_t),
14094 KM_NOSLEEP | KM_NORMALPRI);
14095
14096 if (spec == NULL) {
14097 rval = ENOMEM;
14098 goto out;
14099 }
14100
14101 state->dts_speculations = spec;
14102 state->dts_nspeculations = (int)nspec;
14103
14104 for (i = 0; i < nspec; i++) {
14105 if ((buf = kmem_zalloc(bufsize,
14106 KM_NOSLEEP | KM_NORMALPRI)) == NULL) {
14107 rval = ENOMEM;
14108 goto err;
14109 }
14110
14111 spec[i].dtsp_buffer = buf;
14112 }
14113
14114 if (opt[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET) {
14115 if (dtrace_anon.dta_state == NULL) {
14116 rval = ENOENT;
14117 goto out;
14118 }
14119
14120 if (state->dts_necbs != 0) {
14121 rval = EALREADY;
14122 goto out;
14123 }
14124
14125 state->dts_anon = dtrace_anon_grab();
14126 ASSERT(state->dts_anon != NULL);
14127 state = state->dts_anon;
14128
14129 /*
14130 * We want "grabanon" to be set in the grabbed state, so we'll
14131 * copy that option value from the grabbing state into the
14132 * grabbed state.
14133 */
14134 state->dts_options[DTRACEOPT_GRABANON] =
14135 opt[DTRACEOPT_GRABANON];
14136
14137 *cpu = dtrace_anon.dta_beganon;
14138
14139 /*
14140 * If the anonymous state is active (as it almost certainly
14141 * is if the anonymous enabling ultimately matched anything),
14142 * we don't allow any further option processing -- but we
14143 * don't return failure.
14144 */
14145 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
14146 goto out;
14147 }
14148
14149 if (opt[DTRACEOPT_AGGSIZE] != DTRACEOPT_UNSET &&
14150 opt[DTRACEOPT_AGGSIZE] != 0) {
14151 if (state->dts_aggregations == NULL) {
14152 /*
14153 * We're not going to create an aggregation buffer
14154 * because we don't have any ECBs that contain
14155 * aggregations -- set this option to 0.
14156 */
14157 opt[DTRACEOPT_AGGSIZE] = 0;
14158 } else {
14159 /*
14160 * If we have an aggregation buffer, we must also have
14161 * a buffer to use as scratch.
14162 */
14163 if (opt[DTRACEOPT_BUFSIZE] == DTRACEOPT_UNSET ||
14164 opt[DTRACEOPT_BUFSIZE] < state->dts_needed) {
14165 opt[DTRACEOPT_BUFSIZE] = state->dts_needed;
14166 }
14167 }
14168 }
14169
14170 if (opt[DTRACEOPT_SPECSIZE] != DTRACEOPT_UNSET &&
14171 opt[DTRACEOPT_SPECSIZE] != 0) {
14172 if (!state->dts_speculates) {
14173 /*
14174 * We're not going to create speculation buffers
14175 * because we don't have any ECBs that actually
14176 * speculate -- set the speculation size to 0.
14177 */
14178 opt[DTRACEOPT_SPECSIZE] = 0;
14179 }
14180 }
14181
14182 /*
14183 * The bare minimum size for any buffer that we're actually going to
14184 * do anything to is sizeof (uint64_t).
14185 */
14186 sz = sizeof (uint64_t);
14187
14188 if ((state->dts_needed != 0 && opt[DTRACEOPT_BUFSIZE] < sz) ||
14189 (state->dts_speculates && opt[DTRACEOPT_SPECSIZE] < sz) ||
14190 (state->dts_aggregations != NULL && opt[DTRACEOPT_AGGSIZE] < sz)) {
14191 /*
14192 * A buffer size has been explicitly set to 0 (or to a size
14193 * that will be adjusted to 0) and we need the space -- we
14194 * need to return failure. We return ENOSPC to differentiate
14195 * it from failing to allocate a buffer due to failure to meet
14196 * the reserve (for which we return E2BIG).
14197 */
14198 rval = ENOSPC;
14199 goto out;
14200 }
14201
14202 if ((rval = dtrace_state_buffers(state)) != 0)
14203 goto err;
14204
14205 if ((sz = opt[DTRACEOPT_DYNVARSIZE]) == DTRACEOPT_UNSET)
14206 sz = dtrace_dstate_defsize;
14207
14208 do {
14209 rval = dtrace_dstate_init(&state->dts_vstate.dtvs_dynvars, sz);
14210
14211 if (rval == 0)
14212 break;
14213
14214 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
14215 goto err;
14216 } while (sz >>= 1);
14217
14218 opt[DTRACEOPT_DYNVARSIZE] = sz;
14219
14220 if (rval != 0)
14221 goto err;
14222
14223 if (opt[DTRACEOPT_STATUSRATE] > dtrace_statusrate_max)
14224 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_max;
14225
14226 if (opt[DTRACEOPT_CLEANRATE] == 0)
14227 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
14228
14229 if (opt[DTRACEOPT_CLEANRATE] < dtrace_cleanrate_min)
14230 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_min;
14231
14232 if (opt[DTRACEOPT_CLEANRATE] > dtrace_cleanrate_max)
14233 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
14234
14235 hdlr.cyh_func = (cyc_func_t)dtrace_state_clean;
14236 hdlr.cyh_arg = state;
14237 hdlr.cyh_level = CY_LOW_LEVEL;
14238
14239 when.cyt_when = 0;
14240 when.cyt_interval = opt[DTRACEOPT_CLEANRATE];
14241
14242 state->dts_cleaner = cyclic_add(&hdlr, &when);
14243
14244 hdlr.cyh_func = (cyc_func_t)dtrace_state_deadman;
14245 hdlr.cyh_arg = state;
14246 hdlr.cyh_level = CY_LOW_LEVEL;
14247
14248 when.cyt_when = 0;
14249 when.cyt_interval = dtrace_deadman_interval;
14250
14251 state->dts_alive = state->dts_laststatus = dtrace_gethrtime();
14252 state->dts_deadman = cyclic_add(&hdlr, &when);
14253
14254 state->dts_activity = DTRACE_ACTIVITY_WARMUP;
14255
14256 if (state->dts_getf != 0 &&
14257 !(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)) {
14258 /*
14259 * We don't have kernel privs but we have at least one call
14260 * to getf(); we need to bump our zone's count, and (if
14261 * this is the first enabling to have an unprivileged call
14262 * to getf()) we need to hook into closef().
14263 */
14264 state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf++;
14265
14266 if (dtrace_getf++ == 0) {
14267 ASSERT(dtrace_closef == NULL);
14268 dtrace_closef = dtrace_getf_barrier;
14269 }
14270 }
14271
14272 /*
14273 * Now it's time to actually fire the BEGIN probe. We need to disable
14274 * interrupts here both to record the CPU on which we fired the BEGIN
14275 * probe (the data from this CPU will be processed first at user
14276 * level) and to manually activate the buffer for this CPU.
14277 */
14278 cookie = dtrace_interrupt_disable();
14279 *cpu = CPU->cpu_id;
14280 ASSERT(state->dts_buffer[*cpu].dtb_flags & DTRACEBUF_INACTIVE);
14281 state->dts_buffer[*cpu].dtb_flags &= ~DTRACEBUF_INACTIVE;
14282
14283 dtrace_probe(dtrace_probeid_begin,
14284 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
14285 dtrace_interrupt_enable(cookie);
14286 /*
14287 * We may have had an exit action from a BEGIN probe; only change our
14288 * state to ACTIVE if we're still in WARMUP.
14289 */
14290 ASSERT(state->dts_activity == DTRACE_ACTIVITY_WARMUP ||
14291 state->dts_activity == DTRACE_ACTIVITY_DRAINING);
14292
14293 if (state->dts_activity == DTRACE_ACTIVITY_WARMUP)
14294 state->dts_activity = DTRACE_ACTIVITY_ACTIVE;
14295
14296 /*
14297 * Regardless of whether or not now we're in ACTIVE or DRAINING, we
14298 * want each CPU to transition its principal buffer out of the
14299 * INACTIVE state. Doing this assures that no CPU will suddenly begin
14300 * processing an ECB halfway down a probe's ECB chain; all CPUs will
14301 * atomically transition from processing none of a state's ECBs to
14302 * processing all of them.
14303 */
14304 dtrace_xcall(DTRACE_CPUALL,
14305 (dtrace_xcall_t)dtrace_buffer_activate, state);
14306 goto out;
14307
14308 err:
14309 dtrace_buffer_free(state->dts_buffer);
14310 dtrace_buffer_free(state->dts_aggbuffer);
14311
14312 if ((nspec = state->dts_nspeculations) == 0) {
14313 ASSERT(state->dts_speculations == NULL);
14314 goto out;
14315 }
14316
14317 spec = state->dts_speculations;
14318 ASSERT(spec != NULL);
14319
14320 for (i = 0; i < state->dts_nspeculations; i++) {
14321 if ((buf = spec[i].dtsp_buffer) == NULL)
14322 break;
14323
14324 dtrace_buffer_free(buf);
14325 kmem_free(buf, bufsize);
14326 }
14327
14328 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
14329 state->dts_nspeculations = 0;
14330 state->dts_speculations = NULL;
14331
14332 out:
14333 mutex_exit(&dtrace_lock);
14334 mutex_exit(&cpu_lock);
14335
14336 return (rval);
14337 }
14338
14339 static int
14340 dtrace_state_stop(dtrace_state_t *state, processorid_t *cpu)
14341 {
14342 dtrace_icookie_t cookie;
14343
14344 ASSERT(MUTEX_HELD(&dtrace_lock));
14345
14346 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE &&
14347 state->dts_activity != DTRACE_ACTIVITY_DRAINING)
14348 return (EINVAL);
14349
14350 /*
14351 * We'll set the activity to DTRACE_ACTIVITY_DRAINING, and issue a sync
14352 * to be sure that every CPU has seen it. See below for the details
14353 * on why this is done.
14354 */
14355 state->dts_activity = DTRACE_ACTIVITY_DRAINING;
14356 dtrace_sync();
14357
14358 /*
14359 * By this point, it is impossible for any CPU to be still processing
14360 * with DTRACE_ACTIVITY_ACTIVE. We can thus set our activity to
14361 * DTRACE_ACTIVITY_COOLDOWN and know that we're not racing with any
14362 * other CPU in dtrace_buffer_reserve(). This allows dtrace_probe()
14363 * and callees to know that the activity is DTRACE_ACTIVITY_COOLDOWN
14364 * iff we're in the END probe.
14365 */
14366 state->dts_activity = DTRACE_ACTIVITY_COOLDOWN;
14367 dtrace_sync();
14368 ASSERT(state->dts_activity == DTRACE_ACTIVITY_COOLDOWN);
14369
14370 /*
14371 * Finally, we can release the reserve and call the END probe. We
14372 * disable interrupts across calling the END probe to allow us to
14373 * return the CPU on which we actually called the END probe. This
14374 * allows user-land to be sure that this CPU's principal buffer is
14375 * processed last.
14376 */
14377 state->dts_reserve = 0;
14378
14379 cookie = dtrace_interrupt_disable();
14380 *cpu = CPU->cpu_id;
14381 dtrace_probe(dtrace_probeid_end,
14382 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
14383 dtrace_interrupt_enable(cookie);
14384
14385 state->dts_activity = DTRACE_ACTIVITY_STOPPED;
14386 dtrace_sync();
14387
14388 if (state->dts_getf != 0 &&
14389 !(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)) {
14390 /*
14391 * We don't have kernel privs but we have at least one call
14392 * to getf(); we need to lower our zone's count, and (if
14393 * this is the last enabling to have an unprivileged call
14394 * to getf()) we need to clear the closef() hook.
14395 */
14396 ASSERT(state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf > 0);
14397 ASSERT(dtrace_closef == dtrace_getf_barrier);
14398 ASSERT(dtrace_getf > 0);
14399
14400 state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf--;
14401
14402 if (--dtrace_getf == 0)
14403 dtrace_closef = NULL;
14404 }
14405
14406 return (0);
14407 }
14408
14409 static int
14410 dtrace_state_option(dtrace_state_t *state, dtrace_optid_t option,
14411 dtrace_optval_t val)
14412 {
14413 ASSERT(MUTEX_HELD(&dtrace_lock));
14414
14415 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
14416 return (EBUSY);
14417
14418 if (option >= DTRACEOPT_MAX)
14419 return (EINVAL);
14420
14421 if (option != DTRACEOPT_CPU && val < 0)
14422 return (EINVAL);
14423
14424 switch (option) {
14425 case DTRACEOPT_DESTRUCTIVE:
14426 if (dtrace_destructive_disallow)
14427 return (EACCES);
14428
14429 state->dts_cred.dcr_destructive = 1;
14430 break;
14431
14432 case DTRACEOPT_BUFSIZE:
14433 case DTRACEOPT_DYNVARSIZE:
14434 case DTRACEOPT_AGGSIZE:
14435 case DTRACEOPT_SPECSIZE:
14436 case DTRACEOPT_STRSIZE:
14437 if (val < 0)
14438 return (EINVAL);
14439
14440 if (val >= LONG_MAX) {
14441 /*
14442 * If this is an otherwise negative value, set it to
14443 * the highest multiple of 128m less than LONG_MAX.
14444 * Technically, we're adjusting the size without
14445 * regard to the buffer resizing policy, but in fact,
14446 * this has no effect -- if we set the buffer size to
14447 * ~LONG_MAX and the buffer policy is ultimately set to
14448 * be "manual", the buffer allocation is guaranteed to
14449 * fail, if only because the allocation requires two
14450 * buffers. (We set the the size to the highest
14451 * multiple of 128m because it ensures that the size
14452 * will remain a multiple of a megabyte when
14453 * repeatedly halved -- all the way down to 15m.)
14454 */
14455 val = LONG_MAX - (1 << 27) + 1;
14456 }
14457 }
14458
14459 state->dts_options[option] = val;
14460
14461 return (0);
14462 }
14463
14464 static void
14465 dtrace_state_destroy(dtrace_state_t *state)
14466 {
14467 dtrace_ecb_t *ecb;
14468 dtrace_vstate_t *vstate = &state->dts_vstate;
14469 minor_t minor = getminor(state->dts_dev);
14470 int i, bufsize = NCPU * sizeof (dtrace_buffer_t);
14471 dtrace_speculation_t *spec = state->dts_speculations;
14472 int nspec = state->dts_nspeculations;
14473 uint32_t match;
14474
14475 ASSERT(MUTEX_HELD(&dtrace_lock));
14476 ASSERT(MUTEX_HELD(&cpu_lock));
14477
14478 /*
14479 * First, retract any retained enablings for this state.
14480 */
14481 dtrace_enabling_retract(state);
14482 ASSERT(state->dts_nretained == 0);
14483
14484 if (state->dts_activity == DTRACE_ACTIVITY_ACTIVE ||
14485 state->dts_activity == DTRACE_ACTIVITY_DRAINING) {
14486 /*
14487 * We have managed to come into dtrace_state_destroy() on a
14488 * hot enabling -- almost certainly because of a disorderly
14489 * shutdown of a consumer. (That is, a consumer that is
14490 * exiting without having called dtrace_stop().) In this case,
14491 * we're going to set our activity to be KILLED, and then
14492 * issue a sync to be sure that everyone is out of probe
14493 * context before we start blowing away ECBs.
14494 */
14495 state->dts_activity = DTRACE_ACTIVITY_KILLED;
14496 dtrace_sync();
14497 }
14498
14499 /*
14500 * Release the credential hold we took in dtrace_state_create().
14501 */
14502 if (state->dts_cred.dcr_cred != NULL)
14503 crfree(state->dts_cred.dcr_cred);
14504
14505 /*
14506 * Now we can safely disable and destroy any enabled probes. Because
14507 * any DTRACE_PRIV_KERNEL probes may actually be slowing our progress
14508 * (especially if they're all enabled), we take two passes through the
14509 * ECBs: in the first, we disable just DTRACE_PRIV_KERNEL probes, and
14510 * in the second we disable whatever is left over.
14511 */
14512 for (match = DTRACE_PRIV_KERNEL; ; match = 0) {
14513 for (i = 0; i < state->dts_necbs; i++) {
14514 if ((ecb = state->dts_ecbs[i]) == NULL)
14515 continue;
14516
14517 if (match && ecb->dte_probe != NULL) {
14518 dtrace_probe_t *probe = ecb->dte_probe;
14519 dtrace_provider_t *prov = probe->dtpr_provider;
14520
14521 if (!(prov->dtpv_priv.dtpp_flags & match))
14522 continue;
14523 }
14524
14525 dtrace_ecb_disable(ecb);
14526 dtrace_ecb_destroy(ecb);
14527 }
14528
14529 if (!match)
14530 break;
14531 }
14532
14533 /*
14534 * Before we free the buffers, perform one more sync to assure that
14535 * every CPU is out of probe context.
14536 */
14537 dtrace_sync();
14538
14539 dtrace_buffer_free(state->dts_buffer);
14540 dtrace_buffer_free(state->dts_aggbuffer);
14541
14542 for (i = 0; i < nspec; i++)
14543 dtrace_buffer_free(spec[i].dtsp_buffer);
14544
14545 if (state->dts_cleaner != CYCLIC_NONE)
14546 cyclic_remove(state->dts_cleaner);
14547
14548 if (state->dts_deadman != CYCLIC_NONE)
14549 cyclic_remove(state->dts_deadman);
14550
14551 dtrace_dstate_fini(&vstate->dtvs_dynvars);
14552 dtrace_vstate_fini(vstate);
14553 kmem_free(state->dts_ecbs, state->dts_necbs * sizeof (dtrace_ecb_t *));
14554
14555 if (state->dts_aggregations != NULL) {
14556 #ifdef DEBUG
14557 for (i = 0; i < state->dts_naggregations; i++)
14558 ASSERT(state->dts_aggregations[i] == NULL);
14559 #endif
14560 ASSERT(state->dts_naggregations > 0);
14561 kmem_free(state->dts_aggregations,
14562 state->dts_naggregations * sizeof (dtrace_aggregation_t *));
14563 }
14564
14565 kmem_free(state->dts_buffer, bufsize);
14566 kmem_free(state->dts_aggbuffer, bufsize);
14567
14568 for (i = 0; i < nspec; i++)
14569 kmem_free(spec[i].dtsp_buffer, bufsize);
14570
14571 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
14572
14573 dtrace_format_destroy(state);
14574
14575 vmem_destroy(state->dts_aggid_arena);
14576 ddi_soft_state_free(dtrace_softstate, minor);
14577 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
14578 }
14579
14580 /*
14581 * DTrace Anonymous Enabling Functions
14582 */
14583 static dtrace_state_t *
14584 dtrace_anon_grab(void)
14585 {
14586 dtrace_state_t *state;
14587
14588 ASSERT(MUTEX_HELD(&dtrace_lock));
14589
14590 if ((state = dtrace_anon.dta_state) == NULL) {
14591 ASSERT(dtrace_anon.dta_enabling == NULL);
14592 return (NULL);
14593 }
14594
14595 ASSERT(dtrace_anon.dta_enabling != NULL);
14596 ASSERT(dtrace_retained != NULL);
14597
14598 dtrace_enabling_destroy(dtrace_anon.dta_enabling);
14599 dtrace_anon.dta_enabling = NULL;
14600 dtrace_anon.dta_state = NULL;
14601
14602 return (state);
14603 }
14604
14605 static void
14606 dtrace_anon_property(void)
14607 {
14608 int i, rv;
14609 dtrace_state_t *state;
14610 dof_hdr_t *dof;
14611 char c[32]; /* enough for "dof-data-" + digits */
14612
14613 ASSERT(MUTEX_HELD(&dtrace_lock));
14614 ASSERT(MUTEX_HELD(&cpu_lock));
14615
14616 for (i = 0; ; i++) {
14617 (void) snprintf(c, sizeof (c), "dof-data-%d", i);
14618
14619 dtrace_err_verbose = 1;
14620
14621 if ((dof = dtrace_dof_property(c)) == NULL) {
14622 dtrace_err_verbose = 0;
14623 break;
14624 }
14625
14626 /*
14627 * We want to create anonymous state, so we need to transition
14628 * the kernel debugger to indicate that DTrace is active. If
14629 * this fails (e.g. because the debugger has modified text in
14630 * some way), we won't continue with the processing.
14631 */
14632 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
14633 cmn_err(CE_NOTE, "kernel debugger active; anonymous "
14634 "enabling ignored.");
14635 dtrace_dof_destroy(dof);
14636 break;
14637 }
14638
14639 /*
14640 * If we haven't allocated an anonymous state, we'll do so now.
14641 */
14642 if ((state = dtrace_anon.dta_state) == NULL) {
14643 state = dtrace_state_create(NULL, NULL);
14644 dtrace_anon.dta_state = state;
14645
14646 if (state == NULL) {
14647 /*
14648 * This basically shouldn't happen: the only
14649 * failure mode from dtrace_state_create() is a
14650 * failure of ddi_soft_state_zalloc() that
14651 * itself should never happen. Still, the
14652 * interface allows for a failure mode, and
14653 * we want to fail as gracefully as possible:
14654 * we'll emit an error message and cease
14655 * processing anonymous state in this case.
14656 */
14657 cmn_err(CE_WARN, "failed to create "
14658 "anonymous state");
14659 dtrace_dof_destroy(dof);
14660 break;
14661 }
14662 }
14663
14664 rv = dtrace_dof_slurp(dof, &state->dts_vstate, CRED(),
14665 &dtrace_anon.dta_enabling, 0, B_TRUE);
14666
14667 if (rv == 0)
14668 rv = dtrace_dof_options(dof, state);
14669
14670 dtrace_err_verbose = 0;
14671 dtrace_dof_destroy(dof);
14672
14673 if (rv != 0) {
14674 /*
14675 * This is malformed DOF; chuck any anonymous state
14676 * that we created.
14677 */
14678 ASSERT(dtrace_anon.dta_enabling == NULL);
14679 dtrace_state_destroy(state);
14680 dtrace_anon.dta_state = NULL;
14681 break;
14682 }
14683
14684 ASSERT(dtrace_anon.dta_enabling != NULL);
14685 }
14686
14687 if (dtrace_anon.dta_enabling != NULL) {
14688 int rval;
14689
14690 /*
14691 * dtrace_enabling_retain() can only fail because we are
14692 * trying to retain more enablings than are allowed -- but
14693 * we only have one anonymous enabling, and we are guaranteed
14694 * to be allowed at least one retained enabling; we assert
14695 * that dtrace_enabling_retain() returns success.
14696 */
14697 rval = dtrace_enabling_retain(dtrace_anon.dta_enabling);
14698 ASSERT(rval == 0);
14699
14700 dtrace_enabling_dump(dtrace_anon.dta_enabling);
14701 }
14702 }
14703
14704 /*
14705 * DTrace Helper Functions
14706 */
14707 static void
14708 dtrace_helper_trace(dtrace_helper_action_t *helper,
14709 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, int where)
14710 {
14711 uint32_t size, next, nnext, i;
14712 dtrace_helptrace_t *ent, *buffer;
14713 uint16_t flags = cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
14714
14715 if ((buffer = dtrace_helptrace_buffer) == NULL)
14716 return;
14717
14718 ASSERT(vstate->dtvs_nlocals <= dtrace_helptrace_nlocals);
14719
14720 /*
14721 * What would a tracing framework be without its own tracing
14722 * framework? (Well, a hell of a lot simpler, for starters...)
14723 */
14724 size = sizeof (dtrace_helptrace_t) + dtrace_helptrace_nlocals *
14725 sizeof (uint64_t) - sizeof (uint64_t);
14726
14727 /*
14728 * Iterate until we can allocate a slot in the trace buffer.
14729 */
14730 do {
14731 next = dtrace_helptrace_next;
14732
14733 if (next + size < dtrace_helptrace_bufsize) {
14734 nnext = next + size;
14735 } else {
14736 nnext = size;
14737 }
14738 } while (dtrace_cas32(&dtrace_helptrace_next, next, nnext) != next);
14739
14740 /*
14741 * We have our slot; fill it in.
14742 */
14743 if (nnext == size) {
14744 dtrace_helptrace_wrapped++;
14745 next = 0;
14746 }
14747
14748 ent = (dtrace_helptrace_t *)((uintptr_t)buffer + next);
14749 ent->dtht_helper = helper;
14750 ent->dtht_where = where;
14751 ent->dtht_nlocals = vstate->dtvs_nlocals;
14752
14753 ent->dtht_fltoffs = (mstate->dtms_present & DTRACE_MSTATE_FLTOFFS) ?
14754 mstate->dtms_fltoffs : -1;
14755 ent->dtht_fault = DTRACE_FLAGS2FLT(flags);
14756 ent->dtht_illval = cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
14757
14758 for (i = 0; i < vstate->dtvs_nlocals; i++) {
14759 dtrace_statvar_t *svar;
14760
14761 if ((svar = vstate->dtvs_locals[i]) == NULL)
14762 continue;
14763
14764 ASSERT(svar->dtsv_size >= NCPU * sizeof (uint64_t));
14765 ent->dtht_locals[i] =
14766 ((uint64_t *)(uintptr_t)svar->dtsv_data)[CPU->cpu_id];
14767 }
14768 }
14769
14770 static uint64_t
14771 dtrace_helper(int which, dtrace_mstate_t *mstate,
14772 dtrace_state_t *state, uint64_t arg0, uint64_t arg1)
14773 {
14774 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
14775 uint64_t sarg0 = mstate->dtms_arg[0];
14776 uint64_t sarg1 = mstate->dtms_arg[1];
14777 uint64_t rval;
14778 dtrace_helpers_t *helpers = curproc->p_dtrace_helpers;
14779 dtrace_helper_action_t *helper;
14780 dtrace_vstate_t *vstate;
14781 dtrace_difo_t *pred;
14782 int i, trace = dtrace_helptrace_buffer != NULL;
14783
14784 ASSERT(which >= 0 && which < DTRACE_NHELPER_ACTIONS);
14785
14786 if (helpers == NULL)
14787 return (0);
14788
14789 if ((helper = helpers->dthps_actions[which]) == NULL)
14790 return (0);
14791
14792 vstate = &helpers->dthps_vstate;
14793 mstate->dtms_arg[0] = arg0;
14794 mstate->dtms_arg[1] = arg1;
14795
14796 /*
14797 * Now iterate over each helper. If its predicate evaluates to 'true',
14798 * we'll call the corresponding actions. Note that the below calls
14799 * to dtrace_dif_emulate() may set faults in machine state. This is
14800 * okay: our caller (the outer dtrace_dif_emulate()) will simply plow
14801 * the stored DIF offset with its own (which is the desired behavior).
14802 * Also, note the calls to dtrace_dif_emulate() may allocate scratch
14803 * from machine state; this is okay, too.
14804 */
14805 for (; helper != NULL; helper = helper->dtha_next) {
14806 if ((pred = helper->dtha_predicate) != NULL) {
14807 if (trace)
14808 dtrace_helper_trace(helper, mstate, vstate, 0);
14809
14810 if (!dtrace_dif_emulate(pred, mstate, vstate, state))
14811 goto next;
14812
14813 if (*flags & CPU_DTRACE_FAULT)
14814 goto err;
14815 }
14816
14817 for (i = 0; i < helper->dtha_nactions; i++) {
14818 if (trace)
14819 dtrace_helper_trace(helper,
14820 mstate, vstate, i + 1);
14821
14822 rval = dtrace_dif_emulate(helper->dtha_actions[i],
14823 mstate, vstate, state);
14824
14825 if (*flags & CPU_DTRACE_FAULT)
14826 goto err;
14827 }
14828
14829 next:
14830 if (trace)
14831 dtrace_helper_trace(helper, mstate, vstate,
14832 DTRACE_HELPTRACE_NEXT);
14833 }
14834
14835 if (trace)
14836 dtrace_helper_trace(helper, mstate, vstate,
14837 DTRACE_HELPTRACE_DONE);
14838
14839 /*
14840 * Restore the arg0 that we saved upon entry.
14841 */
14842 mstate->dtms_arg[0] = sarg0;
14843 mstate->dtms_arg[1] = sarg1;
14844
14845 return (rval);
14846
14847 err:
14848 if (trace)
14849 dtrace_helper_trace(helper, mstate, vstate,
14850 DTRACE_HELPTRACE_ERR);
14851
14852 /*
14853 * Restore the arg0 that we saved upon entry.
14854 */
14855 mstate->dtms_arg[0] = sarg0;
14856 mstate->dtms_arg[1] = sarg1;
14857
14858 return (0);
14859 }
14860
14861 static void
14862 dtrace_helper_action_destroy(dtrace_helper_action_t *helper,
14863 dtrace_vstate_t *vstate)
14864 {
14865 int i;
14866
14867 if (helper->dtha_predicate != NULL)
14868 dtrace_difo_release(helper->dtha_predicate, vstate);
14869
14870 for (i = 0; i < helper->dtha_nactions; i++) {
14871 ASSERT(helper->dtha_actions[i] != NULL);
14872 dtrace_difo_release(helper->dtha_actions[i], vstate);
14873 }
14874
14875 kmem_free(helper->dtha_actions,
14876 helper->dtha_nactions * sizeof (dtrace_difo_t *));
14877 kmem_free(helper, sizeof (dtrace_helper_action_t));
14878 }
14879
14880 static int
14881 dtrace_helper_destroygen(int gen)
14882 {
14883 proc_t *p = curproc;
14884 dtrace_helpers_t *help = p->p_dtrace_helpers;
14885 dtrace_vstate_t *vstate;
14886 int i;
14887
14888 ASSERT(MUTEX_HELD(&dtrace_lock));
14889
14890 if (help == NULL || gen > help->dthps_generation)
14891 return (EINVAL);
14892
14893 vstate = &help->dthps_vstate;
14894
14895 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
14896 dtrace_helper_action_t *last = NULL, *h, *next;
14897
14898 for (h = help->dthps_actions[i]; h != NULL; h = next) {
14899 next = h->dtha_next;
14900
14901 if (h->dtha_generation == gen) {
14902 if (last != NULL) {
14903 last->dtha_next = next;
14904 } else {
14905 help->dthps_actions[i] = next;
14906 }
14907
14908 dtrace_helper_action_destroy(h, vstate);
14909 } else {
14910 last = h;
14911 }
14912 }
14913 }
14914
14915 /*
14916 * Interate until we've cleared out all helper providers with the
14917 * given generation number.
14918 */
14919 for (;;) {
14920 dtrace_helper_provider_t *prov;
14921
14922 /*
14923 * Look for a helper provider with the right generation. We
14924 * have to start back at the beginning of the list each time
14925 * because we drop dtrace_lock. It's unlikely that we'll make
14926 * more than two passes.
14927 */
14928 for (i = 0; i < help->dthps_nprovs; i++) {
14929 prov = help->dthps_provs[i];
14930
14931 if (prov->dthp_generation == gen)
14932 break;
14933 }
14934
14935 /*
14936 * If there were no matches, we're done.
14937 */
14938 if (i == help->dthps_nprovs)
14939 break;
14940
14941 /*
14942 * Move the last helper provider into this slot.
14943 */
14944 help->dthps_nprovs--;
14945 help->dthps_provs[i] = help->dthps_provs[help->dthps_nprovs];
14946 help->dthps_provs[help->dthps_nprovs] = NULL;
14947
14948 mutex_exit(&dtrace_lock);
14949
14950 /*
14951 * If we have a meta provider, remove this helper provider.
14952 */
14953 mutex_enter(&dtrace_meta_lock);
14954 if (dtrace_meta_pid != NULL) {
14955 ASSERT(dtrace_deferred_pid == NULL);
14956 dtrace_helper_provider_remove(&prov->dthp_prov,
14957 p->p_pid);
14958 }
14959 mutex_exit(&dtrace_meta_lock);
14960
14961 dtrace_helper_provider_destroy(prov);
14962
14963 mutex_enter(&dtrace_lock);
14964 }
14965
14966 return (0);
14967 }
14968
14969 static int
14970 dtrace_helper_validate(dtrace_helper_action_t *helper)
14971 {
14972 int err = 0, i;
14973 dtrace_difo_t *dp;
14974
14975 if ((dp = helper->dtha_predicate) != NULL)
14976 err += dtrace_difo_validate_helper(dp);
14977
14978 for (i = 0; i < helper->dtha_nactions; i++)
14979 err += dtrace_difo_validate_helper(helper->dtha_actions[i]);
14980
14981 return (err == 0);
14982 }
14983
14984 static int
14985 dtrace_helper_action_add(int which, dtrace_ecbdesc_t *ep)
14986 {
14987 dtrace_helpers_t *help;
14988 dtrace_helper_action_t *helper, *last;
14989 dtrace_actdesc_t *act;
14990 dtrace_vstate_t *vstate;
14991 dtrace_predicate_t *pred;
14992 int count = 0, nactions = 0, i;
14993
14994 if (which < 0 || which >= DTRACE_NHELPER_ACTIONS)
14995 return (EINVAL);
14996
14997 help = curproc->p_dtrace_helpers;
14998 last = help->dthps_actions[which];
14999 vstate = &help->dthps_vstate;
15000
15001 for (count = 0; last != NULL; last = last->dtha_next) {
15002 count++;
15003 if (last->dtha_next == NULL)
15004 break;
15005 }
15006
15007 /*
15008 * If we already have dtrace_helper_actions_max helper actions for this
15009 * helper action type, we'll refuse to add a new one.
15010 */
15011 if (count >= dtrace_helper_actions_max)
15012 return (ENOSPC);
15013
15014 helper = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP);
15015 helper->dtha_generation = help->dthps_generation;
15016
15017 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) {
15018 ASSERT(pred->dtp_difo != NULL);
15019 dtrace_difo_hold(pred->dtp_difo);
15020 helper->dtha_predicate = pred->dtp_difo;
15021 }
15022
15023 for (act = ep->dted_action; act != NULL; act = act->dtad_next) {
15024 if (act->dtad_kind != DTRACEACT_DIFEXPR)
15025 goto err;
15026
15027 if (act->dtad_difo == NULL)
15028 goto err;
15029
15030 nactions++;
15031 }
15032
15033 helper->dtha_actions = kmem_zalloc(sizeof (dtrace_difo_t *) *
15034 (helper->dtha_nactions = nactions), KM_SLEEP);
15035
15036 for (act = ep->dted_action, i = 0; act != NULL; act = act->dtad_next) {
15037 dtrace_difo_hold(act->dtad_difo);
15038 helper->dtha_actions[i++] = act->dtad_difo;
15039 }
15040
15041 if (!dtrace_helper_validate(helper))
15042 goto err;
15043
15044 if (last == NULL) {
15045 help->dthps_actions[which] = helper;
15046 } else {
15047 last->dtha_next = helper;
15048 }
15049
15050 if (vstate->dtvs_nlocals > dtrace_helptrace_nlocals) {
15051 dtrace_helptrace_nlocals = vstate->dtvs_nlocals;
15052 dtrace_helptrace_next = 0;
15053 }
15054
15055 return (0);
15056 err:
15057 dtrace_helper_action_destroy(helper, vstate);
15058 return (EINVAL);
15059 }
15060
15061 static void
15062 dtrace_helper_provider_register(proc_t *p, dtrace_helpers_t *help,
15063 dof_helper_t *dofhp)
15064 {
15065 ASSERT(MUTEX_NOT_HELD(&dtrace_lock));
15066
15067 mutex_enter(&dtrace_meta_lock);
15068 mutex_enter(&dtrace_lock);
15069
15070 if (!dtrace_attached() || dtrace_meta_pid == NULL) {
15071 /*
15072 * If the dtrace module is loaded but not attached, or if
15073 * there aren't isn't a meta provider registered to deal with
15074 * these provider descriptions, we need to postpone creating
15075 * the actual providers until later.
15076 */
15077
15078 if (help->dthps_next == NULL && help->dthps_prev == NULL &&
15079 dtrace_deferred_pid != help) {
15080 help->dthps_deferred = 1;
15081 help->dthps_pid = p->p_pid;
15082 help->dthps_next = dtrace_deferred_pid;
15083 help->dthps_prev = NULL;
15084 if (dtrace_deferred_pid != NULL)
15085 dtrace_deferred_pid->dthps_prev = help;
15086 dtrace_deferred_pid = help;
15087 }
15088
15089 mutex_exit(&dtrace_lock);
15090
15091 } else if (dofhp != NULL) {
15092 /*
15093 * If the dtrace module is loaded and we have a particular
15094 * helper provider description, pass that off to the
15095 * meta provider.
15096 */
15097
15098 mutex_exit(&dtrace_lock);
15099
15100 dtrace_helper_provide(dofhp, p->p_pid);
15101
15102 } else {
15103 /*
15104 * Otherwise, just pass all the helper provider descriptions
15105 * off to the meta provider.
15106 */
15107
15108 int i;
15109 mutex_exit(&dtrace_lock);
15110
15111 for (i = 0; i < help->dthps_nprovs; i++) {
15112 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
15113 p->p_pid);
15114 }
15115 }
15116
15117 mutex_exit(&dtrace_meta_lock);
15118 }
15119
15120 static int
15121 dtrace_helper_provider_add(dof_helper_t *dofhp, int gen)
15122 {
15123 dtrace_helpers_t *help;
15124 dtrace_helper_provider_t *hprov, **tmp_provs;
15125 uint_t tmp_maxprovs, i;
15126
15127 ASSERT(MUTEX_HELD(&dtrace_lock));
15128
15129 help = curproc->p_dtrace_helpers;
15130 ASSERT(help != NULL);
15131
15132 /*
15133 * If we already have dtrace_helper_providers_max helper providers,
15134 * we're refuse to add a new one.
15135 */
15136 if (help->dthps_nprovs >= dtrace_helper_providers_max)
15137 return (ENOSPC);
15138
15139 /*
15140 * Check to make sure this isn't a duplicate.
15141 */
15142 for (i = 0; i < help->dthps_nprovs; i++) {
15143 if (dofhp->dofhp_addr ==
15144 help->dthps_provs[i]->dthp_prov.dofhp_addr)
15145 return (EALREADY);
15146 }
15147
15148 hprov = kmem_zalloc(sizeof (dtrace_helper_provider_t), KM_SLEEP);
15149 hprov->dthp_prov = *dofhp;
15150 hprov->dthp_ref = 1;
15151 hprov->dthp_generation = gen;
15152
15153 /*
15154 * Allocate a bigger table for helper providers if it's already full.
15155 */
15156 if (help->dthps_maxprovs == help->dthps_nprovs) {
15157 tmp_maxprovs = help->dthps_maxprovs;
15158 tmp_provs = help->dthps_provs;
15159
15160 if (help->dthps_maxprovs == 0)
15161 help->dthps_maxprovs = 2;
15162 else
15163 help->dthps_maxprovs *= 2;
15164 if (help->dthps_maxprovs > dtrace_helper_providers_max)
15165 help->dthps_maxprovs = dtrace_helper_providers_max;
15166
15167 ASSERT(tmp_maxprovs < help->dthps_maxprovs);
15168
15169 help->dthps_provs = kmem_zalloc(help->dthps_maxprovs *
15170 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
15171
15172 if (tmp_provs != NULL) {
15173 bcopy(tmp_provs, help->dthps_provs, tmp_maxprovs *
15174 sizeof (dtrace_helper_provider_t *));
15175 kmem_free(tmp_provs, tmp_maxprovs *
15176 sizeof (dtrace_helper_provider_t *));
15177 }
15178 }
15179
15180 help->dthps_provs[help->dthps_nprovs] = hprov;
15181 help->dthps_nprovs++;
15182
15183 return (0);
15184 }
15185
15186 static void
15187 dtrace_helper_provider_destroy(dtrace_helper_provider_t *hprov)
15188 {
15189 mutex_enter(&dtrace_lock);
15190
15191 if (--hprov->dthp_ref == 0) {
15192 dof_hdr_t *dof;
15193 mutex_exit(&dtrace_lock);
15194 dof = (dof_hdr_t *)(uintptr_t)hprov->dthp_prov.dofhp_dof;
15195 dtrace_dof_destroy(dof);
15196 kmem_free(hprov, sizeof (dtrace_helper_provider_t));
15197 } else {
15198 mutex_exit(&dtrace_lock);
15199 }
15200 }
15201
15202 static int
15203 dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec)
15204 {
15205 uintptr_t daddr = (uintptr_t)dof;
15206 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
15207 dof_provider_t *provider;
15208 dof_probe_t *probe;
15209 uint8_t *arg;
15210 char *strtab, *typestr;
15211 dof_stridx_t typeidx;
15212 size_t typesz;
15213 uint_t nprobes, j, k;
15214
15215 ASSERT(sec->dofs_type == DOF_SECT_PROVIDER);
15216
15217 if (sec->dofs_offset & (sizeof (uint_t) - 1)) {
15218 dtrace_dof_error(dof, "misaligned section offset");
15219 return (-1);
15220 }
15221
15222 /*
15223 * The section needs to be large enough to contain the DOF provider
15224 * structure appropriate for the given version.
15225 */
15226 if (sec->dofs_size <
15227 ((dof->dofh_ident[DOF_ID_VERSION] == DOF_VERSION_1) ?
15228 offsetof(dof_provider_t, dofpv_prenoffs) :
15229 sizeof (dof_provider_t))) {
15230 dtrace_dof_error(dof, "provider section too small");
15231 return (-1);
15232 }
15233
15234 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
15235 str_sec = dtrace_dof_sect(dof, DOF_SECT_STRTAB, provider->dofpv_strtab);
15236 prb_sec = dtrace_dof_sect(dof, DOF_SECT_PROBES, provider->dofpv_probes);
15237 arg_sec = dtrace_dof_sect(dof, DOF_SECT_PRARGS, provider->dofpv_prargs);
15238 off_sec = dtrace_dof_sect(dof, DOF_SECT_PROFFS, provider->dofpv_proffs);
15239
15240 if (str_sec == NULL || prb_sec == NULL ||
15241 arg_sec == NULL || off_sec == NULL)
15242 return (-1);
15243
15244 enoff_sec = NULL;
15245
15246 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
15247 provider->dofpv_prenoffs != DOF_SECT_NONE &&
15248 (enoff_sec = dtrace_dof_sect(dof, DOF_SECT_PRENOFFS,
15249 provider->dofpv_prenoffs)) == NULL)
15250 return (-1);
15251
15252 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
15253
15254 if (provider->dofpv_name >= str_sec->dofs_size ||
15255 strlen(strtab + provider->dofpv_name) >= DTRACE_PROVNAMELEN) {
15256 dtrace_dof_error(dof, "invalid provider name");
15257 return (-1);
15258 }
15259
15260 if (prb_sec->dofs_entsize == 0 ||
15261 prb_sec->dofs_entsize > prb_sec->dofs_size) {
15262 dtrace_dof_error(dof, "invalid entry size");
15263 return (-1);
15264 }
15265
15266 if (prb_sec->dofs_entsize & (sizeof (uintptr_t) - 1)) {
15267 dtrace_dof_error(dof, "misaligned entry size");
15268 return (-1);
15269 }
15270
15271 if (off_sec->dofs_entsize != sizeof (uint32_t)) {
15272 dtrace_dof_error(dof, "invalid entry size");
15273 return (-1);
15274 }
15275
15276 if (off_sec->dofs_offset & (sizeof (uint32_t) - 1)) {
15277 dtrace_dof_error(dof, "misaligned section offset");
15278 return (-1);
15279 }
15280
15281 if (arg_sec->dofs_entsize != sizeof (uint8_t)) {
15282 dtrace_dof_error(dof, "invalid entry size");
15283 return (-1);
15284 }
15285
15286 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
15287
15288 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
15289
15290 /*
15291 * Take a pass through the probes to check for errors.
15292 */
15293 for (j = 0; j < nprobes; j++) {
15294 probe = (dof_probe_t *)(uintptr_t)(daddr +
15295 prb_sec->dofs_offset + j * prb_sec->dofs_entsize);
15296
15297 if (probe->dofpr_func >= str_sec->dofs_size) {
15298 dtrace_dof_error(dof, "invalid function name");
15299 return (-1);
15300 }
15301
15302 if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) {
15303 dtrace_dof_error(dof, "function name too long");
15304 return (-1);
15305 }
15306
15307 if (probe->dofpr_name >= str_sec->dofs_size ||
15308 strlen(strtab + probe->dofpr_name) >= DTRACE_NAMELEN) {
15309 dtrace_dof_error(dof, "invalid probe name");
15310 return (-1);
15311 }
15312
15313 /*
15314 * The offset count must not wrap the index, and the offsets
15315 * must also not overflow the section's data.
15316 */
15317 if (probe->dofpr_offidx + probe->dofpr_noffs <
15318 probe->dofpr_offidx ||
15319 (probe->dofpr_offidx + probe->dofpr_noffs) *
15320 off_sec->dofs_entsize > off_sec->dofs_size) {
15321 dtrace_dof_error(dof, "invalid probe offset");
15322 return (-1);
15323 }
15324
15325 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1) {
15326 /*
15327 * If there's no is-enabled offset section, make sure
15328 * there aren't any is-enabled offsets. Otherwise
15329 * perform the same checks as for probe offsets
15330 * (immediately above).
15331 */
15332 if (enoff_sec == NULL) {
15333 if (probe->dofpr_enoffidx != 0 ||
15334 probe->dofpr_nenoffs != 0) {
15335 dtrace_dof_error(dof, "is-enabled "
15336 "offsets with null section");
15337 return (-1);
15338 }
15339 } else if (probe->dofpr_enoffidx +
15340 probe->dofpr_nenoffs < probe->dofpr_enoffidx ||
15341 (probe->dofpr_enoffidx + probe->dofpr_nenoffs) *
15342 enoff_sec->dofs_entsize > enoff_sec->dofs_size) {
15343 dtrace_dof_error(dof, "invalid is-enabled "
15344 "offset");
15345 return (-1);
15346 }
15347
15348 if (probe->dofpr_noffs + probe->dofpr_nenoffs == 0) {
15349 dtrace_dof_error(dof, "zero probe and "
15350 "is-enabled offsets");
15351 return (-1);
15352 }
15353 } else if (probe->dofpr_noffs == 0) {
15354 dtrace_dof_error(dof, "zero probe offsets");
15355 return (-1);
15356 }
15357
15358 if (probe->dofpr_argidx + probe->dofpr_xargc <
15359 probe->dofpr_argidx ||
15360 (probe->dofpr_argidx + probe->dofpr_xargc) *
15361 arg_sec->dofs_entsize > arg_sec->dofs_size) {
15362 dtrace_dof_error(dof, "invalid args");
15363 return (-1);
15364 }
15365
15366 typeidx = probe->dofpr_nargv;
15367 typestr = strtab + probe->dofpr_nargv;
15368 for (k = 0; k < probe->dofpr_nargc; k++) {
15369 if (typeidx >= str_sec->dofs_size) {
15370 dtrace_dof_error(dof, "bad "
15371 "native argument type");
15372 return (-1);
15373 }
15374
15375 typesz = strlen(typestr) + 1;
15376 if (typesz > DTRACE_ARGTYPELEN) {
15377 dtrace_dof_error(dof, "native "
15378 "argument type too long");
15379 return (-1);
15380 }
15381 typeidx += typesz;
15382 typestr += typesz;
15383 }
15384
15385 typeidx = probe->dofpr_xargv;
15386 typestr = strtab + probe->dofpr_xargv;
15387 for (k = 0; k < probe->dofpr_xargc; k++) {
15388 if (arg[probe->dofpr_argidx + k] > probe->dofpr_nargc) {
15389 dtrace_dof_error(dof, "bad "
15390 "native argument index");
15391 return (-1);
15392 }
15393
15394 if (typeidx >= str_sec->dofs_size) {
15395 dtrace_dof_error(dof, "bad "
15396 "translated argument type");
15397 return (-1);
15398 }
15399
15400 typesz = strlen(typestr) + 1;
15401 if (typesz > DTRACE_ARGTYPELEN) {
15402 dtrace_dof_error(dof, "translated argument "
15403 "type too long");
15404 return (-1);
15405 }
15406
15407 typeidx += typesz;
15408 typestr += typesz;
15409 }
15410 }
15411
15412 return (0);
15413 }
15414
15415 static int
15416 dtrace_helper_slurp(dof_hdr_t *dof, dof_helper_t *dhp)
15417 {
15418 dtrace_helpers_t *help;
15419 dtrace_vstate_t *vstate;
15420 dtrace_enabling_t *enab = NULL;
15421 int i, gen, rv, nhelpers = 0, nprovs = 0, destroy = 1;
15422 uintptr_t daddr = (uintptr_t)dof;
15423
15424 ASSERT(MUTEX_HELD(&dtrace_lock));
15425
15426 if ((help = curproc->p_dtrace_helpers) == NULL)
15427 help = dtrace_helpers_create(curproc);
15428
15429 vstate = &help->dthps_vstate;
15430
15431 if ((rv = dtrace_dof_slurp(dof, vstate, NULL, &enab,
15432 dhp != NULL ? dhp->dofhp_addr : 0, B_FALSE)) != 0) {
15433 dtrace_dof_destroy(dof);
15434 return (rv);
15435 }
15436
15437 /*
15438 * Look for helper providers and validate their descriptions.
15439 */
15440 if (dhp != NULL) {
15441 for (i = 0; i < dof->dofh_secnum; i++) {
15442 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
15443 dof->dofh_secoff + i * dof->dofh_secsize);
15444
15445 if (sec->dofs_type != DOF_SECT_PROVIDER)
15446 continue;
15447
15448 if (dtrace_helper_provider_validate(dof, sec) != 0) {
15449 dtrace_enabling_destroy(enab);
15450 dtrace_dof_destroy(dof);
15451 return (-1);
15452 }
15453
15454 nprovs++;
15455 }
15456 }
15457
15458 /*
15459 * Now we need to walk through the ECB descriptions in the enabling.
15460 */
15461 for (i = 0; i < enab->dten_ndesc; i++) {
15462 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
15463 dtrace_probedesc_t *desc = &ep->dted_probe;
15464
15465 if (strcmp(desc->dtpd_provider, "dtrace") != 0)
15466 continue;
15467
15468 if (strcmp(desc->dtpd_mod, "helper") != 0)
15469 continue;
15470
15471 if (strcmp(desc->dtpd_func, "ustack") != 0)
15472 continue;
15473
15474 if ((rv = dtrace_helper_action_add(DTRACE_HELPER_ACTION_USTACK,
15475 ep)) != 0) {
15476 /*
15477 * Adding this helper action failed -- we are now going
15478 * to rip out the entire generation and return failure.
15479 */
15480 (void) dtrace_helper_destroygen(help->dthps_generation);
15481 dtrace_enabling_destroy(enab);
15482 dtrace_dof_destroy(dof);
15483 return (-1);
15484 }
15485
15486 nhelpers++;
15487 }
15488
15489 if (nhelpers < enab->dten_ndesc)
15490 dtrace_dof_error(dof, "unmatched helpers");
15491
15492 gen = help->dthps_generation++;
15493 dtrace_enabling_destroy(enab);
15494
15495 if (dhp != NULL && nprovs > 0) {
15496 /*
15497 * Now that this is in-kernel, we change the sense of the
15498 * members: dofhp_dof denotes the in-kernel copy of the DOF
15499 * and dofhp_addr denotes the address at user-level.
15500 */
15501 dhp->dofhp_addr = dhp->dofhp_dof;
15502 dhp->dofhp_dof = (uint64_t)(uintptr_t)dof;
15503
15504 if (dtrace_helper_provider_add(dhp, gen) == 0) {
15505 mutex_exit(&dtrace_lock);
15506 dtrace_helper_provider_register(curproc, help, dhp);
15507 mutex_enter(&dtrace_lock);
15508
15509 destroy = 0;
15510 }
15511 }
15512
15513 if (destroy)
15514 dtrace_dof_destroy(dof);
15515
15516 return (gen);
15517 }
15518
15519 static dtrace_helpers_t *
15520 dtrace_helpers_create(proc_t *p)
15521 {
15522 dtrace_helpers_t *help;
15523
15524 ASSERT(MUTEX_HELD(&dtrace_lock));
15525 ASSERT(p->p_dtrace_helpers == NULL);
15526
15527 help = kmem_zalloc(sizeof (dtrace_helpers_t), KM_SLEEP);
15528 help->dthps_actions = kmem_zalloc(sizeof (dtrace_helper_action_t *) *
15529 DTRACE_NHELPER_ACTIONS, KM_SLEEP);
15530
15531 p->p_dtrace_helpers = help;
15532 dtrace_helpers++;
15533
15534 return (help);
15535 }
15536
15537 static void
15538 dtrace_helpers_destroy(proc_t *p)
15539 {
15540 dtrace_helpers_t *help;
15541 dtrace_vstate_t *vstate;
15542 int i;
15543
15544 mutex_enter(&dtrace_lock);
15545
15546 ASSERT(p->p_dtrace_helpers != NULL);
15547 ASSERT(dtrace_helpers > 0);
15548
15549 help = p->p_dtrace_helpers;
15550 vstate = &help->dthps_vstate;
15551
15552 /*
15553 * We're now going to lose the help from this process.
15554 */
15555 p->p_dtrace_helpers = NULL;
15556 if (p == curproc) {
15557 dtrace_sync();
15558 } else {
15559 /*
15560 * It is sometimes necessary to clean up dtrace helpers from a
15561 * an incomplete child process as part of a failed fork
15562 * operation. In such situations, a dtrace_sync() call should
15563 * be unnecessary as the process should be devoid of threads,
15564 * much less any in probe context.
15565 */
15566 VERIFY(p->p_stat == SIDL);
15567 }
15568
15569 /*
15570 * Destroy the helper actions.
15571 */
15572 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
15573 dtrace_helper_action_t *h, *next;
15574
15575 for (h = help->dthps_actions[i]; h != NULL; h = next) {
15576 next = h->dtha_next;
15577 dtrace_helper_action_destroy(h, vstate);
15578 h = next;
15579 }
15580 }
15581
15582 mutex_exit(&dtrace_lock);
15583
15584 /*
15585 * Destroy the helper providers.
15586 */
15587 if (help->dthps_maxprovs > 0) {
15588 mutex_enter(&dtrace_meta_lock);
15589 if (dtrace_meta_pid != NULL) {
15590 ASSERT(dtrace_deferred_pid == NULL);
15591
15592 for (i = 0; i < help->dthps_nprovs; i++) {
15593 dtrace_helper_provider_remove(
15594 &help->dthps_provs[i]->dthp_prov, p->p_pid);
15595 }
15596 } else {
15597 mutex_enter(&dtrace_lock);
15598 ASSERT(help->dthps_deferred == 0 ||
15599 help->dthps_next != NULL ||
15600 help->dthps_prev != NULL ||
15601 help == dtrace_deferred_pid);
15602
15603 /*
15604 * Remove the helper from the deferred list.
15605 */
15606 if (help->dthps_next != NULL)
15607 help->dthps_next->dthps_prev = help->dthps_prev;
15608 if (help->dthps_prev != NULL)
15609 help->dthps_prev->dthps_next = help->dthps_next;
15610 if (dtrace_deferred_pid == help) {
15611 dtrace_deferred_pid = help->dthps_next;
15612 ASSERT(help->dthps_prev == NULL);
15613 }
15614
15615 mutex_exit(&dtrace_lock);
15616 }
15617
15618 mutex_exit(&dtrace_meta_lock);
15619
15620 for (i = 0; i < help->dthps_nprovs; i++) {
15621 dtrace_helper_provider_destroy(help->dthps_provs[i]);
15622 }
15623
15624 kmem_free(help->dthps_provs, help->dthps_maxprovs *
15625 sizeof (dtrace_helper_provider_t *));
15626 }
15627
15628 mutex_enter(&dtrace_lock);
15629
15630 dtrace_vstate_fini(&help->dthps_vstate);
15631 kmem_free(help->dthps_actions,
15632 sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS);
15633 kmem_free(help, sizeof (dtrace_helpers_t));
15634
15635 --dtrace_helpers;
15636 mutex_exit(&dtrace_lock);
15637 }
15638
15639 static void
15640 dtrace_helpers_duplicate(proc_t *from, proc_t *to)
15641 {
15642 dtrace_helpers_t *help, *newhelp;
15643 dtrace_helper_action_t *helper, *new, *last;
15644 dtrace_difo_t *dp;
15645 dtrace_vstate_t *vstate;
15646 int i, j, sz, hasprovs = 0;
15647
15648 mutex_enter(&dtrace_lock);
15649 ASSERT(from->p_dtrace_helpers != NULL);
15650 ASSERT(dtrace_helpers > 0);
15651
15652 help = from->p_dtrace_helpers;
15653 newhelp = dtrace_helpers_create(to);
15654 ASSERT(to->p_dtrace_helpers != NULL);
15655
15656 newhelp->dthps_generation = help->dthps_generation;
15657 vstate = &newhelp->dthps_vstate;
15658
15659 /*
15660 * Duplicate the helper actions.
15661 */
15662 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
15663 if ((helper = help->dthps_actions[i]) == NULL)
15664 continue;
15665
15666 for (last = NULL; helper != NULL; helper = helper->dtha_next) {
15667 new = kmem_zalloc(sizeof (dtrace_helper_action_t),
15668 KM_SLEEP);
15669 new->dtha_generation = helper->dtha_generation;
15670
15671 if ((dp = helper->dtha_predicate) != NULL) {
15672 dp = dtrace_difo_duplicate(dp, vstate);
15673 new->dtha_predicate = dp;
15674 }
15675
15676 new->dtha_nactions = helper->dtha_nactions;
15677 sz = sizeof (dtrace_difo_t *) * new->dtha_nactions;
15678 new->dtha_actions = kmem_alloc(sz, KM_SLEEP);
15679
15680 for (j = 0; j < new->dtha_nactions; j++) {
15681 dtrace_difo_t *dp = helper->dtha_actions[j];
15682
15683 ASSERT(dp != NULL);
15684 dp = dtrace_difo_duplicate(dp, vstate);
15685 new->dtha_actions[j] = dp;
15686 }
15687
15688 if (last != NULL) {
15689 last->dtha_next = new;
15690 } else {
15691 newhelp->dthps_actions[i] = new;
15692 }
15693
15694 last = new;
15695 }
15696 }
15697
15698 /*
15699 * Duplicate the helper providers and register them with the
15700 * DTrace framework.
15701 */
15702 if (help->dthps_nprovs > 0) {
15703 newhelp->dthps_nprovs = help->dthps_nprovs;
15704 newhelp->dthps_maxprovs = help->dthps_nprovs;
15705 newhelp->dthps_provs = kmem_alloc(newhelp->dthps_nprovs *
15706 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
15707 for (i = 0; i < newhelp->dthps_nprovs; i++) {
15708 newhelp->dthps_provs[i] = help->dthps_provs[i];
15709 newhelp->dthps_provs[i]->dthp_ref++;
15710 }
15711
15712 hasprovs = 1;
15713 }
15714
15715 mutex_exit(&dtrace_lock);
15716
15717 if (hasprovs)
15718 dtrace_helper_provider_register(to, newhelp, NULL);
15719 }
15720
15721 /*
15722 * DTrace Hook Functions
15723 */
15724 static void
15725 dtrace_module_loaded(struct modctl *ctl)
15726 {
15727 dtrace_provider_t *prv;
15728
15729 mutex_enter(&dtrace_provider_lock);
15730 mutex_enter(&mod_lock);
15731
15732 ASSERT(ctl->mod_busy);
15733
15734 /*
15735 * We're going to call each providers per-module provide operation
15736 * specifying only this module.
15737 */
15738 for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next)
15739 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
15740
15741 mutex_exit(&mod_lock);
15742 mutex_exit(&dtrace_provider_lock);
15743
15744 /*
15745 * If we have any retained enablings, we need to match against them.
15746 * Enabling probes requires that cpu_lock be held, and we cannot hold
15747 * cpu_lock here -- it is legal for cpu_lock to be held when loading a
15748 * module. (In particular, this happens when loading scheduling
15749 * classes.) So if we have any retained enablings, we need to dispatch
15750 * our task queue to do the match for us.
15751 */
15752 mutex_enter(&dtrace_lock);
15753
15754 if (dtrace_retained == NULL) {
15755 mutex_exit(&dtrace_lock);
15756 return;
15757 }
15758
15759 (void) taskq_dispatch(dtrace_taskq,
15760 (task_func_t *)dtrace_enabling_matchall, NULL, TQ_SLEEP);
15761
15762 mutex_exit(&dtrace_lock);
15763
15764 /*
15765 * And now, for a little heuristic sleaze: in general, we want to
15766 * match modules as soon as they load. However, we cannot guarantee
15767 * this, because it would lead us to the lock ordering violation
15768 * outlined above. The common case, of course, is that cpu_lock is
15769 * _not_ held -- so we delay here for a clock tick, hoping that that's
15770 * long enough for the task queue to do its work. If it's not, it's
15771 * not a serious problem -- it just means that the module that we
15772 * just loaded may not be immediately instrumentable.
15773 */
15774 delay(1);
15775 }
15776
15777 static void
15778 dtrace_module_unloaded(struct modctl *ctl)
15779 {
15780 dtrace_probe_t template, *probe, *first, *next;
15781 dtrace_provider_t *prov;
15782
15783 template.dtpr_mod = ctl->mod_modname;
15784
15785 mutex_enter(&dtrace_provider_lock);
15786 mutex_enter(&mod_lock);
15787 mutex_enter(&dtrace_lock);
15788
15789 if (dtrace_bymod == NULL) {
15790 /*
15791 * The DTrace module is loaded (obviously) but not attached;
15792 * we don't have any work to do.
15793 */
15794 mutex_exit(&dtrace_provider_lock);
15795 mutex_exit(&mod_lock);
15796 mutex_exit(&dtrace_lock);
15797 return;
15798 }
15799
15800 for (probe = first = dtrace_hash_lookup(dtrace_bymod, &template);
15801 probe != NULL; probe = probe->dtpr_nextmod) {
15802 if (probe->dtpr_ecb != NULL) {
15803 mutex_exit(&dtrace_provider_lock);
15804 mutex_exit(&mod_lock);
15805 mutex_exit(&dtrace_lock);
15806
15807 /*
15808 * This shouldn't _actually_ be possible -- we're
15809 * unloading a module that has an enabled probe in it.
15810 * (It's normally up to the provider to make sure that
15811 * this can't happen.) However, because dtps_enable()
15812 * doesn't have a failure mode, there can be an
15813 * enable/unload race. Upshot: we don't want to
15814 * assert, but we're not going to disable the
15815 * probe, either.
15816 */
15817 if (dtrace_err_verbose) {
15818 cmn_err(CE_WARN, "unloaded module '%s' had "
15819 "enabled probes", ctl->mod_modname);
15820 }
15821
15822 return;
15823 }
15824 }
15825
15826 probe = first;
15827
15828 for (first = NULL; probe != NULL; probe = next) {
15829 ASSERT(dtrace_probes[probe->dtpr_id - 1] == probe);
15830
15831 dtrace_probes[probe->dtpr_id - 1] = NULL;
15832
15833 next = probe->dtpr_nextmod;
15834 dtrace_hash_remove(dtrace_bymod, probe);
15835 dtrace_hash_remove(dtrace_byfunc, probe);
15836 dtrace_hash_remove(dtrace_byname, probe);
15837
15838 if (first == NULL) {
15839 first = probe;
15840 probe->dtpr_nextmod = NULL;
15841 } else {
15842 probe->dtpr_nextmod = first;
15843 first = probe;
15844 }
15845 }
15846
15847 /*
15848 * We've removed all of the module's probes from the hash chains and
15849 * from the probe array. Now issue a dtrace_sync() to be sure that
15850 * everyone has cleared out from any probe array processing.
15851 */
15852 dtrace_sync();
15853
15854 for (probe = first; probe != NULL; probe = first) {
15855 first = probe->dtpr_nextmod;
15856 prov = probe->dtpr_provider;
15857 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, probe->dtpr_id,
15858 probe->dtpr_arg);
15859 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
15860 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
15861 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
15862 vmem_free(dtrace_arena, (void *)(uintptr_t)probe->dtpr_id, 1);
15863 kmem_free(probe, sizeof (dtrace_probe_t));
15864 }
15865
15866 mutex_exit(&dtrace_lock);
15867 mutex_exit(&mod_lock);
15868 mutex_exit(&dtrace_provider_lock);
15869 }
15870
15871 void
15872 dtrace_suspend(void)
15873 {
15874 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_suspend));
15875 }
15876
15877 void
15878 dtrace_resume(void)
15879 {
15880 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_resume));
15881 }
15882
15883 static int
15884 dtrace_cpu_setup(cpu_setup_t what, processorid_t cpu, void *ptr __unused)
15885 {
15886 ASSERT(MUTEX_HELD(&cpu_lock));
15887 mutex_enter(&dtrace_lock);
15888
15889 switch (what) {
15890 case CPU_CONFIG: {
15891 dtrace_state_t *state;
15892 dtrace_optval_t *opt, rs, c;
15893
15894 /*
15895 * For now, we only allocate a new buffer for anonymous state.
15896 */
15897 if ((state = dtrace_anon.dta_state) == NULL)
15898 break;
15899
15900 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
15901 break;
15902
15903 opt = state->dts_options;
15904 c = opt[DTRACEOPT_CPU];
15905
15906 if (c != DTRACE_CPUALL && c != DTRACEOPT_UNSET && c != cpu)
15907 break;
15908
15909 /*
15910 * Regardless of what the actual policy is, we're going to
15911 * temporarily set our resize policy to be manual. We're
15912 * also going to temporarily set our CPU option to denote
15913 * the newly configured CPU.
15914 */
15915 rs = opt[DTRACEOPT_BUFRESIZE];
15916 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_MANUAL;
15917 opt[DTRACEOPT_CPU] = (dtrace_optval_t)cpu;
15918
15919 (void) dtrace_state_buffers(state);
15920
15921 opt[DTRACEOPT_BUFRESIZE] = rs;
15922 opt[DTRACEOPT_CPU] = c;
15923
15924 break;
15925 }
15926
15927 case CPU_UNCONFIG:
15928 /*
15929 * We don't free the buffer in the CPU_UNCONFIG case. (The
15930 * buffer will be freed when the consumer exits.)
15931 */
15932 break;
15933
15934 default:
15935 break;
15936 }
15937
15938 mutex_exit(&dtrace_lock);
15939 return (0);
15940 }
15941
15942 static void
15943 dtrace_cpu_setup_initial(processorid_t cpu)
15944 {
15945 (void) dtrace_cpu_setup(CPU_CONFIG, cpu, NULL);
15946 }
15947
15948 static void
15949 dtrace_toxrange_add(uintptr_t base, uintptr_t limit)
15950 {
15951 if (dtrace_toxranges >= dtrace_toxranges_max) {
15952 int osize, nsize;
15953 dtrace_toxrange_t *range;
15954
15955 osize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
15956
15957 if (osize == 0) {
15958 ASSERT(dtrace_toxrange == NULL);
15959 ASSERT(dtrace_toxranges_max == 0);
15960 dtrace_toxranges_max = 1;
15961 } else {
15962 dtrace_toxranges_max <<= 1;
15963 }
15964
15965 nsize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
15966 range = kmem_zalloc(nsize, KM_SLEEP);
15967
15968 if (dtrace_toxrange != NULL) {
15969 ASSERT(osize != 0);
15970 bcopy(dtrace_toxrange, range, osize);
15971 kmem_free(dtrace_toxrange, osize);
15972 }
15973
15974 dtrace_toxrange = range;
15975 }
15976
15977 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_base == (uintptr_t)NULL);
15978 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_limit == (uintptr_t)NULL);
15979
15980 dtrace_toxrange[dtrace_toxranges].dtt_base = base;
15981 dtrace_toxrange[dtrace_toxranges].dtt_limit = limit;
15982 dtrace_toxranges++;
15983 }
15984
15985 static void
15986 dtrace_getf_barrier()
15987 {
15988 /*
15989 * When we have unprivileged (that is, non-DTRACE_CRV_KERNEL) enablings
15990 * that contain calls to getf(), this routine will be called on every
15991 * closef() before either the underlying vnode is released or the
15992 * file_t itself is freed. By the time we are here, it is essential
15993 * that the file_t can no longer be accessed from a call to getf()
15994 * in probe context -- that assures that a dtrace_sync() can be used
15995 * to clear out any enablings referring to the old structures.
15996 */
15997 if (curthread->t_procp->p_zone->zone_dtrace_getf != 0 ||
15998 kcred->cr_zone->zone_dtrace_getf != 0)
15999 dtrace_sync();
16000 }
16001
16002 /*
16003 * DTrace Driver Cookbook Functions
16004 */
16005 /*ARGSUSED*/
16006 static int
16007 dtrace_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
16008 {
16009 dtrace_provider_id_t id;
16010 dtrace_state_t *state = NULL;
16011 dtrace_enabling_t *enab;
16012
16013 mutex_enter(&cpu_lock);
16014 mutex_enter(&dtrace_provider_lock);
16015 mutex_enter(&dtrace_lock);
16016
16017 if (ddi_soft_state_init(&dtrace_softstate,
16018 sizeof (dtrace_state_t), 0) != 0) {
16019 cmn_err(CE_NOTE, "/dev/dtrace failed to initialize soft state");
16020 mutex_exit(&cpu_lock);
16021 mutex_exit(&dtrace_provider_lock);
16022 mutex_exit(&dtrace_lock);
16023 return (DDI_FAILURE);
16024 }
16025
16026 if (ddi_create_minor_node(devi, DTRACEMNR_DTRACE, S_IFCHR,
16027 DTRACEMNRN_DTRACE, DDI_PSEUDO, 0) == DDI_FAILURE ||
16028 ddi_create_minor_node(devi, DTRACEMNR_HELPER, S_IFCHR,
16029 DTRACEMNRN_HELPER, DDI_PSEUDO, 0) == DDI_FAILURE) {
16030 cmn_err(CE_NOTE, "/dev/dtrace couldn't create minor nodes");
16031 ddi_remove_minor_node(devi, NULL);
16032 ddi_soft_state_fini(&dtrace_softstate);
16033 mutex_exit(&cpu_lock);
16034 mutex_exit(&dtrace_provider_lock);
16035 mutex_exit(&dtrace_lock);
16036 return (DDI_FAILURE);
16037 }
16038
16039 ddi_report_dev(devi);
16040 dtrace_devi = devi;
16041
16042 dtrace_modload = dtrace_module_loaded;
16043 dtrace_modunload = dtrace_module_unloaded;
16044 dtrace_cpu_init = dtrace_cpu_setup_initial;
16045 dtrace_helpers_cleanup = dtrace_helpers_destroy;
16046 dtrace_helpers_fork = dtrace_helpers_duplicate;
16047 dtrace_cpustart_init = dtrace_suspend;
16048 dtrace_cpustart_fini = dtrace_resume;
16049 dtrace_debugger_init = dtrace_suspend;
16050 dtrace_debugger_fini = dtrace_resume;
16051
16052 register_cpu_setup_func(dtrace_cpu_setup, NULL);
16053
16054 ASSERT(MUTEX_HELD(&cpu_lock));
16055
16056 dtrace_arena = vmem_create("dtrace", (void *)1, UINT32_MAX, 1,
16057 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
16058 dtrace_minor = vmem_create("dtrace_minor", (void *)DTRACEMNRN_CLONE,
16059 UINT32_MAX - DTRACEMNRN_CLONE, 1, NULL, NULL, NULL, 0,
16060 VM_SLEEP | VMC_IDENTIFIER);
16061 dtrace_taskq = taskq_create("dtrace_taskq", 1, maxclsyspri,
16062 1, INT_MAX, 0);
16063
16064 dtrace_state_cache = kmem_cache_create("dtrace_state_cache",
16065 sizeof (dtrace_dstate_percpu_t) * NCPU, DTRACE_STATE_ALIGN,
16066 NULL, NULL, NULL, NULL, NULL, 0);
16067
16068 ASSERT(MUTEX_HELD(&cpu_lock));
16069 dtrace_bymod = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_mod),
16070 offsetof(dtrace_probe_t, dtpr_nextmod),
16071 offsetof(dtrace_probe_t, dtpr_prevmod));
16072
16073 dtrace_byfunc = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_func),
16074 offsetof(dtrace_probe_t, dtpr_nextfunc),
16075 offsetof(dtrace_probe_t, dtpr_prevfunc));
16076
16077 dtrace_byname = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_name),
16078 offsetof(dtrace_probe_t, dtpr_nextname),
16079 offsetof(dtrace_probe_t, dtpr_prevname));
16080
16081 if (dtrace_retain_max < 1) {
16082 cmn_err(CE_WARN, "illegal value (%lu) for dtrace_retain_max; "
16083 "setting to 1", dtrace_retain_max);
16084 dtrace_retain_max = 1;
16085 }
16086
16087 /*
16088 * Now discover our toxic ranges.
16089 */
16090 dtrace_toxic_ranges(dtrace_toxrange_add);
16091
16092 /*
16093 * Before we register ourselves as a provider to our own framework,
16094 * we would like to assert that dtrace_provider is NULL -- but that's
16095 * not true if we were loaded as a dependency of a DTrace provider.
16096 * Once we've registered, we can assert that dtrace_provider is our
16097 * pseudo provider.
16098 */
16099 (void) dtrace_register("dtrace", &dtrace_provider_attr,
16100 DTRACE_PRIV_NONE, 0, &dtrace_provider_ops, NULL, &id);
16101
16102 ASSERT(dtrace_provider != NULL);
16103 ASSERT((dtrace_provider_id_t)dtrace_provider == id);
16104
16105 dtrace_probeid_begin = dtrace_probe_create((dtrace_provider_id_t)
16106 dtrace_provider, NULL, NULL, "BEGIN", 0, NULL);
16107 dtrace_probeid_end = dtrace_probe_create((dtrace_provider_id_t)
16108 dtrace_provider, NULL, NULL, "END", 0, NULL);
16109 dtrace_probeid_error = dtrace_probe_create((dtrace_provider_id_t)
16110 dtrace_provider, NULL, NULL, "ERROR", 1, NULL);
16111
16112 dtrace_anon_property();
16113 mutex_exit(&cpu_lock);
16114
16115 /*
16116 * If there are already providers, we must ask them to provide their
16117 * probes, and then match any anonymous enabling against them. Note
16118 * that there should be no other retained enablings at this time:
16119 * the only retained enablings at this time should be the anonymous
16120 * enabling.
16121 */
16122 if (dtrace_anon.dta_enabling != NULL) {
16123 ASSERT(dtrace_retained == dtrace_anon.dta_enabling);
16124
16125 dtrace_enabling_provide(NULL);
16126 state = dtrace_anon.dta_state;
16127
16128 /*
16129 * We couldn't hold cpu_lock across the above call to
16130 * dtrace_enabling_provide(), but we must hold it to actually
16131 * enable the probes. We have to drop all of our locks, pick
16132 * up cpu_lock, and regain our locks before matching the
16133 * retained anonymous enabling.
16134 */
16135 mutex_exit(&dtrace_lock);
16136 mutex_exit(&dtrace_provider_lock);
16137
16138 mutex_enter(&cpu_lock);
16139 mutex_enter(&dtrace_provider_lock);
16140 mutex_enter(&dtrace_lock);
16141
16142 if ((enab = dtrace_anon.dta_enabling) != NULL)
16143 (void) dtrace_enabling_match(enab, NULL);
16144
16145 mutex_exit(&cpu_lock);
16146 }
16147
16148 mutex_exit(&dtrace_lock);
16149 mutex_exit(&dtrace_provider_lock);
16150
16151 if (state != NULL) {
16152 /*
16153 * If we created any anonymous state, set it going now.
16154 */
16155 (void) dtrace_state_go(state, &dtrace_anon.dta_beganon);
16156 }
16157
16158 return (DDI_SUCCESS);
16159 }
16160
16161 /*ARGSUSED*/
16162 static int
16163 dtrace_open(dev_t *devp, int flag, int otyp, cred_t *cred_p)
16164 {
16165 dtrace_state_t *state;
16166 uint32_t priv;
16167 uid_t uid;
16168 zoneid_t zoneid;
16169
16170 if (getminor(*devp) == DTRACEMNRN_HELPER)
16171 return (0);
16172
16173 /*
16174 * If this wasn't an open with the "helper" minor, then it must be
16175 * the "dtrace" minor.
16176 */
16177 if (getminor(*devp) != DTRACEMNRN_DTRACE)
16178 return (ENXIO);
16179
16180 /*
16181 * If no DTRACE_PRIV_* bits are set in the credential, then the
16182 * caller lacks sufficient permission to do anything with DTrace.
16183 */
16184 dtrace_cred2priv(cred_p, &priv, &uid, &zoneid);
16185 if (priv == DTRACE_PRIV_NONE)
16186 return (EACCES);
16187
16188 /*
16189 * Ask all providers to provide all their probes.
16190 */
16191 mutex_enter(&dtrace_provider_lock);
16192 dtrace_probe_provide(NULL, NULL);
16193 mutex_exit(&dtrace_provider_lock);
16194
16195 mutex_enter(&cpu_lock);
16196 mutex_enter(&dtrace_lock);
16197 dtrace_opens++;
16198 dtrace_membar_producer();
16199
16200 /*
16201 * If the kernel debugger is active (that is, if the kernel debugger
16202 * modified text in some way), we won't allow the open.
16203 */
16204 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
16205 dtrace_opens--;
16206 mutex_exit(&cpu_lock);
16207 mutex_exit(&dtrace_lock);
16208 return (EBUSY);
16209 }
16210
16211 if (dtrace_helptrace_enable && dtrace_helptrace_buffer == NULL) {
16212 /*
16213 * If DTrace helper tracing is enabled, we need to allocate the
16214 * trace buffer and initialize the values.
16215 */
16216 dtrace_helptrace_buffer =
16217 kmem_zalloc(dtrace_helptrace_bufsize, KM_SLEEP);
16218 dtrace_helptrace_next = 0;
16219 dtrace_helptrace_wrapped = 0;
16220 dtrace_helptrace_enable = 0;
16221 }
16222
16223 state = dtrace_state_create(devp, cred_p);
16224 mutex_exit(&cpu_lock);
16225
16226 if (state == NULL) {
16227 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
16228 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
16229 mutex_exit(&dtrace_lock);
16230 return (EAGAIN);
16231 }
16232
16233 mutex_exit(&dtrace_lock);
16234
16235 return (0);
16236 }
16237
16238 /*ARGSUSED*/
16239 static int
16240 dtrace_close(dev_t dev, int flag, int otyp, cred_t *cred_p)
16241 {
16242 minor_t minor = getminor(dev);
16243 dtrace_state_t *state;
16244 dtrace_helptrace_t *buf = NULL;
16245
16246 if (minor == DTRACEMNRN_HELPER)
16247 return (0);
16248
16249 state = ddi_get_soft_state(dtrace_softstate, minor);
16250
16251 mutex_enter(&cpu_lock);
16252 mutex_enter(&dtrace_lock);
16253
16254 if (state->dts_anon) {
16255 /*
16256 * There is anonymous state. Destroy that first.
16257 */
16258 ASSERT(dtrace_anon.dta_state == NULL);
16259 dtrace_state_destroy(state->dts_anon);
16260 }
16261
16262 if (dtrace_helptrace_disable) {
16263 /*
16264 * If we have been told to disable helper tracing, set the
16265 * buffer to NULL before calling into dtrace_state_destroy();
16266 * we take advantage of its dtrace_sync() to know that no
16267 * CPU is in probe context with enabled helper tracing
16268 * after it returns.
16269 */
16270 buf = dtrace_helptrace_buffer;
16271 dtrace_helptrace_buffer = NULL;
16272 }
16273
16274 dtrace_state_destroy(state);
16275 ASSERT(dtrace_opens > 0);
16276
16277 /*
16278 * Only relinquish control of the kernel debugger interface when there
16279 * are no consumers and no anonymous enablings.
16280 */
16281 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
16282 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
16283
16284 if (buf != NULL) {
16285 kmem_free(buf, dtrace_helptrace_bufsize);
16286 dtrace_helptrace_disable = 0;
16287 }
16288
16289 mutex_exit(&dtrace_lock);
16290 mutex_exit(&cpu_lock);
16291
16292 return (0);
16293 }
16294
16295 /*ARGSUSED*/
16296 static int
16297 dtrace_ioctl_helper(int cmd, intptr_t arg, int *rv)
16298 {
16299 int rval;
16300 dof_helper_t help, *dhp = NULL;
16301
16302 switch (cmd) {
16303 case DTRACEHIOC_ADDDOF:
16304 if (copyin((void *)arg, &help, sizeof (help)) != 0) {
16305 dtrace_dof_error(NULL, "failed to copyin DOF helper");
16306 return (EFAULT);
16307 }
16308
16309 dhp = &help;
16310 arg = (intptr_t)help.dofhp_dof;
16311 /*FALLTHROUGH*/
16312
16313 case DTRACEHIOC_ADD: {
16314 dof_hdr_t *dof = dtrace_dof_copyin(arg, &rval);
16315
16316 if (dof == NULL)
16317 return (rval);
16318
16319 mutex_enter(&dtrace_lock);
16320
16321 /*
16322 * dtrace_helper_slurp() takes responsibility for the dof --
16323 * it may free it now or it may save it and free it later.
16324 */
16325 if ((rval = dtrace_helper_slurp(dof, dhp)) != -1) {
16326 *rv = rval;
16327 rval = 0;
16328 } else {
16329 rval = EINVAL;
16330 }
16331
16332 mutex_exit(&dtrace_lock);
16333 return (rval);
16334 }
16335
16336 case DTRACEHIOC_REMOVE: {
16337 mutex_enter(&dtrace_lock);
16338 rval = dtrace_helper_destroygen(arg);
16339 mutex_exit(&dtrace_lock);
16340
16341 return (rval);
16342 }
16343
16344 default:
16345 break;
16346 }
16347
16348 return (ENOTTY);
16349 }
16350
16351 /*ARGSUSED*/
16352 static int
16353 dtrace_ioctl(dev_t dev, int cmd, intptr_t arg, int md, cred_t *cr, int *rv)
16354 {
16355 minor_t minor = getminor(dev);
16356 dtrace_state_t *state;
16357 int rval;
16358
16359 if (minor == DTRACEMNRN_HELPER)
16360 return (dtrace_ioctl_helper(cmd, arg, rv));
16361
16362 state = ddi_get_soft_state(dtrace_softstate, minor);
16363
16364 if (state->dts_anon) {
16365 ASSERT(dtrace_anon.dta_state == NULL);
16366 state = state->dts_anon;
16367 }
16368
16369 switch (cmd) {
16370 case DTRACEIOC_PROVIDER: {
16371 dtrace_providerdesc_t pvd;
16372 dtrace_provider_t *pvp;
16373
16374 if (copyin((void *)arg, &pvd, sizeof (pvd)) != 0)
16375 return (EFAULT);
16376
16377 pvd.dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0';
16378 mutex_enter(&dtrace_provider_lock);
16379
16380 for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) {
16381 if (strcmp(pvp->dtpv_name, pvd.dtvd_name) == 0)
16382 break;
16383 }
16384
16385 mutex_exit(&dtrace_provider_lock);
16386
16387 if (pvp == NULL)
16388 return (ESRCH);
16389
16390 bcopy(&pvp->dtpv_priv, &pvd.dtvd_priv, sizeof (dtrace_ppriv_t));
16391 bcopy(&pvp->dtpv_attr, &pvd.dtvd_attr, sizeof (dtrace_pattr_t));
16392 if (copyout(&pvd, (void *)arg, sizeof (pvd)) != 0)
16393 return (EFAULT);
16394
16395 return (0);
16396 }
16397
16398 case DTRACEIOC_EPROBE: {
16399 dtrace_eprobedesc_t epdesc;
16400 dtrace_ecb_t *ecb;
16401 dtrace_action_t *act;
16402 void *buf;
16403 size_t size;
16404 uintptr_t dest;
16405 int nrecs;
16406
16407 if (copyin((void *)arg, &epdesc, sizeof (epdesc)) != 0)
16408 return (EFAULT);
16409
16410 mutex_enter(&dtrace_lock);
16411
16412 if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) {
16413 mutex_exit(&dtrace_lock);
16414 return (EINVAL);
16415 }
16416
16417 if (ecb->dte_probe == NULL) {
16418 mutex_exit(&dtrace_lock);
16419 return (EINVAL);
16420 }
16421
16422 epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id;
16423 epdesc.dtepd_uarg = ecb->dte_uarg;
16424 epdesc.dtepd_size = ecb->dte_size;
16425
16426 nrecs = epdesc.dtepd_nrecs;
16427 epdesc.dtepd_nrecs = 0;
16428 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
16429 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
16430 continue;
16431
16432 epdesc.dtepd_nrecs++;
16433 }
16434
16435 /*
16436 * Now that we have the size, we need to allocate a temporary
16437 * buffer in which to store the complete description. We need
16438 * the temporary buffer to be able to drop dtrace_lock()
16439 * across the copyout(), below.
16440 */
16441 size = sizeof (dtrace_eprobedesc_t) +
16442 (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t));
16443
16444 buf = kmem_alloc(size, KM_SLEEP);
16445 dest = (uintptr_t)buf;
16446
16447 bcopy(&epdesc, (void *)dest, sizeof (epdesc));
16448 dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]);
16449
16450 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
16451 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
16452 continue;
16453
16454 if (nrecs-- == 0)
16455 break;
16456
16457 bcopy(&act->dta_rec, (void *)dest,
16458 sizeof (dtrace_recdesc_t));
16459 dest += sizeof (dtrace_recdesc_t);
16460 }
16461
16462 mutex_exit(&dtrace_lock);
16463
16464 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
16465 kmem_free(buf, size);
16466 return (EFAULT);
16467 }
16468
16469 kmem_free(buf, size);
16470 return (0);
16471 }
16472
16473 case DTRACEIOC_AGGDESC: {
16474 dtrace_aggdesc_t aggdesc;
16475 dtrace_action_t *act;
16476 dtrace_aggregation_t *agg;
16477 int nrecs;
16478 uint32_t offs;
16479 dtrace_recdesc_t *lrec;
16480 void *buf;
16481 size_t size;
16482 uintptr_t dest;
16483
16484 if (copyin((void *)arg, &aggdesc, sizeof (aggdesc)) != 0)
16485 return (EFAULT);
16486
16487 mutex_enter(&dtrace_lock);
16488
16489 if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) {
16490 mutex_exit(&dtrace_lock);
16491 return (EINVAL);
16492 }
16493
16494 aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid;
16495
16496 nrecs = aggdesc.dtagd_nrecs;
16497 aggdesc.dtagd_nrecs = 0;
16498
16499 offs = agg->dtag_base;
16500 lrec = &agg->dtag_action.dta_rec;
16501 aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs;
16502
16503 for (act = agg->dtag_first; ; act = act->dta_next) {
16504 ASSERT(act->dta_intuple ||
16505 DTRACEACT_ISAGG(act->dta_kind));
16506
16507 /*
16508 * If this action has a record size of zero, it
16509 * denotes an argument to the aggregating action.
16510 * Because the presence of this record doesn't (or
16511 * shouldn't) affect the way the data is interpreted,
16512 * we don't copy it out to save user-level the
16513 * confusion of dealing with a zero-length record.
16514 */
16515 if (act->dta_rec.dtrd_size == 0) {
16516 ASSERT(agg->dtag_hasarg);
16517 continue;
16518 }
16519
16520 aggdesc.dtagd_nrecs++;
16521
16522 if (act == &agg->dtag_action)
16523 break;
16524 }
16525
16526 /*
16527 * Now that we have the size, we need to allocate a temporary
16528 * buffer in which to store the complete description. We need
16529 * the temporary buffer to be able to drop dtrace_lock()
16530 * across the copyout(), below.
16531 */
16532 size = sizeof (dtrace_aggdesc_t) +
16533 (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t));
16534
16535 buf = kmem_alloc(size, KM_SLEEP);
16536 dest = (uintptr_t)buf;
16537
16538 bcopy(&aggdesc, (void *)dest, sizeof (aggdesc));
16539 dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]);
16540
16541 for (act = agg->dtag_first; ; act = act->dta_next) {
16542 dtrace_recdesc_t rec = act->dta_rec;
16543
16544 /*
16545 * See the comment in the above loop for why we pass
16546 * over zero-length records.
16547 */
16548 if (rec.dtrd_size == 0) {
16549 ASSERT(agg->dtag_hasarg);
16550 continue;
16551 }
16552
16553 if (nrecs-- == 0)
16554 break;
16555
16556 rec.dtrd_offset -= offs;
16557 bcopy(&rec, (void *)dest, sizeof (rec));
16558 dest += sizeof (dtrace_recdesc_t);
16559
16560 if (act == &agg->dtag_action)
16561 break;
16562 }
16563
16564 mutex_exit(&dtrace_lock);
16565
16566 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
16567 kmem_free(buf, size);
16568 return (EFAULT);
16569 }
16570
16571 kmem_free(buf, size);
16572 return (0);
16573 }
16574
16575 case DTRACEIOC_ENABLE: {
16576 dof_hdr_t *dof;
16577 dtrace_enabling_t *enab = NULL;
16578 dtrace_vstate_t *vstate;
16579 int err = 0;
16580
16581 *rv = 0;
16582
16583 /*
16584 * If a NULL argument has been passed, we take this as our
16585 * cue to reevaluate our enablings.
16586 */
16587 if (arg == 0) {
16588 dtrace_enabling_matchall();
16589
16590 return (0);
16591 }
16592
16593 if ((dof = dtrace_dof_copyin(arg, &rval)) == NULL)
16594 return (rval);
16595
16596 mutex_enter(&cpu_lock);
16597 mutex_enter(&dtrace_lock);
16598 vstate = &state->dts_vstate;
16599
16600 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
16601 mutex_exit(&dtrace_lock);
16602 mutex_exit(&cpu_lock);
16603 dtrace_dof_destroy(dof);
16604 return (EBUSY);
16605 }
16606
16607 if (dtrace_dof_slurp(dof, vstate, cr, &enab, 0, B_TRUE) != 0) {
16608 mutex_exit(&dtrace_lock);
16609 mutex_exit(&cpu_lock);
16610 dtrace_dof_destroy(dof);
16611 return (EINVAL);
16612 }
16613
16614 if ((rval = dtrace_dof_options(dof, state)) != 0) {
16615 dtrace_enabling_destroy(enab);
16616 mutex_exit(&dtrace_lock);
16617 mutex_exit(&cpu_lock);
16618 dtrace_dof_destroy(dof);
16619 return (rval);
16620 }
16621
16622 if ((err = dtrace_enabling_match(enab, rv)) == 0) {
16623 err = dtrace_enabling_retain(enab);
16624 } else {
16625 dtrace_enabling_destroy(enab);
16626 }
16627
16628 mutex_exit(&cpu_lock);
16629 mutex_exit(&dtrace_lock);
16630 dtrace_dof_destroy(dof);
16631
16632 return (err);
16633 }
16634
16635 case DTRACEIOC_REPLICATE: {
16636 dtrace_repldesc_t desc;
16637 dtrace_probedesc_t *match = &desc.dtrpd_match;
16638 dtrace_probedesc_t *create = &desc.dtrpd_create;
16639 int err;
16640
16641 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16642 return (EFAULT);
16643
16644 match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
16645 match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
16646 match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
16647 match->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
16648
16649 create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
16650 create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
16651 create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
16652 create->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
16653
16654 mutex_enter(&dtrace_lock);
16655 err = dtrace_enabling_replicate(state, match, create);
16656 mutex_exit(&dtrace_lock);
16657
16658 return (err);
16659 }
16660
16661 case DTRACEIOC_PROBEMATCH:
16662 case DTRACEIOC_PROBES: {
16663 dtrace_probe_t *probe = NULL;
16664 dtrace_probedesc_t desc;
16665 dtrace_probekey_t pkey;
16666 dtrace_id_t i;
16667 int m = 0;
16668 uint32_t priv;
16669 uid_t uid;
16670 zoneid_t zoneid;
16671
16672 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16673 return (EFAULT);
16674
16675 desc.dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
16676 desc.dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
16677 desc.dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
16678 desc.dtpd_name[DTRACE_NAMELEN - 1] = '\0';
16679
16680 /*
16681 * Before we attempt to match this probe, we want to give
16682 * all providers the opportunity to provide it.
16683 */
16684 if (desc.dtpd_id == DTRACE_IDNONE) {
16685 mutex_enter(&dtrace_provider_lock);
16686 dtrace_probe_provide(&desc, NULL);
16687 mutex_exit(&dtrace_provider_lock);
16688 desc.dtpd_id++;
16689 }
16690
16691 if (cmd == DTRACEIOC_PROBEMATCH) {
16692 dtrace_probekey(&desc, &pkey);
16693 pkey.dtpk_id = DTRACE_IDNONE;
16694 }
16695
16696 dtrace_cred2priv(cr, &priv, &uid, &zoneid);
16697
16698 mutex_enter(&dtrace_lock);
16699
16700 if (cmd == DTRACEIOC_PROBEMATCH) {
16701 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
16702 if ((probe = dtrace_probes[i - 1]) != NULL &&
16703 (m = dtrace_match_probe(probe, &pkey,
16704 priv, uid, zoneid)) != 0)
16705 break;
16706 }
16707
16708 if (m < 0) {
16709 mutex_exit(&dtrace_lock);
16710 return (EINVAL);
16711 }
16712
16713 } else {
16714 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
16715 if ((probe = dtrace_probes[i - 1]) != NULL &&
16716 dtrace_match_priv(probe, priv, uid, zoneid))
16717 break;
16718 }
16719 }
16720
16721 if (probe == NULL) {
16722 mutex_exit(&dtrace_lock);
16723 return (ESRCH);
16724 }
16725
16726 dtrace_probe_description(probe, &desc);
16727 mutex_exit(&dtrace_lock);
16728
16729 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16730 return (EFAULT);
16731
16732 return (0);
16733 }
16734
16735 case DTRACEIOC_PROBEARG: {
16736 dtrace_argdesc_t desc;
16737 dtrace_probe_t *probe;
16738 dtrace_provider_t *prov;
16739
16740 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16741 return (EFAULT);
16742
16743 if (desc.dtargd_id == DTRACE_IDNONE)
16744 return (EINVAL);
16745
16746 if (desc.dtargd_ndx == DTRACE_ARGNONE)
16747 return (EINVAL);
16748
16749 mutex_enter(&dtrace_provider_lock);
16750 mutex_enter(&mod_lock);
16751 mutex_enter(&dtrace_lock);
16752
16753 if (desc.dtargd_id > dtrace_nprobes) {
16754 mutex_exit(&dtrace_lock);
16755 mutex_exit(&mod_lock);
16756 mutex_exit(&dtrace_provider_lock);
16757 return (EINVAL);
16758 }
16759
16760 if ((probe = dtrace_probes[desc.dtargd_id - 1]) == NULL) {
16761 mutex_exit(&dtrace_lock);
16762 mutex_exit(&mod_lock);
16763 mutex_exit(&dtrace_provider_lock);
16764 return (EINVAL);
16765 }
16766
16767 mutex_exit(&dtrace_lock);
16768
16769 prov = probe->dtpr_provider;
16770
16771 if (prov->dtpv_pops.dtps_getargdesc == NULL) {
16772 /*
16773 * There isn't any typed information for this probe.
16774 * Set the argument number to DTRACE_ARGNONE.
16775 */
16776 desc.dtargd_ndx = DTRACE_ARGNONE;
16777 } else {
16778 desc.dtargd_native[0] = '\0';
16779 desc.dtargd_xlate[0] = '\0';
16780 desc.dtargd_mapping = desc.dtargd_ndx;
16781
16782 prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg,
16783 probe->dtpr_id, probe->dtpr_arg, &desc);
16784 }
16785
16786 mutex_exit(&mod_lock);
16787 mutex_exit(&dtrace_provider_lock);
16788
16789 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16790 return (EFAULT);
16791
16792 return (0);
16793 }
16794
16795 case DTRACEIOC_GO: {
16796 processorid_t cpuid;
16797 rval = dtrace_state_go(state, &cpuid);
16798
16799 if (rval != 0)
16800 return (rval);
16801
16802 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
16803 return (EFAULT);
16804
16805 return (0);
16806 }
16807
16808 case DTRACEIOC_STOP: {
16809 processorid_t cpuid;
16810
16811 mutex_enter(&dtrace_lock);
16812 rval = dtrace_state_stop(state, &cpuid);
16813 mutex_exit(&dtrace_lock);
16814
16815 if (rval != 0)
16816 return (rval);
16817
16818 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
16819 return (EFAULT);
16820
16821 return (0);
16822 }
16823
16824 case DTRACEIOC_DOFGET: {
16825 dof_hdr_t hdr, *dof;
16826 uint64_t len;
16827
16828 if (copyin((void *)arg, &hdr, sizeof (hdr)) != 0)
16829 return (EFAULT);
16830
16831 mutex_enter(&dtrace_lock);
16832 dof = dtrace_dof_create(state);
16833 mutex_exit(&dtrace_lock);
16834
16835 len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz);
16836 rval = copyout(dof, (void *)arg, len);
16837 dtrace_dof_destroy(dof);
16838
16839 return (rval == 0 ? 0 : EFAULT);
16840 }
16841
16842 case DTRACEIOC_AGGSNAP:
16843 case DTRACEIOC_BUFSNAP: {
16844 dtrace_bufdesc_t desc;
16845 caddr_t cached;
16846 dtrace_buffer_t *buf;
16847
16848 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16849 return (EFAULT);
16850
16851 if (desc.dtbd_cpu < 0 || desc.dtbd_cpu >= NCPU)
16852 return (EINVAL);
16853
16854 mutex_enter(&dtrace_lock);
16855
16856 if (cmd == DTRACEIOC_BUFSNAP) {
16857 buf = &state->dts_buffer[desc.dtbd_cpu];
16858 } else {
16859 buf = &state->dts_aggbuffer[desc.dtbd_cpu];
16860 }
16861
16862 if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) {
16863 size_t sz = buf->dtb_offset;
16864
16865 if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) {
16866 mutex_exit(&dtrace_lock);
16867 return (EBUSY);
16868 }
16869
16870 /*
16871 * If this buffer has already been consumed, we're
16872 * going to indicate that there's nothing left here
16873 * to consume.
16874 */
16875 if (buf->dtb_flags & DTRACEBUF_CONSUMED) {
16876 mutex_exit(&dtrace_lock);
16877
16878 desc.dtbd_size = 0;
16879 desc.dtbd_drops = 0;
16880 desc.dtbd_errors = 0;
16881 desc.dtbd_oldest = 0;
16882 sz = sizeof (desc);
16883
16884 if (copyout(&desc, (void *)arg, sz) != 0)
16885 return (EFAULT);
16886
16887 return (0);
16888 }
16889
16890 /*
16891 * If this is a ring buffer that has wrapped, we want
16892 * to copy the whole thing out.
16893 */
16894 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
16895 dtrace_buffer_polish(buf);
16896 sz = buf->dtb_size;
16897 }
16898
16899 if (copyout(buf->dtb_tomax, desc.dtbd_data, sz) != 0) {
16900 mutex_exit(&dtrace_lock);
16901 return (EFAULT);
16902 }
16903
16904 desc.dtbd_size = sz;
16905 desc.dtbd_drops = buf->dtb_drops;
16906 desc.dtbd_errors = buf->dtb_errors;
16907 desc.dtbd_oldest = buf->dtb_xamot_offset;
16908 desc.dtbd_timestamp = dtrace_gethrtime();
16909
16910 mutex_exit(&dtrace_lock);
16911
16912 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16913 return (EFAULT);
16914
16915 buf->dtb_flags |= DTRACEBUF_CONSUMED;
16916
16917 return (0);
16918 }
16919
16920 if (buf->dtb_tomax == NULL) {
16921 ASSERT(buf->dtb_xamot == NULL);
16922 mutex_exit(&dtrace_lock);
16923 return (ENOENT);
16924 }
16925
16926 cached = buf->dtb_tomax;
16927 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
16928
16929 dtrace_xcall(desc.dtbd_cpu,
16930 (dtrace_xcall_t)dtrace_buffer_switch, buf);
16931
16932 state->dts_errors += buf->dtb_xamot_errors;
16933
16934 /*
16935 * If the buffers did not actually switch, then the cross call
16936 * did not take place -- presumably because the given CPU is
16937 * not in the ready set. If this is the case, we'll return
16938 * ENOENT.
16939 */
16940 if (buf->dtb_tomax == cached) {
16941 ASSERT(buf->dtb_xamot != cached);
16942 mutex_exit(&dtrace_lock);
16943 return (ENOENT);
16944 }
16945
16946 ASSERT(cached == buf->dtb_xamot);
16947
16948 /*
16949 * We have our snapshot; now copy it out.
16950 */
16951 if (copyout(buf->dtb_xamot, desc.dtbd_data,
16952 buf->dtb_xamot_offset) != 0) {
16953 mutex_exit(&dtrace_lock);
16954 return (EFAULT);
16955 }
16956
16957 desc.dtbd_size = buf->dtb_xamot_offset;
16958 desc.dtbd_drops = buf->dtb_xamot_drops;
16959 desc.dtbd_errors = buf->dtb_xamot_errors;
16960 desc.dtbd_oldest = 0;
16961 desc.dtbd_timestamp = buf->dtb_switched;
16962
16963 mutex_exit(&dtrace_lock);
16964
16965 /*
16966 * Finally, copy out the buffer description.
16967 */
16968 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16969 return (EFAULT);
16970
16971 return (0);
16972 }
16973
16974 case DTRACEIOC_CONF: {
16975 dtrace_conf_t conf;
16976
16977 bzero(&conf, sizeof (conf));
16978 conf.dtc_difversion = DIF_VERSION;
16979 conf.dtc_difintregs = DIF_DIR_NREGS;
16980 conf.dtc_diftupregs = DIF_DTR_NREGS;
16981 conf.dtc_ctfmodel = CTF_MODEL_NATIVE;
16982
16983 if (copyout(&conf, (void *)arg, sizeof (conf)) != 0)
16984 return (EFAULT);
16985
16986 return (0);
16987 }
16988
16989 case DTRACEIOC_STATUS: {
16990 dtrace_status_t stat;
16991 dtrace_dstate_t *dstate;
16992 int i, j;
16993 uint64_t nerrs;
16994
16995 /*
16996 * See the comment in dtrace_state_deadman() for the reason
16997 * for setting dts_laststatus to INT64_MAX before setting
16998 * it to the correct value.
16999 */
17000 state->dts_laststatus = INT64_MAX;
17001 dtrace_membar_producer();
17002 state->dts_laststatus = dtrace_gethrtime();
17003
17004 bzero(&stat, sizeof (stat));
17005
17006 mutex_enter(&dtrace_lock);
17007
17008 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) {
17009 mutex_exit(&dtrace_lock);
17010 return (ENOENT);
17011 }
17012
17013 if (state->dts_activity == DTRACE_ACTIVITY_DRAINING)
17014 stat.dtst_exiting = 1;
17015
17016 nerrs = state->dts_errors;
17017 dstate = &state->dts_vstate.dtvs_dynvars;
17018
17019 for (i = 0; i < NCPU; i++) {
17020 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i];
17021
17022 stat.dtst_dyndrops += dcpu->dtdsc_drops;
17023 stat.dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops;
17024 stat.dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops;
17025
17026 if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL)
17027 stat.dtst_filled++;
17028
17029 nerrs += state->dts_buffer[i].dtb_errors;
17030
17031 for (j = 0; j < state->dts_nspeculations; j++) {
17032 dtrace_speculation_t *spec;
17033 dtrace_buffer_t *buf;
17034
17035 spec = &state->dts_speculations[j];
17036 buf = &spec->dtsp_buffer[i];
17037 stat.dtst_specdrops += buf->dtb_xamot_drops;
17038 }
17039 }
17040
17041 stat.dtst_specdrops_busy = state->dts_speculations_busy;
17042 stat.dtst_specdrops_unavail = state->dts_speculations_unavail;
17043 stat.dtst_stkstroverflows = state->dts_stkstroverflows;
17044 stat.dtst_dblerrors = state->dts_dblerrors;
17045 stat.dtst_killed =
17046 (state->dts_activity == DTRACE_ACTIVITY_KILLED);
17047 stat.dtst_errors = nerrs;
17048
17049 mutex_exit(&dtrace_lock);
17050
17051 if (copyout(&stat, (void *)arg, sizeof (stat)) != 0)
17052 return (EFAULT);
17053
17054 return (0);
17055 }
17056
17057 case DTRACEIOC_FORMAT: {
17058 dtrace_fmtdesc_t fmt;
17059 char *str;
17060 int len;
17061
17062 if (copyin((void *)arg, &fmt, sizeof (fmt)) != 0)
17063 return (EFAULT);
17064
17065 mutex_enter(&dtrace_lock);
17066
17067 if (fmt.dtfd_format == 0 ||
17068 fmt.dtfd_format > state->dts_nformats) {
17069 mutex_exit(&dtrace_lock);
17070 return (EINVAL);
17071 }
17072
17073 /*
17074 * Format strings are allocated contiguously and they are
17075 * never freed; if a format index is less than the number
17076 * of formats, we can assert that the format map is non-NULL
17077 * and that the format for the specified index is non-NULL.
17078 */
17079 ASSERT(state->dts_formats != NULL);
17080 str = state->dts_formats[fmt.dtfd_format - 1];
17081 ASSERT(str != NULL);
17082
17083 len = strlen(str) + 1;
17084
17085 if (len > fmt.dtfd_length) {
17086 fmt.dtfd_length = len;
17087
17088 if (copyout(&fmt, (void *)arg, sizeof (fmt)) != 0) {
17089 mutex_exit(&dtrace_lock);
17090 return (EINVAL);
17091 }
17092 } else {
17093 if (copyout(str, fmt.dtfd_string, len) != 0) {
17094 mutex_exit(&dtrace_lock);
17095 return (EINVAL);
17096 }
17097 }
17098
17099 mutex_exit(&dtrace_lock);
17100 return (0);
17101 }
17102
17103 default:
17104 break;
17105 }
17106
17107 return (ENOTTY);
17108 }
17109
17110 /*ARGSUSED*/
17111 static int
17112 dtrace_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
17113 {
17114 dtrace_state_t *state;
17115
17116 switch (cmd) {
17117 case DDI_DETACH:
17118 break;
17119
17120 case DDI_SUSPEND:
17121 return (DDI_SUCCESS);
17122
17123 default:
17124 return (DDI_FAILURE);
17125 }
17126
17127 mutex_enter(&cpu_lock);
17128 mutex_enter(&dtrace_provider_lock);
17129 mutex_enter(&dtrace_lock);
17130
17131 ASSERT(dtrace_opens == 0);
17132
17133 if (dtrace_helpers > 0) {
17134 mutex_exit(&dtrace_provider_lock);
17135 mutex_exit(&dtrace_lock);
17136 mutex_exit(&cpu_lock);
17137 return (DDI_FAILURE);
17138 }
17139
17140 if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) {
17141 mutex_exit(&dtrace_provider_lock);
17142 mutex_exit(&dtrace_lock);
17143 mutex_exit(&cpu_lock);
17144 return (DDI_FAILURE);
17145 }
17146
17147 dtrace_provider = NULL;
17148
17149 if ((state = dtrace_anon_grab()) != NULL) {
17150 /*
17151 * If there were ECBs on this state, the provider should
17152 * have not been allowed to detach; assert that there is
17153 * none.
17154 */
17155 ASSERT(state->dts_necbs == 0);
17156 dtrace_state_destroy(state);
17157
17158 /*
17159 * If we're being detached with anonymous state, we need to
17160 * indicate to the kernel debugger that DTrace is now inactive.
17161 */
17162 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
17163 }
17164
17165 bzero(&dtrace_anon, sizeof (dtrace_anon_t));
17166 unregister_cpu_setup_func(dtrace_cpu_setup, NULL);
17167 dtrace_cpu_init = NULL;
17168 dtrace_helpers_cleanup = NULL;
17169 dtrace_helpers_fork = NULL;
17170 dtrace_cpustart_init = NULL;
17171 dtrace_cpustart_fini = NULL;
17172 dtrace_debugger_init = NULL;
17173 dtrace_debugger_fini = NULL;
17174 dtrace_modload = NULL;
17175 dtrace_modunload = NULL;
17176
17177 ASSERT(dtrace_getf == 0);
17178 ASSERT(dtrace_closef == NULL);
17179
17180 mutex_exit(&cpu_lock);
17181
17182 kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *));
17183 dtrace_probes = NULL;
17184 dtrace_nprobes = 0;
17185
17186 dtrace_hash_destroy(dtrace_bymod);
17187 dtrace_hash_destroy(dtrace_byfunc);
17188 dtrace_hash_destroy(dtrace_byname);
17189 dtrace_bymod = NULL;
17190 dtrace_byfunc = NULL;
17191 dtrace_byname = NULL;
17192
17193 kmem_cache_destroy(dtrace_state_cache);
17194 vmem_destroy(dtrace_minor);
17195 vmem_destroy(dtrace_arena);
17196
17197 if (dtrace_toxrange != NULL) {
17198 kmem_free(dtrace_toxrange,
17199 dtrace_toxranges_max * sizeof (dtrace_toxrange_t));
17200 dtrace_toxrange = NULL;
17201 dtrace_toxranges = 0;
17202 dtrace_toxranges_max = 0;
17203 }
17204
17205 ddi_remove_minor_node(dtrace_devi, NULL);
17206 dtrace_devi = NULL;
17207
17208 ddi_soft_state_fini(&dtrace_softstate);
17209
17210 ASSERT(dtrace_vtime_references == 0);
17211 ASSERT(dtrace_opens == 0);
17212 ASSERT(dtrace_retained == NULL);
17213
17214 mutex_exit(&dtrace_lock);
17215 mutex_exit(&dtrace_provider_lock);
17216
17217 /*
17218 * We don't destroy the task queue until after we have dropped our
17219 * locks (taskq_destroy() may block on running tasks). To prevent
17220 * attempting to do work after we have effectively detached but before
17221 * the task queue has been destroyed, all tasks dispatched via the
17222 * task queue must check that DTrace is still attached before
17223 * performing any operation.
17224 */
17225 taskq_destroy(dtrace_taskq);
17226 dtrace_taskq = NULL;
17227
17228 return (DDI_SUCCESS);
17229 }
17230
17231 /*ARGSUSED*/
17232 static int
17233 dtrace_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
17234 {
17235 int error;
17236
17237 switch (infocmd) {
17238 case DDI_INFO_DEVT2DEVINFO:
17239 *result = (void *)dtrace_devi;
17240 error = DDI_SUCCESS;
17241 break;
17242 case DDI_INFO_DEVT2INSTANCE:
17243 *result = (void *)0;
17244 error = DDI_SUCCESS;
17245 break;
17246 default:
17247 error = DDI_FAILURE;
17248 }
17249 return (error);
17250 }
17251
17252 static struct cb_ops dtrace_cb_ops = {
17253 dtrace_open, /* open */
17254 dtrace_close, /* close */
17255 nulldev, /* strategy */
17256 nulldev, /* print */
17257 nodev, /* dump */
17258 nodev, /* read */
17259 nodev, /* write */
17260 dtrace_ioctl, /* ioctl */
17261 nodev, /* devmap */
17262 nodev, /* mmap */
17263 nodev, /* segmap */
17264 nochpoll, /* poll */
17265 ddi_prop_op, /* cb_prop_op */
17266 0, /* streamtab */
17267 D_NEW | D_MP /* Driver compatibility flag */
17268 };
17269
17270 static struct dev_ops dtrace_ops = {
17271 DEVO_REV, /* devo_rev */
17272 0, /* refcnt */
17273 dtrace_info, /* get_dev_info */
17274 nulldev, /* identify */
17275 nulldev, /* probe */
17276 dtrace_attach, /* attach */
17277 dtrace_detach, /* detach */
17278 nodev, /* reset */
17279 &dtrace_cb_ops, /* driver operations */
17280 NULL, /* bus operations */
17281 nodev, /* dev power */
17282 ddi_quiesce_not_needed, /* quiesce */
17283 };
17284
17285 static struct modldrv modldrv = {
17286 &mod_driverops, /* module type (this is a pseudo driver) */
17287 "Dynamic Tracing", /* name of module */
17288 &dtrace_ops, /* driver ops */
17289 };
17290
17291 static struct modlinkage modlinkage = {
17292 MODREV_1,
17293 (void *)&modldrv,
17294 NULL
17295 };
17296
17297 int
17298 _init(void)
17299 {
17300 return (mod_install(&modlinkage));
17301 }
17302
17303 int
17304 _info(struct modinfo *modinfop)
17305 {
17306 return (mod_info(&modlinkage, modinfop));
17307 }
17308
17309 int
17310 _fini(void)
17311 {
17312 return (mod_remove(&modlinkage));
17313 }