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4374 dn_free_ranges should use range_tree_t
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com
Reviewed by: Garrett D'Amore <garrett@damore.org>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>
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--- old/usr/src/uts/common/fs/zfs/zio.c
+++ new/usr/src/uts/common/fs/zfs/zio.c
1 1 /*
2 2 * CDDL HEADER START
3 3 *
4 4 * The contents of this file are subject to the terms of the
5 5 * Common Development and Distribution License (the "License").
6 6 * You may not use this file except in compliance with the License.
7 7 *
8 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 9 * or http://www.opensolaris.org/os/licensing.
10 10 * See the License for the specific language governing permissions
11 11 * and limitations under the License.
12 12 *
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13 13 * When distributing Covered Code, include this CDDL HEADER in each
14 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 15 * If applicable, add the following below this CDDL HEADER, with the
16 16 * fields enclosed by brackets "[]" replaced with your own identifying
17 17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 18 *
19 19 * CDDL HEADER END
20 20 */
21 21 /*
22 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 - * Copyright (c) 2013 by Delphix. All rights reserved.
23 + * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
24 24 * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
25 25 * Copyright 2013 Joyent, Inc. All rights reserved.
26 26 */
27 27
28 28 #include <sys/zfs_context.h>
29 29 #include <sys/fm/fs/zfs.h>
30 30 #include <sys/spa.h>
31 31 #include <sys/txg.h>
32 32 #include <sys/spa_impl.h>
33 33 #include <sys/vdev_impl.h>
34 34 #include <sys/zio_impl.h>
35 35 #include <sys/zio_compress.h>
36 36 #include <sys/zio_checksum.h>
37 37 #include <sys/dmu_objset.h>
38 38 #include <sys/arc.h>
39 39 #include <sys/ddt.h>
40 40 #include <sys/zfs_zone.h>
41 41 #include <sys/zfeature.h>
42 42
43 43 /*
44 44 * ==========================================================================
45 45 * I/O type descriptions
46 46 * ==========================================================================
47 47 */
48 48 const char *zio_type_name[ZIO_TYPES] = {
49 49 "zio_null", "zio_read", "zio_write", "zio_free", "zio_claim",
50 50 "zio_ioctl"
51 51 };
52 52
53 53 /*
54 54 * ==========================================================================
55 55 * I/O kmem caches
56 56 * ==========================================================================
57 57 */
58 58 kmem_cache_t *zio_cache;
59 59 kmem_cache_t *zio_link_cache;
60 60 kmem_cache_t *zio_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
61 61 kmem_cache_t *zio_data_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
62 62
63 63 #ifdef _KERNEL
64 64 extern vmem_t *zio_alloc_arena;
65 65 #endif
66 66 extern int zfs_mg_alloc_failures;
67 67
68 68 /*
69 69 * The following actions directly effect the spa's sync-to-convergence logic.
70 70 * The values below define the sync pass when we start performing the action.
71 71 * Care should be taken when changing these values as they directly impact
72 72 * spa_sync() performance. Tuning these values may introduce subtle performance
73 73 * pathologies and should only be done in the context of performance analysis.
74 74 * These tunables will eventually be removed and replaced with #defines once
75 75 * enough analysis has been done to determine optimal values.
76 76 *
77 77 * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that
78 78 * regular blocks are not deferred.
79 79 */
80 80 int zfs_sync_pass_deferred_free = 2; /* defer frees starting in this pass */
81 81 int zfs_sync_pass_dont_compress = 5; /* don't compress starting in this pass */
82 82 int zfs_sync_pass_rewrite = 2; /* rewrite new bps starting in this pass */
83 83
84 84 /*
85 85 * An allocating zio is one that either currently has the DVA allocate
86 86 * stage set or will have it later in its lifetime.
87 87 */
88 88 #define IO_IS_ALLOCATING(zio) ((zio)->io_orig_pipeline & ZIO_STAGE_DVA_ALLOCATE)
89 89
90 90 boolean_t zio_requeue_io_start_cut_in_line = B_TRUE;
91 91
92 92 #ifdef ZFS_DEBUG
93 93 int zio_buf_debug_limit = 16384;
94 94 #else
95 95 int zio_buf_debug_limit = 0;
96 96 #endif
97 97
98 98 void
99 99 zio_init(void)
100 100 {
101 101 size_t c;
102 102 vmem_t *data_alloc_arena = NULL;
103 103
104 104 #ifdef _KERNEL
105 105 data_alloc_arena = zio_alloc_arena;
106 106 #endif
107 107 zio_cache = kmem_cache_create("zio_cache",
108 108 sizeof (zio_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
109 109 zio_link_cache = kmem_cache_create("zio_link_cache",
110 110 sizeof (zio_link_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
111 111
112 112 /*
113 113 * For small buffers, we want a cache for each multiple of
114 114 * SPA_MINBLOCKSIZE. For medium-size buffers, we want a cache
115 115 * for each quarter-power of 2. For large buffers, we want
116 116 * a cache for each multiple of PAGESIZE.
117 117 */
118 118 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) {
119 119 size_t size = (c + 1) << SPA_MINBLOCKSHIFT;
120 120 size_t p2 = size;
121 121 size_t align = 0;
122 122 size_t cflags = (size > zio_buf_debug_limit) ? KMC_NODEBUG : 0;
123 123
124 124 while (p2 & (p2 - 1))
125 125 p2 &= p2 - 1;
126 126
127 127 #ifndef _KERNEL
128 128 /*
129 129 * If we are using watchpoints, put each buffer on its own page,
130 130 * to eliminate the performance overhead of trapping to the
131 131 * kernel when modifying a non-watched buffer that shares the
132 132 * page with a watched buffer.
133 133 */
134 134 if (arc_watch && !IS_P2ALIGNED(size, PAGESIZE))
135 135 continue;
136 136 #endif
137 137 if (size <= 4 * SPA_MINBLOCKSIZE) {
138 138 align = SPA_MINBLOCKSIZE;
139 139 } else if (IS_P2ALIGNED(size, PAGESIZE)) {
140 140 align = PAGESIZE;
141 141 } else if (IS_P2ALIGNED(size, p2 >> 2)) {
142 142 align = p2 >> 2;
143 143 }
144 144
145 145 if (align != 0) {
146 146 char name[36];
147 147 (void) sprintf(name, "zio_buf_%lu", (ulong_t)size);
148 148 zio_buf_cache[c] = kmem_cache_create(name, size,
149 149 align, NULL, NULL, NULL, NULL, NULL, cflags);
150 150
151 151 /*
152 152 * Since zio_data bufs do not appear in crash dumps, we
153 153 * pass KMC_NOTOUCH so that no allocator metadata is
154 154 * stored with the buffers.
155 155 */
156 156 (void) sprintf(name, "zio_data_buf_%lu", (ulong_t)size);
157 157 zio_data_buf_cache[c] = kmem_cache_create(name, size,
158 158 align, NULL, NULL, NULL, NULL, data_alloc_arena,
159 159 cflags | KMC_NOTOUCH);
160 160 }
161 161 }
162 162
163 163 while (--c != 0) {
164 164 ASSERT(zio_buf_cache[c] != NULL);
165 165 if (zio_buf_cache[c - 1] == NULL)
166 166 zio_buf_cache[c - 1] = zio_buf_cache[c];
167 167
168 168 ASSERT(zio_data_buf_cache[c] != NULL);
169 169 if (zio_data_buf_cache[c - 1] == NULL)
170 170 zio_data_buf_cache[c - 1] = zio_data_buf_cache[c];
171 171 }
172 172
173 173 /*
174 174 * The zio write taskqs have 1 thread per cpu, allow 1/2 of the taskqs
175 175 * to fail 3 times per txg or 8 failures, whichever is greater.
176 176 */
177 177 if (zfs_mg_alloc_failures == 0)
178 178 zfs_mg_alloc_failures = MAX((3 * max_ncpus / 2), 8);
179 179
180 180 zio_inject_init();
181 181 }
182 182
183 183 void
184 184 zio_fini(void)
185 185 {
186 186 size_t c;
187 187 kmem_cache_t *last_cache = NULL;
188 188 kmem_cache_t *last_data_cache = NULL;
189 189
190 190 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) {
191 191 if (zio_buf_cache[c] != last_cache) {
192 192 last_cache = zio_buf_cache[c];
193 193 kmem_cache_destroy(zio_buf_cache[c]);
194 194 }
195 195 zio_buf_cache[c] = NULL;
196 196
197 197 if (zio_data_buf_cache[c] != last_data_cache) {
198 198 last_data_cache = zio_data_buf_cache[c];
199 199 kmem_cache_destroy(zio_data_buf_cache[c]);
200 200 }
201 201 zio_data_buf_cache[c] = NULL;
202 202 }
203 203
204 204 kmem_cache_destroy(zio_link_cache);
205 205 kmem_cache_destroy(zio_cache);
206 206
207 207 zio_inject_fini();
208 208 }
209 209
210 210 /*
211 211 * ==========================================================================
212 212 * Allocate and free I/O buffers
213 213 * ==========================================================================
214 214 */
215 215
216 216 /*
217 217 * Use zio_buf_alloc to allocate ZFS metadata. This data will appear in a
218 218 * crashdump if the kernel panics, so use it judiciously. Obviously, it's
219 219 * useful to inspect ZFS metadata, but if possible, we should avoid keeping
220 220 * excess / transient data in-core during a crashdump.
221 221 */
222 222 void *
223 223 zio_buf_alloc(size_t size)
224 224 {
225 225 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
226 226
227 227 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
228 228
229 229 return (kmem_cache_alloc(zio_buf_cache[c], KM_PUSHPAGE));
230 230 }
231 231
232 232 /*
233 233 * Use zio_data_buf_alloc to allocate data. The data will not appear in a
234 234 * crashdump if the kernel panics. This exists so that we will limit the amount
235 235 * of ZFS data that shows up in a kernel crashdump. (Thus reducing the amount
236 236 * of kernel heap dumped to disk when the kernel panics)
237 237 */
238 238 void *
239 239 zio_data_buf_alloc(size_t size)
240 240 {
241 241 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
242 242
243 243 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
244 244
245 245 return (kmem_cache_alloc(zio_data_buf_cache[c], KM_PUSHPAGE));
246 246 }
247 247
248 248 void
249 249 zio_buf_free(void *buf, size_t size)
250 250 {
251 251 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
252 252
253 253 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
254 254
255 255 kmem_cache_free(zio_buf_cache[c], buf);
256 256 }
257 257
258 258 void
259 259 zio_data_buf_free(void *buf, size_t size)
260 260 {
261 261 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
262 262
263 263 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
264 264
265 265 kmem_cache_free(zio_data_buf_cache[c], buf);
266 266 }
267 267
268 268 /*
269 269 * ==========================================================================
270 270 * Push and pop I/O transform buffers
271 271 * ==========================================================================
272 272 */
273 273 static void
274 274 zio_push_transform(zio_t *zio, void *data, uint64_t size, uint64_t bufsize,
275 275 zio_transform_func_t *transform)
276 276 {
277 277 zio_transform_t *zt = kmem_alloc(sizeof (zio_transform_t), KM_SLEEP);
278 278
279 279 zt->zt_orig_data = zio->io_data;
280 280 zt->zt_orig_size = zio->io_size;
281 281 zt->zt_bufsize = bufsize;
282 282 zt->zt_transform = transform;
283 283
284 284 zt->zt_next = zio->io_transform_stack;
285 285 zio->io_transform_stack = zt;
286 286
287 287 zio->io_data = data;
288 288 zio->io_size = size;
289 289 }
290 290
291 291 static void
292 292 zio_pop_transforms(zio_t *zio)
293 293 {
294 294 zio_transform_t *zt;
295 295
296 296 while ((zt = zio->io_transform_stack) != NULL) {
297 297 if (zt->zt_transform != NULL)
298 298 zt->zt_transform(zio,
299 299 zt->zt_orig_data, zt->zt_orig_size);
300 300
301 301 if (zt->zt_bufsize != 0)
302 302 zio_buf_free(zio->io_data, zt->zt_bufsize);
303 303
304 304 zio->io_data = zt->zt_orig_data;
305 305 zio->io_size = zt->zt_orig_size;
306 306 zio->io_transform_stack = zt->zt_next;
307 307
308 308 kmem_free(zt, sizeof (zio_transform_t));
309 309 }
310 310 }
311 311
312 312 /*
313 313 * ==========================================================================
314 314 * I/O transform callbacks for subblocks and decompression
315 315 * ==========================================================================
316 316 */
317 317 static void
318 318 zio_subblock(zio_t *zio, void *data, uint64_t size)
319 319 {
320 320 ASSERT(zio->io_size > size);
321 321
322 322 if (zio->io_type == ZIO_TYPE_READ)
323 323 bcopy(zio->io_data, data, size);
324 324 }
325 325
326 326 static void
327 327 zio_decompress(zio_t *zio, void *data, uint64_t size)
328 328 {
329 329 if (zio->io_error == 0 &&
330 330 zio_decompress_data(BP_GET_COMPRESS(zio->io_bp),
331 331 zio->io_data, data, zio->io_size, size) != 0)
332 332 zio->io_error = SET_ERROR(EIO);
333 333 }
334 334
335 335 /*
336 336 * ==========================================================================
337 337 * I/O parent/child relationships and pipeline interlocks
338 338 * ==========================================================================
339 339 */
340 340 /*
341 341 * NOTE - Callers to zio_walk_parents() and zio_walk_children must
342 342 * continue calling these functions until they return NULL.
343 343 * Otherwise, the next caller will pick up the list walk in
344 344 * some indeterminate state. (Otherwise every caller would
345 345 * have to pass in a cookie to keep the state represented by
346 346 * io_walk_link, which gets annoying.)
347 347 */
348 348 zio_t *
349 349 zio_walk_parents(zio_t *cio)
350 350 {
351 351 zio_link_t *zl = cio->io_walk_link;
352 352 list_t *pl = &cio->io_parent_list;
353 353
354 354 zl = (zl == NULL) ? list_head(pl) : list_next(pl, zl);
355 355 cio->io_walk_link = zl;
356 356
357 357 if (zl == NULL)
358 358 return (NULL);
359 359
360 360 ASSERT(zl->zl_child == cio);
361 361 return (zl->zl_parent);
362 362 }
363 363
364 364 zio_t *
365 365 zio_walk_children(zio_t *pio)
366 366 {
367 367 zio_link_t *zl = pio->io_walk_link;
368 368 list_t *cl = &pio->io_child_list;
369 369
370 370 zl = (zl == NULL) ? list_head(cl) : list_next(cl, zl);
371 371 pio->io_walk_link = zl;
372 372
373 373 if (zl == NULL)
374 374 return (NULL);
375 375
376 376 ASSERT(zl->zl_parent == pio);
377 377 return (zl->zl_child);
378 378 }
379 379
380 380 zio_t *
381 381 zio_unique_parent(zio_t *cio)
382 382 {
383 383 zio_t *pio = zio_walk_parents(cio);
384 384
385 385 VERIFY(zio_walk_parents(cio) == NULL);
386 386 return (pio);
387 387 }
388 388
389 389 void
390 390 zio_add_child(zio_t *pio, zio_t *cio)
391 391 {
392 392 zio_link_t *zl = kmem_cache_alloc(zio_link_cache, KM_SLEEP);
393 393
394 394 /*
395 395 * Logical I/Os can have logical, gang, or vdev children.
396 396 * Gang I/Os can have gang or vdev children.
397 397 * Vdev I/Os can only have vdev children.
398 398 * The following ASSERT captures all of these constraints.
399 399 */
400 400 ASSERT(cio->io_child_type <= pio->io_child_type);
401 401
402 402 zl->zl_parent = pio;
403 403 zl->zl_child = cio;
404 404
405 405 mutex_enter(&cio->io_lock);
406 406 mutex_enter(&pio->io_lock);
407 407
408 408 ASSERT(pio->io_state[ZIO_WAIT_DONE] == 0);
409 409
410 410 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
411 411 pio->io_children[cio->io_child_type][w] += !cio->io_state[w];
412 412
413 413 list_insert_head(&pio->io_child_list, zl);
414 414 list_insert_head(&cio->io_parent_list, zl);
415 415
416 416 pio->io_child_count++;
417 417 cio->io_parent_count++;
418 418
419 419 mutex_exit(&pio->io_lock);
420 420 mutex_exit(&cio->io_lock);
421 421 }
422 422
423 423 static void
424 424 zio_remove_child(zio_t *pio, zio_t *cio, zio_link_t *zl)
425 425 {
426 426 ASSERT(zl->zl_parent == pio);
427 427 ASSERT(zl->zl_child == cio);
428 428
429 429 mutex_enter(&cio->io_lock);
430 430 mutex_enter(&pio->io_lock);
431 431
432 432 list_remove(&pio->io_child_list, zl);
433 433 list_remove(&cio->io_parent_list, zl);
434 434
435 435 pio->io_child_count--;
436 436 cio->io_parent_count--;
437 437
438 438 mutex_exit(&pio->io_lock);
439 439 mutex_exit(&cio->io_lock);
440 440
441 441 kmem_cache_free(zio_link_cache, zl);
442 442 }
443 443
444 444 static boolean_t
445 445 zio_wait_for_children(zio_t *zio, enum zio_child child, enum zio_wait_type wait)
446 446 {
447 447 uint64_t *countp = &zio->io_children[child][wait];
448 448 boolean_t waiting = B_FALSE;
449 449
450 450 mutex_enter(&zio->io_lock);
451 451 ASSERT(zio->io_stall == NULL);
452 452 if (*countp != 0) {
453 453 zio->io_stage >>= 1;
454 454 zio->io_stall = countp;
455 455 waiting = B_TRUE;
456 456 }
457 457 mutex_exit(&zio->io_lock);
458 458
459 459 return (waiting);
460 460 }
461 461
462 462 static void
463 463 zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait)
464 464 {
465 465 uint64_t *countp = &pio->io_children[zio->io_child_type][wait];
466 466 int *errorp = &pio->io_child_error[zio->io_child_type];
467 467
468 468 mutex_enter(&pio->io_lock);
469 469 if (zio->io_error && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE))
470 470 *errorp = zio_worst_error(*errorp, zio->io_error);
471 471 pio->io_reexecute |= zio->io_reexecute;
472 472 ASSERT3U(*countp, >, 0);
473 473
474 474 (*countp)--;
475 475
476 476 if (*countp == 0 && pio->io_stall == countp) {
477 477 pio->io_stall = NULL;
478 478 mutex_exit(&pio->io_lock);
479 479 zio_execute(pio);
480 480 } else {
481 481 mutex_exit(&pio->io_lock);
482 482 }
483 483 }
484 484
485 485 static void
486 486 zio_inherit_child_errors(zio_t *zio, enum zio_child c)
487 487 {
488 488 if (zio->io_child_error[c] != 0 && zio->io_error == 0)
489 489 zio->io_error = zio->io_child_error[c];
490 490 }
491 491
492 492 /*
493 493 * ==========================================================================
494 494 * Create the various types of I/O (read, write, free, etc)
495 495 * ==========================================================================
496 496 */
497 497 static zio_t *
498 498 zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
499 499 void *data, uint64_t size, zio_done_func_t *done, void *private,
500 500 zio_type_t type, zio_priority_t priority, enum zio_flag flags,
501 501 vdev_t *vd, uint64_t offset, const zbookmark_t *zb,
502 502 enum zio_stage stage, enum zio_stage pipeline)
503 503 {
504 504 zio_t *zio;
505 505
506 506 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE);
507 507 ASSERT(P2PHASE(size, SPA_MINBLOCKSIZE) == 0);
508 508 ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0);
509 509
510 510 ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER));
511 511 ASSERT(!bp || !(flags & ZIO_FLAG_CONFIG_WRITER));
512 512 ASSERT(vd || stage == ZIO_STAGE_OPEN);
513 513
514 514 zio = kmem_cache_alloc(zio_cache, KM_SLEEP);
515 515 bzero(zio, sizeof (zio_t));
516 516
517 517 mutex_init(&zio->io_lock, NULL, MUTEX_DEFAULT, NULL);
518 518 cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL);
519 519
520 520 list_create(&zio->io_parent_list, sizeof (zio_link_t),
521 521 offsetof(zio_link_t, zl_parent_node));
522 522 list_create(&zio->io_child_list, sizeof (zio_link_t),
523 523 offsetof(zio_link_t, zl_child_node));
524 524
525 525 if (vd != NULL)
526 526 zio->io_child_type = ZIO_CHILD_VDEV;
527 527 else if (flags & ZIO_FLAG_GANG_CHILD)
528 528 zio->io_child_type = ZIO_CHILD_GANG;
529 529 else if (flags & ZIO_FLAG_DDT_CHILD)
530 530 zio->io_child_type = ZIO_CHILD_DDT;
531 531 else
532 532 zio->io_child_type = ZIO_CHILD_LOGICAL;
533 533
534 534 if (bp != NULL) {
535 535 zio->io_bp = (blkptr_t *)bp;
536 536 zio->io_bp_copy = *bp;
537 537 zio->io_bp_orig = *bp;
538 538 if (type != ZIO_TYPE_WRITE ||
539 539 zio->io_child_type == ZIO_CHILD_DDT)
540 540 zio->io_bp = &zio->io_bp_copy; /* so caller can free */
541 541 if (zio->io_child_type == ZIO_CHILD_LOGICAL)
542 542 zio->io_logical = zio;
543 543 if (zio->io_child_type > ZIO_CHILD_GANG && BP_IS_GANG(bp))
544 544 pipeline |= ZIO_GANG_STAGES;
545 545 }
546 546
547 547 zio->io_spa = spa;
548 548 zio->io_txg = txg;
549 549 zio->io_done = done;
550 550 zio->io_private = private;
551 551 zio->io_type = type;
552 552 zio->io_priority = priority;
553 553 zio->io_vd = vd;
554 554 zio->io_offset = offset;
555 555 zio->io_orig_data = zio->io_data = data;
556 556 zio->io_orig_size = zio->io_size = size;
557 557 zio->io_orig_flags = zio->io_flags = flags;
558 558 zio->io_orig_stage = zio->io_stage = stage;
559 559 zio->io_orig_pipeline = zio->io_pipeline = pipeline;
560 560
561 561 zio->io_state[ZIO_WAIT_READY] = (stage >= ZIO_STAGE_READY);
562 562 zio->io_state[ZIO_WAIT_DONE] = (stage >= ZIO_STAGE_DONE);
563 563
564 564 if (zb != NULL)
565 565 zio->io_bookmark = *zb;
566 566
567 567 if (pio != NULL) {
568 568 zio->io_zoneid = pio->io_zoneid;
569 569 if (zio->io_logical == NULL)
570 570 zio->io_logical = pio->io_logical;
571 571 if (zio->io_child_type == ZIO_CHILD_GANG)
572 572 zio->io_gang_leader = pio->io_gang_leader;
573 573 zio_add_child(pio, zio);
574 574 } else {
575 575 zfs_zone_zio_init(zio);
576 576 }
577 577
578 578 return (zio);
579 579 }
580 580
581 581 static void
582 582 zio_destroy(zio_t *zio)
583 583 {
584 584 list_destroy(&zio->io_parent_list);
585 585 list_destroy(&zio->io_child_list);
586 586 mutex_destroy(&zio->io_lock);
587 587 cv_destroy(&zio->io_cv);
588 588 kmem_cache_free(zio_cache, zio);
589 589 }
590 590
591 591 zio_t *
592 592 zio_null(zio_t *pio, spa_t *spa, vdev_t *vd, zio_done_func_t *done,
593 593 void *private, enum zio_flag flags)
594 594 {
595 595 zio_t *zio;
596 596
597 597 zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private,
598 598 ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL,
599 599 ZIO_STAGE_OPEN, ZIO_INTERLOCK_PIPELINE);
600 600
601 601 return (zio);
602 602 }
603 603
604 604 zio_t *
605 605 zio_root(spa_t *spa, zio_done_func_t *done, void *private, enum zio_flag flags)
606 606 {
607 607 return (zio_null(NULL, spa, NULL, done, private, flags));
608 608 }
609 609
610 610 zio_t *
611 611 zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
612 612 void *data, uint64_t size, zio_done_func_t *done, void *private,
613 613 zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb)
614 614 {
615 615 zio_t *zio;
616 616
617 617 zio = zio_create(pio, spa, BP_PHYSICAL_BIRTH(bp), bp,
618 618 data, size, done, private,
619 619 ZIO_TYPE_READ, priority, flags, NULL, 0, zb,
620 620 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ?
621 621 ZIO_DDT_CHILD_READ_PIPELINE : ZIO_READ_PIPELINE);
622 622
623 623 return (zio);
624 624 }
625 625
626 626 zio_t *
627 627 zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
628 628 void *data, uint64_t size, const zio_prop_t *zp,
629 629 zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done,
630 630 void *private,
631 631 zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb)
632 632 {
633 633 zio_t *zio;
634 634
635 635 ASSERT(zp->zp_checksum >= ZIO_CHECKSUM_OFF &&
636 636 zp->zp_checksum < ZIO_CHECKSUM_FUNCTIONS &&
637 637 zp->zp_compress >= ZIO_COMPRESS_OFF &&
638 638 zp->zp_compress < ZIO_COMPRESS_FUNCTIONS &&
639 639 DMU_OT_IS_VALID(zp->zp_type) &&
640 640 zp->zp_level < 32 &&
641 641 zp->zp_copies > 0 &&
642 642 zp->zp_copies <= spa_max_replication(spa));
643 643
644 644 zio = zio_create(pio, spa, txg, bp, data, size, done, private,
645 645 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
646 646 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ?
647 647 ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE);
648 648
649 649 zio->io_ready = ready;
650 650 zio->io_physdone = physdone;
651 651 zio->io_prop = *zp;
652 652
653 653 return (zio);
654 654 }
655 655
656 656 zio_t *
657 657 zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data,
658 658 uint64_t size, zio_done_func_t *done, void *private,
659 659 zio_priority_t priority, enum zio_flag flags, zbookmark_t *zb)
660 660 {
661 661 zio_t *zio;
662 662
663 663 zio = zio_create(pio, spa, txg, bp, data, size, done, private,
664 664 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
665 665 ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE);
666 666
667 667 return (zio);
668 668 }
669 669
670 670 void
671 671 zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite)
672 672 {
673 673 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
674 674 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
675 675 ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
676 676 ASSERT(zio->io_txg == spa_syncing_txg(zio->io_spa));
677 677
678 678 /*
679 679 * We must reset the io_prop to match the values that existed
680 680 * when the bp was first written by dmu_sync() keeping in mind
681 681 * that nopwrite and dedup are mutually exclusive.
682 682 */
683 683 zio->io_prop.zp_dedup = nopwrite ? B_FALSE : zio->io_prop.zp_dedup;
684 684 zio->io_prop.zp_nopwrite = nopwrite;
685 685 zio->io_prop.zp_copies = copies;
686 686 zio->io_bp_override = bp;
687 687 }
688 688
689 689 void
690 690 zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp)
691 691 {
692 692 metaslab_check_free(spa, bp);
693 693
694 694 /*
695 695 * Frees that are for the currently-syncing txg, are not going to be
696 696 * deferred, and which will not need to do a read (i.e. not GANG or
697 697 * DEDUP), can be processed immediately. Otherwise, put them on the
698 698 * in-memory list for later processing.
699 699 */
700 700 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp) ||
701 701 txg != spa->spa_syncing_txg ||
702 702 spa_sync_pass(spa) >= zfs_sync_pass_deferred_free) {
703 703 bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp);
704 704 } else {
705 705 VERIFY0(zio_wait(zio_free_sync(NULL, spa, txg, bp, 0)));
706 706 }
707 707 }
708 708
709 709 zio_t *
710 710 zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
711 711 enum zio_flag flags)
712 712 {
713 713 zio_t *zio;
714 714 enum zio_stage stage = ZIO_FREE_PIPELINE;
715 715
716 716 dprintf_bp(bp, "freeing in txg %llu, pass %u",
717 717 (longlong_t)txg, spa->spa_sync_pass);
718 718
719 719 ASSERT(!BP_IS_HOLE(bp));
720 720 ASSERT(spa_syncing_txg(spa) == txg);
721 721 ASSERT(spa_sync_pass(spa) < zfs_sync_pass_deferred_free);
722 722
723 723 metaslab_check_free(spa, bp);
724 724 arc_freed(spa, bp);
725 725
726 726 /*
727 727 * GANG and DEDUP blocks can induce a read (for the gang block header,
728 728 * or the DDT), so issue them asynchronously so that this thread is
729 729 * not tied up.
730 730 */
731 731 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp))
732 732 stage |= ZIO_STAGE_ISSUE_ASYNC;
733 733
734 734 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
735 735 NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_NOW, flags,
736 736 NULL, 0, NULL, ZIO_STAGE_OPEN, stage);
737 737
738 738
739 739 return (zio);
740 740 }
741 741
742 742 zio_t *
743 743 zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
744 744 zio_done_func_t *done, void *private, enum zio_flag flags)
745 745 {
746 746 zio_t *zio;
747 747
748 748 /*
749 749 * A claim is an allocation of a specific block. Claims are needed
750 750 * to support immediate writes in the intent log. The issue is that
751 751 * immediate writes contain committed data, but in a txg that was
752 752 * *not* committed. Upon opening the pool after an unclean shutdown,
753 753 * the intent log claims all blocks that contain immediate write data
754 754 * so that the SPA knows they're in use.
755 755 *
756 756 * All claims *must* be resolved in the first txg -- before the SPA
757 757 * starts allocating blocks -- so that nothing is allocated twice.
758 758 * If txg == 0 we just verify that the block is claimable.
759 759 */
760 760 ASSERT3U(spa->spa_uberblock.ub_rootbp.blk_birth, <, spa_first_txg(spa));
761 761 ASSERT(txg == spa_first_txg(spa) || txg == 0);
762 762 ASSERT(!BP_GET_DEDUP(bp) || !spa_writeable(spa)); /* zdb(1M) */
763 763
764 764 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
765 765 done, private, ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW, flags,
766 766 NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE);
767 767
768 768 return (zio);
769 769 }
770 770
771 771 zio_t *
772 772 zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
773 773 zio_done_func_t *done, void *private, enum zio_flag flags)
774 774 {
775 775 zio_t *zio;
776 776 int c;
777 777
778 778 if (vd->vdev_children == 0) {
779 779 zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private,
780 780 ZIO_TYPE_IOCTL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL,
781 781 ZIO_STAGE_OPEN, ZIO_IOCTL_PIPELINE);
782 782
783 783 zio->io_cmd = cmd;
784 784 } else {
785 785 zio = zio_null(pio, spa, NULL, NULL, NULL, flags);
786 786
787 787 for (c = 0; c < vd->vdev_children; c++)
788 788 zio_nowait(zio_ioctl(zio, spa, vd->vdev_child[c], cmd,
789 789 done, private, flags));
790 790 }
791 791
792 792 return (zio);
793 793 }
794 794
795 795 zio_t *
796 796 zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
797 797 void *data, int checksum, zio_done_func_t *done, void *private,
798 798 zio_priority_t priority, enum zio_flag flags, boolean_t labels)
799 799 {
800 800 zio_t *zio;
801 801
802 802 ASSERT(vd->vdev_children == 0);
803 803 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
804 804 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
805 805 ASSERT3U(offset + size, <=, vd->vdev_psize);
806 806
807 807 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private,
808 808 ZIO_TYPE_READ, priority, flags, vd, offset, NULL,
809 809 ZIO_STAGE_OPEN, ZIO_READ_PHYS_PIPELINE);
810 810
811 811 zio->io_prop.zp_checksum = checksum;
812 812
813 813 return (zio);
814 814 }
815 815
816 816 zio_t *
817 817 zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
818 818 void *data, int checksum, zio_done_func_t *done, void *private,
819 819 zio_priority_t priority, enum zio_flag flags, boolean_t labels)
820 820 {
821 821 zio_t *zio;
822 822
823 823 ASSERT(vd->vdev_children == 0);
824 824 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
825 825 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
826 826 ASSERT3U(offset + size, <=, vd->vdev_psize);
827 827
828 828 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private,
829 829 ZIO_TYPE_WRITE, priority, flags, vd, offset, NULL,
830 830 ZIO_STAGE_OPEN, ZIO_WRITE_PHYS_PIPELINE);
831 831
832 832 zio->io_prop.zp_checksum = checksum;
833 833
834 834 if (zio_checksum_table[checksum].ci_eck) {
835 835 /*
836 836 * zec checksums are necessarily destructive -- they modify
837 837 * the end of the write buffer to hold the verifier/checksum.
838 838 * Therefore, we must make a local copy in case the data is
839 839 * being written to multiple places in parallel.
840 840 */
841 841 void *wbuf = zio_buf_alloc(size);
842 842 bcopy(data, wbuf, size);
843 843 zio_push_transform(zio, wbuf, size, size, NULL);
844 844 }
845 845
846 846 return (zio);
847 847 }
848 848
849 849 /*
850 850 * Create a child I/O to do some work for us.
851 851 */
852 852 zio_t *
853 853 zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset,
854 854 void *data, uint64_t size, int type, zio_priority_t priority,
855 855 enum zio_flag flags, zio_done_func_t *done, void *private)
856 856 {
857 857 enum zio_stage pipeline = ZIO_VDEV_CHILD_PIPELINE;
858 858 zio_t *zio;
859 859
860 860 ASSERT(vd->vdev_parent ==
861 861 (pio->io_vd ? pio->io_vd : pio->io_spa->spa_root_vdev));
862 862
863 863 if (type == ZIO_TYPE_READ && bp != NULL) {
864 864 /*
865 865 * If we have the bp, then the child should perform the
866 866 * checksum and the parent need not. This pushes error
867 867 * detection as close to the leaves as possible and
868 868 * eliminates redundant checksums in the interior nodes.
869 869 */
870 870 pipeline |= ZIO_STAGE_CHECKSUM_VERIFY;
871 871 pio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY;
872 872 }
873 873
874 874 if (vd->vdev_children == 0)
875 875 offset += VDEV_LABEL_START_SIZE;
876 876
877 877 flags |= ZIO_VDEV_CHILD_FLAGS(pio) | ZIO_FLAG_DONT_PROPAGATE;
878 878
879 879 /*
880 880 * If we've decided to do a repair, the write is not speculative --
881 881 * even if the original read was.
882 882 */
883 883 if (flags & ZIO_FLAG_IO_REPAIR)
884 884 flags &= ~ZIO_FLAG_SPECULATIVE;
885 885
886 886 zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size,
887 887 done, private, type, priority, flags, vd, offset, &pio->io_bookmark,
888 888 ZIO_STAGE_VDEV_IO_START >> 1, pipeline);
889 889
890 890 zio->io_physdone = pio->io_physdone;
891 891 if (vd->vdev_ops->vdev_op_leaf && zio->io_logical != NULL)
892 892 zio->io_logical->io_phys_children++;
893 893
894 894 return (zio);
895 895 }
896 896
897 897 zio_t *
898 898 zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, void *data, uint64_t size,
899 899 int type, zio_priority_t priority, enum zio_flag flags,
900 900 zio_done_func_t *done, void *private)
901 901 {
902 902 zio_t *zio;
903 903
904 904 ASSERT(vd->vdev_ops->vdev_op_leaf);
905 905
906 906 zio = zio_create(NULL, vd->vdev_spa, 0, NULL,
907 907 data, size, done, private, type, priority,
908 908 flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED,
909 909 vd, offset, NULL,
910 910 ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE);
911 911
912 912 return (zio);
913 913 }
914 914
915 915 void
916 916 zio_flush(zio_t *zio, vdev_t *vd)
917 917 {
918 918 zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE,
919 919 NULL, NULL,
920 920 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY));
921 921 }
922 922
923 923 void
924 924 zio_shrink(zio_t *zio, uint64_t size)
925 925 {
926 926 ASSERT(zio->io_executor == NULL);
927 927 ASSERT(zio->io_orig_size == zio->io_size);
928 928 ASSERT(size <= zio->io_size);
929 929
930 930 /*
931 931 * We don't shrink for raidz because of problems with the
932 932 * reconstruction when reading back less than the block size.
933 933 * Note, BP_IS_RAIDZ() assumes no compression.
934 934 */
935 935 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF);
936 936 if (!BP_IS_RAIDZ(zio->io_bp))
937 937 zio->io_orig_size = zio->io_size = size;
938 938 }
939 939
940 940 /*
941 941 * ==========================================================================
942 942 * Prepare to read and write logical blocks
943 943 * ==========================================================================
944 944 */
945 945
946 946 static int
947 947 zio_read_bp_init(zio_t *zio)
948 948 {
949 949 blkptr_t *bp = zio->io_bp;
950 950
951 951 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF &&
952 952 zio->io_child_type == ZIO_CHILD_LOGICAL &&
953 953 !(zio->io_flags & ZIO_FLAG_RAW)) {
954 954 uint64_t psize = BP_GET_PSIZE(bp);
955 955 void *cbuf = zio_buf_alloc(psize);
956 956
957 957 zio_push_transform(zio, cbuf, psize, psize, zio_decompress);
958 958 }
959 959
960 960 if (!DMU_OT_IS_METADATA(BP_GET_TYPE(bp)) && BP_GET_LEVEL(bp) == 0)
961 961 zio->io_flags |= ZIO_FLAG_DONT_CACHE;
962 962
963 963 if (BP_GET_TYPE(bp) == DMU_OT_DDT_ZAP)
964 964 zio->io_flags |= ZIO_FLAG_DONT_CACHE;
965 965
966 966 if (BP_GET_DEDUP(bp) && zio->io_child_type == ZIO_CHILD_LOGICAL)
967 967 zio->io_pipeline = ZIO_DDT_READ_PIPELINE;
968 968
969 969 return (ZIO_PIPELINE_CONTINUE);
970 970 }
971 971
972 972 static int
973 973 zio_write_bp_init(zio_t *zio)
974 974 {
975 975 spa_t *spa = zio->io_spa;
976 976 zio_prop_t *zp = &zio->io_prop;
977 977 enum zio_compress compress = zp->zp_compress;
978 978 blkptr_t *bp = zio->io_bp;
979 979 uint64_t lsize = zio->io_size;
980 980 uint64_t psize = lsize;
981 981 int pass = 1;
982 982
983 983 /*
984 984 * If our children haven't all reached the ready stage,
985 985 * wait for them and then repeat this pipeline stage.
986 986 */
987 987 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
988 988 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_READY))
989 989 return (ZIO_PIPELINE_STOP);
990 990
991 991 if (!IO_IS_ALLOCATING(zio))
992 992 return (ZIO_PIPELINE_CONTINUE);
993 993
994 994 ASSERT(zio->io_child_type != ZIO_CHILD_DDT);
995 995
996 996 if (zio->io_bp_override) {
997 997 ASSERT(bp->blk_birth != zio->io_txg);
998 998 ASSERT(BP_GET_DEDUP(zio->io_bp_override) == 0);
999 999
1000 1000 *bp = *zio->io_bp_override;
1001 1001 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1002 1002
1003 1003 /*
1004 1004 * If we've been overridden and nopwrite is set then
1005 1005 * set the flag accordingly to indicate that a nopwrite
1006 1006 * has already occurred.
1007 1007 */
1008 1008 if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) {
1009 1009 ASSERT(!zp->zp_dedup);
1010 1010 zio->io_flags |= ZIO_FLAG_NOPWRITE;
1011 1011 return (ZIO_PIPELINE_CONTINUE);
1012 1012 }
1013 1013
1014 1014 ASSERT(!zp->zp_nopwrite);
1015 1015
1016 1016 if (BP_IS_HOLE(bp) || !zp->zp_dedup)
1017 1017 return (ZIO_PIPELINE_CONTINUE);
1018 1018
1019 1019 ASSERT(zio_checksum_table[zp->zp_checksum].ci_dedup ||
1020 1020 zp->zp_dedup_verify);
1021 1021
1022 1022 if (BP_GET_CHECKSUM(bp) == zp->zp_checksum) {
1023 1023 BP_SET_DEDUP(bp, 1);
1024 1024 zio->io_pipeline |= ZIO_STAGE_DDT_WRITE;
1025 1025 return (ZIO_PIPELINE_CONTINUE);
1026 1026 }
1027 1027 zio->io_bp_override = NULL;
1028 1028 BP_ZERO(bp);
1029 1029 }
1030 1030
1031 1031 if (!BP_IS_HOLE(bp) && bp->blk_birth == zio->io_txg) {
1032 1032 /*
1033 1033 * We're rewriting an existing block, which means we're
1034 1034 * working on behalf of spa_sync(). For spa_sync() to
1035 1035 * converge, it must eventually be the case that we don't
1036 1036 * have to allocate new blocks. But compression changes
1037 1037 * the blocksize, which forces a reallocate, and makes
1038 1038 * convergence take longer. Therefore, after the first
1039 1039 * few passes, stop compressing to ensure convergence.
1040 1040 */
1041 1041 pass = spa_sync_pass(spa);
1042 1042
1043 1043 ASSERT(zio->io_txg == spa_syncing_txg(spa));
1044 1044 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1045 1045 ASSERT(!BP_GET_DEDUP(bp));
1046 1046
1047 1047 if (pass >= zfs_sync_pass_dont_compress)
1048 1048 compress = ZIO_COMPRESS_OFF;
1049 1049
1050 1050 /* Make sure someone doesn't change their mind on overwrites */
1051 1051 ASSERT(MIN(zp->zp_copies + BP_IS_GANG(bp),
1052 1052 spa_max_replication(spa)) == BP_GET_NDVAS(bp));
1053 1053 }
1054 1054
1055 1055 if (compress != ZIO_COMPRESS_OFF) {
1056 1056 void *cbuf = zio_buf_alloc(lsize);
1057 1057 psize = zio_compress_data(compress, zio->io_data, cbuf, lsize);
1058 1058 if (psize == 0 || psize == lsize) {
1059 1059 compress = ZIO_COMPRESS_OFF;
1060 1060 zio_buf_free(cbuf, lsize);
1061 1061 } else {
1062 1062 ASSERT(psize < lsize);
1063 1063 zio_push_transform(zio, cbuf, psize, lsize, NULL);
1064 1064 }
1065 1065 }
1066 1066
1067 1067 /*
1068 1068 * The final pass of spa_sync() must be all rewrites, but the first
1069 1069 * few passes offer a trade-off: allocating blocks defers convergence,
1070 1070 * but newly allocated blocks are sequential, so they can be written
1071 1071 * to disk faster. Therefore, we allow the first few passes of
1072 1072 * spa_sync() to allocate new blocks, but force rewrites after that.
1073 1073 * There should only be a handful of blocks after pass 1 in any case.
1074 1074 */
1075 1075 if (!BP_IS_HOLE(bp) && bp->blk_birth == zio->io_txg &&
1076 1076 BP_GET_PSIZE(bp) == psize &&
1077 1077 pass >= zfs_sync_pass_rewrite) {
1078 1078 ASSERT(psize != 0);
1079 1079 enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES;
1080 1080 zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages;
1081 1081 zio->io_flags |= ZIO_FLAG_IO_REWRITE;
1082 1082 } else {
1083 1083 BP_ZERO(bp);
1084 1084 zio->io_pipeline = ZIO_WRITE_PIPELINE;
1085 1085 }
1086 1086
1087 1087 if (psize == 0) {
1088 1088 if (zio->io_bp_orig.blk_birth != 0 &&
1089 1089 spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) {
1090 1090 BP_SET_LSIZE(bp, lsize);
1091 1091 BP_SET_TYPE(bp, zp->zp_type);
1092 1092 BP_SET_LEVEL(bp, zp->zp_level);
1093 1093 BP_SET_BIRTH(bp, zio->io_txg, 0);
1094 1094 }
1095 1095 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1096 1096 } else {
1097 1097 ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER);
1098 1098 BP_SET_LSIZE(bp, lsize);
1099 1099 BP_SET_TYPE(bp, zp->zp_type);
1100 1100 BP_SET_LEVEL(bp, zp->zp_level);
1101 1101 BP_SET_PSIZE(bp, psize);
1102 1102 BP_SET_COMPRESS(bp, compress);
1103 1103 BP_SET_CHECKSUM(bp, zp->zp_checksum);
1104 1104 BP_SET_DEDUP(bp, zp->zp_dedup);
1105 1105 BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
1106 1106 if (zp->zp_dedup) {
1107 1107 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1108 1108 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1109 1109 zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE;
1110 1110 }
1111 1111 if (zp->zp_nopwrite) {
1112 1112 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1113 1113 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1114 1114 zio->io_pipeline |= ZIO_STAGE_NOP_WRITE;
1115 1115 }
1116 1116 }
1117 1117
1118 1118 return (ZIO_PIPELINE_CONTINUE);
1119 1119 }
1120 1120
1121 1121 static int
1122 1122 zio_free_bp_init(zio_t *zio)
1123 1123 {
1124 1124 blkptr_t *bp = zio->io_bp;
1125 1125
1126 1126 if (zio->io_child_type == ZIO_CHILD_LOGICAL) {
1127 1127 if (BP_GET_DEDUP(bp))
1128 1128 zio->io_pipeline = ZIO_DDT_FREE_PIPELINE;
1129 1129 }
1130 1130
1131 1131 return (ZIO_PIPELINE_CONTINUE);
1132 1132 }
1133 1133
1134 1134 /*
1135 1135 * ==========================================================================
1136 1136 * Execute the I/O pipeline
1137 1137 * ==========================================================================
1138 1138 */
1139 1139
1140 1140 static void
1141 1141 zio_taskq_dispatch(zio_t *zio, zio_taskq_type_t q, boolean_t cutinline)
1142 1142 {
1143 1143 spa_t *spa = zio->io_spa;
1144 1144 zio_type_t t = zio->io_type;
1145 1145 int flags = (cutinline ? TQ_FRONT : 0);
1146 1146
1147 1147 /*
1148 1148 * If we're a config writer or a probe, the normal issue and
1149 1149 * interrupt threads may all be blocked waiting for the config lock.
1150 1150 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL.
1151 1151 */
1152 1152 if (zio->io_flags & (ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_PROBE))
1153 1153 t = ZIO_TYPE_NULL;
1154 1154
1155 1155 /*
1156 1156 * A similar issue exists for the L2ARC write thread until L2ARC 2.0.
1157 1157 */
1158 1158 if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux)
1159 1159 t = ZIO_TYPE_NULL;
1160 1160
1161 1161 /*
1162 1162 * If this is a high priority I/O, then use the high priority taskq if
1163 1163 * available.
1164 1164 */
1165 1165 if (zio->io_priority == ZIO_PRIORITY_NOW &&
1166 1166 spa->spa_zio_taskq[t][q + 1].stqs_count != 0)
1167 1167 q++;
1168 1168
1169 1169 ASSERT3U(q, <, ZIO_TASKQ_TYPES);
1170 1170
1171 1171 /*
1172 1172 * NB: We are assuming that the zio can only be dispatched
1173 1173 * to a single taskq at a time. It would be a grievous error
1174 1174 * to dispatch the zio to another taskq at the same time.
1175 1175 */
1176 1176 ASSERT(zio->io_tqent.tqent_next == NULL);
1177 1177 spa_taskq_dispatch_ent(spa, t, q, (task_func_t *)zio_execute, zio,
1178 1178 flags, &zio->io_tqent);
1179 1179 }
1180 1180
1181 1181 static boolean_t
1182 1182 zio_taskq_member(zio_t *zio, zio_taskq_type_t q)
1183 1183 {
1184 1184 kthread_t *executor = zio->io_executor;
1185 1185 spa_t *spa = zio->io_spa;
1186 1186
1187 1187 for (zio_type_t t = 0; t < ZIO_TYPES; t++) {
1188 1188 spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q];
1189 1189 uint_t i;
1190 1190 for (i = 0; i < tqs->stqs_count; i++) {
1191 1191 if (taskq_member(tqs->stqs_taskq[i], executor))
1192 1192 return (B_TRUE);
1193 1193 }
1194 1194 }
1195 1195
1196 1196 return (B_FALSE);
1197 1197 }
1198 1198
1199 1199 static int
1200 1200 zio_issue_async(zio_t *zio)
1201 1201 {
1202 1202 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE);
1203 1203
1204 1204 return (ZIO_PIPELINE_STOP);
1205 1205 }
1206 1206
1207 1207 void
1208 1208 zio_interrupt(zio_t *zio)
1209 1209 {
1210 1210 zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE);
1211 1211 }
1212 1212
1213 1213 /*
1214 1214 * Execute the I/O pipeline until one of the following occurs:
1215 1215 *
1216 1216 * (1) the I/O completes
1217 1217 * (2) the pipeline stalls waiting for dependent child I/Os
1218 1218 * (3) the I/O issues, so we're waiting for an I/O completion interrupt
1219 1219 * (4) the I/O is delegated by vdev-level caching or aggregation
1220 1220 * (5) the I/O is deferred due to vdev-level queueing
1221 1221 * (6) the I/O is handed off to another thread.
1222 1222 *
1223 1223 * In all cases, the pipeline stops whenever there's no CPU work; it never
1224 1224 * burns a thread in cv_wait().
1225 1225 *
1226 1226 * There's no locking on io_stage because there's no legitimate way
1227 1227 * for multiple threads to be attempting to process the same I/O.
1228 1228 */
1229 1229 static zio_pipe_stage_t *zio_pipeline[];
1230 1230
1231 1231 void
1232 1232 zio_execute(zio_t *zio)
1233 1233 {
1234 1234 zio->io_executor = curthread;
1235 1235
1236 1236 while (zio->io_stage < ZIO_STAGE_DONE) {
1237 1237 enum zio_stage pipeline = zio->io_pipeline;
1238 1238 enum zio_stage stage = zio->io_stage;
1239 1239 int rv;
1240 1240
1241 1241 ASSERT(!MUTEX_HELD(&zio->io_lock));
1242 1242 ASSERT(ISP2(stage));
1243 1243 ASSERT(zio->io_stall == NULL);
1244 1244
1245 1245 do {
1246 1246 stage <<= 1;
1247 1247 } while ((stage & pipeline) == 0);
1248 1248
1249 1249 ASSERT(stage <= ZIO_STAGE_DONE);
1250 1250
1251 1251 /*
1252 1252 * If we are in interrupt context and this pipeline stage
1253 1253 * will grab a config lock that is held across I/O,
1254 1254 * or may wait for an I/O that needs an interrupt thread
1255 1255 * to complete, issue async to avoid deadlock.
1256 1256 *
1257 1257 * For VDEV_IO_START, we cut in line so that the io will
1258 1258 * be sent to disk promptly.
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1259 1259 */
1260 1260 if ((stage & ZIO_BLOCKING_STAGES) && zio->io_vd == NULL &&
1261 1261 zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) {
1262 1262 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ?
1263 1263 zio_requeue_io_start_cut_in_line : B_FALSE;
1264 1264 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut);
1265 1265 return;
1266 1266 }
1267 1267
1268 1268 zio->io_stage = stage;
1269 - rv = zio_pipeline[highbit(stage) - 1](zio);
1269 + rv = zio_pipeline[highbit64(stage) - 1](zio);
1270 1270
1271 1271 if (rv == ZIO_PIPELINE_STOP)
1272 1272 return;
1273 1273
1274 1274 ASSERT(rv == ZIO_PIPELINE_CONTINUE);
1275 1275 }
1276 1276 }
1277 1277
1278 1278 /*
1279 1279 * ==========================================================================
1280 1280 * Initiate I/O, either sync or async
1281 1281 * ==========================================================================
1282 1282 */
1283 1283 int
1284 1284 zio_wait(zio_t *zio)
1285 1285 {
1286 1286 int error;
1287 1287
1288 1288 ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
1289 1289 ASSERT(zio->io_executor == NULL);
1290 1290
1291 1291 zio->io_waiter = curthread;
1292 1292
1293 1293 zio_execute(zio);
1294 1294
1295 1295 mutex_enter(&zio->io_lock);
1296 1296 while (zio->io_executor != NULL)
1297 1297 cv_wait(&zio->io_cv, &zio->io_lock);
1298 1298 mutex_exit(&zio->io_lock);
1299 1299
1300 1300 error = zio->io_error;
1301 1301 zio_destroy(zio);
1302 1302
1303 1303 return (error);
1304 1304 }
1305 1305
1306 1306 void
1307 1307 zio_nowait(zio_t *zio)
1308 1308 {
1309 1309 ASSERT(zio->io_executor == NULL);
1310 1310
1311 1311 if (zio->io_child_type == ZIO_CHILD_LOGICAL &&
1312 1312 zio_unique_parent(zio) == NULL) {
1313 1313 /*
1314 1314 * This is a logical async I/O with no parent to wait for it.
1315 1315 * We add it to the spa_async_root_zio "Godfather" I/O which
1316 1316 * will ensure they complete prior to unloading the pool.
1317 1317 */
1318 1318 spa_t *spa = zio->io_spa;
1319 1319
1320 1320 zio_add_child(spa->spa_async_zio_root, zio);
1321 1321 }
1322 1322
1323 1323 zio_execute(zio);
1324 1324 }
1325 1325
1326 1326 /*
1327 1327 * ==========================================================================
1328 1328 * Reexecute or suspend/resume failed I/O
1329 1329 * ==========================================================================
1330 1330 */
1331 1331
1332 1332 static void
1333 1333 zio_reexecute(zio_t *pio)
1334 1334 {
1335 1335 zio_t *cio, *cio_next;
1336 1336
1337 1337 ASSERT(pio->io_child_type == ZIO_CHILD_LOGICAL);
1338 1338 ASSERT(pio->io_orig_stage == ZIO_STAGE_OPEN);
1339 1339 ASSERT(pio->io_gang_leader == NULL);
1340 1340 ASSERT(pio->io_gang_tree == NULL);
1341 1341
1342 1342 pio->io_flags = pio->io_orig_flags;
1343 1343 pio->io_stage = pio->io_orig_stage;
1344 1344 pio->io_pipeline = pio->io_orig_pipeline;
1345 1345 pio->io_reexecute = 0;
1346 1346 pio->io_flags |= ZIO_FLAG_REEXECUTED;
1347 1347 pio->io_error = 0;
1348 1348 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
1349 1349 pio->io_state[w] = 0;
1350 1350 for (int c = 0; c < ZIO_CHILD_TYPES; c++)
1351 1351 pio->io_child_error[c] = 0;
1352 1352
1353 1353 if (IO_IS_ALLOCATING(pio))
1354 1354 BP_ZERO(pio->io_bp);
1355 1355
1356 1356 /*
1357 1357 * As we reexecute pio's children, new children could be created.
1358 1358 * New children go to the head of pio's io_child_list, however,
1359 1359 * so we will (correctly) not reexecute them. The key is that
1360 1360 * the remainder of pio's io_child_list, from 'cio_next' onward,
1361 1361 * cannot be affected by any side effects of reexecuting 'cio'.
1362 1362 */
1363 1363 for (cio = zio_walk_children(pio); cio != NULL; cio = cio_next) {
1364 1364 cio_next = zio_walk_children(pio);
1365 1365 mutex_enter(&pio->io_lock);
1366 1366 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
1367 1367 pio->io_children[cio->io_child_type][w]++;
1368 1368 mutex_exit(&pio->io_lock);
1369 1369 zio_reexecute(cio);
1370 1370 }
1371 1371
1372 1372 /*
1373 1373 * Now that all children have been reexecuted, execute the parent.
1374 1374 * We don't reexecute "The Godfather" I/O here as it's the
1375 1375 * responsibility of the caller to wait on him.
1376 1376 */
1377 1377 if (!(pio->io_flags & ZIO_FLAG_GODFATHER))
1378 1378 zio_execute(pio);
1379 1379 }
1380 1380
1381 1381 void
1382 1382 zio_suspend(spa_t *spa, zio_t *zio)
1383 1383 {
1384 1384 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC)
1385 1385 fm_panic("Pool '%s' has encountered an uncorrectable I/O "
1386 1386 "failure and the failure mode property for this pool "
1387 1387 "is set to panic.", spa_name(spa));
1388 1388
1389 1389 zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, NULL, 0, 0);
1390 1390
1391 1391 mutex_enter(&spa->spa_suspend_lock);
1392 1392
1393 1393 if (spa->spa_suspend_zio_root == NULL)
1394 1394 spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL,
1395 1395 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE |
1396 1396 ZIO_FLAG_GODFATHER);
1397 1397
1398 1398 spa->spa_suspended = B_TRUE;
1399 1399
1400 1400 if (zio != NULL) {
1401 1401 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER));
1402 1402 ASSERT(zio != spa->spa_suspend_zio_root);
1403 1403 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1404 1404 ASSERT(zio_unique_parent(zio) == NULL);
1405 1405 ASSERT(zio->io_stage == ZIO_STAGE_DONE);
1406 1406 zio_add_child(spa->spa_suspend_zio_root, zio);
1407 1407 }
1408 1408
1409 1409 mutex_exit(&spa->spa_suspend_lock);
1410 1410 }
1411 1411
1412 1412 int
1413 1413 zio_resume(spa_t *spa)
1414 1414 {
1415 1415 zio_t *pio;
1416 1416
1417 1417 /*
1418 1418 * Reexecute all previously suspended i/o.
1419 1419 */
1420 1420 mutex_enter(&spa->spa_suspend_lock);
1421 1421 spa->spa_suspended = B_FALSE;
1422 1422 cv_broadcast(&spa->spa_suspend_cv);
1423 1423 pio = spa->spa_suspend_zio_root;
1424 1424 spa->spa_suspend_zio_root = NULL;
1425 1425 mutex_exit(&spa->spa_suspend_lock);
1426 1426
1427 1427 if (pio == NULL)
1428 1428 return (0);
1429 1429
1430 1430 zio_reexecute(pio);
1431 1431 return (zio_wait(pio));
1432 1432 }
1433 1433
1434 1434 void
1435 1435 zio_resume_wait(spa_t *spa)
1436 1436 {
1437 1437 mutex_enter(&spa->spa_suspend_lock);
1438 1438 while (spa_suspended(spa))
1439 1439 cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock);
1440 1440 mutex_exit(&spa->spa_suspend_lock);
1441 1441 }
1442 1442
1443 1443 /*
1444 1444 * ==========================================================================
1445 1445 * Gang blocks.
1446 1446 *
1447 1447 * A gang block is a collection of small blocks that looks to the DMU
1448 1448 * like one large block. When zio_dva_allocate() cannot find a block
1449 1449 * of the requested size, due to either severe fragmentation or the pool
1450 1450 * being nearly full, it calls zio_write_gang_block() to construct the
1451 1451 * block from smaller fragments.
1452 1452 *
1453 1453 * A gang block consists of a gang header (zio_gbh_phys_t) and up to
1454 1454 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like
1455 1455 * an indirect block: it's an array of block pointers. It consumes
1456 1456 * only one sector and hence is allocatable regardless of fragmentation.
1457 1457 * The gang header's bps point to its gang members, which hold the data.
1458 1458 *
1459 1459 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg>
1460 1460 * as the verifier to ensure uniqueness of the SHA256 checksum.
1461 1461 * Critically, the gang block bp's blk_cksum is the checksum of the data,
1462 1462 * not the gang header. This ensures that data block signatures (needed for
1463 1463 * deduplication) are independent of how the block is physically stored.
1464 1464 *
1465 1465 * Gang blocks can be nested: a gang member may itself be a gang block.
1466 1466 * Thus every gang block is a tree in which root and all interior nodes are
1467 1467 * gang headers, and the leaves are normal blocks that contain user data.
1468 1468 * The root of the gang tree is called the gang leader.
1469 1469 *
1470 1470 * To perform any operation (read, rewrite, free, claim) on a gang block,
1471 1471 * zio_gang_assemble() first assembles the gang tree (minus data leaves)
1472 1472 * in the io_gang_tree field of the original logical i/o by recursively
1473 1473 * reading the gang leader and all gang headers below it. This yields
1474 1474 * an in-core tree containing the contents of every gang header and the
1475 1475 * bps for every constituent of the gang block.
1476 1476 *
1477 1477 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree
1478 1478 * and invokes a callback on each bp. To free a gang block, zio_gang_issue()
1479 1479 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp.
1480 1480 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim().
1481 1481 * zio_read_gang() is a wrapper around zio_read() that omits reading gang
1482 1482 * headers, since we already have those in io_gang_tree. zio_rewrite_gang()
1483 1483 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite()
1484 1484 * of the gang header plus zio_checksum_compute() of the data to update the
1485 1485 * gang header's blk_cksum as described above.
1486 1486 *
1487 1487 * The two-phase assemble/issue model solves the problem of partial failure --
1488 1488 * what if you'd freed part of a gang block but then couldn't read the
1489 1489 * gang header for another part? Assembling the entire gang tree first
1490 1490 * ensures that all the necessary gang header I/O has succeeded before
1491 1491 * starting the actual work of free, claim, or write. Once the gang tree
1492 1492 * is assembled, free and claim are in-memory operations that cannot fail.
1493 1493 *
1494 1494 * In the event that a gang write fails, zio_dva_unallocate() walks the
1495 1495 * gang tree to immediately free (i.e. insert back into the space map)
1496 1496 * everything we've allocated. This ensures that we don't get ENOSPC
1497 1497 * errors during repeated suspend/resume cycles due to a flaky device.
1498 1498 *
1499 1499 * Gang rewrites only happen during sync-to-convergence. If we can't assemble
1500 1500 * the gang tree, we won't modify the block, so we can safely defer the free
1501 1501 * (knowing that the block is still intact). If we *can* assemble the gang
1502 1502 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free
1503 1503 * each constituent bp and we can allocate a new block on the next sync pass.
1504 1504 *
1505 1505 * In all cases, the gang tree allows complete recovery from partial failure.
1506 1506 * ==========================================================================
1507 1507 */
1508 1508
1509 1509 static zio_t *
1510 1510 zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1511 1511 {
1512 1512 if (gn != NULL)
1513 1513 return (pio);
1514 1514
1515 1515 return (zio_read(pio, pio->io_spa, bp, data, BP_GET_PSIZE(bp),
1516 1516 NULL, NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
1517 1517 &pio->io_bookmark));
1518 1518 }
1519 1519
1520 1520 zio_t *
1521 1521 zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1522 1522 {
1523 1523 zio_t *zio;
1524 1524
1525 1525 if (gn != NULL) {
1526 1526 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
1527 1527 gn->gn_gbh, SPA_GANGBLOCKSIZE, NULL, NULL, pio->io_priority,
1528 1528 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
1529 1529 /*
1530 1530 * As we rewrite each gang header, the pipeline will compute
1531 1531 * a new gang block header checksum for it; but no one will
1532 1532 * compute a new data checksum, so we do that here. The one
1533 1533 * exception is the gang leader: the pipeline already computed
1534 1534 * its data checksum because that stage precedes gang assembly.
1535 1535 * (Presently, nothing actually uses interior data checksums;
1536 1536 * this is just good hygiene.)
1537 1537 */
1538 1538 if (gn != pio->io_gang_leader->io_gang_tree) {
1539 1539 zio_checksum_compute(zio, BP_GET_CHECKSUM(bp),
1540 1540 data, BP_GET_PSIZE(bp));
1541 1541 }
1542 1542 /*
1543 1543 * If we are here to damage data for testing purposes,
1544 1544 * leave the GBH alone so that we can detect the damage.
1545 1545 */
1546 1546 if (pio->io_gang_leader->io_flags & ZIO_FLAG_INDUCE_DAMAGE)
1547 1547 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
1548 1548 } else {
1549 1549 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
1550 1550 data, BP_GET_PSIZE(bp), NULL, NULL, pio->io_priority,
1551 1551 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
1552 1552 }
1553 1553
1554 1554 return (zio);
1555 1555 }
1556 1556
1557 1557 /* ARGSUSED */
1558 1558 zio_t *
1559 1559 zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1560 1560 {
1561 1561 return (zio_free_sync(pio, pio->io_spa, pio->io_txg, bp,
1562 1562 ZIO_GANG_CHILD_FLAGS(pio)));
1563 1563 }
1564 1564
1565 1565 /* ARGSUSED */
1566 1566 zio_t *
1567 1567 zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1568 1568 {
1569 1569 return (zio_claim(pio, pio->io_spa, pio->io_txg, bp,
1570 1570 NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)));
1571 1571 }
1572 1572
1573 1573 static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = {
1574 1574 NULL,
1575 1575 zio_read_gang,
1576 1576 zio_rewrite_gang,
1577 1577 zio_free_gang,
1578 1578 zio_claim_gang,
1579 1579 NULL
1580 1580 };
1581 1581
1582 1582 static void zio_gang_tree_assemble_done(zio_t *zio);
1583 1583
1584 1584 static zio_gang_node_t *
1585 1585 zio_gang_node_alloc(zio_gang_node_t **gnpp)
1586 1586 {
1587 1587 zio_gang_node_t *gn;
1588 1588
1589 1589 ASSERT(*gnpp == NULL);
1590 1590
1591 1591 gn = kmem_zalloc(sizeof (*gn), KM_SLEEP);
1592 1592 gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE);
1593 1593 *gnpp = gn;
1594 1594
1595 1595 return (gn);
1596 1596 }
1597 1597
1598 1598 static void
1599 1599 zio_gang_node_free(zio_gang_node_t **gnpp)
1600 1600 {
1601 1601 zio_gang_node_t *gn = *gnpp;
1602 1602
1603 1603 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++)
1604 1604 ASSERT(gn->gn_child[g] == NULL);
1605 1605
1606 1606 zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE);
1607 1607 kmem_free(gn, sizeof (*gn));
1608 1608 *gnpp = NULL;
1609 1609 }
1610 1610
1611 1611 static void
1612 1612 zio_gang_tree_free(zio_gang_node_t **gnpp)
1613 1613 {
1614 1614 zio_gang_node_t *gn = *gnpp;
1615 1615
1616 1616 if (gn == NULL)
1617 1617 return;
1618 1618
1619 1619 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++)
1620 1620 zio_gang_tree_free(&gn->gn_child[g]);
1621 1621
1622 1622 zio_gang_node_free(gnpp);
1623 1623 }
1624 1624
1625 1625 static void
1626 1626 zio_gang_tree_assemble(zio_t *gio, blkptr_t *bp, zio_gang_node_t **gnpp)
1627 1627 {
1628 1628 zio_gang_node_t *gn = zio_gang_node_alloc(gnpp);
1629 1629
1630 1630 ASSERT(gio->io_gang_leader == gio);
1631 1631 ASSERT(BP_IS_GANG(bp));
1632 1632
1633 1633 zio_nowait(zio_read(gio, gio->io_spa, bp, gn->gn_gbh,
1634 1634 SPA_GANGBLOCKSIZE, zio_gang_tree_assemble_done, gn,
1635 1635 gio->io_priority, ZIO_GANG_CHILD_FLAGS(gio), &gio->io_bookmark));
1636 1636 }
1637 1637
1638 1638 static void
1639 1639 zio_gang_tree_assemble_done(zio_t *zio)
1640 1640 {
1641 1641 zio_t *gio = zio->io_gang_leader;
1642 1642 zio_gang_node_t *gn = zio->io_private;
1643 1643 blkptr_t *bp = zio->io_bp;
1644 1644
1645 1645 ASSERT(gio == zio_unique_parent(zio));
1646 1646 ASSERT(zio->io_child_count == 0);
1647 1647
1648 1648 if (zio->io_error)
1649 1649 return;
1650 1650
1651 1651 if (BP_SHOULD_BYTESWAP(bp))
1652 1652 byteswap_uint64_array(zio->io_data, zio->io_size);
1653 1653
1654 1654 ASSERT(zio->io_data == gn->gn_gbh);
1655 1655 ASSERT(zio->io_size == SPA_GANGBLOCKSIZE);
1656 1656 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC);
1657 1657
1658 1658 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
1659 1659 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
1660 1660 if (!BP_IS_GANG(gbp))
1661 1661 continue;
1662 1662 zio_gang_tree_assemble(gio, gbp, &gn->gn_child[g]);
1663 1663 }
1664 1664 }
1665 1665
1666 1666 static void
1667 1667 zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, void *data)
1668 1668 {
1669 1669 zio_t *gio = pio->io_gang_leader;
1670 1670 zio_t *zio;
1671 1671
1672 1672 ASSERT(BP_IS_GANG(bp) == !!gn);
1673 1673 ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(gio->io_bp));
1674 1674 ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == gio->io_gang_tree);
1675 1675
1676 1676 /*
1677 1677 * If you're a gang header, your data is in gn->gn_gbh.
1678 1678 * If you're a gang member, your data is in 'data' and gn == NULL.
1679 1679 */
1680 1680 zio = zio_gang_issue_func[gio->io_type](pio, bp, gn, data);
1681 1681
1682 1682 if (gn != NULL) {
1683 1683 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC);
1684 1684
1685 1685 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
1686 1686 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
1687 1687 if (BP_IS_HOLE(gbp))
1688 1688 continue;
1689 1689 zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data);
1690 1690 data = (char *)data + BP_GET_PSIZE(gbp);
1691 1691 }
1692 1692 }
1693 1693
1694 1694 if (gn == gio->io_gang_tree)
1695 1695 ASSERT3P((char *)gio->io_data + gio->io_size, ==, data);
1696 1696
1697 1697 if (zio != pio)
1698 1698 zio_nowait(zio);
1699 1699 }
1700 1700
1701 1701 static int
1702 1702 zio_gang_assemble(zio_t *zio)
1703 1703 {
1704 1704 blkptr_t *bp = zio->io_bp;
1705 1705
1706 1706 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == NULL);
1707 1707 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
1708 1708
1709 1709 zio->io_gang_leader = zio;
1710 1710
1711 1711 zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree);
1712 1712
1713 1713 return (ZIO_PIPELINE_CONTINUE);
1714 1714 }
1715 1715
1716 1716 static int
1717 1717 zio_gang_issue(zio_t *zio)
1718 1718 {
1719 1719 blkptr_t *bp = zio->io_bp;
1720 1720
1721 1721 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE))
1722 1722 return (ZIO_PIPELINE_STOP);
1723 1723
1724 1724 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == zio);
1725 1725 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
1726 1726
1727 1727 if (zio->io_child_error[ZIO_CHILD_GANG] == 0)
1728 1728 zio_gang_tree_issue(zio, zio->io_gang_tree, bp, zio->io_data);
1729 1729 else
1730 1730 zio_gang_tree_free(&zio->io_gang_tree);
1731 1731
1732 1732 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1733 1733
1734 1734 return (ZIO_PIPELINE_CONTINUE);
1735 1735 }
1736 1736
1737 1737 static void
1738 1738 zio_write_gang_member_ready(zio_t *zio)
1739 1739 {
1740 1740 zio_t *pio = zio_unique_parent(zio);
1741 1741 zio_t *gio = zio->io_gang_leader;
1742 1742 dva_t *cdva = zio->io_bp->blk_dva;
1743 1743 dva_t *pdva = pio->io_bp->blk_dva;
1744 1744 uint64_t asize;
1745 1745
1746 1746 if (BP_IS_HOLE(zio->io_bp))
1747 1747 return;
1748 1748
1749 1749 ASSERT(BP_IS_HOLE(&zio->io_bp_orig));
1750 1750
1751 1751 ASSERT(zio->io_child_type == ZIO_CHILD_GANG);
1752 1752 ASSERT3U(zio->io_prop.zp_copies, ==, gio->io_prop.zp_copies);
1753 1753 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(zio->io_bp));
1754 1754 ASSERT3U(pio->io_prop.zp_copies, <=, BP_GET_NDVAS(pio->io_bp));
1755 1755 ASSERT3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp));
1756 1756
1757 1757 mutex_enter(&pio->io_lock);
1758 1758 for (int d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) {
1759 1759 ASSERT(DVA_GET_GANG(&pdva[d]));
1760 1760 asize = DVA_GET_ASIZE(&pdva[d]);
1761 1761 asize += DVA_GET_ASIZE(&cdva[d]);
1762 1762 DVA_SET_ASIZE(&pdva[d], asize);
1763 1763 }
1764 1764 mutex_exit(&pio->io_lock);
1765 1765 }
1766 1766
1767 1767 static int
1768 1768 zio_write_gang_block(zio_t *pio)
1769 1769 {
1770 1770 spa_t *spa = pio->io_spa;
1771 1771 blkptr_t *bp = pio->io_bp;
1772 1772 zio_t *gio = pio->io_gang_leader;
1773 1773 zio_t *zio;
1774 1774 zio_gang_node_t *gn, **gnpp;
1775 1775 zio_gbh_phys_t *gbh;
1776 1776 uint64_t txg = pio->io_txg;
1777 1777 uint64_t resid = pio->io_size;
1778 1778 uint64_t lsize;
1779 1779 int copies = gio->io_prop.zp_copies;
1780 1780 int gbh_copies = MIN(copies + 1, spa_max_replication(spa));
1781 1781 zio_prop_t zp;
1782 1782 int error;
1783 1783
1784 1784 error = metaslab_alloc(spa, spa_normal_class(spa), SPA_GANGBLOCKSIZE,
1785 1785 bp, gbh_copies, txg, pio == gio ? NULL : gio->io_bp,
1786 1786 METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER);
1787 1787 if (error) {
1788 1788 pio->io_error = error;
1789 1789 return (ZIO_PIPELINE_CONTINUE);
1790 1790 }
1791 1791
1792 1792 if (pio == gio) {
1793 1793 gnpp = &gio->io_gang_tree;
1794 1794 } else {
1795 1795 gnpp = pio->io_private;
1796 1796 ASSERT(pio->io_ready == zio_write_gang_member_ready);
1797 1797 }
1798 1798
1799 1799 gn = zio_gang_node_alloc(gnpp);
1800 1800 gbh = gn->gn_gbh;
1801 1801 bzero(gbh, SPA_GANGBLOCKSIZE);
1802 1802
1803 1803 /*
1804 1804 * Create the gang header.
1805 1805 */
1806 1806 zio = zio_rewrite(pio, spa, txg, bp, gbh, SPA_GANGBLOCKSIZE, NULL, NULL,
1807 1807 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
1808 1808
1809 1809 /*
1810 1810 * Create and nowait the gang children.
1811 1811 */
1812 1812 for (int g = 0; resid != 0; resid -= lsize, g++) {
1813 1813 lsize = P2ROUNDUP(resid / (SPA_GBH_NBLKPTRS - g),
1814 1814 SPA_MINBLOCKSIZE);
1815 1815 ASSERT(lsize >= SPA_MINBLOCKSIZE && lsize <= resid);
1816 1816
1817 1817 zp.zp_checksum = gio->io_prop.zp_checksum;
1818 1818 zp.zp_compress = ZIO_COMPRESS_OFF;
1819 1819 zp.zp_type = DMU_OT_NONE;
1820 1820 zp.zp_level = 0;
1821 1821 zp.zp_copies = gio->io_prop.zp_copies;
1822 1822 zp.zp_dedup = B_FALSE;
1823 1823 zp.zp_dedup_verify = B_FALSE;
1824 1824 zp.zp_nopwrite = B_FALSE;
1825 1825
1826 1826 zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g],
1827 1827 (char *)pio->io_data + (pio->io_size - resid), lsize, &zp,
1828 1828 zio_write_gang_member_ready, NULL, NULL, &gn->gn_child[g],
1829 1829 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
1830 1830 &pio->io_bookmark));
1831 1831 }
1832 1832
1833 1833 /*
1834 1834 * Set pio's pipeline to just wait for zio to finish.
1835 1835 */
1836 1836 pio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1837 1837
1838 1838 zio_nowait(zio);
1839 1839
1840 1840 return (ZIO_PIPELINE_CONTINUE);
1841 1841 }
1842 1842
1843 1843 /*
1844 1844 * The zio_nop_write stage in the pipeline determines if allocating
1845 1845 * a new bp is necessary. By leveraging a cryptographically secure checksum,
1846 1846 * such as SHA256, we can compare the checksums of the new data and the old
1847 1847 * to determine if allocating a new block is required. The nopwrite
1848 1848 * feature can handle writes in either syncing or open context (i.e. zil
1849 1849 * writes) and as a result is mutually exclusive with dedup.
1850 1850 */
1851 1851 static int
1852 1852 zio_nop_write(zio_t *zio)
1853 1853 {
1854 1854 blkptr_t *bp = zio->io_bp;
1855 1855 blkptr_t *bp_orig = &zio->io_bp_orig;
1856 1856 zio_prop_t *zp = &zio->io_prop;
1857 1857
1858 1858 ASSERT(BP_GET_LEVEL(bp) == 0);
1859 1859 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1860 1860 ASSERT(zp->zp_nopwrite);
1861 1861 ASSERT(!zp->zp_dedup);
1862 1862 ASSERT(zio->io_bp_override == NULL);
1863 1863 ASSERT(IO_IS_ALLOCATING(zio));
1864 1864
1865 1865 /*
1866 1866 * Check to see if the original bp and the new bp have matching
1867 1867 * characteristics (i.e. same checksum, compression algorithms, etc).
1868 1868 * If they don't then just continue with the pipeline which will
1869 1869 * allocate a new bp.
1870 1870 */
1871 1871 if (BP_IS_HOLE(bp_orig) ||
1872 1872 !zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_dedup ||
1873 1873 BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) ||
1874 1874 BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) ||
1875 1875 BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) ||
1876 1876 zp->zp_copies != BP_GET_NDVAS(bp_orig))
1877 1877 return (ZIO_PIPELINE_CONTINUE);
1878 1878
1879 1879 /*
1880 1880 * If the checksums match then reset the pipeline so that we
1881 1881 * avoid allocating a new bp and issuing any I/O.
1882 1882 */
1883 1883 if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) {
1884 1884 ASSERT(zio_checksum_table[zp->zp_checksum].ci_dedup);
1885 1885 ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig));
1886 1886 ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig));
1887 1887 ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF);
1888 1888 ASSERT(bcmp(&bp->blk_prop, &bp_orig->blk_prop,
1889 1889 sizeof (uint64_t)) == 0);
1890 1890
1891 1891 *bp = *bp_orig;
1892 1892 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1893 1893 zio->io_flags |= ZIO_FLAG_NOPWRITE;
1894 1894 }
1895 1895
1896 1896 return (ZIO_PIPELINE_CONTINUE);
1897 1897 }
1898 1898
1899 1899 /*
1900 1900 * ==========================================================================
1901 1901 * Dedup
1902 1902 * ==========================================================================
1903 1903 */
1904 1904 static void
1905 1905 zio_ddt_child_read_done(zio_t *zio)
1906 1906 {
1907 1907 blkptr_t *bp = zio->io_bp;
1908 1908 ddt_entry_t *dde = zio->io_private;
1909 1909 ddt_phys_t *ddp;
1910 1910 zio_t *pio = zio_unique_parent(zio);
1911 1911
1912 1912 mutex_enter(&pio->io_lock);
1913 1913 ddp = ddt_phys_select(dde, bp);
1914 1914 if (zio->io_error == 0)
1915 1915 ddt_phys_clear(ddp); /* this ddp doesn't need repair */
1916 1916 if (zio->io_error == 0 && dde->dde_repair_data == NULL)
1917 1917 dde->dde_repair_data = zio->io_data;
1918 1918 else
1919 1919 zio_buf_free(zio->io_data, zio->io_size);
1920 1920 mutex_exit(&pio->io_lock);
1921 1921 }
1922 1922
1923 1923 static int
1924 1924 zio_ddt_read_start(zio_t *zio)
1925 1925 {
1926 1926 blkptr_t *bp = zio->io_bp;
1927 1927
1928 1928 ASSERT(BP_GET_DEDUP(bp));
1929 1929 ASSERT(BP_GET_PSIZE(bp) == zio->io_size);
1930 1930 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1931 1931
1932 1932 if (zio->io_child_error[ZIO_CHILD_DDT]) {
1933 1933 ddt_t *ddt = ddt_select(zio->io_spa, bp);
1934 1934 ddt_entry_t *dde = ddt_repair_start(ddt, bp);
1935 1935 ddt_phys_t *ddp = dde->dde_phys;
1936 1936 ddt_phys_t *ddp_self = ddt_phys_select(dde, bp);
1937 1937 blkptr_t blk;
1938 1938
1939 1939 ASSERT(zio->io_vsd == NULL);
1940 1940 zio->io_vsd = dde;
1941 1941
1942 1942 if (ddp_self == NULL)
1943 1943 return (ZIO_PIPELINE_CONTINUE);
1944 1944
1945 1945 for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
1946 1946 if (ddp->ddp_phys_birth == 0 || ddp == ddp_self)
1947 1947 continue;
1948 1948 ddt_bp_create(ddt->ddt_checksum, &dde->dde_key, ddp,
1949 1949 &blk);
1950 1950 zio_nowait(zio_read(zio, zio->io_spa, &blk,
1951 1951 zio_buf_alloc(zio->io_size), zio->io_size,
1952 1952 zio_ddt_child_read_done, dde, zio->io_priority,
1953 1953 ZIO_DDT_CHILD_FLAGS(zio) | ZIO_FLAG_DONT_PROPAGATE,
1954 1954 &zio->io_bookmark));
1955 1955 }
1956 1956 return (ZIO_PIPELINE_CONTINUE);
1957 1957 }
1958 1958
1959 1959 zio_nowait(zio_read(zio, zio->io_spa, bp,
1960 1960 zio->io_data, zio->io_size, NULL, NULL, zio->io_priority,
1961 1961 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark));
1962 1962
1963 1963 return (ZIO_PIPELINE_CONTINUE);
1964 1964 }
1965 1965
1966 1966 static int
1967 1967 zio_ddt_read_done(zio_t *zio)
1968 1968 {
1969 1969 blkptr_t *bp = zio->io_bp;
1970 1970
1971 1971 if (zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE))
1972 1972 return (ZIO_PIPELINE_STOP);
1973 1973
1974 1974 ASSERT(BP_GET_DEDUP(bp));
1975 1975 ASSERT(BP_GET_PSIZE(bp) == zio->io_size);
1976 1976 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1977 1977
1978 1978 if (zio->io_child_error[ZIO_CHILD_DDT]) {
1979 1979 ddt_t *ddt = ddt_select(zio->io_spa, bp);
1980 1980 ddt_entry_t *dde = zio->io_vsd;
1981 1981 if (ddt == NULL) {
1982 1982 ASSERT(spa_load_state(zio->io_spa) != SPA_LOAD_NONE);
1983 1983 return (ZIO_PIPELINE_CONTINUE);
1984 1984 }
1985 1985 if (dde == NULL) {
1986 1986 zio->io_stage = ZIO_STAGE_DDT_READ_START >> 1;
1987 1987 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE);
1988 1988 return (ZIO_PIPELINE_STOP);
1989 1989 }
1990 1990 if (dde->dde_repair_data != NULL) {
1991 1991 bcopy(dde->dde_repair_data, zio->io_data, zio->io_size);
1992 1992 zio->io_child_error[ZIO_CHILD_DDT] = 0;
1993 1993 }
1994 1994 ddt_repair_done(ddt, dde);
1995 1995 zio->io_vsd = NULL;
1996 1996 }
1997 1997
1998 1998 ASSERT(zio->io_vsd == NULL);
1999 1999
2000 2000 return (ZIO_PIPELINE_CONTINUE);
2001 2001 }
2002 2002
2003 2003 static boolean_t
2004 2004 zio_ddt_collision(zio_t *zio, ddt_t *ddt, ddt_entry_t *dde)
2005 2005 {
2006 2006 spa_t *spa = zio->io_spa;
2007 2007
2008 2008 /*
2009 2009 * Note: we compare the original data, not the transformed data,
2010 2010 * because when zio->io_bp is an override bp, we will not have
2011 2011 * pushed the I/O transforms. That's an important optimization
2012 2012 * because otherwise we'd compress/encrypt all dmu_sync() data twice.
2013 2013 */
2014 2014 for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
2015 2015 zio_t *lio = dde->dde_lead_zio[p];
2016 2016
2017 2017 if (lio != NULL) {
2018 2018 return (lio->io_orig_size != zio->io_orig_size ||
2019 2019 bcmp(zio->io_orig_data, lio->io_orig_data,
2020 2020 zio->io_orig_size) != 0);
2021 2021 }
2022 2022 }
2023 2023
2024 2024 for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
2025 2025 ddt_phys_t *ddp = &dde->dde_phys[p];
2026 2026
2027 2027 if (ddp->ddp_phys_birth != 0) {
2028 2028 arc_buf_t *abuf = NULL;
2029 2029 uint32_t aflags = ARC_WAIT;
2030 2030 blkptr_t blk = *zio->io_bp;
2031 2031 int error;
2032 2032
2033 2033 ddt_bp_fill(ddp, &blk, ddp->ddp_phys_birth);
2034 2034
2035 2035 ddt_exit(ddt);
2036 2036
2037 2037 error = arc_read(NULL, spa, &blk,
2038 2038 arc_getbuf_func, &abuf, ZIO_PRIORITY_SYNC_READ,
2039 2039 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE,
2040 2040 &aflags, &zio->io_bookmark);
2041 2041
2042 2042 if (error == 0) {
2043 2043 if (arc_buf_size(abuf) != zio->io_orig_size ||
2044 2044 bcmp(abuf->b_data, zio->io_orig_data,
2045 2045 zio->io_orig_size) != 0)
2046 2046 error = SET_ERROR(EEXIST);
2047 2047 VERIFY(arc_buf_remove_ref(abuf, &abuf));
2048 2048 }
2049 2049
2050 2050 ddt_enter(ddt);
2051 2051 return (error != 0);
2052 2052 }
2053 2053 }
2054 2054
2055 2055 return (B_FALSE);
2056 2056 }
2057 2057
2058 2058 static void
2059 2059 zio_ddt_child_write_ready(zio_t *zio)
2060 2060 {
2061 2061 int p = zio->io_prop.zp_copies;
2062 2062 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp);
2063 2063 ddt_entry_t *dde = zio->io_private;
2064 2064 ddt_phys_t *ddp = &dde->dde_phys[p];
2065 2065 zio_t *pio;
2066 2066
2067 2067 if (zio->io_error)
2068 2068 return;
2069 2069
2070 2070 ddt_enter(ddt);
2071 2071
2072 2072 ASSERT(dde->dde_lead_zio[p] == zio);
2073 2073
2074 2074 ddt_phys_fill(ddp, zio->io_bp);
2075 2075
2076 2076 while ((pio = zio_walk_parents(zio)) != NULL)
2077 2077 ddt_bp_fill(ddp, pio->io_bp, zio->io_txg);
2078 2078
2079 2079 ddt_exit(ddt);
2080 2080 }
2081 2081
2082 2082 static void
2083 2083 zio_ddt_child_write_done(zio_t *zio)
2084 2084 {
2085 2085 int p = zio->io_prop.zp_copies;
2086 2086 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp);
2087 2087 ddt_entry_t *dde = zio->io_private;
2088 2088 ddt_phys_t *ddp = &dde->dde_phys[p];
2089 2089
2090 2090 ddt_enter(ddt);
2091 2091
2092 2092 ASSERT(ddp->ddp_refcnt == 0);
2093 2093 ASSERT(dde->dde_lead_zio[p] == zio);
2094 2094 dde->dde_lead_zio[p] = NULL;
2095 2095
2096 2096 if (zio->io_error == 0) {
2097 2097 while (zio_walk_parents(zio) != NULL)
2098 2098 ddt_phys_addref(ddp);
2099 2099 } else {
2100 2100 ddt_phys_clear(ddp);
2101 2101 }
2102 2102
2103 2103 ddt_exit(ddt);
2104 2104 }
2105 2105
2106 2106 static void
2107 2107 zio_ddt_ditto_write_done(zio_t *zio)
2108 2108 {
2109 2109 int p = DDT_PHYS_DITTO;
2110 2110 zio_prop_t *zp = &zio->io_prop;
2111 2111 blkptr_t *bp = zio->io_bp;
2112 2112 ddt_t *ddt = ddt_select(zio->io_spa, bp);
2113 2113 ddt_entry_t *dde = zio->io_private;
2114 2114 ddt_phys_t *ddp = &dde->dde_phys[p];
2115 2115 ddt_key_t *ddk = &dde->dde_key;
2116 2116
2117 2117 ddt_enter(ddt);
2118 2118
2119 2119 ASSERT(ddp->ddp_refcnt == 0);
2120 2120 ASSERT(dde->dde_lead_zio[p] == zio);
2121 2121 dde->dde_lead_zio[p] = NULL;
2122 2122
2123 2123 if (zio->io_error == 0) {
2124 2124 ASSERT(ZIO_CHECKSUM_EQUAL(bp->blk_cksum, ddk->ddk_cksum));
2125 2125 ASSERT(zp->zp_copies < SPA_DVAS_PER_BP);
2126 2126 ASSERT(zp->zp_copies == BP_GET_NDVAS(bp) - BP_IS_GANG(bp));
2127 2127 if (ddp->ddp_phys_birth != 0)
2128 2128 ddt_phys_free(ddt, ddk, ddp, zio->io_txg);
2129 2129 ddt_phys_fill(ddp, bp);
2130 2130 }
2131 2131
2132 2132 ddt_exit(ddt);
2133 2133 }
2134 2134
2135 2135 static int
2136 2136 zio_ddt_write(zio_t *zio)
2137 2137 {
2138 2138 spa_t *spa = zio->io_spa;
2139 2139 blkptr_t *bp = zio->io_bp;
2140 2140 uint64_t txg = zio->io_txg;
2141 2141 zio_prop_t *zp = &zio->io_prop;
2142 2142 int p = zp->zp_copies;
2143 2143 int ditto_copies;
2144 2144 zio_t *cio = NULL;
2145 2145 zio_t *dio = NULL;
2146 2146 ddt_t *ddt = ddt_select(spa, bp);
2147 2147 ddt_entry_t *dde;
2148 2148 ddt_phys_t *ddp;
2149 2149
2150 2150 ASSERT(BP_GET_DEDUP(bp));
2151 2151 ASSERT(BP_GET_CHECKSUM(bp) == zp->zp_checksum);
2152 2152 ASSERT(BP_IS_HOLE(bp) || zio->io_bp_override);
2153 2153
2154 2154 ddt_enter(ddt);
2155 2155 dde = ddt_lookup(ddt, bp, B_TRUE);
2156 2156 ddp = &dde->dde_phys[p];
2157 2157
2158 2158 if (zp->zp_dedup_verify && zio_ddt_collision(zio, ddt, dde)) {
2159 2159 /*
2160 2160 * If we're using a weak checksum, upgrade to a strong checksum
2161 2161 * and try again. If we're already using a strong checksum,
2162 2162 * we can't resolve it, so just convert to an ordinary write.
2163 2163 * (And automatically e-mail a paper to Nature?)
2164 2164 */
2165 2165 if (!zio_checksum_table[zp->zp_checksum].ci_dedup) {
2166 2166 zp->zp_checksum = spa_dedup_checksum(spa);
2167 2167 zio_pop_transforms(zio);
2168 2168 zio->io_stage = ZIO_STAGE_OPEN;
2169 2169 BP_ZERO(bp);
2170 2170 } else {
2171 2171 zp->zp_dedup = B_FALSE;
2172 2172 }
2173 2173 zio->io_pipeline = ZIO_WRITE_PIPELINE;
2174 2174 ddt_exit(ddt);
2175 2175 return (ZIO_PIPELINE_CONTINUE);
2176 2176 }
2177 2177
2178 2178 ditto_copies = ddt_ditto_copies_needed(ddt, dde, ddp);
2179 2179 ASSERT(ditto_copies < SPA_DVAS_PER_BP);
2180 2180
2181 2181 if (ditto_copies > ddt_ditto_copies_present(dde) &&
2182 2182 dde->dde_lead_zio[DDT_PHYS_DITTO] == NULL) {
2183 2183 zio_prop_t czp = *zp;
2184 2184
2185 2185 czp.zp_copies = ditto_copies;
2186 2186
2187 2187 /*
2188 2188 * If we arrived here with an override bp, we won't have run
2189 2189 * the transform stack, so we won't have the data we need to
2190 2190 * generate a child i/o. So, toss the override bp and restart.
2191 2191 * This is safe, because using the override bp is just an
2192 2192 * optimization; and it's rare, so the cost doesn't matter.
2193 2193 */
2194 2194 if (zio->io_bp_override) {
2195 2195 zio_pop_transforms(zio);
2196 2196 zio->io_stage = ZIO_STAGE_OPEN;
2197 2197 zio->io_pipeline = ZIO_WRITE_PIPELINE;
2198 2198 zio->io_bp_override = NULL;
2199 2199 BP_ZERO(bp);
2200 2200 ddt_exit(ddt);
2201 2201 return (ZIO_PIPELINE_CONTINUE);
2202 2202 }
2203 2203
2204 2204 dio = zio_write(zio, spa, txg, bp, zio->io_orig_data,
2205 2205 zio->io_orig_size, &czp, NULL, NULL,
2206 2206 zio_ddt_ditto_write_done, dde, zio->io_priority,
2207 2207 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
2208 2208
2209 2209 zio_push_transform(dio, zio->io_data, zio->io_size, 0, NULL);
2210 2210 dde->dde_lead_zio[DDT_PHYS_DITTO] = dio;
2211 2211 }
2212 2212
2213 2213 if (ddp->ddp_phys_birth != 0 || dde->dde_lead_zio[p] != NULL) {
2214 2214 if (ddp->ddp_phys_birth != 0)
2215 2215 ddt_bp_fill(ddp, bp, txg);
2216 2216 if (dde->dde_lead_zio[p] != NULL)
2217 2217 zio_add_child(zio, dde->dde_lead_zio[p]);
2218 2218 else
2219 2219 ddt_phys_addref(ddp);
2220 2220 } else if (zio->io_bp_override) {
2221 2221 ASSERT(bp->blk_birth == txg);
2222 2222 ASSERT(BP_EQUAL(bp, zio->io_bp_override));
2223 2223 ddt_phys_fill(ddp, bp);
2224 2224 ddt_phys_addref(ddp);
2225 2225 } else {
2226 2226 cio = zio_write(zio, spa, txg, bp, zio->io_orig_data,
2227 2227 zio->io_orig_size, zp, zio_ddt_child_write_ready, NULL,
2228 2228 zio_ddt_child_write_done, dde, zio->io_priority,
2229 2229 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
2230 2230
2231 2231 zio_push_transform(cio, zio->io_data, zio->io_size, 0, NULL);
2232 2232 dde->dde_lead_zio[p] = cio;
2233 2233 }
2234 2234
2235 2235 ddt_exit(ddt);
2236 2236
2237 2237 if (cio)
2238 2238 zio_nowait(cio);
2239 2239 if (dio)
2240 2240 zio_nowait(dio);
2241 2241
2242 2242 return (ZIO_PIPELINE_CONTINUE);
2243 2243 }
2244 2244
2245 2245 ddt_entry_t *freedde; /* for debugging */
2246 2246
2247 2247 static int
2248 2248 zio_ddt_free(zio_t *zio)
2249 2249 {
2250 2250 spa_t *spa = zio->io_spa;
2251 2251 blkptr_t *bp = zio->io_bp;
2252 2252 ddt_t *ddt = ddt_select(spa, bp);
2253 2253 ddt_entry_t *dde;
2254 2254 ddt_phys_t *ddp;
2255 2255
2256 2256 ASSERT(BP_GET_DEDUP(bp));
2257 2257 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2258 2258
2259 2259 ddt_enter(ddt);
2260 2260 freedde = dde = ddt_lookup(ddt, bp, B_TRUE);
2261 2261 ddp = ddt_phys_select(dde, bp);
2262 2262 ddt_phys_decref(ddp);
2263 2263 ddt_exit(ddt);
2264 2264
2265 2265 return (ZIO_PIPELINE_CONTINUE);
2266 2266 }
2267 2267
2268 2268 /*
2269 2269 * ==========================================================================
2270 2270 * Allocate and free blocks
2271 2271 * ==========================================================================
2272 2272 */
2273 2273 static int
2274 2274 zio_dva_allocate(zio_t *zio)
2275 2275 {
2276 2276 spa_t *spa = zio->io_spa;
2277 2277 metaslab_class_t *mc = spa_normal_class(spa);
2278 2278 blkptr_t *bp = zio->io_bp;
2279 2279 int error;
2280 2280 int flags = 0;
2281 2281
2282 2282 if (zio->io_gang_leader == NULL) {
2283 2283 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
2284 2284 zio->io_gang_leader = zio;
2285 2285 }
2286 2286
2287 2287 ASSERT(BP_IS_HOLE(bp));
2288 2288 ASSERT0(BP_GET_NDVAS(bp));
2289 2289 ASSERT3U(zio->io_prop.zp_copies, >, 0);
2290 2290 ASSERT3U(zio->io_prop.zp_copies, <=, spa_max_replication(spa));
2291 2291 ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp));
2292 2292
2293 2293 /*
2294 2294 * The dump device does not support gang blocks so allocation on
2295 2295 * behalf of the dump device (i.e. ZIO_FLAG_NODATA) must avoid
2296 2296 * the "fast" gang feature.
2297 2297 */
2298 2298 flags |= (zio->io_flags & ZIO_FLAG_NODATA) ? METASLAB_GANG_AVOID : 0;
2299 2299 flags |= (zio->io_flags & ZIO_FLAG_GANG_CHILD) ?
2300 2300 METASLAB_GANG_CHILD : 0;
2301 2301 error = metaslab_alloc(spa, mc, zio->io_size, bp,
2302 2302 zio->io_prop.zp_copies, zio->io_txg, NULL, flags);
2303 2303
2304 2304 if (error) {
2305 2305 spa_dbgmsg(spa, "%s: metaslab allocation failure: zio %p, "
2306 2306 "size %llu, error %d", spa_name(spa), zio, zio->io_size,
2307 2307 error);
2308 2308 if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE)
2309 2309 return (zio_write_gang_block(zio));
2310 2310 zio->io_error = error;
2311 2311 }
2312 2312
2313 2313 return (ZIO_PIPELINE_CONTINUE);
2314 2314 }
2315 2315
2316 2316 static int
2317 2317 zio_dva_free(zio_t *zio)
2318 2318 {
2319 2319 metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE);
2320 2320
2321 2321 return (ZIO_PIPELINE_CONTINUE);
2322 2322 }
2323 2323
2324 2324 static int
2325 2325 zio_dva_claim(zio_t *zio)
2326 2326 {
2327 2327 int error;
2328 2328
2329 2329 error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg);
2330 2330 if (error)
2331 2331 zio->io_error = error;
2332 2332
2333 2333 return (ZIO_PIPELINE_CONTINUE);
2334 2334 }
2335 2335
2336 2336 /*
2337 2337 * Undo an allocation. This is used by zio_done() when an I/O fails
2338 2338 * and we want to give back the block we just allocated.
2339 2339 * This handles both normal blocks and gang blocks.
2340 2340 */
2341 2341 static void
2342 2342 zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp)
2343 2343 {
2344 2344 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp));
2345 2345 ASSERT(zio->io_bp_override == NULL);
2346 2346
2347 2347 if (!BP_IS_HOLE(bp))
2348 2348 metaslab_free(zio->io_spa, bp, bp->blk_birth, B_TRUE);
2349 2349
2350 2350 if (gn != NULL) {
2351 2351 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
2352 2352 zio_dva_unallocate(zio, gn->gn_child[g],
2353 2353 &gn->gn_gbh->zg_blkptr[g]);
2354 2354 }
2355 2355 }
2356 2356 }
2357 2357
2358 2358 /*
2359 2359 * Try to allocate an intent log block. Return 0 on success, errno on failure.
2360 2360 */
2361 2361 int
2362 2362 zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp, blkptr_t *old_bp,
2363 2363 uint64_t size, boolean_t use_slog)
2364 2364 {
2365 2365 int error = 1;
2366 2366
2367 2367 ASSERT(txg > spa_syncing_txg(spa));
2368 2368
2369 2369 /*
2370 2370 * ZIL blocks are always contiguous (i.e. not gang blocks) so we
2371 2371 * set the METASLAB_GANG_AVOID flag so that they don't "fast gang"
2372 2372 * when allocating them.
2373 2373 */
2374 2374 if (use_slog) {
2375 2375 error = metaslab_alloc(spa, spa_log_class(spa), size,
2376 2376 new_bp, 1, txg, old_bp,
2377 2377 METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID);
2378 2378 }
2379 2379
2380 2380 if (error) {
2381 2381 error = metaslab_alloc(spa, spa_normal_class(spa), size,
2382 2382 new_bp, 1, txg, old_bp,
2383 2383 METASLAB_HINTBP_AVOID);
2384 2384 }
2385 2385
2386 2386 if (error == 0) {
2387 2387 BP_SET_LSIZE(new_bp, size);
2388 2388 BP_SET_PSIZE(new_bp, size);
2389 2389 BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF);
2390 2390 BP_SET_CHECKSUM(new_bp,
2391 2391 spa_version(spa) >= SPA_VERSION_SLIM_ZIL
2392 2392 ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG);
2393 2393 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG);
2394 2394 BP_SET_LEVEL(new_bp, 0);
2395 2395 BP_SET_DEDUP(new_bp, 0);
2396 2396 BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER);
2397 2397 }
2398 2398
2399 2399 return (error);
2400 2400 }
2401 2401
2402 2402 /*
2403 2403 * Free an intent log block.
2404 2404 */
2405 2405 void
2406 2406 zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp)
2407 2407 {
2408 2408 ASSERT(BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG);
2409 2409 ASSERT(!BP_IS_GANG(bp));
2410 2410
2411 2411 zio_free(spa, txg, bp);
2412 2412 }
2413 2413
2414 2414 /*
2415 2415 * ==========================================================================
2416 2416 * Read and write to physical devices
2417 2417 * ==========================================================================
2418 2418 */
2419 2419 static int
2420 2420 zio_vdev_io_start(zio_t *zio)
2421 2421 {
2422 2422 vdev_t *vd = zio->io_vd;
2423 2423 uint64_t align;
2424 2424 spa_t *spa = zio->io_spa;
2425 2425
2426 2426 ASSERT(zio->io_error == 0);
2427 2427 ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0);
2428 2428
2429 2429 if (vd == NULL) {
2430 2430 if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
2431 2431 spa_config_enter(spa, SCL_ZIO, zio, RW_READER);
2432 2432
2433 2433 /*
2434 2434 * The mirror_ops handle multiple DVAs in a single BP.
2435 2435 */
2436 2436 return (vdev_mirror_ops.vdev_op_io_start(zio));
2437 2437 }
2438 2438
2439 2439 /*
2440 2440 * We keep track of time-sensitive I/Os so that the scan thread
2441 2441 * can quickly react to certain workloads. In particular, we care
2442 2442 * about non-scrubbing, top-level reads and writes with the following
2443 2443 * characteristics:
2444 2444 * - synchronous writes of user data to non-slog devices
2445 2445 * - any reads of user data
2446 2446 * When these conditions are met, adjust the timestamp of spa_last_io
2447 2447 * which allows the scan thread to adjust its workload accordingly.
2448 2448 */
2449 2449 if (!(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && zio->io_bp != NULL &&
2450 2450 vd == vd->vdev_top && !vd->vdev_islog &&
2451 2451 zio->io_bookmark.zb_objset != DMU_META_OBJSET &&
2452 2452 zio->io_txg != spa_syncing_txg(spa)) {
2453 2453 uint64_t old = spa->spa_last_io;
2454 2454 uint64_t new = ddi_get_lbolt64();
2455 2455 if (old != new)
2456 2456 (void) atomic_cas_64(&spa->spa_last_io, old, new);
2457 2457 }
2458 2458
2459 2459 align = 1ULL << vd->vdev_top->vdev_ashift;
2460 2460
2461 2461 if (P2PHASE(zio->io_size, align) != 0) {
2462 2462 uint64_t asize = P2ROUNDUP(zio->io_size, align);
2463 2463 char *abuf = zio_buf_alloc(asize);
2464 2464 ASSERT(vd == vd->vdev_top);
2465 2465 if (zio->io_type == ZIO_TYPE_WRITE) {
2466 2466 bcopy(zio->io_data, abuf, zio->io_size);
2467 2467 bzero(abuf + zio->io_size, asize - zio->io_size);
2468 2468 }
2469 2469 zio_push_transform(zio, abuf, asize, asize, zio_subblock);
2470 2470 }
2471 2471
2472 2472 ASSERT(P2PHASE(zio->io_offset, align) == 0);
2473 2473 ASSERT(P2PHASE(zio->io_size, align) == 0);
2474 2474 VERIFY(zio->io_type != ZIO_TYPE_WRITE || spa_writeable(spa));
2475 2475
2476 2476 /*
2477 2477 * If this is a repair I/O, and there's no self-healing involved --
2478 2478 * that is, we're just resilvering what we expect to resilver --
2479 2479 * then don't do the I/O unless zio's txg is actually in vd's DTL.
2480 2480 * This prevents spurious resilvering with nested replication.
2481 2481 * For example, given a mirror of mirrors, (A+B)+(C+D), if only
2482 2482 * A is out of date, we'll read from C+D, then use the data to
2483 2483 * resilver A+B -- but we don't actually want to resilver B, just A.
2484 2484 * The top-level mirror has no way to know this, so instead we just
2485 2485 * discard unnecessary repairs as we work our way down the vdev tree.
2486 2486 * The same logic applies to any form of nested replication:
2487 2487 * ditto + mirror, RAID-Z + replacing, etc. This covers them all.
2488 2488 */
2489 2489 if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) &&
2490 2490 !(zio->io_flags & ZIO_FLAG_SELF_HEAL) &&
2491 2491 zio->io_txg != 0 && /* not a delegated i/o */
2492 2492 !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) {
2493 2493 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
2494 2494 zio_vdev_io_bypass(zio);
2495 2495 return (ZIO_PIPELINE_CONTINUE);
2496 2496 }
2497 2497
2498 2498 if (vd->vdev_ops->vdev_op_leaf &&
2499 2499 (zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE)) {
2500 2500
2501 2501 if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio))
2502 2502 return (ZIO_PIPELINE_CONTINUE);
2503 2503
2504 2504 if ((zio = vdev_queue_io(zio)) == NULL)
2505 2505 return (ZIO_PIPELINE_STOP);
2506 2506
2507 2507 if (!vdev_accessible(vd, zio)) {
2508 2508 zio->io_error = SET_ERROR(ENXIO);
2509 2509 zio_interrupt(zio);
2510 2510 return (ZIO_PIPELINE_STOP);
2511 2511 }
2512 2512 }
2513 2513
2514 2514 return (vd->vdev_ops->vdev_op_io_start(zio));
2515 2515 }
2516 2516
2517 2517 static int
2518 2518 zio_vdev_io_done(zio_t *zio)
2519 2519 {
2520 2520 vdev_t *vd = zio->io_vd;
2521 2521 vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops;
2522 2522 boolean_t unexpected_error = B_FALSE;
2523 2523
2524 2524 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
2525 2525 return (ZIO_PIPELINE_STOP);
2526 2526
2527 2527 ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
2528 2528
2529 2529 if (vd != NULL && vd->vdev_ops->vdev_op_leaf) {
2530 2530
2531 2531 vdev_queue_io_done(zio);
2532 2532
2533 2533 if (zio->io_type == ZIO_TYPE_WRITE)
2534 2534 vdev_cache_write(zio);
2535 2535
2536 2536 if (zio_injection_enabled && zio->io_error == 0)
2537 2537 zio->io_error = zio_handle_device_injection(vd,
2538 2538 zio, EIO);
2539 2539
2540 2540 if (zio_injection_enabled && zio->io_error == 0)
2541 2541 zio->io_error = zio_handle_label_injection(zio, EIO);
2542 2542
2543 2543 if (zio->io_error) {
2544 2544 if (!vdev_accessible(vd, zio)) {
2545 2545 zio->io_error = SET_ERROR(ENXIO);
2546 2546 } else {
2547 2547 unexpected_error = B_TRUE;
2548 2548 }
2549 2549 }
2550 2550 }
2551 2551
2552 2552 ops->vdev_op_io_done(zio);
2553 2553
2554 2554 if (unexpected_error)
2555 2555 VERIFY(vdev_probe(vd, zio) == NULL);
2556 2556
2557 2557 return (ZIO_PIPELINE_CONTINUE);
2558 2558 }
2559 2559
2560 2560 /*
2561 2561 * For non-raidz ZIOs, we can just copy aside the bad data read from the
2562 2562 * disk, and use that to finish the checksum ereport later.
2563 2563 */
2564 2564 static void
2565 2565 zio_vsd_default_cksum_finish(zio_cksum_report_t *zcr,
2566 2566 const void *good_buf)
2567 2567 {
2568 2568 /* no processing needed */
2569 2569 zfs_ereport_finish_checksum(zcr, good_buf, zcr->zcr_cbdata, B_FALSE);
2570 2570 }
2571 2571
2572 2572 /*ARGSUSED*/
2573 2573 void
2574 2574 zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr, void *ignored)
2575 2575 {
2576 2576 void *buf = zio_buf_alloc(zio->io_size);
2577 2577
2578 2578 bcopy(zio->io_data, buf, zio->io_size);
2579 2579
2580 2580 zcr->zcr_cbinfo = zio->io_size;
2581 2581 zcr->zcr_cbdata = buf;
2582 2582 zcr->zcr_finish = zio_vsd_default_cksum_finish;
2583 2583 zcr->zcr_free = zio_buf_free;
2584 2584 }
2585 2585
2586 2586 static int
2587 2587 zio_vdev_io_assess(zio_t *zio)
2588 2588 {
2589 2589 vdev_t *vd = zio->io_vd;
2590 2590
2591 2591 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
2592 2592 return (ZIO_PIPELINE_STOP);
2593 2593
2594 2594 if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
2595 2595 spa_config_exit(zio->io_spa, SCL_ZIO, zio);
2596 2596
2597 2597 if (zio->io_vsd != NULL) {
2598 2598 zio->io_vsd_ops->vsd_free(zio);
2599 2599 zio->io_vsd = NULL;
2600 2600 }
2601 2601
2602 2602 if (zio_injection_enabled && zio->io_error == 0)
2603 2603 zio->io_error = zio_handle_fault_injection(zio, EIO);
2604 2604
2605 2605 /*
2606 2606 * If the I/O failed, determine whether we should attempt to retry it.
2607 2607 *
2608 2608 * On retry, we cut in line in the issue queue, since we don't want
2609 2609 * compression/checksumming/etc. work to prevent our (cheap) IO reissue.
2610 2610 */
2611 2611 if (zio->io_error && vd == NULL &&
2612 2612 !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) {
2613 2613 ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */
2614 2614 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */
2615 2615 zio->io_error = 0;
2616 2616 zio->io_flags |= ZIO_FLAG_IO_RETRY |
2617 2617 ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_AGGREGATE;
2618 2618 zio->io_stage = ZIO_STAGE_VDEV_IO_START >> 1;
2619 2619 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE,
2620 2620 zio_requeue_io_start_cut_in_line);
2621 2621 return (ZIO_PIPELINE_STOP);
2622 2622 }
2623 2623
2624 2624 /*
2625 2625 * If we got an error on a leaf device, convert it to ENXIO
2626 2626 * if the device is not accessible at all.
2627 2627 */
2628 2628 if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf &&
2629 2629 !vdev_accessible(vd, zio))
2630 2630 zio->io_error = SET_ERROR(ENXIO);
2631 2631
2632 2632 /*
2633 2633 * If we can't write to an interior vdev (mirror or RAID-Z),
2634 2634 * set vdev_cant_write so that we stop trying to allocate from it.
2635 2635 */
2636 2636 if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE &&
2637 2637 vd != NULL && !vd->vdev_ops->vdev_op_leaf) {
2638 2638 vd->vdev_cant_write = B_TRUE;
2639 2639 }
2640 2640
2641 2641 if (zio->io_error)
2642 2642 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2643 2643
2644 2644 if (vd != NULL && vd->vdev_ops->vdev_op_leaf &&
2645 2645 zio->io_physdone != NULL) {
2646 2646 ASSERT(!(zio->io_flags & ZIO_FLAG_DELEGATED));
2647 2647 ASSERT(zio->io_child_type == ZIO_CHILD_VDEV);
2648 2648 zio->io_physdone(zio->io_logical);
2649 2649 }
2650 2650
2651 2651 return (ZIO_PIPELINE_CONTINUE);
2652 2652 }
2653 2653
2654 2654 void
2655 2655 zio_vdev_io_reissue(zio_t *zio)
2656 2656 {
2657 2657 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START);
2658 2658 ASSERT(zio->io_error == 0);
2659 2659
2660 2660 zio->io_stage >>= 1;
2661 2661 }
2662 2662
2663 2663 void
2664 2664 zio_vdev_io_redone(zio_t *zio)
2665 2665 {
2666 2666 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_DONE);
2667 2667
2668 2668 zio->io_stage >>= 1;
2669 2669 }
2670 2670
2671 2671 void
2672 2672 zio_vdev_io_bypass(zio_t *zio)
2673 2673 {
2674 2674 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START);
2675 2675 ASSERT(zio->io_error == 0);
2676 2676
2677 2677 zio->io_flags |= ZIO_FLAG_IO_BYPASS;
2678 2678 zio->io_stage = ZIO_STAGE_VDEV_IO_ASSESS >> 1;
2679 2679 }
2680 2680
2681 2681 /*
2682 2682 * ==========================================================================
2683 2683 * Generate and verify checksums
2684 2684 * ==========================================================================
2685 2685 */
2686 2686 static int
2687 2687 zio_checksum_generate(zio_t *zio)
2688 2688 {
2689 2689 blkptr_t *bp = zio->io_bp;
2690 2690 enum zio_checksum checksum;
2691 2691
2692 2692 if (bp == NULL) {
2693 2693 /*
2694 2694 * This is zio_write_phys().
2695 2695 * We're either generating a label checksum, or none at all.
2696 2696 */
2697 2697 checksum = zio->io_prop.zp_checksum;
2698 2698
2699 2699 if (checksum == ZIO_CHECKSUM_OFF)
2700 2700 return (ZIO_PIPELINE_CONTINUE);
2701 2701
2702 2702 ASSERT(checksum == ZIO_CHECKSUM_LABEL);
2703 2703 } else {
2704 2704 if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) {
2705 2705 ASSERT(!IO_IS_ALLOCATING(zio));
2706 2706 checksum = ZIO_CHECKSUM_GANG_HEADER;
2707 2707 } else {
2708 2708 checksum = BP_GET_CHECKSUM(bp);
2709 2709 }
2710 2710 }
2711 2711
2712 2712 zio_checksum_compute(zio, checksum, zio->io_data, zio->io_size);
2713 2713
2714 2714 return (ZIO_PIPELINE_CONTINUE);
2715 2715 }
2716 2716
2717 2717 static int
2718 2718 zio_checksum_verify(zio_t *zio)
2719 2719 {
2720 2720 zio_bad_cksum_t info;
2721 2721 blkptr_t *bp = zio->io_bp;
2722 2722 int error;
2723 2723
2724 2724 ASSERT(zio->io_vd != NULL);
2725 2725
2726 2726 if (bp == NULL) {
2727 2727 /*
2728 2728 * This is zio_read_phys().
2729 2729 * We're either verifying a label checksum, or nothing at all.
2730 2730 */
2731 2731 if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF)
2732 2732 return (ZIO_PIPELINE_CONTINUE);
2733 2733
2734 2734 ASSERT(zio->io_prop.zp_checksum == ZIO_CHECKSUM_LABEL);
2735 2735 }
2736 2736
2737 2737 if ((error = zio_checksum_error(zio, &info)) != 0) {
2738 2738 zio->io_error = error;
2739 2739 if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
2740 2740 zfs_ereport_start_checksum(zio->io_spa,
2741 2741 zio->io_vd, zio, zio->io_offset,
2742 2742 zio->io_size, NULL, &info);
2743 2743 }
2744 2744 }
2745 2745
2746 2746 return (ZIO_PIPELINE_CONTINUE);
2747 2747 }
2748 2748
2749 2749 /*
2750 2750 * Called by RAID-Z to ensure we don't compute the checksum twice.
2751 2751 */
2752 2752 void
2753 2753 zio_checksum_verified(zio_t *zio)
2754 2754 {
2755 2755 zio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY;
2756 2756 }
2757 2757
2758 2758 /*
2759 2759 * ==========================================================================
2760 2760 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other.
2761 2761 * An error of 0 indictes success. ENXIO indicates whole-device failure,
2762 2762 * which may be transient (e.g. unplugged) or permament. ECKSUM and EIO
2763 2763 * indicate errors that are specific to one I/O, and most likely permanent.
2764 2764 * Any other error is presumed to be worse because we weren't expecting it.
2765 2765 * ==========================================================================
2766 2766 */
2767 2767 int
2768 2768 zio_worst_error(int e1, int e2)
2769 2769 {
2770 2770 static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO };
2771 2771 int r1, r2;
2772 2772
2773 2773 for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++)
2774 2774 if (e1 == zio_error_rank[r1])
2775 2775 break;
2776 2776
2777 2777 for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++)
2778 2778 if (e2 == zio_error_rank[r2])
2779 2779 break;
2780 2780
2781 2781 return (r1 > r2 ? e1 : e2);
2782 2782 }
2783 2783
2784 2784 /*
2785 2785 * ==========================================================================
2786 2786 * I/O completion
2787 2787 * ==========================================================================
2788 2788 */
2789 2789 static int
2790 2790 zio_ready(zio_t *zio)
2791 2791 {
2792 2792 blkptr_t *bp = zio->io_bp;
2793 2793 zio_t *pio, *pio_next;
2794 2794
2795 2795 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
2796 2796 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_READY))
2797 2797 return (ZIO_PIPELINE_STOP);
2798 2798
2799 2799 if (zio->io_ready) {
2800 2800 ASSERT(IO_IS_ALLOCATING(zio));
2801 2801 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp) ||
2802 2802 (zio->io_flags & ZIO_FLAG_NOPWRITE));
2803 2803 ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0);
2804 2804
2805 2805 zio->io_ready(zio);
2806 2806 }
2807 2807
2808 2808 if (bp != NULL && bp != &zio->io_bp_copy)
2809 2809 zio->io_bp_copy = *bp;
2810 2810
2811 2811 if (zio->io_error)
2812 2812 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2813 2813
2814 2814 mutex_enter(&zio->io_lock);
2815 2815 zio->io_state[ZIO_WAIT_READY] = 1;
2816 2816 pio = zio_walk_parents(zio);
2817 2817 mutex_exit(&zio->io_lock);
2818 2818
2819 2819 /*
2820 2820 * As we notify zio's parents, new parents could be added.
2821 2821 * New parents go to the head of zio's io_parent_list, however,
2822 2822 * so we will (correctly) not notify them. The remainder of zio's
2823 2823 * io_parent_list, from 'pio_next' onward, cannot change because
2824 2824 * all parents must wait for us to be done before they can be done.
2825 2825 */
2826 2826 for (; pio != NULL; pio = pio_next) {
2827 2827 pio_next = zio_walk_parents(zio);
2828 2828 zio_notify_parent(pio, zio, ZIO_WAIT_READY);
2829 2829 }
2830 2830
2831 2831 if (zio->io_flags & ZIO_FLAG_NODATA) {
2832 2832 if (BP_IS_GANG(bp)) {
2833 2833 zio->io_flags &= ~ZIO_FLAG_NODATA;
2834 2834 } else {
2835 2835 ASSERT((uintptr_t)zio->io_data < SPA_MAXBLOCKSIZE);
2836 2836 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
2837 2837 }
2838 2838 }
2839 2839
2840 2840 if (zio_injection_enabled &&
2841 2841 zio->io_spa->spa_syncing_txg == zio->io_txg)
2842 2842 zio_handle_ignored_writes(zio);
2843 2843
2844 2844 return (ZIO_PIPELINE_CONTINUE);
2845 2845 }
2846 2846
2847 2847 static int
2848 2848 zio_done(zio_t *zio)
2849 2849 {
2850 2850 spa_t *spa = zio->io_spa;
2851 2851 zio_t *lio = zio->io_logical;
2852 2852 blkptr_t *bp = zio->io_bp;
2853 2853 vdev_t *vd = zio->io_vd;
2854 2854 uint64_t psize = zio->io_size;
2855 2855 zio_t *pio, *pio_next;
2856 2856
2857 2857 /*
2858 2858 * If our children haven't all completed,
2859 2859 * wait for them and then repeat this pipeline stage.
2860 2860 */
2861 2861 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE) ||
2862 2862 zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE) ||
2863 2863 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE) ||
2864 2864 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_DONE))
2865 2865 return (ZIO_PIPELINE_STOP);
2866 2866
2867 2867 for (int c = 0; c < ZIO_CHILD_TYPES; c++)
2868 2868 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
2869 2869 ASSERT(zio->io_children[c][w] == 0);
2870 2870
2871 2871 if (bp != NULL) {
2872 2872 ASSERT(bp->blk_pad[0] == 0);
2873 2873 ASSERT(bp->blk_pad[1] == 0);
2874 2874 ASSERT(bcmp(bp, &zio->io_bp_copy, sizeof (blkptr_t)) == 0 ||
2875 2875 (bp == zio_unique_parent(zio)->io_bp));
2876 2876 if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(bp) &&
2877 2877 zio->io_bp_override == NULL &&
2878 2878 !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) {
2879 2879 ASSERT(!BP_SHOULD_BYTESWAP(bp));
2880 2880 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(bp));
2881 2881 ASSERT(BP_COUNT_GANG(bp) == 0 ||
2882 2882 (BP_COUNT_GANG(bp) == BP_GET_NDVAS(bp)));
2883 2883 }
2884 2884 if (zio->io_flags & ZIO_FLAG_NOPWRITE)
2885 2885 VERIFY(BP_EQUAL(bp, &zio->io_bp_orig));
2886 2886 }
2887 2887
2888 2888 /*
2889 2889 * If there were child vdev/gang/ddt errors, they apply to us now.
2890 2890 */
2891 2891 zio_inherit_child_errors(zio, ZIO_CHILD_VDEV);
2892 2892 zio_inherit_child_errors(zio, ZIO_CHILD_GANG);
2893 2893 zio_inherit_child_errors(zio, ZIO_CHILD_DDT);
2894 2894
2895 2895 /*
2896 2896 * If the I/O on the transformed data was successful, generate any
2897 2897 * checksum reports now while we still have the transformed data.
2898 2898 */
2899 2899 if (zio->io_error == 0) {
2900 2900 while (zio->io_cksum_report != NULL) {
2901 2901 zio_cksum_report_t *zcr = zio->io_cksum_report;
2902 2902 uint64_t align = zcr->zcr_align;
2903 2903 uint64_t asize = P2ROUNDUP(psize, align);
2904 2904 char *abuf = zio->io_data;
2905 2905
2906 2906 if (asize != psize) {
2907 2907 abuf = zio_buf_alloc(asize);
2908 2908 bcopy(zio->io_data, abuf, psize);
2909 2909 bzero(abuf + psize, asize - psize);
2910 2910 }
2911 2911
2912 2912 zio->io_cksum_report = zcr->zcr_next;
2913 2913 zcr->zcr_next = NULL;
2914 2914 zcr->zcr_finish(zcr, abuf);
2915 2915 zfs_ereport_free_checksum(zcr);
2916 2916
2917 2917 if (asize != psize)
2918 2918 zio_buf_free(abuf, asize);
2919 2919 }
2920 2920 }
2921 2921
2922 2922 zio_pop_transforms(zio); /* note: may set zio->io_error */
2923 2923
2924 2924 vdev_stat_update(zio, psize);
2925 2925
2926 2926 if (zio->io_error) {
2927 2927 /*
2928 2928 * If this I/O is attached to a particular vdev,
2929 2929 * generate an error message describing the I/O failure
2930 2930 * at the block level. We ignore these errors if the
2931 2931 * device is currently unavailable.
2932 2932 */
2933 2933 if (zio->io_error != ECKSUM && vd != NULL && !vdev_is_dead(vd))
2934 2934 zfs_ereport_post(FM_EREPORT_ZFS_IO, spa, vd, zio, 0, 0);
2935 2935
2936 2936 if ((zio->io_error == EIO || !(zio->io_flags &
2937 2937 (ZIO_FLAG_SPECULATIVE | ZIO_FLAG_DONT_PROPAGATE))) &&
2938 2938 zio == lio) {
2939 2939 /*
2940 2940 * For logical I/O requests, tell the SPA to log the
2941 2941 * error and generate a logical data ereport.
2942 2942 */
2943 2943 spa_log_error(spa, zio);
2944 2944 zfs_ereport_post(FM_EREPORT_ZFS_DATA, spa, NULL, zio,
2945 2945 0, 0);
2946 2946 }
2947 2947 }
2948 2948
2949 2949 if (zio->io_error && zio == lio) {
2950 2950 /*
2951 2951 * Determine whether zio should be reexecuted. This will
2952 2952 * propagate all the way to the root via zio_notify_parent().
2953 2953 */
2954 2954 ASSERT(vd == NULL && bp != NULL);
2955 2955 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2956 2956
2957 2957 if (IO_IS_ALLOCATING(zio) &&
2958 2958 !(zio->io_flags & ZIO_FLAG_CANFAIL)) {
2959 2959 if (zio->io_error != ENOSPC)
2960 2960 zio->io_reexecute |= ZIO_REEXECUTE_NOW;
2961 2961 else
2962 2962 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
2963 2963 }
2964 2964
2965 2965 if ((zio->io_type == ZIO_TYPE_READ ||
2966 2966 zio->io_type == ZIO_TYPE_FREE) &&
2967 2967 !(zio->io_flags & ZIO_FLAG_SCAN_THREAD) &&
2968 2968 zio->io_error == ENXIO &&
2969 2969 spa_load_state(spa) == SPA_LOAD_NONE &&
2970 2970 spa_get_failmode(spa) != ZIO_FAILURE_MODE_CONTINUE)
2971 2971 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
2972 2972
2973 2973 if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute)
2974 2974 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
2975 2975
2976 2976 /*
2977 2977 * Here is a possibly good place to attempt to do
2978 2978 * either combinatorial reconstruction or error correction
2979 2979 * based on checksums. It also might be a good place
2980 2980 * to send out preliminary ereports before we suspend
2981 2981 * processing.
2982 2982 */
2983 2983 }
2984 2984
2985 2985 /*
2986 2986 * If there were logical child errors, they apply to us now.
2987 2987 * We defer this until now to avoid conflating logical child
2988 2988 * errors with errors that happened to the zio itself when
2989 2989 * updating vdev stats and reporting FMA events above.
2990 2990 */
2991 2991 zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL);
2992 2992
2993 2993 if ((zio->io_error || zio->io_reexecute) &&
2994 2994 IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio &&
2995 2995 !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE)))
2996 2996 zio_dva_unallocate(zio, zio->io_gang_tree, bp);
2997 2997
2998 2998 zio_gang_tree_free(&zio->io_gang_tree);
2999 2999
3000 3000 /*
3001 3001 * Godfather I/Os should never suspend.
3002 3002 */
3003 3003 if ((zio->io_flags & ZIO_FLAG_GODFATHER) &&
3004 3004 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND))
3005 3005 zio->io_reexecute = 0;
3006 3006
3007 3007 if (zio->io_reexecute) {
3008 3008 /*
3009 3009 * This is a logical I/O that wants to reexecute.
3010 3010 *
3011 3011 * Reexecute is top-down. When an i/o fails, if it's not
3012 3012 * the root, it simply notifies its parent and sticks around.
3013 3013 * The parent, seeing that it still has children in zio_done(),
3014 3014 * does the same. This percolates all the way up to the root.
3015 3015 * The root i/o will reexecute or suspend the entire tree.
3016 3016 *
3017 3017 * This approach ensures that zio_reexecute() honors
3018 3018 * all the original i/o dependency relationships, e.g.
3019 3019 * parents not executing until children are ready.
3020 3020 */
3021 3021 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
3022 3022
3023 3023 zio->io_gang_leader = NULL;
3024 3024
3025 3025 mutex_enter(&zio->io_lock);
3026 3026 zio->io_state[ZIO_WAIT_DONE] = 1;
3027 3027 mutex_exit(&zio->io_lock);
3028 3028
3029 3029 /*
3030 3030 * "The Godfather" I/O monitors its children but is
3031 3031 * not a true parent to them. It will track them through
3032 3032 * the pipeline but severs its ties whenever they get into
3033 3033 * trouble (e.g. suspended). This allows "The Godfather"
3034 3034 * I/O to return status without blocking.
3035 3035 */
3036 3036 for (pio = zio_walk_parents(zio); pio != NULL; pio = pio_next) {
3037 3037 zio_link_t *zl = zio->io_walk_link;
3038 3038 pio_next = zio_walk_parents(zio);
3039 3039
3040 3040 if ((pio->io_flags & ZIO_FLAG_GODFATHER) &&
3041 3041 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) {
3042 3042 zio_remove_child(pio, zio, zl);
3043 3043 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3044 3044 }
3045 3045 }
3046 3046
3047 3047 if ((pio = zio_unique_parent(zio)) != NULL) {
3048 3048 /*
3049 3049 * We're not a root i/o, so there's nothing to do
3050 3050 * but notify our parent. Don't propagate errors
3051 3051 * upward since we haven't permanently failed yet.
3052 3052 */
3053 3053 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER));
3054 3054 zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE;
3055 3055 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3056 3056 } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) {
3057 3057 /*
3058 3058 * We'd fail again if we reexecuted now, so suspend
3059 3059 * until conditions improve (e.g. device comes online).
3060 3060 */
3061 3061 zio_suspend(spa, zio);
3062 3062 } else {
3063 3063 /*
3064 3064 * Reexecution is potentially a huge amount of work.
3065 3065 * Hand it off to the otherwise-unused claim taskq.
3066 3066 */
3067 3067 ASSERT(zio->io_tqent.tqent_next == NULL);
3068 3068 spa_taskq_dispatch_ent(spa, ZIO_TYPE_CLAIM,
3069 3069 ZIO_TASKQ_ISSUE, (task_func_t *)zio_reexecute, zio,
3070 3070 0, &zio->io_tqent);
3071 3071 }
3072 3072 return (ZIO_PIPELINE_STOP);
3073 3073 }
3074 3074
3075 3075 ASSERT(zio->io_child_count == 0);
3076 3076 ASSERT(zio->io_reexecute == 0);
3077 3077 ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL));
3078 3078
3079 3079 /*
3080 3080 * Report any checksum errors, since the I/O is complete.
3081 3081 */
3082 3082 while (zio->io_cksum_report != NULL) {
3083 3083 zio_cksum_report_t *zcr = zio->io_cksum_report;
3084 3084 zio->io_cksum_report = zcr->zcr_next;
3085 3085 zcr->zcr_next = NULL;
3086 3086 zcr->zcr_finish(zcr, NULL);
3087 3087 zfs_ereport_free_checksum(zcr);
3088 3088 }
3089 3089
3090 3090 /*
3091 3091 * It is the responsibility of the done callback to ensure that this
3092 3092 * particular zio is no longer discoverable for adoption, and as
3093 3093 * such, cannot acquire any new parents.
3094 3094 */
3095 3095 if (zio->io_done)
3096 3096 zio->io_done(zio);
3097 3097
3098 3098 mutex_enter(&zio->io_lock);
3099 3099 zio->io_state[ZIO_WAIT_DONE] = 1;
3100 3100 mutex_exit(&zio->io_lock);
3101 3101
3102 3102 for (pio = zio_walk_parents(zio); pio != NULL; pio = pio_next) {
3103 3103 zio_link_t *zl = zio->io_walk_link;
3104 3104 pio_next = zio_walk_parents(zio);
3105 3105 zio_remove_child(pio, zio, zl);
3106 3106 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3107 3107 }
3108 3108
3109 3109 if (zio->io_waiter != NULL) {
3110 3110 mutex_enter(&zio->io_lock);
3111 3111 zio->io_executor = NULL;
3112 3112 cv_broadcast(&zio->io_cv);
3113 3113 mutex_exit(&zio->io_lock);
3114 3114 } else {
3115 3115 zio_destroy(zio);
3116 3116 }
3117 3117
3118 3118 return (ZIO_PIPELINE_STOP);
3119 3119 }
3120 3120
3121 3121 /*
3122 3122 * ==========================================================================
3123 3123 * I/O pipeline definition
3124 3124 * ==========================================================================
3125 3125 */
3126 3126 static zio_pipe_stage_t *zio_pipeline[] = {
3127 3127 NULL,
3128 3128 zio_read_bp_init,
3129 3129 zio_free_bp_init,
3130 3130 zio_issue_async,
3131 3131 zio_write_bp_init,
3132 3132 zio_checksum_generate,
3133 3133 zio_nop_write,
3134 3134 zio_ddt_read_start,
3135 3135 zio_ddt_read_done,
3136 3136 zio_ddt_write,
3137 3137 zio_ddt_free,
3138 3138 zio_gang_assemble,
3139 3139 zio_gang_issue,
3140 3140 zio_dva_allocate,
3141 3141 zio_dva_free,
3142 3142 zio_dva_claim,
3143 3143 zio_ready,
3144 3144 zio_vdev_io_start,
3145 3145 zio_vdev_io_done,
3146 3146 zio_vdev_io_assess,
3147 3147 zio_checksum_verify,
3148 3148 zio_done
3149 3149 };
3150 3150
3151 3151 /* dnp is the dnode for zb1->zb_object */
3152 3152 boolean_t
3153 3153 zbookmark_is_before(const dnode_phys_t *dnp, const zbookmark_t *zb1,
3154 3154 const zbookmark_t *zb2)
3155 3155 {
3156 3156 uint64_t zb1nextL0, zb2thisobj;
3157 3157
3158 3158 ASSERT(zb1->zb_objset == zb2->zb_objset);
3159 3159 ASSERT(zb2->zb_level == 0);
3160 3160
3161 3161 /*
3162 3162 * A bookmark in the deadlist is considered to be after
3163 3163 * everything else.
3164 3164 */
3165 3165 if (zb2->zb_object == DMU_DEADLIST_OBJECT)
3166 3166 return (B_TRUE);
3167 3167
3168 3168 /* The objset_phys_t isn't before anything. */
3169 3169 if (dnp == NULL)
3170 3170 return (B_FALSE);
3171 3171
3172 3172 zb1nextL0 = (zb1->zb_blkid + 1) <<
3173 3173 ((zb1->zb_level) * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT));
3174 3174
3175 3175 zb2thisobj = zb2->zb_object ? zb2->zb_object :
3176 3176 zb2->zb_blkid << (DNODE_BLOCK_SHIFT - DNODE_SHIFT);
3177 3177
3178 3178 if (zb1->zb_object == DMU_META_DNODE_OBJECT) {
3179 3179 uint64_t nextobj = zb1nextL0 *
3180 3180 (dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT) >> DNODE_SHIFT;
3181 3181 return (nextobj <= zb2thisobj);
3182 3182 }
3183 3183
3184 3184 if (zb1->zb_object < zb2thisobj)
3185 3185 return (B_TRUE);
3186 3186 if (zb1->zb_object > zb2thisobj)
3187 3187 return (B_FALSE);
3188 3188 if (zb2->zb_object == DMU_META_DNODE_OBJECT)
3189 3189 return (B_FALSE);
3190 3190 return (zb1nextL0 <= zb2->zb_blkid);
3191 3191 }
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