1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
25 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
26 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
27 * Copyright 2013 DEY Storage Systems, Inc.
28 * Copyright 2014 HybridCluster. All rights reserved.
29 */
30
31 /* Portions Copyright 2010 Robert Milkowski */
32
33 #ifndef _SYS_DMU_H
34 #define _SYS_DMU_H
35
36 /*
37 * This file describes the interface that the DMU provides for its
38 * consumers.
39 *
40 * The DMU also interacts with the SPA. That interface is described in
41 * dmu_spa.h.
42 */
43
44 #include <sys/inttypes.h>
45 #include <sys/types.h>
46 #include <sys/param.h>
47 #include <sys/cred.h>
48 #include <sys/time.h>
49 #include <sys/fs/zfs.h>
50
51 #ifdef __cplusplus
52 extern "C" {
53 #endif
54
55 struct uio;
56 struct xuio;
57 struct page;
58 struct vnode;
59 struct spa;
60 struct zilog;
61 struct zio;
62 struct blkptr;
63 struct zap_cursor;
64 struct dsl_dataset;
65 struct dsl_pool;
66 struct dnode;
67 struct drr_begin;
68 struct drr_end;
69 struct zbookmark_phys;
70 struct spa;
71 struct nvlist;
72 struct arc_buf;
73 struct zio_prop;
74 struct sa_handle;
75
76 typedef struct objset objset_t;
77 typedef struct dmu_tx dmu_tx_t;
78 typedef struct dsl_dir dsl_dir_t;
79
80 typedef enum dmu_object_byteswap {
81 DMU_BSWAP_UINT8,
82 DMU_BSWAP_UINT16,
83 DMU_BSWAP_UINT32,
84 DMU_BSWAP_UINT64,
85 DMU_BSWAP_ZAP,
86 DMU_BSWAP_DNODE,
87 DMU_BSWAP_OBJSET,
88 DMU_BSWAP_ZNODE,
89 DMU_BSWAP_OLDACL,
90 DMU_BSWAP_ACL,
91 /*
92 * Allocating a new byteswap type number makes the on-disk format
93 * incompatible with any other format that uses the same number.
94 *
95 * Data can usually be structured to work with one of the
96 * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
97 */
98 DMU_BSWAP_NUMFUNCS
99 } dmu_object_byteswap_t;
100
101 #define DMU_OT_NEWTYPE 0x80
102 #define DMU_OT_METADATA 0x40
103 #define DMU_OT_BYTESWAP_MASK 0x3f
104
105 /*
106 * Defines a uint8_t object type. Object types specify if the data
107 * in the object is metadata (boolean) and how to byteswap the data
108 * (dmu_object_byteswap_t).
109 */
110 #define DMU_OT(byteswap, metadata) \
111 (DMU_OT_NEWTYPE | \
112 ((metadata) ? DMU_OT_METADATA : 0) | \
113 ((byteswap) & DMU_OT_BYTESWAP_MASK))
114
115 #define DMU_OT_IS_VALID(ot) (((ot) & DMU_OT_NEWTYPE) ? \
116 ((ot) & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS : \
117 (ot) < DMU_OT_NUMTYPES)
118
119 #define DMU_OT_IS_METADATA(ot) (((ot) & DMU_OT_NEWTYPE) ? \
120 ((ot) & DMU_OT_METADATA) : \
121 dmu_ot[(ot)].ot_metadata)
122
123 /*
124 * These object types use bp_fill != 1 for their L0 bp's. Therefore they can't
125 * have their data embedded (i.e. use a BP_IS_EMBEDDED() bp), because bp_fill
126 * is repurposed for embedded BPs.
127 */
128 #define DMU_OT_HAS_FILL(ot) \
129 ((ot) == DMU_OT_DNODE || (ot) == DMU_OT_OBJSET)
130
131 #define DMU_OT_BYTESWAP(ot) (((ot) & DMU_OT_NEWTYPE) ? \
132 ((ot) & DMU_OT_BYTESWAP_MASK) : \
133 dmu_ot[(ot)].ot_byteswap)
134
135 typedef enum dmu_object_type {
136 DMU_OT_NONE,
137 /* general: */
138 DMU_OT_OBJECT_DIRECTORY, /* ZAP */
139 DMU_OT_OBJECT_ARRAY, /* UINT64 */
140 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */
141 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */
142 DMU_OT_BPOBJ, /* UINT64 */
143 DMU_OT_BPOBJ_HDR, /* UINT64 */
144 /* spa: */
145 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */
146 DMU_OT_SPACE_MAP, /* UINT64 */
147 /* zil: */
148 DMU_OT_INTENT_LOG, /* UINT64 */
149 /* dmu: */
150 DMU_OT_DNODE, /* DNODE */
151 DMU_OT_OBJSET, /* OBJSET */
152 /* dsl: */
153 DMU_OT_DSL_DIR, /* UINT64 */
154 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */
155 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */
156 DMU_OT_DSL_PROPS, /* ZAP */
157 DMU_OT_DSL_DATASET, /* UINT64 */
158 /* zpl: */
159 DMU_OT_ZNODE, /* ZNODE */
160 DMU_OT_OLDACL, /* Old ACL */
161 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */
162 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */
163 DMU_OT_MASTER_NODE, /* ZAP */
164 DMU_OT_UNLINKED_SET, /* ZAP */
165 /* zvol: */
166 DMU_OT_ZVOL, /* UINT8 */
167 DMU_OT_ZVOL_PROP, /* ZAP */
168 /* other; for testing only! */
169 DMU_OT_PLAIN_OTHER, /* UINT8 */
170 DMU_OT_UINT64_OTHER, /* UINT64 */
171 DMU_OT_ZAP_OTHER, /* ZAP */
172 /* new object types: */
173 DMU_OT_ERROR_LOG, /* ZAP */
174 DMU_OT_SPA_HISTORY, /* UINT8 */
175 DMU_OT_SPA_HISTORY_OFFSETS, /* spa_his_phys_t */
176 DMU_OT_POOL_PROPS, /* ZAP */
177 DMU_OT_DSL_PERMS, /* ZAP */
178 DMU_OT_ACL, /* ACL */
179 DMU_OT_SYSACL, /* SYSACL */
180 DMU_OT_FUID, /* FUID table (Packed NVLIST UINT8) */
181 DMU_OT_FUID_SIZE, /* FUID table size UINT64 */
182 DMU_OT_NEXT_CLONES, /* ZAP */
183 DMU_OT_SCAN_QUEUE, /* ZAP */
184 DMU_OT_USERGROUP_USED, /* ZAP */
185 DMU_OT_USERGROUP_QUOTA, /* ZAP */
186 DMU_OT_USERREFS, /* ZAP */
187 DMU_OT_DDT_ZAP, /* ZAP */
188 DMU_OT_DDT_STATS, /* ZAP */
189 DMU_OT_SA, /* System attr */
190 DMU_OT_SA_MASTER_NODE, /* ZAP */
191 DMU_OT_SA_ATTR_REGISTRATION, /* ZAP */
192 DMU_OT_SA_ATTR_LAYOUTS, /* ZAP */
193 DMU_OT_SCAN_XLATE, /* ZAP */
194 DMU_OT_DEDUP, /* fake dedup BP from ddt_bp_create() */
195 DMU_OT_DEADLIST, /* ZAP */
196 DMU_OT_DEADLIST_HDR, /* UINT64 */
197 DMU_OT_DSL_CLONES, /* ZAP */
198 DMU_OT_BPOBJ_SUBOBJ, /* UINT64 */
199 /*
200 * Do not allocate new object types here. Doing so makes the on-disk
201 * format incompatible with any other format that uses the same object
202 * type number.
203 *
204 * When creating an object which does not have one of the above types
205 * use the DMU_OTN_* type with the correct byteswap and metadata
206 * values.
207 *
208 * The DMU_OTN_* types do not have entries in the dmu_ot table,
209 * use the DMU_OT_IS_METDATA() and DMU_OT_BYTESWAP() macros instead
210 * of indexing into dmu_ot directly (this works for both DMU_OT_* types
211 * and DMU_OTN_* types).
212 */
213 DMU_OT_NUMTYPES,
214
215 /*
216 * Names for valid types declared with DMU_OT().
217 */
218 DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE),
219 DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE),
220 DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE),
221 DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE),
222 DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE),
223 DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE),
224 DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE),
225 DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE),
226 DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE),
227 DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE),
228 } dmu_object_type_t;
229
230 typedef enum txg_how {
231 TXG_WAIT = 1,
232 TXG_NOWAIT,
233 TXG_WAITED,
234 } txg_how_t;
235
236 void byteswap_uint64_array(void *buf, size_t size);
237 void byteswap_uint32_array(void *buf, size_t size);
238 void byteswap_uint16_array(void *buf, size_t size);
239 void byteswap_uint8_array(void *buf, size_t size);
240 void zap_byteswap(void *buf, size_t size);
241 void zfs_oldacl_byteswap(void *buf, size_t size);
242 void zfs_acl_byteswap(void *buf, size_t size);
243 void zfs_znode_byteswap(void *buf, size_t size);
244
245 #define DS_FIND_SNAPSHOTS (1<<0)
246 #define DS_FIND_CHILDREN (1<<1)
247
248 /*
249 * The maximum number of bytes that can be accessed as part of one
250 * operation, including metadata.
251 */
252 #define DMU_MAX_ACCESS (32 * 1024 * 1024) /* 32MB */
253 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */
254
255 #define DMU_USERUSED_OBJECT (-1ULL)
256 #define DMU_GROUPUSED_OBJECT (-2ULL)
257
258 /*
259 * artificial blkids for bonus buffer and spill blocks
260 */
261 #define DMU_BONUS_BLKID (-1ULL)
262 #define DMU_SPILL_BLKID (-2ULL)
263 /*
264 * Public routines to create, destroy, open, and close objsets.
265 */
266 int dmu_objset_hold(const char *name, void *tag, objset_t **osp);
267 int dmu_objset_own(const char *name, dmu_objset_type_t type,
268 boolean_t readonly, void *tag, objset_t **osp);
269 void dmu_objset_rele(objset_t *os, void *tag);
270 void dmu_objset_disown(objset_t *os, void *tag);
271 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp);
272
273 void dmu_objset_evict_dbufs(objset_t *os);
274 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
275 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg);
276 int dmu_objset_clone(const char *name, const char *origin);
277 int dsl_destroy_snapshots_nvl(struct nvlist *snaps, boolean_t defer,
278 struct nvlist *errlist);
279 int dmu_objset_snapshot_one(const char *fsname, const char *snapname);
280 int dmu_objset_snapshot_tmp(const char *, const char *, int);
281 int dmu_objset_find(char *name, int func(const char *, void *), void *arg,
282 int flags);
283 void dmu_objset_byteswap(void *buf, size_t size);
284 int dsl_dataset_rename_snapshot(const char *fsname,
285 const char *oldsnapname, const char *newsnapname, boolean_t recursive);
286
287 typedef struct dmu_buf {
288 uint64_t db_object; /* object that this buffer is part of */
289 uint64_t db_offset; /* byte offset in this object */
290 uint64_t db_size; /* size of buffer in bytes */
291 void *db_data; /* data in buffer */
292 } dmu_buf_t;
293
294 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);
295
296 /*
297 * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
298 */
299 #define DMU_POOL_DIRECTORY_OBJECT 1
300 #define DMU_POOL_CONFIG "config"
301 #define DMU_POOL_FEATURES_FOR_WRITE "features_for_write"
302 #define DMU_POOL_FEATURES_FOR_READ "features_for_read"
303 #define DMU_POOL_FEATURE_DESCRIPTIONS "feature_descriptions"
304 #define DMU_POOL_FEATURE_ENABLED_TXG "feature_enabled_txg"
305 #define DMU_POOL_ROOT_DATASET "root_dataset"
306 #define DMU_POOL_SYNC_BPOBJ "sync_bplist"
307 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub"
308 #define DMU_POOL_ERRLOG_LAST "errlog_last"
309 #define DMU_POOL_SPARES "spares"
310 #define DMU_POOL_DEFLATE "deflate"
311 #define DMU_POOL_HISTORY "history"
312 #define DMU_POOL_PROPS "pool_props"
313 #define DMU_POOL_L2CACHE "l2cache"
314 #define DMU_POOL_TMP_USERREFS "tmp_userrefs"
315 #define DMU_POOL_DDT "DDT-%s-%s-%s"
316 #define DMU_POOL_DDT_STATS "DDT-statistics"
317 #define DMU_POOL_CREATION_VERSION "creation_version"
318 #define DMU_POOL_SCAN "scan"
319 #define DMU_POOL_FREE_BPOBJ "free_bpobj"
320 #define DMU_POOL_BPTREE_OBJ "bptree_obj"
321 #define DMU_POOL_EMPTY_BPOBJ "empty_bpobj"
322
323 /*
324 * Allocate an object from this objset. The range of object numbers
325 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode.
326 *
327 * The transaction must be assigned to a txg. The newly allocated
328 * object will be "held" in the transaction (ie. you can modify the
329 * newly allocated object in this transaction).
330 *
331 * dmu_object_alloc() chooses an object and returns it in *objectp.
332 *
333 * dmu_object_claim() allocates a specific object number. If that
334 * number is already allocated, it fails and returns EEXIST.
335 *
336 * Return 0 on success, or ENOSPC or EEXIST as specified above.
337 */
338 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
339 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
340 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
341 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
342 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
343 int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *txp);
344
345 /*
346 * Free an object from this objset.
347 *
348 * The object's data will be freed as well (ie. you don't need to call
349 * dmu_free(object, 0, -1, tx)).
350 *
351 * The object need not be held in the transaction.
352 *
353 * If there are any holds on this object's buffers (via dmu_buf_hold()),
354 * or tx holds on the object (via dmu_tx_hold_object()), you can not
355 * free it; it fails and returns EBUSY.
356 *
357 * If the object is not allocated, it fails and returns ENOENT.
358 *
359 * Return 0 on success, or EBUSY or ENOENT as specified above.
360 */
361 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx);
362
363 /*
364 * Find the next allocated or free object.
365 *
366 * The objectp parameter is in-out. It will be updated to be the next
367 * object which is allocated. Ignore objects which have not been
368 * modified since txg.
369 *
370 * XXX Can only be called on a objset with no dirty data.
371 *
372 * Returns 0 on success, or ENOENT if there are no more objects.
373 */
374 int dmu_object_next(objset_t *os, uint64_t *objectp,
375 boolean_t hole, uint64_t txg);
376
377 /*
378 * Set the data blocksize for an object.
379 *
380 * The object cannot have any blocks allcated beyond the first. If
381 * the first block is allocated already, the new size must be greater
382 * than the current block size. If these conditions are not met,
383 * ENOTSUP will be returned.
384 *
385 * Returns 0 on success, or EBUSY if there are any holds on the object
386 * contents, or ENOTSUP as described above.
387 */
388 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size,
389 int ibs, dmu_tx_t *tx);
390
391 /*
392 * Set the checksum property on a dnode. The new checksum algorithm will
393 * apply to all newly written blocks; existing blocks will not be affected.
394 */
395 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
396 dmu_tx_t *tx);
397
398 /*
399 * Set the compress property on a dnode. The new compression algorithm will
400 * apply to all newly written blocks; existing blocks will not be affected.
401 */
402 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
403 dmu_tx_t *tx);
404
405 void
406 dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset,
407 void *data, uint8_t etype, uint8_t comp, int uncompressed_size,
408 int compressed_size, int byteorder, dmu_tx_t *tx);
409
410 /*
411 * Decide how to write a block: checksum, compression, number of copies, etc.
412 */
413 #define WP_NOFILL 0x1
414 #define WP_DMU_SYNC 0x2
415 #define WP_SPILL 0x4
416
417 void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp,
418 struct zio_prop *zp);
419 /*
420 * The bonus data is accessed more or less like a regular buffer.
421 * You must dmu_bonus_hold() to get the buffer, which will give you a
422 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus
423 * data. As with any normal buffer, you must call dmu_buf_read() to
424 * read db_data, dmu_buf_will_dirty() before modifying it, and the
425 * object must be held in an assigned transaction before calling
426 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus
427 * buffer as well. You must release your hold with dmu_buf_rele().
428 *
429 * Returns ENOENT, EIO, or 0.
430 */
431 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **);
432 int dmu_bonus_max(void);
433 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *);
434 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *);
435 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *);
436 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *);
437
438 /*
439 * Special spill buffer support used by "SA" framework
440 */
441
442 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
443 int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags,
444 void *tag, dmu_buf_t **dbp);
445 int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
446
447 /*
448 * Obtain the DMU buffer from the specified object which contains the
449 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so
450 * that it will remain in memory. You must release the hold with
451 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your
452 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU.
453 *
454 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill
455 * on the returned buffer before reading or writing the buffer's
456 * db_data. The comments for those routines describe what particular
457 * operations are valid after calling them.
458 *
459 * The object number must be a valid, allocated object number.
460 */
461 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
462 void *tag, dmu_buf_t **, int flags);
463 void dmu_buf_add_ref(dmu_buf_t *db, void* tag);
464 void dmu_buf_rele(dmu_buf_t *db, void *tag);
465 uint64_t dmu_buf_refcount(dmu_buf_t *db);
466
467 /*
468 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a
469 * range of an object. A pointer to an array of dmu_buf_t*'s is
470 * returned (in *dbpp).
471 *
472 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and
473 * frees the array. The hold on the array of buffers MUST be released
474 * with dmu_buf_rele_array. You can NOT release the hold on each buffer
475 * individually with dmu_buf_rele.
476 */
477 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
478 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp);
479 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag);
480
481 /*
482 * Returns NULL on success, or the existing user ptr if it's already
483 * been set.
484 *
485 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user().
486 *
487 * If non-NULL, pageout func will be called when this buffer is being
488 * excised from the cache, so that you can clean up the data structure
489 * pointed to by user_ptr.
490 *
491 * dmu_evict_user() will call the pageout func for all buffers in a
492 * objset with a given pageout func.
493 */
494 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr,
495 dmu_buf_evict_func_t *pageout_func);
496 /*
497 * set_user_ie is the same as set_user, but request immediate eviction
498 * when hold count goes to zero.
499 */
500 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr,
501 dmu_buf_evict_func_t *pageout_func);
502 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr,
503 void *user_ptr, dmu_buf_evict_func_t *pageout_func);
504 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func);
505
506 /*
507 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set.
508 */
509 void *dmu_buf_get_user(dmu_buf_t *db);
510
511 /*
512 * Returns the blkptr associated with this dbuf, or NULL if not set.
513 */
514 struct blkptr *dmu_buf_get_blkptr(dmu_buf_t *db);
515
516 /*
517 * Indicate that you are going to modify the buffer's data (db_data).
518 *
519 * The transaction (tx) must be assigned to a txg (ie. you've called
520 * dmu_tx_assign()). The buffer's object must be held in the tx
521 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)).
522 */
523 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);
524
525 /*
526 * Tells if the given dbuf is freeable.
527 */
528 boolean_t dmu_buf_freeable(dmu_buf_t *);
529
530 /*
531 * You must create a transaction, then hold the objects which you will
532 * (or might) modify as part of this transaction. Then you must assign
533 * the transaction to a transaction group. Once the transaction has
534 * been assigned, you can modify buffers which belong to held objects as
535 * part of this transaction. You can't modify buffers before the
536 * transaction has been assigned; you can't modify buffers which don't
537 * belong to objects which this transaction holds; you can't hold
538 * objects once the transaction has been assigned. You may hold an
539 * object which you are going to free (with dmu_object_free()), but you
540 * don't have to.
541 *
542 * You can abort the transaction before it has been assigned.
543 *
544 * Note that you may hold buffers (with dmu_buf_hold) at any time,
545 * regardless of transaction state.
546 */
547
548 #define DMU_NEW_OBJECT (-1ULL)
549 #define DMU_OBJECT_END (-1ULL)
550
551 dmu_tx_t *dmu_tx_create(objset_t *os);
552 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
553 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
554 uint64_t len);
555 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name);
556 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
557 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
558 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
559 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
560 void dmu_tx_abort(dmu_tx_t *tx);
561 int dmu_tx_assign(dmu_tx_t *tx, enum txg_how txg_how);
562 void dmu_tx_wait(dmu_tx_t *tx);
563 void dmu_tx_commit(dmu_tx_t *tx);
564 void dmu_tx_mark_netfree(dmu_tx_t *tx);
565
566 /*
567 * To register a commit callback, dmu_tx_callback_register() must be called.
568 *
569 * dcb_data is a pointer to caller private data that is passed on as a
570 * callback parameter. The caller is responsible for properly allocating and
571 * freeing it.
572 *
573 * When registering a callback, the transaction must be already created, but
574 * it cannot be committed or aborted. It can be assigned to a txg or not.
575 *
576 * The callback will be called after the transaction has been safely written
577 * to stable storage and will also be called if the dmu_tx is aborted.
578 * If there is any error which prevents the transaction from being committed to
579 * disk, the callback will be called with a value of error != 0.
580 */
581 typedef void dmu_tx_callback_func_t(void *dcb_data, int error);
582
583 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
584 void *dcb_data);
585
586 /*
587 * Free up the data blocks for a defined range of a file. If size is
588 * -1, the range from offset to end-of-file is freed.
589 */
590 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
591 uint64_t size, dmu_tx_t *tx);
592 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
593 uint64_t size);
594 int dmu_free_long_object(objset_t *os, uint64_t object);
595
596 /*
597 * Convenience functions.
598 *
599 * Canfail routines will return 0 on success, or an errno if there is a
600 * nonrecoverable I/O error.
601 */
602 #define DMU_READ_PREFETCH 0 /* prefetch */
603 #define DMU_READ_NO_PREFETCH 1 /* don't prefetch */
604 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
605 void *buf, uint32_t flags);
606 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
607 const void *buf, dmu_tx_t *tx);
608 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
609 dmu_tx_t *tx);
610 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size);
611 int dmu_read_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size);
612 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size,
613 dmu_tx_t *tx);
614 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size,
615 dmu_tx_t *tx);
616 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset,
617 uint64_t size, struct page *pp, dmu_tx_t *tx);
618 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size);
619 void dmu_return_arcbuf(struct arc_buf *buf);
620 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf,
621 dmu_tx_t *tx);
622 int dmu_xuio_init(struct xuio *uio, int niov);
623 void dmu_xuio_fini(struct xuio *uio);
624 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off,
625 size_t n);
626 int dmu_xuio_cnt(struct xuio *uio);
627 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i);
628 void dmu_xuio_clear(struct xuio *uio, int i);
629 void xuio_stat_wbuf_copied();
630 void xuio_stat_wbuf_nocopy();
631
632 extern int zfs_prefetch_disable;
633 extern int zfs_max_recordsize;
634
635 /*
636 * Asynchronously try to read in the data.
637 */
638 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset,
639 uint64_t len);
640
641 typedef struct dmu_object_info {
642 /* All sizes are in bytes unless otherwise indicated. */
643 uint32_t doi_data_block_size;
644 uint32_t doi_metadata_block_size;
645 dmu_object_type_t doi_type;
646 dmu_object_type_t doi_bonus_type;
647 uint64_t doi_bonus_size;
648 uint8_t doi_indirection; /* 2 = dnode->indirect->data */
649 uint8_t doi_checksum;
650 uint8_t doi_compress;
651 uint8_t doi_nblkptr;
652 uint8_t doi_pad[4];
653 uint64_t doi_physical_blocks_512; /* data + metadata, 512b blks */
654 uint64_t doi_max_offset;
655 uint64_t doi_fill_count; /* number of non-empty blocks */
656 } dmu_object_info_t;
657
658 typedef void arc_byteswap_func_t(void *buf, size_t size);
659
660 typedef struct dmu_object_type_info {
661 dmu_object_byteswap_t ot_byteswap;
662 boolean_t ot_metadata;
663 char *ot_name;
664 } dmu_object_type_info_t;
665
666 typedef struct dmu_object_byteswap_info {
667 arc_byteswap_func_t *ob_func;
668 char *ob_name;
669 } dmu_object_byteswap_info_t;
670
671 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
672 extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS];
673
674 /*
675 * Get information on a DMU object.
676 *
677 * Return 0 on success or ENOENT if object is not allocated.
678 *
679 * If doi is NULL, just indicates whether the object exists.
680 */
681 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);
682 /* Like dmu_object_info, but faster if you have a held dnode in hand. */
683 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);
684 /* Like dmu_object_info, but faster if you have a held dbuf in hand. */
685 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);
686 /*
687 * Like dmu_object_info_from_db, but faster still when you only care about
688 * the size. This is specifically optimized for zfs_getattr().
689 */
690 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
691 u_longlong_t *nblk512);
692
693 typedef struct dmu_objset_stats {
694 uint64_t dds_num_clones; /* number of clones of this */
695 uint64_t dds_creation_txg;
696 uint64_t dds_guid;
697 dmu_objset_type_t dds_type;
698 uint8_t dds_is_snapshot;
699 uint8_t dds_inconsistent;
700 char dds_origin[MAXNAMELEN];
701 } dmu_objset_stats_t;
702
703 /*
704 * Get stats on a dataset.
705 */
706 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
707
708 /*
709 * Add entries to the nvlist for all the objset's properties. See
710 * zfs_prop_table[] and zfs(1m) for details on the properties.
711 */
712 void dmu_objset_stats(objset_t *os, struct nvlist *nv);
713
714 /*
715 * Get the space usage statistics for statvfs().
716 *
717 * refdbytes is the amount of space "referenced" by this objset.
718 * availbytes is the amount of space available to this objset, taking
719 * into account quotas & reservations, assuming that no other objsets
720 * use the space first. These values correspond to the 'referenced' and
721 * 'available' properties, described in the zfs(1m) manpage.
722 *
723 * usedobjs and availobjs are the number of objects currently allocated,
724 * and available.
725 */
726 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
727 uint64_t *usedobjsp, uint64_t *availobjsp);
728
729 /*
730 * The fsid_guid is a 56-bit ID that can change to avoid collisions.
731 * (Contrast with the ds_guid which is a 64-bit ID that will never
732 * change, so there is a small probability that it will collide.)
733 */
734 uint64_t dmu_objset_fsid_guid(objset_t *os);
735
736 /*
737 * Get the [cm]time for an objset's snapshot dir
738 */
739 timestruc_t dmu_objset_snap_cmtime(objset_t *os);
740
741 int dmu_objset_is_snapshot(objset_t *os);
742
743 extern struct spa *dmu_objset_spa(objset_t *os);
744 extern struct zilog *dmu_objset_zil(objset_t *os);
745 extern struct dsl_pool *dmu_objset_pool(objset_t *os);
746 extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
747 extern void dmu_objset_name(objset_t *os, char *buf);
748 extern dmu_objset_type_t dmu_objset_type(objset_t *os);
749 extern uint64_t dmu_objset_id(objset_t *os);
750 extern zfs_sync_type_t dmu_objset_syncprop(objset_t *os);
751 extern zfs_logbias_op_t dmu_objset_logbias(objset_t *os);
752 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
753 uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
754 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
755 int maxlen, boolean_t *conflict);
756 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
757 uint64_t *idp, uint64_t *offp);
758
759 typedef int objset_used_cb_t(dmu_object_type_t bonustype,
760 void *bonus, uint64_t *userp, uint64_t *groupp);
761 extern void dmu_objset_register_type(dmu_objset_type_t ost,
762 objset_used_cb_t *cb);
763 extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
764 extern void *dmu_objset_get_user(objset_t *os);
765
766 /*
767 * Return the txg number for the given assigned transaction.
768 */
769 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
770
771 /*
772 * Synchronous write.
773 * If a parent zio is provided this function initiates a write on the
774 * provided buffer as a child of the parent zio.
775 * In the absence of a parent zio, the write is completed synchronously.
776 * At write completion, blk is filled with the bp of the written block.
777 * Note that while the data covered by this function will be on stable
778 * storage when the write completes this new data does not become a
779 * permanent part of the file until the associated transaction commits.
780 */
781
782 /*
783 * {zfs,zvol,ztest}_get_done() args
784 */
785 typedef struct zgd {
786 struct zilog *zgd_zilog;
787 struct blkptr *zgd_bp;
788 dmu_buf_t *zgd_db;
789 struct rl *zgd_rl;
790 void *zgd_private;
791 } zgd_t;
792
793 typedef void dmu_sync_cb_t(zgd_t *arg, int error);
794 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd);
795
796 /*
797 * Find the next hole or data block in file starting at *off
798 * Return found offset in *off. Return ESRCH for end of file.
799 */
800 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
801 uint64_t *off);
802
803 /*
804 * Initial setup and final teardown.
805 */
806 extern void dmu_init(void);
807 extern void dmu_fini(void);
808
809 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
810 uint64_t object, uint64_t offset, int len);
811 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
812 dmu_traverse_cb_t cb, void *arg);
813
814 int dmu_diff(const char *tosnap_name, const char *fromsnap_name,
815 struct vnode *vp, offset_t *offp);
816
817 /* CRC64 table */
818 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */
819 extern uint64_t zfs_crc64_table[256];
820
821 extern int zfs_mdcomp_disable;
822
823 #ifdef __cplusplus
824 }
825 #endif
826
827 #endif /* _SYS_DMU_H */