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 */
29
30 /* Portions Copyright 2010 Robert Milkowski */
31
32 #ifndef _SYS_DMU_H
33 #define _SYS_DMU_H
34
35 /*
36 * This file describes the interface that the DMU provides for its
37 * consumers.
38 *
39 * The DMU also interacts with the SPA. That interface is described in
40 * dmu_spa.h.
41 */
42
43 #include <sys/inttypes.h>
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/cred.h>
47 #include <sys/time.h>
48 #include <sys/fs/zfs.h>
49
50 #ifdef __cplusplus
51 extern "C" {
52 #endif
53
54 struct uio;
55 struct xuio;
56 struct page;
57 struct vnode;
58 struct spa;
59 struct zilog;
60 struct zio;
61 struct blkptr;
62 struct zap_cursor;
63 struct dsl_dataset;
64 struct dsl_pool;
65 struct dnode;
66 struct drr_begin;
67 struct drr_end;
68 struct zbookmark;
69 struct spa;
70 struct nvlist;
71 struct arc_buf;
72 struct zio_prop;
73 struct sa_handle;
74
75 typedef struct objset objset_t;
76 typedef struct dmu_tx dmu_tx_t;
77 typedef struct dsl_dir dsl_dir_t;
78
79 typedef enum dmu_object_byteswap {
80 DMU_BSWAP_UINT8,
81 DMU_BSWAP_UINT16,
82 DMU_BSWAP_UINT32,
83 DMU_BSWAP_UINT64,
84 DMU_BSWAP_ZAP,
85 DMU_BSWAP_DNODE,
86 DMU_BSWAP_OBJSET,
87 DMU_BSWAP_ZNODE,
88 DMU_BSWAP_OLDACL,
89 DMU_BSWAP_ACL,
90 /*
91 * Allocating a new byteswap type number makes the on-disk format
92 * incompatible with any other format that uses the same number.
93 *
94 * Data can usually be structured to work with one of the
95 * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
96 */
97 DMU_BSWAP_NUMFUNCS
98 } dmu_object_byteswap_t;
99
100 #define DMU_OT_NEWTYPE 0x80
101 #define DMU_OT_METADATA 0x40
102 #define DMU_OT_BYTESWAP_MASK 0x3f
103
104 /*
105 * Defines a uint8_t object type. Object types specify if the data
106 * in the object is metadata (boolean) and how to byteswap the data
107 * (dmu_object_byteswap_t).
108 */
109 #define DMU_OT(byteswap, metadata) \
110 (DMU_OT_NEWTYPE | \
111 ((metadata) ? DMU_OT_METADATA : 0) | \
112 ((byteswap) & DMU_OT_BYTESWAP_MASK))
113
114 #define DMU_OT_IS_VALID(ot) (((ot) & DMU_OT_NEWTYPE) ? \
115 ((ot) & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS : \
116 (ot) < DMU_OT_NUMTYPES)
117
118 #define DMU_OT_IS_METADATA(ot) (((ot) & DMU_OT_NEWTYPE) ? \
119 ((ot) & DMU_OT_METADATA) : \
120 dmu_ot[(ot)].ot_metadata)
121
122 /*
123 * These object types use bp_fill != 1 for their L0 bp's. Therefore they can't
124 * have their data embedded (i.e. use a BP_IS_EMBEDDED() bp), because bp_fill
125 * is repurposed for embedded BPs.
126 */
127 #define DMU_OT_HAS_FILL(ot) \
128 ((ot) == DMU_OT_DNODE || (ot) == DMU_OT_OBJSET)
129
130 #define DMU_OT_BYTESWAP(ot) (((ot) & DMU_OT_NEWTYPE) ? \
131 ((ot) & DMU_OT_BYTESWAP_MASK) : \
132 dmu_ot[(ot)].ot_byteswap)
133
134 typedef enum dmu_object_type {
135 DMU_OT_NONE,
136 /* general: */
137 DMU_OT_OBJECT_DIRECTORY, /* ZAP */
138 DMU_OT_OBJECT_ARRAY, /* UINT64 */
139 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */
140 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */
141 DMU_OT_BPOBJ, /* UINT64 */
142 DMU_OT_BPOBJ_HDR, /* UINT64 */
143 /* spa: */
144 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */
145 DMU_OT_SPACE_MAP, /* UINT64 */
146 /* zil: */
147 DMU_OT_INTENT_LOG, /* UINT64 */
148 /* dmu: */
149 DMU_OT_DNODE, /* DNODE */
150 DMU_OT_OBJSET, /* OBJSET */
151 /* dsl: */
152 DMU_OT_DSL_DIR, /* UINT64 */
153 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */
154 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */
155 DMU_OT_DSL_PROPS, /* ZAP */
156 DMU_OT_DSL_DATASET, /* UINT64 */
157 /* zpl: */
158 DMU_OT_ZNODE, /* ZNODE */
159 DMU_OT_OLDACL, /* Old ACL */
160 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */
161 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */
162 DMU_OT_MASTER_NODE, /* ZAP */
163 DMU_OT_UNLINKED_SET, /* ZAP */
164 /* zvol: */
165 DMU_OT_ZVOL, /* UINT8 */
166 DMU_OT_ZVOL_PROP, /* ZAP */
167 /* other; for testing only! */
168 DMU_OT_PLAIN_OTHER, /* UINT8 */
169 DMU_OT_UINT64_OTHER, /* UINT64 */
170 DMU_OT_ZAP_OTHER, /* ZAP */
171 /* new object types: */
172 DMU_OT_ERROR_LOG, /* ZAP */
173 DMU_OT_SPA_HISTORY, /* UINT8 */
174 DMU_OT_SPA_HISTORY_OFFSETS, /* spa_his_phys_t */
175 DMU_OT_POOL_PROPS, /* ZAP */
176 DMU_OT_DSL_PERMS, /* ZAP */
177 DMU_OT_ACL, /* ACL */
178 DMU_OT_SYSACL, /* SYSACL */
179 DMU_OT_FUID, /* FUID table (Packed NVLIST UINT8) */
180 DMU_OT_FUID_SIZE, /* FUID table size UINT64 */
181 DMU_OT_NEXT_CLONES, /* ZAP */
182 DMU_OT_SCAN_QUEUE, /* ZAP */
183 DMU_OT_USERGROUP_USED, /* ZAP */
184 DMU_OT_USERGROUP_QUOTA, /* ZAP */
185 DMU_OT_USERREFS, /* ZAP */
186 DMU_OT_DDT_ZAP, /* ZAP */
187 DMU_OT_DDT_STATS, /* ZAP */
188 DMU_OT_SA, /* System attr */
189 DMU_OT_SA_MASTER_NODE, /* ZAP */
190 DMU_OT_SA_ATTR_REGISTRATION, /* ZAP */
191 DMU_OT_SA_ATTR_LAYOUTS, /* ZAP */
192 DMU_OT_SCAN_XLATE, /* ZAP */
193 DMU_OT_DEDUP, /* fake dedup BP from ddt_bp_create() */
194 DMU_OT_DEADLIST, /* ZAP */
195 DMU_OT_DEADLIST_HDR, /* UINT64 */
196 DMU_OT_DSL_CLONES, /* ZAP */
197 DMU_OT_BPOBJ_SUBOBJ, /* UINT64 */
198 /*
199 * Do not allocate new object types here. Doing so makes the on-disk
200 * format incompatible with any other format that uses the same object
201 * type number.
202 *
203 * When creating an object which does not have one of the above types
204 * use the DMU_OTN_* type with the correct byteswap and metadata
205 * values.
206 *
207 * The DMU_OTN_* types do not have entries in the dmu_ot table,
208 * use the DMU_OT_IS_METDATA() and DMU_OT_BYTESWAP() macros instead
209 * of indexing into dmu_ot directly (this works for both DMU_OT_* types
210 * and DMU_OTN_* types).
211 */
212 DMU_OT_NUMTYPES,
213
214 /*
215 * Names for valid types declared with DMU_OT().
216 */
217 DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE),
218 DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE),
219 DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE),
220 DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE),
221 DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE),
222 DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE),
223 DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE),
224 DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE),
225 DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE),
226 DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE),
227 } dmu_object_type_t;
228
229 typedef enum txg_how {
230 TXG_WAIT = 1,
231 TXG_NOWAIT,
232 TXG_WAITED,
233 } txg_how_t;
234
235 void byteswap_uint64_array(void *buf, size_t size);
236 void byteswap_uint32_array(void *buf, size_t size);
237 void byteswap_uint16_array(void *buf, size_t size);
238 void byteswap_uint8_array(void *buf, size_t size);
239 void zap_byteswap(void *buf, size_t size);
240 void zfs_oldacl_byteswap(void *buf, size_t size);
241 void zfs_acl_byteswap(void *buf, size_t size);
242 void zfs_znode_byteswap(void *buf, size_t size);
243
244 #define DS_FIND_SNAPSHOTS (1<<0)
245 #define DS_FIND_CHILDREN (1<<1)
246
247 /*
248 * The maximum number of bytes that can be accessed as part of one
249 * operation, including metadata.
250 */
251 #define DMU_MAX_ACCESS (10<<20) /* 10MB */
252 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */
253
254 #define DMU_USERUSED_OBJECT (-1ULL)
255 #define DMU_GROUPUSED_OBJECT (-2ULL)
256
257 /*
258 * artificial blkids for bonus buffer and spill blocks
259 */
260 #define DMU_BONUS_BLKID (-1ULL)
261 #define DMU_SPILL_BLKID (-2ULL)
262 /*
263 * Public routines to create, destroy, open, and close objsets.
264 */
265 int dmu_objset_hold(const char *name, void *tag, objset_t **osp);
266 int dmu_objset_own(const char *name, dmu_objset_type_t type,
267 boolean_t readonly, void *tag, objset_t **osp);
268 void dmu_objset_rele(objset_t *os, void *tag);
269 void dmu_objset_rele_obj(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);
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 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which
488 * will be set to db->db_data when you are allowed to access it. Note
489 * that db->db_data (the pointer) can change when you do dmu_buf_read(),
490 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill().
491 * *user_data_ptr_ptr will be set to the new value when it changes.
492 *
493 * If non-NULL, pageout func will be called when this buffer is being
494 * excised from the cache, so that you can clean up the data structure
495 * pointed to by user_ptr.
496 *
497 * dmu_evict_user() will call the pageout func for all buffers in a
498 * objset with a given pageout func.
499 */
500 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr,
501 dmu_buf_evict_func_t *pageout_func);
502 /*
503 * set_user_ie is the same as set_user, but request immediate eviction
504 * when hold count goes to zero.
505 */
506 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr,
507 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func);
508 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr,
509 void *user_ptr, void *user_data_ptr_ptr,
510 dmu_buf_evict_func_t *pageout_func);
511 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func);
512
513 /*
514 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set.
515 */
516 void *dmu_buf_get_user(dmu_buf_t *db);
517
518 /*
519 * Returns the blkptr associated with this dbuf, or NULL if not set.
520 */
521 struct blkptr *dmu_buf_get_blkptr(dmu_buf_t *db);
522
523 /*
524 * Indicate that you are going to modify the buffer's data (db_data).
525 *
526 * The transaction (tx) must be assigned to a txg (ie. you've called
527 * dmu_tx_assign()). The buffer's object must be held in the tx
528 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)).
529 */
530 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);
531
532 /*
533 * Tells if the given dbuf is freeable.
534 */
535 boolean_t dmu_buf_freeable(dmu_buf_t *);
536
537 /*
538 * You must create a transaction, then hold the objects which you will
539 * (or might) modify as part of this transaction. Then you must assign
540 * the transaction to a transaction group. Once the transaction has
541 * been assigned, you can modify buffers which belong to held objects as
542 * part of this transaction. You can't modify buffers before the
543 * transaction has been assigned; you can't modify buffers which don't
544 * belong to objects which this transaction holds; you can't hold
545 * objects once the transaction has been assigned. You may hold an
546 * object which you are going to free (with dmu_object_free()), but you
547 * don't have to.
548 *
549 * You can abort the transaction before it has been assigned.
550 *
551 * Note that you may hold buffers (with dmu_buf_hold) at any time,
552 * regardless of transaction state.
553 */
554
555 #define DMU_NEW_OBJECT (-1ULL)
556 #define DMU_OBJECT_END (-1ULL)
557
558 dmu_tx_t *dmu_tx_create(objset_t *os);
559 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
560 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
561 uint64_t len);
562 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name);
563 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
564 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
565 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
566 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
567 void dmu_tx_abort(dmu_tx_t *tx);
568 int dmu_tx_assign(dmu_tx_t *tx, enum txg_how txg_how);
569 void dmu_tx_wait(dmu_tx_t *tx);
570 void dmu_tx_commit(dmu_tx_t *tx);
571
572 /*
573 * To register a commit callback, dmu_tx_callback_register() must be called.
574 *
575 * dcb_data is a pointer to caller private data that is passed on as a
576 * callback parameter. The caller is responsible for properly allocating and
577 * freeing it.
578 *
579 * When registering a callback, the transaction must be already created, but
580 * it cannot be committed or aborted. It can be assigned to a txg or not.
581 *
582 * The callback will be called after the transaction has been safely written
583 * to stable storage and will also be called if the dmu_tx is aborted.
584 * If there is any error which prevents the transaction from being committed to
585 * disk, the callback will be called with a value of error != 0.
586 */
587 typedef void dmu_tx_callback_func_t(void *dcb_data, int error);
588
589 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
590 void *dcb_data);
591
592 /*
593 * Free up the data blocks for a defined range of a file. If size is
594 * -1, the range from offset to end-of-file is freed.
595 */
596 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
597 uint64_t size, dmu_tx_t *tx);
598 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
599 uint64_t size);
600 int dmu_free_long_object(objset_t *os, uint64_t object);
601
602 /*
603 * Convenience functions.
604 *
605 * Canfail routines will return 0 on success, or an errno if there is a
606 * nonrecoverable I/O error.
607 */
608 #define DMU_READ_PREFETCH 0 /* prefetch */
609 #define DMU_READ_NO_PREFETCH 1 /* don't prefetch */
610 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
611 void *buf, uint32_t flags);
612 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
613 const void *buf, dmu_tx_t *tx);
614 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
615 dmu_tx_t *tx);
616 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size);
617 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size,
618 dmu_tx_t *tx);
619 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size,
620 dmu_tx_t *tx);
621 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset,
622 uint64_t size, struct page *pp, dmu_tx_t *tx);
623 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size);
624 void dmu_return_arcbuf(struct arc_buf *buf);
625 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf,
626 dmu_tx_t *tx);
627 int dmu_xuio_init(struct xuio *uio, int niov);
628 void dmu_xuio_fini(struct xuio *uio);
629 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off,
630 size_t n);
631 int dmu_xuio_cnt(struct xuio *uio);
632 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i);
633 void dmu_xuio_clear(struct xuio *uio, int i);
634 void xuio_stat_wbuf_copied();
635 void xuio_stat_wbuf_nocopy();
636
637 extern int zfs_prefetch_disable;
638
639 /*
640 * Asynchronously try to read in the data.
641 */
642 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset,
643 uint64_t len);
644
645 typedef struct dmu_object_info {
646 /* All sizes are in bytes unless otherwise indicated. */
647 uint32_t doi_data_block_size;
648 uint32_t doi_metadata_block_size;
649 dmu_object_type_t doi_type;
650 dmu_object_type_t doi_bonus_type;
651 uint64_t doi_bonus_size;
652 uint8_t doi_indirection; /* 2 = dnode->indirect->data */
653 uint8_t doi_checksum;
654 uint8_t doi_compress;
655 uint8_t doi_pad[5];
656 uint64_t doi_physical_blocks_512; /* data + metadata, 512b blks */
657 uint64_t doi_max_offset;
658 uint64_t doi_fill_count; /* number of non-empty blocks */
659 } dmu_object_info_t;
660
661 typedef void arc_byteswap_func_t(void *buf, size_t size);
662
663 typedef struct dmu_object_type_info {
664 dmu_object_byteswap_t ot_byteswap;
665 boolean_t ot_metadata;
666 char *ot_name;
667 } dmu_object_type_info_t;
668
669 typedef struct dmu_object_byteswap_info {
670 arc_byteswap_func_t *ob_func;
671 char *ob_name;
672 } dmu_object_byteswap_info_t;
673
674 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
675 extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS];
676
677 /*
678 * Get information on a DMU object.
679 *
680 * Return 0 on success or ENOENT if object is not allocated.
681 *
682 * If doi is NULL, just indicates whether the object exists.
683 */
684 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);
685 /* Like dmu_object_info, but faster if you have a held dnode in hand. */
686 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);
687 /* Like dmu_object_info, but faster if you have a held dbuf in hand. */
688 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);
689 /*
690 * Like dmu_object_info_from_db, but faster still when you only care about
691 * the size. This is specifically optimized for zfs_getattr().
692 */
693 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
694 u_longlong_t *nblk512);
695
696 typedef struct dmu_objset_stats {
697 uint64_t dds_num_clones; /* number of clones of this */
698 uint64_t dds_creation_txg;
699 uint64_t dds_guid;
700 dmu_objset_type_t dds_type;
701 uint8_t dds_is_snapshot;
702 uint8_t dds_inconsistent;
703 char dds_origin[MAXNAMELEN];
704 } dmu_objset_stats_t;
705
706 /*
707 * Get stats on a dataset.
708 */
709 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
710
711 /*
712 * Add entries to the nvlist for all the objset's properties. See
713 * zfs_prop_table[] and zfs(1m) for details on the properties.
714 */
715 void dmu_objset_stats(objset_t *os, struct nvlist *nv);
716
717 /*
718 * Get the space usage statistics for statvfs().
719 *
720 * refdbytes is the amount of space "referenced" by this objset.
721 * availbytes is the amount of space available to this objset, taking
722 * into account quotas & reservations, assuming that no other objsets
723 * use the space first. These values correspond to the 'referenced' and
724 * 'available' properties, described in the zfs(1m) manpage.
725 *
726 * usedobjs and availobjs are the number of objects currently allocated,
727 * and available.
728 */
729 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
730 uint64_t *usedobjsp, uint64_t *availobjsp);
731
732 /*
733 * The fsid_guid is a 56-bit ID that can change to avoid collisions.
734 * (Contrast with the ds_guid which is a 64-bit ID that will never
735 * change, so there is a small probability that it will collide.)
736 */
737 uint64_t dmu_objset_fsid_guid(objset_t *os);
738
739 /*
740 * Get the [cm]time for an objset's snapshot dir
741 */
742 timestruc_t dmu_objset_snap_cmtime(objset_t *os);
743
744 int dmu_objset_is_snapshot(objset_t *os);
745
746 extern struct spa *dmu_objset_spa(objset_t *os);
747 extern struct zilog *dmu_objset_zil(objset_t *os);
748 extern struct dsl_pool *dmu_objset_pool(objset_t *os);
749 extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
750 extern void dmu_objset_name(objset_t *os, char *buf);
751 extern dmu_objset_type_t dmu_objset_type(objset_t *os);
752 extern uint64_t dmu_objset_id(objset_t *os);
753 extern zfs_sync_type_t dmu_objset_syncprop(objset_t *os);
754 extern zfs_logbias_op_t dmu_objset_logbias(objset_t *os);
755 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
756 uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
757 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
758 int maxlen, boolean_t *conflict);
759 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
760 uint64_t *idp, uint64_t *offp);
761
762 typedef int objset_used_cb_t(dmu_object_type_t bonustype,
763 void *bonus, uint64_t *userp, uint64_t *groupp);
764 extern void dmu_objset_register_type(dmu_objset_type_t ost,
765 objset_used_cb_t *cb);
766 extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
767 extern void *dmu_objset_get_user(objset_t *os);
768
769 /*
770 * Return the txg number for the given assigned transaction.
771 */
772 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
773
774 /*
775 * Synchronous write.
776 * If a parent zio is provided this function initiates a write on the
777 * provided buffer as a child of the parent zio.
778 * In the absence of a parent zio, the write is completed synchronously.
779 * At write completion, blk is filled with the bp of the written block.
780 * Note that while the data covered by this function will be on stable
781 * storage when the write completes this new data does not become a
782 * permanent part of the file until the associated transaction commits.
783 */
784
785 /*
786 * {zfs,zvol,ztest}_get_done() args
787 */
788 typedef struct zgd {
789 struct zilog *zgd_zilog;
790 struct blkptr *zgd_bp;
791 dmu_buf_t *zgd_db;
792 struct rl *zgd_rl;
793 void *zgd_private;
794 } zgd_t;
795
796 typedef void dmu_sync_cb_t(zgd_t *arg, int error);
797 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd);
798
799 /*
800 * Find the next hole or data block in file starting at *off
801 * Return found offset in *off. Return ESRCH for end of file.
802 */
803 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
804 uint64_t *off);
805
806 /*
807 * Initial setup and final teardown.
808 */
809 extern void dmu_init(void);
810 extern void dmu_fini(void);
811
812 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
813 uint64_t object, uint64_t offset, int len);
814 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
815 dmu_traverse_cb_t cb, void *arg);
816
817 int dmu_diff(const char *tosnap_name, const char *fromsnap_name,
818 struct vnode *vp, offset_t *offp);
819
820 /* CRC64 table */
821 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */
822 extern uint64_t zfs_crc64_table[256];
823
824 extern int zfs_mdcomp_disable;
825
826 #ifdef __cplusplus
827 }
828 #endif
829
830 #endif /* _SYS_DMU_H */