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