xref: /freebsd/sys/contrib/openzfs/include/sys/dmu.h (revision 7a7741af18d6c8a804cc643cb7ecda9d730c6aa6)
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 https://opensource.org/licenses/CDDL-1.0.
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  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, 2020 by Delphix. All rights reserved.
24  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
25  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
26  * Copyright 2014 HybridCluster. All rights reserved.
27  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
28  * Copyright 2013 Saso Kiselkov. All rights reserved.
29  * Copyright (c) 2017, Intel Corporation.
30  * Copyright (c) 2022 Hewlett Packard Enterprise Development LP.
31  */
32 
33 /* Portions Copyright 2010 Robert Milkowski */
34 
35 #ifndef	_SYS_DMU_H
36 #define	_SYS_DMU_H
37 
38 /*
39  * This file describes the interface that the DMU provides for its
40  * consumers.
41  *
42  * The DMU also interacts with the SPA.  That interface is described in
43  * dmu_spa.h.
44  */
45 
46 #include <sys/zfs_context.h>
47 #include <sys/inttypes.h>
48 #include <sys/cred.h>
49 #include <sys/fs/zfs.h>
50 #include <sys/zio_compress.h>
51 #include <sys/zio_priority.h>
52 #include <sys/uio.h>
53 #include <sys/zfs_file.h>
54 
55 #ifdef	__cplusplus
56 extern "C" {
57 #endif
58 
59 struct page;
60 struct vnode;
61 struct spa;
62 struct zilog;
63 struct zio;
64 struct blkptr;
65 struct zap_cursor;
66 struct dsl_dataset;
67 struct dsl_pool;
68 struct dnode;
69 struct drr_begin;
70 struct drr_end;
71 struct zbookmark_phys;
72 struct spa;
73 struct nvlist;
74 struct arc_buf;
75 struct zio_prop;
76 struct sa_handle;
77 struct dsl_crypto_params;
78 struct locked_range;
79 
80 typedef struct objset objset_t;
81 typedef struct dmu_tx dmu_tx_t;
82 typedef struct dsl_dir dsl_dir_t;
83 typedef struct dnode dnode_t;
84 
85 typedef enum dmu_object_byteswap {
86 	DMU_BSWAP_UINT8,
87 	DMU_BSWAP_UINT16,
88 	DMU_BSWAP_UINT32,
89 	DMU_BSWAP_UINT64,
90 	DMU_BSWAP_ZAP,
91 	DMU_BSWAP_DNODE,
92 	DMU_BSWAP_OBJSET,
93 	DMU_BSWAP_ZNODE,
94 	DMU_BSWAP_OLDACL,
95 	DMU_BSWAP_ACL,
96 	/*
97 	 * Allocating a new byteswap type number makes the on-disk format
98 	 * incompatible with any other format that uses the same number.
99 	 *
100 	 * Data can usually be structured to work with one of the
101 	 * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
102 	 */
103 	DMU_BSWAP_NUMFUNCS
104 } dmu_object_byteswap_t;
105 
106 #define	DMU_OT_NEWTYPE 0x80
107 #define	DMU_OT_METADATA 0x40
108 #define	DMU_OT_ENCRYPTED 0x20
109 #define	DMU_OT_BYTESWAP_MASK 0x1f
110 
111 /*
112  * Defines a uint8_t object type. Object types specify if the data
113  * in the object is metadata (boolean) and how to byteswap the data
114  * (dmu_object_byteswap_t). All of the types created by this method
115  * are cached in the dbuf metadata cache.
116  */
117 #define	DMU_OT(byteswap, metadata, encrypted) \
118 	(DMU_OT_NEWTYPE | \
119 	((metadata) ? DMU_OT_METADATA : 0) | \
120 	((encrypted) ? DMU_OT_ENCRYPTED : 0) | \
121 	((byteswap) & DMU_OT_BYTESWAP_MASK))
122 
123 #define	DMU_OT_IS_VALID(ot) (((ot) & DMU_OT_NEWTYPE) ? \
124 	((ot) & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS : \
125 	(ot) < DMU_OT_NUMTYPES)
126 
127 #define	DMU_OT_IS_METADATA_CACHED(ot) (((ot) & DMU_OT_NEWTYPE) ? \
128 	B_TRUE : dmu_ot[(ot)].ot_dbuf_metadata_cache)
129 
130 /*
131  * MDB doesn't have dmu_ot; it defines these macros itself.
132  */
133 #ifndef ZFS_MDB
134 #define	DMU_OT_IS_METADATA_IMPL(ot) (dmu_ot[ot].ot_metadata)
135 #define	DMU_OT_IS_ENCRYPTED_IMPL(ot) (dmu_ot[ot].ot_encrypt)
136 #define	DMU_OT_BYTESWAP_IMPL(ot) (dmu_ot[ot].ot_byteswap)
137 #endif
138 
139 #define	DMU_OT_IS_METADATA(ot) (((ot) & DMU_OT_NEWTYPE) ? \
140 	(((ot) & DMU_OT_METADATA) != 0) : \
141 	DMU_OT_IS_METADATA_IMPL(ot))
142 
143 #define	DMU_OT_IS_DDT(ot) \
144 	((ot) == DMU_OT_DDT_ZAP)
145 
146 #define	DMU_OT_IS_CRITICAL(ot) \
147 	(DMU_OT_IS_METADATA(ot) && \
148 	(ot) != DMU_OT_DNODE && \
149 	(ot) != DMU_OT_DIRECTORY_CONTENTS && \
150 	(ot) != DMU_OT_SA)
151 
152 /* Note: ztest uses DMU_OT_UINT64_OTHER as a proxy for file blocks */
153 #define	DMU_OT_IS_FILE(ot) \
154 	((ot) == DMU_OT_PLAIN_FILE_CONTENTS || (ot) == DMU_OT_UINT64_OTHER)
155 
156 #define	DMU_OT_IS_ENCRYPTED(ot) (((ot) & DMU_OT_NEWTYPE) ? \
157 	(((ot) & DMU_OT_ENCRYPTED) != 0) : \
158 	DMU_OT_IS_ENCRYPTED_IMPL(ot))
159 
160 /*
161  * These object types use bp_fill != 1 for their L0 bp's. Therefore they can't
162  * have their data embedded (i.e. use a BP_IS_EMBEDDED() bp), because bp_fill
163  * is repurposed for embedded BPs.
164  */
165 #define	DMU_OT_HAS_FILL(ot) \
166 	((ot) == DMU_OT_DNODE || (ot) == DMU_OT_OBJSET)
167 
168 #define	DMU_OT_BYTESWAP(ot) (((ot) & DMU_OT_NEWTYPE) ? \
169 	((ot) & DMU_OT_BYTESWAP_MASK) : \
170 	DMU_OT_BYTESWAP_IMPL(ot))
171 
172 typedef enum dmu_object_type {
173 	DMU_OT_NONE,
174 	/* general: */
175 	DMU_OT_OBJECT_DIRECTORY,	/* ZAP */
176 	DMU_OT_OBJECT_ARRAY,		/* UINT64 */
177 	DMU_OT_PACKED_NVLIST,		/* UINT8 (XDR by nvlist_pack/unpack) */
178 	DMU_OT_PACKED_NVLIST_SIZE,	/* UINT64 */
179 	DMU_OT_BPOBJ,			/* UINT64 */
180 	DMU_OT_BPOBJ_HDR,		/* UINT64 */
181 	/* spa: */
182 	DMU_OT_SPACE_MAP_HEADER,	/* UINT64 */
183 	DMU_OT_SPACE_MAP,		/* UINT64 */
184 	/* zil: */
185 	DMU_OT_INTENT_LOG,		/* UINT64 */
186 	/* dmu: */
187 	DMU_OT_DNODE,			/* DNODE */
188 	DMU_OT_OBJSET,			/* OBJSET */
189 	/* dsl: */
190 	DMU_OT_DSL_DIR,			/* UINT64 */
191 	DMU_OT_DSL_DIR_CHILD_MAP,	/* ZAP */
192 	DMU_OT_DSL_DS_SNAP_MAP,		/* ZAP */
193 	DMU_OT_DSL_PROPS,		/* ZAP */
194 	DMU_OT_DSL_DATASET,		/* UINT64 */
195 	/* zpl: */
196 	DMU_OT_ZNODE,			/* ZNODE */
197 	DMU_OT_OLDACL,			/* Old ACL */
198 	DMU_OT_PLAIN_FILE_CONTENTS,	/* UINT8 */
199 	DMU_OT_DIRECTORY_CONTENTS,	/* ZAP */
200 	DMU_OT_MASTER_NODE,		/* ZAP */
201 	DMU_OT_UNLINKED_SET,		/* ZAP */
202 	/* zvol: */
203 	DMU_OT_ZVOL,			/* UINT8 */
204 	DMU_OT_ZVOL_PROP,		/* ZAP */
205 	/* other; for testing only! */
206 	DMU_OT_PLAIN_OTHER,		/* UINT8 */
207 	DMU_OT_UINT64_OTHER,		/* UINT64 */
208 	DMU_OT_ZAP_OTHER,		/* ZAP */
209 	/* new object types: */
210 	DMU_OT_ERROR_LOG,		/* ZAP */
211 	DMU_OT_SPA_HISTORY,		/* UINT8 */
212 	DMU_OT_SPA_HISTORY_OFFSETS,	/* spa_his_phys_t */
213 	DMU_OT_POOL_PROPS,		/* ZAP */
214 	DMU_OT_DSL_PERMS,		/* ZAP */
215 	DMU_OT_ACL,			/* ACL */
216 	DMU_OT_SYSACL,			/* SYSACL */
217 	DMU_OT_FUID,			/* FUID table (Packed NVLIST UINT8) */
218 	DMU_OT_FUID_SIZE,		/* FUID table size UINT64 */
219 	DMU_OT_NEXT_CLONES,		/* ZAP */
220 	DMU_OT_SCAN_QUEUE,		/* ZAP */
221 	DMU_OT_USERGROUP_USED,		/* ZAP */
222 	DMU_OT_USERGROUP_QUOTA,		/* ZAP */
223 	DMU_OT_USERREFS,		/* ZAP */
224 	DMU_OT_DDT_ZAP,			/* ZAP */
225 	DMU_OT_DDT_STATS,		/* ZAP */
226 	DMU_OT_SA,			/* System attr */
227 	DMU_OT_SA_MASTER_NODE,		/* ZAP */
228 	DMU_OT_SA_ATTR_REGISTRATION,	/* ZAP */
229 	DMU_OT_SA_ATTR_LAYOUTS,		/* ZAP */
230 	DMU_OT_SCAN_XLATE,		/* ZAP */
231 	DMU_OT_DEDUP,			/* fake dedup BP from ddt_bp_create() */
232 	DMU_OT_DEADLIST,		/* ZAP */
233 	DMU_OT_DEADLIST_HDR,		/* UINT64 */
234 	DMU_OT_DSL_CLONES,		/* ZAP */
235 	DMU_OT_BPOBJ_SUBOBJ,		/* UINT64 */
236 	/*
237 	 * Do not allocate new object types here. Doing so makes the on-disk
238 	 * format incompatible with any other format that uses the same object
239 	 * type number.
240 	 *
241 	 * When creating an object which does not have one of the above types
242 	 * use the DMU_OTN_* type with the correct byteswap and metadata
243 	 * values.
244 	 *
245 	 * The DMU_OTN_* types do not have entries in the dmu_ot table,
246 	 * use the DMU_OT_IS_METADATA() and DMU_OT_BYTESWAP() macros instead
247 	 * of indexing into dmu_ot directly (this works for both DMU_OT_* types
248 	 * and DMU_OTN_* types).
249 	 */
250 	DMU_OT_NUMTYPES,
251 
252 	/*
253 	 * Names for valid types declared with DMU_OT().
254 	 */
255 	DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE, B_FALSE),
256 	DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE, B_FALSE),
257 	DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE, B_FALSE),
258 	DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE, B_FALSE),
259 	DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE, B_FALSE),
260 	DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE, B_FALSE),
261 	DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE, B_FALSE),
262 	DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE, B_FALSE),
263 	DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE, B_FALSE),
264 	DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE, B_FALSE),
265 
266 	DMU_OTN_UINT8_ENC_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE, B_TRUE),
267 	DMU_OTN_UINT8_ENC_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE, B_TRUE),
268 	DMU_OTN_UINT16_ENC_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE, B_TRUE),
269 	DMU_OTN_UINT16_ENC_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE, B_TRUE),
270 	DMU_OTN_UINT32_ENC_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE, B_TRUE),
271 	DMU_OTN_UINT32_ENC_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE, B_TRUE),
272 	DMU_OTN_UINT64_ENC_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE, B_TRUE),
273 	DMU_OTN_UINT64_ENC_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE, B_TRUE),
274 	DMU_OTN_ZAP_ENC_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE, B_TRUE),
275 	DMU_OTN_ZAP_ENC_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE, B_TRUE),
276 } dmu_object_type_t;
277 
278 /*
279  * These flags are intended to be used to specify the "txg_how"
280  * parameter when calling the dmu_tx_assign() function. See the comment
281  * above dmu_tx_assign() for more details on the meaning of these flags.
282  */
283 #define	TXG_NOWAIT	(0ULL)
284 #define	TXG_WAIT	(1ULL<<0)
285 #define	TXG_NOTHROTTLE	(1ULL<<1)
286 
287 void byteswap_uint64_array(void *buf, size_t size);
288 void byteswap_uint32_array(void *buf, size_t size);
289 void byteswap_uint16_array(void *buf, size_t size);
290 void byteswap_uint8_array(void *buf, size_t size);
291 void zap_byteswap(void *buf, size_t size);
292 void zfs_oldacl_byteswap(void *buf, size_t size);
293 void zfs_acl_byteswap(void *buf, size_t size);
294 void zfs_znode_byteswap(void *buf, size_t size);
295 
296 #define	DS_FIND_SNAPSHOTS	(1<<0)
297 #define	DS_FIND_CHILDREN	(1<<1)
298 #define	DS_FIND_SERIALIZE	(1<<2)
299 
300 /*
301  * The maximum number of bytes that can be accessed as part of one
302  * operation, including metadata.
303  */
304 #define	DMU_MAX_ACCESS (64 * 1024 * 1024) /* 64MB */
305 #define	DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */
306 
307 #define	DMU_USERUSED_OBJECT	(-1ULL)
308 #define	DMU_GROUPUSED_OBJECT	(-2ULL)
309 #define	DMU_PROJECTUSED_OBJECT	(-3ULL)
310 
311 /*
312  * Zap prefix for object accounting in DMU_{USER,GROUP,PROJECT}USED_OBJECT.
313  */
314 #define	DMU_OBJACCT_PREFIX	"obj-"
315 #define	DMU_OBJACCT_PREFIX_LEN	4
316 
317 /*
318  * artificial blkids for bonus buffer and spill blocks
319  */
320 #define	DMU_BONUS_BLKID		(-1ULL)
321 #define	DMU_SPILL_BLKID		(-2ULL)
322 
323 /*
324  * Public routines to create, destroy, open, and close objsets.
325  */
326 typedef void dmu_objset_create_sync_func_t(objset_t *os, void *arg,
327     cred_t *cr, dmu_tx_t *tx);
328 
329 int dmu_objset_hold(const char *name, const void *tag, objset_t **osp);
330 int dmu_objset_own(const char *name, dmu_objset_type_t type,
331     boolean_t readonly, boolean_t key_required, const void *tag,
332     objset_t **osp);
333 void dmu_objset_rele(objset_t *os, const void *tag);
334 void dmu_objset_disown(objset_t *os, boolean_t key_required, const void *tag);
335 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp);
336 
337 void dmu_objset_evict_dbufs(objset_t *os);
338 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
339     struct dsl_crypto_params *dcp, dmu_objset_create_sync_func_t func,
340     void *arg);
341 int dmu_objset_clone(const char *name, const char *origin);
342 int dsl_destroy_snapshots_nvl(struct nvlist *snaps, boolean_t defer,
343     struct nvlist *errlist);
344 int dmu_objset_snapshot_one(const char *fsname, const char *snapname);
345 int dmu_objset_find(const char *name, int func(const char *, void *), void *arg,
346     int flags);
347 void dmu_objset_byteswap(void *buf, size_t size);
348 int dsl_dataset_rename_snapshot(const char *fsname,
349     const char *oldsnapname, const char *newsnapname, boolean_t recursive);
350 
351 typedef struct dmu_buf {
352 	uint64_t db_object;		/* object that this buffer is part of */
353 	uint64_t db_offset;		/* byte offset in this object */
354 	uint64_t db_size;		/* size of buffer in bytes */
355 	void *db_data;			/* data in buffer */
356 } dmu_buf_t;
357 
358 /*
359  * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
360  */
361 #define	DMU_POOL_DIRECTORY_OBJECT	1
362 #define	DMU_POOL_CONFIG			"config"
363 #define	DMU_POOL_FEATURES_FOR_WRITE	"features_for_write"
364 #define	DMU_POOL_FEATURES_FOR_READ	"features_for_read"
365 #define	DMU_POOL_FEATURE_DESCRIPTIONS	"feature_descriptions"
366 #define	DMU_POOL_FEATURE_ENABLED_TXG	"feature_enabled_txg"
367 #define	DMU_POOL_ROOT_DATASET		"root_dataset"
368 #define	DMU_POOL_SYNC_BPOBJ		"sync_bplist"
369 #define	DMU_POOL_ERRLOG_SCRUB		"errlog_scrub"
370 #define	DMU_POOL_ERRLOG_LAST		"errlog_last"
371 #define	DMU_POOL_SPARES			"spares"
372 #define	DMU_POOL_DEFLATE		"deflate"
373 #define	DMU_POOL_HISTORY		"history"
374 #define	DMU_POOL_PROPS			"pool_props"
375 #define	DMU_POOL_L2CACHE		"l2cache"
376 #define	DMU_POOL_TMP_USERREFS		"tmp_userrefs"
377 #define	DMU_POOL_DDT			"DDT-%s-%s-%s"
378 #define	DMU_POOL_DDT_LOG		"DDT-log-%s-%u"
379 #define	DMU_POOL_DDT_STATS		"DDT-statistics"
380 #define	DMU_POOL_DDT_DIR		"DDT-%s"
381 #define	DMU_POOL_CREATION_VERSION	"creation_version"
382 #define	DMU_POOL_SCAN			"scan"
383 #define	DMU_POOL_ERRORSCRUB		"error_scrub"
384 #define	DMU_POOL_FREE_BPOBJ		"free_bpobj"
385 #define	DMU_POOL_BPTREE_OBJ		"bptree_obj"
386 #define	DMU_POOL_EMPTY_BPOBJ		"empty_bpobj"
387 #define	DMU_POOL_CHECKSUM_SALT		"org.illumos:checksum_salt"
388 #define	DMU_POOL_VDEV_ZAP_MAP		"com.delphix:vdev_zap_map"
389 #define	DMU_POOL_REMOVING		"com.delphix:removing"
390 #define	DMU_POOL_OBSOLETE_BPOBJ		"com.delphix:obsolete_bpobj"
391 #define	DMU_POOL_CONDENSING_INDIRECT	"com.delphix:condensing_indirect"
392 #define	DMU_POOL_ZPOOL_CHECKPOINT	"com.delphix:zpool_checkpoint"
393 #define	DMU_POOL_LOG_SPACEMAP_ZAP	"com.delphix:log_spacemap_zap"
394 #define	DMU_POOL_DELETED_CLONES		"com.delphix:deleted_clones"
395 
396 /*
397  * Allocate an object from this objset.  The range of object numbers
398  * available is (0, DN_MAX_OBJECT).  Object 0 is the meta-dnode.
399  *
400  * The transaction must be assigned to a txg.  The newly allocated
401  * object will be "held" in the transaction (ie. you can modify the
402  * newly allocated object in this transaction).
403  *
404  * dmu_object_alloc() chooses an object and returns it in *objectp.
405  *
406  * dmu_object_claim() allocates a specific object number.  If that
407  * number is already allocated, it fails and returns EEXIST.
408  *
409  * Return 0 on success, or ENOSPC or EEXIST as specified above.
410  */
411 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
412     int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
413 uint64_t dmu_object_alloc_ibs(objset_t *os, dmu_object_type_t ot, int blocksize,
414     int indirect_blockshift,
415     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
416 uint64_t dmu_object_alloc_dnsize(objset_t *os, dmu_object_type_t ot,
417     int blocksize, dmu_object_type_t bonus_type, int bonus_len,
418     int dnodesize, dmu_tx_t *tx);
419 uint64_t dmu_object_alloc_hold(objset_t *os, dmu_object_type_t ot,
420     int blocksize, int indirect_blockshift, dmu_object_type_t bonustype,
421     int bonuslen, int dnodesize, dnode_t **allocated_dnode, const void *tag,
422     dmu_tx_t *tx);
423 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
424     int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
425 int dmu_object_claim_dnsize(objset_t *os, uint64_t object, dmu_object_type_t ot,
426     int blocksize, dmu_object_type_t bonus_type, int bonus_len,
427     int dnodesize, dmu_tx_t *tx);
428 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
429     int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *txp);
430 int dmu_object_reclaim_dnsize(objset_t *os, uint64_t object,
431     dmu_object_type_t ot, int blocksize, dmu_object_type_t bonustype,
432     int bonuslen, int dnodesize, boolean_t keep_spill, dmu_tx_t *tx);
433 int dmu_object_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx);
434 
435 /*
436  * Free an object from this objset.
437  *
438  * The object's data will be freed as well (ie. you don't need to call
439  * dmu_free(object, 0, -1, tx)).
440  *
441  * The object need not be held in the transaction.
442  *
443  * If there are any holds on this object's buffers (via dmu_buf_hold()),
444  * or tx holds on the object (via dmu_tx_hold_object()), you can not
445  * free it; it fails and returns EBUSY.
446  *
447  * If the object is not allocated, it fails and returns ENOENT.
448  *
449  * Return 0 on success, or EBUSY or ENOENT as specified above.
450  */
451 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx);
452 
453 /*
454  * Find the next allocated or free object.
455  *
456  * The objectp parameter is in-out.  It will be updated to be the next
457  * object which is allocated.  Ignore objects which have not been
458  * modified since txg.
459  *
460  * XXX Can only be called on a objset with no dirty data.
461  *
462  * Returns 0 on success, or ENOENT if there are no more objects.
463  */
464 int dmu_object_next(objset_t *os, uint64_t *objectp,
465     boolean_t hole, uint64_t txg);
466 
467 /*
468  * Set the number of levels on a dnode. nlevels must be greater than the
469  * current number of levels or an EINVAL will be returned.
470  */
471 int dmu_object_set_nlevels(objset_t *os, uint64_t object, int nlevels,
472     dmu_tx_t *tx);
473 
474 /*
475  * Set the data blocksize for an object.
476  *
477  * The object cannot have any blocks allocated beyond the first.  If
478  * the first block is allocated already, the new size must be greater
479  * than the current block size.  If these conditions are not met,
480  * ENOTSUP will be returned.
481  *
482  * Returns 0 on success, or EBUSY if there are any holds on the object
483  * contents, or ENOTSUP as described above.
484  */
485 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size,
486     int ibs, dmu_tx_t *tx);
487 
488 /*
489  * Manually set the maxblkid on a dnode. This will adjust nlevels accordingly
490  * to accommodate the change. When calling this function, the caller must
491  * ensure that the object's nlevels can sufficiently support the new maxblkid.
492  */
493 int dmu_object_set_maxblkid(objset_t *os, uint64_t object, uint64_t maxblkid,
494     dmu_tx_t *tx);
495 
496 /*
497  * Set the checksum property on a dnode.  The new checksum algorithm will
498  * apply to all newly written blocks; existing blocks will not be affected.
499  */
500 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
501     dmu_tx_t *tx);
502 
503 /*
504  * Set the compress property on a dnode.  The new compression algorithm will
505  * apply to all newly written blocks; existing blocks will not be affected.
506  */
507 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
508     dmu_tx_t *tx);
509 
510 /*
511  * Get an estimated cache size for an object. Caller must expect races.
512  */
513 int dmu_object_cached_size(objset_t *os, uint64_t object,
514     uint64_t *l1sz, uint64_t *l2sz);
515 
516 void dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset,
517     void *data, uint8_t etype, uint8_t comp, int uncompressed_size,
518     int compressed_size, int byteorder, dmu_tx_t *tx);
519 void dmu_redact(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
520     dmu_tx_t *tx);
521 
522 /*
523  * Decide how to write a block: checksum, compression, number of copies, etc.
524  */
525 #define	WP_NOFILL	0x1
526 #define	WP_DMU_SYNC	0x2
527 #define	WP_SPILL	0x4
528 #define	WP_DIRECT_WR	0x8
529 
530 void dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp,
531     struct zio_prop *zp);
532 
533 /*
534  * The bonus data is accessed more or less like a regular buffer.
535  * You must dmu_bonus_hold() to get the buffer, which will give you a
536  * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus
537  * data.  As with any normal buffer, you must call dmu_buf_will_dirty()
538  * before modifying it, and the
539  * object must be held in an assigned transaction before calling
540  * dmu_buf_will_dirty.  You may use dmu_buf_set_user() on the bonus
541  * buffer as well.  You must release what you hold with dmu_buf_rele().
542  *
543  * Returns ENOENT, EIO, or 0.
544  */
545 int dmu_bonus_hold(objset_t *os, uint64_t object, const void *tag,
546     dmu_buf_t **dbp);
547 int dmu_bonus_hold_by_dnode(dnode_t *dn, const void *tag, dmu_buf_t **dbp,
548     uint32_t flags);
549 int dmu_bonus_max(void);
550 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *);
551 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *);
552 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *);
553 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *);
554 
555 /*
556  * Special spill buffer support used by "SA" framework
557  */
558 
559 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, uint32_t flags, const void *tag,
560     dmu_buf_t **dbp);
561 int dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags,
562     const void *tag, dmu_buf_t **dbp);
563 int dmu_spill_hold_existing(dmu_buf_t *bonus, const void *tag, dmu_buf_t **dbp);
564 
565 /*
566  * Obtain the DMU buffer from the specified object which contains the
567  * specified offset.  dmu_buf_hold() puts a "hold" on the buffer, so
568  * that it will remain in memory.  You must release the hold with
569  * dmu_buf_rele().  You must not access the dmu_buf_t after releasing
570  * what you hold.  You must have a hold on any dmu_buf_t* you pass to the DMU.
571  *
572  * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill
573  * on the returned buffer before reading or writing the buffer's
574  * db_data.  The comments for those routines describe what particular
575  * operations are valid after calling them.
576  *
577  * The object number must be a valid, allocated object number.
578  */
579 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
580     const void *tag, dmu_buf_t **, int flags);
581 int dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
582     uint64_t length, int read, const void *tag, int *numbufsp,
583     dmu_buf_t ***dbpp);
584 int dmu_buf_hold_noread(objset_t *os, uint64_t object, uint64_t offset,
585     const void *tag, dmu_buf_t **dbp);
586 int dmu_buf_hold_by_dnode(dnode_t *dn, uint64_t offset,
587     const void *tag, dmu_buf_t **dbp, int flags);
588 int dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset,
589     uint64_t length, boolean_t read, const void *tag, int *numbufsp,
590     dmu_buf_t ***dbpp, uint32_t flags);
591 int dmu_buf_hold_noread_by_dnode(dnode_t *dn, uint64_t offset, const void *tag,
592     dmu_buf_t **dbp);
593 
594 /*
595  * Add a reference to a dmu buffer that has already been held via
596  * dmu_buf_hold() in the current context.
597  */
598 void dmu_buf_add_ref(dmu_buf_t *db, const void *tag);
599 
600 /*
601  * Attempt to add a reference to a dmu buffer that is in an unknown state,
602  * using a pointer that may have been invalidated by eviction processing.
603  * The request will succeed if the passed in dbuf still represents the
604  * same os/object/blkid, is ineligible for eviction, and has at least
605  * one hold by a user other than the syncer.
606  */
607 boolean_t dmu_buf_try_add_ref(dmu_buf_t *, objset_t *os, uint64_t object,
608     uint64_t blkid, const void *tag);
609 
610 void dmu_buf_rele(dmu_buf_t *db, const void *tag);
611 uint64_t dmu_buf_refcount(dmu_buf_t *db);
612 uint64_t dmu_buf_user_refcount(dmu_buf_t *db);
613 
614 /*
615  * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a
616  * range of an object.  A pointer to an array of dmu_buf_t*'s is
617  * returned (in *dbpp).
618  *
619  * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and
620  * frees the array.  The hold on the array of buffers MUST be released
621  * with dmu_buf_rele_array.  You can NOT release the hold on each buffer
622  * individually with dmu_buf_rele.
623  */
624 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
625     uint64_t length, boolean_t read, const void *tag,
626     int *numbufsp, dmu_buf_t ***dbpp);
627 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, const void *tag);
628 
629 typedef void dmu_buf_evict_func_t(void *user_ptr);
630 
631 /*
632  * A DMU buffer user object may be associated with a dbuf for the
633  * duration of its lifetime.  This allows the user of a dbuf (client)
634  * to attach private data to a dbuf (e.g. in-core only data such as a
635  * dnode_children_t, zap_t, or zap_leaf_t) and be optionally notified
636  * when that dbuf has been evicted.  Clients typically respond to the
637  * eviction notification by freeing their private data, thus ensuring
638  * the same lifetime for both dbuf and private data.
639  *
640  * The mapping from a dmu_buf_user_t to any client private data is the
641  * client's responsibility.  All current consumers of the API with private
642  * data embed a dmu_buf_user_t as the first member of the structure for
643  * their private data.  This allows conversions between the two types
644  * with a simple cast.  Since the DMU buf user API never needs access
645  * to the private data, other strategies can be employed if necessary
646  * or convenient for the client (e.g. using container_of() to do the
647  * conversion for private data that cannot have the dmu_buf_user_t as
648  * its first member).
649  *
650  * Eviction callbacks are executed without the dbuf mutex held or any
651  * other type of mechanism to guarantee that the dbuf is still available.
652  * For this reason, users must assume the dbuf has already been freed
653  * and not reference the dbuf from the callback context.
654  *
655  * Users requesting "immediate eviction" are notified as soon as the dbuf
656  * is only referenced by dirty records (dirties == holds).  Otherwise the
657  * notification occurs after eviction processing for the dbuf begins.
658  */
659 typedef struct dmu_buf_user {
660 	/*
661 	 * Asynchronous user eviction callback state.
662 	 */
663 	taskq_ent_t	dbu_tqent;
664 
665 	/* Size of user data, for inclusion in dbuf_cache accounting. */
666 	uint64_t	dbu_size;
667 
668 	/*
669 	 * This instance's eviction function pointers.
670 	 *
671 	 * dbu_evict_func_sync is called synchronously and then
672 	 * dbu_evict_func_async is executed asynchronously on a taskq.
673 	 */
674 	dmu_buf_evict_func_t *dbu_evict_func_sync;
675 	dmu_buf_evict_func_t *dbu_evict_func_async;
676 #ifdef ZFS_DEBUG
677 	/*
678 	 * Pointer to user's dbuf pointer.  NULL for clients that do
679 	 * not associate a dbuf with their user data.
680 	 *
681 	 * The dbuf pointer is cleared upon eviction so as to catch
682 	 * use-after-evict bugs in clients.
683 	 */
684 	dmu_buf_t **dbu_clear_on_evict_dbufp;
685 #endif
686 } dmu_buf_user_t;
687 
688 /*
689  * Initialize the given dmu_buf_user_t instance with the eviction function
690  * evict_func, to be called when the user is evicted.
691  *
692  * NOTE: This function should only be called once on a given dmu_buf_user_t.
693  *       To allow enforcement of this, dbu must already be zeroed on entry.
694  */
695 static inline void
dmu_buf_init_user(dmu_buf_user_t * dbu,dmu_buf_evict_func_t * evict_func_sync,dmu_buf_evict_func_t * evict_func_async,dmu_buf_t ** clear_on_evict_dbufp __maybe_unused)696 dmu_buf_init_user(dmu_buf_user_t *dbu, dmu_buf_evict_func_t *evict_func_sync,
697     dmu_buf_evict_func_t *evict_func_async,
698     dmu_buf_t **clear_on_evict_dbufp __maybe_unused)
699 {
700 	ASSERT(dbu->dbu_evict_func_sync == NULL);
701 	ASSERT(dbu->dbu_evict_func_async == NULL);
702 
703 	/* must have at least one evict func */
704 	IMPLY(evict_func_sync == NULL, evict_func_async != NULL);
705 	dbu->dbu_evict_func_sync = evict_func_sync;
706 	dbu->dbu_evict_func_async = evict_func_async;
707 	taskq_init_ent(&dbu->dbu_tqent);
708 #ifdef ZFS_DEBUG
709 	dbu->dbu_clear_on_evict_dbufp = clear_on_evict_dbufp;
710 #endif
711 }
712 
713 /*
714  * Attach user data to a dbuf and mark it for normal (when the dbuf's
715  * data is cleared or its reference count goes to zero) eviction processing.
716  *
717  * Returns NULL on success, or the existing user if another user currently
718  * owns the buffer.
719  */
720 void *dmu_buf_set_user(dmu_buf_t *db, dmu_buf_user_t *user);
721 
722 /*
723  * Attach user data to a dbuf and mark it for immediate (its dirty and
724  * reference counts are equal) eviction processing.
725  *
726  * Returns NULL on success, or the existing user if another user currently
727  * owns the buffer.
728  */
729 void *dmu_buf_set_user_ie(dmu_buf_t *db, dmu_buf_user_t *user);
730 
731 /*
732  * Replace the current user of a dbuf.
733  *
734  * If given the current user of a dbuf, replaces the dbuf's user with
735  * "new_user" and returns the user data pointer that was replaced.
736  * Otherwise returns the current, and unmodified, dbuf user pointer.
737  */
738 void *dmu_buf_replace_user(dmu_buf_t *db,
739     dmu_buf_user_t *old_user, dmu_buf_user_t *new_user);
740 
741 /*
742  * Remove the specified user data for a DMU buffer.
743  *
744  * Returns the user that was removed on success, or the current user if
745  * another user currently owns the buffer.
746  */
747 void *dmu_buf_remove_user(dmu_buf_t *db, dmu_buf_user_t *user);
748 
749 /*
750  * User data size accounting. This can be used to artifically inflate the size
751  * of the dbuf during cache accounting, so that dbuf_evict_thread evicts enough
752  * to satisfy memory reclaim requests. It's not used for anything else, and
753  * defaults to 0.
754  */
755 uint64_t dmu_buf_user_size(dmu_buf_t *db);
756 void dmu_buf_add_user_size(dmu_buf_t *db, uint64_t nadd);
757 void dmu_buf_sub_user_size(dmu_buf_t *db, uint64_t nsub);
758 
759 /*
760  * Returns the user data (dmu_buf_user_t *) associated with this dbuf.
761  */
762 void *dmu_buf_get_user(dmu_buf_t *db);
763 
764 objset_t *dmu_buf_get_objset(dmu_buf_t *db);
765 
766 /* Block until any in-progress dmu buf user evictions complete. */
767 void dmu_buf_user_evict_wait(void);
768 
769 /*
770  * Returns the blkptr associated with this dbuf, or NULL if not set.
771  */
772 struct blkptr *dmu_buf_get_blkptr(dmu_buf_t *db);
773 
774 /*
775  * Indicate that you are going to modify the buffer's data (db_data).
776  *
777  * The transaction (tx) must be assigned to a txg (ie. you've called
778  * dmu_tx_assign()).  The buffer's object must be held in the tx
779  * (ie. you've called dmu_tx_hold_object(tx, db->db_object)).
780  */
781 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);
782 boolean_t dmu_buf_is_dirty(dmu_buf_t *db, dmu_tx_t *tx);
783 void dmu_buf_set_crypt_params(dmu_buf_t *db_fake, boolean_t byteorder,
784     const uint8_t *salt, const uint8_t *iv, const uint8_t *mac, dmu_tx_t *tx);
785 
786 /*
787  * You must create a transaction, then hold the objects which you will
788  * (or might) modify as part of this transaction.  Then you must assign
789  * the transaction to a transaction group.  Once the transaction has
790  * been assigned, you can modify buffers which belong to held objects as
791  * part of this transaction.  You can't modify buffers before the
792  * transaction has been assigned; you can't modify buffers which don't
793  * belong to objects which this transaction holds; you can't hold
794  * objects once the transaction has been assigned.  You may hold an
795  * object which you are going to free (with dmu_object_free()), but you
796  * don't have to.
797  *
798  * You can abort the transaction before it has been assigned.
799  *
800  * Note that you may hold buffers (with dmu_buf_hold) at any time,
801  * regardless of transaction state.
802  */
803 
804 #define	DMU_NEW_OBJECT	(-1ULL)
805 #define	DMU_OBJECT_END	(-1ULL)
806 
807 dmu_tx_t *dmu_tx_create(objset_t *os);
808 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
809 void dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,
810     int len);
811 void dmu_tx_hold_append(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
812 void dmu_tx_hold_append_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,
813     int len);
814 void dmu_tx_hold_clone_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,
815     int len);
816 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
817     uint64_t len);
818 void dmu_tx_hold_free_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,
819     uint64_t len);
820 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name);
821 void dmu_tx_hold_zap_by_dnode(dmu_tx_t *tx, dnode_t *dn, int add,
822     const char *name);
823 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
824 void dmu_tx_hold_bonus_by_dnode(dmu_tx_t *tx, dnode_t *dn);
825 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
826 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
827 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
828 void dmu_tx_abort(dmu_tx_t *tx);
829 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
830 void dmu_tx_wait(dmu_tx_t *tx);
831 void dmu_tx_commit(dmu_tx_t *tx);
832 void dmu_tx_mark_netfree(dmu_tx_t *tx);
833 
834 /*
835  * To register a commit callback, dmu_tx_callback_register() must be called.
836  *
837  * dcb_data is a pointer to caller private data that is passed on as a
838  * callback parameter. The caller is responsible for properly allocating and
839  * freeing it.
840  *
841  * When registering a callback, the transaction must be already created, but
842  * it cannot be committed or aborted. It can be assigned to a txg or not.
843  *
844  * The callback will be called after the transaction has been safely written
845  * to stable storage and will also be called if the dmu_tx is aborted.
846  * If there is any error which prevents the transaction from being committed to
847  * disk, the callback will be called with a value of error != 0.
848  *
849  * When multiple callbacks are registered to the transaction, the callbacks
850  * will be called in reverse order to let Lustre, the only user of commit
851  * callback currently, take the fast path of its commit callback handling.
852  */
853 typedef void dmu_tx_callback_func_t(void *dcb_data, int error);
854 
855 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
856     void *dcb_data);
857 void dmu_tx_do_callbacks(list_t *cb_list, int error);
858 
859 /*
860  * Free up the data blocks for a defined range of a file.  If size is
861  * -1, the range from offset to end-of-file is freed.
862  */
863 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
864     uint64_t size, dmu_tx_t *tx);
865 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
866     uint64_t size);
867 int dmu_free_long_object(objset_t *os, uint64_t object);
868 
869 /*
870  * Convenience functions.
871  *
872  * Canfail routines will return 0 on success, or an errno if there is a
873  * nonrecoverable I/O error.
874  */
875 #define	DMU_READ_PREFETCH	0 /* prefetch */
876 #define	DMU_READ_NO_PREFETCH	1 /* don't prefetch */
877 #define	DMU_READ_NO_DECRYPT	2 /* don't decrypt */
878 #define	DMU_DIRECTIO		4 /* use Direct I/O */
879 
880 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
881     void *buf, uint32_t flags);
882 int dmu_read_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, void *buf,
883     uint32_t flags);
884 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
885     const void *buf, dmu_tx_t *tx);
886 int dmu_write_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size,
887     const void *buf, dmu_tx_t *tx);
888 int dmu_write_by_dnode_flags(dnode_t *dn, uint64_t offset, uint64_t size,
889     const void *buf, dmu_tx_t *tx, uint32_t flags);
890 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
891     dmu_tx_t *tx);
892 #ifdef _KERNEL
893 int dmu_read_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size);
894 int dmu_read_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size);
895 int dmu_read_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size);
896 int dmu_write_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size,
897 	dmu_tx_t *tx);
898 int dmu_write_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size,
899 	dmu_tx_t *tx);
900 int dmu_write_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size,
901 	dmu_tx_t *tx);
902 #endif
903 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size);
904 void dmu_return_arcbuf(struct arc_buf *buf);
905 int dmu_assign_arcbuf_by_dnode(dnode_t *dn, uint64_t offset,
906     struct arc_buf *buf, dmu_tx_t *tx);
907 int dmu_assign_arcbuf_by_dbuf(dmu_buf_t *handle, uint64_t offset,
908     struct arc_buf *buf, dmu_tx_t *tx);
909 #define	dmu_assign_arcbuf	dmu_assign_arcbuf_by_dbuf
910 extern uint_t zfs_max_recordsize;
911 
912 /*
913  * Asynchronously try to read in the data.
914  */
915 void dmu_prefetch(objset_t *os, uint64_t object, int64_t level, uint64_t offset,
916 	uint64_t len, enum zio_priority pri);
917 void dmu_prefetch_by_dnode(dnode_t *dn, int64_t level, uint64_t offset,
918 	uint64_t len, enum zio_priority pri);
919 void dmu_prefetch_dnode(objset_t *os, uint64_t object, enum zio_priority pri);
920 int dmu_prefetch_wait(objset_t *os, uint64_t object, uint64_t offset,
921     uint64_t size);
922 
923 typedef struct dmu_object_info {
924 	/* All sizes are in bytes unless otherwise indicated. */
925 	uint32_t doi_data_block_size;
926 	uint32_t doi_metadata_block_size;
927 	dmu_object_type_t doi_type;
928 	dmu_object_type_t doi_bonus_type;
929 	uint64_t doi_bonus_size;
930 	uint8_t doi_indirection;		/* 2 = dnode->indirect->data */
931 	uint8_t doi_checksum;
932 	uint8_t doi_compress;
933 	uint8_t doi_nblkptr;
934 	uint8_t doi_pad[4];
935 	uint64_t doi_dnodesize;
936 	uint64_t doi_physical_blocks_512;	/* data + metadata, 512b blks */
937 	uint64_t doi_max_offset;
938 	uint64_t doi_fill_count;		/* number of non-empty blocks */
939 } dmu_object_info_t;
940 
941 typedef void (*const arc_byteswap_func_t)(void *buf, size_t size);
942 
943 typedef struct dmu_object_type_info {
944 	dmu_object_byteswap_t	ot_byteswap;
945 	boolean_t		ot_metadata;
946 	boolean_t		ot_dbuf_metadata_cache;
947 	boolean_t		ot_encrypt;
948 	const char		*ot_name;
949 } dmu_object_type_info_t;
950 
951 typedef const struct dmu_object_byteswap_info {
952 	arc_byteswap_func_t	 ob_func;
953 	const char		*ob_name;
954 } dmu_object_byteswap_info_t;
955 
956 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
957 extern dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS];
958 
959 /*
960  * Get information on a DMU object.
961  *
962  * Return 0 on success or ENOENT if object is not allocated.
963  *
964  * If doi is NULL, just indicates whether the object exists.
965  */
966 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);
967 void __dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);
968 /* Like dmu_object_info, but faster if you have a held dnode in hand. */
969 void dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi);
970 /* Like dmu_object_info, but faster if you have a held dbuf in hand. */
971 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);
972 /*
973  * Like dmu_object_info_from_db, but faster still when you only care about
974  * the size.
975  */
976 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
977     u_longlong_t *nblk512);
978 
979 void dmu_object_dnsize_from_db(dmu_buf_t *db, int *dnsize);
980 
981 typedef struct dmu_objset_stats {
982 	uint64_t dds_num_clones; /* number of clones of this */
983 	uint64_t dds_creation_txg;
984 	uint64_t dds_guid;
985 	dmu_objset_type_t dds_type;
986 	uint8_t dds_is_snapshot;
987 	uint8_t dds_inconsistent;
988 	uint8_t dds_redacted;
989 	char dds_origin[ZFS_MAX_DATASET_NAME_LEN];
990 } dmu_objset_stats_t;
991 
992 /*
993  * Get stats on a dataset.
994  */
995 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
996 
997 /*
998  * Add entries to the nvlist for all the objset's properties.  See
999  * zfs_prop_table[] and zfs(1m) for details on the properties.
1000  */
1001 void dmu_objset_stats(objset_t *os, struct nvlist *nv);
1002 
1003 /*
1004  * Get the space usage statistics for statvfs().
1005  *
1006  * refdbytes is the amount of space "referenced" by this objset.
1007  * availbytes is the amount of space available to this objset, taking
1008  * into account quotas & reservations, assuming that no other objsets
1009  * use the space first.  These values correspond to the 'referenced' and
1010  * 'available' properties, described in the zfs(1m) manpage.
1011  *
1012  * usedobjs and availobjs are the number of objects currently allocated,
1013  * and available.
1014  */
1015 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
1016     uint64_t *usedobjsp, uint64_t *availobjsp);
1017 
1018 /*
1019  * The fsid_guid is a 56-bit ID that can change to avoid collisions.
1020  * (Contrast with the ds_guid which is a 64-bit ID that will never
1021  * change, so there is a small probability that it will collide.)
1022  */
1023 uint64_t dmu_objset_fsid_guid(objset_t *os);
1024 
1025 /*
1026  * Get the [cm]time for an objset's snapshot dir
1027  */
1028 inode_timespec_t dmu_objset_snap_cmtime(objset_t *os);
1029 
1030 int dmu_objset_is_snapshot(objset_t *os);
1031 
1032 extern struct spa *dmu_objset_spa(objset_t *os);
1033 extern struct zilog *dmu_objset_zil(objset_t *os);
1034 extern struct dsl_pool *dmu_objset_pool(objset_t *os);
1035 extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
1036 extern void dmu_objset_name(objset_t *os, char *buf);
1037 extern dmu_objset_type_t dmu_objset_type(objset_t *os);
1038 extern uint64_t dmu_objset_id(objset_t *os);
1039 extern uint64_t dmu_objset_dnodesize(objset_t *os);
1040 extern zfs_sync_type_t dmu_objset_syncprop(objset_t *os);
1041 extern zfs_logbias_op_t dmu_objset_logbias(objset_t *os);
1042 extern int dmu_objset_blksize(objset_t *os);
1043 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
1044     uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
1045 extern int dmu_snapshot_lookup(objset_t *os, const char *name, uint64_t *val);
1046 extern int dmu_snapshot_realname(objset_t *os, const char *name, char *real,
1047     int maxlen, boolean_t *conflict);
1048 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
1049     uint64_t *idp, uint64_t *offp);
1050 
1051 typedef struct zfs_file_info {
1052 	uint64_t zfi_user;
1053 	uint64_t zfi_group;
1054 	uint64_t zfi_project;
1055 	uint64_t zfi_generation;
1056 } zfs_file_info_t;
1057 
1058 typedef int file_info_cb_t(dmu_object_type_t bonustype, const void *data,
1059     struct zfs_file_info *zoi);
1060 extern void dmu_objset_register_type(dmu_objset_type_t ost,
1061     file_info_cb_t *cb);
1062 extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
1063 extern void *dmu_objset_get_user(objset_t *os);
1064 
1065 /*
1066  * Return the txg number for the given assigned transaction.
1067  */
1068 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
1069 
1070 /*
1071  * Synchronous write.
1072  * If a parent zio is provided this function initiates a write on the
1073  * provided buffer as a child of the parent zio.
1074  * In the absence of a parent zio, the write is completed synchronously.
1075  * At write completion, blk is filled with the bp of the written block.
1076  * Note that while the data covered by this function will be on stable
1077  * storage when the write completes this new data does not become a
1078  * permanent part of the file until the associated transaction commits.
1079  */
1080 
1081 /*
1082  * {zfs,zvol,ztest}_get_done() args
1083  */
1084 typedef struct zgd {
1085 	struct lwb	*zgd_lwb;
1086 	struct blkptr	*zgd_bp;
1087 	dmu_buf_t	*zgd_db;
1088 	struct zfs_locked_range *zgd_lr;
1089 	void		*zgd_private;
1090 } zgd_t;
1091 
1092 typedef void dmu_sync_cb_t(zgd_t *arg, int error);
1093 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd);
1094 
1095 /*
1096  * Find the next hole or data block in file starting at *off
1097  * Return found offset in *off. Return ESRCH for end of file.
1098  */
1099 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
1100     uint64_t *off);
1101 
1102 int dmu_read_l0_bps(objset_t *os, uint64_t object, uint64_t offset,
1103     uint64_t length, struct blkptr *bps, size_t *nbpsp);
1104 int dmu_brt_clone(objset_t *os, uint64_t object, uint64_t offset,
1105     uint64_t length, dmu_tx_t *tx, const struct blkptr *bps, size_t nbps);
1106 
1107 /*
1108  * Initial setup and final teardown.
1109  */
1110 extern void dmu_init(void);
1111 extern void dmu_fini(void);
1112 
1113 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
1114     uint64_t object, uint64_t offset, int len);
1115 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
1116     dmu_traverse_cb_t cb, void *arg);
1117 
1118 int dmu_diff(const char *tosnap_name, const char *fromsnap_name,
1119     zfs_file_t *fp, offset_t *offp);
1120 
1121 /* CRC64 table */
1122 #define	ZFS_CRC64_POLY	0xC96C5795D7870F42ULL	/* ECMA-182, reflected form */
1123 extern uint64_t zfs_crc64_table[256];
1124 
1125 extern uint_t dmu_prefetch_max;
1126 
1127 #ifdef	__cplusplus
1128 }
1129 #endif
1130 
1131 #endif	/* _SYS_DMU_H */
1132