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) 2013 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 #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_WAITED, 225 } txg_how_t; 226 227 void byteswap_uint64_array(void *buf, size_t size); 228 void byteswap_uint32_array(void *buf, size_t size); 229 void byteswap_uint16_array(void *buf, size_t size); 230 void byteswap_uint8_array(void *buf, size_t size); 231 void zap_byteswap(void *buf, size_t size); 232 void zfs_oldacl_byteswap(void *buf, size_t size); 233 void zfs_acl_byteswap(void *buf, size_t size); 234 void zfs_znode_byteswap(void *buf, size_t size); 235 236 #define DS_FIND_SNAPSHOTS (1<<0) 237 #define DS_FIND_CHILDREN (1<<1) 238 239 /* 240 * The maximum number of bytes that can be accessed as part of one 241 * operation, including metadata. 242 */ 243 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 244 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */ 245 246 #define DMU_USERUSED_OBJECT (-1ULL) 247 #define DMU_GROUPUSED_OBJECT (-2ULL) 248 #define DMU_DEADLIST_OBJECT (-3ULL) 249 250 /* 251 * artificial blkids for bonus buffer and spill blocks 252 */ 253 #define DMU_BONUS_BLKID (-1ULL) 254 #define DMU_SPILL_BLKID (-2ULL) 255 /* 256 * Public routines to create, destroy, open, and close objsets. 257 */ 258 int dmu_objset_hold(const char *name, void *tag, objset_t **osp); 259 int dmu_objset_own(const char *name, dmu_objset_type_t type, 260 boolean_t readonly, void *tag, objset_t **osp); 261 void dmu_objset_rele(objset_t *os, void *tag); 262 void dmu_objset_disown(objset_t *os, void *tag); 263 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp); 264 265 void dmu_objset_evict_dbufs(objset_t *os); 266 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags, 267 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg); 268 int dmu_objset_clone(const char *name, const char *origin); 269 int dsl_destroy_snapshots_nvl(struct nvlist *snaps, boolean_t defer, 270 struct nvlist *errlist); 271 int dmu_objset_snapshot_one(const char *fsname, const char *snapname); 272 int dmu_objset_snapshot_tmp(const char *, const char *, int); 273 int dmu_objset_find(char *name, int func(const char *, void *), void *arg, 274 int flags); 275 void dmu_objset_byteswap(void *buf, size_t size); 276 int dsl_dataset_rename_snapshot(const char *fsname, 277 const char *oldsnapname, const char *newsnapname, boolean_t recursive); 278 279 typedef struct dmu_buf { 280 uint64_t db_object; /* object that this buffer is part of */ 281 uint64_t db_offset; /* byte offset in this object */ 282 uint64_t db_size; /* size of buffer in bytes */ 283 void *db_data; /* data in buffer */ 284 } dmu_buf_t; 285 286 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 287 288 /* 289 * The names of zap entries in the DIRECTORY_OBJECT of the MOS. 290 */ 291 #define DMU_POOL_DIRECTORY_OBJECT 1 292 #define DMU_POOL_CONFIG "config" 293 #define DMU_POOL_FEATURES_FOR_WRITE "features_for_write" 294 #define DMU_POOL_FEATURES_FOR_READ "features_for_read" 295 #define DMU_POOL_FEATURE_DESCRIPTIONS "feature_descriptions" 296 #define DMU_POOL_FEATURE_ENABLED_TXG "feature_enabled_txg" 297 #define DMU_POOL_ROOT_DATASET "root_dataset" 298 #define DMU_POOL_SYNC_BPOBJ "sync_bplist" 299 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 300 #define DMU_POOL_ERRLOG_LAST "errlog_last" 301 #define DMU_POOL_SPARES "spares" 302 #define DMU_POOL_DEFLATE "deflate" 303 #define DMU_POOL_HISTORY "history" 304 #define DMU_POOL_PROPS "pool_props" 305 #define DMU_POOL_L2CACHE "l2cache" 306 #define DMU_POOL_TMP_USERREFS "tmp_userrefs" 307 #define DMU_POOL_DDT "DDT-%s-%s-%s" 308 #define DMU_POOL_DDT_STATS "DDT-statistics" 309 #define DMU_POOL_CREATION_VERSION "creation_version" 310 #define DMU_POOL_SCAN "scan" 311 #define DMU_POOL_FREE_BPOBJ "free_bpobj" 312 #define DMU_POOL_BPTREE_OBJ "bptree_obj" 313 #define DMU_POOL_EMPTY_BPOBJ "empty_bpobj" 314 315 /* 316 * Allocate an object from this objset. The range of object numbers 317 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 318 * 319 * The transaction must be assigned to a txg. The newly allocated 320 * object will be "held" in the transaction (ie. you can modify the 321 * newly allocated object in this transaction). 322 * 323 * dmu_object_alloc() chooses an object and returns it in *objectp. 324 * 325 * dmu_object_claim() allocates a specific object number. If that 326 * number is already allocated, it fails and returns EEXIST. 327 * 328 * Return 0 on success, or ENOSPC or EEXIST as specified above. 329 */ 330 uint64_t dmu_object_alloc(objset_t *os, 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_claim(objset_t *os, uint64_t object, dmu_object_type_t ot, 333 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 334 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 335 int blocksize, dmu_object_type_t bonustype, int bonuslen); 336 337 /* 338 * Free an object from this objset. 339 * 340 * The object's data will be freed as well (ie. you don't need to call 341 * dmu_free(object, 0, -1, tx)). 342 * 343 * The object need not be held in the transaction. 344 * 345 * If there are any holds on this object's buffers (via dmu_buf_hold()), 346 * or tx holds on the object (via dmu_tx_hold_object()), you can not 347 * free it; it fails and returns EBUSY. 348 * 349 * If the object is not allocated, it fails and returns ENOENT. 350 * 351 * Return 0 on success, or EBUSY or ENOENT as specified above. 352 */ 353 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 354 355 /* 356 * Find the next allocated or free object. 357 * 358 * The objectp parameter is in-out. It will be updated to be the next 359 * object which is allocated. Ignore objects which have not been 360 * modified since txg. 361 * 362 * XXX Can only be called on a objset with no dirty data. 363 * 364 * Returns 0 on success, or ENOENT if there are no more objects. 365 */ 366 int dmu_object_next(objset_t *os, uint64_t *objectp, 367 boolean_t hole, uint64_t txg); 368 369 /* 370 * Set the data blocksize for an object. 371 * 372 * The object cannot have any blocks allcated beyond the first. If 373 * the first block is allocated already, the new size must be greater 374 * than the current block size. If these conditions are not met, 375 * ENOTSUP will be returned. 376 * 377 * Returns 0 on success, or EBUSY if there are any holds on the object 378 * contents, or ENOTSUP as described above. 379 */ 380 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 381 int ibs, dmu_tx_t *tx); 382 383 /* 384 * Set the checksum property on a dnode. The new checksum algorithm will 385 * apply to all newly written blocks; existing blocks will not be affected. 386 */ 387 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 388 dmu_tx_t *tx); 389 390 /* 391 * Set the compress property on a dnode. The new compression algorithm will 392 * apply to all newly written blocks; existing blocks will not be affected. 393 */ 394 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 395 dmu_tx_t *tx); 396 397 /* 398 * Decide how to write a block: checksum, compression, number of copies, etc. 399 */ 400 #define WP_NOFILL 0x1 401 #define WP_DMU_SYNC 0x2 402 #define WP_SPILL 0x4 403 404 void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp, 405 struct zio_prop *zp); 406 /* 407 * The bonus data is accessed more or less like a regular buffer. 408 * You must dmu_bonus_hold() to get the buffer, which will give you a 409 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 410 * data. As with any normal buffer, you must call dmu_buf_read() to 411 * read db_data, dmu_buf_will_dirty() before modifying it, and the 412 * object must be held in an assigned transaction before calling 413 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 414 * buffer as well. You must release your hold with dmu_buf_rele(). 415 * 416 * Returns ENOENT, EIO, or 0. 417 */ 418 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 419 int dmu_bonus_max(void); 420 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *); 421 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *); 422 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *); 423 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *); 424 425 /* 426 * Special spill buffer support used by "SA" framework 427 */ 428 429 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 430 int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags, 431 void *tag, dmu_buf_t **dbp); 432 int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 433 434 /* 435 * Obtain the DMU buffer from the specified object which contains the 436 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 437 * that it will remain in memory. You must release the hold with 438 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 439 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 440 * 441 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 442 * on the returned buffer before reading or writing the buffer's 443 * db_data. The comments for those routines describe what particular 444 * operations are valid after calling them. 445 * 446 * The object number must be a valid, allocated object number. 447 */ 448 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 449 void *tag, dmu_buf_t **, int flags); 450 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 451 void dmu_buf_rele(dmu_buf_t *db, void *tag); 452 uint64_t dmu_buf_refcount(dmu_buf_t *db); 453 454 /* 455 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 456 * range of an object. A pointer to an array of dmu_buf_t*'s is 457 * returned (in *dbpp). 458 * 459 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 460 * frees the array. The hold on the array of buffers MUST be released 461 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 462 * individually with dmu_buf_rele. 463 */ 464 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 465 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 466 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 467 468 /* 469 * Returns NULL on success, or the existing user ptr if it's already 470 * been set. 471 * 472 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 473 * 474 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 475 * will be set to db->db_data when you are allowed to access it. Note 476 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 477 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 478 * *user_data_ptr_ptr will be set to the new value when it changes. 479 * 480 * If non-NULL, pageout func will be called when this buffer is being 481 * excised from the cache, so that you can clean up the data structure 482 * pointed to by user_ptr. 483 * 484 * dmu_evict_user() will call the pageout func for all buffers in a 485 * objset with a given pageout func. 486 */ 487 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 488 dmu_buf_evict_func_t *pageout_func); 489 /* 490 * set_user_ie is the same as set_user, but request immediate eviction 491 * when hold count goes to zero. 492 */ 493 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 494 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 495 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 496 void *user_ptr, void *user_data_ptr_ptr, 497 dmu_buf_evict_func_t *pageout_func); 498 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 499 500 /* 501 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 502 */ 503 void *dmu_buf_get_user(dmu_buf_t *db); 504 505 /* 506 * Returns the blkptr associated with this dbuf, or NULL if not set. 507 */ 508 struct blkptr *dmu_buf_get_blkptr(dmu_buf_t *db); 509 510 /* 511 * Indicate that you are going to modify the buffer's data (db_data). 512 * 513 * The transaction (tx) must be assigned to a txg (ie. you've called 514 * dmu_tx_assign()). The buffer's object must be held in the tx 515 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 516 */ 517 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 518 519 /* 520 * Tells if the given dbuf is freeable. 521 */ 522 boolean_t dmu_buf_freeable(dmu_buf_t *); 523 524 /* 525 * You must create a transaction, then hold the objects which you will 526 * (or might) modify as part of this transaction. Then you must assign 527 * the transaction to a transaction group. Once the transaction has 528 * been assigned, you can modify buffers which belong to held objects as 529 * part of this transaction. You can't modify buffers before the 530 * transaction has been assigned; you can't modify buffers which don't 531 * belong to objects which this transaction holds; you can't hold 532 * objects once the transaction has been assigned. You may hold an 533 * object which you are going to free (with dmu_object_free()), but you 534 * don't have to. 535 * 536 * You can abort the transaction before it has been assigned. 537 * 538 * Note that you may hold buffers (with dmu_buf_hold) at any time, 539 * regardless of transaction state. 540 */ 541 542 #define DMU_NEW_OBJECT (-1ULL) 543 #define DMU_OBJECT_END (-1ULL) 544 545 dmu_tx_t *dmu_tx_create(objset_t *os); 546 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 547 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 548 uint64_t len); 549 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name); 550 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 551 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object); 552 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow); 553 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size); 554 void dmu_tx_abort(dmu_tx_t *tx); 555 int dmu_tx_assign(dmu_tx_t *tx, enum txg_how txg_how); 556 void dmu_tx_wait(dmu_tx_t *tx); 557 void dmu_tx_commit(dmu_tx_t *tx); 558 559 /* 560 * To register a commit callback, dmu_tx_callback_register() must be called. 561 * 562 * dcb_data is a pointer to caller private data that is passed on as a 563 * callback parameter. The caller is responsible for properly allocating and 564 * freeing it. 565 * 566 * When registering a callback, the transaction must be already created, but 567 * it cannot be committed or aborted. It can be assigned to a txg or not. 568 * 569 * The callback will be called after the transaction has been safely written 570 * to stable storage and will also be called if the dmu_tx is aborted. 571 * If there is any error which prevents the transaction from being committed to 572 * disk, the callback will be called with a value of error != 0. 573 */ 574 typedef void dmu_tx_callback_func_t(void *dcb_data, int error); 575 576 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func, 577 void *dcb_data); 578 579 /* 580 * Free up the data blocks for a defined range of a file. If size is 581 * -1, the range from offset to end-of-file is freed. 582 */ 583 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 584 uint64_t size, dmu_tx_t *tx); 585 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset, 586 uint64_t size); 587 int dmu_free_long_object(objset_t *os, uint64_t object); 588 589 /* 590 * Convenience functions. 591 * 592 * Canfail routines will return 0 on success, or an errno if there is a 593 * nonrecoverable I/O error. 594 */ 595 #define DMU_READ_PREFETCH 0 /* prefetch */ 596 #define DMU_READ_NO_PREFETCH 1 /* don't prefetch */ 597 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 598 void *buf, uint32_t flags); 599 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 600 const void *buf, dmu_tx_t *tx); 601 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 602 dmu_tx_t *tx); 603 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size); 604 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size, 605 dmu_tx_t *tx); 606 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size, 607 dmu_tx_t *tx); 608 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, 609 uint64_t size, struct page *pp, dmu_tx_t *tx); 610 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size); 611 void dmu_return_arcbuf(struct arc_buf *buf); 612 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf, 613 dmu_tx_t *tx); 614 int dmu_xuio_init(struct xuio *uio, int niov); 615 void dmu_xuio_fini(struct xuio *uio); 616 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off, 617 size_t n); 618 int dmu_xuio_cnt(struct xuio *uio); 619 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i); 620 void dmu_xuio_clear(struct xuio *uio, int i); 621 void xuio_stat_wbuf_copied(); 622 void xuio_stat_wbuf_nocopy(); 623 624 extern int zfs_prefetch_disable; 625 626 /* 627 * Asynchronously try to read in the data. 628 */ 629 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 630 uint64_t len); 631 632 typedef struct dmu_object_info { 633 /* All sizes are in bytes unless otherwise indicated. */ 634 uint32_t doi_data_block_size; 635 uint32_t doi_metadata_block_size; 636 dmu_object_type_t doi_type; 637 dmu_object_type_t doi_bonus_type; 638 uint64_t doi_bonus_size; 639 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 640 uint8_t doi_checksum; 641 uint8_t doi_compress; 642 uint8_t doi_pad[5]; 643 uint64_t doi_physical_blocks_512; /* data + metadata, 512b blks */ 644 uint64_t doi_max_offset; 645 uint64_t doi_fill_count; /* number of non-empty blocks */ 646 } dmu_object_info_t; 647 648 typedef void arc_byteswap_func_t(void *buf, size_t size); 649 650 typedef struct dmu_object_type_info { 651 dmu_object_byteswap_t ot_byteswap; 652 boolean_t ot_metadata; 653 char *ot_name; 654 } dmu_object_type_info_t; 655 656 typedef struct dmu_object_byteswap_info { 657 arc_byteswap_func_t *ob_func; 658 char *ob_name; 659 } dmu_object_byteswap_info_t; 660 661 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 662 extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS]; 663 664 /* 665 * Get information on a DMU object. 666 * 667 * Return 0 on success or ENOENT if object is not allocated. 668 * 669 * If doi is NULL, just indicates whether the object exists. 670 */ 671 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 672 /* Like dmu_object_info, but faster if you have a held dnode in hand. */ 673 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 674 /* Like dmu_object_info, but faster if you have a held dbuf in hand. */ 675 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 676 /* 677 * Like dmu_object_info_from_db, but faster still when you only care about 678 * the size. This is specifically optimized for zfs_getattr(). 679 */ 680 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 681 u_longlong_t *nblk512); 682 683 typedef struct dmu_objset_stats { 684 uint64_t dds_num_clones; /* number of clones of this */ 685 uint64_t dds_creation_txg; 686 uint64_t dds_guid; 687 dmu_objset_type_t dds_type; 688 uint8_t dds_is_snapshot; 689 uint8_t dds_inconsistent; 690 char dds_origin[MAXNAMELEN]; 691 } dmu_objset_stats_t; 692 693 /* 694 * Get stats on a dataset. 695 */ 696 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat); 697 698 /* 699 * Add entries to the nvlist for all the objset's properties. See 700 * zfs_prop_table[] and zfs(1m) for details on the properties. 701 */ 702 void dmu_objset_stats(objset_t *os, struct nvlist *nv); 703 704 /* 705 * Get the space usage statistics for statvfs(). 706 * 707 * refdbytes is the amount of space "referenced" by this objset. 708 * availbytes is the amount of space available to this objset, taking 709 * into account quotas & reservations, assuming that no other objsets 710 * use the space first. These values correspond to the 'referenced' and 711 * 'available' properties, described in the zfs(1m) manpage. 712 * 713 * usedobjs and availobjs are the number of objects currently allocated, 714 * and available. 715 */ 716 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp, 717 uint64_t *usedobjsp, uint64_t *availobjsp); 718 719 /* 720 * The fsid_guid is a 56-bit ID that can change to avoid collisions. 721 * (Contrast with the ds_guid which is a 64-bit ID that will never 722 * change, so there is a small probability that it will collide.) 723 */ 724 uint64_t dmu_objset_fsid_guid(objset_t *os); 725 726 /* 727 * Get the [cm]time for an objset's snapshot dir 728 */ 729 timestruc_t dmu_objset_snap_cmtime(objset_t *os); 730 731 int dmu_objset_is_snapshot(objset_t *os); 732 733 extern struct spa *dmu_objset_spa(objset_t *os); 734 extern struct zilog *dmu_objset_zil(objset_t *os); 735 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 736 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 737 extern void dmu_objset_name(objset_t *os, char *buf); 738 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 739 extern uint64_t dmu_objset_id(objset_t *os); 740 extern uint64_t dmu_objset_syncprop(objset_t *os); 741 extern uint64_t dmu_objset_logbias(objset_t *os); 742 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 743 uint64_t *id, uint64_t *offp, boolean_t *case_conflict); 744 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real, 745 int maxlen, boolean_t *conflict); 746 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 747 uint64_t *idp, uint64_t *offp); 748 749 typedef int objset_used_cb_t(dmu_object_type_t bonustype, 750 void *bonus, uint64_t *userp, uint64_t *groupp); 751 extern void dmu_objset_register_type(dmu_objset_type_t ost, 752 objset_used_cb_t *cb); 753 extern void dmu_objset_set_user(objset_t *os, void *user_ptr); 754 extern void *dmu_objset_get_user(objset_t *os); 755 756 /* 757 * Return the txg number for the given assigned transaction. 758 */ 759 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 760 761 /* 762 * Synchronous write. 763 * If a parent zio is provided this function initiates a write on the 764 * provided buffer as a child of the parent zio. 765 * In the absence of a parent zio, the write is completed synchronously. 766 * At write completion, blk is filled with the bp of the written block. 767 * Note that while the data covered by this function will be on stable 768 * storage when the write completes this new data does not become a 769 * permanent part of the file until the associated transaction commits. 770 */ 771 772 /* 773 * {zfs,zvol,ztest}_get_done() args 774 */ 775 typedef struct zgd { 776 struct zilog *zgd_zilog; 777 struct blkptr *zgd_bp; 778 dmu_buf_t *zgd_db; 779 struct rl *zgd_rl; 780 void *zgd_private; 781 } zgd_t; 782 783 typedef void dmu_sync_cb_t(zgd_t *arg, int error); 784 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd); 785 786 /* 787 * Find the next hole or data block in file starting at *off 788 * Return found offset in *off. Return ESRCH for end of file. 789 */ 790 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 791 uint64_t *off); 792 793 /* 794 * Initial setup and final teardown. 795 */ 796 extern void dmu_init(void); 797 extern void dmu_fini(void); 798 799 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 800 uint64_t object, uint64_t offset, int len); 801 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 802 dmu_traverse_cb_t cb, void *arg); 803 804 int dmu_diff(const char *tosnap_name, const char *fromsnap_name, 805 struct vnode *vp, offset_t *offp); 806 807 /* CRC64 table */ 808 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 809 extern uint64_t zfs_crc64_table[256]; 810 811 extern int zfs_mdcomp_disable; 812 813 #ifdef __cplusplus 814 } 815 #endif 816 817 #endif /* _SYS_DMU_H */ 818