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