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 */ 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_WAITED, 224 } txg_how_t; 225 226 void byteswap_uint64_array(void *buf, size_t size); 227 void byteswap_uint32_array(void *buf, size_t size); 228 void byteswap_uint16_array(void *buf, size_t size); 229 void byteswap_uint8_array(void *buf, size_t size); 230 void zap_byteswap(void *buf, size_t size); 231 void zfs_oldacl_byteswap(void *buf, size_t size); 232 void zfs_acl_byteswap(void *buf, size_t size); 233 void zfs_znode_byteswap(void *buf, size_t size); 234 235 #define DS_FIND_SNAPSHOTS (1<<0) 236 #define DS_FIND_CHILDREN (1<<1) 237 238 /* 239 * The maximum number of bytes that can be accessed as part of one 240 * operation, including metadata. 241 */ 242 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 243 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */ 244 245 #define DMU_USERUSED_OBJECT (-1ULL) 246 #define DMU_GROUPUSED_OBJECT (-2ULL) 247 #define DMU_DEADLIST_OBJECT (-3ULL) 248 249 /* 250 * artificial blkids for bonus buffer and spill blocks 251 */ 252 #define DMU_BONUS_BLKID (-1ULL) 253 #define DMU_SPILL_BLKID (-2ULL) 254 /* 255 * Public routines to create, destroy, open, and close objsets. 256 */ 257 int dmu_objset_hold(const char *name, void *tag, objset_t **osp); 258 int dmu_objset_own(const char *name, dmu_objset_type_t type, 259 boolean_t readonly, void *tag, objset_t **osp); 260 void dmu_objset_rele(objset_t *os, void *tag); 261 void dmu_objset_disown(objset_t *os, void *tag); 262 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp); 263 264 void dmu_objset_evict_dbufs(objset_t *os); 265 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags, 266 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg); 267 int dmu_objset_clone(const char *name, const char *origin); 268 int dsl_destroy_snapshots_nvl(struct nvlist *snaps, boolean_t defer, 269 struct nvlist *errlist); 270 int dmu_objset_snapshot_one(const char *fsname, const char *snapname); 271 int dmu_objset_snapshot_tmp(const char *, const char *, int); 272 int dmu_objset_find(char *name, int func(const char *, void *), void *arg, 273 int flags); 274 void dmu_objset_byteswap(void *buf, size_t size); 275 int dsl_dataset_rename_snapshot(const char *fsname, 276 const char *oldsnapname, const char *newsnapname, boolean_t recursive); 277 278 typedef struct dmu_buf { 279 uint64_t db_object; /* object that this buffer is part of */ 280 uint64_t db_offset; /* byte offset in this object */ 281 uint64_t db_size; /* size of buffer in bytes */ 282 void *db_data; /* data in buffer */ 283 } dmu_buf_t; 284 285 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 286 287 /* 288 * The names of zap entries in the DIRECTORY_OBJECT of the MOS. 289 */ 290 #define DMU_POOL_DIRECTORY_OBJECT 1 291 #define DMU_POOL_CONFIG "config" 292 #define DMU_POOL_FEATURES_FOR_WRITE "features_for_write" 293 #define DMU_POOL_FEATURES_FOR_READ "features_for_read" 294 #define DMU_POOL_FEATURE_DESCRIPTIONS "feature_descriptions" 295 #define DMU_POOL_ROOT_DATASET "root_dataset" 296 #define DMU_POOL_SYNC_BPOBJ "sync_bplist" 297 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 298 #define DMU_POOL_ERRLOG_LAST "errlog_last" 299 #define DMU_POOL_SPARES "spares" 300 #define DMU_POOL_DEFLATE "deflate" 301 #define DMU_POOL_HISTORY "history" 302 #define DMU_POOL_PROPS "pool_props" 303 #define DMU_POOL_L2CACHE "l2cache" 304 #define DMU_POOL_TMP_USERREFS "tmp_userrefs" 305 #define DMU_POOL_DDT "DDT-%s-%s-%s" 306 #define DMU_POOL_DDT_STATS "DDT-statistics" 307 #define DMU_POOL_CREATION_VERSION "creation_version" 308 #define DMU_POOL_SCAN "scan" 309 #define DMU_POOL_FREE_BPOBJ "free_bpobj" 310 #define DMU_POOL_BPTREE_OBJ "bptree_obj" 311 #define DMU_POOL_EMPTY_BPOBJ "empty_bpobj" 312 313 /* 314 * Allocate an object from this objset. The range of object numbers 315 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 316 * 317 * The transaction must be assigned to a txg. The newly allocated 318 * object will be "held" in the transaction (ie. you can modify the 319 * newly allocated object in this transaction). 320 * 321 * dmu_object_alloc() chooses an object and returns it in *objectp. 322 * 323 * dmu_object_claim() allocates a specific object number. If that 324 * number is already allocated, it fails and returns EEXIST. 325 * 326 * Return 0 on success, or ENOSPC or EEXIST as specified above. 327 */ 328 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot, 329 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 330 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot, 331 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 332 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 333 int blocksize, dmu_object_type_t bonustype, int bonuslen); 334 335 /* 336 * Free an object from this objset. 337 * 338 * The object's data will be freed as well (ie. you don't need to call 339 * dmu_free(object, 0, -1, tx)). 340 * 341 * The object need not be held in the transaction. 342 * 343 * If there are any holds on this object's buffers (via dmu_buf_hold()), 344 * or tx holds on the object (via dmu_tx_hold_object()), you can not 345 * free it; it fails and returns EBUSY. 346 * 347 * If the object is not allocated, it fails and returns ENOENT. 348 * 349 * Return 0 on success, or EBUSY or ENOENT as specified above. 350 */ 351 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 352 353 /* 354 * Find the next allocated or free object. 355 * 356 * The objectp parameter is in-out. It will be updated to be the next 357 * object which is allocated. Ignore objects which have not been 358 * modified since txg. 359 * 360 * XXX Can only be called on a objset with no dirty data. 361 * 362 * Returns 0 on success, or ENOENT if there are no more objects. 363 */ 364 int dmu_object_next(objset_t *os, uint64_t *objectp, 365 boolean_t hole, uint64_t txg); 366 367 /* 368 * Set the data blocksize for an object. 369 * 370 * The object cannot have any blocks allcated beyond the first. If 371 * the first block is allocated already, the new size must be greater 372 * than the current block size. If these conditions are not met, 373 * ENOTSUP will be returned. 374 * 375 * Returns 0 on success, or EBUSY if there are any holds on the object 376 * contents, or ENOTSUP as described above. 377 */ 378 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 379 int ibs, dmu_tx_t *tx); 380 381 /* 382 * Set the checksum property on a dnode. The new checksum algorithm will 383 * apply to all newly written blocks; existing blocks will not be affected. 384 */ 385 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 386 dmu_tx_t *tx); 387 388 /* 389 * Set the compress property on a dnode. The new compression algorithm will 390 * apply to all newly written blocks; existing blocks will not be affected. 391 */ 392 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 393 dmu_tx_t *tx); 394 395 /* 396 * Decide how to write a block: checksum, compression, number of copies, etc. 397 */ 398 #define WP_NOFILL 0x1 399 #define WP_DMU_SYNC 0x2 400 #define WP_SPILL 0x4 401 402 void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp, 403 struct zio_prop *zp); 404 /* 405 * The bonus data is accessed more or less like a regular buffer. 406 * You must dmu_bonus_hold() to get the buffer, which will give you a 407 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 408 * data. As with any normal buffer, you must call dmu_buf_read() to 409 * read db_data, dmu_buf_will_dirty() before modifying it, and the 410 * object must be held in an assigned transaction before calling 411 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 412 * buffer as well. You must release your hold with dmu_buf_rele(). 413 * 414 * Returns ENOENT, EIO, or 0. 415 */ 416 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 417 int dmu_bonus_max(void); 418 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *); 419 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *); 420 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *); 421 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *); 422 423 /* 424 * Special spill buffer support used by "SA" framework 425 */ 426 427 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 428 int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags, 429 void *tag, dmu_buf_t **dbp); 430 int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 431 432 /* 433 * Obtain the DMU buffer from the specified object which contains the 434 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 435 * that it will remain in memory. You must release the hold with 436 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 437 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 438 * 439 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 440 * on the returned buffer before reading or writing the buffer's 441 * db_data. The comments for those routines describe what particular 442 * operations are valid after calling them. 443 * 444 * The object number must be a valid, allocated object number. 445 */ 446 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 447 void *tag, dmu_buf_t **, int flags); 448 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 449 void dmu_buf_rele(dmu_buf_t *db, void *tag); 450 uint64_t dmu_buf_refcount(dmu_buf_t *db); 451 452 /* 453 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 454 * range of an object. A pointer to an array of dmu_buf_t*'s is 455 * returned (in *dbpp). 456 * 457 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 458 * frees the array. The hold on the array of buffers MUST be released 459 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 460 * individually with dmu_buf_rele. 461 */ 462 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 463 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 464 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 465 466 /* 467 * Returns NULL on success, or the existing user ptr if it's already 468 * been set. 469 * 470 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 471 * 472 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 473 * will be set to db->db_data when you are allowed to access it. Note 474 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 475 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 476 * *user_data_ptr_ptr will be set to the new value when it changes. 477 * 478 * If non-NULL, pageout func will be called when this buffer is being 479 * excised from the cache, so that you can clean up the data structure 480 * pointed to by user_ptr. 481 * 482 * dmu_evict_user() will call the pageout func for all buffers in a 483 * objset with a given pageout func. 484 */ 485 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 486 dmu_buf_evict_func_t *pageout_func); 487 /* 488 * set_user_ie is the same as set_user, but request immediate eviction 489 * when hold count goes to zero. 490 */ 491 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 492 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 493 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 494 void *user_ptr, void *user_data_ptr_ptr, 495 dmu_buf_evict_func_t *pageout_func); 496 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 497 498 /* 499 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 500 */ 501 void *dmu_buf_get_user(dmu_buf_t *db); 502 503 /* 504 * Returns the blkptr associated with this dbuf, or NULL if not set. 505 */ 506 struct blkptr *dmu_buf_get_blkptr(dmu_buf_t *db); 507 508 /* 509 * Indicate that you are going to modify the buffer's data (db_data). 510 * 511 * The transaction (tx) must be assigned to a txg (ie. you've called 512 * dmu_tx_assign()). The buffer's object must be held in the tx 513 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 514 */ 515 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 516 517 /* 518 * Tells if the given dbuf is freeable. 519 */ 520 boolean_t dmu_buf_freeable(dmu_buf_t *); 521 522 /* 523 * You must create a transaction, then hold the objects which you will 524 * (or might) modify as part of this transaction. Then you must assign 525 * the transaction to a transaction group. Once the transaction has 526 * been assigned, you can modify buffers which belong to held objects as 527 * part of this transaction. You can't modify buffers before the 528 * transaction has been assigned; you can't modify buffers which don't 529 * belong to objects which this transaction holds; you can't hold 530 * objects once the transaction has been assigned. You may hold an 531 * object which you are going to free (with dmu_object_free()), but you 532 * don't have to. 533 * 534 * You can abort the transaction before it has been assigned. 535 * 536 * Note that you may hold buffers (with dmu_buf_hold) at any time, 537 * regardless of transaction state. 538 */ 539 540 #define DMU_NEW_OBJECT (-1ULL) 541 #define DMU_OBJECT_END (-1ULL) 542 543 dmu_tx_t *dmu_tx_create(objset_t *os); 544 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 545 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 546 uint64_t len); 547 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name); 548 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 549 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object); 550 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow); 551 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size); 552 void dmu_tx_abort(dmu_tx_t *tx); 553 int dmu_tx_assign(dmu_tx_t *tx, enum txg_how txg_how); 554 void dmu_tx_wait(dmu_tx_t *tx); 555 void dmu_tx_commit(dmu_tx_t *tx); 556 557 /* 558 * To register a commit callback, dmu_tx_callback_register() must be called. 559 * 560 * dcb_data is a pointer to caller private data that is passed on as a 561 * callback parameter. The caller is responsible for properly allocating and 562 * freeing it. 563 * 564 * When registering a callback, the transaction must be already created, but 565 * it cannot be committed or aborted. It can be assigned to a txg or not. 566 * 567 * The callback will be called after the transaction has been safely written 568 * to stable storage and will also be called if the dmu_tx is aborted. 569 * If there is any error which prevents the transaction from being committed to 570 * disk, the callback will be called with a value of error != 0. 571 */ 572 typedef void dmu_tx_callback_func_t(void *dcb_data, int error); 573 574 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func, 575 void *dcb_data); 576 577 /* 578 * Free up the data blocks for a defined range of a file. If size is 579 * -1, the range from offset to end-of-file is freed. 580 */ 581 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 582 uint64_t size, dmu_tx_t *tx); 583 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset, 584 uint64_t size); 585 int dmu_free_long_object(objset_t *os, uint64_t object); 586 587 /* 588 * Convenience functions. 589 * 590 * Canfail routines will return 0 on success, or an errno if there is a 591 * nonrecoverable I/O error. 592 */ 593 #define DMU_READ_PREFETCH 0 /* prefetch */ 594 #define DMU_READ_NO_PREFETCH 1 /* don't prefetch */ 595 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 596 void *buf, uint32_t flags); 597 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 598 const void *buf, dmu_tx_t *tx); 599 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 600 dmu_tx_t *tx); 601 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size); 602 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size, 603 dmu_tx_t *tx); 604 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size, 605 dmu_tx_t *tx); 606 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, 607 uint64_t size, struct page *pp, dmu_tx_t *tx); 608 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size); 609 void dmu_return_arcbuf(struct arc_buf *buf); 610 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf, 611 dmu_tx_t *tx); 612 int dmu_xuio_init(struct xuio *uio, int niov); 613 void dmu_xuio_fini(struct xuio *uio); 614 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off, 615 size_t n); 616 int dmu_xuio_cnt(struct xuio *uio); 617 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i); 618 void dmu_xuio_clear(struct xuio *uio, int i); 619 void xuio_stat_wbuf_copied(); 620 void xuio_stat_wbuf_nocopy(); 621 622 extern int zfs_prefetch_disable; 623 624 /* 625 * Asynchronously try to read in the data. 626 */ 627 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 628 uint64_t len); 629 630 typedef struct dmu_object_info { 631 /* All sizes are in bytes unless otherwise indicated. */ 632 uint32_t doi_data_block_size; 633 uint32_t doi_metadata_block_size; 634 dmu_object_type_t doi_type; 635 dmu_object_type_t doi_bonus_type; 636 uint64_t doi_bonus_size; 637 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 638 uint8_t doi_checksum; 639 uint8_t doi_compress; 640 uint8_t doi_pad[5]; 641 uint64_t doi_physical_blocks_512; /* data + metadata, 512b blks */ 642 uint64_t doi_max_offset; 643 uint64_t doi_fill_count; /* number of non-empty blocks */ 644 } dmu_object_info_t; 645 646 typedef void arc_byteswap_func_t(void *buf, size_t size); 647 648 typedef struct dmu_object_type_info { 649 dmu_object_byteswap_t ot_byteswap; 650 boolean_t ot_metadata; 651 char *ot_name; 652 } dmu_object_type_info_t; 653 654 typedef struct dmu_object_byteswap_info { 655 arc_byteswap_func_t *ob_func; 656 char *ob_name; 657 } dmu_object_byteswap_info_t; 658 659 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 660 extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS]; 661 662 /* 663 * Get information on a DMU object. 664 * 665 * Return 0 on success or ENOENT if object is not allocated. 666 * 667 * If doi is NULL, just indicates whether the object exists. 668 */ 669 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 670 /* Like dmu_object_info, but faster if you have a held dnode in hand. */ 671 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 672 /* Like dmu_object_info, but faster if you have a held dbuf in hand. */ 673 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 674 /* 675 * Like dmu_object_info_from_db, but faster still when you only care about 676 * the size. This is specifically optimized for zfs_getattr(). 677 */ 678 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 679 u_longlong_t *nblk512); 680 681 typedef struct dmu_objset_stats { 682 uint64_t dds_num_clones; /* number of clones of this */ 683 uint64_t dds_creation_txg; 684 uint64_t dds_guid; 685 dmu_objset_type_t dds_type; 686 uint8_t dds_is_snapshot; 687 uint8_t dds_inconsistent; 688 char dds_origin[MAXNAMELEN]; 689 } dmu_objset_stats_t; 690 691 /* 692 * Get stats on a dataset. 693 */ 694 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat); 695 696 /* 697 * Add entries to the nvlist for all the objset's properties. See 698 * zfs_prop_table[] and zfs(1m) for details on the properties. 699 */ 700 void dmu_objset_stats(objset_t *os, struct nvlist *nv); 701 702 /* 703 * Get the space usage statistics for statvfs(). 704 * 705 * refdbytes is the amount of space "referenced" by this objset. 706 * availbytes is the amount of space available to this objset, taking 707 * into account quotas & reservations, assuming that no other objsets 708 * use the space first. These values correspond to the 'referenced' and 709 * 'available' properties, described in the zfs(1m) manpage. 710 * 711 * usedobjs and availobjs are the number of objects currently allocated, 712 * and available. 713 */ 714 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp, 715 uint64_t *usedobjsp, uint64_t *availobjsp); 716 717 /* 718 * The fsid_guid is a 56-bit ID that can change to avoid collisions. 719 * (Contrast with the ds_guid which is a 64-bit ID that will never 720 * change, so there is a small probability that it will collide.) 721 */ 722 uint64_t dmu_objset_fsid_guid(objset_t *os); 723 724 /* 725 * Get the [cm]time for an objset's snapshot dir 726 */ 727 timestruc_t dmu_objset_snap_cmtime(objset_t *os); 728 729 int dmu_objset_is_snapshot(objset_t *os); 730 731 extern struct spa *dmu_objset_spa(objset_t *os); 732 extern struct zilog *dmu_objset_zil(objset_t *os); 733 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 734 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 735 extern void dmu_objset_name(objset_t *os, char *buf); 736 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 737 extern uint64_t dmu_objset_id(objset_t *os); 738 extern uint64_t dmu_objset_syncprop(objset_t *os); 739 extern uint64_t dmu_objset_logbias(objset_t *os); 740 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 741 uint64_t *id, uint64_t *offp, boolean_t *case_conflict); 742 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real, 743 int maxlen, boolean_t *conflict); 744 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 745 uint64_t *idp, uint64_t *offp); 746 747 typedef int objset_used_cb_t(dmu_object_type_t bonustype, 748 void *bonus, uint64_t *userp, uint64_t *groupp); 749 extern void dmu_objset_register_type(dmu_objset_type_t ost, 750 objset_used_cb_t *cb); 751 extern void dmu_objset_set_user(objset_t *os, void *user_ptr); 752 extern void *dmu_objset_get_user(objset_t *os); 753 754 /* 755 * Return the txg number for the given assigned transaction. 756 */ 757 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 758 759 /* 760 * Synchronous write. 761 * If a parent zio is provided this function initiates a write on the 762 * provided buffer as a child of the parent zio. 763 * In the absence of a parent zio, the write is completed synchronously. 764 * At write completion, blk is filled with the bp of the written block. 765 * Note that while the data covered by this function will be on stable 766 * storage when the write completes this new data does not become a 767 * permanent part of the file until the associated transaction commits. 768 */ 769 770 /* 771 * {zfs,zvol,ztest}_get_done() args 772 */ 773 typedef struct zgd { 774 struct zilog *zgd_zilog; 775 struct blkptr *zgd_bp; 776 dmu_buf_t *zgd_db; 777 struct rl *zgd_rl; 778 void *zgd_private; 779 } zgd_t; 780 781 typedef void dmu_sync_cb_t(zgd_t *arg, int error); 782 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd); 783 784 /* 785 * Find the next hole or data block in file starting at *off 786 * Return found offset in *off. Return ESRCH for end of file. 787 */ 788 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 789 uint64_t *off); 790 791 /* 792 * Initial setup and final teardown. 793 */ 794 extern void dmu_init(void); 795 extern void dmu_fini(void); 796 797 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 798 uint64_t object, uint64_t offset, int len); 799 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 800 dmu_traverse_cb_t cb, void *arg); 801 802 int dmu_diff(const char *tosnap_name, const char *fromsnap_name, 803 struct vnode *vp, offset_t *offp); 804 805 /* CRC64 table */ 806 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 807 extern uint64_t zfs_crc64_table[256]; 808 809 #ifdef __cplusplus 810 } 811 #endif 812 813 #endif /* _SYS_DMU_H */ 814