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 void byteswap_uint64_array(void *buf, size_t size); 221 void byteswap_uint32_array(void *buf, size_t size); 222 void byteswap_uint16_array(void *buf, size_t size); 223 void byteswap_uint8_array(void *buf, size_t size); 224 void zap_byteswap(void *buf, size_t size); 225 void zfs_oldacl_byteswap(void *buf, size_t size); 226 void zfs_acl_byteswap(void *buf, size_t size); 227 void zfs_znode_byteswap(void *buf, size_t size); 228 229 #define DS_FIND_SNAPSHOTS (1<<0) 230 #define DS_FIND_CHILDREN (1<<1) 231 232 /* 233 * The maximum number of bytes that can be accessed as part of one 234 * operation, including metadata. 235 */ 236 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 237 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */ 238 239 #define DMU_USERUSED_OBJECT (-1ULL) 240 #define DMU_GROUPUSED_OBJECT (-2ULL) 241 #define DMU_DEADLIST_OBJECT (-3ULL) 242 243 /* 244 * artificial blkids for bonus buffer and spill blocks 245 */ 246 #define DMU_BONUS_BLKID (-1ULL) 247 #define DMU_SPILL_BLKID (-2ULL) 248 /* 249 * Public routines to create, destroy, open, and close objsets. 250 */ 251 int dmu_objset_hold(const char *name, void *tag, objset_t **osp); 252 int dmu_objset_own(const char *name, dmu_objset_type_t type, 253 boolean_t readonly, void *tag, objset_t **osp); 254 void dmu_objset_rele(objset_t *os, void *tag); 255 void dmu_objset_disown(objset_t *os, void *tag); 256 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp); 257 258 int dmu_objset_evict_dbufs(objset_t *os); 259 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags, 260 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg); 261 int dmu_objset_clone(const char *name, struct dsl_dataset *clone_origin, 262 uint64_t flags); 263 int dmu_objset_destroy(const char *name, boolean_t defer); 264 int dmu_snapshots_destroy_nvl(struct nvlist *snaps, boolean_t defer, 265 struct nvlist *errlist); 266 int dmu_objset_snapshot(struct nvlist *snaps, struct nvlist *, struct nvlist *); 267 int dmu_objset_snapshot_one(const char *fsname, const char *snapname); 268 int dmu_objset_snapshot_tmp(const char *, const char *, int); 269 int dmu_objset_rename(const char *name, const char *newname, 270 boolean_t recursive); 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); 274 275 typedef struct dmu_buf { 276 uint64_t db_object; /* object that this buffer is part of */ 277 uint64_t db_offset; /* byte offset in this object */ 278 uint64_t db_size; /* size of buffer in bytes */ 279 void *db_data; /* data in buffer */ 280 } dmu_buf_t; 281 282 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 283 284 /* 285 * The names of zap entries in the DIRECTORY_OBJECT of the MOS. 286 */ 287 #define DMU_POOL_DIRECTORY_OBJECT 1 288 #define DMU_POOL_CONFIG "config" 289 #define DMU_POOL_FEATURES_FOR_WRITE "features_for_write" 290 #define DMU_POOL_FEATURES_FOR_READ "features_for_read" 291 #define DMU_POOL_FEATURE_DESCRIPTIONS "feature_descriptions" 292 #define DMU_POOL_ROOT_DATASET "root_dataset" 293 #define DMU_POOL_SYNC_BPOBJ "sync_bplist" 294 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 295 #define DMU_POOL_ERRLOG_LAST "errlog_last" 296 #define DMU_POOL_SPARES "spares" 297 #define DMU_POOL_DEFLATE "deflate" 298 #define DMU_POOL_HISTORY "history" 299 #define DMU_POOL_PROPS "pool_props" 300 #define DMU_POOL_L2CACHE "l2cache" 301 #define DMU_POOL_TMP_USERREFS "tmp_userrefs" 302 #define DMU_POOL_DDT "DDT-%s-%s-%s" 303 #define DMU_POOL_DDT_STATS "DDT-statistics" 304 #define DMU_POOL_CREATION_VERSION "creation_version" 305 #define DMU_POOL_SCAN "scan" 306 #define DMU_POOL_FREE_BPOBJ "free_bpobj" 307 #define DMU_POOL_BPTREE_OBJ "bptree_obj" 308 #define DMU_POOL_EMPTY_BPOBJ "empty_bpobj" 309 310 /* 311 * Allocate an object from this objset. The range of object numbers 312 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 313 * 314 * The transaction must be assigned to a txg. The newly allocated 315 * object will be "held" in the transaction (ie. you can modify the 316 * newly allocated object in this transaction). 317 * 318 * dmu_object_alloc() chooses an object and returns it in *objectp. 319 * 320 * dmu_object_claim() allocates a specific object number. If that 321 * number is already allocated, it fails and returns EEXIST. 322 * 323 * Return 0 on success, or ENOSPC or EEXIST as specified above. 324 */ 325 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot, 326 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 327 int dmu_object_claim(objset_t *os, uint64_t object, 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_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 330 int blocksize, dmu_object_type_t bonustype, int bonuslen); 331 332 /* 333 * Free an object from this objset. 334 * 335 * The object's data will be freed as well (ie. you don't need to call 336 * dmu_free(object, 0, -1, tx)). 337 * 338 * The object need not be held in the transaction. 339 * 340 * If there are any holds on this object's buffers (via dmu_buf_hold()), 341 * or tx holds on the object (via dmu_tx_hold_object()), you can not 342 * free it; it fails and returns EBUSY. 343 * 344 * If the object is not allocated, it fails and returns ENOENT. 345 * 346 * Return 0 on success, or EBUSY or ENOENT as specified above. 347 */ 348 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 349 350 /* 351 * Find the next allocated or free object. 352 * 353 * The objectp parameter is in-out. It will be updated to be the next 354 * object which is allocated. Ignore objects which have not been 355 * modified since txg. 356 * 357 * XXX Can only be called on a objset with no dirty data. 358 * 359 * Returns 0 on success, or ENOENT if there are no more objects. 360 */ 361 int dmu_object_next(objset_t *os, uint64_t *objectp, 362 boolean_t hole, uint64_t txg); 363 364 /* 365 * Set the data blocksize for an object. 366 * 367 * The object cannot have any blocks allcated beyond the first. If 368 * the first block is allocated already, the new size must be greater 369 * than the current block size. If these conditions are not met, 370 * ENOTSUP will be returned. 371 * 372 * Returns 0 on success, or EBUSY if there are any holds on the object 373 * contents, or ENOTSUP as described above. 374 */ 375 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 376 int ibs, dmu_tx_t *tx); 377 378 /* 379 * Set the checksum property on a dnode. The new checksum algorithm will 380 * apply to all newly written blocks; existing blocks will not be affected. 381 */ 382 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 383 dmu_tx_t *tx); 384 385 /* 386 * Set the compress property on a dnode. The new compression algorithm will 387 * apply to all newly written blocks; existing blocks will not be affected. 388 */ 389 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 390 dmu_tx_t *tx); 391 392 /* 393 * Decide how to write a block: checksum, compression, number of copies, etc. 394 */ 395 #define WP_NOFILL 0x1 396 #define WP_DMU_SYNC 0x2 397 #define WP_SPILL 0x4 398 399 void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp, 400 struct zio_prop *zp); 401 /* 402 * The bonus data is accessed more or less like a regular buffer. 403 * You must dmu_bonus_hold() to get the buffer, which will give you a 404 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 405 * data. As with any normal buffer, you must call dmu_buf_read() to 406 * read db_data, dmu_buf_will_dirty() before modifying it, and the 407 * object must be held in an assigned transaction before calling 408 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 409 * buffer as well. You must release your hold with dmu_buf_rele(). 410 */ 411 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 412 int dmu_bonus_max(void); 413 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *); 414 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *); 415 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *); 416 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *); 417 418 /* 419 * Special spill buffer support used by "SA" framework 420 */ 421 422 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 423 int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags, 424 void *tag, dmu_buf_t **dbp); 425 int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 426 427 /* 428 * Obtain the DMU buffer from the specified object which contains the 429 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 430 * that it will remain in memory. You must release the hold with 431 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 432 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 433 * 434 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 435 * on the returned buffer before reading or writing the buffer's 436 * db_data. The comments for those routines describe what particular 437 * operations are valid after calling them. 438 * 439 * The object number must be a valid, allocated object number. 440 */ 441 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 442 void *tag, dmu_buf_t **, int flags); 443 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 444 void dmu_buf_rele(dmu_buf_t *db, void *tag); 445 uint64_t dmu_buf_refcount(dmu_buf_t *db); 446 447 /* 448 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 449 * range of an object. A pointer to an array of dmu_buf_t*'s is 450 * returned (in *dbpp). 451 * 452 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 453 * frees the array. The hold on the array of buffers MUST be released 454 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 455 * individually with dmu_buf_rele. 456 */ 457 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 458 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 459 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 460 461 /* 462 * Returns NULL on success, or the existing user ptr if it's already 463 * been set. 464 * 465 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 466 * 467 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 468 * will be set to db->db_data when you are allowed to access it. Note 469 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 470 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 471 * *user_data_ptr_ptr will be set to the new value when it changes. 472 * 473 * If non-NULL, pageout func will be called when this buffer is being 474 * excised from the cache, so that you can clean up the data structure 475 * pointed to by user_ptr. 476 * 477 * dmu_evict_user() will call the pageout func for all buffers in a 478 * objset with a given pageout func. 479 */ 480 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 481 dmu_buf_evict_func_t *pageout_func); 482 /* 483 * set_user_ie is the same as set_user, but request immediate eviction 484 * when hold count goes to zero. 485 */ 486 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 487 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 488 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 489 void *user_ptr, void *user_data_ptr_ptr, 490 dmu_buf_evict_func_t *pageout_func); 491 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 492 493 /* 494 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 495 */ 496 void *dmu_buf_get_user(dmu_buf_t *db); 497 498 /* 499 * Indicate that you are going to modify the buffer's data (db_data). 500 * 501 * The transaction (tx) must be assigned to a txg (ie. you've called 502 * dmu_tx_assign()). The buffer's object must be held in the tx 503 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 504 */ 505 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 506 507 /* 508 * Tells if the given dbuf is freeable. 509 */ 510 boolean_t dmu_buf_freeable(dmu_buf_t *); 511 512 /* 513 * You must create a transaction, then hold the objects which you will 514 * (or might) modify as part of this transaction. Then you must assign 515 * the transaction to a transaction group. Once the transaction has 516 * been assigned, you can modify buffers which belong to held objects as 517 * part of this transaction. You can't modify buffers before the 518 * transaction has been assigned; you can't modify buffers which don't 519 * belong to objects which this transaction holds; you can't hold 520 * objects once the transaction has been assigned. You may hold an 521 * object which you are going to free (with dmu_object_free()), but you 522 * don't have to. 523 * 524 * You can abort the transaction before it has been assigned. 525 * 526 * Note that you may hold buffers (with dmu_buf_hold) at any time, 527 * regardless of transaction state. 528 */ 529 530 #define DMU_NEW_OBJECT (-1ULL) 531 #define DMU_OBJECT_END (-1ULL) 532 533 dmu_tx_t *dmu_tx_create(objset_t *os); 534 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 535 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 536 uint64_t len); 537 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name); 538 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 539 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object); 540 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow); 541 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size); 542 void dmu_tx_abort(dmu_tx_t *tx); 543 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); 544 void dmu_tx_wait(dmu_tx_t *tx); 545 void dmu_tx_commit(dmu_tx_t *tx); 546 547 /* 548 * To register a commit callback, dmu_tx_callback_register() must be called. 549 * 550 * dcb_data is a pointer to caller private data that is passed on as a 551 * callback parameter. The caller is responsible for properly allocating and 552 * freeing it. 553 * 554 * When registering a callback, the transaction must be already created, but 555 * it cannot be committed or aborted. It can be assigned to a txg or not. 556 * 557 * The callback will be called after the transaction has been safely written 558 * to stable storage and will also be called if the dmu_tx is aborted. 559 * If there is any error which prevents the transaction from being committed to 560 * disk, the callback will be called with a value of error != 0. 561 */ 562 typedef void dmu_tx_callback_func_t(void *dcb_data, int error); 563 564 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func, 565 void *dcb_data); 566 567 /* 568 * Free up the data blocks for a defined range of a file. If size is 569 * -1, the range from offset to end-of-file is freed. 570 */ 571 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 572 uint64_t size, dmu_tx_t *tx); 573 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset, 574 uint64_t size); 575 int dmu_free_object(objset_t *os, uint64_t object); 576 577 /* 578 * Convenience functions. 579 * 580 * Canfail routines will return 0 on success, or an errno if there is a 581 * nonrecoverable I/O error. 582 */ 583 #define DMU_READ_PREFETCH 0 /* prefetch */ 584 #define DMU_READ_NO_PREFETCH 1 /* don't prefetch */ 585 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 586 void *buf, uint32_t flags); 587 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 588 const void *buf, dmu_tx_t *tx); 589 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 590 dmu_tx_t *tx); 591 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size); 592 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size, 593 dmu_tx_t *tx); 594 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size, 595 dmu_tx_t *tx); 596 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, 597 uint64_t size, struct page *pp, dmu_tx_t *tx); 598 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size); 599 void dmu_return_arcbuf(struct arc_buf *buf); 600 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf, 601 dmu_tx_t *tx); 602 int dmu_xuio_init(struct xuio *uio, int niov); 603 void dmu_xuio_fini(struct xuio *uio); 604 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off, 605 size_t n); 606 int dmu_xuio_cnt(struct xuio *uio); 607 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i); 608 void dmu_xuio_clear(struct xuio *uio, int i); 609 void xuio_stat_wbuf_copied(); 610 void xuio_stat_wbuf_nocopy(); 611 612 extern int zfs_prefetch_disable; 613 614 /* 615 * Asynchronously try to read in the data. 616 */ 617 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 618 uint64_t len); 619 620 typedef struct dmu_object_info { 621 /* All sizes are in bytes unless otherwise indicated. */ 622 uint32_t doi_data_block_size; 623 uint32_t doi_metadata_block_size; 624 dmu_object_type_t doi_type; 625 dmu_object_type_t doi_bonus_type; 626 uint64_t doi_bonus_size; 627 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 628 uint8_t doi_checksum; 629 uint8_t doi_compress; 630 uint8_t doi_pad[5]; 631 uint64_t doi_physical_blocks_512; /* data + metadata, 512b blks */ 632 uint64_t doi_max_offset; 633 uint64_t doi_fill_count; /* number of non-empty blocks */ 634 } dmu_object_info_t; 635 636 typedef void arc_byteswap_func_t(void *buf, size_t size); 637 638 typedef struct dmu_object_type_info { 639 dmu_object_byteswap_t ot_byteswap; 640 boolean_t ot_metadata; 641 char *ot_name; 642 } dmu_object_type_info_t; 643 644 typedef struct dmu_object_byteswap_info { 645 arc_byteswap_func_t *ob_func; 646 char *ob_name; 647 } dmu_object_byteswap_info_t; 648 649 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 650 extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS]; 651 652 /* 653 * Get information on a DMU object. 654 * 655 * Return 0 on success or ENOENT if object is not allocated. 656 * 657 * If doi is NULL, just indicates whether the object exists. 658 */ 659 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 660 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 661 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 662 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 663 u_longlong_t *nblk512); 664 665 typedef struct dmu_objset_stats { 666 uint64_t dds_num_clones; /* number of clones of this */ 667 uint64_t dds_creation_txg; 668 uint64_t dds_guid; 669 dmu_objset_type_t dds_type; 670 uint8_t dds_is_snapshot; 671 uint8_t dds_inconsistent; 672 char dds_origin[MAXNAMELEN]; 673 } dmu_objset_stats_t; 674 675 /* 676 * Get stats on a dataset. 677 */ 678 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat); 679 680 /* 681 * Add entries to the nvlist for all the objset's properties. See 682 * zfs_prop_table[] and zfs(1m) for details on the properties. 683 */ 684 void dmu_objset_stats(objset_t *os, struct nvlist *nv); 685 686 /* 687 * Get the space usage statistics for statvfs(). 688 * 689 * refdbytes is the amount of space "referenced" by this objset. 690 * availbytes is the amount of space available to this objset, taking 691 * into account quotas & reservations, assuming that no other objsets 692 * use the space first. These values correspond to the 'referenced' and 693 * 'available' properties, described in the zfs(1m) manpage. 694 * 695 * usedobjs and availobjs are the number of objects currently allocated, 696 * and available. 697 */ 698 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp, 699 uint64_t *usedobjsp, uint64_t *availobjsp); 700 701 /* 702 * The fsid_guid is a 56-bit ID that can change to avoid collisions. 703 * (Contrast with the ds_guid which is a 64-bit ID that will never 704 * change, so there is a small probability that it will collide.) 705 */ 706 uint64_t dmu_objset_fsid_guid(objset_t *os); 707 708 /* 709 * Get the [cm]time for an objset's snapshot dir 710 */ 711 timestruc_t dmu_objset_snap_cmtime(objset_t *os); 712 713 int dmu_objset_is_snapshot(objset_t *os); 714 715 extern struct spa *dmu_objset_spa(objset_t *os); 716 extern struct zilog *dmu_objset_zil(objset_t *os); 717 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 718 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 719 extern void dmu_objset_name(objset_t *os, char *buf); 720 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 721 extern uint64_t dmu_objset_id(objset_t *os); 722 extern uint64_t dmu_objset_syncprop(objset_t *os); 723 extern uint64_t dmu_objset_logbias(objset_t *os); 724 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 725 uint64_t *id, uint64_t *offp, boolean_t *case_conflict); 726 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real, 727 int maxlen, boolean_t *conflict); 728 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 729 uint64_t *idp, uint64_t *offp); 730 731 typedef int objset_used_cb_t(dmu_object_type_t bonustype, 732 void *bonus, uint64_t *userp, uint64_t *groupp); 733 extern void dmu_objset_register_type(dmu_objset_type_t ost, 734 objset_used_cb_t *cb); 735 extern void dmu_objset_set_user(objset_t *os, void *user_ptr); 736 extern void *dmu_objset_get_user(objset_t *os); 737 738 /* 739 * Return the txg number for the given assigned transaction. 740 */ 741 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 742 743 /* 744 * Synchronous write. 745 * If a parent zio is provided this function initiates a write on the 746 * provided buffer as a child of the parent zio. 747 * In the absence of a parent zio, the write is completed synchronously. 748 * At write completion, blk is filled with the bp of the written block. 749 * Note that while the data covered by this function will be on stable 750 * storage when the write completes this new data does not become a 751 * permanent part of the file until the associated transaction commits. 752 */ 753 754 /* 755 * {zfs,zvol,ztest}_get_done() args 756 */ 757 typedef struct zgd { 758 struct zilog *zgd_zilog; 759 struct blkptr *zgd_bp; 760 dmu_buf_t *zgd_db; 761 struct rl *zgd_rl; 762 void *zgd_private; 763 } zgd_t; 764 765 typedef void dmu_sync_cb_t(zgd_t *arg, int error); 766 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd); 767 768 /* 769 * Find the next hole or data block in file starting at *off 770 * Return found offset in *off. Return ESRCH for end of file. 771 */ 772 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 773 uint64_t *off); 774 775 /* 776 * Initial setup and final teardown. 777 */ 778 extern void dmu_init(void); 779 extern void dmu_fini(void); 780 781 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 782 uint64_t object, uint64_t offset, int len); 783 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 784 dmu_traverse_cb_t cb, void *arg); 785 786 int dmu_send(objset_t *tosnap, objset_t *fromsnap, 787 int outfd, struct vnode *vp, offset_t *off); 788 int dmu_send_estimate(objset_t *tosnap, objset_t *fromsnap, uint64_t *sizep); 789 790 typedef struct dmu_recv_cookie { 791 /* 792 * This structure is opaque! 793 * 794 * If logical and real are different, we are recving the stream 795 * into the "real" temporary clone, and then switching it with 796 * the "logical" target. 797 */ 798 struct dsl_dataset *drc_logical_ds; 799 struct dsl_dataset *drc_real_ds; 800 struct drr_begin *drc_drrb; 801 char *drc_tosnap; 802 char *drc_top_ds; 803 boolean_t drc_newfs; 804 boolean_t drc_force; 805 struct avl_tree *drc_guid_to_ds_map; 806 } dmu_recv_cookie_t; 807 808 int dmu_recv_begin(char *tofs, char *tosnap, char *topds, struct drr_begin *, 809 boolean_t force, objset_t *origin, dmu_recv_cookie_t *); 810 int dmu_recv_stream(dmu_recv_cookie_t *drc, struct vnode *vp, offset_t *voffp, 811 int cleanup_fd, uint64_t *action_handlep); 812 int dmu_recv_end(dmu_recv_cookie_t *drc); 813 814 int dmu_diff(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp, 815 offset_t *off); 816 817 /* CRC64 table */ 818 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 819 extern uint64_t zfs_crc64_table[256]; 820 821 #ifdef __cplusplus 822 } 823 #endif 824 825 #endif /* _SYS_DMU_H */ 826