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 48 #ifdef __cplusplus 49 extern "C" { 50 #endif 51 52 struct uio; 53 struct xuio; 54 struct page; 55 struct vnode; 56 struct spa; 57 struct zilog; 58 struct zio; 59 struct blkptr; 60 struct zap_cursor; 61 struct dsl_dataset; 62 struct dsl_pool; 63 struct dnode; 64 struct drr_begin; 65 struct drr_end; 66 struct zbookmark; 67 struct spa; 68 struct nvlist; 69 struct arc_buf; 70 struct zio_prop; 71 struct sa_handle; 72 73 typedef struct objset objset_t; 74 typedef struct dmu_tx dmu_tx_t; 75 typedef struct dsl_dir dsl_dir_t; 76 77 typedef enum dmu_object_byteswap { 78 DMU_BSWAP_UINT8, 79 DMU_BSWAP_UINT16, 80 DMU_BSWAP_UINT32, 81 DMU_BSWAP_UINT64, 82 DMU_BSWAP_ZAP, 83 DMU_BSWAP_DNODE, 84 DMU_BSWAP_OBJSET, 85 DMU_BSWAP_ZNODE, 86 DMU_BSWAP_OLDACL, 87 DMU_BSWAP_ACL, 88 /* 89 * Allocating a new byteswap type number makes the on-disk format 90 * incompatible with any other format that uses the same number. 91 * 92 * Data can usually be structured to work with one of the 93 * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types. 94 */ 95 DMU_BSWAP_NUMFUNCS 96 } dmu_object_byteswap_t; 97 98 #define DMU_OT_NEWTYPE 0x80 99 #define DMU_OT_METADATA 0x40 100 #define DMU_OT_BYTESWAP_MASK 0x3f 101 102 /* 103 * Defines a uint8_t object type. Object types specify if the data 104 * in the object is metadata (boolean) and how to byteswap the data 105 * (dmu_object_byteswap_t). 106 */ 107 #define DMU_OT(byteswap, metadata) \ 108 (DMU_OT_NEWTYPE | \ 109 ((metadata) ? DMU_OT_METADATA : 0) | \ 110 ((byteswap) & DMU_OT_BYTESWAP_MASK)) 111 112 #define DMU_OT_IS_VALID(ot) (((ot) & DMU_OT_NEWTYPE) ? \ 113 ((ot) & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS : \ 114 (ot) < DMU_OT_NUMTYPES) 115 116 #define DMU_OT_IS_METADATA(ot) (((ot) & DMU_OT_NEWTYPE) ? \ 117 ((ot) & DMU_OT_METADATA) : \ 118 dmu_ot[(ot)].ot_metadata) 119 120 #define DMU_OT_BYTESWAP(ot) (((ot) & DMU_OT_NEWTYPE) ? \ 121 ((ot) & DMU_OT_BYTESWAP_MASK) : \ 122 dmu_ot[(ot)].ot_byteswap) 123 124 typedef enum dmu_object_type { 125 DMU_OT_NONE, 126 /* general: */ 127 DMU_OT_OBJECT_DIRECTORY, /* ZAP */ 128 DMU_OT_OBJECT_ARRAY, /* UINT64 */ 129 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */ 130 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */ 131 DMU_OT_BPOBJ, /* UINT64 */ 132 DMU_OT_BPOBJ_HDR, /* UINT64 */ 133 /* spa: */ 134 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */ 135 DMU_OT_SPACE_MAP, /* UINT64 */ 136 /* zil: */ 137 DMU_OT_INTENT_LOG, /* UINT64 */ 138 /* dmu: */ 139 DMU_OT_DNODE, /* DNODE */ 140 DMU_OT_OBJSET, /* OBJSET */ 141 /* dsl: */ 142 DMU_OT_DSL_DIR, /* UINT64 */ 143 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */ 144 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */ 145 DMU_OT_DSL_PROPS, /* ZAP */ 146 DMU_OT_DSL_DATASET, /* UINT64 */ 147 /* zpl: */ 148 DMU_OT_ZNODE, /* ZNODE */ 149 DMU_OT_OLDACL, /* Old ACL */ 150 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */ 151 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */ 152 DMU_OT_MASTER_NODE, /* ZAP */ 153 DMU_OT_UNLINKED_SET, /* ZAP */ 154 /* zvol: */ 155 DMU_OT_ZVOL, /* UINT8 */ 156 DMU_OT_ZVOL_PROP, /* ZAP */ 157 /* other; for testing only! */ 158 DMU_OT_PLAIN_OTHER, /* UINT8 */ 159 DMU_OT_UINT64_OTHER, /* UINT64 */ 160 DMU_OT_ZAP_OTHER, /* ZAP */ 161 /* new object types: */ 162 DMU_OT_ERROR_LOG, /* ZAP */ 163 DMU_OT_SPA_HISTORY, /* UINT8 */ 164 DMU_OT_SPA_HISTORY_OFFSETS, /* spa_his_phys_t */ 165 DMU_OT_POOL_PROPS, /* ZAP */ 166 DMU_OT_DSL_PERMS, /* ZAP */ 167 DMU_OT_ACL, /* ACL */ 168 DMU_OT_SYSACL, /* SYSACL */ 169 DMU_OT_FUID, /* FUID table (Packed NVLIST UINT8) */ 170 DMU_OT_FUID_SIZE, /* FUID table size UINT64 */ 171 DMU_OT_NEXT_CLONES, /* ZAP */ 172 DMU_OT_SCAN_QUEUE, /* ZAP */ 173 DMU_OT_USERGROUP_USED, /* ZAP */ 174 DMU_OT_USERGROUP_QUOTA, /* ZAP */ 175 DMU_OT_USERREFS, /* ZAP */ 176 DMU_OT_DDT_ZAP, /* ZAP */ 177 DMU_OT_DDT_STATS, /* ZAP */ 178 DMU_OT_SA, /* System attr */ 179 DMU_OT_SA_MASTER_NODE, /* ZAP */ 180 DMU_OT_SA_ATTR_REGISTRATION, /* ZAP */ 181 DMU_OT_SA_ATTR_LAYOUTS, /* ZAP */ 182 DMU_OT_SCAN_XLATE, /* ZAP */ 183 DMU_OT_DEDUP, /* fake dedup BP from ddt_bp_create() */ 184 DMU_OT_DEADLIST, /* ZAP */ 185 DMU_OT_DEADLIST_HDR, /* UINT64 */ 186 DMU_OT_DSL_CLONES, /* ZAP */ 187 DMU_OT_BPOBJ_SUBOBJ, /* UINT64 */ 188 /* 189 * Do not allocate new object types here. Doing so makes the on-disk 190 * format incompatible with any other format that uses the same object 191 * type number. 192 * 193 * When creating an object which does not have one of the above types 194 * use the DMU_OTN_* type with the correct byteswap and metadata 195 * values. 196 * 197 * The DMU_OTN_* types do not have entries in the dmu_ot table, 198 * use the DMU_OT_IS_METDATA() and DMU_OT_BYTESWAP() macros instead 199 * of indexing into dmu_ot directly (this works for both DMU_OT_* types 200 * and DMU_OTN_* types). 201 */ 202 DMU_OT_NUMTYPES, 203 204 /* 205 * Names for valid types declared with DMU_OT(). 206 */ 207 DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE), 208 DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE), 209 DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE), 210 DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE), 211 DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE), 212 DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE), 213 DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE), 214 DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE), 215 DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE), 216 DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE), 217 } dmu_object_type_t; 218 219 typedef enum dmu_objset_type { 220 DMU_OST_NONE, 221 DMU_OST_META, 222 DMU_OST_ZFS, 223 DMU_OST_ZVOL, 224 DMU_OST_OTHER, /* For testing only! */ 225 DMU_OST_ANY, /* Be careful! */ 226 DMU_OST_NUMTYPES 227 } dmu_objset_type_t; 228 229 void byteswap_uint64_array(void *buf, size_t size); 230 void byteswap_uint32_array(void *buf, size_t size); 231 void byteswap_uint16_array(void *buf, size_t size); 232 void byteswap_uint8_array(void *buf, size_t size); 233 void zap_byteswap(void *buf, size_t size); 234 void zfs_oldacl_byteswap(void *buf, size_t size); 235 void zfs_acl_byteswap(void *buf, size_t size); 236 void zfs_znode_byteswap(void *buf, size_t size); 237 238 #define DS_FIND_SNAPSHOTS (1<<0) 239 #define DS_FIND_CHILDREN (1<<1) 240 241 /* 242 * The maximum number of bytes that can be accessed as part of one 243 * operation, including metadata. 244 */ 245 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 246 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */ 247 248 #define DMU_USERUSED_OBJECT (-1ULL) 249 #define DMU_GROUPUSED_OBJECT (-2ULL) 250 #define DMU_DEADLIST_OBJECT (-3ULL) 251 252 /* 253 * artificial blkids for bonus buffer and spill blocks 254 */ 255 #define DMU_BONUS_BLKID (-1ULL) 256 #define DMU_SPILL_BLKID (-2ULL) 257 /* 258 * Public routines to create, destroy, open, and close objsets. 259 */ 260 int dmu_objset_hold(const char *name, void *tag, objset_t **osp); 261 int dmu_objset_own(const char *name, dmu_objset_type_t type, 262 boolean_t readonly, void *tag, objset_t **osp); 263 void dmu_objset_rele(objset_t *os, void *tag); 264 void dmu_objset_disown(objset_t *os, void *tag); 265 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp); 266 267 int dmu_objset_evict_dbufs(objset_t *os); 268 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags, 269 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg); 270 int dmu_objset_clone(const char *name, struct dsl_dataset *clone_origin, 271 uint64_t flags); 272 int dmu_objset_destroy(const char *name, boolean_t defer); 273 int dmu_snapshots_destroy_nvl(struct nvlist *snaps, boolean_t defer, char *); 274 int dmu_objset_snapshot(char *fsname, char *snapname, char *tag, 275 struct nvlist *props, boolean_t recursive, boolean_t temporary, int fd); 276 int dmu_objset_rename(const char *name, const char *newname, 277 boolean_t recursive); 278 int dmu_objset_find(char *name, int func(const char *, void *), void *arg, 279 int flags); 280 void dmu_objset_byteswap(void *buf, size_t size); 281 282 typedef struct dmu_buf { 283 uint64_t db_object; /* object that this buffer is part of */ 284 uint64_t db_offset; /* byte offset in this object */ 285 uint64_t db_size; /* size of buffer in bytes */ 286 void *db_data; /* data in buffer */ 287 } dmu_buf_t; 288 289 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 290 291 /* 292 * The names of zap entries in the DIRECTORY_OBJECT of the MOS. 293 */ 294 #define DMU_POOL_DIRECTORY_OBJECT 1 295 #define DMU_POOL_CONFIG "config" 296 #define DMU_POOL_FEATURES_FOR_WRITE "features_for_write" 297 #define DMU_POOL_FEATURES_FOR_READ "features_for_read" 298 #define DMU_POOL_FEATURE_DESCRIPTIONS "feature_descriptions" 299 #define DMU_POOL_ROOT_DATASET "root_dataset" 300 #define DMU_POOL_SYNC_BPOBJ "sync_bplist" 301 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 302 #define DMU_POOL_ERRLOG_LAST "errlog_last" 303 #define DMU_POOL_SPARES "spares" 304 #define DMU_POOL_DEFLATE "deflate" 305 #define DMU_POOL_HISTORY "history" 306 #define DMU_POOL_PROPS "pool_props" 307 #define DMU_POOL_L2CACHE "l2cache" 308 #define DMU_POOL_TMP_USERREFS "tmp_userrefs" 309 #define DMU_POOL_DDT "DDT-%s-%s-%s" 310 #define DMU_POOL_DDT_STATS "DDT-statistics" 311 #define DMU_POOL_CREATION_VERSION "creation_version" 312 #define DMU_POOL_SCAN "scan" 313 #define DMU_POOL_FREE_BPOBJ "free_bpobj" 314 #define DMU_POOL_BPTREE_OBJ "bptree_obj" 315 316 /* 317 * Allocate an object from this objset. The range of object numbers 318 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 319 * 320 * The transaction must be assigned to a txg. The newly allocated 321 * object will be "held" in the transaction (ie. you can modify the 322 * newly allocated object in this transaction). 323 * 324 * dmu_object_alloc() chooses an object and returns it in *objectp. 325 * 326 * dmu_object_claim() allocates a specific object number. If that 327 * number is already allocated, it fails and returns EEXIST. 328 * 329 * Return 0 on success, or ENOSPC or EEXIST as specified above. 330 */ 331 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot, 332 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 333 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot, 334 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 335 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 336 int blocksize, dmu_object_type_t bonustype, int bonuslen); 337 338 /* 339 * Free an object from this objset. 340 * 341 * The object's data will be freed as well (ie. you don't need to call 342 * dmu_free(object, 0, -1, tx)). 343 * 344 * The object need not be held in the transaction. 345 * 346 * If there are any holds on this object's buffers (via dmu_buf_hold()), 347 * or tx holds on the object (via dmu_tx_hold_object()), you can not 348 * free it; it fails and returns EBUSY. 349 * 350 * If the object is not allocated, it fails and returns ENOENT. 351 * 352 * Return 0 on success, or EBUSY or ENOENT as specified above. 353 */ 354 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 355 356 /* 357 * Find the next allocated or free object. 358 * 359 * The objectp parameter is in-out. It will be updated to be the next 360 * object which is allocated. Ignore objects which have not been 361 * modified since txg. 362 * 363 * XXX Can only be called on a objset with no dirty data. 364 * 365 * Returns 0 on success, or ENOENT if there are no more objects. 366 */ 367 int dmu_object_next(objset_t *os, uint64_t *objectp, 368 boolean_t hole, uint64_t txg); 369 370 /* 371 * Set the data blocksize for an object. 372 * 373 * The object cannot have any blocks allcated beyond the first. If 374 * the first block is allocated already, the new size must be greater 375 * than the current block size. If these conditions are not met, 376 * ENOTSUP will be returned. 377 * 378 * Returns 0 on success, or EBUSY if there are any holds on the object 379 * contents, or ENOTSUP as described above. 380 */ 381 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 382 int ibs, dmu_tx_t *tx); 383 384 /* 385 * Set the checksum property on a dnode. The new checksum algorithm will 386 * apply to all newly written blocks; existing blocks will not be affected. 387 */ 388 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 389 dmu_tx_t *tx); 390 391 /* 392 * Set the compress property on a dnode. The new compression algorithm will 393 * apply to all newly written blocks; existing blocks will not be affected. 394 */ 395 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 396 dmu_tx_t *tx); 397 398 /* 399 * Decide how to write a block: checksum, compression, number of copies, etc. 400 */ 401 #define WP_NOFILL 0x1 402 #define WP_DMU_SYNC 0x2 403 #define WP_SPILL 0x4 404 405 void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp, 406 struct zio_prop *zp); 407 /* 408 * The bonus data is accessed more or less like a regular buffer. 409 * You must dmu_bonus_hold() to get the buffer, which will give you a 410 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 411 * data. As with any normal buffer, you must call dmu_buf_read() to 412 * read db_data, dmu_buf_will_dirty() before modifying it, and the 413 * object must be held in an assigned transaction before calling 414 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 415 * buffer as well. You must release your hold with dmu_buf_rele(). 416 */ 417 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 418 int dmu_bonus_max(void); 419 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *); 420 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *); 421 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *); 422 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *); 423 424 /* 425 * Special spill buffer support used by "SA" framework 426 */ 427 428 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 429 int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags, 430 void *tag, dmu_buf_t **dbp); 431 int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp); 432 433 /* 434 * Obtain the DMU buffer from the specified object which contains the 435 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 436 * that it will remain in memory. You must release the hold with 437 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 438 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 439 * 440 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 441 * on the returned buffer before reading or writing the buffer's 442 * db_data. The comments for those routines describe what particular 443 * operations are valid after calling them. 444 * 445 * The object number must be a valid, allocated object number. 446 */ 447 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 448 void *tag, dmu_buf_t **, int flags); 449 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 450 void dmu_buf_rele(dmu_buf_t *db, void *tag); 451 uint64_t dmu_buf_refcount(dmu_buf_t *db); 452 453 /* 454 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 455 * range of an object. A pointer to an array of dmu_buf_t*'s is 456 * returned (in *dbpp). 457 * 458 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 459 * frees the array. The hold on the array of buffers MUST be released 460 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 461 * individually with dmu_buf_rele. 462 */ 463 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 464 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 465 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 466 467 /* 468 * Returns NULL on success, or the existing user ptr if it's already 469 * been set. 470 * 471 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 472 * 473 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 474 * will be set to db->db_data when you are allowed to access it. Note 475 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 476 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 477 * *user_data_ptr_ptr will be set to the new value when it changes. 478 * 479 * If non-NULL, pageout func will be called when this buffer is being 480 * excised from the cache, so that you can clean up the data structure 481 * pointed to by user_ptr. 482 * 483 * dmu_evict_user() will call the pageout func for all buffers in a 484 * objset with a given pageout func. 485 */ 486 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 487 dmu_buf_evict_func_t *pageout_func); 488 /* 489 * set_user_ie is the same as set_user, but request immediate eviction 490 * when hold count goes to zero. 491 */ 492 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 493 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 494 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 495 void *user_ptr, void *user_data_ptr_ptr, 496 dmu_buf_evict_func_t *pageout_func); 497 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 498 499 /* 500 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 501 */ 502 void *dmu_buf_get_user(dmu_buf_t *db); 503 504 /* 505 * Indicate that you are going to modify the buffer's data (db_data). 506 * 507 * The transaction (tx) must be assigned to a txg (ie. you've called 508 * dmu_tx_assign()). The buffer's object must be held in the tx 509 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 510 */ 511 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 512 513 /* 514 * Tells if the given dbuf is freeable. 515 */ 516 boolean_t dmu_buf_freeable(dmu_buf_t *); 517 518 /* 519 * You must create a transaction, then hold the objects which you will 520 * (or might) modify as part of this transaction. Then you must assign 521 * the transaction to a transaction group. Once the transaction has 522 * been assigned, you can modify buffers which belong to held objects as 523 * part of this transaction. You can't modify buffers before the 524 * transaction has been assigned; you can't modify buffers which don't 525 * belong to objects which this transaction holds; you can't hold 526 * objects once the transaction has been assigned. You may hold an 527 * object which you are going to free (with dmu_object_free()), but you 528 * don't have to. 529 * 530 * You can abort the transaction before it has been assigned. 531 * 532 * Note that you may hold buffers (with dmu_buf_hold) at any time, 533 * regardless of transaction state. 534 */ 535 536 #define DMU_NEW_OBJECT (-1ULL) 537 #define DMU_OBJECT_END (-1ULL) 538 539 dmu_tx_t *dmu_tx_create(objset_t *os); 540 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 541 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 542 uint64_t len); 543 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name); 544 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 545 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object); 546 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow); 547 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size); 548 void dmu_tx_abort(dmu_tx_t *tx); 549 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); 550 void dmu_tx_wait(dmu_tx_t *tx); 551 void dmu_tx_commit(dmu_tx_t *tx); 552 553 /* 554 * To register a commit callback, dmu_tx_callback_register() must be called. 555 * 556 * dcb_data is a pointer to caller private data that is passed on as a 557 * callback parameter. The caller is responsible for properly allocating and 558 * freeing it. 559 * 560 * When registering a callback, the transaction must be already created, but 561 * it cannot be committed or aborted. It can be assigned to a txg or not. 562 * 563 * The callback will be called after the transaction has been safely written 564 * to stable storage and will also be called if the dmu_tx is aborted. 565 * If there is any error which prevents the transaction from being committed to 566 * disk, the callback will be called with a value of error != 0. 567 */ 568 typedef void dmu_tx_callback_func_t(void *dcb_data, int error); 569 570 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func, 571 void *dcb_data); 572 573 /* 574 * Free up the data blocks for a defined range of a file. If size is 575 * -1, the range from offset to end-of-file is freed. 576 */ 577 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 578 uint64_t size, dmu_tx_t *tx); 579 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset, 580 uint64_t size); 581 int dmu_free_object(objset_t *os, uint64_t object); 582 583 /* 584 * Convenience functions. 585 * 586 * Canfail routines will return 0 on success, or an errno if there is a 587 * nonrecoverable I/O error. 588 */ 589 #define DMU_READ_PREFETCH 0 /* prefetch */ 590 #define DMU_READ_NO_PREFETCH 1 /* don't prefetch */ 591 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 592 void *buf, uint32_t flags); 593 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 594 const void *buf, dmu_tx_t *tx); 595 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 596 dmu_tx_t *tx); 597 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size); 598 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size, 599 dmu_tx_t *tx); 600 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size, 601 dmu_tx_t *tx); 602 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, 603 uint64_t size, struct page *pp, dmu_tx_t *tx); 604 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size); 605 void dmu_return_arcbuf(struct arc_buf *buf); 606 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf, 607 dmu_tx_t *tx); 608 int dmu_xuio_init(struct xuio *uio, int niov); 609 void dmu_xuio_fini(struct xuio *uio); 610 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off, 611 size_t n); 612 int dmu_xuio_cnt(struct xuio *uio); 613 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i); 614 void dmu_xuio_clear(struct xuio *uio, int i); 615 void xuio_stat_wbuf_copied(); 616 void xuio_stat_wbuf_nocopy(); 617 618 extern int zfs_prefetch_disable; 619 620 /* 621 * Asynchronously try to read in the data. 622 */ 623 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 624 uint64_t len); 625 626 typedef struct dmu_object_info { 627 /* All sizes are in bytes unless otherwise indicated. */ 628 uint32_t doi_data_block_size; 629 uint32_t doi_metadata_block_size; 630 dmu_object_type_t doi_type; 631 dmu_object_type_t doi_bonus_type; 632 uint64_t doi_bonus_size; 633 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 634 uint8_t doi_checksum; 635 uint8_t doi_compress; 636 uint8_t doi_pad[5]; 637 uint64_t doi_physical_blocks_512; /* data + metadata, 512b blks */ 638 uint64_t doi_max_offset; 639 uint64_t doi_fill_count; /* number of non-empty blocks */ 640 } dmu_object_info_t; 641 642 typedef void arc_byteswap_func_t(void *buf, size_t size); 643 644 typedef struct dmu_object_type_info { 645 dmu_object_byteswap_t ot_byteswap; 646 boolean_t ot_metadata; 647 char *ot_name; 648 } dmu_object_type_info_t; 649 650 typedef struct dmu_object_byteswap_info { 651 arc_byteswap_func_t *ob_func; 652 char *ob_name; 653 } dmu_object_byteswap_info_t; 654 655 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 656 extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS]; 657 658 /* 659 * Get information on a DMU object. 660 * 661 * Return 0 on success or ENOENT if object is not allocated. 662 * 663 * If doi is NULL, just indicates whether the object exists. 664 */ 665 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 666 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 667 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 668 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 669 u_longlong_t *nblk512); 670 671 typedef struct dmu_objset_stats { 672 uint64_t dds_num_clones; /* number of clones of this */ 673 uint64_t dds_creation_txg; 674 uint64_t dds_guid; 675 dmu_objset_type_t dds_type; 676 uint8_t dds_is_snapshot; 677 uint8_t dds_inconsistent; 678 char dds_origin[MAXNAMELEN]; 679 } dmu_objset_stats_t; 680 681 /* 682 * Get stats on a dataset. 683 */ 684 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat); 685 686 /* 687 * Add entries to the nvlist for all the objset's properties. See 688 * zfs_prop_table[] and zfs(1m) for details on the properties. 689 */ 690 void dmu_objset_stats(objset_t *os, struct nvlist *nv); 691 692 /* 693 * Get the space usage statistics for statvfs(). 694 * 695 * refdbytes is the amount of space "referenced" by this objset. 696 * availbytes is the amount of space available to this objset, taking 697 * into account quotas & reservations, assuming that no other objsets 698 * use the space first. These values correspond to the 'referenced' and 699 * 'available' properties, described in the zfs(1m) manpage. 700 * 701 * usedobjs and availobjs are the number of objects currently allocated, 702 * and available. 703 */ 704 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp, 705 uint64_t *usedobjsp, uint64_t *availobjsp); 706 707 /* 708 * The fsid_guid is a 56-bit ID that can change to avoid collisions. 709 * (Contrast with the ds_guid which is a 64-bit ID that will never 710 * change, so there is a small probability that it will collide.) 711 */ 712 uint64_t dmu_objset_fsid_guid(objset_t *os); 713 714 /* 715 * Get the [cm]time for an objset's snapshot dir 716 */ 717 timestruc_t dmu_objset_snap_cmtime(objset_t *os); 718 719 int dmu_objset_is_snapshot(objset_t *os); 720 721 extern struct spa *dmu_objset_spa(objset_t *os); 722 extern struct zilog *dmu_objset_zil(objset_t *os); 723 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 724 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 725 extern void dmu_objset_name(objset_t *os, char *buf); 726 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 727 extern uint64_t dmu_objset_id(objset_t *os); 728 extern uint64_t dmu_objset_syncprop(objset_t *os); 729 extern uint64_t dmu_objset_logbias(objset_t *os); 730 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 731 uint64_t *id, uint64_t *offp, boolean_t *case_conflict); 732 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real, 733 int maxlen, boolean_t *conflict); 734 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 735 uint64_t *idp, uint64_t *offp); 736 737 typedef int objset_used_cb_t(dmu_object_type_t bonustype, 738 void *bonus, uint64_t *userp, uint64_t *groupp); 739 extern void dmu_objset_register_type(dmu_objset_type_t ost, 740 objset_used_cb_t *cb); 741 extern void dmu_objset_set_user(objset_t *os, void *user_ptr); 742 extern void *dmu_objset_get_user(objset_t *os); 743 744 /* 745 * Return the txg number for the given assigned transaction. 746 */ 747 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 748 749 /* 750 * Synchronous write. 751 * If a parent zio is provided this function initiates a write on the 752 * provided buffer as a child of the parent zio. 753 * In the absence of a parent zio, the write is completed synchronously. 754 * At write completion, blk is filled with the bp of the written block. 755 * Note that while the data covered by this function will be on stable 756 * storage when the write completes this new data does not become a 757 * permanent part of the file until the associated transaction commits. 758 */ 759 760 /* 761 * {zfs,zvol,ztest}_get_done() args 762 */ 763 typedef struct zgd { 764 struct zilog *zgd_zilog; 765 struct blkptr *zgd_bp; 766 dmu_buf_t *zgd_db; 767 struct rl *zgd_rl; 768 void *zgd_private; 769 } zgd_t; 770 771 typedef void dmu_sync_cb_t(zgd_t *arg, int error); 772 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd); 773 774 /* 775 * Find the next hole or data block in file starting at *off 776 * Return found offset in *off. Return ESRCH for end of file. 777 */ 778 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 779 uint64_t *off); 780 781 /* 782 * Initial setup and final teardown. 783 */ 784 extern void dmu_init(void); 785 extern void dmu_fini(void); 786 787 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 788 uint64_t object, uint64_t offset, int len); 789 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 790 dmu_traverse_cb_t cb, void *arg); 791 792 int dmu_send(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin, 793 int outfd, struct vnode *vp, offset_t *off); 794 int dmu_send_estimate(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorign, 795 uint64_t *sizep); 796 797 typedef struct dmu_recv_cookie { 798 /* 799 * This structure is opaque! 800 * 801 * If logical and real are different, we are recving the stream 802 * into the "real" temporary clone, and then switching it with 803 * the "logical" target. 804 */ 805 struct dsl_dataset *drc_logical_ds; 806 struct dsl_dataset *drc_real_ds; 807 struct drr_begin *drc_drrb; 808 char *drc_tosnap; 809 char *drc_top_ds; 810 boolean_t drc_newfs; 811 boolean_t drc_force; 812 struct avl_tree *drc_guid_to_ds_map; 813 } dmu_recv_cookie_t; 814 815 int dmu_recv_begin(char *tofs, char *tosnap, char *topds, struct drr_begin *, 816 boolean_t force, objset_t *origin, dmu_recv_cookie_t *); 817 int dmu_recv_stream(dmu_recv_cookie_t *drc, struct vnode *vp, offset_t *voffp, 818 int cleanup_fd, uint64_t *action_handlep); 819 int dmu_recv_end(dmu_recv_cookie_t *drc); 820 821 int dmu_diff(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp, 822 offset_t *off); 823 824 /* CRC64 table */ 825 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 826 extern uint64_t zfs_crc64_table[256]; 827 828 #ifdef __cplusplus 829 } 830 #endif 831 832 #endif /* _SYS_DMU_H */ 833