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 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_DMU_H 27 #define _SYS_DMU_H 28 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 /* 32 * This file describes the interface that the DMU provides for its 33 * consumers. 34 * 35 * The DMU also interacts with the SPA. That interface is described in 36 * dmu_spa.h. 37 */ 38 39 #include <sys/inttypes.h> 40 #include <sys/types.h> 41 #include <sys/param.h> 42 #include <sys/cred.h> 43 44 #ifdef __cplusplus 45 extern "C" { 46 #endif 47 48 struct uio; 49 struct page; 50 struct vnode; 51 struct spa; 52 struct zilog; 53 struct zio; 54 struct blkptr; 55 struct zap_cursor; 56 struct dsl_dataset; 57 struct dsl_pool; 58 struct dnode; 59 struct drr_begin; 60 struct drr_end; 61 struct zbookmark; 62 struct spa; 63 struct nvlist; 64 struct objset_impl; 65 66 typedef struct objset objset_t; 67 typedef struct dmu_tx dmu_tx_t; 68 typedef struct dsl_dir dsl_dir_t; 69 70 typedef enum dmu_object_type { 71 DMU_OT_NONE, 72 /* general: */ 73 DMU_OT_OBJECT_DIRECTORY, /* ZAP */ 74 DMU_OT_OBJECT_ARRAY, /* UINT64 */ 75 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */ 76 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */ 77 DMU_OT_BPLIST, /* UINT64 */ 78 DMU_OT_BPLIST_HDR, /* UINT64 */ 79 /* spa: */ 80 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */ 81 DMU_OT_SPACE_MAP, /* UINT64 */ 82 /* zil: */ 83 DMU_OT_INTENT_LOG, /* UINT64 */ 84 /* dmu: */ 85 DMU_OT_DNODE, /* DNODE */ 86 DMU_OT_OBJSET, /* OBJSET */ 87 /* dsl: */ 88 DMU_OT_DSL_DIR, /* UINT64 */ 89 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */ 90 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */ 91 DMU_OT_DSL_PROPS, /* ZAP */ 92 DMU_OT_DSL_DATASET, /* UINT64 */ 93 /* zpl: */ 94 DMU_OT_ZNODE, /* ZNODE */ 95 DMU_OT_ACL, /* ACL */ 96 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */ 97 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */ 98 DMU_OT_MASTER_NODE, /* ZAP */ 99 DMU_OT_UNLINKED_SET, /* ZAP */ 100 /* zvol: */ 101 DMU_OT_ZVOL, /* UINT8 */ 102 DMU_OT_ZVOL_PROP, /* ZAP */ 103 /* other; for testing only! */ 104 DMU_OT_PLAIN_OTHER, /* UINT8 */ 105 DMU_OT_UINT64_OTHER, /* UINT64 */ 106 DMU_OT_ZAP_OTHER, /* ZAP */ 107 /* new object types: */ 108 DMU_OT_ERROR_LOG, /* ZAP */ 109 DMU_OT_SPA_HISTORY, /* UINT8 */ 110 DMU_OT_SPA_HISTORY_OFFSETS, /* spa_his_phys_t */ 111 DMU_OT_POOL_PROPS, /* ZAP */ 112 DMU_OT_DSL_PERMS, /* ZAP */ 113 DMU_OT_NUMTYPES 114 } dmu_object_type_t; 115 116 typedef enum dmu_objset_type { 117 DMU_OST_NONE, 118 DMU_OST_META, 119 DMU_OST_ZFS, 120 DMU_OST_ZVOL, 121 DMU_OST_OTHER, /* For testing only! */ 122 DMU_OST_ANY, /* Be careful! */ 123 DMU_OST_NUMTYPES 124 } dmu_objset_type_t; 125 126 void byteswap_uint64_array(void *buf, size_t size); 127 void byteswap_uint32_array(void *buf, size_t size); 128 void byteswap_uint16_array(void *buf, size_t size); 129 void byteswap_uint8_array(void *buf, size_t size); 130 void zap_byteswap(void *buf, size_t size); 131 void zfs_acl_byteswap(void *buf, size_t size); 132 void zfs_znode_byteswap(void *buf, size_t size); 133 134 #define DS_MODE_NONE 0 /* invalid, to aid debugging */ 135 #define DS_MODE_STANDARD 1 /* normal access, no special needs */ 136 #define DS_MODE_PRIMARY 2 /* the "main" access, e.g. a mount */ 137 #define DS_MODE_EXCLUSIVE 3 /* exclusive access, e.g. to destroy */ 138 #define DS_MODE_LEVELS 4 139 #define DS_MODE_LEVEL(x) ((x) & (DS_MODE_LEVELS - 1)) 140 #define DS_MODE_READONLY 0x8 141 #define DS_MODE_IS_READONLY(x) ((x) & DS_MODE_READONLY) 142 #define DS_MODE_INCONSISTENT 0x10 143 #define DS_MODE_IS_INCONSISTENT(x) ((x) & DS_MODE_INCONSISTENT) 144 145 #define DS_FIND_SNAPSHOTS (1<<0) 146 #define DS_FIND_CHILDREN (1<<1) 147 148 /* 149 * The maximum number of bytes that can be accessed as part of one 150 * operation, including metadata. 151 */ 152 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 153 154 /* 155 * Public routines to create, destroy, open, and close objsets. 156 */ 157 int dmu_objset_open(const char *name, dmu_objset_type_t type, int mode, 158 objset_t **osp); 159 void dmu_objset_close(objset_t *os); 160 int dmu_objset_evict_dbufs(objset_t *os, boolean_t try); 161 int dmu_objset_create(const char *name, dmu_objset_type_t type, 162 objset_t *clone_parent, 163 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg); 164 int dmu_objset_destroy(const char *name); 165 int dmu_snapshots_destroy(char *fsname, char *snapname); 166 int dmu_objset_rollback(const char *name); 167 int dmu_objset_snapshot(char *fsname, char *snapname, boolean_t recursive); 168 int dmu_objset_rename(const char *name, const char *newname, 169 boolean_t recursive); 170 int dmu_objset_find(char *name, int func(char *, void *), void *arg, 171 int flags); 172 void dmu_objset_byteswap(void *buf, size_t size); 173 174 typedef struct dmu_buf { 175 uint64_t db_object; /* object that this buffer is part of */ 176 uint64_t db_offset; /* byte offset in this object */ 177 uint64_t db_size; /* size of buffer in bytes */ 178 void *db_data; /* data in buffer */ 179 } dmu_buf_t; 180 181 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 182 183 /* 184 * Callback function to perform byte swapping on a block. 185 */ 186 typedef void dmu_byteswap_func_t(void *buf, size_t size); 187 188 /* 189 * The names of zap entries in the DIRECTORY_OBJECT of the MOS. 190 */ 191 #define DMU_POOL_DIRECTORY_OBJECT 1 192 #define DMU_POOL_CONFIG "config" 193 #define DMU_POOL_ROOT_DATASET "root_dataset" 194 #define DMU_POOL_SYNC_BPLIST "sync_bplist" 195 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 196 #define DMU_POOL_ERRLOG_LAST "errlog_last" 197 #define DMU_POOL_SPARES "spares" 198 #define DMU_POOL_DEFLATE "deflate" 199 #define DMU_POOL_HISTORY "history" 200 #define DMU_POOL_PROPS "pool_props" 201 202 /* 203 * Allocate an object from this objset. The range of object numbers 204 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 205 * 206 * The transaction must be assigned to a txg. The newly allocated 207 * object will be "held" in the transaction (ie. you can modify the 208 * newly allocated object in this transaction). 209 * 210 * dmu_object_alloc() chooses an object and returns it in *objectp. 211 * 212 * dmu_object_claim() allocates a specific object number. If that 213 * number is already allocated, it fails and returns EEXIST. 214 * 215 * Return 0 on success, or ENOSPC or EEXIST as specified above. 216 */ 217 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot, 218 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 219 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot, 220 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 221 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 222 int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 223 224 /* 225 * Free an object from this objset. 226 * 227 * The object's data will be freed as well (ie. you don't need to call 228 * dmu_free(object, 0, -1, tx)). 229 * 230 * The object need not be held in the transaction. 231 * 232 * If there are any holds on this object's buffers (via dmu_buf_hold()), 233 * or tx holds on the object (via dmu_tx_hold_object()), you can not 234 * free it; it fails and returns EBUSY. 235 * 236 * If the object is not allocated, it fails and returns ENOENT. 237 * 238 * Return 0 on success, or EBUSY or ENOENT as specified above. 239 */ 240 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 241 242 /* 243 * Find the next allocated or free object. 244 * 245 * The objectp parameter is in-out. It will be updated to be the next 246 * object which is allocated. Ignore objects which have not been 247 * modified since txg. 248 * 249 * XXX Can only be called on a objset with no dirty data. 250 * 251 * Returns 0 on success, or ENOENT if there are no more objects. 252 */ 253 int dmu_object_next(objset_t *os, uint64_t *objectp, 254 boolean_t hole, uint64_t txg); 255 256 /* 257 * Set the data blocksize for an object. 258 * 259 * The object cannot have any blocks allcated beyond the first. If 260 * the first block is allocated already, the new size must be greater 261 * than the current block size. If these conditions are not met, 262 * ENOTSUP will be returned. 263 * 264 * Returns 0 on success, or EBUSY if there are any holds on the object 265 * contents, or ENOTSUP as described above. 266 */ 267 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 268 int ibs, dmu_tx_t *tx); 269 270 /* 271 * Set the checksum property on a dnode. The new checksum algorithm will 272 * apply to all newly written blocks; existing blocks will not be affected. 273 */ 274 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 275 dmu_tx_t *tx); 276 277 /* 278 * Set the compress property on a dnode. The new compression algorithm will 279 * apply to all newly written blocks; existing blocks will not be affected. 280 */ 281 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 282 dmu_tx_t *tx); 283 284 /* 285 * Decide how many copies of a given block we should make. Can be from 286 * 1 to SPA_DVAS_PER_BP. 287 */ 288 int dmu_get_replication_level(struct objset_impl *, struct zbookmark *zb, 289 dmu_object_type_t ot); 290 /* 291 * The bonus data is accessed more or less like a regular buffer. 292 * You must dmu_bonus_hold() to get the buffer, which will give you a 293 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 294 * data. As with any normal buffer, you must call dmu_buf_read() to 295 * read db_data, dmu_buf_will_dirty() before modifying it, and the 296 * object must be held in an assigned transaction before calling 297 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 298 * buffer as well. You must release your hold with dmu_buf_rele(). 299 */ 300 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 301 int dmu_bonus_max(void); 302 303 /* 304 * Obtain the DMU buffer from the specified object which contains the 305 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 306 * that it will remain in memory. You must release the hold with 307 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 308 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 309 * 310 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 311 * on the returned buffer before reading or writing the buffer's 312 * db_data. The comments for those routines describe what particular 313 * operations are valid after calling them. 314 * 315 * The object number must be a valid, allocated object number. 316 */ 317 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 318 void *tag, dmu_buf_t **); 319 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 320 void dmu_buf_rele(dmu_buf_t *db, void *tag); 321 uint64_t dmu_buf_refcount(dmu_buf_t *db); 322 323 /* 324 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 325 * range of an object. A pointer to an array of dmu_buf_t*'s is 326 * returned (in *dbpp). 327 * 328 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 329 * frees the array. The hold on the array of buffers MUST be released 330 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 331 * individually with dmu_buf_rele. 332 */ 333 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 334 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 335 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 336 337 /* 338 * Returns NULL on success, or the existing user ptr if it's already 339 * been set. 340 * 341 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 342 * 343 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 344 * will be set to db->db_data when you are allowed to access it. Note 345 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 346 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 347 * *user_data_ptr_ptr will be set to the new value when it changes. 348 * 349 * If non-NULL, pageout func will be called when this buffer is being 350 * excised from the cache, so that you can clean up the data structure 351 * pointed to by user_ptr. 352 * 353 * dmu_evict_user() will call the pageout func for all buffers in a 354 * objset with a given pageout func. 355 */ 356 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 357 dmu_buf_evict_func_t *pageout_func); 358 /* 359 * set_user_ie is the same as set_user, but request immediate eviction 360 * when hold count goes to zero. 361 */ 362 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 363 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 364 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 365 void *user_ptr, void *user_data_ptr_ptr, 366 dmu_buf_evict_func_t *pageout_func); 367 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 368 369 /* 370 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 371 */ 372 void *dmu_buf_get_user(dmu_buf_t *db); 373 374 /* 375 * Indicate that you are going to modify the buffer's data (db_data). 376 * 377 * The transaction (tx) must be assigned to a txg (ie. you've called 378 * dmu_tx_assign()). The buffer's object must be held in the tx 379 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 380 */ 381 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 382 383 /* 384 * You must create a transaction, then hold the objects which you will 385 * (or might) modify as part of this transaction. Then you must assign 386 * the transaction to a transaction group. Once the transaction has 387 * been assigned, you can modify buffers which belong to held objects as 388 * part of this transaction. You can't modify buffers before the 389 * transaction has been assigned; you can't modify buffers which don't 390 * belong to objects which this transaction holds; you can't hold 391 * objects once the transaction has been assigned. You may hold an 392 * object which you are going to free (with dmu_object_free()), but you 393 * don't have to. 394 * 395 * You can abort the transaction before it has been assigned. 396 * 397 * Note that you may hold buffers (with dmu_buf_hold) at any time, 398 * regardless of transaction state. 399 */ 400 401 #define DMU_NEW_OBJECT (-1ULL) 402 #define DMU_OBJECT_END (-1ULL) 403 404 dmu_tx_t *dmu_tx_create(objset_t *os); 405 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 406 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 407 uint64_t len); 408 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, char *name); 409 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 410 void dmu_tx_abort(dmu_tx_t *tx); 411 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); 412 void dmu_tx_wait(dmu_tx_t *tx); 413 void dmu_tx_commit(dmu_tx_t *tx); 414 415 /* 416 * Free up the data blocks for a defined range of a file. If size is 417 * zero, the range from offset to end-of-file is freed. 418 */ 419 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 420 uint64_t size, dmu_tx_t *tx); 421 422 /* 423 * Convenience functions. 424 * 425 * Canfail routines will return 0 on success, or an errno if there is a 426 * nonrecoverable I/O error. 427 */ 428 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 429 void *buf); 430 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 431 const void *buf, dmu_tx_t *tx); 432 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size); 433 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size, 434 dmu_tx_t *tx); 435 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, 436 uint64_t size, struct page *pp, dmu_tx_t *tx); 437 438 extern int zfs_prefetch_disable; 439 440 /* 441 * Asynchronously try to read in the data. 442 */ 443 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 444 uint64_t len); 445 446 typedef struct dmu_object_info { 447 /* All sizes are in bytes. */ 448 uint32_t doi_data_block_size; 449 uint32_t doi_metadata_block_size; 450 uint64_t doi_bonus_size; 451 dmu_object_type_t doi_type; 452 dmu_object_type_t doi_bonus_type; 453 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 454 uint8_t doi_checksum; 455 uint8_t doi_compress; 456 uint8_t doi_pad[5]; 457 /* Values below are number of 512-byte blocks. */ 458 uint64_t doi_physical_blks; /* data + metadata */ 459 uint64_t doi_max_block_offset; 460 } dmu_object_info_t; 461 462 typedef struct dmu_object_type_info { 463 dmu_byteswap_func_t *ot_byteswap; 464 boolean_t ot_metadata; 465 char *ot_name; 466 } dmu_object_type_info_t; 467 468 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 469 470 /* 471 * Get information on a DMU object. 472 * 473 * Return 0 on success or ENOENT if object is not allocated. 474 * 475 * If doi is NULL, just indicates whether the object exists. 476 */ 477 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 478 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 479 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 480 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 481 u_longlong_t *nblk512); 482 483 typedef struct dmu_objset_stats { 484 uint64_t dds_num_clones; /* number of clones of this */ 485 uint64_t dds_creation_txg; 486 dmu_objset_type_t dds_type; 487 uint8_t dds_is_snapshot; 488 uint8_t dds_inconsistent; 489 char dds_clone_of[MAXNAMELEN]; 490 } dmu_objset_stats_t; 491 492 /* 493 * Get stats on a dataset. 494 */ 495 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat); 496 497 /* 498 * Add entries to the nvlist for all the objset's properties. See 499 * zfs_prop_table[] and zfs(1m) for details on the properties. 500 */ 501 void dmu_objset_stats(objset_t *os, struct nvlist *nv); 502 503 /* 504 * Get the space usage statistics for statvfs(). 505 * 506 * refdbytes is the amount of space "referenced" by this objset. 507 * availbytes is the amount of space available to this objset, taking 508 * into account quotas & reservations, assuming that no other objsets 509 * use the space first. These values correspond to the 'referenced' and 510 * 'available' properties, described in the zfs(1m) manpage. 511 * 512 * usedobjs and availobjs are the number of objects currently allocated, 513 * and available. 514 */ 515 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp, 516 uint64_t *usedobjsp, uint64_t *availobjsp); 517 518 /* 519 * The fsid_guid is a 56-bit ID that can change to avoid collisions. 520 * (Contrast with the ds_guid which is a 64-bit ID that will never 521 * change, so there is a small probability that it will collide.) 522 */ 523 uint64_t dmu_objset_fsid_guid(objset_t *os); 524 525 int dmu_objset_is_snapshot(objset_t *os); 526 527 extern struct spa *dmu_objset_spa(objset_t *os); 528 extern struct zilog *dmu_objset_zil(objset_t *os); 529 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 530 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 531 extern void dmu_objset_name(objset_t *os, char *buf); 532 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 533 extern uint64_t dmu_objset_id(objset_t *os); 534 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 535 uint64_t *id, uint64_t *offp); 536 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 537 uint64_t *idp, uint64_t *offp); 538 539 /* 540 * Return the txg number for the given assigned transaction. 541 */ 542 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 543 544 /* 545 * Synchronous write. 546 * If a parent zio is provided this function initiates a write on the 547 * provided buffer as a child of the parent zio. 548 * In the absense of a parent zio, the write is completed synchronously. 549 * At write completion, blk is filled with the bp of the written block. 550 * Note that while the data covered by this function will be on stable 551 * storage when the write completes this new data does not become a 552 * permanent part of the file until the associated transaction commits. 553 */ 554 typedef void dmu_sync_cb_t(dmu_buf_t *db, void *arg); 555 int dmu_sync(struct zio *zio, dmu_buf_t *db, 556 struct blkptr *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg); 557 558 /* 559 * Find the next hole or data block in file starting at *off 560 * Return found offset in *off. Return ESRCH for end of file. 561 */ 562 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 563 uint64_t *off); 564 565 /* 566 * Initial setup and final teardown. 567 */ 568 extern void dmu_init(void); 569 extern void dmu_fini(void); 570 571 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 572 uint64_t object, uint64_t offset, int len); 573 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 574 dmu_traverse_cb_t cb, void *arg); 575 576 int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp); 577 int dmu_recvbackup(char *tosnap, struct drr_begin *drrb, uint64_t *sizep, 578 boolean_t force, struct vnode *vp, uint64_t voffset); 579 580 /* CRC64 table */ 581 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 582 extern uint64_t zfs_crc64_table[256]; 583 584 #ifdef __cplusplus 585 } 586 #endif 587 588 #endif /* _SYS_DMU_H */ 589