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 2006 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 43 #ifdef __cplusplus 44 extern "C" { 45 #endif 46 47 struct uio; 48 struct vnode; 49 struct spa; 50 struct zilog; 51 struct zio; 52 struct blkptr; 53 struct zap_cursor; 54 struct dsl_dataset; 55 struct dsl_pool; 56 struct dnode; 57 struct drr_begin; 58 struct drr_end; 59 60 typedef struct objset objset_t; 61 typedef struct dmu_tx dmu_tx_t; 62 typedef struct dsl_dir dsl_dir_t; 63 64 typedef enum dmu_object_type { 65 DMU_OT_NONE, 66 /* general: */ 67 DMU_OT_OBJECT_DIRECTORY, /* ZAP */ 68 DMU_OT_OBJECT_ARRAY, /* UINT64 */ 69 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */ 70 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */ 71 DMU_OT_BPLIST, /* UINT64 */ 72 DMU_OT_BPLIST_HDR, /* UINT64 */ 73 /* spa: */ 74 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */ 75 DMU_OT_SPACE_MAP, /* UINT64 */ 76 /* zil: */ 77 DMU_OT_INTENT_LOG, /* UINT64 */ 78 /* dmu: */ 79 DMU_OT_DNODE, /* DNODE */ 80 DMU_OT_OBJSET, /* OBJSET */ 81 /* dsl: */ 82 DMU_OT_DSL_DIR, /* UINT64 */ 83 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */ 84 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */ 85 DMU_OT_DSL_PROPS, /* ZAP */ 86 DMU_OT_DSL_DATASET, /* UINT64 */ 87 /* zpl: */ 88 DMU_OT_ZNODE, /* ZNODE */ 89 DMU_OT_ACL, /* ACL */ 90 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */ 91 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */ 92 DMU_OT_MASTER_NODE, /* ZAP */ 93 DMU_OT_DELETE_QUEUE, /* ZAP */ 94 /* zvol: */ 95 DMU_OT_ZVOL, /* UINT8 */ 96 DMU_OT_ZVOL_PROP, /* ZAP */ 97 /* other; for testing only! */ 98 DMU_OT_PLAIN_OTHER, /* UINT8 */ 99 DMU_OT_UINT64_OTHER, /* UINT64 */ 100 DMU_OT_ZAP_OTHER, /* ZAP */ 101 /* new object types: */ 102 DMU_OT_ERROR_LOG, /* ZAP */ 103 104 DMU_OT_NUMTYPES 105 } dmu_object_type_t; 106 107 typedef enum dmu_objset_type { 108 DMU_OST_NONE, 109 DMU_OST_META, 110 DMU_OST_ZFS, 111 DMU_OST_ZVOL, 112 DMU_OST_OTHER, /* For testing only! */ 113 DMU_OST_ANY, /* Be careful! */ 114 DMU_OST_NUMTYPES 115 } dmu_objset_type_t; 116 117 void byteswap_uint64_array(void *buf, size_t size); 118 void byteswap_uint32_array(void *buf, size_t size); 119 void byteswap_uint16_array(void *buf, size_t size); 120 void byteswap_uint8_array(void *buf, size_t size); 121 void zap_byteswap(void *buf, size_t size); 122 void zfs_acl_byteswap(void *buf, size_t size); 123 void zfs_znode_byteswap(void *buf, size_t size); 124 125 #define DS_MODE_NONE 0 /* invalid, to aid debugging */ 126 #define DS_MODE_STANDARD 1 /* normal access, no special needs */ 127 #define DS_MODE_PRIMARY 2 /* the "main" access, e.g. a mount */ 128 #define DS_MODE_EXCLUSIVE 3 /* exclusive access, e.g. to destroy */ 129 #define DS_MODE_LEVELS 4 130 #define DS_MODE_LEVEL(x) ((x) & (DS_MODE_LEVELS - 1)) 131 #define DS_MODE_READONLY 0x8 132 #define DS_MODE_IS_READONLY(x) ((x) & DS_MODE_READONLY) 133 #define DS_MODE_RESTORE 0x10 134 #define DS_MODE_IS_RESTORE(x) ((x) & DS_MODE_RESTORE) 135 136 #define DS_FIND_SNAPSHOTS 0x01 137 138 /* 139 * The maximum number of bytes that can be accessed as part of one 140 * operation, including metadata. 141 */ 142 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 143 144 /* 145 * Public routines to create, destroy, open, and close objsets. 146 */ 147 int dmu_objset_open(const char *name, dmu_objset_type_t type, int mode, 148 objset_t **osp); 149 void dmu_objset_close(objset_t *os); 150 int dmu_objset_evict_dbufs(objset_t *os, int try); 151 int dmu_objset_create(const char *name, dmu_objset_type_t type, 152 objset_t *clone_parent, 153 void (*func)(objset_t *os, void *arg, dmu_tx_t *tx), void *arg); 154 int dmu_objset_destroy(const char *name); 155 int dmu_objset_rollback(const char *name); 156 int dmu_objset_rename(const char *name, const char *newname); 157 void dmu_objset_set_quota(objset_t *os, uint64_t quota); 158 uint64_t dmu_objset_get_quota(objset_t *os); 159 int dmu_objset_request_reservation(objset_t *os, uint64_t reservation); 160 void dmu_objset_find(char *name, void func(char *, void *), void *arg, 161 int flags); 162 void dmu_objset_byteswap(void *buf, size_t size); 163 164 typedef struct dmu_buf { 165 uint64_t db_object; /* object that this buffer is part of */ 166 uint64_t db_offset; /* byte offset in this object */ 167 uint64_t db_size; /* size of buffer in bytes */ 168 void *db_data; /* data in buffer */ 169 } dmu_buf_t; 170 171 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 172 173 /* 174 * Callback function to perform byte swapping on a block. 175 */ 176 typedef void dmu_byteswap_func_t(void *buf, size_t size); 177 178 #define DMU_POOL_DIRECTORY_OBJECT 1 179 #define DMU_POOL_CONFIG "config" 180 #define DMU_POOL_ROOT_DATASET "root_dataset" 181 #define DMU_POOL_SYNC_BPLIST "sync_bplist" 182 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 183 #define DMU_POOL_ERRLOG_LAST "errlog_last" 184 185 /* 186 * Allocate an object from this objset. The range of object numbers 187 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 188 * 189 * The transaction must be assigned to a txg. The newly allocated 190 * object will be "held" in the transaction (ie. you can modify the 191 * newly allocated object in this transaction). 192 * 193 * dmu_object_alloc() chooses an object and returns it in *objectp. 194 * 195 * dmu_object_claim() allocates a specific object number. If that 196 * number is already allocated, it fails and returns EEXIST. 197 * 198 * Return 0 on success, or ENOSPC or EEXIST as specified above. 199 */ 200 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot, 201 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 202 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot, 203 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 204 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 205 int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 206 207 /* 208 * Free an object from this objset. 209 * 210 * The object's data will be freed as well (ie. you don't need to call 211 * dmu_free(object, 0, -1, tx)). 212 * 213 * The object need not be held in the transaction. 214 * 215 * If there are any holds on this object's buffers (via dmu_buf_hold()), 216 * or tx holds on the object (via dmu_tx_hold_object()), you can not 217 * free it; it fails and returns EBUSY. 218 * 219 * If the object is not allocated, it fails and returns ENOENT. 220 * 221 * Return 0 on success, or EBUSY or ENOENT as specified above. 222 */ 223 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 224 225 /* 226 * Find the next allocated or free object. 227 * 228 * The objectp parameter is in-out. It will be updated to be the next 229 * object which is allocated. 230 * 231 * XXX Can only be called on a objset with no dirty data. 232 * 233 * Returns 0 on success, or ENOENT if there are no more objects. 234 */ 235 int dmu_object_next(objset_t *os, uint64_t *objectp, boolean_t hole); 236 237 /* 238 * Set the data blocksize for an object. 239 * 240 * The object cannot have any blocks allcated beyond the first. If 241 * the first block is allocated already, the new size must be greater 242 * than the current block size. If these conditions are not met, 243 * ENOTSUP will be returned. 244 * 245 * Returns 0 on success, or EBUSY if there are any holds on the object 246 * contents, or ENOTSUP as described above. 247 */ 248 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 249 int ibs, dmu_tx_t *tx); 250 251 /* 252 * Set the checksum property on a dnode. The new checksum algorithm will 253 * apply to all newly written blocks; existing blocks will not be affected. 254 */ 255 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 256 dmu_tx_t *tx); 257 258 /* 259 * Set the compress property on a dnode. The new compression algorithm will 260 * apply to all newly written blocks; existing blocks will not be affected. 261 */ 262 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 263 dmu_tx_t *tx); 264 265 /* 266 * The bonus data is accessed more or less like a regular buffer. 267 * You must dmu_bonus_hold() to get the buffer, which will give you a 268 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 269 * data. As with any normal buffer, you must call dmu_buf_read() to 270 * read db_data, dmu_buf_will_dirty() before modifying it, and the 271 * object must be held in an assigned transaction before calling 272 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 273 * buffer as well. You must release your hold with dmu_buf_rele(). 274 */ 275 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 276 int dmu_bonus_max(void); 277 278 /* 279 * Obtain the DMU buffer from the specified object which contains the 280 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 281 * that it will remain in memory. You must release the hold with 282 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 283 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 284 * 285 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 286 * on the returned buffer before reading or writing the buffer's 287 * db_data. The comments for those routines describe what particular 288 * operations are valid after calling them. 289 * 290 * The object number must be a valid, allocated object number. 291 */ 292 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 293 void *tag, dmu_buf_t **); 294 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 295 void dmu_buf_rele(dmu_buf_t *db, void *tag); 296 uint64_t dmu_buf_refcount(dmu_buf_t *db); 297 298 /* 299 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 300 * range of an object. A pointer to an array of dmu_buf_t*'s is 301 * returned (in *dbpp). 302 * 303 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 304 * frees the array. The hold on the array of buffers MUST be released 305 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 306 * individually with dmu_buf_rele. 307 */ 308 int dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 309 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 310 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 311 312 /* 313 * Returns NULL on success, or the existing user ptr if it's already 314 * been set. 315 * 316 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 317 * 318 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 319 * will be set to db->db_data when you are allowed to access it. Note 320 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 321 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 322 * *user_data_ptr_ptr will be set to the new value when it changes. 323 * 324 * If non-NULL, pageout func will be called when this buffer is being 325 * excised from the cache, so that you can clean up the data structure 326 * pointed to by user_ptr. 327 * 328 * dmu_evict_user() will call the pageout func for all buffers in a 329 * objset with a given pageout func. 330 */ 331 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 332 dmu_buf_evict_func_t *pageout_func); 333 /* 334 * set_user_ie is the same as set_user, but request immediate eviction 335 * when hold count goes to zero. 336 */ 337 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 338 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 339 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 340 void *user_ptr, void *user_data_ptr_ptr, 341 dmu_buf_evict_func_t *pageout_func); 342 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 343 344 void dmu_buf_hold_data(dmu_buf_t *db); 345 void dmu_buf_rele_data(dmu_buf_t *db); 346 347 /* 348 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 349 */ 350 void *dmu_buf_get_user(dmu_buf_t *db); 351 352 /* 353 * Indicate that you are going to modify the buffer's data (db_data). 354 * 355 * The transaction (tx) must be assigned to a txg (ie. you've called 356 * dmu_tx_assign()). The buffer's object must be held in the tx 357 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 358 */ 359 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 360 361 /* 362 * You must create a transaction, then hold the objects which you will 363 * (or might) modify as part of this transaction. Then you must assign 364 * the transaction to a transaction group. Once the transaction has 365 * been assigned, you can modify buffers which belong to held objects as 366 * part of this transaction. You can't modify buffers before the 367 * transaction has been assigned; you can't modify buffers which don't 368 * belong to objects which this transaction holds; you can't hold 369 * objects once the transaction has been assigned. You may hold an 370 * object which you are going to free (with dmu_object_free()), but you 371 * don't have to. 372 * 373 * You can abort the transaction before it has been assigned. 374 * 375 * Note that you may hold buffers (with dmu_buf_hold) at any time, 376 * regardless of transaction state. 377 */ 378 379 #define DMU_NEW_OBJECT (-1ULL) 380 #define DMU_OBJECT_END (-1ULL) 381 382 dmu_tx_t *dmu_tx_create(objset_t *os); 383 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 384 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 385 uint64_t len); 386 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, char *name); 387 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 388 void dmu_tx_abort(dmu_tx_t *tx); 389 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); 390 void dmu_tx_commit(dmu_tx_t *tx); 391 392 /* 393 * Free up the data blocks for a defined range of a file. If size is 394 * zero, the range from offset to end-of-file is freed. 395 */ 396 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 397 uint64_t size, dmu_tx_t *tx); 398 399 /* 400 * Convenience functions. 401 * 402 * Canfail routines will return 0 on success, or an errno if there is a 403 * nonrecoverable I/O error. 404 */ 405 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 406 void *buf); 407 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 408 const void *buf, dmu_tx_t *tx); 409 int dmu_write_uio(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 410 struct uio *uio, dmu_tx_t *tx); 411 412 /* 413 * Asynchronously try to read in the data. 414 */ 415 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 416 uint64_t len); 417 418 typedef struct dmu_object_info { 419 /* All sizes are in bytes. */ 420 uint32_t doi_data_block_size; 421 uint32_t doi_metadata_block_size; 422 uint64_t doi_bonus_size; 423 dmu_object_type_t doi_type; 424 dmu_object_type_t doi_bonus_type; 425 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 426 uint8_t doi_checksum; 427 uint8_t doi_compress; 428 uint8_t doi_pad[5]; 429 /* Values below are number of 512-byte blocks. */ 430 uint64_t doi_physical_blks; /* data + metadata */ 431 uint64_t doi_max_block_offset; 432 } dmu_object_info_t; 433 434 typedef struct dmu_object_type_info { 435 dmu_byteswap_func_t *ot_byteswap; 436 boolean_t ot_metadata; 437 char *ot_name; 438 } dmu_object_type_info_t; 439 440 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 441 442 /* 443 * Get information on a DMU object. 444 * 445 * Return 0 on success or ENOENT if object is not allocated. 446 * 447 * If doi is NULL, just indicates whether the object exists. 448 */ 449 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 450 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 451 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 452 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 453 u_longlong_t *nblk512); 454 455 /* 456 * Get the maximum nonzero offset in the object (ie. this offset and all 457 * offsets following are zero). 458 * 459 * XXX Perhaps integrate this with dmu_object_info(), although that 460 * would then have to bring in the indirect blocks. 461 */ 462 uint64_t dmu_object_max_nonzero_offset(objset_t *os, uint64_t object); 463 464 typedef struct dmu_objset_stats { 465 dmu_objset_type_t dds_type; 466 uint8_t dds_is_snapshot; 467 uint8_t dds_pad[3]; 468 469 uint64_t dds_creation_time; 470 uint64_t dds_creation_txg; 471 472 char dds_clone_of[MAXNAMELEN]; 473 474 /* How much data is there in this objset? */ 475 476 /* 477 * Space referenced, taking into account pending writes and 478 * frees. Only relavent to filesystems and snapshots (not 479 * collections). 480 */ 481 uint64_t dds_space_refd; 482 483 /* 484 * Space "used", taking into account pending writes and frees, and 485 * children's reservations (in bytes). This is the amount of 486 * space that will be freed if this and all dependent items are 487 * destroyed (eg. child datasets, objsets, and snapshots). So 488 * for snapshots, this is the amount of space unique to this 489 * snapshot. 490 */ 491 uint64_t dds_space_used; 492 493 /* 494 * Compressed and uncompressed bytes consumed. Does not take 495 * into account reservations. Used for computing compression 496 * ratio. 497 */ 498 uint64_t dds_compressed_bytes; 499 uint64_t dds_uncompressed_bytes; 500 501 /* 502 * The ds_fsid_guid is a 56-bit ID that can change to avoid 503 * collisions. The ds_guid is a 64-bit ID that will never 504 * change, so there is a small probability that it will collide. 505 */ 506 uint64_t dds_fsid_guid; 507 508 uint64_t dds_objects_used; /* number of objects used */ 509 uint64_t dds_objects_avail; /* number of objects available */ 510 511 uint64_t dds_num_clones; /* number of clones of this */ 512 513 /* The dataset's administratively-set quota, in bytes. */ 514 uint64_t dds_quota; 515 516 /* The dataset's administratively-set reservation, in bytes */ 517 uint64_t dds_reserved; 518 519 /* 520 * The amount of additional space that this dataset can consume. 521 * Takes into account quotas & reservations. 522 * (Assuming that no other datasets consume it first.) 523 */ 524 uint64_t dds_available; 525 526 /* 527 * Used for debugging purposes 528 */ 529 uint64_t dds_last_txg; 530 } dmu_objset_stats_t; 531 532 /* 533 * Get stats on a dataset. 534 */ 535 void dmu_objset_stats(objset_t *os, dmu_objset_stats_t *dds); 536 537 int dmu_objset_is_snapshot(objset_t *os); 538 539 extern struct spa *dmu_objset_spa(objset_t *os); 540 extern struct zilog *dmu_objset_zil(objset_t *os); 541 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 542 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 543 extern void dmu_objset_name(objset_t *os, char *buf); 544 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 545 extern uint64_t dmu_objset_id(objset_t *os); 546 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 547 uint64_t *id, uint64_t *offp); 548 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 549 uint64_t *idp, uint64_t *offp); 550 551 /* 552 * Return the txg number for the given assigned transaction. 553 */ 554 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 555 556 /* 557 * Synchronous write. 558 * On success returns 0 and fills in the blk pointed at by bp. 559 * Note that while the data covered by this function will be on stable 560 * storage when the function returns this new data does not become a 561 * permanent part of the file until the associated transaction commits. 562 */ 563 int dmu_sync(objset_t *os, uint64_t object, uint64_t offset, uint64_t *blkoff, 564 struct blkptr *bp, uint64_t txg); 565 566 /* 567 * Find the next hole or data block in file starting at *off 568 * Return found offset in *off. Return ESRCH for end of file. 569 */ 570 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 571 uint64_t *off); 572 573 /* 574 * Initial setup and final teardown. 575 */ 576 extern void dmu_init(void); 577 extern void dmu_fini(void); 578 579 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 580 uint64_t object, uint64_t offset, int len); 581 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 582 dmu_traverse_cb_t cb, void *arg); 583 584 int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp); 585 int dmu_recvbackup(char *tosnap, struct drr_begin *drrb, uint64_t *sizep, 586 struct vnode *vp, uint64_t voffset); 587 588 /* CRC64 table */ 589 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 590 extern uint64_t zfs_crc64_table[256]; 591 592 #ifdef __cplusplus 593 } 594 #endif 595 596 #endif /* _SYS_DMU_H */ 597