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 struct zbookmark; 60 struct spa; 61 62 typedef struct objset objset_t; 63 typedef struct dmu_tx dmu_tx_t; 64 typedef struct dsl_dir dsl_dir_t; 65 66 typedef enum dmu_object_type { 67 DMU_OT_NONE, 68 /* general: */ 69 DMU_OT_OBJECT_DIRECTORY, /* ZAP */ 70 DMU_OT_OBJECT_ARRAY, /* UINT64 */ 71 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */ 72 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */ 73 DMU_OT_BPLIST, /* UINT64 */ 74 DMU_OT_BPLIST_HDR, /* UINT64 */ 75 /* spa: */ 76 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */ 77 DMU_OT_SPACE_MAP, /* UINT64 */ 78 /* zil: */ 79 DMU_OT_INTENT_LOG, /* UINT64 */ 80 /* dmu: */ 81 DMU_OT_DNODE, /* DNODE */ 82 DMU_OT_OBJSET, /* OBJSET */ 83 /* dsl: */ 84 DMU_OT_DSL_DIR, /* UINT64 */ 85 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */ 86 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */ 87 DMU_OT_DSL_PROPS, /* ZAP */ 88 DMU_OT_DSL_DATASET, /* UINT64 */ 89 /* zpl: */ 90 DMU_OT_ZNODE, /* ZNODE */ 91 DMU_OT_ACL, /* ACL */ 92 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */ 93 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */ 94 DMU_OT_MASTER_NODE, /* ZAP */ 95 DMU_OT_DELETE_QUEUE, /* ZAP */ 96 /* zvol: */ 97 DMU_OT_ZVOL, /* UINT8 */ 98 DMU_OT_ZVOL_PROP, /* ZAP */ 99 /* other; for testing only! */ 100 DMU_OT_PLAIN_OTHER, /* UINT8 */ 101 DMU_OT_UINT64_OTHER, /* UINT64 */ 102 DMU_OT_ZAP_OTHER, /* ZAP */ 103 /* new object types: */ 104 DMU_OT_ERROR_LOG, /* ZAP */ 105 106 DMU_OT_NUMTYPES 107 } dmu_object_type_t; 108 109 typedef enum dmu_objset_type { 110 DMU_OST_NONE, 111 DMU_OST_META, 112 DMU_OST_ZFS, 113 DMU_OST_ZVOL, 114 DMU_OST_OTHER, /* For testing only! */ 115 DMU_OST_ANY, /* Be careful! */ 116 DMU_OST_NUMTYPES 117 } dmu_objset_type_t; 118 119 void byteswap_uint64_array(void *buf, size_t size); 120 void byteswap_uint32_array(void *buf, size_t size); 121 void byteswap_uint16_array(void *buf, size_t size); 122 void byteswap_uint8_array(void *buf, size_t size); 123 void zap_byteswap(void *buf, size_t size); 124 void zfs_acl_byteswap(void *buf, size_t size); 125 void zfs_znode_byteswap(void *buf, size_t size); 126 127 #define DS_MODE_NONE 0 /* invalid, to aid debugging */ 128 #define DS_MODE_STANDARD 1 /* normal access, no special needs */ 129 #define DS_MODE_PRIMARY 2 /* the "main" access, e.g. a mount */ 130 #define DS_MODE_EXCLUSIVE 3 /* exclusive access, e.g. to destroy */ 131 #define DS_MODE_LEVELS 4 132 #define DS_MODE_LEVEL(x) ((x) & (DS_MODE_LEVELS - 1)) 133 #define DS_MODE_READONLY 0x8 134 #define DS_MODE_IS_READONLY(x) ((x) & DS_MODE_READONLY) 135 #define DS_MODE_INCONSISTENT 0x10 136 #define DS_MODE_IS_INCONSISTENT(x) ((x) & DS_MODE_INCONSISTENT) 137 138 #define DS_FIND_SNAPSHOTS 0x01 139 140 /* 141 * The maximum number of bytes that can be accessed as part of one 142 * operation, including metadata. 143 */ 144 #define DMU_MAX_ACCESS (10<<20) /* 10MB */ 145 146 /* 147 * Public routines to create, destroy, open, and close objsets. 148 */ 149 int dmu_objset_open(const char *name, dmu_objset_type_t type, int mode, 150 objset_t **osp); 151 void dmu_objset_close(objset_t *os); 152 int dmu_objset_evict_dbufs(objset_t *os, int try); 153 int dmu_objset_create(const char *name, dmu_objset_type_t type, 154 objset_t *clone_parent, 155 void (*func)(objset_t *os, void *arg, dmu_tx_t *tx), void *arg); 156 int dmu_objset_destroy(const char *name); 157 int dmu_snapshots_destroy(char *fsname, char *snapname); 158 int dmu_objset_rollback(const char *name); 159 int dmu_objset_snapshot(char *fsname, char *snapname, boolean_t recursive); 160 int dmu_objset_rename(const char *name, const char *newname); 161 void dmu_objset_set_quota(objset_t *os, uint64_t quota); 162 uint64_t dmu_objset_get_quota(objset_t *os); 163 int dmu_objset_request_reservation(objset_t *os, uint64_t reservation); 164 int dmu_objset_find(char *name, int func(char *, void *), void *arg, 165 int flags); 166 void dmu_objset_byteswap(void *buf, size_t size); 167 168 typedef struct dmu_buf { 169 uint64_t db_object; /* object that this buffer is part of */ 170 uint64_t db_offset; /* byte offset in this object */ 171 uint64_t db_size; /* size of buffer in bytes */ 172 void *db_data; /* data in buffer */ 173 } dmu_buf_t; 174 175 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr); 176 177 /* 178 * Callback function to perform byte swapping on a block. 179 */ 180 typedef void dmu_byteswap_func_t(void *buf, size_t size); 181 182 /* 183 * The names of zap entries in the DIRECTORY_OBJECT of the MOS. 184 */ 185 #define DMU_POOL_DIRECTORY_OBJECT 1 186 #define DMU_POOL_CONFIG "config" 187 #define DMU_POOL_ROOT_DATASET "root_dataset" 188 #define DMU_POOL_SYNC_BPLIST "sync_bplist" 189 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub" 190 #define DMU_POOL_ERRLOG_LAST "errlog_last" 191 #define DMU_POOL_SPARES "spares" 192 #define DMU_POOL_DEFLATE "deflate" 193 194 /* 195 * Allocate an object from this objset. The range of object numbers 196 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode. 197 * 198 * The transaction must be assigned to a txg. The newly allocated 199 * object will be "held" in the transaction (ie. you can modify the 200 * newly allocated object in this transaction). 201 * 202 * dmu_object_alloc() chooses an object and returns it in *objectp. 203 * 204 * dmu_object_claim() allocates a specific object number. If that 205 * number is already allocated, it fails and returns EEXIST. 206 * 207 * Return 0 on success, or ENOSPC or EEXIST as specified above. 208 */ 209 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot, 210 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 211 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot, 212 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx); 213 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot, 214 int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 215 216 /* 217 * Free an object from this objset. 218 * 219 * The object's data will be freed as well (ie. you don't need to call 220 * dmu_free(object, 0, -1, tx)). 221 * 222 * The object need not be held in the transaction. 223 * 224 * If there are any holds on this object's buffers (via dmu_buf_hold()), 225 * or tx holds on the object (via dmu_tx_hold_object()), you can not 226 * free it; it fails and returns EBUSY. 227 * 228 * If the object is not allocated, it fails and returns ENOENT. 229 * 230 * Return 0 on success, or EBUSY or ENOENT as specified above. 231 */ 232 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx); 233 234 /* 235 * Find the next allocated or free object. 236 * 237 * The objectp parameter is in-out. It will be updated to be the next 238 * object which is allocated. 239 * 240 * XXX Can only be called on a objset with no dirty data. 241 * 242 * Returns 0 on success, or ENOENT if there are no more objects. 243 */ 244 int dmu_object_next(objset_t *os, uint64_t *objectp, boolean_t hole); 245 246 /* 247 * Set the data blocksize for an object. 248 * 249 * The object cannot have any blocks allcated beyond the first. If 250 * the first block is allocated already, the new size must be greater 251 * than the current block size. If these conditions are not met, 252 * ENOTSUP will be returned. 253 * 254 * Returns 0 on success, or EBUSY if there are any holds on the object 255 * contents, or ENOTSUP as described above. 256 */ 257 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, 258 int ibs, dmu_tx_t *tx); 259 260 /* 261 * Set the checksum property on a dnode. The new checksum algorithm will 262 * apply to all newly written blocks; existing blocks will not be affected. 263 */ 264 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 265 dmu_tx_t *tx); 266 267 /* 268 * Set the compress property on a dnode. The new compression algorithm will 269 * apply to all newly written blocks; existing blocks will not be affected. 270 */ 271 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 272 dmu_tx_t *tx); 273 274 /* 275 * Decide how many copies of a given block we should make. Can be from 276 * 1 to SPA_DVAS_PER_BP. 277 */ 278 int dmu_get_replication_level(struct spa *spa, struct zbookmark *zb, 279 dmu_object_type_t ot); 280 /* 281 * The bonus data is accessed more or less like a regular buffer. 282 * You must dmu_bonus_hold() to get the buffer, which will give you a 283 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus 284 * data. As with any normal buffer, you must call dmu_buf_read() to 285 * read db_data, dmu_buf_will_dirty() before modifying it, and the 286 * object must be held in an assigned transaction before calling 287 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus 288 * buffer as well. You must release your hold with dmu_buf_rele(). 289 */ 290 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **); 291 int dmu_bonus_max(void); 292 293 /* 294 * Obtain the DMU buffer from the specified object which contains the 295 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so 296 * that it will remain in memory. You must release the hold with 297 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your 298 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU. 299 * 300 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill 301 * on the returned buffer before reading or writing the buffer's 302 * db_data. The comments for those routines describe what particular 303 * operations are valid after calling them. 304 * 305 * The object number must be a valid, allocated object number. 306 */ 307 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 308 void *tag, dmu_buf_t **); 309 void dmu_buf_add_ref(dmu_buf_t *db, void* tag); 310 void dmu_buf_rele(dmu_buf_t *db, void *tag); 311 uint64_t dmu_buf_refcount(dmu_buf_t *db); 312 313 /* 314 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a 315 * range of an object. A pointer to an array of dmu_buf_t*'s is 316 * returned (in *dbpp). 317 * 318 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and 319 * frees the array. The hold on the array of buffers MUST be released 320 * with dmu_buf_rele_array. You can NOT release the hold on each buffer 321 * individually with dmu_buf_rele. 322 */ 323 int dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 324 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 325 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset, 326 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp); 327 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag); 328 329 /* 330 * Returns NULL on success, or the existing user ptr if it's already 331 * been set. 332 * 333 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user(). 334 * 335 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which 336 * will be set to db->db_data when you are allowed to access it. Note 337 * that db->db_data (the pointer) can change when you do dmu_buf_read(), 338 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill(). 339 * *user_data_ptr_ptr will be set to the new value when it changes. 340 * 341 * If non-NULL, pageout func will be called when this buffer is being 342 * excised from the cache, so that you can clean up the data structure 343 * pointed to by user_ptr. 344 * 345 * dmu_evict_user() will call the pageout func for all buffers in a 346 * objset with a given pageout func. 347 */ 348 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr, 349 dmu_buf_evict_func_t *pageout_func); 350 /* 351 * set_user_ie is the same as set_user, but request immediate eviction 352 * when hold count goes to zero. 353 */ 354 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr, 355 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func); 356 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr, 357 void *user_ptr, void *user_data_ptr_ptr, 358 dmu_buf_evict_func_t *pageout_func); 359 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func); 360 361 void dmu_buf_hold_data(dmu_buf_t *db); 362 void dmu_buf_rele_data(dmu_buf_t *db); 363 364 /* 365 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set. 366 */ 367 void *dmu_buf_get_user(dmu_buf_t *db); 368 369 /* 370 * Indicate that you are going to modify the buffer's data (db_data). 371 * 372 * The transaction (tx) must be assigned to a txg (ie. you've called 373 * dmu_tx_assign()). The buffer's object must be held in the tx 374 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)). 375 */ 376 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx); 377 378 /* 379 * You must create a transaction, then hold the objects which you will 380 * (or might) modify as part of this transaction. Then you must assign 381 * the transaction to a transaction group. Once the transaction has 382 * been assigned, you can modify buffers which belong to held objects as 383 * part of this transaction. You can't modify buffers before the 384 * transaction has been assigned; you can't modify buffers which don't 385 * belong to objects which this transaction holds; you can't hold 386 * objects once the transaction has been assigned. You may hold an 387 * object which you are going to free (with dmu_object_free()), but you 388 * don't have to. 389 * 390 * You can abort the transaction before it has been assigned. 391 * 392 * Note that you may hold buffers (with dmu_buf_hold) at any time, 393 * regardless of transaction state. 394 */ 395 396 #define DMU_NEW_OBJECT (-1ULL) 397 #define DMU_OBJECT_END (-1ULL) 398 399 dmu_tx_t *dmu_tx_create(objset_t *os); 400 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len); 401 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, 402 uint64_t len); 403 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, char *name); 404 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object); 405 void dmu_tx_abort(dmu_tx_t *tx); 406 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); 407 void dmu_tx_wait(dmu_tx_t *tx); 408 void dmu_tx_commit(dmu_tx_t *tx); 409 410 /* 411 * Free up the data blocks for a defined range of a file. If size is 412 * zero, the range from offset to end-of-file is freed. 413 */ 414 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 415 uint64_t size, dmu_tx_t *tx); 416 417 /* 418 * Convenience functions. 419 * 420 * Canfail routines will return 0 on success, or an errno if there is a 421 * nonrecoverable I/O error. 422 */ 423 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 424 void *buf); 425 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 426 const void *buf, dmu_tx_t *tx); 427 int dmu_write_uio(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 428 struct uio *uio, dmu_tx_t *tx); 429 430 /* 431 * Asynchronously try to read in the data. 432 */ 433 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, 434 uint64_t len); 435 436 typedef struct dmu_object_info { 437 /* All sizes are in bytes. */ 438 uint32_t doi_data_block_size; 439 uint32_t doi_metadata_block_size; 440 uint64_t doi_bonus_size; 441 dmu_object_type_t doi_type; 442 dmu_object_type_t doi_bonus_type; 443 uint8_t doi_indirection; /* 2 = dnode->indirect->data */ 444 uint8_t doi_checksum; 445 uint8_t doi_compress; 446 uint8_t doi_pad[5]; 447 /* Values below are number of 512-byte blocks. */ 448 uint64_t doi_physical_blks; /* data + metadata */ 449 uint64_t doi_max_block_offset; 450 } dmu_object_info_t; 451 452 typedef struct dmu_object_type_info { 453 dmu_byteswap_func_t *ot_byteswap; 454 boolean_t ot_metadata; 455 char *ot_name; 456 } dmu_object_type_info_t; 457 458 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES]; 459 460 /* 461 * Get information on a DMU object. 462 * 463 * Return 0 on success or ENOENT if object is not allocated. 464 * 465 * If doi is NULL, just indicates whether the object exists. 466 */ 467 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi); 468 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi); 469 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi); 470 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, 471 u_longlong_t *nblk512); 472 473 /* 474 * Get the maximum nonzero offset in the object (ie. this offset and all 475 * offsets following are zero). 476 * 477 * XXX Perhaps integrate this with dmu_object_info(), although that 478 * would then have to bring in the indirect blocks. 479 */ 480 uint64_t dmu_object_max_nonzero_offset(objset_t *os, uint64_t object); 481 482 typedef struct dmu_objset_stats { 483 dmu_objset_type_t dds_type; 484 uint8_t dds_is_snapshot; 485 uint8_t dds_inconsistent; 486 uint8_t dds_pad[2]; 487 488 uint64_t dds_creation_time; 489 uint64_t dds_creation_txg; 490 491 char dds_clone_of[MAXNAMELEN]; 492 493 /* How much data is there in this objset? */ 494 495 /* 496 * Space referenced, taking into account pending writes and 497 * frees. Only relavent to filesystems and snapshots (not 498 * collections). 499 */ 500 uint64_t dds_space_refd; 501 502 /* 503 * Space "used", taking into account pending writes and frees, and 504 * children's reservations (in bytes). This is the amount of 505 * space that will be freed if this and all dependent items are 506 * destroyed (eg. child datasets, objsets, and snapshots). So 507 * for snapshots, this is the amount of space unique to this 508 * snapshot. 509 */ 510 uint64_t dds_space_used; 511 512 /* 513 * Compressed and uncompressed bytes consumed. Does not take 514 * into account reservations. Used for computing compression 515 * ratio. 516 */ 517 uint64_t dds_compressed_bytes; 518 uint64_t dds_uncompressed_bytes; 519 520 /* 521 * The ds_fsid_guid is a 56-bit ID that can change to avoid 522 * collisions. The ds_guid is a 64-bit ID that will never 523 * change, so there is a small probability that it will collide. 524 */ 525 uint64_t dds_fsid_guid; 526 527 uint64_t dds_objects_used; /* number of objects used */ 528 uint64_t dds_objects_avail; /* number of objects available */ 529 530 uint64_t dds_num_clones; /* number of clones of this */ 531 532 /* The dataset's administratively-set quota, in bytes. */ 533 uint64_t dds_quota; 534 535 /* The dataset's administratively-set reservation, in bytes */ 536 uint64_t dds_reserved; 537 538 /* 539 * The amount of additional space that this dataset can consume. 540 * Takes into account quotas & reservations. 541 * (Assuming that no other datasets consume it first.) 542 */ 543 uint64_t dds_available; 544 545 /* 546 * Used for debugging purposes 547 */ 548 uint64_t dds_last_txg; 549 } dmu_objset_stats_t; 550 551 /* 552 * Get stats on a dataset. 553 */ 554 void dmu_objset_stats(objset_t *os, dmu_objset_stats_t *dds); 555 556 int dmu_objset_is_snapshot(objset_t *os); 557 558 extern struct spa *dmu_objset_spa(objset_t *os); 559 extern struct zilog *dmu_objset_zil(objset_t *os); 560 extern struct dsl_pool *dmu_objset_pool(objset_t *os); 561 extern struct dsl_dataset *dmu_objset_ds(objset_t *os); 562 extern void dmu_objset_name(objset_t *os, char *buf); 563 extern dmu_objset_type_t dmu_objset_type(objset_t *os); 564 extern uint64_t dmu_objset_id(objset_t *os); 565 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name, 566 uint64_t *id, uint64_t *offp); 567 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name, 568 uint64_t *idp, uint64_t *offp); 569 570 /* 571 * Return the txg number for the given assigned transaction. 572 */ 573 uint64_t dmu_tx_get_txg(dmu_tx_t *tx); 574 575 /* 576 * Synchronous write. 577 * If a parent zio is provided this function initiates a write on the 578 * provided buffer as a child of the parent zio. 579 * In the absense of a parent zio, the write is completed synchronously. 580 * At write completion, blk is filled with the bp of the written block. 581 * Note that while the data covered by this function will be on stable 582 * storage when the write completes this new data does not become a 583 * permanent part of the file until the associated transaction commits. 584 */ 585 typedef void dmu_sync_cb_t(dmu_buf_t *db, void *arg); 586 int dmu_sync(struct zio *zio, dmu_buf_t *db, 587 struct blkptr *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg); 588 589 /* 590 * Find the next hole or data block in file starting at *off 591 * Return found offset in *off. Return ESRCH for end of file. 592 */ 593 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, 594 uint64_t *off); 595 596 /* 597 * Initial setup and final teardown. 598 */ 599 extern void dmu_init(void); 600 extern void dmu_fini(void); 601 602 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp, 603 uint64_t object, uint64_t offset, int len); 604 void dmu_traverse_objset(objset_t *os, uint64_t txg_start, 605 dmu_traverse_cb_t cb, void *arg); 606 607 int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp); 608 int dmu_recvbackup(char *tosnap, struct drr_begin *drrb, uint64_t *sizep, 609 struct vnode *vp, uint64_t voffset); 610 611 /* CRC64 table */ 612 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ 613 extern uint64_t zfs_crc64_table[256]; 614 615 #ifdef __cplusplus 616 } 617 #endif 618 619 #endif /* _SYS_DMU_H */ 620