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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2013 by Delphix. All rights reserved. 24 * Copyright (c) 2012, Joyent, Inc. All rights reserved. 25 */ 26 27 #include <sys/dmu_objset.h> 28 #include <sys/dsl_dataset.h> 29 #include <sys/dsl_dir.h> 30 #include <sys/dsl_prop.h> 31 #include <sys/dsl_synctask.h> 32 #include <sys/dmu_traverse.h> 33 #include <sys/dmu_impl.h> 34 #include <sys/dmu_tx.h> 35 #include <sys/arc.h> 36 #include <sys/zio.h> 37 #include <sys/zap.h> 38 #include <sys/zfeature.h> 39 #include <sys/unique.h> 40 #include <sys/zfs_context.h> 41 #include <sys/zfs_ioctl.h> 42 #include <sys/spa.h> 43 #include <sys/zfs_znode.h> 44 #include <sys/zfs_onexit.h> 45 #include <sys/zvol.h> 46 #include <sys/dsl_scan.h> 47 #include <sys/dsl_deadlist.h> 48 #include <sys/dsl_destroy.h> 49 #include <sys/dsl_userhold.h> 50 #include <sys/dsl_bookmark.h> 51 52 #define SWITCH64(x, y) \ 53 { \ 54 uint64_t __tmp = (x); \ 55 (x) = (y); \ 56 (y) = __tmp; \ 57 } 58 59 #define DS_REF_MAX (1ULL << 62) 60 61 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 62 63 /* 64 * Figure out how much of this delta should be propogated to the dsl_dir 65 * layer. If there's a refreservation, that space has already been 66 * partially accounted for in our ancestors. 67 */ 68 static int64_t 69 parent_delta(dsl_dataset_t *ds, int64_t delta) 70 { 71 uint64_t old_bytes, new_bytes; 72 73 if (ds->ds_reserved == 0) 74 return (delta); 75 76 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 77 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 78 79 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 80 return (new_bytes - old_bytes); 81 } 82 83 void 84 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 85 { 86 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 87 int compressed = BP_GET_PSIZE(bp); 88 int uncompressed = BP_GET_UCSIZE(bp); 89 int64_t delta; 90 91 dprintf_bp(bp, "ds=%p", ds); 92 93 ASSERT(dmu_tx_is_syncing(tx)); 94 /* It could have been compressed away to nothing */ 95 if (BP_IS_HOLE(bp)) 96 return; 97 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 98 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 99 if (ds == NULL) { 100 dsl_pool_mos_diduse_space(tx->tx_pool, 101 used, compressed, uncompressed); 102 return; 103 } 104 105 dmu_buf_will_dirty(ds->ds_dbuf, tx); 106 mutex_enter(&ds->ds_lock); 107 delta = parent_delta(ds, used); 108 ds->ds_phys->ds_referenced_bytes += used; 109 ds->ds_phys->ds_compressed_bytes += compressed; 110 ds->ds_phys->ds_uncompressed_bytes += uncompressed; 111 ds->ds_phys->ds_unique_bytes += used; 112 mutex_exit(&ds->ds_lock); 113 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 114 compressed, uncompressed, tx); 115 dsl_dir_transfer_space(ds->ds_dir, used - delta, 116 DD_USED_REFRSRV, DD_USED_HEAD, tx); 117 } 118 119 int 120 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 121 boolean_t async) 122 { 123 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 124 int compressed = BP_GET_PSIZE(bp); 125 int uncompressed = BP_GET_UCSIZE(bp); 126 127 if (BP_IS_HOLE(bp)) 128 return (0); 129 130 ASSERT(dmu_tx_is_syncing(tx)); 131 ASSERT(bp->blk_birth <= tx->tx_txg); 132 133 if (ds == NULL) { 134 dsl_free(tx->tx_pool, tx->tx_txg, bp); 135 dsl_pool_mos_diduse_space(tx->tx_pool, 136 -used, -compressed, -uncompressed); 137 return (used); 138 } 139 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 140 141 ASSERT(!dsl_dataset_is_snapshot(ds)); 142 dmu_buf_will_dirty(ds->ds_dbuf, tx); 143 144 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) { 145 int64_t delta; 146 147 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 148 dsl_free(tx->tx_pool, tx->tx_txg, bp); 149 150 mutex_enter(&ds->ds_lock); 151 ASSERT(ds->ds_phys->ds_unique_bytes >= used || 152 !DS_UNIQUE_IS_ACCURATE(ds)); 153 delta = parent_delta(ds, -used); 154 ds->ds_phys->ds_unique_bytes -= used; 155 mutex_exit(&ds->ds_lock); 156 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 157 delta, -compressed, -uncompressed, tx); 158 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 159 DD_USED_REFRSRV, DD_USED_HEAD, tx); 160 } else { 161 dprintf_bp(bp, "putting on dead list: %s", ""); 162 if (async) { 163 /* 164 * We are here as part of zio's write done callback, 165 * which means we're a zio interrupt thread. We can't 166 * call dsl_deadlist_insert() now because it may block 167 * waiting for I/O. Instead, put bp on the deferred 168 * queue and let dsl_pool_sync() finish the job. 169 */ 170 bplist_append(&ds->ds_pending_deadlist, bp); 171 } else { 172 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 173 } 174 ASSERT3U(ds->ds_prev->ds_object, ==, 175 ds->ds_phys->ds_prev_snap_obj); 176 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0); 177 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 178 if (ds->ds_prev->ds_phys->ds_next_snap_obj == 179 ds->ds_object && bp->blk_birth > 180 ds->ds_prev->ds_phys->ds_prev_snap_txg) { 181 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 182 mutex_enter(&ds->ds_prev->ds_lock); 183 ds->ds_prev->ds_phys->ds_unique_bytes += used; 184 mutex_exit(&ds->ds_prev->ds_lock); 185 } 186 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 187 dsl_dir_transfer_space(ds->ds_dir, used, 188 DD_USED_HEAD, DD_USED_SNAP, tx); 189 } 190 } 191 mutex_enter(&ds->ds_lock); 192 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used); 193 ds->ds_phys->ds_referenced_bytes -= used; 194 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed); 195 ds->ds_phys->ds_compressed_bytes -= compressed; 196 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed); 197 ds->ds_phys->ds_uncompressed_bytes -= uncompressed; 198 mutex_exit(&ds->ds_lock); 199 200 return (used); 201 } 202 203 uint64_t 204 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 205 { 206 uint64_t trysnap = 0; 207 208 if (ds == NULL) 209 return (0); 210 /* 211 * The snapshot creation could fail, but that would cause an 212 * incorrect FALSE return, which would only result in an 213 * overestimation of the amount of space that an operation would 214 * consume, which is OK. 215 * 216 * There's also a small window where we could miss a pending 217 * snapshot, because we could set the sync task in the quiescing 218 * phase. So this should only be used as a guess. 219 */ 220 if (ds->ds_trysnap_txg > 221 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 222 trysnap = ds->ds_trysnap_txg; 223 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap)); 224 } 225 226 boolean_t 227 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp, 228 uint64_t blk_birth) 229 { 230 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) || 231 (bp != NULL && BP_IS_HOLE(bp))) 232 return (B_FALSE); 233 234 ddt_prefetch(dsl_dataset_get_spa(ds), bp); 235 236 return (B_TRUE); 237 } 238 239 /* ARGSUSED */ 240 static void 241 dsl_dataset_evict(dmu_buf_t *db, void *dsv) 242 { 243 dsl_dataset_t *ds = dsv; 244 245 ASSERT(ds->ds_owner == NULL); 246 247 unique_remove(ds->ds_fsid_guid); 248 249 if (ds->ds_objset != NULL) 250 dmu_objset_evict(ds->ds_objset); 251 252 if (ds->ds_prev) { 253 dsl_dataset_rele(ds->ds_prev, ds); 254 ds->ds_prev = NULL; 255 } 256 257 bplist_destroy(&ds->ds_pending_deadlist); 258 if (ds->ds_phys->ds_deadlist_obj != 0) 259 dsl_deadlist_close(&ds->ds_deadlist); 260 if (ds->ds_dir) 261 dsl_dir_rele(ds->ds_dir, ds); 262 263 ASSERT(!list_link_active(&ds->ds_synced_link)); 264 265 mutex_destroy(&ds->ds_lock); 266 mutex_destroy(&ds->ds_opening_lock); 267 refcount_destroy(&ds->ds_longholds); 268 269 kmem_free(ds, sizeof (dsl_dataset_t)); 270 } 271 272 int 273 dsl_dataset_get_snapname(dsl_dataset_t *ds) 274 { 275 dsl_dataset_phys_t *headphys; 276 int err; 277 dmu_buf_t *headdbuf; 278 dsl_pool_t *dp = ds->ds_dir->dd_pool; 279 objset_t *mos = dp->dp_meta_objset; 280 281 if (ds->ds_snapname[0]) 282 return (0); 283 if (ds->ds_phys->ds_next_snap_obj == 0) 284 return (0); 285 286 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 287 FTAG, &headdbuf); 288 if (err != 0) 289 return (err); 290 headphys = headdbuf->db_data; 291 err = zap_value_search(dp->dp_meta_objset, 292 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 293 dmu_buf_rele(headdbuf, FTAG); 294 return (err); 295 } 296 297 int 298 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 299 { 300 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 301 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 302 matchtype_t mt; 303 int err; 304 305 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 306 mt = MT_FIRST; 307 else 308 mt = MT_EXACT; 309 310 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 311 value, mt, NULL, 0, NULL); 312 if (err == ENOTSUP && mt == MT_FIRST) 313 err = zap_lookup(mos, snapobj, name, 8, 1, value); 314 return (err); 315 } 316 317 int 318 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx) 319 { 320 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 321 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 322 matchtype_t mt; 323 int err; 324 325 dsl_dir_snap_cmtime_update(ds->ds_dir); 326 327 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 328 mt = MT_FIRST; 329 else 330 mt = MT_EXACT; 331 332 err = zap_remove_norm(mos, snapobj, name, mt, tx); 333 if (err == ENOTSUP && mt == MT_FIRST) 334 err = zap_remove(mos, snapobj, name, tx); 335 return (err); 336 } 337 338 int 339 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 340 dsl_dataset_t **dsp) 341 { 342 objset_t *mos = dp->dp_meta_objset; 343 dmu_buf_t *dbuf; 344 dsl_dataset_t *ds; 345 int err; 346 dmu_object_info_t doi; 347 348 ASSERT(dsl_pool_config_held(dp)); 349 350 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 351 if (err != 0) 352 return (err); 353 354 /* Make sure dsobj has the correct object type. */ 355 dmu_object_info_from_db(dbuf, &doi); 356 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) { 357 dmu_buf_rele(dbuf, tag); 358 return (SET_ERROR(EINVAL)); 359 } 360 361 ds = dmu_buf_get_user(dbuf); 362 if (ds == NULL) { 363 dsl_dataset_t *winner = NULL; 364 365 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 366 ds->ds_dbuf = dbuf; 367 ds->ds_object = dsobj; 368 ds->ds_phys = dbuf->db_data; 369 370 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 371 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 372 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 373 refcount_create(&ds->ds_longholds); 374 375 bplist_create(&ds->ds_pending_deadlist); 376 dsl_deadlist_open(&ds->ds_deadlist, 377 mos, ds->ds_phys->ds_deadlist_obj); 378 379 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 380 offsetof(dmu_sendarg_t, dsa_link)); 381 382 if (err == 0) { 383 err = dsl_dir_hold_obj(dp, 384 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 385 } 386 if (err != 0) { 387 mutex_destroy(&ds->ds_lock); 388 mutex_destroy(&ds->ds_opening_lock); 389 refcount_destroy(&ds->ds_longholds); 390 bplist_destroy(&ds->ds_pending_deadlist); 391 dsl_deadlist_close(&ds->ds_deadlist); 392 kmem_free(ds, sizeof (dsl_dataset_t)); 393 dmu_buf_rele(dbuf, tag); 394 return (err); 395 } 396 397 if (!dsl_dataset_is_snapshot(ds)) { 398 ds->ds_snapname[0] = '\0'; 399 if (ds->ds_phys->ds_prev_snap_obj != 0) { 400 err = dsl_dataset_hold_obj(dp, 401 ds->ds_phys->ds_prev_snap_obj, 402 ds, &ds->ds_prev); 403 } 404 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 405 int zaperr = zap_lookup(mos, ds->ds_object, 406 DS_FIELD_BOOKMARK_NAMES, 407 sizeof (ds->ds_bookmarks), 1, 408 &ds->ds_bookmarks); 409 if (zaperr != ENOENT) 410 VERIFY0(zaperr); 411 } 412 } else { 413 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 414 err = dsl_dataset_get_snapname(ds); 415 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) { 416 err = zap_count( 417 ds->ds_dir->dd_pool->dp_meta_objset, 418 ds->ds_phys->ds_userrefs_obj, 419 &ds->ds_userrefs); 420 } 421 } 422 423 if (err == 0 && !dsl_dataset_is_snapshot(ds)) { 424 err = dsl_prop_get_int_ds(ds, 425 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 426 &ds->ds_reserved); 427 if (err == 0) { 428 err = dsl_prop_get_int_ds(ds, 429 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 430 &ds->ds_quota); 431 } 432 } else { 433 ds->ds_reserved = ds->ds_quota = 0; 434 } 435 436 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds, 437 &ds->ds_phys, dsl_dataset_evict)) != NULL) { 438 bplist_destroy(&ds->ds_pending_deadlist); 439 dsl_deadlist_close(&ds->ds_deadlist); 440 if (ds->ds_prev) 441 dsl_dataset_rele(ds->ds_prev, ds); 442 dsl_dir_rele(ds->ds_dir, ds); 443 mutex_destroy(&ds->ds_lock); 444 mutex_destroy(&ds->ds_opening_lock); 445 refcount_destroy(&ds->ds_longholds); 446 kmem_free(ds, sizeof (dsl_dataset_t)); 447 if (err != 0) { 448 dmu_buf_rele(dbuf, tag); 449 return (err); 450 } 451 ds = winner; 452 } else { 453 ds->ds_fsid_guid = 454 unique_insert(ds->ds_phys->ds_fsid_guid); 455 } 456 } 457 ASSERT3P(ds->ds_dbuf, ==, dbuf); 458 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 459 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 || 460 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 461 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 462 *dsp = ds; 463 return (0); 464 } 465 466 int 467 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 468 void *tag, dsl_dataset_t **dsp) 469 { 470 dsl_dir_t *dd; 471 const char *snapname; 472 uint64_t obj; 473 int err = 0; 474 475 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 476 if (err != 0) 477 return (err); 478 479 ASSERT(dsl_pool_config_held(dp)); 480 obj = dd->dd_phys->dd_head_dataset_obj; 481 if (obj != 0) 482 err = dsl_dataset_hold_obj(dp, obj, tag, dsp); 483 else 484 err = SET_ERROR(ENOENT); 485 486 /* we may be looking for a snapshot */ 487 if (err == 0 && snapname != NULL) { 488 dsl_dataset_t *ds; 489 490 if (*snapname++ != '@') { 491 dsl_dataset_rele(*dsp, tag); 492 dsl_dir_rele(dd, FTAG); 493 return (SET_ERROR(ENOENT)); 494 } 495 496 dprintf("looking for snapshot '%s'\n", snapname); 497 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 498 if (err == 0) 499 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 500 dsl_dataset_rele(*dsp, tag); 501 502 if (err == 0) { 503 mutex_enter(&ds->ds_lock); 504 if (ds->ds_snapname[0] == 0) 505 (void) strlcpy(ds->ds_snapname, snapname, 506 sizeof (ds->ds_snapname)); 507 mutex_exit(&ds->ds_lock); 508 *dsp = ds; 509 } 510 } 511 512 dsl_dir_rele(dd, FTAG); 513 return (err); 514 } 515 516 int 517 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 518 void *tag, dsl_dataset_t **dsp) 519 { 520 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 521 if (err != 0) 522 return (err); 523 if (!dsl_dataset_tryown(*dsp, tag)) { 524 dsl_dataset_rele(*dsp, tag); 525 *dsp = NULL; 526 return (SET_ERROR(EBUSY)); 527 } 528 return (0); 529 } 530 531 int 532 dsl_dataset_own(dsl_pool_t *dp, const char *name, 533 void *tag, dsl_dataset_t **dsp) 534 { 535 int err = dsl_dataset_hold(dp, name, tag, dsp); 536 if (err != 0) 537 return (err); 538 if (!dsl_dataset_tryown(*dsp, tag)) { 539 dsl_dataset_rele(*dsp, tag); 540 return (SET_ERROR(EBUSY)); 541 } 542 return (0); 543 } 544 545 /* 546 * See the comment above dsl_pool_hold() for details. In summary, a long 547 * hold is used to prevent destruction of a dataset while the pool hold 548 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 549 * 550 * The dataset and pool must be held when this function is called. After it 551 * is called, the pool hold may be released while the dataset is still held 552 * and accessed. 553 */ 554 void 555 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 556 { 557 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 558 (void) refcount_add(&ds->ds_longholds, tag); 559 } 560 561 void 562 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 563 { 564 (void) refcount_remove(&ds->ds_longholds, tag); 565 } 566 567 /* Return B_TRUE if there are any long holds on this dataset. */ 568 boolean_t 569 dsl_dataset_long_held(dsl_dataset_t *ds) 570 { 571 return (!refcount_is_zero(&ds->ds_longholds)); 572 } 573 574 void 575 dsl_dataset_name(dsl_dataset_t *ds, char *name) 576 { 577 if (ds == NULL) { 578 (void) strcpy(name, "mos"); 579 } else { 580 dsl_dir_name(ds->ds_dir, name); 581 VERIFY0(dsl_dataset_get_snapname(ds)); 582 if (ds->ds_snapname[0]) { 583 (void) strcat(name, "@"); 584 /* 585 * We use a "recursive" mutex so that we 586 * can call dprintf_ds() with ds_lock held. 587 */ 588 if (!MUTEX_HELD(&ds->ds_lock)) { 589 mutex_enter(&ds->ds_lock); 590 (void) strcat(name, ds->ds_snapname); 591 mutex_exit(&ds->ds_lock); 592 } else { 593 (void) strcat(name, ds->ds_snapname); 594 } 595 } 596 } 597 } 598 599 void 600 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 601 { 602 dmu_buf_rele(ds->ds_dbuf, tag); 603 } 604 605 void 606 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 607 { 608 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL); 609 610 mutex_enter(&ds->ds_lock); 611 ds->ds_owner = NULL; 612 mutex_exit(&ds->ds_lock); 613 dsl_dataset_long_rele(ds, tag); 614 if (ds->ds_dbuf != NULL) 615 dsl_dataset_rele(ds, tag); 616 else 617 dsl_dataset_evict(NULL, ds); 618 } 619 620 boolean_t 621 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 622 { 623 boolean_t gotit = FALSE; 624 625 mutex_enter(&ds->ds_lock); 626 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 627 ds->ds_owner = tag; 628 dsl_dataset_long_hold(ds, tag); 629 gotit = TRUE; 630 } 631 mutex_exit(&ds->ds_lock); 632 return (gotit); 633 } 634 635 uint64_t 636 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 637 uint64_t flags, dmu_tx_t *tx) 638 { 639 dsl_pool_t *dp = dd->dd_pool; 640 dmu_buf_t *dbuf; 641 dsl_dataset_phys_t *dsphys; 642 uint64_t dsobj; 643 objset_t *mos = dp->dp_meta_objset; 644 645 if (origin == NULL) 646 origin = dp->dp_origin_snap; 647 648 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 649 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 650 ASSERT(dmu_tx_is_syncing(tx)); 651 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 652 653 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 654 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 655 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 656 dmu_buf_will_dirty(dbuf, tx); 657 dsphys = dbuf->db_data; 658 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 659 dsphys->ds_dir_obj = dd->dd_object; 660 dsphys->ds_flags = flags; 661 dsphys->ds_fsid_guid = unique_create(); 662 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 663 sizeof (dsphys->ds_guid)); 664 dsphys->ds_snapnames_zapobj = 665 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 666 DMU_OT_NONE, 0, tx); 667 dsphys->ds_creation_time = gethrestime_sec(); 668 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 669 670 if (origin == NULL) { 671 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 672 } else { 673 dsl_dataset_t *ohds; /* head of the origin snapshot */ 674 675 dsphys->ds_prev_snap_obj = origin->ds_object; 676 dsphys->ds_prev_snap_txg = 677 origin->ds_phys->ds_creation_txg; 678 dsphys->ds_referenced_bytes = 679 origin->ds_phys->ds_referenced_bytes; 680 dsphys->ds_compressed_bytes = 681 origin->ds_phys->ds_compressed_bytes; 682 dsphys->ds_uncompressed_bytes = 683 origin->ds_phys->ds_uncompressed_bytes; 684 dsphys->ds_bp = origin->ds_phys->ds_bp; 685 dsphys->ds_flags |= origin->ds_phys->ds_flags; 686 687 dmu_buf_will_dirty(origin->ds_dbuf, tx); 688 origin->ds_phys->ds_num_children++; 689 690 VERIFY0(dsl_dataset_hold_obj(dp, 691 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds)); 692 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 693 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 694 dsl_dataset_rele(ohds, FTAG); 695 696 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 697 if (origin->ds_phys->ds_next_clones_obj == 0) { 698 origin->ds_phys->ds_next_clones_obj = 699 zap_create(mos, 700 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 701 } 702 VERIFY0(zap_add_int(mos, 703 origin->ds_phys->ds_next_clones_obj, dsobj, tx)); 704 } 705 706 dmu_buf_will_dirty(dd->dd_dbuf, tx); 707 dd->dd_phys->dd_origin_obj = origin->ds_object; 708 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 709 if (origin->ds_dir->dd_phys->dd_clones == 0) { 710 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 711 origin->ds_dir->dd_phys->dd_clones = 712 zap_create(mos, 713 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 714 } 715 VERIFY0(zap_add_int(mos, 716 origin->ds_dir->dd_phys->dd_clones, dsobj, tx)); 717 } 718 } 719 720 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 721 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 722 723 dmu_buf_rele(dbuf, FTAG); 724 725 dmu_buf_will_dirty(dd->dd_dbuf, tx); 726 dd->dd_phys->dd_head_dataset_obj = dsobj; 727 728 return (dsobj); 729 } 730 731 static void 732 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 733 { 734 objset_t *os; 735 736 VERIFY0(dmu_objset_from_ds(ds, &os)); 737 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 738 dsl_dataset_dirty(ds, tx); 739 } 740 741 uint64_t 742 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 743 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 744 { 745 dsl_pool_t *dp = pdd->dd_pool; 746 uint64_t dsobj, ddobj; 747 dsl_dir_t *dd; 748 749 ASSERT(dmu_tx_is_syncing(tx)); 750 ASSERT(lastname[0] != '@'); 751 752 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 753 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 754 755 dsobj = dsl_dataset_create_sync_dd(dd, origin, 756 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 757 758 dsl_deleg_set_create_perms(dd, tx, cr); 759 760 dsl_dir_rele(dd, FTAG); 761 762 /* 763 * If we are creating a clone, make sure we zero out any stale 764 * data from the origin snapshots zil header. 765 */ 766 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 767 dsl_dataset_t *ds; 768 769 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 770 dsl_dataset_zero_zil(ds, tx); 771 dsl_dataset_rele(ds, FTAG); 772 } 773 774 return (dsobj); 775 } 776 777 /* 778 * The unique space in the head dataset can be calculated by subtracting 779 * the space used in the most recent snapshot, that is still being used 780 * in this file system, from the space currently in use. To figure out 781 * the space in the most recent snapshot still in use, we need to take 782 * the total space used in the snapshot and subtract out the space that 783 * has been freed up since the snapshot was taken. 784 */ 785 void 786 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 787 { 788 uint64_t mrs_used; 789 uint64_t dlused, dlcomp, dluncomp; 790 791 ASSERT(!dsl_dataset_is_snapshot(ds)); 792 793 if (ds->ds_phys->ds_prev_snap_obj != 0) 794 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes; 795 else 796 mrs_used = 0; 797 798 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 799 800 ASSERT3U(dlused, <=, mrs_used); 801 ds->ds_phys->ds_unique_bytes = 802 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused); 803 804 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 805 SPA_VERSION_UNIQUE_ACCURATE) 806 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 807 } 808 809 void 810 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 811 dmu_tx_t *tx) 812 { 813 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 814 uint64_t count; 815 int err; 816 817 ASSERT(ds->ds_phys->ds_num_children >= 2); 818 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx); 819 /* 820 * The err should not be ENOENT, but a bug in a previous version 821 * of the code could cause upgrade_clones_cb() to not set 822 * ds_next_snap_obj when it should, leading to a missing entry. 823 * If we knew that the pool was created after 824 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 825 * ENOENT. However, at least we can check that we don't have 826 * too many entries in the next_clones_obj even after failing to 827 * remove this one. 828 */ 829 if (err != ENOENT) 830 VERIFY0(err); 831 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 832 &count)); 833 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2); 834 } 835 836 837 blkptr_t * 838 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 839 { 840 return (&ds->ds_phys->ds_bp); 841 } 842 843 void 844 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 845 { 846 ASSERT(dmu_tx_is_syncing(tx)); 847 /* If it's the meta-objset, set dp_meta_rootbp */ 848 if (ds == NULL) { 849 tx->tx_pool->dp_meta_rootbp = *bp; 850 } else { 851 dmu_buf_will_dirty(ds->ds_dbuf, tx); 852 ds->ds_phys->ds_bp = *bp; 853 } 854 } 855 856 spa_t * 857 dsl_dataset_get_spa(dsl_dataset_t *ds) 858 { 859 return (ds->ds_dir->dd_pool->dp_spa); 860 } 861 862 void 863 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 864 { 865 dsl_pool_t *dp; 866 867 if (ds == NULL) /* this is the meta-objset */ 868 return; 869 870 ASSERT(ds->ds_objset != NULL); 871 872 if (ds->ds_phys->ds_next_snap_obj != 0) 873 panic("dirtying snapshot!"); 874 875 dp = ds->ds_dir->dd_pool; 876 877 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 878 /* up the hold count until we can be written out */ 879 dmu_buf_add_ref(ds->ds_dbuf, ds); 880 } 881 } 882 883 boolean_t 884 dsl_dataset_is_dirty(dsl_dataset_t *ds) 885 { 886 for (int t = 0; t < TXG_SIZE; t++) { 887 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 888 ds, t)) 889 return (B_TRUE); 890 } 891 return (B_FALSE); 892 } 893 894 static int 895 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 896 { 897 uint64_t asize; 898 899 if (!dmu_tx_is_syncing(tx)) 900 return (0); 901 902 /* 903 * If there's an fs-only reservation, any blocks that might become 904 * owned by the snapshot dataset must be accommodated by space 905 * outside of the reservation. 906 */ 907 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 908 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 909 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 910 return (SET_ERROR(ENOSPC)); 911 912 /* 913 * Propagate any reserved space for this snapshot to other 914 * snapshot checks in this sync group. 915 */ 916 if (asize > 0) 917 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 918 919 return (0); 920 } 921 922 typedef struct dsl_dataset_snapshot_arg { 923 nvlist_t *ddsa_snaps; 924 nvlist_t *ddsa_props; 925 nvlist_t *ddsa_errors; 926 } dsl_dataset_snapshot_arg_t; 927 928 int 929 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 930 dmu_tx_t *tx, boolean_t recv) 931 { 932 int error; 933 uint64_t value; 934 935 ds->ds_trysnap_txg = tx->tx_txg; 936 937 if (!dmu_tx_is_syncing(tx)) 938 return (0); 939 940 /* 941 * We don't allow multiple snapshots of the same txg. If there 942 * is already one, try again. 943 */ 944 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 945 return (SET_ERROR(EAGAIN)); 946 947 /* 948 * Check for conflicting snapshot name. 949 */ 950 error = dsl_dataset_snap_lookup(ds, snapname, &value); 951 if (error == 0) 952 return (SET_ERROR(EEXIST)); 953 if (error != ENOENT) 954 return (error); 955 956 /* 957 * We don't allow taking snapshots of inconsistent datasets, such as 958 * those into which we are currently receiving. However, if we are 959 * creating this snapshot as part of a receive, this check will be 960 * executed atomically with respect to the completion of the receive 961 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 962 * case we ignore this, knowing it will be fixed up for us shortly in 963 * dmu_recv_end_sync(). 964 */ 965 if (!recv && DS_IS_INCONSISTENT(ds)) 966 return (SET_ERROR(EBUSY)); 967 968 error = dsl_dataset_snapshot_reserve_space(ds, tx); 969 if (error != 0) 970 return (error); 971 972 return (0); 973 } 974 975 static int 976 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 977 { 978 dsl_dataset_snapshot_arg_t *ddsa = arg; 979 dsl_pool_t *dp = dmu_tx_pool(tx); 980 nvpair_t *pair; 981 int rv = 0; 982 983 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 984 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 985 int error = 0; 986 dsl_dataset_t *ds; 987 char *name, *atp; 988 char dsname[MAXNAMELEN]; 989 990 name = nvpair_name(pair); 991 if (strlen(name) >= MAXNAMELEN) 992 error = SET_ERROR(ENAMETOOLONG); 993 if (error == 0) { 994 atp = strchr(name, '@'); 995 if (atp == NULL) 996 error = SET_ERROR(EINVAL); 997 if (error == 0) 998 (void) strlcpy(dsname, name, atp - name + 1); 999 } 1000 if (error == 0) 1001 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1002 if (error == 0) { 1003 error = dsl_dataset_snapshot_check_impl(ds, 1004 atp + 1, tx, B_FALSE); 1005 dsl_dataset_rele(ds, FTAG); 1006 } 1007 1008 if (error != 0) { 1009 if (ddsa->ddsa_errors != NULL) { 1010 fnvlist_add_int32(ddsa->ddsa_errors, 1011 name, error); 1012 } 1013 rv = error; 1014 } 1015 } 1016 return (rv); 1017 } 1018 1019 void 1020 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1021 dmu_tx_t *tx) 1022 { 1023 static zil_header_t zero_zil; 1024 1025 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1026 dmu_buf_t *dbuf; 1027 dsl_dataset_phys_t *dsphys; 1028 uint64_t dsobj, crtxg; 1029 objset_t *mos = dp->dp_meta_objset; 1030 objset_t *os; 1031 1032 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1033 1034 /* 1035 * If we are on an old pool, the zil must not be active, in which 1036 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1037 */ 1038 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1039 dmu_objset_from_ds(ds, &os) != 0 || 1040 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1041 sizeof (zero_zil)) == 0); 1042 1043 1044 /* 1045 * The origin's ds_creation_txg has to be < TXG_INITIAL 1046 */ 1047 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1048 crtxg = 1; 1049 else 1050 crtxg = tx->tx_txg; 1051 1052 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1053 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1054 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1055 dmu_buf_will_dirty(dbuf, tx); 1056 dsphys = dbuf->db_data; 1057 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1058 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1059 dsphys->ds_fsid_guid = unique_create(); 1060 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1061 sizeof (dsphys->ds_guid)); 1062 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1063 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1064 dsphys->ds_next_snap_obj = ds->ds_object; 1065 dsphys->ds_num_children = 1; 1066 dsphys->ds_creation_time = gethrestime_sec(); 1067 dsphys->ds_creation_txg = crtxg; 1068 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1069 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes; 1070 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1071 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1072 dsphys->ds_flags = ds->ds_phys->ds_flags; 1073 dsphys->ds_bp = ds->ds_phys->ds_bp; 1074 dmu_buf_rele(dbuf, FTAG); 1075 1076 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1077 if (ds->ds_prev) { 1078 uint64_t next_clones_obj = 1079 ds->ds_prev->ds_phys->ds_next_clones_obj; 1080 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1081 ds->ds_object || 1082 ds->ds_prev->ds_phys->ds_num_children > 1); 1083 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1084 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1085 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1086 ds->ds_prev->ds_phys->ds_creation_txg); 1087 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1088 } else if (next_clones_obj != 0) { 1089 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1090 dsphys->ds_next_snap_obj, tx); 1091 VERIFY0(zap_add_int(mos, 1092 next_clones_obj, dsobj, tx)); 1093 } 1094 } 1095 1096 /* 1097 * If we have a reference-reservation on this dataset, we will 1098 * need to increase the amount of refreservation being charged 1099 * since our unique space is going to zero. 1100 */ 1101 if (ds->ds_reserved) { 1102 int64_t delta; 1103 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1104 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 1105 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1106 delta, 0, 0, tx); 1107 } 1108 1109 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1110 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist, 1111 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx); 1112 dsl_deadlist_close(&ds->ds_deadlist); 1113 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj); 1114 dsl_deadlist_add_key(&ds->ds_deadlist, 1115 ds->ds_phys->ds_prev_snap_txg, tx); 1116 1117 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1118 ds->ds_phys->ds_prev_snap_obj = dsobj; 1119 ds->ds_phys->ds_prev_snap_txg = crtxg; 1120 ds->ds_phys->ds_unique_bytes = 0; 1121 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1122 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1123 1124 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1125 snapname, 8, 1, &dsobj, tx)); 1126 1127 if (ds->ds_prev) 1128 dsl_dataset_rele(ds->ds_prev, ds); 1129 VERIFY0(dsl_dataset_hold_obj(dp, 1130 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1131 1132 dsl_scan_ds_snapshotted(ds, tx); 1133 1134 dsl_dir_snap_cmtime_update(ds->ds_dir); 1135 1136 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1137 } 1138 1139 static void 1140 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1141 { 1142 dsl_dataset_snapshot_arg_t *ddsa = arg; 1143 dsl_pool_t *dp = dmu_tx_pool(tx); 1144 nvpair_t *pair; 1145 1146 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1147 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1148 dsl_dataset_t *ds; 1149 char *name, *atp; 1150 char dsname[MAXNAMELEN]; 1151 1152 name = nvpair_name(pair); 1153 atp = strchr(name, '@'); 1154 (void) strlcpy(dsname, name, atp - name + 1); 1155 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1156 1157 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1158 if (ddsa->ddsa_props != NULL) { 1159 dsl_props_set_sync_impl(ds->ds_prev, 1160 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1161 } 1162 dsl_dataset_rele(ds, FTAG); 1163 } 1164 } 1165 1166 /* 1167 * The snapshots must all be in the same pool. 1168 * All-or-nothing: if there are any failures, nothing will be modified. 1169 */ 1170 int 1171 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1172 { 1173 dsl_dataset_snapshot_arg_t ddsa; 1174 nvpair_t *pair; 1175 boolean_t needsuspend; 1176 int error; 1177 spa_t *spa; 1178 char *firstname; 1179 nvlist_t *suspended = NULL; 1180 1181 pair = nvlist_next_nvpair(snaps, NULL); 1182 if (pair == NULL) 1183 return (0); 1184 firstname = nvpair_name(pair); 1185 1186 error = spa_open(firstname, &spa, FTAG); 1187 if (error != 0) 1188 return (error); 1189 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1190 spa_close(spa, FTAG); 1191 1192 if (needsuspend) { 1193 suspended = fnvlist_alloc(); 1194 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1195 pair = nvlist_next_nvpair(snaps, pair)) { 1196 char fsname[MAXNAMELEN]; 1197 char *snapname = nvpair_name(pair); 1198 char *atp; 1199 void *cookie; 1200 1201 atp = strchr(snapname, '@'); 1202 if (atp == NULL) { 1203 error = SET_ERROR(EINVAL); 1204 break; 1205 } 1206 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1207 1208 error = zil_suspend(fsname, &cookie); 1209 if (error != 0) 1210 break; 1211 fnvlist_add_uint64(suspended, fsname, 1212 (uintptr_t)cookie); 1213 } 1214 } 1215 1216 ddsa.ddsa_snaps = snaps; 1217 ddsa.ddsa_props = props; 1218 ddsa.ddsa_errors = errors; 1219 1220 if (error == 0) { 1221 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1222 dsl_dataset_snapshot_sync, &ddsa, 1223 fnvlist_num_pairs(snaps) * 3); 1224 } 1225 1226 if (suspended != NULL) { 1227 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1228 pair = nvlist_next_nvpair(suspended, pair)) { 1229 zil_resume((void *)(uintptr_t) 1230 fnvpair_value_uint64(pair)); 1231 } 1232 fnvlist_free(suspended); 1233 } 1234 1235 return (error); 1236 } 1237 1238 typedef struct dsl_dataset_snapshot_tmp_arg { 1239 const char *ddsta_fsname; 1240 const char *ddsta_snapname; 1241 minor_t ddsta_cleanup_minor; 1242 const char *ddsta_htag; 1243 } dsl_dataset_snapshot_tmp_arg_t; 1244 1245 static int 1246 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1247 { 1248 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1249 dsl_pool_t *dp = dmu_tx_pool(tx); 1250 dsl_dataset_t *ds; 1251 int error; 1252 1253 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1254 if (error != 0) 1255 return (error); 1256 1257 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1258 tx, B_FALSE); 1259 if (error != 0) { 1260 dsl_dataset_rele(ds, FTAG); 1261 return (error); 1262 } 1263 1264 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1265 dsl_dataset_rele(ds, FTAG); 1266 return (SET_ERROR(ENOTSUP)); 1267 } 1268 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1269 B_TRUE, tx); 1270 if (error != 0) { 1271 dsl_dataset_rele(ds, FTAG); 1272 return (error); 1273 } 1274 1275 dsl_dataset_rele(ds, FTAG); 1276 return (0); 1277 } 1278 1279 static void 1280 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1281 { 1282 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1283 dsl_pool_t *dp = dmu_tx_pool(tx); 1284 dsl_dataset_t *ds; 1285 1286 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1287 1288 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1289 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1290 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1291 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1292 1293 dsl_dataset_rele(ds, FTAG); 1294 } 1295 1296 int 1297 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1298 minor_t cleanup_minor, const char *htag) 1299 { 1300 dsl_dataset_snapshot_tmp_arg_t ddsta; 1301 int error; 1302 spa_t *spa; 1303 boolean_t needsuspend; 1304 void *cookie; 1305 1306 ddsta.ddsta_fsname = fsname; 1307 ddsta.ddsta_snapname = snapname; 1308 ddsta.ddsta_cleanup_minor = cleanup_minor; 1309 ddsta.ddsta_htag = htag; 1310 1311 error = spa_open(fsname, &spa, FTAG); 1312 if (error != 0) 1313 return (error); 1314 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1315 spa_close(spa, FTAG); 1316 1317 if (needsuspend) { 1318 error = zil_suspend(fsname, &cookie); 1319 if (error != 0) 1320 return (error); 1321 } 1322 1323 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1324 dsl_dataset_snapshot_tmp_sync, &ddsta, 3); 1325 1326 if (needsuspend) 1327 zil_resume(cookie); 1328 return (error); 1329 } 1330 1331 1332 void 1333 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1334 { 1335 ASSERT(dmu_tx_is_syncing(tx)); 1336 ASSERT(ds->ds_objset != NULL); 1337 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1338 1339 /* 1340 * in case we had to change ds_fsid_guid when we opened it, 1341 * sync it out now. 1342 */ 1343 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1344 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1345 1346 dmu_objset_sync(ds->ds_objset, zio, tx); 1347 } 1348 1349 static void 1350 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1351 { 1352 uint64_t count = 0; 1353 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1354 zap_cursor_t zc; 1355 zap_attribute_t za; 1356 nvlist_t *propval = fnvlist_alloc(); 1357 nvlist_t *val = fnvlist_alloc(); 1358 1359 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1360 1361 /* 1362 * There may be missing entries in ds_next_clones_obj 1363 * due to a bug in a previous version of the code. 1364 * Only trust it if it has the right number of entries. 1365 */ 1366 if (ds->ds_phys->ds_next_clones_obj != 0) { 1367 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 1368 &count)); 1369 } 1370 if (count != ds->ds_phys->ds_num_children - 1) 1371 goto fail; 1372 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj); 1373 zap_cursor_retrieve(&zc, &za) == 0; 1374 zap_cursor_advance(&zc)) { 1375 dsl_dataset_t *clone; 1376 char buf[ZFS_MAXNAMELEN]; 1377 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1378 za.za_first_integer, FTAG, &clone)); 1379 dsl_dir_name(clone->ds_dir, buf); 1380 fnvlist_add_boolean(val, buf); 1381 dsl_dataset_rele(clone, FTAG); 1382 } 1383 zap_cursor_fini(&zc); 1384 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1385 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1386 fail: 1387 nvlist_free(val); 1388 nvlist_free(propval); 1389 } 1390 1391 void 1392 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1393 { 1394 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1395 uint64_t refd, avail, uobjs, aobjs, ratio; 1396 1397 ASSERT(dsl_pool_config_held(dp)); 1398 1399 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1400 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1401 ds->ds_phys->ds_compressed_bytes); 1402 1403 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1404 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1405 ds->ds_phys->ds_uncompressed_bytes); 1406 1407 if (dsl_dataset_is_snapshot(ds)) { 1408 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1409 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1410 ds->ds_phys->ds_unique_bytes); 1411 get_clones_stat(ds, nv); 1412 } else { 1413 dsl_dir_stats(ds->ds_dir, nv); 1414 } 1415 1416 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1417 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1418 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1419 1420 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1421 ds->ds_phys->ds_creation_time); 1422 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1423 ds->ds_phys->ds_creation_txg); 1424 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1425 ds->ds_quota); 1426 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1427 ds->ds_reserved); 1428 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1429 ds->ds_phys->ds_guid); 1430 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1431 ds->ds_phys->ds_unique_bytes); 1432 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1433 ds->ds_object); 1434 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1435 ds->ds_userrefs); 1436 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1437 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1438 1439 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1440 uint64_t written, comp, uncomp; 1441 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1442 dsl_dataset_t *prev; 1443 1444 int err = dsl_dataset_hold_obj(dp, 1445 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev); 1446 if (err == 0) { 1447 err = dsl_dataset_space_written(prev, ds, &written, 1448 &comp, &uncomp); 1449 dsl_dataset_rele(prev, FTAG); 1450 if (err == 0) { 1451 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1452 written); 1453 } 1454 } 1455 } 1456 } 1457 1458 void 1459 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1460 { 1461 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1462 ASSERT(dsl_pool_config_held(dp)); 1463 1464 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1465 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1466 stat->dds_guid = ds->ds_phys->ds_guid; 1467 stat->dds_origin[0] = '\0'; 1468 if (dsl_dataset_is_snapshot(ds)) { 1469 stat->dds_is_snapshot = B_TRUE; 1470 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1471 } else { 1472 stat->dds_is_snapshot = B_FALSE; 1473 stat->dds_num_clones = 0; 1474 1475 if (dsl_dir_is_clone(ds->ds_dir)) { 1476 dsl_dataset_t *ods; 1477 1478 VERIFY0(dsl_dataset_hold_obj(dp, 1479 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1480 dsl_dataset_name(ods, stat->dds_origin); 1481 dsl_dataset_rele(ods, FTAG); 1482 } 1483 } 1484 } 1485 1486 uint64_t 1487 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1488 { 1489 return (ds->ds_fsid_guid); 1490 } 1491 1492 void 1493 dsl_dataset_space(dsl_dataset_t *ds, 1494 uint64_t *refdbytesp, uint64_t *availbytesp, 1495 uint64_t *usedobjsp, uint64_t *availobjsp) 1496 { 1497 *refdbytesp = ds->ds_phys->ds_referenced_bytes; 1498 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1499 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1500 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1501 if (ds->ds_quota != 0) { 1502 /* 1503 * Adjust available bytes according to refquota 1504 */ 1505 if (*refdbytesp < ds->ds_quota) 1506 *availbytesp = MIN(*availbytesp, 1507 ds->ds_quota - *refdbytesp); 1508 else 1509 *availbytesp = 0; 1510 } 1511 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1512 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1513 } 1514 1515 boolean_t 1516 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1517 { 1518 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1519 1520 ASSERT(dsl_pool_config_held(dp)); 1521 if (snap == NULL) 1522 return (B_FALSE); 1523 if (ds->ds_phys->ds_bp.blk_birth > 1524 snap->ds_phys->ds_creation_txg) { 1525 objset_t *os, *os_snap; 1526 /* 1527 * It may be that only the ZIL differs, because it was 1528 * reset in the head. Don't count that as being 1529 * modified. 1530 */ 1531 if (dmu_objset_from_ds(ds, &os) != 0) 1532 return (B_TRUE); 1533 if (dmu_objset_from_ds(snap, &os_snap) != 0) 1534 return (B_TRUE); 1535 return (bcmp(&os->os_phys->os_meta_dnode, 1536 &os_snap->os_phys->os_meta_dnode, 1537 sizeof (os->os_phys->os_meta_dnode)) != 0); 1538 } 1539 return (B_FALSE); 1540 } 1541 1542 typedef struct dsl_dataset_rename_snapshot_arg { 1543 const char *ddrsa_fsname; 1544 const char *ddrsa_oldsnapname; 1545 const char *ddrsa_newsnapname; 1546 boolean_t ddrsa_recursive; 1547 dmu_tx_t *ddrsa_tx; 1548 } dsl_dataset_rename_snapshot_arg_t; 1549 1550 /* ARGSUSED */ 1551 static int 1552 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1553 dsl_dataset_t *hds, void *arg) 1554 { 1555 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1556 int error; 1557 uint64_t val; 1558 1559 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1560 if (error != 0) { 1561 /* ignore nonexistent snapshots */ 1562 return (error == ENOENT ? 0 : error); 1563 } 1564 1565 /* new name should not exist */ 1566 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 1567 if (error == 0) 1568 error = SET_ERROR(EEXIST); 1569 else if (error == ENOENT) 1570 error = 0; 1571 1572 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1573 if (dsl_dir_namelen(hds->ds_dir) + 1 + 1574 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN) 1575 error = SET_ERROR(ENAMETOOLONG); 1576 1577 return (error); 1578 } 1579 1580 static int 1581 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 1582 { 1583 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1584 dsl_pool_t *dp = dmu_tx_pool(tx); 1585 dsl_dataset_t *hds; 1586 int error; 1587 1588 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 1589 if (error != 0) 1590 return (error); 1591 1592 if (ddrsa->ddrsa_recursive) { 1593 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1594 dsl_dataset_rename_snapshot_check_impl, ddrsa, 1595 DS_FIND_CHILDREN); 1596 } else { 1597 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 1598 } 1599 dsl_dataset_rele(hds, FTAG); 1600 return (error); 1601 } 1602 1603 static int 1604 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 1605 dsl_dataset_t *hds, void *arg) 1606 { 1607 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1608 dsl_dataset_t *ds; 1609 uint64_t val; 1610 dmu_tx_t *tx = ddrsa->ddrsa_tx; 1611 int error; 1612 1613 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1614 ASSERT(error == 0 || error == ENOENT); 1615 if (error == ENOENT) { 1616 /* ignore nonexistent snapshots */ 1617 return (0); 1618 } 1619 1620 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 1621 1622 /* log before we change the name */ 1623 spa_history_log_internal_ds(ds, "rename", tx, 1624 "-> @%s", ddrsa->ddrsa_newsnapname); 1625 1626 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx)); 1627 mutex_enter(&ds->ds_lock); 1628 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 1629 mutex_exit(&ds->ds_lock); 1630 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj, 1631 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 1632 1633 dsl_dataset_rele(ds, FTAG); 1634 return (0); 1635 } 1636 1637 static void 1638 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 1639 { 1640 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1641 dsl_pool_t *dp = dmu_tx_pool(tx); 1642 dsl_dataset_t *hds; 1643 1644 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 1645 ddrsa->ddrsa_tx = tx; 1646 if (ddrsa->ddrsa_recursive) { 1647 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1648 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 1649 DS_FIND_CHILDREN)); 1650 } else { 1651 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 1652 } 1653 dsl_dataset_rele(hds, FTAG); 1654 } 1655 1656 int 1657 dsl_dataset_rename_snapshot(const char *fsname, 1658 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 1659 { 1660 dsl_dataset_rename_snapshot_arg_t ddrsa; 1661 1662 ddrsa.ddrsa_fsname = fsname; 1663 ddrsa.ddrsa_oldsnapname = oldsnapname; 1664 ddrsa.ddrsa_newsnapname = newsnapname; 1665 ddrsa.ddrsa_recursive = recursive; 1666 1667 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 1668 dsl_dataset_rename_snapshot_sync, &ddrsa, 1)); 1669 } 1670 1671 /* 1672 * If we're doing an ownership handoff, we need to make sure that there is 1673 * only one long hold on the dataset. We're not allowed to change anything here 1674 * so we don't permanently release the long hold or regular hold here. We want 1675 * to do this only when syncing to avoid the dataset unexpectedly going away 1676 * when we release the long hold. 1677 */ 1678 static int 1679 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 1680 { 1681 boolean_t held; 1682 1683 if (!dmu_tx_is_syncing(tx)) 1684 return (0); 1685 1686 if (owner != NULL) { 1687 VERIFY3P(ds->ds_owner, ==, owner); 1688 dsl_dataset_long_rele(ds, owner); 1689 } 1690 1691 held = dsl_dataset_long_held(ds); 1692 1693 if (owner != NULL) 1694 dsl_dataset_long_hold(ds, owner); 1695 1696 if (held) 1697 return (SET_ERROR(EBUSY)); 1698 1699 return (0); 1700 } 1701 1702 typedef struct dsl_dataset_rollback_arg { 1703 const char *ddra_fsname; 1704 void *ddra_owner; 1705 nvlist_t *ddra_result; 1706 } dsl_dataset_rollback_arg_t; 1707 1708 static int 1709 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 1710 { 1711 dsl_dataset_rollback_arg_t *ddra = arg; 1712 dsl_pool_t *dp = dmu_tx_pool(tx); 1713 dsl_dataset_t *ds; 1714 int64_t unused_refres_delta; 1715 int error; 1716 1717 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 1718 if (error != 0) 1719 return (error); 1720 1721 /* must not be a snapshot */ 1722 if (dsl_dataset_is_snapshot(ds)) { 1723 dsl_dataset_rele(ds, FTAG); 1724 return (SET_ERROR(EINVAL)); 1725 } 1726 1727 /* must have a most recent snapshot */ 1728 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) { 1729 dsl_dataset_rele(ds, FTAG); 1730 return (SET_ERROR(EINVAL)); 1731 } 1732 1733 /* must not have any bookmarks after the most recent snapshot */ 1734 nvlist_t *proprequest = fnvlist_alloc(); 1735 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 1736 nvlist_t *bookmarks = fnvlist_alloc(); 1737 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks); 1738 fnvlist_free(proprequest); 1739 if (error != 0) 1740 return (error); 1741 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL); 1742 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) { 1743 nvlist_t *valuenv = 1744 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair), 1745 zfs_prop_to_name(ZFS_PROP_CREATETXG)); 1746 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value"); 1747 if (createtxg > ds->ds_phys->ds_prev_snap_txg) { 1748 fnvlist_free(bookmarks); 1749 dsl_dataset_rele(ds, FTAG); 1750 return (SET_ERROR(EEXIST)); 1751 } 1752 } 1753 fnvlist_free(bookmarks); 1754 1755 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 1756 if (error != 0) { 1757 dsl_dataset_rele(ds, FTAG); 1758 return (error); 1759 } 1760 1761 /* 1762 * Check if the snap we are rolling back to uses more than 1763 * the refquota. 1764 */ 1765 if (ds->ds_quota != 0 && 1766 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) { 1767 dsl_dataset_rele(ds, FTAG); 1768 return (SET_ERROR(EDQUOT)); 1769 } 1770 1771 /* 1772 * When we do the clone swap, we will temporarily use more space 1773 * due to the refreservation (the head will no longer have any 1774 * unique space, so the entire amount of the refreservation will need 1775 * to be free). We will immediately destroy the clone, freeing 1776 * this space, but the freeing happens over many txg's. 1777 */ 1778 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 1779 ds->ds_phys->ds_unique_bytes); 1780 1781 if (unused_refres_delta > 0 && 1782 unused_refres_delta > 1783 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 1784 dsl_dataset_rele(ds, FTAG); 1785 return (SET_ERROR(ENOSPC)); 1786 } 1787 1788 dsl_dataset_rele(ds, FTAG); 1789 return (0); 1790 } 1791 1792 static void 1793 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 1794 { 1795 dsl_dataset_rollback_arg_t *ddra = arg; 1796 dsl_pool_t *dp = dmu_tx_pool(tx); 1797 dsl_dataset_t *ds, *clone; 1798 uint64_t cloneobj; 1799 char namebuf[ZFS_MAXNAMELEN]; 1800 1801 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 1802 1803 dsl_dataset_name(ds->ds_prev, namebuf); 1804 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 1805 1806 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 1807 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 1808 1809 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 1810 1811 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 1812 dsl_dataset_zero_zil(ds, tx); 1813 1814 dsl_destroy_head_sync_impl(clone, tx); 1815 1816 dsl_dataset_rele(clone, FTAG); 1817 dsl_dataset_rele(ds, FTAG); 1818 } 1819 1820 /* 1821 * Rolls back the given filesystem or volume to the most recent snapshot. 1822 * The name of the most recent snapshot will be returned under key "target" 1823 * in the result nvlist. 1824 * 1825 * If owner != NULL: 1826 * - The existing dataset MUST be owned by the specified owner at entry 1827 * - Upon return, dataset will still be held by the same owner, whether we 1828 * succeed or not. 1829 * 1830 * This mode is required any time the existing filesystem is mounted. See 1831 * notes above zfs_suspend_fs() for further details. 1832 */ 1833 int 1834 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result) 1835 { 1836 dsl_dataset_rollback_arg_t ddra; 1837 1838 ddra.ddra_fsname = fsname; 1839 ddra.ddra_owner = owner; 1840 ddra.ddra_result = result; 1841 1842 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 1843 dsl_dataset_rollback_sync, &ddra, 1)); 1844 } 1845 1846 struct promotenode { 1847 list_node_t link; 1848 dsl_dataset_t *ds; 1849 }; 1850 1851 typedef struct dsl_dataset_promote_arg { 1852 const char *ddpa_clonename; 1853 dsl_dataset_t *ddpa_clone; 1854 list_t shared_snaps, origin_snaps, clone_snaps; 1855 dsl_dataset_t *origin_origin; /* origin of the origin */ 1856 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 1857 char *err_ds; 1858 } dsl_dataset_promote_arg_t; 1859 1860 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 1861 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 1862 void *tag); 1863 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 1864 1865 static int 1866 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 1867 { 1868 dsl_dataset_promote_arg_t *ddpa = arg; 1869 dsl_pool_t *dp = dmu_tx_pool(tx); 1870 dsl_dataset_t *hds; 1871 struct promotenode *snap; 1872 dsl_dataset_t *origin_ds; 1873 int err; 1874 uint64_t unused; 1875 1876 err = promote_hold(ddpa, dp, FTAG); 1877 if (err != 0) 1878 return (err); 1879 1880 hds = ddpa->ddpa_clone; 1881 1882 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) { 1883 promote_rele(ddpa, FTAG); 1884 return (SET_ERROR(EXDEV)); 1885 } 1886 1887 /* 1888 * Compute and check the amount of space to transfer. Since this is 1889 * so expensive, don't do the preliminary check. 1890 */ 1891 if (!dmu_tx_is_syncing(tx)) { 1892 promote_rele(ddpa, FTAG); 1893 return (0); 1894 } 1895 1896 snap = list_head(&ddpa->shared_snaps); 1897 origin_ds = snap->ds; 1898 1899 /* compute origin's new unique space */ 1900 snap = list_tail(&ddpa->clone_snaps); 1901 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 1902 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 1903 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, 1904 &ddpa->unique, &unused, &unused); 1905 1906 /* 1907 * Walk the snapshots that we are moving 1908 * 1909 * Compute space to transfer. Consider the incremental changes 1910 * to used by each snapshot: 1911 * (my used) = (prev's used) + (blocks born) - (blocks killed) 1912 * So each snapshot gave birth to: 1913 * (blocks born) = (my used) - (prev's used) + (blocks killed) 1914 * So a sequence would look like: 1915 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 1916 * Which simplifies to: 1917 * uN + kN + kN-1 + ... + k1 + k0 1918 * Note however, if we stop before we reach the ORIGIN we get: 1919 * uN + kN + kN-1 + ... + kM - uM-1 1920 */ 1921 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes; 1922 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes; 1923 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 1924 for (snap = list_head(&ddpa->shared_snaps); snap; 1925 snap = list_next(&ddpa->shared_snaps, snap)) { 1926 uint64_t val, dlused, dlcomp, dluncomp; 1927 dsl_dataset_t *ds = snap->ds; 1928 1929 /* 1930 * If there are long holds, we won't be able to evict 1931 * the objset. 1932 */ 1933 if (dsl_dataset_long_held(ds)) { 1934 err = SET_ERROR(EBUSY); 1935 goto out; 1936 } 1937 1938 /* Check that the snapshot name does not conflict */ 1939 VERIFY0(dsl_dataset_get_snapname(ds)); 1940 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 1941 if (err == 0) { 1942 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 1943 err = SET_ERROR(EEXIST); 1944 goto out; 1945 } 1946 if (err != ENOENT) 1947 goto out; 1948 1949 /* The very first snapshot does not have a deadlist */ 1950 if (ds->ds_phys->ds_prev_snap_obj == 0) 1951 continue; 1952 1953 dsl_deadlist_space(&ds->ds_deadlist, 1954 &dlused, &dlcomp, &dluncomp); 1955 ddpa->used += dlused; 1956 ddpa->comp += dlcomp; 1957 ddpa->uncomp += dluncomp; 1958 } 1959 1960 /* 1961 * If we are a clone of a clone then we never reached ORIGIN, 1962 * so we need to subtract out the clone origin's used space. 1963 */ 1964 if (ddpa->origin_origin) { 1965 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes; 1966 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes; 1967 ddpa->uncomp -= 1968 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes; 1969 } 1970 1971 /* Check that there is enough space here */ 1972 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 1973 ddpa->used); 1974 if (err != 0) 1975 goto out; 1976 1977 /* 1978 * Compute the amounts of space that will be used by snapshots 1979 * after the promotion (for both origin and clone). For each, 1980 * it is the amount of space that will be on all of their 1981 * deadlists (that was not born before their new origin). 1982 */ 1983 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 1984 uint64_t space; 1985 1986 /* 1987 * Note, typically this will not be a clone of a clone, 1988 * so dd_origin_txg will be < TXG_INITIAL, so 1989 * these snaplist_space() -> dsl_deadlist_space_range() 1990 * calls will be fast because they do not have to 1991 * iterate over all bps. 1992 */ 1993 snap = list_head(&ddpa->origin_snaps); 1994 err = snaplist_space(&ddpa->shared_snaps, 1995 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 1996 if (err != 0) 1997 goto out; 1998 1999 err = snaplist_space(&ddpa->clone_snaps, 2000 snap->ds->ds_dir->dd_origin_txg, &space); 2001 if (err != 0) 2002 goto out; 2003 ddpa->cloneusedsnap += space; 2004 } 2005 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2006 err = snaplist_space(&ddpa->origin_snaps, 2007 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap); 2008 if (err != 0) 2009 goto out; 2010 } 2011 2012 out: 2013 promote_rele(ddpa, FTAG); 2014 return (err); 2015 } 2016 2017 static void 2018 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2019 { 2020 dsl_dataset_promote_arg_t *ddpa = arg; 2021 dsl_pool_t *dp = dmu_tx_pool(tx); 2022 dsl_dataset_t *hds; 2023 struct promotenode *snap; 2024 dsl_dataset_t *origin_ds; 2025 dsl_dataset_t *origin_head; 2026 dsl_dir_t *dd; 2027 dsl_dir_t *odd = NULL; 2028 uint64_t oldnext_obj; 2029 int64_t delta; 2030 2031 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2032 hds = ddpa->ddpa_clone; 2033 2034 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE); 2035 2036 snap = list_head(&ddpa->shared_snaps); 2037 origin_ds = snap->ds; 2038 dd = hds->ds_dir; 2039 2040 snap = list_head(&ddpa->origin_snaps); 2041 origin_head = snap->ds; 2042 2043 /* 2044 * We need to explicitly open odd, since origin_ds's dd will be 2045 * changing. 2046 */ 2047 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2048 NULL, FTAG, &odd)); 2049 2050 /* change origin's next snap */ 2051 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2052 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2053 snap = list_tail(&ddpa->clone_snaps); 2054 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2055 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2056 2057 /* change the origin's next clone */ 2058 if (origin_ds->ds_phys->ds_next_clones_obj) { 2059 dsl_dataset_remove_from_next_clones(origin_ds, 2060 snap->ds->ds_object, tx); 2061 VERIFY0(zap_add_int(dp->dp_meta_objset, 2062 origin_ds->ds_phys->ds_next_clones_obj, 2063 oldnext_obj, tx)); 2064 } 2065 2066 /* change origin */ 2067 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2068 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2069 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2070 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2071 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2072 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2073 origin_head->ds_dir->dd_origin_txg = 2074 origin_ds->ds_phys->ds_creation_txg; 2075 2076 /* change dd_clone entries */ 2077 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2078 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2079 odd->dd_phys->dd_clones, hds->ds_object, tx)); 2080 VERIFY0(zap_add_int(dp->dp_meta_objset, 2081 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2082 hds->ds_object, tx)); 2083 2084 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2085 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2086 origin_head->ds_object, tx)); 2087 if (dd->dd_phys->dd_clones == 0) { 2088 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset, 2089 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 2090 } 2091 VERIFY0(zap_add_int(dp->dp_meta_objset, 2092 dd->dd_phys->dd_clones, origin_head->ds_object, tx)); 2093 } 2094 2095 /* move snapshots to this dir */ 2096 for (snap = list_head(&ddpa->shared_snaps); snap; 2097 snap = list_next(&ddpa->shared_snaps, snap)) { 2098 dsl_dataset_t *ds = snap->ds; 2099 2100 /* 2101 * Property callbacks are registered to a particular 2102 * dsl_dir. Since ours is changing, evict the objset 2103 * so that they will be unregistered from the old dsl_dir. 2104 */ 2105 if (ds->ds_objset) { 2106 dmu_objset_evict(ds->ds_objset); 2107 ds->ds_objset = NULL; 2108 } 2109 2110 /* move snap name entry */ 2111 VERIFY0(dsl_dataset_get_snapname(ds)); 2112 VERIFY0(dsl_dataset_snap_remove(origin_head, 2113 ds->ds_snapname, tx)); 2114 VERIFY0(zap_add(dp->dp_meta_objset, 2115 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2116 8, 1, &ds->ds_object, tx)); 2117 2118 /* change containing dsl_dir */ 2119 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2120 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2121 ds->ds_phys->ds_dir_obj = dd->dd_object; 2122 ASSERT3P(ds->ds_dir, ==, odd); 2123 dsl_dir_rele(ds->ds_dir, ds); 2124 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2125 NULL, ds, &ds->ds_dir)); 2126 2127 /* move any clone references */ 2128 if (ds->ds_phys->ds_next_clones_obj && 2129 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2130 zap_cursor_t zc; 2131 zap_attribute_t za; 2132 2133 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2134 ds->ds_phys->ds_next_clones_obj); 2135 zap_cursor_retrieve(&zc, &za) == 0; 2136 zap_cursor_advance(&zc)) { 2137 dsl_dataset_t *cnds; 2138 uint64_t o; 2139 2140 if (za.za_first_integer == oldnext_obj) { 2141 /* 2142 * We've already moved the 2143 * origin's reference. 2144 */ 2145 continue; 2146 } 2147 2148 VERIFY0(dsl_dataset_hold_obj(dp, 2149 za.za_first_integer, FTAG, &cnds)); 2150 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj; 2151 2152 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2153 odd->dd_phys->dd_clones, o, tx)); 2154 VERIFY0(zap_add_int(dp->dp_meta_objset, 2155 dd->dd_phys->dd_clones, o, tx)); 2156 dsl_dataset_rele(cnds, FTAG); 2157 } 2158 zap_cursor_fini(&zc); 2159 } 2160 2161 ASSERT(!dsl_prop_hascb(ds)); 2162 } 2163 2164 /* 2165 * Change space accounting. 2166 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2167 * both be valid, or both be 0 (resulting in delta == 0). This 2168 * is true for each of {clone,origin} independently. 2169 */ 2170 2171 delta = ddpa->cloneusedsnap - 2172 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2173 ASSERT3S(delta, >=, 0); 2174 ASSERT3U(ddpa->used, >=, delta); 2175 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2176 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2177 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2178 2179 delta = ddpa->originusedsnap - 2180 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2181 ASSERT3S(delta, <=, 0); 2182 ASSERT3U(ddpa->used, >=, -delta); 2183 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2184 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2185 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2186 2187 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique; 2188 2189 /* log history record */ 2190 spa_history_log_internal_ds(hds, "promote", tx, ""); 2191 2192 dsl_dir_rele(odd, FTAG); 2193 promote_rele(ddpa, FTAG); 2194 } 2195 2196 /* 2197 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2198 * (exclusive) and last_obj (inclusive). The list will be in reverse 2199 * order (last_obj will be the list_head()). If first_obj == 0, do all 2200 * snapshots back to this dataset's origin. 2201 */ 2202 static int 2203 snaplist_make(dsl_pool_t *dp, 2204 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2205 { 2206 uint64_t obj = last_obj; 2207 2208 list_create(l, sizeof (struct promotenode), 2209 offsetof(struct promotenode, link)); 2210 2211 while (obj != first_obj) { 2212 dsl_dataset_t *ds; 2213 struct promotenode *snap; 2214 int err; 2215 2216 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2217 ASSERT(err != ENOENT); 2218 if (err != 0) 2219 return (err); 2220 2221 if (first_obj == 0) 2222 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2223 2224 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2225 snap->ds = ds; 2226 list_insert_tail(l, snap); 2227 obj = ds->ds_phys->ds_prev_snap_obj; 2228 } 2229 2230 return (0); 2231 } 2232 2233 static int 2234 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2235 { 2236 struct promotenode *snap; 2237 2238 *spacep = 0; 2239 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2240 uint64_t used, comp, uncomp; 2241 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2242 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2243 *spacep += used; 2244 } 2245 return (0); 2246 } 2247 2248 static void 2249 snaplist_destroy(list_t *l, void *tag) 2250 { 2251 struct promotenode *snap; 2252 2253 if (l == NULL || !list_link_active(&l->list_head)) 2254 return; 2255 2256 while ((snap = list_tail(l)) != NULL) { 2257 list_remove(l, snap); 2258 dsl_dataset_rele(snap->ds, tag); 2259 kmem_free(snap, sizeof (*snap)); 2260 } 2261 list_destroy(l); 2262 } 2263 2264 static int 2265 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2266 { 2267 int error; 2268 dsl_dir_t *dd; 2269 struct promotenode *snap; 2270 2271 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2272 &ddpa->ddpa_clone); 2273 if (error != 0) 2274 return (error); 2275 dd = ddpa->ddpa_clone->ds_dir; 2276 2277 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) || 2278 !dsl_dir_is_clone(dd)) { 2279 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2280 return (SET_ERROR(EINVAL)); 2281 } 2282 2283 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj, 2284 &ddpa->shared_snaps, tag); 2285 if (error != 0) 2286 goto out; 2287 2288 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2289 &ddpa->clone_snaps, tag); 2290 if (error != 0) 2291 goto out; 2292 2293 snap = list_head(&ddpa->shared_snaps); 2294 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2295 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj, 2296 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, 2297 &ddpa->origin_snaps, tag); 2298 if (error != 0) 2299 goto out; 2300 2301 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) { 2302 error = dsl_dataset_hold_obj(dp, 2303 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2304 tag, &ddpa->origin_origin); 2305 if (error != 0) 2306 goto out; 2307 } 2308 out: 2309 if (error != 0) 2310 promote_rele(ddpa, tag); 2311 return (error); 2312 } 2313 2314 static void 2315 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2316 { 2317 snaplist_destroy(&ddpa->shared_snaps, tag); 2318 snaplist_destroy(&ddpa->clone_snaps, tag); 2319 snaplist_destroy(&ddpa->origin_snaps, tag); 2320 if (ddpa->origin_origin != NULL) 2321 dsl_dataset_rele(ddpa->origin_origin, tag); 2322 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2323 } 2324 2325 /* 2326 * Promote a clone. 2327 * 2328 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2329 * in with the name. (It must be at least MAXNAMELEN bytes long.) 2330 */ 2331 int 2332 dsl_dataset_promote(const char *name, char *conflsnap) 2333 { 2334 dsl_dataset_promote_arg_t ddpa = { 0 }; 2335 uint64_t numsnaps; 2336 int error; 2337 objset_t *os; 2338 2339 /* 2340 * We will modify space proportional to the number of 2341 * snapshots. Compute numsnaps. 2342 */ 2343 error = dmu_objset_hold(name, FTAG, &os); 2344 if (error != 0) 2345 return (error); 2346 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2347 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps); 2348 dmu_objset_rele(os, FTAG); 2349 if (error != 0) 2350 return (error); 2351 2352 ddpa.ddpa_clonename = name; 2353 ddpa.err_ds = conflsnap; 2354 2355 return (dsl_sync_task(name, dsl_dataset_promote_check, 2356 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps)); 2357 } 2358 2359 int 2360 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2361 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2362 { 2363 int64_t unused_refres_delta; 2364 2365 /* they should both be heads */ 2366 if (dsl_dataset_is_snapshot(clone) || 2367 dsl_dataset_is_snapshot(origin_head)) 2368 return (SET_ERROR(EINVAL)); 2369 2370 /* if we are not forcing, the branch point should be just before them */ 2371 if (!force && clone->ds_prev != origin_head->ds_prev) 2372 return (SET_ERROR(EINVAL)); 2373 2374 /* clone should be the clone (unless they are unrelated) */ 2375 if (clone->ds_prev != NULL && 2376 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2377 origin_head->ds_dir != clone->ds_prev->ds_dir) 2378 return (SET_ERROR(EINVAL)); 2379 2380 /* the clone should be a child of the origin */ 2381 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2382 return (SET_ERROR(EINVAL)); 2383 2384 /* origin_head shouldn't be modified unless 'force' */ 2385 if (!force && 2386 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2387 return (SET_ERROR(ETXTBSY)); 2388 2389 /* origin_head should have no long holds (e.g. is not mounted) */ 2390 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2391 return (SET_ERROR(EBUSY)); 2392 2393 /* check amount of any unconsumed refreservation */ 2394 unused_refres_delta = 2395 (int64_t)MIN(origin_head->ds_reserved, 2396 origin_head->ds_phys->ds_unique_bytes) - 2397 (int64_t)MIN(origin_head->ds_reserved, 2398 clone->ds_phys->ds_unique_bytes); 2399 2400 if (unused_refres_delta > 0 && 2401 unused_refres_delta > 2402 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2403 return (SET_ERROR(ENOSPC)); 2404 2405 /* clone can't be over the head's refquota */ 2406 if (origin_head->ds_quota != 0 && 2407 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota) 2408 return (SET_ERROR(EDQUOT)); 2409 2410 return (0); 2411 } 2412 2413 void 2414 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2415 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2416 { 2417 dsl_pool_t *dp = dmu_tx_pool(tx); 2418 int64_t unused_refres_delta; 2419 2420 ASSERT(clone->ds_reserved == 0); 2421 ASSERT(origin_head->ds_quota == 0 || 2422 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota); 2423 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2424 2425 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2426 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2427 2428 if (clone->ds_objset != NULL) { 2429 dmu_objset_evict(clone->ds_objset); 2430 clone->ds_objset = NULL; 2431 } 2432 2433 if (origin_head->ds_objset != NULL) { 2434 dmu_objset_evict(origin_head->ds_objset); 2435 origin_head->ds_objset = NULL; 2436 } 2437 2438 unused_refres_delta = 2439 (int64_t)MIN(origin_head->ds_reserved, 2440 origin_head->ds_phys->ds_unique_bytes) - 2441 (int64_t)MIN(origin_head->ds_reserved, 2442 clone->ds_phys->ds_unique_bytes); 2443 2444 /* 2445 * Reset origin's unique bytes, if it exists. 2446 */ 2447 if (clone->ds_prev) { 2448 dsl_dataset_t *origin = clone->ds_prev; 2449 uint64_t comp, uncomp; 2450 2451 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2452 dsl_deadlist_space_range(&clone->ds_deadlist, 2453 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2454 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp); 2455 } 2456 2457 /* swap blkptrs */ 2458 { 2459 blkptr_t tmp; 2460 tmp = origin_head->ds_phys->ds_bp; 2461 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp; 2462 clone->ds_phys->ds_bp = tmp; 2463 } 2464 2465 /* set dd_*_bytes */ 2466 { 2467 int64_t dused, dcomp, duncomp; 2468 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2469 uint64_t odl_used, odl_comp, odl_uncomp; 2470 2471 ASSERT3U(clone->ds_dir->dd_phys-> 2472 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2473 2474 dsl_deadlist_space(&clone->ds_deadlist, 2475 &cdl_used, &cdl_comp, &cdl_uncomp); 2476 dsl_deadlist_space(&origin_head->ds_deadlist, 2477 &odl_used, &odl_comp, &odl_uncomp); 2478 2479 dused = clone->ds_phys->ds_referenced_bytes + cdl_used - 2480 (origin_head->ds_phys->ds_referenced_bytes + odl_used); 2481 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp - 2482 (origin_head->ds_phys->ds_compressed_bytes + odl_comp); 2483 duncomp = clone->ds_phys->ds_uncompressed_bytes + 2484 cdl_uncomp - 2485 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2486 2487 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 2488 dused, dcomp, duncomp, tx); 2489 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 2490 -dused, -dcomp, -duncomp, tx); 2491 2492 /* 2493 * The difference in the space used by snapshots is the 2494 * difference in snapshot space due to the head's 2495 * deadlist (since that's the only thing that's 2496 * changing that affects the snapused). 2497 */ 2498 dsl_deadlist_space_range(&clone->ds_deadlist, 2499 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2500 &cdl_used, &cdl_comp, &cdl_uncomp); 2501 dsl_deadlist_space_range(&origin_head->ds_deadlist, 2502 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2503 &odl_used, &odl_comp, &odl_uncomp); 2504 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 2505 DD_USED_HEAD, DD_USED_SNAP, tx); 2506 } 2507 2508 /* swap ds_*_bytes */ 2509 SWITCH64(origin_head->ds_phys->ds_referenced_bytes, 2510 clone->ds_phys->ds_referenced_bytes); 2511 SWITCH64(origin_head->ds_phys->ds_compressed_bytes, 2512 clone->ds_phys->ds_compressed_bytes); 2513 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes, 2514 clone->ds_phys->ds_uncompressed_bytes); 2515 SWITCH64(origin_head->ds_phys->ds_unique_bytes, 2516 clone->ds_phys->ds_unique_bytes); 2517 2518 /* apply any parent delta for change in unconsumed refreservation */ 2519 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 2520 unused_refres_delta, 0, 0, tx); 2521 2522 /* 2523 * Swap deadlists. 2524 */ 2525 dsl_deadlist_close(&clone->ds_deadlist); 2526 dsl_deadlist_close(&origin_head->ds_deadlist); 2527 SWITCH64(origin_head->ds_phys->ds_deadlist_obj, 2528 clone->ds_phys->ds_deadlist_obj); 2529 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 2530 clone->ds_phys->ds_deadlist_obj); 2531 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 2532 origin_head->ds_phys->ds_deadlist_obj); 2533 2534 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 2535 2536 spa_history_log_internal_ds(clone, "clone swap", tx, 2537 "parent=%s", origin_head->ds_dir->dd_myname); 2538 } 2539 2540 /* 2541 * Given a pool name and a dataset object number in that pool, 2542 * return the name of that dataset. 2543 */ 2544 int 2545 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2546 { 2547 dsl_pool_t *dp; 2548 dsl_dataset_t *ds; 2549 int error; 2550 2551 error = dsl_pool_hold(pname, FTAG, &dp); 2552 if (error != 0) 2553 return (error); 2554 2555 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 2556 if (error == 0) { 2557 dsl_dataset_name(ds, buf); 2558 dsl_dataset_rele(ds, FTAG); 2559 } 2560 dsl_pool_rele(dp, FTAG); 2561 2562 return (error); 2563 } 2564 2565 int 2566 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2567 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2568 { 2569 int error = 0; 2570 2571 ASSERT3S(asize, >, 0); 2572 2573 /* 2574 * *ref_rsrv is the portion of asize that will come from any 2575 * unconsumed refreservation space. 2576 */ 2577 *ref_rsrv = 0; 2578 2579 mutex_enter(&ds->ds_lock); 2580 /* 2581 * Make a space adjustment for reserved bytes. 2582 */ 2583 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2584 ASSERT3U(*used, >=, 2585 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2586 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2587 *ref_rsrv = 2588 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2589 } 2590 2591 if (!check_quota || ds->ds_quota == 0) { 2592 mutex_exit(&ds->ds_lock); 2593 return (0); 2594 } 2595 /* 2596 * If they are requesting more space, and our current estimate 2597 * is over quota, they get to try again unless the actual 2598 * on-disk is over quota and there are no pending changes (which 2599 * may free up space for us). 2600 */ 2601 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) { 2602 if (inflight > 0 || 2603 ds->ds_phys->ds_referenced_bytes < ds->ds_quota) 2604 error = SET_ERROR(ERESTART); 2605 else 2606 error = SET_ERROR(EDQUOT); 2607 } 2608 mutex_exit(&ds->ds_lock); 2609 2610 return (error); 2611 } 2612 2613 typedef struct dsl_dataset_set_qr_arg { 2614 const char *ddsqra_name; 2615 zprop_source_t ddsqra_source; 2616 uint64_t ddsqra_value; 2617 } dsl_dataset_set_qr_arg_t; 2618 2619 2620 /* ARGSUSED */ 2621 static int 2622 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 2623 { 2624 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2625 dsl_pool_t *dp = dmu_tx_pool(tx); 2626 dsl_dataset_t *ds; 2627 int error; 2628 uint64_t newval; 2629 2630 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 2631 return (SET_ERROR(ENOTSUP)); 2632 2633 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2634 if (error != 0) 2635 return (error); 2636 2637 if (dsl_dataset_is_snapshot(ds)) { 2638 dsl_dataset_rele(ds, FTAG); 2639 return (SET_ERROR(EINVAL)); 2640 } 2641 2642 error = dsl_prop_predict(ds->ds_dir, 2643 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2644 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2645 if (error != 0) { 2646 dsl_dataset_rele(ds, FTAG); 2647 return (error); 2648 } 2649 2650 if (newval == 0) { 2651 dsl_dataset_rele(ds, FTAG); 2652 return (0); 2653 } 2654 2655 if (newval < ds->ds_phys->ds_referenced_bytes || 2656 newval < ds->ds_reserved) { 2657 dsl_dataset_rele(ds, FTAG); 2658 return (SET_ERROR(ENOSPC)); 2659 } 2660 2661 dsl_dataset_rele(ds, FTAG); 2662 return (0); 2663 } 2664 2665 static void 2666 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 2667 { 2668 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2669 dsl_pool_t *dp = dmu_tx_pool(tx); 2670 dsl_dataset_t *ds; 2671 uint64_t newval; 2672 2673 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2674 2675 dsl_prop_set_sync_impl(ds, 2676 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2677 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 2678 &ddsqra->ddsqra_value, tx); 2679 2680 VERIFY0(dsl_prop_get_int_ds(ds, 2681 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 2682 2683 if (ds->ds_quota != newval) { 2684 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2685 ds->ds_quota = newval; 2686 } 2687 dsl_dataset_rele(ds, FTAG); 2688 } 2689 2690 int 2691 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 2692 uint64_t refquota) 2693 { 2694 dsl_dataset_set_qr_arg_t ddsqra; 2695 2696 ddsqra.ddsqra_name = dsname; 2697 ddsqra.ddsqra_source = source; 2698 ddsqra.ddsqra_value = refquota; 2699 2700 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 2701 dsl_dataset_set_refquota_sync, &ddsqra, 0)); 2702 } 2703 2704 static int 2705 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 2706 { 2707 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2708 dsl_pool_t *dp = dmu_tx_pool(tx); 2709 dsl_dataset_t *ds; 2710 int error; 2711 uint64_t newval, unique; 2712 2713 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 2714 return (SET_ERROR(ENOTSUP)); 2715 2716 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2717 if (error != 0) 2718 return (error); 2719 2720 if (dsl_dataset_is_snapshot(ds)) { 2721 dsl_dataset_rele(ds, FTAG); 2722 return (SET_ERROR(EINVAL)); 2723 } 2724 2725 error = dsl_prop_predict(ds->ds_dir, 2726 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2727 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2728 if (error != 0) { 2729 dsl_dataset_rele(ds, FTAG); 2730 return (error); 2731 } 2732 2733 /* 2734 * If we are doing the preliminary check in open context, the 2735 * space estimates may be inaccurate. 2736 */ 2737 if (!dmu_tx_is_syncing(tx)) { 2738 dsl_dataset_rele(ds, FTAG); 2739 return (0); 2740 } 2741 2742 mutex_enter(&ds->ds_lock); 2743 if (!DS_UNIQUE_IS_ACCURATE(ds)) 2744 dsl_dataset_recalc_head_uniq(ds); 2745 unique = ds->ds_phys->ds_unique_bytes; 2746 mutex_exit(&ds->ds_lock); 2747 2748 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 2749 uint64_t delta = MAX(unique, newval) - 2750 MAX(unique, ds->ds_reserved); 2751 2752 if (delta > 2753 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 2754 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 2755 dsl_dataset_rele(ds, FTAG); 2756 return (SET_ERROR(ENOSPC)); 2757 } 2758 } 2759 2760 dsl_dataset_rele(ds, FTAG); 2761 return (0); 2762 } 2763 2764 void 2765 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 2766 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 2767 { 2768 uint64_t newval; 2769 uint64_t unique; 2770 int64_t delta; 2771 2772 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2773 source, sizeof (value), 1, &value, tx); 2774 2775 VERIFY0(dsl_prop_get_int_ds(ds, 2776 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 2777 2778 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2779 mutex_enter(&ds->ds_dir->dd_lock); 2780 mutex_enter(&ds->ds_lock); 2781 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 2782 unique = ds->ds_phys->ds_unique_bytes; 2783 delta = MAX(0, (int64_t)(newval - unique)) - 2784 MAX(0, (int64_t)(ds->ds_reserved - unique)); 2785 ds->ds_reserved = newval; 2786 mutex_exit(&ds->ds_lock); 2787 2788 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 2789 mutex_exit(&ds->ds_dir->dd_lock); 2790 } 2791 2792 static void 2793 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 2794 { 2795 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2796 dsl_pool_t *dp = dmu_tx_pool(tx); 2797 dsl_dataset_t *ds; 2798 2799 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2800 dsl_dataset_set_refreservation_sync_impl(ds, 2801 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 2802 dsl_dataset_rele(ds, FTAG); 2803 } 2804 2805 int 2806 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 2807 uint64_t refreservation) 2808 { 2809 dsl_dataset_set_qr_arg_t ddsqra; 2810 2811 ddsqra.ddsqra_name = dsname; 2812 ddsqra.ddsqra_source = source; 2813 ddsqra.ddsqra_value = refreservation; 2814 2815 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 2816 dsl_dataset_set_refreservation_sync, &ddsqra, 0)); 2817 } 2818 2819 /* 2820 * Return (in *usedp) the amount of space written in new that is not 2821 * present in oldsnap. New may be a snapshot or the head. Old must be 2822 * a snapshot before new, in new's filesystem (or its origin). If not then 2823 * fail and return EINVAL. 2824 * 2825 * The written space is calculated by considering two components: First, we 2826 * ignore any freed space, and calculate the written as new's used space 2827 * minus old's used space. Next, we add in the amount of space that was freed 2828 * between the two snapshots, thus reducing new's used space relative to old's. 2829 * Specifically, this is the space that was born before old->ds_creation_txg, 2830 * and freed before new (ie. on new's deadlist or a previous deadlist). 2831 * 2832 * space freed [---------------------] 2833 * snapshots ---O-------O--------O-------O------ 2834 * oldsnap new 2835 */ 2836 int 2837 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 2838 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2839 { 2840 int err = 0; 2841 uint64_t snapobj; 2842 dsl_pool_t *dp = new->ds_dir->dd_pool; 2843 2844 ASSERT(dsl_pool_config_held(dp)); 2845 2846 *usedp = 0; 2847 *usedp += new->ds_phys->ds_referenced_bytes; 2848 *usedp -= oldsnap->ds_phys->ds_referenced_bytes; 2849 2850 *compp = 0; 2851 *compp += new->ds_phys->ds_compressed_bytes; 2852 *compp -= oldsnap->ds_phys->ds_compressed_bytes; 2853 2854 *uncompp = 0; 2855 *uncompp += new->ds_phys->ds_uncompressed_bytes; 2856 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes; 2857 2858 snapobj = new->ds_object; 2859 while (snapobj != oldsnap->ds_object) { 2860 dsl_dataset_t *snap; 2861 uint64_t used, comp, uncomp; 2862 2863 if (snapobj == new->ds_object) { 2864 snap = new; 2865 } else { 2866 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 2867 if (err != 0) 2868 break; 2869 } 2870 2871 if (snap->ds_phys->ds_prev_snap_txg == 2872 oldsnap->ds_phys->ds_creation_txg) { 2873 /* 2874 * The blocks in the deadlist can not be born after 2875 * ds_prev_snap_txg, so get the whole deadlist space, 2876 * which is more efficient (especially for old-format 2877 * deadlists). Unfortunately the deadlist code 2878 * doesn't have enough information to make this 2879 * optimization itself. 2880 */ 2881 dsl_deadlist_space(&snap->ds_deadlist, 2882 &used, &comp, &uncomp); 2883 } else { 2884 dsl_deadlist_space_range(&snap->ds_deadlist, 2885 0, oldsnap->ds_phys->ds_creation_txg, 2886 &used, &comp, &uncomp); 2887 } 2888 *usedp += used; 2889 *compp += comp; 2890 *uncompp += uncomp; 2891 2892 /* 2893 * If we get to the beginning of the chain of snapshots 2894 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 2895 * was not a snapshot of/before new. 2896 */ 2897 snapobj = snap->ds_phys->ds_prev_snap_obj; 2898 if (snap != new) 2899 dsl_dataset_rele(snap, FTAG); 2900 if (snapobj == 0) { 2901 err = SET_ERROR(EINVAL); 2902 break; 2903 } 2904 2905 } 2906 return (err); 2907 } 2908 2909 /* 2910 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 2911 * lastsnap, and all snapshots in between are deleted. 2912 * 2913 * blocks that would be freed [---------------------------] 2914 * snapshots ---O-------O--------O-------O--------O 2915 * firstsnap lastsnap 2916 * 2917 * This is the set of blocks that were born after the snap before firstsnap, 2918 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 2919 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 2920 * We calculate this by iterating over the relevant deadlists (from the snap 2921 * after lastsnap, backward to the snap after firstsnap), summing up the 2922 * space on the deadlist that was born after the snap before firstsnap. 2923 */ 2924 int 2925 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 2926 dsl_dataset_t *lastsnap, 2927 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2928 { 2929 int err = 0; 2930 uint64_t snapobj; 2931 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 2932 2933 ASSERT(dsl_dataset_is_snapshot(firstsnap)); 2934 ASSERT(dsl_dataset_is_snapshot(lastsnap)); 2935 2936 /* 2937 * Check that the snapshots are in the same dsl_dir, and firstsnap 2938 * is before lastsnap. 2939 */ 2940 if (firstsnap->ds_dir != lastsnap->ds_dir || 2941 firstsnap->ds_phys->ds_creation_txg > 2942 lastsnap->ds_phys->ds_creation_txg) 2943 return (SET_ERROR(EINVAL)); 2944 2945 *usedp = *compp = *uncompp = 0; 2946 2947 snapobj = lastsnap->ds_phys->ds_next_snap_obj; 2948 while (snapobj != firstsnap->ds_object) { 2949 dsl_dataset_t *ds; 2950 uint64_t used, comp, uncomp; 2951 2952 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 2953 if (err != 0) 2954 break; 2955 2956 dsl_deadlist_space_range(&ds->ds_deadlist, 2957 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2958 &used, &comp, &uncomp); 2959 *usedp += used; 2960 *compp += comp; 2961 *uncompp += uncomp; 2962 2963 snapobj = ds->ds_phys->ds_prev_snap_obj; 2964 ASSERT3U(snapobj, !=, 0); 2965 dsl_dataset_rele(ds, FTAG); 2966 } 2967 return (err); 2968 } 2969 2970 /* 2971 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 2972 * For example, they could both be snapshots of the same filesystem, and 2973 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 2974 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 2975 * filesystem. Or 'earlier' could be the origin's origin. 2976 * 2977 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg. 2978 */ 2979 boolean_t 2980 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier, 2981 uint64_t earlier_txg) 2982 { 2983 dsl_pool_t *dp = later->ds_dir->dd_pool; 2984 int error; 2985 boolean_t ret; 2986 2987 ASSERT(dsl_pool_config_held(dp)); 2988 ASSERT(dsl_dataset_is_snapshot(earlier) || earlier_txg != 0); 2989 2990 if (earlier_txg == 0) 2991 earlier_txg = earlier->ds_phys->ds_creation_txg; 2992 2993 if (dsl_dataset_is_snapshot(later) && 2994 earlier_txg >= later->ds_phys->ds_creation_txg) 2995 return (B_FALSE); 2996 2997 if (later->ds_dir == earlier->ds_dir) 2998 return (B_TRUE); 2999 if (!dsl_dir_is_clone(later->ds_dir)) 3000 return (B_FALSE); 3001 3002 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object) 3003 return (B_TRUE); 3004 dsl_dataset_t *origin; 3005 error = dsl_dataset_hold_obj(dp, 3006 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin); 3007 if (error != 0) 3008 return (B_FALSE); 3009 ret = dsl_dataset_is_before(origin, earlier, earlier_txg); 3010 dsl_dataset_rele(origin, FTAG); 3011 return (ret); 3012 } 3013 3014 3015 void 3016 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx) 3017 { 3018 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 3019 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx); 3020 } 3021