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 * Copyright (c) 2014 RackTop Systems. 26 */ 27 28 #include <sys/dmu_objset.h> 29 #include <sys/dsl_dataset.h> 30 #include <sys/dsl_dir.h> 31 #include <sys/dsl_prop.h> 32 #include <sys/dsl_synctask.h> 33 #include <sys/dmu_traverse.h> 34 #include <sys/dmu_impl.h> 35 #include <sys/dmu_tx.h> 36 #include <sys/arc.h> 37 #include <sys/zio.h> 38 #include <sys/zap.h> 39 #include <sys/zfeature.h> 40 #include <sys/unique.h> 41 #include <sys/zfs_context.h> 42 #include <sys/zfs_ioctl.h> 43 #include <sys/spa.h> 44 #include <sys/zfs_znode.h> 45 #include <sys/zfs_onexit.h> 46 #include <sys/zvol.h> 47 #include <sys/dsl_scan.h> 48 #include <sys/dsl_deadlist.h> 49 #include <sys/dsl_destroy.h> 50 #include <sys/dsl_userhold.h> 51 #include <sys/dsl_bookmark.h> 52 53 #define SWITCH64(x, y) \ 54 { \ 55 uint64_t __tmp = (x); \ 56 (x) = (y); \ 57 (y) = __tmp; \ 58 } 59 60 #define DS_REF_MAX (1ULL << 62) 61 62 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 63 64 /* 65 * Figure out how much of this delta should be propogated to the dsl_dir 66 * layer. If there's a refreservation, that space has already been 67 * partially accounted for in our ancestors. 68 */ 69 static int64_t 70 parent_delta(dsl_dataset_t *ds, int64_t delta) 71 { 72 uint64_t old_bytes, new_bytes; 73 74 if (ds->ds_reserved == 0) 75 return (delta); 76 77 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 78 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 79 80 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 81 return (new_bytes - old_bytes); 82 } 83 84 void 85 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 86 { 87 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 88 int compressed = BP_GET_PSIZE(bp); 89 int uncompressed = BP_GET_UCSIZE(bp); 90 int64_t delta; 91 92 dprintf_bp(bp, "ds=%p", ds); 93 94 ASSERT(dmu_tx_is_syncing(tx)); 95 /* It could have been compressed away to nothing */ 96 if (BP_IS_HOLE(bp)) 97 return; 98 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 99 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 100 if (ds == NULL) { 101 dsl_pool_mos_diduse_space(tx->tx_pool, 102 used, compressed, uncompressed); 103 return; 104 } 105 106 dmu_buf_will_dirty(ds->ds_dbuf, tx); 107 mutex_enter(&ds->ds_lock); 108 delta = parent_delta(ds, used); 109 ds->ds_phys->ds_referenced_bytes += used; 110 ds->ds_phys->ds_compressed_bytes += compressed; 111 ds->ds_phys->ds_uncompressed_bytes += uncompressed; 112 ds->ds_phys->ds_unique_bytes += used; 113 mutex_exit(&ds->ds_lock); 114 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 115 compressed, uncompressed, tx); 116 dsl_dir_transfer_space(ds->ds_dir, used - delta, 117 DD_USED_REFRSRV, DD_USED_HEAD, tx); 118 } 119 120 int 121 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 122 boolean_t async) 123 { 124 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 125 int compressed = BP_GET_PSIZE(bp); 126 int uncompressed = BP_GET_UCSIZE(bp); 127 128 if (BP_IS_HOLE(bp)) 129 return (0); 130 131 ASSERT(dmu_tx_is_syncing(tx)); 132 ASSERT(bp->blk_birth <= tx->tx_txg); 133 134 if (ds == NULL) { 135 dsl_free(tx->tx_pool, tx->tx_txg, bp); 136 dsl_pool_mos_diduse_space(tx->tx_pool, 137 -used, -compressed, -uncompressed); 138 return (used); 139 } 140 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 141 142 ASSERT(!dsl_dataset_is_snapshot(ds)); 143 dmu_buf_will_dirty(ds->ds_dbuf, tx); 144 145 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) { 146 int64_t delta; 147 148 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 149 dsl_free(tx->tx_pool, tx->tx_txg, bp); 150 151 mutex_enter(&ds->ds_lock); 152 ASSERT(ds->ds_phys->ds_unique_bytes >= used || 153 !DS_UNIQUE_IS_ACCURATE(ds)); 154 delta = parent_delta(ds, -used); 155 ds->ds_phys->ds_unique_bytes -= used; 156 mutex_exit(&ds->ds_lock); 157 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 158 delta, -compressed, -uncompressed, tx); 159 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 160 DD_USED_REFRSRV, DD_USED_HEAD, tx); 161 } else { 162 dprintf_bp(bp, "putting on dead list: %s", ""); 163 if (async) { 164 /* 165 * We are here as part of zio's write done callback, 166 * which means we're a zio interrupt thread. We can't 167 * call dsl_deadlist_insert() now because it may block 168 * waiting for I/O. Instead, put bp on the deferred 169 * queue and let dsl_pool_sync() finish the job. 170 */ 171 bplist_append(&ds->ds_pending_deadlist, bp); 172 } else { 173 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 174 } 175 ASSERT3U(ds->ds_prev->ds_object, ==, 176 ds->ds_phys->ds_prev_snap_obj); 177 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0); 178 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 179 if (ds->ds_prev->ds_phys->ds_next_snap_obj == 180 ds->ds_object && bp->blk_birth > 181 ds->ds_prev->ds_phys->ds_prev_snap_txg) { 182 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 183 mutex_enter(&ds->ds_prev->ds_lock); 184 ds->ds_prev->ds_phys->ds_unique_bytes += used; 185 mutex_exit(&ds->ds_prev->ds_lock); 186 } 187 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 188 dsl_dir_transfer_space(ds->ds_dir, used, 189 DD_USED_HEAD, DD_USED_SNAP, tx); 190 } 191 } 192 mutex_enter(&ds->ds_lock); 193 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used); 194 ds->ds_phys->ds_referenced_bytes -= used; 195 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed); 196 ds->ds_phys->ds_compressed_bytes -= compressed; 197 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed); 198 ds->ds_phys->ds_uncompressed_bytes -= uncompressed; 199 mutex_exit(&ds->ds_lock); 200 201 return (used); 202 } 203 204 uint64_t 205 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 206 { 207 uint64_t trysnap = 0; 208 209 if (ds == NULL) 210 return (0); 211 /* 212 * The snapshot creation could fail, but that would cause an 213 * incorrect FALSE return, which would only result in an 214 * overestimation of the amount of space that an operation would 215 * consume, which is OK. 216 * 217 * There's also a small window where we could miss a pending 218 * snapshot, because we could set the sync task in the quiescing 219 * phase. So this should only be used as a guess. 220 */ 221 if (ds->ds_trysnap_txg > 222 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 223 trysnap = ds->ds_trysnap_txg; 224 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap)); 225 } 226 227 boolean_t 228 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp, 229 uint64_t blk_birth) 230 { 231 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) || 232 (bp != NULL && BP_IS_HOLE(bp))) 233 return (B_FALSE); 234 235 ddt_prefetch(dsl_dataset_get_spa(ds), bp); 236 237 return (B_TRUE); 238 } 239 240 /* ARGSUSED */ 241 static void 242 dsl_dataset_evict(dmu_buf_t *db, void *dsv) 243 { 244 dsl_dataset_t *ds = dsv; 245 246 ASSERT(ds->ds_owner == NULL); 247 248 unique_remove(ds->ds_fsid_guid); 249 250 if (ds->ds_objset != NULL) 251 dmu_objset_evict(ds->ds_objset); 252 253 if (ds->ds_prev) { 254 dsl_dataset_rele(ds->ds_prev, ds); 255 ds->ds_prev = NULL; 256 } 257 258 bplist_destroy(&ds->ds_pending_deadlist); 259 if (ds->ds_phys->ds_deadlist_obj != 0) 260 dsl_deadlist_close(&ds->ds_deadlist); 261 if (ds->ds_dir) 262 dsl_dir_rele(ds->ds_dir, ds); 263 264 ASSERT(!list_link_active(&ds->ds_synced_link)); 265 266 mutex_destroy(&ds->ds_lock); 267 mutex_destroy(&ds->ds_opening_lock); 268 refcount_destroy(&ds->ds_longholds); 269 270 kmem_free(ds, sizeof (dsl_dataset_t)); 271 } 272 273 int 274 dsl_dataset_get_snapname(dsl_dataset_t *ds) 275 { 276 dsl_dataset_phys_t *headphys; 277 int err; 278 dmu_buf_t *headdbuf; 279 dsl_pool_t *dp = ds->ds_dir->dd_pool; 280 objset_t *mos = dp->dp_meta_objset; 281 282 if (ds->ds_snapname[0]) 283 return (0); 284 if (ds->ds_phys->ds_next_snap_obj == 0) 285 return (0); 286 287 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 288 FTAG, &headdbuf); 289 if (err != 0) 290 return (err); 291 headphys = headdbuf->db_data; 292 err = zap_value_search(dp->dp_meta_objset, 293 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 294 dmu_buf_rele(headdbuf, FTAG); 295 return (err); 296 } 297 298 int 299 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 300 { 301 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 302 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 303 matchtype_t mt; 304 int err; 305 306 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 307 mt = MT_FIRST; 308 else 309 mt = MT_EXACT; 310 311 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 312 value, mt, NULL, 0, NULL); 313 if (err == ENOTSUP && mt == MT_FIRST) 314 err = zap_lookup(mos, snapobj, name, 8, 1, value); 315 return (err); 316 } 317 318 int 319 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx) 320 { 321 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 322 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 323 matchtype_t mt; 324 int err; 325 326 dsl_dir_snap_cmtime_update(ds->ds_dir); 327 328 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 329 mt = MT_FIRST; 330 else 331 mt = MT_EXACT; 332 333 err = zap_remove_norm(mos, snapobj, name, mt, tx); 334 if (err == ENOTSUP && mt == MT_FIRST) 335 err = zap_remove(mos, snapobj, name, tx); 336 return (err); 337 } 338 339 int 340 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 341 dsl_dataset_t **dsp) 342 { 343 objset_t *mos = dp->dp_meta_objset; 344 dmu_buf_t *dbuf; 345 dsl_dataset_t *ds; 346 int err; 347 dmu_object_info_t doi; 348 349 ASSERT(dsl_pool_config_held(dp)); 350 351 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 352 if (err != 0) 353 return (err); 354 355 /* Make sure dsobj has the correct object type. */ 356 dmu_object_info_from_db(dbuf, &doi); 357 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) { 358 dmu_buf_rele(dbuf, tag); 359 return (SET_ERROR(EINVAL)); 360 } 361 362 ds = dmu_buf_get_user(dbuf); 363 if (ds == NULL) { 364 dsl_dataset_t *winner = NULL; 365 366 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 367 ds->ds_dbuf = dbuf; 368 ds->ds_object = dsobj; 369 ds->ds_phys = dbuf->db_data; 370 371 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 372 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 373 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 374 refcount_create(&ds->ds_longholds); 375 376 bplist_create(&ds->ds_pending_deadlist); 377 dsl_deadlist_open(&ds->ds_deadlist, 378 mos, ds->ds_phys->ds_deadlist_obj); 379 380 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 381 offsetof(dmu_sendarg_t, dsa_link)); 382 383 if (err == 0) { 384 err = dsl_dir_hold_obj(dp, 385 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 386 } 387 if (err != 0) { 388 mutex_destroy(&ds->ds_lock); 389 mutex_destroy(&ds->ds_opening_lock); 390 refcount_destroy(&ds->ds_longholds); 391 bplist_destroy(&ds->ds_pending_deadlist); 392 dsl_deadlist_close(&ds->ds_deadlist); 393 kmem_free(ds, sizeof (dsl_dataset_t)); 394 dmu_buf_rele(dbuf, tag); 395 return (err); 396 } 397 398 if (!dsl_dataset_is_snapshot(ds)) { 399 ds->ds_snapname[0] = '\0'; 400 if (ds->ds_phys->ds_prev_snap_obj != 0) { 401 err = dsl_dataset_hold_obj(dp, 402 ds->ds_phys->ds_prev_snap_obj, 403 ds, &ds->ds_prev); 404 } 405 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 406 int zaperr = zap_lookup(mos, ds->ds_object, 407 DS_FIELD_BOOKMARK_NAMES, 408 sizeof (ds->ds_bookmarks), 1, 409 &ds->ds_bookmarks); 410 if (zaperr != ENOENT) 411 VERIFY0(zaperr); 412 } 413 } else { 414 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 415 err = dsl_dataset_get_snapname(ds); 416 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) { 417 err = zap_count( 418 ds->ds_dir->dd_pool->dp_meta_objset, 419 ds->ds_phys->ds_userrefs_obj, 420 &ds->ds_userrefs); 421 } 422 } 423 424 if (err == 0 && !dsl_dataset_is_snapshot(ds)) { 425 err = dsl_prop_get_int_ds(ds, 426 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 427 &ds->ds_reserved); 428 if (err == 0) { 429 err = dsl_prop_get_int_ds(ds, 430 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 431 &ds->ds_quota); 432 } 433 } else { 434 ds->ds_reserved = ds->ds_quota = 0; 435 } 436 437 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds, 438 &ds->ds_phys, dsl_dataset_evict)) != NULL) { 439 bplist_destroy(&ds->ds_pending_deadlist); 440 dsl_deadlist_close(&ds->ds_deadlist); 441 if (ds->ds_prev) 442 dsl_dataset_rele(ds->ds_prev, ds); 443 dsl_dir_rele(ds->ds_dir, ds); 444 mutex_destroy(&ds->ds_lock); 445 mutex_destroy(&ds->ds_opening_lock); 446 refcount_destroy(&ds->ds_longholds); 447 kmem_free(ds, sizeof (dsl_dataset_t)); 448 if (err != 0) { 449 dmu_buf_rele(dbuf, tag); 450 return (err); 451 } 452 ds = winner; 453 } else { 454 ds->ds_fsid_guid = 455 unique_insert(ds->ds_phys->ds_fsid_guid); 456 } 457 } 458 ASSERT3P(ds->ds_dbuf, ==, dbuf); 459 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 460 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 || 461 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 462 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 463 *dsp = ds; 464 return (0); 465 } 466 467 int 468 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 469 void *tag, dsl_dataset_t **dsp) 470 { 471 dsl_dir_t *dd; 472 const char *snapname; 473 uint64_t obj; 474 int err = 0; 475 476 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 477 if (err != 0) 478 return (err); 479 480 ASSERT(dsl_pool_config_held(dp)); 481 obj = dd->dd_phys->dd_head_dataset_obj; 482 if (obj != 0) 483 err = dsl_dataset_hold_obj(dp, obj, tag, dsp); 484 else 485 err = SET_ERROR(ENOENT); 486 487 /* we may be looking for a snapshot */ 488 if (err == 0 && snapname != NULL) { 489 dsl_dataset_t *ds; 490 491 if (*snapname++ != '@') { 492 dsl_dataset_rele(*dsp, tag); 493 dsl_dir_rele(dd, FTAG); 494 return (SET_ERROR(ENOENT)); 495 } 496 497 dprintf("looking for snapshot '%s'\n", snapname); 498 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 499 if (err == 0) 500 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 501 dsl_dataset_rele(*dsp, tag); 502 503 if (err == 0) { 504 mutex_enter(&ds->ds_lock); 505 if (ds->ds_snapname[0] == 0) 506 (void) strlcpy(ds->ds_snapname, snapname, 507 sizeof (ds->ds_snapname)); 508 mutex_exit(&ds->ds_lock); 509 *dsp = ds; 510 } 511 } 512 513 dsl_dir_rele(dd, FTAG); 514 return (err); 515 } 516 517 int 518 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 519 void *tag, dsl_dataset_t **dsp) 520 { 521 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 522 if (err != 0) 523 return (err); 524 if (!dsl_dataset_tryown(*dsp, tag)) { 525 dsl_dataset_rele(*dsp, tag); 526 *dsp = NULL; 527 return (SET_ERROR(EBUSY)); 528 } 529 return (0); 530 } 531 532 int 533 dsl_dataset_own(dsl_pool_t *dp, const char *name, 534 void *tag, dsl_dataset_t **dsp) 535 { 536 int err = dsl_dataset_hold(dp, name, tag, dsp); 537 if (err != 0) 538 return (err); 539 if (!dsl_dataset_tryown(*dsp, tag)) { 540 dsl_dataset_rele(*dsp, tag); 541 return (SET_ERROR(EBUSY)); 542 } 543 return (0); 544 } 545 546 /* 547 * See the comment above dsl_pool_hold() for details. In summary, a long 548 * hold is used to prevent destruction of a dataset while the pool hold 549 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 550 * 551 * The dataset and pool must be held when this function is called. After it 552 * is called, the pool hold may be released while the dataset is still held 553 * and accessed. 554 */ 555 void 556 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 557 { 558 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 559 (void) refcount_add(&ds->ds_longholds, tag); 560 } 561 562 void 563 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 564 { 565 (void) refcount_remove(&ds->ds_longholds, tag); 566 } 567 568 /* Return B_TRUE if there are any long holds on this dataset. */ 569 boolean_t 570 dsl_dataset_long_held(dsl_dataset_t *ds) 571 { 572 return (!refcount_is_zero(&ds->ds_longholds)); 573 } 574 575 void 576 dsl_dataset_name(dsl_dataset_t *ds, char *name) 577 { 578 if (ds == NULL) { 579 (void) strcpy(name, "mos"); 580 } else { 581 dsl_dir_name(ds->ds_dir, name); 582 VERIFY0(dsl_dataset_get_snapname(ds)); 583 if (ds->ds_snapname[0]) { 584 (void) strcat(name, "@"); 585 /* 586 * We use a "recursive" mutex so that we 587 * can call dprintf_ds() with ds_lock held. 588 */ 589 if (!MUTEX_HELD(&ds->ds_lock)) { 590 mutex_enter(&ds->ds_lock); 591 (void) strcat(name, ds->ds_snapname); 592 mutex_exit(&ds->ds_lock); 593 } else { 594 (void) strcat(name, ds->ds_snapname); 595 } 596 } 597 } 598 } 599 600 void 601 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 602 { 603 dmu_buf_rele(ds->ds_dbuf, tag); 604 } 605 606 void 607 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 608 { 609 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL); 610 611 mutex_enter(&ds->ds_lock); 612 ds->ds_owner = NULL; 613 mutex_exit(&ds->ds_lock); 614 dsl_dataset_long_rele(ds, tag); 615 if (ds->ds_dbuf != NULL) 616 dsl_dataset_rele(ds, tag); 617 else 618 dsl_dataset_evict(NULL, ds); 619 } 620 621 boolean_t 622 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 623 { 624 boolean_t gotit = FALSE; 625 626 mutex_enter(&ds->ds_lock); 627 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 628 ds->ds_owner = tag; 629 dsl_dataset_long_hold(ds, tag); 630 gotit = TRUE; 631 } 632 mutex_exit(&ds->ds_lock); 633 return (gotit); 634 } 635 636 uint64_t 637 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 638 uint64_t flags, dmu_tx_t *tx) 639 { 640 dsl_pool_t *dp = dd->dd_pool; 641 dmu_buf_t *dbuf; 642 dsl_dataset_phys_t *dsphys; 643 uint64_t dsobj; 644 objset_t *mos = dp->dp_meta_objset; 645 646 if (origin == NULL) 647 origin = dp->dp_origin_snap; 648 649 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 650 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 651 ASSERT(dmu_tx_is_syncing(tx)); 652 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 653 654 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 655 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 656 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 657 dmu_buf_will_dirty(dbuf, tx); 658 dsphys = dbuf->db_data; 659 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 660 dsphys->ds_dir_obj = dd->dd_object; 661 dsphys->ds_flags = flags; 662 dsphys->ds_fsid_guid = unique_create(); 663 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 664 sizeof (dsphys->ds_guid)); 665 dsphys->ds_snapnames_zapobj = 666 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 667 DMU_OT_NONE, 0, tx); 668 dsphys->ds_creation_time = gethrestime_sec(); 669 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 670 671 if (origin == NULL) { 672 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 673 } else { 674 dsl_dataset_t *ohds; /* head of the origin snapshot */ 675 676 dsphys->ds_prev_snap_obj = origin->ds_object; 677 dsphys->ds_prev_snap_txg = 678 origin->ds_phys->ds_creation_txg; 679 dsphys->ds_referenced_bytes = 680 origin->ds_phys->ds_referenced_bytes; 681 dsphys->ds_compressed_bytes = 682 origin->ds_phys->ds_compressed_bytes; 683 dsphys->ds_uncompressed_bytes = 684 origin->ds_phys->ds_uncompressed_bytes; 685 dsphys->ds_bp = origin->ds_phys->ds_bp; 686 dsphys->ds_flags |= origin->ds_phys->ds_flags; 687 688 dmu_buf_will_dirty(origin->ds_dbuf, tx); 689 origin->ds_phys->ds_num_children++; 690 691 VERIFY0(dsl_dataset_hold_obj(dp, 692 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds)); 693 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 694 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 695 dsl_dataset_rele(ohds, FTAG); 696 697 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 698 if (origin->ds_phys->ds_next_clones_obj == 0) { 699 origin->ds_phys->ds_next_clones_obj = 700 zap_create(mos, 701 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 702 } 703 VERIFY0(zap_add_int(mos, 704 origin->ds_phys->ds_next_clones_obj, dsobj, tx)); 705 } 706 707 dmu_buf_will_dirty(dd->dd_dbuf, tx); 708 dd->dd_phys->dd_origin_obj = origin->ds_object; 709 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 710 if (origin->ds_dir->dd_phys->dd_clones == 0) { 711 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 712 origin->ds_dir->dd_phys->dd_clones = 713 zap_create(mos, 714 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 715 } 716 VERIFY0(zap_add_int(mos, 717 origin->ds_dir->dd_phys->dd_clones, dsobj, tx)); 718 } 719 } 720 721 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 722 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 723 724 dmu_buf_rele(dbuf, FTAG); 725 726 dmu_buf_will_dirty(dd->dd_dbuf, tx); 727 dd->dd_phys->dd_head_dataset_obj = dsobj; 728 729 return (dsobj); 730 } 731 732 static void 733 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 734 { 735 objset_t *os; 736 737 VERIFY0(dmu_objset_from_ds(ds, &os)); 738 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 739 dsl_dataset_dirty(ds, tx); 740 } 741 742 uint64_t 743 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 744 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 745 { 746 dsl_pool_t *dp = pdd->dd_pool; 747 uint64_t dsobj, ddobj; 748 dsl_dir_t *dd; 749 750 ASSERT(dmu_tx_is_syncing(tx)); 751 ASSERT(lastname[0] != '@'); 752 753 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 754 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 755 756 dsobj = dsl_dataset_create_sync_dd(dd, origin, 757 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 758 759 dsl_deleg_set_create_perms(dd, tx, cr); 760 761 dsl_dir_rele(dd, FTAG); 762 763 /* 764 * If we are creating a clone, make sure we zero out any stale 765 * data from the origin snapshots zil header. 766 */ 767 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 768 dsl_dataset_t *ds; 769 770 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 771 dsl_dataset_zero_zil(ds, tx); 772 dsl_dataset_rele(ds, FTAG); 773 } 774 775 return (dsobj); 776 } 777 778 /* 779 * The unique space in the head dataset can be calculated by subtracting 780 * the space used in the most recent snapshot, that is still being used 781 * in this file system, from the space currently in use. To figure out 782 * the space in the most recent snapshot still in use, we need to take 783 * the total space used in the snapshot and subtract out the space that 784 * has been freed up since the snapshot was taken. 785 */ 786 void 787 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 788 { 789 uint64_t mrs_used; 790 uint64_t dlused, dlcomp, dluncomp; 791 792 ASSERT(!dsl_dataset_is_snapshot(ds)); 793 794 if (ds->ds_phys->ds_prev_snap_obj != 0) 795 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes; 796 else 797 mrs_used = 0; 798 799 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 800 801 ASSERT3U(dlused, <=, mrs_used); 802 ds->ds_phys->ds_unique_bytes = 803 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused); 804 805 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 806 SPA_VERSION_UNIQUE_ACCURATE) 807 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 808 } 809 810 void 811 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 812 dmu_tx_t *tx) 813 { 814 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 815 uint64_t count; 816 int err; 817 818 ASSERT(ds->ds_phys->ds_num_children >= 2); 819 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx); 820 /* 821 * The err should not be ENOENT, but a bug in a previous version 822 * of the code could cause upgrade_clones_cb() to not set 823 * ds_next_snap_obj when it should, leading to a missing entry. 824 * If we knew that the pool was created after 825 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 826 * ENOENT. However, at least we can check that we don't have 827 * too many entries in the next_clones_obj even after failing to 828 * remove this one. 829 */ 830 if (err != ENOENT) 831 VERIFY0(err); 832 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 833 &count)); 834 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2); 835 } 836 837 838 blkptr_t * 839 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 840 { 841 return (&ds->ds_phys->ds_bp); 842 } 843 844 void 845 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 846 { 847 ASSERT(dmu_tx_is_syncing(tx)); 848 /* If it's the meta-objset, set dp_meta_rootbp */ 849 if (ds == NULL) { 850 tx->tx_pool->dp_meta_rootbp = *bp; 851 } else { 852 dmu_buf_will_dirty(ds->ds_dbuf, tx); 853 ds->ds_phys->ds_bp = *bp; 854 } 855 } 856 857 spa_t * 858 dsl_dataset_get_spa(dsl_dataset_t *ds) 859 { 860 return (ds->ds_dir->dd_pool->dp_spa); 861 } 862 863 void 864 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 865 { 866 dsl_pool_t *dp; 867 868 if (ds == NULL) /* this is the meta-objset */ 869 return; 870 871 ASSERT(ds->ds_objset != NULL); 872 873 if (ds->ds_phys->ds_next_snap_obj != 0) 874 panic("dirtying snapshot!"); 875 876 dp = ds->ds_dir->dd_pool; 877 878 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 879 /* up the hold count until we can be written out */ 880 dmu_buf_add_ref(ds->ds_dbuf, ds); 881 } 882 } 883 884 boolean_t 885 dsl_dataset_is_dirty(dsl_dataset_t *ds) 886 { 887 for (int t = 0; t < TXG_SIZE; t++) { 888 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 889 ds, t)) 890 return (B_TRUE); 891 } 892 return (B_FALSE); 893 } 894 895 static int 896 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 897 { 898 uint64_t asize; 899 900 if (!dmu_tx_is_syncing(tx)) 901 return (0); 902 903 /* 904 * If there's an fs-only reservation, any blocks that might become 905 * owned by the snapshot dataset must be accommodated by space 906 * outside of the reservation. 907 */ 908 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 909 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 910 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 911 return (SET_ERROR(ENOSPC)); 912 913 /* 914 * Propagate any reserved space for this snapshot to other 915 * snapshot checks in this sync group. 916 */ 917 if (asize > 0) 918 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 919 920 return (0); 921 } 922 923 typedef struct dsl_dataset_snapshot_arg { 924 nvlist_t *ddsa_snaps; 925 nvlist_t *ddsa_props; 926 nvlist_t *ddsa_errors; 927 } dsl_dataset_snapshot_arg_t; 928 929 int 930 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 931 dmu_tx_t *tx, boolean_t recv) 932 { 933 int error; 934 uint64_t value; 935 936 ds->ds_trysnap_txg = tx->tx_txg; 937 938 if (!dmu_tx_is_syncing(tx)) 939 return (0); 940 941 /* 942 * We don't allow multiple snapshots of the same txg. If there 943 * is already one, try again. 944 */ 945 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 946 return (SET_ERROR(EAGAIN)); 947 948 /* 949 * Check for conflicting snapshot name. 950 */ 951 error = dsl_dataset_snap_lookup(ds, snapname, &value); 952 if (error == 0) 953 return (SET_ERROR(EEXIST)); 954 if (error != ENOENT) 955 return (error); 956 957 /* 958 * We don't allow taking snapshots of inconsistent datasets, such as 959 * those into which we are currently receiving. However, if we are 960 * creating this snapshot as part of a receive, this check will be 961 * executed atomically with respect to the completion of the receive 962 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 963 * case we ignore this, knowing it will be fixed up for us shortly in 964 * dmu_recv_end_sync(). 965 */ 966 if (!recv && DS_IS_INCONSISTENT(ds)) 967 return (SET_ERROR(EBUSY)); 968 969 error = dsl_dataset_snapshot_reserve_space(ds, tx); 970 if (error != 0) 971 return (error); 972 973 return (0); 974 } 975 976 static int 977 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 978 { 979 dsl_dataset_snapshot_arg_t *ddsa = arg; 980 dsl_pool_t *dp = dmu_tx_pool(tx); 981 nvpair_t *pair; 982 int rv = 0; 983 984 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 985 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 986 int error = 0; 987 dsl_dataset_t *ds; 988 char *name, *atp; 989 char dsname[MAXNAMELEN]; 990 991 name = nvpair_name(pair); 992 if (strlen(name) >= MAXNAMELEN) 993 error = SET_ERROR(ENAMETOOLONG); 994 if (error == 0) { 995 atp = strchr(name, '@'); 996 if (atp == NULL) 997 error = SET_ERROR(EINVAL); 998 if (error == 0) 999 (void) strlcpy(dsname, name, atp - name + 1); 1000 } 1001 if (error == 0) 1002 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1003 if (error == 0) { 1004 error = dsl_dataset_snapshot_check_impl(ds, 1005 atp + 1, tx, B_FALSE); 1006 dsl_dataset_rele(ds, FTAG); 1007 } 1008 1009 if (error != 0) { 1010 if (ddsa->ddsa_errors != NULL) { 1011 fnvlist_add_int32(ddsa->ddsa_errors, 1012 name, error); 1013 } 1014 rv = error; 1015 } 1016 } 1017 return (rv); 1018 } 1019 1020 void 1021 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1022 dmu_tx_t *tx) 1023 { 1024 static zil_header_t zero_zil; 1025 1026 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1027 dmu_buf_t *dbuf; 1028 dsl_dataset_phys_t *dsphys; 1029 uint64_t dsobj, crtxg; 1030 objset_t *mos = dp->dp_meta_objset; 1031 objset_t *os; 1032 1033 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1034 1035 /* 1036 * If we are on an old pool, the zil must not be active, in which 1037 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1038 */ 1039 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1040 dmu_objset_from_ds(ds, &os) != 0 || 1041 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1042 sizeof (zero_zil)) == 0); 1043 1044 1045 /* 1046 * The origin's ds_creation_txg has to be < TXG_INITIAL 1047 */ 1048 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1049 crtxg = 1; 1050 else 1051 crtxg = tx->tx_txg; 1052 1053 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1054 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1055 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1056 dmu_buf_will_dirty(dbuf, tx); 1057 dsphys = dbuf->db_data; 1058 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1059 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1060 dsphys->ds_fsid_guid = unique_create(); 1061 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1062 sizeof (dsphys->ds_guid)); 1063 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1064 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1065 dsphys->ds_next_snap_obj = ds->ds_object; 1066 dsphys->ds_num_children = 1; 1067 dsphys->ds_creation_time = gethrestime_sec(); 1068 dsphys->ds_creation_txg = crtxg; 1069 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1070 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes; 1071 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1072 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1073 dsphys->ds_flags = ds->ds_phys->ds_flags; 1074 dsphys->ds_bp = ds->ds_phys->ds_bp; 1075 dmu_buf_rele(dbuf, FTAG); 1076 1077 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1078 if (ds->ds_prev) { 1079 uint64_t next_clones_obj = 1080 ds->ds_prev->ds_phys->ds_next_clones_obj; 1081 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1082 ds->ds_object || 1083 ds->ds_prev->ds_phys->ds_num_children > 1); 1084 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1085 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1086 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1087 ds->ds_prev->ds_phys->ds_creation_txg); 1088 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1089 } else if (next_clones_obj != 0) { 1090 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1091 dsphys->ds_next_snap_obj, tx); 1092 VERIFY0(zap_add_int(mos, 1093 next_clones_obj, dsobj, tx)); 1094 } 1095 } 1096 1097 /* 1098 * If we have a reference-reservation on this dataset, we will 1099 * need to increase the amount of refreservation being charged 1100 * since our unique space is going to zero. 1101 */ 1102 if (ds->ds_reserved) { 1103 int64_t delta; 1104 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1105 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 1106 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1107 delta, 0, 0, tx); 1108 } 1109 1110 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1111 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist, 1112 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx); 1113 dsl_deadlist_close(&ds->ds_deadlist); 1114 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj); 1115 dsl_deadlist_add_key(&ds->ds_deadlist, 1116 ds->ds_phys->ds_prev_snap_txg, tx); 1117 1118 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1119 ds->ds_phys->ds_prev_snap_obj = dsobj; 1120 ds->ds_phys->ds_prev_snap_txg = crtxg; 1121 ds->ds_phys->ds_unique_bytes = 0; 1122 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1123 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1124 1125 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1126 snapname, 8, 1, &dsobj, tx)); 1127 1128 if (ds->ds_prev) 1129 dsl_dataset_rele(ds->ds_prev, ds); 1130 VERIFY0(dsl_dataset_hold_obj(dp, 1131 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1132 1133 dsl_scan_ds_snapshotted(ds, tx); 1134 1135 dsl_dir_snap_cmtime_update(ds->ds_dir); 1136 1137 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1138 } 1139 1140 static void 1141 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1142 { 1143 dsl_dataset_snapshot_arg_t *ddsa = arg; 1144 dsl_pool_t *dp = dmu_tx_pool(tx); 1145 nvpair_t *pair; 1146 1147 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1148 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1149 dsl_dataset_t *ds; 1150 char *name, *atp; 1151 char dsname[MAXNAMELEN]; 1152 1153 name = nvpair_name(pair); 1154 atp = strchr(name, '@'); 1155 (void) strlcpy(dsname, name, atp - name + 1); 1156 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1157 1158 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1159 if (ddsa->ddsa_props != NULL) { 1160 dsl_props_set_sync_impl(ds->ds_prev, 1161 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1162 } 1163 dsl_dataset_rele(ds, FTAG); 1164 } 1165 } 1166 1167 /* 1168 * The snapshots must all be in the same pool. 1169 * All-or-nothing: if there are any failures, nothing will be modified. 1170 */ 1171 int 1172 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1173 { 1174 dsl_dataset_snapshot_arg_t ddsa; 1175 nvpair_t *pair; 1176 boolean_t needsuspend; 1177 int error; 1178 spa_t *spa; 1179 char *firstname; 1180 nvlist_t *suspended = NULL; 1181 1182 pair = nvlist_next_nvpair(snaps, NULL); 1183 if (pair == NULL) 1184 return (0); 1185 firstname = nvpair_name(pair); 1186 1187 error = spa_open(firstname, &spa, FTAG); 1188 if (error != 0) 1189 return (error); 1190 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1191 spa_close(spa, FTAG); 1192 1193 if (needsuspend) { 1194 suspended = fnvlist_alloc(); 1195 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1196 pair = nvlist_next_nvpair(snaps, pair)) { 1197 char fsname[MAXNAMELEN]; 1198 char *snapname = nvpair_name(pair); 1199 char *atp; 1200 void *cookie; 1201 1202 atp = strchr(snapname, '@'); 1203 if (atp == NULL) { 1204 error = SET_ERROR(EINVAL); 1205 break; 1206 } 1207 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1208 1209 error = zil_suspend(fsname, &cookie); 1210 if (error != 0) 1211 break; 1212 fnvlist_add_uint64(suspended, fsname, 1213 (uintptr_t)cookie); 1214 } 1215 } 1216 1217 ddsa.ddsa_snaps = snaps; 1218 ddsa.ddsa_props = props; 1219 ddsa.ddsa_errors = errors; 1220 1221 if (error == 0) { 1222 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1223 dsl_dataset_snapshot_sync, &ddsa, 1224 fnvlist_num_pairs(snaps) * 3); 1225 } 1226 1227 if (suspended != NULL) { 1228 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1229 pair = nvlist_next_nvpair(suspended, pair)) { 1230 zil_resume((void *)(uintptr_t) 1231 fnvpair_value_uint64(pair)); 1232 } 1233 fnvlist_free(suspended); 1234 } 1235 1236 return (error); 1237 } 1238 1239 typedef struct dsl_dataset_snapshot_tmp_arg { 1240 const char *ddsta_fsname; 1241 const char *ddsta_snapname; 1242 minor_t ddsta_cleanup_minor; 1243 const char *ddsta_htag; 1244 } dsl_dataset_snapshot_tmp_arg_t; 1245 1246 static int 1247 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1248 { 1249 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1250 dsl_pool_t *dp = dmu_tx_pool(tx); 1251 dsl_dataset_t *ds; 1252 int error; 1253 1254 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1255 if (error != 0) 1256 return (error); 1257 1258 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1259 tx, B_FALSE); 1260 if (error != 0) { 1261 dsl_dataset_rele(ds, FTAG); 1262 return (error); 1263 } 1264 1265 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1266 dsl_dataset_rele(ds, FTAG); 1267 return (SET_ERROR(ENOTSUP)); 1268 } 1269 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1270 B_TRUE, tx); 1271 if (error != 0) { 1272 dsl_dataset_rele(ds, FTAG); 1273 return (error); 1274 } 1275 1276 dsl_dataset_rele(ds, FTAG); 1277 return (0); 1278 } 1279 1280 static void 1281 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1282 { 1283 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1284 dsl_pool_t *dp = dmu_tx_pool(tx); 1285 dsl_dataset_t *ds; 1286 1287 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1288 1289 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1290 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1291 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1292 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1293 1294 dsl_dataset_rele(ds, FTAG); 1295 } 1296 1297 int 1298 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1299 minor_t cleanup_minor, const char *htag) 1300 { 1301 dsl_dataset_snapshot_tmp_arg_t ddsta; 1302 int error; 1303 spa_t *spa; 1304 boolean_t needsuspend; 1305 void *cookie; 1306 1307 ddsta.ddsta_fsname = fsname; 1308 ddsta.ddsta_snapname = snapname; 1309 ddsta.ddsta_cleanup_minor = cleanup_minor; 1310 ddsta.ddsta_htag = htag; 1311 1312 error = spa_open(fsname, &spa, FTAG); 1313 if (error != 0) 1314 return (error); 1315 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1316 spa_close(spa, FTAG); 1317 1318 if (needsuspend) { 1319 error = zil_suspend(fsname, &cookie); 1320 if (error != 0) 1321 return (error); 1322 } 1323 1324 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1325 dsl_dataset_snapshot_tmp_sync, &ddsta, 3); 1326 1327 if (needsuspend) 1328 zil_resume(cookie); 1329 return (error); 1330 } 1331 1332 1333 void 1334 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1335 { 1336 ASSERT(dmu_tx_is_syncing(tx)); 1337 ASSERT(ds->ds_objset != NULL); 1338 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1339 1340 /* 1341 * in case we had to change ds_fsid_guid when we opened it, 1342 * sync it out now. 1343 */ 1344 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1345 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1346 1347 dmu_objset_sync(ds->ds_objset, zio, tx); 1348 } 1349 1350 static void 1351 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1352 { 1353 uint64_t count = 0; 1354 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1355 zap_cursor_t zc; 1356 zap_attribute_t za; 1357 nvlist_t *propval = fnvlist_alloc(); 1358 nvlist_t *val = fnvlist_alloc(); 1359 1360 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1361 1362 /* 1363 * There may be missing entries in ds_next_clones_obj 1364 * due to a bug in a previous version of the code. 1365 * Only trust it if it has the right number of entries. 1366 */ 1367 if (ds->ds_phys->ds_next_clones_obj != 0) { 1368 VERIFY0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 1369 &count)); 1370 } 1371 if (count != ds->ds_phys->ds_num_children - 1) 1372 goto fail; 1373 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj); 1374 zap_cursor_retrieve(&zc, &za) == 0; 1375 zap_cursor_advance(&zc)) { 1376 dsl_dataset_t *clone; 1377 char buf[ZFS_MAXNAMELEN]; 1378 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1379 za.za_first_integer, FTAG, &clone)); 1380 dsl_dir_name(clone->ds_dir, buf); 1381 fnvlist_add_boolean(val, buf); 1382 dsl_dataset_rele(clone, FTAG); 1383 } 1384 zap_cursor_fini(&zc); 1385 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1386 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1387 fail: 1388 nvlist_free(val); 1389 nvlist_free(propval); 1390 } 1391 1392 void 1393 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1394 { 1395 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1396 uint64_t refd, avail, uobjs, aobjs, ratio; 1397 1398 ASSERT(dsl_pool_config_held(dp)); 1399 1400 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1401 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1402 ds->ds_phys->ds_compressed_bytes); 1403 1404 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1405 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1406 ds->ds_phys->ds_uncompressed_bytes); 1407 1408 if (dsl_dataset_is_snapshot(ds)) { 1409 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1410 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1411 ds->ds_phys->ds_unique_bytes); 1412 get_clones_stat(ds, nv); 1413 } else { 1414 dsl_dir_stats(ds->ds_dir, nv); 1415 } 1416 1417 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1418 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1419 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1420 1421 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1422 ds->ds_phys->ds_creation_time); 1423 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1424 ds->ds_phys->ds_creation_txg); 1425 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1426 ds->ds_quota); 1427 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1428 ds->ds_reserved); 1429 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1430 ds->ds_phys->ds_guid); 1431 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1432 ds->ds_phys->ds_unique_bytes); 1433 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1434 ds->ds_object); 1435 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1436 ds->ds_userrefs); 1437 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1438 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1439 1440 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1441 uint64_t written, comp, uncomp; 1442 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1443 dsl_dataset_t *prev; 1444 1445 int err = dsl_dataset_hold_obj(dp, 1446 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev); 1447 if (err == 0) { 1448 err = dsl_dataset_space_written(prev, ds, &written, 1449 &comp, &uncomp); 1450 dsl_dataset_rele(prev, FTAG); 1451 if (err == 0) { 1452 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1453 written); 1454 } 1455 } 1456 } 1457 } 1458 1459 void 1460 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1461 { 1462 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1463 ASSERT(dsl_pool_config_held(dp)); 1464 1465 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1466 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1467 stat->dds_guid = ds->ds_phys->ds_guid; 1468 stat->dds_origin[0] = '\0'; 1469 if (dsl_dataset_is_snapshot(ds)) { 1470 stat->dds_is_snapshot = B_TRUE; 1471 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1472 } else { 1473 stat->dds_is_snapshot = B_FALSE; 1474 stat->dds_num_clones = 0; 1475 1476 if (dsl_dir_is_clone(ds->ds_dir)) { 1477 dsl_dataset_t *ods; 1478 1479 VERIFY0(dsl_dataset_hold_obj(dp, 1480 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1481 dsl_dataset_name(ods, stat->dds_origin); 1482 dsl_dataset_rele(ods, FTAG); 1483 } 1484 } 1485 } 1486 1487 uint64_t 1488 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1489 { 1490 return (ds->ds_fsid_guid); 1491 } 1492 1493 void 1494 dsl_dataset_space(dsl_dataset_t *ds, 1495 uint64_t *refdbytesp, uint64_t *availbytesp, 1496 uint64_t *usedobjsp, uint64_t *availobjsp) 1497 { 1498 *refdbytesp = ds->ds_phys->ds_referenced_bytes; 1499 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1500 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1501 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1502 if (ds->ds_quota != 0) { 1503 /* 1504 * Adjust available bytes according to refquota 1505 */ 1506 if (*refdbytesp < ds->ds_quota) 1507 *availbytesp = MIN(*availbytesp, 1508 ds->ds_quota - *refdbytesp); 1509 else 1510 *availbytesp = 0; 1511 } 1512 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1513 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1514 } 1515 1516 boolean_t 1517 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1518 { 1519 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1520 1521 ASSERT(dsl_pool_config_held(dp)); 1522 if (snap == NULL) 1523 return (B_FALSE); 1524 if (ds->ds_phys->ds_bp.blk_birth > 1525 snap->ds_phys->ds_creation_txg) { 1526 objset_t *os, *os_snap; 1527 /* 1528 * It may be that only the ZIL differs, because it was 1529 * reset in the head. Don't count that as being 1530 * modified. 1531 */ 1532 if (dmu_objset_from_ds(ds, &os) != 0) 1533 return (B_TRUE); 1534 if (dmu_objset_from_ds(snap, &os_snap) != 0) 1535 return (B_TRUE); 1536 return (bcmp(&os->os_phys->os_meta_dnode, 1537 &os_snap->os_phys->os_meta_dnode, 1538 sizeof (os->os_phys->os_meta_dnode)) != 0); 1539 } 1540 return (B_FALSE); 1541 } 1542 1543 typedef struct dsl_dataset_rename_snapshot_arg { 1544 const char *ddrsa_fsname; 1545 const char *ddrsa_oldsnapname; 1546 const char *ddrsa_newsnapname; 1547 boolean_t ddrsa_recursive; 1548 dmu_tx_t *ddrsa_tx; 1549 } dsl_dataset_rename_snapshot_arg_t; 1550 1551 /* ARGSUSED */ 1552 static int 1553 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1554 dsl_dataset_t *hds, void *arg) 1555 { 1556 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1557 int error; 1558 uint64_t val; 1559 1560 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1561 if (error != 0) { 1562 /* ignore nonexistent snapshots */ 1563 return (error == ENOENT ? 0 : error); 1564 } 1565 1566 /* new name should not exist */ 1567 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 1568 if (error == 0) 1569 error = SET_ERROR(EEXIST); 1570 else if (error == ENOENT) 1571 error = 0; 1572 1573 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1574 if (dsl_dir_namelen(hds->ds_dir) + 1 + 1575 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN) 1576 error = SET_ERROR(ENAMETOOLONG); 1577 1578 return (error); 1579 } 1580 1581 static int 1582 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 1583 { 1584 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1585 dsl_pool_t *dp = dmu_tx_pool(tx); 1586 dsl_dataset_t *hds; 1587 int error; 1588 1589 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 1590 if (error != 0) 1591 return (error); 1592 1593 if (ddrsa->ddrsa_recursive) { 1594 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1595 dsl_dataset_rename_snapshot_check_impl, ddrsa, 1596 DS_FIND_CHILDREN); 1597 } else { 1598 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 1599 } 1600 dsl_dataset_rele(hds, FTAG); 1601 return (error); 1602 } 1603 1604 static int 1605 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 1606 dsl_dataset_t *hds, void *arg) 1607 { 1608 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1609 dsl_dataset_t *ds; 1610 uint64_t val; 1611 dmu_tx_t *tx = ddrsa->ddrsa_tx; 1612 int error; 1613 1614 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1615 ASSERT(error == 0 || error == ENOENT); 1616 if (error == ENOENT) { 1617 /* ignore nonexistent snapshots */ 1618 return (0); 1619 } 1620 1621 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 1622 1623 /* log before we change the name */ 1624 spa_history_log_internal_ds(ds, "rename", tx, 1625 "-> @%s", ddrsa->ddrsa_newsnapname); 1626 1627 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx)); 1628 mutex_enter(&ds->ds_lock); 1629 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 1630 mutex_exit(&ds->ds_lock); 1631 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj, 1632 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 1633 1634 dsl_dataset_rele(ds, FTAG); 1635 return (0); 1636 } 1637 1638 static void 1639 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 1640 { 1641 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1642 dsl_pool_t *dp = dmu_tx_pool(tx); 1643 dsl_dataset_t *hds; 1644 1645 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 1646 ddrsa->ddrsa_tx = tx; 1647 if (ddrsa->ddrsa_recursive) { 1648 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1649 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 1650 DS_FIND_CHILDREN)); 1651 } else { 1652 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 1653 } 1654 dsl_dataset_rele(hds, FTAG); 1655 } 1656 1657 int 1658 dsl_dataset_rename_snapshot(const char *fsname, 1659 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 1660 { 1661 dsl_dataset_rename_snapshot_arg_t ddrsa; 1662 1663 ddrsa.ddrsa_fsname = fsname; 1664 ddrsa.ddrsa_oldsnapname = oldsnapname; 1665 ddrsa.ddrsa_newsnapname = newsnapname; 1666 ddrsa.ddrsa_recursive = recursive; 1667 1668 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 1669 dsl_dataset_rename_snapshot_sync, &ddrsa, 1)); 1670 } 1671 1672 /* 1673 * If we're doing an ownership handoff, we need to make sure that there is 1674 * only one long hold on the dataset. We're not allowed to change anything here 1675 * so we don't permanently release the long hold or regular hold here. We want 1676 * to do this only when syncing to avoid the dataset unexpectedly going away 1677 * when we release the long hold. 1678 */ 1679 static int 1680 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 1681 { 1682 boolean_t held; 1683 1684 if (!dmu_tx_is_syncing(tx)) 1685 return (0); 1686 1687 if (owner != NULL) { 1688 VERIFY3P(ds->ds_owner, ==, owner); 1689 dsl_dataset_long_rele(ds, owner); 1690 } 1691 1692 held = dsl_dataset_long_held(ds); 1693 1694 if (owner != NULL) 1695 dsl_dataset_long_hold(ds, owner); 1696 1697 if (held) 1698 return (SET_ERROR(EBUSY)); 1699 1700 return (0); 1701 } 1702 1703 typedef struct dsl_dataset_rollback_arg { 1704 const char *ddra_fsname; 1705 void *ddra_owner; 1706 nvlist_t *ddra_result; 1707 } dsl_dataset_rollback_arg_t; 1708 1709 static int 1710 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 1711 { 1712 dsl_dataset_rollback_arg_t *ddra = arg; 1713 dsl_pool_t *dp = dmu_tx_pool(tx); 1714 dsl_dataset_t *ds; 1715 int64_t unused_refres_delta; 1716 int error; 1717 1718 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 1719 if (error != 0) 1720 return (error); 1721 1722 /* must not be a snapshot */ 1723 if (dsl_dataset_is_snapshot(ds)) { 1724 dsl_dataset_rele(ds, FTAG); 1725 return (SET_ERROR(EINVAL)); 1726 } 1727 1728 /* must have a most recent snapshot */ 1729 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) { 1730 dsl_dataset_rele(ds, FTAG); 1731 return (SET_ERROR(EINVAL)); 1732 } 1733 1734 /* must not have any bookmarks after the most recent snapshot */ 1735 nvlist_t *proprequest = fnvlist_alloc(); 1736 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 1737 nvlist_t *bookmarks = fnvlist_alloc(); 1738 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks); 1739 fnvlist_free(proprequest); 1740 if (error != 0) 1741 return (error); 1742 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL); 1743 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) { 1744 nvlist_t *valuenv = 1745 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair), 1746 zfs_prop_to_name(ZFS_PROP_CREATETXG)); 1747 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value"); 1748 if (createtxg > ds->ds_phys->ds_prev_snap_txg) { 1749 fnvlist_free(bookmarks); 1750 dsl_dataset_rele(ds, FTAG); 1751 return (SET_ERROR(EEXIST)); 1752 } 1753 } 1754 fnvlist_free(bookmarks); 1755 1756 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 1757 if (error != 0) { 1758 dsl_dataset_rele(ds, FTAG); 1759 return (error); 1760 } 1761 1762 /* 1763 * Check if the snap we are rolling back to uses more than 1764 * the refquota. 1765 */ 1766 if (ds->ds_quota != 0 && 1767 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) { 1768 dsl_dataset_rele(ds, FTAG); 1769 return (SET_ERROR(EDQUOT)); 1770 } 1771 1772 /* 1773 * When we do the clone swap, we will temporarily use more space 1774 * due to the refreservation (the head will no longer have any 1775 * unique space, so the entire amount of the refreservation will need 1776 * to be free). We will immediately destroy the clone, freeing 1777 * this space, but the freeing happens over many txg's. 1778 */ 1779 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 1780 ds->ds_phys->ds_unique_bytes); 1781 1782 if (unused_refres_delta > 0 && 1783 unused_refres_delta > 1784 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 1785 dsl_dataset_rele(ds, FTAG); 1786 return (SET_ERROR(ENOSPC)); 1787 } 1788 1789 dsl_dataset_rele(ds, FTAG); 1790 return (0); 1791 } 1792 1793 static void 1794 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 1795 { 1796 dsl_dataset_rollback_arg_t *ddra = arg; 1797 dsl_pool_t *dp = dmu_tx_pool(tx); 1798 dsl_dataset_t *ds, *clone; 1799 uint64_t cloneobj; 1800 char namebuf[ZFS_MAXNAMELEN]; 1801 1802 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 1803 1804 dsl_dataset_name(ds->ds_prev, namebuf); 1805 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 1806 1807 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 1808 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 1809 1810 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 1811 1812 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 1813 dsl_dataset_zero_zil(ds, tx); 1814 1815 dsl_destroy_head_sync_impl(clone, tx); 1816 1817 dsl_dataset_rele(clone, FTAG); 1818 dsl_dataset_rele(ds, FTAG); 1819 } 1820 1821 /* 1822 * Rolls back the given filesystem or volume to the most recent snapshot. 1823 * The name of the most recent snapshot will be returned under key "target" 1824 * in the result nvlist. 1825 * 1826 * If owner != NULL: 1827 * - The existing dataset MUST be owned by the specified owner at entry 1828 * - Upon return, dataset will still be held by the same owner, whether we 1829 * succeed or not. 1830 * 1831 * This mode is required any time the existing filesystem is mounted. See 1832 * notes above zfs_suspend_fs() for further details. 1833 */ 1834 int 1835 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result) 1836 { 1837 dsl_dataset_rollback_arg_t ddra; 1838 1839 ddra.ddra_fsname = fsname; 1840 ddra.ddra_owner = owner; 1841 ddra.ddra_result = result; 1842 1843 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 1844 dsl_dataset_rollback_sync, &ddra, 1)); 1845 } 1846 1847 struct promotenode { 1848 list_node_t link; 1849 dsl_dataset_t *ds; 1850 }; 1851 1852 typedef struct dsl_dataset_promote_arg { 1853 const char *ddpa_clonename; 1854 dsl_dataset_t *ddpa_clone; 1855 list_t shared_snaps, origin_snaps, clone_snaps; 1856 dsl_dataset_t *origin_origin; /* origin of the origin */ 1857 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 1858 char *err_ds; 1859 } dsl_dataset_promote_arg_t; 1860 1861 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 1862 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 1863 void *tag); 1864 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 1865 1866 static int 1867 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 1868 { 1869 dsl_dataset_promote_arg_t *ddpa = arg; 1870 dsl_pool_t *dp = dmu_tx_pool(tx); 1871 dsl_dataset_t *hds; 1872 struct promotenode *snap; 1873 dsl_dataset_t *origin_ds; 1874 int err; 1875 uint64_t unused; 1876 1877 err = promote_hold(ddpa, dp, FTAG); 1878 if (err != 0) 1879 return (err); 1880 1881 hds = ddpa->ddpa_clone; 1882 1883 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) { 1884 promote_rele(ddpa, FTAG); 1885 return (SET_ERROR(EXDEV)); 1886 } 1887 1888 /* 1889 * Compute and check the amount of space to transfer. Since this is 1890 * so expensive, don't do the preliminary check. 1891 */ 1892 if (!dmu_tx_is_syncing(tx)) { 1893 promote_rele(ddpa, FTAG); 1894 return (0); 1895 } 1896 1897 snap = list_head(&ddpa->shared_snaps); 1898 origin_ds = snap->ds; 1899 1900 /* compute origin's new unique space */ 1901 snap = list_tail(&ddpa->clone_snaps); 1902 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 1903 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 1904 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, 1905 &ddpa->unique, &unused, &unused); 1906 1907 /* 1908 * Walk the snapshots that we are moving 1909 * 1910 * Compute space to transfer. Consider the incremental changes 1911 * to used by each snapshot: 1912 * (my used) = (prev's used) + (blocks born) - (blocks killed) 1913 * So each snapshot gave birth to: 1914 * (blocks born) = (my used) - (prev's used) + (blocks killed) 1915 * So a sequence would look like: 1916 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 1917 * Which simplifies to: 1918 * uN + kN + kN-1 + ... + k1 + k0 1919 * Note however, if we stop before we reach the ORIGIN we get: 1920 * uN + kN + kN-1 + ... + kM - uM-1 1921 */ 1922 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes; 1923 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes; 1924 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 1925 for (snap = list_head(&ddpa->shared_snaps); snap; 1926 snap = list_next(&ddpa->shared_snaps, snap)) { 1927 uint64_t val, dlused, dlcomp, dluncomp; 1928 dsl_dataset_t *ds = snap->ds; 1929 1930 /* 1931 * If there are long holds, we won't be able to evict 1932 * the objset. 1933 */ 1934 if (dsl_dataset_long_held(ds)) { 1935 err = SET_ERROR(EBUSY); 1936 goto out; 1937 } 1938 1939 /* Check that the snapshot name does not conflict */ 1940 VERIFY0(dsl_dataset_get_snapname(ds)); 1941 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 1942 if (err == 0) { 1943 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 1944 err = SET_ERROR(EEXIST); 1945 goto out; 1946 } 1947 if (err != ENOENT) 1948 goto out; 1949 1950 /* The very first snapshot does not have a deadlist */ 1951 if (ds->ds_phys->ds_prev_snap_obj == 0) 1952 continue; 1953 1954 dsl_deadlist_space(&ds->ds_deadlist, 1955 &dlused, &dlcomp, &dluncomp); 1956 ddpa->used += dlused; 1957 ddpa->comp += dlcomp; 1958 ddpa->uncomp += dluncomp; 1959 } 1960 1961 /* 1962 * If we are a clone of a clone then we never reached ORIGIN, 1963 * so we need to subtract out the clone origin's used space. 1964 */ 1965 if (ddpa->origin_origin) { 1966 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes; 1967 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes; 1968 ddpa->uncomp -= 1969 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes; 1970 } 1971 1972 /* Check that there is enough space here */ 1973 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 1974 ddpa->used); 1975 if (err != 0) 1976 goto out; 1977 1978 /* 1979 * Compute the amounts of space that will be used by snapshots 1980 * after the promotion (for both origin and clone). For each, 1981 * it is the amount of space that will be on all of their 1982 * deadlists (that was not born before their new origin). 1983 */ 1984 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 1985 uint64_t space; 1986 1987 /* 1988 * Note, typically this will not be a clone of a clone, 1989 * so dd_origin_txg will be < TXG_INITIAL, so 1990 * these snaplist_space() -> dsl_deadlist_space_range() 1991 * calls will be fast because they do not have to 1992 * iterate over all bps. 1993 */ 1994 snap = list_head(&ddpa->origin_snaps); 1995 err = snaplist_space(&ddpa->shared_snaps, 1996 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 1997 if (err != 0) 1998 goto out; 1999 2000 err = snaplist_space(&ddpa->clone_snaps, 2001 snap->ds->ds_dir->dd_origin_txg, &space); 2002 if (err != 0) 2003 goto out; 2004 ddpa->cloneusedsnap += space; 2005 } 2006 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2007 err = snaplist_space(&ddpa->origin_snaps, 2008 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap); 2009 if (err != 0) 2010 goto out; 2011 } 2012 2013 out: 2014 promote_rele(ddpa, FTAG); 2015 return (err); 2016 } 2017 2018 static void 2019 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2020 { 2021 dsl_dataset_promote_arg_t *ddpa = arg; 2022 dsl_pool_t *dp = dmu_tx_pool(tx); 2023 dsl_dataset_t *hds; 2024 struct promotenode *snap; 2025 dsl_dataset_t *origin_ds; 2026 dsl_dataset_t *origin_head; 2027 dsl_dir_t *dd; 2028 dsl_dir_t *odd = NULL; 2029 uint64_t oldnext_obj; 2030 int64_t delta; 2031 2032 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2033 hds = ddpa->ddpa_clone; 2034 2035 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE); 2036 2037 snap = list_head(&ddpa->shared_snaps); 2038 origin_ds = snap->ds; 2039 dd = hds->ds_dir; 2040 2041 snap = list_head(&ddpa->origin_snaps); 2042 origin_head = snap->ds; 2043 2044 /* 2045 * We need to explicitly open odd, since origin_ds's dd will be 2046 * changing. 2047 */ 2048 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2049 NULL, FTAG, &odd)); 2050 2051 /* change origin's next snap */ 2052 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2053 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2054 snap = list_tail(&ddpa->clone_snaps); 2055 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2056 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2057 2058 /* change the origin's next clone */ 2059 if (origin_ds->ds_phys->ds_next_clones_obj) { 2060 dsl_dataset_remove_from_next_clones(origin_ds, 2061 snap->ds->ds_object, tx); 2062 VERIFY0(zap_add_int(dp->dp_meta_objset, 2063 origin_ds->ds_phys->ds_next_clones_obj, 2064 oldnext_obj, tx)); 2065 } 2066 2067 /* change origin */ 2068 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2069 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2070 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2071 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2072 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2073 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2074 origin_head->ds_dir->dd_origin_txg = 2075 origin_ds->ds_phys->ds_creation_txg; 2076 2077 /* change dd_clone entries */ 2078 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2079 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2080 odd->dd_phys->dd_clones, hds->ds_object, tx)); 2081 VERIFY0(zap_add_int(dp->dp_meta_objset, 2082 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2083 hds->ds_object, tx)); 2084 2085 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2086 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2087 origin_head->ds_object, tx)); 2088 if (dd->dd_phys->dd_clones == 0) { 2089 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset, 2090 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 2091 } 2092 VERIFY0(zap_add_int(dp->dp_meta_objset, 2093 dd->dd_phys->dd_clones, origin_head->ds_object, tx)); 2094 } 2095 2096 /* move snapshots to this dir */ 2097 for (snap = list_head(&ddpa->shared_snaps); snap; 2098 snap = list_next(&ddpa->shared_snaps, snap)) { 2099 dsl_dataset_t *ds = snap->ds; 2100 2101 /* 2102 * Property callbacks are registered to a particular 2103 * dsl_dir. Since ours is changing, evict the objset 2104 * so that they will be unregistered from the old dsl_dir. 2105 */ 2106 if (ds->ds_objset) { 2107 dmu_objset_evict(ds->ds_objset); 2108 ds->ds_objset = NULL; 2109 } 2110 2111 /* move snap name entry */ 2112 VERIFY0(dsl_dataset_get_snapname(ds)); 2113 VERIFY0(dsl_dataset_snap_remove(origin_head, 2114 ds->ds_snapname, tx)); 2115 VERIFY0(zap_add(dp->dp_meta_objset, 2116 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2117 8, 1, &ds->ds_object, tx)); 2118 2119 /* change containing dsl_dir */ 2120 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2121 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2122 ds->ds_phys->ds_dir_obj = dd->dd_object; 2123 ASSERT3P(ds->ds_dir, ==, odd); 2124 dsl_dir_rele(ds->ds_dir, ds); 2125 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2126 NULL, ds, &ds->ds_dir)); 2127 2128 /* move any clone references */ 2129 if (ds->ds_phys->ds_next_clones_obj && 2130 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2131 zap_cursor_t zc; 2132 zap_attribute_t za; 2133 2134 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2135 ds->ds_phys->ds_next_clones_obj); 2136 zap_cursor_retrieve(&zc, &za) == 0; 2137 zap_cursor_advance(&zc)) { 2138 dsl_dataset_t *cnds; 2139 uint64_t o; 2140 2141 if (za.za_first_integer == oldnext_obj) { 2142 /* 2143 * We've already moved the 2144 * origin's reference. 2145 */ 2146 continue; 2147 } 2148 2149 VERIFY0(dsl_dataset_hold_obj(dp, 2150 za.za_first_integer, FTAG, &cnds)); 2151 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj; 2152 2153 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2154 odd->dd_phys->dd_clones, o, tx)); 2155 VERIFY0(zap_add_int(dp->dp_meta_objset, 2156 dd->dd_phys->dd_clones, o, tx)); 2157 dsl_dataset_rele(cnds, FTAG); 2158 } 2159 zap_cursor_fini(&zc); 2160 } 2161 2162 ASSERT(!dsl_prop_hascb(ds)); 2163 } 2164 2165 /* 2166 * Change space accounting. 2167 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2168 * both be valid, or both be 0 (resulting in delta == 0). This 2169 * is true for each of {clone,origin} independently. 2170 */ 2171 2172 delta = ddpa->cloneusedsnap - 2173 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2174 ASSERT3S(delta, >=, 0); 2175 ASSERT3U(ddpa->used, >=, delta); 2176 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2177 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2178 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2179 2180 delta = ddpa->originusedsnap - 2181 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2182 ASSERT3S(delta, <=, 0); 2183 ASSERT3U(ddpa->used, >=, -delta); 2184 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2185 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2186 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2187 2188 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique; 2189 2190 /* log history record */ 2191 spa_history_log_internal_ds(hds, "promote", tx, ""); 2192 2193 dsl_dir_rele(odd, FTAG); 2194 promote_rele(ddpa, FTAG); 2195 } 2196 2197 /* 2198 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2199 * (exclusive) and last_obj (inclusive). The list will be in reverse 2200 * order (last_obj will be the list_head()). If first_obj == 0, do all 2201 * snapshots back to this dataset's origin. 2202 */ 2203 static int 2204 snaplist_make(dsl_pool_t *dp, 2205 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2206 { 2207 uint64_t obj = last_obj; 2208 2209 list_create(l, sizeof (struct promotenode), 2210 offsetof(struct promotenode, link)); 2211 2212 while (obj != first_obj) { 2213 dsl_dataset_t *ds; 2214 struct promotenode *snap; 2215 int err; 2216 2217 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2218 ASSERT(err != ENOENT); 2219 if (err != 0) 2220 return (err); 2221 2222 if (first_obj == 0) 2223 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2224 2225 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2226 snap->ds = ds; 2227 list_insert_tail(l, snap); 2228 obj = ds->ds_phys->ds_prev_snap_obj; 2229 } 2230 2231 return (0); 2232 } 2233 2234 static int 2235 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2236 { 2237 struct promotenode *snap; 2238 2239 *spacep = 0; 2240 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2241 uint64_t used, comp, uncomp; 2242 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2243 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2244 *spacep += used; 2245 } 2246 return (0); 2247 } 2248 2249 static void 2250 snaplist_destroy(list_t *l, void *tag) 2251 { 2252 struct promotenode *snap; 2253 2254 if (l == NULL || !list_link_active(&l->list_head)) 2255 return; 2256 2257 while ((snap = list_tail(l)) != NULL) { 2258 list_remove(l, snap); 2259 dsl_dataset_rele(snap->ds, tag); 2260 kmem_free(snap, sizeof (*snap)); 2261 } 2262 list_destroy(l); 2263 } 2264 2265 static int 2266 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2267 { 2268 int error; 2269 dsl_dir_t *dd; 2270 struct promotenode *snap; 2271 2272 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2273 &ddpa->ddpa_clone); 2274 if (error != 0) 2275 return (error); 2276 dd = ddpa->ddpa_clone->ds_dir; 2277 2278 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) || 2279 !dsl_dir_is_clone(dd)) { 2280 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2281 return (SET_ERROR(EINVAL)); 2282 } 2283 2284 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj, 2285 &ddpa->shared_snaps, tag); 2286 if (error != 0) 2287 goto out; 2288 2289 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2290 &ddpa->clone_snaps, tag); 2291 if (error != 0) 2292 goto out; 2293 2294 snap = list_head(&ddpa->shared_snaps); 2295 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2296 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj, 2297 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, 2298 &ddpa->origin_snaps, tag); 2299 if (error != 0) 2300 goto out; 2301 2302 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) { 2303 error = dsl_dataset_hold_obj(dp, 2304 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2305 tag, &ddpa->origin_origin); 2306 if (error != 0) 2307 goto out; 2308 } 2309 out: 2310 if (error != 0) 2311 promote_rele(ddpa, tag); 2312 return (error); 2313 } 2314 2315 static void 2316 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2317 { 2318 snaplist_destroy(&ddpa->shared_snaps, tag); 2319 snaplist_destroy(&ddpa->clone_snaps, tag); 2320 snaplist_destroy(&ddpa->origin_snaps, tag); 2321 if (ddpa->origin_origin != NULL) 2322 dsl_dataset_rele(ddpa->origin_origin, tag); 2323 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2324 } 2325 2326 /* 2327 * Promote a clone. 2328 * 2329 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2330 * in with the name. (It must be at least MAXNAMELEN bytes long.) 2331 */ 2332 int 2333 dsl_dataset_promote(const char *name, char *conflsnap) 2334 { 2335 dsl_dataset_promote_arg_t ddpa = { 0 }; 2336 uint64_t numsnaps; 2337 int error; 2338 objset_t *os; 2339 2340 /* 2341 * We will modify space proportional to the number of 2342 * snapshots. Compute numsnaps. 2343 */ 2344 error = dmu_objset_hold(name, FTAG, &os); 2345 if (error != 0) 2346 return (error); 2347 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2348 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps); 2349 dmu_objset_rele(os, FTAG); 2350 if (error != 0) 2351 return (error); 2352 2353 ddpa.ddpa_clonename = name; 2354 ddpa.err_ds = conflsnap; 2355 2356 return (dsl_sync_task(name, dsl_dataset_promote_check, 2357 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps)); 2358 } 2359 2360 int 2361 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2362 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2363 { 2364 int64_t unused_refres_delta; 2365 2366 /* they should both be heads */ 2367 if (dsl_dataset_is_snapshot(clone) || 2368 dsl_dataset_is_snapshot(origin_head)) 2369 return (SET_ERROR(EINVAL)); 2370 2371 /* if we are not forcing, the branch point should be just before them */ 2372 if (!force && clone->ds_prev != origin_head->ds_prev) 2373 return (SET_ERROR(EINVAL)); 2374 2375 /* clone should be the clone (unless they are unrelated) */ 2376 if (clone->ds_prev != NULL && 2377 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2378 origin_head->ds_dir != clone->ds_prev->ds_dir) 2379 return (SET_ERROR(EINVAL)); 2380 2381 /* the clone should be a child of the origin */ 2382 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2383 return (SET_ERROR(EINVAL)); 2384 2385 /* origin_head shouldn't be modified unless 'force' */ 2386 if (!force && 2387 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2388 return (SET_ERROR(ETXTBSY)); 2389 2390 /* origin_head should have no long holds (e.g. is not mounted) */ 2391 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2392 return (SET_ERROR(EBUSY)); 2393 2394 /* check amount of any unconsumed refreservation */ 2395 unused_refres_delta = 2396 (int64_t)MIN(origin_head->ds_reserved, 2397 origin_head->ds_phys->ds_unique_bytes) - 2398 (int64_t)MIN(origin_head->ds_reserved, 2399 clone->ds_phys->ds_unique_bytes); 2400 2401 if (unused_refres_delta > 0 && 2402 unused_refres_delta > 2403 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2404 return (SET_ERROR(ENOSPC)); 2405 2406 /* clone can't be over the head's refquota */ 2407 if (origin_head->ds_quota != 0 && 2408 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota) 2409 return (SET_ERROR(EDQUOT)); 2410 2411 return (0); 2412 } 2413 2414 void 2415 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2416 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2417 { 2418 dsl_pool_t *dp = dmu_tx_pool(tx); 2419 int64_t unused_refres_delta; 2420 2421 ASSERT(clone->ds_reserved == 0); 2422 ASSERT(origin_head->ds_quota == 0 || 2423 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota); 2424 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2425 2426 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2427 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2428 2429 if (clone->ds_objset != NULL) { 2430 dmu_objset_evict(clone->ds_objset); 2431 clone->ds_objset = NULL; 2432 } 2433 2434 if (origin_head->ds_objset != NULL) { 2435 dmu_objset_evict(origin_head->ds_objset); 2436 origin_head->ds_objset = NULL; 2437 } 2438 2439 unused_refres_delta = 2440 (int64_t)MIN(origin_head->ds_reserved, 2441 origin_head->ds_phys->ds_unique_bytes) - 2442 (int64_t)MIN(origin_head->ds_reserved, 2443 clone->ds_phys->ds_unique_bytes); 2444 2445 /* 2446 * Reset origin's unique bytes, if it exists. 2447 */ 2448 if (clone->ds_prev) { 2449 dsl_dataset_t *origin = clone->ds_prev; 2450 uint64_t comp, uncomp; 2451 2452 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2453 dsl_deadlist_space_range(&clone->ds_deadlist, 2454 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2455 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp); 2456 } 2457 2458 /* swap blkptrs */ 2459 { 2460 blkptr_t tmp; 2461 tmp = origin_head->ds_phys->ds_bp; 2462 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp; 2463 clone->ds_phys->ds_bp = tmp; 2464 } 2465 2466 /* set dd_*_bytes */ 2467 { 2468 int64_t dused, dcomp, duncomp; 2469 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2470 uint64_t odl_used, odl_comp, odl_uncomp; 2471 2472 ASSERT3U(clone->ds_dir->dd_phys-> 2473 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2474 2475 dsl_deadlist_space(&clone->ds_deadlist, 2476 &cdl_used, &cdl_comp, &cdl_uncomp); 2477 dsl_deadlist_space(&origin_head->ds_deadlist, 2478 &odl_used, &odl_comp, &odl_uncomp); 2479 2480 dused = clone->ds_phys->ds_referenced_bytes + cdl_used - 2481 (origin_head->ds_phys->ds_referenced_bytes + odl_used); 2482 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp - 2483 (origin_head->ds_phys->ds_compressed_bytes + odl_comp); 2484 duncomp = clone->ds_phys->ds_uncompressed_bytes + 2485 cdl_uncomp - 2486 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2487 2488 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 2489 dused, dcomp, duncomp, tx); 2490 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 2491 -dused, -dcomp, -duncomp, tx); 2492 2493 /* 2494 * The difference in the space used by snapshots is the 2495 * difference in snapshot space due to the head's 2496 * deadlist (since that's the only thing that's 2497 * changing that affects the snapused). 2498 */ 2499 dsl_deadlist_space_range(&clone->ds_deadlist, 2500 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2501 &cdl_used, &cdl_comp, &cdl_uncomp); 2502 dsl_deadlist_space_range(&origin_head->ds_deadlist, 2503 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2504 &odl_used, &odl_comp, &odl_uncomp); 2505 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 2506 DD_USED_HEAD, DD_USED_SNAP, tx); 2507 } 2508 2509 /* swap ds_*_bytes */ 2510 SWITCH64(origin_head->ds_phys->ds_referenced_bytes, 2511 clone->ds_phys->ds_referenced_bytes); 2512 SWITCH64(origin_head->ds_phys->ds_compressed_bytes, 2513 clone->ds_phys->ds_compressed_bytes); 2514 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes, 2515 clone->ds_phys->ds_uncompressed_bytes); 2516 SWITCH64(origin_head->ds_phys->ds_unique_bytes, 2517 clone->ds_phys->ds_unique_bytes); 2518 2519 /* apply any parent delta for change in unconsumed refreservation */ 2520 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 2521 unused_refres_delta, 0, 0, tx); 2522 2523 /* 2524 * Swap deadlists. 2525 */ 2526 dsl_deadlist_close(&clone->ds_deadlist); 2527 dsl_deadlist_close(&origin_head->ds_deadlist); 2528 SWITCH64(origin_head->ds_phys->ds_deadlist_obj, 2529 clone->ds_phys->ds_deadlist_obj); 2530 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 2531 clone->ds_phys->ds_deadlist_obj); 2532 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 2533 origin_head->ds_phys->ds_deadlist_obj); 2534 2535 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 2536 2537 spa_history_log_internal_ds(clone, "clone swap", tx, 2538 "parent=%s", origin_head->ds_dir->dd_myname); 2539 } 2540 2541 /* 2542 * Given a pool name and a dataset object number in that pool, 2543 * return the name of that dataset. 2544 */ 2545 int 2546 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2547 { 2548 dsl_pool_t *dp; 2549 dsl_dataset_t *ds; 2550 int error; 2551 2552 error = dsl_pool_hold(pname, FTAG, &dp); 2553 if (error != 0) 2554 return (error); 2555 2556 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 2557 if (error == 0) { 2558 dsl_dataset_name(ds, buf); 2559 dsl_dataset_rele(ds, FTAG); 2560 } 2561 dsl_pool_rele(dp, FTAG); 2562 2563 return (error); 2564 } 2565 2566 int 2567 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2568 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2569 { 2570 int error = 0; 2571 2572 ASSERT3S(asize, >, 0); 2573 2574 /* 2575 * *ref_rsrv is the portion of asize that will come from any 2576 * unconsumed refreservation space. 2577 */ 2578 *ref_rsrv = 0; 2579 2580 mutex_enter(&ds->ds_lock); 2581 /* 2582 * Make a space adjustment for reserved bytes. 2583 */ 2584 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2585 ASSERT3U(*used, >=, 2586 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2587 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2588 *ref_rsrv = 2589 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2590 } 2591 2592 if (!check_quota || ds->ds_quota == 0) { 2593 mutex_exit(&ds->ds_lock); 2594 return (0); 2595 } 2596 /* 2597 * If they are requesting more space, and our current estimate 2598 * is over quota, they get to try again unless the actual 2599 * on-disk is over quota and there are no pending changes (which 2600 * may free up space for us). 2601 */ 2602 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) { 2603 if (inflight > 0 || 2604 ds->ds_phys->ds_referenced_bytes < ds->ds_quota) 2605 error = SET_ERROR(ERESTART); 2606 else 2607 error = SET_ERROR(EDQUOT); 2608 } 2609 mutex_exit(&ds->ds_lock); 2610 2611 return (error); 2612 } 2613 2614 typedef struct dsl_dataset_set_qr_arg { 2615 const char *ddsqra_name; 2616 zprop_source_t ddsqra_source; 2617 uint64_t ddsqra_value; 2618 } dsl_dataset_set_qr_arg_t; 2619 2620 2621 /* ARGSUSED */ 2622 static int 2623 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 2624 { 2625 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2626 dsl_pool_t *dp = dmu_tx_pool(tx); 2627 dsl_dataset_t *ds; 2628 int error; 2629 uint64_t newval; 2630 2631 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 2632 return (SET_ERROR(ENOTSUP)); 2633 2634 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2635 if (error != 0) 2636 return (error); 2637 2638 if (dsl_dataset_is_snapshot(ds)) { 2639 dsl_dataset_rele(ds, FTAG); 2640 return (SET_ERROR(EINVAL)); 2641 } 2642 2643 error = dsl_prop_predict(ds->ds_dir, 2644 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2645 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2646 if (error != 0) { 2647 dsl_dataset_rele(ds, FTAG); 2648 return (error); 2649 } 2650 2651 if (newval == 0) { 2652 dsl_dataset_rele(ds, FTAG); 2653 return (0); 2654 } 2655 2656 if (newval < ds->ds_phys->ds_referenced_bytes || 2657 newval < ds->ds_reserved) { 2658 dsl_dataset_rele(ds, FTAG); 2659 return (SET_ERROR(ENOSPC)); 2660 } 2661 2662 dsl_dataset_rele(ds, FTAG); 2663 return (0); 2664 } 2665 2666 static void 2667 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 2668 { 2669 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2670 dsl_pool_t *dp = dmu_tx_pool(tx); 2671 dsl_dataset_t *ds; 2672 uint64_t newval; 2673 2674 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2675 2676 dsl_prop_set_sync_impl(ds, 2677 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2678 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 2679 &ddsqra->ddsqra_value, tx); 2680 2681 VERIFY0(dsl_prop_get_int_ds(ds, 2682 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 2683 2684 if (ds->ds_quota != newval) { 2685 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2686 ds->ds_quota = newval; 2687 } 2688 dsl_dataset_rele(ds, FTAG); 2689 } 2690 2691 int 2692 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 2693 uint64_t refquota) 2694 { 2695 dsl_dataset_set_qr_arg_t ddsqra; 2696 2697 ddsqra.ddsqra_name = dsname; 2698 ddsqra.ddsqra_source = source; 2699 ddsqra.ddsqra_value = refquota; 2700 2701 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 2702 dsl_dataset_set_refquota_sync, &ddsqra, 0)); 2703 } 2704 2705 static int 2706 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 2707 { 2708 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2709 dsl_pool_t *dp = dmu_tx_pool(tx); 2710 dsl_dataset_t *ds; 2711 int error; 2712 uint64_t newval, unique; 2713 2714 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 2715 return (SET_ERROR(ENOTSUP)); 2716 2717 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2718 if (error != 0) 2719 return (error); 2720 2721 if (dsl_dataset_is_snapshot(ds)) { 2722 dsl_dataset_rele(ds, FTAG); 2723 return (SET_ERROR(EINVAL)); 2724 } 2725 2726 error = dsl_prop_predict(ds->ds_dir, 2727 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2728 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2729 if (error != 0) { 2730 dsl_dataset_rele(ds, FTAG); 2731 return (error); 2732 } 2733 2734 /* 2735 * If we are doing the preliminary check in open context, the 2736 * space estimates may be inaccurate. 2737 */ 2738 if (!dmu_tx_is_syncing(tx)) { 2739 dsl_dataset_rele(ds, FTAG); 2740 return (0); 2741 } 2742 2743 mutex_enter(&ds->ds_lock); 2744 if (!DS_UNIQUE_IS_ACCURATE(ds)) 2745 dsl_dataset_recalc_head_uniq(ds); 2746 unique = ds->ds_phys->ds_unique_bytes; 2747 mutex_exit(&ds->ds_lock); 2748 2749 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 2750 uint64_t delta = MAX(unique, newval) - 2751 MAX(unique, ds->ds_reserved); 2752 2753 if (delta > 2754 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 2755 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 2756 dsl_dataset_rele(ds, FTAG); 2757 return (SET_ERROR(ENOSPC)); 2758 } 2759 } 2760 2761 dsl_dataset_rele(ds, FTAG); 2762 return (0); 2763 } 2764 2765 void 2766 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 2767 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 2768 { 2769 uint64_t newval; 2770 uint64_t unique; 2771 int64_t delta; 2772 2773 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2774 source, sizeof (value), 1, &value, tx); 2775 2776 VERIFY0(dsl_prop_get_int_ds(ds, 2777 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 2778 2779 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2780 mutex_enter(&ds->ds_dir->dd_lock); 2781 mutex_enter(&ds->ds_lock); 2782 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 2783 unique = ds->ds_phys->ds_unique_bytes; 2784 delta = MAX(0, (int64_t)(newval - unique)) - 2785 MAX(0, (int64_t)(ds->ds_reserved - unique)); 2786 ds->ds_reserved = newval; 2787 mutex_exit(&ds->ds_lock); 2788 2789 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 2790 mutex_exit(&ds->ds_dir->dd_lock); 2791 } 2792 2793 static void 2794 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 2795 { 2796 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2797 dsl_pool_t *dp = dmu_tx_pool(tx); 2798 dsl_dataset_t *ds; 2799 2800 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2801 dsl_dataset_set_refreservation_sync_impl(ds, 2802 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 2803 dsl_dataset_rele(ds, FTAG); 2804 } 2805 2806 int 2807 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 2808 uint64_t refreservation) 2809 { 2810 dsl_dataset_set_qr_arg_t ddsqra; 2811 2812 ddsqra.ddsqra_name = dsname; 2813 ddsqra.ddsqra_source = source; 2814 ddsqra.ddsqra_value = refreservation; 2815 2816 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 2817 dsl_dataset_set_refreservation_sync, &ddsqra, 0)); 2818 } 2819 2820 /* 2821 * Return (in *usedp) the amount of space written in new that is not 2822 * present in oldsnap. New may be a snapshot or the head. Old must be 2823 * a snapshot before new, in new's filesystem (or its origin). If not then 2824 * fail and return EINVAL. 2825 * 2826 * The written space is calculated by considering two components: First, we 2827 * ignore any freed space, and calculate the written as new's used space 2828 * minus old's used space. Next, we add in the amount of space that was freed 2829 * between the two snapshots, thus reducing new's used space relative to old's. 2830 * Specifically, this is the space that was born before old->ds_creation_txg, 2831 * and freed before new (ie. on new's deadlist or a previous deadlist). 2832 * 2833 * space freed [---------------------] 2834 * snapshots ---O-------O--------O-------O------ 2835 * oldsnap new 2836 */ 2837 int 2838 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 2839 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2840 { 2841 int err = 0; 2842 uint64_t snapobj; 2843 dsl_pool_t *dp = new->ds_dir->dd_pool; 2844 2845 ASSERT(dsl_pool_config_held(dp)); 2846 2847 *usedp = 0; 2848 *usedp += new->ds_phys->ds_referenced_bytes; 2849 *usedp -= oldsnap->ds_phys->ds_referenced_bytes; 2850 2851 *compp = 0; 2852 *compp += new->ds_phys->ds_compressed_bytes; 2853 *compp -= oldsnap->ds_phys->ds_compressed_bytes; 2854 2855 *uncompp = 0; 2856 *uncompp += new->ds_phys->ds_uncompressed_bytes; 2857 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes; 2858 2859 snapobj = new->ds_object; 2860 while (snapobj != oldsnap->ds_object) { 2861 dsl_dataset_t *snap; 2862 uint64_t used, comp, uncomp; 2863 2864 if (snapobj == new->ds_object) { 2865 snap = new; 2866 } else { 2867 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 2868 if (err != 0) 2869 break; 2870 } 2871 2872 if (snap->ds_phys->ds_prev_snap_txg == 2873 oldsnap->ds_phys->ds_creation_txg) { 2874 /* 2875 * The blocks in the deadlist can not be born after 2876 * ds_prev_snap_txg, so get the whole deadlist space, 2877 * which is more efficient (especially for old-format 2878 * deadlists). Unfortunately the deadlist code 2879 * doesn't have enough information to make this 2880 * optimization itself. 2881 */ 2882 dsl_deadlist_space(&snap->ds_deadlist, 2883 &used, &comp, &uncomp); 2884 } else { 2885 dsl_deadlist_space_range(&snap->ds_deadlist, 2886 0, oldsnap->ds_phys->ds_creation_txg, 2887 &used, &comp, &uncomp); 2888 } 2889 *usedp += used; 2890 *compp += comp; 2891 *uncompp += uncomp; 2892 2893 /* 2894 * If we get to the beginning of the chain of snapshots 2895 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 2896 * was not a snapshot of/before new. 2897 */ 2898 snapobj = snap->ds_phys->ds_prev_snap_obj; 2899 if (snap != new) 2900 dsl_dataset_rele(snap, FTAG); 2901 if (snapobj == 0) { 2902 err = SET_ERROR(EINVAL); 2903 break; 2904 } 2905 2906 } 2907 return (err); 2908 } 2909 2910 /* 2911 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 2912 * lastsnap, and all snapshots in between are deleted. 2913 * 2914 * blocks that would be freed [---------------------------] 2915 * snapshots ---O-------O--------O-------O--------O 2916 * firstsnap lastsnap 2917 * 2918 * This is the set of blocks that were born after the snap before firstsnap, 2919 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 2920 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 2921 * We calculate this by iterating over the relevant deadlists (from the snap 2922 * after lastsnap, backward to the snap after firstsnap), summing up the 2923 * space on the deadlist that was born after the snap before firstsnap. 2924 */ 2925 int 2926 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 2927 dsl_dataset_t *lastsnap, 2928 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2929 { 2930 int err = 0; 2931 uint64_t snapobj; 2932 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 2933 2934 ASSERT(dsl_dataset_is_snapshot(firstsnap)); 2935 ASSERT(dsl_dataset_is_snapshot(lastsnap)); 2936 2937 /* 2938 * Check that the snapshots are in the same dsl_dir, and firstsnap 2939 * is before lastsnap. 2940 */ 2941 if (firstsnap->ds_dir != lastsnap->ds_dir || 2942 firstsnap->ds_phys->ds_creation_txg > 2943 lastsnap->ds_phys->ds_creation_txg) 2944 return (SET_ERROR(EINVAL)); 2945 2946 *usedp = *compp = *uncompp = 0; 2947 2948 snapobj = lastsnap->ds_phys->ds_next_snap_obj; 2949 while (snapobj != firstsnap->ds_object) { 2950 dsl_dataset_t *ds; 2951 uint64_t used, comp, uncomp; 2952 2953 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 2954 if (err != 0) 2955 break; 2956 2957 dsl_deadlist_space_range(&ds->ds_deadlist, 2958 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2959 &used, &comp, &uncomp); 2960 *usedp += used; 2961 *compp += comp; 2962 *uncompp += uncomp; 2963 2964 snapobj = ds->ds_phys->ds_prev_snap_obj; 2965 ASSERT3U(snapobj, !=, 0); 2966 dsl_dataset_rele(ds, FTAG); 2967 } 2968 return (err); 2969 } 2970 2971 /* 2972 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 2973 * For example, they could both be snapshots of the same filesystem, and 2974 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 2975 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 2976 * filesystem. Or 'earlier' could be the origin's origin. 2977 * 2978 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg. 2979 */ 2980 boolean_t 2981 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier, 2982 uint64_t earlier_txg) 2983 { 2984 dsl_pool_t *dp = later->ds_dir->dd_pool; 2985 int error; 2986 boolean_t ret; 2987 2988 ASSERT(dsl_pool_config_held(dp)); 2989 ASSERT(dsl_dataset_is_snapshot(earlier) || earlier_txg != 0); 2990 2991 if (earlier_txg == 0) 2992 earlier_txg = earlier->ds_phys->ds_creation_txg; 2993 2994 if (dsl_dataset_is_snapshot(later) && 2995 earlier_txg >= later->ds_phys->ds_creation_txg) 2996 return (B_FALSE); 2997 2998 if (later->ds_dir == earlier->ds_dir) 2999 return (B_TRUE); 3000 if (!dsl_dir_is_clone(later->ds_dir)) 3001 return (B_FALSE); 3002 3003 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object) 3004 return (B_TRUE); 3005 dsl_dataset_t *origin; 3006 error = dsl_dataset_hold_obj(dp, 3007 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin); 3008 if (error != 0) 3009 return (B_FALSE); 3010 ret = dsl_dataset_is_before(origin, earlier, earlier_txg); 3011 dsl_dataset_rele(origin, FTAG); 3012 return (ret); 3013 } 3014 3015 3016 void 3017 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx) 3018 { 3019 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 3020 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx); 3021 } 3022