dsl_dataset.c revision 256281
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 * Portions Copyright (c) 2011 Martin Matuska <mm@FreeBSD.org> 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 52#define SWITCH64(x, y) \ 53 { \ 54 uint64_t __tmp = (x); \ 55 (x) = (y); \ 56 (y) = __tmp; \ 57 } 58 59#define DS_REF_MAX (1ULL << 62) 60 61#define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 62 63/* 64 * Figure out how much of this delta should be propogated to the dsl_dir 65 * layer. If there's a refreservation, that space has already been 66 * partially accounted for in our ancestors. 67 */ 68static int64_t 69parent_delta(dsl_dataset_t *ds, int64_t delta) 70{ 71 uint64_t old_bytes, new_bytes; 72 73 if (ds->ds_reserved == 0) 74 return (delta); 75 76 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 77 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 78 79 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 80 return (new_bytes - old_bytes); 81} 82 83void 84dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 85{ 86 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 87 int compressed = BP_GET_PSIZE(bp); 88 int uncompressed = BP_GET_UCSIZE(bp); 89 int64_t delta; 90 91 dprintf_bp(bp, "ds=%p", ds); 92 93 ASSERT(dmu_tx_is_syncing(tx)); 94 /* It could have been compressed away to nothing */ 95 if (BP_IS_HOLE(bp)) 96 return; 97 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 98 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 99 if (ds == NULL) { 100 dsl_pool_mos_diduse_space(tx->tx_pool, 101 used, compressed, uncompressed); 102 return; 103 } 104 105 dmu_buf_will_dirty(ds->ds_dbuf, tx); 106 mutex_enter(&ds->ds_lock); 107 delta = parent_delta(ds, used); 108 ds->ds_phys->ds_referenced_bytes += used; 109 ds->ds_phys->ds_compressed_bytes += compressed; 110 ds->ds_phys->ds_uncompressed_bytes += uncompressed; 111 ds->ds_phys->ds_unique_bytes += used; 112 mutex_exit(&ds->ds_lock); 113 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 114 compressed, uncompressed, tx); 115 dsl_dir_transfer_space(ds->ds_dir, used - delta, 116 DD_USED_REFRSRV, DD_USED_HEAD, tx); 117} 118 119int 120dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 121 boolean_t async) 122{ 123 if (BP_IS_HOLE(bp)) 124 return (0); 125 126 ASSERT(dmu_tx_is_syncing(tx)); 127 ASSERT(bp->blk_birth <= tx->tx_txg); 128 129 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 130 int compressed = BP_GET_PSIZE(bp); 131 int uncompressed = BP_GET_UCSIZE(bp); 132 133 ASSERT(used > 0); 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 204uint64_t 205dsl_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 227boolean_t 228dsl_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 return (B_FALSE); 233 234 ddt_prefetch(dsl_dataset_get_spa(ds), bp); 235 236 return (B_TRUE); 237} 238 239/* ARGSUSED */ 240static void 241dsl_dataset_evict(dmu_buf_t *db, void *dsv) 242{ 243 dsl_dataset_t *ds = dsv; 244 245 ASSERT(ds->ds_owner == NULL); 246 247 unique_remove(ds->ds_fsid_guid); 248 249 if (ds->ds_objset != NULL) 250 dmu_objset_evict(ds->ds_objset); 251 252 if (ds->ds_prev) { 253 dsl_dataset_rele(ds->ds_prev, ds); 254 ds->ds_prev = NULL; 255 } 256 257 bplist_destroy(&ds->ds_pending_deadlist); 258 if (ds->ds_phys->ds_deadlist_obj != 0) 259 dsl_deadlist_close(&ds->ds_deadlist); 260 if (ds->ds_dir) 261 dsl_dir_rele(ds->ds_dir, ds); 262 263 ASSERT(!list_link_active(&ds->ds_synced_link)); 264 265 if (mutex_owned(&ds->ds_lock)) 266 mutex_exit(&ds->ds_lock); 267 mutex_destroy(&ds->ds_lock); 268 if (mutex_owned(&ds->ds_opening_lock)) 269 mutex_exit(&ds->ds_opening_lock); 270 mutex_destroy(&ds->ds_opening_lock); 271 refcount_destroy(&ds->ds_longholds); 272 273 kmem_free(ds, sizeof (dsl_dataset_t)); 274} 275 276int 277dsl_dataset_get_snapname(dsl_dataset_t *ds) 278{ 279 dsl_dataset_phys_t *headphys; 280 int err; 281 dmu_buf_t *headdbuf; 282 dsl_pool_t *dp = ds->ds_dir->dd_pool; 283 objset_t *mos = dp->dp_meta_objset; 284 285 if (ds->ds_snapname[0]) 286 return (0); 287 if (ds->ds_phys->ds_next_snap_obj == 0) 288 return (0); 289 290 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 291 FTAG, &headdbuf); 292 if (err != 0) 293 return (err); 294 headphys = headdbuf->db_data; 295 err = zap_value_search(dp->dp_meta_objset, 296 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 297 dmu_buf_rele(headdbuf, FTAG); 298 return (err); 299} 300 301int 302dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 303{ 304 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 305 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 306 matchtype_t mt; 307 int err; 308 309 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 310 mt = MT_FIRST; 311 else 312 mt = MT_EXACT; 313 314 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 315 value, mt, NULL, 0, NULL); 316 if (err == ENOTSUP && mt == MT_FIRST) 317 err = zap_lookup(mos, snapobj, name, 8, 1, value); 318 return (err); 319} 320 321int 322dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx) 323{ 324 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 325 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 326 matchtype_t mt; 327 int err; 328 329 dsl_dir_snap_cmtime_update(ds->ds_dir); 330 331 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 332 mt = MT_FIRST; 333 else 334 mt = MT_EXACT; 335 336 err = zap_remove_norm(mos, snapobj, name, mt, tx); 337 if (err == ENOTSUP && mt == MT_FIRST) 338 err = zap_remove(mos, snapobj, name, tx); 339 return (err); 340} 341 342int 343dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 344 dsl_dataset_t **dsp) 345{ 346 objset_t *mos = dp->dp_meta_objset; 347 dmu_buf_t *dbuf; 348 dsl_dataset_t *ds; 349 int err; 350 dmu_object_info_t doi; 351 352 ASSERT(dsl_pool_config_held(dp)); 353 354 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 355 if (err != 0) 356 return (err); 357 358 /* Make sure dsobj has the correct object type. */ 359 dmu_object_info_from_db(dbuf, &doi); 360 if (doi.doi_type != DMU_OT_DSL_DATASET) { 361 dmu_buf_rele(dbuf, tag); 362 return (SET_ERROR(EINVAL)); 363 } 364 365 ds = dmu_buf_get_user(dbuf); 366 if (ds == NULL) { 367 dsl_dataset_t *winner = NULL; 368 369 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 370 ds->ds_dbuf = dbuf; 371 ds->ds_object = dsobj; 372 ds->ds_phys = dbuf->db_data; 373 374 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 375 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 376 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 377 refcount_create(&ds->ds_longholds); 378 379 bplist_create(&ds->ds_pending_deadlist); 380 dsl_deadlist_open(&ds->ds_deadlist, 381 mos, ds->ds_phys->ds_deadlist_obj); 382 383 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 384 offsetof(dmu_sendarg_t, dsa_link)); 385 386 if (err == 0) { 387 err = dsl_dir_hold_obj(dp, 388 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 389 } 390 if (err != 0) { 391 mutex_destroy(&ds->ds_lock); 392 mutex_destroy(&ds->ds_opening_lock); 393 refcount_destroy(&ds->ds_longholds); 394 bplist_destroy(&ds->ds_pending_deadlist); 395 dsl_deadlist_close(&ds->ds_deadlist); 396 kmem_free(ds, sizeof (dsl_dataset_t)); 397 dmu_buf_rele(dbuf, tag); 398 return (err); 399 } 400 401 if (!dsl_dataset_is_snapshot(ds)) { 402 ds->ds_snapname[0] = '\0'; 403 if (ds->ds_phys->ds_prev_snap_obj != 0) { 404 err = dsl_dataset_hold_obj(dp, 405 ds->ds_phys->ds_prev_snap_obj, 406 ds, &ds->ds_prev); 407 } 408 } else { 409 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 410 err = dsl_dataset_get_snapname(ds); 411 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) { 412 err = zap_count( 413 ds->ds_dir->dd_pool->dp_meta_objset, 414 ds->ds_phys->ds_userrefs_obj, 415 &ds->ds_userrefs); 416 } 417 } 418 419 if (err == 0 && !dsl_dataset_is_snapshot(ds)) { 420 err = dsl_prop_get_int_ds(ds, 421 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 422 &ds->ds_reserved); 423 if (err == 0) { 424 err = dsl_prop_get_int_ds(ds, 425 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 426 &ds->ds_quota); 427 } 428 } else { 429 ds->ds_reserved = ds->ds_quota = 0; 430 } 431 432 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds, 433 &ds->ds_phys, dsl_dataset_evict)) != NULL) { 434 bplist_destroy(&ds->ds_pending_deadlist); 435 dsl_deadlist_close(&ds->ds_deadlist); 436 if (ds->ds_prev) 437 dsl_dataset_rele(ds->ds_prev, ds); 438 dsl_dir_rele(ds->ds_dir, ds); 439 mutex_destroy(&ds->ds_lock); 440 mutex_destroy(&ds->ds_opening_lock); 441 refcount_destroy(&ds->ds_longholds); 442 kmem_free(ds, sizeof (dsl_dataset_t)); 443 if (err != 0) { 444 dmu_buf_rele(dbuf, tag); 445 return (err); 446 } 447 ds = winner; 448 } else { 449 ds->ds_fsid_guid = 450 unique_insert(ds->ds_phys->ds_fsid_guid); 451 } 452 } 453 ASSERT3P(ds->ds_dbuf, ==, dbuf); 454 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 455 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 || 456 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 457 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 458 *dsp = ds; 459 return (0); 460} 461 462int 463dsl_dataset_hold(dsl_pool_t *dp, const char *name, 464 void *tag, dsl_dataset_t **dsp) 465{ 466 dsl_dir_t *dd; 467 const char *snapname; 468 uint64_t obj; 469 int err = 0; 470 471 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 472 if (err != 0) 473 return (err); 474 475 ASSERT(dsl_pool_config_held(dp)); 476 obj = dd->dd_phys->dd_head_dataset_obj; 477 if (obj != 0) 478 err = dsl_dataset_hold_obj(dp, obj, tag, dsp); 479 else 480 err = SET_ERROR(ENOENT); 481 482 /* we may be looking for a snapshot */ 483 if (err == 0 && snapname != NULL) { 484 dsl_dataset_t *ds; 485 486 if (*snapname++ != '@') { 487 dsl_dataset_rele(*dsp, tag); 488 dsl_dir_rele(dd, FTAG); 489 return (SET_ERROR(ENOENT)); 490 } 491 492 dprintf("looking for snapshot '%s'\n", snapname); 493 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 494 if (err == 0) 495 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 496 dsl_dataset_rele(*dsp, tag); 497 498 if (err == 0) { 499 mutex_enter(&ds->ds_lock); 500 if (ds->ds_snapname[0] == 0) 501 (void) strlcpy(ds->ds_snapname, snapname, 502 sizeof (ds->ds_snapname)); 503 mutex_exit(&ds->ds_lock); 504 *dsp = ds; 505 } 506 } 507 508 dsl_dir_rele(dd, FTAG); 509 return (err); 510} 511 512int 513dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 514 void *tag, dsl_dataset_t **dsp) 515{ 516 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 517 if (err != 0) 518 return (err); 519 if (!dsl_dataset_tryown(*dsp, tag)) { 520 dsl_dataset_rele(*dsp, tag); 521 *dsp = NULL; 522 return (SET_ERROR(EBUSY)); 523 } 524 return (0); 525} 526 527int 528dsl_dataset_own(dsl_pool_t *dp, const char *name, 529 void *tag, dsl_dataset_t **dsp) 530{ 531 int err = dsl_dataset_hold(dp, name, tag, dsp); 532 if (err != 0) 533 return (err); 534 if (!dsl_dataset_tryown(*dsp, tag)) { 535 dsl_dataset_rele(*dsp, tag); 536 return (SET_ERROR(EBUSY)); 537 } 538 return (0); 539} 540 541/* 542 * See the comment above dsl_pool_hold() for details. In summary, a long 543 * hold is used to prevent destruction of a dataset while the pool hold 544 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 545 * 546 * The dataset and pool must be held when this function is called. After it 547 * is called, the pool hold may be released while the dataset is still held 548 * and accessed. 549 */ 550void 551dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 552{ 553 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 554 (void) refcount_add(&ds->ds_longholds, tag); 555} 556 557void 558dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 559{ 560 (void) refcount_remove(&ds->ds_longholds, tag); 561} 562 563/* Return B_TRUE if there are any long holds on this dataset. */ 564boolean_t 565dsl_dataset_long_held(dsl_dataset_t *ds) 566{ 567 return (!refcount_is_zero(&ds->ds_longholds)); 568} 569 570void 571dsl_dataset_name(dsl_dataset_t *ds, char *name) 572{ 573 if (ds == NULL) { 574 (void) strcpy(name, "mos"); 575 } else { 576 dsl_dir_name(ds->ds_dir, name); 577 VERIFY0(dsl_dataset_get_snapname(ds)); 578 if (ds->ds_snapname[0]) { 579 (void) strcat(name, "@"); 580 /* 581 * We use a "recursive" mutex so that we 582 * can call dprintf_ds() with ds_lock held. 583 */ 584 if (!MUTEX_HELD(&ds->ds_lock)) { 585 mutex_enter(&ds->ds_lock); 586 (void) strcat(name, ds->ds_snapname); 587 mutex_exit(&ds->ds_lock); 588 } else { 589 (void) strcat(name, ds->ds_snapname); 590 } 591 } 592 } 593} 594 595void 596dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 597{ 598 dmu_buf_rele(ds->ds_dbuf, tag); 599} 600 601void 602dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 603{ 604 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL); 605 606 mutex_enter(&ds->ds_lock); 607 ds->ds_owner = NULL; 608 mutex_exit(&ds->ds_lock); 609 dsl_dataset_long_rele(ds, tag); 610 if (ds->ds_dbuf != NULL) 611 dsl_dataset_rele(ds, tag); 612 else 613 dsl_dataset_evict(NULL, ds); 614} 615 616boolean_t 617dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 618{ 619 boolean_t gotit = FALSE; 620 621 mutex_enter(&ds->ds_lock); 622 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 623 ds->ds_owner = tag; 624 dsl_dataset_long_hold(ds, tag); 625 gotit = TRUE; 626 } 627 mutex_exit(&ds->ds_lock); 628 return (gotit); 629} 630 631uint64_t 632dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 633 uint64_t flags, dmu_tx_t *tx) 634{ 635 dsl_pool_t *dp = dd->dd_pool; 636 dmu_buf_t *dbuf; 637 dsl_dataset_phys_t *dsphys; 638 uint64_t dsobj; 639 objset_t *mos = dp->dp_meta_objset; 640 641 if (origin == NULL) 642 origin = dp->dp_origin_snap; 643 644 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 645 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 646 ASSERT(dmu_tx_is_syncing(tx)); 647 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 648 649 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 650 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 651 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 652 dmu_buf_will_dirty(dbuf, tx); 653 dsphys = dbuf->db_data; 654 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 655 dsphys->ds_dir_obj = dd->dd_object; 656 dsphys->ds_flags = flags; 657 dsphys->ds_fsid_guid = unique_create(); 658 do { 659 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 660 sizeof (dsphys->ds_guid)); 661 } while (dsphys->ds_guid == 0); 662 dsphys->ds_snapnames_zapobj = 663 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 664 DMU_OT_NONE, 0, tx); 665 dsphys->ds_creation_time = gethrestime_sec(); 666 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 667 668 if (origin == NULL) { 669 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 670 } else { 671 dsl_dataset_t *ohds; /* head of the origin snapshot */ 672 673 dsphys->ds_prev_snap_obj = origin->ds_object; 674 dsphys->ds_prev_snap_txg = 675 origin->ds_phys->ds_creation_txg; 676 dsphys->ds_referenced_bytes = 677 origin->ds_phys->ds_referenced_bytes; 678 dsphys->ds_compressed_bytes = 679 origin->ds_phys->ds_compressed_bytes; 680 dsphys->ds_uncompressed_bytes = 681 origin->ds_phys->ds_uncompressed_bytes; 682 dsphys->ds_bp = origin->ds_phys->ds_bp; 683 dsphys->ds_flags |= origin->ds_phys->ds_flags; 684 685 dmu_buf_will_dirty(origin->ds_dbuf, tx); 686 origin->ds_phys->ds_num_children++; 687 688 VERIFY0(dsl_dataset_hold_obj(dp, 689 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds)); 690 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 691 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 692 dsl_dataset_rele(ohds, FTAG); 693 694 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 695 if (origin->ds_phys->ds_next_clones_obj == 0) { 696 origin->ds_phys->ds_next_clones_obj = 697 zap_create(mos, 698 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 699 } 700 VERIFY0(zap_add_int(mos, 701 origin->ds_phys->ds_next_clones_obj, dsobj, tx)); 702 } 703 704 dmu_buf_will_dirty(dd->dd_dbuf, tx); 705 dd->dd_phys->dd_origin_obj = origin->ds_object; 706 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 707 if (origin->ds_dir->dd_phys->dd_clones == 0) { 708 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 709 origin->ds_dir->dd_phys->dd_clones = 710 zap_create(mos, 711 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 712 } 713 VERIFY0(zap_add_int(mos, 714 origin->ds_dir->dd_phys->dd_clones, dsobj, tx)); 715 } 716 } 717 718 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 719 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 720 721 dmu_buf_rele(dbuf, FTAG); 722 723 dmu_buf_will_dirty(dd->dd_dbuf, tx); 724 dd->dd_phys->dd_head_dataset_obj = dsobj; 725 726 return (dsobj); 727} 728 729static void 730dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 731{ 732 objset_t *os; 733 734 VERIFY0(dmu_objset_from_ds(ds, &os)); 735 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 736 dsl_dataset_dirty(ds, tx); 737} 738 739uint64_t 740dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 741 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 742{ 743 dsl_pool_t *dp = pdd->dd_pool; 744 uint64_t dsobj, ddobj; 745 dsl_dir_t *dd; 746 747 ASSERT(dmu_tx_is_syncing(tx)); 748 ASSERT(lastname[0] != '@'); 749 750 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 751 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 752 753 dsobj = dsl_dataset_create_sync_dd(dd, origin, 754 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 755 756 dsl_deleg_set_create_perms(dd, tx, cr); 757 758 dsl_dir_rele(dd, FTAG); 759 760 /* 761 * If we are creating a clone, make sure we zero out any stale 762 * data from the origin snapshots zil header. 763 */ 764 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 765 dsl_dataset_t *ds; 766 767 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 768 dsl_dataset_zero_zil(ds, tx); 769 dsl_dataset_rele(ds, FTAG); 770 } 771 772 return (dsobj); 773} 774 775#ifdef __FreeBSD__ 776/* FreeBSD ioctl compat begin */ 777struct destroyarg { 778 nvlist_t *nvl; 779 const char *snapname; 780}; 781 782static int 783dsl_check_snap_cb(const char *name, void *arg) 784{ 785 struct destroyarg *da = arg; 786 dsl_dataset_t *ds; 787 char *dsname; 788 789 dsname = kmem_asprintf("%s@%s", name, da->snapname); 790 fnvlist_add_boolean(da->nvl, dsname); 791 kmem_free(dsname, strlen(dsname) + 1); 792 793 return (0); 794} 795 796int 797dmu_get_recursive_snaps_nvl(char *fsname, const char *snapname, 798 nvlist_t *snaps) 799{ 800 struct destroyarg *da; 801 int err; 802 803 da = kmem_zalloc(sizeof (struct destroyarg), KM_SLEEP); 804 da->nvl = snaps; 805 da->snapname = snapname; 806 err = dmu_objset_find(fsname, dsl_check_snap_cb, da, 807 DS_FIND_CHILDREN); 808 kmem_free(da, sizeof (struct destroyarg)); 809 810 return (err); 811} 812/* FreeBSD ioctl compat end */ 813#endif /* __FreeBSD__ */ 814 815/* 816 * The unique space in the head dataset can be calculated by subtracting 817 * the space used in the most recent snapshot, that is still being used 818 * in this file system, from the space currently in use. To figure out 819 * the space in the most recent snapshot still in use, we need to take 820 * the total space used in the snapshot and subtract out the space that 821 * has been freed up since the snapshot was taken. 822 */ 823void 824dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 825{ 826 uint64_t mrs_used; 827 uint64_t dlused, dlcomp, dluncomp; 828 829 ASSERT(!dsl_dataset_is_snapshot(ds)); 830 831 if (ds->ds_phys->ds_prev_snap_obj != 0) 832 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes; 833 else 834 mrs_used = 0; 835 836 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 837 838 ASSERT3U(dlused, <=, mrs_used); 839 ds->ds_phys->ds_unique_bytes = 840 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused); 841 842 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 843 SPA_VERSION_UNIQUE_ACCURATE) 844 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 845} 846 847void 848dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 849 dmu_tx_t *tx) 850{ 851 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 852 uint64_t count; 853 int err; 854 855 ASSERT(ds->ds_phys->ds_num_children >= 2); 856 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx); 857 /* 858 * The err should not be ENOENT, but a bug in a previous version 859 * of the code could cause upgrade_clones_cb() to not set 860 * ds_next_snap_obj when it should, leading to a missing entry. 861 * If we knew that the pool was created after 862 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 863 * ENOENT. However, at least we can check that we don't have 864 * too many entries in the next_clones_obj even after failing to 865 * remove this one. 866 */ 867 if (err != ENOENT) 868 VERIFY0(err); 869 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 870 &count)); 871 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2); 872} 873 874 875blkptr_t * 876dsl_dataset_get_blkptr(dsl_dataset_t *ds) 877{ 878 return (&ds->ds_phys->ds_bp); 879} 880 881void 882dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 883{ 884 ASSERT(dmu_tx_is_syncing(tx)); 885 /* If it's the meta-objset, set dp_meta_rootbp */ 886 if (ds == NULL) { 887 tx->tx_pool->dp_meta_rootbp = *bp; 888 } else { 889 dmu_buf_will_dirty(ds->ds_dbuf, tx); 890 ds->ds_phys->ds_bp = *bp; 891 } 892} 893 894spa_t * 895dsl_dataset_get_spa(dsl_dataset_t *ds) 896{ 897 return (ds->ds_dir->dd_pool->dp_spa); 898} 899 900void 901dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 902{ 903 dsl_pool_t *dp; 904 905 if (ds == NULL) /* this is the meta-objset */ 906 return; 907 908 ASSERT(ds->ds_objset != NULL); 909 910 if (ds->ds_phys->ds_next_snap_obj != 0) 911 panic("dirtying snapshot!"); 912 913 dp = ds->ds_dir->dd_pool; 914 915 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 916 /* up the hold count until we can be written out */ 917 dmu_buf_add_ref(ds->ds_dbuf, ds); 918 } 919} 920 921boolean_t 922dsl_dataset_is_dirty(dsl_dataset_t *ds) 923{ 924 for (int t = 0; t < TXG_SIZE; t++) { 925 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 926 ds, t)) 927 return (B_TRUE); 928 } 929 return (B_FALSE); 930} 931 932static int 933dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 934{ 935 uint64_t asize; 936 937 if (!dmu_tx_is_syncing(tx)) 938 return (0); 939 940 /* 941 * If there's an fs-only reservation, any blocks that might become 942 * owned by the snapshot dataset must be accommodated by space 943 * outside of the reservation. 944 */ 945 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 946 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 947 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 948 return (SET_ERROR(ENOSPC)); 949 950 /* 951 * Propagate any reserved space for this snapshot to other 952 * snapshot checks in this sync group. 953 */ 954 if (asize > 0) 955 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 956 957 return (0); 958} 959 960typedef struct dsl_dataset_snapshot_arg { 961 nvlist_t *ddsa_snaps; 962 nvlist_t *ddsa_props; 963 nvlist_t *ddsa_errors; 964} dsl_dataset_snapshot_arg_t; 965 966int 967dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 968 dmu_tx_t *tx, boolean_t recv) 969{ 970 int error; 971 uint64_t value; 972 973 ds->ds_trysnap_txg = tx->tx_txg; 974 975 if (!dmu_tx_is_syncing(tx)) 976 return (0); 977 978 /* 979 * We don't allow multiple snapshots of the same txg. If there 980 * is already one, try again. 981 */ 982 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 983 return (SET_ERROR(EAGAIN)); 984 985 /* 986 * Check for conflicting snapshot name. 987 */ 988 error = dsl_dataset_snap_lookup(ds, snapname, &value); 989 if (error == 0) 990 return (SET_ERROR(EEXIST)); 991 if (error != ENOENT) 992 return (error); 993 994 /* 995 * We don't allow taking snapshots of inconsistent datasets, such as 996 * those into which we are currently receiving. However, if we are 997 * creating this snapshot as part of a receive, this check will be 998 * executed atomically with respect to the completion of the receive 999 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 1000 * case we ignore this, knowing it will be fixed up for us shortly in 1001 * dmu_recv_end_sync(). 1002 */ 1003 if (!recv && DS_IS_INCONSISTENT(ds)) 1004 return (SET_ERROR(EBUSY)); 1005 1006 error = dsl_dataset_snapshot_reserve_space(ds, tx); 1007 if (error != 0) 1008 return (error); 1009 1010 return (0); 1011} 1012 1013static int 1014dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 1015{ 1016 dsl_dataset_snapshot_arg_t *ddsa = arg; 1017 dsl_pool_t *dp = dmu_tx_pool(tx); 1018 nvpair_t *pair; 1019 int rv = 0; 1020 1021 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1022 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1023 int error = 0; 1024 dsl_dataset_t *ds; 1025 char *name, *atp; 1026 char dsname[MAXNAMELEN]; 1027 1028 name = nvpair_name(pair); 1029 if (strlen(name) >= MAXNAMELEN) 1030 error = SET_ERROR(ENAMETOOLONG); 1031 if (error == 0) { 1032 atp = strchr(name, '@'); 1033 if (atp == NULL) 1034 error = SET_ERROR(EINVAL); 1035 if (error == 0) 1036 (void) strlcpy(dsname, name, atp - name + 1); 1037 } 1038 if (error == 0) 1039 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1040 if (error == 0) { 1041 error = dsl_dataset_snapshot_check_impl(ds, 1042 atp + 1, tx, B_FALSE); 1043 dsl_dataset_rele(ds, FTAG); 1044 } 1045 1046 if (error != 0) { 1047 if (ddsa->ddsa_errors != NULL) { 1048 fnvlist_add_int32(ddsa->ddsa_errors, 1049 name, error); 1050 } 1051 rv = error; 1052 } 1053 } 1054 return (rv); 1055} 1056 1057void 1058dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1059 dmu_tx_t *tx) 1060{ 1061 static zil_header_t zero_zil; 1062 1063 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1064 dmu_buf_t *dbuf; 1065 dsl_dataset_phys_t *dsphys; 1066 uint64_t dsobj, crtxg; 1067 objset_t *mos = dp->dp_meta_objset; 1068 objset_t *os; 1069 1070 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1071 1072 /* 1073 * If we are on an old pool, the zil must not be active, in which 1074 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1075 */ 1076 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1077 dmu_objset_from_ds(ds, &os) != 0 || 1078 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1079 sizeof (zero_zil)) == 0); 1080 1081 1082 /* 1083 * The origin's ds_creation_txg has to be < TXG_INITIAL 1084 */ 1085 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1086 crtxg = 1; 1087 else 1088 crtxg = tx->tx_txg; 1089 1090 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1091 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1092 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1093 dmu_buf_will_dirty(dbuf, tx); 1094 dsphys = dbuf->db_data; 1095 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1096 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1097 dsphys->ds_fsid_guid = unique_create(); 1098 do { 1099 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1100 sizeof (dsphys->ds_guid)); 1101 } while (dsphys->ds_guid == 0); 1102 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1103 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1104 dsphys->ds_next_snap_obj = ds->ds_object; 1105 dsphys->ds_num_children = 1; 1106 dsphys->ds_creation_time = gethrestime_sec(); 1107 dsphys->ds_creation_txg = crtxg; 1108 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1109 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes; 1110 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1111 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1112 dsphys->ds_flags = ds->ds_phys->ds_flags; 1113 dsphys->ds_bp = ds->ds_phys->ds_bp; 1114 dmu_buf_rele(dbuf, FTAG); 1115 1116 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1117 if (ds->ds_prev) { 1118 uint64_t next_clones_obj = 1119 ds->ds_prev->ds_phys->ds_next_clones_obj; 1120 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1121 ds->ds_object || 1122 ds->ds_prev->ds_phys->ds_num_children > 1); 1123 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1124 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1125 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1126 ds->ds_prev->ds_phys->ds_creation_txg); 1127 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1128 } else if (next_clones_obj != 0) { 1129 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1130 dsphys->ds_next_snap_obj, tx); 1131 VERIFY0(zap_add_int(mos, 1132 next_clones_obj, dsobj, tx)); 1133 } 1134 } 1135 1136 /* 1137 * If we have a reference-reservation on this dataset, we will 1138 * need to increase the amount of refreservation being charged 1139 * since our unique space is going to zero. 1140 */ 1141 if (ds->ds_reserved) { 1142 int64_t delta; 1143 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1144 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 1145 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1146 delta, 0, 0, tx); 1147 } 1148 1149 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1150 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist, 1151 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx); 1152 dsl_deadlist_close(&ds->ds_deadlist); 1153 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj); 1154 dsl_deadlist_add_key(&ds->ds_deadlist, 1155 ds->ds_phys->ds_prev_snap_txg, tx); 1156 1157 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1158 ds->ds_phys->ds_prev_snap_obj = dsobj; 1159 ds->ds_phys->ds_prev_snap_txg = crtxg; 1160 ds->ds_phys->ds_unique_bytes = 0; 1161 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1162 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1163 1164 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1165 snapname, 8, 1, &dsobj, tx)); 1166 1167 if (ds->ds_prev) 1168 dsl_dataset_rele(ds->ds_prev, ds); 1169 VERIFY0(dsl_dataset_hold_obj(dp, 1170 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1171 1172 dsl_scan_ds_snapshotted(ds, tx); 1173 1174 dsl_dir_snap_cmtime_update(ds->ds_dir); 1175 1176 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1177} 1178 1179static void 1180dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1181{ 1182 dsl_dataset_snapshot_arg_t *ddsa = arg; 1183 dsl_pool_t *dp = dmu_tx_pool(tx); 1184 nvpair_t *pair; 1185 1186 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1187 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1188 dsl_dataset_t *ds; 1189 char *name, *atp; 1190 char dsname[MAXNAMELEN]; 1191 1192 name = nvpair_name(pair); 1193 atp = strchr(name, '@'); 1194 (void) strlcpy(dsname, name, atp - name + 1); 1195 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1196 1197 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1198 if (ddsa->ddsa_props != NULL) { 1199 dsl_props_set_sync_impl(ds->ds_prev, 1200 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1201 } 1202 dsl_dataset_rele(ds, FTAG); 1203 } 1204} 1205 1206/* 1207 * The snapshots must all be in the same pool. 1208 * All-or-nothing: if there are any failures, nothing will be modified. 1209 */ 1210int 1211dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1212{ 1213 dsl_dataset_snapshot_arg_t ddsa; 1214 nvpair_t *pair; 1215 boolean_t needsuspend; 1216 int error; 1217 spa_t *spa; 1218 char *firstname; 1219 nvlist_t *suspended = NULL; 1220 1221 pair = nvlist_next_nvpair(snaps, NULL); 1222 if (pair == NULL) 1223 return (0); 1224 firstname = nvpair_name(pair); 1225 1226 error = spa_open(firstname, &spa, FTAG); 1227 if (error != 0) 1228 return (error); 1229 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1230 spa_close(spa, FTAG); 1231 1232 if (needsuspend) { 1233 suspended = fnvlist_alloc(); 1234 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1235 pair = nvlist_next_nvpair(snaps, pair)) { 1236 char fsname[MAXNAMELEN]; 1237 char *snapname = nvpair_name(pair); 1238 char *atp; 1239 void *cookie; 1240 1241 atp = strchr(snapname, '@'); 1242 if (atp == NULL) { 1243 error = SET_ERROR(EINVAL); 1244 break; 1245 } 1246 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1247 1248 error = zil_suspend(fsname, &cookie); 1249 if (error != 0) 1250 break; 1251 fnvlist_add_uint64(suspended, fsname, 1252 (uintptr_t)cookie); 1253 } 1254 } 1255 1256 ddsa.ddsa_snaps = snaps; 1257 ddsa.ddsa_props = props; 1258 ddsa.ddsa_errors = errors; 1259 1260 if (error == 0) { 1261 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1262 dsl_dataset_snapshot_sync, &ddsa, 1263 fnvlist_num_pairs(snaps) * 3); 1264 } 1265 1266 if (suspended != NULL) { 1267 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1268 pair = nvlist_next_nvpair(suspended, pair)) { 1269 zil_resume((void *)(uintptr_t) 1270 fnvpair_value_uint64(pair)); 1271 } 1272 fnvlist_free(suspended); 1273 } 1274 1275#ifdef __FreeBSD__ 1276#ifdef _KERNEL 1277 if (error == 0) { 1278 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1279 pair = nvlist_next_nvpair(snaps, pair)) { 1280 char *snapname = nvpair_name(pair); 1281 zvol_create_minors(snapname); 1282 } 1283 } 1284#endif 1285#endif 1286 return (error); 1287} 1288 1289typedef struct dsl_dataset_snapshot_tmp_arg { 1290 const char *ddsta_fsname; 1291 const char *ddsta_snapname; 1292 minor_t ddsta_cleanup_minor; 1293 const char *ddsta_htag; 1294} dsl_dataset_snapshot_tmp_arg_t; 1295 1296static int 1297dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1298{ 1299 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1300 dsl_pool_t *dp = dmu_tx_pool(tx); 1301 dsl_dataset_t *ds; 1302 int error; 1303 1304 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1305 if (error != 0) 1306 return (error); 1307 1308 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1309 tx, B_FALSE); 1310 if (error != 0) { 1311 dsl_dataset_rele(ds, FTAG); 1312 return (error); 1313 } 1314 1315 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1316 dsl_dataset_rele(ds, FTAG); 1317 return (SET_ERROR(ENOTSUP)); 1318 } 1319 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1320 B_TRUE, tx); 1321 if (error != 0) { 1322 dsl_dataset_rele(ds, FTAG); 1323 return (error); 1324 } 1325 1326 dsl_dataset_rele(ds, FTAG); 1327 return (0); 1328} 1329 1330static void 1331dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1332{ 1333 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1334 dsl_pool_t *dp = dmu_tx_pool(tx); 1335 dsl_dataset_t *ds; 1336 1337 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1338 1339 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1340 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1341 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1342 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1343 1344 dsl_dataset_rele(ds, FTAG); 1345} 1346 1347int 1348dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1349 minor_t cleanup_minor, const char *htag) 1350{ 1351 dsl_dataset_snapshot_tmp_arg_t ddsta; 1352 int error; 1353 spa_t *spa; 1354 boolean_t needsuspend; 1355 void *cookie; 1356 1357 ddsta.ddsta_fsname = fsname; 1358 ddsta.ddsta_snapname = snapname; 1359 ddsta.ddsta_cleanup_minor = cleanup_minor; 1360 ddsta.ddsta_htag = htag; 1361 1362 error = spa_open(fsname, &spa, FTAG); 1363 if (error != 0) 1364 return (error); 1365 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1366 spa_close(spa, FTAG); 1367 1368 if (needsuspend) { 1369 error = zil_suspend(fsname, &cookie); 1370 if (error != 0) 1371 return (error); 1372 } 1373 1374 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1375 dsl_dataset_snapshot_tmp_sync, &ddsta, 3); 1376 1377 if (needsuspend) 1378 zil_resume(cookie); 1379 return (error); 1380} 1381 1382 1383void 1384dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1385{ 1386 ASSERT(dmu_tx_is_syncing(tx)); 1387 ASSERT(ds->ds_objset != NULL); 1388 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1389 1390 /* 1391 * in case we had to change ds_fsid_guid when we opened it, 1392 * sync it out now. 1393 */ 1394 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1395 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1396 1397 dmu_objset_sync(ds->ds_objset, zio, tx); 1398} 1399 1400static void 1401get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1402{ 1403 uint64_t count = 0; 1404 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1405 zap_cursor_t zc; 1406 zap_attribute_t za; 1407 nvlist_t *propval = fnvlist_alloc(); 1408 nvlist_t *val = fnvlist_alloc(); 1409 1410 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1411 1412 /* 1413 * There may be missing entries in ds_next_clones_obj 1414 * due to a bug in a previous version of the code. 1415 * Only trust it if it has the right number of entries. 1416 */ 1417 if (ds->ds_phys->ds_next_clones_obj != 0) { 1418 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 1419 &count)); 1420 } 1421 if (count != ds->ds_phys->ds_num_children - 1) 1422 goto fail; 1423 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj); 1424 zap_cursor_retrieve(&zc, &za) == 0; 1425 zap_cursor_advance(&zc)) { 1426 dsl_dataset_t *clone; 1427 char buf[ZFS_MAXNAMELEN]; 1428 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1429 za.za_first_integer, FTAG, &clone)); 1430 dsl_dir_name(clone->ds_dir, buf); 1431 fnvlist_add_boolean(val, buf); 1432 dsl_dataset_rele(clone, FTAG); 1433 } 1434 zap_cursor_fini(&zc); 1435 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1436 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1437fail: 1438 nvlist_free(val); 1439 nvlist_free(propval); 1440} 1441 1442void 1443dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1444{ 1445 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1446 uint64_t refd, avail, uobjs, aobjs, ratio; 1447 1448 ASSERT(dsl_pool_config_held(dp)); 1449 1450 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1451 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1452 ds->ds_phys->ds_compressed_bytes); 1453 1454 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1455 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1456 ds->ds_phys->ds_uncompressed_bytes); 1457 1458 if (dsl_dataset_is_snapshot(ds)) { 1459 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1460 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1461 ds->ds_phys->ds_unique_bytes); 1462 get_clones_stat(ds, nv); 1463 } else { 1464 dsl_dir_stats(ds->ds_dir, nv); 1465 } 1466 1467 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1468 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1469 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1470 1471 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1472 ds->ds_phys->ds_creation_time); 1473 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1474 ds->ds_phys->ds_creation_txg); 1475 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1476 ds->ds_quota); 1477 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1478 ds->ds_reserved); 1479 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1480 ds->ds_phys->ds_guid); 1481 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1482 ds->ds_phys->ds_unique_bytes); 1483 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1484 ds->ds_object); 1485 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1486 ds->ds_userrefs); 1487 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1488 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1489 1490 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1491 uint64_t written, comp, uncomp; 1492 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1493 dsl_dataset_t *prev; 1494 1495 int err = dsl_dataset_hold_obj(dp, 1496 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev); 1497 if (err == 0) { 1498 err = dsl_dataset_space_written(prev, ds, &written, 1499 &comp, &uncomp); 1500 dsl_dataset_rele(prev, FTAG); 1501 if (err == 0) { 1502 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1503 written); 1504 } 1505 } 1506 } 1507} 1508 1509void 1510dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1511{ 1512 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1513 ASSERT(dsl_pool_config_held(dp)); 1514 1515 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1516 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1517 stat->dds_guid = ds->ds_phys->ds_guid; 1518 stat->dds_origin[0] = '\0'; 1519 if (dsl_dataset_is_snapshot(ds)) { 1520 stat->dds_is_snapshot = B_TRUE; 1521 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1522 } else { 1523 stat->dds_is_snapshot = B_FALSE; 1524 stat->dds_num_clones = 0; 1525 1526 if (dsl_dir_is_clone(ds->ds_dir)) { 1527 dsl_dataset_t *ods; 1528 1529 VERIFY0(dsl_dataset_hold_obj(dp, 1530 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1531 dsl_dataset_name(ods, stat->dds_origin); 1532 dsl_dataset_rele(ods, FTAG); 1533 } 1534 } 1535} 1536 1537uint64_t 1538dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1539{ 1540 return (ds->ds_fsid_guid); 1541} 1542 1543void 1544dsl_dataset_space(dsl_dataset_t *ds, 1545 uint64_t *refdbytesp, uint64_t *availbytesp, 1546 uint64_t *usedobjsp, uint64_t *availobjsp) 1547{ 1548 *refdbytesp = ds->ds_phys->ds_referenced_bytes; 1549 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1550 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1551 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1552 if (ds->ds_quota != 0) { 1553 /* 1554 * Adjust available bytes according to refquota 1555 */ 1556 if (*refdbytesp < ds->ds_quota) 1557 *availbytesp = MIN(*availbytesp, 1558 ds->ds_quota - *refdbytesp); 1559 else 1560 *availbytesp = 0; 1561 } 1562 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1563 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1564} 1565 1566boolean_t 1567dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1568{ 1569 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1570 1571 ASSERT(dsl_pool_config_held(dp)); 1572 if (snap == NULL) 1573 return (B_FALSE); 1574 if (ds->ds_phys->ds_bp.blk_birth > 1575 snap->ds_phys->ds_creation_txg) { 1576 objset_t *os, *os_snap; 1577 /* 1578 * It may be that only the ZIL differs, because it was 1579 * reset in the head. Don't count that as being 1580 * modified. 1581 */ 1582 if (dmu_objset_from_ds(ds, &os) != 0) 1583 return (B_TRUE); 1584 if (dmu_objset_from_ds(snap, &os_snap) != 0) 1585 return (B_TRUE); 1586 return (bcmp(&os->os_phys->os_meta_dnode, 1587 &os_snap->os_phys->os_meta_dnode, 1588 sizeof (os->os_phys->os_meta_dnode)) != 0); 1589 } 1590 return (B_FALSE); 1591} 1592 1593typedef struct dsl_dataset_rename_snapshot_arg { 1594 const char *ddrsa_fsname; 1595 const char *ddrsa_oldsnapname; 1596 const char *ddrsa_newsnapname; 1597 boolean_t ddrsa_recursive; 1598 dmu_tx_t *ddrsa_tx; 1599} dsl_dataset_rename_snapshot_arg_t; 1600 1601/* ARGSUSED */ 1602static int 1603dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1604 dsl_dataset_t *hds, void *arg) 1605{ 1606 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1607 int error; 1608 uint64_t val; 1609 1610 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1611 if (error != 0) { 1612 /* ignore nonexistent snapshots */ 1613 return (error == ENOENT ? 0 : error); 1614 } 1615 1616 /* new name should not exist */ 1617 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 1618 if (error == 0) 1619 error = SET_ERROR(EEXIST); 1620 else if (error == ENOENT) 1621 error = 0; 1622 1623 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1624 if (dsl_dir_namelen(hds->ds_dir) + 1 + 1625 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN) 1626 error = SET_ERROR(ENAMETOOLONG); 1627 1628 return (error); 1629} 1630 1631static int 1632dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 1633{ 1634 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1635 dsl_pool_t *dp = dmu_tx_pool(tx); 1636 dsl_dataset_t *hds; 1637 int error; 1638 1639 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 1640 if (error != 0) 1641 return (error); 1642 1643 if (ddrsa->ddrsa_recursive) { 1644 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1645 dsl_dataset_rename_snapshot_check_impl, ddrsa, 1646 DS_FIND_CHILDREN); 1647 } else { 1648 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 1649 } 1650 dsl_dataset_rele(hds, FTAG); 1651 return (error); 1652} 1653 1654static int 1655dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 1656 dsl_dataset_t *hds, void *arg) 1657{ 1658#ifdef __FreeBSD__ 1659#ifdef _KERNEL 1660 char *oldname, *newname; 1661#endif 1662#endif 1663 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1664 dsl_dataset_t *ds; 1665 uint64_t val; 1666 dmu_tx_t *tx = ddrsa->ddrsa_tx; 1667 int error; 1668 1669 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1670 ASSERT(error == 0 || error == ENOENT); 1671 if (error == ENOENT) { 1672 /* ignore nonexistent snapshots */ 1673 return (0); 1674 } 1675 1676 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 1677 1678 /* log before we change the name */ 1679 spa_history_log_internal_ds(ds, "rename", tx, 1680 "-> @%s", ddrsa->ddrsa_newsnapname); 1681 1682 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx)); 1683 mutex_enter(&ds->ds_lock); 1684 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 1685 mutex_exit(&ds->ds_lock); 1686 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj, 1687 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 1688 1689#ifdef __FreeBSD__ 1690#ifdef _KERNEL 1691 oldname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 1692 newname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 1693 snprintf(oldname, MAXPATHLEN, "%s@%s", ddrsa->ddrsa_fsname, 1694 ddrsa->ddrsa_oldsnapname); 1695 snprintf(newname, MAXPATHLEN, "%s@%s", ddrsa->ddrsa_fsname, 1696 ddrsa->ddrsa_newsnapname); 1697 zfsvfs_update_fromname(oldname, newname); 1698 zvol_rename_minors(oldname, newname); 1699 kmem_free(newname, MAXPATHLEN); 1700 kmem_free(oldname, MAXPATHLEN); 1701#endif 1702#endif 1703 dsl_dataset_rele(ds, FTAG); 1704 1705 return (0); 1706} 1707 1708static void 1709dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 1710{ 1711 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1712 dsl_pool_t *dp = dmu_tx_pool(tx); 1713 dsl_dataset_t *hds; 1714 1715 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 1716 ddrsa->ddrsa_tx = tx; 1717 if (ddrsa->ddrsa_recursive) { 1718 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1719 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 1720 DS_FIND_CHILDREN)); 1721 } else { 1722 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 1723 } 1724 dsl_dataset_rele(hds, FTAG); 1725} 1726 1727int 1728dsl_dataset_rename_snapshot(const char *fsname, 1729 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 1730{ 1731 dsl_dataset_rename_snapshot_arg_t ddrsa; 1732 1733 ddrsa.ddrsa_fsname = fsname; 1734 ddrsa.ddrsa_oldsnapname = oldsnapname; 1735 ddrsa.ddrsa_newsnapname = newsnapname; 1736 ddrsa.ddrsa_recursive = recursive; 1737 1738 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 1739 dsl_dataset_rename_snapshot_sync, &ddrsa, 1)); 1740} 1741 1742/* 1743 * If we're doing an ownership handoff, we need to make sure that there is 1744 * only one long hold on the dataset. We're not allowed to change anything here 1745 * so we don't permanently release the long hold or regular hold here. We want 1746 * to do this only when syncing to avoid the dataset unexpectedly going away 1747 * when we release the long hold. 1748 */ 1749static int 1750dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 1751{ 1752 boolean_t held; 1753 1754 if (!dmu_tx_is_syncing(tx)) 1755 return (0); 1756 1757 if (owner != NULL) { 1758 VERIFY3P(ds->ds_owner, ==, owner); 1759 dsl_dataset_long_rele(ds, owner); 1760 } 1761 1762 held = dsl_dataset_long_held(ds); 1763 1764 if (owner != NULL) 1765 dsl_dataset_long_hold(ds, owner); 1766 1767 if (held) 1768 return (SET_ERROR(EBUSY)); 1769 1770 return (0); 1771} 1772 1773typedef struct dsl_dataset_rollback_arg { 1774 const char *ddra_fsname; 1775 void *ddra_owner; 1776 nvlist_t *ddra_result; 1777} dsl_dataset_rollback_arg_t; 1778 1779static int 1780dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 1781{ 1782 dsl_dataset_rollback_arg_t *ddra = arg; 1783 dsl_pool_t *dp = dmu_tx_pool(tx); 1784 dsl_dataset_t *ds; 1785 int64_t unused_refres_delta; 1786 int error; 1787 1788 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 1789 if (error != 0) 1790 return (error); 1791 1792 /* must not be a snapshot */ 1793 if (dsl_dataset_is_snapshot(ds)) { 1794 dsl_dataset_rele(ds, FTAG); 1795 return (SET_ERROR(EINVAL)); 1796 } 1797 1798 /* must have a most recent snapshot */ 1799 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) { 1800 dsl_dataset_rele(ds, FTAG); 1801 return (SET_ERROR(EINVAL)); 1802 } 1803 1804 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 1805 if (error != 0) { 1806 dsl_dataset_rele(ds, FTAG); 1807 return (error); 1808 } 1809 1810 /* 1811 * Check if the snap we are rolling back to uses more than 1812 * the refquota. 1813 */ 1814 if (ds->ds_quota != 0 && 1815 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) { 1816 dsl_dataset_rele(ds, FTAG); 1817 return (SET_ERROR(EDQUOT)); 1818 } 1819 1820 /* 1821 * When we do the clone swap, we will temporarily use more space 1822 * due to the refreservation (the head will no longer have any 1823 * unique space, so the entire amount of the refreservation will need 1824 * to be free). We will immediately destroy the clone, freeing 1825 * this space, but the freeing happens over many txg's. 1826 */ 1827 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 1828 ds->ds_phys->ds_unique_bytes); 1829 1830 if (unused_refres_delta > 0 && 1831 unused_refres_delta > 1832 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 1833 dsl_dataset_rele(ds, FTAG); 1834 return (SET_ERROR(ENOSPC)); 1835 } 1836 1837 dsl_dataset_rele(ds, FTAG); 1838 return (0); 1839} 1840 1841static void 1842dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 1843{ 1844 dsl_dataset_rollback_arg_t *ddra = arg; 1845 dsl_pool_t *dp = dmu_tx_pool(tx); 1846 dsl_dataset_t *ds, *clone; 1847 uint64_t cloneobj; 1848 char namebuf[ZFS_MAXNAMELEN]; 1849 1850 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 1851 1852 dsl_dataset_name(ds->ds_prev, namebuf); 1853 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 1854 1855 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 1856 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 1857 1858 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 1859 1860 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 1861 dsl_dataset_zero_zil(ds, tx); 1862 1863 dsl_destroy_head_sync_impl(clone, tx); 1864 1865 dsl_dataset_rele(clone, FTAG); 1866 dsl_dataset_rele(ds, FTAG); 1867} 1868 1869/* 1870 * Rolls back the given filesystem or volume to the most recent snapshot. 1871 * The name of the most recent snapshot will be returned under key "target" 1872 * in the result nvlist. 1873 * 1874 * If owner != NULL: 1875 * - The existing dataset MUST be owned by the specified owner at entry 1876 * - Upon return, dataset will still be held by the same owner, whether we 1877 * succeed or not. 1878 * 1879 * This mode is required any time the existing filesystem is mounted. See 1880 * notes above zfs_suspend_fs() for further details. 1881 */ 1882int 1883dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result) 1884{ 1885 dsl_dataset_rollback_arg_t ddra; 1886 1887 ddra.ddra_fsname = fsname; 1888 ddra.ddra_owner = owner; 1889 ddra.ddra_result = result; 1890 1891 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 1892 dsl_dataset_rollback_sync, &ddra, 1)); 1893} 1894 1895struct promotenode { 1896 list_node_t link; 1897 dsl_dataset_t *ds; 1898}; 1899 1900typedef struct dsl_dataset_promote_arg { 1901 const char *ddpa_clonename; 1902 dsl_dataset_t *ddpa_clone; 1903 list_t shared_snaps, origin_snaps, clone_snaps; 1904 dsl_dataset_t *origin_origin; /* origin of the origin */ 1905 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 1906 char *err_ds; 1907} dsl_dataset_promote_arg_t; 1908 1909static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 1910static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 1911 void *tag); 1912static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 1913 1914static int 1915dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 1916{ 1917 dsl_dataset_promote_arg_t *ddpa = arg; 1918 dsl_pool_t *dp = dmu_tx_pool(tx); 1919 dsl_dataset_t *hds; 1920 struct promotenode *snap; 1921 dsl_dataset_t *origin_ds; 1922 int err; 1923 uint64_t unused; 1924 1925 err = promote_hold(ddpa, dp, FTAG); 1926 if (err != 0) 1927 return (err); 1928 1929 hds = ddpa->ddpa_clone; 1930 1931 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) { 1932 promote_rele(ddpa, FTAG); 1933 return (SET_ERROR(EXDEV)); 1934 } 1935 1936 /* 1937 * Compute and check the amount of space to transfer. Since this is 1938 * so expensive, don't do the preliminary check. 1939 */ 1940 if (!dmu_tx_is_syncing(tx)) { 1941 promote_rele(ddpa, FTAG); 1942 return (0); 1943 } 1944 1945 snap = list_head(&ddpa->shared_snaps); 1946 origin_ds = snap->ds; 1947 1948 /* compute origin's new unique space */ 1949 snap = list_tail(&ddpa->clone_snaps); 1950 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 1951 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 1952 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, 1953 &ddpa->unique, &unused, &unused); 1954 1955 /* 1956 * Walk the snapshots that we are moving 1957 * 1958 * Compute space to transfer. Consider the incremental changes 1959 * to used by each snapshot: 1960 * (my used) = (prev's used) + (blocks born) - (blocks killed) 1961 * So each snapshot gave birth to: 1962 * (blocks born) = (my used) - (prev's used) + (blocks killed) 1963 * So a sequence would look like: 1964 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 1965 * Which simplifies to: 1966 * uN + kN + kN-1 + ... + k1 + k0 1967 * Note however, if we stop before we reach the ORIGIN we get: 1968 * uN + kN + kN-1 + ... + kM - uM-1 1969 */ 1970 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes; 1971 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes; 1972 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 1973 for (snap = list_head(&ddpa->shared_snaps); snap; 1974 snap = list_next(&ddpa->shared_snaps, snap)) { 1975 uint64_t val, dlused, dlcomp, dluncomp; 1976 dsl_dataset_t *ds = snap->ds; 1977 1978 /* 1979 * If there are long holds, we won't be able to evict 1980 * the objset. 1981 */ 1982 if (dsl_dataset_long_held(ds)) { 1983 err = SET_ERROR(EBUSY); 1984 goto out; 1985 } 1986 1987 /* Check that the snapshot name does not conflict */ 1988 VERIFY0(dsl_dataset_get_snapname(ds)); 1989 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 1990 if (err == 0) { 1991 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 1992 err = SET_ERROR(EEXIST); 1993 goto out; 1994 } 1995 if (err != ENOENT) 1996 goto out; 1997 1998 /* The very first snapshot does not have a deadlist */ 1999 if (ds->ds_phys->ds_prev_snap_obj == 0) 2000 continue; 2001 2002 dsl_deadlist_space(&ds->ds_deadlist, 2003 &dlused, &dlcomp, &dluncomp); 2004 ddpa->used += dlused; 2005 ddpa->comp += dlcomp; 2006 ddpa->uncomp += dluncomp; 2007 } 2008 2009 /* 2010 * If we are a clone of a clone then we never reached ORIGIN, 2011 * so we need to subtract out the clone origin's used space. 2012 */ 2013 if (ddpa->origin_origin) { 2014 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes; 2015 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes; 2016 ddpa->uncomp -= 2017 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes; 2018 } 2019 2020 /* Check that there is enough space here */ 2021 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2022 ddpa->used); 2023 if (err != 0) 2024 goto out; 2025 2026 /* 2027 * Compute the amounts of space that will be used by snapshots 2028 * after the promotion (for both origin and clone). For each, 2029 * it is the amount of space that will be on all of their 2030 * deadlists (that was not born before their new origin). 2031 */ 2032 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2033 uint64_t space; 2034 2035 /* 2036 * Note, typically this will not be a clone of a clone, 2037 * so dd_origin_txg will be < TXG_INITIAL, so 2038 * these snaplist_space() -> dsl_deadlist_space_range() 2039 * calls will be fast because they do not have to 2040 * iterate over all bps. 2041 */ 2042 snap = list_head(&ddpa->origin_snaps); 2043 err = snaplist_space(&ddpa->shared_snaps, 2044 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 2045 if (err != 0) 2046 goto out; 2047 2048 err = snaplist_space(&ddpa->clone_snaps, 2049 snap->ds->ds_dir->dd_origin_txg, &space); 2050 if (err != 0) 2051 goto out; 2052 ddpa->cloneusedsnap += space; 2053 } 2054 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2055 err = snaplist_space(&ddpa->origin_snaps, 2056 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap); 2057 if (err != 0) 2058 goto out; 2059 } 2060 2061out: 2062 promote_rele(ddpa, FTAG); 2063 return (err); 2064} 2065 2066static void 2067dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2068{ 2069 dsl_dataset_promote_arg_t *ddpa = arg; 2070 dsl_pool_t *dp = dmu_tx_pool(tx); 2071 dsl_dataset_t *hds; 2072 struct promotenode *snap; 2073 dsl_dataset_t *origin_ds; 2074 dsl_dataset_t *origin_head; 2075 dsl_dir_t *dd; 2076 dsl_dir_t *odd = NULL; 2077 uint64_t oldnext_obj; 2078 int64_t delta; 2079 2080 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2081 hds = ddpa->ddpa_clone; 2082 2083 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE); 2084 2085 snap = list_head(&ddpa->shared_snaps); 2086 origin_ds = snap->ds; 2087 dd = hds->ds_dir; 2088 2089 snap = list_head(&ddpa->origin_snaps); 2090 origin_head = snap->ds; 2091 2092 /* 2093 * We need to explicitly open odd, since origin_ds's dd will be 2094 * changing. 2095 */ 2096 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2097 NULL, FTAG, &odd)); 2098 2099 /* change origin's next snap */ 2100 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2101 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2102 snap = list_tail(&ddpa->clone_snaps); 2103 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2104 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2105 2106 /* change the origin's next clone */ 2107 if (origin_ds->ds_phys->ds_next_clones_obj) { 2108 dsl_dataset_remove_from_next_clones(origin_ds, 2109 snap->ds->ds_object, tx); 2110 VERIFY0(zap_add_int(dp->dp_meta_objset, 2111 origin_ds->ds_phys->ds_next_clones_obj, 2112 oldnext_obj, tx)); 2113 } 2114 2115 /* change origin */ 2116 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2117 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2118 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2119 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2120 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2121 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2122 origin_head->ds_dir->dd_origin_txg = 2123 origin_ds->ds_phys->ds_creation_txg; 2124 2125 /* change dd_clone entries */ 2126 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2127 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2128 odd->dd_phys->dd_clones, hds->ds_object, tx)); 2129 VERIFY0(zap_add_int(dp->dp_meta_objset, 2130 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2131 hds->ds_object, tx)); 2132 2133 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2134 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2135 origin_head->ds_object, tx)); 2136 if (dd->dd_phys->dd_clones == 0) { 2137 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset, 2138 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 2139 } 2140 VERIFY0(zap_add_int(dp->dp_meta_objset, 2141 dd->dd_phys->dd_clones, origin_head->ds_object, tx)); 2142 } 2143 2144 /* move snapshots to this dir */ 2145 for (snap = list_head(&ddpa->shared_snaps); snap; 2146 snap = list_next(&ddpa->shared_snaps, snap)) { 2147 dsl_dataset_t *ds = snap->ds; 2148 2149 /* 2150 * Property callbacks are registered to a particular 2151 * dsl_dir. Since ours is changing, evict the objset 2152 * so that they will be unregistered from the old dsl_dir. 2153 */ 2154 if (ds->ds_objset) { 2155 dmu_objset_evict(ds->ds_objset); 2156 ds->ds_objset = NULL; 2157 } 2158 2159 /* move snap name entry */ 2160 VERIFY0(dsl_dataset_get_snapname(ds)); 2161 VERIFY0(dsl_dataset_snap_remove(origin_head, 2162 ds->ds_snapname, tx)); 2163 VERIFY0(zap_add(dp->dp_meta_objset, 2164 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2165 8, 1, &ds->ds_object, tx)); 2166 2167 /* change containing dsl_dir */ 2168 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2169 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2170 ds->ds_phys->ds_dir_obj = dd->dd_object; 2171 ASSERT3P(ds->ds_dir, ==, odd); 2172 dsl_dir_rele(ds->ds_dir, ds); 2173 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2174 NULL, ds, &ds->ds_dir)); 2175 2176 /* move any clone references */ 2177 if (ds->ds_phys->ds_next_clones_obj && 2178 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2179 zap_cursor_t zc; 2180 zap_attribute_t za; 2181 2182 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2183 ds->ds_phys->ds_next_clones_obj); 2184 zap_cursor_retrieve(&zc, &za) == 0; 2185 zap_cursor_advance(&zc)) { 2186 dsl_dataset_t *cnds; 2187 uint64_t o; 2188 2189 if (za.za_first_integer == oldnext_obj) { 2190 /* 2191 * We've already moved the 2192 * origin's reference. 2193 */ 2194 continue; 2195 } 2196 2197 VERIFY0(dsl_dataset_hold_obj(dp, 2198 za.za_first_integer, FTAG, &cnds)); 2199 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj; 2200 2201 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2202 odd->dd_phys->dd_clones, o, tx)); 2203 VERIFY0(zap_add_int(dp->dp_meta_objset, 2204 dd->dd_phys->dd_clones, o, tx)); 2205 dsl_dataset_rele(cnds, FTAG); 2206 } 2207 zap_cursor_fini(&zc); 2208 } 2209 2210 ASSERT(!dsl_prop_hascb(ds)); 2211 } 2212 2213 /* 2214 * Change space accounting. 2215 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2216 * both be valid, or both be 0 (resulting in delta == 0). This 2217 * is true for each of {clone,origin} independently. 2218 */ 2219 2220 delta = ddpa->cloneusedsnap - 2221 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2222 ASSERT3S(delta, >=, 0); 2223 ASSERT3U(ddpa->used, >=, delta); 2224 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2225 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2226 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2227 2228 delta = ddpa->originusedsnap - 2229 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2230 ASSERT3S(delta, <=, 0); 2231 ASSERT3U(ddpa->used, >=, -delta); 2232 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2233 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2234 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2235 2236 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique; 2237 2238 /* log history record */ 2239 spa_history_log_internal_ds(hds, "promote", tx, ""); 2240 2241 dsl_dir_rele(odd, FTAG); 2242 promote_rele(ddpa, FTAG); 2243} 2244 2245/* 2246 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2247 * (exclusive) and last_obj (inclusive). The list will be in reverse 2248 * order (last_obj will be the list_head()). If first_obj == 0, do all 2249 * snapshots back to this dataset's origin. 2250 */ 2251static int 2252snaplist_make(dsl_pool_t *dp, 2253 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2254{ 2255 uint64_t obj = last_obj; 2256 2257 list_create(l, sizeof (struct promotenode), 2258 offsetof(struct promotenode, link)); 2259 2260 while (obj != first_obj) { 2261 dsl_dataset_t *ds; 2262 struct promotenode *snap; 2263 int err; 2264 2265 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2266 ASSERT(err != ENOENT); 2267 if (err != 0) 2268 return (err); 2269 2270 if (first_obj == 0) 2271 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2272 2273 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2274 snap->ds = ds; 2275 list_insert_tail(l, snap); 2276 obj = ds->ds_phys->ds_prev_snap_obj; 2277 } 2278 2279 return (0); 2280} 2281 2282static int 2283snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2284{ 2285 struct promotenode *snap; 2286 2287 *spacep = 0; 2288 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2289 uint64_t used, comp, uncomp; 2290 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2291 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2292 *spacep += used; 2293 } 2294 return (0); 2295} 2296 2297static void 2298snaplist_destroy(list_t *l, void *tag) 2299{ 2300 struct promotenode *snap; 2301 2302 if (l == NULL || !list_link_active(&l->list_head)) 2303 return; 2304 2305 while ((snap = list_tail(l)) != NULL) { 2306 list_remove(l, snap); 2307 dsl_dataset_rele(snap->ds, tag); 2308 kmem_free(snap, sizeof (*snap)); 2309 } 2310 list_destroy(l); 2311} 2312 2313static int 2314promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2315{ 2316 int error; 2317 dsl_dir_t *dd; 2318 struct promotenode *snap; 2319 2320 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2321 &ddpa->ddpa_clone); 2322 if (error != 0) 2323 return (error); 2324 dd = ddpa->ddpa_clone->ds_dir; 2325 2326 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) || 2327 !dsl_dir_is_clone(dd)) { 2328 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2329 return (SET_ERROR(EINVAL)); 2330 } 2331 2332 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj, 2333 &ddpa->shared_snaps, tag); 2334 if (error != 0) 2335 goto out; 2336 2337 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2338 &ddpa->clone_snaps, tag); 2339 if (error != 0) 2340 goto out; 2341 2342 snap = list_head(&ddpa->shared_snaps); 2343 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2344 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj, 2345 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, 2346 &ddpa->origin_snaps, tag); 2347 if (error != 0) 2348 goto out; 2349 2350 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) { 2351 error = dsl_dataset_hold_obj(dp, 2352 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2353 tag, &ddpa->origin_origin); 2354 if (error != 0) 2355 goto out; 2356 } 2357out: 2358 if (error != 0) 2359 promote_rele(ddpa, tag); 2360 return (error); 2361} 2362 2363static void 2364promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2365{ 2366 snaplist_destroy(&ddpa->shared_snaps, tag); 2367 snaplist_destroy(&ddpa->clone_snaps, tag); 2368 snaplist_destroy(&ddpa->origin_snaps, tag); 2369 if (ddpa->origin_origin != NULL) 2370 dsl_dataset_rele(ddpa->origin_origin, tag); 2371 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2372} 2373 2374/* 2375 * Promote a clone. 2376 * 2377 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2378 * in with the name. (It must be at least MAXNAMELEN bytes long.) 2379 */ 2380int 2381dsl_dataset_promote(const char *name, char *conflsnap) 2382{ 2383 dsl_dataset_promote_arg_t ddpa = { 0 }; 2384 uint64_t numsnaps; 2385 int error; 2386 objset_t *os; 2387 2388 /* 2389 * We will modify space proportional to the number of 2390 * snapshots. Compute numsnaps. 2391 */ 2392 error = dmu_objset_hold(name, FTAG, &os); 2393 if (error != 0) 2394 return (error); 2395 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2396 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps); 2397 dmu_objset_rele(os, FTAG); 2398 if (error != 0) 2399 return (error); 2400 2401 ddpa.ddpa_clonename = name; 2402 ddpa.err_ds = conflsnap; 2403 2404 return (dsl_sync_task(name, dsl_dataset_promote_check, 2405 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps)); 2406} 2407 2408int 2409dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2410 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2411{ 2412 int64_t unused_refres_delta; 2413 2414 /* they should both be heads */ 2415 if (dsl_dataset_is_snapshot(clone) || 2416 dsl_dataset_is_snapshot(origin_head)) 2417 return (SET_ERROR(EINVAL)); 2418 2419 /* if we are not forcing, the branch point should be just before them */ 2420 if (!force && clone->ds_prev != origin_head->ds_prev) 2421 return (SET_ERROR(EINVAL)); 2422 2423 /* clone should be the clone (unless they are unrelated) */ 2424 if (clone->ds_prev != NULL && 2425 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2426 origin_head->ds_dir != clone->ds_prev->ds_dir) 2427 return (SET_ERROR(EINVAL)); 2428 2429 /* the clone should be a child of the origin */ 2430 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2431 return (SET_ERROR(EINVAL)); 2432 2433 /* origin_head shouldn't be modified unless 'force' */ 2434 if (!force && 2435 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2436 return (SET_ERROR(ETXTBSY)); 2437 2438 /* origin_head should have no long holds (e.g. is not mounted) */ 2439 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2440 return (SET_ERROR(EBUSY)); 2441 2442 /* check amount of any unconsumed refreservation */ 2443 unused_refres_delta = 2444 (int64_t)MIN(origin_head->ds_reserved, 2445 origin_head->ds_phys->ds_unique_bytes) - 2446 (int64_t)MIN(origin_head->ds_reserved, 2447 clone->ds_phys->ds_unique_bytes); 2448 2449 if (unused_refres_delta > 0 && 2450 unused_refres_delta > 2451 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2452 return (SET_ERROR(ENOSPC)); 2453 2454 /* clone can't be over the head's refquota */ 2455 if (origin_head->ds_quota != 0 && 2456 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota) 2457 return (SET_ERROR(EDQUOT)); 2458 2459 return (0); 2460} 2461 2462void 2463dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2464 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2465{ 2466 dsl_pool_t *dp = dmu_tx_pool(tx); 2467 int64_t unused_refres_delta; 2468 2469 ASSERT(clone->ds_reserved == 0); 2470 ASSERT(origin_head->ds_quota == 0 || 2471 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota); 2472 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2473 2474 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2475 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2476 2477 if (clone->ds_objset != NULL) { 2478 dmu_objset_evict(clone->ds_objset); 2479 clone->ds_objset = NULL; 2480 } 2481 2482 if (origin_head->ds_objset != NULL) { 2483 dmu_objset_evict(origin_head->ds_objset); 2484 origin_head->ds_objset = NULL; 2485 } 2486 2487 unused_refres_delta = 2488 (int64_t)MIN(origin_head->ds_reserved, 2489 origin_head->ds_phys->ds_unique_bytes) - 2490 (int64_t)MIN(origin_head->ds_reserved, 2491 clone->ds_phys->ds_unique_bytes); 2492 2493 /* 2494 * Reset origin's unique bytes, if it exists. 2495 */ 2496 if (clone->ds_prev) { 2497 dsl_dataset_t *origin = clone->ds_prev; 2498 uint64_t comp, uncomp; 2499 2500 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2501 dsl_deadlist_space_range(&clone->ds_deadlist, 2502 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2503 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp); 2504 } 2505 2506 /* swap blkptrs */ 2507 { 2508 blkptr_t tmp; 2509 tmp = origin_head->ds_phys->ds_bp; 2510 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp; 2511 clone->ds_phys->ds_bp = tmp; 2512 } 2513 2514 /* set dd_*_bytes */ 2515 { 2516 int64_t dused, dcomp, duncomp; 2517 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2518 uint64_t odl_used, odl_comp, odl_uncomp; 2519 2520 ASSERT3U(clone->ds_dir->dd_phys-> 2521 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2522 2523 dsl_deadlist_space(&clone->ds_deadlist, 2524 &cdl_used, &cdl_comp, &cdl_uncomp); 2525 dsl_deadlist_space(&origin_head->ds_deadlist, 2526 &odl_used, &odl_comp, &odl_uncomp); 2527 2528 dused = clone->ds_phys->ds_referenced_bytes + cdl_used - 2529 (origin_head->ds_phys->ds_referenced_bytes + odl_used); 2530 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp - 2531 (origin_head->ds_phys->ds_compressed_bytes + odl_comp); 2532 duncomp = clone->ds_phys->ds_uncompressed_bytes + 2533 cdl_uncomp - 2534 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2535 2536 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 2537 dused, dcomp, duncomp, tx); 2538 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 2539 -dused, -dcomp, -duncomp, tx); 2540 2541 /* 2542 * The difference in the space used by snapshots is the 2543 * difference in snapshot space due to the head's 2544 * deadlist (since that's the only thing that's 2545 * changing that affects the snapused). 2546 */ 2547 dsl_deadlist_space_range(&clone->ds_deadlist, 2548 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2549 &cdl_used, &cdl_comp, &cdl_uncomp); 2550 dsl_deadlist_space_range(&origin_head->ds_deadlist, 2551 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2552 &odl_used, &odl_comp, &odl_uncomp); 2553 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 2554 DD_USED_HEAD, DD_USED_SNAP, tx); 2555 } 2556 2557 /* swap ds_*_bytes */ 2558 SWITCH64(origin_head->ds_phys->ds_referenced_bytes, 2559 clone->ds_phys->ds_referenced_bytes); 2560 SWITCH64(origin_head->ds_phys->ds_compressed_bytes, 2561 clone->ds_phys->ds_compressed_bytes); 2562 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes, 2563 clone->ds_phys->ds_uncompressed_bytes); 2564 SWITCH64(origin_head->ds_phys->ds_unique_bytes, 2565 clone->ds_phys->ds_unique_bytes); 2566 2567 /* apply any parent delta for change in unconsumed refreservation */ 2568 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 2569 unused_refres_delta, 0, 0, tx); 2570 2571 /* 2572 * Swap deadlists. 2573 */ 2574 dsl_deadlist_close(&clone->ds_deadlist); 2575 dsl_deadlist_close(&origin_head->ds_deadlist); 2576 SWITCH64(origin_head->ds_phys->ds_deadlist_obj, 2577 clone->ds_phys->ds_deadlist_obj); 2578 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 2579 clone->ds_phys->ds_deadlist_obj); 2580 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 2581 origin_head->ds_phys->ds_deadlist_obj); 2582 2583 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 2584 2585 spa_history_log_internal_ds(clone, "clone swap", tx, 2586 "parent=%s", origin_head->ds_dir->dd_myname); 2587} 2588 2589/* 2590 * Given a pool name and a dataset object number in that pool, 2591 * return the name of that dataset. 2592 */ 2593int 2594dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2595{ 2596 dsl_pool_t *dp; 2597 dsl_dataset_t *ds; 2598 int error; 2599 2600 error = dsl_pool_hold(pname, FTAG, &dp); 2601 if (error != 0) 2602 return (error); 2603 2604 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 2605 if (error == 0) { 2606 dsl_dataset_name(ds, buf); 2607 dsl_dataset_rele(ds, FTAG); 2608 } 2609 dsl_pool_rele(dp, FTAG); 2610 2611 return (error); 2612} 2613 2614int 2615dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2616 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2617{ 2618 int error = 0; 2619 2620 ASSERT3S(asize, >, 0); 2621 2622 /* 2623 * *ref_rsrv is the portion of asize that will come from any 2624 * unconsumed refreservation space. 2625 */ 2626 *ref_rsrv = 0; 2627 2628 mutex_enter(&ds->ds_lock); 2629 /* 2630 * Make a space adjustment for reserved bytes. 2631 */ 2632 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2633 ASSERT3U(*used, >=, 2634 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2635 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2636 *ref_rsrv = 2637 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2638 } 2639 2640 if (!check_quota || ds->ds_quota == 0) { 2641 mutex_exit(&ds->ds_lock); 2642 return (0); 2643 } 2644 /* 2645 * If they are requesting more space, and our current estimate 2646 * is over quota, they get to try again unless the actual 2647 * on-disk is over quota and there are no pending changes (which 2648 * may free up space for us). 2649 */ 2650 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) { 2651 if (inflight > 0 || 2652 ds->ds_phys->ds_referenced_bytes < ds->ds_quota) 2653 error = SET_ERROR(ERESTART); 2654 else 2655 error = SET_ERROR(EDQUOT); 2656 } 2657 mutex_exit(&ds->ds_lock); 2658 2659 return (error); 2660} 2661 2662typedef struct dsl_dataset_set_qr_arg { 2663 const char *ddsqra_name; 2664 zprop_source_t ddsqra_source; 2665 uint64_t ddsqra_value; 2666} dsl_dataset_set_qr_arg_t; 2667 2668 2669/* ARGSUSED */ 2670static int 2671dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 2672{ 2673 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2674 dsl_pool_t *dp = dmu_tx_pool(tx); 2675 dsl_dataset_t *ds; 2676 int error; 2677 uint64_t newval; 2678 2679 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 2680 return (SET_ERROR(ENOTSUP)); 2681 2682 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2683 if (error != 0) 2684 return (error); 2685 2686 if (dsl_dataset_is_snapshot(ds)) { 2687 dsl_dataset_rele(ds, FTAG); 2688 return (SET_ERROR(EINVAL)); 2689 } 2690 2691 error = dsl_prop_predict(ds->ds_dir, 2692 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2693 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2694 if (error != 0) { 2695 dsl_dataset_rele(ds, FTAG); 2696 return (error); 2697 } 2698 2699 if (newval == 0) { 2700 dsl_dataset_rele(ds, FTAG); 2701 return (0); 2702 } 2703 2704 if (newval < ds->ds_phys->ds_referenced_bytes || 2705 newval < ds->ds_reserved) { 2706 dsl_dataset_rele(ds, FTAG); 2707 return (SET_ERROR(ENOSPC)); 2708 } 2709 2710 dsl_dataset_rele(ds, FTAG); 2711 return (0); 2712} 2713 2714static void 2715dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 2716{ 2717 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2718 dsl_pool_t *dp = dmu_tx_pool(tx); 2719 dsl_dataset_t *ds; 2720 uint64_t newval; 2721 2722 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2723 2724 dsl_prop_set_sync_impl(ds, 2725 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2726 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 2727 &ddsqra->ddsqra_value, tx); 2728 2729 VERIFY0(dsl_prop_get_int_ds(ds, 2730 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 2731 2732 if (ds->ds_quota != newval) { 2733 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2734 ds->ds_quota = newval; 2735 } 2736 dsl_dataset_rele(ds, FTAG); 2737} 2738 2739int 2740dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 2741 uint64_t refquota) 2742{ 2743 dsl_dataset_set_qr_arg_t ddsqra; 2744 2745 ddsqra.ddsqra_name = dsname; 2746 ddsqra.ddsqra_source = source; 2747 ddsqra.ddsqra_value = refquota; 2748 2749 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 2750 dsl_dataset_set_refquota_sync, &ddsqra, 0)); 2751} 2752 2753static int 2754dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 2755{ 2756 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2757 dsl_pool_t *dp = dmu_tx_pool(tx); 2758 dsl_dataset_t *ds; 2759 int error; 2760 uint64_t newval, unique; 2761 2762 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 2763 return (SET_ERROR(ENOTSUP)); 2764 2765 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2766 if (error != 0) 2767 return (error); 2768 2769 if (dsl_dataset_is_snapshot(ds)) { 2770 dsl_dataset_rele(ds, FTAG); 2771 return (SET_ERROR(EINVAL)); 2772 } 2773 2774 error = dsl_prop_predict(ds->ds_dir, 2775 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2776 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2777 if (error != 0) { 2778 dsl_dataset_rele(ds, FTAG); 2779 return (error); 2780 } 2781 2782 /* 2783 * If we are doing the preliminary check in open context, the 2784 * space estimates may be inaccurate. 2785 */ 2786 if (!dmu_tx_is_syncing(tx)) { 2787 dsl_dataset_rele(ds, FTAG); 2788 return (0); 2789 } 2790 2791 mutex_enter(&ds->ds_lock); 2792 if (!DS_UNIQUE_IS_ACCURATE(ds)) 2793 dsl_dataset_recalc_head_uniq(ds); 2794 unique = ds->ds_phys->ds_unique_bytes; 2795 mutex_exit(&ds->ds_lock); 2796 2797 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 2798 uint64_t delta = MAX(unique, newval) - 2799 MAX(unique, ds->ds_reserved); 2800 2801 if (delta > 2802 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 2803 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 2804 dsl_dataset_rele(ds, FTAG); 2805 return (SET_ERROR(ENOSPC)); 2806 } 2807 } 2808 2809 dsl_dataset_rele(ds, FTAG); 2810 return (0); 2811} 2812 2813void 2814dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 2815 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 2816{ 2817 uint64_t newval; 2818 uint64_t unique; 2819 int64_t delta; 2820 2821 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2822 source, sizeof (value), 1, &value, tx); 2823 2824 VERIFY0(dsl_prop_get_int_ds(ds, 2825 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 2826 2827 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2828 mutex_enter(&ds->ds_dir->dd_lock); 2829 mutex_enter(&ds->ds_lock); 2830 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 2831 unique = ds->ds_phys->ds_unique_bytes; 2832 delta = MAX(0, (int64_t)(newval - unique)) - 2833 MAX(0, (int64_t)(ds->ds_reserved - unique)); 2834 ds->ds_reserved = newval; 2835 mutex_exit(&ds->ds_lock); 2836 2837 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 2838 mutex_exit(&ds->ds_dir->dd_lock); 2839} 2840 2841static void 2842dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 2843{ 2844 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2845 dsl_pool_t *dp = dmu_tx_pool(tx); 2846 dsl_dataset_t *ds; 2847 2848 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2849 dsl_dataset_set_refreservation_sync_impl(ds, 2850 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 2851 dsl_dataset_rele(ds, FTAG); 2852} 2853 2854int 2855dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 2856 uint64_t refreservation) 2857{ 2858 dsl_dataset_set_qr_arg_t ddsqra; 2859 2860 ddsqra.ddsqra_name = dsname; 2861 ddsqra.ddsqra_source = source; 2862 ddsqra.ddsqra_value = refreservation; 2863 2864 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 2865 dsl_dataset_set_refreservation_sync, &ddsqra, 0)); 2866} 2867 2868/* 2869 * Return (in *usedp) the amount of space written in new that is not 2870 * present in oldsnap. New may be a snapshot or the head. Old must be 2871 * a snapshot before new, in new's filesystem (or its origin). If not then 2872 * fail and return EINVAL. 2873 * 2874 * The written space is calculated by considering two components: First, we 2875 * ignore any freed space, and calculate the written as new's used space 2876 * minus old's used space. Next, we add in the amount of space that was freed 2877 * between the two snapshots, thus reducing new's used space relative to old's. 2878 * Specifically, this is the space that was born before old->ds_creation_txg, 2879 * and freed before new (ie. on new's deadlist or a previous deadlist). 2880 * 2881 * space freed [---------------------] 2882 * snapshots ---O-------O--------O-------O------ 2883 * oldsnap new 2884 */ 2885int 2886dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 2887 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2888{ 2889 int err = 0; 2890 uint64_t snapobj; 2891 dsl_pool_t *dp = new->ds_dir->dd_pool; 2892 2893 ASSERT(dsl_pool_config_held(dp)); 2894 2895 *usedp = 0; 2896 *usedp += new->ds_phys->ds_referenced_bytes; 2897 *usedp -= oldsnap->ds_phys->ds_referenced_bytes; 2898 2899 *compp = 0; 2900 *compp += new->ds_phys->ds_compressed_bytes; 2901 *compp -= oldsnap->ds_phys->ds_compressed_bytes; 2902 2903 *uncompp = 0; 2904 *uncompp += new->ds_phys->ds_uncompressed_bytes; 2905 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes; 2906 2907 snapobj = new->ds_object; 2908 while (snapobj != oldsnap->ds_object) { 2909 dsl_dataset_t *snap; 2910 uint64_t used, comp, uncomp; 2911 2912 if (snapobj == new->ds_object) { 2913 snap = new; 2914 } else { 2915 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 2916 if (err != 0) 2917 break; 2918 } 2919 2920 if (snap->ds_phys->ds_prev_snap_txg == 2921 oldsnap->ds_phys->ds_creation_txg) { 2922 /* 2923 * The blocks in the deadlist can not be born after 2924 * ds_prev_snap_txg, so get the whole deadlist space, 2925 * which is more efficient (especially for old-format 2926 * deadlists). Unfortunately the deadlist code 2927 * doesn't have enough information to make this 2928 * optimization itself. 2929 */ 2930 dsl_deadlist_space(&snap->ds_deadlist, 2931 &used, &comp, &uncomp); 2932 } else { 2933 dsl_deadlist_space_range(&snap->ds_deadlist, 2934 0, oldsnap->ds_phys->ds_creation_txg, 2935 &used, &comp, &uncomp); 2936 } 2937 *usedp += used; 2938 *compp += comp; 2939 *uncompp += uncomp; 2940 2941 /* 2942 * If we get to the beginning of the chain of snapshots 2943 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 2944 * was not a snapshot of/before new. 2945 */ 2946 snapobj = snap->ds_phys->ds_prev_snap_obj; 2947 if (snap != new) 2948 dsl_dataset_rele(snap, FTAG); 2949 if (snapobj == 0) { 2950 err = SET_ERROR(EINVAL); 2951 break; 2952 } 2953 2954 } 2955 return (err); 2956} 2957 2958/* 2959 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 2960 * lastsnap, and all snapshots in between are deleted. 2961 * 2962 * blocks that would be freed [---------------------------] 2963 * snapshots ---O-------O--------O-------O--------O 2964 * firstsnap lastsnap 2965 * 2966 * This is the set of blocks that were born after the snap before firstsnap, 2967 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 2968 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 2969 * We calculate this by iterating over the relevant deadlists (from the snap 2970 * after lastsnap, backward to the snap after firstsnap), summing up the 2971 * space on the deadlist that was born after the snap before firstsnap. 2972 */ 2973int 2974dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 2975 dsl_dataset_t *lastsnap, 2976 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2977{ 2978 int err = 0; 2979 uint64_t snapobj; 2980 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 2981 2982 ASSERT(dsl_dataset_is_snapshot(firstsnap)); 2983 ASSERT(dsl_dataset_is_snapshot(lastsnap)); 2984 2985 /* 2986 * Check that the snapshots are in the same dsl_dir, and firstsnap 2987 * is before lastsnap. 2988 */ 2989 if (firstsnap->ds_dir != lastsnap->ds_dir || 2990 firstsnap->ds_phys->ds_creation_txg > 2991 lastsnap->ds_phys->ds_creation_txg) 2992 return (SET_ERROR(EINVAL)); 2993 2994 *usedp = *compp = *uncompp = 0; 2995 2996 snapobj = lastsnap->ds_phys->ds_next_snap_obj; 2997 while (snapobj != firstsnap->ds_object) { 2998 dsl_dataset_t *ds; 2999 uint64_t used, comp, uncomp; 3000 3001 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 3002 if (err != 0) 3003 break; 3004 3005 dsl_deadlist_space_range(&ds->ds_deadlist, 3006 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX, 3007 &used, &comp, &uncomp); 3008 *usedp += used; 3009 *compp += comp; 3010 *uncompp += uncomp; 3011 3012 snapobj = ds->ds_phys->ds_prev_snap_obj; 3013 ASSERT3U(snapobj, !=, 0); 3014 dsl_dataset_rele(ds, FTAG); 3015 } 3016 return (err); 3017} 3018 3019/* 3020 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 3021 * For example, they could both be snapshots of the same filesystem, and 3022 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 3023 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 3024 * filesystem. Or 'earlier' could be the origin's origin. 3025 */ 3026boolean_t 3027dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier) 3028{ 3029 dsl_pool_t *dp = later->ds_dir->dd_pool; 3030 int error; 3031 boolean_t ret; 3032 3033 ASSERT(dsl_pool_config_held(dp)); 3034 3035 if (earlier->ds_phys->ds_creation_txg >= 3036 later->ds_phys->ds_creation_txg) 3037 return (B_FALSE); 3038 3039 if (later->ds_dir == earlier->ds_dir) 3040 return (B_TRUE); 3041 if (!dsl_dir_is_clone(later->ds_dir)) 3042 return (B_FALSE); 3043 3044 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object) 3045 return (B_TRUE); 3046 dsl_dataset_t *origin; 3047 error = dsl_dataset_hold_obj(dp, 3048 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin); 3049 if (error != 0) 3050 return (B_FALSE); 3051 ret = dsl_dataset_is_before(origin, earlier); 3052 dsl_dataset_rele(origin, FTAG); 3053 return (ret); 3054} 3055