1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2013 by Delphix. All rights reserved. 24 * Copyright (c) 2012, Joyent, Inc. All rights reserved. 25 */ 26 27 #include <sys/dmu_objset.h> 28 #include <sys/dsl_dataset.h> 29 #include <sys/dsl_dir.h> 30 #include <sys/dsl_prop.h> 31 #include <sys/dsl_synctask.h> 32 #include <sys/dmu_traverse.h> 33 #include <sys/dmu_impl.h> 34 #include <sys/dmu_tx.h> 35 #include <sys/arc.h> 36 #include <sys/zio.h> 37 #include <sys/zap.h> 38 #include <sys/zfeature.h> 39 #include <sys/unique.h> 40 #include <sys/zfs_context.h> 41 #include <sys/zfs_ioctl.h> 42 #include <sys/spa.h> 43 #include <sys/zfs_znode.h> 44 #include <sys/zfs_onexit.h> 45 #include <sys/zvol.h> 46 #include <sys/dsl_scan.h> 47 #include <sys/dsl_deadlist.h> 48 #include <sys/dsl_destroy.h> 49 #include <sys/dsl_userhold.h> 50 51 #define SWITCH64(x, y) \ 52 { \ 53 uint64_t __tmp = (x); \ 54 (x) = (y); \ 55 (y) = __tmp; \ 56 } 57 58 #define DS_REF_MAX (1ULL << 62) 59 60 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 61 62 /* 63 * Figure out how much of this delta should be propogated to the dsl_dir 64 * layer. If there's a refreservation, that space has already been 65 * partially accounted for in our ancestors. 66 */ 67 static int64_t 68 parent_delta(dsl_dataset_t *ds, int64_t delta) 69 { 70 uint64_t old_bytes, new_bytes; 71 72 if (ds->ds_reserved == 0) 73 return (delta); 74 75 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 76 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 77 78 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 79 return (new_bytes - old_bytes); 80 } 81 82 void 83 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 84 { 85 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 86 int compressed = BP_GET_PSIZE(bp); 87 int uncompressed = BP_GET_UCSIZE(bp); 88 int64_t delta; 89 90 dprintf_bp(bp, "ds=%p", ds); 91 92 ASSERT(dmu_tx_is_syncing(tx)); 93 /* It could have been compressed away to nothing */ 94 if (BP_IS_HOLE(bp)) 95 return; 96 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 97 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 98 if (ds == NULL) { 99 dsl_pool_mos_diduse_space(tx->tx_pool, 100 used, compressed, uncompressed); 101 return; 102 } 103 dmu_buf_will_dirty(ds->ds_dbuf, tx); 104 105 mutex_enter(&ds->ds_dir->dd_lock); 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 mutex_exit(&ds->ds_dir->dd_lock); 118 } 119 120 int 121 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 122 boolean_t async) 123 { 124 if (BP_IS_HOLE(bp)) 125 return (0); 126 127 ASSERT(dmu_tx_is_syncing(tx)); 128 ASSERT(bp->blk_birth <= tx->tx_txg); 129 130 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 131 int compressed = BP_GET_PSIZE(bp); 132 int uncompressed = BP_GET_UCSIZE(bp); 133 134 ASSERT(used > 0); 135 if (ds == NULL) { 136 dsl_free(tx->tx_pool, tx->tx_txg, bp); 137 dsl_pool_mos_diduse_space(tx->tx_pool, 138 -used, -compressed, -uncompressed); 139 return (used); 140 } 141 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 142 143 ASSERT(!dsl_dataset_is_snapshot(ds)); 144 dmu_buf_will_dirty(ds->ds_dbuf, tx); 145 146 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) { 147 int64_t delta; 148 149 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 150 dsl_free(tx->tx_pool, tx->tx_txg, bp); 151 152 mutex_enter(&ds->ds_dir->dd_lock); 153 mutex_enter(&ds->ds_lock); 154 ASSERT(ds->ds_phys->ds_unique_bytes >= used || 155 !DS_UNIQUE_IS_ACCURATE(ds)); 156 delta = parent_delta(ds, -used); 157 ds->ds_phys->ds_unique_bytes -= used; 158 mutex_exit(&ds->ds_lock); 159 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 160 delta, -compressed, -uncompressed, tx); 161 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 162 DD_USED_REFRSRV, DD_USED_HEAD, tx); 163 mutex_exit(&ds->ds_dir->dd_lock); 164 } else { 165 dprintf_bp(bp, "putting on dead list: %s", ""); 166 if (async) { 167 /* 168 * We are here as part of zio's write done callback, 169 * which means we're a zio interrupt thread. We can't 170 * call dsl_deadlist_insert() now because it may block 171 * waiting for I/O. Instead, put bp on the deferred 172 * queue and let dsl_pool_sync() finish the job. 173 */ 174 bplist_append(&ds->ds_pending_deadlist, bp); 175 } else { 176 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 177 } 178 ASSERT3U(ds->ds_prev->ds_object, ==, 179 ds->ds_phys->ds_prev_snap_obj); 180 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0); 181 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 182 if (ds->ds_prev->ds_phys->ds_next_snap_obj == 183 ds->ds_object && bp->blk_birth > 184 ds->ds_prev->ds_phys->ds_prev_snap_txg) { 185 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 186 mutex_enter(&ds->ds_prev->ds_lock); 187 ds->ds_prev->ds_phys->ds_unique_bytes += used; 188 mutex_exit(&ds->ds_prev->ds_lock); 189 } 190 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 191 dsl_dir_transfer_space(ds->ds_dir, used, 192 DD_USED_HEAD, DD_USED_SNAP, tx); 193 } 194 } 195 mutex_enter(&ds->ds_lock); 196 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used); 197 ds->ds_phys->ds_referenced_bytes -= used; 198 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed); 199 ds->ds_phys->ds_compressed_bytes -= compressed; 200 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed); 201 ds->ds_phys->ds_uncompressed_bytes -= uncompressed; 202 mutex_exit(&ds->ds_lock); 203 204 return (used); 205 } 206 207 uint64_t 208 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 209 { 210 uint64_t trysnap = 0; 211 212 if (ds == NULL) 213 return (0); 214 /* 215 * The snapshot creation could fail, but that would cause an 216 * incorrect FALSE return, which would only result in an 217 * overestimation of the amount of space that an operation would 218 * consume, which is OK. 219 * 220 * There's also a small window where we could miss a pending 221 * snapshot, because we could set the sync task in the quiescing 222 * phase. So this should only be used as a guess. 223 */ 224 if (ds->ds_trysnap_txg > 225 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 226 trysnap = ds->ds_trysnap_txg; 227 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap)); 228 } 229 230 boolean_t 231 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp, 232 uint64_t blk_birth) 233 { 234 if (blk_birth <= dsl_dataset_prev_snap_txg(ds)) 235 return (B_FALSE); 236 237 ddt_prefetch(dsl_dataset_get_spa(ds), bp); 238 239 return (B_TRUE); 240 } 241 242 /* ARGSUSED */ 243 static void 244 dsl_dataset_evict(dmu_buf_t *db, void *dsv) 245 { 246 dsl_dataset_t *ds = dsv; 247 248 ASSERT(ds->ds_owner == NULL); 249 250 unique_remove(ds->ds_fsid_guid); 251 252 if (ds->ds_objset != NULL) 253 dmu_objset_evict(ds->ds_objset); 254 255 if (ds->ds_prev) { 256 dsl_dataset_rele(ds->ds_prev, ds); 257 ds->ds_prev = NULL; 258 } 259 260 bplist_destroy(&ds->ds_pending_deadlist); 261 if (ds->ds_phys->ds_deadlist_obj != 0) 262 dsl_deadlist_close(&ds->ds_deadlist); 263 if (ds->ds_dir) 264 dsl_dir_rele(ds->ds_dir, ds); 265 266 ASSERT(!list_link_active(&ds->ds_synced_link)); 267 268 mutex_destroy(&ds->ds_lock); 269 mutex_destroy(&ds->ds_opening_lock); 270 refcount_destroy(&ds->ds_longholds); 271 272 kmem_free(ds, sizeof (dsl_dataset_t)); 273 } 274 275 int 276 dsl_dataset_get_snapname(dsl_dataset_t *ds) 277 { 278 dsl_dataset_phys_t *headphys; 279 int err; 280 dmu_buf_t *headdbuf; 281 dsl_pool_t *dp = ds->ds_dir->dd_pool; 282 objset_t *mos = dp->dp_meta_objset; 283 284 if (ds->ds_snapname[0]) 285 return (0); 286 if (ds->ds_phys->ds_next_snap_obj == 0) 287 return (0); 288 289 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 290 FTAG, &headdbuf); 291 if (err != 0) 292 return (err); 293 headphys = headdbuf->db_data; 294 err = zap_value_search(dp->dp_meta_objset, 295 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 296 dmu_buf_rele(headdbuf, FTAG); 297 return (err); 298 } 299 300 int 301 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 302 { 303 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 304 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 305 matchtype_t mt; 306 int err; 307 308 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 309 mt = MT_FIRST; 310 else 311 mt = MT_EXACT; 312 313 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 314 value, mt, NULL, 0, NULL); 315 if (err == ENOTSUP && mt == MT_FIRST) 316 err = zap_lookup(mos, snapobj, name, 8, 1, value); 317 return (err); 318 } 319 320 int 321 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx) 322 { 323 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 324 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 325 matchtype_t mt; 326 int err; 327 328 dsl_dir_snap_cmtime_update(ds->ds_dir); 329 330 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 331 mt = MT_FIRST; 332 else 333 mt = MT_EXACT; 334 335 err = zap_remove_norm(mos, snapobj, name, mt, tx); 336 if (err == ENOTSUP && mt == MT_FIRST) 337 err = zap_remove(mos, snapobj, name, tx); 338 return (err); 339 } 340 341 int 342 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 343 dsl_dataset_t **dsp) 344 { 345 objset_t *mos = dp->dp_meta_objset; 346 dmu_buf_t *dbuf; 347 dsl_dataset_t *ds; 348 int err; 349 dmu_object_info_t doi; 350 351 ASSERT(dsl_pool_config_held(dp)); 352 353 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 354 if (err != 0) 355 return (err); 356 357 /* Make sure dsobj has the correct object type. */ 358 dmu_object_info_from_db(dbuf, &doi); 359 if (doi.doi_type != DMU_OT_DSL_DATASET) { 360 dmu_buf_rele(dbuf, tag); 361 return (SET_ERROR(EINVAL)); 362 } 363 364 ds = dmu_buf_get_user(dbuf); 365 if (ds == NULL) { 366 dsl_dataset_t *winner = NULL; 367 368 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 369 ds->ds_dbuf = dbuf; 370 ds->ds_object = dsobj; 371 ds->ds_phys = dbuf->db_data; 372 373 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 374 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 375 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 376 refcount_create(&ds->ds_longholds); 377 378 bplist_create(&ds->ds_pending_deadlist); 379 dsl_deadlist_open(&ds->ds_deadlist, 380 mos, ds->ds_phys->ds_deadlist_obj); 381 382 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 383 offsetof(dmu_sendarg_t, dsa_link)); 384 385 if (err == 0) { 386 err = dsl_dir_hold_obj(dp, 387 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 388 } 389 if (err != 0) { 390 mutex_destroy(&ds->ds_lock); 391 mutex_destroy(&ds->ds_opening_lock); 392 refcount_destroy(&ds->ds_longholds); 393 bplist_destroy(&ds->ds_pending_deadlist); 394 dsl_deadlist_close(&ds->ds_deadlist); 395 kmem_free(ds, sizeof (dsl_dataset_t)); 396 dmu_buf_rele(dbuf, tag); 397 return (err); 398 } 399 400 if (!dsl_dataset_is_snapshot(ds)) { 401 ds->ds_snapname[0] = '\0'; 402 if (ds->ds_phys->ds_prev_snap_obj != 0) { 403 err = dsl_dataset_hold_obj(dp, 404 ds->ds_phys->ds_prev_snap_obj, 405 ds, &ds->ds_prev); 406 } 407 } else { 408 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 409 err = dsl_dataset_get_snapname(ds); 410 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) { 411 err = zap_count( 412 ds->ds_dir->dd_pool->dp_meta_objset, 413 ds->ds_phys->ds_userrefs_obj, 414 &ds->ds_userrefs); 415 } 416 } 417 418 if (err == 0 && !dsl_dataset_is_snapshot(ds)) { 419 err = dsl_prop_get_int_ds(ds, 420 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 421 &ds->ds_reserved); 422 if (err == 0) { 423 err = dsl_prop_get_int_ds(ds, 424 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 425 &ds->ds_quota); 426 } 427 } else { 428 ds->ds_reserved = ds->ds_quota = 0; 429 } 430 431 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds, 432 &ds->ds_phys, dsl_dataset_evict)) != NULL) { 433 bplist_destroy(&ds->ds_pending_deadlist); 434 dsl_deadlist_close(&ds->ds_deadlist); 435 if (ds->ds_prev) 436 dsl_dataset_rele(ds->ds_prev, ds); 437 dsl_dir_rele(ds->ds_dir, ds); 438 mutex_destroy(&ds->ds_lock); 439 mutex_destroy(&ds->ds_opening_lock); 440 refcount_destroy(&ds->ds_longholds); 441 kmem_free(ds, sizeof (dsl_dataset_t)); 442 if (err != 0) { 443 dmu_buf_rele(dbuf, tag); 444 return (err); 445 } 446 ds = winner; 447 } else { 448 ds->ds_fsid_guid = 449 unique_insert(ds->ds_phys->ds_fsid_guid); 450 } 451 } 452 ASSERT3P(ds->ds_dbuf, ==, dbuf); 453 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 454 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 || 455 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 456 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 457 *dsp = ds; 458 return (0); 459 } 460 461 int 462 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 463 void *tag, dsl_dataset_t **dsp) 464 { 465 dsl_dir_t *dd; 466 const char *snapname; 467 uint64_t obj; 468 int err = 0; 469 470 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 471 if (err != 0) 472 return (err); 473 474 ASSERT(dsl_pool_config_held(dp)); 475 obj = dd->dd_phys->dd_head_dataset_obj; 476 if (obj != 0) 477 err = dsl_dataset_hold_obj(dp, obj, tag, dsp); 478 else 479 err = SET_ERROR(ENOENT); 480 481 /* we may be looking for a snapshot */ 482 if (err == 0 && snapname != NULL) { 483 dsl_dataset_t *ds; 484 485 if (*snapname++ != '@') { 486 dsl_dataset_rele(*dsp, tag); 487 dsl_dir_rele(dd, FTAG); 488 return (SET_ERROR(ENOENT)); 489 } 490 491 dprintf("looking for snapshot '%s'\n", snapname); 492 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 493 if (err == 0) 494 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 495 dsl_dataset_rele(*dsp, tag); 496 497 if (err == 0) { 498 mutex_enter(&ds->ds_lock); 499 if (ds->ds_snapname[0] == 0) 500 (void) strlcpy(ds->ds_snapname, snapname, 501 sizeof (ds->ds_snapname)); 502 mutex_exit(&ds->ds_lock); 503 *dsp = ds; 504 } 505 } 506 507 dsl_dir_rele(dd, FTAG); 508 return (err); 509 } 510 511 int 512 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 513 void *tag, dsl_dataset_t **dsp) 514 { 515 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 516 if (err != 0) 517 return (err); 518 if (!dsl_dataset_tryown(*dsp, tag)) { 519 dsl_dataset_rele(*dsp, tag); 520 *dsp = NULL; 521 return (SET_ERROR(EBUSY)); 522 } 523 return (0); 524 } 525 526 int 527 dsl_dataset_own(dsl_pool_t *dp, const char *name, 528 void *tag, dsl_dataset_t **dsp) 529 { 530 int err = dsl_dataset_hold(dp, name, tag, dsp); 531 if (err != 0) 532 return (err); 533 if (!dsl_dataset_tryown(*dsp, tag)) { 534 dsl_dataset_rele(*dsp, tag); 535 return (SET_ERROR(EBUSY)); 536 } 537 return (0); 538 } 539 540 /* 541 * See the comment above dsl_pool_hold() for details. In summary, a long 542 * hold is used to prevent destruction of a dataset while the pool hold 543 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 544 * 545 * The dataset and pool must be held when this function is called. After it 546 * is called, the pool hold may be released while the dataset is still held 547 * and accessed. 548 */ 549 void 550 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 551 { 552 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 553 (void) refcount_add(&ds->ds_longholds, tag); 554 } 555 556 void 557 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 558 { 559 (void) refcount_remove(&ds->ds_longholds, tag); 560 } 561 562 /* Return B_TRUE if there are any long holds on this dataset. */ 563 boolean_t 564 dsl_dataset_long_held(dsl_dataset_t *ds) 565 { 566 return (!refcount_is_zero(&ds->ds_longholds)); 567 } 568 569 void 570 dsl_dataset_name(dsl_dataset_t *ds, char *name) 571 { 572 if (ds == NULL) { 573 (void) strcpy(name, "mos"); 574 } else { 575 dsl_dir_name(ds->ds_dir, name); 576 VERIFY0(dsl_dataset_get_snapname(ds)); 577 if (ds->ds_snapname[0]) { 578 (void) strcat(name, "@"); 579 /* 580 * We use a "recursive" mutex so that we 581 * can call dprintf_ds() with ds_lock held. 582 */ 583 if (!MUTEX_HELD(&ds->ds_lock)) { 584 mutex_enter(&ds->ds_lock); 585 (void) strcat(name, ds->ds_snapname); 586 mutex_exit(&ds->ds_lock); 587 } else { 588 (void) strcat(name, ds->ds_snapname); 589 } 590 } 591 } 592 } 593 594 static int 595 dsl_dataset_namelen(dsl_dataset_t *ds) 596 { 597 int result; 598 599 if (ds == NULL) { 600 result = 3; /* "mos" */ 601 } else { 602 result = dsl_dir_namelen(ds->ds_dir); 603 VERIFY0(dsl_dataset_get_snapname(ds)); 604 if (ds->ds_snapname[0]) { 605 ++result; /* adding one for the @-sign */ 606 if (!MUTEX_HELD(&ds->ds_lock)) { 607 mutex_enter(&ds->ds_lock); 608 result += strlen(ds->ds_snapname); 609 mutex_exit(&ds->ds_lock); 610 } else { 611 result += strlen(ds->ds_snapname); 612 } 613 } 614 } 615 616 return (result); 617 } 618 619 void 620 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 621 { 622 dmu_buf_rele(ds->ds_dbuf, tag); 623 } 624 625 void 626 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 627 { 628 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL); 629 630 mutex_enter(&ds->ds_lock); 631 ds->ds_owner = NULL; 632 mutex_exit(&ds->ds_lock); 633 dsl_dataset_long_rele(ds, tag); 634 if (ds->ds_dbuf != NULL) 635 dsl_dataset_rele(ds, tag); 636 else 637 dsl_dataset_evict(NULL, ds); 638 } 639 640 boolean_t 641 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 642 { 643 boolean_t gotit = FALSE; 644 645 mutex_enter(&ds->ds_lock); 646 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 647 ds->ds_owner = tag; 648 dsl_dataset_long_hold(ds, tag); 649 gotit = TRUE; 650 } 651 mutex_exit(&ds->ds_lock); 652 return (gotit); 653 } 654 655 uint64_t 656 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 657 uint64_t flags, dmu_tx_t *tx) 658 { 659 dsl_pool_t *dp = dd->dd_pool; 660 dmu_buf_t *dbuf; 661 dsl_dataset_phys_t *dsphys; 662 uint64_t dsobj; 663 objset_t *mos = dp->dp_meta_objset; 664 665 if (origin == NULL) 666 origin = dp->dp_origin_snap; 667 668 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 669 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 670 ASSERT(dmu_tx_is_syncing(tx)); 671 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 672 673 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 674 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 675 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 676 dmu_buf_will_dirty(dbuf, tx); 677 dsphys = dbuf->db_data; 678 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 679 dsphys->ds_dir_obj = dd->dd_object; 680 dsphys->ds_flags = flags; 681 dsphys->ds_fsid_guid = unique_create(); 682 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 683 sizeof (dsphys->ds_guid)); 684 dsphys->ds_snapnames_zapobj = 685 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 686 DMU_OT_NONE, 0, tx); 687 dsphys->ds_creation_time = gethrestime_sec(); 688 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 689 690 if (origin == NULL) { 691 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 692 } else { 693 dsl_dataset_t *ohds; /* head of the origin snapshot */ 694 695 dsphys->ds_prev_snap_obj = origin->ds_object; 696 dsphys->ds_prev_snap_txg = 697 origin->ds_phys->ds_creation_txg; 698 dsphys->ds_referenced_bytes = 699 origin->ds_phys->ds_referenced_bytes; 700 dsphys->ds_compressed_bytes = 701 origin->ds_phys->ds_compressed_bytes; 702 dsphys->ds_uncompressed_bytes = 703 origin->ds_phys->ds_uncompressed_bytes; 704 dsphys->ds_bp = origin->ds_phys->ds_bp; 705 dsphys->ds_flags |= origin->ds_phys->ds_flags; 706 707 dmu_buf_will_dirty(origin->ds_dbuf, tx); 708 origin->ds_phys->ds_num_children++; 709 710 VERIFY0(dsl_dataset_hold_obj(dp, 711 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds)); 712 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 713 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 714 dsl_dataset_rele(ohds, FTAG); 715 716 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 717 if (origin->ds_phys->ds_next_clones_obj == 0) { 718 origin->ds_phys->ds_next_clones_obj = 719 zap_create(mos, 720 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 721 } 722 VERIFY0(zap_add_int(mos, 723 origin->ds_phys->ds_next_clones_obj, dsobj, tx)); 724 } 725 726 dmu_buf_will_dirty(dd->dd_dbuf, tx); 727 dd->dd_phys->dd_origin_obj = origin->ds_object; 728 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 729 if (origin->ds_dir->dd_phys->dd_clones == 0) { 730 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 731 origin->ds_dir->dd_phys->dd_clones = 732 zap_create(mos, 733 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 734 } 735 VERIFY0(zap_add_int(mos, 736 origin->ds_dir->dd_phys->dd_clones, dsobj, tx)); 737 } 738 } 739 740 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 741 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 742 743 dmu_buf_rele(dbuf, FTAG); 744 745 dmu_buf_will_dirty(dd->dd_dbuf, tx); 746 dd->dd_phys->dd_head_dataset_obj = dsobj; 747 748 return (dsobj); 749 } 750 751 static void 752 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 753 { 754 objset_t *os; 755 756 VERIFY0(dmu_objset_from_ds(ds, &os)); 757 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 758 dsl_dataset_dirty(ds, tx); 759 } 760 761 uint64_t 762 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 763 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 764 { 765 dsl_pool_t *dp = pdd->dd_pool; 766 uint64_t dsobj, ddobj; 767 dsl_dir_t *dd; 768 769 ASSERT(dmu_tx_is_syncing(tx)); 770 ASSERT(lastname[0] != '@'); 771 772 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 773 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 774 775 dsobj = dsl_dataset_create_sync_dd(dd, origin, 776 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 777 778 dsl_deleg_set_create_perms(dd, tx, cr); 779 780 dsl_dir_rele(dd, FTAG); 781 782 /* 783 * If we are creating a clone, make sure we zero out any stale 784 * data from the origin snapshots zil header. 785 */ 786 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 787 dsl_dataset_t *ds; 788 789 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 790 dsl_dataset_zero_zil(ds, tx); 791 dsl_dataset_rele(ds, FTAG); 792 } 793 794 return (dsobj); 795 } 796 797 /* 798 * The unique space in the head dataset can be calculated by subtracting 799 * the space used in the most recent snapshot, that is still being used 800 * in this file system, from the space currently in use. To figure out 801 * the space in the most recent snapshot still in use, we need to take 802 * the total space used in the snapshot and subtract out the space that 803 * has been freed up since the snapshot was taken. 804 */ 805 void 806 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 807 { 808 uint64_t mrs_used; 809 uint64_t dlused, dlcomp, dluncomp; 810 811 ASSERT(!dsl_dataset_is_snapshot(ds)); 812 813 if (ds->ds_phys->ds_prev_snap_obj != 0) 814 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes; 815 else 816 mrs_used = 0; 817 818 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 819 820 ASSERT3U(dlused, <=, mrs_used); 821 ds->ds_phys->ds_unique_bytes = 822 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused); 823 824 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 825 SPA_VERSION_UNIQUE_ACCURATE) 826 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 827 } 828 829 void 830 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 831 dmu_tx_t *tx) 832 { 833 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 834 uint64_t count; 835 int err; 836 837 ASSERT(ds->ds_phys->ds_num_children >= 2); 838 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx); 839 /* 840 * The err should not be ENOENT, but a bug in a previous version 841 * of the code could cause upgrade_clones_cb() to not set 842 * ds_next_snap_obj when it should, leading to a missing entry. 843 * If we knew that the pool was created after 844 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 845 * ENOENT. However, at least we can check that we don't have 846 * too many entries in the next_clones_obj even after failing to 847 * remove this one. 848 */ 849 if (err != ENOENT) 850 VERIFY0(err); 851 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 852 &count)); 853 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2); 854 } 855 856 857 blkptr_t * 858 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 859 { 860 return (&ds->ds_phys->ds_bp); 861 } 862 863 void 864 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 865 { 866 ASSERT(dmu_tx_is_syncing(tx)); 867 /* If it's the meta-objset, set dp_meta_rootbp */ 868 if (ds == NULL) { 869 tx->tx_pool->dp_meta_rootbp = *bp; 870 } else { 871 dmu_buf_will_dirty(ds->ds_dbuf, tx); 872 ds->ds_phys->ds_bp = *bp; 873 } 874 } 875 876 spa_t * 877 dsl_dataset_get_spa(dsl_dataset_t *ds) 878 { 879 return (ds->ds_dir->dd_pool->dp_spa); 880 } 881 882 void 883 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 884 { 885 dsl_pool_t *dp; 886 887 if (ds == NULL) /* this is the meta-objset */ 888 return; 889 890 ASSERT(ds->ds_objset != NULL); 891 892 if (ds->ds_phys->ds_next_snap_obj != 0) 893 panic("dirtying snapshot!"); 894 895 dp = ds->ds_dir->dd_pool; 896 897 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 898 /* up the hold count until we can be written out */ 899 dmu_buf_add_ref(ds->ds_dbuf, ds); 900 } 901 } 902 903 boolean_t 904 dsl_dataset_is_dirty(dsl_dataset_t *ds) 905 { 906 for (int t = 0; t < TXG_SIZE; t++) { 907 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 908 ds, t)) 909 return (B_TRUE); 910 } 911 return (B_FALSE); 912 } 913 914 static int 915 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 916 { 917 uint64_t asize; 918 919 if (!dmu_tx_is_syncing(tx)) 920 return (0); 921 922 /* 923 * If there's an fs-only reservation, any blocks that might become 924 * owned by the snapshot dataset must be accommodated by space 925 * outside of the reservation. 926 */ 927 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 928 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 929 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 930 return (SET_ERROR(ENOSPC)); 931 932 /* 933 * Propagate any reserved space for this snapshot to other 934 * snapshot checks in this sync group. 935 */ 936 if (asize > 0) 937 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 938 939 return (0); 940 } 941 942 typedef struct dsl_dataset_snapshot_arg { 943 nvlist_t *ddsa_snaps; 944 nvlist_t *ddsa_props; 945 nvlist_t *ddsa_errors; 946 } dsl_dataset_snapshot_arg_t; 947 948 int 949 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 950 dmu_tx_t *tx) 951 { 952 int error; 953 uint64_t value; 954 955 ds->ds_trysnap_txg = tx->tx_txg; 956 957 if (!dmu_tx_is_syncing(tx)) 958 return (0); 959 960 /* 961 * We don't allow multiple snapshots of the same txg. If there 962 * is already one, try again. 963 */ 964 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 965 return (SET_ERROR(EAGAIN)); 966 967 /* 968 * Check for conflicting snapshot name. 969 */ 970 error = dsl_dataset_snap_lookup(ds, snapname, &value); 971 if (error == 0) 972 return (SET_ERROR(EEXIST)); 973 if (error != ENOENT) 974 return (error); 975 976 error = dsl_dataset_snapshot_reserve_space(ds, tx); 977 if (error != 0) 978 return (error); 979 980 return (0); 981 } 982 983 static int 984 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 985 { 986 dsl_dataset_snapshot_arg_t *ddsa = arg; 987 dsl_pool_t *dp = dmu_tx_pool(tx); 988 nvpair_t *pair; 989 int rv = 0; 990 991 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 992 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 993 int error = 0; 994 dsl_dataset_t *ds; 995 char *name, *atp; 996 char dsname[MAXNAMELEN]; 997 998 name = nvpair_name(pair); 999 if (strlen(name) >= MAXNAMELEN) 1000 error = SET_ERROR(ENAMETOOLONG); 1001 if (error == 0) { 1002 atp = strchr(name, '@'); 1003 if (atp == NULL) 1004 error = SET_ERROR(EINVAL); 1005 if (error == 0) 1006 (void) strlcpy(dsname, name, atp - name + 1); 1007 } 1008 if (error == 0) 1009 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1010 if (error == 0) { 1011 error = dsl_dataset_snapshot_check_impl(ds, 1012 atp + 1, tx); 1013 dsl_dataset_rele(ds, FTAG); 1014 } 1015 1016 if (error != 0) { 1017 if (ddsa->ddsa_errors != NULL) { 1018 fnvlist_add_int32(ddsa->ddsa_errors, 1019 name, error); 1020 } 1021 rv = error; 1022 } 1023 } 1024 return (rv); 1025 } 1026 1027 void 1028 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1029 dmu_tx_t *tx) 1030 { 1031 static zil_header_t zero_zil; 1032 1033 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1034 dmu_buf_t *dbuf; 1035 dsl_dataset_phys_t *dsphys; 1036 uint64_t dsobj, crtxg; 1037 objset_t *mos = dp->dp_meta_objset; 1038 objset_t *os; 1039 1040 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1041 1042 /* 1043 * If we are on an old pool, the zil must not be active, in which 1044 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1045 */ 1046 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1047 dmu_objset_from_ds(ds, &os) != 0 || 1048 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1049 sizeof (zero_zil)) == 0); 1050 1051 1052 /* 1053 * The origin's ds_creation_txg has to be < TXG_INITIAL 1054 */ 1055 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1056 crtxg = 1; 1057 else 1058 crtxg = tx->tx_txg; 1059 1060 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1061 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1062 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1063 dmu_buf_will_dirty(dbuf, tx); 1064 dsphys = dbuf->db_data; 1065 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1066 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1067 dsphys->ds_fsid_guid = unique_create(); 1068 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1069 sizeof (dsphys->ds_guid)); 1070 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1071 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1072 dsphys->ds_next_snap_obj = ds->ds_object; 1073 dsphys->ds_num_children = 1; 1074 dsphys->ds_creation_time = gethrestime_sec(); 1075 dsphys->ds_creation_txg = crtxg; 1076 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1077 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes; 1078 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1079 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1080 dsphys->ds_flags = ds->ds_phys->ds_flags; 1081 dsphys->ds_bp = ds->ds_phys->ds_bp; 1082 dmu_buf_rele(dbuf, FTAG); 1083 1084 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1085 if (ds->ds_prev) { 1086 uint64_t next_clones_obj = 1087 ds->ds_prev->ds_phys->ds_next_clones_obj; 1088 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1089 ds->ds_object || 1090 ds->ds_prev->ds_phys->ds_num_children > 1); 1091 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1092 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1093 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1094 ds->ds_prev->ds_phys->ds_creation_txg); 1095 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1096 } else if (next_clones_obj != 0) { 1097 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1098 dsphys->ds_next_snap_obj, tx); 1099 VERIFY0(zap_add_int(mos, 1100 next_clones_obj, dsobj, tx)); 1101 } 1102 } 1103 1104 /* 1105 * If we have a reference-reservation on this dataset, we will 1106 * need to increase the amount of refreservation being charged 1107 * since our unique space is going to zero. 1108 */ 1109 if (ds->ds_reserved) { 1110 int64_t delta; 1111 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1112 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 1113 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1114 delta, 0, 0, tx); 1115 } 1116 1117 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1118 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist, 1119 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx); 1120 dsl_deadlist_close(&ds->ds_deadlist); 1121 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj); 1122 dsl_deadlist_add_key(&ds->ds_deadlist, 1123 ds->ds_phys->ds_prev_snap_txg, tx); 1124 1125 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1126 ds->ds_phys->ds_prev_snap_obj = dsobj; 1127 ds->ds_phys->ds_prev_snap_txg = crtxg; 1128 ds->ds_phys->ds_unique_bytes = 0; 1129 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1130 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1131 1132 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1133 snapname, 8, 1, &dsobj, tx)); 1134 1135 if (ds->ds_prev) 1136 dsl_dataset_rele(ds->ds_prev, ds); 1137 VERIFY0(dsl_dataset_hold_obj(dp, 1138 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1139 1140 dsl_scan_ds_snapshotted(ds, tx); 1141 1142 dsl_dir_snap_cmtime_update(ds->ds_dir); 1143 1144 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1145 } 1146 1147 static void 1148 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1149 { 1150 dsl_dataset_snapshot_arg_t *ddsa = arg; 1151 dsl_pool_t *dp = dmu_tx_pool(tx); 1152 nvpair_t *pair; 1153 1154 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1155 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1156 dsl_dataset_t *ds; 1157 char *name, *atp; 1158 char dsname[MAXNAMELEN]; 1159 1160 name = nvpair_name(pair); 1161 atp = strchr(name, '@'); 1162 (void) strlcpy(dsname, name, atp - name + 1); 1163 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1164 1165 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1166 if (ddsa->ddsa_props != NULL) { 1167 dsl_props_set_sync_impl(ds->ds_prev, 1168 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1169 } 1170 dsl_dataset_rele(ds, FTAG); 1171 } 1172 } 1173 1174 /* 1175 * The snapshots must all be in the same pool. 1176 * All-or-nothing: if there are any failures, nothing will be modified. 1177 */ 1178 int 1179 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1180 { 1181 dsl_dataset_snapshot_arg_t ddsa; 1182 nvpair_t *pair; 1183 boolean_t needsuspend; 1184 int error; 1185 spa_t *spa; 1186 char *firstname; 1187 nvlist_t *suspended = NULL; 1188 1189 pair = nvlist_next_nvpair(snaps, NULL); 1190 if (pair == NULL) 1191 return (0); 1192 firstname = nvpair_name(pair); 1193 1194 error = spa_open(firstname, &spa, FTAG); 1195 if (error != 0) 1196 return (error); 1197 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1198 spa_close(spa, FTAG); 1199 1200 if (needsuspend) { 1201 suspended = fnvlist_alloc(); 1202 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1203 pair = nvlist_next_nvpair(snaps, pair)) { 1204 char fsname[MAXNAMELEN]; 1205 char *snapname = nvpair_name(pair); 1206 char *atp; 1207 void *cookie; 1208 1209 atp = strchr(snapname, '@'); 1210 if (atp == NULL) { 1211 error = SET_ERROR(EINVAL); 1212 break; 1213 } 1214 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1215 1216 error = zil_suspend(fsname, &cookie); 1217 if (error != 0) 1218 break; 1219 fnvlist_add_uint64(suspended, fsname, 1220 (uintptr_t)cookie); 1221 } 1222 } 1223 1224 ddsa.ddsa_snaps = snaps; 1225 ddsa.ddsa_props = props; 1226 ddsa.ddsa_errors = errors; 1227 1228 if (error == 0) { 1229 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1230 dsl_dataset_snapshot_sync, &ddsa, 1231 fnvlist_num_pairs(snaps) * 3); 1232 } 1233 1234 if (suspended != NULL) { 1235 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1236 pair = nvlist_next_nvpair(suspended, pair)) { 1237 zil_resume((void *)(uintptr_t) 1238 fnvpair_value_uint64(pair)); 1239 } 1240 fnvlist_free(suspended); 1241 } 1242 1243 return (error); 1244 } 1245 1246 typedef struct dsl_dataset_snapshot_tmp_arg { 1247 const char *ddsta_fsname; 1248 const char *ddsta_snapname; 1249 minor_t ddsta_cleanup_minor; 1250 const char *ddsta_htag; 1251 } dsl_dataset_snapshot_tmp_arg_t; 1252 1253 static int 1254 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1255 { 1256 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1257 dsl_pool_t *dp = dmu_tx_pool(tx); 1258 dsl_dataset_t *ds; 1259 int error; 1260 1261 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1262 if (error != 0) 1263 return (error); 1264 1265 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, tx); 1266 if (error != 0) { 1267 dsl_dataset_rele(ds, FTAG); 1268 return (error); 1269 } 1270 1271 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1272 dsl_dataset_rele(ds, FTAG); 1273 return (SET_ERROR(ENOTSUP)); 1274 } 1275 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1276 B_TRUE, tx); 1277 if (error != 0) { 1278 dsl_dataset_rele(ds, FTAG); 1279 return (error); 1280 } 1281 1282 dsl_dataset_rele(ds, FTAG); 1283 return (0); 1284 } 1285 1286 static void 1287 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1288 { 1289 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1290 dsl_pool_t *dp = dmu_tx_pool(tx); 1291 dsl_dataset_t *ds; 1292 1293 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1294 1295 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1296 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1297 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1298 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1299 1300 dsl_dataset_rele(ds, FTAG); 1301 } 1302 1303 int 1304 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1305 minor_t cleanup_minor, const char *htag) 1306 { 1307 dsl_dataset_snapshot_tmp_arg_t ddsta; 1308 int error; 1309 spa_t *spa; 1310 boolean_t needsuspend; 1311 void *cookie; 1312 1313 ddsta.ddsta_fsname = fsname; 1314 ddsta.ddsta_snapname = snapname; 1315 ddsta.ddsta_cleanup_minor = cleanup_minor; 1316 ddsta.ddsta_htag = htag; 1317 1318 error = spa_open(fsname, &spa, FTAG); 1319 if (error != 0) 1320 return (error); 1321 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1322 spa_close(spa, FTAG); 1323 1324 if (needsuspend) { 1325 error = zil_suspend(fsname, &cookie); 1326 if (error != 0) 1327 return (error); 1328 } 1329 1330 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1331 dsl_dataset_snapshot_tmp_sync, &ddsta, 3); 1332 1333 if (needsuspend) 1334 zil_resume(cookie); 1335 return (error); 1336 } 1337 1338 1339 void 1340 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1341 { 1342 ASSERT(dmu_tx_is_syncing(tx)); 1343 ASSERT(ds->ds_objset != NULL); 1344 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1345 1346 /* 1347 * in case we had to change ds_fsid_guid when we opened it, 1348 * sync it out now. 1349 */ 1350 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1351 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1352 1353 dmu_objset_sync(ds->ds_objset, zio, tx); 1354 } 1355 1356 static void 1357 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1358 { 1359 uint64_t count = 0; 1360 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1361 zap_cursor_t zc; 1362 zap_attribute_t za; 1363 nvlist_t *propval = fnvlist_alloc(); 1364 nvlist_t *val = fnvlist_alloc(); 1365 1366 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1367 1368 /* 1369 * There may be missing entries in ds_next_clones_obj 1370 * due to a bug in a previous version of the code. 1371 * Only trust it if it has the right number of entries. 1372 */ 1373 if (ds->ds_phys->ds_next_clones_obj != 0) { 1374 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 1375 &count)); 1376 } 1377 if (count != ds->ds_phys->ds_num_children - 1) 1378 goto fail; 1379 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj); 1380 zap_cursor_retrieve(&zc, &za) == 0; 1381 zap_cursor_advance(&zc)) { 1382 dsl_dataset_t *clone; 1383 char buf[ZFS_MAXNAMELEN]; 1384 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1385 za.za_first_integer, FTAG, &clone)); 1386 dsl_dir_name(clone->ds_dir, buf); 1387 fnvlist_add_boolean(val, buf); 1388 dsl_dataset_rele(clone, FTAG); 1389 } 1390 zap_cursor_fini(&zc); 1391 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1392 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1393 fail: 1394 nvlist_free(val); 1395 nvlist_free(propval); 1396 } 1397 1398 void 1399 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1400 { 1401 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1402 uint64_t refd, avail, uobjs, aobjs, ratio; 1403 1404 ASSERT(dsl_pool_config_held(dp)); 1405 1406 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1407 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1408 ds->ds_phys->ds_compressed_bytes); 1409 1410 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1411 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1412 ds->ds_phys->ds_uncompressed_bytes); 1413 1414 if (dsl_dataset_is_snapshot(ds)) { 1415 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1416 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1417 ds->ds_phys->ds_unique_bytes); 1418 get_clones_stat(ds, nv); 1419 } else { 1420 dsl_dir_stats(ds->ds_dir, nv); 1421 } 1422 1423 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1424 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1425 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1426 1427 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1428 ds->ds_phys->ds_creation_time); 1429 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1430 ds->ds_phys->ds_creation_txg); 1431 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1432 ds->ds_quota); 1433 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1434 ds->ds_reserved); 1435 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1436 ds->ds_phys->ds_guid); 1437 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1438 ds->ds_phys->ds_unique_bytes); 1439 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1440 ds->ds_object); 1441 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1442 ds->ds_userrefs); 1443 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1444 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1445 1446 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1447 uint64_t written, comp, uncomp; 1448 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1449 dsl_dataset_t *prev; 1450 1451 int err = dsl_dataset_hold_obj(dp, 1452 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev); 1453 if (err == 0) { 1454 err = dsl_dataset_space_written(prev, ds, &written, 1455 &comp, &uncomp); 1456 dsl_dataset_rele(prev, FTAG); 1457 if (err == 0) { 1458 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1459 written); 1460 } 1461 } 1462 } 1463 } 1464 1465 void 1466 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1467 { 1468 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1469 ASSERT(dsl_pool_config_held(dp)); 1470 1471 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1472 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1473 stat->dds_guid = ds->ds_phys->ds_guid; 1474 stat->dds_origin[0] = '\0'; 1475 if (dsl_dataset_is_snapshot(ds)) { 1476 stat->dds_is_snapshot = B_TRUE; 1477 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1478 } else { 1479 stat->dds_is_snapshot = B_FALSE; 1480 stat->dds_num_clones = 0; 1481 1482 if (dsl_dir_is_clone(ds->ds_dir)) { 1483 dsl_dataset_t *ods; 1484 1485 VERIFY0(dsl_dataset_hold_obj(dp, 1486 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1487 dsl_dataset_name(ods, stat->dds_origin); 1488 dsl_dataset_rele(ods, FTAG); 1489 } 1490 } 1491 } 1492 1493 uint64_t 1494 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1495 { 1496 return (ds->ds_fsid_guid); 1497 } 1498 1499 void 1500 dsl_dataset_space(dsl_dataset_t *ds, 1501 uint64_t *refdbytesp, uint64_t *availbytesp, 1502 uint64_t *usedobjsp, uint64_t *availobjsp) 1503 { 1504 *refdbytesp = ds->ds_phys->ds_referenced_bytes; 1505 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1506 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1507 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1508 if (ds->ds_quota != 0) { 1509 /* 1510 * Adjust available bytes according to refquota 1511 */ 1512 if (*refdbytesp < ds->ds_quota) 1513 *availbytesp = MIN(*availbytesp, 1514 ds->ds_quota - *refdbytesp); 1515 else 1516 *availbytesp = 0; 1517 } 1518 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1519 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1520 } 1521 1522 boolean_t 1523 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds) 1524 { 1525 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1526 1527 ASSERT(dsl_pool_config_held(dp)); 1528 if (ds->ds_prev == NULL) 1529 return (B_FALSE); 1530 if (ds->ds_phys->ds_bp.blk_birth > 1531 ds->ds_prev->ds_phys->ds_creation_txg) { 1532 objset_t *os, *os_prev; 1533 /* 1534 * It may be that only the ZIL differs, because it was 1535 * reset in the head. Don't count that as being 1536 * modified. 1537 */ 1538 if (dmu_objset_from_ds(ds, &os) != 0) 1539 return (B_TRUE); 1540 if (dmu_objset_from_ds(ds->ds_prev, &os_prev) != 0) 1541 return (B_TRUE); 1542 return (bcmp(&os->os_phys->os_meta_dnode, 1543 &os_prev->os_phys->os_meta_dnode, 1544 sizeof (os->os_phys->os_meta_dnode)) != 0); 1545 } 1546 return (B_FALSE); 1547 } 1548 1549 typedef struct dsl_dataset_rename_snapshot_arg { 1550 const char *ddrsa_fsname; 1551 const char *ddrsa_oldsnapname; 1552 const char *ddrsa_newsnapname; 1553 boolean_t ddrsa_recursive; 1554 dmu_tx_t *ddrsa_tx; 1555 } dsl_dataset_rename_snapshot_arg_t; 1556 1557 /* ARGSUSED */ 1558 static int 1559 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1560 dsl_dataset_t *hds, void *arg) 1561 { 1562 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1563 int error; 1564 uint64_t val; 1565 1566 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1567 if (error != 0) { 1568 /* ignore nonexistent snapshots */ 1569 return (error == ENOENT ? 0 : error); 1570 } 1571 1572 /* new name should not exist */ 1573 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 1574 if (error == 0) 1575 error = SET_ERROR(EEXIST); 1576 else if (error == ENOENT) 1577 error = 0; 1578 1579 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1580 if (dsl_dir_namelen(hds->ds_dir) + 1 + 1581 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN) 1582 error = SET_ERROR(ENAMETOOLONG); 1583 1584 return (error); 1585 } 1586 1587 static int 1588 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 1589 { 1590 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1591 dsl_pool_t *dp = dmu_tx_pool(tx); 1592 dsl_dataset_t *hds; 1593 int error; 1594 1595 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 1596 if (error != 0) 1597 return (error); 1598 1599 if (ddrsa->ddrsa_recursive) { 1600 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1601 dsl_dataset_rename_snapshot_check_impl, ddrsa, 1602 DS_FIND_CHILDREN); 1603 } else { 1604 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 1605 } 1606 dsl_dataset_rele(hds, FTAG); 1607 return (error); 1608 } 1609 1610 static int 1611 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 1612 dsl_dataset_t *hds, void *arg) 1613 { 1614 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1615 dsl_dataset_t *ds; 1616 uint64_t val; 1617 dmu_tx_t *tx = ddrsa->ddrsa_tx; 1618 int error; 1619 1620 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1621 ASSERT(error == 0 || error == ENOENT); 1622 if (error == ENOENT) { 1623 /* ignore nonexistent snapshots */ 1624 return (0); 1625 } 1626 1627 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 1628 1629 /* log before we change the name */ 1630 spa_history_log_internal_ds(ds, "rename", tx, 1631 "-> @%s", ddrsa->ddrsa_newsnapname); 1632 1633 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx)); 1634 mutex_enter(&ds->ds_lock); 1635 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 1636 mutex_exit(&ds->ds_lock); 1637 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj, 1638 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 1639 1640 dsl_dataset_rele(ds, FTAG); 1641 return (0); 1642 } 1643 1644 static void 1645 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 1646 { 1647 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1648 dsl_pool_t *dp = dmu_tx_pool(tx); 1649 dsl_dataset_t *hds; 1650 1651 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 1652 ddrsa->ddrsa_tx = tx; 1653 if (ddrsa->ddrsa_recursive) { 1654 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1655 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 1656 DS_FIND_CHILDREN)); 1657 } else { 1658 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 1659 } 1660 dsl_dataset_rele(hds, FTAG); 1661 } 1662 1663 int 1664 dsl_dataset_rename_snapshot(const char *fsname, 1665 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 1666 { 1667 dsl_dataset_rename_snapshot_arg_t ddrsa; 1668 1669 ddrsa.ddrsa_fsname = fsname; 1670 ddrsa.ddrsa_oldsnapname = oldsnapname; 1671 ddrsa.ddrsa_newsnapname = newsnapname; 1672 ddrsa.ddrsa_recursive = recursive; 1673 1674 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 1675 dsl_dataset_rename_snapshot_sync, &ddrsa, 1)); 1676 } 1677 1678 /* 1679 * If we're doing an ownership handoff, we need to make sure that there is 1680 * only one long hold on the dataset. We're not allowed to change anything here 1681 * so we don't permanently release the long hold or regular hold here. We want 1682 * to do this only when syncing to avoid the dataset unexpectedly going away 1683 * when we release the long hold. 1684 */ 1685 static int 1686 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 1687 { 1688 boolean_t held; 1689 1690 if (!dmu_tx_is_syncing(tx)) 1691 return (0); 1692 1693 if (owner != NULL) { 1694 VERIFY3P(ds->ds_owner, ==, owner); 1695 dsl_dataset_long_rele(ds, owner); 1696 } 1697 1698 held = dsl_dataset_long_held(ds); 1699 1700 if (owner != NULL) 1701 dsl_dataset_long_hold(ds, owner); 1702 1703 if (held) 1704 return (SET_ERROR(EBUSY)); 1705 1706 return (0); 1707 } 1708 1709 typedef struct dsl_dataset_rollback_arg { 1710 const char *ddra_fsname; 1711 void *ddra_owner; 1712 } dsl_dataset_rollback_arg_t; 1713 1714 static int 1715 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 1716 { 1717 dsl_dataset_rollback_arg_t *ddra = arg; 1718 dsl_pool_t *dp = dmu_tx_pool(tx); 1719 dsl_dataset_t *ds; 1720 int64_t unused_refres_delta; 1721 int error; 1722 1723 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 1724 if (error != 0) 1725 return (error); 1726 1727 /* must not be a snapshot */ 1728 if (dsl_dataset_is_snapshot(ds)) { 1729 dsl_dataset_rele(ds, FTAG); 1730 return (SET_ERROR(EINVAL)); 1731 } 1732 1733 /* must have a most recent snapshot */ 1734 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) { 1735 dsl_dataset_rele(ds, FTAG); 1736 return (SET_ERROR(EINVAL)); 1737 } 1738 1739 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 1740 if (error != 0) { 1741 dsl_dataset_rele(ds, FTAG); 1742 return (error); 1743 } 1744 1745 /* 1746 * Check if the snap we are rolling back to uses more than 1747 * the refquota. 1748 */ 1749 if (ds->ds_quota != 0 && 1750 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) { 1751 dsl_dataset_rele(ds, FTAG); 1752 return (SET_ERROR(EDQUOT)); 1753 } 1754 1755 /* 1756 * When we do the clone swap, we will temporarily use more space 1757 * due to the refreservation (the head will no longer have any 1758 * unique space, so the entire amount of the refreservation will need 1759 * to be free). We will immediately destroy the clone, freeing 1760 * this space, but the freeing happens over many txg's. 1761 */ 1762 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 1763 ds->ds_phys->ds_unique_bytes); 1764 1765 if (unused_refres_delta > 0 && 1766 unused_refres_delta > 1767 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 1768 dsl_dataset_rele(ds, FTAG); 1769 return (SET_ERROR(ENOSPC)); 1770 } 1771 1772 dsl_dataset_rele(ds, FTAG); 1773 return (0); 1774 } 1775 1776 static void 1777 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 1778 { 1779 dsl_dataset_rollback_arg_t *ddra = arg; 1780 dsl_pool_t *dp = dmu_tx_pool(tx); 1781 dsl_dataset_t *ds, *clone; 1782 uint64_t cloneobj; 1783 1784 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 1785 1786 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 1787 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 1788 1789 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 1790 1791 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 1792 dsl_dataset_zero_zil(ds, tx); 1793 1794 dsl_destroy_head_sync_impl(clone, tx); 1795 1796 dsl_dataset_rele(clone, FTAG); 1797 dsl_dataset_rele(ds, FTAG); 1798 } 1799 1800 /* 1801 * If owner != NULL: 1802 * 1803 * - The existing dataset MUST be owned by the specified owner at entry 1804 * - Upon return, dataset will still be held by the same owner, whether we 1805 * succeed or not. 1806 * 1807 * This mode is required any time the existing filesystem is mounted. See 1808 * notes above zfs_suspend_fs() for further details. 1809 */ 1810 int 1811 dsl_dataset_rollback(const char *fsname, void *owner) 1812 { 1813 dsl_dataset_rollback_arg_t ddra; 1814 1815 ddra.ddra_fsname = fsname; 1816 ddra.ddra_owner = owner; 1817 1818 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 1819 dsl_dataset_rollback_sync, (void *)&ddra, 1)); 1820 } 1821 1822 struct promotenode { 1823 list_node_t link; 1824 dsl_dataset_t *ds; 1825 }; 1826 1827 typedef struct dsl_dataset_promote_arg { 1828 const char *ddpa_clonename; 1829 dsl_dataset_t *ddpa_clone; 1830 list_t shared_snaps, origin_snaps, clone_snaps; 1831 dsl_dataset_t *origin_origin; /* origin of the origin */ 1832 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 1833 char *err_ds; 1834 } dsl_dataset_promote_arg_t; 1835 1836 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 1837 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 1838 void *tag); 1839 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 1840 1841 static int 1842 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 1843 { 1844 dsl_dataset_promote_arg_t *ddpa = arg; 1845 dsl_pool_t *dp = dmu_tx_pool(tx); 1846 dsl_dataset_t *hds; 1847 struct promotenode *snap; 1848 dsl_dataset_t *origin_ds; 1849 int err; 1850 uint64_t unused; 1851 1852 err = promote_hold(ddpa, dp, FTAG); 1853 if (err != 0) 1854 return (err); 1855 1856 hds = ddpa->ddpa_clone; 1857 1858 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) { 1859 promote_rele(ddpa, FTAG); 1860 return (SET_ERROR(EXDEV)); 1861 } 1862 1863 /* 1864 * Compute and check the amount of space to transfer. Since this is 1865 * so expensive, don't do the preliminary check. 1866 */ 1867 if (!dmu_tx_is_syncing(tx)) { 1868 promote_rele(ddpa, FTAG); 1869 return (0); 1870 } 1871 1872 snap = list_head(&ddpa->shared_snaps); 1873 origin_ds = snap->ds; 1874 1875 /* compute origin's new unique space */ 1876 snap = list_tail(&ddpa->clone_snaps); 1877 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 1878 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 1879 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, 1880 &ddpa->unique, &unused, &unused); 1881 1882 /* 1883 * Walk the snapshots that we are moving 1884 * 1885 * Compute space to transfer. Consider the incremental changes 1886 * to used by each snapshot: 1887 * (my used) = (prev's used) + (blocks born) - (blocks killed) 1888 * So each snapshot gave birth to: 1889 * (blocks born) = (my used) - (prev's used) + (blocks killed) 1890 * So a sequence would look like: 1891 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 1892 * Which simplifies to: 1893 * uN + kN + kN-1 + ... + k1 + k0 1894 * Note however, if we stop before we reach the ORIGIN we get: 1895 * uN + kN + kN-1 + ... + kM - uM-1 1896 */ 1897 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes; 1898 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes; 1899 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 1900 for (snap = list_head(&ddpa->shared_snaps); snap; 1901 snap = list_next(&ddpa->shared_snaps, snap)) { 1902 uint64_t val, dlused, dlcomp, dluncomp; 1903 dsl_dataset_t *ds = snap->ds; 1904 1905 /* 1906 * If there are long holds, we won't be able to evict 1907 * the objset. 1908 */ 1909 if (dsl_dataset_long_held(ds)) { 1910 err = SET_ERROR(EBUSY); 1911 goto out; 1912 } 1913 1914 /* Check that the snapshot name does not conflict */ 1915 VERIFY0(dsl_dataset_get_snapname(ds)); 1916 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 1917 if (err == 0) { 1918 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 1919 err = SET_ERROR(EEXIST); 1920 goto out; 1921 } 1922 if (err != ENOENT) 1923 goto out; 1924 1925 /* The very first snapshot does not have a deadlist */ 1926 if (ds->ds_phys->ds_prev_snap_obj == 0) 1927 continue; 1928 1929 dsl_deadlist_space(&ds->ds_deadlist, 1930 &dlused, &dlcomp, &dluncomp); 1931 ddpa->used += dlused; 1932 ddpa->comp += dlcomp; 1933 ddpa->uncomp += dluncomp; 1934 } 1935 1936 /* 1937 * If we are a clone of a clone then we never reached ORIGIN, 1938 * so we need to subtract out the clone origin's used space. 1939 */ 1940 if (ddpa->origin_origin) { 1941 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes; 1942 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes; 1943 ddpa->uncomp -= 1944 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes; 1945 } 1946 1947 /* Check that there is enough space here */ 1948 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 1949 ddpa->used); 1950 if (err != 0) 1951 goto out; 1952 1953 /* 1954 * Compute the amounts of space that will be used by snapshots 1955 * after the promotion (for both origin and clone). For each, 1956 * it is the amount of space that will be on all of their 1957 * deadlists (that was not born before their new origin). 1958 */ 1959 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 1960 uint64_t space; 1961 1962 /* 1963 * Note, typically this will not be a clone of a clone, 1964 * so dd_origin_txg will be < TXG_INITIAL, so 1965 * these snaplist_space() -> dsl_deadlist_space_range() 1966 * calls will be fast because they do not have to 1967 * iterate over all bps. 1968 */ 1969 snap = list_head(&ddpa->origin_snaps); 1970 err = snaplist_space(&ddpa->shared_snaps, 1971 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 1972 if (err != 0) 1973 goto out; 1974 1975 err = snaplist_space(&ddpa->clone_snaps, 1976 snap->ds->ds_dir->dd_origin_txg, &space); 1977 if (err != 0) 1978 goto out; 1979 ddpa->cloneusedsnap += space; 1980 } 1981 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 1982 err = snaplist_space(&ddpa->origin_snaps, 1983 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap); 1984 if (err != 0) 1985 goto out; 1986 } 1987 1988 out: 1989 promote_rele(ddpa, FTAG); 1990 return (err); 1991 } 1992 1993 static void 1994 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 1995 { 1996 dsl_dataset_promote_arg_t *ddpa = arg; 1997 dsl_pool_t *dp = dmu_tx_pool(tx); 1998 dsl_dataset_t *hds; 1999 struct promotenode *snap; 2000 dsl_dataset_t *origin_ds; 2001 dsl_dataset_t *origin_head; 2002 dsl_dir_t *dd; 2003 dsl_dir_t *odd = NULL; 2004 uint64_t oldnext_obj; 2005 int64_t delta; 2006 2007 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2008 hds = ddpa->ddpa_clone; 2009 2010 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE); 2011 2012 snap = list_head(&ddpa->shared_snaps); 2013 origin_ds = snap->ds; 2014 dd = hds->ds_dir; 2015 2016 snap = list_head(&ddpa->origin_snaps); 2017 origin_head = snap->ds; 2018 2019 /* 2020 * We need to explicitly open odd, since origin_ds's dd will be 2021 * changing. 2022 */ 2023 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2024 NULL, FTAG, &odd)); 2025 2026 /* change origin's next snap */ 2027 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2028 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2029 snap = list_tail(&ddpa->clone_snaps); 2030 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2031 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2032 2033 /* change the origin's next clone */ 2034 if (origin_ds->ds_phys->ds_next_clones_obj) { 2035 dsl_dataset_remove_from_next_clones(origin_ds, 2036 snap->ds->ds_object, tx); 2037 VERIFY0(zap_add_int(dp->dp_meta_objset, 2038 origin_ds->ds_phys->ds_next_clones_obj, 2039 oldnext_obj, tx)); 2040 } 2041 2042 /* change origin */ 2043 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2044 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2045 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2046 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2047 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2048 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2049 origin_head->ds_dir->dd_origin_txg = 2050 origin_ds->ds_phys->ds_creation_txg; 2051 2052 /* change dd_clone entries */ 2053 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2054 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2055 odd->dd_phys->dd_clones, hds->ds_object, tx)); 2056 VERIFY0(zap_add_int(dp->dp_meta_objset, 2057 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2058 hds->ds_object, tx)); 2059 2060 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2061 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2062 origin_head->ds_object, tx)); 2063 if (dd->dd_phys->dd_clones == 0) { 2064 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset, 2065 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 2066 } 2067 VERIFY0(zap_add_int(dp->dp_meta_objset, 2068 dd->dd_phys->dd_clones, origin_head->ds_object, tx)); 2069 } 2070 2071 /* move snapshots to this dir */ 2072 for (snap = list_head(&ddpa->shared_snaps); snap; 2073 snap = list_next(&ddpa->shared_snaps, snap)) { 2074 dsl_dataset_t *ds = snap->ds; 2075 2076 /* 2077 * Property callbacks are registered to a particular 2078 * dsl_dir. Since ours is changing, evict the objset 2079 * so that they will be unregistered from the old dsl_dir. 2080 */ 2081 if (ds->ds_objset) { 2082 dmu_objset_evict(ds->ds_objset); 2083 ds->ds_objset = NULL; 2084 } 2085 2086 /* move snap name entry */ 2087 VERIFY0(dsl_dataset_get_snapname(ds)); 2088 VERIFY0(dsl_dataset_snap_remove(origin_head, 2089 ds->ds_snapname, tx)); 2090 VERIFY0(zap_add(dp->dp_meta_objset, 2091 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2092 8, 1, &ds->ds_object, tx)); 2093 2094 /* change containing dsl_dir */ 2095 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2096 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2097 ds->ds_phys->ds_dir_obj = dd->dd_object; 2098 ASSERT3P(ds->ds_dir, ==, odd); 2099 dsl_dir_rele(ds->ds_dir, ds); 2100 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2101 NULL, ds, &ds->ds_dir)); 2102 2103 /* move any clone references */ 2104 if (ds->ds_phys->ds_next_clones_obj && 2105 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2106 zap_cursor_t zc; 2107 zap_attribute_t za; 2108 2109 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2110 ds->ds_phys->ds_next_clones_obj); 2111 zap_cursor_retrieve(&zc, &za) == 0; 2112 zap_cursor_advance(&zc)) { 2113 dsl_dataset_t *cnds; 2114 uint64_t o; 2115 2116 if (za.za_first_integer == oldnext_obj) { 2117 /* 2118 * We've already moved the 2119 * origin's reference. 2120 */ 2121 continue; 2122 } 2123 2124 VERIFY0(dsl_dataset_hold_obj(dp, 2125 za.za_first_integer, FTAG, &cnds)); 2126 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj; 2127 2128 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2129 odd->dd_phys->dd_clones, o, tx)); 2130 VERIFY0(zap_add_int(dp->dp_meta_objset, 2131 dd->dd_phys->dd_clones, o, tx)); 2132 dsl_dataset_rele(cnds, FTAG); 2133 } 2134 zap_cursor_fini(&zc); 2135 } 2136 2137 ASSERT(!dsl_prop_hascb(ds)); 2138 } 2139 2140 /* 2141 * Change space accounting. 2142 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2143 * both be valid, or both be 0 (resulting in delta == 0). This 2144 * is true for each of {clone,origin} independently. 2145 */ 2146 2147 delta = ddpa->cloneusedsnap - 2148 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2149 ASSERT3S(delta, >=, 0); 2150 ASSERT3U(ddpa->used, >=, delta); 2151 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2152 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2153 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2154 2155 delta = ddpa->originusedsnap - 2156 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2157 ASSERT3S(delta, <=, 0); 2158 ASSERT3U(ddpa->used, >=, -delta); 2159 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2160 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2161 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2162 2163 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique; 2164 2165 /* log history record */ 2166 spa_history_log_internal_ds(hds, "promote", tx, ""); 2167 2168 dsl_dir_rele(odd, FTAG); 2169 promote_rele(ddpa, FTAG); 2170 } 2171 2172 /* 2173 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2174 * (exclusive) and last_obj (inclusive). The list will be in reverse 2175 * order (last_obj will be the list_head()). If first_obj == 0, do all 2176 * snapshots back to this dataset's origin. 2177 */ 2178 static int 2179 snaplist_make(dsl_pool_t *dp, 2180 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2181 { 2182 uint64_t obj = last_obj; 2183 2184 list_create(l, sizeof (struct promotenode), 2185 offsetof(struct promotenode, link)); 2186 2187 while (obj != first_obj) { 2188 dsl_dataset_t *ds; 2189 struct promotenode *snap; 2190 int err; 2191 2192 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2193 ASSERT(err != ENOENT); 2194 if (err != 0) 2195 return (err); 2196 2197 if (first_obj == 0) 2198 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2199 2200 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2201 snap->ds = ds; 2202 list_insert_tail(l, snap); 2203 obj = ds->ds_phys->ds_prev_snap_obj; 2204 } 2205 2206 return (0); 2207 } 2208 2209 static int 2210 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2211 { 2212 struct promotenode *snap; 2213 2214 *spacep = 0; 2215 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2216 uint64_t used, comp, uncomp; 2217 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2218 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2219 *spacep += used; 2220 } 2221 return (0); 2222 } 2223 2224 static void 2225 snaplist_destroy(list_t *l, void *tag) 2226 { 2227 struct promotenode *snap; 2228 2229 if (l == NULL || !list_link_active(&l->list_head)) 2230 return; 2231 2232 while ((snap = list_tail(l)) != NULL) { 2233 list_remove(l, snap); 2234 dsl_dataset_rele(snap->ds, tag); 2235 kmem_free(snap, sizeof (*snap)); 2236 } 2237 list_destroy(l); 2238 } 2239 2240 static int 2241 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2242 { 2243 int error; 2244 dsl_dir_t *dd; 2245 struct promotenode *snap; 2246 2247 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2248 &ddpa->ddpa_clone); 2249 if (error != 0) 2250 return (error); 2251 dd = ddpa->ddpa_clone->ds_dir; 2252 2253 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) || 2254 !dsl_dir_is_clone(dd)) { 2255 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2256 return (SET_ERROR(EINVAL)); 2257 } 2258 2259 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj, 2260 &ddpa->shared_snaps, tag); 2261 if (error != 0) 2262 goto out; 2263 2264 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2265 &ddpa->clone_snaps, tag); 2266 if (error != 0) 2267 goto out; 2268 2269 snap = list_head(&ddpa->shared_snaps); 2270 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2271 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj, 2272 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, 2273 &ddpa->origin_snaps, tag); 2274 if (error != 0) 2275 goto out; 2276 2277 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) { 2278 error = dsl_dataset_hold_obj(dp, 2279 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2280 tag, &ddpa->origin_origin); 2281 if (error != 0) 2282 goto out; 2283 } 2284 out: 2285 if (error != 0) 2286 promote_rele(ddpa, tag); 2287 return (error); 2288 } 2289 2290 static void 2291 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2292 { 2293 snaplist_destroy(&ddpa->shared_snaps, tag); 2294 snaplist_destroy(&ddpa->clone_snaps, tag); 2295 snaplist_destroy(&ddpa->origin_snaps, tag); 2296 if (ddpa->origin_origin != NULL) 2297 dsl_dataset_rele(ddpa->origin_origin, tag); 2298 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2299 } 2300 2301 /* 2302 * Promote a clone. 2303 * 2304 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2305 * in with the name. (It must be at least MAXNAMELEN bytes long.) 2306 */ 2307 int 2308 dsl_dataset_promote(const char *name, char *conflsnap) 2309 { 2310 dsl_dataset_promote_arg_t ddpa = { 0 }; 2311 uint64_t numsnaps; 2312 int error; 2313 objset_t *os; 2314 2315 /* 2316 * We will modify space proportional to the number of 2317 * snapshots. Compute numsnaps. 2318 */ 2319 error = dmu_objset_hold(name, FTAG, &os); 2320 if (error != 0) 2321 return (error); 2322 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2323 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps); 2324 dmu_objset_rele(os, FTAG); 2325 if (error != 0) 2326 return (error); 2327 2328 ddpa.ddpa_clonename = name; 2329 ddpa.err_ds = conflsnap; 2330 2331 return (dsl_sync_task(name, dsl_dataset_promote_check, 2332 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps)); 2333 } 2334 2335 int 2336 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2337 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2338 { 2339 int64_t unused_refres_delta; 2340 2341 /* they should both be heads */ 2342 if (dsl_dataset_is_snapshot(clone) || 2343 dsl_dataset_is_snapshot(origin_head)) 2344 return (SET_ERROR(EINVAL)); 2345 2346 /* the branch point should be just before them */ 2347 if (clone->ds_prev != origin_head->ds_prev) 2348 return (SET_ERROR(EINVAL)); 2349 2350 /* clone should be the clone (unless they are unrelated) */ 2351 if (clone->ds_prev != NULL && 2352 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2353 origin_head->ds_object != 2354 clone->ds_prev->ds_phys->ds_next_snap_obj) 2355 return (SET_ERROR(EINVAL)); 2356 2357 /* the clone should be a child of the origin */ 2358 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2359 return (SET_ERROR(EINVAL)); 2360 2361 /* origin_head shouldn't be modified unless 'force' */ 2362 if (!force && dsl_dataset_modified_since_lastsnap(origin_head)) 2363 return (SET_ERROR(ETXTBSY)); 2364 2365 /* origin_head should have no long holds (e.g. is not mounted) */ 2366 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2367 return (SET_ERROR(EBUSY)); 2368 2369 /* check amount of any unconsumed refreservation */ 2370 unused_refres_delta = 2371 (int64_t)MIN(origin_head->ds_reserved, 2372 origin_head->ds_phys->ds_unique_bytes) - 2373 (int64_t)MIN(origin_head->ds_reserved, 2374 clone->ds_phys->ds_unique_bytes); 2375 2376 if (unused_refres_delta > 0 && 2377 unused_refres_delta > 2378 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2379 return (SET_ERROR(ENOSPC)); 2380 2381 /* clone can't be over the head's refquota */ 2382 if (origin_head->ds_quota != 0 && 2383 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota) 2384 return (SET_ERROR(EDQUOT)); 2385 2386 return (0); 2387 } 2388 2389 void 2390 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2391 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2392 { 2393 dsl_pool_t *dp = dmu_tx_pool(tx); 2394 int64_t unused_refres_delta; 2395 2396 ASSERT(clone->ds_reserved == 0); 2397 ASSERT(origin_head->ds_quota == 0 || 2398 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota); 2399 2400 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2401 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2402 2403 if (clone->ds_objset != NULL) { 2404 dmu_objset_evict(clone->ds_objset); 2405 clone->ds_objset = NULL; 2406 } 2407 2408 if (origin_head->ds_objset != NULL) { 2409 dmu_objset_evict(origin_head->ds_objset); 2410 origin_head->ds_objset = NULL; 2411 } 2412 2413 unused_refres_delta = 2414 (int64_t)MIN(origin_head->ds_reserved, 2415 origin_head->ds_phys->ds_unique_bytes) - 2416 (int64_t)MIN(origin_head->ds_reserved, 2417 clone->ds_phys->ds_unique_bytes); 2418 2419 /* 2420 * Reset origin's unique bytes, if it exists. 2421 */ 2422 if (clone->ds_prev) { 2423 dsl_dataset_t *origin = clone->ds_prev; 2424 uint64_t comp, uncomp; 2425 2426 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2427 dsl_deadlist_space_range(&clone->ds_deadlist, 2428 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2429 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp); 2430 } 2431 2432 /* swap blkptrs */ 2433 { 2434 blkptr_t tmp; 2435 tmp = origin_head->ds_phys->ds_bp; 2436 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp; 2437 clone->ds_phys->ds_bp = tmp; 2438 } 2439 2440 /* set dd_*_bytes */ 2441 { 2442 int64_t dused, dcomp, duncomp; 2443 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2444 uint64_t odl_used, odl_comp, odl_uncomp; 2445 2446 ASSERT3U(clone->ds_dir->dd_phys-> 2447 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2448 2449 dsl_deadlist_space(&clone->ds_deadlist, 2450 &cdl_used, &cdl_comp, &cdl_uncomp); 2451 dsl_deadlist_space(&origin_head->ds_deadlist, 2452 &odl_used, &odl_comp, &odl_uncomp); 2453 2454 dused = clone->ds_phys->ds_referenced_bytes + cdl_used - 2455 (origin_head->ds_phys->ds_referenced_bytes + odl_used); 2456 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp - 2457 (origin_head->ds_phys->ds_compressed_bytes + odl_comp); 2458 duncomp = clone->ds_phys->ds_uncompressed_bytes + 2459 cdl_uncomp - 2460 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2461 2462 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 2463 dused, dcomp, duncomp, tx); 2464 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 2465 -dused, -dcomp, -duncomp, tx); 2466 2467 /* 2468 * The difference in the space used by snapshots is the 2469 * difference in snapshot space due to the head's 2470 * deadlist (since that's the only thing that's 2471 * changing that affects the snapused). 2472 */ 2473 dsl_deadlist_space_range(&clone->ds_deadlist, 2474 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2475 &cdl_used, &cdl_comp, &cdl_uncomp); 2476 dsl_deadlist_space_range(&origin_head->ds_deadlist, 2477 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2478 &odl_used, &odl_comp, &odl_uncomp); 2479 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 2480 DD_USED_HEAD, DD_USED_SNAP, tx); 2481 } 2482 2483 /* swap ds_*_bytes */ 2484 SWITCH64(origin_head->ds_phys->ds_referenced_bytes, 2485 clone->ds_phys->ds_referenced_bytes); 2486 SWITCH64(origin_head->ds_phys->ds_compressed_bytes, 2487 clone->ds_phys->ds_compressed_bytes); 2488 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes, 2489 clone->ds_phys->ds_uncompressed_bytes); 2490 SWITCH64(origin_head->ds_phys->ds_unique_bytes, 2491 clone->ds_phys->ds_unique_bytes); 2492 2493 /* apply any parent delta for change in unconsumed refreservation */ 2494 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 2495 unused_refres_delta, 0, 0, tx); 2496 2497 /* 2498 * Swap deadlists. 2499 */ 2500 dsl_deadlist_close(&clone->ds_deadlist); 2501 dsl_deadlist_close(&origin_head->ds_deadlist); 2502 SWITCH64(origin_head->ds_phys->ds_deadlist_obj, 2503 clone->ds_phys->ds_deadlist_obj); 2504 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 2505 clone->ds_phys->ds_deadlist_obj); 2506 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 2507 origin_head->ds_phys->ds_deadlist_obj); 2508 2509 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 2510 2511 spa_history_log_internal_ds(clone, "clone swap", tx, 2512 "parent=%s", origin_head->ds_dir->dd_myname); 2513 } 2514 2515 /* 2516 * Given a pool name and a dataset object number in that pool, 2517 * return the name of that dataset. 2518 */ 2519 int 2520 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2521 { 2522 dsl_pool_t *dp; 2523 dsl_dataset_t *ds; 2524 int error; 2525 2526 error = dsl_pool_hold(pname, FTAG, &dp); 2527 if (error != 0) 2528 return (error); 2529 2530 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 2531 if (error == 0) { 2532 dsl_dataset_name(ds, buf); 2533 dsl_dataset_rele(ds, FTAG); 2534 } 2535 dsl_pool_rele(dp, FTAG); 2536 2537 return (error); 2538 } 2539 2540 int 2541 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2542 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2543 { 2544 int error = 0; 2545 2546 ASSERT3S(asize, >, 0); 2547 2548 /* 2549 * *ref_rsrv is the portion of asize that will come from any 2550 * unconsumed refreservation space. 2551 */ 2552 *ref_rsrv = 0; 2553 2554 mutex_enter(&ds->ds_lock); 2555 /* 2556 * Make a space adjustment for reserved bytes. 2557 */ 2558 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2559 ASSERT3U(*used, >=, 2560 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2561 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2562 *ref_rsrv = 2563 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2564 } 2565 2566 if (!check_quota || ds->ds_quota == 0) { 2567 mutex_exit(&ds->ds_lock); 2568 return (0); 2569 } 2570 /* 2571 * If they are requesting more space, and our current estimate 2572 * is over quota, they get to try again unless the actual 2573 * on-disk is over quota and there are no pending changes (which 2574 * may free up space for us). 2575 */ 2576 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) { 2577 if (inflight > 0 || 2578 ds->ds_phys->ds_referenced_bytes < ds->ds_quota) 2579 error = SET_ERROR(ERESTART); 2580 else 2581 error = SET_ERROR(EDQUOT); 2582 } 2583 mutex_exit(&ds->ds_lock); 2584 2585 return (error); 2586 } 2587 2588 typedef struct dsl_dataset_set_qr_arg { 2589 const char *ddsqra_name; 2590 zprop_source_t ddsqra_source; 2591 uint64_t ddsqra_value; 2592 } dsl_dataset_set_qr_arg_t; 2593 2594 2595 /* ARGSUSED */ 2596 static int 2597 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 2598 { 2599 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2600 dsl_pool_t *dp = dmu_tx_pool(tx); 2601 dsl_dataset_t *ds; 2602 int error; 2603 uint64_t newval; 2604 2605 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 2606 return (SET_ERROR(ENOTSUP)); 2607 2608 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2609 if (error != 0) 2610 return (error); 2611 2612 if (dsl_dataset_is_snapshot(ds)) { 2613 dsl_dataset_rele(ds, FTAG); 2614 return (SET_ERROR(EINVAL)); 2615 } 2616 2617 error = dsl_prop_predict(ds->ds_dir, 2618 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2619 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2620 if (error != 0) { 2621 dsl_dataset_rele(ds, FTAG); 2622 return (error); 2623 } 2624 2625 if (newval == 0) { 2626 dsl_dataset_rele(ds, FTAG); 2627 return (0); 2628 } 2629 2630 if (newval < ds->ds_phys->ds_referenced_bytes || 2631 newval < ds->ds_reserved) { 2632 dsl_dataset_rele(ds, FTAG); 2633 return (SET_ERROR(ENOSPC)); 2634 } 2635 2636 dsl_dataset_rele(ds, FTAG); 2637 return (0); 2638 } 2639 2640 static void 2641 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 2642 { 2643 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2644 dsl_pool_t *dp = dmu_tx_pool(tx); 2645 dsl_dataset_t *ds; 2646 uint64_t newval; 2647 2648 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2649 2650 dsl_prop_set_sync_impl(ds, 2651 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2652 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 2653 &ddsqra->ddsqra_value, tx); 2654 2655 VERIFY0(dsl_prop_get_int_ds(ds, 2656 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 2657 2658 if (ds->ds_quota != newval) { 2659 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2660 ds->ds_quota = newval; 2661 } 2662 dsl_dataset_rele(ds, FTAG); 2663 } 2664 2665 int 2666 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 2667 uint64_t refquota) 2668 { 2669 dsl_dataset_set_qr_arg_t ddsqra; 2670 2671 ddsqra.ddsqra_name = dsname; 2672 ddsqra.ddsqra_source = source; 2673 ddsqra.ddsqra_value = refquota; 2674 2675 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 2676 dsl_dataset_set_refquota_sync, &ddsqra, 0)); 2677 } 2678 2679 static int 2680 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 2681 { 2682 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2683 dsl_pool_t *dp = dmu_tx_pool(tx); 2684 dsl_dataset_t *ds; 2685 int error; 2686 uint64_t newval, unique; 2687 2688 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 2689 return (SET_ERROR(ENOTSUP)); 2690 2691 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2692 if (error != 0) 2693 return (error); 2694 2695 if (dsl_dataset_is_snapshot(ds)) { 2696 dsl_dataset_rele(ds, FTAG); 2697 return (SET_ERROR(EINVAL)); 2698 } 2699 2700 error = dsl_prop_predict(ds->ds_dir, 2701 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2702 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2703 if (error != 0) { 2704 dsl_dataset_rele(ds, FTAG); 2705 return (error); 2706 } 2707 2708 /* 2709 * If we are doing the preliminary check in open context, the 2710 * space estimates may be inaccurate. 2711 */ 2712 if (!dmu_tx_is_syncing(tx)) { 2713 dsl_dataset_rele(ds, FTAG); 2714 return (0); 2715 } 2716 2717 mutex_enter(&ds->ds_lock); 2718 if (!DS_UNIQUE_IS_ACCURATE(ds)) 2719 dsl_dataset_recalc_head_uniq(ds); 2720 unique = ds->ds_phys->ds_unique_bytes; 2721 mutex_exit(&ds->ds_lock); 2722 2723 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 2724 uint64_t delta = MAX(unique, newval) - 2725 MAX(unique, ds->ds_reserved); 2726 2727 if (delta > 2728 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 2729 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 2730 dsl_dataset_rele(ds, FTAG); 2731 return (SET_ERROR(ENOSPC)); 2732 } 2733 } 2734 2735 dsl_dataset_rele(ds, FTAG); 2736 return (0); 2737 } 2738 2739 void 2740 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 2741 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 2742 { 2743 uint64_t newval; 2744 uint64_t unique; 2745 int64_t delta; 2746 2747 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2748 source, sizeof (value), 1, &value, tx); 2749 2750 VERIFY0(dsl_prop_get_int_ds(ds, 2751 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 2752 2753 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2754 mutex_enter(&ds->ds_dir->dd_lock); 2755 mutex_enter(&ds->ds_lock); 2756 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 2757 unique = ds->ds_phys->ds_unique_bytes; 2758 delta = MAX(0, (int64_t)(newval - unique)) - 2759 MAX(0, (int64_t)(ds->ds_reserved - unique)); 2760 ds->ds_reserved = newval; 2761 mutex_exit(&ds->ds_lock); 2762 2763 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 2764 mutex_exit(&ds->ds_dir->dd_lock); 2765 } 2766 2767 static void 2768 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 2769 { 2770 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2771 dsl_pool_t *dp = dmu_tx_pool(tx); 2772 dsl_dataset_t *ds; 2773 2774 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2775 dsl_dataset_set_refreservation_sync_impl(ds, 2776 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 2777 dsl_dataset_rele(ds, FTAG); 2778 } 2779 2780 int 2781 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 2782 uint64_t refreservation) 2783 { 2784 dsl_dataset_set_qr_arg_t ddsqra; 2785 2786 ddsqra.ddsqra_name = dsname; 2787 ddsqra.ddsqra_source = source; 2788 ddsqra.ddsqra_value = refreservation; 2789 2790 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 2791 dsl_dataset_set_refreservation_sync, &ddsqra, 0)); 2792 } 2793 2794 /* 2795 * Return (in *usedp) the amount of space written in new that is not 2796 * present in oldsnap. New may be a snapshot or the head. Old must be 2797 * a snapshot before new, in new's filesystem (or its origin). If not then 2798 * fail and return EINVAL. 2799 * 2800 * The written space is calculated by considering two components: First, we 2801 * ignore any freed space, and calculate the written as new's used space 2802 * minus old's used space. Next, we add in the amount of space that was freed 2803 * between the two snapshots, thus reducing new's used space relative to old's. 2804 * Specifically, this is the space that was born before old->ds_creation_txg, 2805 * and freed before new (ie. on new's deadlist or a previous deadlist). 2806 * 2807 * space freed [---------------------] 2808 * snapshots ---O-------O--------O-------O------ 2809 * oldsnap new 2810 */ 2811 int 2812 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 2813 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2814 { 2815 int err = 0; 2816 uint64_t snapobj; 2817 dsl_pool_t *dp = new->ds_dir->dd_pool; 2818 2819 ASSERT(dsl_pool_config_held(dp)); 2820 2821 *usedp = 0; 2822 *usedp += new->ds_phys->ds_referenced_bytes; 2823 *usedp -= oldsnap->ds_phys->ds_referenced_bytes; 2824 2825 *compp = 0; 2826 *compp += new->ds_phys->ds_compressed_bytes; 2827 *compp -= oldsnap->ds_phys->ds_compressed_bytes; 2828 2829 *uncompp = 0; 2830 *uncompp += new->ds_phys->ds_uncompressed_bytes; 2831 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes; 2832 2833 snapobj = new->ds_object; 2834 while (snapobj != oldsnap->ds_object) { 2835 dsl_dataset_t *snap; 2836 uint64_t used, comp, uncomp; 2837 2838 if (snapobj == new->ds_object) { 2839 snap = new; 2840 } else { 2841 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 2842 if (err != 0) 2843 break; 2844 } 2845 2846 if (snap->ds_phys->ds_prev_snap_txg == 2847 oldsnap->ds_phys->ds_creation_txg) { 2848 /* 2849 * The blocks in the deadlist can not be born after 2850 * ds_prev_snap_txg, so get the whole deadlist space, 2851 * which is more efficient (especially for old-format 2852 * deadlists). Unfortunately the deadlist code 2853 * doesn't have enough information to make this 2854 * optimization itself. 2855 */ 2856 dsl_deadlist_space(&snap->ds_deadlist, 2857 &used, &comp, &uncomp); 2858 } else { 2859 dsl_deadlist_space_range(&snap->ds_deadlist, 2860 0, oldsnap->ds_phys->ds_creation_txg, 2861 &used, &comp, &uncomp); 2862 } 2863 *usedp += used; 2864 *compp += comp; 2865 *uncompp += uncomp; 2866 2867 /* 2868 * If we get to the beginning of the chain of snapshots 2869 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 2870 * was not a snapshot of/before new. 2871 */ 2872 snapobj = snap->ds_phys->ds_prev_snap_obj; 2873 if (snap != new) 2874 dsl_dataset_rele(snap, FTAG); 2875 if (snapobj == 0) { 2876 err = SET_ERROR(EINVAL); 2877 break; 2878 } 2879 2880 } 2881 return (err); 2882 } 2883 2884 /* 2885 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 2886 * lastsnap, and all snapshots in between are deleted. 2887 * 2888 * blocks that would be freed [---------------------------] 2889 * snapshots ---O-------O--------O-------O--------O 2890 * firstsnap lastsnap 2891 * 2892 * This is the set of blocks that were born after the snap before firstsnap, 2893 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 2894 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 2895 * We calculate this by iterating over the relevant deadlists (from the snap 2896 * after lastsnap, backward to the snap after firstsnap), summing up the 2897 * space on the deadlist that was born after the snap before firstsnap. 2898 */ 2899 int 2900 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 2901 dsl_dataset_t *lastsnap, 2902 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2903 { 2904 int err = 0; 2905 uint64_t snapobj; 2906 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 2907 2908 ASSERT(dsl_dataset_is_snapshot(firstsnap)); 2909 ASSERT(dsl_dataset_is_snapshot(lastsnap)); 2910 2911 /* 2912 * Check that the snapshots are in the same dsl_dir, and firstsnap 2913 * is before lastsnap. 2914 */ 2915 if (firstsnap->ds_dir != lastsnap->ds_dir || 2916 firstsnap->ds_phys->ds_creation_txg > 2917 lastsnap->ds_phys->ds_creation_txg) 2918 return (SET_ERROR(EINVAL)); 2919 2920 *usedp = *compp = *uncompp = 0; 2921 2922 snapobj = lastsnap->ds_phys->ds_next_snap_obj; 2923 while (snapobj != firstsnap->ds_object) { 2924 dsl_dataset_t *ds; 2925 uint64_t used, comp, uncomp; 2926 2927 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 2928 if (err != 0) 2929 break; 2930 2931 dsl_deadlist_space_range(&ds->ds_deadlist, 2932 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2933 &used, &comp, &uncomp); 2934 *usedp += used; 2935 *compp += comp; 2936 *uncompp += uncomp; 2937 2938 snapobj = ds->ds_phys->ds_prev_snap_obj; 2939 ASSERT3U(snapobj, !=, 0); 2940 dsl_dataset_rele(ds, FTAG); 2941 } 2942 return (err); 2943 } 2944 2945 /* 2946 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 2947 * For example, they could both be snapshots of the same filesystem, and 2948 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 2949 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 2950 * filesystem. Or 'earlier' could be the origin's origin. 2951 */ 2952 boolean_t 2953 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier) 2954 { 2955 dsl_pool_t *dp = later->ds_dir->dd_pool; 2956 int error; 2957 boolean_t ret; 2958 2959 ASSERT(dsl_pool_config_held(dp)); 2960 2961 if (earlier->ds_phys->ds_creation_txg >= 2962 later->ds_phys->ds_creation_txg) 2963 return (B_FALSE); 2964 2965 if (later->ds_dir == earlier->ds_dir) 2966 return (B_TRUE); 2967 if (!dsl_dir_is_clone(later->ds_dir)) 2968 return (B_FALSE); 2969 2970 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object) 2971 return (B_TRUE); 2972 dsl_dataset_t *origin; 2973 error = dsl_dataset_hold_obj(dp, 2974 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin); 2975 if (error != 0) 2976 return (B_FALSE); 2977 ret = dsl_dataset_is_before(origin, earlier); 2978 dsl_dataset_rele(origin, FTAG); 2979 return (ret); 2980 } 2981