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, boolean_t recv) 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 /* 977 * We don't allow taking snapshots of inconsistent datasets, such as 978 * those into which we are currently receiving. However, if we are 979 * creating this snapshot as part of a receive, this check will be 980 * executed atomically with respect to the completion of the receive 981 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 982 * case we ignore this, knowing it will be fixed up for us shortly in 983 * dmu_recv_end_sync(). 984 */ 985 if (!recv && DS_IS_INCONSISTENT(ds)) 986 return (SET_ERROR(EBUSY)); 987 988 error = dsl_dataset_snapshot_reserve_space(ds, tx); 989 if (error != 0) 990 return (error); 991 992 return (0); 993 } 994 995 static int 996 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 997 { 998 dsl_dataset_snapshot_arg_t *ddsa = arg; 999 dsl_pool_t *dp = dmu_tx_pool(tx); 1000 nvpair_t *pair; 1001 int rv = 0; 1002 1003 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1004 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1005 int error = 0; 1006 dsl_dataset_t *ds; 1007 char *name, *atp; 1008 char dsname[MAXNAMELEN]; 1009 1010 name = nvpair_name(pair); 1011 if (strlen(name) >= MAXNAMELEN) 1012 error = SET_ERROR(ENAMETOOLONG); 1013 if (error == 0) { 1014 atp = strchr(name, '@'); 1015 if (atp == NULL) 1016 error = SET_ERROR(EINVAL); 1017 if (error == 0) 1018 (void) strlcpy(dsname, name, atp - name + 1); 1019 } 1020 if (error == 0) 1021 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1022 if (error == 0) { 1023 error = dsl_dataset_snapshot_check_impl(ds, 1024 atp + 1, tx, B_FALSE); 1025 dsl_dataset_rele(ds, FTAG); 1026 } 1027 1028 if (error != 0) { 1029 if (ddsa->ddsa_errors != NULL) { 1030 fnvlist_add_int32(ddsa->ddsa_errors, 1031 name, error); 1032 } 1033 rv = error; 1034 } 1035 } 1036 return (rv); 1037 } 1038 1039 void 1040 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1041 dmu_tx_t *tx) 1042 { 1043 static zil_header_t zero_zil; 1044 1045 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1046 dmu_buf_t *dbuf; 1047 dsl_dataset_phys_t *dsphys; 1048 uint64_t dsobj, crtxg; 1049 objset_t *mos = dp->dp_meta_objset; 1050 objset_t *os; 1051 1052 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1053 1054 /* 1055 * If we are on an old pool, the zil must not be active, in which 1056 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1057 */ 1058 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1059 dmu_objset_from_ds(ds, &os) != 0 || 1060 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1061 sizeof (zero_zil)) == 0); 1062 1063 1064 /* 1065 * The origin's ds_creation_txg has to be < TXG_INITIAL 1066 */ 1067 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1068 crtxg = 1; 1069 else 1070 crtxg = tx->tx_txg; 1071 1072 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1073 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1074 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1075 dmu_buf_will_dirty(dbuf, tx); 1076 dsphys = dbuf->db_data; 1077 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1078 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1079 dsphys->ds_fsid_guid = unique_create(); 1080 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1081 sizeof (dsphys->ds_guid)); 1082 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1083 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1084 dsphys->ds_next_snap_obj = ds->ds_object; 1085 dsphys->ds_num_children = 1; 1086 dsphys->ds_creation_time = gethrestime_sec(); 1087 dsphys->ds_creation_txg = crtxg; 1088 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1089 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes; 1090 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1091 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1092 dsphys->ds_flags = ds->ds_phys->ds_flags; 1093 dsphys->ds_bp = ds->ds_phys->ds_bp; 1094 dmu_buf_rele(dbuf, FTAG); 1095 1096 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1097 if (ds->ds_prev) { 1098 uint64_t next_clones_obj = 1099 ds->ds_prev->ds_phys->ds_next_clones_obj; 1100 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1101 ds->ds_object || 1102 ds->ds_prev->ds_phys->ds_num_children > 1); 1103 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1104 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1105 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1106 ds->ds_prev->ds_phys->ds_creation_txg); 1107 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1108 } else if (next_clones_obj != 0) { 1109 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1110 dsphys->ds_next_snap_obj, tx); 1111 VERIFY0(zap_add_int(mos, 1112 next_clones_obj, dsobj, tx)); 1113 } 1114 } 1115 1116 /* 1117 * If we have a reference-reservation on this dataset, we will 1118 * need to increase the amount of refreservation being charged 1119 * since our unique space is going to zero. 1120 */ 1121 if (ds->ds_reserved) { 1122 int64_t delta; 1123 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1124 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 1125 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1126 delta, 0, 0, tx); 1127 } 1128 1129 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1130 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist, 1131 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx); 1132 dsl_deadlist_close(&ds->ds_deadlist); 1133 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj); 1134 dsl_deadlist_add_key(&ds->ds_deadlist, 1135 ds->ds_phys->ds_prev_snap_txg, tx); 1136 1137 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1138 ds->ds_phys->ds_prev_snap_obj = dsobj; 1139 ds->ds_phys->ds_prev_snap_txg = crtxg; 1140 ds->ds_phys->ds_unique_bytes = 0; 1141 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1142 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1143 1144 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1145 snapname, 8, 1, &dsobj, tx)); 1146 1147 if (ds->ds_prev) 1148 dsl_dataset_rele(ds->ds_prev, ds); 1149 VERIFY0(dsl_dataset_hold_obj(dp, 1150 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1151 1152 dsl_scan_ds_snapshotted(ds, tx); 1153 1154 dsl_dir_snap_cmtime_update(ds->ds_dir); 1155 1156 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1157 } 1158 1159 static void 1160 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1161 { 1162 dsl_dataset_snapshot_arg_t *ddsa = arg; 1163 dsl_pool_t *dp = dmu_tx_pool(tx); 1164 nvpair_t *pair; 1165 1166 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1167 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1168 dsl_dataset_t *ds; 1169 char *name, *atp; 1170 char dsname[MAXNAMELEN]; 1171 1172 name = nvpair_name(pair); 1173 atp = strchr(name, '@'); 1174 (void) strlcpy(dsname, name, atp - name + 1); 1175 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1176 1177 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1178 if (ddsa->ddsa_props != NULL) { 1179 dsl_props_set_sync_impl(ds->ds_prev, 1180 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1181 } 1182 dsl_dataset_rele(ds, FTAG); 1183 } 1184 } 1185 1186 /* 1187 * The snapshots must all be in the same pool. 1188 * All-or-nothing: if there are any failures, nothing will be modified. 1189 */ 1190 int 1191 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1192 { 1193 dsl_dataset_snapshot_arg_t ddsa; 1194 nvpair_t *pair; 1195 boolean_t needsuspend; 1196 int error; 1197 spa_t *spa; 1198 char *firstname; 1199 nvlist_t *suspended = NULL; 1200 1201 pair = nvlist_next_nvpair(snaps, NULL); 1202 if (pair == NULL) 1203 return (0); 1204 firstname = nvpair_name(pair); 1205 1206 error = spa_open(firstname, &spa, FTAG); 1207 if (error != 0) 1208 return (error); 1209 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1210 spa_close(spa, FTAG); 1211 1212 if (needsuspend) { 1213 suspended = fnvlist_alloc(); 1214 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1215 pair = nvlist_next_nvpair(snaps, pair)) { 1216 char fsname[MAXNAMELEN]; 1217 char *snapname = nvpair_name(pair); 1218 char *atp; 1219 void *cookie; 1220 1221 atp = strchr(snapname, '@'); 1222 if (atp == NULL) { 1223 error = SET_ERROR(EINVAL); 1224 break; 1225 } 1226 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1227 1228 error = zil_suspend(fsname, &cookie); 1229 if (error != 0) 1230 break; 1231 fnvlist_add_uint64(suspended, fsname, 1232 (uintptr_t)cookie); 1233 } 1234 } 1235 1236 ddsa.ddsa_snaps = snaps; 1237 ddsa.ddsa_props = props; 1238 ddsa.ddsa_errors = errors; 1239 1240 if (error == 0) { 1241 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1242 dsl_dataset_snapshot_sync, &ddsa, 1243 fnvlist_num_pairs(snaps) * 3); 1244 } 1245 1246 if (suspended != NULL) { 1247 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1248 pair = nvlist_next_nvpair(suspended, pair)) { 1249 zil_resume((void *)(uintptr_t) 1250 fnvpair_value_uint64(pair)); 1251 } 1252 fnvlist_free(suspended); 1253 } 1254 1255 return (error); 1256 } 1257 1258 typedef struct dsl_dataset_snapshot_tmp_arg { 1259 const char *ddsta_fsname; 1260 const char *ddsta_snapname; 1261 minor_t ddsta_cleanup_minor; 1262 const char *ddsta_htag; 1263 } dsl_dataset_snapshot_tmp_arg_t; 1264 1265 static int 1266 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1267 { 1268 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1269 dsl_pool_t *dp = dmu_tx_pool(tx); 1270 dsl_dataset_t *ds; 1271 int error; 1272 1273 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1274 if (error != 0) 1275 return (error); 1276 1277 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1278 tx, B_FALSE); 1279 if (error != 0) { 1280 dsl_dataset_rele(ds, FTAG); 1281 return (error); 1282 } 1283 1284 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1285 dsl_dataset_rele(ds, FTAG); 1286 return (SET_ERROR(ENOTSUP)); 1287 } 1288 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1289 B_TRUE, tx); 1290 if (error != 0) { 1291 dsl_dataset_rele(ds, FTAG); 1292 return (error); 1293 } 1294 1295 dsl_dataset_rele(ds, FTAG); 1296 return (0); 1297 } 1298 1299 static void 1300 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1301 { 1302 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1303 dsl_pool_t *dp = dmu_tx_pool(tx); 1304 dsl_dataset_t *ds; 1305 1306 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1307 1308 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1309 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1310 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1311 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1312 1313 dsl_dataset_rele(ds, FTAG); 1314 } 1315 1316 int 1317 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1318 minor_t cleanup_minor, const char *htag) 1319 { 1320 dsl_dataset_snapshot_tmp_arg_t ddsta; 1321 int error; 1322 spa_t *spa; 1323 boolean_t needsuspend; 1324 void *cookie; 1325 1326 ddsta.ddsta_fsname = fsname; 1327 ddsta.ddsta_snapname = snapname; 1328 ddsta.ddsta_cleanup_minor = cleanup_minor; 1329 ddsta.ddsta_htag = htag; 1330 1331 error = spa_open(fsname, &spa, FTAG); 1332 if (error != 0) 1333 return (error); 1334 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1335 spa_close(spa, FTAG); 1336 1337 if (needsuspend) { 1338 error = zil_suspend(fsname, &cookie); 1339 if (error != 0) 1340 return (error); 1341 } 1342 1343 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1344 dsl_dataset_snapshot_tmp_sync, &ddsta, 3); 1345 1346 if (needsuspend) 1347 zil_resume(cookie); 1348 return (error); 1349 } 1350 1351 1352 void 1353 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1354 { 1355 ASSERT(dmu_tx_is_syncing(tx)); 1356 ASSERT(ds->ds_objset != NULL); 1357 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1358 1359 /* 1360 * in case we had to change ds_fsid_guid when we opened it, 1361 * sync it out now. 1362 */ 1363 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1364 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1365 1366 dmu_objset_sync(ds->ds_objset, zio, tx); 1367 } 1368 1369 static void 1370 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1371 { 1372 uint64_t count = 0; 1373 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1374 zap_cursor_t zc; 1375 zap_attribute_t za; 1376 nvlist_t *propval = fnvlist_alloc(); 1377 nvlist_t *val = fnvlist_alloc(); 1378 1379 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1380 1381 /* 1382 * There may be missing entries in ds_next_clones_obj 1383 * due to a bug in a previous version of the code. 1384 * Only trust it if it has the right number of entries. 1385 */ 1386 if (ds->ds_phys->ds_next_clones_obj != 0) { 1387 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj, 1388 &count)); 1389 } 1390 if (count != ds->ds_phys->ds_num_children - 1) 1391 goto fail; 1392 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj); 1393 zap_cursor_retrieve(&zc, &za) == 0; 1394 zap_cursor_advance(&zc)) { 1395 dsl_dataset_t *clone; 1396 char buf[ZFS_MAXNAMELEN]; 1397 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1398 za.za_first_integer, FTAG, &clone)); 1399 dsl_dir_name(clone->ds_dir, buf); 1400 fnvlist_add_boolean(val, buf); 1401 dsl_dataset_rele(clone, FTAG); 1402 } 1403 zap_cursor_fini(&zc); 1404 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1405 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1406 fail: 1407 nvlist_free(val); 1408 nvlist_free(propval); 1409 } 1410 1411 void 1412 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1413 { 1414 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1415 uint64_t refd, avail, uobjs, aobjs, ratio; 1416 1417 ASSERT(dsl_pool_config_held(dp)); 1418 1419 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1420 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1421 ds->ds_phys->ds_compressed_bytes); 1422 1423 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1424 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1425 ds->ds_phys->ds_uncompressed_bytes); 1426 1427 if (dsl_dataset_is_snapshot(ds)) { 1428 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1429 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1430 ds->ds_phys->ds_unique_bytes); 1431 get_clones_stat(ds, nv); 1432 } else { 1433 dsl_dir_stats(ds->ds_dir, nv); 1434 } 1435 1436 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1437 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1438 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1439 1440 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1441 ds->ds_phys->ds_creation_time); 1442 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1443 ds->ds_phys->ds_creation_txg); 1444 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1445 ds->ds_quota); 1446 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1447 ds->ds_reserved); 1448 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1449 ds->ds_phys->ds_guid); 1450 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1451 ds->ds_phys->ds_unique_bytes); 1452 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1453 ds->ds_object); 1454 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1455 ds->ds_userrefs); 1456 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1457 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1458 1459 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1460 uint64_t written, comp, uncomp; 1461 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1462 dsl_dataset_t *prev; 1463 1464 int err = dsl_dataset_hold_obj(dp, 1465 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev); 1466 if (err == 0) { 1467 err = dsl_dataset_space_written(prev, ds, &written, 1468 &comp, &uncomp); 1469 dsl_dataset_rele(prev, FTAG); 1470 if (err == 0) { 1471 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1472 written); 1473 } 1474 } 1475 } 1476 } 1477 1478 void 1479 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1480 { 1481 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1482 ASSERT(dsl_pool_config_held(dp)); 1483 1484 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1485 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1486 stat->dds_guid = ds->ds_phys->ds_guid; 1487 stat->dds_origin[0] = '\0'; 1488 if (dsl_dataset_is_snapshot(ds)) { 1489 stat->dds_is_snapshot = B_TRUE; 1490 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1491 } else { 1492 stat->dds_is_snapshot = B_FALSE; 1493 stat->dds_num_clones = 0; 1494 1495 if (dsl_dir_is_clone(ds->ds_dir)) { 1496 dsl_dataset_t *ods; 1497 1498 VERIFY0(dsl_dataset_hold_obj(dp, 1499 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1500 dsl_dataset_name(ods, stat->dds_origin); 1501 dsl_dataset_rele(ods, FTAG); 1502 } 1503 } 1504 } 1505 1506 uint64_t 1507 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1508 { 1509 return (ds->ds_fsid_guid); 1510 } 1511 1512 void 1513 dsl_dataset_space(dsl_dataset_t *ds, 1514 uint64_t *refdbytesp, uint64_t *availbytesp, 1515 uint64_t *usedobjsp, uint64_t *availobjsp) 1516 { 1517 *refdbytesp = ds->ds_phys->ds_referenced_bytes; 1518 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1519 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1520 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1521 if (ds->ds_quota != 0) { 1522 /* 1523 * Adjust available bytes according to refquota 1524 */ 1525 if (*refdbytesp < ds->ds_quota) 1526 *availbytesp = MIN(*availbytesp, 1527 ds->ds_quota - *refdbytesp); 1528 else 1529 *availbytesp = 0; 1530 } 1531 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1532 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1533 } 1534 1535 boolean_t 1536 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1537 { 1538 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1539 1540 ASSERT(dsl_pool_config_held(dp)); 1541 if (snap == NULL) 1542 return (B_FALSE); 1543 if (ds->ds_phys->ds_bp.blk_birth > 1544 snap->ds_phys->ds_creation_txg) { 1545 objset_t *os, *os_snap; 1546 /* 1547 * It may be that only the ZIL differs, because it was 1548 * reset in the head. Don't count that as being 1549 * modified. 1550 */ 1551 if (dmu_objset_from_ds(ds, &os) != 0) 1552 return (B_TRUE); 1553 if (dmu_objset_from_ds(snap, &os_snap) != 0) 1554 return (B_TRUE); 1555 return (bcmp(&os->os_phys->os_meta_dnode, 1556 &os_snap->os_phys->os_meta_dnode, 1557 sizeof (os->os_phys->os_meta_dnode)) != 0); 1558 } 1559 return (B_FALSE); 1560 } 1561 1562 typedef struct dsl_dataset_rename_snapshot_arg { 1563 const char *ddrsa_fsname; 1564 const char *ddrsa_oldsnapname; 1565 const char *ddrsa_newsnapname; 1566 boolean_t ddrsa_recursive; 1567 dmu_tx_t *ddrsa_tx; 1568 } dsl_dataset_rename_snapshot_arg_t; 1569 1570 /* ARGSUSED */ 1571 static int 1572 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1573 dsl_dataset_t *hds, void *arg) 1574 { 1575 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1576 int error; 1577 uint64_t val; 1578 1579 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1580 if (error != 0) { 1581 /* ignore nonexistent snapshots */ 1582 return (error == ENOENT ? 0 : error); 1583 } 1584 1585 /* new name should not exist */ 1586 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 1587 if (error == 0) 1588 error = SET_ERROR(EEXIST); 1589 else if (error == ENOENT) 1590 error = 0; 1591 1592 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1593 if (dsl_dir_namelen(hds->ds_dir) + 1 + 1594 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN) 1595 error = SET_ERROR(ENAMETOOLONG); 1596 1597 return (error); 1598 } 1599 1600 static int 1601 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 1602 { 1603 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1604 dsl_pool_t *dp = dmu_tx_pool(tx); 1605 dsl_dataset_t *hds; 1606 int error; 1607 1608 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 1609 if (error != 0) 1610 return (error); 1611 1612 if (ddrsa->ddrsa_recursive) { 1613 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1614 dsl_dataset_rename_snapshot_check_impl, ddrsa, 1615 DS_FIND_CHILDREN); 1616 } else { 1617 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 1618 } 1619 dsl_dataset_rele(hds, FTAG); 1620 return (error); 1621 } 1622 1623 static int 1624 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 1625 dsl_dataset_t *hds, void *arg) 1626 { 1627 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1628 dsl_dataset_t *ds; 1629 uint64_t val; 1630 dmu_tx_t *tx = ddrsa->ddrsa_tx; 1631 int error; 1632 1633 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1634 ASSERT(error == 0 || error == ENOENT); 1635 if (error == ENOENT) { 1636 /* ignore nonexistent snapshots */ 1637 return (0); 1638 } 1639 1640 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 1641 1642 /* log before we change the name */ 1643 spa_history_log_internal_ds(ds, "rename", tx, 1644 "-> @%s", ddrsa->ddrsa_newsnapname); 1645 1646 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx)); 1647 mutex_enter(&ds->ds_lock); 1648 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 1649 mutex_exit(&ds->ds_lock); 1650 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj, 1651 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 1652 1653 dsl_dataset_rele(ds, FTAG); 1654 return (0); 1655 } 1656 1657 static void 1658 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 1659 { 1660 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1661 dsl_pool_t *dp = dmu_tx_pool(tx); 1662 dsl_dataset_t *hds; 1663 1664 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 1665 ddrsa->ddrsa_tx = tx; 1666 if (ddrsa->ddrsa_recursive) { 1667 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 1668 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 1669 DS_FIND_CHILDREN)); 1670 } else { 1671 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 1672 } 1673 dsl_dataset_rele(hds, FTAG); 1674 } 1675 1676 int 1677 dsl_dataset_rename_snapshot(const char *fsname, 1678 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 1679 { 1680 dsl_dataset_rename_snapshot_arg_t ddrsa; 1681 1682 ddrsa.ddrsa_fsname = fsname; 1683 ddrsa.ddrsa_oldsnapname = oldsnapname; 1684 ddrsa.ddrsa_newsnapname = newsnapname; 1685 ddrsa.ddrsa_recursive = recursive; 1686 1687 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 1688 dsl_dataset_rename_snapshot_sync, &ddrsa, 1)); 1689 } 1690 1691 /* 1692 * If we're doing an ownership handoff, we need to make sure that there is 1693 * only one long hold on the dataset. We're not allowed to change anything here 1694 * so we don't permanently release the long hold or regular hold here. We want 1695 * to do this only when syncing to avoid the dataset unexpectedly going away 1696 * when we release the long hold. 1697 */ 1698 static int 1699 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 1700 { 1701 boolean_t held; 1702 1703 if (!dmu_tx_is_syncing(tx)) 1704 return (0); 1705 1706 if (owner != NULL) { 1707 VERIFY3P(ds->ds_owner, ==, owner); 1708 dsl_dataset_long_rele(ds, owner); 1709 } 1710 1711 held = dsl_dataset_long_held(ds); 1712 1713 if (owner != NULL) 1714 dsl_dataset_long_hold(ds, owner); 1715 1716 if (held) 1717 return (SET_ERROR(EBUSY)); 1718 1719 return (0); 1720 } 1721 1722 typedef struct dsl_dataset_rollback_arg { 1723 const char *ddra_fsname; 1724 void *ddra_owner; 1725 } dsl_dataset_rollback_arg_t; 1726 1727 static int 1728 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 1729 { 1730 dsl_dataset_rollback_arg_t *ddra = arg; 1731 dsl_pool_t *dp = dmu_tx_pool(tx); 1732 dsl_dataset_t *ds; 1733 int64_t unused_refres_delta; 1734 int error; 1735 1736 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 1737 if (error != 0) 1738 return (error); 1739 1740 /* must not be a snapshot */ 1741 if (dsl_dataset_is_snapshot(ds)) { 1742 dsl_dataset_rele(ds, FTAG); 1743 return (SET_ERROR(EINVAL)); 1744 } 1745 1746 /* must have a most recent snapshot */ 1747 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) { 1748 dsl_dataset_rele(ds, FTAG); 1749 return (SET_ERROR(EINVAL)); 1750 } 1751 1752 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 1753 if (error != 0) { 1754 dsl_dataset_rele(ds, FTAG); 1755 return (error); 1756 } 1757 1758 /* 1759 * Check if the snap we are rolling back to uses more than 1760 * the refquota. 1761 */ 1762 if (ds->ds_quota != 0 && 1763 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) { 1764 dsl_dataset_rele(ds, FTAG); 1765 return (SET_ERROR(EDQUOT)); 1766 } 1767 1768 /* 1769 * When we do the clone swap, we will temporarily use more space 1770 * due to the refreservation (the head will no longer have any 1771 * unique space, so the entire amount of the refreservation will need 1772 * to be free). We will immediately destroy the clone, freeing 1773 * this space, but the freeing happens over many txg's. 1774 */ 1775 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 1776 ds->ds_phys->ds_unique_bytes); 1777 1778 if (unused_refres_delta > 0 && 1779 unused_refres_delta > 1780 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 1781 dsl_dataset_rele(ds, FTAG); 1782 return (SET_ERROR(ENOSPC)); 1783 } 1784 1785 dsl_dataset_rele(ds, FTAG); 1786 return (0); 1787 } 1788 1789 static void 1790 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 1791 { 1792 dsl_dataset_rollback_arg_t *ddra = arg; 1793 dsl_pool_t *dp = dmu_tx_pool(tx); 1794 dsl_dataset_t *ds, *clone; 1795 uint64_t cloneobj; 1796 1797 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 1798 1799 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 1800 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 1801 1802 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 1803 1804 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 1805 dsl_dataset_zero_zil(ds, tx); 1806 1807 dsl_destroy_head_sync_impl(clone, tx); 1808 1809 dsl_dataset_rele(clone, FTAG); 1810 dsl_dataset_rele(ds, FTAG); 1811 } 1812 1813 /* 1814 * If owner != NULL: 1815 * 1816 * - The existing dataset MUST be owned by the specified owner at entry 1817 * - Upon return, dataset will still be held by the same owner, whether we 1818 * succeed or not. 1819 * 1820 * This mode is required any time the existing filesystem is mounted. See 1821 * notes above zfs_suspend_fs() for further details. 1822 */ 1823 int 1824 dsl_dataset_rollback(const char *fsname, void *owner) 1825 { 1826 dsl_dataset_rollback_arg_t ddra; 1827 1828 ddra.ddra_fsname = fsname; 1829 ddra.ddra_owner = owner; 1830 1831 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 1832 dsl_dataset_rollback_sync, (void *)&ddra, 1)); 1833 } 1834 1835 struct promotenode { 1836 list_node_t link; 1837 dsl_dataset_t *ds; 1838 }; 1839 1840 typedef struct dsl_dataset_promote_arg { 1841 const char *ddpa_clonename; 1842 dsl_dataset_t *ddpa_clone; 1843 list_t shared_snaps, origin_snaps, clone_snaps; 1844 dsl_dataset_t *origin_origin; /* origin of the origin */ 1845 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 1846 char *err_ds; 1847 } dsl_dataset_promote_arg_t; 1848 1849 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 1850 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 1851 void *tag); 1852 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 1853 1854 static int 1855 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 1856 { 1857 dsl_dataset_promote_arg_t *ddpa = arg; 1858 dsl_pool_t *dp = dmu_tx_pool(tx); 1859 dsl_dataset_t *hds; 1860 struct promotenode *snap; 1861 dsl_dataset_t *origin_ds; 1862 int err; 1863 uint64_t unused; 1864 1865 err = promote_hold(ddpa, dp, FTAG); 1866 if (err != 0) 1867 return (err); 1868 1869 hds = ddpa->ddpa_clone; 1870 1871 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) { 1872 promote_rele(ddpa, FTAG); 1873 return (SET_ERROR(EXDEV)); 1874 } 1875 1876 /* 1877 * Compute and check the amount of space to transfer. Since this is 1878 * so expensive, don't do the preliminary check. 1879 */ 1880 if (!dmu_tx_is_syncing(tx)) { 1881 promote_rele(ddpa, FTAG); 1882 return (0); 1883 } 1884 1885 snap = list_head(&ddpa->shared_snaps); 1886 origin_ds = snap->ds; 1887 1888 /* compute origin's new unique space */ 1889 snap = list_tail(&ddpa->clone_snaps); 1890 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 1891 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 1892 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, 1893 &ddpa->unique, &unused, &unused); 1894 1895 /* 1896 * Walk the snapshots that we are moving 1897 * 1898 * Compute space to transfer. Consider the incremental changes 1899 * to used by each snapshot: 1900 * (my used) = (prev's used) + (blocks born) - (blocks killed) 1901 * So each snapshot gave birth to: 1902 * (blocks born) = (my used) - (prev's used) + (blocks killed) 1903 * So a sequence would look like: 1904 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 1905 * Which simplifies to: 1906 * uN + kN + kN-1 + ... + k1 + k0 1907 * Note however, if we stop before we reach the ORIGIN we get: 1908 * uN + kN + kN-1 + ... + kM - uM-1 1909 */ 1910 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes; 1911 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes; 1912 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 1913 for (snap = list_head(&ddpa->shared_snaps); snap; 1914 snap = list_next(&ddpa->shared_snaps, snap)) { 1915 uint64_t val, dlused, dlcomp, dluncomp; 1916 dsl_dataset_t *ds = snap->ds; 1917 1918 /* 1919 * If there are long holds, we won't be able to evict 1920 * the objset. 1921 */ 1922 if (dsl_dataset_long_held(ds)) { 1923 err = SET_ERROR(EBUSY); 1924 goto out; 1925 } 1926 1927 /* Check that the snapshot name does not conflict */ 1928 VERIFY0(dsl_dataset_get_snapname(ds)); 1929 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 1930 if (err == 0) { 1931 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 1932 err = SET_ERROR(EEXIST); 1933 goto out; 1934 } 1935 if (err != ENOENT) 1936 goto out; 1937 1938 /* The very first snapshot does not have a deadlist */ 1939 if (ds->ds_phys->ds_prev_snap_obj == 0) 1940 continue; 1941 1942 dsl_deadlist_space(&ds->ds_deadlist, 1943 &dlused, &dlcomp, &dluncomp); 1944 ddpa->used += dlused; 1945 ddpa->comp += dlcomp; 1946 ddpa->uncomp += dluncomp; 1947 } 1948 1949 /* 1950 * If we are a clone of a clone then we never reached ORIGIN, 1951 * so we need to subtract out the clone origin's used space. 1952 */ 1953 if (ddpa->origin_origin) { 1954 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes; 1955 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes; 1956 ddpa->uncomp -= 1957 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes; 1958 } 1959 1960 /* Check that there is enough space here */ 1961 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 1962 ddpa->used); 1963 if (err != 0) 1964 goto out; 1965 1966 /* 1967 * Compute the amounts of space that will be used by snapshots 1968 * after the promotion (for both origin and clone). For each, 1969 * it is the amount of space that will be on all of their 1970 * deadlists (that was not born before their new origin). 1971 */ 1972 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 1973 uint64_t space; 1974 1975 /* 1976 * Note, typically this will not be a clone of a clone, 1977 * so dd_origin_txg will be < TXG_INITIAL, so 1978 * these snaplist_space() -> dsl_deadlist_space_range() 1979 * calls will be fast because they do not have to 1980 * iterate over all bps. 1981 */ 1982 snap = list_head(&ddpa->origin_snaps); 1983 err = snaplist_space(&ddpa->shared_snaps, 1984 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 1985 if (err != 0) 1986 goto out; 1987 1988 err = snaplist_space(&ddpa->clone_snaps, 1989 snap->ds->ds_dir->dd_origin_txg, &space); 1990 if (err != 0) 1991 goto out; 1992 ddpa->cloneusedsnap += space; 1993 } 1994 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 1995 err = snaplist_space(&ddpa->origin_snaps, 1996 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap); 1997 if (err != 0) 1998 goto out; 1999 } 2000 2001 out: 2002 promote_rele(ddpa, FTAG); 2003 return (err); 2004 } 2005 2006 static void 2007 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2008 { 2009 dsl_dataset_promote_arg_t *ddpa = arg; 2010 dsl_pool_t *dp = dmu_tx_pool(tx); 2011 dsl_dataset_t *hds; 2012 struct promotenode *snap; 2013 dsl_dataset_t *origin_ds; 2014 dsl_dataset_t *origin_head; 2015 dsl_dir_t *dd; 2016 dsl_dir_t *odd = NULL; 2017 uint64_t oldnext_obj; 2018 int64_t delta; 2019 2020 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2021 hds = ddpa->ddpa_clone; 2022 2023 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE); 2024 2025 snap = list_head(&ddpa->shared_snaps); 2026 origin_ds = snap->ds; 2027 dd = hds->ds_dir; 2028 2029 snap = list_head(&ddpa->origin_snaps); 2030 origin_head = snap->ds; 2031 2032 /* 2033 * We need to explicitly open odd, since origin_ds's dd will be 2034 * changing. 2035 */ 2036 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2037 NULL, FTAG, &odd)); 2038 2039 /* change origin's next snap */ 2040 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2041 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2042 snap = list_tail(&ddpa->clone_snaps); 2043 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2044 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2045 2046 /* change the origin's next clone */ 2047 if (origin_ds->ds_phys->ds_next_clones_obj) { 2048 dsl_dataset_remove_from_next_clones(origin_ds, 2049 snap->ds->ds_object, tx); 2050 VERIFY0(zap_add_int(dp->dp_meta_objset, 2051 origin_ds->ds_phys->ds_next_clones_obj, 2052 oldnext_obj, tx)); 2053 } 2054 2055 /* change origin */ 2056 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2057 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2058 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2059 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2060 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2061 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2062 origin_head->ds_dir->dd_origin_txg = 2063 origin_ds->ds_phys->ds_creation_txg; 2064 2065 /* change dd_clone entries */ 2066 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2067 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2068 odd->dd_phys->dd_clones, hds->ds_object, tx)); 2069 VERIFY0(zap_add_int(dp->dp_meta_objset, 2070 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2071 hds->ds_object, tx)); 2072 2073 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2074 ddpa->origin_origin->ds_dir->dd_phys->dd_clones, 2075 origin_head->ds_object, tx)); 2076 if (dd->dd_phys->dd_clones == 0) { 2077 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset, 2078 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 2079 } 2080 VERIFY0(zap_add_int(dp->dp_meta_objset, 2081 dd->dd_phys->dd_clones, origin_head->ds_object, tx)); 2082 } 2083 2084 /* move snapshots to this dir */ 2085 for (snap = list_head(&ddpa->shared_snaps); snap; 2086 snap = list_next(&ddpa->shared_snaps, snap)) { 2087 dsl_dataset_t *ds = snap->ds; 2088 2089 /* 2090 * Property callbacks are registered to a particular 2091 * dsl_dir. Since ours is changing, evict the objset 2092 * so that they will be unregistered from the old dsl_dir. 2093 */ 2094 if (ds->ds_objset) { 2095 dmu_objset_evict(ds->ds_objset); 2096 ds->ds_objset = NULL; 2097 } 2098 2099 /* move snap name entry */ 2100 VERIFY0(dsl_dataset_get_snapname(ds)); 2101 VERIFY0(dsl_dataset_snap_remove(origin_head, 2102 ds->ds_snapname, tx)); 2103 VERIFY0(zap_add(dp->dp_meta_objset, 2104 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2105 8, 1, &ds->ds_object, tx)); 2106 2107 /* change containing dsl_dir */ 2108 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2109 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2110 ds->ds_phys->ds_dir_obj = dd->dd_object; 2111 ASSERT3P(ds->ds_dir, ==, odd); 2112 dsl_dir_rele(ds->ds_dir, ds); 2113 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2114 NULL, ds, &ds->ds_dir)); 2115 2116 /* move any clone references */ 2117 if (ds->ds_phys->ds_next_clones_obj && 2118 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2119 zap_cursor_t zc; 2120 zap_attribute_t za; 2121 2122 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2123 ds->ds_phys->ds_next_clones_obj); 2124 zap_cursor_retrieve(&zc, &za) == 0; 2125 zap_cursor_advance(&zc)) { 2126 dsl_dataset_t *cnds; 2127 uint64_t o; 2128 2129 if (za.za_first_integer == oldnext_obj) { 2130 /* 2131 * We've already moved the 2132 * origin's reference. 2133 */ 2134 continue; 2135 } 2136 2137 VERIFY0(dsl_dataset_hold_obj(dp, 2138 za.za_first_integer, FTAG, &cnds)); 2139 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj; 2140 2141 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2142 odd->dd_phys->dd_clones, o, tx)); 2143 VERIFY0(zap_add_int(dp->dp_meta_objset, 2144 dd->dd_phys->dd_clones, o, tx)); 2145 dsl_dataset_rele(cnds, FTAG); 2146 } 2147 zap_cursor_fini(&zc); 2148 } 2149 2150 ASSERT(!dsl_prop_hascb(ds)); 2151 } 2152 2153 /* 2154 * Change space accounting. 2155 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2156 * both be valid, or both be 0 (resulting in delta == 0). This 2157 * is true for each of {clone,origin} independently. 2158 */ 2159 2160 delta = ddpa->cloneusedsnap - 2161 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2162 ASSERT3S(delta, >=, 0); 2163 ASSERT3U(ddpa->used, >=, delta); 2164 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2165 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2166 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2167 2168 delta = ddpa->originusedsnap - 2169 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2170 ASSERT3S(delta, <=, 0); 2171 ASSERT3U(ddpa->used, >=, -delta); 2172 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2173 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2174 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2175 2176 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique; 2177 2178 /* log history record */ 2179 spa_history_log_internal_ds(hds, "promote", tx, ""); 2180 2181 dsl_dir_rele(odd, FTAG); 2182 promote_rele(ddpa, FTAG); 2183 } 2184 2185 /* 2186 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2187 * (exclusive) and last_obj (inclusive). The list will be in reverse 2188 * order (last_obj will be the list_head()). If first_obj == 0, do all 2189 * snapshots back to this dataset's origin. 2190 */ 2191 static int 2192 snaplist_make(dsl_pool_t *dp, 2193 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2194 { 2195 uint64_t obj = last_obj; 2196 2197 list_create(l, sizeof (struct promotenode), 2198 offsetof(struct promotenode, link)); 2199 2200 while (obj != first_obj) { 2201 dsl_dataset_t *ds; 2202 struct promotenode *snap; 2203 int err; 2204 2205 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2206 ASSERT(err != ENOENT); 2207 if (err != 0) 2208 return (err); 2209 2210 if (first_obj == 0) 2211 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2212 2213 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2214 snap->ds = ds; 2215 list_insert_tail(l, snap); 2216 obj = ds->ds_phys->ds_prev_snap_obj; 2217 } 2218 2219 return (0); 2220 } 2221 2222 static int 2223 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2224 { 2225 struct promotenode *snap; 2226 2227 *spacep = 0; 2228 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2229 uint64_t used, comp, uncomp; 2230 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2231 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2232 *spacep += used; 2233 } 2234 return (0); 2235 } 2236 2237 static void 2238 snaplist_destroy(list_t *l, void *tag) 2239 { 2240 struct promotenode *snap; 2241 2242 if (l == NULL || !list_link_active(&l->list_head)) 2243 return; 2244 2245 while ((snap = list_tail(l)) != NULL) { 2246 list_remove(l, snap); 2247 dsl_dataset_rele(snap->ds, tag); 2248 kmem_free(snap, sizeof (*snap)); 2249 } 2250 list_destroy(l); 2251 } 2252 2253 static int 2254 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2255 { 2256 int error; 2257 dsl_dir_t *dd; 2258 struct promotenode *snap; 2259 2260 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2261 &ddpa->ddpa_clone); 2262 if (error != 0) 2263 return (error); 2264 dd = ddpa->ddpa_clone->ds_dir; 2265 2266 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) || 2267 !dsl_dir_is_clone(dd)) { 2268 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2269 return (SET_ERROR(EINVAL)); 2270 } 2271 2272 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj, 2273 &ddpa->shared_snaps, tag); 2274 if (error != 0) 2275 goto out; 2276 2277 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2278 &ddpa->clone_snaps, tag); 2279 if (error != 0) 2280 goto out; 2281 2282 snap = list_head(&ddpa->shared_snaps); 2283 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2284 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj, 2285 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, 2286 &ddpa->origin_snaps, tag); 2287 if (error != 0) 2288 goto out; 2289 2290 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) { 2291 error = dsl_dataset_hold_obj(dp, 2292 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2293 tag, &ddpa->origin_origin); 2294 if (error != 0) 2295 goto out; 2296 } 2297 out: 2298 if (error != 0) 2299 promote_rele(ddpa, tag); 2300 return (error); 2301 } 2302 2303 static void 2304 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2305 { 2306 snaplist_destroy(&ddpa->shared_snaps, tag); 2307 snaplist_destroy(&ddpa->clone_snaps, tag); 2308 snaplist_destroy(&ddpa->origin_snaps, tag); 2309 if (ddpa->origin_origin != NULL) 2310 dsl_dataset_rele(ddpa->origin_origin, tag); 2311 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2312 } 2313 2314 /* 2315 * Promote a clone. 2316 * 2317 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2318 * in with the name. (It must be at least MAXNAMELEN bytes long.) 2319 */ 2320 int 2321 dsl_dataset_promote(const char *name, char *conflsnap) 2322 { 2323 dsl_dataset_promote_arg_t ddpa = { 0 }; 2324 uint64_t numsnaps; 2325 int error; 2326 objset_t *os; 2327 2328 /* 2329 * We will modify space proportional to the number of 2330 * snapshots. Compute numsnaps. 2331 */ 2332 error = dmu_objset_hold(name, FTAG, &os); 2333 if (error != 0) 2334 return (error); 2335 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2336 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps); 2337 dmu_objset_rele(os, FTAG); 2338 if (error != 0) 2339 return (error); 2340 2341 ddpa.ddpa_clonename = name; 2342 ddpa.err_ds = conflsnap; 2343 2344 return (dsl_sync_task(name, dsl_dataset_promote_check, 2345 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps)); 2346 } 2347 2348 int 2349 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2350 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2351 { 2352 int64_t unused_refres_delta; 2353 2354 /* they should both be heads */ 2355 if (dsl_dataset_is_snapshot(clone) || 2356 dsl_dataset_is_snapshot(origin_head)) 2357 return (SET_ERROR(EINVAL)); 2358 2359 /* if we are not forcing, the branch point should be just before them */ 2360 if (!force && clone->ds_prev != origin_head->ds_prev) 2361 return (SET_ERROR(EINVAL)); 2362 2363 /* clone should be the clone (unless they are unrelated) */ 2364 if (clone->ds_prev != NULL && 2365 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2366 origin_head->ds_dir != clone->ds_prev->ds_dir) 2367 return (SET_ERROR(EINVAL)); 2368 2369 /* the clone should be a child of the origin */ 2370 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2371 return (SET_ERROR(EINVAL)); 2372 2373 /* origin_head shouldn't be modified unless 'force' */ 2374 if (!force && 2375 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2376 return (SET_ERROR(ETXTBSY)); 2377 2378 /* origin_head should have no long holds (e.g. is not mounted) */ 2379 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2380 return (SET_ERROR(EBUSY)); 2381 2382 /* check amount of any unconsumed refreservation */ 2383 unused_refres_delta = 2384 (int64_t)MIN(origin_head->ds_reserved, 2385 origin_head->ds_phys->ds_unique_bytes) - 2386 (int64_t)MIN(origin_head->ds_reserved, 2387 clone->ds_phys->ds_unique_bytes); 2388 2389 if (unused_refres_delta > 0 && 2390 unused_refres_delta > 2391 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2392 return (SET_ERROR(ENOSPC)); 2393 2394 /* clone can't be over the head's refquota */ 2395 if (origin_head->ds_quota != 0 && 2396 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota) 2397 return (SET_ERROR(EDQUOT)); 2398 2399 return (0); 2400 } 2401 2402 void 2403 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2404 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2405 { 2406 dsl_pool_t *dp = dmu_tx_pool(tx); 2407 int64_t unused_refres_delta; 2408 2409 ASSERT(clone->ds_reserved == 0); 2410 ASSERT(origin_head->ds_quota == 0 || 2411 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota); 2412 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2413 2414 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2415 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2416 2417 if (clone->ds_objset != NULL) { 2418 dmu_objset_evict(clone->ds_objset); 2419 clone->ds_objset = NULL; 2420 } 2421 2422 if (origin_head->ds_objset != NULL) { 2423 dmu_objset_evict(origin_head->ds_objset); 2424 origin_head->ds_objset = NULL; 2425 } 2426 2427 unused_refres_delta = 2428 (int64_t)MIN(origin_head->ds_reserved, 2429 origin_head->ds_phys->ds_unique_bytes) - 2430 (int64_t)MIN(origin_head->ds_reserved, 2431 clone->ds_phys->ds_unique_bytes); 2432 2433 /* 2434 * Reset origin's unique bytes, if it exists. 2435 */ 2436 if (clone->ds_prev) { 2437 dsl_dataset_t *origin = clone->ds_prev; 2438 uint64_t comp, uncomp; 2439 2440 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2441 dsl_deadlist_space_range(&clone->ds_deadlist, 2442 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2443 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp); 2444 } 2445 2446 /* swap blkptrs */ 2447 { 2448 blkptr_t tmp; 2449 tmp = origin_head->ds_phys->ds_bp; 2450 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp; 2451 clone->ds_phys->ds_bp = tmp; 2452 } 2453 2454 /* set dd_*_bytes */ 2455 { 2456 int64_t dused, dcomp, duncomp; 2457 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2458 uint64_t odl_used, odl_comp, odl_uncomp; 2459 2460 ASSERT3U(clone->ds_dir->dd_phys-> 2461 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2462 2463 dsl_deadlist_space(&clone->ds_deadlist, 2464 &cdl_used, &cdl_comp, &cdl_uncomp); 2465 dsl_deadlist_space(&origin_head->ds_deadlist, 2466 &odl_used, &odl_comp, &odl_uncomp); 2467 2468 dused = clone->ds_phys->ds_referenced_bytes + cdl_used - 2469 (origin_head->ds_phys->ds_referenced_bytes + odl_used); 2470 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp - 2471 (origin_head->ds_phys->ds_compressed_bytes + odl_comp); 2472 duncomp = clone->ds_phys->ds_uncompressed_bytes + 2473 cdl_uncomp - 2474 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2475 2476 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 2477 dused, dcomp, duncomp, tx); 2478 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 2479 -dused, -dcomp, -duncomp, tx); 2480 2481 /* 2482 * The difference in the space used by snapshots is the 2483 * difference in snapshot space due to the head's 2484 * deadlist (since that's the only thing that's 2485 * changing that affects the snapused). 2486 */ 2487 dsl_deadlist_space_range(&clone->ds_deadlist, 2488 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2489 &cdl_used, &cdl_comp, &cdl_uncomp); 2490 dsl_deadlist_space_range(&origin_head->ds_deadlist, 2491 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 2492 &odl_used, &odl_comp, &odl_uncomp); 2493 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 2494 DD_USED_HEAD, DD_USED_SNAP, tx); 2495 } 2496 2497 /* swap ds_*_bytes */ 2498 SWITCH64(origin_head->ds_phys->ds_referenced_bytes, 2499 clone->ds_phys->ds_referenced_bytes); 2500 SWITCH64(origin_head->ds_phys->ds_compressed_bytes, 2501 clone->ds_phys->ds_compressed_bytes); 2502 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes, 2503 clone->ds_phys->ds_uncompressed_bytes); 2504 SWITCH64(origin_head->ds_phys->ds_unique_bytes, 2505 clone->ds_phys->ds_unique_bytes); 2506 2507 /* apply any parent delta for change in unconsumed refreservation */ 2508 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 2509 unused_refres_delta, 0, 0, tx); 2510 2511 /* 2512 * Swap deadlists. 2513 */ 2514 dsl_deadlist_close(&clone->ds_deadlist); 2515 dsl_deadlist_close(&origin_head->ds_deadlist); 2516 SWITCH64(origin_head->ds_phys->ds_deadlist_obj, 2517 clone->ds_phys->ds_deadlist_obj); 2518 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 2519 clone->ds_phys->ds_deadlist_obj); 2520 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 2521 origin_head->ds_phys->ds_deadlist_obj); 2522 2523 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 2524 2525 spa_history_log_internal_ds(clone, "clone swap", tx, 2526 "parent=%s", origin_head->ds_dir->dd_myname); 2527 } 2528 2529 /* 2530 * Given a pool name and a dataset object number in that pool, 2531 * return the name of that dataset. 2532 */ 2533 int 2534 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2535 { 2536 dsl_pool_t *dp; 2537 dsl_dataset_t *ds; 2538 int error; 2539 2540 error = dsl_pool_hold(pname, FTAG, &dp); 2541 if (error != 0) 2542 return (error); 2543 2544 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 2545 if (error == 0) { 2546 dsl_dataset_name(ds, buf); 2547 dsl_dataset_rele(ds, FTAG); 2548 } 2549 dsl_pool_rele(dp, FTAG); 2550 2551 return (error); 2552 } 2553 2554 int 2555 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2556 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2557 { 2558 int error = 0; 2559 2560 ASSERT3S(asize, >, 0); 2561 2562 /* 2563 * *ref_rsrv is the portion of asize that will come from any 2564 * unconsumed refreservation space. 2565 */ 2566 *ref_rsrv = 0; 2567 2568 mutex_enter(&ds->ds_lock); 2569 /* 2570 * Make a space adjustment for reserved bytes. 2571 */ 2572 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2573 ASSERT3U(*used, >=, 2574 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2575 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2576 *ref_rsrv = 2577 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2578 } 2579 2580 if (!check_quota || ds->ds_quota == 0) { 2581 mutex_exit(&ds->ds_lock); 2582 return (0); 2583 } 2584 /* 2585 * If they are requesting more space, and our current estimate 2586 * is over quota, they get to try again unless the actual 2587 * on-disk is over quota and there are no pending changes (which 2588 * may free up space for us). 2589 */ 2590 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) { 2591 if (inflight > 0 || 2592 ds->ds_phys->ds_referenced_bytes < ds->ds_quota) 2593 error = SET_ERROR(ERESTART); 2594 else 2595 error = SET_ERROR(EDQUOT); 2596 } 2597 mutex_exit(&ds->ds_lock); 2598 2599 return (error); 2600 } 2601 2602 typedef struct dsl_dataset_set_qr_arg { 2603 const char *ddsqra_name; 2604 zprop_source_t ddsqra_source; 2605 uint64_t ddsqra_value; 2606 } dsl_dataset_set_qr_arg_t; 2607 2608 2609 /* ARGSUSED */ 2610 static int 2611 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 2612 { 2613 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2614 dsl_pool_t *dp = dmu_tx_pool(tx); 2615 dsl_dataset_t *ds; 2616 int error; 2617 uint64_t newval; 2618 2619 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 2620 return (SET_ERROR(ENOTSUP)); 2621 2622 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2623 if (error != 0) 2624 return (error); 2625 2626 if (dsl_dataset_is_snapshot(ds)) { 2627 dsl_dataset_rele(ds, FTAG); 2628 return (SET_ERROR(EINVAL)); 2629 } 2630 2631 error = dsl_prop_predict(ds->ds_dir, 2632 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2633 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2634 if (error != 0) { 2635 dsl_dataset_rele(ds, FTAG); 2636 return (error); 2637 } 2638 2639 if (newval == 0) { 2640 dsl_dataset_rele(ds, FTAG); 2641 return (0); 2642 } 2643 2644 if (newval < ds->ds_phys->ds_referenced_bytes || 2645 newval < ds->ds_reserved) { 2646 dsl_dataset_rele(ds, FTAG); 2647 return (SET_ERROR(ENOSPC)); 2648 } 2649 2650 dsl_dataset_rele(ds, FTAG); 2651 return (0); 2652 } 2653 2654 static void 2655 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 2656 { 2657 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2658 dsl_pool_t *dp = dmu_tx_pool(tx); 2659 dsl_dataset_t *ds; 2660 uint64_t newval; 2661 2662 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2663 2664 dsl_prop_set_sync_impl(ds, 2665 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 2666 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 2667 &ddsqra->ddsqra_value, tx); 2668 2669 VERIFY0(dsl_prop_get_int_ds(ds, 2670 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 2671 2672 if (ds->ds_quota != newval) { 2673 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2674 ds->ds_quota = newval; 2675 } 2676 dsl_dataset_rele(ds, FTAG); 2677 } 2678 2679 int 2680 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 2681 uint64_t refquota) 2682 { 2683 dsl_dataset_set_qr_arg_t ddsqra; 2684 2685 ddsqra.ddsqra_name = dsname; 2686 ddsqra.ddsqra_source = source; 2687 ddsqra.ddsqra_value = refquota; 2688 2689 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 2690 dsl_dataset_set_refquota_sync, &ddsqra, 0)); 2691 } 2692 2693 static int 2694 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 2695 { 2696 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2697 dsl_pool_t *dp = dmu_tx_pool(tx); 2698 dsl_dataset_t *ds; 2699 int error; 2700 uint64_t newval, unique; 2701 2702 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 2703 return (SET_ERROR(ENOTSUP)); 2704 2705 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 2706 if (error != 0) 2707 return (error); 2708 2709 if (dsl_dataset_is_snapshot(ds)) { 2710 dsl_dataset_rele(ds, FTAG); 2711 return (SET_ERROR(EINVAL)); 2712 } 2713 2714 error = dsl_prop_predict(ds->ds_dir, 2715 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2716 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 2717 if (error != 0) { 2718 dsl_dataset_rele(ds, FTAG); 2719 return (error); 2720 } 2721 2722 /* 2723 * If we are doing the preliminary check in open context, the 2724 * space estimates may be inaccurate. 2725 */ 2726 if (!dmu_tx_is_syncing(tx)) { 2727 dsl_dataset_rele(ds, FTAG); 2728 return (0); 2729 } 2730 2731 mutex_enter(&ds->ds_lock); 2732 if (!DS_UNIQUE_IS_ACCURATE(ds)) 2733 dsl_dataset_recalc_head_uniq(ds); 2734 unique = ds->ds_phys->ds_unique_bytes; 2735 mutex_exit(&ds->ds_lock); 2736 2737 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 2738 uint64_t delta = MAX(unique, newval) - 2739 MAX(unique, ds->ds_reserved); 2740 2741 if (delta > 2742 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 2743 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 2744 dsl_dataset_rele(ds, FTAG); 2745 return (SET_ERROR(ENOSPC)); 2746 } 2747 } 2748 2749 dsl_dataset_rele(ds, FTAG); 2750 return (0); 2751 } 2752 2753 void 2754 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 2755 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 2756 { 2757 uint64_t newval; 2758 uint64_t unique; 2759 int64_t delta; 2760 2761 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 2762 source, sizeof (value), 1, &value, tx); 2763 2764 VERIFY0(dsl_prop_get_int_ds(ds, 2765 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 2766 2767 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2768 mutex_enter(&ds->ds_dir->dd_lock); 2769 mutex_enter(&ds->ds_lock); 2770 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 2771 unique = ds->ds_phys->ds_unique_bytes; 2772 delta = MAX(0, (int64_t)(newval - unique)) - 2773 MAX(0, (int64_t)(ds->ds_reserved - unique)); 2774 ds->ds_reserved = newval; 2775 mutex_exit(&ds->ds_lock); 2776 2777 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 2778 mutex_exit(&ds->ds_dir->dd_lock); 2779 } 2780 2781 static void 2782 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 2783 { 2784 dsl_dataset_set_qr_arg_t *ddsqra = arg; 2785 dsl_pool_t *dp = dmu_tx_pool(tx); 2786 dsl_dataset_t *ds; 2787 2788 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 2789 dsl_dataset_set_refreservation_sync_impl(ds, 2790 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 2791 dsl_dataset_rele(ds, FTAG); 2792 } 2793 2794 int 2795 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 2796 uint64_t refreservation) 2797 { 2798 dsl_dataset_set_qr_arg_t ddsqra; 2799 2800 ddsqra.ddsqra_name = dsname; 2801 ddsqra.ddsqra_source = source; 2802 ddsqra.ddsqra_value = refreservation; 2803 2804 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 2805 dsl_dataset_set_refreservation_sync, &ddsqra, 0)); 2806 } 2807 2808 /* 2809 * Return (in *usedp) the amount of space written in new that is not 2810 * present in oldsnap. New may be a snapshot or the head. Old must be 2811 * a snapshot before new, in new's filesystem (or its origin). If not then 2812 * fail and return EINVAL. 2813 * 2814 * The written space is calculated by considering two components: First, we 2815 * ignore any freed space, and calculate the written as new's used space 2816 * minus old's used space. Next, we add in the amount of space that was freed 2817 * between the two snapshots, thus reducing new's used space relative to old's. 2818 * Specifically, this is the space that was born before old->ds_creation_txg, 2819 * and freed before new (ie. on new's deadlist or a previous deadlist). 2820 * 2821 * space freed [---------------------] 2822 * snapshots ---O-------O--------O-------O------ 2823 * oldsnap new 2824 */ 2825 int 2826 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 2827 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2828 { 2829 int err = 0; 2830 uint64_t snapobj; 2831 dsl_pool_t *dp = new->ds_dir->dd_pool; 2832 2833 ASSERT(dsl_pool_config_held(dp)); 2834 2835 *usedp = 0; 2836 *usedp += new->ds_phys->ds_referenced_bytes; 2837 *usedp -= oldsnap->ds_phys->ds_referenced_bytes; 2838 2839 *compp = 0; 2840 *compp += new->ds_phys->ds_compressed_bytes; 2841 *compp -= oldsnap->ds_phys->ds_compressed_bytes; 2842 2843 *uncompp = 0; 2844 *uncompp += new->ds_phys->ds_uncompressed_bytes; 2845 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes; 2846 2847 snapobj = new->ds_object; 2848 while (snapobj != oldsnap->ds_object) { 2849 dsl_dataset_t *snap; 2850 uint64_t used, comp, uncomp; 2851 2852 if (snapobj == new->ds_object) { 2853 snap = new; 2854 } else { 2855 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 2856 if (err != 0) 2857 break; 2858 } 2859 2860 if (snap->ds_phys->ds_prev_snap_txg == 2861 oldsnap->ds_phys->ds_creation_txg) { 2862 /* 2863 * The blocks in the deadlist can not be born after 2864 * ds_prev_snap_txg, so get the whole deadlist space, 2865 * which is more efficient (especially for old-format 2866 * deadlists). Unfortunately the deadlist code 2867 * doesn't have enough information to make this 2868 * optimization itself. 2869 */ 2870 dsl_deadlist_space(&snap->ds_deadlist, 2871 &used, &comp, &uncomp); 2872 } else { 2873 dsl_deadlist_space_range(&snap->ds_deadlist, 2874 0, oldsnap->ds_phys->ds_creation_txg, 2875 &used, &comp, &uncomp); 2876 } 2877 *usedp += used; 2878 *compp += comp; 2879 *uncompp += uncomp; 2880 2881 /* 2882 * If we get to the beginning of the chain of snapshots 2883 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 2884 * was not a snapshot of/before new. 2885 */ 2886 snapobj = snap->ds_phys->ds_prev_snap_obj; 2887 if (snap != new) 2888 dsl_dataset_rele(snap, FTAG); 2889 if (snapobj == 0) { 2890 err = SET_ERROR(EINVAL); 2891 break; 2892 } 2893 2894 } 2895 return (err); 2896 } 2897 2898 /* 2899 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 2900 * lastsnap, and all snapshots in between are deleted. 2901 * 2902 * blocks that would be freed [---------------------------] 2903 * snapshots ---O-------O--------O-------O--------O 2904 * firstsnap lastsnap 2905 * 2906 * This is the set of blocks that were born after the snap before firstsnap, 2907 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 2908 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 2909 * We calculate this by iterating over the relevant deadlists (from the snap 2910 * after lastsnap, backward to the snap after firstsnap), summing up the 2911 * space on the deadlist that was born after the snap before firstsnap. 2912 */ 2913 int 2914 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 2915 dsl_dataset_t *lastsnap, 2916 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 2917 { 2918 int err = 0; 2919 uint64_t snapobj; 2920 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 2921 2922 ASSERT(dsl_dataset_is_snapshot(firstsnap)); 2923 ASSERT(dsl_dataset_is_snapshot(lastsnap)); 2924 2925 /* 2926 * Check that the snapshots are in the same dsl_dir, and firstsnap 2927 * is before lastsnap. 2928 */ 2929 if (firstsnap->ds_dir != lastsnap->ds_dir || 2930 firstsnap->ds_phys->ds_creation_txg > 2931 lastsnap->ds_phys->ds_creation_txg) 2932 return (SET_ERROR(EINVAL)); 2933 2934 *usedp = *compp = *uncompp = 0; 2935 2936 snapobj = lastsnap->ds_phys->ds_next_snap_obj; 2937 while (snapobj != firstsnap->ds_object) { 2938 dsl_dataset_t *ds; 2939 uint64_t used, comp, uncomp; 2940 2941 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 2942 if (err != 0) 2943 break; 2944 2945 dsl_deadlist_space_range(&ds->ds_deadlist, 2946 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2947 &used, &comp, &uncomp); 2948 *usedp += used; 2949 *compp += comp; 2950 *uncompp += uncomp; 2951 2952 snapobj = ds->ds_phys->ds_prev_snap_obj; 2953 ASSERT3U(snapobj, !=, 0); 2954 dsl_dataset_rele(ds, FTAG); 2955 } 2956 return (err); 2957 } 2958 2959 /* 2960 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 2961 * For example, they could both be snapshots of the same filesystem, and 2962 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 2963 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 2964 * filesystem. Or 'earlier' could be the origin's origin. 2965 */ 2966 boolean_t 2967 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier) 2968 { 2969 dsl_pool_t *dp = later->ds_dir->dd_pool; 2970 int error; 2971 boolean_t ret; 2972 2973 ASSERT(dsl_pool_config_held(dp)); 2974 2975 if (earlier->ds_phys->ds_creation_txg >= 2976 later->ds_phys->ds_creation_txg) 2977 return (B_FALSE); 2978 2979 if (later->ds_dir == earlier->ds_dir) 2980 return (B_TRUE); 2981 if (!dsl_dir_is_clone(later->ds_dir)) 2982 return (B_FALSE); 2983 2984 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object) 2985 return (B_TRUE); 2986 dsl_dataset_t *origin; 2987 error = dsl_dataset_hold_obj(dp, 2988 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin); 2989 if (error != 0) 2990 return (B_FALSE); 2991 ret = dsl_dataset_is_before(origin, earlier); 2992 dsl_dataset_rele(origin, FTAG); 2993 return (ret); 2994 } 2995