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) 2011, 2016 by Delphix. All rights reserved. 24 * Copyright (c) 2014, Joyent, Inc. All rights reserved. 25 * Copyright (c) 2014 RackTop Systems. 26 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 27 * Copyright (c) 2014 Integros [integros.com] 28 * Copyright 2016, OmniTI Computer Consulting, Inc. All rights reserved. 29 */ 30 31 #include <sys/dmu_objset.h> 32 #include <sys/dsl_dataset.h> 33 #include <sys/dsl_dir.h> 34 #include <sys/dsl_prop.h> 35 #include <sys/dsl_synctask.h> 36 #include <sys/dmu_traverse.h> 37 #include <sys/dmu_impl.h> 38 #include <sys/dmu_tx.h> 39 #include <sys/arc.h> 40 #include <sys/zio.h> 41 #include <sys/zap.h> 42 #include <sys/zfeature.h> 43 #include <sys/unique.h> 44 #include <sys/zfs_context.h> 45 #include <sys/zfs_ioctl.h> 46 #include <sys/spa.h> 47 #include <sys/zfs_znode.h> 48 #include <sys/zfs_onexit.h> 49 #include <sys/zvol.h> 50 #include <sys/dsl_scan.h> 51 #include <sys/dsl_deadlist.h> 52 #include <sys/dsl_destroy.h> 53 #include <sys/dsl_userhold.h> 54 #include <sys/dsl_bookmark.h> 55 #include <sys/dmu_send.h> 56 #include <sys/zio_checksum.h> 57 #include <sys/zio_compress.h> 58 #include <zfs_fletcher.h> 59 60 /* 61 * The SPA supports block sizes up to 16MB. However, very large blocks 62 * can have an impact on i/o latency (e.g. tying up a spinning disk for 63 * ~300ms), and also potentially on the memory allocator. Therefore, 64 * we do not allow the recordsize to be set larger than zfs_max_recordsize 65 * (default 1MB). Larger blocks can be created by changing this tunable, 66 * and pools with larger blocks can always be imported and used, regardless 67 * of this setting. 68 */ 69 int zfs_max_recordsize = 1 * 1024 * 1024; 70 71 #define SWITCH64(x, y) \ 72 { \ 73 uint64_t __tmp = (x); \ 74 (x) = (y); \ 75 (y) = __tmp; \ 76 } 77 78 #define DS_REF_MAX (1ULL << 62) 79 80 extern inline dsl_dataset_phys_t *dsl_dataset_phys(dsl_dataset_t *ds); 81 82 extern int spa_asize_inflation; 83 84 /* 85 * Figure out how much of this delta should be propogated to the dsl_dir 86 * layer. If there's a refreservation, that space has already been 87 * partially accounted for in our ancestors. 88 */ 89 static int64_t 90 parent_delta(dsl_dataset_t *ds, int64_t delta) 91 { 92 dsl_dataset_phys_t *ds_phys; 93 uint64_t old_bytes, new_bytes; 94 95 if (ds->ds_reserved == 0) 96 return (delta); 97 98 ds_phys = dsl_dataset_phys(ds); 99 old_bytes = MAX(ds_phys->ds_unique_bytes, ds->ds_reserved); 100 new_bytes = MAX(ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 101 102 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 103 return (new_bytes - old_bytes); 104 } 105 106 void 107 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 108 { 109 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 110 int compressed = BP_GET_PSIZE(bp); 111 int uncompressed = BP_GET_UCSIZE(bp); 112 int64_t delta; 113 114 dprintf_bp(bp, "ds=%p", ds); 115 116 ASSERT(dmu_tx_is_syncing(tx)); 117 /* It could have been compressed away to nothing */ 118 if (BP_IS_HOLE(bp)) 119 return; 120 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 121 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 122 if (ds == NULL) { 123 dsl_pool_mos_diduse_space(tx->tx_pool, 124 used, compressed, uncompressed); 125 return; 126 } 127 128 dmu_buf_will_dirty(ds->ds_dbuf, tx); 129 mutex_enter(&ds->ds_lock); 130 delta = parent_delta(ds, used); 131 dsl_dataset_phys(ds)->ds_referenced_bytes += used; 132 dsl_dataset_phys(ds)->ds_compressed_bytes += compressed; 133 dsl_dataset_phys(ds)->ds_uncompressed_bytes += uncompressed; 134 dsl_dataset_phys(ds)->ds_unique_bytes += used; 135 136 if (BP_GET_LSIZE(bp) > SPA_OLD_MAXBLOCKSIZE) { 137 ds->ds_feature_activation_needed[SPA_FEATURE_LARGE_BLOCKS] = 138 B_TRUE; 139 } 140 141 spa_feature_t f = zio_checksum_to_feature(BP_GET_CHECKSUM(bp)); 142 if (f != SPA_FEATURE_NONE) 143 ds->ds_feature_activation_needed[f] = B_TRUE; 144 145 mutex_exit(&ds->ds_lock); 146 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 147 compressed, uncompressed, tx); 148 dsl_dir_transfer_space(ds->ds_dir, used - delta, 149 DD_USED_REFRSRV, DD_USED_HEAD, tx); 150 } 151 152 int 153 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 154 boolean_t async) 155 { 156 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 157 int compressed = BP_GET_PSIZE(bp); 158 int uncompressed = BP_GET_UCSIZE(bp); 159 160 if (BP_IS_HOLE(bp)) 161 return (0); 162 163 ASSERT(dmu_tx_is_syncing(tx)); 164 ASSERT(bp->blk_birth <= tx->tx_txg); 165 166 if (ds == NULL) { 167 dsl_free(tx->tx_pool, tx->tx_txg, bp); 168 dsl_pool_mos_diduse_space(tx->tx_pool, 169 -used, -compressed, -uncompressed); 170 return (used); 171 } 172 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 173 174 ASSERT(!ds->ds_is_snapshot); 175 dmu_buf_will_dirty(ds->ds_dbuf, tx); 176 177 if (bp->blk_birth > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 178 int64_t delta; 179 180 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 181 dsl_free(tx->tx_pool, tx->tx_txg, bp); 182 183 mutex_enter(&ds->ds_lock); 184 ASSERT(dsl_dataset_phys(ds)->ds_unique_bytes >= used || 185 !DS_UNIQUE_IS_ACCURATE(ds)); 186 delta = parent_delta(ds, -used); 187 dsl_dataset_phys(ds)->ds_unique_bytes -= used; 188 mutex_exit(&ds->ds_lock); 189 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 190 delta, -compressed, -uncompressed, tx); 191 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 192 DD_USED_REFRSRV, DD_USED_HEAD, tx); 193 } else { 194 dprintf_bp(bp, "putting on dead list: %s", ""); 195 if (async) { 196 /* 197 * We are here as part of zio's write done callback, 198 * which means we're a zio interrupt thread. We can't 199 * call dsl_deadlist_insert() now because it may block 200 * waiting for I/O. Instead, put bp on the deferred 201 * queue and let dsl_pool_sync() finish the job. 202 */ 203 bplist_append(&ds->ds_pending_deadlist, bp); 204 } else { 205 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 206 } 207 ASSERT3U(ds->ds_prev->ds_object, ==, 208 dsl_dataset_phys(ds)->ds_prev_snap_obj); 209 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_num_children > 0); 210 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 211 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 212 ds->ds_object && bp->blk_birth > 213 dsl_dataset_phys(ds->ds_prev)->ds_prev_snap_txg) { 214 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 215 mutex_enter(&ds->ds_prev->ds_lock); 216 dsl_dataset_phys(ds->ds_prev)->ds_unique_bytes += used; 217 mutex_exit(&ds->ds_prev->ds_lock); 218 } 219 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 220 dsl_dir_transfer_space(ds->ds_dir, used, 221 DD_USED_HEAD, DD_USED_SNAP, tx); 222 } 223 } 224 mutex_enter(&ds->ds_lock); 225 ASSERT3U(dsl_dataset_phys(ds)->ds_referenced_bytes, >=, used); 226 dsl_dataset_phys(ds)->ds_referenced_bytes -= used; 227 ASSERT3U(dsl_dataset_phys(ds)->ds_compressed_bytes, >=, compressed); 228 dsl_dataset_phys(ds)->ds_compressed_bytes -= compressed; 229 ASSERT3U(dsl_dataset_phys(ds)->ds_uncompressed_bytes, >=, uncompressed); 230 dsl_dataset_phys(ds)->ds_uncompressed_bytes -= uncompressed; 231 mutex_exit(&ds->ds_lock); 232 233 return (used); 234 } 235 236 uint64_t 237 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 238 { 239 uint64_t trysnap = 0; 240 241 if (ds == NULL) 242 return (0); 243 /* 244 * The snapshot creation could fail, but that would cause an 245 * incorrect FALSE return, which would only result in an 246 * overestimation of the amount of space that an operation would 247 * consume, which is OK. 248 * 249 * There's also a small window where we could miss a pending 250 * snapshot, because we could set the sync task in the quiescing 251 * phase. So this should only be used as a guess. 252 */ 253 if (ds->ds_trysnap_txg > 254 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 255 trysnap = ds->ds_trysnap_txg; 256 return (MAX(dsl_dataset_phys(ds)->ds_prev_snap_txg, trysnap)); 257 } 258 259 boolean_t 260 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp, 261 uint64_t blk_birth) 262 { 263 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) || 264 (bp != NULL && BP_IS_HOLE(bp))) 265 return (B_FALSE); 266 267 ddt_prefetch(dsl_dataset_get_spa(ds), bp); 268 269 return (B_TRUE); 270 } 271 272 /* 273 * We have to release the fsid syncronously or we risk that a subsequent 274 * mount of the same dataset will fail to unique_insert the fsid. This 275 * failure would manifest itself as the fsid of this dataset changing 276 * between mounts which makes NFS clients quite unhappy. 277 */ 278 static void 279 dsl_dataset_evict_sync(void *dbu) 280 { 281 dsl_dataset_t *ds = dbu; 282 283 ASSERT(ds->ds_owner == NULL); 284 285 unique_remove(ds->ds_fsid_guid); 286 } 287 288 static void 289 dsl_dataset_evict_async(void *dbu) 290 { 291 dsl_dataset_t *ds = dbu; 292 293 ASSERT(ds->ds_owner == NULL); 294 295 ds->ds_dbuf = NULL; 296 297 if (ds->ds_objset != NULL) 298 dmu_objset_evict(ds->ds_objset); 299 300 if (ds->ds_prev) { 301 dsl_dataset_rele(ds->ds_prev, ds); 302 ds->ds_prev = NULL; 303 } 304 305 bplist_destroy(&ds->ds_pending_deadlist); 306 if (ds->ds_deadlist.dl_os != NULL) 307 dsl_deadlist_close(&ds->ds_deadlist); 308 if (ds->ds_dir) 309 dsl_dir_async_rele(ds->ds_dir, ds); 310 311 ASSERT(!list_link_active(&ds->ds_synced_link)); 312 313 list_destroy(&ds->ds_prop_cbs); 314 mutex_destroy(&ds->ds_lock); 315 mutex_destroy(&ds->ds_opening_lock); 316 mutex_destroy(&ds->ds_sendstream_lock); 317 refcount_destroy(&ds->ds_longholds); 318 319 kmem_free(ds, sizeof (dsl_dataset_t)); 320 } 321 322 int 323 dsl_dataset_get_snapname(dsl_dataset_t *ds) 324 { 325 dsl_dataset_phys_t *headphys; 326 int err; 327 dmu_buf_t *headdbuf; 328 dsl_pool_t *dp = ds->ds_dir->dd_pool; 329 objset_t *mos = dp->dp_meta_objset; 330 331 if (ds->ds_snapname[0]) 332 return (0); 333 if (dsl_dataset_phys(ds)->ds_next_snap_obj == 0) 334 return (0); 335 336 err = dmu_bonus_hold(mos, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, 337 FTAG, &headdbuf); 338 if (err != 0) 339 return (err); 340 headphys = headdbuf->db_data; 341 err = zap_value_search(dp->dp_meta_objset, 342 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 343 dmu_buf_rele(headdbuf, FTAG); 344 return (err); 345 } 346 347 int 348 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 349 { 350 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 351 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 352 matchtype_t mt; 353 int err; 354 355 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 356 mt = MT_FIRST; 357 else 358 mt = MT_EXACT; 359 360 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 361 value, mt, NULL, 0, NULL); 362 if (err == ENOTSUP && mt == MT_FIRST) 363 err = zap_lookup(mos, snapobj, name, 8, 1, value); 364 return (err); 365 } 366 367 int 368 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx, 369 boolean_t adj_cnt) 370 { 371 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 372 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 373 matchtype_t mt; 374 int err; 375 376 dsl_dir_snap_cmtime_update(ds->ds_dir); 377 378 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 379 mt = MT_FIRST; 380 else 381 mt = MT_EXACT; 382 383 err = zap_remove_norm(mos, snapobj, name, mt, tx); 384 if (err == ENOTSUP && mt == MT_FIRST) 385 err = zap_remove(mos, snapobj, name, tx); 386 387 if (err == 0 && adj_cnt) 388 dsl_fs_ss_count_adjust(ds->ds_dir, -1, 389 DD_FIELD_SNAPSHOT_COUNT, tx); 390 391 return (err); 392 } 393 394 boolean_t 395 dsl_dataset_try_add_ref(dsl_pool_t *dp, dsl_dataset_t *ds, void *tag) 396 { 397 dmu_buf_t *dbuf = ds->ds_dbuf; 398 boolean_t result = B_FALSE; 399 400 if (dbuf != NULL && dmu_buf_try_add_ref(dbuf, dp->dp_meta_objset, 401 ds->ds_object, DMU_BONUS_BLKID, tag)) { 402 403 if (ds == dmu_buf_get_user(dbuf)) 404 result = B_TRUE; 405 else 406 dmu_buf_rele(dbuf, tag); 407 } 408 409 return (result); 410 } 411 412 int 413 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 414 dsl_dataset_t **dsp) 415 { 416 objset_t *mos = dp->dp_meta_objset; 417 dmu_buf_t *dbuf; 418 dsl_dataset_t *ds; 419 int err; 420 dmu_object_info_t doi; 421 422 ASSERT(dsl_pool_config_held(dp)); 423 424 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 425 if (err != 0) 426 return (err); 427 428 /* Make sure dsobj has the correct object type. */ 429 dmu_object_info_from_db(dbuf, &doi); 430 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) { 431 dmu_buf_rele(dbuf, tag); 432 return (SET_ERROR(EINVAL)); 433 } 434 435 ds = dmu_buf_get_user(dbuf); 436 if (ds == NULL) { 437 dsl_dataset_t *winner = NULL; 438 439 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 440 ds->ds_dbuf = dbuf; 441 ds->ds_object = dsobj; 442 ds->ds_is_snapshot = dsl_dataset_phys(ds)->ds_num_children != 0; 443 444 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 445 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 446 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 447 refcount_create(&ds->ds_longholds); 448 449 bplist_create(&ds->ds_pending_deadlist); 450 dsl_deadlist_open(&ds->ds_deadlist, 451 mos, dsl_dataset_phys(ds)->ds_deadlist_obj); 452 453 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 454 offsetof(dmu_sendarg_t, dsa_link)); 455 456 list_create(&ds->ds_prop_cbs, sizeof (dsl_prop_cb_record_t), 457 offsetof(dsl_prop_cb_record_t, cbr_ds_node)); 458 459 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 460 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 461 if (!(spa_feature_table[f].fi_flags & 462 ZFEATURE_FLAG_PER_DATASET)) 463 continue; 464 err = zap_contains(mos, dsobj, 465 spa_feature_table[f].fi_guid); 466 if (err == 0) { 467 ds->ds_feature_inuse[f] = B_TRUE; 468 } else { 469 ASSERT3U(err, ==, ENOENT); 470 err = 0; 471 } 472 } 473 } 474 475 err = dsl_dir_hold_obj(dp, 476 dsl_dataset_phys(ds)->ds_dir_obj, NULL, ds, &ds->ds_dir); 477 if (err != 0) { 478 mutex_destroy(&ds->ds_lock); 479 mutex_destroy(&ds->ds_opening_lock); 480 mutex_destroy(&ds->ds_sendstream_lock); 481 refcount_destroy(&ds->ds_longholds); 482 bplist_destroy(&ds->ds_pending_deadlist); 483 dsl_deadlist_close(&ds->ds_deadlist); 484 kmem_free(ds, sizeof (dsl_dataset_t)); 485 dmu_buf_rele(dbuf, tag); 486 return (err); 487 } 488 489 if (!ds->ds_is_snapshot) { 490 ds->ds_snapname[0] = '\0'; 491 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 492 err = dsl_dataset_hold_obj(dp, 493 dsl_dataset_phys(ds)->ds_prev_snap_obj, 494 ds, &ds->ds_prev); 495 } 496 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 497 int zaperr = zap_lookup(mos, ds->ds_object, 498 DS_FIELD_BOOKMARK_NAMES, 499 sizeof (ds->ds_bookmarks), 1, 500 &ds->ds_bookmarks); 501 if (zaperr != ENOENT) 502 VERIFY0(zaperr); 503 } 504 } else { 505 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 506 err = dsl_dataset_get_snapname(ds); 507 if (err == 0 && 508 dsl_dataset_phys(ds)->ds_userrefs_obj != 0) { 509 err = zap_count( 510 ds->ds_dir->dd_pool->dp_meta_objset, 511 dsl_dataset_phys(ds)->ds_userrefs_obj, 512 &ds->ds_userrefs); 513 } 514 } 515 516 if (err == 0 && !ds->ds_is_snapshot) { 517 err = dsl_prop_get_int_ds(ds, 518 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 519 &ds->ds_reserved); 520 if (err == 0) { 521 err = dsl_prop_get_int_ds(ds, 522 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 523 &ds->ds_quota); 524 } 525 } else { 526 ds->ds_reserved = ds->ds_quota = 0; 527 } 528 529 dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict_sync, 530 dsl_dataset_evict_async, &ds->ds_dbuf); 531 if (err == 0) 532 winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu); 533 534 if (err != 0 || winner != NULL) { 535 bplist_destroy(&ds->ds_pending_deadlist); 536 dsl_deadlist_close(&ds->ds_deadlist); 537 if (ds->ds_prev) 538 dsl_dataset_rele(ds->ds_prev, ds); 539 dsl_dir_rele(ds->ds_dir, ds); 540 mutex_destroy(&ds->ds_lock); 541 mutex_destroy(&ds->ds_opening_lock); 542 mutex_destroy(&ds->ds_sendstream_lock); 543 refcount_destroy(&ds->ds_longholds); 544 kmem_free(ds, sizeof (dsl_dataset_t)); 545 if (err != 0) { 546 dmu_buf_rele(dbuf, tag); 547 return (err); 548 } 549 ds = winner; 550 } else { 551 ds->ds_fsid_guid = 552 unique_insert(dsl_dataset_phys(ds)->ds_fsid_guid); 553 if (ds->ds_fsid_guid != 554 dsl_dataset_phys(ds)->ds_fsid_guid) { 555 zfs_dbgmsg("ds_fsid_guid changed from " 556 "%llx to %llx for pool %s dataset id %llu", 557 (long long) 558 dsl_dataset_phys(ds)->ds_fsid_guid, 559 (long long)ds->ds_fsid_guid, 560 spa_name(dp->dp_spa), 561 dsobj); 562 } 563 } 564 } 565 ASSERT3P(ds->ds_dbuf, ==, dbuf); 566 ASSERT3P(dsl_dataset_phys(ds), ==, dbuf->db_data); 567 ASSERT(dsl_dataset_phys(ds)->ds_prev_snap_obj != 0 || 568 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 569 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 570 *dsp = ds; 571 return (0); 572 } 573 574 int 575 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 576 void *tag, dsl_dataset_t **dsp) 577 { 578 dsl_dir_t *dd; 579 const char *snapname; 580 uint64_t obj; 581 int err = 0; 582 dsl_dataset_t *ds; 583 584 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 585 if (err != 0) 586 return (err); 587 588 ASSERT(dsl_pool_config_held(dp)); 589 obj = dsl_dir_phys(dd)->dd_head_dataset_obj; 590 if (obj != 0) 591 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 592 else 593 err = SET_ERROR(ENOENT); 594 595 /* we may be looking for a snapshot */ 596 if (err == 0 && snapname != NULL) { 597 dsl_dataset_t *snap_ds; 598 599 if (*snapname++ != '@') { 600 dsl_dataset_rele(ds, tag); 601 dsl_dir_rele(dd, FTAG); 602 return (SET_ERROR(ENOENT)); 603 } 604 605 dprintf("looking for snapshot '%s'\n", snapname); 606 err = dsl_dataset_snap_lookup(ds, snapname, &obj); 607 if (err == 0) 608 err = dsl_dataset_hold_obj(dp, obj, tag, &snap_ds); 609 dsl_dataset_rele(ds, tag); 610 611 if (err == 0) { 612 mutex_enter(&snap_ds->ds_lock); 613 if (snap_ds->ds_snapname[0] == 0) 614 (void) strlcpy(snap_ds->ds_snapname, snapname, 615 sizeof (snap_ds->ds_snapname)); 616 mutex_exit(&snap_ds->ds_lock); 617 ds = snap_ds; 618 } 619 } 620 if (err == 0) 621 *dsp = ds; 622 dsl_dir_rele(dd, FTAG); 623 return (err); 624 } 625 626 int 627 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 628 void *tag, dsl_dataset_t **dsp) 629 { 630 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 631 if (err != 0) 632 return (err); 633 if (!dsl_dataset_tryown(*dsp, tag)) { 634 dsl_dataset_rele(*dsp, tag); 635 *dsp = NULL; 636 return (SET_ERROR(EBUSY)); 637 } 638 return (0); 639 } 640 641 int 642 dsl_dataset_own(dsl_pool_t *dp, const char *name, 643 void *tag, dsl_dataset_t **dsp) 644 { 645 int err = dsl_dataset_hold(dp, name, tag, dsp); 646 if (err != 0) 647 return (err); 648 if (!dsl_dataset_tryown(*dsp, tag)) { 649 dsl_dataset_rele(*dsp, tag); 650 return (SET_ERROR(EBUSY)); 651 } 652 return (0); 653 } 654 655 /* 656 * See the comment above dsl_pool_hold() for details. In summary, a long 657 * hold is used to prevent destruction of a dataset while the pool hold 658 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 659 * 660 * The dataset and pool must be held when this function is called. After it 661 * is called, the pool hold may be released while the dataset is still held 662 * and accessed. 663 */ 664 void 665 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 666 { 667 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 668 (void) refcount_add(&ds->ds_longholds, tag); 669 } 670 671 void 672 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 673 { 674 (void) refcount_remove(&ds->ds_longholds, tag); 675 } 676 677 /* Return B_TRUE if there are any long holds on this dataset. */ 678 boolean_t 679 dsl_dataset_long_held(dsl_dataset_t *ds) 680 { 681 return (!refcount_is_zero(&ds->ds_longholds)); 682 } 683 684 void 685 dsl_dataset_name(dsl_dataset_t *ds, char *name) 686 { 687 if (ds == NULL) { 688 (void) strcpy(name, "mos"); 689 } else { 690 dsl_dir_name(ds->ds_dir, name); 691 VERIFY0(dsl_dataset_get_snapname(ds)); 692 if (ds->ds_snapname[0]) { 693 VERIFY3U(strlcat(name, "@", ZFS_MAX_DATASET_NAME_LEN), 694 <, ZFS_MAX_DATASET_NAME_LEN); 695 /* 696 * We use a "recursive" mutex so that we 697 * can call dprintf_ds() with ds_lock held. 698 */ 699 if (!MUTEX_HELD(&ds->ds_lock)) { 700 mutex_enter(&ds->ds_lock); 701 VERIFY3U(strlcat(name, ds->ds_snapname, 702 ZFS_MAX_DATASET_NAME_LEN), <, 703 ZFS_MAX_DATASET_NAME_LEN); 704 mutex_exit(&ds->ds_lock); 705 } else { 706 VERIFY3U(strlcat(name, ds->ds_snapname, 707 ZFS_MAX_DATASET_NAME_LEN), <, 708 ZFS_MAX_DATASET_NAME_LEN); 709 } 710 } 711 } 712 } 713 714 int 715 dsl_dataset_namelen(dsl_dataset_t *ds) 716 { 717 VERIFY0(dsl_dataset_get_snapname(ds)); 718 mutex_enter(&ds->ds_lock); 719 int len = dsl_dir_namelen(ds->ds_dir) + 1 + strlen(ds->ds_snapname); 720 mutex_exit(&ds->ds_lock); 721 return (len); 722 } 723 724 void 725 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 726 { 727 dmu_buf_rele(ds->ds_dbuf, tag); 728 } 729 730 void 731 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 732 { 733 ASSERT3P(ds->ds_owner, ==, tag); 734 ASSERT(ds->ds_dbuf != NULL); 735 736 mutex_enter(&ds->ds_lock); 737 ds->ds_owner = NULL; 738 mutex_exit(&ds->ds_lock); 739 dsl_dataset_long_rele(ds, tag); 740 dsl_dataset_rele(ds, tag); 741 } 742 743 boolean_t 744 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 745 { 746 boolean_t gotit = FALSE; 747 748 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 749 mutex_enter(&ds->ds_lock); 750 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 751 ds->ds_owner = tag; 752 dsl_dataset_long_hold(ds, tag); 753 gotit = TRUE; 754 } 755 mutex_exit(&ds->ds_lock); 756 return (gotit); 757 } 758 759 boolean_t 760 dsl_dataset_has_owner(dsl_dataset_t *ds) 761 { 762 boolean_t rv; 763 mutex_enter(&ds->ds_lock); 764 rv = (ds->ds_owner != NULL); 765 mutex_exit(&ds->ds_lock); 766 return (rv); 767 } 768 769 static void 770 dsl_dataset_activate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 771 { 772 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 773 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 774 uint64_t zero = 0; 775 776 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 777 778 spa_feature_incr(spa, f, tx); 779 dmu_object_zapify(mos, dsobj, DMU_OT_DSL_DATASET, tx); 780 781 VERIFY0(zap_add(mos, dsobj, spa_feature_table[f].fi_guid, 782 sizeof (zero), 1, &zero, tx)); 783 } 784 785 void 786 dsl_dataset_deactivate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 787 { 788 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 789 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 790 791 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 792 793 VERIFY0(zap_remove(mos, dsobj, spa_feature_table[f].fi_guid, tx)); 794 spa_feature_decr(spa, f, tx); 795 } 796 797 uint64_t 798 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 799 uint64_t flags, dmu_tx_t *tx) 800 { 801 dsl_pool_t *dp = dd->dd_pool; 802 dmu_buf_t *dbuf; 803 dsl_dataset_phys_t *dsphys; 804 uint64_t dsobj; 805 objset_t *mos = dp->dp_meta_objset; 806 807 if (origin == NULL) 808 origin = dp->dp_origin_snap; 809 810 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 811 ASSERT(origin == NULL || dsl_dataset_phys(origin)->ds_num_children > 0); 812 ASSERT(dmu_tx_is_syncing(tx)); 813 ASSERT(dsl_dir_phys(dd)->dd_head_dataset_obj == 0); 814 815 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 816 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 817 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 818 dmu_buf_will_dirty(dbuf, tx); 819 dsphys = dbuf->db_data; 820 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 821 dsphys->ds_dir_obj = dd->dd_object; 822 dsphys->ds_flags = flags; 823 dsphys->ds_fsid_guid = unique_create(); 824 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 825 sizeof (dsphys->ds_guid)); 826 dsphys->ds_snapnames_zapobj = 827 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 828 DMU_OT_NONE, 0, tx); 829 dsphys->ds_creation_time = gethrestime_sec(); 830 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 831 832 if (origin == NULL) { 833 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 834 } else { 835 dsl_dataset_t *ohds; /* head of the origin snapshot */ 836 837 dsphys->ds_prev_snap_obj = origin->ds_object; 838 dsphys->ds_prev_snap_txg = 839 dsl_dataset_phys(origin)->ds_creation_txg; 840 dsphys->ds_referenced_bytes = 841 dsl_dataset_phys(origin)->ds_referenced_bytes; 842 dsphys->ds_compressed_bytes = 843 dsl_dataset_phys(origin)->ds_compressed_bytes; 844 dsphys->ds_uncompressed_bytes = 845 dsl_dataset_phys(origin)->ds_uncompressed_bytes; 846 dsphys->ds_bp = dsl_dataset_phys(origin)->ds_bp; 847 848 /* 849 * Inherit flags that describe the dataset's contents 850 * (INCONSISTENT) or properties (Case Insensitive). 851 */ 852 dsphys->ds_flags |= dsl_dataset_phys(origin)->ds_flags & 853 (DS_FLAG_INCONSISTENT | DS_FLAG_CI_DATASET); 854 855 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 856 if (origin->ds_feature_inuse[f]) 857 dsl_dataset_activate_feature(dsobj, f, tx); 858 } 859 860 dmu_buf_will_dirty(origin->ds_dbuf, tx); 861 dsl_dataset_phys(origin)->ds_num_children++; 862 863 VERIFY0(dsl_dataset_hold_obj(dp, 864 dsl_dir_phys(origin->ds_dir)->dd_head_dataset_obj, 865 FTAG, &ohds)); 866 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 867 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 868 dsl_dataset_rele(ohds, FTAG); 869 870 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 871 if (dsl_dataset_phys(origin)->ds_next_clones_obj == 0) { 872 dsl_dataset_phys(origin)->ds_next_clones_obj = 873 zap_create(mos, 874 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 875 } 876 VERIFY0(zap_add_int(mos, 877 dsl_dataset_phys(origin)->ds_next_clones_obj, 878 dsobj, tx)); 879 } 880 881 dmu_buf_will_dirty(dd->dd_dbuf, tx); 882 dsl_dir_phys(dd)->dd_origin_obj = origin->ds_object; 883 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 884 if (dsl_dir_phys(origin->ds_dir)->dd_clones == 0) { 885 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 886 dsl_dir_phys(origin->ds_dir)->dd_clones = 887 zap_create(mos, 888 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 889 } 890 VERIFY0(zap_add_int(mos, 891 dsl_dir_phys(origin->ds_dir)->dd_clones, 892 dsobj, tx)); 893 } 894 } 895 896 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 897 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 898 899 dmu_buf_rele(dbuf, FTAG); 900 901 dmu_buf_will_dirty(dd->dd_dbuf, tx); 902 dsl_dir_phys(dd)->dd_head_dataset_obj = dsobj; 903 904 return (dsobj); 905 } 906 907 static void 908 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 909 { 910 objset_t *os; 911 912 VERIFY0(dmu_objset_from_ds(ds, &os)); 913 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 914 dsl_dataset_dirty(ds, tx); 915 } 916 917 uint64_t 918 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 919 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 920 { 921 dsl_pool_t *dp = pdd->dd_pool; 922 uint64_t dsobj, ddobj; 923 dsl_dir_t *dd; 924 925 ASSERT(dmu_tx_is_syncing(tx)); 926 ASSERT(lastname[0] != '@'); 927 928 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 929 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 930 931 dsobj = dsl_dataset_create_sync_dd(dd, origin, 932 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 933 934 dsl_deleg_set_create_perms(dd, tx, cr); 935 936 /* 937 * Since we're creating a new node we know it's a leaf, so we can 938 * initialize the counts if the limit feature is active. 939 */ 940 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) { 941 uint64_t cnt = 0; 942 objset_t *os = dd->dd_pool->dp_meta_objset; 943 944 dsl_dir_zapify(dd, tx); 945 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT, 946 sizeof (cnt), 1, &cnt, tx)); 947 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT, 948 sizeof (cnt), 1, &cnt, tx)); 949 } 950 951 dsl_dir_rele(dd, FTAG); 952 953 /* 954 * If we are creating a clone, make sure we zero out any stale 955 * data from the origin snapshots zil header. 956 */ 957 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 958 dsl_dataset_t *ds; 959 960 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 961 dsl_dataset_zero_zil(ds, tx); 962 dsl_dataset_rele(ds, FTAG); 963 } 964 965 return (dsobj); 966 } 967 968 /* 969 * The unique space in the head dataset can be calculated by subtracting 970 * the space used in the most recent snapshot, that is still being used 971 * in this file system, from the space currently in use. To figure out 972 * the space in the most recent snapshot still in use, we need to take 973 * the total space used in the snapshot and subtract out the space that 974 * has been freed up since the snapshot was taken. 975 */ 976 void 977 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 978 { 979 uint64_t mrs_used; 980 uint64_t dlused, dlcomp, dluncomp; 981 982 ASSERT(!ds->ds_is_snapshot); 983 984 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) 985 mrs_used = dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes; 986 else 987 mrs_used = 0; 988 989 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 990 991 ASSERT3U(dlused, <=, mrs_used); 992 dsl_dataset_phys(ds)->ds_unique_bytes = 993 dsl_dataset_phys(ds)->ds_referenced_bytes - (mrs_used - dlused); 994 995 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 996 SPA_VERSION_UNIQUE_ACCURATE) 997 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 998 } 999 1000 void 1001 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 1002 dmu_tx_t *tx) 1003 { 1004 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1005 uint64_t count; 1006 int err; 1007 1008 ASSERT(dsl_dataset_phys(ds)->ds_num_children >= 2); 1009 err = zap_remove_int(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1010 obj, tx); 1011 /* 1012 * The err should not be ENOENT, but a bug in a previous version 1013 * of the code could cause upgrade_clones_cb() to not set 1014 * ds_next_snap_obj when it should, leading to a missing entry. 1015 * If we knew that the pool was created after 1016 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 1017 * ENOENT. However, at least we can check that we don't have 1018 * too many entries in the next_clones_obj even after failing to 1019 * remove this one. 1020 */ 1021 if (err != ENOENT) 1022 VERIFY0(err); 1023 ASSERT0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1024 &count)); 1025 ASSERT3U(count, <=, dsl_dataset_phys(ds)->ds_num_children - 2); 1026 } 1027 1028 1029 blkptr_t * 1030 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1031 { 1032 return (&dsl_dataset_phys(ds)->ds_bp); 1033 } 1034 1035 void 1036 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1037 { 1038 ASSERT(dmu_tx_is_syncing(tx)); 1039 /* If it's the meta-objset, set dp_meta_rootbp */ 1040 if (ds == NULL) { 1041 tx->tx_pool->dp_meta_rootbp = *bp; 1042 } else { 1043 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1044 dsl_dataset_phys(ds)->ds_bp = *bp; 1045 } 1046 } 1047 1048 spa_t * 1049 dsl_dataset_get_spa(dsl_dataset_t *ds) 1050 { 1051 return (ds->ds_dir->dd_pool->dp_spa); 1052 } 1053 1054 void 1055 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1056 { 1057 dsl_pool_t *dp; 1058 1059 if (ds == NULL) /* this is the meta-objset */ 1060 return; 1061 1062 ASSERT(ds->ds_objset != NULL); 1063 1064 if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) 1065 panic("dirtying snapshot!"); 1066 1067 dp = ds->ds_dir->dd_pool; 1068 1069 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 1070 /* up the hold count until we can be written out */ 1071 dmu_buf_add_ref(ds->ds_dbuf, ds); 1072 } 1073 } 1074 1075 boolean_t 1076 dsl_dataset_is_dirty(dsl_dataset_t *ds) 1077 { 1078 for (int t = 0; t < TXG_SIZE; t++) { 1079 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 1080 ds, t)) 1081 return (B_TRUE); 1082 } 1083 return (B_FALSE); 1084 } 1085 1086 static int 1087 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1088 { 1089 uint64_t asize; 1090 1091 if (!dmu_tx_is_syncing(tx)) 1092 return (0); 1093 1094 /* 1095 * If there's an fs-only reservation, any blocks that might become 1096 * owned by the snapshot dataset must be accommodated by space 1097 * outside of the reservation. 1098 */ 1099 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 1100 asize = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, ds->ds_reserved); 1101 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 1102 return (SET_ERROR(ENOSPC)); 1103 1104 /* 1105 * Propagate any reserved space for this snapshot to other 1106 * snapshot checks in this sync group. 1107 */ 1108 if (asize > 0) 1109 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1110 1111 return (0); 1112 } 1113 1114 typedef struct dsl_dataset_snapshot_arg { 1115 nvlist_t *ddsa_snaps; 1116 nvlist_t *ddsa_props; 1117 nvlist_t *ddsa_errors; 1118 cred_t *ddsa_cr; 1119 } dsl_dataset_snapshot_arg_t; 1120 1121 int 1122 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 1123 dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr) 1124 { 1125 int error; 1126 uint64_t value; 1127 1128 ds->ds_trysnap_txg = tx->tx_txg; 1129 1130 if (!dmu_tx_is_syncing(tx)) 1131 return (0); 1132 1133 /* 1134 * We don't allow multiple snapshots of the same txg. If there 1135 * is already one, try again. 1136 */ 1137 if (dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg) 1138 return (SET_ERROR(EAGAIN)); 1139 1140 /* 1141 * Check for conflicting snapshot name. 1142 */ 1143 error = dsl_dataset_snap_lookup(ds, snapname, &value); 1144 if (error == 0) 1145 return (SET_ERROR(EEXIST)); 1146 if (error != ENOENT) 1147 return (error); 1148 1149 /* 1150 * We don't allow taking snapshots of inconsistent datasets, such as 1151 * those into which we are currently receiving. However, if we are 1152 * creating this snapshot as part of a receive, this check will be 1153 * executed atomically with respect to the completion of the receive 1154 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 1155 * case we ignore this, knowing it will be fixed up for us shortly in 1156 * dmu_recv_end_sync(). 1157 */ 1158 if (!recv && DS_IS_INCONSISTENT(ds)) 1159 return (SET_ERROR(EBUSY)); 1160 1161 /* 1162 * Skip the check for temporary snapshots or if we have already checked 1163 * the counts in dsl_dataset_snapshot_check. This means we really only 1164 * check the count here when we're receiving a stream. 1165 */ 1166 if (cnt != 0 && cr != NULL) { 1167 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1168 ZFS_PROP_SNAPSHOT_LIMIT, NULL, cr); 1169 if (error != 0) 1170 return (error); 1171 } 1172 1173 error = dsl_dataset_snapshot_reserve_space(ds, tx); 1174 if (error != 0) 1175 return (error); 1176 1177 return (0); 1178 } 1179 1180 static int 1181 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 1182 { 1183 dsl_dataset_snapshot_arg_t *ddsa = arg; 1184 dsl_pool_t *dp = dmu_tx_pool(tx); 1185 nvpair_t *pair; 1186 int rv = 0; 1187 1188 /* 1189 * Pre-compute how many total new snapshots will be created for each 1190 * level in the tree and below. This is needed for validating the 1191 * snapshot limit when either taking a recursive snapshot or when 1192 * taking multiple snapshots. 1193 * 1194 * The problem is that the counts are not actually adjusted when 1195 * we are checking, only when we finally sync. For a single snapshot, 1196 * this is easy, the count will increase by 1 at each node up the tree, 1197 * but its more complicated for the recursive/multiple snapshot case. 1198 * 1199 * The dsl_fs_ss_limit_check function does recursively check the count 1200 * at each level up the tree but since it is validating each snapshot 1201 * independently we need to be sure that we are validating the complete 1202 * count for the entire set of snapshots. We do this by rolling up the 1203 * counts for each component of the name into an nvlist and then 1204 * checking each of those cases with the aggregated count. 1205 * 1206 * This approach properly handles not only the recursive snapshot 1207 * case (where we get all of those on the ddsa_snaps list) but also 1208 * the sibling case (e.g. snapshot a/b and a/c so that we will also 1209 * validate the limit on 'a' using a count of 2). 1210 * 1211 * We validate the snapshot names in the third loop and only report 1212 * name errors once. 1213 */ 1214 if (dmu_tx_is_syncing(tx)) { 1215 nvlist_t *cnt_track = NULL; 1216 cnt_track = fnvlist_alloc(); 1217 1218 /* Rollup aggregated counts into the cnt_track list */ 1219 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1220 pair != NULL; 1221 pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1222 char *pdelim; 1223 uint64_t val; 1224 char nm[MAXPATHLEN]; 1225 1226 (void) strlcpy(nm, nvpair_name(pair), sizeof (nm)); 1227 pdelim = strchr(nm, '@'); 1228 if (pdelim == NULL) 1229 continue; 1230 *pdelim = '\0'; 1231 1232 do { 1233 if (nvlist_lookup_uint64(cnt_track, nm, 1234 &val) == 0) { 1235 /* update existing entry */ 1236 fnvlist_add_uint64(cnt_track, nm, 1237 val + 1); 1238 } else { 1239 /* add to list */ 1240 fnvlist_add_uint64(cnt_track, nm, 1); 1241 } 1242 1243 pdelim = strrchr(nm, '/'); 1244 if (pdelim != NULL) 1245 *pdelim = '\0'; 1246 } while (pdelim != NULL); 1247 } 1248 1249 /* Check aggregated counts at each level */ 1250 for (pair = nvlist_next_nvpair(cnt_track, NULL); 1251 pair != NULL; pair = nvlist_next_nvpair(cnt_track, pair)) { 1252 int error = 0; 1253 char *name; 1254 uint64_t cnt = 0; 1255 dsl_dataset_t *ds; 1256 1257 name = nvpair_name(pair); 1258 cnt = fnvpair_value_uint64(pair); 1259 ASSERT(cnt > 0); 1260 1261 error = dsl_dataset_hold(dp, name, FTAG, &ds); 1262 if (error == 0) { 1263 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1264 ZFS_PROP_SNAPSHOT_LIMIT, NULL, 1265 ddsa->ddsa_cr); 1266 dsl_dataset_rele(ds, FTAG); 1267 } 1268 1269 if (error != 0) { 1270 if (ddsa->ddsa_errors != NULL) 1271 fnvlist_add_int32(ddsa->ddsa_errors, 1272 name, error); 1273 rv = error; 1274 /* only report one error for this check */ 1275 break; 1276 } 1277 } 1278 nvlist_free(cnt_track); 1279 } 1280 1281 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1282 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1283 int error = 0; 1284 dsl_dataset_t *ds; 1285 char *name, *atp; 1286 char dsname[ZFS_MAX_DATASET_NAME_LEN]; 1287 1288 name = nvpair_name(pair); 1289 if (strlen(name) >= ZFS_MAX_DATASET_NAME_LEN) 1290 error = SET_ERROR(ENAMETOOLONG); 1291 if (error == 0) { 1292 atp = strchr(name, '@'); 1293 if (atp == NULL) 1294 error = SET_ERROR(EINVAL); 1295 if (error == 0) 1296 (void) strlcpy(dsname, name, atp - name + 1); 1297 } 1298 if (error == 0) 1299 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1300 if (error == 0) { 1301 /* passing 0/NULL skips dsl_fs_ss_limit_check */ 1302 error = dsl_dataset_snapshot_check_impl(ds, 1303 atp + 1, tx, B_FALSE, 0, NULL); 1304 dsl_dataset_rele(ds, FTAG); 1305 } 1306 1307 if (error != 0) { 1308 if (ddsa->ddsa_errors != NULL) { 1309 fnvlist_add_int32(ddsa->ddsa_errors, 1310 name, error); 1311 } 1312 rv = error; 1313 } 1314 } 1315 1316 return (rv); 1317 } 1318 1319 void 1320 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1321 dmu_tx_t *tx) 1322 { 1323 static zil_header_t zero_zil; 1324 1325 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1326 dmu_buf_t *dbuf; 1327 dsl_dataset_phys_t *dsphys; 1328 uint64_t dsobj, crtxg; 1329 objset_t *mos = dp->dp_meta_objset; 1330 objset_t *os; 1331 1332 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1333 1334 /* 1335 * If we are on an old pool, the zil must not be active, in which 1336 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1337 */ 1338 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1339 dmu_objset_from_ds(ds, &os) != 0 || 1340 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1341 sizeof (zero_zil)) == 0); 1342 1343 dsl_fs_ss_count_adjust(ds->ds_dir, 1, DD_FIELD_SNAPSHOT_COUNT, tx); 1344 1345 /* 1346 * The origin's ds_creation_txg has to be < TXG_INITIAL 1347 */ 1348 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1349 crtxg = 1; 1350 else 1351 crtxg = tx->tx_txg; 1352 1353 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1354 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1355 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1356 dmu_buf_will_dirty(dbuf, tx); 1357 dsphys = dbuf->db_data; 1358 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1359 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1360 dsphys->ds_fsid_guid = unique_create(); 1361 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1362 sizeof (dsphys->ds_guid)); 1363 dsphys->ds_prev_snap_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 1364 dsphys->ds_prev_snap_txg = dsl_dataset_phys(ds)->ds_prev_snap_txg; 1365 dsphys->ds_next_snap_obj = ds->ds_object; 1366 dsphys->ds_num_children = 1; 1367 dsphys->ds_creation_time = gethrestime_sec(); 1368 dsphys->ds_creation_txg = crtxg; 1369 dsphys->ds_deadlist_obj = dsl_dataset_phys(ds)->ds_deadlist_obj; 1370 dsphys->ds_referenced_bytes = dsl_dataset_phys(ds)->ds_referenced_bytes; 1371 dsphys->ds_compressed_bytes = dsl_dataset_phys(ds)->ds_compressed_bytes; 1372 dsphys->ds_uncompressed_bytes = 1373 dsl_dataset_phys(ds)->ds_uncompressed_bytes; 1374 dsphys->ds_flags = dsl_dataset_phys(ds)->ds_flags; 1375 dsphys->ds_bp = dsl_dataset_phys(ds)->ds_bp; 1376 dmu_buf_rele(dbuf, FTAG); 1377 1378 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1379 if (ds->ds_feature_inuse[f]) 1380 dsl_dataset_activate_feature(dsobj, f, tx); 1381 } 1382 1383 ASSERT3U(ds->ds_prev != 0, ==, 1384 dsl_dataset_phys(ds)->ds_prev_snap_obj != 0); 1385 if (ds->ds_prev) { 1386 uint64_t next_clones_obj = 1387 dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj; 1388 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1389 ds->ds_object || 1390 dsl_dataset_phys(ds->ds_prev)->ds_num_children > 1); 1391 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1392 ds->ds_object) { 1393 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1394 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==, 1395 dsl_dataset_phys(ds->ds_prev)->ds_creation_txg); 1396 dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj = dsobj; 1397 } else if (next_clones_obj != 0) { 1398 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1399 dsphys->ds_next_snap_obj, tx); 1400 VERIFY0(zap_add_int(mos, 1401 next_clones_obj, dsobj, tx)); 1402 } 1403 } 1404 1405 /* 1406 * If we have a reference-reservation on this dataset, we will 1407 * need to increase the amount of refreservation being charged 1408 * since our unique space is going to zero. 1409 */ 1410 if (ds->ds_reserved) { 1411 int64_t delta; 1412 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1413 delta = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, 1414 ds->ds_reserved); 1415 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1416 delta, 0, 0, tx); 1417 } 1418 1419 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1420 dsl_dataset_phys(ds)->ds_deadlist_obj = 1421 dsl_deadlist_clone(&ds->ds_deadlist, UINT64_MAX, 1422 dsl_dataset_phys(ds)->ds_prev_snap_obj, tx); 1423 dsl_deadlist_close(&ds->ds_deadlist); 1424 dsl_deadlist_open(&ds->ds_deadlist, mos, 1425 dsl_dataset_phys(ds)->ds_deadlist_obj); 1426 dsl_deadlist_add_key(&ds->ds_deadlist, 1427 dsl_dataset_phys(ds)->ds_prev_snap_txg, tx); 1428 1429 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, <, tx->tx_txg); 1430 dsl_dataset_phys(ds)->ds_prev_snap_obj = dsobj; 1431 dsl_dataset_phys(ds)->ds_prev_snap_txg = crtxg; 1432 dsl_dataset_phys(ds)->ds_unique_bytes = 0; 1433 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1434 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1435 1436 VERIFY0(zap_add(mos, dsl_dataset_phys(ds)->ds_snapnames_zapobj, 1437 snapname, 8, 1, &dsobj, tx)); 1438 1439 if (ds->ds_prev) 1440 dsl_dataset_rele(ds->ds_prev, ds); 1441 VERIFY0(dsl_dataset_hold_obj(dp, 1442 dsl_dataset_phys(ds)->ds_prev_snap_obj, ds, &ds->ds_prev)); 1443 1444 dsl_scan_ds_snapshotted(ds, tx); 1445 1446 dsl_dir_snap_cmtime_update(ds->ds_dir); 1447 1448 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1449 } 1450 1451 static void 1452 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1453 { 1454 dsl_dataset_snapshot_arg_t *ddsa = arg; 1455 dsl_pool_t *dp = dmu_tx_pool(tx); 1456 nvpair_t *pair; 1457 1458 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1459 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1460 dsl_dataset_t *ds; 1461 char *name, *atp; 1462 char dsname[ZFS_MAX_DATASET_NAME_LEN]; 1463 1464 name = nvpair_name(pair); 1465 atp = strchr(name, '@'); 1466 (void) strlcpy(dsname, name, atp - name + 1); 1467 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1468 1469 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1470 if (ddsa->ddsa_props != NULL) { 1471 dsl_props_set_sync_impl(ds->ds_prev, 1472 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1473 } 1474 dsl_dataset_rele(ds, FTAG); 1475 } 1476 } 1477 1478 /* 1479 * The snapshots must all be in the same pool. 1480 * All-or-nothing: if there are any failures, nothing will be modified. 1481 */ 1482 int 1483 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1484 { 1485 dsl_dataset_snapshot_arg_t ddsa; 1486 nvpair_t *pair; 1487 boolean_t needsuspend; 1488 int error; 1489 spa_t *spa; 1490 char *firstname; 1491 nvlist_t *suspended = NULL; 1492 1493 pair = nvlist_next_nvpair(snaps, NULL); 1494 if (pair == NULL) 1495 return (0); 1496 firstname = nvpair_name(pair); 1497 1498 error = spa_open(firstname, &spa, FTAG); 1499 if (error != 0) 1500 return (error); 1501 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1502 spa_close(spa, FTAG); 1503 1504 if (needsuspend) { 1505 suspended = fnvlist_alloc(); 1506 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1507 pair = nvlist_next_nvpair(snaps, pair)) { 1508 char fsname[ZFS_MAX_DATASET_NAME_LEN]; 1509 char *snapname = nvpair_name(pair); 1510 char *atp; 1511 void *cookie; 1512 1513 atp = strchr(snapname, '@'); 1514 if (atp == NULL) { 1515 error = SET_ERROR(EINVAL); 1516 break; 1517 } 1518 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1519 1520 error = zil_suspend(fsname, &cookie); 1521 if (error != 0) 1522 break; 1523 fnvlist_add_uint64(suspended, fsname, 1524 (uintptr_t)cookie); 1525 } 1526 } 1527 1528 ddsa.ddsa_snaps = snaps; 1529 ddsa.ddsa_props = props; 1530 ddsa.ddsa_errors = errors; 1531 ddsa.ddsa_cr = CRED(); 1532 1533 if (error == 0) { 1534 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1535 dsl_dataset_snapshot_sync, &ddsa, 1536 fnvlist_num_pairs(snaps) * 3, ZFS_SPACE_CHECK_NORMAL); 1537 } 1538 1539 if (suspended != NULL) { 1540 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1541 pair = nvlist_next_nvpair(suspended, pair)) { 1542 zil_resume((void *)(uintptr_t) 1543 fnvpair_value_uint64(pair)); 1544 } 1545 fnvlist_free(suspended); 1546 } 1547 1548 return (error); 1549 } 1550 1551 typedef struct dsl_dataset_snapshot_tmp_arg { 1552 const char *ddsta_fsname; 1553 const char *ddsta_snapname; 1554 minor_t ddsta_cleanup_minor; 1555 const char *ddsta_htag; 1556 } dsl_dataset_snapshot_tmp_arg_t; 1557 1558 static int 1559 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1560 { 1561 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1562 dsl_pool_t *dp = dmu_tx_pool(tx); 1563 dsl_dataset_t *ds; 1564 int error; 1565 1566 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1567 if (error != 0) 1568 return (error); 1569 1570 /* NULL cred means no limit check for tmp snapshot */ 1571 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1572 tx, B_FALSE, 0, NULL); 1573 if (error != 0) { 1574 dsl_dataset_rele(ds, FTAG); 1575 return (error); 1576 } 1577 1578 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1579 dsl_dataset_rele(ds, FTAG); 1580 return (SET_ERROR(ENOTSUP)); 1581 } 1582 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1583 B_TRUE, tx); 1584 if (error != 0) { 1585 dsl_dataset_rele(ds, FTAG); 1586 return (error); 1587 } 1588 1589 dsl_dataset_rele(ds, FTAG); 1590 return (0); 1591 } 1592 1593 static void 1594 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1595 { 1596 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1597 dsl_pool_t *dp = dmu_tx_pool(tx); 1598 dsl_dataset_t *ds; 1599 1600 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1601 1602 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1603 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1604 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1605 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1606 1607 dsl_dataset_rele(ds, FTAG); 1608 } 1609 1610 int 1611 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1612 minor_t cleanup_minor, const char *htag) 1613 { 1614 dsl_dataset_snapshot_tmp_arg_t ddsta; 1615 int error; 1616 spa_t *spa; 1617 boolean_t needsuspend; 1618 void *cookie; 1619 1620 ddsta.ddsta_fsname = fsname; 1621 ddsta.ddsta_snapname = snapname; 1622 ddsta.ddsta_cleanup_minor = cleanup_minor; 1623 ddsta.ddsta_htag = htag; 1624 1625 error = spa_open(fsname, &spa, FTAG); 1626 if (error != 0) 1627 return (error); 1628 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1629 spa_close(spa, FTAG); 1630 1631 if (needsuspend) { 1632 error = zil_suspend(fsname, &cookie); 1633 if (error != 0) 1634 return (error); 1635 } 1636 1637 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1638 dsl_dataset_snapshot_tmp_sync, &ddsta, 3, ZFS_SPACE_CHECK_RESERVED); 1639 1640 if (needsuspend) 1641 zil_resume(cookie); 1642 return (error); 1643 } 1644 1645 1646 void 1647 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1648 { 1649 ASSERT(dmu_tx_is_syncing(tx)); 1650 ASSERT(ds->ds_objset != NULL); 1651 ASSERT(dsl_dataset_phys(ds)->ds_next_snap_obj == 0); 1652 1653 /* 1654 * in case we had to change ds_fsid_guid when we opened it, 1655 * sync it out now. 1656 */ 1657 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1658 dsl_dataset_phys(ds)->ds_fsid_guid = ds->ds_fsid_guid; 1659 1660 if (ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] != 0) { 1661 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1662 ds->ds_object, DS_FIELD_RESUME_OBJECT, 8, 1, 1663 &ds->ds_resume_object[tx->tx_txg & TXG_MASK], tx)); 1664 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1665 ds->ds_object, DS_FIELD_RESUME_OFFSET, 8, 1, 1666 &ds->ds_resume_offset[tx->tx_txg & TXG_MASK], tx)); 1667 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1668 ds->ds_object, DS_FIELD_RESUME_BYTES, 8, 1, 1669 &ds->ds_resume_bytes[tx->tx_txg & TXG_MASK], tx)); 1670 ds->ds_resume_object[tx->tx_txg & TXG_MASK] = 0; 1671 ds->ds_resume_offset[tx->tx_txg & TXG_MASK] = 0; 1672 ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] = 0; 1673 } 1674 1675 dmu_objset_sync(ds->ds_objset, zio, tx); 1676 1677 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1678 if (ds->ds_feature_activation_needed[f]) { 1679 if (ds->ds_feature_inuse[f]) 1680 continue; 1681 dsl_dataset_activate_feature(ds->ds_object, f, tx); 1682 ds->ds_feature_inuse[f] = B_TRUE; 1683 } 1684 } 1685 } 1686 1687 static void 1688 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1689 { 1690 uint64_t count = 0; 1691 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1692 zap_cursor_t zc; 1693 zap_attribute_t za; 1694 nvlist_t *propval = fnvlist_alloc(); 1695 nvlist_t *val = fnvlist_alloc(); 1696 1697 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1698 1699 /* 1700 * There may be missing entries in ds_next_clones_obj 1701 * due to a bug in a previous version of the code. 1702 * Only trust it if it has the right number of entries. 1703 */ 1704 if (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) { 1705 VERIFY0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1706 &count)); 1707 } 1708 if (count != dsl_dataset_phys(ds)->ds_num_children - 1) 1709 goto fail; 1710 for (zap_cursor_init(&zc, mos, 1711 dsl_dataset_phys(ds)->ds_next_clones_obj); 1712 zap_cursor_retrieve(&zc, &za) == 0; 1713 zap_cursor_advance(&zc)) { 1714 dsl_dataset_t *clone; 1715 char buf[ZFS_MAX_DATASET_NAME_LEN]; 1716 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1717 za.za_first_integer, FTAG, &clone)); 1718 dsl_dir_name(clone->ds_dir, buf); 1719 fnvlist_add_boolean(val, buf); 1720 dsl_dataset_rele(clone, FTAG); 1721 } 1722 zap_cursor_fini(&zc); 1723 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1724 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1725 fail: 1726 nvlist_free(val); 1727 nvlist_free(propval); 1728 } 1729 1730 static void 1731 get_receive_resume_stats(dsl_dataset_t *ds, nvlist_t *nv) 1732 { 1733 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1734 1735 if (dsl_dataset_has_resume_receive_state(ds)) { 1736 char *str; 1737 void *packed; 1738 uint8_t *compressed; 1739 uint64_t val; 1740 nvlist_t *token_nv = fnvlist_alloc(); 1741 size_t packed_size, compressed_size; 1742 1743 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1744 DS_FIELD_RESUME_FROMGUID, sizeof (val), 1, &val) == 0) { 1745 fnvlist_add_uint64(token_nv, "fromguid", val); 1746 } 1747 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1748 DS_FIELD_RESUME_OBJECT, sizeof (val), 1, &val) == 0) { 1749 fnvlist_add_uint64(token_nv, "object", val); 1750 } 1751 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1752 DS_FIELD_RESUME_OFFSET, sizeof (val), 1, &val) == 0) { 1753 fnvlist_add_uint64(token_nv, "offset", val); 1754 } 1755 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1756 DS_FIELD_RESUME_BYTES, sizeof (val), 1, &val) == 0) { 1757 fnvlist_add_uint64(token_nv, "bytes", val); 1758 } 1759 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1760 DS_FIELD_RESUME_TOGUID, sizeof (val), 1, &val) == 0) { 1761 fnvlist_add_uint64(token_nv, "toguid", val); 1762 } 1763 char buf[256]; 1764 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1765 DS_FIELD_RESUME_TONAME, 1, sizeof (buf), buf) == 0) { 1766 fnvlist_add_string(token_nv, "toname", buf); 1767 } 1768 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1769 DS_FIELD_RESUME_EMBEDOK) == 0) { 1770 fnvlist_add_boolean(token_nv, "embedok"); 1771 } 1772 packed = fnvlist_pack(token_nv, &packed_size); 1773 fnvlist_free(token_nv); 1774 compressed = kmem_alloc(packed_size, KM_SLEEP); 1775 1776 compressed_size = gzip_compress(packed, compressed, 1777 packed_size, packed_size, 6); 1778 1779 zio_cksum_t cksum; 1780 fletcher_4_native(compressed, compressed_size, NULL, &cksum); 1781 1782 str = kmem_alloc(compressed_size * 2 + 1, KM_SLEEP); 1783 for (int i = 0; i < compressed_size; i++) { 1784 (void) sprintf(str + i * 2, "%02x", compressed[i]); 1785 } 1786 str[compressed_size * 2] = '\0'; 1787 char *propval = kmem_asprintf("%u-%llx-%llx-%s", 1788 ZFS_SEND_RESUME_TOKEN_VERSION, 1789 (longlong_t)cksum.zc_word[0], 1790 (longlong_t)packed_size, str); 1791 dsl_prop_nvlist_add_string(nv, 1792 ZFS_PROP_RECEIVE_RESUME_TOKEN, propval); 1793 kmem_free(packed, packed_size); 1794 kmem_free(str, compressed_size * 2 + 1); 1795 kmem_free(compressed, packed_size); 1796 strfree(propval); 1797 } 1798 } 1799 1800 void 1801 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1802 { 1803 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1804 uint64_t refd, avail, uobjs, aobjs, ratio; 1805 1806 ASSERT(dsl_pool_config_held(dp)); 1807 1808 ratio = dsl_dataset_phys(ds)->ds_compressed_bytes == 0 ? 100 : 1809 (dsl_dataset_phys(ds)->ds_uncompressed_bytes * 100 / 1810 dsl_dataset_phys(ds)->ds_compressed_bytes); 1811 1812 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1813 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1814 dsl_dataset_phys(ds)->ds_uncompressed_bytes); 1815 1816 if (ds->ds_is_snapshot) { 1817 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1818 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1819 dsl_dataset_phys(ds)->ds_unique_bytes); 1820 get_clones_stat(ds, nv); 1821 } else { 1822 if (ds->ds_prev != NULL && ds->ds_prev != dp->dp_origin_snap) { 1823 char buf[ZFS_MAX_DATASET_NAME_LEN]; 1824 dsl_dataset_name(ds->ds_prev, buf); 1825 dsl_prop_nvlist_add_string(nv, ZFS_PROP_PREV_SNAP, buf); 1826 } 1827 1828 dsl_dir_stats(ds->ds_dir, nv); 1829 } 1830 1831 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1832 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1833 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1834 1835 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1836 dsl_dataset_phys(ds)->ds_creation_time); 1837 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1838 dsl_dataset_phys(ds)->ds_creation_txg); 1839 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1840 ds->ds_quota); 1841 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1842 ds->ds_reserved); 1843 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1844 dsl_dataset_phys(ds)->ds_guid); 1845 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1846 dsl_dataset_phys(ds)->ds_unique_bytes); 1847 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1848 ds->ds_object); 1849 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1850 ds->ds_userrefs); 1851 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1852 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1853 1854 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 1855 uint64_t written, comp, uncomp; 1856 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1857 dsl_dataset_t *prev; 1858 1859 int err = dsl_dataset_hold_obj(dp, 1860 dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &prev); 1861 if (err == 0) { 1862 err = dsl_dataset_space_written(prev, ds, &written, 1863 &comp, &uncomp); 1864 dsl_dataset_rele(prev, FTAG); 1865 if (err == 0) { 1866 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1867 written); 1868 } 1869 } 1870 } 1871 1872 if (!dsl_dataset_is_snapshot(ds)) { 1873 /* 1874 * A failed "newfs" (e.g. full) resumable receive leaves 1875 * the stats set on this dataset. Check here for the prop. 1876 */ 1877 get_receive_resume_stats(ds, nv); 1878 1879 /* 1880 * A failed incremental resumable receive leaves the 1881 * stats set on our child named "%recv". Check the child 1882 * for the prop. 1883 */ 1884 /* 6 extra bytes for /%recv */ 1885 char recvname[ZFS_MAX_DATASET_NAME_LEN + 6]; 1886 dsl_dataset_t *recv_ds; 1887 dsl_dataset_name(ds, recvname); 1888 if (strlcat(recvname, "/", sizeof (recvname)) < 1889 sizeof (recvname) && 1890 strlcat(recvname, recv_clone_name, sizeof (recvname)) < 1891 sizeof (recvname) && 1892 dsl_dataset_hold(dp, recvname, FTAG, &recv_ds) == 0) { 1893 get_receive_resume_stats(recv_ds, nv); 1894 dsl_dataset_rele(recv_ds, FTAG); 1895 } 1896 } 1897 } 1898 1899 void 1900 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1901 { 1902 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1903 ASSERT(dsl_pool_config_held(dp)); 1904 1905 stat->dds_creation_txg = dsl_dataset_phys(ds)->ds_creation_txg; 1906 stat->dds_inconsistent = 1907 dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT; 1908 stat->dds_guid = dsl_dataset_phys(ds)->ds_guid; 1909 stat->dds_origin[0] = '\0'; 1910 if (ds->ds_is_snapshot) { 1911 stat->dds_is_snapshot = B_TRUE; 1912 stat->dds_num_clones = 1913 dsl_dataset_phys(ds)->ds_num_children - 1; 1914 } else { 1915 stat->dds_is_snapshot = B_FALSE; 1916 stat->dds_num_clones = 0; 1917 1918 if (dsl_dir_is_clone(ds->ds_dir)) { 1919 dsl_dataset_t *ods; 1920 1921 VERIFY0(dsl_dataset_hold_obj(dp, 1922 dsl_dir_phys(ds->ds_dir)->dd_origin_obj, 1923 FTAG, &ods)); 1924 dsl_dataset_name(ods, stat->dds_origin); 1925 dsl_dataset_rele(ods, FTAG); 1926 } 1927 } 1928 } 1929 1930 uint64_t 1931 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1932 { 1933 return (ds->ds_fsid_guid); 1934 } 1935 1936 void 1937 dsl_dataset_space(dsl_dataset_t *ds, 1938 uint64_t *refdbytesp, uint64_t *availbytesp, 1939 uint64_t *usedobjsp, uint64_t *availobjsp) 1940 { 1941 *refdbytesp = dsl_dataset_phys(ds)->ds_referenced_bytes; 1942 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1943 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) 1944 *availbytesp += 1945 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes; 1946 if (ds->ds_quota != 0) { 1947 /* 1948 * Adjust available bytes according to refquota 1949 */ 1950 if (*refdbytesp < ds->ds_quota) 1951 *availbytesp = MIN(*availbytesp, 1952 ds->ds_quota - *refdbytesp); 1953 else 1954 *availbytesp = 0; 1955 } 1956 *usedobjsp = BP_GET_FILL(&dsl_dataset_phys(ds)->ds_bp); 1957 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1958 } 1959 1960 boolean_t 1961 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1962 { 1963 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1964 1965 ASSERT(dsl_pool_config_held(dp)); 1966 if (snap == NULL) 1967 return (B_FALSE); 1968 if (dsl_dataset_phys(ds)->ds_bp.blk_birth > 1969 dsl_dataset_phys(snap)->ds_creation_txg) { 1970 objset_t *os, *os_snap; 1971 /* 1972 * It may be that only the ZIL differs, because it was 1973 * reset in the head. Don't count that as being 1974 * modified. 1975 */ 1976 if (dmu_objset_from_ds(ds, &os) != 0) 1977 return (B_TRUE); 1978 if (dmu_objset_from_ds(snap, &os_snap) != 0) 1979 return (B_TRUE); 1980 return (bcmp(&os->os_phys->os_meta_dnode, 1981 &os_snap->os_phys->os_meta_dnode, 1982 sizeof (os->os_phys->os_meta_dnode)) != 0); 1983 } 1984 return (B_FALSE); 1985 } 1986 1987 typedef struct dsl_dataset_rename_snapshot_arg { 1988 const char *ddrsa_fsname; 1989 const char *ddrsa_oldsnapname; 1990 const char *ddrsa_newsnapname; 1991 boolean_t ddrsa_recursive; 1992 dmu_tx_t *ddrsa_tx; 1993 } dsl_dataset_rename_snapshot_arg_t; 1994 1995 /* ARGSUSED */ 1996 static int 1997 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1998 dsl_dataset_t *hds, void *arg) 1999 { 2000 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2001 int error; 2002 uint64_t val; 2003 2004 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2005 if (error != 0) { 2006 /* ignore nonexistent snapshots */ 2007 return (error == ENOENT ? 0 : error); 2008 } 2009 2010 /* new name should not exist */ 2011 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 2012 if (error == 0) 2013 error = SET_ERROR(EEXIST); 2014 else if (error == ENOENT) 2015 error = 0; 2016 2017 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2018 if (dsl_dir_namelen(hds->ds_dir) + 1 + 2019 strlen(ddrsa->ddrsa_newsnapname) >= ZFS_MAX_DATASET_NAME_LEN) 2020 error = SET_ERROR(ENAMETOOLONG); 2021 2022 return (error); 2023 } 2024 2025 static int 2026 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 2027 { 2028 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2029 dsl_pool_t *dp = dmu_tx_pool(tx); 2030 dsl_dataset_t *hds; 2031 int error; 2032 2033 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 2034 if (error != 0) 2035 return (error); 2036 2037 if (ddrsa->ddrsa_recursive) { 2038 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2039 dsl_dataset_rename_snapshot_check_impl, ddrsa, 2040 DS_FIND_CHILDREN); 2041 } else { 2042 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 2043 } 2044 dsl_dataset_rele(hds, FTAG); 2045 return (error); 2046 } 2047 2048 static int 2049 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 2050 dsl_dataset_t *hds, void *arg) 2051 { 2052 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2053 dsl_dataset_t *ds; 2054 uint64_t val; 2055 dmu_tx_t *tx = ddrsa->ddrsa_tx; 2056 int error; 2057 2058 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2059 ASSERT(error == 0 || error == ENOENT); 2060 if (error == ENOENT) { 2061 /* ignore nonexistent snapshots */ 2062 return (0); 2063 } 2064 2065 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 2066 2067 /* log before we change the name */ 2068 spa_history_log_internal_ds(ds, "rename", tx, 2069 "-> @%s", ddrsa->ddrsa_newsnapname); 2070 2071 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx, 2072 B_FALSE)); 2073 mutex_enter(&ds->ds_lock); 2074 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 2075 mutex_exit(&ds->ds_lock); 2076 VERIFY0(zap_add(dp->dp_meta_objset, 2077 dsl_dataset_phys(hds)->ds_snapnames_zapobj, 2078 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 2079 2080 dsl_dataset_rele(ds, FTAG); 2081 return (0); 2082 } 2083 2084 static void 2085 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 2086 { 2087 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2088 dsl_pool_t *dp = dmu_tx_pool(tx); 2089 dsl_dataset_t *hds; 2090 2091 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 2092 ddrsa->ddrsa_tx = tx; 2093 if (ddrsa->ddrsa_recursive) { 2094 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2095 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 2096 DS_FIND_CHILDREN)); 2097 } else { 2098 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 2099 } 2100 dsl_dataset_rele(hds, FTAG); 2101 } 2102 2103 int 2104 dsl_dataset_rename_snapshot(const char *fsname, 2105 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 2106 { 2107 dsl_dataset_rename_snapshot_arg_t ddrsa; 2108 2109 ddrsa.ddrsa_fsname = fsname; 2110 ddrsa.ddrsa_oldsnapname = oldsnapname; 2111 ddrsa.ddrsa_newsnapname = newsnapname; 2112 ddrsa.ddrsa_recursive = recursive; 2113 2114 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 2115 dsl_dataset_rename_snapshot_sync, &ddrsa, 2116 1, ZFS_SPACE_CHECK_RESERVED)); 2117 } 2118 2119 /* 2120 * If we're doing an ownership handoff, we need to make sure that there is 2121 * only one long hold on the dataset. We're not allowed to change anything here 2122 * so we don't permanently release the long hold or regular hold here. We want 2123 * to do this only when syncing to avoid the dataset unexpectedly going away 2124 * when we release the long hold. 2125 */ 2126 static int 2127 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 2128 { 2129 boolean_t held; 2130 2131 if (!dmu_tx_is_syncing(tx)) 2132 return (0); 2133 2134 if (owner != NULL) { 2135 VERIFY3P(ds->ds_owner, ==, owner); 2136 dsl_dataset_long_rele(ds, owner); 2137 } 2138 2139 held = dsl_dataset_long_held(ds); 2140 2141 if (owner != NULL) 2142 dsl_dataset_long_hold(ds, owner); 2143 2144 if (held) 2145 return (SET_ERROR(EBUSY)); 2146 2147 return (0); 2148 } 2149 2150 typedef struct dsl_dataset_rollback_arg { 2151 const char *ddra_fsname; 2152 void *ddra_owner; 2153 nvlist_t *ddra_result; 2154 } dsl_dataset_rollback_arg_t; 2155 2156 static int 2157 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 2158 { 2159 dsl_dataset_rollback_arg_t *ddra = arg; 2160 dsl_pool_t *dp = dmu_tx_pool(tx); 2161 dsl_dataset_t *ds; 2162 int64_t unused_refres_delta; 2163 int error; 2164 2165 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 2166 if (error != 0) 2167 return (error); 2168 2169 /* must not be a snapshot */ 2170 if (ds->ds_is_snapshot) { 2171 dsl_dataset_rele(ds, FTAG); 2172 return (SET_ERROR(EINVAL)); 2173 } 2174 2175 /* must have a most recent snapshot */ 2176 if (dsl_dataset_phys(ds)->ds_prev_snap_txg < TXG_INITIAL) { 2177 dsl_dataset_rele(ds, FTAG); 2178 return (SET_ERROR(EINVAL)); 2179 } 2180 2181 /* must not have any bookmarks after the most recent snapshot */ 2182 nvlist_t *proprequest = fnvlist_alloc(); 2183 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2184 nvlist_t *bookmarks = fnvlist_alloc(); 2185 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks); 2186 fnvlist_free(proprequest); 2187 if (error != 0) 2188 return (error); 2189 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL); 2190 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) { 2191 nvlist_t *valuenv = 2192 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair), 2193 zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2194 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value"); 2195 if (createtxg > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 2196 fnvlist_free(bookmarks); 2197 dsl_dataset_rele(ds, FTAG); 2198 return (SET_ERROR(EEXIST)); 2199 } 2200 } 2201 fnvlist_free(bookmarks); 2202 2203 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 2204 if (error != 0) { 2205 dsl_dataset_rele(ds, FTAG); 2206 return (error); 2207 } 2208 2209 /* 2210 * Check if the snap we are rolling back to uses more than 2211 * the refquota. 2212 */ 2213 if (ds->ds_quota != 0 && 2214 dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes > ds->ds_quota) { 2215 dsl_dataset_rele(ds, FTAG); 2216 return (SET_ERROR(EDQUOT)); 2217 } 2218 2219 /* 2220 * When we do the clone swap, we will temporarily use more space 2221 * due to the refreservation (the head will no longer have any 2222 * unique space, so the entire amount of the refreservation will need 2223 * to be free). We will immediately destroy the clone, freeing 2224 * this space, but the freeing happens over many txg's. 2225 */ 2226 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 2227 dsl_dataset_phys(ds)->ds_unique_bytes); 2228 2229 if (unused_refres_delta > 0 && 2230 unused_refres_delta > 2231 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 2232 dsl_dataset_rele(ds, FTAG); 2233 return (SET_ERROR(ENOSPC)); 2234 } 2235 2236 dsl_dataset_rele(ds, FTAG); 2237 return (0); 2238 } 2239 2240 static void 2241 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 2242 { 2243 dsl_dataset_rollback_arg_t *ddra = arg; 2244 dsl_pool_t *dp = dmu_tx_pool(tx); 2245 dsl_dataset_t *ds, *clone; 2246 uint64_t cloneobj; 2247 char namebuf[ZFS_MAX_DATASET_NAME_LEN]; 2248 2249 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 2250 2251 dsl_dataset_name(ds->ds_prev, namebuf); 2252 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 2253 2254 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 2255 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 2256 2257 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 2258 2259 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 2260 dsl_dataset_zero_zil(ds, tx); 2261 2262 dsl_destroy_head_sync_impl(clone, tx); 2263 2264 dsl_dataset_rele(clone, FTAG); 2265 dsl_dataset_rele(ds, FTAG); 2266 } 2267 2268 /* 2269 * Rolls back the given filesystem or volume to the most recent snapshot. 2270 * The name of the most recent snapshot will be returned under key "target" 2271 * in the result nvlist. 2272 * 2273 * If owner != NULL: 2274 * - The existing dataset MUST be owned by the specified owner at entry 2275 * - Upon return, dataset will still be held by the same owner, whether we 2276 * succeed or not. 2277 * 2278 * This mode is required any time the existing filesystem is mounted. See 2279 * notes above zfs_suspend_fs() for further details. 2280 */ 2281 int 2282 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result) 2283 { 2284 dsl_dataset_rollback_arg_t ddra; 2285 2286 ddra.ddra_fsname = fsname; 2287 ddra.ddra_owner = owner; 2288 ddra.ddra_result = result; 2289 2290 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 2291 dsl_dataset_rollback_sync, &ddra, 2292 1, ZFS_SPACE_CHECK_RESERVED)); 2293 } 2294 2295 struct promotenode { 2296 list_node_t link; 2297 dsl_dataset_t *ds; 2298 }; 2299 2300 typedef struct dsl_dataset_promote_arg { 2301 const char *ddpa_clonename; 2302 dsl_dataset_t *ddpa_clone; 2303 list_t shared_snaps, origin_snaps, clone_snaps; 2304 dsl_dataset_t *origin_origin; /* origin of the origin */ 2305 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2306 char *err_ds; 2307 cred_t *cr; 2308 } dsl_dataset_promote_arg_t; 2309 2310 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2311 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 2312 void *tag); 2313 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 2314 2315 static int 2316 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 2317 { 2318 dsl_dataset_promote_arg_t *ddpa = arg; 2319 dsl_pool_t *dp = dmu_tx_pool(tx); 2320 dsl_dataset_t *hds; 2321 struct promotenode *snap; 2322 dsl_dataset_t *origin_ds; 2323 int err; 2324 uint64_t unused; 2325 uint64_t ss_mv_cnt; 2326 size_t max_snap_len; 2327 2328 err = promote_hold(ddpa, dp, FTAG); 2329 if (err != 0) 2330 return (err); 2331 2332 hds = ddpa->ddpa_clone; 2333 max_snap_len = MAXNAMELEN - strlen(ddpa->ddpa_clonename) - 1; 2334 2335 if (dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE) { 2336 promote_rele(ddpa, FTAG); 2337 return (SET_ERROR(EXDEV)); 2338 } 2339 2340 /* 2341 * Compute and check the amount of space to transfer. Since this is 2342 * so expensive, don't do the preliminary check. 2343 */ 2344 if (!dmu_tx_is_syncing(tx)) { 2345 promote_rele(ddpa, FTAG); 2346 return (0); 2347 } 2348 2349 snap = list_head(&ddpa->shared_snaps); 2350 origin_ds = snap->ds; 2351 2352 /* compute origin's new unique space */ 2353 snap = list_tail(&ddpa->clone_snaps); 2354 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2355 origin_ds->ds_object); 2356 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2357 dsl_dataset_phys(origin_ds)->ds_prev_snap_txg, UINT64_MAX, 2358 &ddpa->unique, &unused, &unused); 2359 2360 /* 2361 * Walk the snapshots that we are moving 2362 * 2363 * Compute space to transfer. Consider the incremental changes 2364 * to used by each snapshot: 2365 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2366 * So each snapshot gave birth to: 2367 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2368 * So a sequence would look like: 2369 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2370 * Which simplifies to: 2371 * uN + kN + kN-1 + ... + k1 + k0 2372 * Note however, if we stop before we reach the ORIGIN we get: 2373 * uN + kN + kN-1 + ... + kM - uM-1 2374 */ 2375 ss_mv_cnt = 0; 2376 ddpa->used = dsl_dataset_phys(origin_ds)->ds_referenced_bytes; 2377 ddpa->comp = dsl_dataset_phys(origin_ds)->ds_compressed_bytes; 2378 ddpa->uncomp = dsl_dataset_phys(origin_ds)->ds_uncompressed_bytes; 2379 for (snap = list_head(&ddpa->shared_snaps); snap; 2380 snap = list_next(&ddpa->shared_snaps, snap)) { 2381 uint64_t val, dlused, dlcomp, dluncomp; 2382 dsl_dataset_t *ds = snap->ds; 2383 2384 ss_mv_cnt++; 2385 2386 /* 2387 * If there are long holds, we won't be able to evict 2388 * the objset. 2389 */ 2390 if (dsl_dataset_long_held(ds)) { 2391 err = SET_ERROR(EBUSY); 2392 goto out; 2393 } 2394 2395 /* Check that the snapshot name does not conflict */ 2396 VERIFY0(dsl_dataset_get_snapname(ds)); 2397 if (strlen(ds->ds_snapname) >= max_snap_len) { 2398 err = SET_ERROR(ENAMETOOLONG); 2399 goto out; 2400 } 2401 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2402 if (err == 0) { 2403 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 2404 err = SET_ERROR(EEXIST); 2405 goto out; 2406 } 2407 if (err != ENOENT) 2408 goto out; 2409 2410 /* The very first snapshot does not have a deadlist */ 2411 if (dsl_dataset_phys(ds)->ds_prev_snap_obj == 0) 2412 continue; 2413 2414 dsl_deadlist_space(&ds->ds_deadlist, 2415 &dlused, &dlcomp, &dluncomp); 2416 ddpa->used += dlused; 2417 ddpa->comp += dlcomp; 2418 ddpa->uncomp += dluncomp; 2419 } 2420 2421 /* 2422 * If we are a clone of a clone then we never reached ORIGIN, 2423 * so we need to subtract out the clone origin's used space. 2424 */ 2425 if (ddpa->origin_origin) { 2426 ddpa->used -= 2427 dsl_dataset_phys(ddpa->origin_origin)->ds_referenced_bytes; 2428 ddpa->comp -= 2429 dsl_dataset_phys(ddpa->origin_origin)->ds_compressed_bytes; 2430 ddpa->uncomp -= 2431 dsl_dataset_phys(ddpa->origin_origin)-> 2432 ds_uncompressed_bytes; 2433 } 2434 2435 /* Check that there is enough space and limit headroom here */ 2436 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2437 0, ss_mv_cnt, ddpa->used, ddpa->cr); 2438 if (err != 0) 2439 goto out; 2440 2441 /* 2442 * Compute the amounts of space that will be used by snapshots 2443 * after the promotion (for both origin and clone). For each, 2444 * it is the amount of space that will be on all of their 2445 * deadlists (that was not born before their new origin). 2446 */ 2447 if (dsl_dir_phys(hds->ds_dir)->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2448 uint64_t space; 2449 2450 /* 2451 * Note, typically this will not be a clone of a clone, 2452 * so dd_origin_txg will be < TXG_INITIAL, so 2453 * these snaplist_space() -> dsl_deadlist_space_range() 2454 * calls will be fast because they do not have to 2455 * iterate over all bps. 2456 */ 2457 snap = list_head(&ddpa->origin_snaps); 2458 err = snaplist_space(&ddpa->shared_snaps, 2459 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 2460 if (err != 0) 2461 goto out; 2462 2463 err = snaplist_space(&ddpa->clone_snaps, 2464 snap->ds->ds_dir->dd_origin_txg, &space); 2465 if (err != 0) 2466 goto out; 2467 ddpa->cloneusedsnap += space; 2468 } 2469 if (dsl_dir_phys(origin_ds->ds_dir)->dd_flags & 2470 DD_FLAG_USED_BREAKDOWN) { 2471 err = snaplist_space(&ddpa->origin_snaps, 2472 dsl_dataset_phys(origin_ds)->ds_creation_txg, 2473 &ddpa->originusedsnap); 2474 if (err != 0) 2475 goto out; 2476 } 2477 2478 out: 2479 promote_rele(ddpa, FTAG); 2480 return (err); 2481 } 2482 2483 static void 2484 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2485 { 2486 dsl_dataset_promote_arg_t *ddpa = arg; 2487 dsl_pool_t *dp = dmu_tx_pool(tx); 2488 dsl_dataset_t *hds; 2489 struct promotenode *snap; 2490 dsl_dataset_t *origin_ds; 2491 dsl_dataset_t *origin_head; 2492 dsl_dir_t *dd; 2493 dsl_dir_t *odd = NULL; 2494 uint64_t oldnext_obj; 2495 int64_t delta; 2496 2497 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2498 hds = ddpa->ddpa_clone; 2499 2500 ASSERT0(dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE); 2501 2502 snap = list_head(&ddpa->shared_snaps); 2503 origin_ds = snap->ds; 2504 dd = hds->ds_dir; 2505 2506 snap = list_head(&ddpa->origin_snaps); 2507 origin_head = snap->ds; 2508 2509 /* 2510 * We need to explicitly open odd, since origin_ds's dd will be 2511 * changing. 2512 */ 2513 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2514 NULL, FTAG, &odd)); 2515 2516 /* change origin's next snap */ 2517 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2518 oldnext_obj = dsl_dataset_phys(origin_ds)->ds_next_snap_obj; 2519 snap = list_tail(&ddpa->clone_snaps); 2520 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2521 origin_ds->ds_object); 2522 dsl_dataset_phys(origin_ds)->ds_next_snap_obj = snap->ds->ds_object; 2523 2524 /* change the origin's next clone */ 2525 if (dsl_dataset_phys(origin_ds)->ds_next_clones_obj) { 2526 dsl_dataset_remove_from_next_clones(origin_ds, 2527 snap->ds->ds_object, tx); 2528 VERIFY0(zap_add_int(dp->dp_meta_objset, 2529 dsl_dataset_phys(origin_ds)->ds_next_clones_obj, 2530 oldnext_obj, tx)); 2531 } 2532 2533 /* change origin */ 2534 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2535 ASSERT3U(dsl_dir_phys(dd)->dd_origin_obj, ==, origin_ds->ds_object); 2536 dsl_dir_phys(dd)->dd_origin_obj = dsl_dir_phys(odd)->dd_origin_obj; 2537 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2538 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2539 dsl_dir_phys(odd)->dd_origin_obj = origin_ds->ds_object; 2540 origin_head->ds_dir->dd_origin_txg = 2541 dsl_dataset_phys(origin_ds)->ds_creation_txg; 2542 2543 /* change dd_clone entries */ 2544 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2545 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2546 dsl_dir_phys(odd)->dd_clones, hds->ds_object, tx)); 2547 VERIFY0(zap_add_int(dp->dp_meta_objset, 2548 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2549 hds->ds_object, tx)); 2550 2551 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2552 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2553 origin_head->ds_object, tx)); 2554 if (dsl_dir_phys(dd)->dd_clones == 0) { 2555 dsl_dir_phys(dd)->dd_clones = 2556 zap_create(dp->dp_meta_objset, DMU_OT_DSL_CLONES, 2557 DMU_OT_NONE, 0, tx); 2558 } 2559 VERIFY0(zap_add_int(dp->dp_meta_objset, 2560 dsl_dir_phys(dd)->dd_clones, origin_head->ds_object, tx)); 2561 } 2562 2563 /* move snapshots to this dir */ 2564 for (snap = list_head(&ddpa->shared_snaps); snap; 2565 snap = list_next(&ddpa->shared_snaps, snap)) { 2566 dsl_dataset_t *ds = snap->ds; 2567 2568 /* 2569 * Property callbacks are registered to a particular 2570 * dsl_dir. Since ours is changing, evict the objset 2571 * so that they will be unregistered from the old dsl_dir. 2572 */ 2573 if (ds->ds_objset) { 2574 dmu_objset_evict(ds->ds_objset); 2575 ds->ds_objset = NULL; 2576 } 2577 2578 /* move snap name entry */ 2579 VERIFY0(dsl_dataset_get_snapname(ds)); 2580 VERIFY0(dsl_dataset_snap_remove(origin_head, 2581 ds->ds_snapname, tx, B_TRUE)); 2582 VERIFY0(zap_add(dp->dp_meta_objset, 2583 dsl_dataset_phys(hds)->ds_snapnames_zapobj, ds->ds_snapname, 2584 8, 1, &ds->ds_object, tx)); 2585 dsl_fs_ss_count_adjust(hds->ds_dir, 1, 2586 DD_FIELD_SNAPSHOT_COUNT, tx); 2587 2588 /* change containing dsl_dir */ 2589 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2590 ASSERT3U(dsl_dataset_phys(ds)->ds_dir_obj, ==, odd->dd_object); 2591 dsl_dataset_phys(ds)->ds_dir_obj = dd->dd_object; 2592 ASSERT3P(ds->ds_dir, ==, odd); 2593 dsl_dir_rele(ds->ds_dir, ds); 2594 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2595 NULL, ds, &ds->ds_dir)); 2596 2597 /* move any clone references */ 2598 if (dsl_dataset_phys(ds)->ds_next_clones_obj && 2599 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2600 zap_cursor_t zc; 2601 zap_attribute_t za; 2602 2603 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2604 dsl_dataset_phys(ds)->ds_next_clones_obj); 2605 zap_cursor_retrieve(&zc, &za) == 0; 2606 zap_cursor_advance(&zc)) { 2607 dsl_dataset_t *cnds; 2608 uint64_t o; 2609 2610 if (za.za_first_integer == oldnext_obj) { 2611 /* 2612 * We've already moved the 2613 * origin's reference. 2614 */ 2615 continue; 2616 } 2617 2618 VERIFY0(dsl_dataset_hold_obj(dp, 2619 za.za_first_integer, FTAG, &cnds)); 2620 o = dsl_dir_phys(cnds->ds_dir)-> 2621 dd_head_dataset_obj; 2622 2623 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2624 dsl_dir_phys(odd)->dd_clones, o, tx)); 2625 VERIFY0(zap_add_int(dp->dp_meta_objset, 2626 dsl_dir_phys(dd)->dd_clones, o, tx)); 2627 dsl_dataset_rele(cnds, FTAG); 2628 } 2629 zap_cursor_fini(&zc); 2630 } 2631 2632 ASSERT(!dsl_prop_hascb(ds)); 2633 } 2634 2635 /* 2636 * Change space accounting. 2637 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2638 * both be valid, or both be 0 (resulting in delta == 0). This 2639 * is true for each of {clone,origin} independently. 2640 */ 2641 2642 delta = ddpa->cloneusedsnap - 2643 dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_SNAP]; 2644 ASSERT3S(delta, >=, 0); 2645 ASSERT3U(ddpa->used, >=, delta); 2646 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2647 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2648 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2649 2650 delta = ddpa->originusedsnap - 2651 dsl_dir_phys(odd)->dd_used_breakdown[DD_USED_SNAP]; 2652 ASSERT3S(delta, <=, 0); 2653 ASSERT3U(ddpa->used, >=, -delta); 2654 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2655 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2656 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2657 2658 dsl_dataset_phys(origin_ds)->ds_unique_bytes = ddpa->unique; 2659 2660 /* log history record */ 2661 spa_history_log_internal_ds(hds, "promote", tx, ""); 2662 2663 dsl_dir_rele(odd, FTAG); 2664 promote_rele(ddpa, FTAG); 2665 } 2666 2667 /* 2668 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2669 * (exclusive) and last_obj (inclusive). The list will be in reverse 2670 * order (last_obj will be the list_head()). If first_obj == 0, do all 2671 * snapshots back to this dataset's origin. 2672 */ 2673 static int 2674 snaplist_make(dsl_pool_t *dp, 2675 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2676 { 2677 uint64_t obj = last_obj; 2678 2679 list_create(l, sizeof (struct promotenode), 2680 offsetof(struct promotenode, link)); 2681 2682 while (obj != first_obj) { 2683 dsl_dataset_t *ds; 2684 struct promotenode *snap; 2685 int err; 2686 2687 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2688 ASSERT(err != ENOENT); 2689 if (err != 0) 2690 return (err); 2691 2692 if (first_obj == 0) 2693 first_obj = dsl_dir_phys(ds->ds_dir)->dd_origin_obj; 2694 2695 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2696 snap->ds = ds; 2697 list_insert_tail(l, snap); 2698 obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 2699 } 2700 2701 return (0); 2702 } 2703 2704 static int 2705 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2706 { 2707 struct promotenode *snap; 2708 2709 *spacep = 0; 2710 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2711 uint64_t used, comp, uncomp; 2712 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2713 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2714 *spacep += used; 2715 } 2716 return (0); 2717 } 2718 2719 static void 2720 snaplist_destroy(list_t *l, void *tag) 2721 { 2722 struct promotenode *snap; 2723 2724 if (l == NULL || !list_link_active(&l->list_head)) 2725 return; 2726 2727 while ((snap = list_tail(l)) != NULL) { 2728 list_remove(l, snap); 2729 dsl_dataset_rele(snap->ds, tag); 2730 kmem_free(snap, sizeof (*snap)); 2731 } 2732 list_destroy(l); 2733 } 2734 2735 static int 2736 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2737 { 2738 int error; 2739 dsl_dir_t *dd; 2740 struct promotenode *snap; 2741 2742 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2743 &ddpa->ddpa_clone); 2744 if (error != 0) 2745 return (error); 2746 dd = ddpa->ddpa_clone->ds_dir; 2747 2748 if (ddpa->ddpa_clone->ds_is_snapshot || 2749 !dsl_dir_is_clone(dd)) { 2750 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2751 return (SET_ERROR(EINVAL)); 2752 } 2753 2754 error = snaplist_make(dp, 0, dsl_dir_phys(dd)->dd_origin_obj, 2755 &ddpa->shared_snaps, tag); 2756 if (error != 0) 2757 goto out; 2758 2759 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2760 &ddpa->clone_snaps, tag); 2761 if (error != 0) 2762 goto out; 2763 2764 snap = list_head(&ddpa->shared_snaps); 2765 ASSERT3U(snap->ds->ds_object, ==, dsl_dir_phys(dd)->dd_origin_obj); 2766 error = snaplist_make(dp, dsl_dir_phys(dd)->dd_origin_obj, 2767 dsl_dir_phys(snap->ds->ds_dir)->dd_head_dataset_obj, 2768 &ddpa->origin_snaps, tag); 2769 if (error != 0) 2770 goto out; 2771 2772 if (dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj != 0) { 2773 error = dsl_dataset_hold_obj(dp, 2774 dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj, 2775 tag, &ddpa->origin_origin); 2776 if (error != 0) 2777 goto out; 2778 } 2779 out: 2780 if (error != 0) 2781 promote_rele(ddpa, tag); 2782 return (error); 2783 } 2784 2785 static void 2786 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2787 { 2788 snaplist_destroy(&ddpa->shared_snaps, tag); 2789 snaplist_destroy(&ddpa->clone_snaps, tag); 2790 snaplist_destroy(&ddpa->origin_snaps, tag); 2791 if (ddpa->origin_origin != NULL) 2792 dsl_dataset_rele(ddpa->origin_origin, tag); 2793 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2794 } 2795 2796 /* 2797 * Promote a clone. 2798 * 2799 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2800 * in with the name. (It must be at least ZFS_MAX_DATASET_NAME_LEN bytes long.) 2801 */ 2802 int 2803 dsl_dataset_promote(const char *name, char *conflsnap) 2804 { 2805 dsl_dataset_promote_arg_t ddpa = { 0 }; 2806 uint64_t numsnaps; 2807 int error; 2808 objset_t *os; 2809 2810 /* 2811 * We will modify space proportional to the number of 2812 * snapshots. Compute numsnaps. 2813 */ 2814 error = dmu_objset_hold(name, FTAG, &os); 2815 if (error != 0) 2816 return (error); 2817 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2818 dsl_dataset_phys(dmu_objset_ds(os))->ds_snapnames_zapobj, 2819 &numsnaps); 2820 dmu_objset_rele(os, FTAG); 2821 if (error != 0) 2822 return (error); 2823 2824 ddpa.ddpa_clonename = name; 2825 ddpa.err_ds = conflsnap; 2826 ddpa.cr = CRED(); 2827 2828 return (dsl_sync_task(name, dsl_dataset_promote_check, 2829 dsl_dataset_promote_sync, &ddpa, 2830 2 + numsnaps, ZFS_SPACE_CHECK_RESERVED)); 2831 } 2832 2833 int 2834 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2835 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2836 { 2837 /* 2838 * "slack" factor for received datasets with refquota set on them. 2839 * See the bottom of this function for details on its use. 2840 */ 2841 uint64_t refquota_slack = DMU_MAX_ACCESS * spa_asize_inflation; 2842 int64_t unused_refres_delta; 2843 2844 /* they should both be heads */ 2845 if (clone->ds_is_snapshot || 2846 origin_head->ds_is_snapshot) 2847 return (SET_ERROR(EINVAL)); 2848 2849 /* if we are not forcing, the branch point should be just before them */ 2850 if (!force && clone->ds_prev != origin_head->ds_prev) 2851 return (SET_ERROR(EINVAL)); 2852 2853 /* clone should be the clone (unless they are unrelated) */ 2854 if (clone->ds_prev != NULL && 2855 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2856 origin_head->ds_dir != clone->ds_prev->ds_dir) 2857 return (SET_ERROR(EINVAL)); 2858 2859 /* the clone should be a child of the origin */ 2860 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2861 return (SET_ERROR(EINVAL)); 2862 2863 /* origin_head shouldn't be modified unless 'force' */ 2864 if (!force && 2865 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2866 return (SET_ERROR(ETXTBSY)); 2867 2868 /* origin_head should have no long holds (e.g. is not mounted) */ 2869 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2870 return (SET_ERROR(EBUSY)); 2871 2872 /* check amount of any unconsumed refreservation */ 2873 unused_refres_delta = 2874 (int64_t)MIN(origin_head->ds_reserved, 2875 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 2876 (int64_t)MIN(origin_head->ds_reserved, 2877 dsl_dataset_phys(clone)->ds_unique_bytes); 2878 2879 if (unused_refres_delta > 0 && 2880 unused_refres_delta > 2881 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2882 return (SET_ERROR(ENOSPC)); 2883 2884 /* 2885 * The clone can't be too much over the head's refquota. 2886 * 2887 * To ensure that the entire refquota can be used, we allow one 2888 * transaction to exceed the the refquota. Therefore, this check 2889 * needs to also allow for the space referenced to be more than the 2890 * refquota. The maximum amount of space that one transaction can use 2891 * on disk is DMU_MAX_ACCESS * spa_asize_inflation. Allowing this 2892 * overage ensures that we are able to receive a filesystem that 2893 * exceeds the refquota on the source system. 2894 * 2895 * So that overage is the refquota_slack we use below. 2896 */ 2897 if (origin_head->ds_quota != 0 && 2898 dsl_dataset_phys(clone)->ds_referenced_bytes > 2899 origin_head->ds_quota + refquota_slack) 2900 return (SET_ERROR(EDQUOT)); 2901 2902 return (0); 2903 } 2904 2905 void 2906 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2907 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2908 { 2909 dsl_pool_t *dp = dmu_tx_pool(tx); 2910 int64_t unused_refres_delta; 2911 2912 ASSERT(clone->ds_reserved == 0); 2913 /* 2914 * NOTE: On DEBUG kernels there could be a race between this and 2915 * the check function if spa_asize_inflation is adjusted... 2916 */ 2917 ASSERT(origin_head->ds_quota == 0 || 2918 dsl_dataset_phys(clone)->ds_unique_bytes <= origin_head->ds_quota + 2919 DMU_MAX_ACCESS * spa_asize_inflation); 2920 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2921 2922 /* 2923 * Swap per-dataset feature flags. 2924 */ 2925 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 2926 if (!(spa_feature_table[f].fi_flags & 2927 ZFEATURE_FLAG_PER_DATASET)) { 2928 ASSERT(!clone->ds_feature_inuse[f]); 2929 ASSERT(!origin_head->ds_feature_inuse[f]); 2930 continue; 2931 } 2932 2933 boolean_t clone_inuse = clone->ds_feature_inuse[f]; 2934 boolean_t origin_head_inuse = origin_head->ds_feature_inuse[f]; 2935 2936 if (clone_inuse) { 2937 dsl_dataset_deactivate_feature(clone->ds_object, f, tx); 2938 clone->ds_feature_inuse[f] = B_FALSE; 2939 } 2940 if (origin_head_inuse) { 2941 dsl_dataset_deactivate_feature(origin_head->ds_object, 2942 f, tx); 2943 origin_head->ds_feature_inuse[f] = B_FALSE; 2944 } 2945 if (clone_inuse) { 2946 dsl_dataset_activate_feature(origin_head->ds_object, 2947 f, tx); 2948 origin_head->ds_feature_inuse[f] = B_TRUE; 2949 } 2950 if (origin_head_inuse) { 2951 dsl_dataset_activate_feature(clone->ds_object, f, tx); 2952 clone->ds_feature_inuse[f] = B_TRUE; 2953 } 2954 } 2955 2956 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2957 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2958 2959 if (clone->ds_objset != NULL) { 2960 dmu_objset_evict(clone->ds_objset); 2961 clone->ds_objset = NULL; 2962 } 2963 2964 if (origin_head->ds_objset != NULL) { 2965 dmu_objset_evict(origin_head->ds_objset); 2966 origin_head->ds_objset = NULL; 2967 } 2968 2969 unused_refres_delta = 2970 (int64_t)MIN(origin_head->ds_reserved, 2971 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 2972 (int64_t)MIN(origin_head->ds_reserved, 2973 dsl_dataset_phys(clone)->ds_unique_bytes); 2974 2975 /* 2976 * Reset origin's unique bytes, if it exists. 2977 */ 2978 if (clone->ds_prev) { 2979 dsl_dataset_t *origin = clone->ds_prev; 2980 uint64_t comp, uncomp; 2981 2982 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2983 dsl_deadlist_space_range(&clone->ds_deadlist, 2984 dsl_dataset_phys(origin)->ds_prev_snap_txg, UINT64_MAX, 2985 &dsl_dataset_phys(origin)->ds_unique_bytes, &comp, &uncomp); 2986 } 2987 2988 /* swap blkptrs */ 2989 { 2990 blkptr_t tmp; 2991 tmp = dsl_dataset_phys(origin_head)->ds_bp; 2992 dsl_dataset_phys(origin_head)->ds_bp = 2993 dsl_dataset_phys(clone)->ds_bp; 2994 dsl_dataset_phys(clone)->ds_bp = tmp; 2995 } 2996 2997 /* set dd_*_bytes */ 2998 { 2999 int64_t dused, dcomp, duncomp; 3000 uint64_t cdl_used, cdl_comp, cdl_uncomp; 3001 uint64_t odl_used, odl_comp, odl_uncomp; 3002 3003 ASSERT3U(dsl_dir_phys(clone->ds_dir)-> 3004 dd_used_breakdown[DD_USED_SNAP], ==, 0); 3005 3006 dsl_deadlist_space(&clone->ds_deadlist, 3007 &cdl_used, &cdl_comp, &cdl_uncomp); 3008 dsl_deadlist_space(&origin_head->ds_deadlist, 3009 &odl_used, &odl_comp, &odl_uncomp); 3010 3011 dused = dsl_dataset_phys(clone)->ds_referenced_bytes + 3012 cdl_used - 3013 (dsl_dataset_phys(origin_head)->ds_referenced_bytes + 3014 odl_used); 3015 dcomp = dsl_dataset_phys(clone)->ds_compressed_bytes + 3016 cdl_comp - 3017 (dsl_dataset_phys(origin_head)->ds_compressed_bytes + 3018 odl_comp); 3019 duncomp = dsl_dataset_phys(clone)->ds_uncompressed_bytes + 3020 cdl_uncomp - 3021 (dsl_dataset_phys(origin_head)->ds_uncompressed_bytes + 3022 odl_uncomp); 3023 3024 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 3025 dused, dcomp, duncomp, tx); 3026 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 3027 -dused, -dcomp, -duncomp, tx); 3028 3029 /* 3030 * The difference in the space used by snapshots is the 3031 * difference in snapshot space due to the head's 3032 * deadlist (since that's the only thing that's 3033 * changing that affects the snapused). 3034 */ 3035 dsl_deadlist_space_range(&clone->ds_deadlist, 3036 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3037 &cdl_used, &cdl_comp, &cdl_uncomp); 3038 dsl_deadlist_space_range(&origin_head->ds_deadlist, 3039 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3040 &odl_used, &odl_comp, &odl_uncomp); 3041 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 3042 DD_USED_HEAD, DD_USED_SNAP, tx); 3043 } 3044 3045 /* swap ds_*_bytes */ 3046 SWITCH64(dsl_dataset_phys(origin_head)->ds_referenced_bytes, 3047 dsl_dataset_phys(clone)->ds_referenced_bytes); 3048 SWITCH64(dsl_dataset_phys(origin_head)->ds_compressed_bytes, 3049 dsl_dataset_phys(clone)->ds_compressed_bytes); 3050 SWITCH64(dsl_dataset_phys(origin_head)->ds_uncompressed_bytes, 3051 dsl_dataset_phys(clone)->ds_uncompressed_bytes); 3052 SWITCH64(dsl_dataset_phys(origin_head)->ds_unique_bytes, 3053 dsl_dataset_phys(clone)->ds_unique_bytes); 3054 3055 /* apply any parent delta for change in unconsumed refreservation */ 3056 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 3057 unused_refres_delta, 0, 0, tx); 3058 3059 /* 3060 * Swap deadlists. 3061 */ 3062 dsl_deadlist_close(&clone->ds_deadlist); 3063 dsl_deadlist_close(&origin_head->ds_deadlist); 3064 SWITCH64(dsl_dataset_phys(origin_head)->ds_deadlist_obj, 3065 dsl_dataset_phys(clone)->ds_deadlist_obj); 3066 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 3067 dsl_dataset_phys(clone)->ds_deadlist_obj); 3068 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 3069 dsl_dataset_phys(origin_head)->ds_deadlist_obj); 3070 3071 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 3072 3073 spa_history_log_internal_ds(clone, "clone swap", tx, 3074 "parent=%s", origin_head->ds_dir->dd_myname); 3075 } 3076 3077 /* 3078 * Given a pool name and a dataset object number in that pool, 3079 * return the name of that dataset. 3080 */ 3081 int 3082 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 3083 { 3084 dsl_pool_t *dp; 3085 dsl_dataset_t *ds; 3086 int error; 3087 3088 error = dsl_pool_hold(pname, FTAG, &dp); 3089 if (error != 0) 3090 return (error); 3091 3092 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 3093 if (error == 0) { 3094 dsl_dataset_name(ds, buf); 3095 dsl_dataset_rele(ds, FTAG); 3096 } 3097 dsl_pool_rele(dp, FTAG); 3098 3099 return (error); 3100 } 3101 3102 int 3103 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 3104 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 3105 { 3106 int error = 0; 3107 3108 ASSERT3S(asize, >, 0); 3109 3110 /* 3111 * *ref_rsrv is the portion of asize that will come from any 3112 * unconsumed refreservation space. 3113 */ 3114 *ref_rsrv = 0; 3115 3116 mutex_enter(&ds->ds_lock); 3117 /* 3118 * Make a space adjustment for reserved bytes. 3119 */ 3120 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) { 3121 ASSERT3U(*used, >=, 3122 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3123 *used -= 3124 (ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3125 *ref_rsrv = 3126 asize - MIN(asize, parent_delta(ds, asize + inflight)); 3127 } 3128 3129 if (!check_quota || ds->ds_quota == 0) { 3130 mutex_exit(&ds->ds_lock); 3131 return (0); 3132 } 3133 /* 3134 * If they are requesting more space, and our current estimate 3135 * is over quota, they get to try again unless the actual 3136 * on-disk is over quota and there are no pending changes (which 3137 * may free up space for us). 3138 */ 3139 if (dsl_dataset_phys(ds)->ds_referenced_bytes + inflight >= 3140 ds->ds_quota) { 3141 if (inflight > 0 || 3142 dsl_dataset_phys(ds)->ds_referenced_bytes < ds->ds_quota) 3143 error = SET_ERROR(ERESTART); 3144 else 3145 error = SET_ERROR(EDQUOT); 3146 } 3147 mutex_exit(&ds->ds_lock); 3148 3149 return (error); 3150 } 3151 3152 typedef struct dsl_dataset_set_qr_arg { 3153 const char *ddsqra_name; 3154 zprop_source_t ddsqra_source; 3155 uint64_t ddsqra_value; 3156 } dsl_dataset_set_qr_arg_t; 3157 3158 3159 /* ARGSUSED */ 3160 static int 3161 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 3162 { 3163 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3164 dsl_pool_t *dp = dmu_tx_pool(tx); 3165 dsl_dataset_t *ds; 3166 int error; 3167 uint64_t newval; 3168 3169 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 3170 return (SET_ERROR(ENOTSUP)); 3171 3172 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3173 if (error != 0) 3174 return (error); 3175 3176 if (ds->ds_is_snapshot) { 3177 dsl_dataset_rele(ds, FTAG); 3178 return (SET_ERROR(EINVAL)); 3179 } 3180 3181 error = dsl_prop_predict(ds->ds_dir, 3182 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3183 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3184 if (error != 0) { 3185 dsl_dataset_rele(ds, FTAG); 3186 return (error); 3187 } 3188 3189 if (newval == 0) { 3190 dsl_dataset_rele(ds, FTAG); 3191 return (0); 3192 } 3193 3194 if (newval < dsl_dataset_phys(ds)->ds_referenced_bytes || 3195 newval < ds->ds_reserved) { 3196 dsl_dataset_rele(ds, FTAG); 3197 return (SET_ERROR(ENOSPC)); 3198 } 3199 3200 dsl_dataset_rele(ds, FTAG); 3201 return (0); 3202 } 3203 3204 static void 3205 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 3206 { 3207 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3208 dsl_pool_t *dp = dmu_tx_pool(tx); 3209 dsl_dataset_t *ds; 3210 uint64_t newval; 3211 3212 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3213 3214 dsl_prop_set_sync_impl(ds, 3215 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3216 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 3217 &ddsqra->ddsqra_value, tx); 3218 3219 VERIFY0(dsl_prop_get_int_ds(ds, 3220 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 3221 3222 if (ds->ds_quota != newval) { 3223 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3224 ds->ds_quota = newval; 3225 } 3226 dsl_dataset_rele(ds, FTAG); 3227 } 3228 3229 int 3230 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 3231 uint64_t refquota) 3232 { 3233 dsl_dataset_set_qr_arg_t ddsqra; 3234 3235 ddsqra.ddsqra_name = dsname; 3236 ddsqra.ddsqra_source = source; 3237 ddsqra.ddsqra_value = refquota; 3238 3239 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 3240 dsl_dataset_set_refquota_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE)); 3241 } 3242 3243 static int 3244 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 3245 { 3246 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3247 dsl_pool_t *dp = dmu_tx_pool(tx); 3248 dsl_dataset_t *ds; 3249 int error; 3250 uint64_t newval, unique; 3251 3252 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 3253 return (SET_ERROR(ENOTSUP)); 3254 3255 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3256 if (error != 0) 3257 return (error); 3258 3259 if (ds->ds_is_snapshot) { 3260 dsl_dataset_rele(ds, FTAG); 3261 return (SET_ERROR(EINVAL)); 3262 } 3263 3264 error = dsl_prop_predict(ds->ds_dir, 3265 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3266 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3267 if (error != 0) { 3268 dsl_dataset_rele(ds, FTAG); 3269 return (error); 3270 } 3271 3272 /* 3273 * If we are doing the preliminary check in open context, the 3274 * space estimates may be inaccurate. 3275 */ 3276 if (!dmu_tx_is_syncing(tx)) { 3277 dsl_dataset_rele(ds, FTAG); 3278 return (0); 3279 } 3280 3281 mutex_enter(&ds->ds_lock); 3282 if (!DS_UNIQUE_IS_ACCURATE(ds)) 3283 dsl_dataset_recalc_head_uniq(ds); 3284 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3285 mutex_exit(&ds->ds_lock); 3286 3287 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 3288 uint64_t delta = MAX(unique, newval) - 3289 MAX(unique, ds->ds_reserved); 3290 3291 if (delta > 3292 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 3293 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 3294 dsl_dataset_rele(ds, FTAG); 3295 return (SET_ERROR(ENOSPC)); 3296 } 3297 } 3298 3299 dsl_dataset_rele(ds, FTAG); 3300 return (0); 3301 } 3302 3303 void 3304 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 3305 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 3306 { 3307 uint64_t newval; 3308 uint64_t unique; 3309 int64_t delta; 3310 3311 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3312 source, sizeof (value), 1, &value, tx); 3313 3314 VERIFY0(dsl_prop_get_int_ds(ds, 3315 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 3316 3317 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3318 mutex_enter(&ds->ds_dir->dd_lock); 3319 mutex_enter(&ds->ds_lock); 3320 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 3321 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3322 delta = MAX(0, (int64_t)(newval - unique)) - 3323 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3324 ds->ds_reserved = newval; 3325 mutex_exit(&ds->ds_lock); 3326 3327 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3328 mutex_exit(&ds->ds_dir->dd_lock); 3329 } 3330 3331 static void 3332 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 3333 { 3334 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3335 dsl_pool_t *dp = dmu_tx_pool(tx); 3336 dsl_dataset_t *ds; 3337 3338 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3339 dsl_dataset_set_refreservation_sync_impl(ds, 3340 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 3341 dsl_dataset_rele(ds, FTAG); 3342 } 3343 3344 int 3345 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 3346 uint64_t refreservation) 3347 { 3348 dsl_dataset_set_qr_arg_t ddsqra; 3349 3350 ddsqra.ddsqra_name = dsname; 3351 ddsqra.ddsqra_source = source; 3352 ddsqra.ddsqra_value = refreservation; 3353 3354 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 3355 dsl_dataset_set_refreservation_sync, &ddsqra, 3356 0, ZFS_SPACE_CHECK_NONE)); 3357 } 3358 3359 /* 3360 * Return (in *usedp) the amount of space written in new that is not 3361 * present in oldsnap. New may be a snapshot or the head. Old must be 3362 * a snapshot before new, in new's filesystem (or its origin). If not then 3363 * fail and return EINVAL. 3364 * 3365 * The written space is calculated by considering two components: First, we 3366 * ignore any freed space, and calculate the written as new's used space 3367 * minus old's used space. Next, we add in the amount of space that was freed 3368 * between the two snapshots, thus reducing new's used space relative to old's. 3369 * Specifically, this is the space that was born before old->ds_creation_txg, 3370 * and freed before new (ie. on new's deadlist or a previous deadlist). 3371 * 3372 * space freed [---------------------] 3373 * snapshots ---O-------O--------O-------O------ 3374 * oldsnap new 3375 */ 3376 int 3377 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 3378 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3379 { 3380 int err = 0; 3381 uint64_t snapobj; 3382 dsl_pool_t *dp = new->ds_dir->dd_pool; 3383 3384 ASSERT(dsl_pool_config_held(dp)); 3385 3386 *usedp = 0; 3387 *usedp += dsl_dataset_phys(new)->ds_referenced_bytes; 3388 *usedp -= dsl_dataset_phys(oldsnap)->ds_referenced_bytes; 3389 3390 *compp = 0; 3391 *compp += dsl_dataset_phys(new)->ds_compressed_bytes; 3392 *compp -= dsl_dataset_phys(oldsnap)->ds_compressed_bytes; 3393 3394 *uncompp = 0; 3395 *uncompp += dsl_dataset_phys(new)->ds_uncompressed_bytes; 3396 *uncompp -= dsl_dataset_phys(oldsnap)->ds_uncompressed_bytes; 3397 3398 snapobj = new->ds_object; 3399 while (snapobj != oldsnap->ds_object) { 3400 dsl_dataset_t *snap; 3401 uint64_t used, comp, uncomp; 3402 3403 if (snapobj == new->ds_object) { 3404 snap = new; 3405 } else { 3406 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 3407 if (err != 0) 3408 break; 3409 } 3410 3411 if (dsl_dataset_phys(snap)->ds_prev_snap_txg == 3412 dsl_dataset_phys(oldsnap)->ds_creation_txg) { 3413 /* 3414 * The blocks in the deadlist can not be born after 3415 * ds_prev_snap_txg, so get the whole deadlist space, 3416 * which is more efficient (especially for old-format 3417 * deadlists). Unfortunately the deadlist code 3418 * doesn't have enough information to make this 3419 * optimization itself. 3420 */ 3421 dsl_deadlist_space(&snap->ds_deadlist, 3422 &used, &comp, &uncomp); 3423 } else { 3424 dsl_deadlist_space_range(&snap->ds_deadlist, 3425 0, dsl_dataset_phys(oldsnap)->ds_creation_txg, 3426 &used, &comp, &uncomp); 3427 } 3428 *usedp += used; 3429 *compp += comp; 3430 *uncompp += uncomp; 3431 3432 /* 3433 * If we get to the beginning of the chain of snapshots 3434 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 3435 * was not a snapshot of/before new. 3436 */ 3437 snapobj = dsl_dataset_phys(snap)->ds_prev_snap_obj; 3438 if (snap != new) 3439 dsl_dataset_rele(snap, FTAG); 3440 if (snapobj == 0) { 3441 err = SET_ERROR(EINVAL); 3442 break; 3443 } 3444 3445 } 3446 return (err); 3447 } 3448 3449 /* 3450 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 3451 * lastsnap, and all snapshots in between are deleted. 3452 * 3453 * blocks that would be freed [---------------------------] 3454 * snapshots ---O-------O--------O-------O--------O 3455 * firstsnap lastsnap 3456 * 3457 * This is the set of blocks that were born after the snap before firstsnap, 3458 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 3459 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 3460 * We calculate this by iterating over the relevant deadlists (from the snap 3461 * after lastsnap, backward to the snap after firstsnap), summing up the 3462 * space on the deadlist that was born after the snap before firstsnap. 3463 */ 3464 int 3465 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 3466 dsl_dataset_t *lastsnap, 3467 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3468 { 3469 int err = 0; 3470 uint64_t snapobj; 3471 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 3472 3473 ASSERT(firstsnap->ds_is_snapshot); 3474 ASSERT(lastsnap->ds_is_snapshot); 3475 3476 /* 3477 * Check that the snapshots are in the same dsl_dir, and firstsnap 3478 * is before lastsnap. 3479 */ 3480 if (firstsnap->ds_dir != lastsnap->ds_dir || 3481 dsl_dataset_phys(firstsnap)->ds_creation_txg > 3482 dsl_dataset_phys(lastsnap)->ds_creation_txg) 3483 return (SET_ERROR(EINVAL)); 3484 3485 *usedp = *compp = *uncompp = 0; 3486 3487 snapobj = dsl_dataset_phys(lastsnap)->ds_next_snap_obj; 3488 while (snapobj != firstsnap->ds_object) { 3489 dsl_dataset_t *ds; 3490 uint64_t used, comp, uncomp; 3491 3492 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 3493 if (err != 0) 3494 break; 3495 3496 dsl_deadlist_space_range(&ds->ds_deadlist, 3497 dsl_dataset_phys(firstsnap)->ds_prev_snap_txg, UINT64_MAX, 3498 &used, &comp, &uncomp); 3499 *usedp += used; 3500 *compp += comp; 3501 *uncompp += uncomp; 3502 3503 snapobj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 3504 ASSERT3U(snapobj, !=, 0); 3505 dsl_dataset_rele(ds, FTAG); 3506 } 3507 return (err); 3508 } 3509 3510 /* 3511 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 3512 * For example, they could both be snapshots of the same filesystem, and 3513 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 3514 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 3515 * filesystem. Or 'earlier' could be the origin's origin. 3516 * 3517 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg. 3518 */ 3519 boolean_t 3520 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier, 3521 uint64_t earlier_txg) 3522 { 3523 dsl_pool_t *dp = later->ds_dir->dd_pool; 3524 int error; 3525 boolean_t ret; 3526 3527 ASSERT(dsl_pool_config_held(dp)); 3528 ASSERT(earlier->ds_is_snapshot || earlier_txg != 0); 3529 3530 if (earlier_txg == 0) 3531 earlier_txg = dsl_dataset_phys(earlier)->ds_creation_txg; 3532 3533 if (later->ds_is_snapshot && 3534 earlier_txg >= dsl_dataset_phys(later)->ds_creation_txg) 3535 return (B_FALSE); 3536 3537 if (later->ds_dir == earlier->ds_dir) 3538 return (B_TRUE); 3539 if (!dsl_dir_is_clone(later->ds_dir)) 3540 return (B_FALSE); 3541 3542 if (dsl_dir_phys(later->ds_dir)->dd_origin_obj == earlier->ds_object) 3543 return (B_TRUE); 3544 dsl_dataset_t *origin; 3545 error = dsl_dataset_hold_obj(dp, 3546 dsl_dir_phys(later->ds_dir)->dd_origin_obj, FTAG, &origin); 3547 if (error != 0) 3548 return (B_FALSE); 3549 ret = dsl_dataset_is_before(origin, earlier, earlier_txg); 3550 dsl_dataset_rele(origin, FTAG); 3551 return (ret); 3552 } 3553 3554 void 3555 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx) 3556 { 3557 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 3558 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx); 3559 } 3560 3561 boolean_t 3562 dsl_dataset_is_zapified(dsl_dataset_t *ds) 3563 { 3564 dmu_object_info_t doi; 3565 3566 dmu_object_info_from_db(ds->ds_dbuf, &doi); 3567 return (doi.doi_type == DMU_OTN_ZAP_METADATA); 3568 } 3569 3570 boolean_t 3571 dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds) 3572 { 3573 return (dsl_dataset_is_zapified(ds) && 3574 zap_contains(ds->ds_dir->dd_pool->dp_meta_objset, 3575 ds->ds_object, DS_FIELD_RESUME_TOGUID) == 0); 3576 } 3577