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 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2011, 2016 by Delphix. All rights reserved. 25 * Copyright (c) 2014, Joyent, Inc. All rights reserved. 26 * Copyright (c) 2014 RackTop Systems. 27 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 28 * Copyright (c) 2014 Integros [integros.com] 29 * Copyright 2016, OmniTI Computer Consulting, Inc. All rights reserved. 30 * Copyright 2017 Nexenta Systems, Inc. 31 */ 32 33 #include <sys/dmu_objset.h> 34 #include <sys/dsl_dataset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_prop.h> 37 #include <sys/dsl_synctask.h> 38 #include <sys/dmu_traverse.h> 39 #include <sys/dmu_impl.h> 40 #include <sys/dmu_tx.h> 41 #include <sys/arc.h> 42 #include <sys/zio.h> 43 #include <sys/zap.h> 44 #include <sys/zfeature.h> 45 #include <sys/unique.h> 46 #include <sys/zfs_context.h> 47 #include <sys/zfs_ioctl.h> 48 #include <sys/spa.h> 49 #include <sys/zfs_znode.h> 50 #include <sys/zfs_onexit.h> 51 #include <sys/zvol.h> 52 #include <sys/dsl_scan.h> 53 #include <sys/dsl_deadlist.h> 54 #include <sys/dsl_destroy.h> 55 #include <sys/dsl_userhold.h> 56 #include <sys/dsl_bookmark.h> 57 #include <sys/dmu_send.h> 58 #include <sys/zio_checksum.h> 59 #include <sys/zio_compress.h> 60 #include <zfs_fletcher.h> 61 62 /* 63 * The SPA supports block sizes up to 16MB. However, very large blocks 64 * can have an impact on i/o latency (e.g. tying up a spinning disk for 65 * ~300ms), and also potentially on the memory allocator. Therefore, 66 * we do not allow the recordsize to be set larger than zfs_max_recordsize 67 * (default 1MB). Larger blocks can be created by changing this tunable, 68 * and pools with larger blocks can always be imported and used, regardless 69 * of this setting. 70 */ 71 int zfs_max_recordsize = 1 * 1024 * 1024; 72 73 #define SWITCH64(x, y) \ 74 { \ 75 uint64_t __tmp = (x); \ 76 (x) = (y); \ 77 (y) = __tmp; \ 78 } 79 80 #define DS_REF_MAX (1ULL << 62) 81 82 extern inline dsl_dataset_phys_t *dsl_dataset_phys(dsl_dataset_t *ds); 83 84 extern int spa_asize_inflation; 85 86 static zil_header_t zero_zil; 87 88 /* 89 * Figure out how much of this delta should be propogated to the dsl_dir 90 * layer. If there's a refreservation, that space has already been 91 * partially accounted for in our ancestors. 92 */ 93 static int64_t 94 parent_delta(dsl_dataset_t *ds, int64_t delta) 95 { 96 dsl_dataset_phys_t *ds_phys; 97 uint64_t old_bytes, new_bytes; 98 99 if (ds->ds_reserved == 0) 100 return (delta); 101 102 ds_phys = dsl_dataset_phys(ds); 103 old_bytes = MAX(ds_phys->ds_unique_bytes, ds->ds_reserved); 104 new_bytes = MAX(ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 105 106 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 107 return (new_bytes - old_bytes); 108 } 109 110 void 111 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 112 { 113 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 114 int compressed = BP_GET_PSIZE(bp); 115 int uncompressed = BP_GET_UCSIZE(bp); 116 int64_t delta; 117 118 dprintf_bp(bp, "ds=%p", ds); 119 120 ASSERT(dmu_tx_is_syncing(tx)); 121 /* It could have been compressed away to nothing */ 122 if (BP_IS_HOLE(bp)) 123 return; 124 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 125 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 126 if (ds == NULL) { 127 dsl_pool_mos_diduse_space(tx->tx_pool, 128 used, compressed, uncompressed); 129 return; 130 } 131 132 ASSERT3U(bp->blk_birth, >, dsl_dataset_phys(ds)->ds_prev_snap_txg); 133 dmu_buf_will_dirty(ds->ds_dbuf, tx); 134 mutex_enter(&ds->ds_lock); 135 delta = parent_delta(ds, used); 136 dsl_dataset_phys(ds)->ds_referenced_bytes += used; 137 dsl_dataset_phys(ds)->ds_compressed_bytes += compressed; 138 dsl_dataset_phys(ds)->ds_uncompressed_bytes += uncompressed; 139 dsl_dataset_phys(ds)->ds_unique_bytes += used; 140 141 if (BP_GET_LSIZE(bp) > SPA_OLD_MAXBLOCKSIZE) { 142 ds->ds_feature_activation_needed[SPA_FEATURE_LARGE_BLOCKS] = 143 B_TRUE; 144 } 145 146 spa_feature_t f = zio_checksum_to_feature(BP_GET_CHECKSUM(bp)); 147 if (f != SPA_FEATURE_NONE) 148 ds->ds_feature_activation_needed[f] = B_TRUE; 149 150 mutex_exit(&ds->ds_lock); 151 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 152 compressed, uncompressed, tx); 153 dsl_dir_transfer_space(ds->ds_dir, used - delta, 154 DD_USED_REFRSRV, DD_USED_HEAD, tx); 155 } 156 157 int 158 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 159 boolean_t async) 160 { 161 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 162 int compressed = BP_GET_PSIZE(bp); 163 int uncompressed = BP_GET_UCSIZE(bp); 164 165 if (BP_IS_HOLE(bp)) 166 return (0); 167 168 ASSERT(dmu_tx_is_syncing(tx)); 169 ASSERT(bp->blk_birth <= tx->tx_txg); 170 171 if (ds == NULL) { 172 dsl_free(tx->tx_pool, tx->tx_txg, bp); 173 dsl_pool_mos_diduse_space(tx->tx_pool, 174 -used, -compressed, -uncompressed); 175 return (used); 176 } 177 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 178 179 ASSERT(!ds->ds_is_snapshot); 180 dmu_buf_will_dirty(ds->ds_dbuf, tx); 181 182 if (bp->blk_birth > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 183 int64_t delta; 184 185 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 186 dsl_free(tx->tx_pool, tx->tx_txg, bp); 187 188 mutex_enter(&ds->ds_lock); 189 ASSERT(dsl_dataset_phys(ds)->ds_unique_bytes >= used || 190 !DS_UNIQUE_IS_ACCURATE(ds)); 191 delta = parent_delta(ds, -used); 192 dsl_dataset_phys(ds)->ds_unique_bytes -= used; 193 mutex_exit(&ds->ds_lock); 194 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 195 delta, -compressed, -uncompressed, tx); 196 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 197 DD_USED_REFRSRV, DD_USED_HEAD, tx); 198 } else { 199 dprintf_bp(bp, "putting on dead list: %s", ""); 200 if (async) { 201 /* 202 * We are here as part of zio's write done callback, 203 * which means we're a zio interrupt thread. We can't 204 * call dsl_deadlist_insert() now because it may block 205 * waiting for I/O. Instead, put bp on the deferred 206 * queue and let dsl_pool_sync() finish the job. 207 */ 208 bplist_append(&ds->ds_pending_deadlist, bp); 209 } else { 210 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 211 } 212 ASSERT3U(ds->ds_prev->ds_object, ==, 213 dsl_dataset_phys(ds)->ds_prev_snap_obj); 214 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_num_children > 0); 215 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 216 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 217 ds->ds_object && bp->blk_birth > 218 dsl_dataset_phys(ds->ds_prev)->ds_prev_snap_txg) { 219 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 220 mutex_enter(&ds->ds_prev->ds_lock); 221 dsl_dataset_phys(ds->ds_prev)->ds_unique_bytes += used; 222 mutex_exit(&ds->ds_prev->ds_lock); 223 } 224 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 225 dsl_dir_transfer_space(ds->ds_dir, used, 226 DD_USED_HEAD, DD_USED_SNAP, tx); 227 } 228 } 229 mutex_enter(&ds->ds_lock); 230 ASSERT3U(dsl_dataset_phys(ds)->ds_referenced_bytes, >=, used); 231 dsl_dataset_phys(ds)->ds_referenced_bytes -= used; 232 ASSERT3U(dsl_dataset_phys(ds)->ds_compressed_bytes, >=, compressed); 233 dsl_dataset_phys(ds)->ds_compressed_bytes -= compressed; 234 ASSERT3U(dsl_dataset_phys(ds)->ds_uncompressed_bytes, >=, uncompressed); 235 dsl_dataset_phys(ds)->ds_uncompressed_bytes -= uncompressed; 236 mutex_exit(&ds->ds_lock); 237 238 return (used); 239 } 240 241 /* 242 * We have to release the fsid syncronously or we risk that a subsequent 243 * mount of the same dataset will fail to unique_insert the fsid. This 244 * failure would manifest itself as the fsid of this dataset changing 245 * between mounts which makes NFS clients quite unhappy. 246 */ 247 static void 248 dsl_dataset_evict_sync(void *dbu) 249 { 250 dsl_dataset_t *ds = dbu; 251 252 ASSERT(ds->ds_owner == NULL); 253 254 unique_remove(ds->ds_fsid_guid); 255 } 256 257 static void 258 dsl_dataset_evict_async(void *dbu) 259 { 260 dsl_dataset_t *ds = dbu; 261 262 ASSERT(ds->ds_owner == NULL); 263 264 ds->ds_dbuf = NULL; 265 266 if (ds->ds_objset != NULL) 267 dmu_objset_evict(ds->ds_objset); 268 269 if (ds->ds_prev) { 270 dsl_dataset_rele(ds->ds_prev, ds); 271 ds->ds_prev = NULL; 272 } 273 274 bplist_destroy(&ds->ds_pending_deadlist); 275 if (ds->ds_deadlist.dl_os != NULL) 276 dsl_deadlist_close(&ds->ds_deadlist); 277 if (ds->ds_dir) 278 dsl_dir_async_rele(ds->ds_dir, ds); 279 280 ASSERT(!list_link_active(&ds->ds_synced_link)); 281 282 list_destroy(&ds->ds_prop_cbs); 283 mutex_destroy(&ds->ds_lock); 284 mutex_destroy(&ds->ds_opening_lock); 285 mutex_destroy(&ds->ds_sendstream_lock); 286 refcount_destroy(&ds->ds_longholds); 287 rrw_destroy(&ds->ds_bp_rwlock); 288 289 kmem_free(ds, sizeof (dsl_dataset_t)); 290 } 291 292 int 293 dsl_dataset_get_snapname(dsl_dataset_t *ds) 294 { 295 dsl_dataset_phys_t *headphys; 296 int err; 297 dmu_buf_t *headdbuf; 298 dsl_pool_t *dp = ds->ds_dir->dd_pool; 299 objset_t *mos = dp->dp_meta_objset; 300 301 if (ds->ds_snapname[0]) 302 return (0); 303 if (dsl_dataset_phys(ds)->ds_next_snap_obj == 0) 304 return (0); 305 306 err = dmu_bonus_hold(mos, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, 307 FTAG, &headdbuf); 308 if (err != 0) 309 return (err); 310 headphys = headdbuf->db_data; 311 err = zap_value_search(dp->dp_meta_objset, 312 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 313 dmu_buf_rele(headdbuf, FTAG); 314 return (err); 315 } 316 317 int 318 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 319 { 320 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 321 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 322 matchtype_t mt = 0; 323 int err; 324 325 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 326 mt = MT_NORMALIZE; 327 328 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 329 value, mt, NULL, 0, NULL); 330 if (err == ENOTSUP && (mt & MT_NORMALIZE)) 331 err = zap_lookup(mos, snapobj, name, 8, 1, value); 332 return (err); 333 } 334 335 int 336 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx, 337 boolean_t adj_cnt) 338 { 339 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 340 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 341 matchtype_t mt = 0; 342 int err; 343 344 dsl_dir_snap_cmtime_update(ds->ds_dir); 345 346 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 347 mt = MT_NORMALIZE; 348 349 err = zap_remove_norm(mos, snapobj, name, mt, tx); 350 if (err == ENOTSUP && (mt & MT_NORMALIZE)) 351 err = zap_remove(mos, snapobj, name, tx); 352 353 if (err == 0 && adj_cnt) 354 dsl_fs_ss_count_adjust(ds->ds_dir, -1, 355 DD_FIELD_SNAPSHOT_COUNT, tx); 356 357 return (err); 358 } 359 360 boolean_t 361 dsl_dataset_try_add_ref(dsl_pool_t *dp, dsl_dataset_t *ds, void *tag) 362 { 363 dmu_buf_t *dbuf = ds->ds_dbuf; 364 boolean_t result = B_FALSE; 365 366 if (dbuf != NULL && dmu_buf_try_add_ref(dbuf, dp->dp_meta_objset, 367 ds->ds_object, DMU_BONUS_BLKID, tag)) { 368 369 if (ds == dmu_buf_get_user(dbuf)) 370 result = B_TRUE; 371 else 372 dmu_buf_rele(dbuf, tag); 373 } 374 375 return (result); 376 } 377 378 int 379 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 380 dsl_dataset_t **dsp) 381 { 382 objset_t *mos = dp->dp_meta_objset; 383 dmu_buf_t *dbuf; 384 dsl_dataset_t *ds; 385 int err; 386 dmu_object_info_t doi; 387 388 ASSERT(dsl_pool_config_held(dp)); 389 390 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 391 if (err != 0) 392 return (err); 393 394 /* Make sure dsobj has the correct object type. */ 395 dmu_object_info_from_db(dbuf, &doi); 396 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) { 397 dmu_buf_rele(dbuf, tag); 398 return (SET_ERROR(EINVAL)); 399 } 400 401 ds = dmu_buf_get_user(dbuf); 402 if (ds == NULL) { 403 dsl_dataset_t *winner = NULL; 404 405 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 406 ds->ds_dbuf = dbuf; 407 ds->ds_object = dsobj; 408 ds->ds_is_snapshot = dsl_dataset_phys(ds)->ds_num_children != 0; 409 410 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 411 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 412 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 413 rrw_init(&ds->ds_bp_rwlock, B_FALSE); 414 refcount_create(&ds->ds_longholds); 415 416 bplist_create(&ds->ds_pending_deadlist); 417 dsl_deadlist_open(&ds->ds_deadlist, 418 mos, dsl_dataset_phys(ds)->ds_deadlist_obj); 419 420 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 421 offsetof(dmu_sendarg_t, dsa_link)); 422 423 list_create(&ds->ds_prop_cbs, sizeof (dsl_prop_cb_record_t), 424 offsetof(dsl_prop_cb_record_t, cbr_ds_node)); 425 426 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 427 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 428 if (!(spa_feature_table[f].fi_flags & 429 ZFEATURE_FLAG_PER_DATASET)) 430 continue; 431 err = zap_contains(mos, dsobj, 432 spa_feature_table[f].fi_guid); 433 if (err == 0) { 434 ds->ds_feature_inuse[f] = B_TRUE; 435 } else { 436 ASSERT3U(err, ==, ENOENT); 437 err = 0; 438 } 439 } 440 } 441 442 err = dsl_dir_hold_obj(dp, 443 dsl_dataset_phys(ds)->ds_dir_obj, NULL, ds, &ds->ds_dir); 444 if (err != 0) { 445 mutex_destroy(&ds->ds_lock); 446 mutex_destroy(&ds->ds_opening_lock); 447 mutex_destroy(&ds->ds_sendstream_lock); 448 refcount_destroy(&ds->ds_longholds); 449 bplist_destroy(&ds->ds_pending_deadlist); 450 dsl_deadlist_close(&ds->ds_deadlist); 451 kmem_free(ds, sizeof (dsl_dataset_t)); 452 dmu_buf_rele(dbuf, tag); 453 return (err); 454 } 455 456 if (!ds->ds_is_snapshot) { 457 ds->ds_snapname[0] = '\0'; 458 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 459 err = dsl_dataset_hold_obj(dp, 460 dsl_dataset_phys(ds)->ds_prev_snap_obj, 461 ds, &ds->ds_prev); 462 } 463 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 464 int zaperr = zap_lookup(mos, ds->ds_object, 465 DS_FIELD_BOOKMARK_NAMES, 466 sizeof (ds->ds_bookmarks), 1, 467 &ds->ds_bookmarks); 468 if (zaperr != ENOENT) 469 VERIFY0(zaperr); 470 } 471 } else { 472 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 473 err = dsl_dataset_get_snapname(ds); 474 if (err == 0 && 475 dsl_dataset_phys(ds)->ds_userrefs_obj != 0) { 476 err = zap_count( 477 ds->ds_dir->dd_pool->dp_meta_objset, 478 dsl_dataset_phys(ds)->ds_userrefs_obj, 479 &ds->ds_userrefs); 480 } 481 } 482 483 if (err == 0 && !ds->ds_is_snapshot) { 484 err = dsl_prop_get_int_ds(ds, 485 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 486 &ds->ds_reserved); 487 if (err == 0) { 488 err = dsl_prop_get_int_ds(ds, 489 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 490 &ds->ds_quota); 491 } 492 } else { 493 ds->ds_reserved = ds->ds_quota = 0; 494 } 495 496 dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict_sync, 497 dsl_dataset_evict_async, &ds->ds_dbuf); 498 if (err == 0) 499 winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu); 500 501 if (err != 0 || winner != NULL) { 502 bplist_destroy(&ds->ds_pending_deadlist); 503 dsl_deadlist_close(&ds->ds_deadlist); 504 if (ds->ds_prev) 505 dsl_dataset_rele(ds->ds_prev, ds); 506 dsl_dir_rele(ds->ds_dir, ds); 507 mutex_destroy(&ds->ds_lock); 508 mutex_destroy(&ds->ds_opening_lock); 509 mutex_destroy(&ds->ds_sendstream_lock); 510 refcount_destroy(&ds->ds_longholds); 511 kmem_free(ds, sizeof (dsl_dataset_t)); 512 if (err != 0) { 513 dmu_buf_rele(dbuf, tag); 514 return (err); 515 } 516 ds = winner; 517 } else { 518 ds->ds_fsid_guid = 519 unique_insert(dsl_dataset_phys(ds)->ds_fsid_guid); 520 if (ds->ds_fsid_guid != 521 dsl_dataset_phys(ds)->ds_fsid_guid) { 522 zfs_dbgmsg("ds_fsid_guid changed from " 523 "%llx to %llx for pool %s dataset id %llu", 524 (long long) 525 dsl_dataset_phys(ds)->ds_fsid_guid, 526 (long long)ds->ds_fsid_guid, 527 spa_name(dp->dp_spa), 528 dsobj); 529 } 530 } 531 } 532 ASSERT3P(ds->ds_dbuf, ==, dbuf); 533 ASSERT3P(dsl_dataset_phys(ds), ==, dbuf->db_data); 534 ASSERT(dsl_dataset_phys(ds)->ds_prev_snap_obj != 0 || 535 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 536 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 537 *dsp = ds; 538 return (0); 539 } 540 541 int 542 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 543 void *tag, dsl_dataset_t **dsp) 544 { 545 dsl_dir_t *dd; 546 const char *snapname; 547 uint64_t obj; 548 int err = 0; 549 dsl_dataset_t *ds; 550 551 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 552 if (err != 0) 553 return (err); 554 555 ASSERT(dsl_pool_config_held(dp)); 556 obj = dsl_dir_phys(dd)->dd_head_dataset_obj; 557 if (obj != 0) 558 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 559 else 560 err = SET_ERROR(ENOENT); 561 562 /* we may be looking for a snapshot */ 563 if (err == 0 && snapname != NULL) { 564 dsl_dataset_t *snap_ds; 565 566 if (*snapname++ != '@') { 567 dsl_dataset_rele(ds, tag); 568 dsl_dir_rele(dd, FTAG); 569 return (SET_ERROR(ENOENT)); 570 } 571 572 dprintf("looking for snapshot '%s'\n", snapname); 573 err = dsl_dataset_snap_lookup(ds, snapname, &obj); 574 if (err == 0) 575 err = dsl_dataset_hold_obj(dp, obj, tag, &snap_ds); 576 dsl_dataset_rele(ds, tag); 577 578 if (err == 0) { 579 mutex_enter(&snap_ds->ds_lock); 580 if (snap_ds->ds_snapname[0] == 0) 581 (void) strlcpy(snap_ds->ds_snapname, snapname, 582 sizeof (snap_ds->ds_snapname)); 583 mutex_exit(&snap_ds->ds_lock); 584 ds = snap_ds; 585 } 586 } 587 if (err == 0) 588 *dsp = ds; 589 dsl_dir_rele(dd, FTAG); 590 return (err); 591 } 592 593 int 594 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 595 void *tag, dsl_dataset_t **dsp) 596 { 597 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 598 if (err != 0) 599 return (err); 600 if (!dsl_dataset_tryown(*dsp, tag)) { 601 dsl_dataset_rele(*dsp, tag); 602 *dsp = NULL; 603 return (SET_ERROR(EBUSY)); 604 } 605 return (0); 606 } 607 608 int 609 dsl_dataset_own(dsl_pool_t *dp, const char *name, 610 void *tag, dsl_dataset_t **dsp) 611 { 612 int err = dsl_dataset_hold(dp, name, tag, dsp); 613 if (err != 0) 614 return (err); 615 if (!dsl_dataset_tryown(*dsp, tag)) { 616 dsl_dataset_rele(*dsp, tag); 617 return (SET_ERROR(EBUSY)); 618 } 619 return (0); 620 } 621 622 /* 623 * See the comment above dsl_pool_hold() for details. In summary, a long 624 * hold is used to prevent destruction of a dataset while the pool hold 625 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 626 * 627 * The dataset and pool must be held when this function is called. After it 628 * is called, the pool hold may be released while the dataset is still held 629 * and accessed. 630 */ 631 void 632 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 633 { 634 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 635 (void) refcount_add(&ds->ds_longholds, tag); 636 } 637 638 void 639 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 640 { 641 (void) refcount_remove(&ds->ds_longholds, tag); 642 } 643 644 /* Return B_TRUE if there are any long holds on this dataset. */ 645 boolean_t 646 dsl_dataset_long_held(dsl_dataset_t *ds) 647 { 648 return (!refcount_is_zero(&ds->ds_longholds)); 649 } 650 651 void 652 dsl_dataset_name(dsl_dataset_t *ds, char *name) 653 { 654 if (ds == NULL) { 655 (void) strcpy(name, "mos"); 656 } else { 657 dsl_dir_name(ds->ds_dir, name); 658 VERIFY0(dsl_dataset_get_snapname(ds)); 659 if (ds->ds_snapname[0]) { 660 VERIFY3U(strlcat(name, "@", ZFS_MAX_DATASET_NAME_LEN), 661 <, ZFS_MAX_DATASET_NAME_LEN); 662 /* 663 * We use a "recursive" mutex so that we 664 * can call dprintf_ds() with ds_lock held. 665 */ 666 if (!MUTEX_HELD(&ds->ds_lock)) { 667 mutex_enter(&ds->ds_lock); 668 VERIFY3U(strlcat(name, ds->ds_snapname, 669 ZFS_MAX_DATASET_NAME_LEN), <, 670 ZFS_MAX_DATASET_NAME_LEN); 671 mutex_exit(&ds->ds_lock); 672 } else { 673 VERIFY3U(strlcat(name, ds->ds_snapname, 674 ZFS_MAX_DATASET_NAME_LEN), <, 675 ZFS_MAX_DATASET_NAME_LEN); 676 } 677 } 678 } 679 } 680 681 int 682 dsl_dataset_namelen(dsl_dataset_t *ds) 683 { 684 VERIFY0(dsl_dataset_get_snapname(ds)); 685 mutex_enter(&ds->ds_lock); 686 int len = dsl_dir_namelen(ds->ds_dir) + 1 + strlen(ds->ds_snapname); 687 mutex_exit(&ds->ds_lock); 688 return (len); 689 } 690 691 void 692 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 693 { 694 dmu_buf_rele(ds->ds_dbuf, tag); 695 } 696 697 void 698 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 699 { 700 ASSERT3P(ds->ds_owner, ==, tag); 701 ASSERT(ds->ds_dbuf != NULL); 702 703 mutex_enter(&ds->ds_lock); 704 ds->ds_owner = NULL; 705 mutex_exit(&ds->ds_lock); 706 dsl_dataset_long_rele(ds, tag); 707 dsl_dataset_rele(ds, tag); 708 } 709 710 boolean_t 711 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 712 { 713 boolean_t gotit = FALSE; 714 715 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 716 mutex_enter(&ds->ds_lock); 717 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 718 ds->ds_owner = tag; 719 dsl_dataset_long_hold(ds, tag); 720 gotit = TRUE; 721 } 722 mutex_exit(&ds->ds_lock); 723 return (gotit); 724 } 725 726 boolean_t 727 dsl_dataset_has_owner(dsl_dataset_t *ds) 728 { 729 boolean_t rv; 730 mutex_enter(&ds->ds_lock); 731 rv = (ds->ds_owner != NULL); 732 mutex_exit(&ds->ds_lock); 733 return (rv); 734 } 735 736 static void 737 dsl_dataset_activate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 738 { 739 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 740 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 741 uint64_t zero = 0; 742 743 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 744 745 spa_feature_incr(spa, f, tx); 746 dmu_object_zapify(mos, dsobj, DMU_OT_DSL_DATASET, tx); 747 748 VERIFY0(zap_add(mos, dsobj, spa_feature_table[f].fi_guid, 749 sizeof (zero), 1, &zero, tx)); 750 } 751 752 void 753 dsl_dataset_deactivate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 754 { 755 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 756 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 757 758 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 759 760 VERIFY0(zap_remove(mos, dsobj, spa_feature_table[f].fi_guid, tx)); 761 spa_feature_decr(spa, f, tx); 762 } 763 764 uint64_t 765 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 766 uint64_t flags, dmu_tx_t *tx) 767 { 768 dsl_pool_t *dp = dd->dd_pool; 769 dmu_buf_t *dbuf; 770 dsl_dataset_phys_t *dsphys; 771 uint64_t dsobj; 772 objset_t *mos = dp->dp_meta_objset; 773 774 if (origin == NULL) 775 origin = dp->dp_origin_snap; 776 777 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 778 ASSERT(origin == NULL || dsl_dataset_phys(origin)->ds_num_children > 0); 779 ASSERT(dmu_tx_is_syncing(tx)); 780 ASSERT(dsl_dir_phys(dd)->dd_head_dataset_obj == 0); 781 782 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 783 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 784 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 785 dmu_buf_will_dirty(dbuf, tx); 786 dsphys = dbuf->db_data; 787 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 788 dsphys->ds_dir_obj = dd->dd_object; 789 dsphys->ds_flags = flags; 790 dsphys->ds_fsid_guid = unique_create(); 791 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 792 sizeof (dsphys->ds_guid)); 793 dsphys->ds_snapnames_zapobj = 794 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 795 DMU_OT_NONE, 0, tx); 796 dsphys->ds_creation_time = gethrestime_sec(); 797 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 798 799 if (origin == NULL) { 800 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 801 } else { 802 dsl_dataset_t *ohds; /* head of the origin snapshot */ 803 804 dsphys->ds_prev_snap_obj = origin->ds_object; 805 dsphys->ds_prev_snap_txg = 806 dsl_dataset_phys(origin)->ds_creation_txg; 807 dsphys->ds_referenced_bytes = 808 dsl_dataset_phys(origin)->ds_referenced_bytes; 809 dsphys->ds_compressed_bytes = 810 dsl_dataset_phys(origin)->ds_compressed_bytes; 811 dsphys->ds_uncompressed_bytes = 812 dsl_dataset_phys(origin)->ds_uncompressed_bytes; 813 rrw_enter(&origin->ds_bp_rwlock, RW_READER, FTAG); 814 dsphys->ds_bp = dsl_dataset_phys(origin)->ds_bp; 815 rrw_exit(&origin->ds_bp_rwlock, FTAG); 816 817 /* 818 * Inherit flags that describe the dataset's contents 819 * (INCONSISTENT) or properties (Case Insensitive). 820 */ 821 dsphys->ds_flags |= dsl_dataset_phys(origin)->ds_flags & 822 (DS_FLAG_INCONSISTENT | DS_FLAG_CI_DATASET); 823 824 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 825 if (origin->ds_feature_inuse[f]) 826 dsl_dataset_activate_feature(dsobj, f, tx); 827 } 828 829 dmu_buf_will_dirty(origin->ds_dbuf, tx); 830 dsl_dataset_phys(origin)->ds_num_children++; 831 832 VERIFY0(dsl_dataset_hold_obj(dp, 833 dsl_dir_phys(origin->ds_dir)->dd_head_dataset_obj, 834 FTAG, &ohds)); 835 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 836 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 837 dsl_dataset_rele(ohds, FTAG); 838 839 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 840 if (dsl_dataset_phys(origin)->ds_next_clones_obj == 0) { 841 dsl_dataset_phys(origin)->ds_next_clones_obj = 842 zap_create(mos, 843 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 844 } 845 VERIFY0(zap_add_int(mos, 846 dsl_dataset_phys(origin)->ds_next_clones_obj, 847 dsobj, tx)); 848 } 849 850 dmu_buf_will_dirty(dd->dd_dbuf, tx); 851 dsl_dir_phys(dd)->dd_origin_obj = origin->ds_object; 852 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 853 if (dsl_dir_phys(origin->ds_dir)->dd_clones == 0) { 854 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 855 dsl_dir_phys(origin->ds_dir)->dd_clones = 856 zap_create(mos, 857 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 858 } 859 VERIFY0(zap_add_int(mos, 860 dsl_dir_phys(origin->ds_dir)->dd_clones, 861 dsobj, tx)); 862 } 863 } 864 865 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 866 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 867 868 dmu_buf_rele(dbuf, FTAG); 869 870 dmu_buf_will_dirty(dd->dd_dbuf, tx); 871 dsl_dir_phys(dd)->dd_head_dataset_obj = dsobj; 872 873 return (dsobj); 874 } 875 876 static void 877 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 878 { 879 objset_t *os; 880 881 VERIFY0(dmu_objset_from_ds(ds, &os)); 882 if (bcmp(&os->os_zil_header, &zero_zil, sizeof (zero_zil)) != 0) { 883 dsl_pool_t *dp = ds->ds_dir->dd_pool; 884 zio_t *zio; 885 886 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 887 888 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 889 dsl_dataset_sync(ds, zio, tx); 890 VERIFY0(zio_wait(zio)); 891 892 /* dsl_dataset_sync_done will drop this reference. */ 893 dmu_buf_add_ref(ds->ds_dbuf, ds); 894 dsl_dataset_sync_done(ds, tx); 895 } 896 } 897 898 uint64_t 899 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 900 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 901 { 902 dsl_pool_t *dp = pdd->dd_pool; 903 uint64_t dsobj, ddobj; 904 dsl_dir_t *dd; 905 906 ASSERT(dmu_tx_is_syncing(tx)); 907 ASSERT(lastname[0] != '@'); 908 909 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 910 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 911 912 dsobj = dsl_dataset_create_sync_dd(dd, origin, 913 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 914 915 dsl_deleg_set_create_perms(dd, tx, cr); 916 917 /* 918 * Since we're creating a new node we know it's a leaf, so we can 919 * initialize the counts if the limit feature is active. 920 */ 921 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) { 922 uint64_t cnt = 0; 923 objset_t *os = dd->dd_pool->dp_meta_objset; 924 925 dsl_dir_zapify(dd, tx); 926 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT, 927 sizeof (cnt), 1, &cnt, tx)); 928 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT, 929 sizeof (cnt), 1, &cnt, tx)); 930 } 931 932 dsl_dir_rele(dd, FTAG); 933 934 /* 935 * If we are creating a clone, make sure we zero out any stale 936 * data from the origin snapshots zil header. 937 */ 938 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 939 dsl_dataset_t *ds; 940 941 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 942 dsl_dataset_zero_zil(ds, tx); 943 dsl_dataset_rele(ds, FTAG); 944 } 945 946 return (dsobj); 947 } 948 949 /* 950 * The unique space in the head dataset can be calculated by subtracting 951 * the space used in the most recent snapshot, that is still being used 952 * in this file system, from the space currently in use. To figure out 953 * the space in the most recent snapshot still in use, we need to take 954 * the total space used in the snapshot and subtract out the space that 955 * has been freed up since the snapshot was taken. 956 */ 957 void 958 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 959 { 960 uint64_t mrs_used; 961 uint64_t dlused, dlcomp, dluncomp; 962 963 ASSERT(!ds->ds_is_snapshot); 964 965 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) 966 mrs_used = dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes; 967 else 968 mrs_used = 0; 969 970 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 971 972 ASSERT3U(dlused, <=, mrs_used); 973 dsl_dataset_phys(ds)->ds_unique_bytes = 974 dsl_dataset_phys(ds)->ds_referenced_bytes - (mrs_used - dlused); 975 976 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 977 SPA_VERSION_UNIQUE_ACCURATE) 978 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 979 } 980 981 void 982 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 983 dmu_tx_t *tx) 984 { 985 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 986 uint64_t count; 987 int err; 988 989 ASSERT(dsl_dataset_phys(ds)->ds_num_children >= 2); 990 err = zap_remove_int(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 991 obj, tx); 992 /* 993 * The err should not be ENOENT, but a bug in a previous version 994 * of the code could cause upgrade_clones_cb() to not set 995 * ds_next_snap_obj when it should, leading to a missing entry. 996 * If we knew that the pool was created after 997 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 998 * ENOENT. However, at least we can check that we don't have 999 * too many entries in the next_clones_obj even after failing to 1000 * remove this one. 1001 */ 1002 if (err != ENOENT) 1003 VERIFY0(err); 1004 ASSERT0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1005 &count)); 1006 ASSERT3U(count, <=, dsl_dataset_phys(ds)->ds_num_children - 2); 1007 } 1008 1009 1010 blkptr_t * 1011 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1012 { 1013 return (&dsl_dataset_phys(ds)->ds_bp); 1014 } 1015 1016 spa_t * 1017 dsl_dataset_get_spa(dsl_dataset_t *ds) 1018 { 1019 return (ds->ds_dir->dd_pool->dp_spa); 1020 } 1021 1022 void 1023 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1024 { 1025 dsl_pool_t *dp; 1026 1027 if (ds == NULL) /* this is the meta-objset */ 1028 return; 1029 1030 ASSERT(ds->ds_objset != NULL); 1031 1032 if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) 1033 panic("dirtying snapshot!"); 1034 1035 /* Must not dirty a dataset in the same txg where it got snapshotted. */ 1036 ASSERT3U(tx->tx_txg, >, dsl_dataset_phys(ds)->ds_prev_snap_txg); 1037 1038 dp = ds->ds_dir->dd_pool; 1039 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 1040 /* up the hold count until we can be written out */ 1041 dmu_buf_add_ref(ds->ds_dbuf, ds); 1042 } 1043 } 1044 1045 boolean_t 1046 dsl_dataset_is_dirty(dsl_dataset_t *ds) 1047 { 1048 for (int t = 0; t < TXG_SIZE; t++) { 1049 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 1050 ds, t)) 1051 return (B_TRUE); 1052 } 1053 return (B_FALSE); 1054 } 1055 1056 static int 1057 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1058 { 1059 uint64_t asize; 1060 1061 if (!dmu_tx_is_syncing(tx)) 1062 return (0); 1063 1064 /* 1065 * If there's an fs-only reservation, any blocks that might become 1066 * owned by the snapshot dataset must be accommodated by space 1067 * outside of the reservation. 1068 */ 1069 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 1070 asize = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, ds->ds_reserved); 1071 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 1072 return (SET_ERROR(ENOSPC)); 1073 1074 /* 1075 * Propagate any reserved space for this snapshot to other 1076 * snapshot checks in this sync group. 1077 */ 1078 if (asize > 0) 1079 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1080 1081 return (0); 1082 } 1083 1084 typedef struct dsl_dataset_snapshot_arg { 1085 nvlist_t *ddsa_snaps; 1086 nvlist_t *ddsa_props; 1087 nvlist_t *ddsa_errors; 1088 cred_t *ddsa_cr; 1089 } dsl_dataset_snapshot_arg_t; 1090 1091 int 1092 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 1093 dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr) 1094 { 1095 int error; 1096 uint64_t value; 1097 1098 ds->ds_trysnap_txg = tx->tx_txg; 1099 1100 if (!dmu_tx_is_syncing(tx)) 1101 return (0); 1102 1103 /* 1104 * We don't allow multiple snapshots of the same txg. If there 1105 * is already one, try again. 1106 */ 1107 if (dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg) 1108 return (SET_ERROR(EAGAIN)); 1109 1110 /* 1111 * Check for conflicting snapshot name. 1112 */ 1113 error = dsl_dataset_snap_lookup(ds, snapname, &value); 1114 if (error == 0) 1115 return (SET_ERROR(EEXIST)); 1116 if (error != ENOENT) 1117 return (error); 1118 1119 /* 1120 * We don't allow taking snapshots of inconsistent datasets, such as 1121 * those into which we are currently receiving. However, if we are 1122 * creating this snapshot as part of a receive, this check will be 1123 * executed atomically with respect to the completion of the receive 1124 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 1125 * case we ignore this, knowing it will be fixed up for us shortly in 1126 * dmu_recv_end_sync(). 1127 */ 1128 if (!recv && DS_IS_INCONSISTENT(ds)) 1129 return (SET_ERROR(EBUSY)); 1130 1131 /* 1132 * Skip the check for temporary snapshots or if we have already checked 1133 * the counts in dsl_dataset_snapshot_check. This means we really only 1134 * check the count here when we're receiving a stream. 1135 */ 1136 if (cnt != 0 && cr != NULL) { 1137 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1138 ZFS_PROP_SNAPSHOT_LIMIT, NULL, cr); 1139 if (error != 0) 1140 return (error); 1141 } 1142 1143 error = dsl_dataset_snapshot_reserve_space(ds, tx); 1144 if (error != 0) 1145 return (error); 1146 1147 return (0); 1148 } 1149 1150 static int 1151 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 1152 { 1153 dsl_dataset_snapshot_arg_t *ddsa = arg; 1154 dsl_pool_t *dp = dmu_tx_pool(tx); 1155 nvpair_t *pair; 1156 int rv = 0; 1157 1158 /* 1159 * Pre-compute how many total new snapshots will be created for each 1160 * level in the tree and below. This is needed for validating the 1161 * snapshot limit when either taking a recursive snapshot or when 1162 * taking multiple snapshots. 1163 * 1164 * The problem is that the counts are not actually adjusted when 1165 * we are checking, only when we finally sync. For a single snapshot, 1166 * this is easy, the count will increase by 1 at each node up the tree, 1167 * but its more complicated for the recursive/multiple snapshot case. 1168 * 1169 * The dsl_fs_ss_limit_check function does recursively check the count 1170 * at each level up the tree but since it is validating each snapshot 1171 * independently we need to be sure that we are validating the complete 1172 * count for the entire set of snapshots. We do this by rolling up the 1173 * counts for each component of the name into an nvlist and then 1174 * checking each of those cases with the aggregated count. 1175 * 1176 * This approach properly handles not only the recursive snapshot 1177 * case (where we get all of those on the ddsa_snaps list) but also 1178 * the sibling case (e.g. snapshot a/b and a/c so that we will also 1179 * validate the limit on 'a' using a count of 2). 1180 * 1181 * We validate the snapshot names in the third loop and only report 1182 * name errors once. 1183 */ 1184 if (dmu_tx_is_syncing(tx)) { 1185 nvlist_t *cnt_track = NULL; 1186 cnt_track = fnvlist_alloc(); 1187 1188 /* Rollup aggregated counts into the cnt_track list */ 1189 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1190 pair != NULL; 1191 pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1192 char *pdelim; 1193 uint64_t val; 1194 char nm[MAXPATHLEN]; 1195 1196 (void) strlcpy(nm, nvpair_name(pair), sizeof (nm)); 1197 pdelim = strchr(nm, '@'); 1198 if (pdelim == NULL) 1199 continue; 1200 *pdelim = '\0'; 1201 1202 do { 1203 if (nvlist_lookup_uint64(cnt_track, nm, 1204 &val) == 0) { 1205 /* update existing entry */ 1206 fnvlist_add_uint64(cnt_track, nm, 1207 val + 1); 1208 } else { 1209 /* add to list */ 1210 fnvlist_add_uint64(cnt_track, nm, 1); 1211 } 1212 1213 pdelim = strrchr(nm, '/'); 1214 if (pdelim != NULL) 1215 *pdelim = '\0'; 1216 } while (pdelim != NULL); 1217 } 1218 1219 /* Check aggregated counts at each level */ 1220 for (pair = nvlist_next_nvpair(cnt_track, NULL); 1221 pair != NULL; pair = nvlist_next_nvpair(cnt_track, pair)) { 1222 int error = 0; 1223 char *name; 1224 uint64_t cnt = 0; 1225 dsl_dataset_t *ds; 1226 1227 name = nvpair_name(pair); 1228 cnt = fnvpair_value_uint64(pair); 1229 ASSERT(cnt > 0); 1230 1231 error = dsl_dataset_hold(dp, name, FTAG, &ds); 1232 if (error == 0) { 1233 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1234 ZFS_PROP_SNAPSHOT_LIMIT, NULL, 1235 ddsa->ddsa_cr); 1236 dsl_dataset_rele(ds, FTAG); 1237 } 1238 1239 if (error != 0) { 1240 if (ddsa->ddsa_errors != NULL) 1241 fnvlist_add_int32(ddsa->ddsa_errors, 1242 name, error); 1243 rv = error; 1244 /* only report one error for this check */ 1245 break; 1246 } 1247 } 1248 nvlist_free(cnt_track); 1249 } 1250 1251 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1252 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1253 int error = 0; 1254 dsl_dataset_t *ds; 1255 char *name, *atp; 1256 char dsname[ZFS_MAX_DATASET_NAME_LEN]; 1257 1258 name = nvpair_name(pair); 1259 if (strlen(name) >= ZFS_MAX_DATASET_NAME_LEN) 1260 error = SET_ERROR(ENAMETOOLONG); 1261 if (error == 0) { 1262 atp = strchr(name, '@'); 1263 if (atp == NULL) 1264 error = SET_ERROR(EINVAL); 1265 if (error == 0) 1266 (void) strlcpy(dsname, name, atp - name + 1); 1267 } 1268 if (error == 0) 1269 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1270 if (error == 0) { 1271 /* passing 0/NULL skips dsl_fs_ss_limit_check */ 1272 error = dsl_dataset_snapshot_check_impl(ds, 1273 atp + 1, tx, B_FALSE, 0, NULL); 1274 dsl_dataset_rele(ds, FTAG); 1275 } 1276 1277 if (error != 0) { 1278 if (ddsa->ddsa_errors != NULL) { 1279 fnvlist_add_int32(ddsa->ddsa_errors, 1280 name, error); 1281 } 1282 rv = error; 1283 } 1284 } 1285 1286 return (rv); 1287 } 1288 1289 void 1290 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1291 dmu_tx_t *tx) 1292 { 1293 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1294 dmu_buf_t *dbuf; 1295 dsl_dataset_phys_t *dsphys; 1296 uint64_t dsobj, crtxg; 1297 objset_t *mos = dp->dp_meta_objset; 1298 objset_t *os; 1299 1300 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1301 1302 /* 1303 * If we are on an old pool, the zil must not be active, in which 1304 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1305 */ 1306 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1307 dmu_objset_from_ds(ds, &os) != 0 || 1308 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1309 sizeof (zero_zil)) == 0); 1310 1311 /* Should not snapshot a dirty dataset. */ 1312 ASSERT(!txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 1313 ds, tx->tx_txg)); 1314 1315 dsl_fs_ss_count_adjust(ds->ds_dir, 1, DD_FIELD_SNAPSHOT_COUNT, tx); 1316 1317 /* 1318 * The origin's ds_creation_txg has to be < TXG_INITIAL 1319 */ 1320 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1321 crtxg = 1; 1322 else 1323 crtxg = tx->tx_txg; 1324 1325 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1326 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1327 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1328 dmu_buf_will_dirty(dbuf, tx); 1329 dsphys = dbuf->db_data; 1330 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1331 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1332 dsphys->ds_fsid_guid = unique_create(); 1333 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1334 sizeof (dsphys->ds_guid)); 1335 dsphys->ds_prev_snap_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 1336 dsphys->ds_prev_snap_txg = dsl_dataset_phys(ds)->ds_prev_snap_txg; 1337 dsphys->ds_next_snap_obj = ds->ds_object; 1338 dsphys->ds_num_children = 1; 1339 dsphys->ds_creation_time = gethrestime_sec(); 1340 dsphys->ds_creation_txg = crtxg; 1341 dsphys->ds_deadlist_obj = dsl_dataset_phys(ds)->ds_deadlist_obj; 1342 dsphys->ds_referenced_bytes = dsl_dataset_phys(ds)->ds_referenced_bytes; 1343 dsphys->ds_compressed_bytes = dsl_dataset_phys(ds)->ds_compressed_bytes; 1344 dsphys->ds_uncompressed_bytes = 1345 dsl_dataset_phys(ds)->ds_uncompressed_bytes; 1346 dsphys->ds_flags = dsl_dataset_phys(ds)->ds_flags; 1347 rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); 1348 dsphys->ds_bp = dsl_dataset_phys(ds)->ds_bp; 1349 rrw_exit(&ds->ds_bp_rwlock, FTAG); 1350 dmu_buf_rele(dbuf, FTAG); 1351 1352 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1353 if (ds->ds_feature_inuse[f]) 1354 dsl_dataset_activate_feature(dsobj, f, tx); 1355 } 1356 1357 ASSERT3U(ds->ds_prev != 0, ==, 1358 dsl_dataset_phys(ds)->ds_prev_snap_obj != 0); 1359 if (ds->ds_prev) { 1360 uint64_t next_clones_obj = 1361 dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj; 1362 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1363 ds->ds_object || 1364 dsl_dataset_phys(ds->ds_prev)->ds_num_children > 1); 1365 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1366 ds->ds_object) { 1367 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1368 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==, 1369 dsl_dataset_phys(ds->ds_prev)->ds_creation_txg); 1370 dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj = dsobj; 1371 } else if (next_clones_obj != 0) { 1372 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1373 dsphys->ds_next_snap_obj, tx); 1374 VERIFY0(zap_add_int(mos, 1375 next_clones_obj, dsobj, tx)); 1376 } 1377 } 1378 1379 /* 1380 * If we have a reference-reservation on this dataset, we will 1381 * need to increase the amount of refreservation being charged 1382 * since our unique space is going to zero. 1383 */ 1384 if (ds->ds_reserved) { 1385 int64_t delta; 1386 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1387 delta = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, 1388 ds->ds_reserved); 1389 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1390 delta, 0, 0, tx); 1391 } 1392 1393 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1394 dsl_dataset_phys(ds)->ds_deadlist_obj = 1395 dsl_deadlist_clone(&ds->ds_deadlist, UINT64_MAX, 1396 dsl_dataset_phys(ds)->ds_prev_snap_obj, tx); 1397 dsl_deadlist_close(&ds->ds_deadlist); 1398 dsl_deadlist_open(&ds->ds_deadlist, mos, 1399 dsl_dataset_phys(ds)->ds_deadlist_obj); 1400 dsl_deadlist_add_key(&ds->ds_deadlist, 1401 dsl_dataset_phys(ds)->ds_prev_snap_txg, tx); 1402 1403 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, <, tx->tx_txg); 1404 dsl_dataset_phys(ds)->ds_prev_snap_obj = dsobj; 1405 dsl_dataset_phys(ds)->ds_prev_snap_txg = crtxg; 1406 dsl_dataset_phys(ds)->ds_unique_bytes = 0; 1407 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1408 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1409 1410 VERIFY0(zap_add(mos, dsl_dataset_phys(ds)->ds_snapnames_zapobj, 1411 snapname, 8, 1, &dsobj, tx)); 1412 1413 if (ds->ds_prev) 1414 dsl_dataset_rele(ds->ds_prev, ds); 1415 VERIFY0(dsl_dataset_hold_obj(dp, 1416 dsl_dataset_phys(ds)->ds_prev_snap_obj, ds, &ds->ds_prev)); 1417 1418 dsl_scan_ds_snapshotted(ds, tx); 1419 1420 dsl_dir_snap_cmtime_update(ds->ds_dir); 1421 1422 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1423 } 1424 1425 static void 1426 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1427 { 1428 dsl_dataset_snapshot_arg_t *ddsa = arg; 1429 dsl_pool_t *dp = dmu_tx_pool(tx); 1430 nvpair_t *pair; 1431 1432 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1433 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1434 dsl_dataset_t *ds; 1435 char *name, *atp; 1436 char dsname[ZFS_MAX_DATASET_NAME_LEN]; 1437 1438 name = nvpair_name(pair); 1439 atp = strchr(name, '@'); 1440 (void) strlcpy(dsname, name, atp - name + 1); 1441 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1442 1443 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1444 if (ddsa->ddsa_props != NULL) { 1445 dsl_props_set_sync_impl(ds->ds_prev, 1446 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1447 } 1448 dsl_dataset_rele(ds, FTAG); 1449 } 1450 } 1451 1452 /* 1453 * The snapshots must all be in the same pool. 1454 * All-or-nothing: if there are any failures, nothing will be modified. 1455 */ 1456 int 1457 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1458 { 1459 dsl_dataset_snapshot_arg_t ddsa; 1460 nvpair_t *pair; 1461 boolean_t needsuspend; 1462 int error; 1463 spa_t *spa; 1464 char *firstname; 1465 nvlist_t *suspended = NULL; 1466 1467 pair = nvlist_next_nvpair(snaps, NULL); 1468 if (pair == NULL) 1469 return (0); 1470 firstname = nvpair_name(pair); 1471 1472 error = spa_open(firstname, &spa, FTAG); 1473 if (error != 0) 1474 return (error); 1475 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1476 spa_close(spa, FTAG); 1477 1478 if (needsuspend) { 1479 suspended = fnvlist_alloc(); 1480 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1481 pair = nvlist_next_nvpair(snaps, pair)) { 1482 char fsname[ZFS_MAX_DATASET_NAME_LEN]; 1483 char *snapname = nvpair_name(pair); 1484 char *atp; 1485 void *cookie; 1486 1487 atp = strchr(snapname, '@'); 1488 if (atp == NULL) { 1489 error = SET_ERROR(EINVAL); 1490 break; 1491 } 1492 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1493 1494 error = zil_suspend(fsname, &cookie); 1495 if (error != 0) 1496 break; 1497 fnvlist_add_uint64(suspended, fsname, 1498 (uintptr_t)cookie); 1499 } 1500 } 1501 1502 ddsa.ddsa_snaps = snaps; 1503 ddsa.ddsa_props = props; 1504 ddsa.ddsa_errors = errors; 1505 ddsa.ddsa_cr = CRED(); 1506 1507 if (error == 0) { 1508 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1509 dsl_dataset_snapshot_sync, &ddsa, 1510 fnvlist_num_pairs(snaps) * 3, ZFS_SPACE_CHECK_NORMAL); 1511 } 1512 1513 if (suspended != NULL) { 1514 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1515 pair = nvlist_next_nvpair(suspended, pair)) { 1516 zil_resume((void *)(uintptr_t) 1517 fnvpair_value_uint64(pair)); 1518 } 1519 fnvlist_free(suspended); 1520 } 1521 1522 return (error); 1523 } 1524 1525 typedef struct dsl_dataset_snapshot_tmp_arg { 1526 const char *ddsta_fsname; 1527 const char *ddsta_snapname; 1528 minor_t ddsta_cleanup_minor; 1529 const char *ddsta_htag; 1530 } dsl_dataset_snapshot_tmp_arg_t; 1531 1532 static int 1533 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1534 { 1535 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1536 dsl_pool_t *dp = dmu_tx_pool(tx); 1537 dsl_dataset_t *ds; 1538 int error; 1539 1540 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1541 if (error != 0) 1542 return (error); 1543 1544 /* NULL cred means no limit check for tmp snapshot */ 1545 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1546 tx, B_FALSE, 0, NULL); 1547 if (error != 0) { 1548 dsl_dataset_rele(ds, FTAG); 1549 return (error); 1550 } 1551 1552 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1553 dsl_dataset_rele(ds, FTAG); 1554 return (SET_ERROR(ENOTSUP)); 1555 } 1556 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1557 B_TRUE, tx); 1558 if (error != 0) { 1559 dsl_dataset_rele(ds, FTAG); 1560 return (error); 1561 } 1562 1563 dsl_dataset_rele(ds, FTAG); 1564 return (0); 1565 } 1566 1567 static void 1568 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1569 { 1570 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1571 dsl_pool_t *dp = dmu_tx_pool(tx); 1572 dsl_dataset_t *ds; 1573 1574 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1575 1576 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1577 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1578 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1579 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1580 1581 dsl_dataset_rele(ds, FTAG); 1582 } 1583 1584 int 1585 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1586 minor_t cleanup_minor, const char *htag) 1587 { 1588 dsl_dataset_snapshot_tmp_arg_t ddsta; 1589 int error; 1590 spa_t *spa; 1591 boolean_t needsuspend; 1592 void *cookie; 1593 1594 ddsta.ddsta_fsname = fsname; 1595 ddsta.ddsta_snapname = snapname; 1596 ddsta.ddsta_cleanup_minor = cleanup_minor; 1597 ddsta.ddsta_htag = htag; 1598 1599 error = spa_open(fsname, &spa, FTAG); 1600 if (error != 0) 1601 return (error); 1602 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1603 spa_close(spa, FTAG); 1604 1605 if (needsuspend) { 1606 error = zil_suspend(fsname, &cookie); 1607 if (error != 0) 1608 return (error); 1609 } 1610 1611 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1612 dsl_dataset_snapshot_tmp_sync, &ddsta, 3, ZFS_SPACE_CHECK_RESERVED); 1613 1614 if (needsuspend) 1615 zil_resume(cookie); 1616 return (error); 1617 } 1618 1619 1620 void 1621 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1622 { 1623 ASSERT(dmu_tx_is_syncing(tx)); 1624 ASSERT(ds->ds_objset != NULL); 1625 ASSERT(dsl_dataset_phys(ds)->ds_next_snap_obj == 0); 1626 1627 /* 1628 * in case we had to change ds_fsid_guid when we opened it, 1629 * sync it out now. 1630 */ 1631 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1632 dsl_dataset_phys(ds)->ds_fsid_guid = ds->ds_fsid_guid; 1633 1634 if (ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] != 0) { 1635 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1636 ds->ds_object, DS_FIELD_RESUME_OBJECT, 8, 1, 1637 &ds->ds_resume_object[tx->tx_txg & TXG_MASK], tx)); 1638 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1639 ds->ds_object, DS_FIELD_RESUME_OFFSET, 8, 1, 1640 &ds->ds_resume_offset[tx->tx_txg & TXG_MASK], tx)); 1641 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1642 ds->ds_object, DS_FIELD_RESUME_BYTES, 8, 1, 1643 &ds->ds_resume_bytes[tx->tx_txg & TXG_MASK], tx)); 1644 ds->ds_resume_object[tx->tx_txg & TXG_MASK] = 0; 1645 ds->ds_resume_offset[tx->tx_txg & TXG_MASK] = 0; 1646 ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] = 0; 1647 } 1648 1649 dmu_objset_sync(ds->ds_objset, zio, tx); 1650 1651 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1652 if (ds->ds_feature_activation_needed[f]) { 1653 if (ds->ds_feature_inuse[f]) 1654 continue; 1655 dsl_dataset_activate_feature(ds->ds_object, f, tx); 1656 ds->ds_feature_inuse[f] = B_TRUE; 1657 } 1658 } 1659 } 1660 1661 static int 1662 deadlist_enqueue_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx) 1663 { 1664 dsl_deadlist_t *dl = arg; 1665 dsl_deadlist_insert(dl, bp, tx); 1666 return (0); 1667 } 1668 1669 void 1670 dsl_dataset_sync_done(dsl_dataset_t *ds, dmu_tx_t *tx) 1671 { 1672 objset_t *os = ds->ds_objset; 1673 1674 bplist_iterate(&ds->ds_pending_deadlist, 1675 deadlist_enqueue_cb, &ds->ds_deadlist, tx); 1676 1677 if (os->os_synced_dnodes != NULL) { 1678 multilist_destroy(os->os_synced_dnodes); 1679 os->os_synced_dnodes = NULL; 1680 } 1681 1682 ASSERT(!dmu_objset_is_dirty(os, dmu_tx_get_txg(tx))); 1683 1684 dmu_buf_rele(ds->ds_dbuf, ds); 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; 1696 1697 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1698 1699 /* 1700 * We use nvlist_alloc() instead of fnvlist_alloc() because the 1701 * latter would allocate the list with NV_UNIQUE_NAME flag. 1702 * As a result, every time a clone name is appended to the list 1703 * it would be (linearly) searched for for a duplicate name. 1704 * We already know that all clone names must be unique and we 1705 * want avoid the quadratic complexity of double-checking that 1706 * because we can have a large number of clones. 1707 */ 1708 VERIFY0(nvlist_alloc(&val, 0, KM_SLEEP)); 1709 1710 /* 1711 * There may be missing entries in ds_next_clones_obj 1712 * due to a bug in a previous version of the code. 1713 * Only trust it if it has the right number of entries. 1714 */ 1715 if (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) { 1716 VERIFY0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1717 &count)); 1718 } 1719 if (count != dsl_dataset_phys(ds)->ds_num_children - 1) 1720 goto fail; 1721 for (zap_cursor_init(&zc, mos, 1722 dsl_dataset_phys(ds)->ds_next_clones_obj); 1723 zap_cursor_retrieve(&zc, &za) == 0; 1724 zap_cursor_advance(&zc)) { 1725 dsl_dataset_t *clone; 1726 char buf[ZFS_MAX_DATASET_NAME_LEN]; 1727 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1728 za.za_first_integer, FTAG, &clone)); 1729 dsl_dir_name(clone->ds_dir, buf); 1730 fnvlist_add_boolean(val, buf); 1731 dsl_dataset_rele(clone, FTAG); 1732 } 1733 zap_cursor_fini(&zc); 1734 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1735 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1736 fail: 1737 nvlist_free(val); 1738 nvlist_free(propval); 1739 } 1740 1741 static void 1742 get_receive_resume_stats(dsl_dataset_t *ds, nvlist_t *nv) 1743 { 1744 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1745 1746 if (dsl_dataset_has_resume_receive_state(ds)) { 1747 char *str; 1748 void *packed; 1749 uint8_t *compressed; 1750 uint64_t val; 1751 nvlist_t *token_nv = fnvlist_alloc(); 1752 size_t packed_size, compressed_size; 1753 1754 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1755 DS_FIELD_RESUME_FROMGUID, sizeof (val), 1, &val) == 0) { 1756 fnvlist_add_uint64(token_nv, "fromguid", val); 1757 } 1758 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1759 DS_FIELD_RESUME_OBJECT, sizeof (val), 1, &val) == 0) { 1760 fnvlist_add_uint64(token_nv, "object", val); 1761 } 1762 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1763 DS_FIELD_RESUME_OFFSET, sizeof (val), 1, &val) == 0) { 1764 fnvlist_add_uint64(token_nv, "offset", val); 1765 } 1766 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1767 DS_FIELD_RESUME_BYTES, sizeof (val), 1, &val) == 0) { 1768 fnvlist_add_uint64(token_nv, "bytes", val); 1769 } 1770 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1771 DS_FIELD_RESUME_TOGUID, sizeof (val), 1, &val) == 0) { 1772 fnvlist_add_uint64(token_nv, "toguid", val); 1773 } 1774 char buf[256]; 1775 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1776 DS_FIELD_RESUME_TONAME, 1, sizeof (buf), buf) == 0) { 1777 fnvlist_add_string(token_nv, "toname", buf); 1778 } 1779 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1780 DS_FIELD_RESUME_LARGEBLOCK) == 0) { 1781 fnvlist_add_boolean(token_nv, "largeblockok"); 1782 } 1783 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1784 DS_FIELD_RESUME_EMBEDOK) == 0) { 1785 fnvlist_add_boolean(token_nv, "embedok"); 1786 } 1787 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1788 DS_FIELD_RESUME_COMPRESSOK) == 0) { 1789 fnvlist_add_boolean(token_nv, "compressok"); 1790 } 1791 packed = fnvlist_pack(token_nv, &packed_size); 1792 fnvlist_free(token_nv); 1793 compressed = kmem_alloc(packed_size, KM_SLEEP); 1794 1795 compressed_size = gzip_compress(packed, compressed, 1796 packed_size, packed_size, 6); 1797 1798 zio_cksum_t cksum; 1799 fletcher_4_native(compressed, compressed_size, NULL, &cksum); 1800 1801 str = kmem_alloc(compressed_size * 2 + 1, KM_SLEEP); 1802 for (int i = 0; i < compressed_size; i++) { 1803 (void) sprintf(str + i * 2, "%02x", compressed[i]); 1804 } 1805 str[compressed_size * 2] = '\0'; 1806 char *propval = kmem_asprintf("%u-%llx-%llx-%s", 1807 ZFS_SEND_RESUME_TOKEN_VERSION, 1808 (longlong_t)cksum.zc_word[0], 1809 (longlong_t)packed_size, str); 1810 dsl_prop_nvlist_add_string(nv, 1811 ZFS_PROP_RECEIVE_RESUME_TOKEN, propval); 1812 kmem_free(packed, packed_size); 1813 kmem_free(str, compressed_size * 2 + 1); 1814 kmem_free(compressed, packed_size); 1815 strfree(propval); 1816 } 1817 } 1818 1819 void 1820 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1821 { 1822 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1823 uint64_t refd, avail, uobjs, aobjs, ratio; 1824 1825 ASSERT(dsl_pool_config_held(dp)); 1826 1827 ratio = dsl_dataset_phys(ds)->ds_compressed_bytes == 0 ? 100 : 1828 (dsl_dataset_phys(ds)->ds_uncompressed_bytes * 100 / 1829 dsl_dataset_phys(ds)->ds_compressed_bytes); 1830 1831 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1832 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1833 dsl_dataset_phys(ds)->ds_uncompressed_bytes); 1834 1835 if (ds->ds_is_snapshot) { 1836 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1837 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1838 dsl_dataset_phys(ds)->ds_unique_bytes); 1839 get_clones_stat(ds, nv); 1840 } else { 1841 if (ds->ds_prev != NULL && ds->ds_prev != dp->dp_origin_snap) { 1842 char buf[ZFS_MAX_DATASET_NAME_LEN]; 1843 dsl_dataset_name(ds->ds_prev, buf); 1844 dsl_prop_nvlist_add_string(nv, ZFS_PROP_PREV_SNAP, buf); 1845 } 1846 1847 dsl_dir_stats(ds->ds_dir, nv); 1848 } 1849 1850 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1851 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1852 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1853 1854 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1855 dsl_dataset_phys(ds)->ds_creation_time); 1856 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1857 dsl_dataset_phys(ds)->ds_creation_txg); 1858 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1859 ds->ds_quota); 1860 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1861 ds->ds_reserved); 1862 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1863 dsl_dataset_phys(ds)->ds_guid); 1864 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1865 dsl_dataset_phys(ds)->ds_unique_bytes); 1866 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1867 ds->ds_object); 1868 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1869 ds->ds_userrefs); 1870 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1871 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1872 1873 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 1874 uint64_t written, comp, uncomp; 1875 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1876 dsl_dataset_t *prev; 1877 1878 int err = dsl_dataset_hold_obj(dp, 1879 dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &prev); 1880 if (err == 0) { 1881 err = dsl_dataset_space_written(prev, ds, &written, 1882 &comp, &uncomp); 1883 dsl_dataset_rele(prev, FTAG); 1884 if (err == 0) { 1885 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1886 written); 1887 } 1888 } 1889 } 1890 1891 if (!dsl_dataset_is_snapshot(ds)) { 1892 /* 1893 * A failed "newfs" (e.g. full) resumable receive leaves 1894 * the stats set on this dataset. Check here for the prop. 1895 */ 1896 get_receive_resume_stats(ds, nv); 1897 1898 /* 1899 * A failed incremental resumable receive leaves the 1900 * stats set on our child named "%recv". Check the child 1901 * for the prop. 1902 */ 1903 /* 6 extra bytes for /%recv */ 1904 char recvname[ZFS_MAX_DATASET_NAME_LEN + 6]; 1905 dsl_dataset_t *recv_ds; 1906 dsl_dataset_name(ds, recvname); 1907 if (strlcat(recvname, "/", sizeof (recvname)) < 1908 sizeof (recvname) && 1909 strlcat(recvname, recv_clone_name, sizeof (recvname)) < 1910 sizeof (recvname) && 1911 dsl_dataset_hold(dp, recvname, FTAG, &recv_ds) == 0) { 1912 get_receive_resume_stats(recv_ds, nv); 1913 dsl_dataset_rele(recv_ds, FTAG); 1914 } 1915 } 1916 } 1917 1918 void 1919 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1920 { 1921 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1922 ASSERT(dsl_pool_config_held(dp)); 1923 1924 stat->dds_creation_txg = dsl_dataset_phys(ds)->ds_creation_txg; 1925 stat->dds_inconsistent = 1926 dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT; 1927 stat->dds_guid = dsl_dataset_phys(ds)->ds_guid; 1928 stat->dds_origin[0] = '\0'; 1929 if (ds->ds_is_snapshot) { 1930 stat->dds_is_snapshot = B_TRUE; 1931 stat->dds_num_clones = 1932 dsl_dataset_phys(ds)->ds_num_children - 1; 1933 } else { 1934 stat->dds_is_snapshot = B_FALSE; 1935 stat->dds_num_clones = 0; 1936 1937 if (dsl_dir_is_clone(ds->ds_dir)) { 1938 dsl_dataset_t *ods; 1939 1940 VERIFY0(dsl_dataset_hold_obj(dp, 1941 dsl_dir_phys(ds->ds_dir)->dd_origin_obj, 1942 FTAG, &ods)); 1943 dsl_dataset_name(ods, stat->dds_origin); 1944 dsl_dataset_rele(ods, FTAG); 1945 } 1946 } 1947 } 1948 1949 uint64_t 1950 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1951 { 1952 return (ds->ds_fsid_guid); 1953 } 1954 1955 void 1956 dsl_dataset_space(dsl_dataset_t *ds, 1957 uint64_t *refdbytesp, uint64_t *availbytesp, 1958 uint64_t *usedobjsp, uint64_t *availobjsp) 1959 { 1960 *refdbytesp = dsl_dataset_phys(ds)->ds_referenced_bytes; 1961 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1962 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) 1963 *availbytesp += 1964 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes; 1965 if (ds->ds_quota != 0) { 1966 /* 1967 * Adjust available bytes according to refquota 1968 */ 1969 if (*refdbytesp < ds->ds_quota) 1970 *availbytesp = MIN(*availbytesp, 1971 ds->ds_quota - *refdbytesp); 1972 else 1973 *availbytesp = 0; 1974 } 1975 rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); 1976 *usedobjsp = BP_GET_FILL(&dsl_dataset_phys(ds)->ds_bp); 1977 rrw_exit(&ds->ds_bp_rwlock, FTAG); 1978 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1979 } 1980 1981 boolean_t 1982 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1983 { 1984 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1985 uint64_t birth; 1986 1987 ASSERT(dsl_pool_config_held(dp)); 1988 if (snap == NULL) 1989 return (B_FALSE); 1990 rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); 1991 birth = dsl_dataset_get_blkptr(ds)->blk_birth; 1992 rrw_exit(&ds->ds_bp_rwlock, FTAG); 1993 if (birth > dsl_dataset_phys(snap)->ds_creation_txg) { 1994 objset_t *os, *os_snap; 1995 /* 1996 * It may be that only the ZIL differs, because it was 1997 * reset in the head. Don't count that as being 1998 * modified. 1999 */ 2000 if (dmu_objset_from_ds(ds, &os) != 0) 2001 return (B_TRUE); 2002 if (dmu_objset_from_ds(snap, &os_snap) != 0) 2003 return (B_TRUE); 2004 return (bcmp(&os->os_phys->os_meta_dnode, 2005 &os_snap->os_phys->os_meta_dnode, 2006 sizeof (os->os_phys->os_meta_dnode)) != 0); 2007 } 2008 return (B_FALSE); 2009 } 2010 2011 typedef struct dsl_dataset_rename_snapshot_arg { 2012 const char *ddrsa_fsname; 2013 const char *ddrsa_oldsnapname; 2014 const char *ddrsa_newsnapname; 2015 boolean_t ddrsa_recursive; 2016 dmu_tx_t *ddrsa_tx; 2017 } dsl_dataset_rename_snapshot_arg_t; 2018 2019 /* ARGSUSED */ 2020 static int 2021 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 2022 dsl_dataset_t *hds, void *arg) 2023 { 2024 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2025 int error; 2026 uint64_t val; 2027 2028 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2029 if (error != 0) { 2030 /* ignore nonexistent snapshots */ 2031 return (error == ENOENT ? 0 : error); 2032 } 2033 2034 /* new name should not exist */ 2035 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 2036 if (error == 0) 2037 error = SET_ERROR(EEXIST); 2038 else if (error == ENOENT) 2039 error = 0; 2040 2041 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2042 if (dsl_dir_namelen(hds->ds_dir) + 1 + 2043 strlen(ddrsa->ddrsa_newsnapname) >= ZFS_MAX_DATASET_NAME_LEN) 2044 error = SET_ERROR(ENAMETOOLONG); 2045 2046 return (error); 2047 } 2048 2049 static int 2050 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 2051 { 2052 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2053 dsl_pool_t *dp = dmu_tx_pool(tx); 2054 dsl_dataset_t *hds; 2055 int error; 2056 2057 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 2058 if (error != 0) 2059 return (error); 2060 2061 if (ddrsa->ddrsa_recursive) { 2062 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2063 dsl_dataset_rename_snapshot_check_impl, ddrsa, 2064 DS_FIND_CHILDREN); 2065 } else { 2066 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 2067 } 2068 dsl_dataset_rele(hds, FTAG); 2069 return (error); 2070 } 2071 2072 static int 2073 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 2074 dsl_dataset_t *hds, void *arg) 2075 { 2076 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2077 dsl_dataset_t *ds; 2078 uint64_t val; 2079 dmu_tx_t *tx = ddrsa->ddrsa_tx; 2080 int error; 2081 2082 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2083 ASSERT(error == 0 || error == ENOENT); 2084 if (error == ENOENT) { 2085 /* ignore nonexistent snapshots */ 2086 return (0); 2087 } 2088 2089 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 2090 2091 /* log before we change the name */ 2092 spa_history_log_internal_ds(ds, "rename", tx, 2093 "-> @%s", ddrsa->ddrsa_newsnapname); 2094 2095 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx, 2096 B_FALSE)); 2097 mutex_enter(&ds->ds_lock); 2098 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 2099 mutex_exit(&ds->ds_lock); 2100 VERIFY0(zap_add(dp->dp_meta_objset, 2101 dsl_dataset_phys(hds)->ds_snapnames_zapobj, 2102 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 2103 2104 dsl_dataset_rele(ds, FTAG); 2105 return (0); 2106 } 2107 2108 static void 2109 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 2110 { 2111 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2112 dsl_pool_t *dp = dmu_tx_pool(tx); 2113 dsl_dataset_t *hds; 2114 2115 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 2116 ddrsa->ddrsa_tx = tx; 2117 if (ddrsa->ddrsa_recursive) { 2118 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2119 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 2120 DS_FIND_CHILDREN)); 2121 } else { 2122 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 2123 } 2124 dsl_dataset_rele(hds, FTAG); 2125 } 2126 2127 int 2128 dsl_dataset_rename_snapshot(const char *fsname, 2129 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 2130 { 2131 dsl_dataset_rename_snapshot_arg_t ddrsa; 2132 2133 ddrsa.ddrsa_fsname = fsname; 2134 ddrsa.ddrsa_oldsnapname = oldsnapname; 2135 ddrsa.ddrsa_newsnapname = newsnapname; 2136 ddrsa.ddrsa_recursive = recursive; 2137 2138 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 2139 dsl_dataset_rename_snapshot_sync, &ddrsa, 2140 1, ZFS_SPACE_CHECK_RESERVED)); 2141 } 2142 2143 /* 2144 * If we're doing an ownership handoff, we need to make sure that there is 2145 * only one long hold on the dataset. We're not allowed to change anything here 2146 * so we don't permanently release the long hold or regular hold here. We want 2147 * to do this only when syncing to avoid the dataset unexpectedly going away 2148 * when we release the long hold. 2149 */ 2150 static int 2151 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 2152 { 2153 boolean_t held; 2154 2155 if (!dmu_tx_is_syncing(tx)) 2156 return (0); 2157 2158 if (owner != NULL) { 2159 VERIFY3P(ds->ds_owner, ==, owner); 2160 dsl_dataset_long_rele(ds, owner); 2161 } 2162 2163 held = dsl_dataset_long_held(ds); 2164 2165 if (owner != NULL) 2166 dsl_dataset_long_hold(ds, owner); 2167 2168 if (held) 2169 return (SET_ERROR(EBUSY)); 2170 2171 return (0); 2172 } 2173 2174 typedef struct dsl_dataset_rollback_arg { 2175 const char *ddra_fsname; 2176 void *ddra_owner; 2177 nvlist_t *ddra_result; 2178 } dsl_dataset_rollback_arg_t; 2179 2180 static int 2181 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 2182 { 2183 dsl_dataset_rollback_arg_t *ddra = arg; 2184 dsl_pool_t *dp = dmu_tx_pool(tx); 2185 dsl_dataset_t *ds; 2186 int64_t unused_refres_delta; 2187 int error; 2188 2189 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 2190 if (error != 0) 2191 return (error); 2192 2193 /* must not be a snapshot */ 2194 if (ds->ds_is_snapshot) { 2195 dsl_dataset_rele(ds, FTAG); 2196 return (SET_ERROR(EINVAL)); 2197 } 2198 2199 /* must have a most recent snapshot */ 2200 if (dsl_dataset_phys(ds)->ds_prev_snap_txg < TXG_INITIAL) { 2201 dsl_dataset_rele(ds, FTAG); 2202 return (SET_ERROR(EINVAL)); 2203 } 2204 2205 /* 2206 * No rollback to a snapshot created in the current txg, because 2207 * the rollback may dirty the dataset and create blocks that are 2208 * not reachable from the rootbp while having a birth txg that 2209 * falls into the snapshot's range. 2210 */ 2211 if (dmu_tx_is_syncing(tx) && 2212 dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg) { 2213 dsl_dataset_rele(ds, FTAG); 2214 return (SET_ERROR(EAGAIN)); 2215 } 2216 2217 /* must not have any bookmarks after the most recent snapshot */ 2218 nvlist_t *proprequest = fnvlist_alloc(); 2219 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2220 nvlist_t *bookmarks = fnvlist_alloc(); 2221 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks); 2222 fnvlist_free(proprequest); 2223 if (error != 0) 2224 return (error); 2225 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL); 2226 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) { 2227 nvlist_t *valuenv = 2228 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair), 2229 zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2230 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value"); 2231 if (createtxg > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 2232 fnvlist_free(bookmarks); 2233 dsl_dataset_rele(ds, FTAG); 2234 return (SET_ERROR(EEXIST)); 2235 } 2236 } 2237 fnvlist_free(bookmarks); 2238 2239 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 2240 if (error != 0) { 2241 dsl_dataset_rele(ds, FTAG); 2242 return (error); 2243 } 2244 2245 /* 2246 * Check if the snap we are rolling back to uses more than 2247 * the refquota. 2248 */ 2249 if (ds->ds_quota != 0 && 2250 dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes > ds->ds_quota) { 2251 dsl_dataset_rele(ds, FTAG); 2252 return (SET_ERROR(EDQUOT)); 2253 } 2254 2255 /* 2256 * When we do the clone swap, we will temporarily use more space 2257 * due to the refreservation (the head will no longer have any 2258 * unique space, so the entire amount of the refreservation will need 2259 * to be free). We will immediately destroy the clone, freeing 2260 * this space, but the freeing happens over many txg's. 2261 */ 2262 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 2263 dsl_dataset_phys(ds)->ds_unique_bytes); 2264 2265 if (unused_refres_delta > 0 && 2266 unused_refres_delta > 2267 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 2268 dsl_dataset_rele(ds, FTAG); 2269 return (SET_ERROR(ENOSPC)); 2270 } 2271 2272 dsl_dataset_rele(ds, FTAG); 2273 return (0); 2274 } 2275 2276 static void 2277 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 2278 { 2279 dsl_dataset_rollback_arg_t *ddra = arg; 2280 dsl_pool_t *dp = dmu_tx_pool(tx); 2281 dsl_dataset_t *ds, *clone; 2282 uint64_t cloneobj; 2283 char namebuf[ZFS_MAX_DATASET_NAME_LEN]; 2284 2285 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 2286 2287 dsl_dataset_name(ds->ds_prev, namebuf); 2288 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 2289 2290 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 2291 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 2292 2293 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 2294 2295 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 2296 dsl_dataset_zero_zil(ds, tx); 2297 2298 dsl_destroy_head_sync_impl(clone, tx); 2299 2300 dsl_dataset_rele(clone, FTAG); 2301 dsl_dataset_rele(ds, FTAG); 2302 } 2303 2304 /* 2305 * Rolls back the given filesystem or volume to the most recent snapshot. 2306 * The name of the most recent snapshot will be returned under key "target" 2307 * in the result nvlist. 2308 * 2309 * If owner != NULL: 2310 * - The existing dataset MUST be owned by the specified owner at entry 2311 * - Upon return, dataset will still be held by the same owner, whether we 2312 * succeed or not. 2313 * 2314 * This mode is required any time the existing filesystem is mounted. See 2315 * notes above zfs_suspend_fs() for further details. 2316 */ 2317 int 2318 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result) 2319 { 2320 dsl_dataset_rollback_arg_t ddra; 2321 2322 ddra.ddra_fsname = fsname; 2323 ddra.ddra_owner = owner; 2324 ddra.ddra_result = result; 2325 2326 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 2327 dsl_dataset_rollback_sync, &ddra, 2328 1, ZFS_SPACE_CHECK_RESERVED)); 2329 } 2330 2331 struct promotenode { 2332 list_node_t link; 2333 dsl_dataset_t *ds; 2334 }; 2335 2336 typedef struct dsl_dataset_promote_arg { 2337 const char *ddpa_clonename; 2338 dsl_dataset_t *ddpa_clone; 2339 list_t shared_snaps, origin_snaps, clone_snaps; 2340 dsl_dataset_t *origin_origin; /* origin of the origin */ 2341 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2342 char *err_ds; 2343 cred_t *cr; 2344 } dsl_dataset_promote_arg_t; 2345 2346 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2347 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 2348 void *tag); 2349 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 2350 2351 static int 2352 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 2353 { 2354 dsl_dataset_promote_arg_t *ddpa = arg; 2355 dsl_pool_t *dp = dmu_tx_pool(tx); 2356 dsl_dataset_t *hds; 2357 struct promotenode *snap; 2358 dsl_dataset_t *origin_ds; 2359 int err; 2360 uint64_t unused; 2361 uint64_t ss_mv_cnt; 2362 size_t max_snap_len; 2363 2364 err = promote_hold(ddpa, dp, FTAG); 2365 if (err != 0) 2366 return (err); 2367 2368 hds = ddpa->ddpa_clone; 2369 max_snap_len = MAXNAMELEN - strlen(ddpa->ddpa_clonename) - 1; 2370 2371 if (dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE) { 2372 promote_rele(ddpa, FTAG); 2373 return (SET_ERROR(EXDEV)); 2374 } 2375 2376 /* 2377 * Compute and check the amount of space to transfer. Since this is 2378 * so expensive, don't do the preliminary check. 2379 */ 2380 if (!dmu_tx_is_syncing(tx)) { 2381 promote_rele(ddpa, FTAG); 2382 return (0); 2383 } 2384 2385 snap = list_head(&ddpa->shared_snaps); 2386 origin_ds = snap->ds; 2387 2388 /* compute origin's new unique space */ 2389 snap = list_tail(&ddpa->clone_snaps); 2390 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2391 origin_ds->ds_object); 2392 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2393 dsl_dataset_phys(origin_ds)->ds_prev_snap_txg, UINT64_MAX, 2394 &ddpa->unique, &unused, &unused); 2395 2396 /* 2397 * Walk the snapshots that we are moving 2398 * 2399 * Compute space to transfer. Consider the incremental changes 2400 * to used by each snapshot: 2401 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2402 * So each snapshot gave birth to: 2403 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2404 * So a sequence would look like: 2405 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2406 * Which simplifies to: 2407 * uN + kN + kN-1 + ... + k1 + k0 2408 * Note however, if we stop before we reach the ORIGIN we get: 2409 * uN + kN + kN-1 + ... + kM - uM-1 2410 */ 2411 ss_mv_cnt = 0; 2412 ddpa->used = dsl_dataset_phys(origin_ds)->ds_referenced_bytes; 2413 ddpa->comp = dsl_dataset_phys(origin_ds)->ds_compressed_bytes; 2414 ddpa->uncomp = dsl_dataset_phys(origin_ds)->ds_uncompressed_bytes; 2415 for (snap = list_head(&ddpa->shared_snaps); snap; 2416 snap = list_next(&ddpa->shared_snaps, snap)) { 2417 uint64_t val, dlused, dlcomp, dluncomp; 2418 dsl_dataset_t *ds = snap->ds; 2419 2420 ss_mv_cnt++; 2421 2422 /* 2423 * If there are long holds, we won't be able to evict 2424 * the objset. 2425 */ 2426 if (dsl_dataset_long_held(ds)) { 2427 err = SET_ERROR(EBUSY); 2428 goto out; 2429 } 2430 2431 /* Check that the snapshot name does not conflict */ 2432 VERIFY0(dsl_dataset_get_snapname(ds)); 2433 if (strlen(ds->ds_snapname) >= max_snap_len) { 2434 err = SET_ERROR(ENAMETOOLONG); 2435 goto out; 2436 } 2437 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2438 if (err == 0) { 2439 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 2440 err = SET_ERROR(EEXIST); 2441 goto out; 2442 } 2443 if (err != ENOENT) 2444 goto out; 2445 2446 /* The very first snapshot does not have a deadlist */ 2447 if (dsl_dataset_phys(ds)->ds_prev_snap_obj == 0) 2448 continue; 2449 2450 dsl_deadlist_space(&ds->ds_deadlist, 2451 &dlused, &dlcomp, &dluncomp); 2452 ddpa->used += dlused; 2453 ddpa->comp += dlcomp; 2454 ddpa->uncomp += dluncomp; 2455 } 2456 2457 /* 2458 * If we are a clone of a clone then we never reached ORIGIN, 2459 * so we need to subtract out the clone origin's used space. 2460 */ 2461 if (ddpa->origin_origin) { 2462 ddpa->used -= 2463 dsl_dataset_phys(ddpa->origin_origin)->ds_referenced_bytes; 2464 ddpa->comp -= 2465 dsl_dataset_phys(ddpa->origin_origin)->ds_compressed_bytes; 2466 ddpa->uncomp -= 2467 dsl_dataset_phys(ddpa->origin_origin)-> 2468 ds_uncompressed_bytes; 2469 } 2470 2471 /* Check that there is enough space and limit headroom here */ 2472 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2473 0, ss_mv_cnt, ddpa->used, ddpa->cr); 2474 if (err != 0) 2475 goto out; 2476 2477 /* 2478 * Compute the amounts of space that will be used by snapshots 2479 * after the promotion (for both origin and clone). For each, 2480 * it is the amount of space that will be on all of their 2481 * deadlists (that was not born before their new origin). 2482 */ 2483 if (dsl_dir_phys(hds->ds_dir)->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2484 uint64_t space; 2485 2486 /* 2487 * Note, typically this will not be a clone of a clone, 2488 * so dd_origin_txg will be < TXG_INITIAL, so 2489 * these snaplist_space() -> dsl_deadlist_space_range() 2490 * calls will be fast because they do not have to 2491 * iterate over all bps. 2492 */ 2493 snap = list_head(&ddpa->origin_snaps); 2494 err = snaplist_space(&ddpa->shared_snaps, 2495 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 2496 if (err != 0) 2497 goto out; 2498 2499 err = snaplist_space(&ddpa->clone_snaps, 2500 snap->ds->ds_dir->dd_origin_txg, &space); 2501 if (err != 0) 2502 goto out; 2503 ddpa->cloneusedsnap += space; 2504 } 2505 if (dsl_dir_phys(origin_ds->ds_dir)->dd_flags & 2506 DD_FLAG_USED_BREAKDOWN) { 2507 err = snaplist_space(&ddpa->origin_snaps, 2508 dsl_dataset_phys(origin_ds)->ds_creation_txg, 2509 &ddpa->originusedsnap); 2510 if (err != 0) 2511 goto out; 2512 } 2513 2514 out: 2515 promote_rele(ddpa, FTAG); 2516 return (err); 2517 } 2518 2519 static void 2520 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2521 { 2522 dsl_dataset_promote_arg_t *ddpa = arg; 2523 dsl_pool_t *dp = dmu_tx_pool(tx); 2524 dsl_dataset_t *hds; 2525 struct promotenode *snap; 2526 dsl_dataset_t *origin_ds; 2527 dsl_dataset_t *origin_head; 2528 dsl_dir_t *dd; 2529 dsl_dir_t *odd = NULL; 2530 uint64_t oldnext_obj; 2531 int64_t delta; 2532 2533 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2534 hds = ddpa->ddpa_clone; 2535 2536 ASSERT0(dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE); 2537 2538 snap = list_head(&ddpa->shared_snaps); 2539 origin_ds = snap->ds; 2540 dd = hds->ds_dir; 2541 2542 snap = list_head(&ddpa->origin_snaps); 2543 origin_head = snap->ds; 2544 2545 /* 2546 * We need to explicitly open odd, since origin_ds's dd will be 2547 * changing. 2548 */ 2549 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2550 NULL, FTAG, &odd)); 2551 2552 /* change origin's next snap */ 2553 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2554 oldnext_obj = dsl_dataset_phys(origin_ds)->ds_next_snap_obj; 2555 snap = list_tail(&ddpa->clone_snaps); 2556 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2557 origin_ds->ds_object); 2558 dsl_dataset_phys(origin_ds)->ds_next_snap_obj = snap->ds->ds_object; 2559 2560 /* change the origin's next clone */ 2561 if (dsl_dataset_phys(origin_ds)->ds_next_clones_obj) { 2562 dsl_dataset_remove_from_next_clones(origin_ds, 2563 snap->ds->ds_object, tx); 2564 VERIFY0(zap_add_int(dp->dp_meta_objset, 2565 dsl_dataset_phys(origin_ds)->ds_next_clones_obj, 2566 oldnext_obj, tx)); 2567 } 2568 2569 /* change origin */ 2570 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2571 ASSERT3U(dsl_dir_phys(dd)->dd_origin_obj, ==, origin_ds->ds_object); 2572 dsl_dir_phys(dd)->dd_origin_obj = dsl_dir_phys(odd)->dd_origin_obj; 2573 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2574 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2575 dsl_dir_phys(odd)->dd_origin_obj = origin_ds->ds_object; 2576 origin_head->ds_dir->dd_origin_txg = 2577 dsl_dataset_phys(origin_ds)->ds_creation_txg; 2578 2579 /* change dd_clone entries */ 2580 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2581 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2582 dsl_dir_phys(odd)->dd_clones, hds->ds_object, tx)); 2583 VERIFY0(zap_add_int(dp->dp_meta_objset, 2584 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2585 hds->ds_object, tx)); 2586 2587 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2588 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2589 origin_head->ds_object, tx)); 2590 if (dsl_dir_phys(dd)->dd_clones == 0) { 2591 dsl_dir_phys(dd)->dd_clones = 2592 zap_create(dp->dp_meta_objset, DMU_OT_DSL_CLONES, 2593 DMU_OT_NONE, 0, tx); 2594 } 2595 VERIFY0(zap_add_int(dp->dp_meta_objset, 2596 dsl_dir_phys(dd)->dd_clones, origin_head->ds_object, tx)); 2597 } 2598 2599 /* move snapshots to this dir */ 2600 for (snap = list_head(&ddpa->shared_snaps); snap; 2601 snap = list_next(&ddpa->shared_snaps, snap)) { 2602 dsl_dataset_t *ds = snap->ds; 2603 2604 /* 2605 * Property callbacks are registered to a particular 2606 * dsl_dir. Since ours is changing, evict the objset 2607 * so that they will be unregistered from the old dsl_dir. 2608 */ 2609 if (ds->ds_objset) { 2610 dmu_objset_evict(ds->ds_objset); 2611 ds->ds_objset = NULL; 2612 } 2613 2614 /* move snap name entry */ 2615 VERIFY0(dsl_dataset_get_snapname(ds)); 2616 VERIFY0(dsl_dataset_snap_remove(origin_head, 2617 ds->ds_snapname, tx, B_TRUE)); 2618 VERIFY0(zap_add(dp->dp_meta_objset, 2619 dsl_dataset_phys(hds)->ds_snapnames_zapobj, ds->ds_snapname, 2620 8, 1, &ds->ds_object, tx)); 2621 dsl_fs_ss_count_adjust(hds->ds_dir, 1, 2622 DD_FIELD_SNAPSHOT_COUNT, tx); 2623 2624 /* change containing dsl_dir */ 2625 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2626 ASSERT3U(dsl_dataset_phys(ds)->ds_dir_obj, ==, odd->dd_object); 2627 dsl_dataset_phys(ds)->ds_dir_obj = dd->dd_object; 2628 ASSERT3P(ds->ds_dir, ==, odd); 2629 dsl_dir_rele(ds->ds_dir, ds); 2630 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2631 NULL, ds, &ds->ds_dir)); 2632 2633 /* move any clone references */ 2634 if (dsl_dataset_phys(ds)->ds_next_clones_obj && 2635 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2636 zap_cursor_t zc; 2637 zap_attribute_t za; 2638 2639 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2640 dsl_dataset_phys(ds)->ds_next_clones_obj); 2641 zap_cursor_retrieve(&zc, &za) == 0; 2642 zap_cursor_advance(&zc)) { 2643 dsl_dataset_t *cnds; 2644 uint64_t o; 2645 2646 if (za.za_first_integer == oldnext_obj) { 2647 /* 2648 * We've already moved the 2649 * origin's reference. 2650 */ 2651 continue; 2652 } 2653 2654 VERIFY0(dsl_dataset_hold_obj(dp, 2655 za.za_first_integer, FTAG, &cnds)); 2656 o = dsl_dir_phys(cnds->ds_dir)-> 2657 dd_head_dataset_obj; 2658 2659 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2660 dsl_dir_phys(odd)->dd_clones, o, tx)); 2661 VERIFY0(zap_add_int(dp->dp_meta_objset, 2662 dsl_dir_phys(dd)->dd_clones, o, tx)); 2663 dsl_dataset_rele(cnds, FTAG); 2664 } 2665 zap_cursor_fini(&zc); 2666 } 2667 2668 ASSERT(!dsl_prop_hascb(ds)); 2669 } 2670 2671 /* 2672 * Change space accounting. 2673 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2674 * both be valid, or both be 0 (resulting in delta == 0). This 2675 * is true for each of {clone,origin} independently. 2676 */ 2677 2678 delta = ddpa->cloneusedsnap - 2679 dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_SNAP]; 2680 ASSERT3S(delta, >=, 0); 2681 ASSERT3U(ddpa->used, >=, delta); 2682 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2683 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2684 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2685 2686 delta = ddpa->originusedsnap - 2687 dsl_dir_phys(odd)->dd_used_breakdown[DD_USED_SNAP]; 2688 ASSERT3S(delta, <=, 0); 2689 ASSERT3U(ddpa->used, >=, -delta); 2690 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2691 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2692 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2693 2694 dsl_dataset_phys(origin_ds)->ds_unique_bytes = ddpa->unique; 2695 2696 /* log history record */ 2697 spa_history_log_internal_ds(hds, "promote", tx, ""); 2698 2699 dsl_dir_rele(odd, FTAG); 2700 promote_rele(ddpa, FTAG); 2701 } 2702 2703 /* 2704 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2705 * (exclusive) and last_obj (inclusive). The list will be in reverse 2706 * order (last_obj will be the list_head()). If first_obj == 0, do all 2707 * snapshots back to this dataset's origin. 2708 */ 2709 static int 2710 snaplist_make(dsl_pool_t *dp, 2711 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2712 { 2713 uint64_t obj = last_obj; 2714 2715 list_create(l, sizeof (struct promotenode), 2716 offsetof(struct promotenode, link)); 2717 2718 while (obj != first_obj) { 2719 dsl_dataset_t *ds; 2720 struct promotenode *snap; 2721 int err; 2722 2723 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2724 ASSERT(err != ENOENT); 2725 if (err != 0) 2726 return (err); 2727 2728 if (first_obj == 0) 2729 first_obj = dsl_dir_phys(ds->ds_dir)->dd_origin_obj; 2730 2731 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2732 snap->ds = ds; 2733 list_insert_tail(l, snap); 2734 obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 2735 } 2736 2737 return (0); 2738 } 2739 2740 static int 2741 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2742 { 2743 struct promotenode *snap; 2744 2745 *spacep = 0; 2746 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2747 uint64_t used, comp, uncomp; 2748 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2749 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2750 *spacep += used; 2751 } 2752 return (0); 2753 } 2754 2755 static void 2756 snaplist_destroy(list_t *l, void *tag) 2757 { 2758 struct promotenode *snap; 2759 2760 if (l == NULL || !list_link_active(&l->list_head)) 2761 return; 2762 2763 while ((snap = list_tail(l)) != NULL) { 2764 list_remove(l, snap); 2765 dsl_dataset_rele(snap->ds, tag); 2766 kmem_free(snap, sizeof (*snap)); 2767 } 2768 list_destroy(l); 2769 } 2770 2771 static int 2772 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2773 { 2774 int error; 2775 dsl_dir_t *dd; 2776 struct promotenode *snap; 2777 2778 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2779 &ddpa->ddpa_clone); 2780 if (error != 0) 2781 return (error); 2782 dd = ddpa->ddpa_clone->ds_dir; 2783 2784 if (ddpa->ddpa_clone->ds_is_snapshot || 2785 !dsl_dir_is_clone(dd)) { 2786 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2787 return (SET_ERROR(EINVAL)); 2788 } 2789 2790 error = snaplist_make(dp, 0, dsl_dir_phys(dd)->dd_origin_obj, 2791 &ddpa->shared_snaps, tag); 2792 if (error != 0) 2793 goto out; 2794 2795 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2796 &ddpa->clone_snaps, tag); 2797 if (error != 0) 2798 goto out; 2799 2800 snap = list_head(&ddpa->shared_snaps); 2801 ASSERT3U(snap->ds->ds_object, ==, dsl_dir_phys(dd)->dd_origin_obj); 2802 error = snaplist_make(dp, dsl_dir_phys(dd)->dd_origin_obj, 2803 dsl_dir_phys(snap->ds->ds_dir)->dd_head_dataset_obj, 2804 &ddpa->origin_snaps, tag); 2805 if (error != 0) 2806 goto out; 2807 2808 if (dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj != 0) { 2809 error = dsl_dataset_hold_obj(dp, 2810 dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj, 2811 tag, &ddpa->origin_origin); 2812 if (error != 0) 2813 goto out; 2814 } 2815 out: 2816 if (error != 0) 2817 promote_rele(ddpa, tag); 2818 return (error); 2819 } 2820 2821 static void 2822 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2823 { 2824 snaplist_destroy(&ddpa->shared_snaps, tag); 2825 snaplist_destroy(&ddpa->clone_snaps, tag); 2826 snaplist_destroy(&ddpa->origin_snaps, tag); 2827 if (ddpa->origin_origin != NULL) 2828 dsl_dataset_rele(ddpa->origin_origin, tag); 2829 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2830 } 2831 2832 /* 2833 * Promote a clone. 2834 * 2835 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2836 * in with the name. (It must be at least ZFS_MAX_DATASET_NAME_LEN bytes long.) 2837 */ 2838 int 2839 dsl_dataset_promote(const char *name, char *conflsnap) 2840 { 2841 dsl_dataset_promote_arg_t ddpa = { 0 }; 2842 uint64_t numsnaps; 2843 int error; 2844 objset_t *os; 2845 2846 /* 2847 * We will modify space proportional to the number of 2848 * snapshots. Compute numsnaps. 2849 */ 2850 error = dmu_objset_hold(name, FTAG, &os); 2851 if (error != 0) 2852 return (error); 2853 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2854 dsl_dataset_phys(dmu_objset_ds(os))->ds_snapnames_zapobj, 2855 &numsnaps); 2856 dmu_objset_rele(os, FTAG); 2857 if (error != 0) 2858 return (error); 2859 2860 ddpa.ddpa_clonename = name; 2861 ddpa.err_ds = conflsnap; 2862 ddpa.cr = CRED(); 2863 2864 return (dsl_sync_task(name, dsl_dataset_promote_check, 2865 dsl_dataset_promote_sync, &ddpa, 2866 2 + numsnaps, ZFS_SPACE_CHECK_RESERVED)); 2867 } 2868 2869 int 2870 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2871 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2872 { 2873 /* 2874 * "slack" factor for received datasets with refquota set on them. 2875 * See the bottom of this function for details on its use. 2876 */ 2877 uint64_t refquota_slack = DMU_MAX_ACCESS * spa_asize_inflation; 2878 int64_t unused_refres_delta; 2879 2880 /* they should both be heads */ 2881 if (clone->ds_is_snapshot || 2882 origin_head->ds_is_snapshot) 2883 return (SET_ERROR(EINVAL)); 2884 2885 /* if we are not forcing, the branch point should be just before them */ 2886 if (!force && clone->ds_prev != origin_head->ds_prev) 2887 return (SET_ERROR(EINVAL)); 2888 2889 /* clone should be the clone (unless they are unrelated) */ 2890 if (clone->ds_prev != NULL && 2891 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2892 origin_head->ds_dir != clone->ds_prev->ds_dir) 2893 return (SET_ERROR(EINVAL)); 2894 2895 /* the clone should be a child of the origin */ 2896 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2897 return (SET_ERROR(EINVAL)); 2898 2899 /* origin_head shouldn't be modified unless 'force' */ 2900 if (!force && 2901 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2902 return (SET_ERROR(ETXTBSY)); 2903 2904 /* origin_head should have no long holds (e.g. is not mounted) */ 2905 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2906 return (SET_ERROR(EBUSY)); 2907 2908 /* check amount of any unconsumed refreservation */ 2909 unused_refres_delta = 2910 (int64_t)MIN(origin_head->ds_reserved, 2911 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 2912 (int64_t)MIN(origin_head->ds_reserved, 2913 dsl_dataset_phys(clone)->ds_unique_bytes); 2914 2915 if (unused_refres_delta > 0 && 2916 unused_refres_delta > 2917 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2918 return (SET_ERROR(ENOSPC)); 2919 2920 /* 2921 * The clone can't be too much over the head's refquota. 2922 * 2923 * To ensure that the entire refquota can be used, we allow one 2924 * transaction to exceed the the refquota. Therefore, this check 2925 * needs to also allow for the space referenced to be more than the 2926 * refquota. The maximum amount of space that one transaction can use 2927 * on disk is DMU_MAX_ACCESS * spa_asize_inflation. Allowing this 2928 * overage ensures that we are able to receive a filesystem that 2929 * exceeds the refquota on the source system. 2930 * 2931 * So that overage is the refquota_slack we use below. 2932 */ 2933 if (origin_head->ds_quota != 0 && 2934 dsl_dataset_phys(clone)->ds_referenced_bytes > 2935 origin_head->ds_quota + refquota_slack) 2936 return (SET_ERROR(EDQUOT)); 2937 2938 return (0); 2939 } 2940 2941 void 2942 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2943 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2944 { 2945 dsl_pool_t *dp = dmu_tx_pool(tx); 2946 int64_t unused_refres_delta; 2947 2948 ASSERT(clone->ds_reserved == 0); 2949 /* 2950 * NOTE: On DEBUG kernels there could be a race between this and 2951 * the check function if spa_asize_inflation is adjusted... 2952 */ 2953 ASSERT(origin_head->ds_quota == 0 || 2954 dsl_dataset_phys(clone)->ds_unique_bytes <= origin_head->ds_quota + 2955 DMU_MAX_ACCESS * spa_asize_inflation); 2956 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2957 2958 /* 2959 * Swap per-dataset feature flags. 2960 */ 2961 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 2962 if (!(spa_feature_table[f].fi_flags & 2963 ZFEATURE_FLAG_PER_DATASET)) { 2964 ASSERT(!clone->ds_feature_inuse[f]); 2965 ASSERT(!origin_head->ds_feature_inuse[f]); 2966 continue; 2967 } 2968 2969 boolean_t clone_inuse = clone->ds_feature_inuse[f]; 2970 boolean_t origin_head_inuse = origin_head->ds_feature_inuse[f]; 2971 2972 if (clone_inuse) { 2973 dsl_dataset_deactivate_feature(clone->ds_object, f, tx); 2974 clone->ds_feature_inuse[f] = B_FALSE; 2975 } 2976 if (origin_head_inuse) { 2977 dsl_dataset_deactivate_feature(origin_head->ds_object, 2978 f, tx); 2979 origin_head->ds_feature_inuse[f] = B_FALSE; 2980 } 2981 if (clone_inuse) { 2982 dsl_dataset_activate_feature(origin_head->ds_object, 2983 f, tx); 2984 origin_head->ds_feature_inuse[f] = B_TRUE; 2985 } 2986 if (origin_head_inuse) { 2987 dsl_dataset_activate_feature(clone->ds_object, f, tx); 2988 clone->ds_feature_inuse[f] = B_TRUE; 2989 } 2990 } 2991 2992 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2993 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2994 2995 if (clone->ds_objset != NULL) { 2996 dmu_objset_evict(clone->ds_objset); 2997 clone->ds_objset = NULL; 2998 } 2999 3000 if (origin_head->ds_objset != NULL) { 3001 dmu_objset_evict(origin_head->ds_objset); 3002 origin_head->ds_objset = NULL; 3003 } 3004 3005 unused_refres_delta = 3006 (int64_t)MIN(origin_head->ds_reserved, 3007 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 3008 (int64_t)MIN(origin_head->ds_reserved, 3009 dsl_dataset_phys(clone)->ds_unique_bytes); 3010 3011 /* 3012 * Reset origin's unique bytes, if it exists. 3013 */ 3014 if (clone->ds_prev) { 3015 dsl_dataset_t *origin = clone->ds_prev; 3016 uint64_t comp, uncomp; 3017 3018 dmu_buf_will_dirty(origin->ds_dbuf, tx); 3019 dsl_deadlist_space_range(&clone->ds_deadlist, 3020 dsl_dataset_phys(origin)->ds_prev_snap_txg, UINT64_MAX, 3021 &dsl_dataset_phys(origin)->ds_unique_bytes, &comp, &uncomp); 3022 } 3023 3024 /* swap blkptrs */ 3025 { 3026 rrw_enter(&clone->ds_bp_rwlock, RW_WRITER, FTAG); 3027 rrw_enter(&origin_head->ds_bp_rwlock, RW_WRITER, FTAG); 3028 blkptr_t tmp; 3029 tmp = dsl_dataset_phys(origin_head)->ds_bp; 3030 dsl_dataset_phys(origin_head)->ds_bp = 3031 dsl_dataset_phys(clone)->ds_bp; 3032 dsl_dataset_phys(clone)->ds_bp = tmp; 3033 rrw_exit(&origin_head->ds_bp_rwlock, FTAG); 3034 rrw_exit(&clone->ds_bp_rwlock, FTAG); 3035 } 3036 3037 /* set dd_*_bytes */ 3038 { 3039 int64_t dused, dcomp, duncomp; 3040 uint64_t cdl_used, cdl_comp, cdl_uncomp; 3041 uint64_t odl_used, odl_comp, odl_uncomp; 3042 3043 ASSERT3U(dsl_dir_phys(clone->ds_dir)-> 3044 dd_used_breakdown[DD_USED_SNAP], ==, 0); 3045 3046 dsl_deadlist_space(&clone->ds_deadlist, 3047 &cdl_used, &cdl_comp, &cdl_uncomp); 3048 dsl_deadlist_space(&origin_head->ds_deadlist, 3049 &odl_used, &odl_comp, &odl_uncomp); 3050 3051 dused = dsl_dataset_phys(clone)->ds_referenced_bytes + 3052 cdl_used - 3053 (dsl_dataset_phys(origin_head)->ds_referenced_bytes + 3054 odl_used); 3055 dcomp = dsl_dataset_phys(clone)->ds_compressed_bytes + 3056 cdl_comp - 3057 (dsl_dataset_phys(origin_head)->ds_compressed_bytes + 3058 odl_comp); 3059 duncomp = dsl_dataset_phys(clone)->ds_uncompressed_bytes + 3060 cdl_uncomp - 3061 (dsl_dataset_phys(origin_head)->ds_uncompressed_bytes + 3062 odl_uncomp); 3063 3064 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 3065 dused, dcomp, duncomp, tx); 3066 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 3067 -dused, -dcomp, -duncomp, tx); 3068 3069 /* 3070 * The difference in the space used by snapshots is the 3071 * difference in snapshot space due to the head's 3072 * deadlist (since that's the only thing that's 3073 * changing that affects the snapused). 3074 */ 3075 dsl_deadlist_space_range(&clone->ds_deadlist, 3076 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3077 &cdl_used, &cdl_comp, &cdl_uncomp); 3078 dsl_deadlist_space_range(&origin_head->ds_deadlist, 3079 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3080 &odl_used, &odl_comp, &odl_uncomp); 3081 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 3082 DD_USED_HEAD, DD_USED_SNAP, tx); 3083 } 3084 3085 /* swap ds_*_bytes */ 3086 SWITCH64(dsl_dataset_phys(origin_head)->ds_referenced_bytes, 3087 dsl_dataset_phys(clone)->ds_referenced_bytes); 3088 SWITCH64(dsl_dataset_phys(origin_head)->ds_compressed_bytes, 3089 dsl_dataset_phys(clone)->ds_compressed_bytes); 3090 SWITCH64(dsl_dataset_phys(origin_head)->ds_uncompressed_bytes, 3091 dsl_dataset_phys(clone)->ds_uncompressed_bytes); 3092 SWITCH64(dsl_dataset_phys(origin_head)->ds_unique_bytes, 3093 dsl_dataset_phys(clone)->ds_unique_bytes); 3094 3095 /* apply any parent delta for change in unconsumed refreservation */ 3096 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 3097 unused_refres_delta, 0, 0, tx); 3098 3099 /* 3100 * Swap deadlists. 3101 */ 3102 dsl_deadlist_close(&clone->ds_deadlist); 3103 dsl_deadlist_close(&origin_head->ds_deadlist); 3104 SWITCH64(dsl_dataset_phys(origin_head)->ds_deadlist_obj, 3105 dsl_dataset_phys(clone)->ds_deadlist_obj); 3106 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 3107 dsl_dataset_phys(clone)->ds_deadlist_obj); 3108 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 3109 dsl_dataset_phys(origin_head)->ds_deadlist_obj); 3110 3111 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 3112 3113 spa_history_log_internal_ds(clone, "clone swap", tx, 3114 "parent=%s", origin_head->ds_dir->dd_myname); 3115 } 3116 3117 /* 3118 * Given a pool name and a dataset object number in that pool, 3119 * return the name of that dataset. 3120 */ 3121 int 3122 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 3123 { 3124 dsl_pool_t *dp; 3125 dsl_dataset_t *ds; 3126 int error; 3127 3128 error = dsl_pool_hold(pname, FTAG, &dp); 3129 if (error != 0) 3130 return (error); 3131 3132 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 3133 if (error == 0) { 3134 dsl_dataset_name(ds, buf); 3135 dsl_dataset_rele(ds, FTAG); 3136 } 3137 dsl_pool_rele(dp, FTAG); 3138 3139 return (error); 3140 } 3141 3142 int 3143 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 3144 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 3145 { 3146 int error = 0; 3147 3148 ASSERT3S(asize, >, 0); 3149 3150 /* 3151 * *ref_rsrv is the portion of asize that will come from any 3152 * unconsumed refreservation space. 3153 */ 3154 *ref_rsrv = 0; 3155 3156 mutex_enter(&ds->ds_lock); 3157 /* 3158 * Make a space adjustment for reserved bytes. 3159 */ 3160 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) { 3161 ASSERT3U(*used, >=, 3162 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3163 *used -= 3164 (ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3165 *ref_rsrv = 3166 asize - MIN(asize, parent_delta(ds, asize + inflight)); 3167 } 3168 3169 if (!check_quota || ds->ds_quota == 0) { 3170 mutex_exit(&ds->ds_lock); 3171 return (0); 3172 } 3173 /* 3174 * If they are requesting more space, and our current estimate 3175 * is over quota, they get to try again unless the actual 3176 * on-disk is over quota and there are no pending changes (which 3177 * may free up space for us). 3178 */ 3179 if (dsl_dataset_phys(ds)->ds_referenced_bytes + inflight >= 3180 ds->ds_quota) { 3181 if (inflight > 0 || 3182 dsl_dataset_phys(ds)->ds_referenced_bytes < ds->ds_quota) 3183 error = SET_ERROR(ERESTART); 3184 else 3185 error = SET_ERROR(EDQUOT); 3186 } 3187 mutex_exit(&ds->ds_lock); 3188 3189 return (error); 3190 } 3191 3192 typedef struct dsl_dataset_set_qr_arg { 3193 const char *ddsqra_name; 3194 zprop_source_t ddsqra_source; 3195 uint64_t ddsqra_value; 3196 } dsl_dataset_set_qr_arg_t; 3197 3198 3199 /* ARGSUSED */ 3200 static int 3201 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 3202 { 3203 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3204 dsl_pool_t *dp = dmu_tx_pool(tx); 3205 dsl_dataset_t *ds; 3206 int error; 3207 uint64_t newval; 3208 3209 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 3210 return (SET_ERROR(ENOTSUP)); 3211 3212 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3213 if (error != 0) 3214 return (error); 3215 3216 if (ds->ds_is_snapshot) { 3217 dsl_dataset_rele(ds, FTAG); 3218 return (SET_ERROR(EINVAL)); 3219 } 3220 3221 error = dsl_prop_predict(ds->ds_dir, 3222 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3223 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3224 if (error != 0) { 3225 dsl_dataset_rele(ds, FTAG); 3226 return (error); 3227 } 3228 3229 if (newval == 0) { 3230 dsl_dataset_rele(ds, FTAG); 3231 return (0); 3232 } 3233 3234 if (newval < dsl_dataset_phys(ds)->ds_referenced_bytes || 3235 newval < ds->ds_reserved) { 3236 dsl_dataset_rele(ds, FTAG); 3237 return (SET_ERROR(ENOSPC)); 3238 } 3239 3240 dsl_dataset_rele(ds, FTAG); 3241 return (0); 3242 } 3243 3244 static void 3245 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 3246 { 3247 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3248 dsl_pool_t *dp = dmu_tx_pool(tx); 3249 dsl_dataset_t *ds; 3250 uint64_t newval; 3251 3252 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3253 3254 dsl_prop_set_sync_impl(ds, 3255 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3256 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 3257 &ddsqra->ddsqra_value, tx); 3258 3259 VERIFY0(dsl_prop_get_int_ds(ds, 3260 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 3261 3262 if (ds->ds_quota != newval) { 3263 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3264 ds->ds_quota = newval; 3265 } 3266 dsl_dataset_rele(ds, FTAG); 3267 } 3268 3269 int 3270 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 3271 uint64_t refquota) 3272 { 3273 dsl_dataset_set_qr_arg_t ddsqra; 3274 3275 ddsqra.ddsqra_name = dsname; 3276 ddsqra.ddsqra_source = source; 3277 ddsqra.ddsqra_value = refquota; 3278 3279 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 3280 dsl_dataset_set_refquota_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE)); 3281 } 3282 3283 static int 3284 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 3285 { 3286 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3287 dsl_pool_t *dp = dmu_tx_pool(tx); 3288 dsl_dataset_t *ds; 3289 int error; 3290 uint64_t newval, unique; 3291 3292 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 3293 return (SET_ERROR(ENOTSUP)); 3294 3295 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3296 if (error != 0) 3297 return (error); 3298 3299 if (ds->ds_is_snapshot) { 3300 dsl_dataset_rele(ds, FTAG); 3301 return (SET_ERROR(EINVAL)); 3302 } 3303 3304 error = dsl_prop_predict(ds->ds_dir, 3305 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3306 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3307 if (error != 0) { 3308 dsl_dataset_rele(ds, FTAG); 3309 return (error); 3310 } 3311 3312 /* 3313 * If we are doing the preliminary check in open context, the 3314 * space estimates may be inaccurate. 3315 */ 3316 if (!dmu_tx_is_syncing(tx)) { 3317 dsl_dataset_rele(ds, FTAG); 3318 return (0); 3319 } 3320 3321 mutex_enter(&ds->ds_lock); 3322 if (!DS_UNIQUE_IS_ACCURATE(ds)) 3323 dsl_dataset_recalc_head_uniq(ds); 3324 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3325 mutex_exit(&ds->ds_lock); 3326 3327 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 3328 uint64_t delta = MAX(unique, newval) - 3329 MAX(unique, ds->ds_reserved); 3330 3331 if (delta > 3332 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 3333 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 3334 dsl_dataset_rele(ds, FTAG); 3335 return (SET_ERROR(ENOSPC)); 3336 } 3337 } 3338 3339 dsl_dataset_rele(ds, FTAG); 3340 return (0); 3341 } 3342 3343 void 3344 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 3345 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 3346 { 3347 uint64_t newval; 3348 uint64_t unique; 3349 int64_t delta; 3350 3351 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3352 source, sizeof (value), 1, &value, tx); 3353 3354 VERIFY0(dsl_prop_get_int_ds(ds, 3355 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 3356 3357 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3358 mutex_enter(&ds->ds_dir->dd_lock); 3359 mutex_enter(&ds->ds_lock); 3360 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 3361 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3362 delta = MAX(0, (int64_t)(newval - unique)) - 3363 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3364 ds->ds_reserved = newval; 3365 mutex_exit(&ds->ds_lock); 3366 3367 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3368 mutex_exit(&ds->ds_dir->dd_lock); 3369 } 3370 3371 static void 3372 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 3373 { 3374 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3375 dsl_pool_t *dp = dmu_tx_pool(tx); 3376 dsl_dataset_t *ds; 3377 3378 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3379 dsl_dataset_set_refreservation_sync_impl(ds, 3380 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 3381 dsl_dataset_rele(ds, FTAG); 3382 } 3383 3384 int 3385 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 3386 uint64_t refreservation) 3387 { 3388 dsl_dataset_set_qr_arg_t ddsqra; 3389 3390 ddsqra.ddsqra_name = dsname; 3391 ddsqra.ddsqra_source = source; 3392 ddsqra.ddsqra_value = refreservation; 3393 3394 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 3395 dsl_dataset_set_refreservation_sync, &ddsqra, 3396 0, ZFS_SPACE_CHECK_NONE)); 3397 } 3398 3399 /* 3400 * Return (in *usedp) the amount of space written in new that is not 3401 * present in oldsnap. New may be a snapshot or the head. Old must be 3402 * a snapshot before new, in new's filesystem (or its origin). If not then 3403 * fail and return EINVAL. 3404 * 3405 * The written space is calculated by considering two components: First, we 3406 * ignore any freed space, and calculate the written as new's used space 3407 * minus old's used space. Next, we add in the amount of space that was freed 3408 * between the two snapshots, thus reducing new's used space relative to old's. 3409 * Specifically, this is the space that was born before old->ds_creation_txg, 3410 * and freed before new (ie. on new's deadlist or a previous deadlist). 3411 * 3412 * space freed [---------------------] 3413 * snapshots ---O-------O--------O-------O------ 3414 * oldsnap new 3415 */ 3416 int 3417 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 3418 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3419 { 3420 int err = 0; 3421 uint64_t snapobj; 3422 dsl_pool_t *dp = new->ds_dir->dd_pool; 3423 3424 ASSERT(dsl_pool_config_held(dp)); 3425 3426 *usedp = 0; 3427 *usedp += dsl_dataset_phys(new)->ds_referenced_bytes; 3428 *usedp -= dsl_dataset_phys(oldsnap)->ds_referenced_bytes; 3429 3430 *compp = 0; 3431 *compp += dsl_dataset_phys(new)->ds_compressed_bytes; 3432 *compp -= dsl_dataset_phys(oldsnap)->ds_compressed_bytes; 3433 3434 *uncompp = 0; 3435 *uncompp += dsl_dataset_phys(new)->ds_uncompressed_bytes; 3436 *uncompp -= dsl_dataset_phys(oldsnap)->ds_uncompressed_bytes; 3437 3438 snapobj = new->ds_object; 3439 while (snapobj != oldsnap->ds_object) { 3440 dsl_dataset_t *snap; 3441 uint64_t used, comp, uncomp; 3442 3443 if (snapobj == new->ds_object) { 3444 snap = new; 3445 } else { 3446 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 3447 if (err != 0) 3448 break; 3449 } 3450 3451 if (dsl_dataset_phys(snap)->ds_prev_snap_txg == 3452 dsl_dataset_phys(oldsnap)->ds_creation_txg) { 3453 /* 3454 * The blocks in the deadlist can not be born after 3455 * ds_prev_snap_txg, so get the whole deadlist space, 3456 * which is more efficient (especially for old-format 3457 * deadlists). Unfortunately the deadlist code 3458 * doesn't have enough information to make this 3459 * optimization itself. 3460 */ 3461 dsl_deadlist_space(&snap->ds_deadlist, 3462 &used, &comp, &uncomp); 3463 } else { 3464 dsl_deadlist_space_range(&snap->ds_deadlist, 3465 0, dsl_dataset_phys(oldsnap)->ds_creation_txg, 3466 &used, &comp, &uncomp); 3467 } 3468 *usedp += used; 3469 *compp += comp; 3470 *uncompp += uncomp; 3471 3472 /* 3473 * If we get to the beginning of the chain of snapshots 3474 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 3475 * was not a snapshot of/before new. 3476 */ 3477 snapobj = dsl_dataset_phys(snap)->ds_prev_snap_obj; 3478 if (snap != new) 3479 dsl_dataset_rele(snap, FTAG); 3480 if (snapobj == 0) { 3481 err = SET_ERROR(EINVAL); 3482 break; 3483 } 3484 3485 } 3486 return (err); 3487 } 3488 3489 /* 3490 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 3491 * lastsnap, and all snapshots in between are deleted. 3492 * 3493 * blocks that would be freed [---------------------------] 3494 * snapshots ---O-------O--------O-------O--------O 3495 * firstsnap lastsnap 3496 * 3497 * This is the set of blocks that were born after the snap before firstsnap, 3498 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 3499 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 3500 * We calculate this by iterating over the relevant deadlists (from the snap 3501 * after lastsnap, backward to the snap after firstsnap), summing up the 3502 * space on the deadlist that was born after the snap before firstsnap. 3503 */ 3504 int 3505 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 3506 dsl_dataset_t *lastsnap, 3507 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3508 { 3509 int err = 0; 3510 uint64_t snapobj; 3511 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 3512 3513 ASSERT(firstsnap->ds_is_snapshot); 3514 ASSERT(lastsnap->ds_is_snapshot); 3515 3516 /* 3517 * Check that the snapshots are in the same dsl_dir, and firstsnap 3518 * is before lastsnap. 3519 */ 3520 if (firstsnap->ds_dir != lastsnap->ds_dir || 3521 dsl_dataset_phys(firstsnap)->ds_creation_txg > 3522 dsl_dataset_phys(lastsnap)->ds_creation_txg) 3523 return (SET_ERROR(EINVAL)); 3524 3525 *usedp = *compp = *uncompp = 0; 3526 3527 snapobj = dsl_dataset_phys(lastsnap)->ds_next_snap_obj; 3528 while (snapobj != firstsnap->ds_object) { 3529 dsl_dataset_t *ds; 3530 uint64_t used, comp, uncomp; 3531 3532 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 3533 if (err != 0) 3534 break; 3535 3536 dsl_deadlist_space_range(&ds->ds_deadlist, 3537 dsl_dataset_phys(firstsnap)->ds_prev_snap_txg, UINT64_MAX, 3538 &used, &comp, &uncomp); 3539 *usedp += used; 3540 *compp += comp; 3541 *uncompp += uncomp; 3542 3543 snapobj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 3544 ASSERT3U(snapobj, !=, 0); 3545 dsl_dataset_rele(ds, FTAG); 3546 } 3547 return (err); 3548 } 3549 3550 /* 3551 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 3552 * For example, they could both be snapshots of the same filesystem, and 3553 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 3554 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 3555 * filesystem. Or 'earlier' could be the origin's origin. 3556 * 3557 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg. 3558 */ 3559 boolean_t 3560 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier, 3561 uint64_t earlier_txg) 3562 { 3563 dsl_pool_t *dp = later->ds_dir->dd_pool; 3564 int error; 3565 boolean_t ret; 3566 3567 ASSERT(dsl_pool_config_held(dp)); 3568 ASSERT(earlier->ds_is_snapshot || earlier_txg != 0); 3569 3570 if (earlier_txg == 0) 3571 earlier_txg = dsl_dataset_phys(earlier)->ds_creation_txg; 3572 3573 if (later->ds_is_snapshot && 3574 earlier_txg >= dsl_dataset_phys(later)->ds_creation_txg) 3575 return (B_FALSE); 3576 3577 if (later->ds_dir == earlier->ds_dir) 3578 return (B_TRUE); 3579 if (!dsl_dir_is_clone(later->ds_dir)) 3580 return (B_FALSE); 3581 3582 if (dsl_dir_phys(later->ds_dir)->dd_origin_obj == earlier->ds_object) 3583 return (B_TRUE); 3584 dsl_dataset_t *origin; 3585 error = dsl_dataset_hold_obj(dp, 3586 dsl_dir_phys(later->ds_dir)->dd_origin_obj, FTAG, &origin); 3587 if (error != 0) 3588 return (B_FALSE); 3589 ret = dsl_dataset_is_before(origin, earlier, earlier_txg); 3590 dsl_dataset_rele(origin, FTAG); 3591 return (ret); 3592 } 3593 3594 void 3595 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx) 3596 { 3597 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 3598 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx); 3599 } 3600 3601 boolean_t 3602 dsl_dataset_is_zapified(dsl_dataset_t *ds) 3603 { 3604 dmu_object_info_t doi; 3605 3606 dmu_object_info_from_db(ds->ds_dbuf, &doi); 3607 return (doi.doi_type == DMU_OTN_ZAP_METADATA); 3608 } 3609 3610 boolean_t 3611 dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds) 3612 { 3613 return (dsl_dataset_is_zapified(ds) && 3614 zap_contains(ds->ds_dir->dd_pool->dp_meta_objset, 3615 ds->ds_object, DS_FIELD_RESUME_TOGUID) == 0); 3616 } 3617