1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2015 by Delphix. All rights reserved. 24 * Copyright (c) 2014, Joyent, Inc. All rights reserved. 25 * Copyright (c) 2014 RackTop Systems. 26 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 27 * Copyright (c) 2014 Integros [integros.com] 28 * Copyright 2016, OmniTI Computer Consulting, Inc. All rights reserved. 29 */ 30 31 #include <sys/dmu_objset.h> 32 #include <sys/dsl_dataset.h> 33 #include <sys/dsl_dir.h> 34 #include <sys/dsl_prop.h> 35 #include <sys/dsl_synctask.h> 36 #include <sys/dmu_traverse.h> 37 #include <sys/dmu_impl.h> 38 #include <sys/dmu_tx.h> 39 #include <sys/arc.h> 40 #include <sys/zio.h> 41 #include <sys/zap.h> 42 #include <sys/zfeature.h> 43 #include <sys/unique.h> 44 #include <sys/zfs_context.h> 45 #include <sys/zfs_ioctl.h> 46 #include <sys/spa.h> 47 #include <sys/zfs_znode.h> 48 #include <sys/zfs_onexit.h> 49 #include <sys/zvol.h> 50 #include <sys/dsl_scan.h> 51 #include <sys/dsl_deadlist.h> 52 #include <sys/dsl_destroy.h> 53 #include <sys/dsl_userhold.h> 54 #include <sys/dsl_bookmark.h> 55 #include <sys/dmu_send.h> 56 #include <sys/zio_checksum.h> 57 #include <sys/zio_compress.h> 58 #include <zfs_fletcher.h> 59 60 /* 61 * The SPA supports block sizes up to 16MB. However, very large blocks 62 * can have an impact on i/o latency (e.g. tying up a spinning disk for 63 * ~300ms), and also potentially on the memory allocator. Therefore, 64 * we do not allow the recordsize to be set larger than zfs_max_recordsize 65 * (default 1MB). Larger blocks can be created by changing this tunable, 66 * and pools with larger blocks can always be imported and used, regardless 67 * of this setting. 68 */ 69 int zfs_max_recordsize = 1 * 1024 * 1024; 70 71 #define SWITCH64(x, y) \ 72 { \ 73 uint64_t __tmp = (x); \ 74 (x) = (y); \ 75 (y) = __tmp; \ 76 } 77 78 #define DS_REF_MAX (1ULL << 62) 79 80 extern inline dsl_dataset_phys_t *dsl_dataset_phys(dsl_dataset_t *ds); 81 82 extern int spa_asize_inflation; 83 84 /* 85 * Figure out how much of this delta should be propogated to the dsl_dir 86 * layer. If there's a refreservation, that space has already been 87 * partially accounted for in our ancestors. 88 */ 89 static int64_t 90 parent_delta(dsl_dataset_t *ds, int64_t delta) 91 { 92 dsl_dataset_phys_t *ds_phys; 93 uint64_t old_bytes, new_bytes; 94 95 if (ds->ds_reserved == 0) 96 return (delta); 97 98 ds_phys = dsl_dataset_phys(ds); 99 old_bytes = MAX(ds_phys->ds_unique_bytes, ds->ds_reserved); 100 new_bytes = MAX(ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 101 102 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 103 return (new_bytes - old_bytes); 104 } 105 106 void 107 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 108 { 109 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 110 int compressed = BP_GET_PSIZE(bp); 111 int uncompressed = BP_GET_UCSIZE(bp); 112 int64_t delta; 113 114 dprintf_bp(bp, "ds=%p", ds); 115 116 ASSERT(dmu_tx_is_syncing(tx)); 117 /* It could have been compressed away to nothing */ 118 if (BP_IS_HOLE(bp)) 119 return; 120 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 121 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 122 if (ds == NULL) { 123 dsl_pool_mos_diduse_space(tx->tx_pool, 124 used, compressed, uncompressed); 125 return; 126 } 127 128 dmu_buf_will_dirty(ds->ds_dbuf, tx); 129 mutex_enter(&ds->ds_lock); 130 delta = parent_delta(ds, used); 131 dsl_dataset_phys(ds)->ds_referenced_bytes += used; 132 dsl_dataset_phys(ds)->ds_compressed_bytes += compressed; 133 dsl_dataset_phys(ds)->ds_uncompressed_bytes += uncompressed; 134 dsl_dataset_phys(ds)->ds_unique_bytes += used; 135 136 if (BP_GET_LSIZE(bp) > SPA_OLD_MAXBLOCKSIZE) { 137 ds->ds_feature_activation_needed[SPA_FEATURE_LARGE_BLOCKS] = 138 B_TRUE; 139 } 140 141 spa_feature_t f = zio_checksum_to_feature(BP_GET_CHECKSUM(bp)); 142 if (f != SPA_FEATURE_NONE) 143 ds->ds_feature_activation_needed[f] = B_TRUE; 144 145 mutex_exit(&ds->ds_lock); 146 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 147 compressed, uncompressed, tx); 148 dsl_dir_transfer_space(ds->ds_dir, used - delta, 149 DD_USED_REFRSRV, DD_USED_HEAD, tx); 150 } 151 152 int 153 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 154 boolean_t async) 155 { 156 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 157 int compressed = BP_GET_PSIZE(bp); 158 int uncompressed = BP_GET_UCSIZE(bp); 159 160 if (BP_IS_HOLE(bp)) 161 return (0); 162 163 ASSERT(dmu_tx_is_syncing(tx)); 164 ASSERT(bp->blk_birth <= tx->tx_txg); 165 166 if (ds == NULL) { 167 dsl_free(tx->tx_pool, tx->tx_txg, bp); 168 dsl_pool_mos_diduse_space(tx->tx_pool, 169 -used, -compressed, -uncompressed); 170 return (used); 171 } 172 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 173 174 ASSERT(!ds->ds_is_snapshot); 175 dmu_buf_will_dirty(ds->ds_dbuf, tx); 176 177 if (bp->blk_birth > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 178 int64_t delta; 179 180 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 181 dsl_free(tx->tx_pool, tx->tx_txg, bp); 182 183 mutex_enter(&ds->ds_lock); 184 ASSERT(dsl_dataset_phys(ds)->ds_unique_bytes >= used || 185 !DS_UNIQUE_IS_ACCURATE(ds)); 186 delta = parent_delta(ds, -used); 187 dsl_dataset_phys(ds)->ds_unique_bytes -= used; 188 mutex_exit(&ds->ds_lock); 189 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 190 delta, -compressed, -uncompressed, tx); 191 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 192 DD_USED_REFRSRV, DD_USED_HEAD, tx); 193 } else { 194 dprintf_bp(bp, "putting on dead list: %s", ""); 195 if (async) { 196 /* 197 * We are here as part of zio's write done callback, 198 * which means we're a zio interrupt thread. We can't 199 * call dsl_deadlist_insert() now because it may block 200 * waiting for I/O. Instead, put bp on the deferred 201 * queue and let dsl_pool_sync() finish the job. 202 */ 203 bplist_append(&ds->ds_pending_deadlist, bp); 204 } else { 205 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 206 } 207 ASSERT3U(ds->ds_prev->ds_object, ==, 208 dsl_dataset_phys(ds)->ds_prev_snap_obj); 209 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_num_children > 0); 210 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 211 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 212 ds->ds_object && bp->blk_birth > 213 dsl_dataset_phys(ds->ds_prev)->ds_prev_snap_txg) { 214 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 215 mutex_enter(&ds->ds_prev->ds_lock); 216 dsl_dataset_phys(ds->ds_prev)->ds_unique_bytes += used; 217 mutex_exit(&ds->ds_prev->ds_lock); 218 } 219 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 220 dsl_dir_transfer_space(ds->ds_dir, used, 221 DD_USED_HEAD, DD_USED_SNAP, tx); 222 } 223 } 224 mutex_enter(&ds->ds_lock); 225 ASSERT3U(dsl_dataset_phys(ds)->ds_referenced_bytes, >=, used); 226 dsl_dataset_phys(ds)->ds_referenced_bytes -= used; 227 ASSERT3U(dsl_dataset_phys(ds)->ds_compressed_bytes, >=, compressed); 228 dsl_dataset_phys(ds)->ds_compressed_bytes -= compressed; 229 ASSERT3U(dsl_dataset_phys(ds)->ds_uncompressed_bytes, >=, uncompressed); 230 dsl_dataset_phys(ds)->ds_uncompressed_bytes -= uncompressed; 231 mutex_exit(&ds->ds_lock); 232 233 return (used); 234 } 235 236 uint64_t 237 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 238 { 239 uint64_t trysnap = 0; 240 241 if (ds == NULL) 242 return (0); 243 /* 244 * The snapshot creation could fail, but that would cause an 245 * incorrect FALSE return, which would only result in an 246 * overestimation of the amount of space that an operation would 247 * consume, which is OK. 248 * 249 * There's also a small window where we could miss a pending 250 * snapshot, because we could set the sync task in the quiescing 251 * phase. So this should only be used as a guess. 252 */ 253 if (ds->ds_trysnap_txg > 254 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 255 trysnap = ds->ds_trysnap_txg; 256 return (MAX(dsl_dataset_phys(ds)->ds_prev_snap_txg, trysnap)); 257 } 258 259 boolean_t 260 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp, 261 uint64_t blk_birth) 262 { 263 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) || 264 (bp != NULL && BP_IS_HOLE(bp))) 265 return (B_FALSE); 266 267 ddt_prefetch(dsl_dataset_get_spa(ds), bp); 268 269 return (B_TRUE); 270 } 271 272 static void 273 dsl_dataset_evict(void *dbu) 274 { 275 dsl_dataset_t *ds = dbu; 276 277 ASSERT(ds->ds_owner == NULL); 278 279 ds->ds_dbuf = NULL; 280 281 unique_remove(ds->ds_fsid_guid); 282 283 if (ds->ds_objset != NULL) 284 dmu_objset_evict(ds->ds_objset); 285 286 if (ds->ds_prev) { 287 dsl_dataset_rele(ds->ds_prev, ds); 288 ds->ds_prev = NULL; 289 } 290 291 bplist_destroy(&ds->ds_pending_deadlist); 292 if (ds->ds_deadlist.dl_os != NULL) 293 dsl_deadlist_close(&ds->ds_deadlist); 294 if (ds->ds_dir) 295 dsl_dir_async_rele(ds->ds_dir, ds); 296 297 ASSERT(!list_link_active(&ds->ds_synced_link)); 298 299 list_destroy(&ds->ds_prop_cbs); 300 mutex_destroy(&ds->ds_lock); 301 mutex_destroy(&ds->ds_opening_lock); 302 mutex_destroy(&ds->ds_sendstream_lock); 303 refcount_destroy(&ds->ds_longholds); 304 305 kmem_free(ds, sizeof (dsl_dataset_t)); 306 } 307 308 int 309 dsl_dataset_get_snapname(dsl_dataset_t *ds) 310 { 311 dsl_dataset_phys_t *headphys; 312 int err; 313 dmu_buf_t *headdbuf; 314 dsl_pool_t *dp = ds->ds_dir->dd_pool; 315 objset_t *mos = dp->dp_meta_objset; 316 317 if (ds->ds_snapname[0]) 318 return (0); 319 if (dsl_dataset_phys(ds)->ds_next_snap_obj == 0) 320 return (0); 321 322 err = dmu_bonus_hold(mos, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, 323 FTAG, &headdbuf); 324 if (err != 0) 325 return (err); 326 headphys = headdbuf->db_data; 327 err = zap_value_search(dp->dp_meta_objset, 328 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 329 dmu_buf_rele(headdbuf, FTAG); 330 return (err); 331 } 332 333 int 334 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 335 { 336 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 337 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 338 matchtype_t mt; 339 int err; 340 341 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 342 mt = MT_FIRST; 343 else 344 mt = MT_EXACT; 345 346 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 347 value, mt, NULL, 0, NULL); 348 if (err == ENOTSUP && mt == MT_FIRST) 349 err = zap_lookup(mos, snapobj, name, 8, 1, value); 350 return (err); 351 } 352 353 int 354 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx, 355 boolean_t adj_cnt) 356 { 357 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 358 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 359 matchtype_t mt; 360 int err; 361 362 dsl_dir_snap_cmtime_update(ds->ds_dir); 363 364 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 365 mt = MT_FIRST; 366 else 367 mt = MT_EXACT; 368 369 err = zap_remove_norm(mos, snapobj, name, mt, tx); 370 if (err == ENOTSUP && mt == MT_FIRST) 371 err = zap_remove(mos, snapobj, name, tx); 372 373 if (err == 0 && adj_cnt) 374 dsl_fs_ss_count_adjust(ds->ds_dir, -1, 375 DD_FIELD_SNAPSHOT_COUNT, tx); 376 377 return (err); 378 } 379 380 boolean_t 381 dsl_dataset_try_add_ref(dsl_pool_t *dp, dsl_dataset_t *ds, void *tag) 382 { 383 dmu_buf_t *dbuf = ds->ds_dbuf; 384 boolean_t result = B_FALSE; 385 386 if (dbuf != NULL && dmu_buf_try_add_ref(dbuf, dp->dp_meta_objset, 387 ds->ds_object, DMU_BONUS_BLKID, tag)) { 388 389 if (ds == dmu_buf_get_user(dbuf)) 390 result = B_TRUE; 391 else 392 dmu_buf_rele(dbuf, tag); 393 } 394 395 return (result); 396 } 397 398 int 399 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 400 dsl_dataset_t **dsp) 401 { 402 objset_t *mos = dp->dp_meta_objset; 403 dmu_buf_t *dbuf; 404 dsl_dataset_t *ds; 405 int err; 406 dmu_object_info_t doi; 407 408 ASSERT(dsl_pool_config_held(dp)); 409 410 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 411 if (err != 0) 412 return (err); 413 414 /* Make sure dsobj has the correct object type. */ 415 dmu_object_info_from_db(dbuf, &doi); 416 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) { 417 dmu_buf_rele(dbuf, tag); 418 return (SET_ERROR(EINVAL)); 419 } 420 421 ds = dmu_buf_get_user(dbuf); 422 if (ds == NULL) { 423 dsl_dataset_t *winner = NULL; 424 425 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 426 ds->ds_dbuf = dbuf; 427 ds->ds_object = dsobj; 428 ds->ds_is_snapshot = dsl_dataset_phys(ds)->ds_num_children != 0; 429 430 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 431 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 432 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 433 refcount_create(&ds->ds_longholds); 434 435 bplist_create(&ds->ds_pending_deadlist); 436 dsl_deadlist_open(&ds->ds_deadlist, 437 mos, dsl_dataset_phys(ds)->ds_deadlist_obj); 438 439 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 440 offsetof(dmu_sendarg_t, dsa_link)); 441 442 list_create(&ds->ds_prop_cbs, sizeof (dsl_prop_cb_record_t), 443 offsetof(dsl_prop_cb_record_t, cbr_ds_node)); 444 445 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 446 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 447 if (!(spa_feature_table[f].fi_flags & 448 ZFEATURE_FLAG_PER_DATASET)) 449 continue; 450 err = zap_contains(mos, dsobj, 451 spa_feature_table[f].fi_guid); 452 if (err == 0) { 453 ds->ds_feature_inuse[f] = B_TRUE; 454 } else { 455 ASSERT3U(err, ==, ENOENT); 456 err = 0; 457 } 458 } 459 } 460 461 err = dsl_dir_hold_obj(dp, 462 dsl_dataset_phys(ds)->ds_dir_obj, NULL, ds, &ds->ds_dir); 463 if (err != 0) { 464 mutex_destroy(&ds->ds_lock); 465 mutex_destroy(&ds->ds_opening_lock); 466 mutex_destroy(&ds->ds_sendstream_lock); 467 refcount_destroy(&ds->ds_longholds); 468 bplist_destroy(&ds->ds_pending_deadlist); 469 dsl_deadlist_close(&ds->ds_deadlist); 470 kmem_free(ds, sizeof (dsl_dataset_t)); 471 dmu_buf_rele(dbuf, tag); 472 return (err); 473 } 474 475 if (!ds->ds_is_snapshot) { 476 ds->ds_snapname[0] = '\0'; 477 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 478 err = dsl_dataset_hold_obj(dp, 479 dsl_dataset_phys(ds)->ds_prev_snap_obj, 480 ds, &ds->ds_prev); 481 } 482 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 483 int zaperr = zap_lookup(mos, ds->ds_object, 484 DS_FIELD_BOOKMARK_NAMES, 485 sizeof (ds->ds_bookmarks), 1, 486 &ds->ds_bookmarks); 487 if (zaperr != ENOENT) 488 VERIFY0(zaperr); 489 } 490 } else { 491 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 492 err = dsl_dataset_get_snapname(ds); 493 if (err == 0 && 494 dsl_dataset_phys(ds)->ds_userrefs_obj != 0) { 495 err = zap_count( 496 ds->ds_dir->dd_pool->dp_meta_objset, 497 dsl_dataset_phys(ds)->ds_userrefs_obj, 498 &ds->ds_userrefs); 499 } 500 } 501 502 if (err == 0 && !ds->ds_is_snapshot) { 503 err = dsl_prop_get_int_ds(ds, 504 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 505 &ds->ds_reserved); 506 if (err == 0) { 507 err = dsl_prop_get_int_ds(ds, 508 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 509 &ds->ds_quota); 510 } 511 } else { 512 ds->ds_reserved = ds->ds_quota = 0; 513 } 514 515 dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict, &ds->ds_dbuf); 516 if (err == 0) 517 winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu); 518 519 if (err != 0 || winner != NULL) { 520 bplist_destroy(&ds->ds_pending_deadlist); 521 dsl_deadlist_close(&ds->ds_deadlist); 522 if (ds->ds_prev) 523 dsl_dataset_rele(ds->ds_prev, ds); 524 dsl_dir_rele(ds->ds_dir, ds); 525 mutex_destroy(&ds->ds_lock); 526 mutex_destroy(&ds->ds_opening_lock); 527 mutex_destroy(&ds->ds_sendstream_lock); 528 refcount_destroy(&ds->ds_longholds); 529 kmem_free(ds, sizeof (dsl_dataset_t)); 530 if (err != 0) { 531 dmu_buf_rele(dbuf, tag); 532 return (err); 533 } 534 ds = winner; 535 } else { 536 ds->ds_fsid_guid = 537 unique_insert(dsl_dataset_phys(ds)->ds_fsid_guid); 538 } 539 } 540 ASSERT3P(ds->ds_dbuf, ==, dbuf); 541 ASSERT3P(dsl_dataset_phys(ds), ==, dbuf->db_data); 542 ASSERT(dsl_dataset_phys(ds)->ds_prev_snap_obj != 0 || 543 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 544 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 545 *dsp = ds; 546 return (0); 547 } 548 549 int 550 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 551 void *tag, dsl_dataset_t **dsp) 552 { 553 dsl_dir_t *dd; 554 const char *snapname; 555 uint64_t obj; 556 int err = 0; 557 dsl_dataset_t *ds; 558 559 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 560 if (err != 0) 561 return (err); 562 563 ASSERT(dsl_pool_config_held(dp)); 564 obj = dsl_dir_phys(dd)->dd_head_dataset_obj; 565 if (obj != 0) 566 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 567 else 568 err = SET_ERROR(ENOENT); 569 570 /* we may be looking for a snapshot */ 571 if (err == 0 && snapname != NULL) { 572 dsl_dataset_t *snap_ds; 573 574 if (*snapname++ != '@') { 575 dsl_dataset_rele(ds, tag); 576 dsl_dir_rele(dd, FTAG); 577 return (SET_ERROR(ENOENT)); 578 } 579 580 dprintf("looking for snapshot '%s'\n", snapname); 581 err = dsl_dataset_snap_lookup(ds, snapname, &obj); 582 if (err == 0) 583 err = dsl_dataset_hold_obj(dp, obj, tag, &snap_ds); 584 dsl_dataset_rele(ds, tag); 585 586 if (err == 0) { 587 mutex_enter(&snap_ds->ds_lock); 588 if (snap_ds->ds_snapname[0] == 0) 589 (void) strlcpy(snap_ds->ds_snapname, snapname, 590 sizeof (snap_ds->ds_snapname)); 591 mutex_exit(&snap_ds->ds_lock); 592 ds = snap_ds; 593 } 594 } 595 if (err == 0) 596 *dsp = ds; 597 dsl_dir_rele(dd, FTAG); 598 return (err); 599 } 600 601 int 602 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 603 void *tag, dsl_dataset_t **dsp) 604 { 605 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 606 if (err != 0) 607 return (err); 608 if (!dsl_dataset_tryown(*dsp, tag)) { 609 dsl_dataset_rele(*dsp, tag); 610 *dsp = NULL; 611 return (SET_ERROR(EBUSY)); 612 } 613 return (0); 614 } 615 616 int 617 dsl_dataset_own(dsl_pool_t *dp, const char *name, 618 void *tag, dsl_dataset_t **dsp) 619 { 620 int err = dsl_dataset_hold(dp, name, tag, dsp); 621 if (err != 0) 622 return (err); 623 if (!dsl_dataset_tryown(*dsp, tag)) { 624 dsl_dataset_rele(*dsp, tag); 625 return (SET_ERROR(EBUSY)); 626 } 627 return (0); 628 } 629 630 /* 631 * See the comment above dsl_pool_hold() for details. In summary, a long 632 * hold is used to prevent destruction of a dataset while the pool hold 633 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 634 * 635 * The dataset and pool must be held when this function is called. After it 636 * is called, the pool hold may be released while the dataset is still held 637 * and accessed. 638 */ 639 void 640 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 641 { 642 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 643 (void) refcount_add(&ds->ds_longholds, tag); 644 } 645 646 void 647 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 648 { 649 (void) refcount_remove(&ds->ds_longholds, tag); 650 } 651 652 /* Return B_TRUE if there are any long holds on this dataset. */ 653 boolean_t 654 dsl_dataset_long_held(dsl_dataset_t *ds) 655 { 656 return (!refcount_is_zero(&ds->ds_longholds)); 657 } 658 659 void 660 dsl_dataset_name(dsl_dataset_t *ds, char *name) 661 { 662 if (ds == NULL) { 663 (void) strcpy(name, "mos"); 664 } else { 665 dsl_dir_name(ds->ds_dir, name); 666 VERIFY0(dsl_dataset_get_snapname(ds)); 667 if (ds->ds_snapname[0]) { 668 (void) strcat(name, "@"); 669 /* 670 * We use a "recursive" mutex so that we 671 * can call dprintf_ds() with ds_lock held. 672 */ 673 if (!MUTEX_HELD(&ds->ds_lock)) { 674 mutex_enter(&ds->ds_lock); 675 VERIFY3U(strlen(name) + 676 strlen(ds->ds_snapname) + 1, <=, 677 ZFS_MAXNAMELEN); 678 (void) strcat(name, ds->ds_snapname); 679 mutex_exit(&ds->ds_lock); 680 } else { 681 VERIFY3U(strlen(name) + 682 strlen(ds->ds_snapname) + 1, <=, 683 ZFS_MAXNAMELEN); 684 (void) strcat(name, ds->ds_snapname); 685 } 686 } 687 } 688 } 689 690 void 691 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 692 { 693 dmu_buf_rele(ds->ds_dbuf, tag); 694 } 695 696 void 697 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 698 { 699 ASSERT3P(ds->ds_owner, ==, tag); 700 ASSERT(ds->ds_dbuf != NULL); 701 702 mutex_enter(&ds->ds_lock); 703 ds->ds_owner = NULL; 704 mutex_exit(&ds->ds_lock); 705 dsl_dataset_long_rele(ds, tag); 706 dsl_dataset_rele(ds, tag); 707 } 708 709 boolean_t 710 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 711 { 712 boolean_t gotit = FALSE; 713 714 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 715 mutex_enter(&ds->ds_lock); 716 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 717 ds->ds_owner = tag; 718 dsl_dataset_long_hold(ds, tag); 719 gotit = TRUE; 720 } 721 mutex_exit(&ds->ds_lock); 722 return (gotit); 723 } 724 725 boolean_t 726 dsl_dataset_has_owner(dsl_dataset_t *ds) 727 { 728 boolean_t rv; 729 mutex_enter(&ds->ds_lock); 730 rv = (ds->ds_owner != NULL); 731 mutex_exit(&ds->ds_lock); 732 return (rv); 733 } 734 735 static void 736 dsl_dataset_activate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 737 { 738 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 739 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 740 uint64_t zero = 0; 741 742 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 743 744 spa_feature_incr(spa, f, tx); 745 dmu_object_zapify(mos, dsobj, DMU_OT_DSL_DATASET, tx); 746 747 VERIFY0(zap_add(mos, dsobj, spa_feature_table[f].fi_guid, 748 sizeof (zero), 1, &zero, tx)); 749 } 750 751 void 752 dsl_dataset_deactivate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 753 { 754 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 755 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 756 757 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 758 759 VERIFY0(zap_remove(mos, dsobj, spa_feature_table[f].fi_guid, tx)); 760 spa_feature_decr(spa, f, tx); 761 } 762 763 uint64_t 764 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 765 uint64_t flags, dmu_tx_t *tx) 766 { 767 dsl_pool_t *dp = dd->dd_pool; 768 dmu_buf_t *dbuf; 769 dsl_dataset_phys_t *dsphys; 770 uint64_t dsobj; 771 objset_t *mos = dp->dp_meta_objset; 772 773 if (origin == NULL) 774 origin = dp->dp_origin_snap; 775 776 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 777 ASSERT(origin == NULL || dsl_dataset_phys(origin)->ds_num_children > 0); 778 ASSERT(dmu_tx_is_syncing(tx)); 779 ASSERT(dsl_dir_phys(dd)->dd_head_dataset_obj == 0); 780 781 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 782 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 783 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 784 dmu_buf_will_dirty(dbuf, tx); 785 dsphys = dbuf->db_data; 786 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 787 dsphys->ds_dir_obj = dd->dd_object; 788 dsphys->ds_flags = flags; 789 dsphys->ds_fsid_guid = unique_create(); 790 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 791 sizeof (dsphys->ds_guid)); 792 dsphys->ds_snapnames_zapobj = 793 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 794 DMU_OT_NONE, 0, tx); 795 dsphys->ds_creation_time = gethrestime_sec(); 796 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 797 798 if (origin == NULL) { 799 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 800 } else { 801 dsl_dataset_t *ohds; /* head of the origin snapshot */ 802 803 dsphys->ds_prev_snap_obj = origin->ds_object; 804 dsphys->ds_prev_snap_txg = 805 dsl_dataset_phys(origin)->ds_creation_txg; 806 dsphys->ds_referenced_bytes = 807 dsl_dataset_phys(origin)->ds_referenced_bytes; 808 dsphys->ds_compressed_bytes = 809 dsl_dataset_phys(origin)->ds_compressed_bytes; 810 dsphys->ds_uncompressed_bytes = 811 dsl_dataset_phys(origin)->ds_uncompressed_bytes; 812 dsphys->ds_bp = dsl_dataset_phys(origin)->ds_bp; 813 814 /* 815 * Inherit flags that describe the dataset's contents 816 * (INCONSISTENT) or properties (Case Insensitive). 817 */ 818 dsphys->ds_flags |= dsl_dataset_phys(origin)->ds_flags & 819 (DS_FLAG_INCONSISTENT | DS_FLAG_CI_DATASET); 820 821 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 822 if (origin->ds_feature_inuse[f]) 823 dsl_dataset_activate_feature(dsobj, f, tx); 824 } 825 826 dmu_buf_will_dirty(origin->ds_dbuf, tx); 827 dsl_dataset_phys(origin)->ds_num_children++; 828 829 VERIFY0(dsl_dataset_hold_obj(dp, 830 dsl_dir_phys(origin->ds_dir)->dd_head_dataset_obj, 831 FTAG, &ohds)); 832 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 833 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 834 dsl_dataset_rele(ohds, FTAG); 835 836 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 837 if (dsl_dataset_phys(origin)->ds_next_clones_obj == 0) { 838 dsl_dataset_phys(origin)->ds_next_clones_obj = 839 zap_create(mos, 840 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 841 } 842 VERIFY0(zap_add_int(mos, 843 dsl_dataset_phys(origin)->ds_next_clones_obj, 844 dsobj, tx)); 845 } 846 847 dmu_buf_will_dirty(dd->dd_dbuf, tx); 848 dsl_dir_phys(dd)->dd_origin_obj = origin->ds_object; 849 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 850 if (dsl_dir_phys(origin->ds_dir)->dd_clones == 0) { 851 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 852 dsl_dir_phys(origin->ds_dir)->dd_clones = 853 zap_create(mos, 854 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 855 } 856 VERIFY0(zap_add_int(mos, 857 dsl_dir_phys(origin->ds_dir)->dd_clones, 858 dsobj, tx)); 859 } 860 } 861 862 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 863 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 864 865 dmu_buf_rele(dbuf, FTAG); 866 867 dmu_buf_will_dirty(dd->dd_dbuf, tx); 868 dsl_dir_phys(dd)->dd_head_dataset_obj = dsobj; 869 870 return (dsobj); 871 } 872 873 static void 874 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 875 { 876 objset_t *os; 877 878 VERIFY0(dmu_objset_from_ds(ds, &os)); 879 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 880 dsl_dataset_dirty(ds, tx); 881 } 882 883 uint64_t 884 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 885 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 886 { 887 dsl_pool_t *dp = pdd->dd_pool; 888 uint64_t dsobj, ddobj; 889 dsl_dir_t *dd; 890 891 ASSERT(dmu_tx_is_syncing(tx)); 892 ASSERT(lastname[0] != '@'); 893 894 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 895 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 896 897 dsobj = dsl_dataset_create_sync_dd(dd, origin, 898 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 899 900 dsl_deleg_set_create_perms(dd, tx, cr); 901 902 /* 903 * Since we're creating a new node we know it's a leaf, so we can 904 * initialize the counts if the limit feature is active. 905 */ 906 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) { 907 uint64_t cnt = 0; 908 objset_t *os = dd->dd_pool->dp_meta_objset; 909 910 dsl_dir_zapify(dd, tx); 911 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT, 912 sizeof (cnt), 1, &cnt, tx)); 913 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT, 914 sizeof (cnt), 1, &cnt, tx)); 915 } 916 917 dsl_dir_rele(dd, FTAG); 918 919 /* 920 * If we are creating a clone, make sure we zero out any stale 921 * data from the origin snapshots zil header. 922 */ 923 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 924 dsl_dataset_t *ds; 925 926 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 927 dsl_dataset_zero_zil(ds, tx); 928 dsl_dataset_rele(ds, FTAG); 929 } 930 931 return (dsobj); 932 } 933 934 /* 935 * The unique space in the head dataset can be calculated by subtracting 936 * the space used in the most recent snapshot, that is still being used 937 * in this file system, from the space currently in use. To figure out 938 * the space in the most recent snapshot still in use, we need to take 939 * the total space used in the snapshot and subtract out the space that 940 * has been freed up since the snapshot was taken. 941 */ 942 void 943 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 944 { 945 uint64_t mrs_used; 946 uint64_t dlused, dlcomp, dluncomp; 947 948 ASSERT(!ds->ds_is_snapshot); 949 950 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) 951 mrs_used = dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes; 952 else 953 mrs_used = 0; 954 955 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 956 957 ASSERT3U(dlused, <=, mrs_used); 958 dsl_dataset_phys(ds)->ds_unique_bytes = 959 dsl_dataset_phys(ds)->ds_referenced_bytes - (mrs_used - dlused); 960 961 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 962 SPA_VERSION_UNIQUE_ACCURATE) 963 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 964 } 965 966 void 967 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 968 dmu_tx_t *tx) 969 { 970 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 971 uint64_t count; 972 int err; 973 974 ASSERT(dsl_dataset_phys(ds)->ds_num_children >= 2); 975 err = zap_remove_int(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 976 obj, tx); 977 /* 978 * The err should not be ENOENT, but a bug in a previous version 979 * of the code could cause upgrade_clones_cb() to not set 980 * ds_next_snap_obj when it should, leading to a missing entry. 981 * If we knew that the pool was created after 982 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 983 * ENOENT. However, at least we can check that we don't have 984 * too many entries in the next_clones_obj even after failing to 985 * remove this one. 986 */ 987 if (err != ENOENT) 988 VERIFY0(err); 989 ASSERT0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 990 &count)); 991 ASSERT3U(count, <=, dsl_dataset_phys(ds)->ds_num_children - 2); 992 } 993 994 995 blkptr_t * 996 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 997 { 998 return (&dsl_dataset_phys(ds)->ds_bp); 999 } 1000 1001 void 1002 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1003 { 1004 ASSERT(dmu_tx_is_syncing(tx)); 1005 /* If it's the meta-objset, set dp_meta_rootbp */ 1006 if (ds == NULL) { 1007 tx->tx_pool->dp_meta_rootbp = *bp; 1008 } else { 1009 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1010 dsl_dataset_phys(ds)->ds_bp = *bp; 1011 } 1012 } 1013 1014 spa_t * 1015 dsl_dataset_get_spa(dsl_dataset_t *ds) 1016 { 1017 return (ds->ds_dir->dd_pool->dp_spa); 1018 } 1019 1020 void 1021 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1022 { 1023 dsl_pool_t *dp; 1024 1025 if (ds == NULL) /* this is the meta-objset */ 1026 return; 1027 1028 ASSERT(ds->ds_objset != NULL); 1029 1030 if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) 1031 panic("dirtying snapshot!"); 1032 1033 dp = ds->ds_dir->dd_pool; 1034 1035 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 1036 /* up the hold count until we can be written out */ 1037 dmu_buf_add_ref(ds->ds_dbuf, ds); 1038 } 1039 } 1040 1041 boolean_t 1042 dsl_dataset_is_dirty(dsl_dataset_t *ds) 1043 { 1044 for (int t = 0; t < TXG_SIZE; t++) { 1045 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 1046 ds, t)) 1047 return (B_TRUE); 1048 } 1049 return (B_FALSE); 1050 } 1051 1052 static int 1053 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1054 { 1055 uint64_t asize; 1056 1057 if (!dmu_tx_is_syncing(tx)) 1058 return (0); 1059 1060 /* 1061 * If there's an fs-only reservation, any blocks that might become 1062 * owned by the snapshot dataset must be accommodated by space 1063 * outside of the reservation. 1064 */ 1065 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 1066 asize = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, ds->ds_reserved); 1067 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 1068 return (SET_ERROR(ENOSPC)); 1069 1070 /* 1071 * Propagate any reserved space for this snapshot to other 1072 * snapshot checks in this sync group. 1073 */ 1074 if (asize > 0) 1075 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1076 1077 return (0); 1078 } 1079 1080 typedef struct dsl_dataset_snapshot_arg { 1081 nvlist_t *ddsa_snaps; 1082 nvlist_t *ddsa_props; 1083 nvlist_t *ddsa_errors; 1084 cred_t *ddsa_cr; 1085 } dsl_dataset_snapshot_arg_t; 1086 1087 int 1088 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 1089 dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr) 1090 { 1091 int error; 1092 uint64_t value; 1093 1094 ds->ds_trysnap_txg = tx->tx_txg; 1095 1096 if (!dmu_tx_is_syncing(tx)) 1097 return (0); 1098 1099 /* 1100 * We don't allow multiple snapshots of the same txg. If there 1101 * is already one, try again. 1102 */ 1103 if (dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg) 1104 return (SET_ERROR(EAGAIN)); 1105 1106 /* 1107 * Check for conflicting snapshot name. 1108 */ 1109 error = dsl_dataset_snap_lookup(ds, snapname, &value); 1110 if (error == 0) 1111 return (SET_ERROR(EEXIST)); 1112 if (error != ENOENT) 1113 return (error); 1114 1115 /* 1116 * We don't allow taking snapshots of inconsistent datasets, such as 1117 * those into which we are currently receiving. However, if we are 1118 * creating this snapshot as part of a receive, this check will be 1119 * executed atomically with respect to the completion of the receive 1120 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 1121 * case we ignore this, knowing it will be fixed up for us shortly in 1122 * dmu_recv_end_sync(). 1123 */ 1124 if (!recv && DS_IS_INCONSISTENT(ds)) 1125 return (SET_ERROR(EBUSY)); 1126 1127 /* 1128 * Skip the check for temporary snapshots or if we have already checked 1129 * the counts in dsl_dataset_snapshot_check. This means we really only 1130 * check the count here when we're receiving a stream. 1131 */ 1132 if (cnt != 0 && cr != NULL) { 1133 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1134 ZFS_PROP_SNAPSHOT_LIMIT, NULL, cr); 1135 if (error != 0) 1136 return (error); 1137 } 1138 1139 error = dsl_dataset_snapshot_reserve_space(ds, tx); 1140 if (error != 0) 1141 return (error); 1142 1143 return (0); 1144 } 1145 1146 static int 1147 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 1148 { 1149 dsl_dataset_snapshot_arg_t *ddsa = arg; 1150 dsl_pool_t *dp = dmu_tx_pool(tx); 1151 nvpair_t *pair; 1152 int rv = 0; 1153 1154 /* 1155 * Pre-compute how many total new snapshots will be created for each 1156 * level in the tree and below. This is needed for validating the 1157 * snapshot limit when either taking a recursive snapshot or when 1158 * taking multiple snapshots. 1159 * 1160 * The problem is that the counts are not actually adjusted when 1161 * we are checking, only when we finally sync. For a single snapshot, 1162 * this is easy, the count will increase by 1 at each node up the tree, 1163 * but its more complicated for the recursive/multiple snapshot case. 1164 * 1165 * The dsl_fs_ss_limit_check function does recursively check the count 1166 * at each level up the tree but since it is validating each snapshot 1167 * independently we need to be sure that we are validating the complete 1168 * count for the entire set of snapshots. We do this by rolling up the 1169 * counts for each component of the name into an nvlist and then 1170 * checking each of those cases with the aggregated count. 1171 * 1172 * This approach properly handles not only the recursive snapshot 1173 * case (where we get all of those on the ddsa_snaps list) but also 1174 * the sibling case (e.g. snapshot a/b and a/c so that we will also 1175 * validate the limit on 'a' using a count of 2). 1176 * 1177 * We validate the snapshot names in the third loop and only report 1178 * name errors once. 1179 */ 1180 if (dmu_tx_is_syncing(tx)) { 1181 nvlist_t *cnt_track = NULL; 1182 cnt_track = fnvlist_alloc(); 1183 1184 /* Rollup aggregated counts into the cnt_track list */ 1185 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1186 pair != NULL; 1187 pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1188 char *pdelim; 1189 uint64_t val; 1190 char nm[MAXPATHLEN]; 1191 1192 (void) strlcpy(nm, nvpair_name(pair), sizeof (nm)); 1193 pdelim = strchr(nm, '@'); 1194 if (pdelim == NULL) 1195 continue; 1196 *pdelim = '\0'; 1197 1198 do { 1199 if (nvlist_lookup_uint64(cnt_track, nm, 1200 &val) == 0) { 1201 /* update existing entry */ 1202 fnvlist_add_uint64(cnt_track, nm, 1203 val + 1); 1204 } else { 1205 /* add to list */ 1206 fnvlist_add_uint64(cnt_track, nm, 1); 1207 } 1208 1209 pdelim = strrchr(nm, '/'); 1210 if (pdelim != NULL) 1211 *pdelim = '\0'; 1212 } while (pdelim != NULL); 1213 } 1214 1215 /* Check aggregated counts at each level */ 1216 for (pair = nvlist_next_nvpair(cnt_track, NULL); 1217 pair != NULL; pair = nvlist_next_nvpair(cnt_track, pair)) { 1218 int error = 0; 1219 char *name; 1220 uint64_t cnt = 0; 1221 dsl_dataset_t *ds; 1222 1223 name = nvpair_name(pair); 1224 cnt = fnvpair_value_uint64(pair); 1225 ASSERT(cnt > 0); 1226 1227 error = dsl_dataset_hold(dp, name, FTAG, &ds); 1228 if (error == 0) { 1229 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1230 ZFS_PROP_SNAPSHOT_LIMIT, NULL, 1231 ddsa->ddsa_cr); 1232 dsl_dataset_rele(ds, FTAG); 1233 } 1234 1235 if (error != 0) { 1236 if (ddsa->ddsa_errors != NULL) 1237 fnvlist_add_int32(ddsa->ddsa_errors, 1238 name, error); 1239 rv = error; 1240 /* only report one error for this check */ 1241 break; 1242 } 1243 } 1244 nvlist_free(cnt_track); 1245 } 1246 1247 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1248 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1249 int error = 0; 1250 dsl_dataset_t *ds; 1251 char *name, *atp; 1252 char dsname[MAXNAMELEN]; 1253 1254 name = nvpair_name(pair); 1255 if (strlen(name) >= MAXNAMELEN) 1256 error = SET_ERROR(ENAMETOOLONG); 1257 if (error == 0) { 1258 atp = strchr(name, '@'); 1259 if (atp == NULL) 1260 error = SET_ERROR(EINVAL); 1261 if (error == 0) 1262 (void) strlcpy(dsname, name, atp - name + 1); 1263 } 1264 if (error == 0) 1265 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1266 if (error == 0) { 1267 /* passing 0/NULL skips dsl_fs_ss_limit_check */ 1268 error = dsl_dataset_snapshot_check_impl(ds, 1269 atp + 1, tx, B_FALSE, 0, NULL); 1270 dsl_dataset_rele(ds, FTAG); 1271 } 1272 1273 if (error != 0) { 1274 if (ddsa->ddsa_errors != NULL) { 1275 fnvlist_add_int32(ddsa->ddsa_errors, 1276 name, error); 1277 } 1278 rv = error; 1279 } 1280 } 1281 1282 return (rv); 1283 } 1284 1285 void 1286 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1287 dmu_tx_t *tx) 1288 { 1289 static zil_header_t zero_zil; 1290 1291 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1292 dmu_buf_t *dbuf; 1293 dsl_dataset_phys_t *dsphys; 1294 uint64_t dsobj, crtxg; 1295 objset_t *mos = dp->dp_meta_objset; 1296 objset_t *os; 1297 1298 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1299 1300 /* 1301 * If we are on an old pool, the zil must not be active, in which 1302 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1303 */ 1304 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1305 dmu_objset_from_ds(ds, &os) != 0 || 1306 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1307 sizeof (zero_zil)) == 0); 1308 1309 dsl_fs_ss_count_adjust(ds->ds_dir, 1, DD_FIELD_SNAPSHOT_COUNT, tx); 1310 1311 /* 1312 * The origin's ds_creation_txg has to be < TXG_INITIAL 1313 */ 1314 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1315 crtxg = 1; 1316 else 1317 crtxg = tx->tx_txg; 1318 1319 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1320 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1321 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1322 dmu_buf_will_dirty(dbuf, tx); 1323 dsphys = dbuf->db_data; 1324 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1325 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1326 dsphys->ds_fsid_guid = unique_create(); 1327 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1328 sizeof (dsphys->ds_guid)); 1329 dsphys->ds_prev_snap_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 1330 dsphys->ds_prev_snap_txg = dsl_dataset_phys(ds)->ds_prev_snap_txg; 1331 dsphys->ds_next_snap_obj = ds->ds_object; 1332 dsphys->ds_num_children = 1; 1333 dsphys->ds_creation_time = gethrestime_sec(); 1334 dsphys->ds_creation_txg = crtxg; 1335 dsphys->ds_deadlist_obj = dsl_dataset_phys(ds)->ds_deadlist_obj; 1336 dsphys->ds_referenced_bytes = dsl_dataset_phys(ds)->ds_referenced_bytes; 1337 dsphys->ds_compressed_bytes = dsl_dataset_phys(ds)->ds_compressed_bytes; 1338 dsphys->ds_uncompressed_bytes = 1339 dsl_dataset_phys(ds)->ds_uncompressed_bytes; 1340 dsphys->ds_flags = dsl_dataset_phys(ds)->ds_flags; 1341 dsphys->ds_bp = dsl_dataset_phys(ds)->ds_bp; 1342 dmu_buf_rele(dbuf, FTAG); 1343 1344 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1345 if (ds->ds_feature_inuse[f]) 1346 dsl_dataset_activate_feature(dsobj, f, tx); 1347 } 1348 1349 ASSERT3U(ds->ds_prev != 0, ==, 1350 dsl_dataset_phys(ds)->ds_prev_snap_obj != 0); 1351 if (ds->ds_prev) { 1352 uint64_t next_clones_obj = 1353 dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj; 1354 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1355 ds->ds_object || 1356 dsl_dataset_phys(ds->ds_prev)->ds_num_children > 1); 1357 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1358 ds->ds_object) { 1359 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1360 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==, 1361 dsl_dataset_phys(ds->ds_prev)->ds_creation_txg); 1362 dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj = dsobj; 1363 } else if (next_clones_obj != 0) { 1364 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1365 dsphys->ds_next_snap_obj, tx); 1366 VERIFY0(zap_add_int(mos, 1367 next_clones_obj, dsobj, tx)); 1368 } 1369 } 1370 1371 /* 1372 * If we have a reference-reservation on this dataset, we will 1373 * need to increase the amount of refreservation being charged 1374 * since our unique space is going to zero. 1375 */ 1376 if (ds->ds_reserved) { 1377 int64_t delta; 1378 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1379 delta = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, 1380 ds->ds_reserved); 1381 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1382 delta, 0, 0, tx); 1383 } 1384 1385 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1386 dsl_dataset_phys(ds)->ds_deadlist_obj = 1387 dsl_deadlist_clone(&ds->ds_deadlist, UINT64_MAX, 1388 dsl_dataset_phys(ds)->ds_prev_snap_obj, tx); 1389 dsl_deadlist_close(&ds->ds_deadlist); 1390 dsl_deadlist_open(&ds->ds_deadlist, mos, 1391 dsl_dataset_phys(ds)->ds_deadlist_obj); 1392 dsl_deadlist_add_key(&ds->ds_deadlist, 1393 dsl_dataset_phys(ds)->ds_prev_snap_txg, tx); 1394 1395 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, <, tx->tx_txg); 1396 dsl_dataset_phys(ds)->ds_prev_snap_obj = dsobj; 1397 dsl_dataset_phys(ds)->ds_prev_snap_txg = crtxg; 1398 dsl_dataset_phys(ds)->ds_unique_bytes = 0; 1399 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1400 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1401 1402 VERIFY0(zap_add(mos, dsl_dataset_phys(ds)->ds_snapnames_zapobj, 1403 snapname, 8, 1, &dsobj, tx)); 1404 1405 if (ds->ds_prev) 1406 dsl_dataset_rele(ds->ds_prev, ds); 1407 VERIFY0(dsl_dataset_hold_obj(dp, 1408 dsl_dataset_phys(ds)->ds_prev_snap_obj, ds, &ds->ds_prev)); 1409 1410 dsl_scan_ds_snapshotted(ds, tx); 1411 1412 dsl_dir_snap_cmtime_update(ds->ds_dir); 1413 1414 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1415 } 1416 1417 static void 1418 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1419 { 1420 dsl_dataset_snapshot_arg_t *ddsa = arg; 1421 dsl_pool_t *dp = dmu_tx_pool(tx); 1422 nvpair_t *pair; 1423 1424 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1425 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1426 dsl_dataset_t *ds; 1427 char *name, *atp; 1428 char dsname[MAXNAMELEN]; 1429 1430 name = nvpair_name(pair); 1431 atp = strchr(name, '@'); 1432 (void) strlcpy(dsname, name, atp - name + 1); 1433 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1434 1435 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1436 if (ddsa->ddsa_props != NULL) { 1437 dsl_props_set_sync_impl(ds->ds_prev, 1438 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1439 } 1440 dsl_dataset_rele(ds, FTAG); 1441 } 1442 } 1443 1444 /* 1445 * The snapshots must all be in the same pool. 1446 * All-or-nothing: if there are any failures, nothing will be modified. 1447 */ 1448 int 1449 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1450 { 1451 dsl_dataset_snapshot_arg_t ddsa; 1452 nvpair_t *pair; 1453 boolean_t needsuspend; 1454 int error; 1455 spa_t *spa; 1456 char *firstname; 1457 nvlist_t *suspended = NULL; 1458 1459 pair = nvlist_next_nvpair(snaps, NULL); 1460 if (pair == NULL) 1461 return (0); 1462 firstname = nvpair_name(pair); 1463 1464 error = spa_open(firstname, &spa, FTAG); 1465 if (error != 0) 1466 return (error); 1467 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1468 spa_close(spa, FTAG); 1469 1470 if (needsuspend) { 1471 suspended = fnvlist_alloc(); 1472 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1473 pair = nvlist_next_nvpair(snaps, pair)) { 1474 char fsname[MAXNAMELEN]; 1475 char *snapname = nvpair_name(pair); 1476 char *atp; 1477 void *cookie; 1478 1479 atp = strchr(snapname, '@'); 1480 if (atp == NULL) { 1481 error = SET_ERROR(EINVAL); 1482 break; 1483 } 1484 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1485 1486 error = zil_suspend(fsname, &cookie); 1487 if (error != 0) 1488 break; 1489 fnvlist_add_uint64(suspended, fsname, 1490 (uintptr_t)cookie); 1491 } 1492 } 1493 1494 ddsa.ddsa_snaps = snaps; 1495 ddsa.ddsa_props = props; 1496 ddsa.ddsa_errors = errors; 1497 ddsa.ddsa_cr = CRED(); 1498 1499 if (error == 0) { 1500 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1501 dsl_dataset_snapshot_sync, &ddsa, 1502 fnvlist_num_pairs(snaps) * 3, ZFS_SPACE_CHECK_NORMAL); 1503 } 1504 1505 if (suspended != NULL) { 1506 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1507 pair = nvlist_next_nvpair(suspended, pair)) { 1508 zil_resume((void *)(uintptr_t) 1509 fnvpair_value_uint64(pair)); 1510 } 1511 fnvlist_free(suspended); 1512 } 1513 1514 return (error); 1515 } 1516 1517 typedef struct dsl_dataset_snapshot_tmp_arg { 1518 const char *ddsta_fsname; 1519 const char *ddsta_snapname; 1520 minor_t ddsta_cleanup_minor; 1521 const char *ddsta_htag; 1522 } dsl_dataset_snapshot_tmp_arg_t; 1523 1524 static int 1525 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1526 { 1527 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1528 dsl_pool_t *dp = dmu_tx_pool(tx); 1529 dsl_dataset_t *ds; 1530 int error; 1531 1532 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1533 if (error != 0) 1534 return (error); 1535 1536 /* NULL cred means no limit check for tmp snapshot */ 1537 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1538 tx, B_FALSE, 0, NULL); 1539 if (error != 0) { 1540 dsl_dataset_rele(ds, FTAG); 1541 return (error); 1542 } 1543 1544 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1545 dsl_dataset_rele(ds, FTAG); 1546 return (SET_ERROR(ENOTSUP)); 1547 } 1548 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1549 B_TRUE, tx); 1550 if (error != 0) { 1551 dsl_dataset_rele(ds, FTAG); 1552 return (error); 1553 } 1554 1555 dsl_dataset_rele(ds, FTAG); 1556 return (0); 1557 } 1558 1559 static void 1560 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1561 { 1562 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1563 dsl_pool_t *dp = dmu_tx_pool(tx); 1564 dsl_dataset_t *ds; 1565 1566 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1567 1568 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1569 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1570 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1571 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1572 1573 dsl_dataset_rele(ds, FTAG); 1574 } 1575 1576 int 1577 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1578 minor_t cleanup_minor, const char *htag) 1579 { 1580 dsl_dataset_snapshot_tmp_arg_t ddsta; 1581 int error; 1582 spa_t *spa; 1583 boolean_t needsuspend; 1584 void *cookie; 1585 1586 ddsta.ddsta_fsname = fsname; 1587 ddsta.ddsta_snapname = snapname; 1588 ddsta.ddsta_cleanup_minor = cleanup_minor; 1589 ddsta.ddsta_htag = htag; 1590 1591 error = spa_open(fsname, &spa, FTAG); 1592 if (error != 0) 1593 return (error); 1594 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1595 spa_close(spa, FTAG); 1596 1597 if (needsuspend) { 1598 error = zil_suspend(fsname, &cookie); 1599 if (error != 0) 1600 return (error); 1601 } 1602 1603 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1604 dsl_dataset_snapshot_tmp_sync, &ddsta, 3, ZFS_SPACE_CHECK_RESERVED); 1605 1606 if (needsuspend) 1607 zil_resume(cookie); 1608 return (error); 1609 } 1610 1611 1612 void 1613 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1614 { 1615 ASSERT(dmu_tx_is_syncing(tx)); 1616 ASSERT(ds->ds_objset != NULL); 1617 ASSERT(dsl_dataset_phys(ds)->ds_next_snap_obj == 0); 1618 1619 /* 1620 * in case we had to change ds_fsid_guid when we opened it, 1621 * sync it out now. 1622 */ 1623 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1624 dsl_dataset_phys(ds)->ds_fsid_guid = ds->ds_fsid_guid; 1625 1626 if (ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] != 0) { 1627 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1628 ds->ds_object, DS_FIELD_RESUME_OBJECT, 8, 1, 1629 &ds->ds_resume_object[tx->tx_txg & TXG_MASK], tx)); 1630 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1631 ds->ds_object, DS_FIELD_RESUME_OFFSET, 8, 1, 1632 &ds->ds_resume_offset[tx->tx_txg & TXG_MASK], tx)); 1633 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1634 ds->ds_object, DS_FIELD_RESUME_BYTES, 8, 1, 1635 &ds->ds_resume_bytes[tx->tx_txg & TXG_MASK], tx)); 1636 ds->ds_resume_object[tx->tx_txg & TXG_MASK] = 0; 1637 ds->ds_resume_offset[tx->tx_txg & TXG_MASK] = 0; 1638 ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] = 0; 1639 } 1640 1641 dmu_objset_sync(ds->ds_objset, zio, tx); 1642 1643 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1644 if (ds->ds_feature_activation_needed[f]) { 1645 if (ds->ds_feature_inuse[f]) 1646 continue; 1647 dsl_dataset_activate_feature(ds->ds_object, f, tx); 1648 ds->ds_feature_inuse[f] = B_TRUE; 1649 } 1650 } 1651 } 1652 1653 static void 1654 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1655 { 1656 uint64_t count = 0; 1657 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1658 zap_cursor_t zc; 1659 zap_attribute_t za; 1660 nvlist_t *propval = fnvlist_alloc(); 1661 nvlist_t *val = fnvlist_alloc(); 1662 1663 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1664 1665 /* 1666 * There may be missing entries in ds_next_clones_obj 1667 * due to a bug in a previous version of the code. 1668 * Only trust it if it has the right number of entries. 1669 */ 1670 if (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) { 1671 VERIFY0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1672 &count)); 1673 } 1674 if (count != dsl_dataset_phys(ds)->ds_num_children - 1) 1675 goto fail; 1676 for (zap_cursor_init(&zc, mos, 1677 dsl_dataset_phys(ds)->ds_next_clones_obj); 1678 zap_cursor_retrieve(&zc, &za) == 0; 1679 zap_cursor_advance(&zc)) { 1680 dsl_dataset_t *clone; 1681 char buf[ZFS_MAXNAMELEN]; 1682 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1683 za.za_first_integer, FTAG, &clone)); 1684 dsl_dir_name(clone->ds_dir, buf); 1685 fnvlist_add_boolean(val, buf); 1686 dsl_dataset_rele(clone, FTAG); 1687 } 1688 zap_cursor_fini(&zc); 1689 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1690 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval); 1691 fail: 1692 nvlist_free(val); 1693 nvlist_free(propval); 1694 } 1695 1696 static void 1697 get_receive_resume_stats(dsl_dataset_t *ds, nvlist_t *nv) 1698 { 1699 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1700 1701 if (dsl_dataset_has_resume_receive_state(ds)) { 1702 char *str; 1703 void *packed; 1704 uint8_t *compressed; 1705 uint64_t val; 1706 nvlist_t *token_nv = fnvlist_alloc(); 1707 size_t packed_size, compressed_size; 1708 1709 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1710 DS_FIELD_RESUME_FROMGUID, sizeof (val), 1, &val) == 0) { 1711 fnvlist_add_uint64(token_nv, "fromguid", val); 1712 } 1713 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1714 DS_FIELD_RESUME_OBJECT, sizeof (val), 1, &val) == 0) { 1715 fnvlist_add_uint64(token_nv, "object", val); 1716 } 1717 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1718 DS_FIELD_RESUME_OFFSET, sizeof (val), 1, &val) == 0) { 1719 fnvlist_add_uint64(token_nv, "offset", val); 1720 } 1721 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1722 DS_FIELD_RESUME_BYTES, sizeof (val), 1, &val) == 0) { 1723 fnvlist_add_uint64(token_nv, "bytes", val); 1724 } 1725 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1726 DS_FIELD_RESUME_TOGUID, sizeof (val), 1, &val) == 0) { 1727 fnvlist_add_uint64(token_nv, "toguid", val); 1728 } 1729 char buf[256]; 1730 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1731 DS_FIELD_RESUME_TONAME, 1, sizeof (buf), buf) == 0) { 1732 fnvlist_add_string(token_nv, "toname", buf); 1733 } 1734 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1735 DS_FIELD_RESUME_EMBEDOK) == 0) { 1736 fnvlist_add_boolean(token_nv, "embedok"); 1737 } 1738 packed = fnvlist_pack(token_nv, &packed_size); 1739 fnvlist_free(token_nv); 1740 compressed = kmem_alloc(packed_size, KM_SLEEP); 1741 1742 compressed_size = gzip_compress(packed, compressed, 1743 packed_size, packed_size, 6); 1744 1745 zio_cksum_t cksum; 1746 fletcher_4_native(compressed, compressed_size, NULL, &cksum); 1747 1748 str = kmem_alloc(compressed_size * 2 + 1, KM_SLEEP); 1749 for (int i = 0; i < compressed_size; i++) { 1750 (void) sprintf(str + i * 2, "%02x", compressed[i]); 1751 } 1752 str[compressed_size * 2] = '\0'; 1753 char *propval = kmem_asprintf("%u-%llx-%llx-%s", 1754 ZFS_SEND_RESUME_TOKEN_VERSION, 1755 (longlong_t)cksum.zc_word[0], 1756 (longlong_t)packed_size, str); 1757 dsl_prop_nvlist_add_string(nv, 1758 ZFS_PROP_RECEIVE_RESUME_TOKEN, propval); 1759 kmem_free(packed, packed_size); 1760 kmem_free(str, compressed_size * 2 + 1); 1761 kmem_free(compressed, packed_size); 1762 strfree(propval); 1763 } 1764 } 1765 1766 void 1767 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1768 { 1769 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1770 uint64_t refd, avail, uobjs, aobjs, ratio; 1771 1772 ASSERT(dsl_pool_config_held(dp)); 1773 1774 ratio = dsl_dataset_phys(ds)->ds_compressed_bytes == 0 ? 100 : 1775 (dsl_dataset_phys(ds)->ds_uncompressed_bytes * 100 / 1776 dsl_dataset_phys(ds)->ds_compressed_bytes); 1777 1778 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio); 1779 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 1780 dsl_dataset_phys(ds)->ds_uncompressed_bytes); 1781 1782 if (ds->ds_is_snapshot) { 1783 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio); 1784 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1785 dsl_dataset_phys(ds)->ds_unique_bytes); 1786 get_clones_stat(ds, nv); 1787 } else { 1788 if (ds->ds_prev != NULL && ds->ds_prev != dp->dp_origin_snap) { 1789 char buf[MAXNAMELEN]; 1790 dsl_dataset_name(ds->ds_prev, buf); 1791 dsl_prop_nvlist_add_string(nv, ZFS_PROP_PREV_SNAP, buf); 1792 } 1793 1794 dsl_dir_stats(ds->ds_dir, nv); 1795 } 1796 1797 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1798 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1799 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1800 1801 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1802 dsl_dataset_phys(ds)->ds_creation_time); 1803 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1804 dsl_dataset_phys(ds)->ds_creation_txg); 1805 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1806 ds->ds_quota); 1807 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1808 ds->ds_reserved); 1809 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1810 dsl_dataset_phys(ds)->ds_guid); 1811 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 1812 dsl_dataset_phys(ds)->ds_unique_bytes); 1813 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 1814 ds->ds_object); 1815 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 1816 ds->ds_userrefs); 1817 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 1818 DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1819 1820 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 1821 uint64_t written, comp, uncomp; 1822 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1823 dsl_dataset_t *prev; 1824 1825 int err = dsl_dataset_hold_obj(dp, 1826 dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &prev); 1827 if (err == 0) { 1828 err = dsl_dataset_space_written(prev, ds, &written, 1829 &comp, &uncomp); 1830 dsl_dataset_rele(prev, FTAG); 1831 if (err == 0) { 1832 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 1833 written); 1834 } 1835 } 1836 } 1837 1838 if (!dsl_dataset_is_snapshot(ds)) { 1839 /* 1840 * A failed "newfs" (e.g. full) resumable receive leaves 1841 * the stats set on this dataset. Check here for the prop. 1842 */ 1843 get_receive_resume_stats(ds, nv); 1844 1845 /* 1846 * A failed incremental resumable receive leaves the 1847 * stats set on our child named "%recv". Check the child 1848 * for the prop. 1849 */ 1850 char recvname[ZFS_MAXNAMELEN]; 1851 dsl_dataset_t *recv_ds; 1852 dsl_dataset_name(ds, recvname); 1853 (void) strcat(recvname, "/"); 1854 (void) strcat(recvname, recv_clone_name); 1855 if (dsl_dataset_hold(dp, recvname, FTAG, &recv_ds) == 0) { 1856 get_receive_resume_stats(recv_ds, nv); 1857 dsl_dataset_rele(recv_ds, FTAG); 1858 } 1859 } 1860 } 1861 1862 void 1863 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1864 { 1865 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1866 ASSERT(dsl_pool_config_held(dp)); 1867 1868 stat->dds_creation_txg = dsl_dataset_phys(ds)->ds_creation_txg; 1869 stat->dds_inconsistent = 1870 dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT; 1871 stat->dds_guid = dsl_dataset_phys(ds)->ds_guid; 1872 stat->dds_origin[0] = '\0'; 1873 if (ds->ds_is_snapshot) { 1874 stat->dds_is_snapshot = B_TRUE; 1875 stat->dds_num_clones = 1876 dsl_dataset_phys(ds)->ds_num_children - 1; 1877 } else { 1878 stat->dds_is_snapshot = B_FALSE; 1879 stat->dds_num_clones = 0; 1880 1881 if (dsl_dir_is_clone(ds->ds_dir)) { 1882 dsl_dataset_t *ods; 1883 1884 VERIFY0(dsl_dataset_hold_obj(dp, 1885 dsl_dir_phys(ds->ds_dir)->dd_origin_obj, 1886 FTAG, &ods)); 1887 dsl_dataset_name(ods, stat->dds_origin); 1888 dsl_dataset_rele(ods, FTAG); 1889 } 1890 } 1891 } 1892 1893 uint64_t 1894 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1895 { 1896 return (ds->ds_fsid_guid); 1897 } 1898 1899 void 1900 dsl_dataset_space(dsl_dataset_t *ds, 1901 uint64_t *refdbytesp, uint64_t *availbytesp, 1902 uint64_t *usedobjsp, uint64_t *availobjsp) 1903 { 1904 *refdbytesp = dsl_dataset_phys(ds)->ds_referenced_bytes; 1905 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1906 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) 1907 *availbytesp += 1908 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes; 1909 if (ds->ds_quota != 0) { 1910 /* 1911 * Adjust available bytes according to refquota 1912 */ 1913 if (*refdbytesp < ds->ds_quota) 1914 *availbytesp = MIN(*availbytesp, 1915 ds->ds_quota - *refdbytesp); 1916 else 1917 *availbytesp = 0; 1918 } 1919 *usedobjsp = BP_GET_FILL(&dsl_dataset_phys(ds)->ds_bp); 1920 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1921 } 1922 1923 boolean_t 1924 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 1925 { 1926 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1927 1928 ASSERT(dsl_pool_config_held(dp)); 1929 if (snap == NULL) 1930 return (B_FALSE); 1931 if (dsl_dataset_phys(ds)->ds_bp.blk_birth > 1932 dsl_dataset_phys(snap)->ds_creation_txg) { 1933 objset_t *os, *os_snap; 1934 /* 1935 * It may be that only the ZIL differs, because it was 1936 * reset in the head. Don't count that as being 1937 * modified. 1938 */ 1939 if (dmu_objset_from_ds(ds, &os) != 0) 1940 return (B_TRUE); 1941 if (dmu_objset_from_ds(snap, &os_snap) != 0) 1942 return (B_TRUE); 1943 return (bcmp(&os->os_phys->os_meta_dnode, 1944 &os_snap->os_phys->os_meta_dnode, 1945 sizeof (os->os_phys->os_meta_dnode)) != 0); 1946 } 1947 return (B_FALSE); 1948 } 1949 1950 typedef struct dsl_dataset_rename_snapshot_arg { 1951 const char *ddrsa_fsname; 1952 const char *ddrsa_oldsnapname; 1953 const char *ddrsa_newsnapname; 1954 boolean_t ddrsa_recursive; 1955 dmu_tx_t *ddrsa_tx; 1956 } dsl_dataset_rename_snapshot_arg_t; 1957 1958 /* ARGSUSED */ 1959 static int 1960 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 1961 dsl_dataset_t *hds, void *arg) 1962 { 1963 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1964 int error; 1965 uint64_t val; 1966 1967 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 1968 if (error != 0) { 1969 /* ignore nonexistent snapshots */ 1970 return (error == ENOENT ? 0 : error); 1971 } 1972 1973 /* new name should not exist */ 1974 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 1975 if (error == 0) 1976 error = SET_ERROR(EEXIST); 1977 else if (error == ENOENT) 1978 error = 0; 1979 1980 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1981 if (dsl_dir_namelen(hds->ds_dir) + 1 + 1982 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN) 1983 error = SET_ERROR(ENAMETOOLONG); 1984 1985 return (error); 1986 } 1987 1988 static int 1989 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 1990 { 1991 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 1992 dsl_pool_t *dp = dmu_tx_pool(tx); 1993 dsl_dataset_t *hds; 1994 int error; 1995 1996 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 1997 if (error != 0) 1998 return (error); 1999 2000 if (ddrsa->ddrsa_recursive) { 2001 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2002 dsl_dataset_rename_snapshot_check_impl, ddrsa, 2003 DS_FIND_CHILDREN); 2004 } else { 2005 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 2006 } 2007 dsl_dataset_rele(hds, FTAG); 2008 return (error); 2009 } 2010 2011 static int 2012 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 2013 dsl_dataset_t *hds, void *arg) 2014 { 2015 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2016 dsl_dataset_t *ds; 2017 uint64_t val; 2018 dmu_tx_t *tx = ddrsa->ddrsa_tx; 2019 int error; 2020 2021 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2022 ASSERT(error == 0 || error == ENOENT); 2023 if (error == ENOENT) { 2024 /* ignore nonexistent snapshots */ 2025 return (0); 2026 } 2027 2028 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 2029 2030 /* log before we change the name */ 2031 spa_history_log_internal_ds(ds, "rename", tx, 2032 "-> @%s", ddrsa->ddrsa_newsnapname); 2033 2034 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx, 2035 B_FALSE)); 2036 mutex_enter(&ds->ds_lock); 2037 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 2038 mutex_exit(&ds->ds_lock); 2039 VERIFY0(zap_add(dp->dp_meta_objset, 2040 dsl_dataset_phys(hds)->ds_snapnames_zapobj, 2041 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 2042 2043 dsl_dataset_rele(ds, FTAG); 2044 return (0); 2045 } 2046 2047 static void 2048 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 2049 { 2050 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2051 dsl_pool_t *dp = dmu_tx_pool(tx); 2052 dsl_dataset_t *hds; 2053 2054 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 2055 ddrsa->ddrsa_tx = tx; 2056 if (ddrsa->ddrsa_recursive) { 2057 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2058 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 2059 DS_FIND_CHILDREN)); 2060 } else { 2061 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 2062 } 2063 dsl_dataset_rele(hds, FTAG); 2064 } 2065 2066 int 2067 dsl_dataset_rename_snapshot(const char *fsname, 2068 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 2069 { 2070 dsl_dataset_rename_snapshot_arg_t ddrsa; 2071 2072 ddrsa.ddrsa_fsname = fsname; 2073 ddrsa.ddrsa_oldsnapname = oldsnapname; 2074 ddrsa.ddrsa_newsnapname = newsnapname; 2075 ddrsa.ddrsa_recursive = recursive; 2076 2077 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 2078 dsl_dataset_rename_snapshot_sync, &ddrsa, 2079 1, ZFS_SPACE_CHECK_RESERVED)); 2080 } 2081 2082 /* 2083 * If we're doing an ownership handoff, we need to make sure that there is 2084 * only one long hold on the dataset. We're not allowed to change anything here 2085 * so we don't permanently release the long hold or regular hold here. We want 2086 * to do this only when syncing to avoid the dataset unexpectedly going away 2087 * when we release the long hold. 2088 */ 2089 static int 2090 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 2091 { 2092 boolean_t held; 2093 2094 if (!dmu_tx_is_syncing(tx)) 2095 return (0); 2096 2097 if (owner != NULL) { 2098 VERIFY3P(ds->ds_owner, ==, owner); 2099 dsl_dataset_long_rele(ds, owner); 2100 } 2101 2102 held = dsl_dataset_long_held(ds); 2103 2104 if (owner != NULL) 2105 dsl_dataset_long_hold(ds, owner); 2106 2107 if (held) 2108 return (SET_ERROR(EBUSY)); 2109 2110 return (0); 2111 } 2112 2113 typedef struct dsl_dataset_rollback_arg { 2114 const char *ddra_fsname; 2115 void *ddra_owner; 2116 nvlist_t *ddra_result; 2117 } dsl_dataset_rollback_arg_t; 2118 2119 static int 2120 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 2121 { 2122 dsl_dataset_rollback_arg_t *ddra = arg; 2123 dsl_pool_t *dp = dmu_tx_pool(tx); 2124 dsl_dataset_t *ds; 2125 int64_t unused_refres_delta; 2126 int error; 2127 2128 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 2129 if (error != 0) 2130 return (error); 2131 2132 /* must not be a snapshot */ 2133 if (ds->ds_is_snapshot) { 2134 dsl_dataset_rele(ds, FTAG); 2135 return (SET_ERROR(EINVAL)); 2136 } 2137 2138 /* must have a most recent snapshot */ 2139 if (dsl_dataset_phys(ds)->ds_prev_snap_txg < TXG_INITIAL) { 2140 dsl_dataset_rele(ds, FTAG); 2141 return (SET_ERROR(EINVAL)); 2142 } 2143 2144 /* must not have any bookmarks after the most recent snapshot */ 2145 nvlist_t *proprequest = fnvlist_alloc(); 2146 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2147 nvlist_t *bookmarks = fnvlist_alloc(); 2148 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks); 2149 fnvlist_free(proprequest); 2150 if (error != 0) 2151 return (error); 2152 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL); 2153 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) { 2154 nvlist_t *valuenv = 2155 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair), 2156 zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2157 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value"); 2158 if (createtxg > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 2159 fnvlist_free(bookmarks); 2160 dsl_dataset_rele(ds, FTAG); 2161 return (SET_ERROR(EEXIST)); 2162 } 2163 } 2164 fnvlist_free(bookmarks); 2165 2166 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 2167 if (error != 0) { 2168 dsl_dataset_rele(ds, FTAG); 2169 return (error); 2170 } 2171 2172 /* 2173 * Check if the snap we are rolling back to uses more than 2174 * the refquota. 2175 */ 2176 if (ds->ds_quota != 0 && 2177 dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes > ds->ds_quota) { 2178 dsl_dataset_rele(ds, FTAG); 2179 return (SET_ERROR(EDQUOT)); 2180 } 2181 2182 /* 2183 * When we do the clone swap, we will temporarily use more space 2184 * due to the refreservation (the head will no longer have any 2185 * unique space, so the entire amount of the refreservation will need 2186 * to be free). We will immediately destroy the clone, freeing 2187 * this space, but the freeing happens over many txg's. 2188 */ 2189 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 2190 dsl_dataset_phys(ds)->ds_unique_bytes); 2191 2192 if (unused_refres_delta > 0 && 2193 unused_refres_delta > 2194 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 2195 dsl_dataset_rele(ds, FTAG); 2196 return (SET_ERROR(ENOSPC)); 2197 } 2198 2199 dsl_dataset_rele(ds, FTAG); 2200 return (0); 2201 } 2202 2203 static void 2204 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 2205 { 2206 dsl_dataset_rollback_arg_t *ddra = arg; 2207 dsl_pool_t *dp = dmu_tx_pool(tx); 2208 dsl_dataset_t *ds, *clone; 2209 uint64_t cloneobj; 2210 char namebuf[ZFS_MAXNAMELEN]; 2211 2212 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 2213 2214 dsl_dataset_name(ds->ds_prev, namebuf); 2215 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 2216 2217 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 2218 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 2219 2220 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 2221 2222 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 2223 dsl_dataset_zero_zil(ds, tx); 2224 2225 dsl_destroy_head_sync_impl(clone, tx); 2226 2227 dsl_dataset_rele(clone, FTAG); 2228 dsl_dataset_rele(ds, FTAG); 2229 } 2230 2231 /* 2232 * Rolls back the given filesystem or volume to the most recent snapshot. 2233 * The name of the most recent snapshot will be returned under key "target" 2234 * in the result nvlist. 2235 * 2236 * If owner != NULL: 2237 * - The existing dataset MUST be owned by the specified owner at entry 2238 * - Upon return, dataset will still be held by the same owner, whether we 2239 * succeed or not. 2240 * 2241 * This mode is required any time the existing filesystem is mounted. See 2242 * notes above zfs_suspend_fs() for further details. 2243 */ 2244 int 2245 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result) 2246 { 2247 dsl_dataset_rollback_arg_t ddra; 2248 2249 ddra.ddra_fsname = fsname; 2250 ddra.ddra_owner = owner; 2251 ddra.ddra_result = result; 2252 2253 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 2254 dsl_dataset_rollback_sync, &ddra, 2255 1, ZFS_SPACE_CHECK_RESERVED)); 2256 } 2257 2258 struct promotenode { 2259 list_node_t link; 2260 dsl_dataset_t *ds; 2261 }; 2262 2263 typedef struct dsl_dataset_promote_arg { 2264 const char *ddpa_clonename; 2265 dsl_dataset_t *ddpa_clone; 2266 list_t shared_snaps, origin_snaps, clone_snaps; 2267 dsl_dataset_t *origin_origin; /* origin of the origin */ 2268 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2269 char *err_ds; 2270 cred_t *cr; 2271 } dsl_dataset_promote_arg_t; 2272 2273 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2274 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 2275 void *tag); 2276 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 2277 2278 static int 2279 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 2280 { 2281 dsl_dataset_promote_arg_t *ddpa = arg; 2282 dsl_pool_t *dp = dmu_tx_pool(tx); 2283 dsl_dataset_t *hds; 2284 struct promotenode *snap; 2285 dsl_dataset_t *origin_ds; 2286 int err; 2287 uint64_t unused; 2288 uint64_t ss_mv_cnt; 2289 size_t max_snap_len; 2290 2291 err = promote_hold(ddpa, dp, FTAG); 2292 if (err != 0) 2293 return (err); 2294 2295 hds = ddpa->ddpa_clone; 2296 max_snap_len = MAXNAMELEN - strlen(ddpa->ddpa_clonename) - 1; 2297 2298 if (dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE) { 2299 promote_rele(ddpa, FTAG); 2300 return (SET_ERROR(EXDEV)); 2301 } 2302 2303 /* 2304 * Compute and check the amount of space to transfer. Since this is 2305 * so expensive, don't do the preliminary check. 2306 */ 2307 if (!dmu_tx_is_syncing(tx)) { 2308 promote_rele(ddpa, FTAG); 2309 return (0); 2310 } 2311 2312 snap = list_head(&ddpa->shared_snaps); 2313 origin_ds = snap->ds; 2314 2315 /* compute origin's new unique space */ 2316 snap = list_tail(&ddpa->clone_snaps); 2317 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2318 origin_ds->ds_object); 2319 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2320 dsl_dataset_phys(origin_ds)->ds_prev_snap_txg, UINT64_MAX, 2321 &ddpa->unique, &unused, &unused); 2322 2323 /* 2324 * Walk the snapshots that we are moving 2325 * 2326 * Compute space to transfer. Consider the incremental changes 2327 * to used by each snapshot: 2328 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2329 * So each snapshot gave birth to: 2330 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2331 * So a sequence would look like: 2332 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2333 * Which simplifies to: 2334 * uN + kN + kN-1 + ... + k1 + k0 2335 * Note however, if we stop before we reach the ORIGIN we get: 2336 * uN + kN + kN-1 + ... + kM - uM-1 2337 */ 2338 ss_mv_cnt = 0; 2339 ddpa->used = dsl_dataset_phys(origin_ds)->ds_referenced_bytes; 2340 ddpa->comp = dsl_dataset_phys(origin_ds)->ds_compressed_bytes; 2341 ddpa->uncomp = dsl_dataset_phys(origin_ds)->ds_uncompressed_bytes; 2342 for (snap = list_head(&ddpa->shared_snaps); snap; 2343 snap = list_next(&ddpa->shared_snaps, snap)) { 2344 uint64_t val, dlused, dlcomp, dluncomp; 2345 dsl_dataset_t *ds = snap->ds; 2346 2347 ss_mv_cnt++; 2348 2349 /* 2350 * If there are long holds, we won't be able to evict 2351 * the objset. 2352 */ 2353 if (dsl_dataset_long_held(ds)) { 2354 err = SET_ERROR(EBUSY); 2355 goto out; 2356 } 2357 2358 /* Check that the snapshot name does not conflict */ 2359 VERIFY0(dsl_dataset_get_snapname(ds)); 2360 if (strlen(ds->ds_snapname) >= max_snap_len) { 2361 err = SET_ERROR(ENAMETOOLONG); 2362 goto out; 2363 } 2364 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2365 if (err == 0) { 2366 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname); 2367 err = SET_ERROR(EEXIST); 2368 goto out; 2369 } 2370 if (err != ENOENT) 2371 goto out; 2372 2373 /* The very first snapshot does not have a deadlist */ 2374 if (dsl_dataset_phys(ds)->ds_prev_snap_obj == 0) 2375 continue; 2376 2377 dsl_deadlist_space(&ds->ds_deadlist, 2378 &dlused, &dlcomp, &dluncomp); 2379 ddpa->used += dlused; 2380 ddpa->comp += dlcomp; 2381 ddpa->uncomp += dluncomp; 2382 } 2383 2384 /* 2385 * If we are a clone of a clone then we never reached ORIGIN, 2386 * so we need to subtract out the clone origin's used space. 2387 */ 2388 if (ddpa->origin_origin) { 2389 ddpa->used -= 2390 dsl_dataset_phys(ddpa->origin_origin)->ds_referenced_bytes; 2391 ddpa->comp -= 2392 dsl_dataset_phys(ddpa->origin_origin)->ds_compressed_bytes; 2393 ddpa->uncomp -= 2394 dsl_dataset_phys(ddpa->origin_origin)-> 2395 ds_uncompressed_bytes; 2396 } 2397 2398 /* Check that there is enough space and limit headroom here */ 2399 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2400 0, ss_mv_cnt, ddpa->used, ddpa->cr); 2401 if (err != 0) 2402 goto out; 2403 2404 /* 2405 * Compute the amounts of space that will be used by snapshots 2406 * after the promotion (for both origin and clone). For each, 2407 * it is the amount of space that will be on all of their 2408 * deadlists (that was not born before their new origin). 2409 */ 2410 if (dsl_dir_phys(hds->ds_dir)->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2411 uint64_t space; 2412 2413 /* 2414 * Note, typically this will not be a clone of a clone, 2415 * so dd_origin_txg will be < TXG_INITIAL, so 2416 * these snaplist_space() -> dsl_deadlist_space_range() 2417 * calls will be fast because they do not have to 2418 * iterate over all bps. 2419 */ 2420 snap = list_head(&ddpa->origin_snaps); 2421 err = snaplist_space(&ddpa->shared_snaps, 2422 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 2423 if (err != 0) 2424 goto out; 2425 2426 err = snaplist_space(&ddpa->clone_snaps, 2427 snap->ds->ds_dir->dd_origin_txg, &space); 2428 if (err != 0) 2429 goto out; 2430 ddpa->cloneusedsnap += space; 2431 } 2432 if (dsl_dir_phys(origin_ds->ds_dir)->dd_flags & 2433 DD_FLAG_USED_BREAKDOWN) { 2434 err = snaplist_space(&ddpa->origin_snaps, 2435 dsl_dataset_phys(origin_ds)->ds_creation_txg, 2436 &ddpa->originusedsnap); 2437 if (err != 0) 2438 goto out; 2439 } 2440 2441 out: 2442 promote_rele(ddpa, FTAG); 2443 return (err); 2444 } 2445 2446 static void 2447 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2448 { 2449 dsl_dataset_promote_arg_t *ddpa = arg; 2450 dsl_pool_t *dp = dmu_tx_pool(tx); 2451 dsl_dataset_t *hds; 2452 struct promotenode *snap; 2453 dsl_dataset_t *origin_ds; 2454 dsl_dataset_t *origin_head; 2455 dsl_dir_t *dd; 2456 dsl_dir_t *odd = NULL; 2457 uint64_t oldnext_obj; 2458 int64_t delta; 2459 2460 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2461 hds = ddpa->ddpa_clone; 2462 2463 ASSERT0(dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE); 2464 2465 snap = list_head(&ddpa->shared_snaps); 2466 origin_ds = snap->ds; 2467 dd = hds->ds_dir; 2468 2469 snap = list_head(&ddpa->origin_snaps); 2470 origin_head = snap->ds; 2471 2472 /* 2473 * We need to explicitly open odd, since origin_ds's dd will be 2474 * changing. 2475 */ 2476 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2477 NULL, FTAG, &odd)); 2478 2479 /* change origin's next snap */ 2480 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2481 oldnext_obj = dsl_dataset_phys(origin_ds)->ds_next_snap_obj; 2482 snap = list_tail(&ddpa->clone_snaps); 2483 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2484 origin_ds->ds_object); 2485 dsl_dataset_phys(origin_ds)->ds_next_snap_obj = snap->ds->ds_object; 2486 2487 /* change the origin's next clone */ 2488 if (dsl_dataset_phys(origin_ds)->ds_next_clones_obj) { 2489 dsl_dataset_remove_from_next_clones(origin_ds, 2490 snap->ds->ds_object, tx); 2491 VERIFY0(zap_add_int(dp->dp_meta_objset, 2492 dsl_dataset_phys(origin_ds)->ds_next_clones_obj, 2493 oldnext_obj, tx)); 2494 } 2495 2496 /* change origin */ 2497 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2498 ASSERT3U(dsl_dir_phys(dd)->dd_origin_obj, ==, origin_ds->ds_object); 2499 dsl_dir_phys(dd)->dd_origin_obj = dsl_dir_phys(odd)->dd_origin_obj; 2500 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2501 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2502 dsl_dir_phys(odd)->dd_origin_obj = origin_ds->ds_object; 2503 origin_head->ds_dir->dd_origin_txg = 2504 dsl_dataset_phys(origin_ds)->ds_creation_txg; 2505 2506 /* change dd_clone entries */ 2507 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2508 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2509 dsl_dir_phys(odd)->dd_clones, hds->ds_object, tx)); 2510 VERIFY0(zap_add_int(dp->dp_meta_objset, 2511 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2512 hds->ds_object, tx)); 2513 2514 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2515 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2516 origin_head->ds_object, tx)); 2517 if (dsl_dir_phys(dd)->dd_clones == 0) { 2518 dsl_dir_phys(dd)->dd_clones = 2519 zap_create(dp->dp_meta_objset, DMU_OT_DSL_CLONES, 2520 DMU_OT_NONE, 0, tx); 2521 } 2522 VERIFY0(zap_add_int(dp->dp_meta_objset, 2523 dsl_dir_phys(dd)->dd_clones, origin_head->ds_object, tx)); 2524 } 2525 2526 /* move snapshots to this dir */ 2527 for (snap = list_head(&ddpa->shared_snaps); snap; 2528 snap = list_next(&ddpa->shared_snaps, snap)) { 2529 dsl_dataset_t *ds = snap->ds; 2530 2531 /* 2532 * Property callbacks are registered to a particular 2533 * dsl_dir. Since ours is changing, evict the objset 2534 * so that they will be unregistered from the old dsl_dir. 2535 */ 2536 if (ds->ds_objset) { 2537 dmu_objset_evict(ds->ds_objset); 2538 ds->ds_objset = NULL; 2539 } 2540 2541 /* move snap name entry */ 2542 VERIFY0(dsl_dataset_get_snapname(ds)); 2543 VERIFY0(dsl_dataset_snap_remove(origin_head, 2544 ds->ds_snapname, tx, B_TRUE)); 2545 VERIFY0(zap_add(dp->dp_meta_objset, 2546 dsl_dataset_phys(hds)->ds_snapnames_zapobj, ds->ds_snapname, 2547 8, 1, &ds->ds_object, tx)); 2548 dsl_fs_ss_count_adjust(hds->ds_dir, 1, 2549 DD_FIELD_SNAPSHOT_COUNT, tx); 2550 2551 /* change containing dsl_dir */ 2552 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2553 ASSERT3U(dsl_dataset_phys(ds)->ds_dir_obj, ==, odd->dd_object); 2554 dsl_dataset_phys(ds)->ds_dir_obj = dd->dd_object; 2555 ASSERT3P(ds->ds_dir, ==, odd); 2556 dsl_dir_rele(ds->ds_dir, ds); 2557 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2558 NULL, ds, &ds->ds_dir)); 2559 2560 /* move any clone references */ 2561 if (dsl_dataset_phys(ds)->ds_next_clones_obj && 2562 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2563 zap_cursor_t zc; 2564 zap_attribute_t za; 2565 2566 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2567 dsl_dataset_phys(ds)->ds_next_clones_obj); 2568 zap_cursor_retrieve(&zc, &za) == 0; 2569 zap_cursor_advance(&zc)) { 2570 dsl_dataset_t *cnds; 2571 uint64_t o; 2572 2573 if (za.za_first_integer == oldnext_obj) { 2574 /* 2575 * We've already moved the 2576 * origin's reference. 2577 */ 2578 continue; 2579 } 2580 2581 VERIFY0(dsl_dataset_hold_obj(dp, 2582 za.za_first_integer, FTAG, &cnds)); 2583 o = dsl_dir_phys(cnds->ds_dir)-> 2584 dd_head_dataset_obj; 2585 2586 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2587 dsl_dir_phys(odd)->dd_clones, o, tx)); 2588 VERIFY0(zap_add_int(dp->dp_meta_objset, 2589 dsl_dir_phys(dd)->dd_clones, o, tx)); 2590 dsl_dataset_rele(cnds, FTAG); 2591 } 2592 zap_cursor_fini(&zc); 2593 } 2594 2595 ASSERT(!dsl_prop_hascb(ds)); 2596 } 2597 2598 /* 2599 * Change space accounting. 2600 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2601 * both be valid, or both be 0 (resulting in delta == 0). This 2602 * is true for each of {clone,origin} independently. 2603 */ 2604 2605 delta = ddpa->cloneusedsnap - 2606 dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_SNAP]; 2607 ASSERT3S(delta, >=, 0); 2608 ASSERT3U(ddpa->used, >=, delta); 2609 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2610 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2611 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2612 2613 delta = ddpa->originusedsnap - 2614 dsl_dir_phys(odd)->dd_used_breakdown[DD_USED_SNAP]; 2615 ASSERT3S(delta, <=, 0); 2616 ASSERT3U(ddpa->used, >=, -delta); 2617 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2618 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2619 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2620 2621 dsl_dataset_phys(origin_ds)->ds_unique_bytes = ddpa->unique; 2622 2623 /* log history record */ 2624 spa_history_log_internal_ds(hds, "promote", tx, ""); 2625 2626 dsl_dir_rele(odd, FTAG); 2627 promote_rele(ddpa, FTAG); 2628 } 2629 2630 /* 2631 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2632 * (exclusive) and last_obj (inclusive). The list will be in reverse 2633 * order (last_obj will be the list_head()). If first_obj == 0, do all 2634 * snapshots back to this dataset's origin. 2635 */ 2636 static int 2637 snaplist_make(dsl_pool_t *dp, 2638 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2639 { 2640 uint64_t obj = last_obj; 2641 2642 list_create(l, sizeof (struct promotenode), 2643 offsetof(struct promotenode, link)); 2644 2645 while (obj != first_obj) { 2646 dsl_dataset_t *ds; 2647 struct promotenode *snap; 2648 int err; 2649 2650 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 2651 ASSERT(err != ENOENT); 2652 if (err != 0) 2653 return (err); 2654 2655 if (first_obj == 0) 2656 first_obj = dsl_dir_phys(ds->ds_dir)->dd_origin_obj; 2657 2658 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 2659 snap->ds = ds; 2660 list_insert_tail(l, snap); 2661 obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 2662 } 2663 2664 return (0); 2665 } 2666 2667 static int 2668 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2669 { 2670 struct promotenode *snap; 2671 2672 *spacep = 0; 2673 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2674 uint64_t used, comp, uncomp; 2675 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2676 mintxg, UINT64_MAX, &used, &comp, &uncomp); 2677 *spacep += used; 2678 } 2679 return (0); 2680 } 2681 2682 static void 2683 snaplist_destroy(list_t *l, void *tag) 2684 { 2685 struct promotenode *snap; 2686 2687 if (l == NULL || !list_link_active(&l->list_head)) 2688 return; 2689 2690 while ((snap = list_tail(l)) != NULL) { 2691 list_remove(l, snap); 2692 dsl_dataset_rele(snap->ds, tag); 2693 kmem_free(snap, sizeof (*snap)); 2694 } 2695 list_destroy(l); 2696 } 2697 2698 static int 2699 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 2700 { 2701 int error; 2702 dsl_dir_t *dd; 2703 struct promotenode *snap; 2704 2705 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 2706 &ddpa->ddpa_clone); 2707 if (error != 0) 2708 return (error); 2709 dd = ddpa->ddpa_clone->ds_dir; 2710 2711 if (ddpa->ddpa_clone->ds_is_snapshot || 2712 !dsl_dir_is_clone(dd)) { 2713 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2714 return (SET_ERROR(EINVAL)); 2715 } 2716 2717 error = snaplist_make(dp, 0, dsl_dir_phys(dd)->dd_origin_obj, 2718 &ddpa->shared_snaps, tag); 2719 if (error != 0) 2720 goto out; 2721 2722 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 2723 &ddpa->clone_snaps, tag); 2724 if (error != 0) 2725 goto out; 2726 2727 snap = list_head(&ddpa->shared_snaps); 2728 ASSERT3U(snap->ds->ds_object, ==, dsl_dir_phys(dd)->dd_origin_obj); 2729 error = snaplist_make(dp, dsl_dir_phys(dd)->dd_origin_obj, 2730 dsl_dir_phys(snap->ds->ds_dir)->dd_head_dataset_obj, 2731 &ddpa->origin_snaps, tag); 2732 if (error != 0) 2733 goto out; 2734 2735 if (dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj != 0) { 2736 error = dsl_dataset_hold_obj(dp, 2737 dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj, 2738 tag, &ddpa->origin_origin); 2739 if (error != 0) 2740 goto out; 2741 } 2742 out: 2743 if (error != 0) 2744 promote_rele(ddpa, tag); 2745 return (error); 2746 } 2747 2748 static void 2749 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 2750 { 2751 snaplist_destroy(&ddpa->shared_snaps, tag); 2752 snaplist_destroy(&ddpa->clone_snaps, tag); 2753 snaplist_destroy(&ddpa->origin_snaps, tag); 2754 if (ddpa->origin_origin != NULL) 2755 dsl_dataset_rele(ddpa->origin_origin, tag); 2756 dsl_dataset_rele(ddpa->ddpa_clone, tag); 2757 } 2758 2759 /* 2760 * Promote a clone. 2761 * 2762 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 2763 * in with the name. (It must be at least MAXNAMELEN bytes long.) 2764 */ 2765 int 2766 dsl_dataset_promote(const char *name, char *conflsnap) 2767 { 2768 dsl_dataset_promote_arg_t ddpa = { 0 }; 2769 uint64_t numsnaps; 2770 int error; 2771 objset_t *os; 2772 2773 /* 2774 * We will modify space proportional to the number of 2775 * snapshots. Compute numsnaps. 2776 */ 2777 error = dmu_objset_hold(name, FTAG, &os); 2778 if (error != 0) 2779 return (error); 2780 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 2781 dsl_dataset_phys(dmu_objset_ds(os))->ds_snapnames_zapobj, 2782 &numsnaps); 2783 dmu_objset_rele(os, FTAG); 2784 if (error != 0) 2785 return (error); 2786 2787 ddpa.ddpa_clonename = name; 2788 ddpa.err_ds = conflsnap; 2789 ddpa.cr = CRED(); 2790 2791 return (dsl_sync_task(name, dsl_dataset_promote_check, 2792 dsl_dataset_promote_sync, &ddpa, 2793 2 + numsnaps, ZFS_SPACE_CHECK_RESERVED)); 2794 } 2795 2796 int 2797 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 2798 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 2799 { 2800 /* 2801 * "slack" factor for received datasets with refquota set on them. 2802 * See the bottom of this function for details on its use. 2803 */ 2804 uint64_t refquota_slack = DMU_MAX_ACCESS * spa_asize_inflation; 2805 int64_t unused_refres_delta; 2806 2807 /* they should both be heads */ 2808 if (clone->ds_is_snapshot || 2809 origin_head->ds_is_snapshot) 2810 return (SET_ERROR(EINVAL)); 2811 2812 /* if we are not forcing, the branch point should be just before them */ 2813 if (!force && clone->ds_prev != origin_head->ds_prev) 2814 return (SET_ERROR(EINVAL)); 2815 2816 /* clone should be the clone (unless they are unrelated) */ 2817 if (clone->ds_prev != NULL && 2818 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 2819 origin_head->ds_dir != clone->ds_prev->ds_dir) 2820 return (SET_ERROR(EINVAL)); 2821 2822 /* the clone should be a child of the origin */ 2823 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 2824 return (SET_ERROR(EINVAL)); 2825 2826 /* origin_head shouldn't be modified unless 'force' */ 2827 if (!force && 2828 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 2829 return (SET_ERROR(ETXTBSY)); 2830 2831 /* origin_head should have no long holds (e.g. is not mounted) */ 2832 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 2833 return (SET_ERROR(EBUSY)); 2834 2835 /* check amount of any unconsumed refreservation */ 2836 unused_refres_delta = 2837 (int64_t)MIN(origin_head->ds_reserved, 2838 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 2839 (int64_t)MIN(origin_head->ds_reserved, 2840 dsl_dataset_phys(clone)->ds_unique_bytes); 2841 2842 if (unused_refres_delta > 0 && 2843 unused_refres_delta > 2844 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 2845 return (SET_ERROR(ENOSPC)); 2846 2847 /* 2848 * The clone can't be too much over the head's refquota. 2849 * 2850 * To ensure that the entire refquota can be used, we allow one 2851 * transaction to exceed the the refquota. Therefore, this check 2852 * needs to also allow for the space referenced to be more than the 2853 * refquota. The maximum amount of space that one transaction can use 2854 * on disk is DMU_MAX_ACCESS * spa_asize_inflation. Allowing this 2855 * overage ensures that we are able to receive a filesystem that 2856 * exceeds the refquota on the source system. 2857 * 2858 * So that overage is the refquota_slack we use below. 2859 */ 2860 if (origin_head->ds_quota != 0 && 2861 dsl_dataset_phys(clone)->ds_referenced_bytes > 2862 origin_head->ds_quota + refquota_slack) 2863 return (SET_ERROR(EDQUOT)); 2864 2865 return (0); 2866 } 2867 2868 void 2869 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 2870 dsl_dataset_t *origin_head, dmu_tx_t *tx) 2871 { 2872 dsl_pool_t *dp = dmu_tx_pool(tx); 2873 int64_t unused_refres_delta; 2874 2875 ASSERT(clone->ds_reserved == 0); 2876 /* 2877 * NOTE: On DEBUG kernels there could be a race between this and 2878 * the check function if spa_asize_inflation is adjusted... 2879 */ 2880 ASSERT(origin_head->ds_quota == 0 || 2881 dsl_dataset_phys(clone)->ds_unique_bytes <= origin_head->ds_quota + 2882 DMU_MAX_ACCESS * spa_asize_inflation); 2883 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 2884 2885 /* 2886 * Swap per-dataset feature flags. 2887 */ 2888 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 2889 if (!(spa_feature_table[f].fi_flags & 2890 ZFEATURE_FLAG_PER_DATASET)) { 2891 ASSERT(!clone->ds_feature_inuse[f]); 2892 ASSERT(!origin_head->ds_feature_inuse[f]); 2893 continue; 2894 } 2895 2896 boolean_t clone_inuse = clone->ds_feature_inuse[f]; 2897 boolean_t origin_head_inuse = origin_head->ds_feature_inuse[f]; 2898 2899 if (clone_inuse) { 2900 dsl_dataset_deactivate_feature(clone->ds_object, f, tx); 2901 clone->ds_feature_inuse[f] = B_FALSE; 2902 } 2903 if (origin_head_inuse) { 2904 dsl_dataset_deactivate_feature(origin_head->ds_object, 2905 f, tx); 2906 origin_head->ds_feature_inuse[f] = B_FALSE; 2907 } 2908 if (clone_inuse) { 2909 dsl_dataset_activate_feature(origin_head->ds_object, 2910 f, tx); 2911 origin_head->ds_feature_inuse[f] = B_TRUE; 2912 } 2913 if (origin_head_inuse) { 2914 dsl_dataset_activate_feature(clone->ds_object, f, tx); 2915 clone->ds_feature_inuse[f] = B_TRUE; 2916 } 2917 } 2918 2919 dmu_buf_will_dirty(clone->ds_dbuf, tx); 2920 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 2921 2922 if (clone->ds_objset != NULL) { 2923 dmu_objset_evict(clone->ds_objset); 2924 clone->ds_objset = NULL; 2925 } 2926 2927 if (origin_head->ds_objset != NULL) { 2928 dmu_objset_evict(origin_head->ds_objset); 2929 origin_head->ds_objset = NULL; 2930 } 2931 2932 unused_refres_delta = 2933 (int64_t)MIN(origin_head->ds_reserved, 2934 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 2935 (int64_t)MIN(origin_head->ds_reserved, 2936 dsl_dataset_phys(clone)->ds_unique_bytes); 2937 2938 /* 2939 * Reset origin's unique bytes, if it exists. 2940 */ 2941 if (clone->ds_prev) { 2942 dsl_dataset_t *origin = clone->ds_prev; 2943 uint64_t comp, uncomp; 2944 2945 dmu_buf_will_dirty(origin->ds_dbuf, tx); 2946 dsl_deadlist_space_range(&clone->ds_deadlist, 2947 dsl_dataset_phys(origin)->ds_prev_snap_txg, UINT64_MAX, 2948 &dsl_dataset_phys(origin)->ds_unique_bytes, &comp, &uncomp); 2949 } 2950 2951 /* swap blkptrs */ 2952 { 2953 blkptr_t tmp; 2954 tmp = dsl_dataset_phys(origin_head)->ds_bp; 2955 dsl_dataset_phys(origin_head)->ds_bp = 2956 dsl_dataset_phys(clone)->ds_bp; 2957 dsl_dataset_phys(clone)->ds_bp = tmp; 2958 } 2959 2960 /* set dd_*_bytes */ 2961 { 2962 int64_t dused, dcomp, duncomp; 2963 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2964 uint64_t odl_used, odl_comp, odl_uncomp; 2965 2966 ASSERT3U(dsl_dir_phys(clone->ds_dir)-> 2967 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2968 2969 dsl_deadlist_space(&clone->ds_deadlist, 2970 &cdl_used, &cdl_comp, &cdl_uncomp); 2971 dsl_deadlist_space(&origin_head->ds_deadlist, 2972 &odl_used, &odl_comp, &odl_uncomp); 2973 2974 dused = dsl_dataset_phys(clone)->ds_referenced_bytes + 2975 cdl_used - 2976 (dsl_dataset_phys(origin_head)->ds_referenced_bytes + 2977 odl_used); 2978 dcomp = dsl_dataset_phys(clone)->ds_compressed_bytes + 2979 cdl_comp - 2980 (dsl_dataset_phys(origin_head)->ds_compressed_bytes + 2981 odl_comp); 2982 duncomp = dsl_dataset_phys(clone)->ds_uncompressed_bytes + 2983 cdl_uncomp - 2984 (dsl_dataset_phys(origin_head)->ds_uncompressed_bytes + 2985 odl_uncomp); 2986 2987 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 2988 dused, dcomp, duncomp, tx); 2989 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 2990 -dused, -dcomp, -duncomp, tx); 2991 2992 /* 2993 * The difference in the space used by snapshots is the 2994 * difference in snapshot space due to the head's 2995 * deadlist (since that's the only thing that's 2996 * changing that affects the snapused). 2997 */ 2998 dsl_deadlist_space_range(&clone->ds_deadlist, 2999 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3000 &cdl_used, &cdl_comp, &cdl_uncomp); 3001 dsl_deadlist_space_range(&origin_head->ds_deadlist, 3002 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3003 &odl_used, &odl_comp, &odl_uncomp); 3004 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 3005 DD_USED_HEAD, DD_USED_SNAP, tx); 3006 } 3007 3008 /* swap ds_*_bytes */ 3009 SWITCH64(dsl_dataset_phys(origin_head)->ds_referenced_bytes, 3010 dsl_dataset_phys(clone)->ds_referenced_bytes); 3011 SWITCH64(dsl_dataset_phys(origin_head)->ds_compressed_bytes, 3012 dsl_dataset_phys(clone)->ds_compressed_bytes); 3013 SWITCH64(dsl_dataset_phys(origin_head)->ds_uncompressed_bytes, 3014 dsl_dataset_phys(clone)->ds_uncompressed_bytes); 3015 SWITCH64(dsl_dataset_phys(origin_head)->ds_unique_bytes, 3016 dsl_dataset_phys(clone)->ds_unique_bytes); 3017 3018 /* apply any parent delta for change in unconsumed refreservation */ 3019 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 3020 unused_refres_delta, 0, 0, tx); 3021 3022 /* 3023 * Swap deadlists. 3024 */ 3025 dsl_deadlist_close(&clone->ds_deadlist); 3026 dsl_deadlist_close(&origin_head->ds_deadlist); 3027 SWITCH64(dsl_dataset_phys(origin_head)->ds_deadlist_obj, 3028 dsl_dataset_phys(clone)->ds_deadlist_obj); 3029 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 3030 dsl_dataset_phys(clone)->ds_deadlist_obj); 3031 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 3032 dsl_dataset_phys(origin_head)->ds_deadlist_obj); 3033 3034 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 3035 3036 spa_history_log_internal_ds(clone, "clone swap", tx, 3037 "parent=%s", origin_head->ds_dir->dd_myname); 3038 } 3039 3040 /* 3041 * Given a pool name and a dataset object number in that pool, 3042 * return the name of that dataset. 3043 */ 3044 int 3045 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 3046 { 3047 dsl_pool_t *dp; 3048 dsl_dataset_t *ds; 3049 int error; 3050 3051 error = dsl_pool_hold(pname, FTAG, &dp); 3052 if (error != 0) 3053 return (error); 3054 3055 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 3056 if (error == 0) { 3057 dsl_dataset_name(ds, buf); 3058 dsl_dataset_rele(ds, FTAG); 3059 } 3060 dsl_pool_rele(dp, FTAG); 3061 3062 return (error); 3063 } 3064 3065 int 3066 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 3067 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 3068 { 3069 int error = 0; 3070 3071 ASSERT3S(asize, >, 0); 3072 3073 /* 3074 * *ref_rsrv is the portion of asize that will come from any 3075 * unconsumed refreservation space. 3076 */ 3077 *ref_rsrv = 0; 3078 3079 mutex_enter(&ds->ds_lock); 3080 /* 3081 * Make a space adjustment for reserved bytes. 3082 */ 3083 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) { 3084 ASSERT3U(*used, >=, 3085 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3086 *used -= 3087 (ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3088 *ref_rsrv = 3089 asize - MIN(asize, parent_delta(ds, asize + inflight)); 3090 } 3091 3092 if (!check_quota || ds->ds_quota == 0) { 3093 mutex_exit(&ds->ds_lock); 3094 return (0); 3095 } 3096 /* 3097 * If they are requesting more space, and our current estimate 3098 * is over quota, they get to try again unless the actual 3099 * on-disk is over quota and there are no pending changes (which 3100 * may free up space for us). 3101 */ 3102 if (dsl_dataset_phys(ds)->ds_referenced_bytes + inflight >= 3103 ds->ds_quota) { 3104 if (inflight > 0 || 3105 dsl_dataset_phys(ds)->ds_referenced_bytes < ds->ds_quota) 3106 error = SET_ERROR(ERESTART); 3107 else 3108 error = SET_ERROR(EDQUOT); 3109 } 3110 mutex_exit(&ds->ds_lock); 3111 3112 return (error); 3113 } 3114 3115 typedef struct dsl_dataset_set_qr_arg { 3116 const char *ddsqra_name; 3117 zprop_source_t ddsqra_source; 3118 uint64_t ddsqra_value; 3119 } dsl_dataset_set_qr_arg_t; 3120 3121 3122 /* ARGSUSED */ 3123 static int 3124 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 3125 { 3126 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3127 dsl_pool_t *dp = dmu_tx_pool(tx); 3128 dsl_dataset_t *ds; 3129 int error; 3130 uint64_t newval; 3131 3132 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 3133 return (SET_ERROR(ENOTSUP)); 3134 3135 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3136 if (error != 0) 3137 return (error); 3138 3139 if (ds->ds_is_snapshot) { 3140 dsl_dataset_rele(ds, FTAG); 3141 return (SET_ERROR(EINVAL)); 3142 } 3143 3144 error = dsl_prop_predict(ds->ds_dir, 3145 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3146 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3147 if (error != 0) { 3148 dsl_dataset_rele(ds, FTAG); 3149 return (error); 3150 } 3151 3152 if (newval == 0) { 3153 dsl_dataset_rele(ds, FTAG); 3154 return (0); 3155 } 3156 3157 if (newval < dsl_dataset_phys(ds)->ds_referenced_bytes || 3158 newval < ds->ds_reserved) { 3159 dsl_dataset_rele(ds, FTAG); 3160 return (SET_ERROR(ENOSPC)); 3161 } 3162 3163 dsl_dataset_rele(ds, FTAG); 3164 return (0); 3165 } 3166 3167 static void 3168 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 3169 { 3170 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3171 dsl_pool_t *dp = dmu_tx_pool(tx); 3172 dsl_dataset_t *ds; 3173 uint64_t newval; 3174 3175 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3176 3177 dsl_prop_set_sync_impl(ds, 3178 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3179 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 3180 &ddsqra->ddsqra_value, tx); 3181 3182 VERIFY0(dsl_prop_get_int_ds(ds, 3183 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 3184 3185 if (ds->ds_quota != newval) { 3186 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3187 ds->ds_quota = newval; 3188 } 3189 dsl_dataset_rele(ds, FTAG); 3190 } 3191 3192 int 3193 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 3194 uint64_t refquota) 3195 { 3196 dsl_dataset_set_qr_arg_t ddsqra; 3197 3198 ddsqra.ddsqra_name = dsname; 3199 ddsqra.ddsqra_source = source; 3200 ddsqra.ddsqra_value = refquota; 3201 3202 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 3203 dsl_dataset_set_refquota_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE)); 3204 } 3205 3206 static int 3207 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 3208 { 3209 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3210 dsl_pool_t *dp = dmu_tx_pool(tx); 3211 dsl_dataset_t *ds; 3212 int error; 3213 uint64_t newval, unique; 3214 3215 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 3216 return (SET_ERROR(ENOTSUP)); 3217 3218 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3219 if (error != 0) 3220 return (error); 3221 3222 if (ds->ds_is_snapshot) { 3223 dsl_dataset_rele(ds, FTAG); 3224 return (SET_ERROR(EINVAL)); 3225 } 3226 3227 error = dsl_prop_predict(ds->ds_dir, 3228 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3229 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3230 if (error != 0) { 3231 dsl_dataset_rele(ds, FTAG); 3232 return (error); 3233 } 3234 3235 /* 3236 * If we are doing the preliminary check in open context, the 3237 * space estimates may be inaccurate. 3238 */ 3239 if (!dmu_tx_is_syncing(tx)) { 3240 dsl_dataset_rele(ds, FTAG); 3241 return (0); 3242 } 3243 3244 mutex_enter(&ds->ds_lock); 3245 if (!DS_UNIQUE_IS_ACCURATE(ds)) 3246 dsl_dataset_recalc_head_uniq(ds); 3247 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3248 mutex_exit(&ds->ds_lock); 3249 3250 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 3251 uint64_t delta = MAX(unique, newval) - 3252 MAX(unique, ds->ds_reserved); 3253 3254 if (delta > 3255 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 3256 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 3257 dsl_dataset_rele(ds, FTAG); 3258 return (SET_ERROR(ENOSPC)); 3259 } 3260 } 3261 3262 dsl_dataset_rele(ds, FTAG); 3263 return (0); 3264 } 3265 3266 void 3267 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 3268 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 3269 { 3270 uint64_t newval; 3271 uint64_t unique; 3272 int64_t delta; 3273 3274 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3275 source, sizeof (value), 1, &value, tx); 3276 3277 VERIFY0(dsl_prop_get_int_ds(ds, 3278 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 3279 3280 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3281 mutex_enter(&ds->ds_dir->dd_lock); 3282 mutex_enter(&ds->ds_lock); 3283 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 3284 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3285 delta = MAX(0, (int64_t)(newval - unique)) - 3286 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3287 ds->ds_reserved = newval; 3288 mutex_exit(&ds->ds_lock); 3289 3290 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3291 mutex_exit(&ds->ds_dir->dd_lock); 3292 } 3293 3294 static void 3295 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 3296 { 3297 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3298 dsl_pool_t *dp = dmu_tx_pool(tx); 3299 dsl_dataset_t *ds; 3300 3301 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3302 dsl_dataset_set_refreservation_sync_impl(ds, 3303 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 3304 dsl_dataset_rele(ds, FTAG); 3305 } 3306 3307 int 3308 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 3309 uint64_t refreservation) 3310 { 3311 dsl_dataset_set_qr_arg_t ddsqra; 3312 3313 ddsqra.ddsqra_name = dsname; 3314 ddsqra.ddsqra_source = source; 3315 ddsqra.ddsqra_value = refreservation; 3316 3317 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 3318 dsl_dataset_set_refreservation_sync, &ddsqra, 3319 0, ZFS_SPACE_CHECK_NONE)); 3320 } 3321 3322 /* 3323 * Return (in *usedp) the amount of space written in new that is not 3324 * present in oldsnap. New may be a snapshot or the head. Old must be 3325 * a snapshot before new, in new's filesystem (or its origin). If not then 3326 * fail and return EINVAL. 3327 * 3328 * The written space is calculated by considering two components: First, we 3329 * ignore any freed space, and calculate the written as new's used space 3330 * minus old's used space. Next, we add in the amount of space that was freed 3331 * between the two snapshots, thus reducing new's used space relative to old's. 3332 * Specifically, this is the space that was born before old->ds_creation_txg, 3333 * and freed before new (ie. on new's deadlist or a previous deadlist). 3334 * 3335 * space freed [---------------------] 3336 * snapshots ---O-------O--------O-------O------ 3337 * oldsnap new 3338 */ 3339 int 3340 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 3341 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3342 { 3343 int err = 0; 3344 uint64_t snapobj; 3345 dsl_pool_t *dp = new->ds_dir->dd_pool; 3346 3347 ASSERT(dsl_pool_config_held(dp)); 3348 3349 *usedp = 0; 3350 *usedp += dsl_dataset_phys(new)->ds_referenced_bytes; 3351 *usedp -= dsl_dataset_phys(oldsnap)->ds_referenced_bytes; 3352 3353 *compp = 0; 3354 *compp += dsl_dataset_phys(new)->ds_compressed_bytes; 3355 *compp -= dsl_dataset_phys(oldsnap)->ds_compressed_bytes; 3356 3357 *uncompp = 0; 3358 *uncompp += dsl_dataset_phys(new)->ds_uncompressed_bytes; 3359 *uncompp -= dsl_dataset_phys(oldsnap)->ds_uncompressed_bytes; 3360 3361 snapobj = new->ds_object; 3362 while (snapobj != oldsnap->ds_object) { 3363 dsl_dataset_t *snap; 3364 uint64_t used, comp, uncomp; 3365 3366 if (snapobj == new->ds_object) { 3367 snap = new; 3368 } else { 3369 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 3370 if (err != 0) 3371 break; 3372 } 3373 3374 if (dsl_dataset_phys(snap)->ds_prev_snap_txg == 3375 dsl_dataset_phys(oldsnap)->ds_creation_txg) { 3376 /* 3377 * The blocks in the deadlist can not be born after 3378 * ds_prev_snap_txg, so get the whole deadlist space, 3379 * which is more efficient (especially for old-format 3380 * deadlists). Unfortunately the deadlist code 3381 * doesn't have enough information to make this 3382 * optimization itself. 3383 */ 3384 dsl_deadlist_space(&snap->ds_deadlist, 3385 &used, &comp, &uncomp); 3386 } else { 3387 dsl_deadlist_space_range(&snap->ds_deadlist, 3388 0, dsl_dataset_phys(oldsnap)->ds_creation_txg, 3389 &used, &comp, &uncomp); 3390 } 3391 *usedp += used; 3392 *compp += comp; 3393 *uncompp += uncomp; 3394 3395 /* 3396 * If we get to the beginning of the chain of snapshots 3397 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 3398 * was not a snapshot of/before new. 3399 */ 3400 snapobj = dsl_dataset_phys(snap)->ds_prev_snap_obj; 3401 if (snap != new) 3402 dsl_dataset_rele(snap, FTAG); 3403 if (snapobj == 0) { 3404 err = SET_ERROR(EINVAL); 3405 break; 3406 } 3407 3408 } 3409 return (err); 3410 } 3411 3412 /* 3413 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 3414 * lastsnap, and all snapshots in between are deleted. 3415 * 3416 * blocks that would be freed [---------------------------] 3417 * snapshots ---O-------O--------O-------O--------O 3418 * firstsnap lastsnap 3419 * 3420 * This is the set of blocks that were born after the snap before firstsnap, 3421 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 3422 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 3423 * We calculate this by iterating over the relevant deadlists (from the snap 3424 * after lastsnap, backward to the snap after firstsnap), summing up the 3425 * space on the deadlist that was born after the snap before firstsnap. 3426 */ 3427 int 3428 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 3429 dsl_dataset_t *lastsnap, 3430 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3431 { 3432 int err = 0; 3433 uint64_t snapobj; 3434 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 3435 3436 ASSERT(firstsnap->ds_is_snapshot); 3437 ASSERT(lastsnap->ds_is_snapshot); 3438 3439 /* 3440 * Check that the snapshots are in the same dsl_dir, and firstsnap 3441 * is before lastsnap. 3442 */ 3443 if (firstsnap->ds_dir != lastsnap->ds_dir || 3444 dsl_dataset_phys(firstsnap)->ds_creation_txg > 3445 dsl_dataset_phys(lastsnap)->ds_creation_txg) 3446 return (SET_ERROR(EINVAL)); 3447 3448 *usedp = *compp = *uncompp = 0; 3449 3450 snapobj = dsl_dataset_phys(lastsnap)->ds_next_snap_obj; 3451 while (snapobj != firstsnap->ds_object) { 3452 dsl_dataset_t *ds; 3453 uint64_t used, comp, uncomp; 3454 3455 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 3456 if (err != 0) 3457 break; 3458 3459 dsl_deadlist_space_range(&ds->ds_deadlist, 3460 dsl_dataset_phys(firstsnap)->ds_prev_snap_txg, UINT64_MAX, 3461 &used, &comp, &uncomp); 3462 *usedp += used; 3463 *compp += comp; 3464 *uncompp += uncomp; 3465 3466 snapobj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 3467 ASSERT3U(snapobj, !=, 0); 3468 dsl_dataset_rele(ds, FTAG); 3469 } 3470 return (err); 3471 } 3472 3473 /* 3474 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 3475 * For example, they could both be snapshots of the same filesystem, and 3476 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 3477 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 3478 * filesystem. Or 'earlier' could be the origin's origin. 3479 * 3480 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg. 3481 */ 3482 boolean_t 3483 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier, 3484 uint64_t earlier_txg) 3485 { 3486 dsl_pool_t *dp = later->ds_dir->dd_pool; 3487 int error; 3488 boolean_t ret; 3489 3490 ASSERT(dsl_pool_config_held(dp)); 3491 ASSERT(earlier->ds_is_snapshot || earlier_txg != 0); 3492 3493 if (earlier_txg == 0) 3494 earlier_txg = dsl_dataset_phys(earlier)->ds_creation_txg; 3495 3496 if (later->ds_is_snapshot && 3497 earlier_txg >= dsl_dataset_phys(later)->ds_creation_txg) 3498 return (B_FALSE); 3499 3500 if (later->ds_dir == earlier->ds_dir) 3501 return (B_TRUE); 3502 if (!dsl_dir_is_clone(later->ds_dir)) 3503 return (B_FALSE); 3504 3505 if (dsl_dir_phys(later->ds_dir)->dd_origin_obj == earlier->ds_object) 3506 return (B_TRUE); 3507 dsl_dataset_t *origin; 3508 error = dsl_dataset_hold_obj(dp, 3509 dsl_dir_phys(later->ds_dir)->dd_origin_obj, FTAG, &origin); 3510 if (error != 0) 3511 return (B_FALSE); 3512 ret = dsl_dataset_is_before(origin, earlier, earlier_txg); 3513 dsl_dataset_rele(origin, FTAG); 3514 return (ret); 3515 } 3516 3517 void 3518 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx) 3519 { 3520 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 3521 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx); 3522 } 3523 3524 boolean_t 3525 dsl_dataset_is_zapified(dsl_dataset_t *ds) 3526 { 3527 dmu_object_info_t doi; 3528 3529 dmu_object_info_from_db(ds->ds_dbuf, &doi); 3530 return (doi.doi_type == DMU_OTN_ZAP_METADATA); 3531 } 3532 3533 boolean_t 3534 dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds) 3535 { 3536 return (dsl_dataset_is_zapified(ds) && 3537 zap_contains(ds->ds_dir->dd_pool->dp_meta_objset, 3538 ds->ds_object, DS_FIELD_RESUME_TOGUID) == 0); 3539 } 3540