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