1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2011, 2017 by Delphix. All rights reserved. 25 * Copyright (c) 2014, Joyent, Inc. All rights reserved. 26 * Copyright (c) 2014 RackTop Systems. 27 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 28 * Copyright (c) 2014 Integros [integros.com] 29 * Copyright 2016, OmniTI Computer Consulting, Inc. All rights reserved. 30 * Copyright 2017 Nexenta Systems, Inc. 31 */ 32 33 #include <sys/dmu_objset.h> 34 #include <sys/dsl_dataset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_prop.h> 37 #include <sys/dsl_synctask.h> 38 #include <sys/dmu_traverse.h> 39 #include <sys/dmu_impl.h> 40 #include <sys/dmu_tx.h> 41 #include <sys/arc.h> 42 #include <sys/zio.h> 43 #include <sys/zap.h> 44 #include <sys/zfeature.h> 45 #include <sys/unique.h> 46 #include <sys/zfs_context.h> 47 #include <sys/zfs_ioctl.h> 48 #include <sys/spa.h> 49 #include <sys/zfs_znode.h> 50 #include <sys/zfs_onexit.h> 51 #include <sys/zvol.h> 52 #include <sys/dsl_scan.h> 53 #include <sys/dsl_deadlist.h> 54 #include <sys/dsl_destroy.h> 55 #include <sys/dsl_userhold.h> 56 #include <sys/dsl_bookmark.h> 57 #include <sys/dmu_send.h> 58 #include <sys/zio_checksum.h> 59 #include <sys/zio_compress.h> 60 #include <zfs_fletcher.h> 61 62 /* 63 * The SPA supports block sizes up to 16MB. However, very large blocks 64 * can have an impact on i/o latency (e.g. tying up a spinning disk for 65 * ~300ms), and also potentially on the memory allocator. Therefore, 66 * we do not allow the recordsize to be set larger than zfs_max_recordsize 67 * (default 1MB). Larger blocks can be created by changing this tunable, 68 * and pools with larger blocks can always be imported and used, regardless 69 * of this setting. 70 */ 71 int zfs_max_recordsize = 1 * 1024 * 1024; 72 73 #define SWITCH64(x, y) \ 74 { \ 75 uint64_t __tmp = (x); \ 76 (x) = (y); \ 77 (y) = __tmp; \ 78 } 79 80 #define DS_REF_MAX (1ULL << 62) 81 82 extern inline dsl_dataset_phys_t *dsl_dataset_phys(dsl_dataset_t *ds); 83 84 extern int spa_asize_inflation; 85 86 static zil_header_t zero_zil; 87 88 /* 89 * Figure out how much of this delta should be propogated to the dsl_dir 90 * layer. If there's a refreservation, that space has already been 91 * partially accounted for in our ancestors. 92 */ 93 static int64_t 94 parent_delta(dsl_dataset_t *ds, int64_t delta) 95 { 96 dsl_dataset_phys_t *ds_phys; 97 uint64_t old_bytes, new_bytes; 98 99 if (ds->ds_reserved == 0) 100 return (delta); 101 102 ds_phys = dsl_dataset_phys(ds); 103 old_bytes = MAX(ds_phys->ds_unique_bytes, ds->ds_reserved); 104 new_bytes = MAX(ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 105 106 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 107 return (new_bytes - old_bytes); 108 } 109 110 void 111 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) 112 { 113 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 114 int compressed = BP_GET_PSIZE(bp); 115 int uncompressed = BP_GET_UCSIZE(bp); 116 int64_t delta; 117 118 dprintf_bp(bp, "ds=%p", ds); 119 120 ASSERT(dmu_tx_is_syncing(tx)); 121 /* It could have been compressed away to nothing */ 122 if (BP_IS_HOLE(bp)) 123 return; 124 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 125 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp))); 126 if (ds == NULL) { 127 dsl_pool_mos_diduse_space(tx->tx_pool, 128 used, compressed, uncompressed); 129 return; 130 } 131 132 ASSERT3U(bp->blk_birth, >, dsl_dataset_phys(ds)->ds_prev_snap_txg); 133 dmu_buf_will_dirty(ds->ds_dbuf, tx); 134 mutex_enter(&ds->ds_lock); 135 delta = parent_delta(ds, used); 136 dsl_dataset_phys(ds)->ds_referenced_bytes += used; 137 dsl_dataset_phys(ds)->ds_compressed_bytes += compressed; 138 dsl_dataset_phys(ds)->ds_uncompressed_bytes += uncompressed; 139 dsl_dataset_phys(ds)->ds_unique_bytes += used; 140 141 if (BP_GET_LSIZE(bp) > SPA_OLD_MAXBLOCKSIZE) { 142 ds->ds_feature_activation_needed[SPA_FEATURE_LARGE_BLOCKS] = 143 B_TRUE; 144 } 145 146 spa_feature_t f = zio_checksum_to_feature(BP_GET_CHECKSUM(bp)); 147 if (f != SPA_FEATURE_NONE) 148 ds->ds_feature_activation_needed[f] = B_TRUE; 149 150 mutex_exit(&ds->ds_lock); 151 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 152 compressed, uncompressed, tx); 153 dsl_dir_transfer_space(ds->ds_dir, used - delta, 154 DD_USED_REFRSRV, DD_USED_HEAD, tx); 155 } 156 157 int 158 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, 159 boolean_t async) 160 { 161 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp); 162 int compressed = BP_GET_PSIZE(bp); 163 int uncompressed = BP_GET_UCSIZE(bp); 164 165 if (BP_IS_HOLE(bp)) 166 return (0); 167 168 ASSERT(dmu_tx_is_syncing(tx)); 169 ASSERT(bp->blk_birth <= tx->tx_txg); 170 171 if (ds == NULL) { 172 dsl_free(tx->tx_pool, tx->tx_txg, bp); 173 dsl_pool_mos_diduse_space(tx->tx_pool, 174 -used, -compressed, -uncompressed); 175 return (used); 176 } 177 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 178 179 ASSERT(!ds->ds_is_snapshot); 180 dmu_buf_will_dirty(ds->ds_dbuf, tx); 181 182 if (bp->blk_birth > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 183 int64_t delta; 184 185 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); 186 dsl_free(tx->tx_pool, tx->tx_txg, bp); 187 188 mutex_enter(&ds->ds_lock); 189 ASSERT(dsl_dataset_phys(ds)->ds_unique_bytes >= used || 190 !DS_UNIQUE_IS_ACCURATE(ds)); 191 delta = parent_delta(ds, -used); 192 dsl_dataset_phys(ds)->ds_unique_bytes -= used; 193 mutex_exit(&ds->ds_lock); 194 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 195 delta, -compressed, -uncompressed, tx); 196 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 197 DD_USED_REFRSRV, DD_USED_HEAD, tx); 198 } else { 199 dprintf_bp(bp, "putting on dead list: %s", ""); 200 if (async) { 201 /* 202 * We are here as part of zio's write done callback, 203 * which means we're a zio interrupt thread. We can't 204 * call dsl_deadlist_insert() now because it may block 205 * waiting for I/O. Instead, put bp on the deferred 206 * queue and let dsl_pool_sync() finish the job. 207 */ 208 bplist_append(&ds->ds_pending_deadlist, bp); 209 } else { 210 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx); 211 } 212 ASSERT3U(ds->ds_prev->ds_object, ==, 213 dsl_dataset_phys(ds)->ds_prev_snap_obj); 214 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_num_children > 0); 215 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 216 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 217 ds->ds_object && bp->blk_birth > 218 dsl_dataset_phys(ds->ds_prev)->ds_prev_snap_txg) { 219 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 220 mutex_enter(&ds->ds_prev->ds_lock); 221 dsl_dataset_phys(ds->ds_prev)->ds_unique_bytes += used; 222 mutex_exit(&ds->ds_prev->ds_lock); 223 } 224 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) { 225 dsl_dir_transfer_space(ds->ds_dir, used, 226 DD_USED_HEAD, DD_USED_SNAP, tx); 227 } 228 } 229 mutex_enter(&ds->ds_lock); 230 ASSERT3U(dsl_dataset_phys(ds)->ds_referenced_bytes, >=, used); 231 dsl_dataset_phys(ds)->ds_referenced_bytes -= used; 232 ASSERT3U(dsl_dataset_phys(ds)->ds_compressed_bytes, >=, compressed); 233 dsl_dataset_phys(ds)->ds_compressed_bytes -= compressed; 234 ASSERT3U(dsl_dataset_phys(ds)->ds_uncompressed_bytes, >=, uncompressed); 235 dsl_dataset_phys(ds)->ds_uncompressed_bytes -= uncompressed; 236 mutex_exit(&ds->ds_lock); 237 238 return (used); 239 } 240 241 /* 242 * We have to release the fsid syncronously or we risk that a subsequent 243 * mount of the same dataset will fail to unique_insert the fsid. This 244 * failure would manifest itself as the fsid of this dataset changing 245 * between mounts which makes NFS clients quite unhappy. 246 */ 247 static void 248 dsl_dataset_evict_sync(void *dbu) 249 { 250 dsl_dataset_t *ds = dbu; 251 252 ASSERT(ds->ds_owner == NULL); 253 254 unique_remove(ds->ds_fsid_guid); 255 } 256 257 static void 258 dsl_dataset_evict_async(void *dbu) 259 { 260 dsl_dataset_t *ds = dbu; 261 262 ASSERT(ds->ds_owner == NULL); 263 264 ds->ds_dbuf = NULL; 265 266 if (ds->ds_objset != NULL) 267 dmu_objset_evict(ds->ds_objset); 268 269 if (ds->ds_prev) { 270 dsl_dataset_rele(ds->ds_prev, ds); 271 ds->ds_prev = NULL; 272 } 273 274 bplist_destroy(&ds->ds_pending_deadlist); 275 if (ds->ds_deadlist.dl_os != NULL) 276 dsl_deadlist_close(&ds->ds_deadlist); 277 if (ds->ds_dir) 278 dsl_dir_async_rele(ds->ds_dir, ds); 279 280 ASSERT(!list_link_active(&ds->ds_synced_link)); 281 282 list_destroy(&ds->ds_prop_cbs); 283 mutex_destroy(&ds->ds_lock); 284 mutex_destroy(&ds->ds_opening_lock); 285 mutex_destroy(&ds->ds_sendstream_lock); 286 refcount_destroy(&ds->ds_longholds); 287 rrw_destroy(&ds->ds_bp_rwlock); 288 289 kmem_free(ds, sizeof (dsl_dataset_t)); 290 } 291 292 int 293 dsl_dataset_get_snapname(dsl_dataset_t *ds) 294 { 295 dsl_dataset_phys_t *headphys; 296 int err; 297 dmu_buf_t *headdbuf; 298 dsl_pool_t *dp = ds->ds_dir->dd_pool; 299 objset_t *mos = dp->dp_meta_objset; 300 301 if (ds->ds_snapname[0]) 302 return (0); 303 if (dsl_dataset_phys(ds)->ds_next_snap_obj == 0) 304 return (0); 305 306 err = dmu_bonus_hold(mos, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, 307 FTAG, &headdbuf); 308 if (err != 0) 309 return (err); 310 headphys = headdbuf->db_data; 311 err = zap_value_search(dp->dp_meta_objset, 312 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 313 dmu_buf_rele(headdbuf, FTAG); 314 return (err); 315 } 316 317 int 318 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 319 { 320 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 321 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 322 matchtype_t mt = 0; 323 int err; 324 325 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 326 mt = MT_NORMALIZE; 327 328 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 329 value, mt, NULL, 0, NULL); 330 if (err == ENOTSUP && (mt & MT_NORMALIZE)) 331 err = zap_lookup(mos, snapobj, name, 8, 1, value); 332 return (err); 333 } 334 335 int 336 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx, 337 boolean_t adj_cnt) 338 { 339 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 340 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj; 341 matchtype_t mt = 0; 342 int err; 343 344 dsl_dir_snap_cmtime_update(ds->ds_dir); 345 346 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET) 347 mt = MT_NORMALIZE; 348 349 err = zap_remove_norm(mos, snapobj, name, mt, tx); 350 if (err == ENOTSUP && (mt & MT_NORMALIZE)) 351 err = zap_remove(mos, snapobj, name, tx); 352 353 if (err == 0 && adj_cnt) 354 dsl_fs_ss_count_adjust(ds->ds_dir, -1, 355 DD_FIELD_SNAPSHOT_COUNT, tx); 356 357 return (err); 358 } 359 360 boolean_t 361 dsl_dataset_try_add_ref(dsl_pool_t *dp, dsl_dataset_t *ds, void *tag) 362 { 363 dmu_buf_t *dbuf = ds->ds_dbuf; 364 boolean_t result = B_FALSE; 365 366 if (dbuf != NULL && dmu_buf_try_add_ref(dbuf, dp->dp_meta_objset, 367 ds->ds_object, DMU_BONUS_BLKID, tag)) { 368 369 if (ds == dmu_buf_get_user(dbuf)) 370 result = B_TRUE; 371 else 372 dmu_buf_rele(dbuf, tag); 373 } 374 375 return (result); 376 } 377 378 int 379 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 380 dsl_dataset_t **dsp) 381 { 382 objset_t *mos = dp->dp_meta_objset; 383 dmu_buf_t *dbuf; 384 dsl_dataset_t *ds; 385 int err; 386 dmu_object_info_t doi; 387 388 ASSERT(dsl_pool_config_held(dp)); 389 390 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 391 if (err != 0) 392 return (err); 393 394 /* Make sure dsobj has the correct object type. */ 395 dmu_object_info_from_db(dbuf, &doi); 396 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) { 397 dmu_buf_rele(dbuf, tag); 398 return (SET_ERROR(EINVAL)); 399 } 400 401 ds = dmu_buf_get_user(dbuf); 402 if (ds == NULL) { 403 dsl_dataset_t *winner = NULL; 404 405 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 406 ds->ds_dbuf = dbuf; 407 ds->ds_object = dsobj; 408 ds->ds_is_snapshot = dsl_dataset_phys(ds)->ds_num_children != 0; 409 410 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 411 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 412 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL); 413 rrw_init(&ds->ds_bp_rwlock, B_FALSE); 414 refcount_create(&ds->ds_longholds); 415 416 bplist_create(&ds->ds_pending_deadlist); 417 dsl_deadlist_open(&ds->ds_deadlist, 418 mos, dsl_dataset_phys(ds)->ds_deadlist_obj); 419 420 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t), 421 offsetof(dmu_sendarg_t, dsa_link)); 422 423 list_create(&ds->ds_prop_cbs, sizeof (dsl_prop_cb_record_t), 424 offsetof(dsl_prop_cb_record_t, cbr_ds_node)); 425 426 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 427 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 428 if (!(spa_feature_table[f].fi_flags & 429 ZFEATURE_FLAG_PER_DATASET)) 430 continue; 431 err = zap_contains(mos, dsobj, 432 spa_feature_table[f].fi_guid); 433 if (err == 0) { 434 ds->ds_feature_inuse[f] = B_TRUE; 435 } else { 436 ASSERT3U(err, ==, ENOENT); 437 err = 0; 438 } 439 } 440 } 441 442 err = dsl_dir_hold_obj(dp, 443 dsl_dataset_phys(ds)->ds_dir_obj, NULL, ds, &ds->ds_dir); 444 if (err != 0) { 445 mutex_destroy(&ds->ds_lock); 446 mutex_destroy(&ds->ds_opening_lock); 447 mutex_destroy(&ds->ds_sendstream_lock); 448 refcount_destroy(&ds->ds_longholds); 449 bplist_destroy(&ds->ds_pending_deadlist); 450 dsl_deadlist_close(&ds->ds_deadlist); 451 kmem_free(ds, sizeof (dsl_dataset_t)); 452 dmu_buf_rele(dbuf, tag); 453 return (err); 454 } 455 456 if (!ds->ds_is_snapshot) { 457 ds->ds_snapname[0] = '\0'; 458 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 459 err = dsl_dataset_hold_obj(dp, 460 dsl_dataset_phys(ds)->ds_prev_snap_obj, 461 ds, &ds->ds_prev); 462 } 463 if (doi.doi_type == DMU_OTN_ZAP_METADATA) { 464 int zaperr = zap_lookup(mos, ds->ds_object, 465 DS_FIELD_BOOKMARK_NAMES, 466 sizeof (ds->ds_bookmarks), 1, 467 &ds->ds_bookmarks); 468 if (zaperr != ENOENT) 469 VERIFY0(zaperr); 470 } 471 } else { 472 if (zfs_flags & ZFS_DEBUG_SNAPNAMES) 473 err = dsl_dataset_get_snapname(ds); 474 if (err == 0 && 475 dsl_dataset_phys(ds)->ds_userrefs_obj != 0) { 476 err = zap_count( 477 ds->ds_dir->dd_pool->dp_meta_objset, 478 dsl_dataset_phys(ds)->ds_userrefs_obj, 479 &ds->ds_userrefs); 480 } 481 } 482 483 if (err == 0 && !ds->ds_is_snapshot) { 484 err = dsl_prop_get_int_ds(ds, 485 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 486 &ds->ds_reserved); 487 if (err == 0) { 488 err = dsl_prop_get_int_ds(ds, 489 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 490 &ds->ds_quota); 491 } 492 } else { 493 ds->ds_reserved = ds->ds_quota = 0; 494 } 495 496 dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict_sync, 497 dsl_dataset_evict_async, &ds->ds_dbuf); 498 if (err == 0) 499 winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu); 500 501 if (err != 0 || winner != NULL) { 502 bplist_destroy(&ds->ds_pending_deadlist); 503 dsl_deadlist_close(&ds->ds_deadlist); 504 if (ds->ds_prev) 505 dsl_dataset_rele(ds->ds_prev, ds); 506 dsl_dir_rele(ds->ds_dir, ds); 507 mutex_destroy(&ds->ds_lock); 508 mutex_destroy(&ds->ds_opening_lock); 509 mutex_destroy(&ds->ds_sendstream_lock); 510 refcount_destroy(&ds->ds_longholds); 511 kmem_free(ds, sizeof (dsl_dataset_t)); 512 if (err != 0) { 513 dmu_buf_rele(dbuf, tag); 514 return (err); 515 } 516 ds = winner; 517 } else { 518 ds->ds_fsid_guid = 519 unique_insert(dsl_dataset_phys(ds)->ds_fsid_guid); 520 if (ds->ds_fsid_guid != 521 dsl_dataset_phys(ds)->ds_fsid_guid) { 522 zfs_dbgmsg("ds_fsid_guid changed from " 523 "%llx to %llx for pool %s dataset id %llu", 524 (long long) 525 dsl_dataset_phys(ds)->ds_fsid_guid, 526 (long long)ds->ds_fsid_guid, 527 spa_name(dp->dp_spa), 528 dsobj); 529 } 530 } 531 } 532 ASSERT3P(ds->ds_dbuf, ==, dbuf); 533 ASSERT3P(dsl_dataset_phys(ds), ==, dbuf->db_data); 534 ASSERT(dsl_dataset_phys(ds)->ds_prev_snap_obj != 0 || 535 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 536 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 537 *dsp = ds; 538 return (0); 539 } 540 541 int 542 dsl_dataset_hold(dsl_pool_t *dp, const char *name, 543 void *tag, dsl_dataset_t **dsp) 544 { 545 dsl_dir_t *dd; 546 const char *snapname; 547 uint64_t obj; 548 int err = 0; 549 dsl_dataset_t *ds; 550 551 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname); 552 if (err != 0) 553 return (err); 554 555 ASSERT(dsl_pool_config_held(dp)); 556 obj = dsl_dir_phys(dd)->dd_head_dataset_obj; 557 if (obj != 0) 558 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 559 else 560 err = SET_ERROR(ENOENT); 561 562 /* we may be looking for a snapshot */ 563 if (err == 0 && snapname != NULL) { 564 dsl_dataset_t *snap_ds; 565 566 if (*snapname++ != '@') { 567 dsl_dataset_rele(ds, tag); 568 dsl_dir_rele(dd, FTAG); 569 return (SET_ERROR(ENOENT)); 570 } 571 572 dprintf("looking for snapshot '%s'\n", snapname); 573 err = dsl_dataset_snap_lookup(ds, snapname, &obj); 574 if (err == 0) 575 err = dsl_dataset_hold_obj(dp, obj, tag, &snap_ds); 576 dsl_dataset_rele(ds, tag); 577 578 if (err == 0) { 579 mutex_enter(&snap_ds->ds_lock); 580 if (snap_ds->ds_snapname[0] == 0) 581 (void) strlcpy(snap_ds->ds_snapname, snapname, 582 sizeof (snap_ds->ds_snapname)); 583 mutex_exit(&snap_ds->ds_lock); 584 ds = snap_ds; 585 } 586 } 587 if (err == 0) 588 *dsp = ds; 589 dsl_dir_rele(dd, FTAG); 590 return (err); 591 } 592 593 int 594 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, 595 void *tag, dsl_dataset_t **dsp) 596 { 597 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp); 598 if (err != 0) 599 return (err); 600 if (!dsl_dataset_tryown(*dsp, tag)) { 601 dsl_dataset_rele(*dsp, tag); 602 *dsp = NULL; 603 return (SET_ERROR(EBUSY)); 604 } 605 return (0); 606 } 607 608 int 609 dsl_dataset_own(dsl_pool_t *dp, const char *name, 610 void *tag, dsl_dataset_t **dsp) 611 { 612 int err = dsl_dataset_hold(dp, name, tag, dsp); 613 if (err != 0) 614 return (err); 615 if (!dsl_dataset_tryown(*dsp, tag)) { 616 dsl_dataset_rele(*dsp, tag); 617 return (SET_ERROR(EBUSY)); 618 } 619 return (0); 620 } 621 622 /* 623 * See the comment above dsl_pool_hold() for details. In summary, a long 624 * hold is used to prevent destruction of a dataset while the pool hold 625 * is dropped, allowing other concurrent operations (e.g. spa_sync()). 626 * 627 * The dataset and pool must be held when this function is called. After it 628 * is called, the pool hold may be released while the dataset is still held 629 * and accessed. 630 */ 631 void 632 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag) 633 { 634 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 635 (void) refcount_add(&ds->ds_longholds, tag); 636 } 637 638 void 639 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag) 640 { 641 (void) refcount_remove(&ds->ds_longholds, tag); 642 } 643 644 /* Return B_TRUE if there are any long holds on this dataset. */ 645 boolean_t 646 dsl_dataset_long_held(dsl_dataset_t *ds) 647 { 648 return (!refcount_is_zero(&ds->ds_longholds)); 649 } 650 651 void 652 dsl_dataset_name(dsl_dataset_t *ds, char *name) 653 { 654 if (ds == NULL) { 655 (void) strcpy(name, "mos"); 656 } else { 657 dsl_dir_name(ds->ds_dir, name); 658 VERIFY0(dsl_dataset_get_snapname(ds)); 659 if (ds->ds_snapname[0]) { 660 VERIFY3U(strlcat(name, "@", ZFS_MAX_DATASET_NAME_LEN), 661 <, ZFS_MAX_DATASET_NAME_LEN); 662 /* 663 * We use a "recursive" mutex so that we 664 * can call dprintf_ds() with ds_lock held. 665 */ 666 if (!MUTEX_HELD(&ds->ds_lock)) { 667 mutex_enter(&ds->ds_lock); 668 VERIFY3U(strlcat(name, ds->ds_snapname, 669 ZFS_MAX_DATASET_NAME_LEN), <, 670 ZFS_MAX_DATASET_NAME_LEN); 671 mutex_exit(&ds->ds_lock); 672 } else { 673 VERIFY3U(strlcat(name, ds->ds_snapname, 674 ZFS_MAX_DATASET_NAME_LEN), <, 675 ZFS_MAX_DATASET_NAME_LEN); 676 } 677 } 678 } 679 } 680 681 int 682 dsl_dataset_namelen(dsl_dataset_t *ds) 683 { 684 VERIFY0(dsl_dataset_get_snapname(ds)); 685 mutex_enter(&ds->ds_lock); 686 int len = dsl_dir_namelen(ds->ds_dir) + 1 + strlen(ds->ds_snapname); 687 mutex_exit(&ds->ds_lock); 688 return (len); 689 } 690 691 void 692 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 693 { 694 dmu_buf_rele(ds->ds_dbuf, tag); 695 } 696 697 void 698 dsl_dataset_disown(dsl_dataset_t *ds, void *tag) 699 { 700 ASSERT3P(ds->ds_owner, ==, tag); 701 ASSERT(ds->ds_dbuf != NULL); 702 703 mutex_enter(&ds->ds_lock); 704 ds->ds_owner = NULL; 705 mutex_exit(&ds->ds_lock); 706 dsl_dataset_long_rele(ds, tag); 707 dsl_dataset_rele(ds, tag); 708 } 709 710 boolean_t 711 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag) 712 { 713 boolean_t gotit = FALSE; 714 715 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 716 mutex_enter(&ds->ds_lock); 717 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) { 718 ds->ds_owner = tag; 719 dsl_dataset_long_hold(ds, tag); 720 gotit = TRUE; 721 } 722 mutex_exit(&ds->ds_lock); 723 return (gotit); 724 } 725 726 boolean_t 727 dsl_dataset_has_owner(dsl_dataset_t *ds) 728 { 729 boolean_t rv; 730 mutex_enter(&ds->ds_lock); 731 rv = (ds->ds_owner != NULL); 732 mutex_exit(&ds->ds_lock); 733 return (rv); 734 } 735 736 static void 737 dsl_dataset_activate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 738 { 739 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 740 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 741 uint64_t zero = 0; 742 743 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 744 745 spa_feature_incr(spa, f, tx); 746 dmu_object_zapify(mos, dsobj, DMU_OT_DSL_DATASET, tx); 747 748 VERIFY0(zap_add(mos, dsobj, spa_feature_table[f].fi_guid, 749 sizeof (zero), 1, &zero, tx)); 750 } 751 752 void 753 dsl_dataset_deactivate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx) 754 { 755 spa_t *spa = dmu_tx_pool(tx)->dp_spa; 756 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset; 757 758 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET); 759 760 VERIFY0(zap_remove(mos, dsobj, spa_feature_table[f].fi_guid, tx)); 761 spa_feature_decr(spa, f, tx); 762 } 763 764 uint64_t 765 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 766 uint64_t flags, dmu_tx_t *tx) 767 { 768 dsl_pool_t *dp = dd->dd_pool; 769 dmu_buf_t *dbuf; 770 dsl_dataset_phys_t *dsphys; 771 uint64_t dsobj; 772 objset_t *mos = dp->dp_meta_objset; 773 774 if (origin == NULL) 775 origin = dp->dp_origin_snap; 776 777 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 778 ASSERT(origin == NULL || dsl_dataset_phys(origin)->ds_num_children > 0); 779 ASSERT(dmu_tx_is_syncing(tx)); 780 ASSERT(dsl_dir_phys(dd)->dd_head_dataset_obj == 0); 781 782 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 783 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 784 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 785 dmu_buf_will_dirty(dbuf, tx); 786 dsphys = dbuf->db_data; 787 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 788 dsphys->ds_dir_obj = dd->dd_object; 789 dsphys->ds_flags = flags; 790 dsphys->ds_fsid_guid = unique_create(); 791 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 792 sizeof (dsphys->ds_guid)); 793 dsphys->ds_snapnames_zapobj = 794 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 795 DMU_OT_NONE, 0, tx); 796 dsphys->ds_creation_time = gethrestime_sec(); 797 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 798 799 if (origin == NULL) { 800 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx); 801 } else { 802 dsl_dataset_t *ohds; /* head of the origin snapshot */ 803 804 dsphys->ds_prev_snap_obj = origin->ds_object; 805 dsphys->ds_prev_snap_txg = 806 dsl_dataset_phys(origin)->ds_creation_txg; 807 dsphys->ds_referenced_bytes = 808 dsl_dataset_phys(origin)->ds_referenced_bytes; 809 dsphys->ds_compressed_bytes = 810 dsl_dataset_phys(origin)->ds_compressed_bytes; 811 dsphys->ds_uncompressed_bytes = 812 dsl_dataset_phys(origin)->ds_uncompressed_bytes; 813 rrw_enter(&origin->ds_bp_rwlock, RW_READER, FTAG); 814 dsphys->ds_bp = dsl_dataset_phys(origin)->ds_bp; 815 rrw_exit(&origin->ds_bp_rwlock, FTAG); 816 817 /* 818 * Inherit flags that describe the dataset's contents 819 * (INCONSISTENT) or properties (Case Insensitive). 820 */ 821 dsphys->ds_flags |= dsl_dataset_phys(origin)->ds_flags & 822 (DS_FLAG_INCONSISTENT | DS_FLAG_CI_DATASET); 823 824 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 825 if (origin->ds_feature_inuse[f]) 826 dsl_dataset_activate_feature(dsobj, f, tx); 827 } 828 829 dmu_buf_will_dirty(origin->ds_dbuf, tx); 830 dsl_dataset_phys(origin)->ds_num_children++; 831 832 VERIFY0(dsl_dataset_hold_obj(dp, 833 dsl_dir_phys(origin->ds_dir)->dd_head_dataset_obj, 834 FTAG, &ohds)); 835 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist, 836 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx); 837 dsl_dataset_rele(ohds, FTAG); 838 839 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 840 if (dsl_dataset_phys(origin)->ds_next_clones_obj == 0) { 841 dsl_dataset_phys(origin)->ds_next_clones_obj = 842 zap_create(mos, 843 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 844 } 845 VERIFY0(zap_add_int(mos, 846 dsl_dataset_phys(origin)->ds_next_clones_obj, 847 dsobj, tx)); 848 } 849 850 dmu_buf_will_dirty(dd->dd_dbuf, tx); 851 dsl_dir_phys(dd)->dd_origin_obj = origin->ds_object; 852 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 853 if (dsl_dir_phys(origin->ds_dir)->dd_clones == 0) { 854 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); 855 dsl_dir_phys(origin->ds_dir)->dd_clones = 856 zap_create(mos, 857 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); 858 } 859 VERIFY0(zap_add_int(mos, 860 dsl_dir_phys(origin->ds_dir)->dd_clones, 861 dsobj, tx)); 862 } 863 } 864 865 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 866 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 867 868 dmu_buf_rele(dbuf, FTAG); 869 870 dmu_buf_will_dirty(dd->dd_dbuf, tx); 871 dsl_dir_phys(dd)->dd_head_dataset_obj = dsobj; 872 873 return (dsobj); 874 } 875 876 static void 877 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx) 878 { 879 objset_t *os; 880 881 VERIFY0(dmu_objset_from_ds(ds, &os)); 882 if (bcmp(&os->os_zil_header, &zero_zil, sizeof (zero_zil)) != 0) { 883 dsl_pool_t *dp = ds->ds_dir->dd_pool; 884 zio_t *zio; 885 886 bzero(&os->os_zil_header, sizeof (os->os_zil_header)); 887 888 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 889 dsl_dataset_sync(ds, zio, tx); 890 VERIFY0(zio_wait(zio)); 891 892 /* dsl_dataset_sync_done will drop this reference. */ 893 dmu_buf_add_ref(ds->ds_dbuf, ds); 894 dsl_dataset_sync_done(ds, tx); 895 } 896 } 897 898 uint64_t 899 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 900 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 901 { 902 dsl_pool_t *dp = pdd->dd_pool; 903 uint64_t dsobj, ddobj; 904 dsl_dir_t *dd; 905 906 ASSERT(dmu_tx_is_syncing(tx)); 907 ASSERT(lastname[0] != '@'); 908 909 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 910 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd)); 911 912 dsobj = dsl_dataset_create_sync_dd(dd, origin, 913 flags & ~DS_CREATE_FLAG_NODIRTY, tx); 914 915 dsl_deleg_set_create_perms(dd, tx, cr); 916 917 /* 918 * Since we're creating a new node we know it's a leaf, so we can 919 * initialize the counts if the limit feature is active. 920 */ 921 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) { 922 uint64_t cnt = 0; 923 objset_t *os = dd->dd_pool->dp_meta_objset; 924 925 dsl_dir_zapify(dd, tx); 926 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT, 927 sizeof (cnt), 1, &cnt, tx)); 928 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT, 929 sizeof (cnt), 1, &cnt, tx)); 930 } 931 932 dsl_dir_rele(dd, FTAG); 933 934 /* 935 * If we are creating a clone, make sure we zero out any stale 936 * data from the origin snapshots zil header. 937 */ 938 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) { 939 dsl_dataset_t *ds; 940 941 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 942 dsl_dataset_zero_zil(ds, tx); 943 dsl_dataset_rele(ds, FTAG); 944 } 945 946 return (dsobj); 947 } 948 949 /* 950 * The unique space in the head dataset can be calculated by subtracting 951 * the space used in the most recent snapshot, that is still being used 952 * in this file system, from the space currently in use. To figure out 953 * the space in the most recent snapshot still in use, we need to take 954 * the total space used in the snapshot and subtract out the space that 955 * has been freed up since the snapshot was taken. 956 */ 957 void 958 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 959 { 960 uint64_t mrs_used; 961 uint64_t dlused, dlcomp, dluncomp; 962 963 ASSERT(!ds->ds_is_snapshot); 964 965 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) 966 mrs_used = dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes; 967 else 968 mrs_used = 0; 969 970 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp); 971 972 ASSERT3U(dlused, <=, mrs_used); 973 dsl_dataset_phys(ds)->ds_unique_bytes = 974 dsl_dataset_phys(ds)->ds_referenced_bytes - (mrs_used - dlused); 975 976 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 977 SPA_VERSION_UNIQUE_ACCURATE) 978 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 979 } 980 981 void 982 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, 983 dmu_tx_t *tx) 984 { 985 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 986 uint64_t count; 987 int err; 988 989 ASSERT(dsl_dataset_phys(ds)->ds_num_children >= 2); 990 err = zap_remove_int(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 991 obj, tx); 992 /* 993 * The err should not be ENOENT, but a bug in a previous version 994 * of the code could cause upgrade_clones_cb() to not set 995 * ds_next_snap_obj when it should, leading to a missing entry. 996 * If we knew that the pool was created after 997 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't 998 * ENOENT. However, at least we can check that we don't have 999 * too many entries in the next_clones_obj even after failing to 1000 * remove this one. 1001 */ 1002 if (err != ENOENT) 1003 VERIFY0(err); 1004 ASSERT0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1005 &count)); 1006 ASSERT3U(count, <=, dsl_dataset_phys(ds)->ds_num_children - 2); 1007 } 1008 1009 1010 blkptr_t * 1011 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1012 { 1013 return (&dsl_dataset_phys(ds)->ds_bp); 1014 } 1015 1016 spa_t * 1017 dsl_dataset_get_spa(dsl_dataset_t *ds) 1018 { 1019 return (ds->ds_dir->dd_pool->dp_spa); 1020 } 1021 1022 void 1023 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1024 { 1025 dsl_pool_t *dp; 1026 1027 if (ds == NULL) /* this is the meta-objset */ 1028 return; 1029 1030 ASSERT(ds->ds_objset != NULL); 1031 1032 if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) 1033 panic("dirtying snapshot!"); 1034 1035 /* Must not dirty a dataset in the same txg where it got snapshotted. */ 1036 ASSERT3U(tx->tx_txg, >, dsl_dataset_phys(ds)->ds_prev_snap_txg); 1037 1038 dp = ds->ds_dir->dd_pool; 1039 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) { 1040 /* up the hold count until we can be written out */ 1041 dmu_buf_add_ref(ds->ds_dbuf, ds); 1042 } 1043 } 1044 1045 boolean_t 1046 dsl_dataset_is_dirty(dsl_dataset_t *ds) 1047 { 1048 for (int t = 0; t < TXG_SIZE; t++) { 1049 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 1050 ds, t)) 1051 return (B_TRUE); 1052 } 1053 return (B_FALSE); 1054 } 1055 1056 static int 1057 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1058 { 1059 uint64_t asize; 1060 1061 if (!dmu_tx_is_syncing(tx)) 1062 return (0); 1063 1064 /* 1065 * If there's an fs-only reservation, any blocks that might become 1066 * owned by the snapshot dataset must be accommodated by space 1067 * outside of the reservation. 1068 */ 1069 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds)); 1070 asize = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, ds->ds_reserved); 1071 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 1072 return (SET_ERROR(ENOSPC)); 1073 1074 /* 1075 * Propagate any reserved space for this snapshot to other 1076 * snapshot checks in this sync group. 1077 */ 1078 if (asize > 0) 1079 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1080 1081 return (0); 1082 } 1083 1084 int 1085 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname, 1086 dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr) 1087 { 1088 int error; 1089 uint64_t value; 1090 1091 ds->ds_trysnap_txg = tx->tx_txg; 1092 1093 if (!dmu_tx_is_syncing(tx)) 1094 return (0); 1095 1096 /* 1097 * We don't allow multiple snapshots of the same txg. If there 1098 * is already one, try again. 1099 */ 1100 if (dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg) 1101 return (SET_ERROR(EAGAIN)); 1102 1103 /* 1104 * Check for conflicting snapshot name. 1105 */ 1106 error = dsl_dataset_snap_lookup(ds, snapname, &value); 1107 if (error == 0) 1108 return (SET_ERROR(EEXIST)); 1109 if (error != ENOENT) 1110 return (error); 1111 1112 /* 1113 * We don't allow taking snapshots of inconsistent datasets, such as 1114 * those into which we are currently receiving. However, if we are 1115 * creating this snapshot as part of a receive, this check will be 1116 * executed atomically with respect to the completion of the receive 1117 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this 1118 * case we ignore this, knowing it will be fixed up for us shortly in 1119 * dmu_recv_end_sync(). 1120 */ 1121 if (!recv && DS_IS_INCONSISTENT(ds)) 1122 return (SET_ERROR(EBUSY)); 1123 1124 /* 1125 * Skip the check for temporary snapshots or if we have already checked 1126 * the counts in dsl_dataset_snapshot_check. This means we really only 1127 * check the count here when we're receiving a stream. 1128 */ 1129 if (cnt != 0 && cr != NULL) { 1130 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1131 ZFS_PROP_SNAPSHOT_LIMIT, NULL, cr); 1132 if (error != 0) 1133 return (error); 1134 } 1135 1136 error = dsl_dataset_snapshot_reserve_space(ds, tx); 1137 if (error != 0) 1138 return (error); 1139 1140 return (0); 1141 } 1142 1143 int 1144 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx) 1145 { 1146 dsl_dataset_snapshot_arg_t *ddsa = arg; 1147 dsl_pool_t *dp = dmu_tx_pool(tx); 1148 nvpair_t *pair; 1149 int rv = 0; 1150 1151 /* 1152 * Pre-compute how many total new snapshots will be created for each 1153 * level in the tree and below. This is needed for validating the 1154 * snapshot limit when either taking a recursive snapshot or when 1155 * taking multiple snapshots. 1156 * 1157 * The problem is that the counts are not actually adjusted when 1158 * we are checking, only when we finally sync. For a single snapshot, 1159 * this is easy, the count will increase by 1 at each node up the tree, 1160 * but its more complicated for the recursive/multiple snapshot case. 1161 * 1162 * The dsl_fs_ss_limit_check function does recursively check the count 1163 * at each level up the tree but since it is validating each snapshot 1164 * independently we need to be sure that we are validating the complete 1165 * count for the entire set of snapshots. We do this by rolling up the 1166 * counts for each component of the name into an nvlist and then 1167 * checking each of those cases with the aggregated count. 1168 * 1169 * This approach properly handles not only the recursive snapshot 1170 * case (where we get all of those on the ddsa_snaps list) but also 1171 * the sibling case (e.g. snapshot a/b and a/c so that we will also 1172 * validate the limit on 'a' using a count of 2). 1173 * 1174 * We validate the snapshot names in the third loop and only report 1175 * name errors once. 1176 */ 1177 if (dmu_tx_is_syncing(tx)) { 1178 nvlist_t *cnt_track = NULL; 1179 cnt_track = fnvlist_alloc(); 1180 1181 /* Rollup aggregated counts into the cnt_track list */ 1182 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1183 pair != NULL; 1184 pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1185 char *pdelim; 1186 uint64_t val; 1187 char nm[MAXPATHLEN]; 1188 1189 (void) strlcpy(nm, nvpair_name(pair), sizeof (nm)); 1190 pdelim = strchr(nm, '@'); 1191 if (pdelim == NULL) 1192 continue; 1193 *pdelim = '\0'; 1194 1195 do { 1196 if (nvlist_lookup_uint64(cnt_track, nm, 1197 &val) == 0) { 1198 /* update existing entry */ 1199 fnvlist_add_uint64(cnt_track, nm, 1200 val + 1); 1201 } else { 1202 /* add to list */ 1203 fnvlist_add_uint64(cnt_track, nm, 1); 1204 } 1205 1206 pdelim = strrchr(nm, '/'); 1207 if (pdelim != NULL) 1208 *pdelim = '\0'; 1209 } while (pdelim != NULL); 1210 } 1211 1212 /* Check aggregated counts at each level */ 1213 for (pair = nvlist_next_nvpair(cnt_track, NULL); 1214 pair != NULL; pair = nvlist_next_nvpair(cnt_track, pair)) { 1215 int error = 0; 1216 char *name; 1217 uint64_t cnt = 0; 1218 dsl_dataset_t *ds; 1219 1220 name = nvpair_name(pair); 1221 cnt = fnvpair_value_uint64(pair); 1222 ASSERT(cnt > 0); 1223 1224 error = dsl_dataset_hold(dp, name, FTAG, &ds); 1225 if (error == 0) { 1226 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt, 1227 ZFS_PROP_SNAPSHOT_LIMIT, NULL, 1228 ddsa->ddsa_cr); 1229 dsl_dataset_rele(ds, FTAG); 1230 } 1231 1232 if (error != 0) { 1233 if (ddsa->ddsa_errors != NULL) 1234 fnvlist_add_int32(ddsa->ddsa_errors, 1235 name, error); 1236 rv = error; 1237 /* only report one error for this check */ 1238 break; 1239 } 1240 } 1241 nvlist_free(cnt_track); 1242 } 1243 1244 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1245 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1246 int error = 0; 1247 dsl_dataset_t *ds; 1248 char *name, *atp; 1249 char dsname[ZFS_MAX_DATASET_NAME_LEN]; 1250 1251 name = nvpair_name(pair); 1252 if (strlen(name) >= ZFS_MAX_DATASET_NAME_LEN) 1253 error = SET_ERROR(ENAMETOOLONG); 1254 if (error == 0) { 1255 atp = strchr(name, '@'); 1256 if (atp == NULL) 1257 error = SET_ERROR(EINVAL); 1258 if (error == 0) 1259 (void) strlcpy(dsname, name, atp - name + 1); 1260 } 1261 if (error == 0) 1262 error = dsl_dataset_hold(dp, dsname, FTAG, &ds); 1263 if (error == 0) { 1264 /* passing 0/NULL skips dsl_fs_ss_limit_check */ 1265 error = dsl_dataset_snapshot_check_impl(ds, 1266 atp + 1, tx, B_FALSE, 0, NULL); 1267 dsl_dataset_rele(ds, FTAG); 1268 } 1269 1270 if (error != 0) { 1271 if (ddsa->ddsa_errors != NULL) { 1272 fnvlist_add_int32(ddsa->ddsa_errors, 1273 name, error); 1274 } 1275 rv = error; 1276 } 1277 } 1278 1279 return (rv); 1280 } 1281 1282 void 1283 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname, 1284 dmu_tx_t *tx) 1285 { 1286 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1287 dmu_buf_t *dbuf; 1288 dsl_dataset_phys_t *dsphys; 1289 uint64_t dsobj, crtxg; 1290 objset_t *mos = dp->dp_meta_objset; 1291 objset_t *os; 1292 1293 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); 1294 1295 /* 1296 * If we are on an old pool, the zil must not be active, in which 1297 * case it will be zeroed. Usually zil_suspend() accomplishes this. 1298 */ 1299 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP || 1300 dmu_objset_from_ds(ds, &os) != 0 || 1301 bcmp(&os->os_phys->os_zil_header, &zero_zil, 1302 sizeof (zero_zil)) == 0); 1303 1304 /* Should not snapshot a dirty dataset. */ 1305 ASSERT(!txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets, 1306 ds, tx->tx_txg)); 1307 1308 dsl_fs_ss_count_adjust(ds->ds_dir, 1, DD_FIELD_SNAPSHOT_COUNT, tx); 1309 1310 /* 1311 * The origin's ds_creation_txg has to be < TXG_INITIAL 1312 */ 1313 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1314 crtxg = 1; 1315 else 1316 crtxg = tx->tx_txg; 1317 1318 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1319 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1320 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1321 dmu_buf_will_dirty(dbuf, tx); 1322 dsphys = dbuf->db_data; 1323 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1324 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1325 dsphys->ds_fsid_guid = unique_create(); 1326 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1327 sizeof (dsphys->ds_guid)); 1328 dsphys->ds_prev_snap_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 1329 dsphys->ds_prev_snap_txg = dsl_dataset_phys(ds)->ds_prev_snap_txg; 1330 dsphys->ds_next_snap_obj = ds->ds_object; 1331 dsphys->ds_num_children = 1; 1332 dsphys->ds_creation_time = gethrestime_sec(); 1333 dsphys->ds_creation_txg = crtxg; 1334 dsphys->ds_deadlist_obj = dsl_dataset_phys(ds)->ds_deadlist_obj; 1335 dsphys->ds_referenced_bytes = dsl_dataset_phys(ds)->ds_referenced_bytes; 1336 dsphys->ds_compressed_bytes = dsl_dataset_phys(ds)->ds_compressed_bytes; 1337 dsphys->ds_uncompressed_bytes = 1338 dsl_dataset_phys(ds)->ds_uncompressed_bytes; 1339 dsphys->ds_flags = dsl_dataset_phys(ds)->ds_flags; 1340 rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); 1341 dsphys->ds_bp = dsl_dataset_phys(ds)->ds_bp; 1342 rrw_exit(&ds->ds_bp_rwlock, FTAG); 1343 dmu_buf_rele(dbuf, FTAG); 1344 1345 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1346 if (ds->ds_feature_inuse[f]) 1347 dsl_dataset_activate_feature(dsobj, f, tx); 1348 } 1349 1350 ASSERT3U(ds->ds_prev != 0, ==, 1351 dsl_dataset_phys(ds)->ds_prev_snap_obj != 0); 1352 if (ds->ds_prev) { 1353 uint64_t next_clones_obj = 1354 dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj; 1355 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1356 ds->ds_object || 1357 dsl_dataset_phys(ds->ds_prev)->ds_num_children > 1); 1358 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == 1359 ds->ds_object) { 1360 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1361 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==, 1362 dsl_dataset_phys(ds->ds_prev)->ds_creation_txg); 1363 dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj = dsobj; 1364 } else if (next_clones_obj != 0) { 1365 dsl_dataset_remove_from_next_clones(ds->ds_prev, 1366 dsphys->ds_next_snap_obj, tx); 1367 VERIFY0(zap_add_int(mos, 1368 next_clones_obj, dsobj, tx)); 1369 } 1370 } 1371 1372 /* 1373 * If we have a reference-reservation on this dataset, we will 1374 * need to increase the amount of refreservation being charged 1375 * since our unique space is going to zero. 1376 */ 1377 if (ds->ds_reserved) { 1378 int64_t delta; 1379 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 1380 delta = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, 1381 ds->ds_reserved); 1382 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1383 delta, 0, 0, tx); 1384 } 1385 1386 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1387 dsl_dataset_phys(ds)->ds_deadlist_obj = 1388 dsl_deadlist_clone(&ds->ds_deadlist, UINT64_MAX, 1389 dsl_dataset_phys(ds)->ds_prev_snap_obj, tx); 1390 dsl_deadlist_close(&ds->ds_deadlist); 1391 dsl_deadlist_open(&ds->ds_deadlist, mos, 1392 dsl_dataset_phys(ds)->ds_deadlist_obj); 1393 dsl_deadlist_add_key(&ds->ds_deadlist, 1394 dsl_dataset_phys(ds)->ds_prev_snap_txg, tx); 1395 1396 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, <, tx->tx_txg); 1397 dsl_dataset_phys(ds)->ds_prev_snap_obj = dsobj; 1398 dsl_dataset_phys(ds)->ds_prev_snap_txg = crtxg; 1399 dsl_dataset_phys(ds)->ds_unique_bytes = 0; 1400 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1401 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1402 1403 VERIFY0(zap_add(mos, dsl_dataset_phys(ds)->ds_snapnames_zapobj, 1404 snapname, 8, 1, &dsobj, tx)); 1405 1406 if (ds->ds_prev) 1407 dsl_dataset_rele(ds->ds_prev, ds); 1408 VERIFY0(dsl_dataset_hold_obj(dp, 1409 dsl_dataset_phys(ds)->ds_prev_snap_obj, ds, &ds->ds_prev)); 1410 1411 dsl_scan_ds_snapshotted(ds, tx); 1412 1413 dsl_dir_snap_cmtime_update(ds->ds_dir); 1414 1415 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, ""); 1416 } 1417 1418 void 1419 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx) 1420 { 1421 dsl_dataset_snapshot_arg_t *ddsa = arg; 1422 dsl_pool_t *dp = dmu_tx_pool(tx); 1423 nvpair_t *pair; 1424 1425 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL); 1426 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) { 1427 dsl_dataset_t *ds; 1428 char *name, *atp; 1429 char dsname[ZFS_MAX_DATASET_NAME_LEN]; 1430 1431 name = nvpair_name(pair); 1432 atp = strchr(name, '@'); 1433 (void) strlcpy(dsname, name, atp - name + 1); 1434 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds)); 1435 1436 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx); 1437 if (ddsa->ddsa_props != NULL) { 1438 dsl_props_set_sync_impl(ds->ds_prev, 1439 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx); 1440 } 1441 dsl_dataset_rele(ds, FTAG); 1442 } 1443 } 1444 1445 /* 1446 * The snapshots must all be in the same pool. 1447 * All-or-nothing: if there are any failures, nothing will be modified. 1448 */ 1449 int 1450 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors) 1451 { 1452 dsl_dataset_snapshot_arg_t ddsa; 1453 nvpair_t *pair; 1454 boolean_t needsuspend; 1455 int error; 1456 spa_t *spa; 1457 char *firstname; 1458 nvlist_t *suspended = NULL; 1459 1460 pair = nvlist_next_nvpair(snaps, NULL); 1461 if (pair == NULL) 1462 return (0); 1463 firstname = nvpair_name(pair); 1464 1465 error = spa_open(firstname, &spa, FTAG); 1466 if (error != 0) 1467 return (error); 1468 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1469 spa_close(spa, FTAG); 1470 1471 if (needsuspend) { 1472 suspended = fnvlist_alloc(); 1473 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; 1474 pair = nvlist_next_nvpair(snaps, pair)) { 1475 char fsname[ZFS_MAX_DATASET_NAME_LEN]; 1476 char *snapname = nvpair_name(pair); 1477 char *atp; 1478 void *cookie; 1479 1480 atp = strchr(snapname, '@'); 1481 if (atp == NULL) { 1482 error = SET_ERROR(EINVAL); 1483 break; 1484 } 1485 (void) strlcpy(fsname, snapname, atp - snapname + 1); 1486 1487 error = zil_suspend(fsname, &cookie); 1488 if (error != 0) 1489 break; 1490 fnvlist_add_uint64(suspended, fsname, 1491 (uintptr_t)cookie); 1492 } 1493 } 1494 1495 ddsa.ddsa_snaps = snaps; 1496 ddsa.ddsa_props = props; 1497 ddsa.ddsa_errors = errors; 1498 ddsa.ddsa_cr = CRED(); 1499 1500 if (error == 0) { 1501 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check, 1502 dsl_dataset_snapshot_sync, &ddsa, 1503 fnvlist_num_pairs(snaps) * 3, ZFS_SPACE_CHECK_NORMAL); 1504 } 1505 1506 if (suspended != NULL) { 1507 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL; 1508 pair = nvlist_next_nvpair(suspended, pair)) { 1509 zil_resume((void *)(uintptr_t) 1510 fnvpair_value_uint64(pair)); 1511 } 1512 fnvlist_free(suspended); 1513 } 1514 1515 return (error); 1516 } 1517 1518 typedef struct dsl_dataset_snapshot_tmp_arg { 1519 const char *ddsta_fsname; 1520 const char *ddsta_snapname; 1521 minor_t ddsta_cleanup_minor; 1522 const char *ddsta_htag; 1523 } dsl_dataset_snapshot_tmp_arg_t; 1524 1525 static int 1526 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx) 1527 { 1528 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1529 dsl_pool_t *dp = dmu_tx_pool(tx); 1530 dsl_dataset_t *ds; 1531 int error; 1532 1533 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds); 1534 if (error != 0) 1535 return (error); 1536 1537 /* NULL cred means no limit check for tmp snapshot */ 1538 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, 1539 tx, B_FALSE, 0, NULL); 1540 if (error != 0) { 1541 dsl_dataset_rele(ds, FTAG); 1542 return (error); 1543 } 1544 1545 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) { 1546 dsl_dataset_rele(ds, FTAG); 1547 return (SET_ERROR(ENOTSUP)); 1548 } 1549 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag, 1550 B_TRUE, tx); 1551 if (error != 0) { 1552 dsl_dataset_rele(ds, FTAG); 1553 return (error); 1554 } 1555 1556 dsl_dataset_rele(ds, FTAG); 1557 return (0); 1558 } 1559 1560 static void 1561 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx) 1562 { 1563 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg; 1564 dsl_pool_t *dp = dmu_tx_pool(tx); 1565 dsl_dataset_t *ds; 1566 1567 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds)); 1568 1569 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx); 1570 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag, 1571 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx); 1572 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx); 1573 1574 dsl_dataset_rele(ds, FTAG); 1575 } 1576 1577 int 1578 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname, 1579 minor_t cleanup_minor, const char *htag) 1580 { 1581 dsl_dataset_snapshot_tmp_arg_t ddsta; 1582 int error; 1583 spa_t *spa; 1584 boolean_t needsuspend; 1585 void *cookie; 1586 1587 ddsta.ddsta_fsname = fsname; 1588 ddsta.ddsta_snapname = snapname; 1589 ddsta.ddsta_cleanup_minor = cleanup_minor; 1590 ddsta.ddsta_htag = htag; 1591 1592 error = spa_open(fsname, &spa, FTAG); 1593 if (error != 0) 1594 return (error); 1595 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP); 1596 spa_close(spa, FTAG); 1597 1598 if (needsuspend) { 1599 error = zil_suspend(fsname, &cookie); 1600 if (error != 0) 1601 return (error); 1602 } 1603 1604 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check, 1605 dsl_dataset_snapshot_tmp_sync, &ddsta, 3, ZFS_SPACE_CHECK_RESERVED); 1606 1607 if (needsuspend) 1608 zil_resume(cookie); 1609 return (error); 1610 } 1611 1612 void 1613 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1614 { 1615 ASSERT(dmu_tx_is_syncing(tx)); 1616 ASSERT(ds->ds_objset != NULL); 1617 ASSERT(dsl_dataset_phys(ds)->ds_next_snap_obj == 0); 1618 1619 /* 1620 * in case we had to change ds_fsid_guid when we opened it, 1621 * sync it out now. 1622 */ 1623 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1624 dsl_dataset_phys(ds)->ds_fsid_guid = ds->ds_fsid_guid; 1625 1626 if (ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] != 0) { 1627 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1628 ds->ds_object, DS_FIELD_RESUME_OBJECT, 8, 1, 1629 &ds->ds_resume_object[tx->tx_txg & TXG_MASK], tx)); 1630 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1631 ds->ds_object, DS_FIELD_RESUME_OFFSET, 8, 1, 1632 &ds->ds_resume_offset[tx->tx_txg & TXG_MASK], tx)); 1633 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, 1634 ds->ds_object, DS_FIELD_RESUME_BYTES, 8, 1, 1635 &ds->ds_resume_bytes[tx->tx_txg & TXG_MASK], tx)); 1636 ds->ds_resume_object[tx->tx_txg & TXG_MASK] = 0; 1637 ds->ds_resume_offset[tx->tx_txg & TXG_MASK] = 0; 1638 ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] = 0; 1639 } 1640 1641 dmu_objset_sync(ds->ds_objset, zio, tx); 1642 1643 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 1644 if (ds->ds_feature_activation_needed[f]) { 1645 if (ds->ds_feature_inuse[f]) 1646 continue; 1647 dsl_dataset_activate_feature(ds->ds_object, f, tx); 1648 ds->ds_feature_inuse[f] = B_TRUE; 1649 } 1650 } 1651 } 1652 1653 static int 1654 deadlist_enqueue_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx) 1655 { 1656 dsl_deadlist_t *dl = arg; 1657 dsl_deadlist_insert(dl, bp, tx); 1658 return (0); 1659 } 1660 1661 void 1662 dsl_dataset_sync_done(dsl_dataset_t *ds, dmu_tx_t *tx) 1663 { 1664 objset_t *os = ds->ds_objset; 1665 1666 bplist_iterate(&ds->ds_pending_deadlist, 1667 deadlist_enqueue_cb, &ds->ds_deadlist, tx); 1668 1669 if (os->os_synced_dnodes != NULL) { 1670 multilist_destroy(os->os_synced_dnodes); 1671 os->os_synced_dnodes = NULL; 1672 } 1673 1674 ASSERT(!dmu_objset_is_dirty(os, dmu_tx_get_txg(tx))); 1675 1676 dmu_buf_rele(ds->ds_dbuf, ds); 1677 } 1678 1679 int 1680 get_clones_stat_impl(dsl_dataset_t *ds, nvlist_t *val) 1681 { 1682 uint64_t count = 0; 1683 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1684 zap_cursor_t zc; 1685 zap_attribute_t za; 1686 1687 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool)); 1688 1689 /* 1690 * There may be missing entries in ds_next_clones_obj 1691 * due to a bug in a previous version of the code. 1692 * Only trust it if it has the right number of entries. 1693 */ 1694 if (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) { 1695 VERIFY0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, 1696 &count)); 1697 } 1698 if (count != dsl_dataset_phys(ds)->ds_num_children - 1) { 1699 return (ENOENT); 1700 } 1701 for (zap_cursor_init(&zc, mos, 1702 dsl_dataset_phys(ds)->ds_next_clones_obj); 1703 zap_cursor_retrieve(&zc, &za) == 0; 1704 zap_cursor_advance(&zc)) { 1705 dsl_dataset_t *clone; 1706 char buf[ZFS_MAX_DATASET_NAME_LEN]; 1707 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, 1708 za.za_first_integer, FTAG, &clone)); 1709 dsl_dir_name(clone->ds_dir, buf); 1710 fnvlist_add_boolean(val, buf); 1711 dsl_dataset_rele(clone, FTAG); 1712 } 1713 zap_cursor_fini(&zc); 1714 return (0); 1715 } 1716 1717 void 1718 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv) 1719 { 1720 nvlist_t *propval = fnvlist_alloc(); 1721 nvlist_t *val; 1722 1723 /* 1724 * We use nvlist_alloc() instead of fnvlist_alloc() because the 1725 * latter would allocate the list with NV_UNIQUE_NAME flag. 1726 * As a result, every time a clone name is appended to the list 1727 * it would be (linearly) searched for for a duplicate name. 1728 * We already know that all clone names must be unique and we 1729 * want avoid the quadratic complexity of double-checking that 1730 * because we can have a large number of clones. 1731 */ 1732 VERIFY0(nvlist_alloc(&val, 0, KM_SLEEP)); 1733 1734 if (get_clones_stat_impl(ds, val) == 0) { 1735 fnvlist_add_nvlist(propval, ZPROP_VALUE, val); 1736 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), 1737 propval); 1738 } 1739 1740 nvlist_free(val); 1741 nvlist_free(propval); 1742 } 1743 1744 /* 1745 * Returns a string that represents the receive resume stats token. It should 1746 * be freed with strfree(). 1747 */ 1748 char * 1749 get_receive_resume_stats_impl(dsl_dataset_t *ds) 1750 { 1751 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1752 1753 if (dsl_dataset_has_resume_receive_state(ds)) { 1754 char *str; 1755 void *packed; 1756 uint8_t *compressed; 1757 uint64_t val; 1758 nvlist_t *token_nv = fnvlist_alloc(); 1759 size_t packed_size, compressed_size; 1760 1761 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1762 DS_FIELD_RESUME_FROMGUID, sizeof (val), 1, &val) == 0) { 1763 fnvlist_add_uint64(token_nv, "fromguid", val); 1764 } 1765 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1766 DS_FIELD_RESUME_OBJECT, sizeof (val), 1, &val) == 0) { 1767 fnvlist_add_uint64(token_nv, "object", val); 1768 } 1769 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1770 DS_FIELD_RESUME_OFFSET, sizeof (val), 1, &val) == 0) { 1771 fnvlist_add_uint64(token_nv, "offset", val); 1772 } 1773 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1774 DS_FIELD_RESUME_BYTES, sizeof (val), 1, &val) == 0) { 1775 fnvlist_add_uint64(token_nv, "bytes", val); 1776 } 1777 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1778 DS_FIELD_RESUME_TOGUID, sizeof (val), 1, &val) == 0) { 1779 fnvlist_add_uint64(token_nv, "toguid", val); 1780 } 1781 char buf[256]; 1782 if (zap_lookup(dp->dp_meta_objset, ds->ds_object, 1783 DS_FIELD_RESUME_TONAME, 1, sizeof (buf), buf) == 0) { 1784 fnvlist_add_string(token_nv, "toname", buf); 1785 } 1786 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1787 DS_FIELD_RESUME_LARGEBLOCK) == 0) { 1788 fnvlist_add_boolean(token_nv, "largeblockok"); 1789 } 1790 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1791 DS_FIELD_RESUME_EMBEDOK) == 0) { 1792 fnvlist_add_boolean(token_nv, "embedok"); 1793 } 1794 if (zap_contains(dp->dp_meta_objset, ds->ds_object, 1795 DS_FIELD_RESUME_COMPRESSOK) == 0) { 1796 fnvlist_add_boolean(token_nv, "compressok"); 1797 } 1798 packed = fnvlist_pack(token_nv, &packed_size); 1799 fnvlist_free(token_nv); 1800 compressed = kmem_alloc(packed_size, KM_SLEEP); 1801 1802 compressed_size = gzip_compress(packed, compressed, 1803 packed_size, packed_size, 6); 1804 1805 zio_cksum_t cksum; 1806 fletcher_4_native(compressed, compressed_size, NULL, &cksum); 1807 1808 str = kmem_alloc(compressed_size * 2 + 1, KM_SLEEP); 1809 for (int i = 0; i < compressed_size; i++) { 1810 (void) sprintf(str + i * 2, "%02x", compressed[i]); 1811 } 1812 str[compressed_size * 2] = '\0'; 1813 char *propval = kmem_asprintf("%u-%llx-%llx-%s", 1814 ZFS_SEND_RESUME_TOKEN_VERSION, 1815 (longlong_t)cksum.zc_word[0], 1816 (longlong_t)packed_size, str); 1817 kmem_free(packed, packed_size); 1818 kmem_free(str, compressed_size * 2 + 1); 1819 kmem_free(compressed, packed_size); 1820 return (propval); 1821 } 1822 return (strdup("")); 1823 } 1824 1825 /* 1826 * Returns a string that represents the receive resume stats token of the 1827 * dataset's child. It should be freed with strfree(). 1828 */ 1829 char * 1830 get_child_receive_stats(dsl_dataset_t *ds) 1831 { 1832 char recvname[ZFS_MAX_DATASET_NAME_LEN + 6]; 1833 dsl_dataset_t *recv_ds; 1834 dsl_dataset_name(ds, recvname); 1835 if (strlcat(recvname, "/", sizeof (recvname)) < 1836 sizeof (recvname) && 1837 strlcat(recvname, recv_clone_name, sizeof (recvname)) < 1838 sizeof (recvname) && 1839 dsl_dataset_hold(ds->ds_dir->dd_pool, recvname, FTAG, 1840 &recv_ds) == 0) { 1841 char *propval = get_receive_resume_stats_impl(recv_ds); 1842 dsl_dataset_rele(recv_ds, FTAG); 1843 return (propval); 1844 } 1845 return (strdup("")); 1846 } 1847 1848 static void 1849 get_receive_resume_stats(dsl_dataset_t *ds, nvlist_t *nv) 1850 { 1851 char *propval = get_receive_resume_stats_impl(ds); 1852 if (strcmp(propval, "") != 0) { 1853 dsl_prop_nvlist_add_string(nv, 1854 ZFS_PROP_RECEIVE_RESUME_TOKEN, propval); 1855 } else { 1856 char *childval = get_child_receive_stats(ds); 1857 if (strcmp(childval, "") != 0) { 1858 dsl_prop_nvlist_add_string(nv, 1859 ZFS_PROP_RECEIVE_RESUME_TOKEN, childval); 1860 } 1861 strfree(childval); 1862 } 1863 strfree(propval); 1864 } 1865 1866 uint64_t 1867 dsl_get_refratio(dsl_dataset_t *ds) 1868 { 1869 uint64_t ratio = dsl_dataset_phys(ds)->ds_compressed_bytes == 0 ? 100 : 1870 (dsl_dataset_phys(ds)->ds_uncompressed_bytes * 100 / 1871 dsl_dataset_phys(ds)->ds_compressed_bytes); 1872 return (ratio); 1873 } 1874 1875 uint64_t 1876 dsl_get_logicalreferenced(dsl_dataset_t *ds) 1877 { 1878 return (dsl_dataset_phys(ds)->ds_uncompressed_bytes); 1879 } 1880 1881 uint64_t 1882 dsl_get_compressratio(dsl_dataset_t *ds) 1883 { 1884 if (ds->ds_is_snapshot) { 1885 return (dsl_get_refratio(ds)); 1886 } else { 1887 dsl_dir_t *dd = ds->ds_dir; 1888 mutex_enter(&dd->dd_lock); 1889 uint64_t val = dsl_dir_get_compressratio(dd); 1890 mutex_exit(&dd->dd_lock); 1891 return (val); 1892 } 1893 } 1894 1895 uint64_t 1896 dsl_get_used(dsl_dataset_t *ds) 1897 { 1898 if (ds->ds_is_snapshot) { 1899 return (dsl_dataset_phys(ds)->ds_unique_bytes); 1900 } else { 1901 dsl_dir_t *dd = ds->ds_dir; 1902 mutex_enter(&dd->dd_lock); 1903 uint64_t val = dsl_dir_get_used(dd); 1904 mutex_exit(&dd->dd_lock); 1905 return (val); 1906 } 1907 } 1908 1909 uint64_t 1910 dsl_get_creation(dsl_dataset_t *ds) 1911 { 1912 return (dsl_dataset_phys(ds)->ds_creation_time); 1913 } 1914 1915 uint64_t 1916 dsl_get_creationtxg(dsl_dataset_t *ds) 1917 { 1918 return (dsl_dataset_phys(ds)->ds_creation_txg); 1919 } 1920 1921 uint64_t 1922 dsl_get_refquota(dsl_dataset_t *ds) 1923 { 1924 return (ds->ds_quota); 1925 } 1926 1927 uint64_t 1928 dsl_get_refreservation(dsl_dataset_t *ds) 1929 { 1930 return (ds->ds_reserved); 1931 } 1932 1933 uint64_t 1934 dsl_get_guid(dsl_dataset_t *ds) 1935 { 1936 return (dsl_dataset_phys(ds)->ds_guid); 1937 } 1938 1939 uint64_t 1940 dsl_get_unique(dsl_dataset_t *ds) 1941 { 1942 return (dsl_dataset_phys(ds)->ds_unique_bytes); 1943 } 1944 1945 uint64_t 1946 dsl_get_objsetid(dsl_dataset_t *ds) 1947 { 1948 return (ds->ds_object); 1949 } 1950 1951 uint64_t 1952 dsl_get_userrefs(dsl_dataset_t *ds) 1953 { 1954 return (ds->ds_userrefs); 1955 } 1956 1957 uint64_t 1958 dsl_get_defer_destroy(dsl_dataset_t *ds) 1959 { 1960 return (DS_IS_DEFER_DESTROY(ds) ? 1 : 0); 1961 } 1962 1963 uint64_t 1964 dsl_get_referenced(dsl_dataset_t *ds) 1965 { 1966 return (dsl_dataset_phys(ds)->ds_referenced_bytes); 1967 } 1968 1969 uint64_t 1970 dsl_get_numclones(dsl_dataset_t *ds) 1971 { 1972 ASSERT(ds->ds_is_snapshot); 1973 return (dsl_dataset_phys(ds)->ds_num_children - 1); 1974 } 1975 1976 uint64_t 1977 dsl_get_inconsistent(dsl_dataset_t *ds) 1978 { 1979 return ((dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT) ? 1980 1 : 0); 1981 } 1982 1983 uint64_t 1984 dsl_get_available(dsl_dataset_t *ds) 1985 { 1986 uint64_t refdbytes = dsl_get_referenced(ds); 1987 uint64_t availbytes = dsl_dir_space_available(ds->ds_dir, 1988 NULL, 0, TRUE); 1989 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) { 1990 availbytes += 1991 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes; 1992 } 1993 if (ds->ds_quota != 0) { 1994 /* 1995 * Adjust available bytes according to refquota 1996 */ 1997 if (refdbytes < ds->ds_quota) { 1998 availbytes = MIN(availbytes, 1999 ds->ds_quota - refdbytes); 2000 } else { 2001 availbytes = 0; 2002 } 2003 } 2004 return (availbytes); 2005 } 2006 2007 int 2008 dsl_get_written(dsl_dataset_t *ds, uint64_t *written) 2009 { 2010 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2011 dsl_dataset_t *prev; 2012 int err = dsl_dataset_hold_obj(dp, 2013 dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &prev); 2014 if (err == 0) { 2015 uint64_t comp, uncomp; 2016 err = dsl_dataset_space_written(prev, ds, written, 2017 &comp, &uncomp); 2018 dsl_dataset_rele(prev, FTAG); 2019 } 2020 return (err); 2021 } 2022 2023 /* 2024 * 'snap' should be a buffer of size ZFS_MAX_DATASET_NAME_LEN. 2025 */ 2026 int 2027 dsl_get_prev_snap(dsl_dataset_t *ds, char *snap) 2028 { 2029 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2030 if (ds->ds_prev != NULL && ds->ds_prev != dp->dp_origin_snap) { 2031 dsl_dataset_name(ds->ds_prev, snap); 2032 return (0); 2033 } else { 2034 return (ENOENT); 2035 } 2036 } 2037 2038 /* 2039 * Returns the mountpoint property and source for the given dataset in the value 2040 * and source buffers. The value buffer must be at least as large as MAXPATHLEN 2041 * and the source buffer as least as large a ZFS_MAX_DATASET_NAME_LEN. 2042 * Returns 0 on success and an error on failure. 2043 */ 2044 int 2045 dsl_get_mountpoint(dsl_dataset_t *ds, const char *dsname, char *value, 2046 char *source) 2047 { 2048 int error; 2049 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2050 2051 /* Retrieve the mountpoint value stored in the zap opbject */ 2052 error = dsl_prop_get_ds(ds, zfs_prop_to_name(ZFS_PROP_MOUNTPOINT), 1, 2053 ZAP_MAXVALUELEN, value, source); 2054 if (error != 0) { 2055 return (error); 2056 } 2057 2058 /* Process the dsname and source to find the full mountpoint string */ 2059 if (value[0] == '/') { 2060 char *buf = kmem_alloc(ZAP_MAXVALUELEN, KM_SLEEP); 2061 char *root = buf; 2062 const char *relpath; 2063 2064 /* 2065 * If we inherit the mountpoint, even from a dataset 2066 * with a received value, the source will be the path of 2067 * the dataset we inherit from. If source is 2068 * ZPROP_SOURCE_VAL_RECVD, the received value is not 2069 * inherited. 2070 */ 2071 if (strcmp(source, ZPROP_SOURCE_VAL_RECVD) == 0) { 2072 relpath = ""; 2073 } else { 2074 ASSERT0(strncmp(dsname, source, strlen(source))); 2075 relpath = dsname + strlen(source); 2076 if (relpath[0] == '/') 2077 relpath++; 2078 } 2079 2080 spa_altroot(dp->dp_spa, root, ZAP_MAXVALUELEN); 2081 2082 /* 2083 * Special case an alternate root of '/'. This will 2084 * avoid having multiple leading slashes in the 2085 * mountpoint path. 2086 */ 2087 if (strcmp(root, "/") == 0) 2088 root++; 2089 2090 /* 2091 * If the mountpoint is '/' then skip over this 2092 * if we are obtaining either an alternate root or 2093 * an inherited mountpoint. 2094 */ 2095 char *mnt = value; 2096 if (value[1] == '\0' && (root[0] != '\0' || 2097 relpath[0] != '\0')) 2098 mnt = value + 1; 2099 2100 if (relpath[0] == '\0') { 2101 (void) snprintf(value, ZAP_MAXVALUELEN, "%s%s", 2102 root, mnt); 2103 } else { 2104 (void) snprintf(value, ZAP_MAXVALUELEN, "%s%s%s%s", 2105 root, mnt, relpath[0] == '@' ? "" : "/", 2106 relpath); 2107 } 2108 kmem_free(buf, ZAP_MAXVALUELEN); 2109 } else { 2110 /* 'legacy' or 'none' */ 2111 (void) snprintf(value, ZAP_MAXVALUELEN, "%s", value); 2112 } 2113 return (0); 2114 } 2115 2116 void 2117 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 2118 { 2119 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2120 2121 ASSERT(dsl_pool_config_held(dp)); 2122 2123 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, 2124 dsl_get_refratio(ds)); 2125 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED, 2126 dsl_get_logicalreferenced(ds)); 2127 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, 2128 dsl_get_compressratio(ds)); 2129 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 2130 dsl_get_used(ds)); 2131 2132 if (ds->ds_is_snapshot) { 2133 get_clones_stat(ds, nv); 2134 } else { 2135 char buf[ZFS_MAX_DATASET_NAME_LEN]; 2136 if (dsl_get_prev_snap(ds, buf) == 0) 2137 dsl_prop_nvlist_add_string(nv, ZFS_PROP_PREV_SNAP, 2138 buf); 2139 dsl_dir_stats(ds->ds_dir, nv); 2140 } 2141 2142 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, 2143 dsl_get_available(ds)); 2144 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, 2145 dsl_get_referenced(ds)); 2146 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 2147 dsl_get_creation(ds)); 2148 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 2149 dsl_get_creationtxg(ds)); 2150 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 2151 dsl_get_refquota(ds)); 2152 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 2153 dsl_get_refreservation(ds)); 2154 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 2155 dsl_get_guid(ds)); 2156 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE, 2157 dsl_get_unique(ds)); 2158 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID, 2159 dsl_get_objsetid(ds)); 2160 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS, 2161 dsl_get_userrefs(ds)); 2162 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY, 2163 dsl_get_defer_destroy(ds)); 2164 2165 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { 2166 uint64_t written; 2167 if (dsl_get_written(ds, &written) == 0) { 2168 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN, 2169 written); 2170 } 2171 } 2172 2173 if (!dsl_dataset_is_snapshot(ds)) { 2174 /* 2175 * A failed "newfs" (e.g. full) resumable receive leaves 2176 * the stats set on this dataset. Check here for the prop. 2177 */ 2178 get_receive_resume_stats(ds, nv); 2179 2180 /* 2181 * A failed incremental resumable receive leaves the 2182 * stats set on our child named "%recv". Check the child 2183 * for the prop. 2184 */ 2185 /* 6 extra bytes for /%recv */ 2186 char recvname[ZFS_MAX_DATASET_NAME_LEN + 6]; 2187 dsl_dataset_t *recv_ds; 2188 dsl_dataset_name(ds, recvname); 2189 if (strlcat(recvname, "/", sizeof (recvname)) < 2190 sizeof (recvname) && 2191 strlcat(recvname, recv_clone_name, sizeof (recvname)) < 2192 sizeof (recvname) && 2193 dsl_dataset_hold(dp, recvname, FTAG, &recv_ds) == 0) { 2194 get_receive_resume_stats(recv_ds, nv); 2195 dsl_dataset_rele(recv_ds, FTAG); 2196 } 2197 } 2198 } 2199 2200 void 2201 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 2202 { 2203 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2204 ASSERT(dsl_pool_config_held(dp)); 2205 2206 stat->dds_creation_txg = dsl_get_creationtxg(ds); 2207 stat->dds_inconsistent = dsl_get_inconsistent(ds); 2208 stat->dds_guid = dsl_get_guid(ds); 2209 stat->dds_origin[0] = '\0'; 2210 if (ds->ds_is_snapshot) { 2211 stat->dds_is_snapshot = B_TRUE; 2212 stat->dds_num_clones = dsl_get_numclones(ds); 2213 } else { 2214 stat->dds_is_snapshot = B_FALSE; 2215 stat->dds_num_clones = 0; 2216 2217 if (dsl_dir_is_clone(ds->ds_dir)) { 2218 dsl_dir_get_origin(ds->ds_dir, stat->dds_origin); 2219 } 2220 } 2221 } 2222 2223 uint64_t 2224 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 2225 { 2226 return (ds->ds_fsid_guid); 2227 } 2228 2229 void 2230 dsl_dataset_space(dsl_dataset_t *ds, 2231 uint64_t *refdbytesp, uint64_t *availbytesp, 2232 uint64_t *usedobjsp, uint64_t *availobjsp) 2233 { 2234 *refdbytesp = dsl_dataset_phys(ds)->ds_referenced_bytes; 2235 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 2236 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) 2237 *availbytesp += 2238 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes; 2239 if (ds->ds_quota != 0) { 2240 /* 2241 * Adjust available bytes according to refquota 2242 */ 2243 if (*refdbytesp < ds->ds_quota) 2244 *availbytesp = MIN(*availbytesp, 2245 ds->ds_quota - *refdbytesp); 2246 else 2247 *availbytesp = 0; 2248 } 2249 rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); 2250 *usedobjsp = BP_GET_FILL(&dsl_dataset_phys(ds)->ds_bp); 2251 rrw_exit(&ds->ds_bp_rwlock, FTAG); 2252 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 2253 } 2254 2255 boolean_t 2256 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap) 2257 { 2258 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2259 uint64_t birth; 2260 2261 ASSERT(dsl_pool_config_held(dp)); 2262 if (snap == NULL) 2263 return (B_FALSE); 2264 rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); 2265 birth = dsl_dataset_get_blkptr(ds)->blk_birth; 2266 rrw_exit(&ds->ds_bp_rwlock, FTAG); 2267 if (birth > dsl_dataset_phys(snap)->ds_creation_txg) { 2268 objset_t *os, *os_snap; 2269 /* 2270 * It may be that only the ZIL differs, because it was 2271 * reset in the head. Don't count that as being 2272 * modified. 2273 */ 2274 if (dmu_objset_from_ds(ds, &os) != 0) 2275 return (B_TRUE); 2276 if (dmu_objset_from_ds(snap, &os_snap) != 0) 2277 return (B_TRUE); 2278 return (bcmp(&os->os_phys->os_meta_dnode, 2279 &os_snap->os_phys->os_meta_dnode, 2280 sizeof (os->os_phys->os_meta_dnode)) != 0); 2281 } 2282 return (B_FALSE); 2283 } 2284 2285 typedef struct dsl_dataset_rename_snapshot_arg { 2286 const char *ddrsa_fsname; 2287 const char *ddrsa_oldsnapname; 2288 const char *ddrsa_newsnapname; 2289 boolean_t ddrsa_recursive; 2290 dmu_tx_t *ddrsa_tx; 2291 } dsl_dataset_rename_snapshot_arg_t; 2292 2293 /* ARGSUSED */ 2294 static int 2295 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp, 2296 dsl_dataset_t *hds, void *arg) 2297 { 2298 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2299 int error; 2300 uint64_t val; 2301 2302 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2303 if (error != 0) { 2304 /* ignore nonexistent snapshots */ 2305 return (error == ENOENT ? 0 : error); 2306 } 2307 2308 /* new name should not exist */ 2309 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val); 2310 if (error == 0) 2311 error = SET_ERROR(EEXIST); 2312 else if (error == ENOENT) 2313 error = 0; 2314 2315 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2316 if (dsl_dir_namelen(hds->ds_dir) + 1 + 2317 strlen(ddrsa->ddrsa_newsnapname) >= ZFS_MAX_DATASET_NAME_LEN) 2318 error = SET_ERROR(ENAMETOOLONG); 2319 2320 return (error); 2321 } 2322 2323 static int 2324 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx) 2325 { 2326 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2327 dsl_pool_t *dp = dmu_tx_pool(tx); 2328 dsl_dataset_t *hds; 2329 int error; 2330 2331 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds); 2332 if (error != 0) 2333 return (error); 2334 2335 if (ddrsa->ddrsa_recursive) { 2336 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2337 dsl_dataset_rename_snapshot_check_impl, ddrsa, 2338 DS_FIND_CHILDREN); 2339 } else { 2340 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa); 2341 } 2342 dsl_dataset_rele(hds, FTAG); 2343 return (error); 2344 } 2345 2346 static int 2347 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp, 2348 dsl_dataset_t *hds, void *arg) 2349 { 2350 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2351 dsl_dataset_t *ds; 2352 uint64_t val; 2353 dmu_tx_t *tx = ddrsa->ddrsa_tx; 2354 int error; 2355 2356 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val); 2357 ASSERT(error == 0 || error == ENOENT); 2358 if (error == ENOENT) { 2359 /* ignore nonexistent snapshots */ 2360 return (0); 2361 } 2362 2363 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds)); 2364 2365 /* log before we change the name */ 2366 spa_history_log_internal_ds(ds, "rename", tx, 2367 "-> @%s", ddrsa->ddrsa_newsnapname); 2368 2369 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx, 2370 B_FALSE)); 2371 mutex_enter(&ds->ds_lock); 2372 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname); 2373 mutex_exit(&ds->ds_lock); 2374 VERIFY0(zap_add(dp->dp_meta_objset, 2375 dsl_dataset_phys(hds)->ds_snapnames_zapobj, 2376 ds->ds_snapname, 8, 1, &ds->ds_object, tx)); 2377 2378 dsl_dataset_rele(ds, FTAG); 2379 return (0); 2380 } 2381 2382 static void 2383 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx) 2384 { 2385 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg; 2386 dsl_pool_t *dp = dmu_tx_pool(tx); 2387 dsl_dataset_t *hds; 2388 2389 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds)); 2390 ddrsa->ddrsa_tx = tx; 2391 if (ddrsa->ddrsa_recursive) { 2392 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object, 2393 dsl_dataset_rename_snapshot_sync_impl, ddrsa, 2394 DS_FIND_CHILDREN)); 2395 } else { 2396 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa)); 2397 } 2398 dsl_dataset_rele(hds, FTAG); 2399 } 2400 2401 int 2402 dsl_dataset_rename_snapshot(const char *fsname, 2403 const char *oldsnapname, const char *newsnapname, boolean_t recursive) 2404 { 2405 dsl_dataset_rename_snapshot_arg_t ddrsa; 2406 2407 ddrsa.ddrsa_fsname = fsname; 2408 ddrsa.ddrsa_oldsnapname = oldsnapname; 2409 ddrsa.ddrsa_newsnapname = newsnapname; 2410 ddrsa.ddrsa_recursive = recursive; 2411 2412 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check, 2413 dsl_dataset_rename_snapshot_sync, &ddrsa, 2414 1, ZFS_SPACE_CHECK_RESERVED)); 2415 } 2416 2417 /* 2418 * If we're doing an ownership handoff, we need to make sure that there is 2419 * only one long hold on the dataset. We're not allowed to change anything here 2420 * so we don't permanently release the long hold or regular hold here. We want 2421 * to do this only when syncing to avoid the dataset unexpectedly going away 2422 * when we release the long hold. 2423 */ 2424 static int 2425 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx) 2426 { 2427 boolean_t held; 2428 2429 if (!dmu_tx_is_syncing(tx)) 2430 return (0); 2431 2432 if (owner != NULL) { 2433 VERIFY3P(ds->ds_owner, ==, owner); 2434 dsl_dataset_long_rele(ds, owner); 2435 } 2436 2437 held = dsl_dataset_long_held(ds); 2438 2439 if (owner != NULL) 2440 dsl_dataset_long_hold(ds, owner); 2441 2442 if (held) 2443 return (SET_ERROR(EBUSY)); 2444 2445 return (0); 2446 } 2447 2448 int 2449 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx) 2450 { 2451 dsl_dataset_rollback_arg_t *ddra = arg; 2452 dsl_pool_t *dp = dmu_tx_pool(tx); 2453 dsl_dataset_t *ds; 2454 int64_t unused_refres_delta; 2455 int error; 2456 2457 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds); 2458 if (error != 0) 2459 return (error); 2460 2461 /* must not be a snapshot */ 2462 if (ds->ds_is_snapshot) { 2463 dsl_dataset_rele(ds, FTAG); 2464 return (SET_ERROR(EINVAL)); 2465 } 2466 2467 /* must have a most recent snapshot */ 2468 if (dsl_dataset_phys(ds)->ds_prev_snap_txg < TXG_INITIAL) { 2469 dsl_dataset_rele(ds, FTAG); 2470 return (SET_ERROR(EINVAL)); 2471 } 2472 2473 /* 2474 * No rollback to a snapshot created in the current txg, because 2475 * the rollback may dirty the dataset and create blocks that are 2476 * not reachable from the rootbp while having a birth txg that 2477 * falls into the snapshot's range. 2478 */ 2479 if (dmu_tx_is_syncing(tx) && 2480 dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg) { 2481 dsl_dataset_rele(ds, FTAG); 2482 return (SET_ERROR(EAGAIN)); 2483 } 2484 2485 /* 2486 * If the expected target snapshot is specified, then check that 2487 * the latest snapshot is it. 2488 */ 2489 if (ddra->ddra_tosnap != NULL) { 2490 char namebuf[ZFS_MAX_DATASET_NAME_LEN]; 2491 2492 dsl_dataset_name(ds->ds_prev, namebuf); 2493 if (strcmp(namebuf, ddra->ddra_tosnap) != 0) 2494 return (SET_ERROR(EXDEV)); 2495 } 2496 2497 /* must not have any bookmarks after the most recent snapshot */ 2498 nvlist_t *proprequest = fnvlist_alloc(); 2499 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2500 nvlist_t *bookmarks = fnvlist_alloc(); 2501 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks); 2502 fnvlist_free(proprequest); 2503 if (error != 0) 2504 return (error); 2505 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL); 2506 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) { 2507 nvlist_t *valuenv = 2508 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair), 2509 zfs_prop_to_name(ZFS_PROP_CREATETXG)); 2510 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value"); 2511 if (createtxg > dsl_dataset_phys(ds)->ds_prev_snap_txg) { 2512 fnvlist_free(bookmarks); 2513 dsl_dataset_rele(ds, FTAG); 2514 return (SET_ERROR(EEXIST)); 2515 } 2516 } 2517 fnvlist_free(bookmarks); 2518 2519 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx); 2520 if (error != 0) { 2521 dsl_dataset_rele(ds, FTAG); 2522 return (error); 2523 } 2524 2525 /* 2526 * Check if the snap we are rolling back to uses more than 2527 * the refquota. 2528 */ 2529 if (ds->ds_quota != 0 && 2530 dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes > ds->ds_quota) { 2531 dsl_dataset_rele(ds, FTAG); 2532 return (SET_ERROR(EDQUOT)); 2533 } 2534 2535 /* 2536 * When we do the clone swap, we will temporarily use more space 2537 * due to the refreservation (the head will no longer have any 2538 * unique space, so the entire amount of the refreservation will need 2539 * to be free). We will immediately destroy the clone, freeing 2540 * this space, but the freeing happens over many txg's. 2541 */ 2542 unused_refres_delta = (int64_t)MIN(ds->ds_reserved, 2543 dsl_dataset_phys(ds)->ds_unique_bytes); 2544 2545 if (unused_refres_delta > 0 && 2546 unused_refres_delta > 2547 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) { 2548 dsl_dataset_rele(ds, FTAG); 2549 return (SET_ERROR(ENOSPC)); 2550 } 2551 2552 dsl_dataset_rele(ds, FTAG); 2553 return (0); 2554 } 2555 2556 void 2557 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx) 2558 { 2559 dsl_dataset_rollback_arg_t *ddra = arg; 2560 dsl_pool_t *dp = dmu_tx_pool(tx); 2561 dsl_dataset_t *ds, *clone; 2562 uint64_t cloneobj; 2563 char namebuf[ZFS_MAX_DATASET_NAME_LEN]; 2564 2565 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds)); 2566 2567 dsl_dataset_name(ds->ds_prev, namebuf); 2568 fnvlist_add_string(ddra->ddra_result, "target", namebuf); 2569 2570 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback", 2571 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx); 2572 2573 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone)); 2574 2575 dsl_dataset_clone_swap_sync_impl(clone, ds, tx); 2576 dsl_dataset_zero_zil(ds, tx); 2577 2578 dsl_destroy_head_sync_impl(clone, tx); 2579 2580 dsl_dataset_rele(clone, FTAG); 2581 dsl_dataset_rele(ds, FTAG); 2582 } 2583 2584 /* 2585 * Rolls back the given filesystem or volume to the most recent snapshot. 2586 * The name of the most recent snapshot will be returned under key "target" 2587 * in the result nvlist. 2588 * 2589 * If owner != NULL: 2590 * - The existing dataset MUST be owned by the specified owner at entry 2591 * - Upon return, dataset will still be held by the same owner, whether we 2592 * succeed or not. 2593 * 2594 * This mode is required any time the existing filesystem is mounted. See 2595 * notes above zfs_suspend_fs() for further details. 2596 */ 2597 int 2598 dsl_dataset_rollback(const char *fsname, const char *tosnap, void *owner, 2599 nvlist_t *result) 2600 { 2601 dsl_dataset_rollback_arg_t ddra; 2602 2603 ddra.ddra_fsname = fsname; 2604 ddra.ddra_tosnap = tosnap; 2605 ddra.ddra_owner = owner; 2606 ddra.ddra_result = result; 2607 2608 return (dsl_sync_task(fsname, dsl_dataset_rollback_check, 2609 dsl_dataset_rollback_sync, &ddra, 2610 1, ZFS_SPACE_CHECK_RESERVED)); 2611 } 2612 2613 struct promotenode { 2614 list_node_t link; 2615 dsl_dataset_t *ds; 2616 }; 2617 2618 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2619 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, 2620 void *tag); 2621 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag); 2622 2623 int 2624 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx) 2625 { 2626 dsl_dataset_promote_arg_t *ddpa = arg; 2627 dsl_pool_t *dp = dmu_tx_pool(tx); 2628 dsl_dataset_t *hds; 2629 struct promotenode *snap; 2630 dsl_dataset_t *origin_ds; 2631 int err; 2632 uint64_t unused; 2633 uint64_t ss_mv_cnt; 2634 size_t max_snap_len; 2635 boolean_t conflicting_snaps; 2636 2637 err = promote_hold(ddpa, dp, FTAG); 2638 if (err != 0) 2639 return (err); 2640 2641 hds = ddpa->ddpa_clone; 2642 snap = list_head(&ddpa->shared_snaps); 2643 origin_ds = snap->ds; 2644 max_snap_len = MAXNAMELEN - strlen(ddpa->ddpa_clonename) - 1; 2645 2646 snap = list_head(&ddpa->origin_snaps); 2647 2648 if (dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE) { 2649 promote_rele(ddpa, FTAG); 2650 return (SET_ERROR(EXDEV)); 2651 } 2652 2653 /* 2654 * Compute and check the amount of space to transfer. Since this is 2655 * so expensive, don't do the preliminary check. 2656 */ 2657 if (!dmu_tx_is_syncing(tx)) { 2658 promote_rele(ddpa, FTAG); 2659 return (0); 2660 } 2661 2662 /* compute origin's new unique space */ 2663 snap = list_tail(&ddpa->clone_snaps); 2664 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2665 origin_ds->ds_object); 2666 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 2667 dsl_dataset_phys(origin_ds)->ds_prev_snap_txg, UINT64_MAX, 2668 &ddpa->unique, &unused, &unused); 2669 2670 /* 2671 * Walk the snapshots that we are moving 2672 * 2673 * Compute space to transfer. Consider the incremental changes 2674 * to used by each snapshot: 2675 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2676 * So each snapshot gave birth to: 2677 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2678 * So a sequence would look like: 2679 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2680 * Which simplifies to: 2681 * uN + kN + kN-1 + ... + k1 + k0 2682 * Note however, if we stop before we reach the ORIGIN we get: 2683 * uN + kN + kN-1 + ... + kM - uM-1 2684 */ 2685 conflicting_snaps = B_FALSE; 2686 ss_mv_cnt = 0; 2687 ddpa->used = dsl_dataset_phys(origin_ds)->ds_referenced_bytes; 2688 ddpa->comp = dsl_dataset_phys(origin_ds)->ds_compressed_bytes; 2689 ddpa->uncomp = dsl_dataset_phys(origin_ds)->ds_uncompressed_bytes; 2690 for (snap = list_head(&ddpa->shared_snaps); snap; 2691 snap = list_next(&ddpa->shared_snaps, snap)) { 2692 uint64_t val, dlused, dlcomp, dluncomp; 2693 dsl_dataset_t *ds = snap->ds; 2694 2695 ss_mv_cnt++; 2696 2697 /* 2698 * If there are long holds, we won't be able to evict 2699 * the objset. 2700 */ 2701 if (dsl_dataset_long_held(ds)) { 2702 err = SET_ERROR(EBUSY); 2703 goto out; 2704 } 2705 2706 /* Check that the snapshot name does not conflict */ 2707 VERIFY0(dsl_dataset_get_snapname(ds)); 2708 if (strlen(ds->ds_snapname) >= max_snap_len) { 2709 err = SET_ERROR(ENAMETOOLONG); 2710 goto out; 2711 } 2712 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2713 if (err == 0) { 2714 fnvlist_add_boolean(ddpa->err_ds, 2715 snap->ds->ds_snapname); 2716 conflicting_snaps = B_TRUE; 2717 } else if (err != ENOENT) { 2718 goto out; 2719 } 2720 2721 /* The very first snapshot does not have a deadlist */ 2722 if (dsl_dataset_phys(ds)->ds_prev_snap_obj == 0) 2723 continue; 2724 2725 dsl_deadlist_space(&ds->ds_deadlist, 2726 &dlused, &dlcomp, &dluncomp); 2727 ddpa->used += dlused; 2728 ddpa->comp += dlcomp; 2729 ddpa->uncomp += dluncomp; 2730 } 2731 2732 /* 2733 * In order to return the full list of conflicting snapshots, we check 2734 * whether there was a conflict after traversing all of them. 2735 */ 2736 if (conflicting_snaps) { 2737 err = SET_ERROR(EEXIST); 2738 goto out; 2739 } 2740 2741 /* 2742 * If we are a clone of a clone then we never reached ORIGIN, 2743 * so we need to subtract out the clone origin's used space. 2744 */ 2745 if (ddpa->origin_origin) { 2746 ddpa->used -= 2747 dsl_dataset_phys(ddpa->origin_origin)->ds_referenced_bytes; 2748 ddpa->comp -= 2749 dsl_dataset_phys(ddpa->origin_origin)->ds_compressed_bytes; 2750 ddpa->uncomp -= 2751 dsl_dataset_phys(ddpa->origin_origin)-> 2752 ds_uncompressed_bytes; 2753 } 2754 2755 /* Check that there is enough space and limit headroom here */ 2756 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2757 0, ss_mv_cnt, ddpa->used, ddpa->cr); 2758 if (err != 0) 2759 goto out; 2760 2761 /* 2762 * Compute the amounts of space that will be used by snapshots 2763 * after the promotion (for both origin and clone). For each, 2764 * it is the amount of space that will be on all of their 2765 * deadlists (that was not born before their new origin). 2766 */ 2767 if (dsl_dir_phys(hds->ds_dir)->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2768 uint64_t space; 2769 2770 /* 2771 * Note, typically this will not be a clone of a clone, 2772 * so dd_origin_txg will be < TXG_INITIAL, so 2773 * these snaplist_space() -> dsl_deadlist_space_range() 2774 * calls will be fast because they do not have to 2775 * iterate over all bps. 2776 */ 2777 snap = list_head(&ddpa->origin_snaps); 2778 err = snaplist_space(&ddpa->shared_snaps, 2779 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap); 2780 if (err != 0) 2781 goto out; 2782 2783 err = snaplist_space(&ddpa->clone_snaps, 2784 snap->ds->ds_dir->dd_origin_txg, &space); 2785 if (err != 0) 2786 goto out; 2787 ddpa->cloneusedsnap += space; 2788 } 2789 if (dsl_dir_phys(origin_ds->ds_dir)->dd_flags & 2790 DD_FLAG_USED_BREAKDOWN) { 2791 err = snaplist_space(&ddpa->origin_snaps, 2792 dsl_dataset_phys(origin_ds)->ds_creation_txg, 2793 &ddpa->originusedsnap); 2794 if (err != 0) 2795 goto out; 2796 } 2797 2798 out: 2799 promote_rele(ddpa, FTAG); 2800 return (err); 2801 } 2802 2803 void 2804 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx) 2805 { 2806 dsl_dataset_promote_arg_t *ddpa = arg; 2807 dsl_pool_t *dp = dmu_tx_pool(tx); 2808 dsl_dataset_t *hds; 2809 struct promotenode *snap; 2810 dsl_dataset_t *origin_ds; 2811 dsl_dataset_t *origin_head; 2812 dsl_dir_t *dd; 2813 dsl_dir_t *odd = NULL; 2814 uint64_t oldnext_obj; 2815 int64_t delta; 2816 2817 VERIFY0(promote_hold(ddpa, dp, FTAG)); 2818 hds = ddpa->ddpa_clone; 2819 2820 ASSERT0(dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE); 2821 2822 snap = list_head(&ddpa->shared_snaps); 2823 origin_ds = snap->ds; 2824 dd = hds->ds_dir; 2825 2826 snap = list_head(&ddpa->origin_snaps); 2827 origin_head = snap->ds; 2828 2829 /* 2830 * We need to explicitly open odd, since origin_ds's dd will be 2831 * changing. 2832 */ 2833 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object, 2834 NULL, FTAG, &odd)); 2835 2836 /* change origin's next snap */ 2837 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2838 oldnext_obj = dsl_dataset_phys(origin_ds)->ds_next_snap_obj; 2839 snap = list_tail(&ddpa->clone_snaps); 2840 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==, 2841 origin_ds->ds_object); 2842 dsl_dataset_phys(origin_ds)->ds_next_snap_obj = snap->ds->ds_object; 2843 2844 /* change the origin's next clone */ 2845 if (dsl_dataset_phys(origin_ds)->ds_next_clones_obj) { 2846 dsl_dataset_remove_from_next_clones(origin_ds, 2847 snap->ds->ds_object, tx); 2848 VERIFY0(zap_add_int(dp->dp_meta_objset, 2849 dsl_dataset_phys(origin_ds)->ds_next_clones_obj, 2850 oldnext_obj, tx)); 2851 } 2852 2853 /* change origin */ 2854 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2855 ASSERT3U(dsl_dir_phys(dd)->dd_origin_obj, ==, origin_ds->ds_object); 2856 dsl_dir_phys(dd)->dd_origin_obj = dsl_dir_phys(odd)->dd_origin_obj; 2857 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg; 2858 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2859 dsl_dir_phys(odd)->dd_origin_obj = origin_ds->ds_object; 2860 origin_head->ds_dir->dd_origin_txg = 2861 dsl_dataset_phys(origin_ds)->ds_creation_txg; 2862 2863 /* change dd_clone entries */ 2864 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2865 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2866 dsl_dir_phys(odd)->dd_clones, hds->ds_object, tx)); 2867 VERIFY0(zap_add_int(dp->dp_meta_objset, 2868 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2869 hds->ds_object, tx)); 2870 2871 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2872 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones, 2873 origin_head->ds_object, tx)); 2874 if (dsl_dir_phys(dd)->dd_clones == 0) { 2875 dsl_dir_phys(dd)->dd_clones = 2876 zap_create(dp->dp_meta_objset, DMU_OT_DSL_CLONES, 2877 DMU_OT_NONE, 0, tx); 2878 } 2879 VERIFY0(zap_add_int(dp->dp_meta_objset, 2880 dsl_dir_phys(dd)->dd_clones, origin_head->ds_object, tx)); 2881 } 2882 2883 /* move snapshots to this dir */ 2884 for (snap = list_head(&ddpa->shared_snaps); snap; 2885 snap = list_next(&ddpa->shared_snaps, snap)) { 2886 dsl_dataset_t *ds = snap->ds; 2887 2888 /* 2889 * Property callbacks are registered to a particular 2890 * dsl_dir. Since ours is changing, evict the objset 2891 * so that they will be unregistered from the old dsl_dir. 2892 */ 2893 if (ds->ds_objset) { 2894 dmu_objset_evict(ds->ds_objset); 2895 ds->ds_objset = NULL; 2896 } 2897 2898 /* move snap name entry */ 2899 VERIFY0(dsl_dataset_get_snapname(ds)); 2900 VERIFY0(dsl_dataset_snap_remove(origin_head, 2901 ds->ds_snapname, tx, B_TRUE)); 2902 VERIFY0(zap_add(dp->dp_meta_objset, 2903 dsl_dataset_phys(hds)->ds_snapnames_zapobj, ds->ds_snapname, 2904 8, 1, &ds->ds_object, tx)); 2905 dsl_fs_ss_count_adjust(hds->ds_dir, 1, 2906 DD_FIELD_SNAPSHOT_COUNT, tx); 2907 2908 /* change containing dsl_dir */ 2909 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2910 ASSERT3U(dsl_dataset_phys(ds)->ds_dir_obj, ==, odd->dd_object); 2911 dsl_dataset_phys(ds)->ds_dir_obj = dd->dd_object; 2912 ASSERT3P(ds->ds_dir, ==, odd); 2913 dsl_dir_rele(ds->ds_dir, ds); 2914 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object, 2915 NULL, ds, &ds->ds_dir)); 2916 2917 /* move any clone references */ 2918 if (dsl_dataset_phys(ds)->ds_next_clones_obj && 2919 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { 2920 zap_cursor_t zc; 2921 zap_attribute_t za; 2922 2923 for (zap_cursor_init(&zc, dp->dp_meta_objset, 2924 dsl_dataset_phys(ds)->ds_next_clones_obj); 2925 zap_cursor_retrieve(&zc, &za) == 0; 2926 zap_cursor_advance(&zc)) { 2927 dsl_dataset_t *cnds; 2928 uint64_t o; 2929 2930 if (za.za_first_integer == oldnext_obj) { 2931 /* 2932 * We've already moved the 2933 * origin's reference. 2934 */ 2935 continue; 2936 } 2937 2938 VERIFY0(dsl_dataset_hold_obj(dp, 2939 za.za_first_integer, FTAG, &cnds)); 2940 o = dsl_dir_phys(cnds->ds_dir)-> 2941 dd_head_dataset_obj; 2942 2943 VERIFY0(zap_remove_int(dp->dp_meta_objset, 2944 dsl_dir_phys(odd)->dd_clones, o, tx)); 2945 VERIFY0(zap_add_int(dp->dp_meta_objset, 2946 dsl_dir_phys(dd)->dd_clones, o, tx)); 2947 dsl_dataset_rele(cnds, FTAG); 2948 } 2949 zap_cursor_fini(&zc); 2950 } 2951 2952 ASSERT(!dsl_prop_hascb(ds)); 2953 } 2954 2955 /* 2956 * Change space accounting. 2957 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2958 * both be valid, or both be 0 (resulting in delta == 0). This 2959 * is true for each of {clone,origin} independently. 2960 */ 2961 2962 delta = ddpa->cloneusedsnap - 2963 dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_SNAP]; 2964 ASSERT3S(delta, >=, 0); 2965 ASSERT3U(ddpa->used, >=, delta); 2966 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2967 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2968 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx); 2969 2970 delta = ddpa->originusedsnap - 2971 dsl_dir_phys(odd)->dd_used_breakdown[DD_USED_SNAP]; 2972 ASSERT3S(delta, <=, 0); 2973 ASSERT3U(ddpa->used, >=, -delta); 2974 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2975 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2976 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx); 2977 2978 dsl_dataset_phys(origin_ds)->ds_unique_bytes = ddpa->unique; 2979 2980 /* log history record */ 2981 spa_history_log_internal_ds(hds, "promote", tx, ""); 2982 2983 dsl_dir_rele(odd, FTAG); 2984 promote_rele(ddpa, FTAG); 2985 } 2986 2987 /* 2988 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2989 * (exclusive) and last_obj (inclusive). The list will be in reverse 2990 * order (last_obj will be the list_head()). If first_obj == 0, do all 2991 * snapshots back to this dataset's origin. 2992 */ 2993 static int 2994 snaplist_make(dsl_pool_t *dp, 2995 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag) 2996 { 2997 uint64_t obj = last_obj; 2998 2999 list_create(l, sizeof (struct promotenode), 3000 offsetof(struct promotenode, link)); 3001 3002 while (obj != first_obj) { 3003 dsl_dataset_t *ds; 3004 struct promotenode *snap; 3005 int err; 3006 3007 err = dsl_dataset_hold_obj(dp, obj, tag, &ds); 3008 ASSERT(err != ENOENT); 3009 if (err != 0) 3010 return (err); 3011 3012 if (first_obj == 0) 3013 first_obj = dsl_dir_phys(ds->ds_dir)->dd_origin_obj; 3014 3015 snap = kmem_alloc(sizeof (*snap), KM_SLEEP); 3016 snap->ds = ds; 3017 list_insert_tail(l, snap); 3018 obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 3019 } 3020 3021 return (0); 3022 } 3023 3024 static int 3025 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 3026 { 3027 struct promotenode *snap; 3028 3029 *spacep = 0; 3030 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 3031 uint64_t used, comp, uncomp; 3032 dsl_deadlist_space_range(&snap->ds->ds_deadlist, 3033 mintxg, UINT64_MAX, &used, &comp, &uncomp); 3034 *spacep += used; 3035 } 3036 return (0); 3037 } 3038 3039 static void 3040 snaplist_destroy(list_t *l, void *tag) 3041 { 3042 struct promotenode *snap; 3043 3044 if (l == NULL || !list_link_active(&l->list_head)) 3045 return; 3046 3047 while ((snap = list_tail(l)) != NULL) { 3048 list_remove(l, snap); 3049 dsl_dataset_rele(snap->ds, tag); 3050 kmem_free(snap, sizeof (*snap)); 3051 } 3052 list_destroy(l); 3053 } 3054 3055 static int 3056 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag) 3057 { 3058 int error; 3059 dsl_dir_t *dd; 3060 struct promotenode *snap; 3061 3062 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag, 3063 &ddpa->ddpa_clone); 3064 if (error != 0) 3065 return (error); 3066 dd = ddpa->ddpa_clone->ds_dir; 3067 3068 if (ddpa->ddpa_clone->ds_is_snapshot || 3069 !dsl_dir_is_clone(dd)) { 3070 dsl_dataset_rele(ddpa->ddpa_clone, tag); 3071 return (SET_ERROR(EINVAL)); 3072 } 3073 3074 error = snaplist_make(dp, 0, dsl_dir_phys(dd)->dd_origin_obj, 3075 &ddpa->shared_snaps, tag); 3076 if (error != 0) 3077 goto out; 3078 3079 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object, 3080 &ddpa->clone_snaps, tag); 3081 if (error != 0) 3082 goto out; 3083 3084 snap = list_head(&ddpa->shared_snaps); 3085 ASSERT3U(snap->ds->ds_object, ==, dsl_dir_phys(dd)->dd_origin_obj); 3086 error = snaplist_make(dp, dsl_dir_phys(dd)->dd_origin_obj, 3087 dsl_dir_phys(snap->ds->ds_dir)->dd_head_dataset_obj, 3088 &ddpa->origin_snaps, tag); 3089 if (error != 0) 3090 goto out; 3091 3092 if (dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj != 0) { 3093 error = dsl_dataset_hold_obj(dp, 3094 dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj, 3095 tag, &ddpa->origin_origin); 3096 if (error != 0) 3097 goto out; 3098 } 3099 out: 3100 if (error != 0) 3101 promote_rele(ddpa, tag); 3102 return (error); 3103 } 3104 3105 static void 3106 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag) 3107 { 3108 snaplist_destroy(&ddpa->shared_snaps, tag); 3109 snaplist_destroy(&ddpa->clone_snaps, tag); 3110 snaplist_destroy(&ddpa->origin_snaps, tag); 3111 if (ddpa->origin_origin != NULL) 3112 dsl_dataset_rele(ddpa->origin_origin, tag); 3113 dsl_dataset_rele(ddpa->ddpa_clone, tag); 3114 } 3115 3116 /* 3117 * Promote a clone. 3118 * 3119 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled 3120 * in with the name. (It must be at least ZFS_MAX_DATASET_NAME_LEN bytes long.) 3121 */ 3122 int 3123 dsl_dataset_promote(const char *name, char *conflsnap) 3124 { 3125 dsl_dataset_promote_arg_t ddpa = { 0 }; 3126 uint64_t numsnaps; 3127 int error; 3128 nvpair_t *snap_pair; 3129 objset_t *os; 3130 3131 /* 3132 * We will modify space proportional to the number of 3133 * snapshots. Compute numsnaps. 3134 */ 3135 error = dmu_objset_hold(name, FTAG, &os); 3136 if (error != 0) 3137 return (error); 3138 error = zap_count(dmu_objset_pool(os)->dp_meta_objset, 3139 dsl_dataset_phys(dmu_objset_ds(os))->ds_snapnames_zapobj, 3140 &numsnaps); 3141 dmu_objset_rele(os, FTAG); 3142 if (error != 0) 3143 return (error); 3144 3145 ddpa.ddpa_clonename = name; 3146 ddpa.err_ds = fnvlist_alloc(); 3147 ddpa.cr = CRED(); 3148 3149 error = dsl_sync_task(name, dsl_dataset_promote_check, 3150 dsl_dataset_promote_sync, &ddpa, 3151 2 + numsnaps, ZFS_SPACE_CHECK_RESERVED); 3152 3153 /* 3154 * Return the first conflicting snapshot found. 3155 */ 3156 snap_pair = nvlist_next_nvpair(ddpa.err_ds, NULL); 3157 if (snap_pair != NULL && conflsnap != NULL) 3158 (void) strcpy(conflsnap, nvpair_name(snap_pair)); 3159 3160 fnvlist_free(ddpa.err_ds); 3161 return (error); 3162 } 3163 3164 int 3165 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone, 3166 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx) 3167 { 3168 /* 3169 * "slack" factor for received datasets with refquota set on them. 3170 * See the bottom of this function for details on its use. 3171 */ 3172 uint64_t refquota_slack = DMU_MAX_ACCESS * spa_asize_inflation; 3173 int64_t unused_refres_delta; 3174 3175 /* they should both be heads */ 3176 if (clone->ds_is_snapshot || 3177 origin_head->ds_is_snapshot) 3178 return (SET_ERROR(EINVAL)); 3179 3180 /* if we are not forcing, the branch point should be just before them */ 3181 if (!force && clone->ds_prev != origin_head->ds_prev) 3182 return (SET_ERROR(EINVAL)); 3183 3184 /* clone should be the clone (unless they are unrelated) */ 3185 if (clone->ds_prev != NULL && 3186 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap && 3187 origin_head->ds_dir != clone->ds_prev->ds_dir) 3188 return (SET_ERROR(EINVAL)); 3189 3190 /* the clone should be a child of the origin */ 3191 if (clone->ds_dir->dd_parent != origin_head->ds_dir) 3192 return (SET_ERROR(EINVAL)); 3193 3194 /* origin_head shouldn't be modified unless 'force' */ 3195 if (!force && 3196 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev)) 3197 return (SET_ERROR(ETXTBSY)); 3198 3199 /* origin_head should have no long holds (e.g. is not mounted) */ 3200 if (dsl_dataset_handoff_check(origin_head, owner, tx)) 3201 return (SET_ERROR(EBUSY)); 3202 3203 /* check amount of any unconsumed refreservation */ 3204 unused_refres_delta = 3205 (int64_t)MIN(origin_head->ds_reserved, 3206 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 3207 (int64_t)MIN(origin_head->ds_reserved, 3208 dsl_dataset_phys(clone)->ds_unique_bytes); 3209 3210 if (unused_refres_delta > 0 && 3211 unused_refres_delta > 3212 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE)) 3213 return (SET_ERROR(ENOSPC)); 3214 3215 /* 3216 * The clone can't be too much over the head's refquota. 3217 * 3218 * To ensure that the entire refquota can be used, we allow one 3219 * transaction to exceed the the refquota. Therefore, this check 3220 * needs to also allow for the space referenced to be more than the 3221 * refquota. The maximum amount of space that one transaction can use 3222 * on disk is DMU_MAX_ACCESS * spa_asize_inflation. Allowing this 3223 * overage ensures that we are able to receive a filesystem that 3224 * exceeds the refquota on the source system. 3225 * 3226 * So that overage is the refquota_slack we use below. 3227 */ 3228 if (origin_head->ds_quota != 0 && 3229 dsl_dataset_phys(clone)->ds_referenced_bytes > 3230 origin_head->ds_quota + refquota_slack) 3231 return (SET_ERROR(EDQUOT)); 3232 3233 return (0); 3234 } 3235 3236 void 3237 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone, 3238 dsl_dataset_t *origin_head, dmu_tx_t *tx) 3239 { 3240 dsl_pool_t *dp = dmu_tx_pool(tx); 3241 int64_t unused_refres_delta; 3242 3243 ASSERT(clone->ds_reserved == 0); 3244 /* 3245 * NOTE: On DEBUG kernels there could be a race between this and 3246 * the check function if spa_asize_inflation is adjusted... 3247 */ 3248 ASSERT(origin_head->ds_quota == 0 || 3249 dsl_dataset_phys(clone)->ds_unique_bytes <= origin_head->ds_quota + 3250 DMU_MAX_ACCESS * spa_asize_inflation); 3251 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev); 3252 3253 /* 3254 * Swap per-dataset feature flags. 3255 */ 3256 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { 3257 if (!(spa_feature_table[f].fi_flags & 3258 ZFEATURE_FLAG_PER_DATASET)) { 3259 ASSERT(!clone->ds_feature_inuse[f]); 3260 ASSERT(!origin_head->ds_feature_inuse[f]); 3261 continue; 3262 } 3263 3264 boolean_t clone_inuse = clone->ds_feature_inuse[f]; 3265 boolean_t origin_head_inuse = origin_head->ds_feature_inuse[f]; 3266 3267 if (clone_inuse) { 3268 dsl_dataset_deactivate_feature(clone->ds_object, f, tx); 3269 clone->ds_feature_inuse[f] = B_FALSE; 3270 } 3271 if (origin_head_inuse) { 3272 dsl_dataset_deactivate_feature(origin_head->ds_object, 3273 f, tx); 3274 origin_head->ds_feature_inuse[f] = B_FALSE; 3275 } 3276 if (clone_inuse) { 3277 dsl_dataset_activate_feature(origin_head->ds_object, 3278 f, tx); 3279 origin_head->ds_feature_inuse[f] = B_TRUE; 3280 } 3281 if (origin_head_inuse) { 3282 dsl_dataset_activate_feature(clone->ds_object, f, tx); 3283 clone->ds_feature_inuse[f] = B_TRUE; 3284 } 3285 } 3286 3287 dmu_buf_will_dirty(clone->ds_dbuf, tx); 3288 dmu_buf_will_dirty(origin_head->ds_dbuf, tx); 3289 3290 if (clone->ds_objset != NULL) { 3291 dmu_objset_evict(clone->ds_objset); 3292 clone->ds_objset = NULL; 3293 } 3294 3295 if (origin_head->ds_objset != NULL) { 3296 dmu_objset_evict(origin_head->ds_objset); 3297 origin_head->ds_objset = NULL; 3298 } 3299 3300 unused_refres_delta = 3301 (int64_t)MIN(origin_head->ds_reserved, 3302 dsl_dataset_phys(origin_head)->ds_unique_bytes) - 3303 (int64_t)MIN(origin_head->ds_reserved, 3304 dsl_dataset_phys(clone)->ds_unique_bytes); 3305 3306 /* 3307 * Reset origin's unique bytes, if it exists. 3308 */ 3309 if (clone->ds_prev) { 3310 dsl_dataset_t *origin = clone->ds_prev; 3311 uint64_t comp, uncomp; 3312 3313 dmu_buf_will_dirty(origin->ds_dbuf, tx); 3314 dsl_deadlist_space_range(&clone->ds_deadlist, 3315 dsl_dataset_phys(origin)->ds_prev_snap_txg, UINT64_MAX, 3316 &dsl_dataset_phys(origin)->ds_unique_bytes, &comp, &uncomp); 3317 } 3318 3319 /* swap blkptrs */ 3320 { 3321 rrw_enter(&clone->ds_bp_rwlock, RW_WRITER, FTAG); 3322 rrw_enter(&origin_head->ds_bp_rwlock, RW_WRITER, FTAG); 3323 blkptr_t tmp; 3324 tmp = dsl_dataset_phys(origin_head)->ds_bp; 3325 dsl_dataset_phys(origin_head)->ds_bp = 3326 dsl_dataset_phys(clone)->ds_bp; 3327 dsl_dataset_phys(clone)->ds_bp = tmp; 3328 rrw_exit(&origin_head->ds_bp_rwlock, FTAG); 3329 rrw_exit(&clone->ds_bp_rwlock, FTAG); 3330 } 3331 3332 /* set dd_*_bytes */ 3333 { 3334 int64_t dused, dcomp, duncomp; 3335 uint64_t cdl_used, cdl_comp, cdl_uncomp; 3336 uint64_t odl_used, odl_comp, odl_uncomp; 3337 3338 ASSERT3U(dsl_dir_phys(clone->ds_dir)-> 3339 dd_used_breakdown[DD_USED_SNAP], ==, 0); 3340 3341 dsl_deadlist_space(&clone->ds_deadlist, 3342 &cdl_used, &cdl_comp, &cdl_uncomp); 3343 dsl_deadlist_space(&origin_head->ds_deadlist, 3344 &odl_used, &odl_comp, &odl_uncomp); 3345 3346 dused = dsl_dataset_phys(clone)->ds_referenced_bytes + 3347 cdl_used - 3348 (dsl_dataset_phys(origin_head)->ds_referenced_bytes + 3349 odl_used); 3350 dcomp = dsl_dataset_phys(clone)->ds_compressed_bytes + 3351 cdl_comp - 3352 (dsl_dataset_phys(origin_head)->ds_compressed_bytes + 3353 odl_comp); 3354 duncomp = dsl_dataset_phys(clone)->ds_uncompressed_bytes + 3355 cdl_uncomp - 3356 (dsl_dataset_phys(origin_head)->ds_uncompressed_bytes + 3357 odl_uncomp); 3358 3359 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD, 3360 dused, dcomp, duncomp, tx); 3361 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD, 3362 -dused, -dcomp, -duncomp, tx); 3363 3364 /* 3365 * The difference in the space used by snapshots is the 3366 * difference in snapshot space due to the head's 3367 * deadlist (since that's the only thing that's 3368 * changing that affects the snapused). 3369 */ 3370 dsl_deadlist_space_range(&clone->ds_deadlist, 3371 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3372 &cdl_used, &cdl_comp, &cdl_uncomp); 3373 dsl_deadlist_space_range(&origin_head->ds_deadlist, 3374 origin_head->ds_dir->dd_origin_txg, UINT64_MAX, 3375 &odl_used, &odl_comp, &odl_uncomp); 3376 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used, 3377 DD_USED_HEAD, DD_USED_SNAP, tx); 3378 } 3379 3380 /* swap ds_*_bytes */ 3381 SWITCH64(dsl_dataset_phys(origin_head)->ds_referenced_bytes, 3382 dsl_dataset_phys(clone)->ds_referenced_bytes); 3383 SWITCH64(dsl_dataset_phys(origin_head)->ds_compressed_bytes, 3384 dsl_dataset_phys(clone)->ds_compressed_bytes); 3385 SWITCH64(dsl_dataset_phys(origin_head)->ds_uncompressed_bytes, 3386 dsl_dataset_phys(clone)->ds_uncompressed_bytes); 3387 SWITCH64(dsl_dataset_phys(origin_head)->ds_unique_bytes, 3388 dsl_dataset_phys(clone)->ds_unique_bytes); 3389 3390 /* apply any parent delta for change in unconsumed refreservation */ 3391 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV, 3392 unused_refres_delta, 0, 0, tx); 3393 3394 /* 3395 * Swap deadlists. 3396 */ 3397 dsl_deadlist_close(&clone->ds_deadlist); 3398 dsl_deadlist_close(&origin_head->ds_deadlist); 3399 SWITCH64(dsl_dataset_phys(origin_head)->ds_deadlist_obj, 3400 dsl_dataset_phys(clone)->ds_deadlist_obj); 3401 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset, 3402 dsl_dataset_phys(clone)->ds_deadlist_obj); 3403 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset, 3404 dsl_dataset_phys(origin_head)->ds_deadlist_obj); 3405 3406 dsl_scan_ds_clone_swapped(origin_head, clone, tx); 3407 3408 spa_history_log_internal_ds(clone, "clone swap", tx, 3409 "parent=%s", origin_head->ds_dir->dd_myname); 3410 } 3411 3412 /* 3413 * Given a pool name and a dataset object number in that pool, 3414 * return the name of that dataset. 3415 */ 3416 int 3417 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 3418 { 3419 dsl_pool_t *dp; 3420 dsl_dataset_t *ds; 3421 int error; 3422 3423 error = dsl_pool_hold(pname, FTAG, &dp); 3424 if (error != 0) 3425 return (error); 3426 3427 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 3428 if (error == 0) { 3429 dsl_dataset_name(ds, buf); 3430 dsl_dataset_rele(ds, FTAG); 3431 } 3432 dsl_pool_rele(dp, FTAG); 3433 3434 return (error); 3435 } 3436 3437 int 3438 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 3439 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 3440 { 3441 int error = 0; 3442 3443 ASSERT3S(asize, >, 0); 3444 3445 /* 3446 * *ref_rsrv is the portion of asize that will come from any 3447 * unconsumed refreservation space. 3448 */ 3449 *ref_rsrv = 0; 3450 3451 mutex_enter(&ds->ds_lock); 3452 /* 3453 * Make a space adjustment for reserved bytes. 3454 */ 3455 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) { 3456 ASSERT3U(*used, >=, 3457 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3458 *used -= 3459 (ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes); 3460 *ref_rsrv = 3461 asize - MIN(asize, parent_delta(ds, asize + inflight)); 3462 } 3463 3464 if (!check_quota || ds->ds_quota == 0) { 3465 mutex_exit(&ds->ds_lock); 3466 return (0); 3467 } 3468 /* 3469 * If they are requesting more space, and our current estimate 3470 * is over quota, they get to try again unless the actual 3471 * on-disk is over quota and there are no pending changes (which 3472 * may free up space for us). 3473 */ 3474 if (dsl_dataset_phys(ds)->ds_referenced_bytes + inflight >= 3475 ds->ds_quota) { 3476 if (inflight > 0 || 3477 dsl_dataset_phys(ds)->ds_referenced_bytes < ds->ds_quota) 3478 error = SET_ERROR(ERESTART); 3479 else 3480 error = SET_ERROR(EDQUOT); 3481 } 3482 mutex_exit(&ds->ds_lock); 3483 3484 return (error); 3485 } 3486 3487 typedef struct dsl_dataset_set_qr_arg { 3488 const char *ddsqra_name; 3489 zprop_source_t ddsqra_source; 3490 uint64_t ddsqra_value; 3491 } dsl_dataset_set_qr_arg_t; 3492 3493 3494 /* ARGSUSED */ 3495 static int 3496 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx) 3497 { 3498 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3499 dsl_pool_t *dp = dmu_tx_pool(tx); 3500 dsl_dataset_t *ds; 3501 int error; 3502 uint64_t newval; 3503 3504 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA) 3505 return (SET_ERROR(ENOTSUP)); 3506 3507 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3508 if (error != 0) 3509 return (error); 3510 3511 if (ds->ds_is_snapshot) { 3512 dsl_dataset_rele(ds, FTAG); 3513 return (SET_ERROR(EINVAL)); 3514 } 3515 3516 error = dsl_prop_predict(ds->ds_dir, 3517 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3518 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3519 if (error != 0) { 3520 dsl_dataset_rele(ds, FTAG); 3521 return (error); 3522 } 3523 3524 if (newval == 0) { 3525 dsl_dataset_rele(ds, FTAG); 3526 return (0); 3527 } 3528 3529 if (newval < dsl_dataset_phys(ds)->ds_referenced_bytes || 3530 newval < ds->ds_reserved) { 3531 dsl_dataset_rele(ds, FTAG); 3532 return (SET_ERROR(ENOSPC)); 3533 } 3534 3535 dsl_dataset_rele(ds, FTAG); 3536 return (0); 3537 } 3538 3539 static void 3540 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx) 3541 { 3542 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3543 dsl_pool_t *dp = dmu_tx_pool(tx); 3544 dsl_dataset_t *ds; 3545 uint64_t newval; 3546 3547 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3548 3549 dsl_prop_set_sync_impl(ds, 3550 zfs_prop_to_name(ZFS_PROP_REFQUOTA), 3551 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1, 3552 &ddsqra->ddsqra_value, tx); 3553 3554 VERIFY0(dsl_prop_get_int_ds(ds, 3555 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval)); 3556 3557 if (ds->ds_quota != newval) { 3558 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3559 ds->ds_quota = newval; 3560 } 3561 dsl_dataset_rele(ds, FTAG); 3562 } 3563 3564 int 3565 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source, 3566 uint64_t refquota) 3567 { 3568 dsl_dataset_set_qr_arg_t ddsqra; 3569 3570 ddsqra.ddsqra_name = dsname; 3571 ddsqra.ddsqra_source = source; 3572 ddsqra.ddsqra_value = refquota; 3573 3574 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check, 3575 dsl_dataset_set_refquota_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE)); 3576 } 3577 3578 static int 3579 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx) 3580 { 3581 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3582 dsl_pool_t *dp = dmu_tx_pool(tx); 3583 dsl_dataset_t *ds; 3584 int error; 3585 uint64_t newval, unique; 3586 3587 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION) 3588 return (SET_ERROR(ENOTSUP)); 3589 3590 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds); 3591 if (error != 0) 3592 return (error); 3593 3594 if (ds->ds_is_snapshot) { 3595 dsl_dataset_rele(ds, FTAG); 3596 return (SET_ERROR(EINVAL)); 3597 } 3598 3599 error = dsl_prop_predict(ds->ds_dir, 3600 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3601 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval); 3602 if (error != 0) { 3603 dsl_dataset_rele(ds, FTAG); 3604 return (error); 3605 } 3606 3607 /* 3608 * If we are doing the preliminary check in open context, the 3609 * space estimates may be inaccurate. 3610 */ 3611 if (!dmu_tx_is_syncing(tx)) { 3612 dsl_dataset_rele(ds, FTAG); 3613 return (0); 3614 } 3615 3616 mutex_enter(&ds->ds_lock); 3617 if (!DS_UNIQUE_IS_ACCURATE(ds)) 3618 dsl_dataset_recalc_head_uniq(ds); 3619 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3620 mutex_exit(&ds->ds_lock); 3621 3622 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) { 3623 uint64_t delta = MAX(unique, newval) - 3624 MAX(unique, ds->ds_reserved); 3625 3626 if (delta > 3627 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) || 3628 (ds->ds_quota > 0 && newval > ds->ds_quota)) { 3629 dsl_dataset_rele(ds, FTAG); 3630 return (SET_ERROR(ENOSPC)); 3631 } 3632 } 3633 3634 dsl_dataset_rele(ds, FTAG); 3635 return (0); 3636 } 3637 3638 void 3639 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds, 3640 zprop_source_t source, uint64_t value, dmu_tx_t *tx) 3641 { 3642 uint64_t newval; 3643 uint64_t unique; 3644 int64_t delta; 3645 3646 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 3647 source, sizeof (value), 1, &value, tx); 3648 3649 VERIFY0(dsl_prop_get_int_ds(ds, 3650 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval)); 3651 3652 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3653 mutex_enter(&ds->ds_dir->dd_lock); 3654 mutex_enter(&ds->ds_lock); 3655 ASSERT(DS_UNIQUE_IS_ACCURATE(ds)); 3656 unique = dsl_dataset_phys(ds)->ds_unique_bytes; 3657 delta = MAX(0, (int64_t)(newval - unique)) - 3658 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3659 ds->ds_reserved = newval; 3660 mutex_exit(&ds->ds_lock); 3661 3662 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3663 mutex_exit(&ds->ds_dir->dd_lock); 3664 } 3665 3666 static void 3667 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx) 3668 { 3669 dsl_dataset_set_qr_arg_t *ddsqra = arg; 3670 dsl_pool_t *dp = dmu_tx_pool(tx); 3671 dsl_dataset_t *ds; 3672 3673 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds)); 3674 dsl_dataset_set_refreservation_sync_impl(ds, 3675 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx); 3676 dsl_dataset_rele(ds, FTAG); 3677 } 3678 3679 int 3680 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source, 3681 uint64_t refreservation) 3682 { 3683 dsl_dataset_set_qr_arg_t ddsqra; 3684 3685 ddsqra.ddsqra_name = dsname; 3686 ddsqra.ddsqra_source = source; 3687 ddsqra.ddsqra_value = refreservation; 3688 3689 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check, 3690 dsl_dataset_set_refreservation_sync, &ddsqra, 3691 0, ZFS_SPACE_CHECK_NONE)); 3692 } 3693 3694 /* 3695 * Return (in *usedp) the amount of space written in new that is not 3696 * present in oldsnap. New may be a snapshot or the head. Old must be 3697 * a snapshot before new, in new's filesystem (or its origin). If not then 3698 * fail and return EINVAL. 3699 * 3700 * The written space is calculated by considering two components: First, we 3701 * ignore any freed space, and calculate the written as new's used space 3702 * minus old's used space. Next, we add in the amount of space that was freed 3703 * between the two snapshots, thus reducing new's used space relative to old's. 3704 * Specifically, this is the space that was born before old->ds_creation_txg, 3705 * and freed before new (ie. on new's deadlist or a previous deadlist). 3706 * 3707 * space freed [---------------------] 3708 * snapshots ---O-------O--------O-------O------ 3709 * oldsnap new 3710 */ 3711 int 3712 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new, 3713 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3714 { 3715 int err = 0; 3716 uint64_t snapobj; 3717 dsl_pool_t *dp = new->ds_dir->dd_pool; 3718 3719 ASSERT(dsl_pool_config_held(dp)); 3720 3721 *usedp = 0; 3722 *usedp += dsl_dataset_phys(new)->ds_referenced_bytes; 3723 *usedp -= dsl_dataset_phys(oldsnap)->ds_referenced_bytes; 3724 3725 *compp = 0; 3726 *compp += dsl_dataset_phys(new)->ds_compressed_bytes; 3727 *compp -= dsl_dataset_phys(oldsnap)->ds_compressed_bytes; 3728 3729 *uncompp = 0; 3730 *uncompp += dsl_dataset_phys(new)->ds_uncompressed_bytes; 3731 *uncompp -= dsl_dataset_phys(oldsnap)->ds_uncompressed_bytes; 3732 3733 snapobj = new->ds_object; 3734 while (snapobj != oldsnap->ds_object) { 3735 dsl_dataset_t *snap; 3736 uint64_t used, comp, uncomp; 3737 3738 if (snapobj == new->ds_object) { 3739 snap = new; 3740 } else { 3741 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap); 3742 if (err != 0) 3743 break; 3744 } 3745 3746 if (dsl_dataset_phys(snap)->ds_prev_snap_txg == 3747 dsl_dataset_phys(oldsnap)->ds_creation_txg) { 3748 /* 3749 * The blocks in the deadlist can not be born after 3750 * ds_prev_snap_txg, so get the whole deadlist space, 3751 * which is more efficient (especially for old-format 3752 * deadlists). Unfortunately the deadlist code 3753 * doesn't have enough information to make this 3754 * optimization itself. 3755 */ 3756 dsl_deadlist_space(&snap->ds_deadlist, 3757 &used, &comp, &uncomp); 3758 } else { 3759 dsl_deadlist_space_range(&snap->ds_deadlist, 3760 0, dsl_dataset_phys(oldsnap)->ds_creation_txg, 3761 &used, &comp, &uncomp); 3762 } 3763 *usedp += used; 3764 *compp += comp; 3765 *uncompp += uncomp; 3766 3767 /* 3768 * If we get to the beginning of the chain of snapshots 3769 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap 3770 * was not a snapshot of/before new. 3771 */ 3772 snapobj = dsl_dataset_phys(snap)->ds_prev_snap_obj; 3773 if (snap != new) 3774 dsl_dataset_rele(snap, FTAG); 3775 if (snapobj == 0) { 3776 err = SET_ERROR(EINVAL); 3777 break; 3778 } 3779 3780 } 3781 return (err); 3782 } 3783 3784 /* 3785 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap, 3786 * lastsnap, and all snapshots in between are deleted. 3787 * 3788 * blocks that would be freed [---------------------------] 3789 * snapshots ---O-------O--------O-------O--------O 3790 * firstsnap lastsnap 3791 * 3792 * This is the set of blocks that were born after the snap before firstsnap, 3793 * (birth > firstsnap->prev_snap_txg) and died before the snap after the 3794 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist). 3795 * We calculate this by iterating over the relevant deadlists (from the snap 3796 * after lastsnap, backward to the snap after firstsnap), summing up the 3797 * space on the deadlist that was born after the snap before firstsnap. 3798 */ 3799 int 3800 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, 3801 dsl_dataset_t *lastsnap, 3802 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp) 3803 { 3804 int err = 0; 3805 uint64_t snapobj; 3806 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool; 3807 3808 ASSERT(firstsnap->ds_is_snapshot); 3809 ASSERT(lastsnap->ds_is_snapshot); 3810 3811 /* 3812 * Check that the snapshots are in the same dsl_dir, and firstsnap 3813 * is before lastsnap. 3814 */ 3815 if (firstsnap->ds_dir != lastsnap->ds_dir || 3816 dsl_dataset_phys(firstsnap)->ds_creation_txg > 3817 dsl_dataset_phys(lastsnap)->ds_creation_txg) 3818 return (SET_ERROR(EINVAL)); 3819 3820 *usedp = *compp = *uncompp = 0; 3821 3822 snapobj = dsl_dataset_phys(lastsnap)->ds_next_snap_obj; 3823 while (snapobj != firstsnap->ds_object) { 3824 dsl_dataset_t *ds; 3825 uint64_t used, comp, uncomp; 3826 3827 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds); 3828 if (err != 0) 3829 break; 3830 3831 dsl_deadlist_space_range(&ds->ds_deadlist, 3832 dsl_dataset_phys(firstsnap)->ds_prev_snap_txg, UINT64_MAX, 3833 &used, &comp, &uncomp); 3834 *usedp += used; 3835 *compp += comp; 3836 *uncompp += uncomp; 3837 3838 snapobj = dsl_dataset_phys(ds)->ds_prev_snap_obj; 3839 ASSERT3U(snapobj, !=, 0); 3840 dsl_dataset_rele(ds, FTAG); 3841 } 3842 return (err); 3843 } 3844 3845 /* 3846 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline. 3847 * For example, they could both be snapshots of the same filesystem, and 3848 * 'earlier' is before 'later'. Or 'earlier' could be the origin of 3849 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's 3850 * filesystem. Or 'earlier' could be the origin's origin. 3851 * 3852 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg. 3853 */ 3854 boolean_t 3855 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier, 3856 uint64_t earlier_txg) 3857 { 3858 dsl_pool_t *dp = later->ds_dir->dd_pool; 3859 int error; 3860 boolean_t ret; 3861 3862 ASSERT(dsl_pool_config_held(dp)); 3863 ASSERT(earlier->ds_is_snapshot || earlier_txg != 0); 3864 3865 if (earlier_txg == 0) 3866 earlier_txg = dsl_dataset_phys(earlier)->ds_creation_txg; 3867 3868 if (later->ds_is_snapshot && 3869 earlier_txg >= dsl_dataset_phys(later)->ds_creation_txg) 3870 return (B_FALSE); 3871 3872 if (later->ds_dir == earlier->ds_dir) 3873 return (B_TRUE); 3874 if (!dsl_dir_is_clone(later->ds_dir)) 3875 return (B_FALSE); 3876 3877 if (dsl_dir_phys(later->ds_dir)->dd_origin_obj == earlier->ds_object) 3878 return (B_TRUE); 3879 dsl_dataset_t *origin; 3880 error = dsl_dataset_hold_obj(dp, 3881 dsl_dir_phys(later->ds_dir)->dd_origin_obj, FTAG, &origin); 3882 if (error != 0) 3883 return (B_FALSE); 3884 ret = dsl_dataset_is_before(origin, earlier, earlier_txg); 3885 dsl_dataset_rele(origin, FTAG); 3886 return (ret); 3887 } 3888 3889 void 3890 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx) 3891 { 3892 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 3893 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx); 3894 } 3895 3896 boolean_t 3897 dsl_dataset_is_zapified(dsl_dataset_t *ds) 3898 { 3899 dmu_object_info_t doi; 3900 3901 dmu_object_info_from_db(ds->ds_dbuf, &doi); 3902 return (doi.doi_type == DMU_OTN_ZAP_METADATA); 3903 } 3904 3905 boolean_t 3906 dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds) 3907 { 3908 return (dsl_dataset_is_zapified(ds) && 3909 zap_contains(ds->ds_dir->dd_pool->dp_meta_objset, 3910 ds->ds_object, DS_FIELD_RESUME_TOGUID) == 0); 3911 } 3912