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