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