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 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/dmu_objset.h> 27 #include <sys/dsl_dataset.h> 28 #include <sys/dsl_dir.h> 29 #include <sys/dsl_prop.h> 30 #include <sys/dsl_synctask.h> 31 #include <sys/dmu_traverse.h> 32 #include <sys/dmu_tx.h> 33 #include <sys/arc.h> 34 #include <sys/zio.h> 35 #include <sys/zap.h> 36 #include <sys/unique.h> 37 #include <sys/zfs_context.h> 38 #include <sys/zfs_ioctl.h> 39 #include <sys/spa.h> 40 #include <sys/zfs_znode.h> 41 #include <sys/sunddi.h> 42 43 static char *dsl_reaper = "the grim reaper"; 44 45 static dsl_checkfunc_t dsl_dataset_destroy_begin_check; 46 static dsl_syncfunc_t dsl_dataset_destroy_begin_sync; 47 static dsl_checkfunc_t dsl_dataset_rollback_check; 48 static dsl_syncfunc_t dsl_dataset_rollback_sync; 49 static dsl_syncfunc_t dsl_dataset_set_reservation_sync; 50 51 #define DS_REF_MAX (1ULL << 62) 52 53 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 54 55 #define DSL_DATASET_IS_DESTROYED(ds) ((ds)->ds_owner == dsl_reaper) 56 57 58 /* 59 * Figure out how much of this delta should be propogated to the dsl_dir 60 * layer. If there's a refreservation, that space has already been 61 * partially accounted for in our ancestors. 62 */ 63 static int64_t 64 parent_delta(dsl_dataset_t *ds, int64_t delta) 65 { 66 uint64_t old_bytes, new_bytes; 67 68 if (ds->ds_reserved == 0) 69 return (delta); 70 71 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 72 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 73 74 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 75 return (new_bytes - old_bytes); 76 } 77 78 void 79 dsl_dataset_block_born(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 80 { 81 int used = bp_get_dasize(tx->tx_pool->dp_spa, bp); 82 int compressed = BP_GET_PSIZE(bp); 83 int uncompressed = BP_GET_UCSIZE(bp); 84 int64_t delta; 85 86 dprintf_bp(bp, "born, ds=%p\n", ds); 87 88 ASSERT(dmu_tx_is_syncing(tx)); 89 /* It could have been compressed away to nothing */ 90 if (BP_IS_HOLE(bp)) 91 return; 92 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 93 ASSERT3U(BP_GET_TYPE(bp), <, DMU_OT_NUMTYPES); 94 if (ds == NULL) { 95 /* 96 * Account for the meta-objset space in its placeholder 97 * dsl_dir. 98 */ 99 ASSERT3U(compressed, ==, uncompressed); /* it's all metadata */ 100 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, DD_USED_HEAD, 101 used, compressed, uncompressed, tx); 102 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx); 103 return; 104 } 105 dmu_buf_will_dirty(ds->ds_dbuf, tx); 106 mutex_enter(&ds->ds_dir->dd_lock); 107 mutex_enter(&ds->ds_lock); 108 delta = parent_delta(ds, used); 109 ds->ds_phys->ds_used_bytes += used; 110 ds->ds_phys->ds_compressed_bytes += compressed; 111 ds->ds_phys->ds_uncompressed_bytes += uncompressed; 112 ds->ds_phys->ds_unique_bytes += used; 113 mutex_exit(&ds->ds_lock); 114 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 115 compressed, uncompressed, tx); 116 dsl_dir_transfer_space(ds->ds_dir, used - delta, 117 DD_USED_REFRSRV, DD_USED_HEAD, tx); 118 mutex_exit(&ds->ds_dir->dd_lock); 119 } 120 121 int 122 dsl_dataset_block_kill(dsl_dataset_t *ds, blkptr_t *bp, zio_t *pio, 123 dmu_tx_t *tx) 124 { 125 int used = bp_get_dasize(tx->tx_pool->dp_spa, bp); 126 int compressed = BP_GET_PSIZE(bp); 127 int uncompressed = BP_GET_UCSIZE(bp); 128 129 ASSERT(pio != NULL); 130 ASSERT(dmu_tx_is_syncing(tx)); 131 /* No block pointer => nothing to free */ 132 if (BP_IS_HOLE(bp)) 133 return (0); 134 135 ASSERT(used > 0); 136 if (ds == NULL) { 137 int err; 138 /* 139 * Account for the meta-objset space in its placeholder 140 * dataset. 141 */ 142 err = dsl_free(pio, tx->tx_pool, 143 tx->tx_txg, bp, NULL, NULL, ARC_NOWAIT); 144 ASSERT(err == 0); 145 146 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, DD_USED_HEAD, 147 -used, -compressed, -uncompressed, tx); 148 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx); 149 return (used); 150 } 151 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 152 153 ASSERT(!dsl_dataset_is_snapshot(ds)); 154 dmu_buf_will_dirty(ds->ds_dbuf, tx); 155 156 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) { 157 int err; 158 int64_t delta; 159 160 dprintf_bp(bp, "freeing: %s", ""); 161 err = dsl_free(pio, tx->tx_pool, 162 tx->tx_txg, bp, NULL, NULL, ARC_NOWAIT); 163 ASSERT(err == 0); 164 165 mutex_enter(&ds->ds_dir->dd_lock); 166 mutex_enter(&ds->ds_lock); 167 ASSERT(ds->ds_phys->ds_unique_bytes >= used || 168 !DS_UNIQUE_IS_ACCURATE(ds)); 169 delta = parent_delta(ds, -used); 170 ds->ds_phys->ds_unique_bytes -= used; 171 mutex_exit(&ds->ds_lock); 172 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 173 delta, -compressed, -uncompressed, tx); 174 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 175 DD_USED_REFRSRV, DD_USED_HEAD, tx); 176 mutex_exit(&ds->ds_dir->dd_lock); 177 } else { 178 dprintf_bp(bp, "putting on dead list: %s", ""); 179 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, bp, tx)); 180 ASSERT3U(ds->ds_prev->ds_object, ==, 181 ds->ds_phys->ds_prev_snap_obj); 182 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0); 183 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 184 if (ds->ds_prev->ds_phys->ds_next_snap_obj == 185 ds->ds_object && bp->blk_birth > 186 ds->ds_prev->ds_phys->ds_prev_snap_txg) { 187 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 188 mutex_enter(&ds->ds_prev->ds_lock); 189 ds->ds_prev->ds_phys->ds_unique_bytes += used; 190 mutex_exit(&ds->ds_prev->ds_lock); 191 } 192 if (bp->blk_birth > ds->ds_origin_txg) { 193 dsl_dir_transfer_space(ds->ds_dir, used, 194 DD_USED_HEAD, DD_USED_SNAP, tx); 195 } 196 } 197 mutex_enter(&ds->ds_lock); 198 ASSERT3U(ds->ds_phys->ds_used_bytes, >=, used); 199 ds->ds_phys->ds_used_bytes -= used; 200 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed); 201 ds->ds_phys->ds_compressed_bytes -= compressed; 202 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed); 203 ds->ds_phys->ds_uncompressed_bytes -= uncompressed; 204 mutex_exit(&ds->ds_lock); 205 206 return (used); 207 } 208 209 uint64_t 210 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 211 { 212 uint64_t trysnap = 0; 213 214 if (ds == NULL) 215 return (0); 216 /* 217 * The snapshot creation could fail, but that would cause an 218 * incorrect FALSE return, which would only result in an 219 * overestimation of the amount of space that an operation would 220 * consume, which is OK. 221 * 222 * There's also a small window where we could miss a pending 223 * snapshot, because we could set the sync task in the quiescing 224 * phase. So this should only be used as a guess. 225 */ 226 if (ds->ds_trysnap_txg > 227 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 228 trysnap = ds->ds_trysnap_txg; 229 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap)); 230 } 231 232 int 233 dsl_dataset_block_freeable(dsl_dataset_t *ds, uint64_t blk_birth) 234 { 235 return (blk_birth > dsl_dataset_prev_snap_txg(ds)); 236 } 237 238 /* ARGSUSED */ 239 static void 240 dsl_dataset_evict(dmu_buf_t *db, void *dsv) 241 { 242 dsl_dataset_t *ds = dsv; 243 244 ASSERT(ds->ds_owner == NULL || DSL_DATASET_IS_DESTROYED(ds)); 245 246 dprintf_ds(ds, "evicting %s\n", ""); 247 248 unique_remove(ds->ds_fsid_guid); 249 250 if (ds->ds_user_ptr != NULL) 251 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 252 253 if (ds->ds_prev) { 254 dsl_dataset_drop_ref(ds->ds_prev, ds); 255 ds->ds_prev = NULL; 256 } 257 258 bplist_close(&ds->ds_deadlist); 259 if (ds->ds_dir) 260 dsl_dir_close(ds->ds_dir, ds); 261 262 ASSERT(!list_link_active(&ds->ds_synced_link)); 263 264 mutex_destroy(&ds->ds_lock); 265 mutex_destroy(&ds->ds_opening_lock); 266 mutex_destroy(&ds->ds_deadlist.bpl_lock); 267 rw_destroy(&ds->ds_rwlock); 268 cv_destroy(&ds->ds_exclusive_cv); 269 270 kmem_free(ds, sizeof (dsl_dataset_t)); 271 } 272 273 static int 274 dsl_dataset_get_snapname(dsl_dataset_t *ds) 275 { 276 dsl_dataset_phys_t *headphys; 277 int err; 278 dmu_buf_t *headdbuf; 279 dsl_pool_t *dp = ds->ds_dir->dd_pool; 280 objset_t *mos = dp->dp_meta_objset; 281 282 if (ds->ds_snapname[0]) 283 return (0); 284 if (ds->ds_phys->ds_next_snap_obj == 0) 285 return (0); 286 287 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 288 FTAG, &headdbuf); 289 if (err) 290 return (err); 291 headphys = headdbuf->db_data; 292 err = zap_value_search(dp->dp_meta_objset, 293 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 294 dmu_buf_rele(headdbuf, FTAG); 295 return (err); 296 } 297 298 static int 299 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 300 { 301 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 302 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 303 matchtype_t mt; 304 int err; 305 306 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 307 mt = MT_FIRST; 308 else 309 mt = MT_EXACT; 310 311 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 312 value, mt, NULL, 0, NULL); 313 if (err == ENOTSUP && mt == MT_FIRST) 314 err = zap_lookup(mos, snapobj, name, 8, 1, value); 315 return (err); 316 } 317 318 static int 319 dsl_dataset_snap_remove(dsl_dataset_t *ds, char *name, dmu_tx_t *tx) 320 { 321 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 322 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 323 matchtype_t mt; 324 int err; 325 326 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 327 mt = MT_FIRST; 328 else 329 mt = MT_EXACT; 330 331 err = zap_remove_norm(mos, snapobj, name, mt, tx); 332 if (err == ENOTSUP && mt == MT_FIRST) 333 err = zap_remove(mos, snapobj, name, tx); 334 return (err); 335 } 336 337 static int 338 dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag, 339 dsl_dataset_t **dsp) 340 { 341 objset_t *mos = dp->dp_meta_objset; 342 dmu_buf_t *dbuf; 343 dsl_dataset_t *ds; 344 int err; 345 346 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 347 dsl_pool_sync_context(dp)); 348 349 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 350 if (err) 351 return (err); 352 ds = dmu_buf_get_user(dbuf); 353 if (ds == NULL) { 354 dsl_dataset_t *winner; 355 356 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 357 ds->ds_dbuf = dbuf; 358 ds->ds_object = dsobj; 359 ds->ds_phys = dbuf->db_data; 360 361 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 362 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 363 mutex_init(&ds->ds_deadlist.bpl_lock, NULL, MUTEX_DEFAULT, 364 NULL); 365 rw_init(&ds->ds_rwlock, 0, 0, 0); 366 cv_init(&ds->ds_exclusive_cv, NULL, CV_DEFAULT, NULL); 367 368 err = bplist_open(&ds->ds_deadlist, 369 mos, ds->ds_phys->ds_deadlist_obj); 370 if (err == 0) { 371 err = dsl_dir_open_obj(dp, 372 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 373 } 374 if (err) { 375 /* 376 * we don't really need to close the blist if we 377 * just opened it. 378 */ 379 mutex_destroy(&ds->ds_lock); 380 mutex_destroy(&ds->ds_opening_lock); 381 mutex_destroy(&ds->ds_deadlist.bpl_lock); 382 rw_destroy(&ds->ds_rwlock); 383 cv_destroy(&ds->ds_exclusive_cv); 384 kmem_free(ds, sizeof (dsl_dataset_t)); 385 dmu_buf_rele(dbuf, tag); 386 return (err); 387 } 388 389 if (!dsl_dataset_is_snapshot(ds)) { 390 ds->ds_snapname[0] = '\0'; 391 if (ds->ds_phys->ds_prev_snap_obj) { 392 err = dsl_dataset_get_ref(dp, 393 ds->ds_phys->ds_prev_snap_obj, 394 ds, &ds->ds_prev); 395 } 396 397 if (err == 0 && dsl_dir_is_clone(ds->ds_dir)) { 398 dsl_dataset_t *origin; 399 400 err = dsl_dataset_hold_obj(dp, 401 ds->ds_dir->dd_phys->dd_origin_obj, 402 FTAG, &origin); 403 if (err == 0) { 404 ds->ds_origin_txg = 405 origin->ds_phys->ds_creation_txg; 406 dsl_dataset_rele(origin, FTAG); 407 } 408 } 409 } else if (zfs_flags & ZFS_DEBUG_SNAPNAMES) { 410 err = dsl_dataset_get_snapname(ds); 411 } 412 413 if (err == 0 && !dsl_dataset_is_snapshot(ds)) { 414 /* 415 * In sync context, we're called with either no lock 416 * or with the write lock. If we're not syncing, 417 * we're always called with the read lock held. 418 */ 419 boolean_t need_lock = 420 !RW_WRITE_HELD(&dp->dp_config_rwlock) && 421 dsl_pool_sync_context(dp); 422 423 if (need_lock) 424 rw_enter(&dp->dp_config_rwlock, RW_READER); 425 426 err = dsl_prop_get_ds(ds, 427 "refreservation", sizeof (uint64_t), 1, 428 &ds->ds_reserved, NULL); 429 if (err == 0) { 430 err = dsl_prop_get_ds(ds, 431 "refquota", sizeof (uint64_t), 1, 432 &ds->ds_quota, NULL); 433 } 434 435 if (need_lock) 436 rw_exit(&dp->dp_config_rwlock); 437 } else { 438 ds->ds_reserved = ds->ds_quota = 0; 439 } 440 441 if (err == 0) { 442 winner = dmu_buf_set_user_ie(dbuf, ds, &ds->ds_phys, 443 dsl_dataset_evict); 444 } 445 if (err || winner) { 446 bplist_close(&ds->ds_deadlist); 447 if (ds->ds_prev) 448 dsl_dataset_drop_ref(ds->ds_prev, ds); 449 dsl_dir_close(ds->ds_dir, ds); 450 mutex_destroy(&ds->ds_lock); 451 mutex_destroy(&ds->ds_opening_lock); 452 mutex_destroy(&ds->ds_deadlist.bpl_lock); 453 rw_destroy(&ds->ds_rwlock); 454 cv_destroy(&ds->ds_exclusive_cv); 455 kmem_free(ds, sizeof (dsl_dataset_t)); 456 if (err) { 457 dmu_buf_rele(dbuf, tag); 458 return (err); 459 } 460 ds = winner; 461 } else { 462 ds->ds_fsid_guid = 463 unique_insert(ds->ds_phys->ds_fsid_guid); 464 } 465 } 466 ASSERT3P(ds->ds_dbuf, ==, dbuf); 467 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 468 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 || 469 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 470 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 471 mutex_enter(&ds->ds_lock); 472 if (!dsl_pool_sync_context(dp) && DSL_DATASET_IS_DESTROYED(ds)) { 473 mutex_exit(&ds->ds_lock); 474 dmu_buf_rele(ds->ds_dbuf, tag); 475 return (ENOENT); 476 } 477 mutex_exit(&ds->ds_lock); 478 *dsp = ds; 479 return (0); 480 } 481 482 static int 483 dsl_dataset_hold_ref(dsl_dataset_t *ds, void *tag) 484 { 485 dsl_pool_t *dp = ds->ds_dir->dd_pool; 486 487 /* 488 * In syncing context we don't want the rwlock lock: there 489 * may be an existing writer waiting for sync phase to 490 * finish. We don't need to worry about such writers, since 491 * sync phase is single-threaded, so the writer can't be 492 * doing anything while we are active. 493 */ 494 if (dsl_pool_sync_context(dp)) { 495 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 496 return (0); 497 } 498 499 /* 500 * Normal users will hold the ds_rwlock as a READER until they 501 * are finished (i.e., call dsl_dataset_rele()). "Owners" will 502 * drop their READER lock after they set the ds_owner field. 503 * 504 * If the dataset is being destroyed, the destroy thread will 505 * obtain a WRITER lock for exclusive access after it's done its 506 * open-context work and then change the ds_owner to 507 * dsl_reaper once destruction is assured. So threads 508 * may block here temporarily, until the "destructability" of 509 * the dataset is determined. 510 */ 511 ASSERT(!RW_WRITE_HELD(&dp->dp_config_rwlock)); 512 mutex_enter(&ds->ds_lock); 513 while (!rw_tryenter(&ds->ds_rwlock, RW_READER)) { 514 rw_exit(&dp->dp_config_rwlock); 515 cv_wait(&ds->ds_exclusive_cv, &ds->ds_lock); 516 if (DSL_DATASET_IS_DESTROYED(ds)) { 517 mutex_exit(&ds->ds_lock); 518 dsl_dataset_drop_ref(ds, tag); 519 rw_enter(&dp->dp_config_rwlock, RW_READER); 520 return (ENOENT); 521 } 522 rw_enter(&dp->dp_config_rwlock, RW_READER); 523 } 524 mutex_exit(&ds->ds_lock); 525 return (0); 526 } 527 528 int 529 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 530 dsl_dataset_t **dsp) 531 { 532 int err = dsl_dataset_get_ref(dp, dsobj, tag, dsp); 533 534 if (err) 535 return (err); 536 return (dsl_dataset_hold_ref(*dsp, tag)); 537 } 538 539 int 540 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, int flags, void *owner, 541 dsl_dataset_t **dsp) 542 { 543 int err = dsl_dataset_hold_obj(dp, dsobj, owner, dsp); 544 545 ASSERT(DS_MODE_TYPE(flags) != DS_MODE_USER); 546 547 if (err) 548 return (err); 549 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 550 dsl_dataset_rele(*dsp, owner); 551 return (EBUSY); 552 } 553 return (0); 554 } 555 556 int 557 dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp) 558 { 559 dsl_dir_t *dd; 560 dsl_pool_t *dp; 561 const char *snapname; 562 uint64_t obj; 563 int err = 0; 564 565 err = dsl_dir_open_spa(NULL, name, FTAG, &dd, &snapname); 566 if (err) 567 return (err); 568 569 dp = dd->dd_pool; 570 obj = dd->dd_phys->dd_head_dataset_obj; 571 rw_enter(&dp->dp_config_rwlock, RW_READER); 572 if (obj) 573 err = dsl_dataset_get_ref(dp, obj, tag, dsp); 574 else 575 err = ENOENT; 576 if (err) 577 goto out; 578 579 err = dsl_dataset_hold_ref(*dsp, tag); 580 581 /* we may be looking for a snapshot */ 582 if (err == 0 && snapname != NULL) { 583 dsl_dataset_t *ds = NULL; 584 585 if (*snapname++ != '@') { 586 dsl_dataset_rele(*dsp, tag); 587 err = ENOENT; 588 goto out; 589 } 590 591 dprintf("looking for snapshot '%s'\n", snapname); 592 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 593 if (err == 0) 594 err = dsl_dataset_get_ref(dp, obj, tag, &ds); 595 dsl_dataset_rele(*dsp, tag); 596 597 ASSERT3U((err == 0), ==, (ds != NULL)); 598 599 if (ds) { 600 mutex_enter(&ds->ds_lock); 601 if (ds->ds_snapname[0] == 0) 602 (void) strlcpy(ds->ds_snapname, snapname, 603 sizeof (ds->ds_snapname)); 604 mutex_exit(&ds->ds_lock); 605 err = dsl_dataset_hold_ref(ds, tag); 606 *dsp = err ? NULL : ds; 607 } 608 } 609 out: 610 rw_exit(&dp->dp_config_rwlock); 611 dsl_dir_close(dd, FTAG); 612 return (err); 613 } 614 615 int 616 dsl_dataset_own(const char *name, int flags, void *owner, dsl_dataset_t **dsp) 617 { 618 int err = dsl_dataset_hold(name, owner, dsp); 619 if (err) 620 return (err); 621 if ((*dsp)->ds_phys->ds_num_children > 0 && 622 !DS_MODE_IS_READONLY(flags)) { 623 dsl_dataset_rele(*dsp, owner); 624 return (EROFS); 625 } 626 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 627 dsl_dataset_rele(*dsp, owner); 628 return (EBUSY); 629 } 630 return (0); 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 VERIFY(0 == 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 static int 659 dsl_dataset_namelen(dsl_dataset_t *ds) 660 { 661 int result; 662 663 if (ds == NULL) { 664 result = 3; /* "mos" */ 665 } else { 666 result = dsl_dir_namelen(ds->ds_dir); 667 VERIFY(0 == dsl_dataset_get_snapname(ds)); 668 if (ds->ds_snapname[0]) { 669 ++result; /* adding one for the @-sign */ 670 if (!MUTEX_HELD(&ds->ds_lock)) { 671 mutex_enter(&ds->ds_lock); 672 result += strlen(ds->ds_snapname); 673 mutex_exit(&ds->ds_lock); 674 } else { 675 result += strlen(ds->ds_snapname); 676 } 677 } 678 } 679 680 return (result); 681 } 682 683 void 684 dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag) 685 { 686 dmu_buf_rele(ds->ds_dbuf, tag); 687 } 688 689 void 690 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 691 { 692 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) { 693 rw_exit(&ds->ds_rwlock); 694 } 695 dsl_dataset_drop_ref(ds, tag); 696 } 697 698 void 699 dsl_dataset_disown(dsl_dataset_t *ds, void *owner) 700 { 701 ASSERT((ds->ds_owner == owner && ds->ds_dbuf) || 702 (DSL_DATASET_IS_DESTROYED(ds) && ds->ds_dbuf == NULL)); 703 704 mutex_enter(&ds->ds_lock); 705 ds->ds_owner = NULL; 706 if (RW_WRITE_HELD(&ds->ds_rwlock)) { 707 rw_exit(&ds->ds_rwlock); 708 cv_broadcast(&ds->ds_exclusive_cv); 709 } 710 mutex_exit(&ds->ds_lock); 711 if (ds->ds_dbuf) 712 dsl_dataset_drop_ref(ds, owner); 713 else 714 dsl_dataset_evict(ds->ds_dbuf, ds); 715 } 716 717 boolean_t 718 dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok, void *owner) 719 { 720 boolean_t gotit = FALSE; 721 722 mutex_enter(&ds->ds_lock); 723 if (ds->ds_owner == NULL && 724 (!DS_IS_INCONSISTENT(ds) || inconsistentok)) { 725 ds->ds_owner = owner; 726 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) 727 rw_exit(&ds->ds_rwlock); 728 gotit = TRUE; 729 } 730 mutex_exit(&ds->ds_lock); 731 return (gotit); 732 } 733 734 void 735 dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *owner) 736 { 737 ASSERT3P(owner, ==, ds->ds_owner); 738 if (!RW_WRITE_HELD(&ds->ds_rwlock)) 739 rw_enter(&ds->ds_rwlock, RW_WRITER); 740 } 741 742 uint64_t 743 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 744 uint64_t flags, dmu_tx_t *tx) 745 { 746 dsl_pool_t *dp = dd->dd_pool; 747 dmu_buf_t *dbuf; 748 dsl_dataset_phys_t *dsphys; 749 uint64_t dsobj; 750 objset_t *mos = dp->dp_meta_objset; 751 752 if (origin == NULL) 753 origin = dp->dp_origin_snap; 754 755 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 756 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 757 ASSERT(dmu_tx_is_syncing(tx)); 758 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 759 760 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 761 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 762 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 763 dmu_buf_will_dirty(dbuf, tx); 764 dsphys = dbuf->db_data; 765 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 766 dsphys->ds_dir_obj = dd->dd_object; 767 dsphys->ds_flags = flags; 768 dsphys->ds_fsid_guid = unique_create(); 769 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 770 sizeof (dsphys->ds_guid)); 771 dsphys->ds_snapnames_zapobj = 772 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 773 DMU_OT_NONE, 0, tx); 774 dsphys->ds_creation_time = gethrestime_sec(); 775 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 776 dsphys->ds_deadlist_obj = 777 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 778 779 if (origin) { 780 dsphys->ds_prev_snap_obj = origin->ds_object; 781 dsphys->ds_prev_snap_txg = 782 origin->ds_phys->ds_creation_txg; 783 dsphys->ds_used_bytes = 784 origin->ds_phys->ds_used_bytes; 785 dsphys->ds_compressed_bytes = 786 origin->ds_phys->ds_compressed_bytes; 787 dsphys->ds_uncompressed_bytes = 788 origin->ds_phys->ds_uncompressed_bytes; 789 dsphys->ds_bp = origin->ds_phys->ds_bp; 790 dsphys->ds_flags |= origin->ds_phys->ds_flags; 791 792 dmu_buf_will_dirty(origin->ds_dbuf, tx); 793 origin->ds_phys->ds_num_children++; 794 795 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 796 if (origin->ds_phys->ds_next_clones_obj == 0) { 797 origin->ds_phys->ds_next_clones_obj = 798 zap_create(mos, 799 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 800 } 801 VERIFY(0 == zap_add_int(mos, 802 origin->ds_phys->ds_next_clones_obj, 803 dsobj, tx)); 804 } 805 806 dmu_buf_will_dirty(dd->dd_dbuf, tx); 807 dd->dd_phys->dd_origin_obj = origin->ds_object; 808 } 809 810 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 811 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 812 813 dmu_buf_rele(dbuf, FTAG); 814 815 dmu_buf_will_dirty(dd->dd_dbuf, tx); 816 dd->dd_phys->dd_head_dataset_obj = dsobj; 817 818 return (dsobj); 819 } 820 821 uint64_t 822 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 823 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 824 { 825 dsl_pool_t *dp = pdd->dd_pool; 826 uint64_t dsobj, ddobj; 827 dsl_dir_t *dd; 828 829 ASSERT(lastname[0] != '@'); 830 831 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 832 VERIFY(0 == dsl_dir_open_obj(dp, ddobj, lastname, FTAG, &dd)); 833 834 dsobj = dsl_dataset_create_sync_dd(dd, origin, flags, tx); 835 836 dsl_deleg_set_create_perms(dd, tx, cr); 837 838 dsl_dir_close(dd, FTAG); 839 840 return (dsobj); 841 } 842 843 struct destroyarg { 844 dsl_sync_task_group_t *dstg; 845 char *snapname; 846 char *failed; 847 }; 848 849 static int 850 dsl_snapshot_destroy_one(char *name, void *arg) 851 { 852 struct destroyarg *da = arg; 853 dsl_dataset_t *ds; 854 char *cp; 855 int err; 856 857 (void) strcat(name, "@"); 858 (void) strcat(name, da->snapname); 859 err = dsl_dataset_own(name, DS_MODE_READONLY | DS_MODE_INCONSISTENT, 860 da->dstg, &ds); 861 cp = strchr(name, '@'); 862 *cp = '\0'; 863 if (err == 0) { 864 dsl_dataset_make_exclusive(ds, da->dstg); 865 if (ds->ds_user_ptr) { 866 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 867 ds->ds_user_ptr = NULL; 868 } 869 dsl_sync_task_create(da->dstg, dsl_dataset_destroy_check, 870 dsl_dataset_destroy_sync, ds, da->dstg, 0); 871 } else if (err == ENOENT) { 872 err = 0; 873 } else { 874 (void) strcpy(da->failed, name); 875 } 876 return (err); 877 } 878 879 /* 880 * Destroy 'snapname' in all descendants of 'fsname'. 881 */ 882 #pragma weak dmu_snapshots_destroy = dsl_snapshots_destroy 883 int 884 dsl_snapshots_destroy(char *fsname, char *snapname) 885 { 886 int err; 887 struct destroyarg da; 888 dsl_sync_task_t *dst; 889 spa_t *spa; 890 891 err = spa_open(fsname, &spa, FTAG); 892 if (err) 893 return (err); 894 da.dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 895 da.snapname = snapname; 896 da.failed = fsname; 897 898 err = dmu_objset_find(fsname, 899 dsl_snapshot_destroy_one, &da, DS_FIND_CHILDREN); 900 901 if (err == 0) 902 err = dsl_sync_task_group_wait(da.dstg); 903 904 for (dst = list_head(&da.dstg->dstg_tasks); dst; 905 dst = list_next(&da.dstg->dstg_tasks, dst)) { 906 dsl_dataset_t *ds = dst->dst_arg1; 907 /* 908 * Return the file system name that triggered the error 909 */ 910 if (dst->dst_err) { 911 dsl_dataset_name(ds, fsname); 912 *strchr(fsname, '@') = '\0'; 913 } 914 dsl_dataset_disown(ds, da.dstg); 915 } 916 917 dsl_sync_task_group_destroy(da.dstg); 918 spa_close(spa, FTAG); 919 return (err); 920 } 921 922 /* 923 * ds must be opened as OWNER. On return (whether successful or not), 924 * ds will be closed and caller can no longer dereference it. 925 */ 926 int 927 dsl_dataset_destroy(dsl_dataset_t *ds, void *tag) 928 { 929 int err; 930 dsl_sync_task_group_t *dstg; 931 objset_t *os; 932 dsl_dir_t *dd; 933 uint64_t obj; 934 935 if (dsl_dataset_is_snapshot(ds)) { 936 /* Destroying a snapshot is simpler */ 937 dsl_dataset_make_exclusive(ds, tag); 938 939 if (ds->ds_user_ptr) { 940 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 941 ds->ds_user_ptr = NULL; 942 } 943 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 944 dsl_dataset_destroy_check, dsl_dataset_destroy_sync, 945 ds, tag, 0); 946 goto out; 947 } 948 949 dd = ds->ds_dir; 950 951 /* 952 * Check for errors and mark this ds as inconsistent, in 953 * case we crash while freeing the objects. 954 */ 955 err = dsl_sync_task_do(dd->dd_pool, dsl_dataset_destroy_begin_check, 956 dsl_dataset_destroy_begin_sync, ds, NULL, 0); 957 if (err) 958 goto out; 959 960 err = dmu_objset_open_ds(ds, DMU_OST_ANY, &os); 961 if (err) 962 goto out; 963 964 /* 965 * remove the objects in open context, so that we won't 966 * have too much to do in syncing context. 967 */ 968 for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 969 ds->ds_phys->ds_prev_snap_txg)) { 970 /* 971 * Ignore errors, if there is not enough disk space 972 * we will deal with it in dsl_dataset_destroy_sync(). 973 */ 974 (void) dmu_free_object(os, obj); 975 } 976 977 dmu_objset_close(os); 978 if (err != ESRCH) 979 goto out; 980 981 rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER); 982 err = dsl_dir_open_obj(dd->dd_pool, dd->dd_object, NULL, FTAG, &dd); 983 rw_exit(&dd->dd_pool->dp_config_rwlock); 984 985 if (err) 986 goto out; 987 988 if (ds->ds_user_ptr) { 989 /* 990 * We need to sync out all in-flight IO before we try 991 * to evict (the dataset evict func is trying to clear 992 * the cached entries for this dataset in the ARC). 993 */ 994 txg_wait_synced(dd->dd_pool, 0); 995 } 996 997 /* 998 * Blow away the dsl_dir + head dataset. 999 */ 1000 dsl_dataset_make_exclusive(ds, tag); 1001 if (ds->ds_user_ptr) { 1002 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1003 ds->ds_user_ptr = NULL; 1004 } 1005 dstg = dsl_sync_task_group_create(ds->ds_dir->dd_pool); 1006 dsl_sync_task_create(dstg, dsl_dataset_destroy_check, 1007 dsl_dataset_destroy_sync, ds, tag, 0); 1008 dsl_sync_task_create(dstg, dsl_dir_destroy_check, 1009 dsl_dir_destroy_sync, dd, FTAG, 0); 1010 err = dsl_sync_task_group_wait(dstg); 1011 dsl_sync_task_group_destroy(dstg); 1012 /* if it is successful, dsl_dir_destroy_sync will close the dd */ 1013 if (err) 1014 dsl_dir_close(dd, FTAG); 1015 out: 1016 dsl_dataset_disown(ds, tag); 1017 return (err); 1018 } 1019 1020 int 1021 dsl_dataset_rollback(dsl_dataset_t *ds, dmu_objset_type_t ost) 1022 { 1023 int err; 1024 1025 ASSERT(ds->ds_owner); 1026 1027 dsl_dataset_make_exclusive(ds, ds->ds_owner); 1028 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 1029 dsl_dataset_rollback_check, dsl_dataset_rollback_sync, 1030 ds, &ost, 0); 1031 /* drop exclusive access */ 1032 mutex_enter(&ds->ds_lock); 1033 rw_exit(&ds->ds_rwlock); 1034 cv_broadcast(&ds->ds_exclusive_cv); 1035 mutex_exit(&ds->ds_lock); 1036 return (err); 1037 } 1038 1039 void * 1040 dsl_dataset_set_user_ptr(dsl_dataset_t *ds, 1041 void *p, dsl_dataset_evict_func_t func) 1042 { 1043 void *old; 1044 1045 mutex_enter(&ds->ds_lock); 1046 old = ds->ds_user_ptr; 1047 if (old == NULL) { 1048 ds->ds_user_ptr = p; 1049 ds->ds_user_evict_func = func; 1050 } 1051 mutex_exit(&ds->ds_lock); 1052 return (old); 1053 } 1054 1055 void * 1056 dsl_dataset_get_user_ptr(dsl_dataset_t *ds) 1057 { 1058 return (ds->ds_user_ptr); 1059 } 1060 1061 1062 blkptr_t * 1063 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1064 { 1065 return (&ds->ds_phys->ds_bp); 1066 } 1067 1068 void 1069 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1070 { 1071 ASSERT(dmu_tx_is_syncing(tx)); 1072 /* If it's the meta-objset, set dp_meta_rootbp */ 1073 if (ds == NULL) { 1074 tx->tx_pool->dp_meta_rootbp = *bp; 1075 } else { 1076 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1077 ds->ds_phys->ds_bp = *bp; 1078 } 1079 } 1080 1081 spa_t * 1082 dsl_dataset_get_spa(dsl_dataset_t *ds) 1083 { 1084 return (ds->ds_dir->dd_pool->dp_spa); 1085 } 1086 1087 void 1088 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1089 { 1090 dsl_pool_t *dp; 1091 1092 if (ds == NULL) /* this is the meta-objset */ 1093 return; 1094 1095 ASSERT(ds->ds_user_ptr != NULL); 1096 1097 if (ds->ds_phys->ds_next_snap_obj != 0) 1098 panic("dirtying snapshot!"); 1099 1100 dp = ds->ds_dir->dd_pool; 1101 1102 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg) == 0) { 1103 /* up the hold count until we can be written out */ 1104 dmu_buf_add_ref(ds->ds_dbuf, ds); 1105 } 1106 } 1107 1108 /* 1109 * The unique space in the head dataset can be calculated by subtracting 1110 * the space used in the most recent snapshot, that is still being used 1111 * in this file system, from the space currently in use. To figure out 1112 * the space in the most recent snapshot still in use, we need to take 1113 * the total space used in the snapshot and subtract out the space that 1114 * has been freed up since the snapshot was taken. 1115 */ 1116 static void 1117 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 1118 { 1119 uint64_t mrs_used; 1120 uint64_t dlused, dlcomp, dluncomp; 1121 1122 ASSERT(ds->ds_object == ds->ds_dir->dd_phys->dd_head_dataset_obj); 1123 1124 if (ds->ds_phys->ds_prev_snap_obj != 0) 1125 mrs_used = ds->ds_prev->ds_phys->ds_used_bytes; 1126 else 1127 mrs_used = 0; 1128 1129 VERIFY(0 == bplist_space(&ds->ds_deadlist, &dlused, &dlcomp, 1130 &dluncomp)); 1131 1132 ASSERT3U(dlused, <=, mrs_used); 1133 ds->ds_phys->ds_unique_bytes = 1134 ds->ds_phys->ds_used_bytes - (mrs_used - dlused); 1135 1136 if (!DS_UNIQUE_IS_ACCURATE(ds) && 1137 spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1138 SPA_VERSION_UNIQUE_ACCURATE) 1139 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1140 } 1141 1142 static uint64_t 1143 dsl_dataset_unique(dsl_dataset_t *ds) 1144 { 1145 if (!DS_UNIQUE_IS_ACCURATE(ds) && !dsl_dataset_is_snapshot(ds)) 1146 dsl_dataset_recalc_head_uniq(ds); 1147 1148 return (ds->ds_phys->ds_unique_bytes); 1149 } 1150 1151 struct killarg { 1152 dsl_dataset_t *ds; 1153 zio_t *zio; 1154 dmu_tx_t *tx; 1155 }; 1156 1157 /* ARGSUSED */ 1158 static int 1159 kill_blkptr(spa_t *spa, blkptr_t *bp, const zbookmark_t *zb, 1160 const dnode_phys_t *dnp, void *arg) 1161 { 1162 struct killarg *ka = arg; 1163 1164 if (bp == NULL) 1165 return (0); 1166 1167 ASSERT3U(bp->blk_birth, >, ka->ds->ds_phys->ds_prev_snap_txg); 1168 (void) dsl_dataset_block_kill(ka->ds, bp, ka->zio, ka->tx); 1169 1170 return (0); 1171 } 1172 1173 /* ARGSUSED */ 1174 static int 1175 dsl_dataset_rollback_check(void *arg1, void *arg2, dmu_tx_t *tx) 1176 { 1177 dsl_dataset_t *ds = arg1; 1178 dmu_objset_type_t *ost = arg2; 1179 1180 /* 1181 * We can only roll back to emptyness if it is a ZPL objset. 1182 */ 1183 if (*ost != DMU_OST_ZFS && ds->ds_phys->ds_prev_snap_txg == 0) 1184 return (EINVAL); 1185 1186 /* 1187 * This must not be a snapshot. 1188 */ 1189 if (ds->ds_phys->ds_next_snap_obj != 0) 1190 return (EINVAL); 1191 1192 /* 1193 * If we made changes this txg, traverse_dataset won't find 1194 * them. Try again. 1195 */ 1196 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1197 return (EAGAIN); 1198 1199 return (0); 1200 } 1201 1202 /* ARGSUSED */ 1203 static void 1204 dsl_dataset_rollback_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1205 { 1206 dsl_dataset_t *ds = arg1; 1207 dmu_objset_type_t *ost = arg2; 1208 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1209 1210 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1211 1212 /* 1213 * Before the roll back destroy the zil. 1214 */ 1215 if (ds->ds_user_ptr != NULL) { 1216 zil_rollback_destroy( 1217 ((objset_impl_t *)ds->ds_user_ptr)->os_zil, tx); 1218 1219 /* 1220 * We need to make sure that the objset_impl_t is reopened after 1221 * we do the rollback, otherwise it will have the wrong 1222 * objset_phys_t. Normally this would happen when this 1223 * dataset-open is closed, thus causing the 1224 * dataset to be immediately evicted. But when doing "zfs recv 1225 * -F", we reopen the objset before that, so that there is no 1226 * window where the dataset is closed and inconsistent. 1227 */ 1228 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1229 ds->ds_user_ptr = NULL; 1230 } 1231 1232 /* Transfer space that was freed since last snap back to the head. */ 1233 { 1234 uint64_t used; 1235 1236 VERIFY(0 == bplist_space_birthrange(&ds->ds_deadlist, 1237 ds->ds_origin_txg, UINT64_MAX, &used)); 1238 dsl_dir_transfer_space(ds->ds_dir, used, 1239 DD_USED_SNAP, DD_USED_HEAD, tx); 1240 } 1241 1242 /* Zero out the deadlist. */ 1243 bplist_close(&ds->ds_deadlist); 1244 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1245 ds->ds_phys->ds_deadlist_obj = 1246 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1247 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1248 ds->ds_phys->ds_deadlist_obj)); 1249 1250 { 1251 /* Free blkptrs that we gave birth to */ 1252 zio_t *zio; 1253 struct killarg ka; 1254 1255 zio = zio_root(tx->tx_pool->dp_spa, NULL, NULL, 1256 ZIO_FLAG_MUSTSUCCEED); 1257 ka.ds = ds; 1258 ka.zio = zio; 1259 ka.tx = tx; 1260 (void) traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1261 TRAVERSE_POST, kill_blkptr, &ka); 1262 (void) zio_wait(zio); 1263 } 1264 1265 ASSERT(!(ds->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) || 1266 ds->ds_phys->ds_unique_bytes == 0); 1267 1268 if (ds->ds_prev && ds->ds_prev != ds->ds_dir->dd_pool->dp_origin_snap) { 1269 /* Change our contents to that of the prev snapshot */ 1270 1271 ASSERT3U(ds->ds_prev->ds_object, ==, 1272 ds->ds_phys->ds_prev_snap_obj); 1273 ASSERT3U(ds->ds_phys->ds_used_bytes, <=, 1274 ds->ds_prev->ds_phys->ds_used_bytes); 1275 1276 ds->ds_phys->ds_bp = ds->ds_prev->ds_phys->ds_bp; 1277 ds->ds_phys->ds_used_bytes = 1278 ds->ds_prev->ds_phys->ds_used_bytes; 1279 ds->ds_phys->ds_compressed_bytes = 1280 ds->ds_prev->ds_phys->ds_compressed_bytes; 1281 ds->ds_phys->ds_uncompressed_bytes = 1282 ds->ds_prev->ds_phys->ds_uncompressed_bytes; 1283 ds->ds_phys->ds_flags = ds->ds_prev->ds_phys->ds_flags; 1284 1285 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1286 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1287 ds->ds_prev->ds_phys->ds_unique_bytes = 0; 1288 } 1289 } else { 1290 objset_impl_t *osi; 1291 1292 ASSERT3U(ds->ds_phys->ds_used_bytes, ==, 0); 1293 ASSERT3U(ds->ds_phys->ds_compressed_bytes, ==, 0); 1294 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, ==, 0); 1295 1296 bzero(&ds->ds_phys->ds_bp, sizeof (blkptr_t)); 1297 ds->ds_phys->ds_flags = 0; 1298 ds->ds_phys->ds_unique_bytes = 0; 1299 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1300 SPA_VERSION_UNIQUE_ACCURATE) 1301 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1302 1303 osi = dmu_objset_create_impl(ds->ds_dir->dd_pool->dp_spa, ds, 1304 &ds->ds_phys->ds_bp, *ost, tx); 1305 #ifdef _KERNEL 1306 zfs_create_fs(&osi->os, kcred, NULL, tx); 1307 #endif 1308 } 1309 1310 spa_history_internal_log(LOG_DS_ROLLBACK, ds->ds_dir->dd_pool->dp_spa, 1311 tx, cr, "dataset = %llu", ds->ds_object); 1312 } 1313 1314 /* ARGSUSED */ 1315 static int 1316 dsl_dataset_destroy_begin_check(void *arg1, void *arg2, dmu_tx_t *tx) 1317 { 1318 dsl_dataset_t *ds = arg1; 1319 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1320 uint64_t count; 1321 int err; 1322 1323 /* 1324 * Can't delete a head dataset if there are snapshots of it. 1325 * (Except if the only snapshots are from the branch we cloned 1326 * from.) 1327 */ 1328 if (ds->ds_prev != NULL && 1329 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1330 return (EINVAL); 1331 1332 /* 1333 * This is really a dsl_dir thing, but check it here so that 1334 * we'll be less likely to leave this dataset inconsistent & 1335 * nearly destroyed. 1336 */ 1337 err = zap_count(mos, ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count); 1338 if (err) 1339 return (err); 1340 if (count != 0) 1341 return (EEXIST); 1342 1343 return (0); 1344 } 1345 1346 /* ARGSUSED */ 1347 static void 1348 dsl_dataset_destroy_begin_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1349 { 1350 dsl_dataset_t *ds = arg1; 1351 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1352 1353 /* Mark it as inconsistent on-disk, in case we crash */ 1354 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1355 ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT; 1356 1357 spa_history_internal_log(LOG_DS_DESTROY_BEGIN, dp->dp_spa, tx, 1358 cr, "dataset = %llu", ds->ds_object); 1359 } 1360 1361 /* ARGSUSED */ 1362 int 1363 dsl_dataset_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx) 1364 { 1365 dsl_dataset_t *ds = arg1; 1366 1367 /* we have an owner hold, so noone else can destroy us */ 1368 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 1369 1370 /* Can't delete a branch point. */ 1371 if (ds->ds_phys->ds_num_children > 1) 1372 return (EEXIST); 1373 1374 /* 1375 * Can't delete a head dataset if there are snapshots of it. 1376 * (Except if the only snapshots are from the branch we cloned 1377 * from.) 1378 */ 1379 if (ds->ds_prev != NULL && 1380 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1381 return (EINVAL); 1382 1383 /* 1384 * If we made changes this txg, traverse_dsl_dataset won't find 1385 * them. Try again. 1386 */ 1387 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1388 return (EAGAIN); 1389 1390 /* XXX we should do some i/o error checking... */ 1391 return (0); 1392 } 1393 1394 struct refsarg { 1395 kmutex_t lock; 1396 boolean_t gone; 1397 kcondvar_t cv; 1398 }; 1399 1400 /* ARGSUSED */ 1401 static void 1402 dsl_dataset_refs_gone(dmu_buf_t *db, void *argv) 1403 { 1404 struct refsarg *arg = argv; 1405 1406 mutex_enter(&arg->lock); 1407 arg->gone = TRUE; 1408 cv_signal(&arg->cv); 1409 mutex_exit(&arg->lock); 1410 } 1411 1412 static void 1413 dsl_dataset_drain_refs(dsl_dataset_t *ds, void *tag) 1414 { 1415 struct refsarg arg; 1416 1417 mutex_init(&arg.lock, NULL, MUTEX_DEFAULT, NULL); 1418 cv_init(&arg.cv, NULL, CV_DEFAULT, NULL); 1419 arg.gone = FALSE; 1420 (void) dmu_buf_update_user(ds->ds_dbuf, ds, &arg, &ds->ds_phys, 1421 dsl_dataset_refs_gone); 1422 dmu_buf_rele(ds->ds_dbuf, tag); 1423 mutex_enter(&arg.lock); 1424 while (!arg.gone) 1425 cv_wait(&arg.cv, &arg.lock); 1426 ASSERT(arg.gone); 1427 mutex_exit(&arg.lock); 1428 ds->ds_dbuf = NULL; 1429 ds->ds_phys = NULL; 1430 mutex_destroy(&arg.lock); 1431 cv_destroy(&arg.cv); 1432 } 1433 1434 void 1435 dsl_dataset_destroy_sync(void *arg1, void *tag, cred_t *cr, dmu_tx_t *tx) 1436 { 1437 dsl_dataset_t *ds = arg1; 1438 zio_t *zio; 1439 int err; 1440 int after_branch_point = FALSE; 1441 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1442 objset_t *mos = dp->dp_meta_objset; 1443 dsl_dataset_t *ds_prev = NULL; 1444 uint64_t obj; 1445 1446 ASSERT(ds->ds_owner); 1447 ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); 1448 ASSERT(ds->ds_prev == NULL || 1449 ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object); 1450 ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); 1451 1452 /* signal any waiters that this dataset is going away */ 1453 mutex_enter(&ds->ds_lock); 1454 ds->ds_owner = dsl_reaper; 1455 cv_broadcast(&ds->ds_exclusive_cv); 1456 mutex_exit(&ds->ds_lock); 1457 1458 /* Remove our reservation */ 1459 if (ds->ds_reserved != 0) { 1460 uint64_t val = 0; 1461 dsl_dataset_set_reservation_sync(ds, &val, cr, tx); 1462 ASSERT3U(ds->ds_reserved, ==, 0); 1463 } 1464 1465 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1466 1467 dsl_pool_ds_destroyed(ds, tx); 1468 1469 obj = ds->ds_object; 1470 1471 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1472 if (ds->ds_prev) { 1473 ds_prev = ds->ds_prev; 1474 } else { 1475 VERIFY(0 == dsl_dataset_hold_obj(dp, 1476 ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev)); 1477 } 1478 after_branch_point = 1479 (ds_prev->ds_phys->ds_next_snap_obj != obj); 1480 1481 dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); 1482 if (after_branch_point && 1483 ds_prev->ds_phys->ds_next_clones_obj != 0) { 1484 VERIFY(0 == zap_remove_int(mos, 1485 ds_prev->ds_phys->ds_next_clones_obj, obj, tx)); 1486 if (ds->ds_phys->ds_next_snap_obj != 0) { 1487 VERIFY(0 == zap_add_int(mos, 1488 ds_prev->ds_phys->ds_next_clones_obj, 1489 ds->ds_phys->ds_next_snap_obj, tx)); 1490 } 1491 } 1492 if (after_branch_point && 1493 ds->ds_phys->ds_next_snap_obj == 0) { 1494 /* This clone is toast. */ 1495 ASSERT(ds_prev->ds_phys->ds_num_children > 1); 1496 ds_prev->ds_phys->ds_num_children--; 1497 } else if (!after_branch_point) { 1498 ds_prev->ds_phys->ds_next_snap_obj = 1499 ds->ds_phys->ds_next_snap_obj; 1500 } 1501 } 1502 1503 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 1504 1505 if (ds->ds_phys->ds_next_snap_obj != 0) { 1506 blkptr_t bp; 1507 dsl_dataset_t *ds_next; 1508 uint64_t itor = 0; 1509 uint64_t old_unique; 1510 int64_t used = 0, compressed = 0, uncompressed = 0; 1511 1512 VERIFY(0 == dsl_dataset_hold_obj(dp, 1513 ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next)); 1514 ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj); 1515 1516 old_unique = dsl_dataset_unique(ds_next); 1517 1518 dmu_buf_will_dirty(ds_next->ds_dbuf, tx); 1519 ds_next->ds_phys->ds_prev_snap_obj = 1520 ds->ds_phys->ds_prev_snap_obj; 1521 ds_next->ds_phys->ds_prev_snap_txg = 1522 ds->ds_phys->ds_prev_snap_txg; 1523 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1524 ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0); 1525 1526 /* 1527 * Transfer to our deadlist (which will become next's 1528 * new deadlist) any entries from next's current 1529 * deadlist which were born before prev, and free the 1530 * other entries. 1531 * 1532 * XXX we're doing this long task with the config lock held 1533 */ 1534 while (bplist_iterate(&ds_next->ds_deadlist, &itor, &bp) == 0) { 1535 if (bp.blk_birth <= ds->ds_phys->ds_prev_snap_txg) { 1536 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, 1537 &bp, tx)); 1538 if (ds_prev && !after_branch_point && 1539 bp.blk_birth > 1540 ds_prev->ds_phys->ds_prev_snap_txg) { 1541 ds_prev->ds_phys->ds_unique_bytes += 1542 bp_get_dasize(dp->dp_spa, &bp); 1543 } 1544 } else { 1545 used += bp_get_dasize(dp->dp_spa, &bp); 1546 compressed += BP_GET_PSIZE(&bp); 1547 uncompressed += BP_GET_UCSIZE(&bp); 1548 /* XXX check return value? */ 1549 (void) dsl_free(zio, dp, tx->tx_txg, 1550 &bp, NULL, NULL, ARC_NOWAIT); 1551 } 1552 } 1553 1554 ASSERT3U(used, ==, ds->ds_phys->ds_unique_bytes); 1555 1556 /* change snapused */ 1557 dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP, 1558 -used, -compressed, -uncompressed, tx); 1559 1560 /* free next's deadlist */ 1561 bplist_close(&ds_next->ds_deadlist); 1562 bplist_destroy(mos, ds_next->ds_phys->ds_deadlist_obj, tx); 1563 1564 /* set next's deadlist to our deadlist */ 1565 bplist_close(&ds->ds_deadlist); 1566 ds_next->ds_phys->ds_deadlist_obj = 1567 ds->ds_phys->ds_deadlist_obj; 1568 VERIFY(0 == bplist_open(&ds_next->ds_deadlist, mos, 1569 ds_next->ds_phys->ds_deadlist_obj)); 1570 ds->ds_phys->ds_deadlist_obj = 0; 1571 1572 if (ds_next->ds_phys->ds_next_snap_obj != 0) { 1573 /* 1574 * Update next's unique to include blocks which 1575 * were previously shared by only this snapshot 1576 * and it. Those blocks will be born after the 1577 * prev snap and before this snap, and will have 1578 * died after the next snap and before the one 1579 * after that (ie. be on the snap after next's 1580 * deadlist). 1581 * 1582 * XXX we're doing this long task with the 1583 * config lock held 1584 */ 1585 dsl_dataset_t *ds_after_next; 1586 uint64_t space; 1587 1588 VERIFY(0 == dsl_dataset_hold_obj(dp, 1589 ds_next->ds_phys->ds_next_snap_obj, 1590 FTAG, &ds_after_next)); 1591 1592 VERIFY(0 == 1593 bplist_space_birthrange(&ds_after_next->ds_deadlist, 1594 ds->ds_phys->ds_prev_snap_txg, 1595 ds->ds_phys->ds_creation_txg, &space)); 1596 ds_next->ds_phys->ds_unique_bytes += space; 1597 1598 dsl_dataset_rele(ds_after_next, FTAG); 1599 ASSERT3P(ds_next->ds_prev, ==, NULL); 1600 } else { 1601 ASSERT3P(ds_next->ds_prev, ==, ds); 1602 dsl_dataset_drop_ref(ds_next->ds_prev, ds_next); 1603 ds_next->ds_prev = NULL; 1604 if (ds_prev) { 1605 VERIFY(0 == dsl_dataset_get_ref(dp, 1606 ds->ds_phys->ds_prev_snap_obj, 1607 ds_next, &ds_next->ds_prev)); 1608 } 1609 1610 dsl_dataset_recalc_head_uniq(ds_next); 1611 1612 /* 1613 * Reduce the amount of our unconsmed refreservation 1614 * being charged to our parent by the amount of 1615 * new unique data we have gained. 1616 */ 1617 if (old_unique < ds_next->ds_reserved) { 1618 int64_t mrsdelta; 1619 uint64_t new_unique = 1620 ds_next->ds_phys->ds_unique_bytes; 1621 1622 ASSERT(old_unique <= new_unique); 1623 mrsdelta = MIN(new_unique - old_unique, 1624 ds_next->ds_reserved - old_unique); 1625 dsl_dir_diduse_space(ds->ds_dir, 1626 DD_USED_REFRSRV, -mrsdelta, 0, 0, tx); 1627 } 1628 } 1629 dsl_dataset_rele(ds_next, FTAG); 1630 } else { 1631 /* 1632 * There's no next snapshot, so this is a head dataset. 1633 * Destroy the deadlist. Unless it's a clone, the 1634 * deadlist should be empty. (If it's a clone, it's 1635 * safe to ignore the deadlist contents.) 1636 */ 1637 struct killarg ka; 1638 1639 ASSERT(after_branch_point || bplist_empty(&ds->ds_deadlist)); 1640 bplist_close(&ds->ds_deadlist); 1641 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1642 ds->ds_phys->ds_deadlist_obj = 0; 1643 1644 /* 1645 * Free everything that we point to (that's born after 1646 * the previous snapshot, if we are a clone) 1647 * 1648 * NB: this should be very quick, because we already 1649 * freed all the objects in open context. 1650 */ 1651 ka.ds = ds; 1652 ka.zio = zio; 1653 ka.tx = tx; 1654 err = traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1655 TRAVERSE_POST, kill_blkptr, &ka); 1656 ASSERT3U(err, ==, 0); 1657 ASSERT(spa_version(dp->dp_spa) < SPA_VERSION_UNIQUE_ACCURATE || 1658 ds->ds_phys->ds_unique_bytes == 0); 1659 } 1660 1661 err = zio_wait(zio); 1662 ASSERT3U(err, ==, 0); 1663 1664 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == ds->ds_object) { 1665 /* Erase the link in the dir */ 1666 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); 1667 ds->ds_dir->dd_phys->dd_head_dataset_obj = 0; 1668 ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0); 1669 err = zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx); 1670 ASSERT(err == 0); 1671 } else { 1672 /* remove from snapshot namespace */ 1673 dsl_dataset_t *ds_head; 1674 ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0); 1675 VERIFY(0 == dsl_dataset_hold_obj(dp, 1676 ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head)); 1677 VERIFY(0 == dsl_dataset_get_snapname(ds)); 1678 #ifdef ZFS_DEBUG 1679 { 1680 uint64_t val; 1681 1682 err = dsl_dataset_snap_lookup(ds_head, 1683 ds->ds_snapname, &val); 1684 ASSERT3U(err, ==, 0); 1685 ASSERT3U(val, ==, obj); 1686 } 1687 #endif 1688 err = dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx); 1689 ASSERT(err == 0); 1690 dsl_dataset_rele(ds_head, FTAG); 1691 } 1692 1693 if (ds_prev && ds->ds_prev != ds_prev) 1694 dsl_dataset_rele(ds_prev, FTAG); 1695 1696 spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); 1697 spa_history_internal_log(LOG_DS_DESTROY, dp->dp_spa, tx, 1698 cr, "dataset = %llu", ds->ds_object); 1699 1700 if (ds->ds_phys->ds_next_clones_obj != 0) { 1701 uint64_t count; 1702 ASSERT(0 == zap_count(mos, 1703 ds->ds_phys->ds_next_clones_obj, &count) && count == 0); 1704 VERIFY(0 == dmu_object_free(mos, 1705 ds->ds_phys->ds_next_clones_obj, tx)); 1706 } 1707 if (ds->ds_phys->ds_props_obj != 0) 1708 VERIFY(0 == zap_destroy(mos, ds->ds_phys->ds_props_obj, tx)); 1709 dsl_dir_close(ds->ds_dir, ds); 1710 ds->ds_dir = NULL; 1711 dsl_dataset_drain_refs(ds, tag); 1712 VERIFY(0 == dmu_object_free(mos, obj, tx)); 1713 } 1714 1715 static int 1716 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1717 { 1718 uint64_t asize; 1719 1720 if (!dmu_tx_is_syncing(tx)) 1721 return (0); 1722 1723 /* 1724 * If there's an fs-only reservation, any blocks that might become 1725 * owned by the snapshot dataset must be accommodated by space 1726 * outside of the reservation. 1727 */ 1728 asize = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1729 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, FALSE)) 1730 return (ENOSPC); 1731 1732 /* 1733 * Propogate any reserved space for this snapshot to other 1734 * snapshot checks in this sync group. 1735 */ 1736 if (asize > 0) 1737 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1738 1739 return (0); 1740 } 1741 1742 /* ARGSUSED */ 1743 int 1744 dsl_dataset_snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx) 1745 { 1746 dsl_dataset_t *ds = arg1; 1747 const char *snapname = arg2; 1748 int err; 1749 uint64_t value; 1750 1751 /* 1752 * We don't allow multiple snapshots of the same txg. If there 1753 * is already one, try again. 1754 */ 1755 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 1756 return (EAGAIN); 1757 1758 /* 1759 * Check for conflicting name snapshot name. 1760 */ 1761 err = dsl_dataset_snap_lookup(ds, snapname, &value); 1762 if (err == 0) 1763 return (EEXIST); 1764 if (err != ENOENT) 1765 return (err); 1766 1767 /* 1768 * Check that the dataset's name is not too long. Name consists 1769 * of the dataset's length + 1 for the @-sign + snapshot name's length 1770 */ 1771 if (dsl_dataset_namelen(ds) + 1 + strlen(snapname) >= MAXNAMELEN) 1772 return (ENAMETOOLONG); 1773 1774 err = dsl_dataset_snapshot_reserve_space(ds, tx); 1775 if (err) 1776 return (err); 1777 1778 ds->ds_trysnap_txg = tx->tx_txg; 1779 return (0); 1780 } 1781 1782 void 1783 dsl_dataset_snapshot_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1784 { 1785 dsl_dataset_t *ds = arg1; 1786 const char *snapname = arg2; 1787 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1788 dmu_buf_t *dbuf; 1789 dsl_dataset_phys_t *dsphys; 1790 uint64_t dsobj, crtxg; 1791 objset_t *mos = dp->dp_meta_objset; 1792 int err; 1793 1794 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1795 1796 /* 1797 * The origin's ds_creation_txg has to be < TXG_INITIAL 1798 */ 1799 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1800 crtxg = 1; 1801 else 1802 crtxg = tx->tx_txg; 1803 1804 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1805 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1806 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1807 dmu_buf_will_dirty(dbuf, tx); 1808 dsphys = dbuf->db_data; 1809 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1810 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1811 dsphys->ds_fsid_guid = unique_create(); 1812 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1813 sizeof (dsphys->ds_guid)); 1814 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1815 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1816 dsphys->ds_next_snap_obj = ds->ds_object; 1817 dsphys->ds_num_children = 1; 1818 dsphys->ds_creation_time = gethrestime_sec(); 1819 dsphys->ds_creation_txg = crtxg; 1820 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1821 dsphys->ds_used_bytes = ds->ds_phys->ds_used_bytes; 1822 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1823 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1824 dsphys->ds_flags = ds->ds_phys->ds_flags; 1825 dsphys->ds_bp = ds->ds_phys->ds_bp; 1826 dmu_buf_rele(dbuf, FTAG); 1827 1828 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1829 if (ds->ds_prev) { 1830 uint64_t next_clones_obj = 1831 ds->ds_prev->ds_phys->ds_next_clones_obj; 1832 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1833 ds->ds_object || 1834 ds->ds_prev->ds_phys->ds_num_children > 1); 1835 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1836 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1837 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1838 ds->ds_prev->ds_phys->ds_creation_txg); 1839 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1840 } else if (next_clones_obj != 0) { 1841 VERIFY3U(0, ==, zap_remove_int(mos, 1842 next_clones_obj, dsphys->ds_next_snap_obj, tx)); 1843 VERIFY3U(0, ==, zap_add_int(mos, 1844 next_clones_obj, dsobj, tx)); 1845 } 1846 } 1847 1848 /* 1849 * If we have a reference-reservation on this dataset, we will 1850 * need to increase the amount of refreservation being charged 1851 * since our unique space is going to zero. 1852 */ 1853 if (ds->ds_reserved) { 1854 int64_t add = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1855 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1856 add, 0, 0, tx); 1857 } 1858 1859 bplist_close(&ds->ds_deadlist); 1860 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1861 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1862 ds->ds_phys->ds_prev_snap_obj = dsobj; 1863 ds->ds_phys->ds_prev_snap_txg = crtxg; 1864 ds->ds_phys->ds_unique_bytes = 0; 1865 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1866 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1867 ds->ds_phys->ds_deadlist_obj = 1868 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1869 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1870 ds->ds_phys->ds_deadlist_obj)); 1871 1872 dprintf("snap '%s' -> obj %llu\n", snapname, dsobj); 1873 err = zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1874 snapname, 8, 1, &dsobj, tx); 1875 ASSERT(err == 0); 1876 1877 if (ds->ds_prev) 1878 dsl_dataset_drop_ref(ds->ds_prev, ds); 1879 VERIFY(0 == dsl_dataset_get_ref(dp, 1880 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1881 1882 dsl_pool_ds_snapshotted(ds, tx); 1883 1884 spa_history_internal_log(LOG_DS_SNAPSHOT, dp->dp_spa, tx, cr, 1885 "dataset = %llu", dsobj); 1886 } 1887 1888 void 1889 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1890 { 1891 ASSERT(dmu_tx_is_syncing(tx)); 1892 ASSERT(ds->ds_user_ptr != NULL); 1893 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1894 1895 /* 1896 * in case we had to change ds_fsid_guid when we opened it, 1897 * sync it out now. 1898 */ 1899 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1900 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1901 1902 dsl_dir_dirty(ds->ds_dir, tx); 1903 dmu_objset_sync(ds->ds_user_ptr, zio, tx); 1904 } 1905 1906 void 1907 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1908 { 1909 uint64_t refd, avail, uobjs, aobjs; 1910 1911 dsl_dir_stats(ds->ds_dir, nv); 1912 1913 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1914 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1915 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1916 1917 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1918 ds->ds_phys->ds_creation_time); 1919 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1920 ds->ds_phys->ds_creation_txg); 1921 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1922 ds->ds_quota); 1923 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1924 ds->ds_reserved); 1925 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1926 ds->ds_phys->ds_guid); 1927 1928 if (ds->ds_phys->ds_next_snap_obj) { 1929 /* 1930 * This is a snapshot; override the dd's space used with 1931 * our unique space and compression ratio. 1932 */ 1933 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1934 ds->ds_phys->ds_unique_bytes); 1935 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, 1936 ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1937 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1938 ds->ds_phys->ds_compressed_bytes)); 1939 } 1940 } 1941 1942 void 1943 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1944 { 1945 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1946 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1947 stat->dds_guid = ds->ds_phys->ds_guid; 1948 if (ds->ds_phys->ds_next_snap_obj) { 1949 stat->dds_is_snapshot = B_TRUE; 1950 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1951 } 1952 1953 /* clone origin is really a dsl_dir thing... */ 1954 rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER); 1955 if (dsl_dir_is_clone(ds->ds_dir)) { 1956 dsl_dataset_t *ods; 1957 1958 VERIFY(0 == dsl_dataset_get_ref(ds->ds_dir->dd_pool, 1959 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1960 dsl_dataset_name(ods, stat->dds_origin); 1961 dsl_dataset_drop_ref(ods, FTAG); 1962 } 1963 rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock); 1964 } 1965 1966 uint64_t 1967 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1968 { 1969 return (ds->ds_fsid_guid); 1970 } 1971 1972 void 1973 dsl_dataset_space(dsl_dataset_t *ds, 1974 uint64_t *refdbytesp, uint64_t *availbytesp, 1975 uint64_t *usedobjsp, uint64_t *availobjsp) 1976 { 1977 *refdbytesp = ds->ds_phys->ds_used_bytes; 1978 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1979 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1980 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1981 if (ds->ds_quota != 0) { 1982 /* 1983 * Adjust available bytes according to refquota 1984 */ 1985 if (*refdbytesp < ds->ds_quota) 1986 *availbytesp = MIN(*availbytesp, 1987 ds->ds_quota - *refdbytesp); 1988 else 1989 *availbytesp = 0; 1990 } 1991 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1992 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1993 } 1994 1995 boolean_t 1996 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds) 1997 { 1998 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1999 2000 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 2001 dsl_pool_sync_context(dp)); 2002 if (ds->ds_prev == NULL) 2003 return (B_FALSE); 2004 if (ds->ds_phys->ds_bp.blk_birth > 2005 ds->ds_prev->ds_phys->ds_creation_txg) 2006 return (B_TRUE); 2007 return (B_FALSE); 2008 } 2009 2010 /* ARGSUSED */ 2011 static int 2012 dsl_dataset_snapshot_rename_check(void *arg1, void *arg2, dmu_tx_t *tx) 2013 { 2014 dsl_dataset_t *ds = arg1; 2015 char *newsnapname = arg2; 2016 dsl_dir_t *dd = ds->ds_dir; 2017 dsl_dataset_t *hds; 2018 uint64_t val; 2019 int err; 2020 2021 err = dsl_dataset_hold_obj(dd->dd_pool, 2022 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds); 2023 if (err) 2024 return (err); 2025 2026 /* new name better not be in use */ 2027 err = dsl_dataset_snap_lookup(hds, newsnapname, &val); 2028 dsl_dataset_rele(hds, FTAG); 2029 2030 if (err == 0) 2031 err = EEXIST; 2032 else if (err == ENOENT) 2033 err = 0; 2034 2035 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2036 if (dsl_dir_namelen(ds->ds_dir) + 1 + strlen(newsnapname) >= MAXNAMELEN) 2037 err = ENAMETOOLONG; 2038 2039 return (err); 2040 } 2041 2042 static void 2043 dsl_dataset_snapshot_rename_sync(void *arg1, void *arg2, 2044 cred_t *cr, dmu_tx_t *tx) 2045 { 2046 dsl_dataset_t *ds = arg1; 2047 const char *newsnapname = arg2; 2048 dsl_dir_t *dd = ds->ds_dir; 2049 objset_t *mos = dd->dd_pool->dp_meta_objset; 2050 dsl_dataset_t *hds; 2051 int err; 2052 2053 ASSERT(ds->ds_phys->ds_next_snap_obj != 0); 2054 2055 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, 2056 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds)); 2057 2058 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2059 err = dsl_dataset_snap_remove(hds, ds->ds_snapname, tx); 2060 ASSERT3U(err, ==, 0); 2061 mutex_enter(&ds->ds_lock); 2062 (void) strcpy(ds->ds_snapname, newsnapname); 2063 mutex_exit(&ds->ds_lock); 2064 err = zap_add(mos, hds->ds_phys->ds_snapnames_zapobj, 2065 ds->ds_snapname, 8, 1, &ds->ds_object, tx); 2066 ASSERT3U(err, ==, 0); 2067 2068 spa_history_internal_log(LOG_DS_RENAME, dd->dd_pool->dp_spa, tx, 2069 cr, "dataset = %llu", ds->ds_object); 2070 dsl_dataset_rele(hds, FTAG); 2071 } 2072 2073 struct renamesnaparg { 2074 dsl_sync_task_group_t *dstg; 2075 char failed[MAXPATHLEN]; 2076 char *oldsnap; 2077 char *newsnap; 2078 }; 2079 2080 static int 2081 dsl_snapshot_rename_one(char *name, void *arg) 2082 { 2083 struct renamesnaparg *ra = arg; 2084 dsl_dataset_t *ds = NULL; 2085 char *cp; 2086 int err; 2087 2088 cp = name + strlen(name); 2089 *cp = '@'; 2090 (void) strcpy(cp + 1, ra->oldsnap); 2091 2092 /* 2093 * For recursive snapshot renames the parent won't be changing 2094 * so we just pass name for both the to/from argument. 2095 */ 2096 err = zfs_secpolicy_rename_perms(name, name, CRED()); 2097 if (err == ENOENT) { 2098 return (0); 2099 } else if (err) { 2100 (void) strcpy(ra->failed, name); 2101 return (err); 2102 } 2103 2104 #ifdef _KERNEL 2105 /* 2106 * For all filesystems undergoing rename, we'll need to unmount it. 2107 */ 2108 (void) zfs_unmount_snap(name, NULL); 2109 #endif 2110 err = dsl_dataset_hold(name, ra->dstg, &ds); 2111 *cp = '\0'; 2112 if (err == ENOENT) { 2113 return (0); 2114 } else if (err) { 2115 (void) strcpy(ra->failed, name); 2116 return (err); 2117 } 2118 2119 dsl_sync_task_create(ra->dstg, dsl_dataset_snapshot_rename_check, 2120 dsl_dataset_snapshot_rename_sync, ds, ra->newsnap, 0); 2121 2122 return (0); 2123 } 2124 2125 static int 2126 dsl_recursive_rename(char *oldname, const char *newname) 2127 { 2128 int err; 2129 struct renamesnaparg *ra; 2130 dsl_sync_task_t *dst; 2131 spa_t *spa; 2132 char *cp, *fsname = spa_strdup(oldname); 2133 int len = strlen(oldname); 2134 2135 /* truncate the snapshot name to get the fsname */ 2136 cp = strchr(fsname, '@'); 2137 *cp = '\0'; 2138 2139 err = spa_open(fsname, &spa, FTAG); 2140 if (err) { 2141 kmem_free(fsname, len + 1); 2142 return (err); 2143 } 2144 ra = kmem_alloc(sizeof (struct renamesnaparg), KM_SLEEP); 2145 ra->dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 2146 2147 ra->oldsnap = strchr(oldname, '@') + 1; 2148 ra->newsnap = strchr(newname, '@') + 1; 2149 *ra->failed = '\0'; 2150 2151 err = dmu_objset_find(fsname, dsl_snapshot_rename_one, ra, 2152 DS_FIND_CHILDREN); 2153 kmem_free(fsname, len + 1); 2154 2155 if (err == 0) { 2156 err = dsl_sync_task_group_wait(ra->dstg); 2157 } 2158 2159 for (dst = list_head(&ra->dstg->dstg_tasks); dst; 2160 dst = list_next(&ra->dstg->dstg_tasks, dst)) { 2161 dsl_dataset_t *ds = dst->dst_arg1; 2162 if (dst->dst_err) { 2163 dsl_dir_name(ds->ds_dir, ra->failed); 2164 (void) strcat(ra->failed, "@"); 2165 (void) strcat(ra->failed, ra->newsnap); 2166 } 2167 dsl_dataset_rele(ds, ra->dstg); 2168 } 2169 2170 if (err) 2171 (void) strcpy(oldname, ra->failed); 2172 2173 dsl_sync_task_group_destroy(ra->dstg); 2174 kmem_free(ra, sizeof (struct renamesnaparg)); 2175 spa_close(spa, FTAG); 2176 return (err); 2177 } 2178 2179 static int 2180 dsl_valid_rename(char *oldname, void *arg) 2181 { 2182 int delta = *(int *)arg; 2183 2184 if (strlen(oldname) + delta >= MAXNAMELEN) 2185 return (ENAMETOOLONG); 2186 2187 return (0); 2188 } 2189 2190 #pragma weak dmu_objset_rename = dsl_dataset_rename 2191 int 2192 dsl_dataset_rename(char *oldname, const char *newname, boolean_t recursive) 2193 { 2194 dsl_dir_t *dd; 2195 dsl_dataset_t *ds; 2196 const char *tail; 2197 int err; 2198 2199 err = dsl_dir_open(oldname, FTAG, &dd, &tail); 2200 if (err) 2201 return (err); 2202 if (tail == NULL) { 2203 int delta = strlen(newname) - strlen(oldname); 2204 2205 /* if we're growing, validate child name lengths */ 2206 if (delta > 0) 2207 err = dmu_objset_find(oldname, dsl_valid_rename, 2208 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS); 2209 2210 if (!err) 2211 err = dsl_dir_rename(dd, newname); 2212 dsl_dir_close(dd, FTAG); 2213 return (err); 2214 } 2215 if (tail[0] != '@') { 2216 /* the name ended in a nonexistant component */ 2217 dsl_dir_close(dd, FTAG); 2218 return (ENOENT); 2219 } 2220 2221 dsl_dir_close(dd, FTAG); 2222 2223 /* new name must be snapshot in same filesystem */ 2224 tail = strchr(newname, '@'); 2225 if (tail == NULL) 2226 return (EINVAL); 2227 tail++; 2228 if (strncmp(oldname, newname, tail - newname) != 0) 2229 return (EXDEV); 2230 2231 if (recursive) { 2232 err = dsl_recursive_rename(oldname, newname); 2233 } else { 2234 err = dsl_dataset_hold(oldname, FTAG, &ds); 2235 if (err) 2236 return (err); 2237 2238 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2239 dsl_dataset_snapshot_rename_check, 2240 dsl_dataset_snapshot_rename_sync, ds, (char *)tail, 1); 2241 2242 dsl_dataset_rele(ds, FTAG); 2243 } 2244 2245 return (err); 2246 } 2247 2248 struct promotenode { 2249 list_node_t link; 2250 dsl_dataset_t *ds; 2251 }; 2252 2253 struct promotearg { 2254 list_t shared_snaps, origin_snaps, clone_snaps; 2255 dsl_dataset_t *origin_origin, *origin_head; 2256 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2257 }; 2258 2259 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2260 2261 /* ARGSUSED */ 2262 static int 2263 dsl_dataset_promote_check(void *arg1, void *arg2, dmu_tx_t *tx) 2264 { 2265 dsl_dataset_t *hds = arg1; 2266 struct promotearg *pa = arg2; 2267 struct promotenode *snap = list_head(&pa->shared_snaps); 2268 dsl_dataset_t *origin_ds = snap->ds; 2269 int err; 2270 2271 /* Check that it is a real clone */ 2272 if (!dsl_dir_is_clone(hds->ds_dir)) 2273 return (EINVAL); 2274 2275 /* Since this is so expensive, don't do the preliminary check */ 2276 if (!dmu_tx_is_syncing(tx)) 2277 return (0); 2278 2279 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) 2280 return (EXDEV); 2281 2282 /* compute origin's new unique space */ 2283 snap = list_tail(&pa->clone_snaps); 2284 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2285 err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2286 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, &pa->unique); 2287 if (err) 2288 return (err); 2289 2290 /* 2291 * Walk the snapshots that we are moving 2292 * 2293 * Compute space to transfer. Consider the incremental changes 2294 * to used for each snapshot: 2295 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2296 * So each snapshot gave birth to: 2297 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2298 * So a sequence would look like: 2299 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2300 * Which simplifies to: 2301 * uN + kN + kN-1 + ... + k1 + k0 2302 * Note however, if we stop before we reach the ORIGIN we get: 2303 * uN + kN + kN-1 + ... + kM - uM-1 2304 */ 2305 pa->used = origin_ds->ds_phys->ds_used_bytes; 2306 pa->comp = origin_ds->ds_phys->ds_compressed_bytes; 2307 pa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 2308 for (snap = list_head(&pa->shared_snaps); snap; 2309 snap = list_next(&pa->shared_snaps, snap)) { 2310 uint64_t val, dlused, dlcomp, dluncomp; 2311 dsl_dataset_t *ds = snap->ds; 2312 2313 /* Check that the snapshot name does not conflict */ 2314 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2315 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2316 if (err == 0) 2317 return (EEXIST); 2318 if (err != ENOENT) 2319 return (err); 2320 2321 /* The very first snapshot does not have a deadlist */ 2322 if (ds->ds_phys->ds_prev_snap_obj == 0) 2323 continue; 2324 2325 if (err = bplist_space(&ds->ds_deadlist, 2326 &dlused, &dlcomp, &dluncomp)) 2327 return (err); 2328 pa->used += dlused; 2329 pa->comp += dlcomp; 2330 pa->uncomp += dluncomp; 2331 } 2332 2333 /* 2334 * If we are a clone of a clone then we never reached ORIGIN, 2335 * so we need to subtract out the clone origin's used space. 2336 */ 2337 if (pa->origin_origin) { 2338 pa->used -= pa->origin_origin->ds_phys->ds_used_bytes; 2339 pa->comp -= pa->origin_origin->ds_phys->ds_compressed_bytes; 2340 pa->uncomp -= pa->origin_origin->ds_phys->ds_uncompressed_bytes; 2341 } 2342 2343 /* Check that there is enough space here */ 2344 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2345 pa->used); 2346 if (err) 2347 return (err); 2348 2349 /* 2350 * Compute the amounts of space that will be used by snapshots 2351 * after the promotion (for both origin and clone). For each, 2352 * it is the amount of space that will be on all of their 2353 * deadlists (that was not born before their new origin). 2354 */ 2355 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2356 uint64_t space; 2357 2358 /* 2359 * Note, typically this will not be a clone of a clone, 2360 * so snap->ds->ds_origin_txg will be < TXG_INITIAL, so 2361 * these snaplist_space() -> bplist_space_birthrange() 2362 * calls will be fast because they do not have to 2363 * iterate over all bps. 2364 */ 2365 snap = list_head(&pa->origin_snaps); 2366 err = snaplist_space(&pa->shared_snaps, 2367 snap->ds->ds_origin_txg, &pa->cloneusedsnap); 2368 if (err) 2369 return (err); 2370 2371 err = snaplist_space(&pa->clone_snaps, 2372 snap->ds->ds_origin_txg, &space); 2373 if (err) 2374 return (err); 2375 pa->cloneusedsnap += space; 2376 } 2377 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2378 err = snaplist_space(&pa->origin_snaps, 2379 origin_ds->ds_phys->ds_creation_txg, &pa->originusedsnap); 2380 if (err) 2381 return (err); 2382 } 2383 2384 return (0); 2385 } 2386 2387 static void 2388 dsl_dataset_promote_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2389 { 2390 dsl_dataset_t *hds = arg1; 2391 struct promotearg *pa = arg2; 2392 struct promotenode *snap = list_head(&pa->shared_snaps); 2393 dsl_dataset_t *origin_ds = snap->ds; 2394 dsl_dataset_t *origin_head; 2395 dsl_dir_t *dd = hds->ds_dir; 2396 dsl_pool_t *dp = hds->ds_dir->dd_pool; 2397 dsl_dir_t *odd = NULL; 2398 uint64_t oldnext_obj; 2399 int64_t delta; 2400 2401 ASSERT(0 == (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE)); 2402 2403 snap = list_head(&pa->origin_snaps); 2404 origin_head = snap->ds; 2405 2406 /* 2407 * We need to explicitly open odd, since origin_ds's dd will be 2408 * changing. 2409 */ 2410 VERIFY(0 == dsl_dir_open_obj(dp, origin_ds->ds_dir->dd_object, 2411 NULL, FTAG, &odd)); 2412 2413 /* change origin's next snap */ 2414 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2415 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2416 snap = list_tail(&pa->clone_snaps); 2417 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2418 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2419 2420 /* change the origin's next clone */ 2421 if (origin_ds->ds_phys->ds_next_clones_obj) { 2422 VERIFY3U(0, ==, zap_remove_int(dp->dp_meta_objset, 2423 origin_ds->ds_phys->ds_next_clones_obj, 2424 origin_ds->ds_phys->ds_next_snap_obj, tx)); 2425 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset, 2426 origin_ds->ds_phys->ds_next_clones_obj, 2427 oldnext_obj, tx)); 2428 } 2429 2430 /* change origin */ 2431 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2432 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2433 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2434 hds->ds_origin_txg = origin_head->ds_origin_txg; 2435 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2436 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2437 origin_head->ds_origin_txg = origin_ds->ds_phys->ds_creation_txg; 2438 2439 /* move snapshots to this dir */ 2440 for (snap = list_head(&pa->shared_snaps); snap; 2441 snap = list_next(&pa->shared_snaps, snap)) { 2442 dsl_dataset_t *ds = snap->ds; 2443 2444 /* unregister props as dsl_dir is changing */ 2445 if (ds->ds_user_ptr) { 2446 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 2447 ds->ds_user_ptr = NULL; 2448 } 2449 /* move snap name entry */ 2450 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2451 VERIFY(0 == dsl_dataset_snap_remove(origin_head, 2452 ds->ds_snapname, tx)); 2453 VERIFY(0 == zap_add(dp->dp_meta_objset, 2454 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2455 8, 1, &ds->ds_object, tx)); 2456 /* change containing dsl_dir */ 2457 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2458 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2459 ds->ds_phys->ds_dir_obj = dd->dd_object; 2460 ASSERT3P(ds->ds_dir, ==, odd); 2461 dsl_dir_close(ds->ds_dir, ds); 2462 VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object, 2463 NULL, ds, &ds->ds_dir)); 2464 2465 ASSERT3U(dsl_prop_numcb(ds), ==, 0); 2466 } 2467 2468 /* 2469 * Change space accounting. 2470 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2471 * both be valid, or both be 0 (resulting in delta == 0). This 2472 * is true for each of {clone,origin} independently. 2473 */ 2474 2475 delta = pa->cloneusedsnap - 2476 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2477 ASSERT3S(delta, >=, 0); 2478 ASSERT3U(pa->used, >=, delta); 2479 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2480 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2481 pa->used - delta, pa->comp, pa->uncomp, tx); 2482 2483 delta = pa->originusedsnap - 2484 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2485 ASSERT3S(delta, <=, 0); 2486 ASSERT3U(pa->used, >=, -delta); 2487 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2488 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2489 -pa->used - delta, -pa->comp, -pa->uncomp, tx); 2490 2491 origin_ds->ds_phys->ds_unique_bytes = pa->unique; 2492 2493 /* log history record */ 2494 spa_history_internal_log(LOG_DS_PROMOTE, dd->dd_pool->dp_spa, tx, 2495 cr, "dataset = %llu", hds->ds_object); 2496 2497 dsl_dir_close(odd, FTAG); 2498 } 2499 2500 static char *snaplist_tag = "snaplist"; 2501 /* 2502 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2503 * (exclusive) and last_obj (inclusive). The list will be in reverse 2504 * order (last_obj will be the list_head()). If first_obj == 0, do all 2505 * snapshots back to this dataset's origin. 2506 */ 2507 static int 2508 snaplist_make(dsl_pool_t *dp, boolean_t own, 2509 uint64_t first_obj, uint64_t last_obj, list_t *l) 2510 { 2511 uint64_t obj = last_obj; 2512 2513 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock)); 2514 2515 list_create(l, sizeof (struct promotenode), 2516 offsetof(struct promotenode, link)); 2517 2518 while (obj != first_obj) { 2519 dsl_dataset_t *ds; 2520 struct promotenode *snap; 2521 int err; 2522 2523 if (own) { 2524 err = dsl_dataset_own_obj(dp, obj, 2525 0, snaplist_tag, &ds); 2526 if (err == 0) 2527 dsl_dataset_make_exclusive(ds, snaplist_tag); 2528 } else { 2529 err = dsl_dataset_hold_obj(dp, obj, snaplist_tag, &ds); 2530 } 2531 if (err == ENOENT) { 2532 /* lost race with snapshot destroy */ 2533 struct promotenode *last = list_tail(l); 2534 ASSERT(obj != last->ds->ds_phys->ds_prev_snap_obj); 2535 obj = last->ds->ds_phys->ds_prev_snap_obj; 2536 continue; 2537 } else if (err) { 2538 return (err); 2539 } 2540 2541 if (first_obj == 0) 2542 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2543 2544 snap = kmem_alloc(sizeof (struct promotenode), KM_SLEEP); 2545 snap->ds = ds; 2546 list_insert_tail(l, snap); 2547 obj = ds->ds_phys->ds_prev_snap_obj; 2548 } 2549 2550 return (0); 2551 } 2552 2553 static int 2554 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2555 { 2556 struct promotenode *snap; 2557 2558 *spacep = 0; 2559 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2560 uint64_t used; 2561 int err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2562 mintxg, UINT64_MAX, &used); 2563 if (err) 2564 return (err); 2565 *spacep += used; 2566 } 2567 return (0); 2568 } 2569 2570 static void 2571 snaplist_destroy(list_t *l, boolean_t own) 2572 { 2573 struct promotenode *snap; 2574 2575 if (!list_link_active(&l->list_head)) 2576 return; 2577 2578 while ((snap = list_tail(l)) != NULL) { 2579 list_remove(l, snap); 2580 if (own) 2581 dsl_dataset_disown(snap->ds, snaplist_tag); 2582 else 2583 dsl_dataset_rele(snap->ds, snaplist_tag); 2584 kmem_free(snap, sizeof (struct promotenode)); 2585 } 2586 list_destroy(l); 2587 } 2588 2589 /* 2590 * Promote a clone. Nomenclature note: 2591 * "clone" or "cds": the original clone which is being promoted 2592 * "origin" or "ods": the snapshot which is originally clone's origin 2593 * "origin head" or "ohds": the dataset which is the head 2594 * (filesystem/volume) for the origin 2595 * "origin origin": the origin of the origin's filesystem (typically 2596 * NULL, indicating that the clone is not a clone of a clone). 2597 */ 2598 int 2599 dsl_dataset_promote(const char *name) 2600 { 2601 dsl_dataset_t *ds; 2602 dsl_dir_t *dd; 2603 dsl_pool_t *dp; 2604 dmu_object_info_t doi; 2605 struct promotearg pa = { 0 }; 2606 struct promotenode *snap; 2607 int err; 2608 2609 err = dsl_dataset_hold(name, FTAG, &ds); 2610 if (err) 2611 return (err); 2612 dd = ds->ds_dir; 2613 dp = dd->dd_pool; 2614 2615 err = dmu_object_info(dp->dp_meta_objset, 2616 ds->ds_phys->ds_snapnames_zapobj, &doi); 2617 if (err) { 2618 dsl_dataset_rele(ds, FTAG); 2619 return (err); 2620 } 2621 2622 if (dsl_dataset_is_snapshot(ds) || dd->dd_phys->dd_origin_obj == 0) { 2623 dsl_dataset_rele(ds, FTAG); 2624 return (EINVAL); 2625 } 2626 2627 /* 2628 * We are going to inherit all the snapshots taken before our 2629 * origin (i.e., our new origin will be our parent's origin). 2630 * Take ownership of them so that we can rename them into our 2631 * namespace. 2632 */ 2633 rw_enter(&dp->dp_config_rwlock, RW_READER); 2634 2635 err = snaplist_make(dp, B_TRUE, 0, dd->dd_phys->dd_origin_obj, 2636 &pa.shared_snaps); 2637 if (err != 0) 2638 goto out; 2639 2640 err = snaplist_make(dp, B_FALSE, 0, ds->ds_object, &pa.clone_snaps); 2641 if (err != 0) 2642 goto out; 2643 2644 snap = list_head(&pa.shared_snaps); 2645 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2646 err = snaplist_make(dp, B_FALSE, dd->dd_phys->dd_origin_obj, 2647 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, &pa.origin_snaps); 2648 if (err != 0) 2649 goto out; 2650 2651 if (dsl_dir_is_clone(snap->ds->ds_dir)) { 2652 err = dsl_dataset_own_obj(dp, 2653 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2654 0, FTAG, &pa.origin_origin); 2655 if (err != 0) 2656 goto out; 2657 } 2658 2659 out: 2660 rw_exit(&dp->dp_config_rwlock); 2661 2662 /* 2663 * Add in 128x the snapnames zapobj size, since we will be moving 2664 * a bunch of snapnames to the promoted ds, and dirtying their 2665 * bonus buffers. 2666 */ 2667 if (err == 0) { 2668 err = dsl_sync_task_do(dp, dsl_dataset_promote_check, 2669 dsl_dataset_promote_sync, ds, &pa, 2670 2 + 2 * doi.doi_physical_blks); 2671 } 2672 2673 snaplist_destroy(&pa.shared_snaps, B_TRUE); 2674 snaplist_destroy(&pa.clone_snaps, B_FALSE); 2675 snaplist_destroy(&pa.origin_snaps, B_FALSE); 2676 if (pa.origin_origin) 2677 dsl_dataset_disown(pa.origin_origin, FTAG); 2678 dsl_dataset_rele(ds, FTAG); 2679 return (err); 2680 } 2681 2682 struct cloneswaparg { 2683 dsl_dataset_t *cds; /* clone dataset */ 2684 dsl_dataset_t *ohds; /* origin's head dataset */ 2685 boolean_t force; 2686 int64_t unused_refres_delta; /* change in unconsumed refreservation */ 2687 }; 2688 2689 /* ARGSUSED */ 2690 static int 2691 dsl_dataset_clone_swap_check(void *arg1, void *arg2, dmu_tx_t *tx) 2692 { 2693 struct cloneswaparg *csa = arg1; 2694 2695 /* they should both be heads */ 2696 if (dsl_dataset_is_snapshot(csa->cds) || 2697 dsl_dataset_is_snapshot(csa->ohds)) 2698 return (EINVAL); 2699 2700 /* the branch point should be just before them */ 2701 if (csa->cds->ds_prev != csa->ohds->ds_prev) 2702 return (EINVAL); 2703 2704 /* cds should be the clone */ 2705 if (csa->cds->ds_prev->ds_phys->ds_next_snap_obj != 2706 csa->ohds->ds_object) 2707 return (EINVAL); 2708 2709 /* the clone should be a child of the origin */ 2710 if (csa->cds->ds_dir->dd_parent != csa->ohds->ds_dir) 2711 return (EINVAL); 2712 2713 /* ohds shouldn't be modified unless 'force' */ 2714 if (!csa->force && dsl_dataset_modified_since_lastsnap(csa->ohds)) 2715 return (ETXTBSY); 2716 2717 /* adjust amount of any unconsumed refreservation */ 2718 csa->unused_refres_delta = 2719 (int64_t)MIN(csa->ohds->ds_reserved, 2720 csa->ohds->ds_phys->ds_unique_bytes) - 2721 (int64_t)MIN(csa->ohds->ds_reserved, 2722 csa->cds->ds_phys->ds_unique_bytes); 2723 2724 if (csa->unused_refres_delta > 0 && 2725 csa->unused_refres_delta > 2726 dsl_dir_space_available(csa->ohds->ds_dir, NULL, 0, TRUE)) 2727 return (ENOSPC); 2728 2729 return (0); 2730 } 2731 2732 /* ARGSUSED */ 2733 static void 2734 dsl_dataset_clone_swap_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2735 { 2736 struct cloneswaparg *csa = arg1; 2737 dsl_pool_t *dp = csa->cds->ds_dir->dd_pool; 2738 2739 ASSERT(csa->cds->ds_reserved == 0); 2740 ASSERT(csa->cds->ds_quota == csa->ohds->ds_quota); 2741 2742 dmu_buf_will_dirty(csa->cds->ds_dbuf, tx); 2743 dmu_buf_will_dirty(csa->ohds->ds_dbuf, tx); 2744 dmu_buf_will_dirty(csa->cds->ds_prev->ds_dbuf, tx); 2745 2746 if (csa->cds->ds_user_ptr != NULL) { 2747 csa->cds->ds_user_evict_func(csa->cds, csa->cds->ds_user_ptr); 2748 csa->cds->ds_user_ptr = NULL; 2749 } 2750 2751 if (csa->ohds->ds_user_ptr != NULL) { 2752 csa->ohds->ds_user_evict_func(csa->ohds, 2753 csa->ohds->ds_user_ptr); 2754 csa->ohds->ds_user_ptr = NULL; 2755 } 2756 2757 /* reset origin's unique bytes */ 2758 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2759 csa->cds->ds_prev->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2760 &csa->cds->ds_prev->ds_phys->ds_unique_bytes)); 2761 2762 /* swap blkptrs */ 2763 { 2764 blkptr_t tmp; 2765 tmp = csa->ohds->ds_phys->ds_bp; 2766 csa->ohds->ds_phys->ds_bp = csa->cds->ds_phys->ds_bp; 2767 csa->cds->ds_phys->ds_bp = tmp; 2768 } 2769 2770 /* set dd_*_bytes */ 2771 { 2772 int64_t dused, dcomp, duncomp; 2773 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2774 uint64_t odl_used, odl_comp, odl_uncomp; 2775 2776 ASSERT3U(csa->cds->ds_dir->dd_phys-> 2777 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2778 2779 VERIFY(0 == bplist_space(&csa->cds->ds_deadlist, &cdl_used, 2780 &cdl_comp, &cdl_uncomp)); 2781 VERIFY(0 == bplist_space(&csa->ohds->ds_deadlist, &odl_used, 2782 &odl_comp, &odl_uncomp)); 2783 2784 dused = csa->cds->ds_phys->ds_used_bytes + cdl_used - 2785 (csa->ohds->ds_phys->ds_used_bytes + odl_used); 2786 dcomp = csa->cds->ds_phys->ds_compressed_bytes + cdl_comp - 2787 (csa->ohds->ds_phys->ds_compressed_bytes + odl_comp); 2788 duncomp = csa->cds->ds_phys->ds_uncompressed_bytes + 2789 cdl_uncomp - 2790 (csa->ohds->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2791 2792 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_HEAD, 2793 dused, dcomp, duncomp, tx); 2794 dsl_dir_diduse_space(csa->cds->ds_dir, DD_USED_HEAD, 2795 -dused, -dcomp, -duncomp, tx); 2796 2797 /* 2798 * The difference in the space used by snapshots is the 2799 * difference in snapshot space due to the head's 2800 * deadlist (since that's the only thing that's 2801 * changing that affects the snapused). 2802 */ 2803 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2804 csa->ohds->ds_origin_txg, UINT64_MAX, &cdl_used)); 2805 VERIFY(0 == bplist_space_birthrange(&csa->ohds->ds_deadlist, 2806 csa->ohds->ds_origin_txg, UINT64_MAX, &odl_used)); 2807 dsl_dir_transfer_space(csa->ohds->ds_dir, cdl_used - odl_used, 2808 DD_USED_HEAD, DD_USED_SNAP, tx); 2809 } 2810 2811 #define SWITCH64(x, y) \ 2812 { \ 2813 uint64_t __tmp = (x); \ 2814 (x) = (y); \ 2815 (y) = __tmp; \ 2816 } 2817 2818 /* swap ds_*_bytes */ 2819 SWITCH64(csa->ohds->ds_phys->ds_used_bytes, 2820 csa->cds->ds_phys->ds_used_bytes); 2821 SWITCH64(csa->ohds->ds_phys->ds_compressed_bytes, 2822 csa->cds->ds_phys->ds_compressed_bytes); 2823 SWITCH64(csa->ohds->ds_phys->ds_uncompressed_bytes, 2824 csa->cds->ds_phys->ds_uncompressed_bytes); 2825 SWITCH64(csa->ohds->ds_phys->ds_unique_bytes, 2826 csa->cds->ds_phys->ds_unique_bytes); 2827 2828 /* apply any parent delta for change in unconsumed refreservation */ 2829 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_REFRSRV, 2830 csa->unused_refres_delta, 0, 0, tx); 2831 2832 /* swap deadlists */ 2833 bplist_close(&csa->cds->ds_deadlist); 2834 bplist_close(&csa->ohds->ds_deadlist); 2835 SWITCH64(csa->ohds->ds_phys->ds_deadlist_obj, 2836 csa->cds->ds_phys->ds_deadlist_obj); 2837 VERIFY(0 == bplist_open(&csa->cds->ds_deadlist, dp->dp_meta_objset, 2838 csa->cds->ds_phys->ds_deadlist_obj)); 2839 VERIFY(0 == bplist_open(&csa->ohds->ds_deadlist, dp->dp_meta_objset, 2840 csa->ohds->ds_phys->ds_deadlist_obj)); 2841 2842 dsl_pool_ds_clone_swapped(csa->ohds, csa->cds, tx); 2843 } 2844 2845 /* 2846 * Swap 'clone' with its origin head file system. Used at the end 2847 * of "online recv" to swizzle the file system to the new version. 2848 */ 2849 int 2850 dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head, 2851 boolean_t force) 2852 { 2853 struct cloneswaparg csa; 2854 int error; 2855 2856 ASSERT(clone->ds_owner); 2857 ASSERT(origin_head->ds_owner); 2858 retry: 2859 /* Need exclusive access for the swap */ 2860 rw_enter(&clone->ds_rwlock, RW_WRITER); 2861 if (!rw_tryenter(&origin_head->ds_rwlock, RW_WRITER)) { 2862 rw_exit(&clone->ds_rwlock); 2863 rw_enter(&origin_head->ds_rwlock, RW_WRITER); 2864 if (!rw_tryenter(&clone->ds_rwlock, RW_WRITER)) { 2865 rw_exit(&origin_head->ds_rwlock); 2866 goto retry; 2867 } 2868 } 2869 csa.cds = clone; 2870 csa.ohds = origin_head; 2871 csa.force = force; 2872 error = dsl_sync_task_do(clone->ds_dir->dd_pool, 2873 dsl_dataset_clone_swap_check, 2874 dsl_dataset_clone_swap_sync, &csa, NULL, 9); 2875 return (error); 2876 } 2877 2878 /* 2879 * Given a pool name and a dataset object number in that pool, 2880 * return the name of that dataset. 2881 */ 2882 int 2883 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2884 { 2885 spa_t *spa; 2886 dsl_pool_t *dp; 2887 dsl_dataset_t *ds; 2888 int error; 2889 2890 if ((error = spa_open(pname, &spa, FTAG)) != 0) 2891 return (error); 2892 dp = spa_get_dsl(spa); 2893 rw_enter(&dp->dp_config_rwlock, RW_READER); 2894 if ((error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds)) == 0) { 2895 dsl_dataset_name(ds, buf); 2896 dsl_dataset_rele(ds, FTAG); 2897 } 2898 rw_exit(&dp->dp_config_rwlock); 2899 spa_close(spa, FTAG); 2900 2901 return (error); 2902 } 2903 2904 int 2905 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2906 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2907 { 2908 int error = 0; 2909 2910 ASSERT3S(asize, >, 0); 2911 2912 /* 2913 * *ref_rsrv is the portion of asize that will come from any 2914 * unconsumed refreservation space. 2915 */ 2916 *ref_rsrv = 0; 2917 2918 mutex_enter(&ds->ds_lock); 2919 /* 2920 * Make a space adjustment for reserved bytes. 2921 */ 2922 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2923 ASSERT3U(*used, >=, 2924 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2925 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2926 *ref_rsrv = 2927 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2928 } 2929 2930 if (!check_quota || ds->ds_quota == 0) { 2931 mutex_exit(&ds->ds_lock); 2932 return (0); 2933 } 2934 /* 2935 * If they are requesting more space, and our current estimate 2936 * is over quota, they get to try again unless the actual 2937 * on-disk is over quota and there are no pending changes (which 2938 * may free up space for us). 2939 */ 2940 if (ds->ds_phys->ds_used_bytes + inflight >= ds->ds_quota) { 2941 if (inflight > 0 || ds->ds_phys->ds_used_bytes < ds->ds_quota) 2942 error = ERESTART; 2943 else 2944 error = EDQUOT; 2945 } 2946 mutex_exit(&ds->ds_lock); 2947 2948 return (error); 2949 } 2950 2951 /* ARGSUSED */ 2952 static int 2953 dsl_dataset_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx) 2954 { 2955 dsl_dataset_t *ds = arg1; 2956 uint64_t *quotap = arg2; 2957 uint64_t new_quota = *quotap; 2958 2959 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_REFQUOTA) 2960 return (ENOTSUP); 2961 2962 if (new_quota == 0) 2963 return (0); 2964 2965 if (new_quota < ds->ds_phys->ds_used_bytes || 2966 new_quota < ds->ds_reserved) 2967 return (ENOSPC); 2968 2969 return (0); 2970 } 2971 2972 /* ARGSUSED */ 2973 void 2974 dsl_dataset_set_quota_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2975 { 2976 dsl_dataset_t *ds = arg1; 2977 uint64_t *quotap = arg2; 2978 uint64_t new_quota = *quotap; 2979 2980 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2981 2982 ds->ds_quota = new_quota; 2983 2984 dsl_prop_set_uint64_sync(ds->ds_dir, "refquota", new_quota, cr, tx); 2985 2986 spa_history_internal_log(LOG_DS_REFQUOTA, ds->ds_dir->dd_pool->dp_spa, 2987 tx, cr, "%lld dataset = %llu ", 2988 (longlong_t)new_quota, ds->ds_object); 2989 } 2990 2991 int 2992 dsl_dataset_set_quota(const char *dsname, uint64_t quota) 2993 { 2994 dsl_dataset_t *ds; 2995 int err; 2996 2997 err = dsl_dataset_hold(dsname, FTAG, &ds); 2998 if (err) 2999 return (err); 3000 3001 if (quota != ds->ds_quota) { 3002 /* 3003 * If someone removes a file, then tries to set the quota, we 3004 * want to make sure the file freeing takes effect. 3005 */ 3006 txg_wait_open(ds->ds_dir->dd_pool, 0); 3007 3008 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3009 dsl_dataset_set_quota_check, dsl_dataset_set_quota_sync, 3010 ds, "a, 0); 3011 } 3012 dsl_dataset_rele(ds, FTAG); 3013 return (err); 3014 } 3015 3016 static int 3017 dsl_dataset_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx) 3018 { 3019 dsl_dataset_t *ds = arg1; 3020 uint64_t *reservationp = arg2; 3021 uint64_t new_reservation = *reservationp; 3022 int64_t delta; 3023 uint64_t unique; 3024 3025 if (new_reservation > INT64_MAX) 3026 return (EOVERFLOW); 3027 3028 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < 3029 SPA_VERSION_REFRESERVATION) 3030 return (ENOTSUP); 3031 3032 if (dsl_dataset_is_snapshot(ds)) 3033 return (EINVAL); 3034 3035 /* 3036 * If we are doing the preliminary check in open context, the 3037 * space estimates may be inaccurate. 3038 */ 3039 if (!dmu_tx_is_syncing(tx)) 3040 return (0); 3041 3042 mutex_enter(&ds->ds_lock); 3043 unique = dsl_dataset_unique(ds); 3044 delta = MAX(unique, new_reservation) - MAX(unique, ds->ds_reserved); 3045 mutex_exit(&ds->ds_lock); 3046 3047 if (delta > 0 && 3048 delta > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 3049 return (ENOSPC); 3050 if (delta > 0 && ds->ds_quota > 0 && 3051 new_reservation > ds->ds_quota) 3052 return (ENOSPC); 3053 3054 return (0); 3055 } 3056 3057 /* ARGSUSED */ 3058 static void 3059 dsl_dataset_set_reservation_sync(void *arg1, void *arg2, cred_t *cr, 3060 dmu_tx_t *tx) 3061 { 3062 dsl_dataset_t *ds = arg1; 3063 uint64_t *reservationp = arg2; 3064 uint64_t new_reservation = *reservationp; 3065 uint64_t unique; 3066 int64_t delta; 3067 3068 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3069 3070 mutex_enter(&ds->ds_dir->dd_lock); 3071 mutex_enter(&ds->ds_lock); 3072 unique = dsl_dataset_unique(ds); 3073 delta = MAX(0, (int64_t)(new_reservation - unique)) - 3074 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3075 ds->ds_reserved = new_reservation; 3076 mutex_exit(&ds->ds_lock); 3077 3078 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3079 mutex_exit(&ds->ds_dir->dd_lock); 3080 dsl_prop_set_uint64_sync(ds->ds_dir, "refreservation", 3081 new_reservation, cr, tx); 3082 3083 spa_history_internal_log(LOG_DS_REFRESERV, 3084 ds->ds_dir->dd_pool->dp_spa, tx, cr, "%lld dataset = %llu", 3085 (longlong_t)new_reservation, ds->ds_object); 3086 } 3087 3088 int 3089 dsl_dataset_set_reservation(const char *dsname, uint64_t reservation) 3090 { 3091 dsl_dataset_t *ds; 3092 int err; 3093 3094 err = dsl_dataset_hold(dsname, FTAG, &ds); 3095 if (err) 3096 return (err); 3097 3098 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3099 dsl_dataset_set_reservation_check, 3100 dsl_dataset_set_reservation_sync, ds, &reservation, 0); 3101 dsl_dataset_rele(ds, FTAG); 3102 return (err); 3103 } 3104