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 2009 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 *dsp = NULL; 552 return (EBUSY); 553 } 554 return (0); 555 } 556 557 int 558 dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp) 559 { 560 dsl_dir_t *dd; 561 dsl_pool_t *dp; 562 const char *snapname; 563 uint64_t obj; 564 int err = 0; 565 566 err = dsl_dir_open_spa(NULL, name, FTAG, &dd, &snapname); 567 if (err) 568 return (err); 569 570 dp = dd->dd_pool; 571 obj = dd->dd_phys->dd_head_dataset_obj; 572 rw_enter(&dp->dp_config_rwlock, RW_READER); 573 if (obj) 574 err = dsl_dataset_get_ref(dp, obj, tag, dsp); 575 else 576 err = ENOENT; 577 if (err) 578 goto out; 579 580 err = dsl_dataset_hold_ref(*dsp, tag); 581 582 /* we may be looking for a snapshot */ 583 if (err == 0 && snapname != NULL) { 584 dsl_dataset_t *ds = NULL; 585 586 if (*snapname++ != '@') { 587 dsl_dataset_rele(*dsp, tag); 588 err = ENOENT; 589 goto out; 590 } 591 592 dprintf("looking for snapshot '%s'\n", snapname); 593 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 594 if (err == 0) 595 err = dsl_dataset_get_ref(dp, obj, tag, &ds); 596 dsl_dataset_rele(*dsp, tag); 597 598 ASSERT3U((err == 0), ==, (ds != NULL)); 599 600 if (ds) { 601 mutex_enter(&ds->ds_lock); 602 if (ds->ds_snapname[0] == 0) 603 (void) strlcpy(ds->ds_snapname, snapname, 604 sizeof (ds->ds_snapname)); 605 mutex_exit(&ds->ds_lock); 606 err = dsl_dataset_hold_ref(ds, tag); 607 *dsp = err ? NULL : ds; 608 } 609 } 610 out: 611 rw_exit(&dp->dp_config_rwlock); 612 dsl_dir_close(dd, FTAG); 613 return (err); 614 } 615 616 int 617 dsl_dataset_own(const char *name, int flags, void *owner, dsl_dataset_t **dsp) 618 { 619 int err = dsl_dataset_hold(name, owner, dsp); 620 if (err) 621 return (err); 622 if ((*dsp)->ds_phys->ds_num_children > 0 && 623 !DS_MODE_IS_READONLY(flags)) { 624 dsl_dataset_rele(*dsp, owner); 625 return (EROFS); 626 } 627 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 628 dsl_dataset_rele(*dsp, owner); 629 return (EBUSY); 630 } 631 return (0); 632 } 633 634 void 635 dsl_dataset_name(dsl_dataset_t *ds, char *name) 636 { 637 if (ds == NULL) { 638 (void) strcpy(name, "mos"); 639 } else { 640 dsl_dir_name(ds->ds_dir, name); 641 VERIFY(0 == dsl_dataset_get_snapname(ds)); 642 if (ds->ds_snapname[0]) { 643 (void) strcat(name, "@"); 644 /* 645 * We use a "recursive" mutex so that we 646 * can call dprintf_ds() with ds_lock held. 647 */ 648 if (!MUTEX_HELD(&ds->ds_lock)) { 649 mutex_enter(&ds->ds_lock); 650 (void) strcat(name, ds->ds_snapname); 651 mutex_exit(&ds->ds_lock); 652 } else { 653 (void) strcat(name, ds->ds_snapname); 654 } 655 } 656 } 657 } 658 659 static int 660 dsl_dataset_namelen(dsl_dataset_t *ds) 661 { 662 int result; 663 664 if (ds == NULL) { 665 result = 3; /* "mos" */ 666 } else { 667 result = dsl_dir_namelen(ds->ds_dir); 668 VERIFY(0 == dsl_dataset_get_snapname(ds)); 669 if (ds->ds_snapname[0]) { 670 ++result; /* adding one for the @-sign */ 671 if (!MUTEX_HELD(&ds->ds_lock)) { 672 mutex_enter(&ds->ds_lock); 673 result += strlen(ds->ds_snapname); 674 mutex_exit(&ds->ds_lock); 675 } else { 676 result += strlen(ds->ds_snapname); 677 } 678 } 679 } 680 681 return (result); 682 } 683 684 void 685 dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag) 686 { 687 dmu_buf_rele(ds->ds_dbuf, tag); 688 } 689 690 void 691 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 692 { 693 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) { 694 rw_exit(&ds->ds_rwlock); 695 } 696 dsl_dataset_drop_ref(ds, tag); 697 } 698 699 void 700 dsl_dataset_disown(dsl_dataset_t *ds, void *owner) 701 { 702 ASSERT((ds->ds_owner == owner && ds->ds_dbuf) || 703 (DSL_DATASET_IS_DESTROYED(ds) && ds->ds_dbuf == NULL)); 704 705 mutex_enter(&ds->ds_lock); 706 ds->ds_owner = NULL; 707 if (RW_WRITE_HELD(&ds->ds_rwlock)) { 708 rw_exit(&ds->ds_rwlock); 709 cv_broadcast(&ds->ds_exclusive_cv); 710 } 711 mutex_exit(&ds->ds_lock); 712 if (ds->ds_dbuf) 713 dsl_dataset_drop_ref(ds, owner); 714 else 715 dsl_dataset_evict(ds->ds_dbuf, ds); 716 } 717 718 boolean_t 719 dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok, void *owner) 720 { 721 boolean_t gotit = FALSE; 722 723 mutex_enter(&ds->ds_lock); 724 if (ds->ds_owner == NULL && 725 (!DS_IS_INCONSISTENT(ds) || inconsistentok)) { 726 ds->ds_owner = owner; 727 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) 728 rw_exit(&ds->ds_rwlock); 729 gotit = TRUE; 730 } 731 mutex_exit(&ds->ds_lock); 732 return (gotit); 733 } 734 735 void 736 dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *owner) 737 { 738 ASSERT3P(owner, ==, ds->ds_owner); 739 if (!RW_WRITE_HELD(&ds->ds_rwlock)) 740 rw_enter(&ds->ds_rwlock, RW_WRITER); 741 } 742 743 uint64_t 744 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 745 uint64_t flags, dmu_tx_t *tx) 746 { 747 dsl_pool_t *dp = dd->dd_pool; 748 dmu_buf_t *dbuf; 749 dsl_dataset_phys_t *dsphys; 750 uint64_t dsobj; 751 objset_t *mos = dp->dp_meta_objset; 752 753 if (origin == NULL) 754 origin = dp->dp_origin_snap; 755 756 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 757 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 758 ASSERT(dmu_tx_is_syncing(tx)); 759 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 760 761 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 762 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 763 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 764 dmu_buf_will_dirty(dbuf, tx); 765 dsphys = dbuf->db_data; 766 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 767 dsphys->ds_dir_obj = dd->dd_object; 768 dsphys->ds_flags = flags; 769 dsphys->ds_fsid_guid = unique_create(); 770 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 771 sizeof (dsphys->ds_guid)); 772 dsphys->ds_snapnames_zapobj = 773 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 774 DMU_OT_NONE, 0, tx); 775 dsphys->ds_creation_time = gethrestime_sec(); 776 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 777 dsphys->ds_deadlist_obj = 778 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 779 780 if (origin) { 781 dsphys->ds_prev_snap_obj = origin->ds_object; 782 dsphys->ds_prev_snap_txg = 783 origin->ds_phys->ds_creation_txg; 784 dsphys->ds_used_bytes = 785 origin->ds_phys->ds_used_bytes; 786 dsphys->ds_compressed_bytes = 787 origin->ds_phys->ds_compressed_bytes; 788 dsphys->ds_uncompressed_bytes = 789 origin->ds_phys->ds_uncompressed_bytes; 790 dsphys->ds_bp = origin->ds_phys->ds_bp; 791 dsphys->ds_flags |= origin->ds_phys->ds_flags; 792 793 dmu_buf_will_dirty(origin->ds_dbuf, tx); 794 origin->ds_phys->ds_num_children++; 795 796 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 797 if (origin->ds_phys->ds_next_clones_obj == 0) { 798 origin->ds_phys->ds_next_clones_obj = 799 zap_create(mos, 800 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 801 } 802 VERIFY(0 == zap_add_int(mos, 803 origin->ds_phys->ds_next_clones_obj, 804 dsobj, tx)); 805 } 806 807 dmu_buf_will_dirty(dd->dd_dbuf, tx); 808 dd->dd_phys->dd_origin_obj = origin->ds_object; 809 } 810 811 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 812 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 813 814 dmu_buf_rele(dbuf, FTAG); 815 816 dmu_buf_will_dirty(dd->dd_dbuf, tx); 817 dd->dd_phys->dd_head_dataset_obj = dsobj; 818 819 return (dsobj); 820 } 821 822 uint64_t 823 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 824 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 825 { 826 dsl_pool_t *dp = pdd->dd_pool; 827 uint64_t dsobj, ddobj; 828 dsl_dir_t *dd; 829 830 ASSERT(lastname[0] != '@'); 831 832 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 833 VERIFY(0 == dsl_dir_open_obj(dp, ddobj, lastname, FTAG, &dd)); 834 835 dsobj = dsl_dataset_create_sync_dd(dd, origin, flags, tx); 836 837 dsl_deleg_set_create_perms(dd, tx, cr); 838 839 dsl_dir_close(dd, FTAG); 840 841 return (dsobj); 842 } 843 844 struct destroyarg { 845 dsl_sync_task_group_t *dstg; 846 char *snapname; 847 char *failed; 848 }; 849 850 static int 851 dsl_snapshot_destroy_one(char *name, void *arg) 852 { 853 struct destroyarg *da = arg; 854 dsl_dataset_t *ds; 855 char *cp; 856 int err; 857 858 (void) strcat(name, "@"); 859 (void) strcat(name, da->snapname); 860 err = dsl_dataset_own(name, DS_MODE_READONLY | DS_MODE_INCONSISTENT, 861 da->dstg, &ds); 862 cp = strchr(name, '@'); 863 *cp = '\0'; 864 if (err == 0) { 865 dsl_dataset_make_exclusive(ds, da->dstg); 866 if (ds->ds_user_ptr) { 867 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 868 ds->ds_user_ptr = NULL; 869 } 870 dsl_sync_task_create(da->dstg, dsl_dataset_destroy_check, 871 dsl_dataset_destroy_sync, ds, da->dstg, 0); 872 } else if (err == ENOENT) { 873 err = 0; 874 } else { 875 (void) strcpy(da->failed, name); 876 } 877 return (err); 878 } 879 880 /* 881 * Destroy 'snapname' in all descendants of 'fsname'. 882 */ 883 #pragma weak dmu_snapshots_destroy = dsl_snapshots_destroy 884 int 885 dsl_snapshots_destroy(char *fsname, char *snapname) 886 { 887 int err; 888 struct destroyarg da; 889 dsl_sync_task_t *dst; 890 spa_t *spa; 891 892 err = spa_open(fsname, &spa, FTAG); 893 if (err) 894 return (err); 895 da.dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 896 da.snapname = snapname; 897 da.failed = fsname; 898 899 err = dmu_objset_find(fsname, 900 dsl_snapshot_destroy_one, &da, DS_FIND_CHILDREN); 901 902 if (err == 0) 903 err = dsl_sync_task_group_wait(da.dstg); 904 905 for (dst = list_head(&da.dstg->dstg_tasks); dst; 906 dst = list_next(&da.dstg->dstg_tasks, dst)) { 907 dsl_dataset_t *ds = dst->dst_arg1; 908 /* 909 * Return the file system name that triggered the error 910 */ 911 if (dst->dst_err) { 912 dsl_dataset_name(ds, fsname); 913 *strchr(fsname, '@') = '\0'; 914 } 915 dsl_dataset_disown(ds, da.dstg); 916 } 917 918 dsl_sync_task_group_destroy(da.dstg); 919 spa_close(spa, FTAG); 920 return (err); 921 } 922 923 /* 924 * ds must be opened as OWNER. On return (whether successful or not), 925 * ds will be closed and caller can no longer dereference it. 926 */ 927 int 928 dsl_dataset_destroy(dsl_dataset_t *ds, void *tag) 929 { 930 int err; 931 dsl_sync_task_group_t *dstg; 932 objset_t *os; 933 dsl_dir_t *dd; 934 uint64_t obj; 935 936 if (dsl_dataset_is_snapshot(ds)) { 937 /* Destroying a snapshot is simpler */ 938 dsl_dataset_make_exclusive(ds, tag); 939 940 if (ds->ds_user_ptr) { 941 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 942 ds->ds_user_ptr = NULL; 943 } 944 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 945 dsl_dataset_destroy_check, dsl_dataset_destroy_sync, 946 ds, tag, 0); 947 goto out; 948 } 949 950 dd = ds->ds_dir; 951 952 /* 953 * Check for errors and mark this ds as inconsistent, in 954 * case we crash while freeing the objects. 955 */ 956 err = dsl_sync_task_do(dd->dd_pool, dsl_dataset_destroy_begin_check, 957 dsl_dataset_destroy_begin_sync, ds, NULL, 0); 958 if (err) 959 goto out; 960 961 err = dmu_objset_open_ds(ds, DMU_OST_ANY, &os); 962 if (err) 963 goto out; 964 965 /* 966 * remove the objects in open context, so that we won't 967 * have too much to do in syncing context. 968 */ 969 for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 970 ds->ds_phys->ds_prev_snap_txg)) { 971 /* 972 * Ignore errors, if there is not enough disk space 973 * we will deal with it in dsl_dataset_destroy_sync(). 974 */ 975 (void) dmu_free_object(os, obj); 976 } 977 978 /* 979 * We need to sync out all in-flight IO before we try to evict 980 * (the dataset evict func is trying to clear the cached entries 981 * for this dataset in the ARC). 982 */ 983 txg_wait_synced(dd->dd_pool, 0); 984 985 /* 986 * If we managed to free all the objects in open 987 * context, the user space accounting should be zero. 988 */ 989 if (ds->ds_phys->ds_bp.blk_fill == 0 && 990 dmu_objset_userused_enabled(os->os)) { 991 uint64_t count; 992 993 ASSERT(zap_count(os, DMU_USERUSED_OBJECT, &count) != 0 || 994 count == 0); 995 ASSERT(zap_count(os, DMU_GROUPUSED_OBJECT, &count) != 0 || 996 count == 0); 997 } 998 999 dmu_objset_close(os); 1000 if (err != ESRCH) 1001 goto out; 1002 1003 rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER); 1004 err = dsl_dir_open_obj(dd->dd_pool, dd->dd_object, NULL, FTAG, &dd); 1005 rw_exit(&dd->dd_pool->dp_config_rwlock); 1006 1007 if (err) 1008 goto out; 1009 1010 if (ds->ds_user_ptr) { 1011 /* 1012 * We need to sync out all in-flight IO before we try 1013 * to evict (the dataset evict func is trying to clear 1014 * the cached entries for this dataset in the ARC). 1015 */ 1016 txg_wait_synced(dd->dd_pool, 0); 1017 } 1018 1019 /* 1020 * Blow away the dsl_dir + head dataset. 1021 */ 1022 dsl_dataset_make_exclusive(ds, tag); 1023 if (ds->ds_user_ptr) { 1024 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1025 ds->ds_user_ptr = NULL; 1026 } 1027 dstg = dsl_sync_task_group_create(ds->ds_dir->dd_pool); 1028 dsl_sync_task_create(dstg, dsl_dataset_destroy_check, 1029 dsl_dataset_destroy_sync, ds, tag, 0); 1030 dsl_sync_task_create(dstg, dsl_dir_destroy_check, 1031 dsl_dir_destroy_sync, dd, FTAG, 0); 1032 err = dsl_sync_task_group_wait(dstg); 1033 dsl_sync_task_group_destroy(dstg); 1034 /* if it is successful, dsl_dir_destroy_sync will close the dd */ 1035 if (err) 1036 dsl_dir_close(dd, FTAG); 1037 out: 1038 dsl_dataset_disown(ds, tag); 1039 return (err); 1040 } 1041 1042 int 1043 dsl_dataset_rollback(dsl_dataset_t *ds, dmu_objset_type_t ost) 1044 { 1045 int err; 1046 1047 ASSERT(ds->ds_owner); 1048 1049 dsl_dataset_make_exclusive(ds, ds->ds_owner); 1050 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 1051 dsl_dataset_rollback_check, dsl_dataset_rollback_sync, 1052 ds, &ost, 0); 1053 /* drop exclusive access */ 1054 mutex_enter(&ds->ds_lock); 1055 rw_exit(&ds->ds_rwlock); 1056 cv_broadcast(&ds->ds_exclusive_cv); 1057 mutex_exit(&ds->ds_lock); 1058 return (err); 1059 } 1060 1061 void * 1062 dsl_dataset_set_user_ptr(dsl_dataset_t *ds, 1063 void *p, dsl_dataset_evict_func_t func) 1064 { 1065 void *old; 1066 1067 mutex_enter(&ds->ds_lock); 1068 old = ds->ds_user_ptr; 1069 if (old == NULL) { 1070 ds->ds_user_ptr = p; 1071 ds->ds_user_evict_func = func; 1072 } 1073 mutex_exit(&ds->ds_lock); 1074 return (old); 1075 } 1076 1077 void * 1078 dsl_dataset_get_user_ptr(dsl_dataset_t *ds) 1079 { 1080 return (ds->ds_user_ptr); 1081 } 1082 1083 blkptr_t * 1084 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1085 { 1086 return (&ds->ds_phys->ds_bp); 1087 } 1088 1089 void 1090 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1091 { 1092 ASSERT(dmu_tx_is_syncing(tx)); 1093 /* If it's the meta-objset, set dp_meta_rootbp */ 1094 if (ds == NULL) { 1095 tx->tx_pool->dp_meta_rootbp = *bp; 1096 } else { 1097 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1098 ds->ds_phys->ds_bp = *bp; 1099 } 1100 } 1101 1102 spa_t * 1103 dsl_dataset_get_spa(dsl_dataset_t *ds) 1104 { 1105 return (ds->ds_dir->dd_pool->dp_spa); 1106 } 1107 1108 void 1109 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1110 { 1111 dsl_pool_t *dp; 1112 1113 if (ds == NULL) /* this is the meta-objset */ 1114 return; 1115 1116 ASSERT(ds->ds_user_ptr != NULL); 1117 1118 if (ds->ds_phys->ds_next_snap_obj != 0) 1119 panic("dirtying snapshot!"); 1120 1121 dp = ds->ds_dir->dd_pool; 1122 1123 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg) == 0) { 1124 /* up the hold count until we can be written out */ 1125 dmu_buf_add_ref(ds->ds_dbuf, ds); 1126 } 1127 } 1128 1129 /* 1130 * The unique space in the head dataset can be calculated by subtracting 1131 * the space used in the most recent snapshot, that is still being used 1132 * in this file system, from the space currently in use. To figure out 1133 * the space in the most recent snapshot still in use, we need to take 1134 * the total space used in the snapshot and subtract out the space that 1135 * has been freed up since the snapshot was taken. 1136 */ 1137 static void 1138 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 1139 { 1140 uint64_t mrs_used; 1141 uint64_t dlused, dlcomp, dluncomp; 1142 1143 ASSERT(ds->ds_object == ds->ds_dir->dd_phys->dd_head_dataset_obj); 1144 1145 if (ds->ds_phys->ds_prev_snap_obj != 0) 1146 mrs_used = ds->ds_prev->ds_phys->ds_used_bytes; 1147 else 1148 mrs_used = 0; 1149 1150 VERIFY(0 == bplist_space(&ds->ds_deadlist, &dlused, &dlcomp, 1151 &dluncomp)); 1152 1153 ASSERT3U(dlused, <=, mrs_used); 1154 ds->ds_phys->ds_unique_bytes = 1155 ds->ds_phys->ds_used_bytes - (mrs_used - dlused); 1156 1157 if (!DS_UNIQUE_IS_ACCURATE(ds) && 1158 spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1159 SPA_VERSION_UNIQUE_ACCURATE) 1160 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1161 } 1162 1163 static uint64_t 1164 dsl_dataset_unique(dsl_dataset_t *ds) 1165 { 1166 if (!DS_UNIQUE_IS_ACCURATE(ds) && !dsl_dataset_is_snapshot(ds)) 1167 dsl_dataset_recalc_head_uniq(ds); 1168 1169 return (ds->ds_phys->ds_unique_bytes); 1170 } 1171 1172 struct killarg { 1173 dsl_dataset_t *ds; 1174 zio_t *zio; 1175 dmu_tx_t *tx; 1176 }; 1177 1178 /* ARGSUSED */ 1179 static int 1180 kill_blkptr(spa_t *spa, blkptr_t *bp, const zbookmark_t *zb, 1181 const dnode_phys_t *dnp, void *arg) 1182 { 1183 struct killarg *ka = arg; 1184 1185 if (bp == NULL) 1186 return (0); 1187 1188 if ((zb->zb_level == -1ULL && zb->zb_blkid != 0) || 1189 (zb->zb_object != 0 && dnp == NULL)) { 1190 /* 1191 * It's a block in the intent log. It has no 1192 * accounting, so just free it. 1193 */ 1194 VERIFY3U(0, ==, dsl_free(ka->zio, ka->tx->tx_pool, 1195 ka->tx->tx_txg, bp, NULL, NULL, ARC_NOWAIT)); 1196 } else { 1197 ASSERT3U(bp->blk_birth, >, ka->ds->ds_phys->ds_prev_snap_txg); 1198 (void) dsl_dataset_block_kill(ka->ds, bp, ka->zio, ka->tx); 1199 } 1200 1201 return (0); 1202 } 1203 1204 /* ARGSUSED */ 1205 static int 1206 dsl_dataset_rollback_check(void *arg1, void *arg2, dmu_tx_t *tx) 1207 { 1208 dsl_dataset_t *ds = arg1; 1209 dmu_objset_type_t *ost = arg2; 1210 1211 /* 1212 * We can only roll back to emptyness if it is a ZPL objset. 1213 */ 1214 if (*ost != DMU_OST_ZFS && ds->ds_phys->ds_prev_snap_txg == 0) 1215 return (EINVAL); 1216 1217 /* 1218 * This must not be a snapshot. 1219 */ 1220 if (ds->ds_phys->ds_next_snap_obj != 0) 1221 return (EINVAL); 1222 1223 /* 1224 * If we made changes this txg, traverse_dataset won't find 1225 * them. Try again. 1226 */ 1227 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1228 return (EAGAIN); 1229 1230 return (0); 1231 } 1232 1233 /* ARGSUSED */ 1234 static void 1235 dsl_dataset_rollback_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1236 { 1237 dsl_dataset_t *ds = arg1; 1238 dmu_objset_type_t *ost = arg2; 1239 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1240 1241 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1242 1243 if (ds->ds_user_ptr != NULL) { 1244 /* 1245 * We need to make sure that the objset_impl_t is reopened after 1246 * we do the rollback, otherwise it will have the wrong 1247 * objset_phys_t. Normally this would happen when this 1248 * dataset-open is closed, thus causing the 1249 * dataset to be immediately evicted. But when doing "zfs recv 1250 * -F", we reopen the objset before that, so that there is no 1251 * window where the dataset is closed and inconsistent. 1252 */ 1253 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1254 ds->ds_user_ptr = NULL; 1255 } 1256 1257 /* Transfer space that was freed since last snap back to the head. */ 1258 { 1259 uint64_t used; 1260 1261 VERIFY(0 == bplist_space_birthrange(&ds->ds_deadlist, 1262 ds->ds_origin_txg, UINT64_MAX, &used)); 1263 dsl_dir_transfer_space(ds->ds_dir, used, 1264 DD_USED_SNAP, DD_USED_HEAD, tx); 1265 } 1266 1267 /* Zero out the deadlist. */ 1268 bplist_close(&ds->ds_deadlist); 1269 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1270 ds->ds_phys->ds_deadlist_obj = 1271 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1272 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1273 ds->ds_phys->ds_deadlist_obj)); 1274 1275 { 1276 /* 1277 * Free blkptrs that we gave birth to - this covers 1278 * claimed but not played log blocks too. 1279 */ 1280 zio_t *zio; 1281 struct killarg ka; 1282 1283 zio = zio_root(tx->tx_pool->dp_spa, NULL, NULL, 1284 ZIO_FLAG_MUSTSUCCEED); 1285 ka.ds = ds; 1286 ka.zio = zio; 1287 ka.tx = tx; 1288 (void) traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1289 TRAVERSE_POST, kill_blkptr, &ka); 1290 (void) zio_wait(zio); 1291 } 1292 1293 ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || ds->ds_phys->ds_unique_bytes == 0); 1294 1295 if (ds->ds_prev && ds->ds_prev != ds->ds_dir->dd_pool->dp_origin_snap) { 1296 /* Change our contents to that of the prev snapshot */ 1297 1298 ASSERT3U(ds->ds_prev->ds_object, ==, 1299 ds->ds_phys->ds_prev_snap_obj); 1300 ASSERT3U(ds->ds_phys->ds_used_bytes, <=, 1301 ds->ds_prev->ds_phys->ds_used_bytes); 1302 1303 ds->ds_phys->ds_bp = ds->ds_prev->ds_phys->ds_bp; 1304 ds->ds_phys->ds_used_bytes = 1305 ds->ds_prev->ds_phys->ds_used_bytes; 1306 ds->ds_phys->ds_compressed_bytes = 1307 ds->ds_prev->ds_phys->ds_compressed_bytes; 1308 ds->ds_phys->ds_uncompressed_bytes = 1309 ds->ds_prev->ds_phys->ds_uncompressed_bytes; 1310 ds->ds_phys->ds_flags = ds->ds_prev->ds_phys->ds_flags; 1311 1312 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1313 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1314 ds->ds_prev->ds_phys->ds_unique_bytes = 0; 1315 } 1316 } else { 1317 objset_impl_t *osi; 1318 1319 ASSERT3U(ds->ds_phys->ds_used_bytes, ==, 0); 1320 ASSERT3U(ds->ds_phys->ds_compressed_bytes, ==, 0); 1321 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, ==, 0); 1322 1323 bzero(&ds->ds_phys->ds_bp, sizeof (blkptr_t)); 1324 ds->ds_phys->ds_flags = 0; 1325 ds->ds_phys->ds_unique_bytes = 0; 1326 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1327 SPA_VERSION_UNIQUE_ACCURATE) 1328 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1329 1330 osi = dmu_objset_create_impl(ds->ds_dir->dd_pool->dp_spa, ds, 1331 &ds->ds_phys->ds_bp, *ost, tx); 1332 #ifdef _KERNEL 1333 zfs_create_fs(&osi->os, kcred, NULL, tx); 1334 #endif 1335 } 1336 1337 spa_history_internal_log(LOG_DS_ROLLBACK, ds->ds_dir->dd_pool->dp_spa, 1338 tx, cr, "dataset = %llu", ds->ds_object); 1339 } 1340 1341 /* ARGSUSED */ 1342 static int 1343 dsl_dataset_destroy_begin_check(void *arg1, void *arg2, dmu_tx_t *tx) 1344 { 1345 dsl_dataset_t *ds = arg1; 1346 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1347 uint64_t count; 1348 int err; 1349 1350 /* 1351 * Can't delete a head dataset if there are snapshots of it. 1352 * (Except if the only snapshots are from the branch we cloned 1353 * from.) 1354 */ 1355 if (ds->ds_prev != NULL && 1356 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1357 return (EINVAL); 1358 1359 /* 1360 * This is really a dsl_dir thing, but check it here so that 1361 * we'll be less likely to leave this dataset inconsistent & 1362 * nearly destroyed. 1363 */ 1364 err = zap_count(mos, ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count); 1365 if (err) 1366 return (err); 1367 if (count != 0) 1368 return (EEXIST); 1369 1370 return (0); 1371 } 1372 1373 /* ARGSUSED */ 1374 static void 1375 dsl_dataset_destroy_begin_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1376 { 1377 dsl_dataset_t *ds = arg1; 1378 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1379 1380 /* Mark it as inconsistent on-disk, in case we crash */ 1381 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1382 ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT; 1383 1384 spa_history_internal_log(LOG_DS_DESTROY_BEGIN, dp->dp_spa, tx, 1385 cr, "dataset = %llu", ds->ds_object); 1386 } 1387 1388 /* ARGSUSED */ 1389 int 1390 dsl_dataset_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx) 1391 { 1392 dsl_dataset_t *ds = arg1; 1393 1394 /* we have an owner hold, so noone else can destroy us */ 1395 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 1396 1397 /* Can't delete a branch point. */ 1398 if (ds->ds_phys->ds_num_children > 1) 1399 return (EEXIST); 1400 1401 /* 1402 * Can't delete a head dataset if there are snapshots of it. 1403 * (Except if the only snapshots are from the branch we cloned 1404 * from.) 1405 */ 1406 if (ds->ds_prev != NULL && 1407 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1408 return (EINVAL); 1409 1410 /* 1411 * If we made changes this txg, traverse_dsl_dataset won't find 1412 * them. Try again. 1413 */ 1414 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1415 return (EAGAIN); 1416 1417 /* XXX we should do some i/o error checking... */ 1418 return (0); 1419 } 1420 1421 struct refsarg { 1422 kmutex_t lock; 1423 boolean_t gone; 1424 kcondvar_t cv; 1425 }; 1426 1427 /* ARGSUSED */ 1428 static void 1429 dsl_dataset_refs_gone(dmu_buf_t *db, void *argv) 1430 { 1431 struct refsarg *arg = argv; 1432 1433 mutex_enter(&arg->lock); 1434 arg->gone = TRUE; 1435 cv_signal(&arg->cv); 1436 mutex_exit(&arg->lock); 1437 } 1438 1439 static void 1440 dsl_dataset_drain_refs(dsl_dataset_t *ds, void *tag) 1441 { 1442 struct refsarg arg; 1443 1444 mutex_init(&arg.lock, NULL, MUTEX_DEFAULT, NULL); 1445 cv_init(&arg.cv, NULL, CV_DEFAULT, NULL); 1446 arg.gone = FALSE; 1447 (void) dmu_buf_update_user(ds->ds_dbuf, ds, &arg, &ds->ds_phys, 1448 dsl_dataset_refs_gone); 1449 dmu_buf_rele(ds->ds_dbuf, tag); 1450 mutex_enter(&arg.lock); 1451 while (!arg.gone) 1452 cv_wait(&arg.cv, &arg.lock); 1453 ASSERT(arg.gone); 1454 mutex_exit(&arg.lock); 1455 ds->ds_dbuf = NULL; 1456 ds->ds_phys = NULL; 1457 mutex_destroy(&arg.lock); 1458 cv_destroy(&arg.cv); 1459 } 1460 1461 void 1462 dsl_dataset_destroy_sync(void *arg1, void *tag, cred_t *cr, dmu_tx_t *tx) 1463 { 1464 dsl_dataset_t *ds = arg1; 1465 zio_t *zio; 1466 int err; 1467 int after_branch_point = FALSE; 1468 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1469 objset_t *mos = dp->dp_meta_objset; 1470 dsl_dataset_t *ds_prev = NULL; 1471 uint64_t obj; 1472 1473 ASSERT(ds->ds_owner); 1474 ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); 1475 ASSERT(ds->ds_prev == NULL || 1476 ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object); 1477 ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); 1478 1479 /* signal any waiters that this dataset is going away */ 1480 mutex_enter(&ds->ds_lock); 1481 ds->ds_owner = dsl_reaper; 1482 cv_broadcast(&ds->ds_exclusive_cv); 1483 mutex_exit(&ds->ds_lock); 1484 1485 /* Remove our reservation */ 1486 if (ds->ds_reserved != 0) { 1487 uint64_t val = 0; 1488 dsl_dataset_set_reservation_sync(ds, &val, cr, tx); 1489 ASSERT3U(ds->ds_reserved, ==, 0); 1490 } 1491 1492 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1493 1494 dsl_pool_ds_destroyed(ds, tx); 1495 1496 obj = ds->ds_object; 1497 1498 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1499 if (ds->ds_prev) { 1500 ds_prev = ds->ds_prev; 1501 } else { 1502 VERIFY(0 == dsl_dataset_hold_obj(dp, 1503 ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev)); 1504 } 1505 after_branch_point = 1506 (ds_prev->ds_phys->ds_next_snap_obj != obj); 1507 1508 dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); 1509 if (after_branch_point && 1510 ds_prev->ds_phys->ds_next_clones_obj != 0) { 1511 VERIFY3U(0, ==, zap_remove_int(mos, 1512 ds_prev->ds_phys->ds_next_clones_obj, obj, tx)); 1513 if (ds->ds_phys->ds_next_snap_obj != 0) { 1514 VERIFY(0 == zap_add_int(mos, 1515 ds_prev->ds_phys->ds_next_clones_obj, 1516 ds->ds_phys->ds_next_snap_obj, tx)); 1517 } 1518 } 1519 if (after_branch_point && 1520 ds->ds_phys->ds_next_snap_obj == 0) { 1521 /* This clone is toast. */ 1522 ASSERT(ds_prev->ds_phys->ds_num_children > 1); 1523 ds_prev->ds_phys->ds_num_children--; 1524 } else if (!after_branch_point) { 1525 ds_prev->ds_phys->ds_next_snap_obj = 1526 ds->ds_phys->ds_next_snap_obj; 1527 } 1528 } 1529 1530 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 1531 1532 if (ds->ds_phys->ds_next_snap_obj != 0) { 1533 blkptr_t bp; 1534 dsl_dataset_t *ds_next; 1535 uint64_t itor = 0; 1536 uint64_t old_unique; 1537 int64_t used = 0, compressed = 0, uncompressed = 0; 1538 1539 VERIFY(0 == dsl_dataset_hold_obj(dp, 1540 ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next)); 1541 ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj); 1542 1543 old_unique = dsl_dataset_unique(ds_next); 1544 1545 dmu_buf_will_dirty(ds_next->ds_dbuf, tx); 1546 ds_next->ds_phys->ds_prev_snap_obj = 1547 ds->ds_phys->ds_prev_snap_obj; 1548 ds_next->ds_phys->ds_prev_snap_txg = 1549 ds->ds_phys->ds_prev_snap_txg; 1550 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1551 ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0); 1552 1553 /* 1554 * Transfer to our deadlist (which will become next's 1555 * new deadlist) any entries from next's current 1556 * deadlist which were born before prev, and free the 1557 * other entries. 1558 * 1559 * XXX we're doing this long task with the config lock held 1560 */ 1561 while (bplist_iterate(&ds_next->ds_deadlist, &itor, &bp) == 0) { 1562 if (bp.blk_birth <= ds->ds_phys->ds_prev_snap_txg) { 1563 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, 1564 &bp, tx)); 1565 if (ds_prev && !after_branch_point && 1566 bp.blk_birth > 1567 ds_prev->ds_phys->ds_prev_snap_txg) { 1568 ds_prev->ds_phys->ds_unique_bytes += 1569 bp_get_dasize(dp->dp_spa, &bp); 1570 } 1571 } else { 1572 used += bp_get_dasize(dp->dp_spa, &bp); 1573 compressed += BP_GET_PSIZE(&bp); 1574 uncompressed += BP_GET_UCSIZE(&bp); 1575 /* XXX check return value? */ 1576 (void) dsl_free(zio, dp, tx->tx_txg, 1577 &bp, NULL, NULL, ARC_NOWAIT); 1578 } 1579 } 1580 1581 ASSERT3U(used, ==, ds->ds_phys->ds_unique_bytes); 1582 1583 /* change snapused */ 1584 dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP, 1585 -used, -compressed, -uncompressed, tx); 1586 1587 /* free next's deadlist */ 1588 bplist_close(&ds_next->ds_deadlist); 1589 bplist_destroy(mos, ds_next->ds_phys->ds_deadlist_obj, tx); 1590 1591 /* set next's deadlist to our deadlist */ 1592 bplist_close(&ds->ds_deadlist); 1593 ds_next->ds_phys->ds_deadlist_obj = 1594 ds->ds_phys->ds_deadlist_obj; 1595 VERIFY(0 == bplist_open(&ds_next->ds_deadlist, mos, 1596 ds_next->ds_phys->ds_deadlist_obj)); 1597 ds->ds_phys->ds_deadlist_obj = 0; 1598 1599 if (ds_next->ds_phys->ds_next_snap_obj != 0) { 1600 /* 1601 * Update next's unique to include blocks which 1602 * were previously shared by only this snapshot 1603 * and it. Those blocks will be born after the 1604 * prev snap and before this snap, and will have 1605 * died after the next snap and before the one 1606 * after that (ie. be on the snap after next's 1607 * deadlist). 1608 * 1609 * XXX we're doing this long task with the 1610 * config lock held 1611 */ 1612 dsl_dataset_t *ds_after_next; 1613 uint64_t space; 1614 1615 VERIFY(0 == dsl_dataset_hold_obj(dp, 1616 ds_next->ds_phys->ds_next_snap_obj, 1617 FTAG, &ds_after_next)); 1618 1619 VERIFY(0 == 1620 bplist_space_birthrange(&ds_after_next->ds_deadlist, 1621 ds->ds_phys->ds_prev_snap_txg, 1622 ds->ds_phys->ds_creation_txg, &space)); 1623 ds_next->ds_phys->ds_unique_bytes += space; 1624 1625 dsl_dataset_rele(ds_after_next, FTAG); 1626 ASSERT3P(ds_next->ds_prev, ==, NULL); 1627 } else { 1628 ASSERT3P(ds_next->ds_prev, ==, ds); 1629 dsl_dataset_drop_ref(ds_next->ds_prev, ds_next); 1630 ds_next->ds_prev = NULL; 1631 if (ds_prev) { 1632 VERIFY(0 == dsl_dataset_get_ref(dp, 1633 ds->ds_phys->ds_prev_snap_obj, 1634 ds_next, &ds_next->ds_prev)); 1635 } 1636 1637 dsl_dataset_recalc_head_uniq(ds_next); 1638 1639 /* 1640 * Reduce the amount of our unconsmed refreservation 1641 * being charged to our parent by the amount of 1642 * new unique data we have gained. 1643 */ 1644 if (old_unique < ds_next->ds_reserved) { 1645 int64_t mrsdelta; 1646 uint64_t new_unique = 1647 ds_next->ds_phys->ds_unique_bytes; 1648 1649 ASSERT(old_unique <= new_unique); 1650 mrsdelta = MIN(new_unique - old_unique, 1651 ds_next->ds_reserved - old_unique); 1652 dsl_dir_diduse_space(ds->ds_dir, 1653 DD_USED_REFRSRV, -mrsdelta, 0, 0, tx); 1654 } 1655 } 1656 dsl_dataset_rele(ds_next, FTAG); 1657 } else { 1658 /* 1659 * There's no next snapshot, so this is a head dataset. 1660 * Destroy the deadlist. Unless it's a clone, the 1661 * deadlist should be empty. (If it's a clone, it's 1662 * safe to ignore the deadlist contents.) 1663 */ 1664 struct killarg ka; 1665 1666 ASSERT(after_branch_point || bplist_empty(&ds->ds_deadlist)); 1667 bplist_close(&ds->ds_deadlist); 1668 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1669 ds->ds_phys->ds_deadlist_obj = 0; 1670 1671 /* 1672 * Free everything that we point to (that's born after 1673 * the previous snapshot, if we are a clone) 1674 * 1675 * NB: this should be very quick, because we already 1676 * freed all the objects in open context. 1677 */ 1678 ka.ds = ds; 1679 ka.zio = zio; 1680 ka.tx = tx; 1681 err = traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1682 TRAVERSE_POST, kill_blkptr, &ka); 1683 ASSERT3U(err, ==, 0); 1684 ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || 1685 ds->ds_phys->ds_unique_bytes == 0); 1686 } 1687 1688 err = zio_wait(zio); 1689 ASSERT3U(err, ==, 0); 1690 1691 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == ds->ds_object) { 1692 /* Erase the link in the dir */ 1693 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); 1694 ds->ds_dir->dd_phys->dd_head_dataset_obj = 0; 1695 ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0); 1696 err = zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx); 1697 ASSERT(err == 0); 1698 } else { 1699 /* remove from snapshot namespace */ 1700 dsl_dataset_t *ds_head; 1701 ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0); 1702 VERIFY(0 == dsl_dataset_hold_obj(dp, 1703 ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head)); 1704 VERIFY(0 == dsl_dataset_get_snapname(ds)); 1705 #ifdef ZFS_DEBUG 1706 { 1707 uint64_t val; 1708 1709 err = dsl_dataset_snap_lookup(ds_head, 1710 ds->ds_snapname, &val); 1711 ASSERT3U(err, ==, 0); 1712 ASSERT3U(val, ==, obj); 1713 } 1714 #endif 1715 err = dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx); 1716 ASSERT(err == 0); 1717 dsl_dataset_rele(ds_head, FTAG); 1718 } 1719 1720 if (ds_prev && ds->ds_prev != ds_prev) 1721 dsl_dataset_rele(ds_prev, FTAG); 1722 1723 spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); 1724 spa_history_internal_log(LOG_DS_DESTROY, dp->dp_spa, tx, 1725 cr, "dataset = %llu", ds->ds_object); 1726 1727 if (ds->ds_phys->ds_next_clones_obj != 0) { 1728 uint64_t count; 1729 ASSERT(0 == zap_count(mos, 1730 ds->ds_phys->ds_next_clones_obj, &count) && count == 0); 1731 VERIFY(0 == dmu_object_free(mos, 1732 ds->ds_phys->ds_next_clones_obj, tx)); 1733 } 1734 if (ds->ds_phys->ds_props_obj != 0) 1735 VERIFY(0 == zap_destroy(mos, ds->ds_phys->ds_props_obj, tx)); 1736 dsl_dir_close(ds->ds_dir, ds); 1737 ds->ds_dir = NULL; 1738 dsl_dataset_drain_refs(ds, tag); 1739 VERIFY(0 == dmu_object_free(mos, obj, tx)); 1740 } 1741 1742 static int 1743 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1744 { 1745 uint64_t asize; 1746 1747 if (!dmu_tx_is_syncing(tx)) 1748 return (0); 1749 1750 /* 1751 * If there's an fs-only reservation, any blocks that might become 1752 * owned by the snapshot dataset must be accommodated by space 1753 * outside of the reservation. 1754 */ 1755 asize = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1756 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, FALSE)) 1757 return (ENOSPC); 1758 1759 /* 1760 * Propogate any reserved space for this snapshot to other 1761 * snapshot checks in this sync group. 1762 */ 1763 if (asize > 0) 1764 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1765 1766 return (0); 1767 } 1768 1769 /* ARGSUSED */ 1770 int 1771 dsl_dataset_snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx) 1772 { 1773 dsl_dataset_t *ds = arg1; 1774 const char *snapname = arg2; 1775 int err; 1776 uint64_t value; 1777 1778 /* 1779 * We don't allow multiple snapshots of the same txg. If there 1780 * is already one, try again. 1781 */ 1782 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 1783 return (EAGAIN); 1784 1785 /* 1786 * Check for conflicting name snapshot name. 1787 */ 1788 err = dsl_dataset_snap_lookup(ds, snapname, &value); 1789 if (err == 0) 1790 return (EEXIST); 1791 if (err != ENOENT) 1792 return (err); 1793 1794 /* 1795 * Check that the dataset's name is not too long. Name consists 1796 * of the dataset's length + 1 for the @-sign + snapshot name's length 1797 */ 1798 if (dsl_dataset_namelen(ds) + 1 + strlen(snapname) >= MAXNAMELEN) 1799 return (ENAMETOOLONG); 1800 1801 err = dsl_dataset_snapshot_reserve_space(ds, tx); 1802 if (err) 1803 return (err); 1804 1805 ds->ds_trysnap_txg = tx->tx_txg; 1806 return (0); 1807 } 1808 1809 void 1810 dsl_dataset_snapshot_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1811 { 1812 dsl_dataset_t *ds = arg1; 1813 const char *snapname = arg2; 1814 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1815 dmu_buf_t *dbuf; 1816 dsl_dataset_phys_t *dsphys; 1817 uint64_t dsobj, crtxg; 1818 objset_t *mos = dp->dp_meta_objset; 1819 int err; 1820 1821 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1822 1823 /* 1824 * The origin's ds_creation_txg has to be < TXG_INITIAL 1825 */ 1826 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1827 crtxg = 1; 1828 else 1829 crtxg = tx->tx_txg; 1830 1831 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1832 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1833 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1834 dmu_buf_will_dirty(dbuf, tx); 1835 dsphys = dbuf->db_data; 1836 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1837 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1838 dsphys->ds_fsid_guid = unique_create(); 1839 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1840 sizeof (dsphys->ds_guid)); 1841 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1842 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1843 dsphys->ds_next_snap_obj = ds->ds_object; 1844 dsphys->ds_num_children = 1; 1845 dsphys->ds_creation_time = gethrestime_sec(); 1846 dsphys->ds_creation_txg = crtxg; 1847 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1848 dsphys->ds_used_bytes = ds->ds_phys->ds_used_bytes; 1849 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1850 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1851 dsphys->ds_flags = ds->ds_phys->ds_flags; 1852 dsphys->ds_bp = ds->ds_phys->ds_bp; 1853 dmu_buf_rele(dbuf, FTAG); 1854 1855 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1856 if (ds->ds_prev) { 1857 uint64_t next_clones_obj = 1858 ds->ds_prev->ds_phys->ds_next_clones_obj; 1859 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1860 ds->ds_object || 1861 ds->ds_prev->ds_phys->ds_num_children > 1); 1862 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1863 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1864 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1865 ds->ds_prev->ds_phys->ds_creation_txg); 1866 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1867 } else if (next_clones_obj != 0) { 1868 VERIFY3U(0, ==, zap_remove_int(mos, 1869 next_clones_obj, dsphys->ds_next_snap_obj, tx)); 1870 VERIFY3U(0, ==, zap_add_int(mos, 1871 next_clones_obj, dsobj, tx)); 1872 } 1873 } 1874 1875 /* 1876 * If we have a reference-reservation on this dataset, we will 1877 * need to increase the amount of refreservation being charged 1878 * since our unique space is going to zero. 1879 */ 1880 if (ds->ds_reserved) { 1881 int64_t add = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1882 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1883 add, 0, 0, tx); 1884 } 1885 1886 bplist_close(&ds->ds_deadlist); 1887 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1888 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1889 ds->ds_phys->ds_prev_snap_obj = dsobj; 1890 ds->ds_phys->ds_prev_snap_txg = crtxg; 1891 ds->ds_phys->ds_unique_bytes = 0; 1892 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1893 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1894 ds->ds_phys->ds_deadlist_obj = 1895 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1896 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1897 ds->ds_phys->ds_deadlist_obj)); 1898 1899 dprintf("snap '%s' -> obj %llu\n", snapname, dsobj); 1900 err = zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1901 snapname, 8, 1, &dsobj, tx); 1902 ASSERT(err == 0); 1903 1904 if (ds->ds_prev) 1905 dsl_dataset_drop_ref(ds->ds_prev, ds); 1906 VERIFY(0 == dsl_dataset_get_ref(dp, 1907 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1908 1909 dsl_pool_ds_snapshotted(ds, tx); 1910 1911 spa_history_internal_log(LOG_DS_SNAPSHOT, dp->dp_spa, tx, cr, 1912 "dataset = %llu", dsobj); 1913 } 1914 1915 void 1916 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1917 { 1918 ASSERT(dmu_tx_is_syncing(tx)); 1919 ASSERT(ds->ds_user_ptr != NULL); 1920 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1921 1922 /* 1923 * in case we had to change ds_fsid_guid when we opened it, 1924 * sync it out now. 1925 */ 1926 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1927 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1928 1929 dsl_dir_dirty(ds->ds_dir, tx); 1930 dmu_objset_sync(ds->ds_user_ptr, zio, tx); 1931 } 1932 1933 void 1934 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1935 { 1936 uint64_t refd, avail, uobjs, aobjs; 1937 1938 dsl_dir_stats(ds->ds_dir, nv); 1939 1940 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1941 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1942 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1943 1944 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1945 ds->ds_phys->ds_creation_time); 1946 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1947 ds->ds_phys->ds_creation_txg); 1948 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1949 ds->ds_quota); 1950 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1951 ds->ds_reserved); 1952 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1953 ds->ds_phys->ds_guid); 1954 1955 if (ds->ds_phys->ds_next_snap_obj) { 1956 /* 1957 * This is a snapshot; override the dd's space used with 1958 * our unique space and compression ratio. 1959 */ 1960 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1961 ds->ds_phys->ds_unique_bytes); 1962 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, 1963 ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1964 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1965 ds->ds_phys->ds_compressed_bytes)); 1966 } 1967 } 1968 1969 void 1970 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1971 { 1972 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1973 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1974 stat->dds_guid = ds->ds_phys->ds_guid; 1975 if (ds->ds_phys->ds_next_snap_obj) { 1976 stat->dds_is_snapshot = B_TRUE; 1977 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1978 } else { 1979 stat->dds_is_snapshot = B_FALSE; 1980 stat->dds_num_clones = 0; 1981 } 1982 1983 /* clone origin is really a dsl_dir thing... */ 1984 rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER); 1985 if (dsl_dir_is_clone(ds->ds_dir)) { 1986 dsl_dataset_t *ods; 1987 1988 VERIFY(0 == dsl_dataset_get_ref(ds->ds_dir->dd_pool, 1989 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1990 dsl_dataset_name(ods, stat->dds_origin); 1991 dsl_dataset_drop_ref(ods, FTAG); 1992 } else { 1993 stat->dds_origin[0] = '\0'; 1994 } 1995 rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock); 1996 } 1997 1998 uint64_t 1999 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 2000 { 2001 return (ds->ds_fsid_guid); 2002 } 2003 2004 void 2005 dsl_dataset_space(dsl_dataset_t *ds, 2006 uint64_t *refdbytesp, uint64_t *availbytesp, 2007 uint64_t *usedobjsp, uint64_t *availobjsp) 2008 { 2009 *refdbytesp = ds->ds_phys->ds_used_bytes; 2010 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 2011 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 2012 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 2013 if (ds->ds_quota != 0) { 2014 /* 2015 * Adjust available bytes according to refquota 2016 */ 2017 if (*refdbytesp < ds->ds_quota) 2018 *availbytesp = MIN(*availbytesp, 2019 ds->ds_quota - *refdbytesp); 2020 else 2021 *availbytesp = 0; 2022 } 2023 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 2024 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 2025 } 2026 2027 boolean_t 2028 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds) 2029 { 2030 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2031 2032 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 2033 dsl_pool_sync_context(dp)); 2034 if (ds->ds_prev == NULL) 2035 return (B_FALSE); 2036 if (ds->ds_phys->ds_bp.blk_birth > 2037 ds->ds_prev->ds_phys->ds_creation_txg) 2038 return (B_TRUE); 2039 return (B_FALSE); 2040 } 2041 2042 /* ARGSUSED */ 2043 static int 2044 dsl_dataset_snapshot_rename_check(void *arg1, void *arg2, dmu_tx_t *tx) 2045 { 2046 dsl_dataset_t *ds = arg1; 2047 char *newsnapname = arg2; 2048 dsl_dir_t *dd = ds->ds_dir; 2049 dsl_dataset_t *hds; 2050 uint64_t val; 2051 int err; 2052 2053 err = dsl_dataset_hold_obj(dd->dd_pool, 2054 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds); 2055 if (err) 2056 return (err); 2057 2058 /* new name better not be in use */ 2059 err = dsl_dataset_snap_lookup(hds, newsnapname, &val); 2060 dsl_dataset_rele(hds, FTAG); 2061 2062 if (err == 0) 2063 err = EEXIST; 2064 else if (err == ENOENT) 2065 err = 0; 2066 2067 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2068 if (dsl_dir_namelen(ds->ds_dir) + 1 + strlen(newsnapname) >= MAXNAMELEN) 2069 err = ENAMETOOLONG; 2070 2071 return (err); 2072 } 2073 2074 static void 2075 dsl_dataset_snapshot_rename_sync(void *arg1, void *arg2, 2076 cred_t *cr, dmu_tx_t *tx) 2077 { 2078 dsl_dataset_t *ds = arg1; 2079 const char *newsnapname = arg2; 2080 dsl_dir_t *dd = ds->ds_dir; 2081 objset_t *mos = dd->dd_pool->dp_meta_objset; 2082 dsl_dataset_t *hds; 2083 int err; 2084 2085 ASSERT(ds->ds_phys->ds_next_snap_obj != 0); 2086 2087 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, 2088 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds)); 2089 2090 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2091 err = dsl_dataset_snap_remove(hds, ds->ds_snapname, tx); 2092 ASSERT3U(err, ==, 0); 2093 mutex_enter(&ds->ds_lock); 2094 (void) strcpy(ds->ds_snapname, newsnapname); 2095 mutex_exit(&ds->ds_lock); 2096 err = zap_add(mos, hds->ds_phys->ds_snapnames_zapobj, 2097 ds->ds_snapname, 8, 1, &ds->ds_object, tx); 2098 ASSERT3U(err, ==, 0); 2099 2100 spa_history_internal_log(LOG_DS_RENAME, dd->dd_pool->dp_spa, tx, 2101 cr, "dataset = %llu", ds->ds_object); 2102 dsl_dataset_rele(hds, FTAG); 2103 } 2104 2105 struct renamesnaparg { 2106 dsl_sync_task_group_t *dstg; 2107 char failed[MAXPATHLEN]; 2108 char *oldsnap; 2109 char *newsnap; 2110 }; 2111 2112 static int 2113 dsl_snapshot_rename_one(char *name, void *arg) 2114 { 2115 struct renamesnaparg *ra = arg; 2116 dsl_dataset_t *ds = NULL; 2117 char *cp; 2118 int err; 2119 2120 cp = name + strlen(name); 2121 *cp = '@'; 2122 (void) strcpy(cp + 1, ra->oldsnap); 2123 2124 /* 2125 * For recursive snapshot renames the parent won't be changing 2126 * so we just pass name for both the to/from argument. 2127 */ 2128 err = zfs_secpolicy_rename_perms(name, name, CRED()); 2129 if (err == ENOENT) { 2130 return (0); 2131 } else if (err) { 2132 (void) strcpy(ra->failed, name); 2133 return (err); 2134 } 2135 2136 #ifdef _KERNEL 2137 /* 2138 * For all filesystems undergoing rename, we'll need to unmount it. 2139 */ 2140 (void) zfs_unmount_snap(name, NULL); 2141 #endif 2142 err = dsl_dataset_hold(name, ra->dstg, &ds); 2143 *cp = '\0'; 2144 if (err == ENOENT) { 2145 return (0); 2146 } else if (err) { 2147 (void) strcpy(ra->failed, name); 2148 return (err); 2149 } 2150 2151 dsl_sync_task_create(ra->dstg, dsl_dataset_snapshot_rename_check, 2152 dsl_dataset_snapshot_rename_sync, ds, ra->newsnap, 0); 2153 2154 return (0); 2155 } 2156 2157 static int 2158 dsl_recursive_rename(char *oldname, const char *newname) 2159 { 2160 int err; 2161 struct renamesnaparg *ra; 2162 dsl_sync_task_t *dst; 2163 spa_t *spa; 2164 char *cp, *fsname = spa_strdup(oldname); 2165 int len = strlen(oldname); 2166 2167 /* truncate the snapshot name to get the fsname */ 2168 cp = strchr(fsname, '@'); 2169 *cp = '\0'; 2170 2171 err = spa_open(fsname, &spa, FTAG); 2172 if (err) { 2173 kmem_free(fsname, len + 1); 2174 return (err); 2175 } 2176 ra = kmem_alloc(sizeof (struct renamesnaparg), KM_SLEEP); 2177 ra->dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 2178 2179 ra->oldsnap = strchr(oldname, '@') + 1; 2180 ra->newsnap = strchr(newname, '@') + 1; 2181 *ra->failed = '\0'; 2182 2183 err = dmu_objset_find(fsname, dsl_snapshot_rename_one, ra, 2184 DS_FIND_CHILDREN); 2185 kmem_free(fsname, len + 1); 2186 2187 if (err == 0) { 2188 err = dsl_sync_task_group_wait(ra->dstg); 2189 } 2190 2191 for (dst = list_head(&ra->dstg->dstg_tasks); dst; 2192 dst = list_next(&ra->dstg->dstg_tasks, dst)) { 2193 dsl_dataset_t *ds = dst->dst_arg1; 2194 if (dst->dst_err) { 2195 dsl_dir_name(ds->ds_dir, ra->failed); 2196 (void) strcat(ra->failed, "@"); 2197 (void) strcat(ra->failed, ra->newsnap); 2198 } 2199 dsl_dataset_rele(ds, ra->dstg); 2200 } 2201 2202 if (err) 2203 (void) strcpy(oldname, ra->failed); 2204 2205 dsl_sync_task_group_destroy(ra->dstg); 2206 kmem_free(ra, sizeof (struct renamesnaparg)); 2207 spa_close(spa, FTAG); 2208 return (err); 2209 } 2210 2211 static int 2212 dsl_valid_rename(char *oldname, void *arg) 2213 { 2214 int delta = *(int *)arg; 2215 2216 if (strlen(oldname) + delta >= MAXNAMELEN) 2217 return (ENAMETOOLONG); 2218 2219 return (0); 2220 } 2221 2222 #pragma weak dmu_objset_rename = dsl_dataset_rename 2223 int 2224 dsl_dataset_rename(char *oldname, const char *newname, boolean_t recursive) 2225 { 2226 dsl_dir_t *dd; 2227 dsl_dataset_t *ds; 2228 const char *tail; 2229 int err; 2230 2231 err = dsl_dir_open(oldname, FTAG, &dd, &tail); 2232 if (err) 2233 return (err); 2234 /* 2235 * If there are more than 2 references there may be holds 2236 * hanging around that haven't been cleared out yet. 2237 */ 2238 if (dmu_buf_refcount(dd->dd_dbuf) > 2) 2239 txg_wait_synced(dd->dd_pool, 0); 2240 if (tail == NULL) { 2241 int delta = strlen(newname) - strlen(oldname); 2242 2243 /* if we're growing, validate child name lengths */ 2244 if (delta > 0) 2245 err = dmu_objset_find(oldname, dsl_valid_rename, 2246 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS); 2247 2248 if (!err) 2249 err = dsl_dir_rename(dd, newname); 2250 dsl_dir_close(dd, FTAG); 2251 return (err); 2252 } 2253 if (tail[0] != '@') { 2254 /* the name ended in a nonexistant component */ 2255 dsl_dir_close(dd, FTAG); 2256 return (ENOENT); 2257 } 2258 2259 dsl_dir_close(dd, FTAG); 2260 2261 /* new name must be snapshot in same filesystem */ 2262 tail = strchr(newname, '@'); 2263 if (tail == NULL) 2264 return (EINVAL); 2265 tail++; 2266 if (strncmp(oldname, newname, tail - newname) != 0) 2267 return (EXDEV); 2268 2269 if (recursive) { 2270 err = dsl_recursive_rename(oldname, newname); 2271 } else { 2272 err = dsl_dataset_hold(oldname, FTAG, &ds); 2273 if (err) 2274 return (err); 2275 2276 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2277 dsl_dataset_snapshot_rename_check, 2278 dsl_dataset_snapshot_rename_sync, ds, (char *)tail, 1); 2279 2280 dsl_dataset_rele(ds, FTAG); 2281 } 2282 2283 return (err); 2284 } 2285 2286 struct promotenode { 2287 list_node_t link; 2288 dsl_dataset_t *ds; 2289 }; 2290 2291 struct promotearg { 2292 list_t shared_snaps, origin_snaps, clone_snaps; 2293 dsl_dataset_t *origin_origin, *origin_head; 2294 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2295 }; 2296 2297 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2298 2299 /* ARGSUSED */ 2300 static int 2301 dsl_dataset_promote_check(void *arg1, void *arg2, dmu_tx_t *tx) 2302 { 2303 dsl_dataset_t *hds = arg1; 2304 struct promotearg *pa = arg2; 2305 struct promotenode *snap = list_head(&pa->shared_snaps); 2306 dsl_dataset_t *origin_ds = snap->ds; 2307 int err; 2308 2309 /* Check that it is a real clone */ 2310 if (!dsl_dir_is_clone(hds->ds_dir)) 2311 return (EINVAL); 2312 2313 /* Since this is so expensive, don't do the preliminary check */ 2314 if (!dmu_tx_is_syncing(tx)) 2315 return (0); 2316 2317 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) 2318 return (EXDEV); 2319 2320 /* compute origin's new unique space */ 2321 snap = list_tail(&pa->clone_snaps); 2322 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2323 err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2324 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, &pa->unique); 2325 if (err) 2326 return (err); 2327 2328 /* 2329 * Walk the snapshots that we are moving 2330 * 2331 * Compute space to transfer. Consider the incremental changes 2332 * to used for each snapshot: 2333 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2334 * So each snapshot gave birth to: 2335 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2336 * So a sequence would look like: 2337 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2338 * Which simplifies to: 2339 * uN + kN + kN-1 + ... + k1 + k0 2340 * Note however, if we stop before we reach the ORIGIN we get: 2341 * uN + kN + kN-1 + ... + kM - uM-1 2342 */ 2343 pa->used = origin_ds->ds_phys->ds_used_bytes; 2344 pa->comp = origin_ds->ds_phys->ds_compressed_bytes; 2345 pa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 2346 for (snap = list_head(&pa->shared_snaps); snap; 2347 snap = list_next(&pa->shared_snaps, snap)) { 2348 uint64_t val, dlused, dlcomp, dluncomp; 2349 dsl_dataset_t *ds = snap->ds; 2350 2351 /* Check that the snapshot name does not conflict */ 2352 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2353 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2354 if (err == 0) 2355 return (EEXIST); 2356 if (err != ENOENT) 2357 return (err); 2358 2359 /* The very first snapshot does not have a deadlist */ 2360 if (ds->ds_phys->ds_prev_snap_obj == 0) 2361 continue; 2362 2363 if (err = bplist_space(&ds->ds_deadlist, 2364 &dlused, &dlcomp, &dluncomp)) 2365 return (err); 2366 pa->used += dlused; 2367 pa->comp += dlcomp; 2368 pa->uncomp += dluncomp; 2369 } 2370 2371 /* 2372 * If we are a clone of a clone then we never reached ORIGIN, 2373 * so we need to subtract out the clone origin's used space. 2374 */ 2375 if (pa->origin_origin) { 2376 pa->used -= pa->origin_origin->ds_phys->ds_used_bytes; 2377 pa->comp -= pa->origin_origin->ds_phys->ds_compressed_bytes; 2378 pa->uncomp -= pa->origin_origin->ds_phys->ds_uncompressed_bytes; 2379 } 2380 2381 /* Check that there is enough space here */ 2382 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2383 pa->used); 2384 if (err) 2385 return (err); 2386 2387 /* 2388 * Compute the amounts of space that will be used by snapshots 2389 * after the promotion (for both origin and clone). For each, 2390 * it is the amount of space that will be on all of their 2391 * deadlists (that was not born before their new origin). 2392 */ 2393 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2394 uint64_t space; 2395 2396 /* 2397 * Note, typically this will not be a clone of a clone, 2398 * so snap->ds->ds_origin_txg will be < TXG_INITIAL, so 2399 * these snaplist_space() -> bplist_space_birthrange() 2400 * calls will be fast because they do not have to 2401 * iterate over all bps. 2402 */ 2403 snap = list_head(&pa->origin_snaps); 2404 err = snaplist_space(&pa->shared_snaps, 2405 snap->ds->ds_origin_txg, &pa->cloneusedsnap); 2406 if (err) 2407 return (err); 2408 2409 err = snaplist_space(&pa->clone_snaps, 2410 snap->ds->ds_origin_txg, &space); 2411 if (err) 2412 return (err); 2413 pa->cloneusedsnap += space; 2414 } 2415 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2416 err = snaplist_space(&pa->origin_snaps, 2417 origin_ds->ds_phys->ds_creation_txg, &pa->originusedsnap); 2418 if (err) 2419 return (err); 2420 } 2421 2422 return (0); 2423 } 2424 2425 static void 2426 dsl_dataset_promote_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2427 { 2428 dsl_dataset_t *hds = arg1; 2429 struct promotearg *pa = arg2; 2430 struct promotenode *snap = list_head(&pa->shared_snaps); 2431 dsl_dataset_t *origin_ds = snap->ds; 2432 dsl_dataset_t *origin_head; 2433 dsl_dir_t *dd = hds->ds_dir; 2434 dsl_pool_t *dp = hds->ds_dir->dd_pool; 2435 dsl_dir_t *odd = NULL; 2436 uint64_t oldnext_obj; 2437 int64_t delta; 2438 2439 ASSERT(0 == (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE)); 2440 2441 snap = list_head(&pa->origin_snaps); 2442 origin_head = snap->ds; 2443 2444 /* 2445 * We need to explicitly open odd, since origin_ds's dd will be 2446 * changing. 2447 */ 2448 VERIFY(0 == dsl_dir_open_obj(dp, origin_ds->ds_dir->dd_object, 2449 NULL, FTAG, &odd)); 2450 2451 /* change origin's next snap */ 2452 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2453 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2454 snap = list_tail(&pa->clone_snaps); 2455 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2456 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2457 2458 /* change the origin's next clone */ 2459 if (origin_ds->ds_phys->ds_next_clones_obj) { 2460 VERIFY3U(0, ==, zap_remove_int(dp->dp_meta_objset, 2461 origin_ds->ds_phys->ds_next_clones_obj, 2462 origin_ds->ds_phys->ds_next_snap_obj, tx)); 2463 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset, 2464 origin_ds->ds_phys->ds_next_clones_obj, 2465 oldnext_obj, tx)); 2466 } 2467 2468 /* change origin */ 2469 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2470 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2471 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2472 hds->ds_origin_txg = origin_head->ds_origin_txg; 2473 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2474 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2475 origin_head->ds_origin_txg = origin_ds->ds_phys->ds_creation_txg; 2476 2477 /* move snapshots to this dir */ 2478 for (snap = list_head(&pa->shared_snaps); snap; 2479 snap = list_next(&pa->shared_snaps, snap)) { 2480 dsl_dataset_t *ds = snap->ds; 2481 2482 /* unregister props as dsl_dir is changing */ 2483 if (ds->ds_user_ptr) { 2484 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 2485 ds->ds_user_ptr = NULL; 2486 } 2487 /* move snap name entry */ 2488 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2489 VERIFY(0 == dsl_dataset_snap_remove(origin_head, 2490 ds->ds_snapname, tx)); 2491 VERIFY(0 == zap_add(dp->dp_meta_objset, 2492 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2493 8, 1, &ds->ds_object, tx)); 2494 /* change containing dsl_dir */ 2495 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2496 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2497 ds->ds_phys->ds_dir_obj = dd->dd_object; 2498 ASSERT3P(ds->ds_dir, ==, odd); 2499 dsl_dir_close(ds->ds_dir, ds); 2500 VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object, 2501 NULL, ds, &ds->ds_dir)); 2502 2503 ASSERT3U(dsl_prop_numcb(ds), ==, 0); 2504 } 2505 2506 /* 2507 * Change space accounting. 2508 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2509 * both be valid, or both be 0 (resulting in delta == 0). This 2510 * is true for each of {clone,origin} independently. 2511 */ 2512 2513 delta = pa->cloneusedsnap - 2514 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2515 ASSERT3S(delta, >=, 0); 2516 ASSERT3U(pa->used, >=, delta); 2517 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2518 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2519 pa->used - delta, pa->comp, pa->uncomp, tx); 2520 2521 delta = pa->originusedsnap - 2522 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2523 ASSERT3S(delta, <=, 0); 2524 ASSERT3U(pa->used, >=, -delta); 2525 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2526 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2527 -pa->used - delta, -pa->comp, -pa->uncomp, tx); 2528 2529 origin_ds->ds_phys->ds_unique_bytes = pa->unique; 2530 2531 /* log history record */ 2532 spa_history_internal_log(LOG_DS_PROMOTE, dd->dd_pool->dp_spa, tx, 2533 cr, "dataset = %llu", hds->ds_object); 2534 2535 dsl_dir_close(odd, FTAG); 2536 } 2537 2538 static char *snaplist_tag = "snaplist"; 2539 /* 2540 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2541 * (exclusive) and last_obj (inclusive). The list will be in reverse 2542 * order (last_obj will be the list_head()). If first_obj == 0, do all 2543 * snapshots back to this dataset's origin. 2544 */ 2545 static int 2546 snaplist_make(dsl_pool_t *dp, boolean_t own, 2547 uint64_t first_obj, uint64_t last_obj, list_t *l) 2548 { 2549 uint64_t obj = last_obj; 2550 2551 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock)); 2552 2553 list_create(l, sizeof (struct promotenode), 2554 offsetof(struct promotenode, link)); 2555 2556 while (obj != first_obj) { 2557 dsl_dataset_t *ds; 2558 struct promotenode *snap; 2559 int err; 2560 2561 if (own) { 2562 err = dsl_dataset_own_obj(dp, obj, 2563 0, snaplist_tag, &ds); 2564 if (err == 0) 2565 dsl_dataset_make_exclusive(ds, snaplist_tag); 2566 } else { 2567 err = dsl_dataset_hold_obj(dp, obj, snaplist_tag, &ds); 2568 } 2569 if (err == ENOENT) { 2570 /* lost race with snapshot destroy */ 2571 struct promotenode *last = list_tail(l); 2572 ASSERT(obj != last->ds->ds_phys->ds_prev_snap_obj); 2573 obj = last->ds->ds_phys->ds_prev_snap_obj; 2574 continue; 2575 } else if (err) { 2576 return (err); 2577 } 2578 2579 if (first_obj == 0) 2580 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2581 2582 snap = kmem_alloc(sizeof (struct promotenode), KM_SLEEP); 2583 snap->ds = ds; 2584 list_insert_tail(l, snap); 2585 obj = ds->ds_phys->ds_prev_snap_obj; 2586 } 2587 2588 return (0); 2589 } 2590 2591 static int 2592 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2593 { 2594 struct promotenode *snap; 2595 2596 *spacep = 0; 2597 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2598 uint64_t used; 2599 int err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2600 mintxg, UINT64_MAX, &used); 2601 if (err) 2602 return (err); 2603 *spacep += used; 2604 } 2605 return (0); 2606 } 2607 2608 static void 2609 snaplist_destroy(list_t *l, boolean_t own) 2610 { 2611 struct promotenode *snap; 2612 2613 if (!l || !list_link_active(&l->list_head)) 2614 return; 2615 2616 while ((snap = list_tail(l)) != NULL) { 2617 list_remove(l, snap); 2618 if (own) 2619 dsl_dataset_disown(snap->ds, snaplist_tag); 2620 else 2621 dsl_dataset_rele(snap->ds, snaplist_tag); 2622 kmem_free(snap, sizeof (struct promotenode)); 2623 } 2624 list_destroy(l); 2625 } 2626 2627 /* 2628 * Promote a clone. Nomenclature note: 2629 * "clone" or "cds": the original clone which is being promoted 2630 * "origin" or "ods": the snapshot which is originally clone's origin 2631 * "origin head" or "ohds": the dataset which is the head 2632 * (filesystem/volume) for the origin 2633 * "origin origin": the origin of the origin's filesystem (typically 2634 * NULL, indicating that the clone is not a clone of a clone). 2635 */ 2636 int 2637 dsl_dataset_promote(const char *name) 2638 { 2639 dsl_dataset_t *ds; 2640 dsl_dir_t *dd; 2641 dsl_pool_t *dp; 2642 dmu_object_info_t doi; 2643 struct promotearg pa = { 0 }; 2644 struct promotenode *snap; 2645 int err; 2646 2647 err = dsl_dataset_hold(name, FTAG, &ds); 2648 if (err) 2649 return (err); 2650 dd = ds->ds_dir; 2651 dp = dd->dd_pool; 2652 2653 err = dmu_object_info(dp->dp_meta_objset, 2654 ds->ds_phys->ds_snapnames_zapobj, &doi); 2655 if (err) { 2656 dsl_dataset_rele(ds, FTAG); 2657 return (err); 2658 } 2659 2660 if (dsl_dataset_is_snapshot(ds) || dd->dd_phys->dd_origin_obj == 0) { 2661 dsl_dataset_rele(ds, FTAG); 2662 return (EINVAL); 2663 } 2664 2665 /* 2666 * We are going to inherit all the snapshots taken before our 2667 * origin (i.e., our new origin will be our parent's origin). 2668 * Take ownership of them so that we can rename them into our 2669 * namespace. 2670 */ 2671 rw_enter(&dp->dp_config_rwlock, RW_READER); 2672 2673 err = snaplist_make(dp, B_TRUE, 0, dd->dd_phys->dd_origin_obj, 2674 &pa.shared_snaps); 2675 if (err != 0) 2676 goto out; 2677 2678 err = snaplist_make(dp, B_FALSE, 0, ds->ds_object, &pa.clone_snaps); 2679 if (err != 0) 2680 goto out; 2681 2682 snap = list_head(&pa.shared_snaps); 2683 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2684 err = snaplist_make(dp, B_FALSE, dd->dd_phys->dd_origin_obj, 2685 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, &pa.origin_snaps); 2686 if (err != 0) 2687 goto out; 2688 2689 if (dsl_dir_is_clone(snap->ds->ds_dir)) { 2690 err = dsl_dataset_own_obj(dp, 2691 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2692 0, FTAG, &pa.origin_origin); 2693 if (err != 0) 2694 goto out; 2695 } 2696 2697 out: 2698 rw_exit(&dp->dp_config_rwlock); 2699 2700 /* 2701 * Add in 128x the snapnames zapobj size, since we will be moving 2702 * a bunch of snapnames to the promoted ds, and dirtying their 2703 * bonus buffers. 2704 */ 2705 if (err == 0) { 2706 err = dsl_sync_task_do(dp, dsl_dataset_promote_check, 2707 dsl_dataset_promote_sync, ds, &pa, 2708 2 + 2 * doi.doi_physical_blks); 2709 } 2710 2711 snaplist_destroy(&pa.shared_snaps, B_TRUE); 2712 snaplist_destroy(&pa.clone_snaps, B_FALSE); 2713 snaplist_destroy(&pa.origin_snaps, B_FALSE); 2714 if (pa.origin_origin) 2715 dsl_dataset_disown(pa.origin_origin, FTAG); 2716 dsl_dataset_rele(ds, FTAG); 2717 return (err); 2718 } 2719 2720 struct cloneswaparg { 2721 dsl_dataset_t *cds; /* clone dataset */ 2722 dsl_dataset_t *ohds; /* origin's head dataset */ 2723 boolean_t force; 2724 int64_t unused_refres_delta; /* change in unconsumed refreservation */ 2725 }; 2726 2727 /* ARGSUSED */ 2728 static int 2729 dsl_dataset_clone_swap_check(void *arg1, void *arg2, dmu_tx_t *tx) 2730 { 2731 struct cloneswaparg *csa = arg1; 2732 2733 /* they should both be heads */ 2734 if (dsl_dataset_is_snapshot(csa->cds) || 2735 dsl_dataset_is_snapshot(csa->ohds)) 2736 return (EINVAL); 2737 2738 /* the branch point should be just before them */ 2739 if (csa->cds->ds_prev != csa->ohds->ds_prev) 2740 return (EINVAL); 2741 2742 /* cds should be the clone */ 2743 if (csa->cds->ds_prev->ds_phys->ds_next_snap_obj != 2744 csa->ohds->ds_object) 2745 return (EINVAL); 2746 2747 /* the clone should be a child of the origin */ 2748 if (csa->cds->ds_dir->dd_parent != csa->ohds->ds_dir) 2749 return (EINVAL); 2750 2751 /* ohds shouldn't be modified unless 'force' */ 2752 if (!csa->force && dsl_dataset_modified_since_lastsnap(csa->ohds)) 2753 return (ETXTBSY); 2754 2755 /* adjust amount of any unconsumed refreservation */ 2756 csa->unused_refres_delta = 2757 (int64_t)MIN(csa->ohds->ds_reserved, 2758 csa->ohds->ds_phys->ds_unique_bytes) - 2759 (int64_t)MIN(csa->ohds->ds_reserved, 2760 csa->cds->ds_phys->ds_unique_bytes); 2761 2762 if (csa->unused_refres_delta > 0 && 2763 csa->unused_refres_delta > 2764 dsl_dir_space_available(csa->ohds->ds_dir, NULL, 0, TRUE)) 2765 return (ENOSPC); 2766 2767 return (0); 2768 } 2769 2770 /* ARGSUSED */ 2771 static void 2772 dsl_dataset_clone_swap_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2773 { 2774 struct cloneswaparg *csa = arg1; 2775 dsl_pool_t *dp = csa->cds->ds_dir->dd_pool; 2776 2777 ASSERT(csa->cds->ds_reserved == 0); 2778 ASSERT(csa->cds->ds_quota == csa->ohds->ds_quota); 2779 2780 dmu_buf_will_dirty(csa->cds->ds_dbuf, tx); 2781 dmu_buf_will_dirty(csa->ohds->ds_dbuf, tx); 2782 dmu_buf_will_dirty(csa->cds->ds_prev->ds_dbuf, tx); 2783 2784 if (csa->cds->ds_user_ptr != NULL) { 2785 csa->cds->ds_user_evict_func(csa->cds, csa->cds->ds_user_ptr); 2786 csa->cds->ds_user_ptr = NULL; 2787 } 2788 2789 if (csa->ohds->ds_user_ptr != NULL) { 2790 csa->ohds->ds_user_evict_func(csa->ohds, 2791 csa->ohds->ds_user_ptr); 2792 csa->ohds->ds_user_ptr = NULL; 2793 } 2794 2795 /* reset origin's unique bytes */ 2796 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2797 csa->cds->ds_prev->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2798 &csa->cds->ds_prev->ds_phys->ds_unique_bytes)); 2799 2800 /* swap blkptrs */ 2801 { 2802 blkptr_t tmp; 2803 tmp = csa->ohds->ds_phys->ds_bp; 2804 csa->ohds->ds_phys->ds_bp = csa->cds->ds_phys->ds_bp; 2805 csa->cds->ds_phys->ds_bp = tmp; 2806 } 2807 2808 /* set dd_*_bytes */ 2809 { 2810 int64_t dused, dcomp, duncomp; 2811 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2812 uint64_t odl_used, odl_comp, odl_uncomp; 2813 2814 ASSERT3U(csa->cds->ds_dir->dd_phys-> 2815 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2816 2817 VERIFY(0 == bplist_space(&csa->cds->ds_deadlist, &cdl_used, 2818 &cdl_comp, &cdl_uncomp)); 2819 VERIFY(0 == bplist_space(&csa->ohds->ds_deadlist, &odl_used, 2820 &odl_comp, &odl_uncomp)); 2821 2822 dused = csa->cds->ds_phys->ds_used_bytes + cdl_used - 2823 (csa->ohds->ds_phys->ds_used_bytes + odl_used); 2824 dcomp = csa->cds->ds_phys->ds_compressed_bytes + cdl_comp - 2825 (csa->ohds->ds_phys->ds_compressed_bytes + odl_comp); 2826 duncomp = csa->cds->ds_phys->ds_uncompressed_bytes + 2827 cdl_uncomp - 2828 (csa->ohds->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2829 2830 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_HEAD, 2831 dused, dcomp, duncomp, tx); 2832 dsl_dir_diduse_space(csa->cds->ds_dir, DD_USED_HEAD, 2833 -dused, -dcomp, -duncomp, tx); 2834 2835 /* 2836 * The difference in the space used by snapshots is the 2837 * difference in snapshot space due to the head's 2838 * deadlist (since that's the only thing that's 2839 * changing that affects the snapused). 2840 */ 2841 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2842 csa->ohds->ds_origin_txg, UINT64_MAX, &cdl_used)); 2843 VERIFY(0 == bplist_space_birthrange(&csa->ohds->ds_deadlist, 2844 csa->ohds->ds_origin_txg, UINT64_MAX, &odl_used)); 2845 dsl_dir_transfer_space(csa->ohds->ds_dir, cdl_used - odl_used, 2846 DD_USED_HEAD, DD_USED_SNAP, tx); 2847 } 2848 2849 #define SWITCH64(x, y) \ 2850 { \ 2851 uint64_t __tmp = (x); \ 2852 (x) = (y); \ 2853 (y) = __tmp; \ 2854 } 2855 2856 /* swap ds_*_bytes */ 2857 SWITCH64(csa->ohds->ds_phys->ds_used_bytes, 2858 csa->cds->ds_phys->ds_used_bytes); 2859 SWITCH64(csa->ohds->ds_phys->ds_compressed_bytes, 2860 csa->cds->ds_phys->ds_compressed_bytes); 2861 SWITCH64(csa->ohds->ds_phys->ds_uncompressed_bytes, 2862 csa->cds->ds_phys->ds_uncompressed_bytes); 2863 SWITCH64(csa->ohds->ds_phys->ds_unique_bytes, 2864 csa->cds->ds_phys->ds_unique_bytes); 2865 2866 /* apply any parent delta for change in unconsumed refreservation */ 2867 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_REFRSRV, 2868 csa->unused_refres_delta, 0, 0, tx); 2869 2870 /* swap deadlists */ 2871 bplist_close(&csa->cds->ds_deadlist); 2872 bplist_close(&csa->ohds->ds_deadlist); 2873 SWITCH64(csa->ohds->ds_phys->ds_deadlist_obj, 2874 csa->cds->ds_phys->ds_deadlist_obj); 2875 VERIFY(0 == bplist_open(&csa->cds->ds_deadlist, dp->dp_meta_objset, 2876 csa->cds->ds_phys->ds_deadlist_obj)); 2877 VERIFY(0 == bplist_open(&csa->ohds->ds_deadlist, dp->dp_meta_objset, 2878 csa->ohds->ds_phys->ds_deadlist_obj)); 2879 2880 dsl_pool_ds_clone_swapped(csa->ohds, csa->cds, tx); 2881 } 2882 2883 /* 2884 * Swap 'clone' with its origin head file system. Used at the end 2885 * of "online recv" to swizzle the file system to the new version. 2886 */ 2887 int 2888 dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head, 2889 boolean_t force) 2890 { 2891 struct cloneswaparg csa; 2892 int error; 2893 2894 ASSERT(clone->ds_owner); 2895 ASSERT(origin_head->ds_owner); 2896 retry: 2897 /* Need exclusive access for the swap */ 2898 rw_enter(&clone->ds_rwlock, RW_WRITER); 2899 if (!rw_tryenter(&origin_head->ds_rwlock, RW_WRITER)) { 2900 rw_exit(&clone->ds_rwlock); 2901 rw_enter(&origin_head->ds_rwlock, RW_WRITER); 2902 if (!rw_tryenter(&clone->ds_rwlock, RW_WRITER)) { 2903 rw_exit(&origin_head->ds_rwlock); 2904 goto retry; 2905 } 2906 } 2907 csa.cds = clone; 2908 csa.ohds = origin_head; 2909 csa.force = force; 2910 error = dsl_sync_task_do(clone->ds_dir->dd_pool, 2911 dsl_dataset_clone_swap_check, 2912 dsl_dataset_clone_swap_sync, &csa, NULL, 9); 2913 return (error); 2914 } 2915 2916 /* 2917 * Given a pool name and a dataset object number in that pool, 2918 * return the name of that dataset. 2919 */ 2920 int 2921 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2922 { 2923 spa_t *spa; 2924 dsl_pool_t *dp; 2925 dsl_dataset_t *ds; 2926 int error; 2927 2928 if ((error = spa_open(pname, &spa, FTAG)) != 0) 2929 return (error); 2930 dp = spa_get_dsl(spa); 2931 rw_enter(&dp->dp_config_rwlock, RW_READER); 2932 if ((error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds)) == 0) { 2933 dsl_dataset_name(ds, buf); 2934 dsl_dataset_rele(ds, FTAG); 2935 } 2936 rw_exit(&dp->dp_config_rwlock); 2937 spa_close(spa, FTAG); 2938 2939 return (error); 2940 } 2941 2942 int 2943 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2944 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2945 { 2946 int error = 0; 2947 2948 ASSERT3S(asize, >, 0); 2949 2950 /* 2951 * *ref_rsrv is the portion of asize that will come from any 2952 * unconsumed refreservation space. 2953 */ 2954 *ref_rsrv = 0; 2955 2956 mutex_enter(&ds->ds_lock); 2957 /* 2958 * Make a space adjustment for reserved bytes. 2959 */ 2960 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2961 ASSERT3U(*used, >=, 2962 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2963 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2964 *ref_rsrv = 2965 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2966 } 2967 2968 if (!check_quota || ds->ds_quota == 0) { 2969 mutex_exit(&ds->ds_lock); 2970 return (0); 2971 } 2972 /* 2973 * If they are requesting more space, and our current estimate 2974 * is over quota, they get to try again unless the actual 2975 * on-disk is over quota and there are no pending changes (which 2976 * may free up space for us). 2977 */ 2978 if (ds->ds_phys->ds_used_bytes + inflight >= ds->ds_quota) { 2979 if (inflight > 0 || ds->ds_phys->ds_used_bytes < ds->ds_quota) 2980 error = ERESTART; 2981 else 2982 error = EDQUOT; 2983 } 2984 mutex_exit(&ds->ds_lock); 2985 2986 return (error); 2987 } 2988 2989 /* ARGSUSED */ 2990 static int 2991 dsl_dataset_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx) 2992 { 2993 dsl_dataset_t *ds = arg1; 2994 uint64_t *quotap = arg2; 2995 uint64_t new_quota = *quotap; 2996 2997 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_REFQUOTA) 2998 return (ENOTSUP); 2999 3000 if (new_quota == 0) 3001 return (0); 3002 3003 if (new_quota < ds->ds_phys->ds_used_bytes || 3004 new_quota < ds->ds_reserved) 3005 return (ENOSPC); 3006 3007 return (0); 3008 } 3009 3010 /* ARGSUSED */ 3011 void 3012 dsl_dataset_set_quota_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 3013 { 3014 dsl_dataset_t *ds = arg1; 3015 uint64_t *quotap = arg2; 3016 uint64_t new_quota = *quotap; 3017 3018 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3019 3020 ds->ds_quota = new_quota; 3021 3022 dsl_prop_set_uint64_sync(ds->ds_dir, "refquota", new_quota, cr, tx); 3023 3024 spa_history_internal_log(LOG_DS_REFQUOTA, ds->ds_dir->dd_pool->dp_spa, 3025 tx, cr, "%lld dataset = %llu ", 3026 (longlong_t)new_quota, ds->ds_object); 3027 } 3028 3029 int 3030 dsl_dataset_set_quota(const char *dsname, uint64_t quota) 3031 { 3032 dsl_dataset_t *ds; 3033 int err; 3034 3035 err = dsl_dataset_hold(dsname, FTAG, &ds); 3036 if (err) 3037 return (err); 3038 3039 if (quota != ds->ds_quota) { 3040 /* 3041 * If someone removes a file, then tries to set the quota, we 3042 * want to make sure the file freeing takes effect. 3043 */ 3044 txg_wait_open(ds->ds_dir->dd_pool, 0); 3045 3046 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3047 dsl_dataset_set_quota_check, dsl_dataset_set_quota_sync, 3048 ds, "a, 0); 3049 } 3050 dsl_dataset_rele(ds, FTAG); 3051 return (err); 3052 } 3053 3054 static int 3055 dsl_dataset_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx) 3056 { 3057 dsl_dataset_t *ds = arg1; 3058 uint64_t *reservationp = arg2; 3059 uint64_t new_reservation = *reservationp; 3060 uint64_t unique; 3061 3062 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < 3063 SPA_VERSION_REFRESERVATION) 3064 return (ENOTSUP); 3065 3066 if (dsl_dataset_is_snapshot(ds)) 3067 return (EINVAL); 3068 3069 /* 3070 * If we are doing the preliminary check in open context, the 3071 * space estimates may be inaccurate. 3072 */ 3073 if (!dmu_tx_is_syncing(tx)) 3074 return (0); 3075 3076 mutex_enter(&ds->ds_lock); 3077 unique = dsl_dataset_unique(ds); 3078 mutex_exit(&ds->ds_lock); 3079 3080 if (MAX(unique, new_reservation) > MAX(unique, ds->ds_reserved)) { 3081 uint64_t delta = MAX(unique, new_reservation) - 3082 MAX(unique, ds->ds_reserved); 3083 3084 if (delta > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 3085 return (ENOSPC); 3086 if (ds->ds_quota > 0 && 3087 new_reservation > ds->ds_quota) 3088 return (ENOSPC); 3089 } 3090 3091 return (0); 3092 } 3093 3094 /* ARGSUSED */ 3095 static void 3096 dsl_dataset_set_reservation_sync(void *arg1, void *arg2, cred_t *cr, 3097 dmu_tx_t *tx) 3098 { 3099 dsl_dataset_t *ds = arg1; 3100 uint64_t *reservationp = arg2; 3101 uint64_t new_reservation = *reservationp; 3102 uint64_t unique; 3103 int64_t delta; 3104 3105 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3106 3107 mutex_enter(&ds->ds_dir->dd_lock); 3108 mutex_enter(&ds->ds_lock); 3109 unique = dsl_dataset_unique(ds); 3110 delta = MAX(0, (int64_t)(new_reservation - unique)) - 3111 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3112 ds->ds_reserved = new_reservation; 3113 mutex_exit(&ds->ds_lock); 3114 3115 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3116 mutex_exit(&ds->ds_dir->dd_lock); 3117 dsl_prop_set_uint64_sync(ds->ds_dir, "refreservation", 3118 new_reservation, cr, tx); 3119 3120 spa_history_internal_log(LOG_DS_REFRESERV, 3121 ds->ds_dir->dd_pool->dp_spa, tx, cr, "%lld dataset = %llu", 3122 (longlong_t)new_reservation, ds->ds_object); 3123 } 3124 3125 int 3126 dsl_dataset_set_reservation(const char *dsname, uint64_t reservation) 3127 { 3128 dsl_dataset_t *ds; 3129 int err; 3130 3131 err = dsl_dataset_hold(dsname, FTAG, &ds); 3132 if (err) 3133 return (err); 3134 3135 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3136 dsl_dataset_set_reservation_check, 3137 dsl_dataset_set_reservation_sync, ds, &reservation, 0); 3138 dsl_dataset_rele(ds, FTAG); 3139 return (err); 3140 } 3141