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 return (EBUSY); 552 } 553 return (0); 554 } 555 556 int 557 dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp) 558 { 559 dsl_dir_t *dd; 560 dsl_pool_t *dp; 561 const char *snapname; 562 uint64_t obj; 563 int err = 0; 564 565 err = dsl_dir_open_spa(NULL, name, FTAG, &dd, &snapname); 566 if (err) 567 return (err); 568 569 dp = dd->dd_pool; 570 obj = dd->dd_phys->dd_head_dataset_obj; 571 rw_enter(&dp->dp_config_rwlock, RW_READER); 572 if (obj) 573 err = dsl_dataset_get_ref(dp, obj, tag, dsp); 574 else 575 err = ENOENT; 576 if (err) 577 goto out; 578 579 err = dsl_dataset_hold_ref(*dsp, tag); 580 581 /* we may be looking for a snapshot */ 582 if (err == 0 && snapname != NULL) { 583 dsl_dataset_t *ds = NULL; 584 585 if (*snapname++ != '@') { 586 dsl_dataset_rele(*dsp, tag); 587 err = ENOENT; 588 goto out; 589 } 590 591 dprintf("looking for snapshot '%s'\n", snapname); 592 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 593 if (err == 0) 594 err = dsl_dataset_get_ref(dp, obj, tag, &ds); 595 dsl_dataset_rele(*dsp, tag); 596 597 ASSERT3U((err == 0), ==, (ds != NULL)); 598 599 if (ds) { 600 mutex_enter(&ds->ds_lock); 601 if (ds->ds_snapname[0] == 0) 602 (void) strlcpy(ds->ds_snapname, snapname, 603 sizeof (ds->ds_snapname)); 604 mutex_exit(&ds->ds_lock); 605 err = dsl_dataset_hold_ref(ds, tag); 606 *dsp = err ? NULL : ds; 607 } 608 } 609 out: 610 rw_exit(&dp->dp_config_rwlock); 611 dsl_dir_close(dd, FTAG); 612 return (err); 613 } 614 615 int 616 dsl_dataset_own(const char *name, int flags, void *owner, dsl_dataset_t **dsp) 617 { 618 int err = dsl_dataset_hold(name, owner, dsp); 619 if (err) 620 return (err); 621 if ((*dsp)->ds_phys->ds_num_children > 0 && 622 !DS_MODE_IS_READONLY(flags)) { 623 dsl_dataset_rele(*dsp, owner); 624 return (EROFS); 625 } 626 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 627 dsl_dataset_rele(*dsp, owner); 628 return (EBUSY); 629 } 630 return (0); 631 } 632 633 void 634 dsl_dataset_name(dsl_dataset_t *ds, char *name) 635 { 636 if (ds == NULL) { 637 (void) strcpy(name, "mos"); 638 } else { 639 dsl_dir_name(ds->ds_dir, name); 640 VERIFY(0 == dsl_dataset_get_snapname(ds)); 641 if (ds->ds_snapname[0]) { 642 (void) strcat(name, "@"); 643 /* 644 * We use a "recursive" mutex so that we 645 * can call dprintf_ds() with ds_lock held. 646 */ 647 if (!MUTEX_HELD(&ds->ds_lock)) { 648 mutex_enter(&ds->ds_lock); 649 (void) strcat(name, ds->ds_snapname); 650 mutex_exit(&ds->ds_lock); 651 } else { 652 (void) strcat(name, ds->ds_snapname); 653 } 654 } 655 } 656 } 657 658 static int 659 dsl_dataset_namelen(dsl_dataset_t *ds) 660 { 661 int result; 662 663 if (ds == NULL) { 664 result = 3; /* "mos" */ 665 } else { 666 result = dsl_dir_namelen(ds->ds_dir); 667 VERIFY(0 == dsl_dataset_get_snapname(ds)); 668 if (ds->ds_snapname[0]) { 669 ++result; /* adding one for the @-sign */ 670 if (!MUTEX_HELD(&ds->ds_lock)) { 671 mutex_enter(&ds->ds_lock); 672 result += strlen(ds->ds_snapname); 673 mutex_exit(&ds->ds_lock); 674 } else { 675 result += strlen(ds->ds_snapname); 676 } 677 } 678 } 679 680 return (result); 681 } 682 683 void 684 dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag) 685 { 686 dmu_buf_rele(ds->ds_dbuf, tag); 687 } 688 689 void 690 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 691 { 692 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) { 693 rw_exit(&ds->ds_rwlock); 694 } 695 dsl_dataset_drop_ref(ds, tag); 696 } 697 698 void 699 dsl_dataset_disown(dsl_dataset_t *ds, void *owner) 700 { 701 ASSERT((ds->ds_owner == owner && ds->ds_dbuf) || 702 (DSL_DATASET_IS_DESTROYED(ds) && ds->ds_dbuf == NULL)); 703 704 mutex_enter(&ds->ds_lock); 705 ds->ds_owner = NULL; 706 if (RW_WRITE_HELD(&ds->ds_rwlock)) { 707 rw_exit(&ds->ds_rwlock); 708 cv_broadcast(&ds->ds_exclusive_cv); 709 } 710 mutex_exit(&ds->ds_lock); 711 if (ds->ds_dbuf) 712 dsl_dataset_drop_ref(ds, owner); 713 else 714 dsl_dataset_evict(ds->ds_dbuf, ds); 715 } 716 717 boolean_t 718 dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok, void *owner) 719 { 720 boolean_t gotit = FALSE; 721 722 mutex_enter(&ds->ds_lock); 723 if (ds->ds_owner == NULL && 724 (!DS_IS_INCONSISTENT(ds) || inconsistentok)) { 725 ds->ds_owner = owner; 726 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) 727 rw_exit(&ds->ds_rwlock); 728 gotit = TRUE; 729 } 730 mutex_exit(&ds->ds_lock); 731 return (gotit); 732 } 733 734 void 735 dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *owner) 736 { 737 ASSERT3P(owner, ==, ds->ds_owner); 738 if (!RW_WRITE_HELD(&ds->ds_rwlock)) 739 rw_enter(&ds->ds_rwlock, RW_WRITER); 740 } 741 742 uint64_t 743 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 744 uint64_t flags, dmu_tx_t *tx) 745 { 746 dsl_pool_t *dp = dd->dd_pool; 747 dmu_buf_t *dbuf; 748 dsl_dataset_phys_t *dsphys; 749 uint64_t dsobj; 750 objset_t *mos = dp->dp_meta_objset; 751 752 if (origin == NULL) 753 origin = dp->dp_origin_snap; 754 755 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 756 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 757 ASSERT(dmu_tx_is_syncing(tx)); 758 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 759 760 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 761 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 762 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 763 dmu_buf_will_dirty(dbuf, tx); 764 dsphys = dbuf->db_data; 765 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 766 dsphys->ds_dir_obj = dd->dd_object; 767 dsphys->ds_flags = flags; 768 dsphys->ds_fsid_guid = unique_create(); 769 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 770 sizeof (dsphys->ds_guid)); 771 dsphys->ds_snapnames_zapobj = 772 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 773 DMU_OT_NONE, 0, tx); 774 dsphys->ds_creation_time = gethrestime_sec(); 775 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 776 dsphys->ds_deadlist_obj = 777 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 778 779 if (origin) { 780 dsphys->ds_prev_snap_obj = origin->ds_object; 781 dsphys->ds_prev_snap_txg = 782 origin->ds_phys->ds_creation_txg; 783 dsphys->ds_used_bytes = 784 origin->ds_phys->ds_used_bytes; 785 dsphys->ds_compressed_bytes = 786 origin->ds_phys->ds_compressed_bytes; 787 dsphys->ds_uncompressed_bytes = 788 origin->ds_phys->ds_uncompressed_bytes; 789 dsphys->ds_bp = origin->ds_phys->ds_bp; 790 dsphys->ds_flags |= origin->ds_phys->ds_flags; 791 792 dmu_buf_will_dirty(origin->ds_dbuf, tx); 793 origin->ds_phys->ds_num_children++; 794 795 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 796 if (origin->ds_phys->ds_next_clones_obj == 0) { 797 origin->ds_phys->ds_next_clones_obj = 798 zap_create(mos, 799 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 800 } 801 VERIFY(0 == zap_add_int(mos, 802 origin->ds_phys->ds_next_clones_obj, 803 dsobj, tx)); 804 } 805 806 dmu_buf_will_dirty(dd->dd_dbuf, tx); 807 dd->dd_phys->dd_origin_obj = origin->ds_object; 808 } 809 810 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 811 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 812 813 dmu_buf_rele(dbuf, FTAG); 814 815 dmu_buf_will_dirty(dd->dd_dbuf, tx); 816 dd->dd_phys->dd_head_dataset_obj = dsobj; 817 818 return (dsobj); 819 } 820 821 uint64_t 822 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 823 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 824 { 825 dsl_pool_t *dp = pdd->dd_pool; 826 uint64_t dsobj, ddobj; 827 dsl_dir_t *dd; 828 829 ASSERT(lastname[0] != '@'); 830 831 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 832 VERIFY(0 == dsl_dir_open_obj(dp, ddobj, lastname, FTAG, &dd)); 833 834 dsobj = dsl_dataset_create_sync_dd(dd, origin, flags, tx); 835 836 dsl_deleg_set_create_perms(dd, tx, cr); 837 838 dsl_dir_close(dd, FTAG); 839 840 return (dsobj); 841 } 842 843 struct destroyarg { 844 dsl_sync_task_group_t *dstg; 845 char *snapname; 846 char *failed; 847 }; 848 849 static int 850 dsl_snapshot_destroy_one(char *name, void *arg) 851 { 852 struct destroyarg *da = arg; 853 dsl_dataset_t *ds; 854 char *cp; 855 int err; 856 857 (void) strcat(name, "@"); 858 (void) strcat(name, da->snapname); 859 err = dsl_dataset_own(name, DS_MODE_READONLY | DS_MODE_INCONSISTENT, 860 da->dstg, &ds); 861 cp = strchr(name, '@'); 862 *cp = '\0'; 863 if (err == 0) { 864 dsl_dataset_make_exclusive(ds, da->dstg); 865 if (ds->ds_user_ptr) { 866 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 867 ds->ds_user_ptr = NULL; 868 } 869 dsl_sync_task_create(da->dstg, dsl_dataset_destroy_check, 870 dsl_dataset_destroy_sync, ds, da->dstg, 0); 871 } else if (err == ENOENT) { 872 err = 0; 873 } else { 874 (void) strcpy(da->failed, name); 875 } 876 return (err); 877 } 878 879 /* 880 * Destroy 'snapname' in all descendants of 'fsname'. 881 */ 882 #pragma weak dmu_snapshots_destroy = dsl_snapshots_destroy 883 int 884 dsl_snapshots_destroy(char *fsname, char *snapname) 885 { 886 int err; 887 struct destroyarg da; 888 dsl_sync_task_t *dst; 889 spa_t *spa; 890 891 err = spa_open(fsname, &spa, FTAG); 892 if (err) 893 return (err); 894 da.dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 895 da.snapname = snapname; 896 da.failed = fsname; 897 898 err = dmu_objset_find(fsname, 899 dsl_snapshot_destroy_one, &da, DS_FIND_CHILDREN); 900 901 if (err == 0) 902 err = dsl_sync_task_group_wait(da.dstg); 903 904 for (dst = list_head(&da.dstg->dstg_tasks); dst; 905 dst = list_next(&da.dstg->dstg_tasks, dst)) { 906 dsl_dataset_t *ds = dst->dst_arg1; 907 /* 908 * Return the file system name that triggered the error 909 */ 910 if (dst->dst_err) { 911 dsl_dataset_name(ds, fsname); 912 *strchr(fsname, '@') = '\0'; 913 } 914 dsl_dataset_disown(ds, da.dstg); 915 } 916 917 dsl_sync_task_group_destroy(da.dstg); 918 spa_close(spa, FTAG); 919 return (err); 920 } 921 922 /* 923 * ds must be opened as OWNER. On return (whether successful or not), 924 * ds will be closed and caller can no longer dereference it. 925 */ 926 int 927 dsl_dataset_destroy(dsl_dataset_t *ds, void *tag) 928 { 929 int err; 930 dsl_sync_task_group_t *dstg; 931 objset_t *os; 932 dsl_dir_t *dd; 933 uint64_t obj; 934 935 if (dsl_dataset_is_snapshot(ds)) { 936 /* Destroying a snapshot is simpler */ 937 dsl_dataset_make_exclusive(ds, tag); 938 939 if (ds->ds_user_ptr) { 940 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 941 ds->ds_user_ptr = NULL; 942 } 943 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 944 dsl_dataset_destroy_check, dsl_dataset_destroy_sync, 945 ds, tag, 0); 946 goto out; 947 } 948 949 dd = ds->ds_dir; 950 951 /* 952 * Check for errors and mark this ds as inconsistent, in 953 * case we crash while freeing the objects. 954 */ 955 err = dsl_sync_task_do(dd->dd_pool, dsl_dataset_destroy_begin_check, 956 dsl_dataset_destroy_begin_sync, ds, NULL, 0); 957 if (err) 958 goto out; 959 960 err = dmu_objset_open_ds(ds, DMU_OST_ANY, &os); 961 if (err) 962 goto out; 963 964 /* 965 * remove the objects in open context, so that we won't 966 * have too much to do in syncing context. 967 */ 968 for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 969 ds->ds_phys->ds_prev_snap_txg)) { 970 /* 971 * Ignore errors, if there is not enough disk space 972 * we will deal with it in dsl_dataset_destroy_sync(). 973 */ 974 (void) dmu_free_object(os, obj); 975 } 976 977 dmu_objset_close(os); 978 if (err != ESRCH) 979 goto out; 980 981 rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER); 982 err = dsl_dir_open_obj(dd->dd_pool, dd->dd_object, NULL, FTAG, &dd); 983 rw_exit(&dd->dd_pool->dp_config_rwlock); 984 985 if (err) 986 goto out; 987 988 if (ds->ds_user_ptr) { 989 /* 990 * We need to sync out all in-flight IO before we try 991 * to evict (the dataset evict func is trying to clear 992 * the cached entries for this dataset in the ARC). 993 */ 994 txg_wait_synced(dd->dd_pool, 0); 995 } 996 997 /* 998 * Blow away the dsl_dir + head dataset. 999 */ 1000 dsl_dataset_make_exclusive(ds, tag); 1001 if (ds->ds_user_ptr) { 1002 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1003 ds->ds_user_ptr = NULL; 1004 } 1005 dstg = dsl_sync_task_group_create(ds->ds_dir->dd_pool); 1006 dsl_sync_task_create(dstg, dsl_dataset_destroy_check, 1007 dsl_dataset_destroy_sync, ds, tag, 0); 1008 dsl_sync_task_create(dstg, dsl_dir_destroy_check, 1009 dsl_dir_destroy_sync, dd, FTAG, 0); 1010 err = dsl_sync_task_group_wait(dstg); 1011 dsl_sync_task_group_destroy(dstg); 1012 /* if it is successful, dsl_dir_destroy_sync will close the dd */ 1013 if (err) 1014 dsl_dir_close(dd, FTAG); 1015 out: 1016 dsl_dataset_disown(ds, tag); 1017 return (err); 1018 } 1019 1020 int 1021 dsl_dataset_rollback(dsl_dataset_t *ds, dmu_objset_type_t ost) 1022 { 1023 int err; 1024 1025 ASSERT(ds->ds_owner); 1026 1027 dsl_dataset_make_exclusive(ds, ds->ds_owner); 1028 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 1029 dsl_dataset_rollback_check, dsl_dataset_rollback_sync, 1030 ds, &ost, 0); 1031 /* drop exclusive access */ 1032 mutex_enter(&ds->ds_lock); 1033 rw_exit(&ds->ds_rwlock); 1034 cv_broadcast(&ds->ds_exclusive_cv); 1035 mutex_exit(&ds->ds_lock); 1036 return (err); 1037 } 1038 1039 void * 1040 dsl_dataset_set_user_ptr(dsl_dataset_t *ds, 1041 void *p, dsl_dataset_evict_func_t func) 1042 { 1043 void *old; 1044 1045 mutex_enter(&ds->ds_lock); 1046 old = ds->ds_user_ptr; 1047 if (old == NULL) { 1048 ds->ds_user_ptr = p; 1049 ds->ds_user_evict_func = func; 1050 } 1051 mutex_exit(&ds->ds_lock); 1052 return (old); 1053 } 1054 1055 void * 1056 dsl_dataset_get_user_ptr(dsl_dataset_t *ds) 1057 { 1058 return (ds->ds_user_ptr); 1059 } 1060 1061 1062 blkptr_t * 1063 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1064 { 1065 return (&ds->ds_phys->ds_bp); 1066 } 1067 1068 void 1069 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1070 { 1071 ASSERT(dmu_tx_is_syncing(tx)); 1072 /* If it's the meta-objset, set dp_meta_rootbp */ 1073 if (ds == NULL) { 1074 tx->tx_pool->dp_meta_rootbp = *bp; 1075 } else { 1076 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1077 ds->ds_phys->ds_bp = *bp; 1078 } 1079 } 1080 1081 spa_t * 1082 dsl_dataset_get_spa(dsl_dataset_t *ds) 1083 { 1084 return (ds->ds_dir->dd_pool->dp_spa); 1085 } 1086 1087 void 1088 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1089 { 1090 dsl_pool_t *dp; 1091 1092 if (ds == NULL) /* this is the meta-objset */ 1093 return; 1094 1095 ASSERT(ds->ds_user_ptr != NULL); 1096 1097 if (ds->ds_phys->ds_next_snap_obj != 0) 1098 panic("dirtying snapshot!"); 1099 1100 dp = ds->ds_dir->dd_pool; 1101 1102 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg) == 0) { 1103 /* up the hold count until we can be written out */ 1104 dmu_buf_add_ref(ds->ds_dbuf, ds); 1105 } 1106 } 1107 1108 /* 1109 * The unique space in the head dataset can be calculated by subtracting 1110 * the space used in the most recent snapshot, that is still being used 1111 * in this file system, from the space currently in use. To figure out 1112 * the space in the most recent snapshot still in use, we need to take 1113 * the total space used in the snapshot and subtract out the space that 1114 * has been freed up since the snapshot was taken. 1115 */ 1116 static void 1117 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 1118 { 1119 uint64_t mrs_used; 1120 uint64_t dlused, dlcomp, dluncomp; 1121 1122 ASSERT(ds->ds_object == ds->ds_dir->dd_phys->dd_head_dataset_obj); 1123 1124 if (ds->ds_phys->ds_prev_snap_obj != 0) 1125 mrs_used = ds->ds_prev->ds_phys->ds_used_bytes; 1126 else 1127 mrs_used = 0; 1128 1129 VERIFY(0 == bplist_space(&ds->ds_deadlist, &dlused, &dlcomp, 1130 &dluncomp)); 1131 1132 ASSERT3U(dlused, <=, mrs_used); 1133 ds->ds_phys->ds_unique_bytes = 1134 ds->ds_phys->ds_used_bytes - (mrs_used - dlused); 1135 1136 if (!DS_UNIQUE_IS_ACCURATE(ds) && 1137 spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1138 SPA_VERSION_UNIQUE_ACCURATE) 1139 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1140 } 1141 1142 static uint64_t 1143 dsl_dataset_unique(dsl_dataset_t *ds) 1144 { 1145 if (!DS_UNIQUE_IS_ACCURATE(ds) && !dsl_dataset_is_snapshot(ds)) 1146 dsl_dataset_recalc_head_uniq(ds); 1147 1148 return (ds->ds_phys->ds_unique_bytes); 1149 } 1150 1151 struct killarg { 1152 dsl_dataset_t *ds; 1153 zio_t *zio; 1154 dmu_tx_t *tx; 1155 }; 1156 1157 /* ARGSUSED */ 1158 static int 1159 kill_blkptr(spa_t *spa, blkptr_t *bp, const zbookmark_t *zb, 1160 const dnode_phys_t *dnp, void *arg) 1161 { 1162 struct killarg *ka = arg; 1163 1164 if (bp == NULL) 1165 return (0); 1166 1167 ASSERT3U(bp->blk_birth, >, ka->ds->ds_phys->ds_prev_snap_txg); 1168 (void) dsl_dataset_block_kill(ka->ds, bp, ka->zio, ka->tx); 1169 1170 return (0); 1171 } 1172 1173 /* ARGSUSED */ 1174 static int 1175 dsl_dataset_rollback_check(void *arg1, void *arg2, dmu_tx_t *tx) 1176 { 1177 dsl_dataset_t *ds = arg1; 1178 dmu_objset_type_t *ost = arg2; 1179 1180 /* 1181 * We can only roll back to emptyness if it is a ZPL objset. 1182 */ 1183 if (*ost != DMU_OST_ZFS && ds->ds_phys->ds_prev_snap_txg == 0) 1184 return (EINVAL); 1185 1186 /* 1187 * This must not be a snapshot. 1188 */ 1189 if (ds->ds_phys->ds_next_snap_obj != 0) 1190 return (EINVAL); 1191 1192 /* 1193 * If we made changes this txg, traverse_dataset won't find 1194 * them. Try again. 1195 */ 1196 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1197 return (EAGAIN); 1198 1199 return (0); 1200 } 1201 1202 /* ARGSUSED */ 1203 static void 1204 dsl_dataset_rollback_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1205 { 1206 dsl_dataset_t *ds = arg1; 1207 dmu_objset_type_t *ost = arg2; 1208 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1209 1210 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1211 1212 /* 1213 * Before the roll back destroy the zil. 1214 */ 1215 if (ds->ds_user_ptr != NULL) { 1216 zil_rollback_destroy( 1217 ((objset_impl_t *)ds->ds_user_ptr)->os_zil, tx); 1218 1219 /* 1220 * We need to make sure that the objset_impl_t is reopened after 1221 * we do the rollback, otherwise it will have the wrong 1222 * objset_phys_t. Normally this would happen when this 1223 * dataset-open is closed, thus causing the 1224 * dataset to be immediately evicted. But when doing "zfs recv 1225 * -F", we reopen the objset before that, so that there is no 1226 * window where the dataset is closed and inconsistent. 1227 */ 1228 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1229 ds->ds_user_ptr = NULL; 1230 } 1231 1232 /* Transfer space that was freed since last snap back to the head. */ 1233 { 1234 uint64_t used; 1235 1236 VERIFY(0 == bplist_space_birthrange(&ds->ds_deadlist, 1237 ds->ds_origin_txg, UINT64_MAX, &used)); 1238 dsl_dir_transfer_space(ds->ds_dir, used, 1239 DD_USED_SNAP, DD_USED_HEAD, tx); 1240 } 1241 1242 /* Zero out the deadlist. */ 1243 bplist_close(&ds->ds_deadlist); 1244 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1245 ds->ds_phys->ds_deadlist_obj = 1246 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1247 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1248 ds->ds_phys->ds_deadlist_obj)); 1249 1250 { 1251 /* Free blkptrs that we gave birth to */ 1252 zio_t *zio; 1253 struct killarg ka; 1254 1255 zio = zio_root(tx->tx_pool->dp_spa, NULL, NULL, 1256 ZIO_FLAG_MUSTSUCCEED); 1257 ka.ds = ds; 1258 ka.zio = zio; 1259 ka.tx = tx; 1260 (void) traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1261 TRAVERSE_POST, kill_blkptr, &ka); 1262 (void) zio_wait(zio); 1263 } 1264 1265 ASSERT(!(ds->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) || 1266 ds->ds_phys->ds_unique_bytes == 0); 1267 1268 if (ds->ds_prev && ds->ds_prev != ds->ds_dir->dd_pool->dp_origin_snap) { 1269 /* Change our contents to that of the prev snapshot */ 1270 1271 ASSERT3U(ds->ds_prev->ds_object, ==, 1272 ds->ds_phys->ds_prev_snap_obj); 1273 ASSERT3U(ds->ds_phys->ds_used_bytes, <=, 1274 ds->ds_prev->ds_phys->ds_used_bytes); 1275 1276 ds->ds_phys->ds_bp = ds->ds_prev->ds_phys->ds_bp; 1277 ds->ds_phys->ds_used_bytes = 1278 ds->ds_prev->ds_phys->ds_used_bytes; 1279 ds->ds_phys->ds_compressed_bytes = 1280 ds->ds_prev->ds_phys->ds_compressed_bytes; 1281 ds->ds_phys->ds_uncompressed_bytes = 1282 ds->ds_prev->ds_phys->ds_uncompressed_bytes; 1283 ds->ds_phys->ds_flags = ds->ds_prev->ds_phys->ds_flags; 1284 1285 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1286 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1287 ds->ds_prev->ds_phys->ds_unique_bytes = 0; 1288 } 1289 } else { 1290 objset_impl_t *osi; 1291 1292 ASSERT3U(ds->ds_phys->ds_used_bytes, ==, 0); 1293 ASSERT3U(ds->ds_phys->ds_compressed_bytes, ==, 0); 1294 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, ==, 0); 1295 1296 bzero(&ds->ds_phys->ds_bp, sizeof (blkptr_t)); 1297 ds->ds_phys->ds_flags = 0; 1298 ds->ds_phys->ds_unique_bytes = 0; 1299 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1300 SPA_VERSION_UNIQUE_ACCURATE) 1301 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1302 1303 osi = dmu_objset_create_impl(ds->ds_dir->dd_pool->dp_spa, ds, 1304 &ds->ds_phys->ds_bp, *ost, tx); 1305 #ifdef _KERNEL 1306 zfs_create_fs(&osi->os, kcred, NULL, tx); 1307 #endif 1308 } 1309 1310 spa_history_internal_log(LOG_DS_ROLLBACK, ds->ds_dir->dd_pool->dp_spa, 1311 tx, cr, "dataset = %llu", ds->ds_object); 1312 } 1313 1314 /* ARGSUSED */ 1315 static int 1316 dsl_dataset_destroy_begin_check(void *arg1, void *arg2, dmu_tx_t *tx) 1317 { 1318 dsl_dataset_t *ds = arg1; 1319 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1320 uint64_t count; 1321 int err; 1322 1323 /* 1324 * Can't delete a head dataset if there are snapshots of it. 1325 * (Except if the only snapshots are from the branch we cloned 1326 * from.) 1327 */ 1328 if (ds->ds_prev != NULL && 1329 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1330 return (EINVAL); 1331 1332 /* 1333 * This is really a dsl_dir thing, but check it here so that 1334 * we'll be less likely to leave this dataset inconsistent & 1335 * nearly destroyed. 1336 */ 1337 err = zap_count(mos, ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count); 1338 if (err) 1339 return (err); 1340 if (count != 0) 1341 return (EEXIST); 1342 1343 return (0); 1344 } 1345 1346 /* ARGSUSED */ 1347 static void 1348 dsl_dataset_destroy_begin_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1349 { 1350 dsl_dataset_t *ds = arg1; 1351 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1352 1353 /* Mark it as inconsistent on-disk, in case we crash */ 1354 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1355 ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT; 1356 1357 spa_history_internal_log(LOG_DS_DESTROY_BEGIN, dp->dp_spa, tx, 1358 cr, "dataset = %llu", ds->ds_object); 1359 } 1360 1361 /* ARGSUSED */ 1362 int 1363 dsl_dataset_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx) 1364 { 1365 dsl_dataset_t *ds = arg1; 1366 1367 /* we have an owner hold, so noone else can destroy us */ 1368 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 1369 1370 /* Can't delete a branch point. */ 1371 if (ds->ds_phys->ds_num_children > 1) 1372 return (EEXIST); 1373 1374 /* 1375 * Can't delete a head dataset if there are snapshots of it. 1376 * (Except if the only snapshots are from the branch we cloned 1377 * from.) 1378 */ 1379 if (ds->ds_prev != NULL && 1380 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1381 return (EINVAL); 1382 1383 /* 1384 * If we made changes this txg, traverse_dsl_dataset won't find 1385 * them. Try again. 1386 */ 1387 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1388 return (EAGAIN); 1389 1390 /* XXX we should do some i/o error checking... */ 1391 return (0); 1392 } 1393 1394 struct refsarg { 1395 kmutex_t lock; 1396 boolean_t gone; 1397 kcondvar_t cv; 1398 }; 1399 1400 /* ARGSUSED */ 1401 static void 1402 dsl_dataset_refs_gone(dmu_buf_t *db, void *argv) 1403 { 1404 struct refsarg *arg = argv; 1405 1406 mutex_enter(&arg->lock); 1407 arg->gone = TRUE; 1408 cv_signal(&arg->cv); 1409 mutex_exit(&arg->lock); 1410 } 1411 1412 static void 1413 dsl_dataset_drain_refs(dsl_dataset_t *ds, void *tag) 1414 { 1415 struct refsarg arg; 1416 1417 mutex_init(&arg.lock, NULL, MUTEX_DEFAULT, NULL); 1418 cv_init(&arg.cv, NULL, CV_DEFAULT, NULL); 1419 arg.gone = FALSE; 1420 (void) dmu_buf_update_user(ds->ds_dbuf, ds, &arg, &ds->ds_phys, 1421 dsl_dataset_refs_gone); 1422 dmu_buf_rele(ds->ds_dbuf, tag); 1423 mutex_enter(&arg.lock); 1424 while (!arg.gone) 1425 cv_wait(&arg.cv, &arg.lock); 1426 ASSERT(arg.gone); 1427 mutex_exit(&arg.lock); 1428 ds->ds_dbuf = NULL; 1429 ds->ds_phys = NULL; 1430 mutex_destroy(&arg.lock); 1431 cv_destroy(&arg.cv); 1432 } 1433 1434 void 1435 dsl_dataset_destroy_sync(void *arg1, void *tag, cred_t *cr, dmu_tx_t *tx) 1436 { 1437 dsl_dataset_t *ds = arg1; 1438 zio_t *zio; 1439 int err; 1440 int after_branch_point = FALSE; 1441 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1442 objset_t *mos = dp->dp_meta_objset; 1443 dsl_dataset_t *ds_prev = NULL; 1444 uint64_t obj; 1445 1446 ASSERT(ds->ds_owner); 1447 ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); 1448 ASSERT(ds->ds_prev == NULL || 1449 ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object); 1450 ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); 1451 1452 /* signal any waiters that this dataset is going away */ 1453 mutex_enter(&ds->ds_lock); 1454 ds->ds_owner = dsl_reaper; 1455 cv_broadcast(&ds->ds_exclusive_cv); 1456 mutex_exit(&ds->ds_lock); 1457 1458 /* Remove our reservation */ 1459 if (ds->ds_reserved != 0) { 1460 uint64_t val = 0; 1461 dsl_dataset_set_reservation_sync(ds, &val, cr, tx); 1462 ASSERT3U(ds->ds_reserved, ==, 0); 1463 } 1464 1465 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1466 1467 dsl_pool_ds_destroyed(ds, tx); 1468 1469 obj = ds->ds_object; 1470 1471 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1472 if (ds->ds_prev) { 1473 ds_prev = ds->ds_prev; 1474 } else { 1475 VERIFY(0 == dsl_dataset_hold_obj(dp, 1476 ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev)); 1477 } 1478 after_branch_point = 1479 (ds_prev->ds_phys->ds_next_snap_obj != obj); 1480 1481 dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); 1482 if (after_branch_point && 1483 ds_prev->ds_phys->ds_next_clones_obj != 0) { 1484 VERIFY(0 == zap_remove_int(mos, 1485 ds_prev->ds_phys->ds_next_clones_obj, obj, tx)); 1486 if (ds->ds_phys->ds_next_snap_obj != 0) { 1487 VERIFY(0 == zap_add_int(mos, 1488 ds_prev->ds_phys->ds_next_clones_obj, 1489 ds->ds_phys->ds_next_snap_obj, tx)); 1490 } 1491 } 1492 if (after_branch_point && 1493 ds->ds_phys->ds_next_snap_obj == 0) { 1494 /* This clone is toast. */ 1495 ASSERT(ds_prev->ds_phys->ds_num_children > 1); 1496 ds_prev->ds_phys->ds_num_children--; 1497 } else if (!after_branch_point) { 1498 ds_prev->ds_phys->ds_next_snap_obj = 1499 ds->ds_phys->ds_next_snap_obj; 1500 } 1501 } 1502 1503 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 1504 1505 if (ds->ds_phys->ds_next_snap_obj != 0) { 1506 blkptr_t bp; 1507 dsl_dataset_t *ds_next; 1508 uint64_t itor = 0; 1509 uint64_t old_unique; 1510 int64_t used = 0, compressed = 0, uncompressed = 0; 1511 1512 VERIFY(0 == dsl_dataset_hold_obj(dp, 1513 ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next)); 1514 ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj); 1515 1516 old_unique = dsl_dataset_unique(ds_next); 1517 1518 dmu_buf_will_dirty(ds_next->ds_dbuf, tx); 1519 ds_next->ds_phys->ds_prev_snap_obj = 1520 ds->ds_phys->ds_prev_snap_obj; 1521 ds_next->ds_phys->ds_prev_snap_txg = 1522 ds->ds_phys->ds_prev_snap_txg; 1523 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1524 ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0); 1525 1526 /* 1527 * Transfer to our deadlist (which will become next's 1528 * new deadlist) any entries from next's current 1529 * deadlist which were born before prev, and free the 1530 * other entries. 1531 * 1532 * XXX we're doing this long task with the config lock held 1533 */ 1534 while (bplist_iterate(&ds_next->ds_deadlist, &itor, &bp) == 0) { 1535 if (bp.blk_birth <= ds->ds_phys->ds_prev_snap_txg) { 1536 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, 1537 &bp, tx)); 1538 if (ds_prev && !after_branch_point && 1539 bp.blk_birth > 1540 ds_prev->ds_phys->ds_prev_snap_txg) { 1541 ds_prev->ds_phys->ds_unique_bytes += 1542 bp_get_dasize(dp->dp_spa, &bp); 1543 } 1544 } else { 1545 used += bp_get_dasize(dp->dp_spa, &bp); 1546 compressed += BP_GET_PSIZE(&bp); 1547 uncompressed += BP_GET_UCSIZE(&bp); 1548 /* XXX check return value? */ 1549 (void) dsl_free(zio, dp, tx->tx_txg, 1550 &bp, NULL, NULL, ARC_NOWAIT); 1551 } 1552 } 1553 1554 ASSERT3U(used, ==, ds->ds_phys->ds_unique_bytes); 1555 1556 /* change snapused */ 1557 dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP, 1558 -used, -compressed, -uncompressed, tx); 1559 1560 /* free next's deadlist */ 1561 bplist_close(&ds_next->ds_deadlist); 1562 bplist_destroy(mos, ds_next->ds_phys->ds_deadlist_obj, tx); 1563 1564 /* set next's deadlist to our deadlist */ 1565 bplist_close(&ds->ds_deadlist); 1566 ds_next->ds_phys->ds_deadlist_obj = 1567 ds->ds_phys->ds_deadlist_obj; 1568 VERIFY(0 == bplist_open(&ds_next->ds_deadlist, mos, 1569 ds_next->ds_phys->ds_deadlist_obj)); 1570 ds->ds_phys->ds_deadlist_obj = 0; 1571 1572 if (ds_next->ds_phys->ds_next_snap_obj != 0) { 1573 /* 1574 * Update next's unique to include blocks which 1575 * were previously shared by only this snapshot 1576 * and it. Those blocks will be born after the 1577 * prev snap and before this snap, and will have 1578 * died after the next snap and before the one 1579 * after that (ie. be on the snap after next's 1580 * deadlist). 1581 * 1582 * XXX we're doing this long task with the 1583 * config lock held 1584 */ 1585 dsl_dataset_t *ds_after_next; 1586 uint64_t space; 1587 1588 VERIFY(0 == dsl_dataset_hold_obj(dp, 1589 ds_next->ds_phys->ds_next_snap_obj, 1590 FTAG, &ds_after_next)); 1591 1592 VERIFY(0 == 1593 bplist_space_birthrange(&ds_after_next->ds_deadlist, 1594 ds->ds_phys->ds_prev_snap_txg, 1595 ds->ds_phys->ds_creation_txg, &space)); 1596 ds_next->ds_phys->ds_unique_bytes += space; 1597 1598 dsl_dataset_rele(ds_after_next, FTAG); 1599 ASSERT3P(ds_next->ds_prev, ==, NULL); 1600 } else { 1601 ASSERT3P(ds_next->ds_prev, ==, ds); 1602 dsl_dataset_drop_ref(ds_next->ds_prev, ds_next); 1603 ds_next->ds_prev = NULL; 1604 if (ds_prev) { 1605 VERIFY(0 == dsl_dataset_get_ref(dp, 1606 ds->ds_phys->ds_prev_snap_obj, 1607 ds_next, &ds_next->ds_prev)); 1608 } 1609 1610 dsl_dataset_recalc_head_uniq(ds_next); 1611 1612 /* 1613 * Reduce the amount of our unconsmed refreservation 1614 * being charged to our parent by the amount of 1615 * new unique data we have gained. 1616 */ 1617 if (old_unique < ds_next->ds_reserved) { 1618 int64_t mrsdelta; 1619 uint64_t new_unique = 1620 ds_next->ds_phys->ds_unique_bytes; 1621 1622 ASSERT(old_unique <= new_unique); 1623 mrsdelta = MIN(new_unique - old_unique, 1624 ds_next->ds_reserved - old_unique); 1625 dsl_dir_diduse_space(ds->ds_dir, 1626 DD_USED_REFRSRV, -mrsdelta, 0, 0, tx); 1627 } 1628 } 1629 dsl_dataset_rele(ds_next, FTAG); 1630 } else { 1631 /* 1632 * There's no next snapshot, so this is a head dataset. 1633 * Destroy the deadlist. Unless it's a clone, the 1634 * deadlist should be empty. (If it's a clone, it's 1635 * safe to ignore the deadlist contents.) 1636 */ 1637 struct killarg ka; 1638 1639 ASSERT(after_branch_point || bplist_empty(&ds->ds_deadlist)); 1640 bplist_close(&ds->ds_deadlist); 1641 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1642 ds->ds_phys->ds_deadlist_obj = 0; 1643 1644 /* 1645 * Free everything that we point to (that's born after 1646 * the previous snapshot, if we are a clone) 1647 * 1648 * NB: this should be very quick, because we already 1649 * freed all the objects in open context. 1650 */ 1651 ka.ds = ds; 1652 ka.zio = zio; 1653 ka.tx = tx; 1654 err = traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1655 TRAVERSE_POST, kill_blkptr, &ka); 1656 ASSERT3U(err, ==, 0); 1657 ASSERT(spa_version(dp->dp_spa) < SPA_VERSION_UNIQUE_ACCURATE || 1658 ds->ds_phys->ds_unique_bytes == 0); 1659 } 1660 1661 err = zio_wait(zio); 1662 ASSERT3U(err, ==, 0); 1663 1664 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == ds->ds_object) { 1665 /* Erase the link in the dir */ 1666 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); 1667 ds->ds_dir->dd_phys->dd_head_dataset_obj = 0; 1668 ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0); 1669 err = zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx); 1670 ASSERT(err == 0); 1671 } else { 1672 /* remove from snapshot namespace */ 1673 dsl_dataset_t *ds_head; 1674 ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0); 1675 VERIFY(0 == dsl_dataset_hold_obj(dp, 1676 ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head)); 1677 VERIFY(0 == dsl_dataset_get_snapname(ds)); 1678 #ifdef ZFS_DEBUG 1679 { 1680 uint64_t val; 1681 1682 err = dsl_dataset_snap_lookup(ds_head, 1683 ds->ds_snapname, &val); 1684 ASSERT3U(err, ==, 0); 1685 ASSERT3U(val, ==, obj); 1686 } 1687 #endif 1688 err = dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx); 1689 ASSERT(err == 0); 1690 dsl_dataset_rele(ds_head, FTAG); 1691 } 1692 1693 if (ds_prev && ds->ds_prev != ds_prev) 1694 dsl_dataset_rele(ds_prev, FTAG); 1695 1696 spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); 1697 spa_history_internal_log(LOG_DS_DESTROY, dp->dp_spa, tx, 1698 cr, "dataset = %llu", ds->ds_object); 1699 1700 if (ds->ds_phys->ds_next_clones_obj != 0) { 1701 uint64_t count; 1702 ASSERT(0 == zap_count(mos, 1703 ds->ds_phys->ds_next_clones_obj, &count) && count == 0); 1704 VERIFY(0 == dmu_object_free(mos, 1705 ds->ds_phys->ds_next_clones_obj, tx)); 1706 } 1707 if (ds->ds_phys->ds_props_obj != 0) 1708 VERIFY(0 == zap_destroy(mos, ds->ds_phys->ds_props_obj, tx)); 1709 dsl_dir_close(ds->ds_dir, ds); 1710 ds->ds_dir = NULL; 1711 dsl_dataset_drain_refs(ds, tag); 1712 VERIFY(0 == dmu_object_free(mos, obj, tx)); 1713 } 1714 1715 static int 1716 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1717 { 1718 uint64_t asize; 1719 1720 if (!dmu_tx_is_syncing(tx)) 1721 return (0); 1722 1723 /* 1724 * If there's an fs-only reservation, any blocks that might become 1725 * owned by the snapshot dataset must be accommodated by space 1726 * outside of the reservation. 1727 */ 1728 asize = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1729 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, FALSE)) 1730 return (ENOSPC); 1731 1732 /* 1733 * Propogate any reserved space for this snapshot to other 1734 * snapshot checks in this sync group. 1735 */ 1736 if (asize > 0) 1737 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1738 1739 return (0); 1740 } 1741 1742 /* ARGSUSED */ 1743 int 1744 dsl_dataset_snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx) 1745 { 1746 dsl_dataset_t *ds = arg1; 1747 const char *snapname = arg2; 1748 int err; 1749 uint64_t value; 1750 1751 /* 1752 * We don't allow multiple snapshots of the same txg. If there 1753 * is already one, try again. 1754 */ 1755 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 1756 return (EAGAIN); 1757 1758 /* 1759 * Check for conflicting name snapshot name. 1760 */ 1761 err = dsl_dataset_snap_lookup(ds, snapname, &value); 1762 if (err == 0) 1763 return (EEXIST); 1764 if (err != ENOENT) 1765 return (err); 1766 1767 /* 1768 * Check that the dataset's name is not too long. Name consists 1769 * of the dataset's length + 1 for the @-sign + snapshot name's length 1770 */ 1771 if (dsl_dataset_namelen(ds) + 1 + strlen(snapname) >= MAXNAMELEN) 1772 return (ENAMETOOLONG); 1773 1774 err = dsl_dataset_snapshot_reserve_space(ds, tx); 1775 if (err) 1776 return (err); 1777 1778 ds->ds_trysnap_txg = tx->tx_txg; 1779 return (0); 1780 } 1781 1782 void 1783 dsl_dataset_snapshot_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1784 { 1785 dsl_dataset_t *ds = arg1; 1786 const char *snapname = arg2; 1787 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1788 dmu_buf_t *dbuf; 1789 dsl_dataset_phys_t *dsphys; 1790 uint64_t dsobj, crtxg; 1791 objset_t *mos = dp->dp_meta_objset; 1792 int err; 1793 1794 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1795 1796 /* 1797 * The origin's ds_creation_txg has to be < TXG_INITIAL 1798 */ 1799 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1800 crtxg = 1; 1801 else 1802 crtxg = tx->tx_txg; 1803 1804 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1805 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1806 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1807 dmu_buf_will_dirty(dbuf, tx); 1808 dsphys = dbuf->db_data; 1809 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1810 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1811 dsphys->ds_fsid_guid = unique_create(); 1812 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1813 sizeof (dsphys->ds_guid)); 1814 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1815 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1816 dsphys->ds_next_snap_obj = ds->ds_object; 1817 dsphys->ds_num_children = 1; 1818 dsphys->ds_creation_time = gethrestime_sec(); 1819 dsphys->ds_creation_txg = crtxg; 1820 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1821 dsphys->ds_used_bytes = ds->ds_phys->ds_used_bytes; 1822 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1823 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1824 dsphys->ds_flags = ds->ds_phys->ds_flags; 1825 dsphys->ds_bp = ds->ds_phys->ds_bp; 1826 dmu_buf_rele(dbuf, FTAG); 1827 1828 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1829 if (ds->ds_prev) { 1830 uint64_t next_clones_obj = 1831 ds->ds_prev->ds_phys->ds_next_clones_obj; 1832 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1833 ds->ds_object || 1834 ds->ds_prev->ds_phys->ds_num_children > 1); 1835 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1836 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1837 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1838 ds->ds_prev->ds_phys->ds_creation_txg); 1839 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1840 } else if (next_clones_obj != 0) { 1841 VERIFY3U(0, ==, zap_remove_int(mos, 1842 next_clones_obj, dsphys->ds_next_snap_obj, tx)); 1843 VERIFY3U(0, ==, zap_add_int(mos, 1844 next_clones_obj, dsobj, tx)); 1845 } 1846 } 1847 1848 /* 1849 * If we have a reference-reservation on this dataset, we will 1850 * need to increase the amount of refreservation being charged 1851 * since our unique space is going to zero. 1852 */ 1853 if (ds->ds_reserved) { 1854 int64_t add = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1855 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1856 add, 0, 0, tx); 1857 } 1858 1859 bplist_close(&ds->ds_deadlist); 1860 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1861 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1862 ds->ds_phys->ds_prev_snap_obj = dsobj; 1863 ds->ds_phys->ds_prev_snap_txg = crtxg; 1864 ds->ds_phys->ds_unique_bytes = 0; 1865 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1866 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1867 ds->ds_phys->ds_deadlist_obj = 1868 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1869 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1870 ds->ds_phys->ds_deadlist_obj)); 1871 1872 dprintf("snap '%s' -> obj %llu\n", snapname, dsobj); 1873 err = zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1874 snapname, 8, 1, &dsobj, tx); 1875 ASSERT(err == 0); 1876 1877 if (ds->ds_prev) 1878 dsl_dataset_drop_ref(ds->ds_prev, ds); 1879 VERIFY(0 == dsl_dataset_get_ref(dp, 1880 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1881 1882 dsl_pool_ds_snapshotted(ds, tx); 1883 1884 spa_history_internal_log(LOG_DS_SNAPSHOT, dp->dp_spa, tx, cr, 1885 "dataset = %llu", dsobj); 1886 } 1887 1888 void 1889 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1890 { 1891 ASSERT(dmu_tx_is_syncing(tx)); 1892 ASSERT(ds->ds_user_ptr != NULL); 1893 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1894 1895 /* 1896 * in case we had to change ds_fsid_guid when we opened it, 1897 * sync it out now. 1898 */ 1899 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1900 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1901 1902 dsl_dir_dirty(ds->ds_dir, tx); 1903 dmu_objset_sync(ds->ds_user_ptr, zio, tx); 1904 } 1905 1906 void 1907 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1908 { 1909 uint64_t refd, avail, uobjs, aobjs; 1910 1911 dsl_dir_stats(ds->ds_dir, nv); 1912 1913 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1914 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1915 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1916 1917 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1918 ds->ds_phys->ds_creation_time); 1919 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1920 ds->ds_phys->ds_creation_txg); 1921 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1922 ds->ds_quota); 1923 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1924 ds->ds_reserved); 1925 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1926 ds->ds_phys->ds_guid); 1927 1928 if (ds->ds_phys->ds_next_snap_obj) { 1929 /* 1930 * This is a snapshot; override the dd's space used with 1931 * our unique space and compression ratio. 1932 */ 1933 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1934 ds->ds_phys->ds_unique_bytes); 1935 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, 1936 ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1937 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1938 ds->ds_phys->ds_compressed_bytes)); 1939 } 1940 } 1941 1942 void 1943 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1944 { 1945 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1946 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1947 stat->dds_guid = ds->ds_phys->ds_guid; 1948 if (ds->ds_phys->ds_next_snap_obj) { 1949 stat->dds_is_snapshot = B_TRUE; 1950 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1951 } else { 1952 stat->dds_is_snapshot = B_FALSE; 1953 stat->dds_num_clones = 0; 1954 } 1955 1956 /* clone origin is really a dsl_dir thing... */ 1957 rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER); 1958 if (dsl_dir_is_clone(ds->ds_dir)) { 1959 dsl_dataset_t *ods; 1960 1961 VERIFY(0 == dsl_dataset_get_ref(ds->ds_dir->dd_pool, 1962 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1963 dsl_dataset_name(ods, stat->dds_origin); 1964 dsl_dataset_drop_ref(ods, FTAG); 1965 } else { 1966 stat->dds_origin[0] = '\0'; 1967 } 1968 rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock); 1969 } 1970 1971 uint64_t 1972 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1973 { 1974 return (ds->ds_fsid_guid); 1975 } 1976 1977 void 1978 dsl_dataset_space(dsl_dataset_t *ds, 1979 uint64_t *refdbytesp, uint64_t *availbytesp, 1980 uint64_t *usedobjsp, uint64_t *availobjsp) 1981 { 1982 *refdbytesp = ds->ds_phys->ds_used_bytes; 1983 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1984 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1985 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1986 if (ds->ds_quota != 0) { 1987 /* 1988 * Adjust available bytes according to refquota 1989 */ 1990 if (*refdbytesp < ds->ds_quota) 1991 *availbytesp = MIN(*availbytesp, 1992 ds->ds_quota - *refdbytesp); 1993 else 1994 *availbytesp = 0; 1995 } 1996 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1997 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1998 } 1999 2000 boolean_t 2001 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds) 2002 { 2003 dsl_pool_t *dp = ds->ds_dir->dd_pool; 2004 2005 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 2006 dsl_pool_sync_context(dp)); 2007 if (ds->ds_prev == NULL) 2008 return (B_FALSE); 2009 if (ds->ds_phys->ds_bp.blk_birth > 2010 ds->ds_prev->ds_phys->ds_creation_txg) 2011 return (B_TRUE); 2012 return (B_FALSE); 2013 } 2014 2015 /* ARGSUSED */ 2016 static int 2017 dsl_dataset_snapshot_rename_check(void *arg1, void *arg2, dmu_tx_t *tx) 2018 { 2019 dsl_dataset_t *ds = arg1; 2020 char *newsnapname = arg2; 2021 dsl_dir_t *dd = ds->ds_dir; 2022 dsl_dataset_t *hds; 2023 uint64_t val; 2024 int err; 2025 2026 err = dsl_dataset_hold_obj(dd->dd_pool, 2027 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds); 2028 if (err) 2029 return (err); 2030 2031 /* new name better not be in use */ 2032 err = dsl_dataset_snap_lookup(hds, newsnapname, &val); 2033 dsl_dataset_rele(hds, FTAG); 2034 2035 if (err == 0) 2036 err = EEXIST; 2037 else if (err == ENOENT) 2038 err = 0; 2039 2040 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2041 if (dsl_dir_namelen(ds->ds_dir) + 1 + strlen(newsnapname) >= MAXNAMELEN) 2042 err = ENAMETOOLONG; 2043 2044 return (err); 2045 } 2046 2047 static void 2048 dsl_dataset_snapshot_rename_sync(void *arg1, void *arg2, 2049 cred_t *cr, dmu_tx_t *tx) 2050 { 2051 dsl_dataset_t *ds = arg1; 2052 const char *newsnapname = arg2; 2053 dsl_dir_t *dd = ds->ds_dir; 2054 objset_t *mos = dd->dd_pool->dp_meta_objset; 2055 dsl_dataset_t *hds; 2056 int err; 2057 2058 ASSERT(ds->ds_phys->ds_next_snap_obj != 0); 2059 2060 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, 2061 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds)); 2062 2063 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2064 err = dsl_dataset_snap_remove(hds, ds->ds_snapname, tx); 2065 ASSERT3U(err, ==, 0); 2066 mutex_enter(&ds->ds_lock); 2067 (void) strcpy(ds->ds_snapname, newsnapname); 2068 mutex_exit(&ds->ds_lock); 2069 err = zap_add(mos, hds->ds_phys->ds_snapnames_zapobj, 2070 ds->ds_snapname, 8, 1, &ds->ds_object, tx); 2071 ASSERT3U(err, ==, 0); 2072 2073 spa_history_internal_log(LOG_DS_RENAME, dd->dd_pool->dp_spa, tx, 2074 cr, "dataset = %llu", ds->ds_object); 2075 dsl_dataset_rele(hds, FTAG); 2076 } 2077 2078 struct renamesnaparg { 2079 dsl_sync_task_group_t *dstg; 2080 char failed[MAXPATHLEN]; 2081 char *oldsnap; 2082 char *newsnap; 2083 }; 2084 2085 static int 2086 dsl_snapshot_rename_one(char *name, void *arg) 2087 { 2088 struct renamesnaparg *ra = arg; 2089 dsl_dataset_t *ds = NULL; 2090 char *cp; 2091 int err; 2092 2093 cp = name + strlen(name); 2094 *cp = '@'; 2095 (void) strcpy(cp + 1, ra->oldsnap); 2096 2097 /* 2098 * For recursive snapshot renames the parent won't be changing 2099 * so we just pass name for both the to/from argument. 2100 */ 2101 err = zfs_secpolicy_rename_perms(name, name, CRED()); 2102 if (err == ENOENT) { 2103 return (0); 2104 } else if (err) { 2105 (void) strcpy(ra->failed, name); 2106 return (err); 2107 } 2108 2109 #ifdef _KERNEL 2110 /* 2111 * For all filesystems undergoing rename, we'll need to unmount it. 2112 */ 2113 (void) zfs_unmount_snap(name, NULL); 2114 #endif 2115 err = dsl_dataset_hold(name, ra->dstg, &ds); 2116 *cp = '\0'; 2117 if (err == ENOENT) { 2118 return (0); 2119 } else if (err) { 2120 (void) strcpy(ra->failed, name); 2121 return (err); 2122 } 2123 2124 dsl_sync_task_create(ra->dstg, dsl_dataset_snapshot_rename_check, 2125 dsl_dataset_snapshot_rename_sync, ds, ra->newsnap, 0); 2126 2127 return (0); 2128 } 2129 2130 static int 2131 dsl_recursive_rename(char *oldname, const char *newname) 2132 { 2133 int err; 2134 struct renamesnaparg *ra; 2135 dsl_sync_task_t *dst; 2136 spa_t *spa; 2137 char *cp, *fsname = spa_strdup(oldname); 2138 int len = strlen(oldname); 2139 2140 /* truncate the snapshot name to get the fsname */ 2141 cp = strchr(fsname, '@'); 2142 *cp = '\0'; 2143 2144 err = spa_open(fsname, &spa, FTAG); 2145 if (err) { 2146 kmem_free(fsname, len + 1); 2147 return (err); 2148 } 2149 ra = kmem_alloc(sizeof (struct renamesnaparg), KM_SLEEP); 2150 ra->dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 2151 2152 ra->oldsnap = strchr(oldname, '@') + 1; 2153 ra->newsnap = strchr(newname, '@') + 1; 2154 *ra->failed = '\0'; 2155 2156 err = dmu_objset_find(fsname, dsl_snapshot_rename_one, ra, 2157 DS_FIND_CHILDREN); 2158 kmem_free(fsname, len + 1); 2159 2160 if (err == 0) { 2161 err = dsl_sync_task_group_wait(ra->dstg); 2162 } 2163 2164 for (dst = list_head(&ra->dstg->dstg_tasks); dst; 2165 dst = list_next(&ra->dstg->dstg_tasks, dst)) { 2166 dsl_dataset_t *ds = dst->dst_arg1; 2167 if (dst->dst_err) { 2168 dsl_dir_name(ds->ds_dir, ra->failed); 2169 (void) strcat(ra->failed, "@"); 2170 (void) strcat(ra->failed, ra->newsnap); 2171 } 2172 dsl_dataset_rele(ds, ra->dstg); 2173 } 2174 2175 if (err) 2176 (void) strcpy(oldname, ra->failed); 2177 2178 dsl_sync_task_group_destroy(ra->dstg); 2179 kmem_free(ra, sizeof (struct renamesnaparg)); 2180 spa_close(spa, FTAG); 2181 return (err); 2182 } 2183 2184 static int 2185 dsl_valid_rename(char *oldname, void *arg) 2186 { 2187 int delta = *(int *)arg; 2188 2189 if (strlen(oldname) + delta >= MAXNAMELEN) 2190 return (ENAMETOOLONG); 2191 2192 return (0); 2193 } 2194 2195 #pragma weak dmu_objset_rename = dsl_dataset_rename 2196 int 2197 dsl_dataset_rename(char *oldname, const char *newname, boolean_t recursive) 2198 { 2199 dsl_dir_t *dd; 2200 dsl_dataset_t *ds; 2201 const char *tail; 2202 int err; 2203 2204 err = dsl_dir_open(oldname, FTAG, &dd, &tail); 2205 if (err) 2206 return (err); 2207 /* 2208 * If there are more than 2 references there may be holds 2209 * hanging around that haven't been cleared out yet. 2210 */ 2211 if (dmu_buf_refcount(dd->dd_dbuf) > 2) 2212 txg_wait_synced(dd->dd_pool, 0); 2213 if (tail == NULL) { 2214 int delta = strlen(newname) - strlen(oldname); 2215 2216 /* if we're growing, validate child name lengths */ 2217 if (delta > 0) 2218 err = dmu_objset_find(oldname, dsl_valid_rename, 2219 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS); 2220 2221 if (!err) 2222 err = dsl_dir_rename(dd, newname); 2223 dsl_dir_close(dd, FTAG); 2224 return (err); 2225 } 2226 if (tail[0] != '@') { 2227 /* the name ended in a nonexistant component */ 2228 dsl_dir_close(dd, FTAG); 2229 return (ENOENT); 2230 } 2231 2232 dsl_dir_close(dd, FTAG); 2233 2234 /* new name must be snapshot in same filesystem */ 2235 tail = strchr(newname, '@'); 2236 if (tail == NULL) 2237 return (EINVAL); 2238 tail++; 2239 if (strncmp(oldname, newname, tail - newname) != 0) 2240 return (EXDEV); 2241 2242 if (recursive) { 2243 err = dsl_recursive_rename(oldname, newname); 2244 } else { 2245 err = dsl_dataset_hold(oldname, FTAG, &ds); 2246 if (err) 2247 return (err); 2248 2249 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2250 dsl_dataset_snapshot_rename_check, 2251 dsl_dataset_snapshot_rename_sync, ds, (char *)tail, 1); 2252 2253 dsl_dataset_rele(ds, FTAG); 2254 } 2255 2256 return (err); 2257 } 2258 2259 struct promotenode { 2260 list_node_t link; 2261 dsl_dataset_t *ds; 2262 }; 2263 2264 struct promotearg { 2265 list_t shared_snaps, origin_snaps, clone_snaps; 2266 dsl_dataset_t *origin_origin, *origin_head; 2267 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2268 }; 2269 2270 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2271 2272 /* ARGSUSED */ 2273 static int 2274 dsl_dataset_promote_check(void *arg1, void *arg2, dmu_tx_t *tx) 2275 { 2276 dsl_dataset_t *hds = arg1; 2277 struct promotearg *pa = arg2; 2278 struct promotenode *snap = list_head(&pa->shared_snaps); 2279 dsl_dataset_t *origin_ds = snap->ds; 2280 int err; 2281 2282 /* Check that it is a real clone */ 2283 if (!dsl_dir_is_clone(hds->ds_dir)) 2284 return (EINVAL); 2285 2286 /* Since this is so expensive, don't do the preliminary check */ 2287 if (!dmu_tx_is_syncing(tx)) 2288 return (0); 2289 2290 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) 2291 return (EXDEV); 2292 2293 /* compute origin's new unique space */ 2294 snap = list_tail(&pa->clone_snaps); 2295 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2296 err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2297 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, &pa->unique); 2298 if (err) 2299 return (err); 2300 2301 /* 2302 * Walk the snapshots that we are moving 2303 * 2304 * Compute space to transfer. Consider the incremental changes 2305 * to used for each snapshot: 2306 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2307 * So each snapshot gave birth to: 2308 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2309 * So a sequence would look like: 2310 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2311 * Which simplifies to: 2312 * uN + kN + kN-1 + ... + k1 + k0 2313 * Note however, if we stop before we reach the ORIGIN we get: 2314 * uN + kN + kN-1 + ... + kM - uM-1 2315 */ 2316 pa->used = origin_ds->ds_phys->ds_used_bytes; 2317 pa->comp = origin_ds->ds_phys->ds_compressed_bytes; 2318 pa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 2319 for (snap = list_head(&pa->shared_snaps); snap; 2320 snap = list_next(&pa->shared_snaps, snap)) { 2321 uint64_t val, dlused, dlcomp, dluncomp; 2322 dsl_dataset_t *ds = snap->ds; 2323 2324 /* Check that the snapshot name does not conflict */ 2325 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2326 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2327 if (err == 0) 2328 return (EEXIST); 2329 if (err != ENOENT) 2330 return (err); 2331 2332 /* The very first snapshot does not have a deadlist */ 2333 if (ds->ds_phys->ds_prev_snap_obj == 0) 2334 continue; 2335 2336 if (err = bplist_space(&ds->ds_deadlist, 2337 &dlused, &dlcomp, &dluncomp)) 2338 return (err); 2339 pa->used += dlused; 2340 pa->comp += dlcomp; 2341 pa->uncomp += dluncomp; 2342 } 2343 2344 /* 2345 * If we are a clone of a clone then we never reached ORIGIN, 2346 * so we need to subtract out the clone origin's used space. 2347 */ 2348 if (pa->origin_origin) { 2349 pa->used -= pa->origin_origin->ds_phys->ds_used_bytes; 2350 pa->comp -= pa->origin_origin->ds_phys->ds_compressed_bytes; 2351 pa->uncomp -= pa->origin_origin->ds_phys->ds_uncompressed_bytes; 2352 } 2353 2354 /* Check that there is enough space here */ 2355 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2356 pa->used); 2357 if (err) 2358 return (err); 2359 2360 /* 2361 * Compute the amounts of space that will be used by snapshots 2362 * after the promotion (for both origin and clone). For each, 2363 * it is the amount of space that will be on all of their 2364 * deadlists (that was not born before their new origin). 2365 */ 2366 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2367 uint64_t space; 2368 2369 /* 2370 * Note, typically this will not be a clone of a clone, 2371 * so snap->ds->ds_origin_txg will be < TXG_INITIAL, so 2372 * these snaplist_space() -> bplist_space_birthrange() 2373 * calls will be fast because they do not have to 2374 * iterate over all bps. 2375 */ 2376 snap = list_head(&pa->origin_snaps); 2377 err = snaplist_space(&pa->shared_snaps, 2378 snap->ds->ds_origin_txg, &pa->cloneusedsnap); 2379 if (err) 2380 return (err); 2381 2382 err = snaplist_space(&pa->clone_snaps, 2383 snap->ds->ds_origin_txg, &space); 2384 if (err) 2385 return (err); 2386 pa->cloneusedsnap += space; 2387 } 2388 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2389 err = snaplist_space(&pa->origin_snaps, 2390 origin_ds->ds_phys->ds_creation_txg, &pa->originusedsnap); 2391 if (err) 2392 return (err); 2393 } 2394 2395 return (0); 2396 } 2397 2398 static void 2399 dsl_dataset_promote_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2400 { 2401 dsl_dataset_t *hds = arg1; 2402 struct promotearg *pa = arg2; 2403 struct promotenode *snap = list_head(&pa->shared_snaps); 2404 dsl_dataset_t *origin_ds = snap->ds; 2405 dsl_dataset_t *origin_head; 2406 dsl_dir_t *dd = hds->ds_dir; 2407 dsl_pool_t *dp = hds->ds_dir->dd_pool; 2408 dsl_dir_t *odd = NULL; 2409 uint64_t oldnext_obj; 2410 int64_t delta; 2411 2412 ASSERT(0 == (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE)); 2413 2414 snap = list_head(&pa->origin_snaps); 2415 origin_head = snap->ds; 2416 2417 /* 2418 * We need to explicitly open odd, since origin_ds's dd will be 2419 * changing. 2420 */ 2421 VERIFY(0 == dsl_dir_open_obj(dp, origin_ds->ds_dir->dd_object, 2422 NULL, FTAG, &odd)); 2423 2424 /* change origin's next snap */ 2425 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2426 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2427 snap = list_tail(&pa->clone_snaps); 2428 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2429 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2430 2431 /* change the origin's next clone */ 2432 if (origin_ds->ds_phys->ds_next_clones_obj) { 2433 VERIFY3U(0, ==, zap_remove_int(dp->dp_meta_objset, 2434 origin_ds->ds_phys->ds_next_clones_obj, 2435 origin_ds->ds_phys->ds_next_snap_obj, tx)); 2436 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset, 2437 origin_ds->ds_phys->ds_next_clones_obj, 2438 oldnext_obj, tx)); 2439 } 2440 2441 /* change origin */ 2442 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2443 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2444 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2445 hds->ds_origin_txg = origin_head->ds_origin_txg; 2446 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2447 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2448 origin_head->ds_origin_txg = origin_ds->ds_phys->ds_creation_txg; 2449 2450 /* move snapshots to this dir */ 2451 for (snap = list_head(&pa->shared_snaps); snap; 2452 snap = list_next(&pa->shared_snaps, snap)) { 2453 dsl_dataset_t *ds = snap->ds; 2454 2455 /* unregister props as dsl_dir is changing */ 2456 if (ds->ds_user_ptr) { 2457 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 2458 ds->ds_user_ptr = NULL; 2459 } 2460 /* move snap name entry */ 2461 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2462 VERIFY(0 == dsl_dataset_snap_remove(origin_head, 2463 ds->ds_snapname, tx)); 2464 VERIFY(0 == zap_add(dp->dp_meta_objset, 2465 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2466 8, 1, &ds->ds_object, tx)); 2467 /* change containing dsl_dir */ 2468 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2469 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2470 ds->ds_phys->ds_dir_obj = dd->dd_object; 2471 ASSERT3P(ds->ds_dir, ==, odd); 2472 dsl_dir_close(ds->ds_dir, ds); 2473 VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object, 2474 NULL, ds, &ds->ds_dir)); 2475 2476 ASSERT3U(dsl_prop_numcb(ds), ==, 0); 2477 } 2478 2479 /* 2480 * Change space accounting. 2481 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2482 * both be valid, or both be 0 (resulting in delta == 0). This 2483 * is true for each of {clone,origin} independently. 2484 */ 2485 2486 delta = pa->cloneusedsnap - 2487 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2488 ASSERT3S(delta, >=, 0); 2489 ASSERT3U(pa->used, >=, delta); 2490 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2491 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2492 pa->used - delta, pa->comp, pa->uncomp, tx); 2493 2494 delta = pa->originusedsnap - 2495 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2496 ASSERT3S(delta, <=, 0); 2497 ASSERT3U(pa->used, >=, -delta); 2498 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2499 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2500 -pa->used - delta, -pa->comp, -pa->uncomp, tx); 2501 2502 origin_ds->ds_phys->ds_unique_bytes = pa->unique; 2503 2504 /* log history record */ 2505 spa_history_internal_log(LOG_DS_PROMOTE, dd->dd_pool->dp_spa, tx, 2506 cr, "dataset = %llu", hds->ds_object); 2507 2508 dsl_dir_close(odd, FTAG); 2509 } 2510 2511 static char *snaplist_tag = "snaplist"; 2512 /* 2513 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2514 * (exclusive) and last_obj (inclusive). The list will be in reverse 2515 * order (last_obj will be the list_head()). If first_obj == 0, do all 2516 * snapshots back to this dataset's origin. 2517 */ 2518 static int 2519 snaplist_make(dsl_pool_t *dp, boolean_t own, 2520 uint64_t first_obj, uint64_t last_obj, list_t *l) 2521 { 2522 uint64_t obj = last_obj; 2523 2524 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock)); 2525 2526 list_create(l, sizeof (struct promotenode), 2527 offsetof(struct promotenode, link)); 2528 2529 while (obj != first_obj) { 2530 dsl_dataset_t *ds; 2531 struct promotenode *snap; 2532 int err; 2533 2534 if (own) { 2535 err = dsl_dataset_own_obj(dp, obj, 2536 0, snaplist_tag, &ds); 2537 if (err == 0) 2538 dsl_dataset_make_exclusive(ds, snaplist_tag); 2539 } else { 2540 err = dsl_dataset_hold_obj(dp, obj, snaplist_tag, &ds); 2541 } 2542 if (err == ENOENT) { 2543 /* lost race with snapshot destroy */ 2544 struct promotenode *last = list_tail(l); 2545 ASSERT(obj != last->ds->ds_phys->ds_prev_snap_obj); 2546 obj = last->ds->ds_phys->ds_prev_snap_obj; 2547 continue; 2548 } else if (err) { 2549 return (err); 2550 } 2551 2552 if (first_obj == 0) 2553 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2554 2555 snap = kmem_alloc(sizeof (struct promotenode), KM_SLEEP); 2556 snap->ds = ds; 2557 list_insert_tail(l, snap); 2558 obj = ds->ds_phys->ds_prev_snap_obj; 2559 } 2560 2561 return (0); 2562 } 2563 2564 static int 2565 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2566 { 2567 struct promotenode *snap; 2568 2569 *spacep = 0; 2570 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2571 uint64_t used; 2572 int err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2573 mintxg, UINT64_MAX, &used); 2574 if (err) 2575 return (err); 2576 *spacep += used; 2577 } 2578 return (0); 2579 } 2580 2581 static void 2582 snaplist_destroy(list_t *l, boolean_t own) 2583 { 2584 struct promotenode *snap; 2585 2586 if (!list_link_active(&l->list_head)) 2587 return; 2588 2589 while ((snap = list_tail(l)) != NULL) { 2590 list_remove(l, snap); 2591 if (own) 2592 dsl_dataset_disown(snap->ds, snaplist_tag); 2593 else 2594 dsl_dataset_rele(snap->ds, snaplist_tag); 2595 kmem_free(snap, sizeof (struct promotenode)); 2596 } 2597 list_destroy(l); 2598 } 2599 2600 /* 2601 * Promote a clone. Nomenclature note: 2602 * "clone" or "cds": the original clone which is being promoted 2603 * "origin" or "ods": the snapshot which is originally clone's origin 2604 * "origin head" or "ohds": the dataset which is the head 2605 * (filesystem/volume) for the origin 2606 * "origin origin": the origin of the origin's filesystem (typically 2607 * NULL, indicating that the clone is not a clone of a clone). 2608 */ 2609 int 2610 dsl_dataset_promote(const char *name) 2611 { 2612 dsl_dataset_t *ds; 2613 dsl_dir_t *dd; 2614 dsl_pool_t *dp; 2615 dmu_object_info_t doi; 2616 struct promotearg pa = { 0 }; 2617 struct promotenode *snap; 2618 int err; 2619 2620 err = dsl_dataset_hold(name, FTAG, &ds); 2621 if (err) 2622 return (err); 2623 dd = ds->ds_dir; 2624 dp = dd->dd_pool; 2625 2626 err = dmu_object_info(dp->dp_meta_objset, 2627 ds->ds_phys->ds_snapnames_zapobj, &doi); 2628 if (err) { 2629 dsl_dataset_rele(ds, FTAG); 2630 return (err); 2631 } 2632 2633 if (dsl_dataset_is_snapshot(ds) || dd->dd_phys->dd_origin_obj == 0) { 2634 dsl_dataset_rele(ds, FTAG); 2635 return (EINVAL); 2636 } 2637 2638 /* 2639 * We are going to inherit all the snapshots taken before our 2640 * origin (i.e., our new origin will be our parent's origin). 2641 * Take ownership of them so that we can rename them into our 2642 * namespace. 2643 */ 2644 rw_enter(&dp->dp_config_rwlock, RW_READER); 2645 2646 err = snaplist_make(dp, B_TRUE, 0, dd->dd_phys->dd_origin_obj, 2647 &pa.shared_snaps); 2648 if (err != 0) 2649 goto out; 2650 2651 err = snaplist_make(dp, B_FALSE, 0, ds->ds_object, &pa.clone_snaps); 2652 if (err != 0) 2653 goto out; 2654 2655 snap = list_head(&pa.shared_snaps); 2656 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2657 err = snaplist_make(dp, B_FALSE, dd->dd_phys->dd_origin_obj, 2658 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, &pa.origin_snaps); 2659 if (err != 0) 2660 goto out; 2661 2662 if (dsl_dir_is_clone(snap->ds->ds_dir)) { 2663 err = dsl_dataset_own_obj(dp, 2664 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2665 0, FTAG, &pa.origin_origin); 2666 if (err != 0) 2667 goto out; 2668 } 2669 2670 out: 2671 rw_exit(&dp->dp_config_rwlock); 2672 2673 /* 2674 * Add in 128x the snapnames zapobj size, since we will be moving 2675 * a bunch of snapnames to the promoted ds, and dirtying their 2676 * bonus buffers. 2677 */ 2678 if (err == 0) { 2679 err = dsl_sync_task_do(dp, dsl_dataset_promote_check, 2680 dsl_dataset_promote_sync, ds, &pa, 2681 2 + 2 * doi.doi_physical_blks); 2682 } 2683 2684 snaplist_destroy(&pa.shared_snaps, B_TRUE); 2685 snaplist_destroy(&pa.clone_snaps, B_FALSE); 2686 snaplist_destroy(&pa.origin_snaps, B_FALSE); 2687 if (pa.origin_origin) 2688 dsl_dataset_disown(pa.origin_origin, FTAG); 2689 dsl_dataset_rele(ds, FTAG); 2690 return (err); 2691 } 2692 2693 struct cloneswaparg { 2694 dsl_dataset_t *cds; /* clone dataset */ 2695 dsl_dataset_t *ohds; /* origin's head dataset */ 2696 boolean_t force; 2697 int64_t unused_refres_delta; /* change in unconsumed refreservation */ 2698 }; 2699 2700 /* ARGSUSED */ 2701 static int 2702 dsl_dataset_clone_swap_check(void *arg1, void *arg2, dmu_tx_t *tx) 2703 { 2704 struct cloneswaparg *csa = arg1; 2705 2706 /* they should both be heads */ 2707 if (dsl_dataset_is_snapshot(csa->cds) || 2708 dsl_dataset_is_snapshot(csa->ohds)) 2709 return (EINVAL); 2710 2711 /* the branch point should be just before them */ 2712 if (csa->cds->ds_prev != csa->ohds->ds_prev) 2713 return (EINVAL); 2714 2715 /* cds should be the clone */ 2716 if (csa->cds->ds_prev->ds_phys->ds_next_snap_obj != 2717 csa->ohds->ds_object) 2718 return (EINVAL); 2719 2720 /* the clone should be a child of the origin */ 2721 if (csa->cds->ds_dir->dd_parent != csa->ohds->ds_dir) 2722 return (EINVAL); 2723 2724 /* ohds shouldn't be modified unless 'force' */ 2725 if (!csa->force && dsl_dataset_modified_since_lastsnap(csa->ohds)) 2726 return (ETXTBSY); 2727 2728 /* adjust amount of any unconsumed refreservation */ 2729 csa->unused_refres_delta = 2730 (int64_t)MIN(csa->ohds->ds_reserved, 2731 csa->ohds->ds_phys->ds_unique_bytes) - 2732 (int64_t)MIN(csa->ohds->ds_reserved, 2733 csa->cds->ds_phys->ds_unique_bytes); 2734 2735 if (csa->unused_refres_delta > 0 && 2736 csa->unused_refres_delta > 2737 dsl_dir_space_available(csa->ohds->ds_dir, NULL, 0, TRUE)) 2738 return (ENOSPC); 2739 2740 return (0); 2741 } 2742 2743 /* ARGSUSED */ 2744 static void 2745 dsl_dataset_clone_swap_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2746 { 2747 struct cloneswaparg *csa = arg1; 2748 dsl_pool_t *dp = csa->cds->ds_dir->dd_pool; 2749 2750 ASSERT(csa->cds->ds_reserved == 0); 2751 ASSERT(csa->cds->ds_quota == csa->ohds->ds_quota); 2752 2753 dmu_buf_will_dirty(csa->cds->ds_dbuf, tx); 2754 dmu_buf_will_dirty(csa->ohds->ds_dbuf, tx); 2755 dmu_buf_will_dirty(csa->cds->ds_prev->ds_dbuf, tx); 2756 2757 if (csa->cds->ds_user_ptr != NULL) { 2758 csa->cds->ds_user_evict_func(csa->cds, csa->cds->ds_user_ptr); 2759 csa->cds->ds_user_ptr = NULL; 2760 } 2761 2762 if (csa->ohds->ds_user_ptr != NULL) { 2763 csa->ohds->ds_user_evict_func(csa->ohds, 2764 csa->ohds->ds_user_ptr); 2765 csa->ohds->ds_user_ptr = NULL; 2766 } 2767 2768 /* reset origin's unique bytes */ 2769 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2770 csa->cds->ds_prev->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2771 &csa->cds->ds_prev->ds_phys->ds_unique_bytes)); 2772 2773 /* swap blkptrs */ 2774 { 2775 blkptr_t tmp; 2776 tmp = csa->ohds->ds_phys->ds_bp; 2777 csa->ohds->ds_phys->ds_bp = csa->cds->ds_phys->ds_bp; 2778 csa->cds->ds_phys->ds_bp = tmp; 2779 } 2780 2781 /* set dd_*_bytes */ 2782 { 2783 int64_t dused, dcomp, duncomp; 2784 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2785 uint64_t odl_used, odl_comp, odl_uncomp; 2786 2787 ASSERT3U(csa->cds->ds_dir->dd_phys-> 2788 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2789 2790 VERIFY(0 == bplist_space(&csa->cds->ds_deadlist, &cdl_used, 2791 &cdl_comp, &cdl_uncomp)); 2792 VERIFY(0 == bplist_space(&csa->ohds->ds_deadlist, &odl_used, 2793 &odl_comp, &odl_uncomp)); 2794 2795 dused = csa->cds->ds_phys->ds_used_bytes + cdl_used - 2796 (csa->ohds->ds_phys->ds_used_bytes + odl_used); 2797 dcomp = csa->cds->ds_phys->ds_compressed_bytes + cdl_comp - 2798 (csa->ohds->ds_phys->ds_compressed_bytes + odl_comp); 2799 duncomp = csa->cds->ds_phys->ds_uncompressed_bytes + 2800 cdl_uncomp - 2801 (csa->ohds->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2802 2803 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_HEAD, 2804 dused, dcomp, duncomp, tx); 2805 dsl_dir_diduse_space(csa->cds->ds_dir, DD_USED_HEAD, 2806 -dused, -dcomp, -duncomp, tx); 2807 2808 /* 2809 * The difference in the space used by snapshots is the 2810 * difference in snapshot space due to the head's 2811 * deadlist (since that's the only thing that's 2812 * changing that affects the snapused). 2813 */ 2814 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2815 csa->ohds->ds_origin_txg, UINT64_MAX, &cdl_used)); 2816 VERIFY(0 == bplist_space_birthrange(&csa->ohds->ds_deadlist, 2817 csa->ohds->ds_origin_txg, UINT64_MAX, &odl_used)); 2818 dsl_dir_transfer_space(csa->ohds->ds_dir, cdl_used - odl_used, 2819 DD_USED_HEAD, DD_USED_SNAP, tx); 2820 } 2821 2822 #define SWITCH64(x, y) \ 2823 { \ 2824 uint64_t __tmp = (x); \ 2825 (x) = (y); \ 2826 (y) = __tmp; \ 2827 } 2828 2829 /* swap ds_*_bytes */ 2830 SWITCH64(csa->ohds->ds_phys->ds_used_bytes, 2831 csa->cds->ds_phys->ds_used_bytes); 2832 SWITCH64(csa->ohds->ds_phys->ds_compressed_bytes, 2833 csa->cds->ds_phys->ds_compressed_bytes); 2834 SWITCH64(csa->ohds->ds_phys->ds_uncompressed_bytes, 2835 csa->cds->ds_phys->ds_uncompressed_bytes); 2836 SWITCH64(csa->ohds->ds_phys->ds_unique_bytes, 2837 csa->cds->ds_phys->ds_unique_bytes); 2838 2839 /* apply any parent delta for change in unconsumed refreservation */ 2840 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_REFRSRV, 2841 csa->unused_refres_delta, 0, 0, tx); 2842 2843 /* swap deadlists */ 2844 bplist_close(&csa->cds->ds_deadlist); 2845 bplist_close(&csa->ohds->ds_deadlist); 2846 SWITCH64(csa->ohds->ds_phys->ds_deadlist_obj, 2847 csa->cds->ds_phys->ds_deadlist_obj); 2848 VERIFY(0 == bplist_open(&csa->cds->ds_deadlist, dp->dp_meta_objset, 2849 csa->cds->ds_phys->ds_deadlist_obj)); 2850 VERIFY(0 == bplist_open(&csa->ohds->ds_deadlist, dp->dp_meta_objset, 2851 csa->ohds->ds_phys->ds_deadlist_obj)); 2852 2853 dsl_pool_ds_clone_swapped(csa->ohds, csa->cds, tx); 2854 } 2855 2856 /* 2857 * Swap 'clone' with its origin head file system. Used at the end 2858 * of "online recv" to swizzle the file system to the new version. 2859 */ 2860 int 2861 dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head, 2862 boolean_t force) 2863 { 2864 struct cloneswaparg csa; 2865 int error; 2866 2867 ASSERT(clone->ds_owner); 2868 ASSERT(origin_head->ds_owner); 2869 retry: 2870 /* Need exclusive access for the swap */ 2871 rw_enter(&clone->ds_rwlock, RW_WRITER); 2872 if (!rw_tryenter(&origin_head->ds_rwlock, RW_WRITER)) { 2873 rw_exit(&clone->ds_rwlock); 2874 rw_enter(&origin_head->ds_rwlock, RW_WRITER); 2875 if (!rw_tryenter(&clone->ds_rwlock, RW_WRITER)) { 2876 rw_exit(&origin_head->ds_rwlock); 2877 goto retry; 2878 } 2879 } 2880 csa.cds = clone; 2881 csa.ohds = origin_head; 2882 csa.force = force; 2883 error = dsl_sync_task_do(clone->ds_dir->dd_pool, 2884 dsl_dataset_clone_swap_check, 2885 dsl_dataset_clone_swap_sync, &csa, NULL, 9); 2886 return (error); 2887 } 2888 2889 /* 2890 * Given a pool name and a dataset object number in that pool, 2891 * return the name of that dataset. 2892 */ 2893 int 2894 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2895 { 2896 spa_t *spa; 2897 dsl_pool_t *dp; 2898 dsl_dataset_t *ds; 2899 int error; 2900 2901 if ((error = spa_open(pname, &spa, FTAG)) != 0) 2902 return (error); 2903 dp = spa_get_dsl(spa); 2904 rw_enter(&dp->dp_config_rwlock, RW_READER); 2905 if ((error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds)) == 0) { 2906 dsl_dataset_name(ds, buf); 2907 dsl_dataset_rele(ds, FTAG); 2908 } 2909 rw_exit(&dp->dp_config_rwlock); 2910 spa_close(spa, FTAG); 2911 2912 return (error); 2913 } 2914 2915 int 2916 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2917 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2918 { 2919 int error = 0; 2920 2921 ASSERT3S(asize, >, 0); 2922 2923 /* 2924 * *ref_rsrv is the portion of asize that will come from any 2925 * unconsumed refreservation space. 2926 */ 2927 *ref_rsrv = 0; 2928 2929 mutex_enter(&ds->ds_lock); 2930 /* 2931 * Make a space adjustment for reserved bytes. 2932 */ 2933 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2934 ASSERT3U(*used, >=, 2935 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2936 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2937 *ref_rsrv = 2938 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2939 } 2940 2941 if (!check_quota || ds->ds_quota == 0) { 2942 mutex_exit(&ds->ds_lock); 2943 return (0); 2944 } 2945 /* 2946 * If they are requesting more space, and our current estimate 2947 * is over quota, they get to try again unless the actual 2948 * on-disk is over quota and there are no pending changes (which 2949 * may free up space for us). 2950 */ 2951 if (ds->ds_phys->ds_used_bytes + inflight >= ds->ds_quota) { 2952 if (inflight > 0 || ds->ds_phys->ds_used_bytes < ds->ds_quota) 2953 error = ERESTART; 2954 else 2955 error = EDQUOT; 2956 } 2957 mutex_exit(&ds->ds_lock); 2958 2959 return (error); 2960 } 2961 2962 /* ARGSUSED */ 2963 static int 2964 dsl_dataset_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx) 2965 { 2966 dsl_dataset_t *ds = arg1; 2967 uint64_t *quotap = arg2; 2968 uint64_t new_quota = *quotap; 2969 2970 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_REFQUOTA) 2971 return (ENOTSUP); 2972 2973 if (new_quota == 0) 2974 return (0); 2975 2976 if (new_quota < ds->ds_phys->ds_used_bytes || 2977 new_quota < ds->ds_reserved) 2978 return (ENOSPC); 2979 2980 return (0); 2981 } 2982 2983 /* ARGSUSED */ 2984 void 2985 dsl_dataset_set_quota_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2986 { 2987 dsl_dataset_t *ds = arg1; 2988 uint64_t *quotap = arg2; 2989 uint64_t new_quota = *quotap; 2990 2991 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2992 2993 ds->ds_quota = new_quota; 2994 2995 dsl_prop_set_uint64_sync(ds->ds_dir, "refquota", new_quota, cr, tx); 2996 2997 spa_history_internal_log(LOG_DS_REFQUOTA, ds->ds_dir->dd_pool->dp_spa, 2998 tx, cr, "%lld dataset = %llu ", 2999 (longlong_t)new_quota, ds->ds_object); 3000 } 3001 3002 int 3003 dsl_dataset_set_quota(const char *dsname, uint64_t quota) 3004 { 3005 dsl_dataset_t *ds; 3006 int err; 3007 3008 err = dsl_dataset_hold(dsname, FTAG, &ds); 3009 if (err) 3010 return (err); 3011 3012 if (quota != ds->ds_quota) { 3013 /* 3014 * If someone removes a file, then tries to set the quota, we 3015 * want to make sure the file freeing takes effect. 3016 */ 3017 txg_wait_open(ds->ds_dir->dd_pool, 0); 3018 3019 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3020 dsl_dataset_set_quota_check, dsl_dataset_set_quota_sync, 3021 ds, "a, 0); 3022 } 3023 dsl_dataset_rele(ds, FTAG); 3024 return (err); 3025 } 3026 3027 static int 3028 dsl_dataset_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx) 3029 { 3030 dsl_dataset_t *ds = arg1; 3031 uint64_t *reservationp = arg2; 3032 uint64_t new_reservation = *reservationp; 3033 int64_t delta; 3034 uint64_t unique; 3035 3036 if (new_reservation > INT64_MAX) 3037 return (EOVERFLOW); 3038 3039 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < 3040 SPA_VERSION_REFRESERVATION) 3041 return (ENOTSUP); 3042 3043 if (dsl_dataset_is_snapshot(ds)) 3044 return (EINVAL); 3045 3046 /* 3047 * If we are doing the preliminary check in open context, the 3048 * space estimates may be inaccurate. 3049 */ 3050 if (!dmu_tx_is_syncing(tx)) 3051 return (0); 3052 3053 mutex_enter(&ds->ds_lock); 3054 unique = dsl_dataset_unique(ds); 3055 delta = MAX(unique, new_reservation) - MAX(unique, ds->ds_reserved); 3056 mutex_exit(&ds->ds_lock); 3057 3058 if (delta > 0 && 3059 delta > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 3060 return (ENOSPC); 3061 if (delta > 0 && ds->ds_quota > 0 && 3062 new_reservation > ds->ds_quota) 3063 return (ENOSPC); 3064 3065 return (0); 3066 } 3067 3068 /* ARGSUSED */ 3069 static void 3070 dsl_dataset_set_reservation_sync(void *arg1, void *arg2, cred_t *cr, 3071 dmu_tx_t *tx) 3072 { 3073 dsl_dataset_t *ds = arg1; 3074 uint64_t *reservationp = arg2; 3075 uint64_t new_reservation = *reservationp; 3076 uint64_t unique; 3077 int64_t delta; 3078 3079 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3080 3081 mutex_enter(&ds->ds_dir->dd_lock); 3082 mutex_enter(&ds->ds_lock); 3083 unique = dsl_dataset_unique(ds); 3084 delta = MAX(0, (int64_t)(new_reservation - unique)) - 3085 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3086 ds->ds_reserved = new_reservation; 3087 mutex_exit(&ds->ds_lock); 3088 3089 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3090 mutex_exit(&ds->ds_dir->dd_lock); 3091 dsl_prop_set_uint64_sync(ds->ds_dir, "refreservation", 3092 new_reservation, cr, tx); 3093 3094 spa_history_internal_log(LOG_DS_REFRESERV, 3095 ds->ds_dir->dd_pool->dp_spa, tx, cr, "%lld dataset = %llu", 3096 (longlong_t)new_reservation, ds->ds_object); 3097 } 3098 3099 int 3100 dsl_dataset_set_reservation(const char *dsname, uint64_t reservation) 3101 { 3102 dsl_dataset_t *ds; 3103 int err; 3104 3105 err = dsl_dataset_hold(dsname, FTAG, &ds); 3106 if (err) 3107 return (err); 3108 3109 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3110 dsl_dataset_set_reservation_check, 3111 dsl_dataset_set_reservation_sync, ds, &reservation, 0); 3112 dsl_dataset_rele(ds, FTAG); 3113 return (err); 3114 } 3115