1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/dmu_objset.h> 27 #include <sys/dsl_dataset.h> 28 #include <sys/dsl_dir.h> 29 #include <sys/dsl_prop.h> 30 #include <sys/dsl_synctask.h> 31 #include <sys/dmu_traverse.h> 32 #include <sys/dmu_tx.h> 33 #include <sys/arc.h> 34 #include <sys/zio.h> 35 #include <sys/zap.h> 36 #include <sys/unique.h> 37 #include <sys/zfs_context.h> 38 #include <sys/zfs_ioctl.h> 39 #include <sys/spa.h> 40 #include <sys/zfs_znode.h> 41 #include <sys/sunddi.h> 42 43 static char *dsl_reaper = "the grim reaper"; 44 45 static dsl_checkfunc_t dsl_dataset_destroy_begin_check; 46 static dsl_syncfunc_t dsl_dataset_destroy_begin_sync; 47 static dsl_checkfunc_t dsl_dataset_rollback_check; 48 static dsl_syncfunc_t dsl_dataset_rollback_sync; 49 static dsl_syncfunc_t dsl_dataset_set_reservation_sync; 50 51 #define DS_REF_MAX (1ULL << 62) 52 53 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 54 55 #define DSL_DATASET_IS_DESTROYED(ds) ((ds)->ds_owner == dsl_reaper) 56 57 58 /* 59 * Figure out how much of this delta should be propogated to the dsl_dir 60 * layer. If there's a refreservation, that space has already been 61 * partially accounted for in our ancestors. 62 */ 63 static int64_t 64 parent_delta(dsl_dataset_t *ds, int64_t delta) 65 { 66 uint64_t old_bytes, new_bytes; 67 68 if (ds->ds_reserved == 0) 69 return (delta); 70 71 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 72 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 73 74 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 75 return (new_bytes - old_bytes); 76 } 77 78 void 79 dsl_dataset_block_born(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 80 { 81 int used = bp_get_dasize(tx->tx_pool->dp_spa, bp); 82 int compressed = BP_GET_PSIZE(bp); 83 int uncompressed = BP_GET_UCSIZE(bp); 84 int64_t delta; 85 86 dprintf_bp(bp, "born, ds=%p\n", ds); 87 88 ASSERT(dmu_tx_is_syncing(tx)); 89 /* It could have been compressed away to nothing */ 90 if (BP_IS_HOLE(bp)) 91 return; 92 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 93 ASSERT3U(BP_GET_TYPE(bp), <, DMU_OT_NUMTYPES); 94 if (ds == NULL) { 95 /* 96 * Account for the meta-objset space in its placeholder 97 * dsl_dir. 98 */ 99 ASSERT3U(compressed, ==, uncompressed); /* it's all metadata */ 100 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, DD_USED_HEAD, 101 used, compressed, uncompressed, tx); 102 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx); 103 return; 104 } 105 dmu_buf_will_dirty(ds->ds_dbuf, tx); 106 mutex_enter(&ds->ds_lock); 107 delta = parent_delta(ds, used); 108 ds->ds_phys->ds_used_bytes += used; 109 ds->ds_phys->ds_compressed_bytes += compressed; 110 ds->ds_phys->ds_uncompressed_bytes += uncompressed; 111 ds->ds_phys->ds_unique_bytes += used; 112 mutex_exit(&ds->ds_lock); 113 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta, 114 compressed, uncompressed, tx); 115 dsl_dir_transfer_space(ds->ds_dir, used - delta, 116 DD_USED_REFRSRV, DD_USED_HEAD, tx); 117 } 118 119 int 120 dsl_dataset_block_kill(dsl_dataset_t *ds, blkptr_t *bp, zio_t *pio, 121 dmu_tx_t *tx) 122 { 123 int used = bp_get_dasize(tx->tx_pool->dp_spa, bp); 124 int compressed = BP_GET_PSIZE(bp); 125 int uncompressed = BP_GET_UCSIZE(bp); 126 127 ASSERT(dmu_tx_is_syncing(tx)); 128 /* No block pointer => nothing to free */ 129 if (BP_IS_HOLE(bp)) 130 return (0); 131 132 ASSERT(used > 0); 133 if (ds == NULL) { 134 int err; 135 /* 136 * Account for the meta-objset space in its placeholder 137 * dataset. 138 */ 139 err = dsl_free(pio, tx->tx_pool, 140 tx->tx_txg, bp, NULL, NULL, pio ? ARC_NOWAIT: ARC_WAIT); 141 ASSERT(err == 0); 142 143 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, DD_USED_HEAD, 144 -used, -compressed, -uncompressed, tx); 145 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx); 146 return (used); 147 } 148 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 149 150 ASSERT(!dsl_dataset_is_snapshot(ds)); 151 dmu_buf_will_dirty(ds->ds_dbuf, tx); 152 153 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) { 154 int err; 155 int64_t delta; 156 157 dprintf_bp(bp, "freeing: %s", ""); 158 err = dsl_free(pio, tx->tx_pool, 159 tx->tx_txg, bp, NULL, NULL, pio ? ARC_NOWAIT : ARC_WAIT); 160 ASSERT(err == 0); 161 162 mutex_enter(&ds->ds_lock); 163 ASSERT(ds->ds_phys->ds_unique_bytes >= used || 164 !DS_UNIQUE_IS_ACCURATE(ds)); 165 delta = parent_delta(ds, -used); 166 ds->ds_phys->ds_unique_bytes -= used; 167 mutex_exit(&ds->ds_lock); 168 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, 169 delta, -compressed, -uncompressed, tx); 170 dsl_dir_transfer_space(ds->ds_dir, -used - delta, 171 DD_USED_REFRSRV, DD_USED_HEAD, tx); 172 } else { 173 dprintf_bp(bp, "putting on dead list: %s", ""); 174 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, bp, tx)); 175 ASSERT3U(ds->ds_prev->ds_object, ==, 176 ds->ds_phys->ds_prev_snap_obj); 177 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0); 178 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 179 if (ds->ds_prev->ds_phys->ds_next_snap_obj == 180 ds->ds_object && bp->blk_birth > 181 ds->ds_prev->ds_phys->ds_prev_snap_txg) { 182 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 183 mutex_enter(&ds->ds_prev->ds_lock); 184 ds->ds_prev->ds_phys->ds_unique_bytes += used; 185 mutex_exit(&ds->ds_prev->ds_lock); 186 } 187 if (bp->blk_birth > ds->ds_origin_txg) { 188 dsl_dir_transfer_space(ds->ds_dir, used, 189 DD_USED_HEAD, DD_USED_SNAP, tx); 190 } 191 } 192 mutex_enter(&ds->ds_lock); 193 ASSERT3U(ds->ds_phys->ds_used_bytes, >=, used); 194 ds->ds_phys->ds_used_bytes -= used; 195 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed); 196 ds->ds_phys->ds_compressed_bytes -= compressed; 197 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed); 198 ds->ds_phys->ds_uncompressed_bytes -= uncompressed; 199 mutex_exit(&ds->ds_lock); 200 201 return (used); 202 } 203 204 uint64_t 205 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 206 { 207 uint64_t trysnap = 0; 208 209 if (ds == NULL) 210 return (0); 211 /* 212 * The snapshot creation could fail, but that would cause an 213 * incorrect FALSE return, which would only result in an 214 * overestimation of the amount of space that an operation would 215 * consume, which is OK. 216 * 217 * There's also a small window where we could miss a pending 218 * snapshot, because we could set the sync task in the quiescing 219 * phase. So this should only be used as a guess. 220 */ 221 if (ds->ds_trysnap_txg > 222 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 223 trysnap = ds->ds_trysnap_txg; 224 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap)); 225 } 226 227 int 228 dsl_dataset_block_freeable(dsl_dataset_t *ds, uint64_t blk_birth) 229 { 230 return (blk_birth > dsl_dataset_prev_snap_txg(ds)); 231 } 232 233 /* ARGSUSED */ 234 static void 235 dsl_dataset_evict(dmu_buf_t *db, void *dsv) 236 { 237 dsl_dataset_t *ds = dsv; 238 239 ASSERT(ds->ds_owner == NULL || DSL_DATASET_IS_DESTROYED(ds)); 240 241 dprintf_ds(ds, "evicting %s\n", ""); 242 243 unique_remove(ds->ds_fsid_guid); 244 245 if (ds->ds_user_ptr != NULL) 246 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 247 248 if (ds->ds_prev) { 249 dsl_dataset_drop_ref(ds->ds_prev, ds); 250 ds->ds_prev = NULL; 251 } 252 253 bplist_close(&ds->ds_deadlist); 254 if (ds->ds_dir) 255 dsl_dir_close(ds->ds_dir, ds); 256 257 ASSERT(!list_link_active(&ds->ds_synced_link)); 258 259 mutex_destroy(&ds->ds_lock); 260 mutex_destroy(&ds->ds_opening_lock); 261 mutex_destroy(&ds->ds_deadlist.bpl_lock); 262 rw_destroy(&ds->ds_rwlock); 263 cv_destroy(&ds->ds_exclusive_cv); 264 265 kmem_free(ds, sizeof (dsl_dataset_t)); 266 } 267 268 static int 269 dsl_dataset_get_snapname(dsl_dataset_t *ds) 270 { 271 dsl_dataset_phys_t *headphys; 272 int err; 273 dmu_buf_t *headdbuf; 274 dsl_pool_t *dp = ds->ds_dir->dd_pool; 275 objset_t *mos = dp->dp_meta_objset; 276 277 if (ds->ds_snapname[0]) 278 return (0); 279 if (ds->ds_phys->ds_next_snap_obj == 0) 280 return (0); 281 282 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 283 FTAG, &headdbuf); 284 if (err) 285 return (err); 286 headphys = headdbuf->db_data; 287 err = zap_value_search(dp->dp_meta_objset, 288 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 289 dmu_buf_rele(headdbuf, FTAG); 290 return (err); 291 } 292 293 static int 294 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 295 { 296 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 297 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 298 matchtype_t mt; 299 int err; 300 301 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 302 mt = MT_FIRST; 303 else 304 mt = MT_EXACT; 305 306 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 307 value, mt, NULL, 0, NULL); 308 if (err == ENOTSUP && mt == MT_FIRST) 309 err = zap_lookup(mos, snapobj, name, 8, 1, value); 310 return (err); 311 } 312 313 static int 314 dsl_dataset_snap_remove(dsl_dataset_t *ds, char *name, dmu_tx_t *tx) 315 { 316 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 317 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 318 matchtype_t mt; 319 int err; 320 321 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 322 mt = MT_FIRST; 323 else 324 mt = MT_EXACT; 325 326 err = zap_remove_norm(mos, snapobj, name, mt, tx); 327 if (err == ENOTSUP && mt == MT_FIRST) 328 err = zap_remove(mos, snapobj, name, tx); 329 return (err); 330 } 331 332 static int 333 dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag, 334 dsl_dataset_t **dsp) 335 { 336 objset_t *mos = dp->dp_meta_objset; 337 dmu_buf_t *dbuf; 338 dsl_dataset_t *ds; 339 int err; 340 341 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 342 dsl_pool_sync_context(dp)); 343 344 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 345 if (err) 346 return (err); 347 ds = dmu_buf_get_user(dbuf); 348 if (ds == NULL) { 349 dsl_dataset_t *winner; 350 351 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 352 ds->ds_dbuf = dbuf; 353 ds->ds_object = dsobj; 354 ds->ds_phys = dbuf->db_data; 355 356 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 357 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 358 mutex_init(&ds->ds_deadlist.bpl_lock, NULL, MUTEX_DEFAULT, 359 NULL); 360 rw_init(&ds->ds_rwlock, 0, 0, 0); 361 cv_init(&ds->ds_exclusive_cv, NULL, CV_DEFAULT, NULL); 362 363 err = bplist_open(&ds->ds_deadlist, 364 mos, ds->ds_phys->ds_deadlist_obj); 365 if (err == 0) { 366 err = dsl_dir_open_obj(dp, 367 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 368 } 369 if (err) { 370 /* 371 * we don't really need to close the blist if we 372 * just opened it. 373 */ 374 mutex_destroy(&ds->ds_lock); 375 mutex_destroy(&ds->ds_opening_lock); 376 mutex_destroy(&ds->ds_deadlist.bpl_lock); 377 rw_destroy(&ds->ds_rwlock); 378 cv_destroy(&ds->ds_exclusive_cv); 379 kmem_free(ds, sizeof (dsl_dataset_t)); 380 dmu_buf_rele(dbuf, tag); 381 return (err); 382 } 383 384 if (!dsl_dataset_is_snapshot(ds)) { 385 ds->ds_snapname[0] = '\0'; 386 if (ds->ds_phys->ds_prev_snap_obj) { 387 err = dsl_dataset_get_ref(dp, 388 ds->ds_phys->ds_prev_snap_obj, 389 ds, &ds->ds_prev); 390 } 391 392 if (err == 0 && dsl_dir_is_clone(ds->ds_dir)) { 393 dsl_dataset_t *origin; 394 395 err = dsl_dataset_hold_obj(dp, 396 ds->ds_dir->dd_phys->dd_origin_obj, 397 FTAG, &origin); 398 if (err == 0) { 399 ds->ds_origin_txg = 400 origin->ds_phys->ds_creation_txg; 401 dsl_dataset_rele(origin, FTAG); 402 } 403 } 404 } else if (zfs_flags & ZFS_DEBUG_SNAPNAMES) { 405 err = dsl_dataset_get_snapname(ds); 406 } 407 408 if (err == 0 && !dsl_dataset_is_snapshot(ds)) { 409 /* 410 * In sync context, we're called with either no lock 411 * or with the write lock. If we're not syncing, 412 * we're always called with the read lock held. 413 */ 414 boolean_t need_lock = 415 !RW_WRITE_HELD(&dp->dp_config_rwlock) && 416 dsl_pool_sync_context(dp); 417 418 if (need_lock) 419 rw_enter(&dp->dp_config_rwlock, RW_READER); 420 421 err = dsl_prop_get_ds(ds, 422 "refreservation", sizeof (uint64_t), 1, 423 &ds->ds_reserved, NULL); 424 if (err == 0) { 425 err = dsl_prop_get_ds(ds, 426 "refquota", sizeof (uint64_t), 1, 427 &ds->ds_quota, NULL); 428 } 429 430 if (need_lock) 431 rw_exit(&dp->dp_config_rwlock); 432 } else { 433 ds->ds_reserved = ds->ds_quota = 0; 434 } 435 436 if (err == 0) { 437 winner = dmu_buf_set_user_ie(dbuf, ds, &ds->ds_phys, 438 dsl_dataset_evict); 439 } 440 if (err || winner) { 441 bplist_close(&ds->ds_deadlist); 442 if (ds->ds_prev) 443 dsl_dataset_drop_ref(ds->ds_prev, ds); 444 dsl_dir_close(ds->ds_dir, ds); 445 mutex_destroy(&ds->ds_lock); 446 mutex_destroy(&ds->ds_opening_lock); 447 mutex_destroy(&ds->ds_deadlist.bpl_lock); 448 rw_destroy(&ds->ds_rwlock); 449 cv_destroy(&ds->ds_exclusive_cv); 450 kmem_free(ds, sizeof (dsl_dataset_t)); 451 if (err) { 452 dmu_buf_rele(dbuf, tag); 453 return (err); 454 } 455 ds = winner; 456 } else { 457 ds->ds_fsid_guid = 458 unique_insert(ds->ds_phys->ds_fsid_guid); 459 } 460 } 461 ASSERT3P(ds->ds_dbuf, ==, dbuf); 462 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 463 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 || 464 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN || 465 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap); 466 mutex_enter(&ds->ds_lock); 467 if (!dsl_pool_sync_context(dp) && DSL_DATASET_IS_DESTROYED(ds)) { 468 mutex_exit(&ds->ds_lock); 469 dmu_buf_rele(ds->ds_dbuf, tag); 470 return (ENOENT); 471 } 472 mutex_exit(&ds->ds_lock); 473 *dsp = ds; 474 return (0); 475 } 476 477 static int 478 dsl_dataset_hold_ref(dsl_dataset_t *ds, void *tag) 479 { 480 dsl_pool_t *dp = ds->ds_dir->dd_pool; 481 482 /* 483 * In syncing context we don't want the rwlock lock: there 484 * may be an existing writer waiting for sync phase to 485 * finish. We don't need to worry about such writers, since 486 * sync phase is single-threaded, so the writer can't be 487 * doing anything while we are active. 488 */ 489 if (dsl_pool_sync_context(dp)) { 490 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 491 return (0); 492 } 493 494 /* 495 * Normal users will hold the ds_rwlock as a READER until they 496 * are finished (i.e., call dsl_dataset_rele()). "Owners" will 497 * drop their READER lock after they set the ds_owner field. 498 * 499 * If the dataset is being destroyed, the destroy thread will 500 * obtain a WRITER lock for exclusive access after it's done its 501 * open-context work and then change the ds_owner to 502 * dsl_reaper once destruction is assured. So threads 503 * may block here temporarily, until the "destructability" of 504 * the dataset is determined. 505 */ 506 ASSERT(!RW_WRITE_HELD(&dp->dp_config_rwlock)); 507 mutex_enter(&ds->ds_lock); 508 while (!rw_tryenter(&ds->ds_rwlock, RW_READER)) { 509 rw_exit(&dp->dp_config_rwlock); 510 cv_wait(&ds->ds_exclusive_cv, &ds->ds_lock); 511 if (DSL_DATASET_IS_DESTROYED(ds)) { 512 mutex_exit(&ds->ds_lock); 513 dsl_dataset_drop_ref(ds, tag); 514 rw_enter(&dp->dp_config_rwlock, RW_READER); 515 return (ENOENT); 516 } 517 rw_enter(&dp->dp_config_rwlock, RW_READER); 518 } 519 mutex_exit(&ds->ds_lock); 520 return (0); 521 } 522 523 int 524 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 525 dsl_dataset_t **dsp) 526 { 527 int err = dsl_dataset_get_ref(dp, dsobj, tag, dsp); 528 529 if (err) 530 return (err); 531 return (dsl_dataset_hold_ref(*dsp, tag)); 532 } 533 534 int 535 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, int flags, void *owner, 536 dsl_dataset_t **dsp) 537 { 538 int err = dsl_dataset_hold_obj(dp, dsobj, owner, dsp); 539 540 ASSERT(DS_MODE_TYPE(flags) != DS_MODE_USER); 541 542 if (err) 543 return (err); 544 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 545 dsl_dataset_rele(*dsp, owner); 546 return (EBUSY); 547 } 548 return (0); 549 } 550 551 int 552 dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp) 553 { 554 dsl_dir_t *dd; 555 dsl_pool_t *dp; 556 const char *snapname; 557 uint64_t obj; 558 int err = 0; 559 560 err = dsl_dir_open_spa(NULL, name, FTAG, &dd, &snapname); 561 if (err) 562 return (err); 563 564 dp = dd->dd_pool; 565 obj = dd->dd_phys->dd_head_dataset_obj; 566 rw_enter(&dp->dp_config_rwlock, RW_READER); 567 if (obj) 568 err = dsl_dataset_get_ref(dp, obj, tag, dsp); 569 else 570 err = ENOENT; 571 if (err) 572 goto out; 573 574 err = dsl_dataset_hold_ref(*dsp, tag); 575 576 /* we may be looking for a snapshot */ 577 if (err == 0 && snapname != NULL) { 578 dsl_dataset_t *ds = NULL; 579 580 if (*snapname++ != '@') { 581 dsl_dataset_rele(*dsp, tag); 582 err = ENOENT; 583 goto out; 584 } 585 586 dprintf("looking for snapshot '%s'\n", snapname); 587 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 588 if (err == 0) 589 err = dsl_dataset_get_ref(dp, obj, tag, &ds); 590 dsl_dataset_rele(*dsp, tag); 591 592 ASSERT3U((err == 0), ==, (ds != NULL)); 593 594 if (ds) { 595 mutex_enter(&ds->ds_lock); 596 if (ds->ds_snapname[0] == 0) 597 (void) strlcpy(ds->ds_snapname, snapname, 598 sizeof (ds->ds_snapname)); 599 mutex_exit(&ds->ds_lock); 600 err = dsl_dataset_hold_ref(ds, tag); 601 *dsp = err ? NULL : ds; 602 } 603 } 604 out: 605 rw_exit(&dp->dp_config_rwlock); 606 dsl_dir_close(dd, FTAG); 607 return (err); 608 } 609 610 int 611 dsl_dataset_own(const char *name, int flags, void *owner, dsl_dataset_t **dsp) 612 { 613 int err = dsl_dataset_hold(name, owner, dsp); 614 if (err) 615 return (err); 616 if ((*dsp)->ds_phys->ds_num_children > 0 && 617 !DS_MODE_IS_READONLY(flags)) { 618 dsl_dataset_rele(*dsp, owner); 619 return (EROFS); 620 } 621 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 622 dsl_dataset_rele(*dsp, owner); 623 return (EBUSY); 624 } 625 return (0); 626 } 627 628 void 629 dsl_dataset_name(dsl_dataset_t *ds, char *name) 630 { 631 if (ds == NULL) { 632 (void) strcpy(name, "mos"); 633 } else { 634 dsl_dir_name(ds->ds_dir, name); 635 VERIFY(0 == dsl_dataset_get_snapname(ds)); 636 if (ds->ds_snapname[0]) { 637 (void) strcat(name, "@"); 638 /* 639 * We use a "recursive" mutex so that we 640 * can call dprintf_ds() with ds_lock held. 641 */ 642 if (!MUTEX_HELD(&ds->ds_lock)) { 643 mutex_enter(&ds->ds_lock); 644 (void) strcat(name, ds->ds_snapname); 645 mutex_exit(&ds->ds_lock); 646 } else { 647 (void) strcat(name, ds->ds_snapname); 648 } 649 } 650 } 651 } 652 653 static int 654 dsl_dataset_namelen(dsl_dataset_t *ds) 655 { 656 int result; 657 658 if (ds == NULL) { 659 result = 3; /* "mos" */ 660 } else { 661 result = dsl_dir_namelen(ds->ds_dir); 662 VERIFY(0 == dsl_dataset_get_snapname(ds)); 663 if (ds->ds_snapname[0]) { 664 ++result; /* adding one for the @-sign */ 665 if (!MUTEX_HELD(&ds->ds_lock)) { 666 mutex_enter(&ds->ds_lock); 667 result += strlen(ds->ds_snapname); 668 mutex_exit(&ds->ds_lock); 669 } else { 670 result += strlen(ds->ds_snapname); 671 } 672 } 673 } 674 675 return (result); 676 } 677 678 void 679 dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag) 680 { 681 dmu_buf_rele(ds->ds_dbuf, tag); 682 } 683 684 void 685 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 686 { 687 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) { 688 rw_exit(&ds->ds_rwlock); 689 } 690 dsl_dataset_drop_ref(ds, tag); 691 } 692 693 void 694 dsl_dataset_disown(dsl_dataset_t *ds, void *owner) 695 { 696 ASSERT((ds->ds_owner == owner && ds->ds_dbuf) || 697 (DSL_DATASET_IS_DESTROYED(ds) && ds->ds_dbuf == NULL)); 698 699 mutex_enter(&ds->ds_lock); 700 ds->ds_owner = NULL; 701 if (RW_WRITE_HELD(&ds->ds_rwlock)) { 702 rw_exit(&ds->ds_rwlock); 703 cv_broadcast(&ds->ds_exclusive_cv); 704 } 705 mutex_exit(&ds->ds_lock); 706 if (ds->ds_dbuf) 707 dsl_dataset_drop_ref(ds, owner); 708 else 709 dsl_dataset_evict(ds->ds_dbuf, ds); 710 } 711 712 boolean_t 713 dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok, void *owner) 714 { 715 boolean_t gotit = FALSE; 716 717 mutex_enter(&ds->ds_lock); 718 if (ds->ds_owner == NULL && 719 (!DS_IS_INCONSISTENT(ds) || inconsistentok)) { 720 ds->ds_owner = owner; 721 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) 722 rw_exit(&ds->ds_rwlock); 723 gotit = TRUE; 724 } 725 mutex_exit(&ds->ds_lock); 726 return (gotit); 727 } 728 729 void 730 dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *owner) 731 { 732 ASSERT3P(owner, ==, ds->ds_owner); 733 if (!RW_WRITE_HELD(&ds->ds_rwlock)) 734 rw_enter(&ds->ds_rwlock, RW_WRITER); 735 } 736 737 uint64_t 738 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin, 739 uint64_t flags, dmu_tx_t *tx) 740 { 741 dsl_pool_t *dp = dd->dd_pool; 742 dmu_buf_t *dbuf; 743 dsl_dataset_phys_t *dsphys; 744 uint64_t dsobj; 745 objset_t *mos = dp->dp_meta_objset; 746 747 if (origin == NULL) 748 origin = dp->dp_origin_snap; 749 750 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 751 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 752 ASSERT(dmu_tx_is_syncing(tx)); 753 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 754 755 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 756 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 757 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 758 dmu_buf_will_dirty(dbuf, tx); 759 dsphys = dbuf->db_data; 760 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 761 dsphys->ds_dir_obj = dd->dd_object; 762 dsphys->ds_flags = flags; 763 dsphys->ds_fsid_guid = unique_create(); 764 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 765 sizeof (dsphys->ds_guid)); 766 dsphys->ds_snapnames_zapobj = 767 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 768 DMU_OT_NONE, 0, tx); 769 dsphys->ds_creation_time = gethrestime_sec(); 770 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg; 771 dsphys->ds_deadlist_obj = 772 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 773 774 if (origin) { 775 dsphys->ds_prev_snap_obj = origin->ds_object; 776 dsphys->ds_prev_snap_txg = 777 origin->ds_phys->ds_creation_txg; 778 dsphys->ds_used_bytes = 779 origin->ds_phys->ds_used_bytes; 780 dsphys->ds_compressed_bytes = 781 origin->ds_phys->ds_compressed_bytes; 782 dsphys->ds_uncompressed_bytes = 783 origin->ds_phys->ds_uncompressed_bytes; 784 dsphys->ds_bp = origin->ds_phys->ds_bp; 785 dsphys->ds_flags |= origin->ds_phys->ds_flags; 786 787 dmu_buf_will_dirty(origin->ds_dbuf, tx); 788 origin->ds_phys->ds_num_children++; 789 790 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) { 791 if (origin->ds_phys->ds_next_clones_obj == 0) { 792 origin->ds_phys->ds_next_clones_obj = 793 zap_create(mos, 794 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 795 } 796 VERIFY(0 == zap_add_int(mos, 797 origin->ds_phys->ds_next_clones_obj, 798 dsobj, tx)); 799 } 800 801 dmu_buf_will_dirty(dd->dd_dbuf, tx); 802 dd->dd_phys->dd_origin_obj = origin->ds_object; 803 } 804 805 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 806 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 807 808 dmu_buf_rele(dbuf, FTAG); 809 810 dmu_buf_will_dirty(dd->dd_dbuf, tx); 811 dd->dd_phys->dd_head_dataset_obj = dsobj; 812 813 return (dsobj); 814 } 815 816 uint64_t 817 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 818 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 819 { 820 dsl_pool_t *dp = pdd->dd_pool; 821 uint64_t dsobj, ddobj; 822 dsl_dir_t *dd; 823 824 ASSERT(lastname[0] != '@'); 825 826 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx); 827 VERIFY(0 == dsl_dir_open_obj(dp, ddobj, lastname, FTAG, &dd)); 828 829 dsobj = dsl_dataset_create_sync_dd(dd, origin, flags, tx); 830 831 dsl_deleg_set_create_perms(dd, tx, cr); 832 833 dsl_dir_close(dd, FTAG); 834 835 return (dsobj); 836 } 837 838 struct destroyarg { 839 dsl_sync_task_group_t *dstg; 840 char *snapname; 841 char *failed; 842 }; 843 844 static int 845 dsl_snapshot_destroy_one(char *name, void *arg) 846 { 847 struct destroyarg *da = arg; 848 dsl_dataset_t *ds; 849 char *cp; 850 int err; 851 852 (void) strcat(name, "@"); 853 (void) strcat(name, da->snapname); 854 err = dsl_dataset_own(name, DS_MODE_READONLY | DS_MODE_INCONSISTENT, 855 da->dstg, &ds); 856 cp = strchr(name, '@'); 857 *cp = '\0'; 858 if (err == 0) { 859 dsl_dataset_make_exclusive(ds, da->dstg); 860 if (ds->ds_user_ptr) { 861 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 862 ds->ds_user_ptr = NULL; 863 } 864 dsl_sync_task_create(da->dstg, dsl_dataset_destroy_check, 865 dsl_dataset_destroy_sync, ds, da->dstg, 0); 866 } else if (err == ENOENT) { 867 err = 0; 868 } else { 869 (void) strcpy(da->failed, name); 870 } 871 return (err); 872 } 873 874 /* 875 * Destroy 'snapname' in all descendants of 'fsname'. 876 */ 877 #pragma weak dmu_snapshots_destroy = dsl_snapshots_destroy 878 int 879 dsl_snapshots_destroy(char *fsname, char *snapname) 880 { 881 int err; 882 struct destroyarg da; 883 dsl_sync_task_t *dst; 884 spa_t *spa; 885 886 err = spa_open(fsname, &spa, FTAG); 887 if (err) 888 return (err); 889 da.dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 890 da.snapname = snapname; 891 da.failed = fsname; 892 893 err = dmu_objset_find(fsname, 894 dsl_snapshot_destroy_one, &da, DS_FIND_CHILDREN); 895 896 if (err == 0) 897 err = dsl_sync_task_group_wait(da.dstg); 898 899 for (dst = list_head(&da.dstg->dstg_tasks); dst; 900 dst = list_next(&da.dstg->dstg_tasks, dst)) { 901 dsl_dataset_t *ds = dst->dst_arg1; 902 /* 903 * Return the file system name that triggered the error 904 */ 905 if (dst->dst_err) { 906 dsl_dataset_name(ds, fsname); 907 *strchr(fsname, '@') = '\0'; 908 } 909 dsl_dataset_disown(ds, da.dstg); 910 } 911 912 dsl_sync_task_group_destroy(da.dstg); 913 spa_close(spa, FTAG); 914 return (err); 915 } 916 917 /* 918 * ds must be opened as OWNER. On return (whether successful or not), 919 * ds will be closed and caller can no longer dereference it. 920 */ 921 int 922 dsl_dataset_destroy(dsl_dataset_t *ds, void *tag) 923 { 924 int err; 925 dsl_sync_task_group_t *dstg; 926 objset_t *os; 927 dsl_dir_t *dd; 928 uint64_t obj; 929 930 if (dsl_dataset_is_snapshot(ds)) { 931 /* Destroying a snapshot is simpler */ 932 dsl_dataset_make_exclusive(ds, tag); 933 934 if (ds->ds_user_ptr) { 935 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 936 ds->ds_user_ptr = NULL; 937 } 938 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 939 dsl_dataset_destroy_check, dsl_dataset_destroy_sync, 940 ds, tag, 0); 941 goto out; 942 } 943 944 dd = ds->ds_dir; 945 946 /* 947 * Check for errors and mark this ds as inconsistent, in 948 * case we crash while freeing the objects. 949 */ 950 err = dsl_sync_task_do(dd->dd_pool, dsl_dataset_destroy_begin_check, 951 dsl_dataset_destroy_begin_sync, ds, NULL, 0); 952 if (err) 953 goto out; 954 955 err = dmu_objset_open_ds(ds, DMU_OST_ANY, &os); 956 if (err) 957 goto out; 958 959 /* 960 * remove the objects in open context, so that we won't 961 * have too much to do in syncing context. 962 */ 963 for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 964 ds->ds_phys->ds_prev_snap_txg)) { 965 /* 966 * Ignore errors, if there is not enough disk space 967 * we will deal with it in dsl_dataset_destroy_sync(). 968 */ 969 (void) dmu_free_object(os, obj); 970 } 971 972 dmu_objset_close(os); 973 if (err != ESRCH) 974 goto out; 975 976 rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER); 977 err = dsl_dir_open_obj(dd->dd_pool, dd->dd_object, NULL, FTAG, &dd); 978 rw_exit(&dd->dd_pool->dp_config_rwlock); 979 980 if (err) 981 goto out; 982 983 if (ds->ds_user_ptr) { 984 /* 985 * We need to sync out all in-flight IO before we try 986 * to evict (the dataset evict func is trying to clear 987 * the cached entries for this dataset in the ARC). 988 */ 989 txg_wait_synced(dd->dd_pool, 0); 990 } 991 992 /* 993 * Blow away the dsl_dir + head dataset. 994 */ 995 dsl_dataset_make_exclusive(ds, tag); 996 if (ds->ds_user_ptr) { 997 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 998 ds->ds_user_ptr = NULL; 999 } 1000 dstg = dsl_sync_task_group_create(ds->ds_dir->dd_pool); 1001 dsl_sync_task_create(dstg, dsl_dataset_destroy_check, 1002 dsl_dataset_destroy_sync, ds, tag, 0); 1003 dsl_sync_task_create(dstg, dsl_dir_destroy_check, 1004 dsl_dir_destroy_sync, dd, FTAG, 0); 1005 err = dsl_sync_task_group_wait(dstg); 1006 dsl_sync_task_group_destroy(dstg); 1007 /* if it is successful, dsl_dir_destroy_sync will close the dd */ 1008 if (err) 1009 dsl_dir_close(dd, FTAG); 1010 out: 1011 dsl_dataset_disown(ds, tag); 1012 return (err); 1013 } 1014 1015 int 1016 dsl_dataset_rollback(dsl_dataset_t *ds, dmu_objset_type_t ost) 1017 { 1018 int err; 1019 1020 ASSERT(ds->ds_owner); 1021 1022 dsl_dataset_make_exclusive(ds, ds->ds_owner); 1023 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 1024 dsl_dataset_rollback_check, dsl_dataset_rollback_sync, 1025 ds, &ost, 0); 1026 /* drop exclusive access */ 1027 mutex_enter(&ds->ds_lock); 1028 rw_exit(&ds->ds_rwlock); 1029 cv_broadcast(&ds->ds_exclusive_cv); 1030 mutex_exit(&ds->ds_lock); 1031 return (err); 1032 } 1033 1034 void * 1035 dsl_dataset_set_user_ptr(dsl_dataset_t *ds, 1036 void *p, dsl_dataset_evict_func_t func) 1037 { 1038 void *old; 1039 1040 mutex_enter(&ds->ds_lock); 1041 old = ds->ds_user_ptr; 1042 if (old == NULL) { 1043 ds->ds_user_ptr = p; 1044 ds->ds_user_evict_func = func; 1045 } 1046 mutex_exit(&ds->ds_lock); 1047 return (old); 1048 } 1049 1050 void * 1051 dsl_dataset_get_user_ptr(dsl_dataset_t *ds) 1052 { 1053 return (ds->ds_user_ptr); 1054 } 1055 1056 1057 blkptr_t * 1058 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1059 { 1060 return (&ds->ds_phys->ds_bp); 1061 } 1062 1063 void 1064 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1065 { 1066 ASSERT(dmu_tx_is_syncing(tx)); 1067 /* If it's the meta-objset, set dp_meta_rootbp */ 1068 if (ds == NULL) { 1069 tx->tx_pool->dp_meta_rootbp = *bp; 1070 } else { 1071 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1072 ds->ds_phys->ds_bp = *bp; 1073 } 1074 } 1075 1076 spa_t * 1077 dsl_dataset_get_spa(dsl_dataset_t *ds) 1078 { 1079 return (ds->ds_dir->dd_pool->dp_spa); 1080 } 1081 1082 void 1083 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1084 { 1085 dsl_pool_t *dp; 1086 1087 if (ds == NULL) /* this is the meta-objset */ 1088 return; 1089 1090 ASSERT(ds->ds_user_ptr != NULL); 1091 1092 if (ds->ds_phys->ds_next_snap_obj != 0) 1093 panic("dirtying snapshot!"); 1094 1095 dp = ds->ds_dir->dd_pool; 1096 1097 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg) == 0) { 1098 /* up the hold count until we can be written out */ 1099 dmu_buf_add_ref(ds->ds_dbuf, ds); 1100 } 1101 } 1102 1103 /* 1104 * The unique space in the head dataset can be calculated by subtracting 1105 * the space used in the most recent snapshot, that is still being used 1106 * in this file system, from the space currently in use. To figure out 1107 * the space in the most recent snapshot still in use, we need to take 1108 * the total space used in the snapshot and subtract out the space that 1109 * has been freed up since the snapshot was taken. 1110 */ 1111 static void 1112 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 1113 { 1114 uint64_t mrs_used; 1115 uint64_t dlused, dlcomp, dluncomp; 1116 1117 ASSERT(ds->ds_object == ds->ds_dir->dd_phys->dd_head_dataset_obj); 1118 1119 if (ds->ds_phys->ds_prev_snap_obj != 0) 1120 mrs_used = ds->ds_prev->ds_phys->ds_used_bytes; 1121 else 1122 mrs_used = 0; 1123 1124 VERIFY(0 == bplist_space(&ds->ds_deadlist, &dlused, &dlcomp, 1125 &dluncomp)); 1126 1127 ASSERT3U(dlused, <=, mrs_used); 1128 ds->ds_phys->ds_unique_bytes = 1129 ds->ds_phys->ds_used_bytes - (mrs_used - dlused); 1130 1131 if (!DS_UNIQUE_IS_ACCURATE(ds) && 1132 spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1133 SPA_VERSION_UNIQUE_ACCURATE) 1134 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1135 } 1136 1137 static uint64_t 1138 dsl_dataset_unique(dsl_dataset_t *ds) 1139 { 1140 if (!DS_UNIQUE_IS_ACCURATE(ds) && !dsl_dataset_is_snapshot(ds)) 1141 dsl_dataset_recalc_head_uniq(ds); 1142 1143 return (ds->ds_phys->ds_unique_bytes); 1144 } 1145 1146 struct killarg { 1147 dsl_dataset_t *ds; 1148 zio_t *zio; 1149 dmu_tx_t *tx; 1150 }; 1151 1152 /* ARGSUSED */ 1153 static int 1154 kill_blkptr(traverse_blk_cache_t *bc, spa_t *spa, void *arg) 1155 { 1156 struct killarg *ka = arg; 1157 blkptr_t *bp = &bc->bc_blkptr; 1158 1159 ASSERT3U(bc->bc_errno, ==, 0); 1160 1161 ASSERT3U(bp->blk_birth, >, ka->ds->ds_phys->ds_prev_snap_txg); 1162 (void) dsl_dataset_block_kill(ka->ds, bp, ka->zio, ka->tx); 1163 1164 return (0); 1165 } 1166 1167 /* ARGSUSED */ 1168 static int 1169 dsl_dataset_rollback_check(void *arg1, void *arg2, dmu_tx_t *tx) 1170 { 1171 dsl_dataset_t *ds = arg1; 1172 dmu_objset_type_t *ost = arg2; 1173 1174 /* 1175 * We can only roll back to emptyness if it is a ZPL objset. 1176 */ 1177 if (*ost != DMU_OST_ZFS && ds->ds_phys->ds_prev_snap_txg == 0) 1178 return (EINVAL); 1179 1180 /* 1181 * This must not be a snapshot. 1182 */ 1183 if (ds->ds_phys->ds_next_snap_obj != 0) 1184 return (EINVAL); 1185 1186 /* 1187 * If we made changes this txg, traverse_dsl_dataset won't find 1188 * them. Try again. 1189 */ 1190 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1191 return (EAGAIN); 1192 1193 return (0); 1194 } 1195 1196 /* ARGSUSED */ 1197 static void 1198 dsl_dataset_rollback_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1199 { 1200 dsl_dataset_t *ds = arg1; 1201 dmu_objset_type_t *ost = arg2; 1202 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1203 1204 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1205 1206 /* 1207 * Before the roll back destroy the zil. 1208 */ 1209 if (ds->ds_user_ptr != NULL) { 1210 zil_rollback_destroy( 1211 ((objset_impl_t *)ds->ds_user_ptr)->os_zil, tx); 1212 1213 /* 1214 * We need to make sure that the objset_impl_t is reopened after 1215 * we do the rollback, otherwise it will have the wrong 1216 * objset_phys_t. Normally this would happen when this 1217 * dataset-open is closed, thus causing the 1218 * dataset to be immediately evicted. But when doing "zfs recv 1219 * -F", we reopen the objset before that, so that there is no 1220 * window where the dataset is closed and inconsistent. 1221 */ 1222 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1223 ds->ds_user_ptr = NULL; 1224 } 1225 1226 /* Transfer space that was freed since last snap back to the head. */ 1227 { 1228 uint64_t used; 1229 1230 VERIFY(0 == bplist_space_birthrange(&ds->ds_deadlist, 1231 ds->ds_origin_txg, UINT64_MAX, &used)); 1232 dsl_dir_transfer_space(ds->ds_dir, used, 1233 DD_USED_SNAP, DD_USED_HEAD, tx); 1234 } 1235 1236 /* Zero out the deadlist. */ 1237 bplist_close(&ds->ds_deadlist); 1238 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1239 ds->ds_phys->ds_deadlist_obj = 1240 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1241 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1242 ds->ds_phys->ds_deadlist_obj)); 1243 1244 { 1245 /* Free blkptrs that we gave birth to */ 1246 zio_t *zio; 1247 struct killarg ka; 1248 1249 zio = zio_root(tx->tx_pool->dp_spa, NULL, NULL, 1250 ZIO_FLAG_MUSTSUCCEED); 1251 ka.ds = ds; 1252 ka.zio = zio; 1253 ka.tx = tx; 1254 (void) traverse_dsl_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1255 ADVANCE_POST, kill_blkptr, &ka); 1256 (void) zio_wait(zio); 1257 } 1258 1259 ASSERT(!(ds->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) || 1260 ds->ds_phys->ds_unique_bytes == 0); 1261 1262 if (ds->ds_prev && ds->ds_prev != ds->ds_dir->dd_pool->dp_origin_snap) { 1263 /* Change our contents to that of the prev snapshot */ 1264 1265 ASSERT3U(ds->ds_prev->ds_object, ==, 1266 ds->ds_phys->ds_prev_snap_obj); 1267 ASSERT3U(ds->ds_phys->ds_used_bytes, <=, 1268 ds->ds_prev->ds_phys->ds_used_bytes); 1269 1270 ds->ds_phys->ds_bp = ds->ds_prev->ds_phys->ds_bp; 1271 ds->ds_phys->ds_used_bytes = 1272 ds->ds_prev->ds_phys->ds_used_bytes; 1273 ds->ds_phys->ds_compressed_bytes = 1274 ds->ds_prev->ds_phys->ds_compressed_bytes; 1275 ds->ds_phys->ds_uncompressed_bytes = 1276 ds->ds_prev->ds_phys->ds_uncompressed_bytes; 1277 ds->ds_phys->ds_flags = ds->ds_prev->ds_phys->ds_flags; 1278 1279 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1280 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1281 ds->ds_prev->ds_phys->ds_unique_bytes = 0; 1282 } 1283 } else { 1284 objset_impl_t *osi; 1285 1286 ASSERT3U(ds->ds_phys->ds_used_bytes, ==, 0); 1287 ASSERT3U(ds->ds_phys->ds_compressed_bytes, ==, 0); 1288 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, ==, 0); 1289 1290 bzero(&ds->ds_phys->ds_bp, sizeof (blkptr_t)); 1291 ds->ds_phys->ds_flags = 0; 1292 ds->ds_phys->ds_unique_bytes = 0; 1293 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1294 SPA_VERSION_UNIQUE_ACCURATE) 1295 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1296 1297 osi = dmu_objset_create_impl(ds->ds_dir->dd_pool->dp_spa, ds, 1298 &ds->ds_phys->ds_bp, *ost, tx); 1299 #ifdef _KERNEL 1300 zfs_create_fs(&osi->os, kcred, NULL, tx); 1301 #endif 1302 } 1303 1304 spa_history_internal_log(LOG_DS_ROLLBACK, ds->ds_dir->dd_pool->dp_spa, 1305 tx, cr, "dataset = %llu", ds->ds_object); 1306 } 1307 1308 /* ARGSUSED */ 1309 static int 1310 dsl_dataset_destroy_begin_check(void *arg1, void *arg2, dmu_tx_t *tx) 1311 { 1312 dsl_dataset_t *ds = arg1; 1313 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1314 uint64_t count; 1315 int err; 1316 1317 /* 1318 * Can't delete a head dataset if there are snapshots of it. 1319 * (Except if the only snapshots are from the branch we cloned 1320 * from.) 1321 */ 1322 if (ds->ds_prev != NULL && 1323 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1324 return (EINVAL); 1325 1326 /* 1327 * This is really a dsl_dir thing, but check it here so that 1328 * we'll be less likely to leave this dataset inconsistent & 1329 * nearly destroyed. 1330 */ 1331 err = zap_count(mos, ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count); 1332 if (err) 1333 return (err); 1334 if (count != 0) 1335 return (EEXIST); 1336 1337 return (0); 1338 } 1339 1340 /* ARGSUSED */ 1341 static void 1342 dsl_dataset_destroy_begin_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1343 { 1344 dsl_dataset_t *ds = arg1; 1345 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1346 1347 /* Mark it as inconsistent on-disk, in case we crash */ 1348 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1349 ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT; 1350 1351 spa_history_internal_log(LOG_DS_DESTROY_BEGIN, dp->dp_spa, tx, 1352 cr, "dataset = %llu", ds->ds_object); 1353 } 1354 1355 /* ARGSUSED */ 1356 int 1357 dsl_dataset_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx) 1358 { 1359 dsl_dataset_t *ds = arg1; 1360 1361 /* we have an owner hold, so noone else can destroy us */ 1362 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 1363 1364 /* Can't delete a branch point. */ 1365 if (ds->ds_phys->ds_num_children > 1) 1366 return (EEXIST); 1367 1368 /* 1369 * Can't delete a head dataset if there are snapshots of it. 1370 * (Except if the only snapshots are from the branch we cloned 1371 * from.) 1372 */ 1373 if (ds->ds_prev != NULL && 1374 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1375 return (EINVAL); 1376 1377 /* 1378 * If we made changes this txg, traverse_dsl_dataset won't find 1379 * them. Try again. 1380 */ 1381 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1382 return (EAGAIN); 1383 1384 /* XXX we should do some i/o error checking... */ 1385 return (0); 1386 } 1387 1388 struct refsarg { 1389 kmutex_t lock; 1390 boolean_t gone; 1391 kcondvar_t cv; 1392 }; 1393 1394 /* ARGSUSED */ 1395 static void 1396 dsl_dataset_refs_gone(dmu_buf_t *db, void *argv) 1397 { 1398 struct refsarg *arg = argv; 1399 1400 mutex_enter(&arg->lock); 1401 arg->gone = TRUE; 1402 cv_signal(&arg->cv); 1403 mutex_exit(&arg->lock); 1404 } 1405 1406 static void 1407 dsl_dataset_drain_refs(dsl_dataset_t *ds, void *tag) 1408 { 1409 struct refsarg arg; 1410 1411 mutex_init(&arg.lock, NULL, MUTEX_DEFAULT, NULL); 1412 cv_init(&arg.cv, NULL, CV_DEFAULT, NULL); 1413 arg.gone = FALSE; 1414 (void) dmu_buf_update_user(ds->ds_dbuf, ds, &arg, &ds->ds_phys, 1415 dsl_dataset_refs_gone); 1416 dmu_buf_rele(ds->ds_dbuf, tag); 1417 mutex_enter(&arg.lock); 1418 while (!arg.gone) 1419 cv_wait(&arg.cv, &arg.lock); 1420 ASSERT(arg.gone); 1421 mutex_exit(&arg.lock); 1422 ds->ds_dbuf = NULL; 1423 ds->ds_phys = NULL; 1424 mutex_destroy(&arg.lock); 1425 cv_destroy(&arg.cv); 1426 } 1427 1428 void 1429 dsl_dataset_destroy_sync(void *arg1, void *tag, cred_t *cr, dmu_tx_t *tx) 1430 { 1431 dsl_dataset_t *ds = arg1; 1432 zio_t *zio; 1433 int err; 1434 int after_branch_point = FALSE; 1435 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1436 objset_t *mos = dp->dp_meta_objset; 1437 dsl_dataset_t *ds_prev = NULL; 1438 uint64_t obj; 1439 1440 ASSERT(ds->ds_owner); 1441 ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); 1442 ASSERT(ds->ds_prev == NULL || 1443 ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object); 1444 ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); 1445 1446 /* signal any waiters that this dataset is going away */ 1447 mutex_enter(&ds->ds_lock); 1448 ds->ds_owner = dsl_reaper; 1449 cv_broadcast(&ds->ds_exclusive_cv); 1450 mutex_exit(&ds->ds_lock); 1451 1452 /* Remove our reservation */ 1453 if (ds->ds_reserved != 0) { 1454 uint64_t val = 0; 1455 dsl_dataset_set_reservation_sync(ds, &val, cr, tx); 1456 ASSERT3U(ds->ds_reserved, ==, 0); 1457 } 1458 1459 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1460 1461 dsl_pool_ds_destroyed(ds, tx); 1462 1463 obj = ds->ds_object; 1464 1465 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1466 if (ds->ds_prev) { 1467 ds_prev = ds->ds_prev; 1468 } else { 1469 VERIFY(0 == dsl_dataset_hold_obj(dp, 1470 ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev)); 1471 } 1472 after_branch_point = 1473 (ds_prev->ds_phys->ds_next_snap_obj != obj); 1474 1475 dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); 1476 if (after_branch_point && 1477 ds_prev->ds_phys->ds_next_clones_obj != 0) { 1478 VERIFY(0 == zap_remove_int(mos, 1479 ds_prev->ds_phys->ds_next_clones_obj, obj, tx)); 1480 if (ds->ds_phys->ds_next_snap_obj != 0) { 1481 VERIFY(0 == zap_add_int(mos, 1482 ds_prev->ds_phys->ds_next_clones_obj, 1483 ds->ds_phys->ds_next_snap_obj, tx)); 1484 } 1485 } 1486 if (after_branch_point && 1487 ds->ds_phys->ds_next_snap_obj == 0) { 1488 /* This clone is toast. */ 1489 ASSERT(ds_prev->ds_phys->ds_num_children > 1); 1490 ds_prev->ds_phys->ds_num_children--; 1491 } else if (!after_branch_point) { 1492 ds_prev->ds_phys->ds_next_snap_obj = 1493 ds->ds_phys->ds_next_snap_obj; 1494 } 1495 } 1496 1497 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 1498 1499 if (ds->ds_phys->ds_next_snap_obj != 0) { 1500 blkptr_t bp; 1501 dsl_dataset_t *ds_next; 1502 uint64_t itor = 0; 1503 uint64_t old_unique; 1504 int64_t used = 0, compressed = 0, uncompressed = 0; 1505 1506 VERIFY(0 == dsl_dataset_hold_obj(dp, 1507 ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next)); 1508 ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj); 1509 1510 old_unique = dsl_dataset_unique(ds_next); 1511 1512 dmu_buf_will_dirty(ds_next->ds_dbuf, tx); 1513 ds_next->ds_phys->ds_prev_snap_obj = 1514 ds->ds_phys->ds_prev_snap_obj; 1515 ds_next->ds_phys->ds_prev_snap_txg = 1516 ds->ds_phys->ds_prev_snap_txg; 1517 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1518 ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0); 1519 1520 /* 1521 * Transfer to our deadlist (which will become next's 1522 * new deadlist) any entries from next's current 1523 * deadlist which were born before prev, and free the 1524 * other entries. 1525 * 1526 * XXX we're doing this long task with the config lock held 1527 */ 1528 while (bplist_iterate(&ds_next->ds_deadlist, &itor, &bp) == 0) { 1529 if (bp.blk_birth <= ds->ds_phys->ds_prev_snap_txg) { 1530 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, 1531 &bp, tx)); 1532 if (ds_prev && !after_branch_point && 1533 bp.blk_birth > 1534 ds_prev->ds_phys->ds_prev_snap_txg) { 1535 ds_prev->ds_phys->ds_unique_bytes += 1536 bp_get_dasize(dp->dp_spa, &bp); 1537 } 1538 } else { 1539 used += bp_get_dasize(dp->dp_spa, &bp); 1540 compressed += BP_GET_PSIZE(&bp); 1541 uncompressed += BP_GET_UCSIZE(&bp); 1542 /* XXX check return value? */ 1543 (void) dsl_free(zio, dp, tx->tx_txg, 1544 &bp, NULL, NULL, ARC_NOWAIT); 1545 } 1546 } 1547 1548 ASSERT3U(used, ==, ds->ds_phys->ds_unique_bytes); 1549 1550 /* change snapused */ 1551 dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP, 1552 -used, -compressed, -uncompressed, tx); 1553 1554 /* free next's deadlist */ 1555 bplist_close(&ds_next->ds_deadlist); 1556 bplist_destroy(mos, ds_next->ds_phys->ds_deadlist_obj, tx); 1557 1558 /* set next's deadlist to our deadlist */ 1559 bplist_close(&ds->ds_deadlist); 1560 ds_next->ds_phys->ds_deadlist_obj = 1561 ds->ds_phys->ds_deadlist_obj; 1562 VERIFY(0 == bplist_open(&ds_next->ds_deadlist, mos, 1563 ds_next->ds_phys->ds_deadlist_obj)); 1564 ds->ds_phys->ds_deadlist_obj = 0; 1565 1566 if (ds_next->ds_phys->ds_next_snap_obj != 0) { 1567 /* 1568 * Update next's unique to include blocks which 1569 * were previously shared by only this snapshot 1570 * and it. Those blocks will be born after the 1571 * prev snap and before this snap, and will have 1572 * died after the next snap and before the one 1573 * after that (ie. be on the snap after next's 1574 * deadlist). 1575 * 1576 * XXX we're doing this long task with the 1577 * config lock held 1578 */ 1579 dsl_dataset_t *ds_after_next; 1580 uint64_t space; 1581 1582 VERIFY(0 == dsl_dataset_hold_obj(dp, 1583 ds_next->ds_phys->ds_next_snap_obj, 1584 FTAG, &ds_after_next)); 1585 1586 VERIFY(0 == 1587 bplist_space_birthrange(&ds_after_next->ds_deadlist, 1588 ds->ds_phys->ds_prev_snap_txg, 1589 ds->ds_phys->ds_creation_txg, &space)); 1590 ds_next->ds_phys->ds_unique_bytes += space; 1591 1592 dsl_dataset_rele(ds_after_next, FTAG); 1593 ASSERT3P(ds_next->ds_prev, ==, NULL); 1594 } else { 1595 ASSERT3P(ds_next->ds_prev, ==, ds); 1596 dsl_dataset_drop_ref(ds_next->ds_prev, ds_next); 1597 ds_next->ds_prev = NULL; 1598 if (ds_prev) { 1599 VERIFY(0 == dsl_dataset_get_ref(dp, 1600 ds->ds_phys->ds_prev_snap_obj, 1601 ds_next, &ds_next->ds_prev)); 1602 } 1603 1604 dsl_dataset_recalc_head_uniq(ds_next); 1605 1606 /* 1607 * Reduce the amount of our unconsmed refreservation 1608 * being charged to our parent by the amount of 1609 * new unique data we have gained. 1610 */ 1611 if (old_unique < ds_next->ds_reserved) { 1612 int64_t mrsdelta; 1613 uint64_t new_unique = 1614 ds_next->ds_phys->ds_unique_bytes; 1615 1616 ASSERT(old_unique <= new_unique); 1617 mrsdelta = MIN(new_unique - old_unique, 1618 ds_next->ds_reserved - old_unique); 1619 dsl_dir_diduse_space(ds->ds_dir, 1620 DD_USED_REFRSRV, -mrsdelta, 0, 0, tx); 1621 } 1622 } 1623 dsl_dataset_rele(ds_next, FTAG); 1624 } else { 1625 /* 1626 * There's no next snapshot, so this is a head dataset. 1627 * Destroy the deadlist. Unless it's a clone, the 1628 * deadlist should be empty. (If it's a clone, it's 1629 * safe to ignore the deadlist contents.) 1630 */ 1631 struct killarg ka; 1632 1633 ASSERT(after_branch_point || bplist_empty(&ds->ds_deadlist)); 1634 bplist_close(&ds->ds_deadlist); 1635 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1636 ds->ds_phys->ds_deadlist_obj = 0; 1637 1638 /* 1639 * Free everything that we point to (that's born after 1640 * the previous snapshot, if we are a clone) 1641 * 1642 * NB: this should be very quick, because we already 1643 * freed all the objects in open context. 1644 */ 1645 ka.ds = ds; 1646 ka.zio = zio; 1647 ka.tx = tx; 1648 err = traverse_dsl_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1649 ADVANCE_POST, kill_blkptr, &ka); 1650 ASSERT3U(err, ==, 0); 1651 ASSERT(spa_version(dp->dp_spa) < SPA_VERSION_UNIQUE_ACCURATE || 1652 ds->ds_phys->ds_unique_bytes == 0); 1653 } 1654 1655 err = zio_wait(zio); 1656 ASSERT3U(err, ==, 0); 1657 1658 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == ds->ds_object) { 1659 /* Erase the link in the dir */ 1660 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); 1661 ds->ds_dir->dd_phys->dd_head_dataset_obj = 0; 1662 ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0); 1663 err = zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx); 1664 ASSERT(err == 0); 1665 } else { 1666 /* remove from snapshot namespace */ 1667 dsl_dataset_t *ds_head; 1668 ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0); 1669 VERIFY(0 == dsl_dataset_hold_obj(dp, 1670 ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head)); 1671 VERIFY(0 == dsl_dataset_get_snapname(ds)); 1672 #ifdef ZFS_DEBUG 1673 { 1674 uint64_t val; 1675 1676 err = dsl_dataset_snap_lookup(ds_head, 1677 ds->ds_snapname, &val); 1678 ASSERT3U(err, ==, 0); 1679 ASSERT3U(val, ==, obj); 1680 } 1681 #endif 1682 err = dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx); 1683 ASSERT(err == 0); 1684 dsl_dataset_rele(ds_head, FTAG); 1685 } 1686 1687 if (ds_prev && ds->ds_prev != ds_prev) 1688 dsl_dataset_rele(ds_prev, FTAG); 1689 1690 spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); 1691 spa_history_internal_log(LOG_DS_DESTROY, dp->dp_spa, tx, 1692 cr, "dataset = %llu", ds->ds_object); 1693 1694 if (ds->ds_phys->ds_next_clones_obj != 0) { 1695 uint64_t count; 1696 ASSERT(0 == zap_count(mos, 1697 ds->ds_phys->ds_next_clones_obj, &count) && count == 0); 1698 VERIFY(0 == dmu_object_free(mos, 1699 ds->ds_phys->ds_next_clones_obj, tx)); 1700 } 1701 if (ds->ds_phys->ds_props_obj != 0) 1702 VERIFY(0 == zap_destroy(mos, ds->ds_phys->ds_props_obj, tx)); 1703 dsl_dir_close(ds->ds_dir, ds); 1704 ds->ds_dir = NULL; 1705 dsl_dataset_drain_refs(ds, tag); 1706 VERIFY(0 == dmu_object_free(mos, obj, tx)); 1707 } 1708 1709 static int 1710 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1711 { 1712 uint64_t asize; 1713 1714 if (!dmu_tx_is_syncing(tx)) 1715 return (0); 1716 1717 /* 1718 * If there's an fs-only reservation, any blocks that might become 1719 * owned by the snapshot dataset must be accommodated by space 1720 * outside of the reservation. 1721 */ 1722 asize = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1723 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, FALSE)) 1724 return (ENOSPC); 1725 1726 /* 1727 * Propogate any reserved space for this snapshot to other 1728 * snapshot checks in this sync group. 1729 */ 1730 if (asize > 0) 1731 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1732 1733 return (0); 1734 } 1735 1736 /* ARGSUSED */ 1737 int 1738 dsl_dataset_snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx) 1739 { 1740 dsl_dataset_t *ds = arg1; 1741 const char *snapname = arg2; 1742 int err; 1743 uint64_t value; 1744 1745 /* 1746 * We don't allow multiple snapshots of the same txg. If there 1747 * is already one, try again. 1748 */ 1749 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 1750 return (EAGAIN); 1751 1752 /* 1753 * Check for conflicting name snapshot name. 1754 */ 1755 err = dsl_dataset_snap_lookup(ds, snapname, &value); 1756 if (err == 0) 1757 return (EEXIST); 1758 if (err != ENOENT) 1759 return (err); 1760 1761 /* 1762 * Check that the dataset's name is not too long. Name consists 1763 * of the dataset's length + 1 for the @-sign + snapshot name's length 1764 */ 1765 if (dsl_dataset_namelen(ds) + 1 + strlen(snapname) >= MAXNAMELEN) 1766 return (ENAMETOOLONG); 1767 1768 err = dsl_dataset_snapshot_reserve_space(ds, tx); 1769 if (err) 1770 return (err); 1771 1772 ds->ds_trysnap_txg = tx->tx_txg; 1773 return (0); 1774 } 1775 1776 void 1777 dsl_dataset_snapshot_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1778 { 1779 dsl_dataset_t *ds = arg1; 1780 const char *snapname = arg2; 1781 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1782 dmu_buf_t *dbuf; 1783 dsl_dataset_phys_t *dsphys; 1784 uint64_t dsobj, crtxg; 1785 objset_t *mos = dp->dp_meta_objset; 1786 int err; 1787 1788 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1789 1790 /* 1791 * The origin's ds_creation_txg has to be < TXG_INITIAL 1792 */ 1793 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0) 1794 crtxg = 1; 1795 else 1796 crtxg = tx->tx_txg; 1797 1798 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1799 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1800 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1801 dmu_buf_will_dirty(dbuf, tx); 1802 dsphys = dbuf->db_data; 1803 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1804 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1805 dsphys->ds_fsid_guid = unique_create(); 1806 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1807 sizeof (dsphys->ds_guid)); 1808 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1809 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1810 dsphys->ds_next_snap_obj = ds->ds_object; 1811 dsphys->ds_num_children = 1; 1812 dsphys->ds_creation_time = gethrestime_sec(); 1813 dsphys->ds_creation_txg = crtxg; 1814 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1815 dsphys->ds_used_bytes = ds->ds_phys->ds_used_bytes; 1816 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1817 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1818 dsphys->ds_flags = ds->ds_phys->ds_flags; 1819 dsphys->ds_bp = ds->ds_phys->ds_bp; 1820 dmu_buf_rele(dbuf, FTAG); 1821 1822 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1823 if (ds->ds_prev) { 1824 uint64_t next_clones_obj = 1825 ds->ds_prev->ds_phys->ds_next_clones_obj; 1826 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1827 ds->ds_object || 1828 ds->ds_prev->ds_phys->ds_num_children > 1); 1829 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1830 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1831 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1832 ds->ds_prev->ds_phys->ds_creation_txg); 1833 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1834 } else if (next_clones_obj != 0) { 1835 VERIFY3U(0, ==, zap_remove_int(mos, 1836 next_clones_obj, dsphys->ds_next_snap_obj, tx)); 1837 VERIFY3U(0, ==, zap_add_int(mos, 1838 next_clones_obj, dsobj, tx)); 1839 } 1840 } 1841 1842 /* 1843 * If we have a reference-reservation on this dataset, we will 1844 * need to increase the amount of refreservation being charged 1845 * since our unique space is going to zero. 1846 */ 1847 if (ds->ds_reserved) { 1848 int64_t add = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1849 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, 1850 add, 0, 0, tx); 1851 } 1852 1853 bplist_close(&ds->ds_deadlist); 1854 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1855 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1856 ds->ds_phys->ds_prev_snap_obj = dsobj; 1857 ds->ds_phys->ds_prev_snap_txg = crtxg; 1858 ds->ds_phys->ds_unique_bytes = 0; 1859 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1860 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1861 ds->ds_phys->ds_deadlist_obj = 1862 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1863 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1864 ds->ds_phys->ds_deadlist_obj)); 1865 1866 dprintf("snap '%s' -> obj %llu\n", snapname, dsobj); 1867 err = zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1868 snapname, 8, 1, &dsobj, tx); 1869 ASSERT(err == 0); 1870 1871 if (ds->ds_prev) 1872 dsl_dataset_drop_ref(ds->ds_prev, ds); 1873 VERIFY(0 == dsl_dataset_get_ref(dp, 1874 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1875 1876 dsl_pool_ds_snapshotted(ds, tx); 1877 1878 spa_history_internal_log(LOG_DS_SNAPSHOT, dp->dp_spa, tx, cr, 1879 "dataset = %llu", dsobj); 1880 } 1881 1882 void 1883 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1884 { 1885 ASSERT(dmu_tx_is_syncing(tx)); 1886 ASSERT(ds->ds_user_ptr != NULL); 1887 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1888 1889 /* 1890 * in case we had to change ds_fsid_guid when we opened it, 1891 * sync it out now. 1892 */ 1893 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1894 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1895 1896 dsl_dir_dirty(ds->ds_dir, tx); 1897 dmu_objset_sync(ds->ds_user_ptr, zio, tx); 1898 } 1899 1900 void 1901 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1902 { 1903 uint64_t refd, avail, uobjs, aobjs; 1904 1905 dsl_dir_stats(ds->ds_dir, nv); 1906 1907 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1908 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1909 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1910 1911 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1912 ds->ds_phys->ds_creation_time); 1913 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1914 ds->ds_phys->ds_creation_txg); 1915 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1916 ds->ds_quota); 1917 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1918 ds->ds_reserved); 1919 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1920 ds->ds_phys->ds_guid); 1921 1922 if (ds->ds_phys->ds_next_snap_obj) { 1923 /* 1924 * This is a snapshot; override the dd's space used with 1925 * our unique space and compression ratio. 1926 */ 1927 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1928 ds->ds_phys->ds_unique_bytes); 1929 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, 1930 ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1931 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1932 ds->ds_phys->ds_compressed_bytes)); 1933 } 1934 } 1935 1936 void 1937 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1938 { 1939 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1940 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1941 stat->dds_guid = ds->ds_phys->ds_guid; 1942 if (ds->ds_phys->ds_next_snap_obj) { 1943 stat->dds_is_snapshot = B_TRUE; 1944 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1945 } 1946 1947 /* clone origin is really a dsl_dir thing... */ 1948 rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER); 1949 if (dsl_dir_is_clone(ds->ds_dir)) { 1950 dsl_dataset_t *ods; 1951 1952 VERIFY(0 == dsl_dataset_get_ref(ds->ds_dir->dd_pool, 1953 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1954 dsl_dataset_name(ods, stat->dds_origin); 1955 dsl_dataset_drop_ref(ods, FTAG); 1956 } 1957 rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock); 1958 } 1959 1960 uint64_t 1961 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1962 { 1963 return (ds->ds_fsid_guid); 1964 } 1965 1966 void 1967 dsl_dataset_space(dsl_dataset_t *ds, 1968 uint64_t *refdbytesp, uint64_t *availbytesp, 1969 uint64_t *usedobjsp, uint64_t *availobjsp) 1970 { 1971 *refdbytesp = ds->ds_phys->ds_used_bytes; 1972 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1973 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1974 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1975 if (ds->ds_quota != 0) { 1976 /* 1977 * Adjust available bytes according to refquota 1978 */ 1979 if (*refdbytesp < ds->ds_quota) 1980 *availbytesp = MIN(*availbytesp, 1981 ds->ds_quota - *refdbytesp); 1982 else 1983 *availbytesp = 0; 1984 } 1985 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1986 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1987 } 1988 1989 boolean_t 1990 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds) 1991 { 1992 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1993 1994 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 1995 dsl_pool_sync_context(dp)); 1996 if (ds->ds_prev == NULL) 1997 return (B_FALSE); 1998 if (ds->ds_phys->ds_bp.blk_birth > 1999 ds->ds_prev->ds_phys->ds_creation_txg) 2000 return (B_TRUE); 2001 return (B_FALSE); 2002 } 2003 2004 /* ARGSUSED */ 2005 static int 2006 dsl_dataset_snapshot_rename_check(void *arg1, void *arg2, dmu_tx_t *tx) 2007 { 2008 dsl_dataset_t *ds = arg1; 2009 char *newsnapname = arg2; 2010 dsl_dir_t *dd = ds->ds_dir; 2011 dsl_dataset_t *hds; 2012 uint64_t val; 2013 int err; 2014 2015 err = dsl_dataset_hold_obj(dd->dd_pool, 2016 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds); 2017 if (err) 2018 return (err); 2019 2020 /* new name better not be in use */ 2021 err = dsl_dataset_snap_lookup(hds, newsnapname, &val); 2022 dsl_dataset_rele(hds, FTAG); 2023 2024 if (err == 0) 2025 err = EEXIST; 2026 else if (err == ENOENT) 2027 err = 0; 2028 2029 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 2030 if (dsl_dir_namelen(ds->ds_dir) + 1 + strlen(newsnapname) >= MAXNAMELEN) 2031 err = ENAMETOOLONG; 2032 2033 return (err); 2034 } 2035 2036 static void 2037 dsl_dataset_snapshot_rename_sync(void *arg1, void *arg2, 2038 cred_t *cr, dmu_tx_t *tx) 2039 { 2040 dsl_dataset_t *ds = arg1; 2041 const char *newsnapname = arg2; 2042 dsl_dir_t *dd = ds->ds_dir; 2043 objset_t *mos = dd->dd_pool->dp_meta_objset; 2044 dsl_dataset_t *hds; 2045 int err; 2046 2047 ASSERT(ds->ds_phys->ds_next_snap_obj != 0); 2048 2049 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, 2050 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds)); 2051 2052 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2053 err = dsl_dataset_snap_remove(hds, ds->ds_snapname, tx); 2054 ASSERT3U(err, ==, 0); 2055 mutex_enter(&ds->ds_lock); 2056 (void) strcpy(ds->ds_snapname, newsnapname); 2057 mutex_exit(&ds->ds_lock); 2058 err = zap_add(mos, hds->ds_phys->ds_snapnames_zapobj, 2059 ds->ds_snapname, 8, 1, &ds->ds_object, tx); 2060 ASSERT3U(err, ==, 0); 2061 2062 spa_history_internal_log(LOG_DS_RENAME, dd->dd_pool->dp_spa, tx, 2063 cr, "dataset = %llu", ds->ds_object); 2064 dsl_dataset_rele(hds, FTAG); 2065 } 2066 2067 struct renamesnaparg { 2068 dsl_sync_task_group_t *dstg; 2069 char failed[MAXPATHLEN]; 2070 char *oldsnap; 2071 char *newsnap; 2072 }; 2073 2074 static int 2075 dsl_snapshot_rename_one(char *name, void *arg) 2076 { 2077 struct renamesnaparg *ra = arg; 2078 dsl_dataset_t *ds = NULL; 2079 char *cp; 2080 int err; 2081 2082 cp = name + strlen(name); 2083 *cp = '@'; 2084 (void) strcpy(cp + 1, ra->oldsnap); 2085 2086 /* 2087 * For recursive snapshot renames the parent won't be changing 2088 * so we just pass name for both the to/from argument. 2089 */ 2090 err = zfs_secpolicy_rename_perms(name, name, CRED()); 2091 if (err == ENOENT) { 2092 return (0); 2093 } else if (err) { 2094 (void) strcpy(ra->failed, name); 2095 return (err); 2096 } 2097 2098 #ifdef _KERNEL 2099 /* 2100 * For all filesystems undergoing rename, we'll need to unmount it. 2101 */ 2102 (void) zfs_unmount_snap(name, NULL); 2103 #endif 2104 err = dsl_dataset_hold(name, ra->dstg, &ds); 2105 *cp = '\0'; 2106 if (err == ENOENT) { 2107 return (0); 2108 } else if (err) { 2109 (void) strcpy(ra->failed, name); 2110 return (err); 2111 } 2112 2113 dsl_sync_task_create(ra->dstg, dsl_dataset_snapshot_rename_check, 2114 dsl_dataset_snapshot_rename_sync, ds, ra->newsnap, 0); 2115 2116 return (0); 2117 } 2118 2119 static int 2120 dsl_recursive_rename(char *oldname, const char *newname) 2121 { 2122 int err; 2123 struct renamesnaparg *ra; 2124 dsl_sync_task_t *dst; 2125 spa_t *spa; 2126 char *cp, *fsname = spa_strdup(oldname); 2127 int len = strlen(oldname); 2128 2129 /* truncate the snapshot name to get the fsname */ 2130 cp = strchr(fsname, '@'); 2131 *cp = '\0'; 2132 2133 err = spa_open(fsname, &spa, FTAG); 2134 if (err) { 2135 kmem_free(fsname, len + 1); 2136 return (err); 2137 } 2138 ra = kmem_alloc(sizeof (struct renamesnaparg), KM_SLEEP); 2139 ra->dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 2140 2141 ra->oldsnap = strchr(oldname, '@') + 1; 2142 ra->newsnap = strchr(newname, '@') + 1; 2143 *ra->failed = '\0'; 2144 2145 err = dmu_objset_find(fsname, dsl_snapshot_rename_one, ra, 2146 DS_FIND_CHILDREN); 2147 kmem_free(fsname, len + 1); 2148 2149 if (err == 0) { 2150 err = dsl_sync_task_group_wait(ra->dstg); 2151 } 2152 2153 for (dst = list_head(&ra->dstg->dstg_tasks); dst; 2154 dst = list_next(&ra->dstg->dstg_tasks, dst)) { 2155 dsl_dataset_t *ds = dst->dst_arg1; 2156 if (dst->dst_err) { 2157 dsl_dir_name(ds->ds_dir, ra->failed); 2158 (void) strcat(ra->failed, "@"); 2159 (void) strcat(ra->failed, ra->newsnap); 2160 } 2161 dsl_dataset_rele(ds, ra->dstg); 2162 } 2163 2164 if (err) 2165 (void) strcpy(oldname, ra->failed); 2166 2167 dsl_sync_task_group_destroy(ra->dstg); 2168 kmem_free(ra, sizeof (struct renamesnaparg)); 2169 spa_close(spa, FTAG); 2170 return (err); 2171 } 2172 2173 static int 2174 dsl_valid_rename(char *oldname, void *arg) 2175 { 2176 int delta = *(int *)arg; 2177 2178 if (strlen(oldname) + delta >= MAXNAMELEN) 2179 return (ENAMETOOLONG); 2180 2181 return (0); 2182 } 2183 2184 #pragma weak dmu_objset_rename = dsl_dataset_rename 2185 int 2186 dsl_dataset_rename(char *oldname, const char *newname, boolean_t recursive) 2187 { 2188 dsl_dir_t *dd; 2189 dsl_dataset_t *ds; 2190 const char *tail; 2191 int err; 2192 2193 err = dsl_dir_open(oldname, FTAG, &dd, &tail); 2194 if (err) 2195 return (err); 2196 if (tail == NULL) { 2197 int delta = strlen(newname) - strlen(oldname); 2198 2199 /* if we're growing, validate child name lengths */ 2200 if (delta > 0) 2201 err = dmu_objset_find(oldname, dsl_valid_rename, 2202 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS); 2203 2204 if (!err) 2205 err = dsl_dir_rename(dd, newname); 2206 dsl_dir_close(dd, FTAG); 2207 return (err); 2208 } 2209 if (tail[0] != '@') { 2210 /* the name ended in a nonexistant component */ 2211 dsl_dir_close(dd, FTAG); 2212 return (ENOENT); 2213 } 2214 2215 dsl_dir_close(dd, FTAG); 2216 2217 /* new name must be snapshot in same filesystem */ 2218 tail = strchr(newname, '@'); 2219 if (tail == NULL) 2220 return (EINVAL); 2221 tail++; 2222 if (strncmp(oldname, newname, tail - newname) != 0) 2223 return (EXDEV); 2224 2225 if (recursive) { 2226 err = dsl_recursive_rename(oldname, newname); 2227 } else { 2228 err = dsl_dataset_hold(oldname, FTAG, &ds); 2229 if (err) 2230 return (err); 2231 2232 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2233 dsl_dataset_snapshot_rename_check, 2234 dsl_dataset_snapshot_rename_sync, ds, (char *)tail, 1); 2235 2236 dsl_dataset_rele(ds, FTAG); 2237 } 2238 2239 return (err); 2240 } 2241 2242 struct promotenode { 2243 list_node_t link; 2244 dsl_dataset_t *ds; 2245 }; 2246 2247 struct promotearg { 2248 list_t shared_snaps, origin_snaps, clone_snaps; 2249 dsl_dataset_t *origin_origin, *origin_head; 2250 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap; 2251 }; 2252 2253 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep); 2254 2255 /* ARGSUSED */ 2256 static int 2257 dsl_dataset_promote_check(void *arg1, void *arg2, dmu_tx_t *tx) 2258 { 2259 dsl_dataset_t *hds = arg1; 2260 struct promotearg *pa = arg2; 2261 struct promotenode *snap = list_head(&pa->shared_snaps); 2262 dsl_dataset_t *origin_ds = snap->ds; 2263 int err; 2264 2265 /* Check that it is a real clone */ 2266 if (!dsl_dir_is_clone(hds->ds_dir)) 2267 return (EINVAL); 2268 2269 /* Since this is so expensive, don't do the preliminary check */ 2270 if (!dmu_tx_is_syncing(tx)) 2271 return (0); 2272 2273 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) 2274 return (EXDEV); 2275 2276 /* compute origin's new unique space */ 2277 snap = list_tail(&pa->clone_snaps); 2278 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2279 err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2280 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, &pa->unique); 2281 if (err) 2282 return (err); 2283 2284 /* 2285 * Walk the snapshots that we are moving 2286 * 2287 * Compute space to transfer. Consider the incremental changes 2288 * to used for each snapshot: 2289 * (my used) = (prev's used) + (blocks born) - (blocks killed) 2290 * So each snapshot gave birth to: 2291 * (blocks born) = (my used) - (prev's used) + (blocks killed) 2292 * So a sequence would look like: 2293 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0) 2294 * Which simplifies to: 2295 * uN + kN + kN-1 + ... + k1 + k0 2296 * Note however, if we stop before we reach the ORIGIN we get: 2297 * uN + kN + kN-1 + ... + kM - uM-1 2298 */ 2299 pa->used = origin_ds->ds_phys->ds_used_bytes; 2300 pa->comp = origin_ds->ds_phys->ds_compressed_bytes; 2301 pa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 2302 for (snap = list_head(&pa->shared_snaps); snap; 2303 snap = list_next(&pa->shared_snaps, snap)) { 2304 uint64_t val, dlused, dlcomp, dluncomp; 2305 dsl_dataset_t *ds = snap->ds; 2306 2307 /* Check that the snapshot name does not conflict */ 2308 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2309 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2310 if (err == 0) 2311 return (EEXIST); 2312 if (err != ENOENT) 2313 return (err); 2314 2315 /* The very first snapshot does not have a deadlist */ 2316 if (ds->ds_phys->ds_prev_snap_obj == 0) 2317 continue; 2318 2319 if (err = bplist_space(&ds->ds_deadlist, 2320 &dlused, &dlcomp, &dluncomp)) 2321 return (err); 2322 pa->used += dlused; 2323 pa->comp += dlcomp; 2324 pa->uncomp += dluncomp; 2325 } 2326 2327 /* 2328 * If we are a clone of a clone then we never reached ORIGIN, 2329 * so we need to subtract out the clone origin's used space. 2330 */ 2331 if (pa->origin_origin) { 2332 pa->used -= pa->origin_origin->ds_phys->ds_used_bytes; 2333 pa->comp -= pa->origin_origin->ds_phys->ds_compressed_bytes; 2334 pa->uncomp -= pa->origin_origin->ds_phys->ds_uncompressed_bytes; 2335 } 2336 2337 /* Check that there is enough space here */ 2338 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir, 2339 pa->used); 2340 if (err) 2341 return (err); 2342 2343 /* 2344 * Compute the amounts of space that will be used by snapshots 2345 * after the promotion (for both origin and clone). For each, 2346 * it is the amount of space that will be on all of their 2347 * deadlists (that was not born before their new origin). 2348 */ 2349 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2350 uint64_t space; 2351 2352 /* 2353 * Note, typically this will not be a clone of a clone, 2354 * so snap->ds->ds_origin_txg will be < TXG_INITIAL, so 2355 * these snaplist_space() -> bplist_space_birthrange() 2356 * calls will be fast because they do not have to 2357 * iterate over all bps. 2358 */ 2359 snap = list_head(&pa->origin_snaps); 2360 err = snaplist_space(&pa->shared_snaps, 2361 snap->ds->ds_origin_txg, &pa->cloneusedsnap); 2362 if (err) 2363 return (err); 2364 2365 err = snaplist_space(&pa->clone_snaps, 2366 snap->ds->ds_origin_txg, &space); 2367 if (err) 2368 return (err); 2369 pa->cloneusedsnap += space; 2370 } 2371 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) { 2372 err = snaplist_space(&pa->origin_snaps, 2373 origin_ds->ds_phys->ds_creation_txg, &pa->originusedsnap); 2374 if (err) 2375 return (err); 2376 } 2377 2378 return (0); 2379 } 2380 2381 static void 2382 dsl_dataset_promote_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2383 { 2384 dsl_dataset_t *hds = arg1; 2385 struct promotearg *pa = arg2; 2386 struct promotenode *snap = list_head(&pa->shared_snaps); 2387 dsl_dataset_t *origin_ds = snap->ds; 2388 dsl_dataset_t *origin_head; 2389 dsl_dir_t *dd = hds->ds_dir; 2390 dsl_pool_t *dp = hds->ds_dir->dd_pool; 2391 dsl_dir_t *odd = NULL; 2392 uint64_t oldnext_obj; 2393 int64_t delta; 2394 2395 ASSERT(0 == (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE)); 2396 2397 snap = list_head(&pa->origin_snaps); 2398 origin_head = snap->ds; 2399 2400 /* 2401 * We need to explicitly open odd, since origin_ds's dd will be 2402 * changing. 2403 */ 2404 VERIFY(0 == dsl_dir_open_obj(dp, origin_ds->ds_dir->dd_object, 2405 NULL, FTAG, &odd)); 2406 2407 /* change origin's next snap */ 2408 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2409 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj; 2410 snap = list_tail(&pa->clone_snaps); 2411 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object); 2412 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object; 2413 2414 /* change the origin's next clone */ 2415 if (origin_ds->ds_phys->ds_next_clones_obj) { 2416 VERIFY3U(0, ==, zap_remove_int(dp->dp_meta_objset, 2417 origin_ds->ds_phys->ds_next_clones_obj, 2418 origin_ds->ds_phys->ds_next_snap_obj, tx)); 2419 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset, 2420 origin_ds->ds_phys->ds_next_clones_obj, 2421 oldnext_obj, tx)); 2422 } 2423 2424 /* change origin */ 2425 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2426 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2427 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2428 hds->ds_origin_txg = origin_head->ds_origin_txg; 2429 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2430 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2431 origin_head->ds_origin_txg = origin_ds->ds_phys->ds_creation_txg; 2432 2433 /* move snapshots to this dir */ 2434 for (snap = list_head(&pa->shared_snaps); snap; 2435 snap = list_next(&pa->shared_snaps, snap)) { 2436 dsl_dataset_t *ds = snap->ds; 2437 2438 /* unregister props as dsl_dir is changing */ 2439 if (ds->ds_user_ptr) { 2440 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 2441 ds->ds_user_ptr = NULL; 2442 } 2443 /* move snap name entry */ 2444 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2445 VERIFY(0 == dsl_dataset_snap_remove(origin_head, 2446 ds->ds_snapname, tx)); 2447 VERIFY(0 == zap_add(dp->dp_meta_objset, 2448 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2449 8, 1, &ds->ds_object, tx)); 2450 /* change containing dsl_dir */ 2451 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2452 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2453 ds->ds_phys->ds_dir_obj = dd->dd_object; 2454 ASSERT3P(ds->ds_dir, ==, odd); 2455 dsl_dir_close(ds->ds_dir, ds); 2456 VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object, 2457 NULL, ds, &ds->ds_dir)); 2458 2459 ASSERT3U(dsl_prop_numcb(ds), ==, 0); 2460 } 2461 2462 /* 2463 * Change space accounting. 2464 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either 2465 * both be valid, or both be 0 (resulting in delta == 0). This 2466 * is true for each of {clone,origin} independently. 2467 */ 2468 2469 delta = pa->cloneusedsnap - 2470 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2471 ASSERT3S(delta, >=, 0); 2472 ASSERT3U(pa->used, >=, delta); 2473 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx); 2474 dsl_dir_diduse_space(dd, DD_USED_HEAD, 2475 pa->used - delta, pa->comp, pa->uncomp, tx); 2476 2477 delta = pa->originusedsnap - 2478 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP]; 2479 ASSERT3S(delta, <=, 0); 2480 ASSERT3U(pa->used, >=, -delta); 2481 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx); 2482 dsl_dir_diduse_space(odd, DD_USED_HEAD, 2483 -pa->used - delta, -pa->comp, -pa->uncomp, tx); 2484 2485 origin_ds->ds_phys->ds_unique_bytes = pa->unique; 2486 2487 /* log history record */ 2488 spa_history_internal_log(LOG_DS_PROMOTE, dd->dd_pool->dp_spa, tx, 2489 cr, "dataset = %llu", hds->ds_object); 2490 2491 dsl_dir_close(odd, FTAG); 2492 } 2493 2494 static char *snaplist_tag = "snaplist"; 2495 /* 2496 * Make a list of dsl_dataset_t's for the snapshots between first_obj 2497 * (exclusive) and last_obj (inclusive). The list will be in reverse 2498 * order (last_obj will be the list_head()). If first_obj == 0, do all 2499 * snapshots back to this dataset's origin. 2500 */ 2501 static int 2502 snaplist_make(dsl_pool_t *dp, boolean_t own, 2503 uint64_t first_obj, uint64_t last_obj, list_t *l) 2504 { 2505 uint64_t obj = last_obj; 2506 2507 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock)); 2508 2509 list_create(l, sizeof (struct promotenode), 2510 offsetof(struct promotenode, link)); 2511 2512 while (obj != first_obj) { 2513 dsl_dataset_t *ds; 2514 struct promotenode *snap; 2515 int err; 2516 2517 if (own) { 2518 err = dsl_dataset_own_obj(dp, obj, 2519 0, snaplist_tag, &ds); 2520 if (err == 0) 2521 dsl_dataset_make_exclusive(ds, snaplist_tag); 2522 } else { 2523 err = dsl_dataset_hold_obj(dp, obj, snaplist_tag, &ds); 2524 } 2525 if (err == ENOENT) { 2526 /* lost race with snapshot destroy */ 2527 struct promotenode *last = list_tail(l); 2528 ASSERT(obj != last->ds->ds_phys->ds_prev_snap_obj); 2529 obj = last->ds->ds_phys->ds_prev_snap_obj; 2530 continue; 2531 } else if (err) { 2532 return (err); 2533 } 2534 2535 if (first_obj == 0) 2536 first_obj = ds->ds_dir->dd_phys->dd_origin_obj; 2537 2538 snap = kmem_alloc(sizeof (struct promotenode), KM_SLEEP); 2539 snap->ds = ds; 2540 list_insert_tail(l, snap); 2541 obj = ds->ds_phys->ds_prev_snap_obj; 2542 } 2543 2544 return (0); 2545 } 2546 2547 static int 2548 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep) 2549 { 2550 struct promotenode *snap; 2551 2552 *spacep = 0; 2553 for (snap = list_head(l); snap; snap = list_next(l, snap)) { 2554 uint64_t used; 2555 int err = bplist_space_birthrange(&snap->ds->ds_deadlist, 2556 mintxg, UINT64_MAX, &used); 2557 if (err) 2558 return (err); 2559 *spacep += used; 2560 } 2561 return (0); 2562 } 2563 2564 static void 2565 snaplist_destroy(list_t *l, boolean_t own) 2566 { 2567 struct promotenode *snap; 2568 2569 if (!list_link_active(&l->list_head)) 2570 return; 2571 2572 while ((snap = list_tail(l)) != NULL) { 2573 list_remove(l, snap); 2574 if (own) 2575 dsl_dataset_disown(snap->ds, snaplist_tag); 2576 else 2577 dsl_dataset_rele(snap->ds, snaplist_tag); 2578 kmem_free(snap, sizeof (struct promotenode)); 2579 } 2580 list_destroy(l); 2581 } 2582 2583 /* 2584 * Promote a clone. Nomenclature note: 2585 * "clone" or "cds": the original clone which is being promoted 2586 * "origin" or "ods": the snapshot which is originally clone's origin 2587 * "origin head" or "ohds": the dataset which is the head 2588 * (filesystem/volume) for the origin 2589 * "origin origin": the origin of the origin's filesystem (typically 2590 * NULL, indicating that the clone is not a clone of a clone). 2591 */ 2592 int 2593 dsl_dataset_promote(const char *name) 2594 { 2595 dsl_dataset_t *ds; 2596 dsl_dir_t *dd; 2597 dsl_pool_t *dp; 2598 dmu_object_info_t doi; 2599 struct promotearg pa = { 0 }; 2600 struct promotenode *snap; 2601 int err; 2602 2603 err = dsl_dataset_hold(name, FTAG, &ds); 2604 if (err) 2605 return (err); 2606 dd = ds->ds_dir; 2607 dp = dd->dd_pool; 2608 2609 err = dmu_object_info(dp->dp_meta_objset, 2610 ds->ds_phys->ds_snapnames_zapobj, &doi); 2611 if (err) { 2612 dsl_dataset_rele(ds, FTAG); 2613 return (err); 2614 } 2615 2616 if (dsl_dataset_is_snapshot(ds) || dd->dd_phys->dd_origin_obj == 0) { 2617 dsl_dataset_rele(ds, FTAG); 2618 return (EINVAL); 2619 } 2620 2621 /* 2622 * We are going to inherit all the snapshots taken before our 2623 * origin (i.e., our new origin will be our parent's origin). 2624 * Take ownership of them so that we can rename them into our 2625 * namespace. 2626 */ 2627 rw_enter(&dp->dp_config_rwlock, RW_READER); 2628 2629 err = snaplist_make(dp, B_TRUE, 0, dd->dd_phys->dd_origin_obj, 2630 &pa.shared_snaps); 2631 if (err != 0) 2632 goto out; 2633 2634 err = snaplist_make(dp, B_FALSE, 0, ds->ds_object, &pa.clone_snaps); 2635 if (err != 0) 2636 goto out; 2637 2638 snap = list_head(&pa.shared_snaps); 2639 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj); 2640 err = snaplist_make(dp, B_FALSE, dd->dd_phys->dd_origin_obj, 2641 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, &pa.origin_snaps); 2642 if (err != 0) 2643 goto out; 2644 2645 if (dsl_dir_is_clone(snap->ds->ds_dir)) { 2646 err = dsl_dataset_own_obj(dp, 2647 snap->ds->ds_dir->dd_phys->dd_origin_obj, 2648 0, FTAG, &pa.origin_origin); 2649 if (err != 0) 2650 goto out; 2651 } 2652 2653 out: 2654 rw_exit(&dp->dp_config_rwlock); 2655 2656 /* 2657 * Add in 128x the snapnames zapobj size, since we will be moving 2658 * a bunch of snapnames to the promoted ds, and dirtying their 2659 * bonus buffers. 2660 */ 2661 if (err == 0) { 2662 err = dsl_sync_task_do(dp, dsl_dataset_promote_check, 2663 dsl_dataset_promote_sync, ds, &pa, 2664 2 + 2 * doi.doi_physical_blks); 2665 } 2666 2667 snaplist_destroy(&pa.shared_snaps, B_TRUE); 2668 snaplist_destroy(&pa.clone_snaps, B_FALSE); 2669 snaplist_destroy(&pa.origin_snaps, B_FALSE); 2670 if (pa.origin_origin) 2671 dsl_dataset_disown(pa.origin_origin, FTAG); 2672 dsl_dataset_rele(ds, FTAG); 2673 return (err); 2674 } 2675 2676 struct cloneswaparg { 2677 dsl_dataset_t *cds; /* clone dataset */ 2678 dsl_dataset_t *ohds; /* origin's head dataset */ 2679 boolean_t force; 2680 int64_t unused_refres_delta; /* change in unconsumed refreservation */ 2681 }; 2682 2683 /* ARGSUSED */ 2684 static int 2685 dsl_dataset_clone_swap_check(void *arg1, void *arg2, dmu_tx_t *tx) 2686 { 2687 struct cloneswaparg *csa = arg1; 2688 2689 /* they should both be heads */ 2690 if (dsl_dataset_is_snapshot(csa->cds) || 2691 dsl_dataset_is_snapshot(csa->ohds)) 2692 return (EINVAL); 2693 2694 /* the branch point should be just before them */ 2695 if (csa->cds->ds_prev != csa->ohds->ds_prev) 2696 return (EINVAL); 2697 2698 /* cds should be the clone */ 2699 if (csa->cds->ds_prev->ds_phys->ds_next_snap_obj != 2700 csa->ohds->ds_object) 2701 return (EINVAL); 2702 2703 /* the clone should be a child of the origin */ 2704 if (csa->cds->ds_dir->dd_parent != csa->ohds->ds_dir) 2705 return (EINVAL); 2706 2707 /* ohds shouldn't be modified unless 'force' */ 2708 if (!csa->force && dsl_dataset_modified_since_lastsnap(csa->ohds)) 2709 return (ETXTBSY); 2710 2711 /* adjust amount of any unconsumed refreservation */ 2712 csa->unused_refres_delta = 2713 (int64_t)MIN(csa->ohds->ds_reserved, 2714 csa->ohds->ds_phys->ds_unique_bytes) - 2715 (int64_t)MIN(csa->ohds->ds_reserved, 2716 csa->cds->ds_phys->ds_unique_bytes); 2717 2718 if (csa->unused_refres_delta > 0 && 2719 csa->unused_refres_delta > 2720 dsl_dir_space_available(csa->ohds->ds_dir, NULL, 0, TRUE)) 2721 return (ENOSPC); 2722 2723 return (0); 2724 } 2725 2726 /* ARGSUSED */ 2727 static void 2728 dsl_dataset_clone_swap_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2729 { 2730 struct cloneswaparg *csa = arg1; 2731 dsl_pool_t *dp = csa->cds->ds_dir->dd_pool; 2732 2733 ASSERT(csa->cds->ds_reserved == 0); 2734 ASSERT(csa->cds->ds_quota == csa->ohds->ds_quota); 2735 2736 dmu_buf_will_dirty(csa->cds->ds_dbuf, tx); 2737 dmu_buf_will_dirty(csa->ohds->ds_dbuf, tx); 2738 dmu_buf_will_dirty(csa->cds->ds_prev->ds_dbuf, tx); 2739 2740 if (csa->cds->ds_user_ptr != NULL) { 2741 csa->cds->ds_user_evict_func(csa->cds, csa->cds->ds_user_ptr); 2742 csa->cds->ds_user_ptr = NULL; 2743 } 2744 2745 if (csa->ohds->ds_user_ptr != NULL) { 2746 csa->ohds->ds_user_evict_func(csa->ohds, 2747 csa->ohds->ds_user_ptr); 2748 csa->ohds->ds_user_ptr = NULL; 2749 } 2750 2751 /* reset origin's unique bytes */ 2752 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2753 csa->cds->ds_prev->ds_phys->ds_prev_snap_txg, UINT64_MAX, 2754 &csa->cds->ds_prev->ds_phys->ds_unique_bytes)); 2755 2756 /* swap blkptrs */ 2757 { 2758 blkptr_t tmp; 2759 tmp = csa->ohds->ds_phys->ds_bp; 2760 csa->ohds->ds_phys->ds_bp = csa->cds->ds_phys->ds_bp; 2761 csa->cds->ds_phys->ds_bp = tmp; 2762 } 2763 2764 /* set dd_*_bytes */ 2765 { 2766 int64_t dused, dcomp, duncomp; 2767 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2768 uint64_t odl_used, odl_comp, odl_uncomp; 2769 2770 ASSERT3U(csa->cds->ds_dir->dd_phys-> 2771 dd_used_breakdown[DD_USED_SNAP], ==, 0); 2772 2773 VERIFY(0 == bplist_space(&csa->cds->ds_deadlist, &cdl_used, 2774 &cdl_comp, &cdl_uncomp)); 2775 VERIFY(0 == bplist_space(&csa->ohds->ds_deadlist, &odl_used, 2776 &odl_comp, &odl_uncomp)); 2777 2778 dused = csa->cds->ds_phys->ds_used_bytes + cdl_used - 2779 (csa->ohds->ds_phys->ds_used_bytes + odl_used); 2780 dcomp = csa->cds->ds_phys->ds_compressed_bytes + cdl_comp - 2781 (csa->ohds->ds_phys->ds_compressed_bytes + odl_comp); 2782 duncomp = csa->cds->ds_phys->ds_uncompressed_bytes + 2783 cdl_uncomp - 2784 (csa->ohds->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2785 2786 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_HEAD, 2787 dused, dcomp, duncomp, tx); 2788 dsl_dir_diduse_space(csa->cds->ds_dir, DD_USED_HEAD, 2789 -dused, -dcomp, -duncomp, tx); 2790 2791 /* 2792 * The difference in the space used by snapshots is the 2793 * difference in snapshot space due to the head's 2794 * deadlist (since that's the only thing that's 2795 * changing that affects the snapused). 2796 */ 2797 VERIFY(0 == bplist_space_birthrange(&csa->cds->ds_deadlist, 2798 csa->ohds->ds_origin_txg, UINT64_MAX, &cdl_used)); 2799 VERIFY(0 == bplist_space_birthrange(&csa->ohds->ds_deadlist, 2800 csa->ohds->ds_origin_txg, UINT64_MAX, &odl_used)); 2801 dsl_dir_transfer_space(csa->ohds->ds_dir, cdl_used - odl_used, 2802 DD_USED_HEAD, DD_USED_SNAP, tx); 2803 } 2804 2805 #define SWITCH64(x, y) \ 2806 { \ 2807 uint64_t __tmp = (x); \ 2808 (x) = (y); \ 2809 (y) = __tmp; \ 2810 } 2811 2812 /* swap ds_*_bytes */ 2813 SWITCH64(csa->ohds->ds_phys->ds_used_bytes, 2814 csa->cds->ds_phys->ds_used_bytes); 2815 SWITCH64(csa->ohds->ds_phys->ds_compressed_bytes, 2816 csa->cds->ds_phys->ds_compressed_bytes); 2817 SWITCH64(csa->ohds->ds_phys->ds_uncompressed_bytes, 2818 csa->cds->ds_phys->ds_uncompressed_bytes); 2819 SWITCH64(csa->ohds->ds_phys->ds_unique_bytes, 2820 csa->cds->ds_phys->ds_unique_bytes); 2821 2822 /* apply any parent delta for change in unconsumed refreservation */ 2823 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_REFRSRV, 2824 csa->unused_refres_delta, 0, 0, tx); 2825 2826 /* swap deadlists */ 2827 bplist_close(&csa->cds->ds_deadlist); 2828 bplist_close(&csa->ohds->ds_deadlist); 2829 SWITCH64(csa->ohds->ds_phys->ds_deadlist_obj, 2830 csa->cds->ds_phys->ds_deadlist_obj); 2831 VERIFY(0 == bplist_open(&csa->cds->ds_deadlist, dp->dp_meta_objset, 2832 csa->cds->ds_phys->ds_deadlist_obj)); 2833 VERIFY(0 == bplist_open(&csa->ohds->ds_deadlist, dp->dp_meta_objset, 2834 csa->ohds->ds_phys->ds_deadlist_obj)); 2835 } 2836 2837 /* 2838 * Swap 'clone' with its origin head file system. Used at the end 2839 * of "online recv" to swizzle the file system to the new version. 2840 */ 2841 int 2842 dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head, 2843 boolean_t force) 2844 { 2845 struct cloneswaparg csa; 2846 int error; 2847 2848 ASSERT(clone->ds_owner); 2849 ASSERT(origin_head->ds_owner); 2850 retry: 2851 /* Need exclusive access for the swap */ 2852 rw_enter(&clone->ds_rwlock, RW_WRITER); 2853 if (!rw_tryenter(&origin_head->ds_rwlock, RW_WRITER)) { 2854 rw_exit(&clone->ds_rwlock); 2855 rw_enter(&origin_head->ds_rwlock, RW_WRITER); 2856 if (!rw_tryenter(&clone->ds_rwlock, RW_WRITER)) { 2857 rw_exit(&origin_head->ds_rwlock); 2858 goto retry; 2859 } 2860 } 2861 csa.cds = clone; 2862 csa.ohds = origin_head; 2863 csa.force = force; 2864 error = dsl_sync_task_do(clone->ds_dir->dd_pool, 2865 dsl_dataset_clone_swap_check, 2866 dsl_dataset_clone_swap_sync, &csa, NULL, 9); 2867 return (error); 2868 } 2869 2870 /* 2871 * Given a pool name and a dataset object number in that pool, 2872 * return the name of that dataset. 2873 */ 2874 int 2875 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2876 { 2877 spa_t *spa; 2878 dsl_pool_t *dp; 2879 dsl_dataset_t *ds; 2880 int error; 2881 2882 if ((error = spa_open(pname, &spa, FTAG)) != 0) 2883 return (error); 2884 dp = spa_get_dsl(spa); 2885 rw_enter(&dp->dp_config_rwlock, RW_READER); 2886 if ((error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds)) == 0) { 2887 dsl_dataset_name(ds, buf); 2888 dsl_dataset_rele(ds, FTAG); 2889 } 2890 rw_exit(&dp->dp_config_rwlock); 2891 spa_close(spa, FTAG); 2892 2893 return (error); 2894 } 2895 2896 int 2897 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2898 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2899 { 2900 int error = 0; 2901 2902 ASSERT3S(asize, >, 0); 2903 2904 /* 2905 * *ref_rsrv is the portion of asize that will come from any 2906 * unconsumed refreservation space. 2907 */ 2908 *ref_rsrv = 0; 2909 2910 mutex_enter(&ds->ds_lock); 2911 /* 2912 * Make a space adjustment for reserved bytes. 2913 */ 2914 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2915 ASSERT3U(*used, >=, 2916 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2917 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2918 *ref_rsrv = 2919 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2920 } 2921 2922 if (!check_quota || ds->ds_quota == 0) { 2923 mutex_exit(&ds->ds_lock); 2924 return (0); 2925 } 2926 /* 2927 * If they are requesting more space, and our current estimate 2928 * is over quota, they get to try again unless the actual 2929 * on-disk is over quota and there are no pending changes (which 2930 * may free up space for us). 2931 */ 2932 if (ds->ds_phys->ds_used_bytes + inflight >= ds->ds_quota) { 2933 if (inflight > 0 || ds->ds_phys->ds_used_bytes < ds->ds_quota) 2934 error = ERESTART; 2935 else 2936 error = EDQUOT; 2937 } 2938 mutex_exit(&ds->ds_lock); 2939 2940 return (error); 2941 } 2942 2943 /* ARGSUSED */ 2944 static int 2945 dsl_dataset_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx) 2946 { 2947 dsl_dataset_t *ds = arg1; 2948 uint64_t *quotap = arg2; 2949 uint64_t new_quota = *quotap; 2950 2951 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_REFQUOTA) 2952 return (ENOTSUP); 2953 2954 if (new_quota == 0) 2955 return (0); 2956 2957 if (new_quota < ds->ds_phys->ds_used_bytes || 2958 new_quota < ds->ds_reserved) 2959 return (ENOSPC); 2960 2961 return (0); 2962 } 2963 2964 /* ARGSUSED */ 2965 void 2966 dsl_dataset_set_quota_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2967 { 2968 dsl_dataset_t *ds = arg1; 2969 uint64_t *quotap = arg2; 2970 uint64_t new_quota = *quotap; 2971 2972 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2973 2974 ds->ds_quota = new_quota; 2975 2976 dsl_prop_set_uint64_sync(ds->ds_dir, "refquota", new_quota, cr, tx); 2977 2978 spa_history_internal_log(LOG_DS_REFQUOTA, ds->ds_dir->dd_pool->dp_spa, 2979 tx, cr, "%lld dataset = %llu ", 2980 (longlong_t)new_quota, ds->ds_object); 2981 } 2982 2983 int 2984 dsl_dataset_set_quota(const char *dsname, uint64_t quota) 2985 { 2986 dsl_dataset_t *ds; 2987 int err; 2988 2989 err = dsl_dataset_hold(dsname, FTAG, &ds); 2990 if (err) 2991 return (err); 2992 2993 if (quota != ds->ds_quota) { 2994 /* 2995 * If someone removes a file, then tries to set the quota, we 2996 * want to make sure the file freeing takes effect. 2997 */ 2998 txg_wait_open(ds->ds_dir->dd_pool, 0); 2999 3000 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3001 dsl_dataset_set_quota_check, dsl_dataset_set_quota_sync, 3002 ds, "a, 0); 3003 } 3004 dsl_dataset_rele(ds, FTAG); 3005 return (err); 3006 } 3007 3008 static int 3009 dsl_dataset_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx) 3010 { 3011 dsl_dataset_t *ds = arg1; 3012 uint64_t *reservationp = arg2; 3013 uint64_t new_reservation = *reservationp; 3014 int64_t delta; 3015 uint64_t unique; 3016 3017 if (new_reservation > INT64_MAX) 3018 return (EOVERFLOW); 3019 3020 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < 3021 SPA_VERSION_REFRESERVATION) 3022 return (ENOTSUP); 3023 3024 if (dsl_dataset_is_snapshot(ds)) 3025 return (EINVAL); 3026 3027 /* 3028 * If we are doing the preliminary check in open context, the 3029 * space estimates may be inaccurate. 3030 */ 3031 if (!dmu_tx_is_syncing(tx)) 3032 return (0); 3033 3034 mutex_enter(&ds->ds_lock); 3035 unique = dsl_dataset_unique(ds); 3036 delta = MAX(unique, new_reservation) - MAX(unique, ds->ds_reserved); 3037 mutex_exit(&ds->ds_lock); 3038 3039 if (delta > 0 && 3040 delta > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 3041 return (ENOSPC); 3042 if (delta > 0 && ds->ds_quota > 0 && 3043 new_reservation > ds->ds_quota) 3044 return (ENOSPC); 3045 3046 return (0); 3047 } 3048 3049 /* ARGSUSED */ 3050 static void 3051 dsl_dataset_set_reservation_sync(void *arg1, void *arg2, cred_t *cr, 3052 dmu_tx_t *tx) 3053 { 3054 dsl_dataset_t *ds = arg1; 3055 uint64_t *reservationp = arg2; 3056 uint64_t new_reservation = *reservationp; 3057 uint64_t unique; 3058 int64_t delta; 3059 3060 dmu_buf_will_dirty(ds->ds_dbuf, tx); 3061 3062 mutex_enter(&ds->ds_lock); 3063 unique = dsl_dataset_unique(ds); 3064 delta = MAX(0, (int64_t)(new_reservation - unique)) - 3065 MAX(0, (int64_t)(ds->ds_reserved - unique)); 3066 ds->ds_reserved = new_reservation; 3067 mutex_exit(&ds->ds_lock); 3068 3069 dsl_prop_set_uint64_sync(ds->ds_dir, "refreservation", 3070 new_reservation, cr, tx); 3071 3072 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx); 3073 3074 spa_history_internal_log(LOG_DS_REFRESERV, 3075 ds->ds_dir->dd_pool->dp_spa, tx, cr, "%lld dataset = %llu", 3076 (longlong_t)new_reservation, 3077 ds->ds_dir->dd_phys->dd_head_dataset_obj); 3078 } 3079 3080 int 3081 dsl_dataset_set_reservation(const char *dsname, uint64_t reservation) 3082 { 3083 dsl_dataset_t *ds; 3084 int err; 3085 3086 err = dsl_dataset_hold(dsname, FTAG, &ds); 3087 if (err) 3088 return (err); 3089 3090 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 3091 dsl_dataset_set_reservation_check, 3092 dsl_dataset_set_reservation_sync, ds, &reservation, 0); 3093 dsl_dataset_rele(ds, FTAG); 3094 return (err); 3095 } 3096