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 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/dmu_objset.h> 29 #include <sys/dsl_dataset.h> 30 #include <sys/dsl_dir.h> 31 #include <sys/dsl_prop.h> 32 #include <sys/dsl_synctask.h> 33 #include <sys/dmu_traverse.h> 34 #include <sys/dmu_tx.h> 35 #include <sys/arc.h> 36 #include <sys/zio.h> 37 #include <sys/zap.h> 38 #include <sys/unique.h> 39 #include <sys/zfs_context.h> 40 #include <sys/zfs_ioctl.h> 41 #include <sys/spa.h> 42 #include <sys/sunddi.h> 43 44 static char *dsl_reaper = "the grim reaper"; 45 46 static dsl_checkfunc_t dsl_dataset_destroy_begin_check; 47 static dsl_syncfunc_t dsl_dataset_destroy_begin_sync; 48 static dsl_checkfunc_t dsl_dataset_rollback_check; 49 static dsl_syncfunc_t dsl_dataset_rollback_sync; 50 static dsl_syncfunc_t dsl_dataset_set_reservation_sync; 51 52 #define DS_REF_MAX (1ULL << 62) 53 54 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE 55 56 #define DSL_DATASET_IS_DESTROYED(ds) ((ds)->ds_owner == dsl_reaper) 57 58 static void dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag); 59 60 /* 61 * Figure out how much of this delta should be propogated to the dsl_dir 62 * layer. If there's a refreservation, that space has already been 63 * partially accounted for in our ancestors. 64 */ 65 static int64_t 66 parent_delta(dsl_dataset_t *ds, int64_t delta) 67 { 68 uint64_t old_bytes, new_bytes; 69 70 if (ds->ds_reserved == 0) 71 return (delta); 72 73 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved); 74 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved); 75 76 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta)); 77 return (new_bytes - old_bytes); 78 } 79 80 void 81 dsl_dataset_block_born(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 82 { 83 int used = bp_get_dasize(tx->tx_pool->dp_spa, bp); 84 int compressed = BP_GET_PSIZE(bp); 85 int uncompressed = BP_GET_UCSIZE(bp); 86 int64_t delta; 87 88 dprintf_bp(bp, "born, ds=%p\n", ds); 89 90 ASSERT(dmu_tx_is_syncing(tx)); 91 /* It could have been compressed away to nothing */ 92 if (BP_IS_HOLE(bp)) 93 return; 94 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE); 95 ASSERT3U(BP_GET_TYPE(bp), <, DMU_OT_NUMTYPES); 96 if (ds == NULL) { 97 /* 98 * Account for the meta-objset space in its placeholder 99 * dsl_dir. 100 */ 101 ASSERT3U(compressed, ==, uncompressed); /* it's all metadata */ 102 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, 103 used, compressed, uncompressed, tx); 104 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx); 105 return; 106 } 107 dmu_buf_will_dirty(ds->ds_dbuf, tx); 108 mutex_enter(&ds->ds_lock); 109 delta = parent_delta(ds, used); 110 ds->ds_phys->ds_used_bytes += used; 111 ds->ds_phys->ds_compressed_bytes += compressed; 112 ds->ds_phys->ds_uncompressed_bytes += uncompressed; 113 ds->ds_phys->ds_unique_bytes += used; 114 mutex_exit(&ds->ds_lock); 115 dsl_dir_diduse_space(ds->ds_dir, delta, compressed, uncompressed, tx); 116 } 117 118 void 119 dsl_dataset_block_kill(dsl_dataset_t *ds, blkptr_t *bp, zio_t *pio, 120 dmu_tx_t *tx) 121 { 122 int used = bp_get_dasize(tx->tx_pool->dp_spa, bp); 123 int compressed = BP_GET_PSIZE(bp); 124 int uncompressed = BP_GET_UCSIZE(bp); 125 126 ASSERT(dmu_tx_is_syncing(tx)); 127 /* No block pointer => nothing to free */ 128 if (BP_IS_HOLE(bp)) 129 return; 130 131 ASSERT(used > 0); 132 if (ds == NULL) { 133 int err; 134 /* 135 * Account for the meta-objset space in its placeholder 136 * dataset. 137 */ 138 err = arc_free(pio, tx->tx_pool->dp_spa, 139 tx->tx_txg, bp, NULL, NULL, pio ? ARC_NOWAIT: ARC_WAIT); 140 ASSERT(err == 0); 141 142 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, 143 -used, -compressed, -uncompressed, tx); 144 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx); 145 return; 146 } 147 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool); 148 149 dmu_buf_will_dirty(ds->ds_dbuf, tx); 150 151 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) { 152 int err; 153 int64_t delta; 154 155 dprintf_bp(bp, "freeing: %s", ""); 156 err = arc_free(pio, tx->tx_pool->dp_spa, 157 tx->tx_txg, bp, NULL, NULL, pio ? ARC_NOWAIT: ARC_WAIT); 158 ASSERT(err == 0); 159 160 mutex_enter(&ds->ds_lock); 161 ASSERT(ds->ds_phys->ds_unique_bytes >= used || 162 !DS_UNIQUE_IS_ACCURATE(ds)); 163 delta = parent_delta(ds, -used); 164 ds->ds_phys->ds_unique_bytes -= used; 165 mutex_exit(&ds->ds_lock); 166 dsl_dir_diduse_space(ds->ds_dir, 167 delta, -compressed, -uncompressed, tx); 168 } else { 169 dprintf_bp(bp, "putting on dead list: %s", ""); 170 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, bp, tx)); 171 ASSERT3U(ds->ds_prev->ds_object, ==, 172 ds->ds_phys->ds_prev_snap_obj); 173 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0); 174 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */ 175 if (ds->ds_prev->ds_phys->ds_next_snap_obj == 176 ds->ds_object && bp->blk_birth > 177 ds->ds_prev->ds_phys->ds_prev_snap_txg) { 178 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 179 mutex_enter(&ds->ds_prev->ds_lock); 180 ds->ds_prev->ds_phys->ds_unique_bytes += used; 181 mutex_exit(&ds->ds_prev->ds_lock); 182 } 183 } 184 mutex_enter(&ds->ds_lock); 185 ASSERT3U(ds->ds_phys->ds_used_bytes, >=, used); 186 ds->ds_phys->ds_used_bytes -= used; 187 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed); 188 ds->ds_phys->ds_compressed_bytes -= compressed; 189 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed); 190 ds->ds_phys->ds_uncompressed_bytes -= uncompressed; 191 mutex_exit(&ds->ds_lock); 192 } 193 194 uint64_t 195 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds) 196 { 197 uint64_t trysnap = 0; 198 199 if (ds == NULL) 200 return (0); 201 /* 202 * The snapshot creation could fail, but that would cause an 203 * incorrect FALSE return, which would only result in an 204 * overestimation of the amount of space that an operation would 205 * consume, which is OK. 206 * 207 * There's also a small window where we could miss a pending 208 * snapshot, because we could set the sync task in the quiescing 209 * phase. So this should only be used as a guess. 210 */ 211 if (ds->ds_trysnap_txg > 212 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa)) 213 trysnap = ds->ds_trysnap_txg; 214 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap)); 215 } 216 217 int 218 dsl_dataset_block_freeable(dsl_dataset_t *ds, uint64_t blk_birth) 219 { 220 return (blk_birth > dsl_dataset_prev_snap_txg(ds)); 221 } 222 223 /* ARGSUSED */ 224 static void 225 dsl_dataset_evict(dmu_buf_t *db, void *dsv) 226 { 227 dsl_dataset_t *ds = dsv; 228 229 ASSERT(ds->ds_owner == NULL || DSL_DATASET_IS_DESTROYED(ds)); 230 231 dprintf_ds(ds, "evicting %s\n", ""); 232 233 unique_remove(ds->ds_fsid_guid); 234 235 if (ds->ds_user_ptr != NULL) 236 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 237 238 if (ds->ds_prev) { 239 dsl_dataset_drop_ref(ds->ds_prev, ds); 240 ds->ds_prev = NULL; 241 } 242 243 bplist_close(&ds->ds_deadlist); 244 if (ds->ds_dir) 245 dsl_dir_close(ds->ds_dir, ds); 246 247 ASSERT(!list_link_active(&ds->ds_synced_link)); 248 249 mutex_destroy(&ds->ds_lock); 250 mutex_destroy(&ds->ds_opening_lock); 251 mutex_destroy(&ds->ds_deadlist.bpl_lock); 252 rw_destroy(&ds->ds_rwlock); 253 cv_destroy(&ds->ds_exclusive_cv); 254 255 kmem_free(ds, sizeof (dsl_dataset_t)); 256 } 257 258 static int 259 dsl_dataset_get_snapname(dsl_dataset_t *ds) 260 { 261 dsl_dataset_phys_t *headphys; 262 int err; 263 dmu_buf_t *headdbuf; 264 dsl_pool_t *dp = ds->ds_dir->dd_pool; 265 objset_t *mos = dp->dp_meta_objset; 266 267 if (ds->ds_snapname[0]) 268 return (0); 269 if (ds->ds_phys->ds_next_snap_obj == 0) 270 return (0); 271 272 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj, 273 FTAG, &headdbuf); 274 if (err) 275 return (err); 276 headphys = headdbuf->db_data; 277 err = zap_value_search(dp->dp_meta_objset, 278 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname); 279 dmu_buf_rele(headdbuf, FTAG); 280 return (err); 281 } 282 283 static int 284 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value) 285 { 286 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 287 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 288 matchtype_t mt; 289 int err; 290 291 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 292 mt = MT_FIRST; 293 else 294 mt = MT_EXACT; 295 296 err = zap_lookup_norm(mos, snapobj, name, 8, 1, 297 value, mt, NULL, 0, NULL); 298 if (err == ENOTSUP && mt == MT_FIRST) 299 err = zap_lookup(mos, snapobj, name, 8, 1, value); 300 return (err); 301 } 302 303 static int 304 dsl_dataset_snap_remove(dsl_dataset_t *ds, char *name, dmu_tx_t *tx) 305 { 306 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 307 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj; 308 matchtype_t mt; 309 int err; 310 311 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET) 312 mt = MT_FIRST; 313 else 314 mt = MT_EXACT; 315 316 err = zap_remove_norm(mos, snapobj, name, mt, tx); 317 if (err == ENOTSUP && mt == MT_FIRST) 318 err = zap_remove(mos, snapobj, name, tx); 319 return (err); 320 } 321 322 static int 323 dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag, 324 dsl_dataset_t **dsp) 325 { 326 objset_t *mos = dp->dp_meta_objset; 327 dmu_buf_t *dbuf; 328 dsl_dataset_t *ds; 329 int err; 330 331 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 332 dsl_pool_sync_context(dp)); 333 334 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf); 335 if (err) 336 return (err); 337 ds = dmu_buf_get_user(dbuf); 338 if (ds == NULL) { 339 dsl_dataset_t *winner; 340 341 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP); 342 ds->ds_dbuf = dbuf; 343 ds->ds_object = dsobj; 344 ds->ds_phys = dbuf->db_data; 345 346 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL); 347 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL); 348 mutex_init(&ds->ds_deadlist.bpl_lock, NULL, MUTEX_DEFAULT, 349 NULL); 350 rw_init(&ds->ds_rwlock, 0, 0, 0); 351 cv_init(&ds->ds_exclusive_cv, NULL, CV_DEFAULT, NULL); 352 353 err = bplist_open(&ds->ds_deadlist, 354 mos, ds->ds_phys->ds_deadlist_obj); 355 if (err == 0) { 356 err = dsl_dir_open_obj(dp, 357 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir); 358 } 359 if (err) { 360 /* 361 * we don't really need to close the blist if we 362 * just opened it. 363 */ 364 mutex_destroy(&ds->ds_lock); 365 mutex_destroy(&ds->ds_opening_lock); 366 mutex_destroy(&ds->ds_deadlist.bpl_lock); 367 rw_destroy(&ds->ds_rwlock); 368 cv_destroy(&ds->ds_exclusive_cv); 369 kmem_free(ds, sizeof (dsl_dataset_t)); 370 dmu_buf_rele(dbuf, tag); 371 return (err); 372 } 373 374 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == dsobj) { 375 ds->ds_snapname[0] = '\0'; 376 if (ds->ds_phys->ds_prev_snap_obj) { 377 err = dsl_dataset_get_ref(dp, 378 ds->ds_phys->ds_prev_snap_obj, 379 ds, &ds->ds_prev); 380 } 381 } else if (zfs_flags & ZFS_DEBUG_SNAPNAMES) { 382 err = dsl_dataset_get_snapname(ds); 383 } 384 385 if (!dsl_dataset_is_snapshot(ds)) { 386 /* 387 * In sync context, we're called with either no lock 388 * or with the write lock. If we're not syncing, 389 * we're always called with the read lock held. 390 */ 391 boolean_t need_lock = 392 !RW_WRITE_HELD(&dp->dp_config_rwlock) && 393 dsl_pool_sync_context(dp); 394 395 if (need_lock) 396 rw_enter(&dp->dp_config_rwlock, RW_READER); 397 398 err = dsl_prop_get_ds_locked(ds->ds_dir, 399 "refreservation", sizeof (uint64_t), 1, 400 &ds->ds_reserved, NULL); 401 if (err == 0) { 402 err = dsl_prop_get_ds_locked(ds->ds_dir, 403 "refquota", sizeof (uint64_t), 1, 404 &ds->ds_quota, NULL); 405 } 406 407 if (need_lock) 408 rw_exit(&dp->dp_config_rwlock); 409 } else { 410 ds->ds_reserved = ds->ds_quota = 0; 411 } 412 413 if (err == 0) { 414 winner = dmu_buf_set_user_ie(dbuf, ds, &ds->ds_phys, 415 dsl_dataset_evict); 416 } 417 if (err || winner) { 418 bplist_close(&ds->ds_deadlist); 419 if (ds->ds_prev) 420 dsl_dataset_drop_ref(ds->ds_prev, ds); 421 dsl_dir_close(ds->ds_dir, ds); 422 mutex_destroy(&ds->ds_lock); 423 mutex_destroy(&ds->ds_opening_lock); 424 mutex_destroy(&ds->ds_deadlist.bpl_lock); 425 rw_destroy(&ds->ds_rwlock); 426 cv_destroy(&ds->ds_exclusive_cv); 427 kmem_free(ds, sizeof (dsl_dataset_t)); 428 if (err) { 429 dmu_buf_rele(dbuf, tag); 430 return (err); 431 } 432 ds = winner; 433 } else { 434 ds->ds_fsid_guid = 435 unique_insert(ds->ds_phys->ds_fsid_guid); 436 } 437 } 438 ASSERT3P(ds->ds_dbuf, ==, dbuf); 439 ASSERT3P(ds->ds_phys, ==, dbuf->db_data); 440 mutex_enter(&ds->ds_lock); 441 if (!dsl_pool_sync_context(dp) && DSL_DATASET_IS_DESTROYED(ds)) { 442 mutex_exit(&ds->ds_lock); 443 dmu_buf_rele(ds->ds_dbuf, tag); 444 return (ENOENT); 445 } 446 mutex_exit(&ds->ds_lock); 447 *dsp = ds; 448 return (0); 449 } 450 451 static int 452 dsl_dataset_hold_ref(dsl_dataset_t *ds, void *tag) 453 { 454 dsl_pool_t *dp = ds->ds_dir->dd_pool; 455 456 /* 457 * In syncing context we don't want the rwlock lock: there 458 * may be an existing writer waiting for sync phase to 459 * finish. We don't need to worry about such writers, since 460 * sync phase is single-threaded, so the writer can't be 461 * doing anything while we are active. 462 */ 463 if (dsl_pool_sync_context(dp)) { 464 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 465 return (0); 466 } 467 468 /* 469 * Normal users will hold the ds_rwlock as a READER until they 470 * are finished (i.e., call dsl_dataset_rele()). "Owners" will 471 * drop their READER lock after they set the ds_owner field. 472 * 473 * If the dataset is being destroyed, the destroy thread will 474 * obtain a WRITER lock for exclusive access after it's done its 475 * open-context work and then change the ds_owner to 476 * dsl_reaper once destruction is assured. So threads 477 * may block here temporarily, until the "destructability" of 478 * the dataset is determined. 479 */ 480 ASSERT(!RW_WRITE_HELD(&dp->dp_config_rwlock)); 481 mutex_enter(&ds->ds_lock); 482 while (!rw_tryenter(&ds->ds_rwlock, RW_READER)) { 483 rw_exit(&dp->dp_config_rwlock); 484 cv_wait(&ds->ds_exclusive_cv, &ds->ds_lock); 485 if (DSL_DATASET_IS_DESTROYED(ds)) { 486 mutex_exit(&ds->ds_lock); 487 dsl_dataset_drop_ref(ds, tag); 488 rw_enter(&dp->dp_config_rwlock, RW_READER); 489 return (ENOENT); 490 } 491 rw_enter(&dp->dp_config_rwlock, RW_READER); 492 } 493 mutex_exit(&ds->ds_lock); 494 return (0); 495 } 496 497 int 498 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag, 499 dsl_dataset_t **dsp) 500 { 501 int err = dsl_dataset_get_ref(dp, dsobj, tag, dsp); 502 503 if (err) 504 return (err); 505 return (dsl_dataset_hold_ref(*dsp, tag)); 506 } 507 508 int 509 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, int flags, void *owner, 510 dsl_dataset_t **dsp) 511 { 512 int err = dsl_dataset_hold_obj(dp, dsobj, owner, dsp); 513 514 ASSERT(DS_MODE_TYPE(flags) != DS_MODE_USER); 515 516 if (err) 517 return (err); 518 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 519 dsl_dataset_rele(*dsp, owner); 520 return (EBUSY); 521 } 522 return (0); 523 } 524 525 int 526 dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp) 527 { 528 dsl_dir_t *dd; 529 dsl_pool_t *dp; 530 const char *snapname; 531 uint64_t obj; 532 int err = 0; 533 534 err = dsl_dir_open_spa(NULL, name, FTAG, &dd, &snapname); 535 if (err) 536 return (err); 537 538 dp = dd->dd_pool; 539 obj = dd->dd_phys->dd_head_dataset_obj; 540 rw_enter(&dp->dp_config_rwlock, RW_READER); 541 if (obj) 542 err = dsl_dataset_get_ref(dp, obj, tag, dsp); 543 else 544 err = ENOENT; 545 if (err) 546 goto out; 547 548 err = dsl_dataset_hold_ref(*dsp, tag); 549 550 /* we may be looking for a snapshot */ 551 if (err == 0 && snapname != NULL) { 552 dsl_dataset_t *ds = NULL; 553 554 if (*snapname++ != '@') { 555 dsl_dataset_rele(*dsp, tag); 556 err = ENOENT; 557 goto out; 558 } 559 560 dprintf("looking for snapshot '%s'\n", snapname); 561 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj); 562 if (err == 0) 563 err = dsl_dataset_get_ref(dp, obj, tag, &ds); 564 dsl_dataset_rele(*dsp, tag); 565 566 ASSERT3U((err == 0), ==, (ds != NULL)); 567 568 if (ds) { 569 mutex_enter(&ds->ds_lock); 570 if (ds->ds_snapname[0] == 0) 571 (void) strlcpy(ds->ds_snapname, snapname, 572 sizeof (ds->ds_snapname)); 573 mutex_exit(&ds->ds_lock); 574 err = dsl_dataset_hold_ref(ds, tag); 575 *dsp = err ? NULL : ds; 576 } 577 } 578 out: 579 rw_exit(&dp->dp_config_rwlock); 580 dsl_dir_close(dd, FTAG); 581 return (err); 582 } 583 584 int 585 dsl_dataset_own(const char *name, int flags, void *owner, dsl_dataset_t **dsp) 586 { 587 int err = dsl_dataset_hold(name, owner, dsp); 588 if (err) 589 return (err); 590 if ((*dsp)->ds_phys->ds_num_children > 0 && 591 !DS_MODE_IS_READONLY(flags)) { 592 dsl_dataset_rele(*dsp, owner); 593 return (EROFS); 594 } 595 if (!dsl_dataset_tryown(*dsp, DS_MODE_IS_INCONSISTENT(flags), owner)) { 596 dsl_dataset_rele(*dsp, owner); 597 return (EBUSY); 598 } 599 return (0); 600 } 601 602 void 603 dsl_dataset_name(dsl_dataset_t *ds, char *name) 604 { 605 if (ds == NULL) { 606 (void) strcpy(name, "mos"); 607 } else { 608 dsl_dir_name(ds->ds_dir, name); 609 VERIFY(0 == dsl_dataset_get_snapname(ds)); 610 if (ds->ds_snapname[0]) { 611 (void) strcat(name, "@"); 612 /* 613 * We use a "recursive" mutex so that we 614 * can call dprintf_ds() with ds_lock held. 615 */ 616 if (!MUTEX_HELD(&ds->ds_lock)) { 617 mutex_enter(&ds->ds_lock); 618 (void) strcat(name, ds->ds_snapname); 619 mutex_exit(&ds->ds_lock); 620 } else { 621 (void) strcat(name, ds->ds_snapname); 622 } 623 } 624 } 625 } 626 627 static int 628 dsl_dataset_namelen(dsl_dataset_t *ds) 629 { 630 int result; 631 632 if (ds == NULL) { 633 result = 3; /* "mos" */ 634 } else { 635 result = dsl_dir_namelen(ds->ds_dir); 636 VERIFY(0 == dsl_dataset_get_snapname(ds)); 637 if (ds->ds_snapname[0]) { 638 ++result; /* adding one for the @-sign */ 639 if (!MUTEX_HELD(&ds->ds_lock)) { 640 mutex_enter(&ds->ds_lock); 641 result += strlen(ds->ds_snapname); 642 mutex_exit(&ds->ds_lock); 643 } else { 644 result += strlen(ds->ds_snapname); 645 } 646 } 647 } 648 649 return (result); 650 } 651 652 static void 653 dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag) 654 { 655 dmu_buf_rele(ds->ds_dbuf, tag); 656 } 657 658 void 659 dsl_dataset_rele(dsl_dataset_t *ds, void *tag) 660 { 661 ASSERT(ds->ds_owner != tag); 662 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) { 663 rw_exit(&ds->ds_rwlock); 664 } 665 dsl_dataset_drop_ref(ds, tag); 666 } 667 668 void 669 dsl_dataset_disown(dsl_dataset_t *ds, void *owner) 670 { 671 ASSERT((ds->ds_owner == owner && ds->ds_dbuf) || 672 (DSL_DATASET_IS_DESTROYED(ds) && ds->ds_dbuf == NULL)); 673 674 mutex_enter(&ds->ds_lock); 675 ds->ds_owner = NULL; 676 if (RW_WRITE_HELD(&ds->ds_rwlock)) { 677 rw_exit(&ds->ds_rwlock); 678 cv_broadcast(&ds->ds_exclusive_cv); 679 } 680 mutex_exit(&ds->ds_lock); 681 if (ds->ds_dbuf) 682 dsl_dataset_drop_ref(ds, owner); 683 else 684 dsl_dataset_evict(ds->ds_dbuf, ds); 685 } 686 687 boolean_t 688 dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok, void *owner) 689 { 690 boolean_t gotit = FALSE; 691 692 mutex_enter(&ds->ds_lock); 693 if (ds->ds_owner == NULL && 694 (!DS_IS_INCONSISTENT(ds) || inconsistentok)) { 695 ds->ds_owner = owner; 696 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) 697 rw_exit(&ds->ds_rwlock); 698 gotit = TRUE; 699 } 700 mutex_exit(&ds->ds_lock); 701 return (gotit); 702 } 703 704 void 705 dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *owner) 706 { 707 ASSERT3P(owner, ==, ds->ds_owner); 708 if (!RW_WRITE_HELD(&ds->ds_rwlock)) 709 rw_enter(&ds->ds_rwlock, RW_WRITER); 710 } 711 712 void 713 dsl_dataset_create_root(dsl_pool_t *dp, uint64_t *ddobjp, dmu_tx_t *tx) 714 { 715 objset_t *mos = dp->dp_meta_objset; 716 dmu_buf_t *dbuf; 717 dsl_dataset_phys_t *dsphys; 718 dsl_dataset_t *ds; 719 uint64_t dsobj; 720 dsl_dir_t *dd; 721 722 dsl_dir_create_root(mos, ddobjp, tx); 723 VERIFY(0 == dsl_dir_open_obj(dp, *ddobjp, NULL, FTAG, &dd)); 724 725 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 726 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 727 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 728 dmu_buf_will_dirty(dbuf, tx); 729 dsphys = dbuf->db_data; 730 dsphys->ds_dir_obj = dd->dd_object; 731 dsphys->ds_fsid_guid = unique_create(); 732 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 733 sizeof (dsphys->ds_guid)); 734 dsphys->ds_snapnames_zapobj = 735 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 736 DMU_OT_NONE, 0, tx); 737 dsphys->ds_creation_time = gethrestime_sec(); 738 dsphys->ds_creation_txg = tx->tx_txg; 739 dsphys->ds_deadlist_obj = 740 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 741 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 742 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 743 dmu_buf_rele(dbuf, FTAG); 744 745 dmu_buf_will_dirty(dd->dd_dbuf, tx); 746 dd->dd_phys->dd_head_dataset_obj = dsobj; 747 dsl_dir_close(dd, FTAG); 748 749 VERIFY(0 == dsl_dataset_get_ref(dp, dsobj, FTAG, &ds)); 750 (void) dmu_objset_create_impl(dp->dp_spa, ds, 751 &ds->ds_phys->ds_bp, DMU_OST_ZFS, tx); 752 dsl_dataset_drop_ref(ds, FTAG); 753 } 754 755 uint64_t 756 dsl_dataset_create_sync_impl(dsl_dir_t *dd, dsl_dataset_t *origin, 757 uint64_t flags, dmu_tx_t *tx) 758 { 759 dsl_pool_t *dp = dd->dd_pool; 760 dmu_buf_t *dbuf; 761 dsl_dataset_phys_t *dsphys; 762 uint64_t dsobj; 763 objset_t *mos = dp->dp_meta_objset; 764 765 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp); 766 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0); 767 ASSERT(dmu_tx_is_syncing(tx)); 768 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0); 769 770 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 771 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 772 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 773 dmu_buf_will_dirty(dbuf, tx); 774 dsphys = dbuf->db_data; 775 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 776 dsphys->ds_dir_obj = dd->dd_object; 777 dsphys->ds_flags = flags; 778 dsphys->ds_fsid_guid = unique_create(); 779 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 780 sizeof (dsphys->ds_guid)); 781 dsphys->ds_snapnames_zapobj = 782 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP, 783 DMU_OT_NONE, 0, tx); 784 dsphys->ds_creation_time = gethrestime_sec(); 785 dsphys->ds_creation_txg = tx->tx_txg; 786 dsphys->ds_deadlist_obj = 787 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 788 789 if (origin) { 790 dsphys->ds_prev_snap_obj = origin->ds_object; 791 dsphys->ds_prev_snap_txg = 792 origin->ds_phys->ds_creation_txg; 793 dsphys->ds_used_bytes = 794 origin->ds_phys->ds_used_bytes; 795 dsphys->ds_compressed_bytes = 796 origin->ds_phys->ds_compressed_bytes; 797 dsphys->ds_uncompressed_bytes = 798 origin->ds_phys->ds_uncompressed_bytes; 799 dsphys->ds_bp = origin->ds_phys->ds_bp; 800 dsphys->ds_flags |= origin->ds_phys->ds_flags; 801 802 dmu_buf_will_dirty(origin->ds_dbuf, tx); 803 origin->ds_phys->ds_num_children++; 804 805 dmu_buf_will_dirty(dd->dd_dbuf, tx); 806 dd->dd_phys->dd_origin_obj = origin->ds_object; 807 } 808 809 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 810 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 811 812 dmu_buf_rele(dbuf, FTAG); 813 814 dmu_buf_will_dirty(dd->dd_dbuf, tx); 815 dd->dd_phys->dd_head_dataset_obj = dsobj; 816 817 return (dsobj); 818 } 819 820 uint64_t 821 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname, 822 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx) 823 { 824 dsl_pool_t *dp = pdd->dd_pool; 825 uint64_t dsobj, ddobj; 826 dsl_dir_t *dd; 827 828 ASSERT(lastname[0] != '@'); 829 830 ddobj = dsl_dir_create_sync(pdd, lastname, tx); 831 VERIFY(0 == dsl_dir_open_obj(dp, ddobj, lastname, FTAG, &dd)); 832 833 dsobj = dsl_dataset_create_sync_impl(dd, origin, flags, tx); 834 835 dsl_deleg_set_create_perms(dd, tx, cr); 836 837 dsl_dir_close(dd, FTAG); 838 839 return (dsobj); 840 } 841 842 struct destroyarg { 843 dsl_sync_task_group_t *dstg; 844 char *snapname; 845 char *failed; 846 }; 847 848 static int 849 dsl_snapshot_destroy_one(char *name, void *arg) 850 { 851 struct destroyarg *da = arg; 852 dsl_dataset_t *ds; 853 char *cp; 854 int err; 855 856 (void) strcat(name, "@"); 857 (void) strcat(name, da->snapname); 858 err = dsl_dataset_own(name, DS_MODE_READONLY | DS_MODE_INCONSISTENT, 859 da->dstg, &ds); 860 cp = strchr(name, '@'); 861 *cp = '\0'; 862 if (err == 0) { 863 dsl_dataset_make_exclusive(ds, da->dstg); 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 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 934 dsl_dataset_destroy_check, dsl_dataset_destroy_sync, 935 ds, tag, 0); 936 goto out; 937 } 938 939 dd = ds->ds_dir; 940 941 /* 942 * Check for errors and mark this ds as inconsistent, in 943 * case we crash while freeing the objects. 944 */ 945 err = dsl_sync_task_do(dd->dd_pool, dsl_dataset_destroy_begin_check, 946 dsl_dataset_destroy_begin_sync, ds, NULL, 0); 947 if (err) 948 goto out; 949 950 err = dmu_objset_open_ds(ds, DMU_OST_ANY, &os); 951 if (err) 952 goto out; 953 954 /* 955 * remove the objects in open context, so that we won't 956 * have too much to do in syncing context. 957 */ 958 for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 959 ds->ds_phys->ds_prev_snap_txg)) { 960 dmu_tx_t *tx = dmu_tx_create(os); 961 dmu_tx_hold_free(tx, obj, 0, DMU_OBJECT_END); 962 dmu_tx_hold_bonus(tx, obj); 963 err = dmu_tx_assign(tx, TXG_WAIT); 964 if (err) { 965 /* 966 * Perhaps there is not enough disk 967 * space. Just deal with it from 968 * dsl_dataset_destroy_sync(). 969 */ 970 dmu_tx_abort(tx); 971 continue; 972 } 973 VERIFY(0 == dmu_object_free(os, obj, tx)); 974 dmu_tx_commit(tx); 975 } 976 977 dmu_objset_close(os); 978 if (err != ESRCH) 979 goto out; 980 981 if (ds->ds_user_ptr) { 982 /* 983 * We need to sync out all in-flight IO before we try 984 * to evict (the dataset evict func is trying to clear 985 * the cached entries for this dataset in the ARC). 986 */ 987 txg_wait_synced(dd->dd_pool, 0); 988 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 989 ds->ds_user_ptr = NULL; 990 } 991 992 rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER); 993 err = dsl_dir_open_obj(dd->dd_pool, dd->dd_object, NULL, FTAG, &dd); 994 rw_exit(&dd->dd_pool->dp_config_rwlock); 995 996 if (err) 997 goto out; 998 999 /* 1000 * Blow away the dsl_dir + head dataset. 1001 */ 1002 dsl_dataset_make_exclusive(ds, tag); 1003 dstg = dsl_sync_task_group_create(ds->ds_dir->dd_pool); 1004 dsl_sync_task_create(dstg, dsl_dataset_destroy_check, 1005 dsl_dataset_destroy_sync, ds, tag, 0); 1006 dsl_sync_task_create(dstg, dsl_dir_destroy_check, 1007 dsl_dir_destroy_sync, dd, FTAG, 0); 1008 err = dsl_sync_task_group_wait(dstg); 1009 dsl_sync_task_group_destroy(dstg); 1010 /* if it is successful, dsl_dir_destroy_sync will close the dd */ 1011 if (err) 1012 dsl_dir_close(dd, FTAG); 1013 out: 1014 dsl_dataset_disown(ds, tag); 1015 return (err); 1016 } 1017 1018 int 1019 dsl_dataset_rollback(dsl_dataset_t *ds, dmu_objset_type_t ost) 1020 { 1021 ASSERT(ds->ds_owner); 1022 1023 return (dsl_sync_task_do(ds->ds_dir->dd_pool, 1024 dsl_dataset_rollback_check, dsl_dataset_rollback_sync, 1025 ds, &ost, 0)); 1026 } 1027 1028 void * 1029 dsl_dataset_set_user_ptr(dsl_dataset_t *ds, 1030 void *p, dsl_dataset_evict_func_t func) 1031 { 1032 void *old; 1033 1034 mutex_enter(&ds->ds_lock); 1035 old = ds->ds_user_ptr; 1036 if (old == NULL) { 1037 ds->ds_user_ptr = p; 1038 ds->ds_user_evict_func = func; 1039 } 1040 mutex_exit(&ds->ds_lock); 1041 return (old); 1042 } 1043 1044 void * 1045 dsl_dataset_get_user_ptr(dsl_dataset_t *ds) 1046 { 1047 return (ds->ds_user_ptr); 1048 } 1049 1050 1051 blkptr_t * 1052 dsl_dataset_get_blkptr(dsl_dataset_t *ds) 1053 { 1054 return (&ds->ds_phys->ds_bp); 1055 } 1056 1057 void 1058 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx) 1059 { 1060 ASSERT(dmu_tx_is_syncing(tx)); 1061 /* If it's the meta-objset, set dp_meta_rootbp */ 1062 if (ds == NULL) { 1063 tx->tx_pool->dp_meta_rootbp = *bp; 1064 } else { 1065 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1066 ds->ds_phys->ds_bp = *bp; 1067 } 1068 } 1069 1070 spa_t * 1071 dsl_dataset_get_spa(dsl_dataset_t *ds) 1072 { 1073 return (ds->ds_dir->dd_pool->dp_spa); 1074 } 1075 1076 void 1077 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx) 1078 { 1079 dsl_pool_t *dp; 1080 1081 if (ds == NULL) /* this is the meta-objset */ 1082 return; 1083 1084 ASSERT(ds->ds_user_ptr != NULL); 1085 1086 if (ds->ds_phys->ds_next_snap_obj != 0) 1087 panic("dirtying snapshot!"); 1088 1089 dp = ds->ds_dir->dd_pool; 1090 1091 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg) == 0) { 1092 /* up the hold count until we can be written out */ 1093 dmu_buf_add_ref(ds->ds_dbuf, ds); 1094 } 1095 } 1096 1097 /* 1098 * The unique space in the head dataset can be calculated by subtracting 1099 * the space used in the most recent snapshot, that is still being used 1100 * in this file system, from the space currently in use. To figure out 1101 * the space in the most recent snapshot still in use, we need to take 1102 * the total space used in the snapshot and subtract out the space that 1103 * has been freed up since the snapshot was taken. 1104 */ 1105 static void 1106 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds) 1107 { 1108 uint64_t mrs_used; 1109 uint64_t dlused, dlcomp, dluncomp; 1110 1111 ASSERT(ds->ds_object == ds->ds_dir->dd_phys->dd_head_dataset_obj); 1112 1113 if (ds->ds_phys->ds_prev_snap_obj != 0) 1114 mrs_used = ds->ds_prev->ds_phys->ds_used_bytes; 1115 else 1116 mrs_used = 0; 1117 1118 VERIFY(0 == bplist_space(&ds->ds_deadlist, &dlused, &dlcomp, 1119 &dluncomp)); 1120 1121 ASSERT3U(dlused, <=, mrs_used); 1122 ds->ds_phys->ds_unique_bytes = 1123 ds->ds_phys->ds_used_bytes - (mrs_used - dlused); 1124 1125 if (!DS_UNIQUE_IS_ACCURATE(ds) && 1126 spa_version(ds->ds_dir->dd_pool->dp_spa) >= 1127 SPA_VERSION_UNIQUE_ACCURATE) 1128 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1129 } 1130 1131 static uint64_t 1132 dsl_dataset_unique(dsl_dataset_t *ds) 1133 { 1134 if (!DS_UNIQUE_IS_ACCURATE(ds) && !dsl_dataset_is_snapshot(ds)) 1135 dsl_dataset_recalc_head_uniq(ds); 1136 1137 return (ds->ds_phys->ds_unique_bytes); 1138 } 1139 1140 struct killarg { 1141 int64_t *usedp; 1142 int64_t *compressedp; 1143 int64_t *uncompressedp; 1144 zio_t *zio; 1145 dmu_tx_t *tx; 1146 }; 1147 1148 static int 1149 kill_blkptr(traverse_blk_cache_t *bc, spa_t *spa, void *arg) 1150 { 1151 struct killarg *ka = arg; 1152 blkptr_t *bp = &bc->bc_blkptr; 1153 1154 ASSERT3U(bc->bc_errno, ==, 0); 1155 1156 /* 1157 * Since this callback is not called concurrently, no lock is 1158 * needed on the accounting values. 1159 */ 1160 *ka->usedp += bp_get_dasize(spa, bp); 1161 *ka->compressedp += BP_GET_PSIZE(bp); 1162 *ka->uncompressedp += BP_GET_UCSIZE(bp); 1163 /* XXX check for EIO? */ 1164 (void) arc_free(ka->zio, spa, ka->tx->tx_txg, bp, NULL, NULL, 1165 ARC_NOWAIT); 1166 return (0); 1167 } 1168 1169 /* ARGSUSED */ 1170 static int 1171 dsl_dataset_rollback_check(void *arg1, void *arg2, dmu_tx_t *tx) 1172 { 1173 dsl_dataset_t *ds = arg1; 1174 dmu_objset_type_t *ost = arg2; 1175 1176 /* 1177 * We can only roll back to emptyness if it is a ZPL objset. 1178 */ 1179 if (*ost != DMU_OST_ZFS && ds->ds_phys->ds_prev_snap_txg == 0) 1180 return (EINVAL); 1181 1182 /* 1183 * This must not be a snapshot. 1184 */ 1185 if (ds->ds_phys->ds_next_snap_obj != 0) 1186 return (EINVAL); 1187 1188 /* 1189 * If we made changes this txg, traverse_dsl_dataset won't find 1190 * them. Try again. 1191 */ 1192 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1193 return (EAGAIN); 1194 1195 return (0); 1196 } 1197 1198 /* ARGSUSED */ 1199 static void 1200 dsl_dataset_rollback_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1201 { 1202 dsl_dataset_t *ds = arg1; 1203 dmu_objset_type_t *ost = arg2; 1204 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1205 1206 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1207 1208 /* 1209 * Before the roll back destroy the zil. 1210 */ 1211 if (ds->ds_user_ptr != NULL) { 1212 zil_rollback_destroy( 1213 ((objset_impl_t *)ds->ds_user_ptr)->os_zil, tx); 1214 1215 /* 1216 * We need to make sure that the objset_impl_t is reopened after 1217 * we do the rollback, otherwise it will have the wrong 1218 * objset_phys_t. Normally this would happen when this 1219 * dataset-open is closed, thus causing the 1220 * dataset to be immediately evicted. But when doing "zfs recv 1221 * -F", we reopen the objset before that, so that there is no 1222 * window where the dataset is closed and inconsistent. 1223 */ 1224 ds->ds_user_evict_func(ds, ds->ds_user_ptr); 1225 ds->ds_user_ptr = NULL; 1226 } 1227 1228 /* Zero out the deadlist. */ 1229 bplist_close(&ds->ds_deadlist); 1230 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1231 ds->ds_phys->ds_deadlist_obj = 1232 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1233 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1234 ds->ds_phys->ds_deadlist_obj)); 1235 1236 { 1237 /* Free blkptrs that we gave birth to */ 1238 zio_t *zio; 1239 int64_t used = 0, compressed = 0, uncompressed = 0; 1240 struct killarg ka; 1241 int64_t delta; 1242 1243 zio = zio_root(tx->tx_pool->dp_spa, NULL, NULL, 1244 ZIO_FLAG_MUSTSUCCEED); 1245 ka.usedp = &used; 1246 ka.compressedp = &compressed; 1247 ka.uncompressedp = &uncompressed; 1248 ka.zio = zio; 1249 ka.tx = tx; 1250 (void) traverse_dsl_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1251 ADVANCE_POST, kill_blkptr, &ka); 1252 (void) zio_wait(zio); 1253 1254 /* only deduct space beyond any refreservation */ 1255 delta = parent_delta(ds, -used); 1256 dsl_dir_diduse_space(ds->ds_dir, 1257 delta, -compressed, -uncompressed, tx); 1258 } 1259 1260 if (ds->ds_prev) { 1261 /* Change our contents to that of the prev snapshot */ 1262 ASSERT3U(ds->ds_prev->ds_object, ==, 1263 ds->ds_phys->ds_prev_snap_obj); 1264 ds->ds_phys->ds_bp = ds->ds_prev->ds_phys->ds_bp; 1265 ds->ds_phys->ds_used_bytes = 1266 ds->ds_prev->ds_phys->ds_used_bytes; 1267 ds->ds_phys->ds_compressed_bytes = 1268 ds->ds_prev->ds_phys->ds_compressed_bytes; 1269 ds->ds_phys->ds_uncompressed_bytes = 1270 ds->ds_prev->ds_phys->ds_uncompressed_bytes; 1271 ds->ds_phys->ds_flags = ds->ds_prev->ds_phys->ds_flags; 1272 ds->ds_phys->ds_unique_bytes = 0; 1273 1274 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1275 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1276 ds->ds_prev->ds_phys->ds_unique_bytes = 0; 1277 } 1278 } else { 1279 /* Zero out our contents, recreate objset */ 1280 bzero(&ds->ds_phys->ds_bp, sizeof (blkptr_t)); 1281 ds->ds_phys->ds_used_bytes = 0; 1282 ds->ds_phys->ds_compressed_bytes = 0; 1283 ds->ds_phys->ds_uncompressed_bytes = 0; 1284 ds->ds_phys->ds_flags = 0; 1285 ds->ds_phys->ds_unique_bytes = 0; 1286 (void) dmu_objset_create_impl(ds->ds_dir->dd_pool->dp_spa, ds, 1287 &ds->ds_phys->ds_bp, *ost, tx); 1288 } 1289 1290 spa_history_internal_log(LOG_DS_ROLLBACK, ds->ds_dir->dd_pool->dp_spa, 1291 tx, cr, "dataset = %llu", ds->ds_object); 1292 } 1293 1294 /* ARGSUSED */ 1295 static int 1296 dsl_dataset_destroy_begin_check(void *arg1, void *arg2, dmu_tx_t *tx) 1297 { 1298 dsl_dataset_t *ds = arg1; 1299 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; 1300 uint64_t count; 1301 int err; 1302 1303 /* 1304 * Can't delete a head dataset if there are snapshots of it. 1305 * (Except if the only snapshots are from the branch we cloned 1306 * from.) 1307 */ 1308 if (ds->ds_prev != NULL && 1309 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1310 return (EINVAL); 1311 1312 /* 1313 * This is really a dsl_dir thing, but check it here so that 1314 * we'll be less likely to leave this dataset inconsistent & 1315 * nearly destroyed. 1316 */ 1317 err = zap_count(mos, ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count); 1318 if (err) 1319 return (err); 1320 if (count != 0) 1321 return (EEXIST); 1322 1323 return (0); 1324 } 1325 1326 /* ARGSUSED */ 1327 static void 1328 dsl_dataset_destroy_begin_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1329 { 1330 dsl_dataset_t *ds = arg1; 1331 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1332 1333 /* Mark it as inconsistent on-disk, in case we crash */ 1334 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1335 ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT; 1336 1337 spa_history_internal_log(LOG_DS_DESTROY_BEGIN, dp->dp_spa, tx, 1338 cr, "dataset = %llu", ds->ds_object); 1339 } 1340 1341 /* ARGSUSED */ 1342 int 1343 dsl_dataset_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx) 1344 { 1345 dsl_dataset_t *ds = arg1; 1346 1347 /* we have an owner hold, so noone else can destroy us */ 1348 ASSERT(!DSL_DATASET_IS_DESTROYED(ds)); 1349 1350 /* Can't delete a branch point. */ 1351 if (ds->ds_phys->ds_num_children > 1) 1352 return (EEXIST); 1353 1354 /* 1355 * Can't delete a head dataset if there are snapshots of it. 1356 * (Except if the only snapshots are from the branch we cloned 1357 * from.) 1358 */ 1359 if (ds->ds_prev != NULL && 1360 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) 1361 return (EINVAL); 1362 1363 /* 1364 * If we made changes this txg, traverse_dsl_dataset won't find 1365 * them. Try again. 1366 */ 1367 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg) 1368 return (EAGAIN); 1369 1370 /* XXX we should do some i/o error checking... */ 1371 return (0); 1372 } 1373 1374 struct refsarg { 1375 kmutex_t lock; 1376 boolean_t gone; 1377 kcondvar_t cv; 1378 }; 1379 1380 /* ARGSUSED */ 1381 static void 1382 dsl_dataset_refs_gone(dmu_buf_t *db, void *argv) 1383 { 1384 struct refsarg *arg = argv; 1385 1386 mutex_enter(&arg->lock); 1387 arg->gone = TRUE; 1388 cv_signal(&arg->cv); 1389 mutex_exit(&arg->lock); 1390 } 1391 1392 static void 1393 dsl_dataset_drain_refs(dsl_dataset_t *ds, void *tag) 1394 { 1395 struct refsarg arg; 1396 1397 mutex_init(&arg.lock, NULL, MUTEX_DEFAULT, NULL); 1398 cv_init(&arg.cv, NULL, CV_DEFAULT, NULL); 1399 arg.gone = FALSE; 1400 (void) dmu_buf_update_user(ds->ds_dbuf, ds, &arg, &ds->ds_phys, 1401 dsl_dataset_refs_gone); 1402 dmu_buf_rele(ds->ds_dbuf, tag); 1403 mutex_enter(&arg.lock); 1404 while (!arg.gone) 1405 cv_wait(&arg.cv, &arg.lock); 1406 ASSERT(arg.gone); 1407 mutex_exit(&arg.lock); 1408 ds->ds_dbuf = NULL; 1409 ds->ds_phys = NULL; 1410 mutex_destroy(&arg.lock); 1411 cv_destroy(&arg.cv); 1412 } 1413 1414 void 1415 dsl_dataset_destroy_sync(void *arg1, void *tag, cred_t *cr, dmu_tx_t *tx) 1416 { 1417 dsl_dataset_t *ds = arg1; 1418 int64_t used = 0, compressed = 0, uncompressed = 0; 1419 zio_t *zio; 1420 int err; 1421 int after_branch_point = FALSE; 1422 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1423 objset_t *mos = dp->dp_meta_objset; 1424 dsl_dataset_t *ds_prev = NULL; 1425 uint64_t obj; 1426 1427 ASSERT(ds->ds_owner); 1428 ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); 1429 ASSERT(ds->ds_prev == NULL || 1430 ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object); 1431 ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); 1432 1433 /* signal any waiters that this dataset is going away */ 1434 mutex_enter(&ds->ds_lock); 1435 ds->ds_owner = dsl_reaper; 1436 cv_broadcast(&ds->ds_exclusive_cv); 1437 mutex_exit(&ds->ds_lock); 1438 1439 /* Remove our reservation */ 1440 if (ds->ds_reserved != 0) { 1441 uint64_t val = 0; 1442 dsl_dataset_set_reservation_sync(ds, &val, cr, tx); 1443 ASSERT3U(ds->ds_reserved, ==, 0); 1444 } 1445 1446 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1447 1448 obj = ds->ds_object; 1449 1450 if (ds->ds_phys->ds_prev_snap_obj != 0) { 1451 if (ds->ds_prev) { 1452 ds_prev = ds->ds_prev; 1453 } else { 1454 VERIFY(0 == dsl_dataset_hold_obj(dp, 1455 ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev)); 1456 } 1457 after_branch_point = 1458 (ds_prev->ds_phys->ds_next_snap_obj != obj); 1459 1460 dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); 1461 if (after_branch_point && 1462 ds->ds_phys->ds_next_snap_obj == 0) { 1463 /* This clone is toast. */ 1464 ASSERT(ds_prev->ds_phys->ds_num_children > 1); 1465 ds_prev->ds_phys->ds_num_children--; 1466 } else if (!after_branch_point) { 1467 ds_prev->ds_phys->ds_next_snap_obj = 1468 ds->ds_phys->ds_next_snap_obj; 1469 } 1470 } 1471 1472 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 1473 1474 if (ds->ds_phys->ds_next_snap_obj != 0) { 1475 blkptr_t bp; 1476 dsl_dataset_t *ds_next; 1477 uint64_t itor = 0; 1478 uint64_t old_unique; 1479 1480 spa_scrub_restart(dp->dp_spa, tx->tx_txg); 1481 1482 VERIFY(0 == dsl_dataset_hold_obj(dp, 1483 ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next)); 1484 ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj); 1485 1486 old_unique = dsl_dataset_unique(ds_next); 1487 1488 dmu_buf_will_dirty(ds_next->ds_dbuf, tx); 1489 ds_next->ds_phys->ds_prev_snap_obj = 1490 ds->ds_phys->ds_prev_snap_obj; 1491 ds_next->ds_phys->ds_prev_snap_txg = 1492 ds->ds_phys->ds_prev_snap_txg; 1493 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1494 ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0); 1495 1496 /* 1497 * Transfer to our deadlist (which will become next's 1498 * new deadlist) any entries from next's current 1499 * deadlist which were born before prev, and free the 1500 * other entries. 1501 * 1502 * XXX we're doing this long task with the config lock held 1503 */ 1504 while (bplist_iterate(&ds_next->ds_deadlist, &itor, &bp) == 0) { 1505 if (bp.blk_birth <= ds->ds_phys->ds_prev_snap_txg) { 1506 VERIFY(0 == bplist_enqueue(&ds->ds_deadlist, 1507 &bp, tx)); 1508 if (ds_prev && !after_branch_point && 1509 bp.blk_birth > 1510 ds_prev->ds_phys->ds_prev_snap_txg) { 1511 ds_prev->ds_phys->ds_unique_bytes += 1512 bp_get_dasize(dp->dp_spa, &bp); 1513 } 1514 } else { 1515 used += bp_get_dasize(dp->dp_spa, &bp); 1516 compressed += BP_GET_PSIZE(&bp); 1517 uncompressed += BP_GET_UCSIZE(&bp); 1518 /* XXX check return value? */ 1519 (void) arc_free(zio, dp->dp_spa, tx->tx_txg, 1520 &bp, NULL, NULL, ARC_NOWAIT); 1521 } 1522 } 1523 1524 /* free next's deadlist */ 1525 bplist_close(&ds_next->ds_deadlist); 1526 bplist_destroy(mos, ds_next->ds_phys->ds_deadlist_obj, tx); 1527 1528 /* set next's deadlist to our deadlist */ 1529 bplist_close(&ds->ds_deadlist); 1530 ds_next->ds_phys->ds_deadlist_obj = 1531 ds->ds_phys->ds_deadlist_obj; 1532 VERIFY(0 == bplist_open(&ds_next->ds_deadlist, mos, 1533 ds_next->ds_phys->ds_deadlist_obj)); 1534 ds->ds_phys->ds_deadlist_obj = 0; 1535 1536 if (ds_next->ds_phys->ds_next_snap_obj != 0) { 1537 /* 1538 * Update next's unique to include blocks which 1539 * were previously shared by only this snapshot 1540 * and it. Those blocks will be born after the 1541 * prev snap and before this snap, and will have 1542 * died after the next snap and before the one 1543 * after that (ie. be on the snap after next's 1544 * deadlist). 1545 * 1546 * XXX we're doing this long task with the 1547 * config lock held 1548 */ 1549 dsl_dataset_t *ds_after_next; 1550 1551 VERIFY(0 == dsl_dataset_hold_obj(dp, 1552 ds_next->ds_phys->ds_next_snap_obj, 1553 FTAG, &ds_after_next)); 1554 itor = 0; 1555 while (bplist_iterate(&ds_after_next->ds_deadlist, 1556 &itor, &bp) == 0) { 1557 if (bp.blk_birth > 1558 ds->ds_phys->ds_prev_snap_txg && 1559 bp.blk_birth <= 1560 ds->ds_phys->ds_creation_txg) { 1561 ds_next->ds_phys->ds_unique_bytes += 1562 bp_get_dasize(dp->dp_spa, &bp); 1563 } 1564 } 1565 1566 dsl_dataset_rele(ds_after_next, FTAG); 1567 ASSERT3P(ds_next->ds_prev, ==, NULL); 1568 } else { 1569 ASSERT3P(ds_next->ds_prev, ==, ds); 1570 dsl_dataset_drop_ref(ds_next->ds_prev, ds_next); 1571 ds_next->ds_prev = NULL; 1572 if (ds_prev) { 1573 VERIFY(0 == dsl_dataset_get_ref(dp, 1574 ds->ds_phys->ds_prev_snap_obj, 1575 ds_next, &ds_next->ds_prev)); 1576 } 1577 1578 dsl_dataset_recalc_head_uniq(ds_next); 1579 1580 /* 1581 * Reduce the amount of our unconsmed refreservation 1582 * being charged to our parent by the amount of 1583 * new unique data we have gained. 1584 */ 1585 if (old_unique < ds_next->ds_reserved) { 1586 int64_t mrsdelta; 1587 uint64_t new_unique = 1588 ds_next->ds_phys->ds_unique_bytes; 1589 1590 ASSERT(old_unique <= new_unique); 1591 mrsdelta = MIN(new_unique - old_unique, 1592 ds_next->ds_reserved - old_unique); 1593 dsl_dir_diduse_space(ds->ds_dir, -mrsdelta, 1594 0, 0, tx); 1595 } 1596 } 1597 dsl_dataset_rele(ds_next, FTAG); 1598 1599 /* 1600 * NB: unique_bytes might not be accurate for the head objset. 1601 * Before SPA_VERSION 9, we didn't update its value when we 1602 * deleted the most recent snapshot. 1603 */ 1604 ASSERT3U(used, ==, ds->ds_phys->ds_unique_bytes); 1605 } else { 1606 /* 1607 * There's no next snapshot, so this is a head dataset. 1608 * Destroy the deadlist. Unless it's a clone, the 1609 * deadlist should be empty. (If it's a clone, it's 1610 * safe to ignore the deadlist contents.) 1611 */ 1612 struct killarg ka; 1613 1614 ASSERT(after_branch_point || bplist_empty(&ds->ds_deadlist)); 1615 bplist_close(&ds->ds_deadlist); 1616 bplist_destroy(mos, ds->ds_phys->ds_deadlist_obj, tx); 1617 ds->ds_phys->ds_deadlist_obj = 0; 1618 1619 /* 1620 * Free everything that we point to (that's born after 1621 * the previous snapshot, if we are a clone) 1622 * 1623 * XXX we're doing this long task with the config lock held 1624 */ 1625 ka.usedp = &used; 1626 ka.compressedp = &compressed; 1627 ka.uncompressedp = &uncompressed; 1628 ka.zio = zio; 1629 ka.tx = tx; 1630 err = traverse_dsl_dataset(ds, ds->ds_phys->ds_prev_snap_txg, 1631 ADVANCE_POST, kill_blkptr, &ka); 1632 ASSERT3U(err, ==, 0); 1633 ASSERT(spa_version(dp->dp_spa) < 1634 SPA_VERSION_UNIQUE_ACCURATE || 1635 used == ds->ds_phys->ds_unique_bytes); 1636 } 1637 1638 err = zio_wait(zio); 1639 ASSERT3U(err, ==, 0); 1640 1641 dsl_dir_diduse_space(ds->ds_dir, -used, -compressed, -uncompressed, tx); 1642 1643 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == ds->ds_object) { 1644 /* Erase the link in the dir */ 1645 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); 1646 ds->ds_dir->dd_phys->dd_head_dataset_obj = 0; 1647 ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0); 1648 err = zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx); 1649 ASSERT(err == 0); 1650 } else { 1651 /* remove from snapshot namespace */ 1652 dsl_dataset_t *ds_head; 1653 ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0); 1654 VERIFY(0 == dsl_dataset_hold_obj(dp, 1655 ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head)); 1656 VERIFY(0 == dsl_dataset_get_snapname(ds)); 1657 #ifdef ZFS_DEBUG 1658 { 1659 uint64_t val; 1660 1661 err = dsl_dataset_snap_lookup(ds_head, 1662 ds->ds_snapname, &val); 1663 ASSERT3U(err, ==, 0); 1664 ASSERT3U(val, ==, obj); 1665 } 1666 #endif 1667 err = dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx); 1668 ASSERT(err == 0); 1669 dsl_dataset_rele(ds_head, FTAG); 1670 } 1671 1672 if (ds_prev && ds->ds_prev != ds_prev) 1673 dsl_dataset_rele(ds_prev, FTAG); 1674 1675 spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); 1676 spa_history_internal_log(LOG_DS_DESTROY, dp->dp_spa, tx, 1677 cr, "dataset = %llu", ds->ds_object); 1678 1679 dsl_dir_close(ds->ds_dir, ds); 1680 ds->ds_dir = NULL; 1681 dsl_dataset_drain_refs(ds, tag); 1682 VERIFY(0 == dmu_object_free(mos, obj, tx)); 1683 } 1684 1685 static int 1686 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx) 1687 { 1688 uint64_t asize; 1689 1690 if (!dmu_tx_is_syncing(tx)) 1691 return (0); 1692 1693 /* 1694 * If there's an fs-only reservation, any blocks that might become 1695 * owned by the snapshot dataset must be accommodated by space 1696 * outside of the reservation. 1697 */ 1698 asize = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1699 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, FALSE)) 1700 return (ENOSPC); 1701 1702 /* 1703 * Propogate any reserved space for this snapshot to other 1704 * snapshot checks in this sync group. 1705 */ 1706 if (asize > 0) 1707 dsl_dir_willuse_space(ds->ds_dir, asize, tx); 1708 1709 return (0); 1710 } 1711 1712 /* ARGSUSED */ 1713 int 1714 dsl_dataset_snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx) 1715 { 1716 dsl_dataset_t *ds = arg1; 1717 const char *snapname = arg2; 1718 int err; 1719 uint64_t value; 1720 1721 /* 1722 * We don't allow multiple snapshots of the same txg. If there 1723 * is already one, try again. 1724 */ 1725 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg) 1726 return (EAGAIN); 1727 1728 /* 1729 * Check for conflicting name snapshot name. 1730 */ 1731 err = dsl_dataset_snap_lookup(ds, snapname, &value); 1732 if (err == 0) 1733 return (EEXIST); 1734 if (err != ENOENT) 1735 return (err); 1736 1737 /* 1738 * Check that the dataset's name is not too long. Name consists 1739 * of the dataset's length + 1 for the @-sign + snapshot name's length 1740 */ 1741 if (dsl_dataset_namelen(ds) + 1 + strlen(snapname) >= MAXNAMELEN) 1742 return (ENAMETOOLONG); 1743 1744 err = dsl_dataset_snapshot_reserve_space(ds, tx); 1745 if (err) 1746 return (err); 1747 1748 ds->ds_trysnap_txg = tx->tx_txg; 1749 return (0); 1750 } 1751 1752 void 1753 dsl_dataset_snapshot_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 1754 { 1755 dsl_dataset_t *ds = arg1; 1756 const char *snapname = arg2; 1757 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1758 dmu_buf_t *dbuf; 1759 dsl_dataset_phys_t *dsphys; 1760 uint64_t dsobj; 1761 objset_t *mos = dp->dp_meta_objset; 1762 int err; 1763 1764 spa_scrub_restart(dp->dp_spa, tx->tx_txg); 1765 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock)); 1766 1767 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0, 1768 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx); 1769 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf)); 1770 dmu_buf_will_dirty(dbuf, tx); 1771 dsphys = dbuf->db_data; 1772 bzero(dsphys, sizeof (dsl_dataset_phys_t)); 1773 dsphys->ds_dir_obj = ds->ds_dir->dd_object; 1774 dsphys->ds_fsid_guid = unique_create(); 1775 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid, 1776 sizeof (dsphys->ds_guid)); 1777 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj; 1778 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg; 1779 dsphys->ds_next_snap_obj = ds->ds_object; 1780 dsphys->ds_num_children = 1; 1781 dsphys->ds_creation_time = gethrestime_sec(); 1782 dsphys->ds_creation_txg = tx->tx_txg; 1783 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj; 1784 dsphys->ds_used_bytes = ds->ds_phys->ds_used_bytes; 1785 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes; 1786 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes; 1787 dsphys->ds_flags = ds->ds_phys->ds_flags; 1788 dsphys->ds_bp = ds->ds_phys->ds_bp; 1789 dmu_buf_rele(dbuf, FTAG); 1790 1791 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0); 1792 if (ds->ds_prev) { 1793 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj == 1794 ds->ds_object || 1795 ds->ds_prev->ds_phys->ds_num_children > 1); 1796 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) { 1797 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); 1798 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, 1799 ds->ds_prev->ds_phys->ds_creation_txg); 1800 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj; 1801 } 1802 } 1803 1804 /* 1805 * If we have a reference-reservation on this dataset, we will 1806 * need to increase the amount of refreservation being charged 1807 * since our unique space is going to zero. 1808 */ 1809 if (ds->ds_reserved) { 1810 int64_t add = MIN(dsl_dataset_unique(ds), ds->ds_reserved); 1811 dsl_dir_diduse_space(ds->ds_dir, add, 0, 0, tx); 1812 } 1813 1814 bplist_close(&ds->ds_deadlist); 1815 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1816 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg); 1817 ds->ds_phys->ds_prev_snap_obj = dsobj; 1818 ds->ds_phys->ds_prev_snap_txg = tx->tx_txg; 1819 ds->ds_phys->ds_unique_bytes = 0; 1820 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE) 1821 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE; 1822 ds->ds_phys->ds_deadlist_obj = 1823 bplist_create(mos, DSL_DEADLIST_BLOCKSIZE, tx); 1824 VERIFY(0 == bplist_open(&ds->ds_deadlist, mos, 1825 ds->ds_phys->ds_deadlist_obj)); 1826 1827 dprintf("snap '%s' -> obj %llu\n", snapname, dsobj); 1828 err = zap_add(mos, ds->ds_phys->ds_snapnames_zapobj, 1829 snapname, 8, 1, &dsobj, tx); 1830 ASSERT(err == 0); 1831 1832 if (ds->ds_prev) 1833 dsl_dataset_drop_ref(ds->ds_prev, ds); 1834 VERIFY(0 == dsl_dataset_get_ref(dp, 1835 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 1836 1837 spa_history_internal_log(LOG_DS_SNAPSHOT, dp->dp_spa, tx, cr, 1838 "dataset = %llu", dsobj); 1839 } 1840 1841 void 1842 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx) 1843 { 1844 ASSERT(dmu_tx_is_syncing(tx)); 1845 ASSERT(ds->ds_user_ptr != NULL); 1846 ASSERT(ds->ds_phys->ds_next_snap_obj == 0); 1847 1848 /* 1849 * in case we had to change ds_fsid_guid when we opened it, 1850 * sync it out now. 1851 */ 1852 dmu_buf_will_dirty(ds->ds_dbuf, tx); 1853 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid; 1854 1855 dsl_dir_dirty(ds->ds_dir, tx); 1856 dmu_objset_sync(ds->ds_user_ptr, zio, tx); 1857 } 1858 1859 void 1860 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv) 1861 { 1862 uint64_t refd, avail, uobjs, aobjs; 1863 1864 dsl_dir_stats(ds->ds_dir, nv); 1865 1866 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs); 1867 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail); 1868 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd); 1869 1870 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION, 1871 ds->ds_phys->ds_creation_time); 1872 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG, 1873 ds->ds_phys->ds_creation_txg); 1874 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA, 1875 ds->ds_quota); 1876 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION, 1877 ds->ds_reserved); 1878 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID, 1879 ds->ds_phys->ds_guid); 1880 1881 if (ds->ds_phys->ds_next_snap_obj) { 1882 /* 1883 * This is a snapshot; override the dd's space used with 1884 * our unique space and compression ratio. 1885 */ 1886 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, 1887 ds->ds_phys->ds_unique_bytes); 1888 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, 1889 ds->ds_phys->ds_compressed_bytes == 0 ? 100 : 1890 (ds->ds_phys->ds_uncompressed_bytes * 100 / 1891 ds->ds_phys->ds_compressed_bytes)); 1892 } 1893 } 1894 1895 void 1896 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat) 1897 { 1898 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg; 1899 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT; 1900 stat->dds_guid = ds->ds_phys->ds_guid; 1901 if (ds->ds_phys->ds_next_snap_obj) { 1902 stat->dds_is_snapshot = B_TRUE; 1903 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1; 1904 } 1905 1906 /* clone origin is really a dsl_dir thing... */ 1907 rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER); 1908 if (ds->ds_dir->dd_phys->dd_origin_obj) { 1909 dsl_dataset_t *ods; 1910 1911 VERIFY(0 == dsl_dataset_get_ref(ds->ds_dir->dd_pool, 1912 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods)); 1913 dsl_dataset_name(ods, stat->dds_origin); 1914 dsl_dataset_drop_ref(ods, FTAG); 1915 } 1916 rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock); 1917 } 1918 1919 uint64_t 1920 dsl_dataset_fsid_guid(dsl_dataset_t *ds) 1921 { 1922 return (ds->ds_fsid_guid); 1923 } 1924 1925 void 1926 dsl_dataset_space(dsl_dataset_t *ds, 1927 uint64_t *refdbytesp, uint64_t *availbytesp, 1928 uint64_t *usedobjsp, uint64_t *availobjsp) 1929 { 1930 *refdbytesp = ds->ds_phys->ds_used_bytes; 1931 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE); 1932 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) 1933 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes; 1934 if (ds->ds_quota != 0) { 1935 /* 1936 * Adjust available bytes according to refquota 1937 */ 1938 if (*refdbytesp < ds->ds_quota) 1939 *availbytesp = MIN(*availbytesp, 1940 ds->ds_quota - *refdbytesp); 1941 else 1942 *availbytesp = 0; 1943 } 1944 *usedobjsp = ds->ds_phys->ds_bp.blk_fill; 1945 *availobjsp = DN_MAX_OBJECT - *usedobjsp; 1946 } 1947 1948 boolean_t 1949 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds) 1950 { 1951 dsl_pool_t *dp = ds->ds_dir->dd_pool; 1952 1953 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) || 1954 dsl_pool_sync_context(dp)); 1955 if (ds->ds_prev == NULL) 1956 return (B_FALSE); 1957 if (ds->ds_phys->ds_bp.blk_birth > 1958 ds->ds_prev->ds_phys->ds_creation_txg) 1959 return (B_TRUE); 1960 return (B_FALSE); 1961 } 1962 1963 /* ARGSUSED */ 1964 static int 1965 dsl_dataset_snapshot_rename_check(void *arg1, void *arg2, dmu_tx_t *tx) 1966 { 1967 dsl_dataset_t *ds = arg1; 1968 char *newsnapname = arg2; 1969 dsl_dir_t *dd = ds->ds_dir; 1970 dsl_dataset_t *hds; 1971 uint64_t val; 1972 int err; 1973 1974 err = dsl_dataset_hold_obj(dd->dd_pool, 1975 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds); 1976 if (err) 1977 return (err); 1978 1979 /* new name better not be in use */ 1980 err = dsl_dataset_snap_lookup(hds, newsnapname, &val); 1981 dsl_dataset_rele(hds, FTAG); 1982 1983 if (err == 0) 1984 err = EEXIST; 1985 else if (err == ENOENT) 1986 err = 0; 1987 1988 /* dataset name + 1 for the "@" + the new snapshot name must fit */ 1989 if (dsl_dir_namelen(ds->ds_dir) + 1 + strlen(newsnapname) >= MAXNAMELEN) 1990 err = ENAMETOOLONG; 1991 1992 return (err); 1993 } 1994 1995 static void 1996 dsl_dataset_snapshot_rename_sync(void *arg1, void *arg2, 1997 cred_t *cr, dmu_tx_t *tx) 1998 { 1999 dsl_dataset_t *ds = arg1; 2000 const char *newsnapname = arg2; 2001 dsl_dir_t *dd = ds->ds_dir; 2002 objset_t *mos = dd->dd_pool->dp_meta_objset; 2003 dsl_dataset_t *hds; 2004 int err; 2005 2006 ASSERT(ds->ds_phys->ds_next_snap_obj != 0); 2007 2008 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, 2009 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds)); 2010 2011 VERIFY(0 == dsl_dataset_get_snapname(ds)); 2012 err = dsl_dataset_snap_remove(hds, ds->ds_snapname, tx); 2013 ASSERT3U(err, ==, 0); 2014 mutex_enter(&ds->ds_lock); 2015 (void) strcpy(ds->ds_snapname, newsnapname); 2016 mutex_exit(&ds->ds_lock); 2017 err = zap_add(mos, hds->ds_phys->ds_snapnames_zapobj, 2018 ds->ds_snapname, 8, 1, &ds->ds_object, tx); 2019 ASSERT3U(err, ==, 0); 2020 2021 spa_history_internal_log(LOG_DS_RENAME, dd->dd_pool->dp_spa, tx, 2022 cr, "dataset = %llu", ds->ds_object); 2023 dsl_dataset_rele(hds, FTAG); 2024 } 2025 2026 struct renamesnaparg { 2027 dsl_sync_task_group_t *dstg; 2028 char failed[MAXPATHLEN]; 2029 char *oldsnap; 2030 char *newsnap; 2031 }; 2032 2033 static int 2034 dsl_snapshot_rename_one(char *name, void *arg) 2035 { 2036 struct renamesnaparg *ra = arg; 2037 dsl_dataset_t *ds = NULL; 2038 char *cp; 2039 int err; 2040 2041 cp = name + strlen(name); 2042 *cp = '@'; 2043 (void) strcpy(cp + 1, ra->oldsnap); 2044 2045 /* 2046 * For recursive snapshot renames the parent won't be changing 2047 * so we just pass name for both the to/from argument. 2048 */ 2049 if (err = zfs_secpolicy_rename_perms(name, name, CRED())) { 2050 (void) strcpy(ra->failed, name); 2051 return (err); 2052 } 2053 2054 #ifdef _KERNEL 2055 /* 2056 * For all filesystems undergoing rename, we'll need to unmount it. 2057 */ 2058 (void) zfs_unmount_snap(name, NULL); 2059 #endif 2060 err = dsl_dataset_hold(name, ra->dstg, &ds); 2061 *cp = '\0'; 2062 if (err == ENOENT) { 2063 return (0); 2064 } else if (err) { 2065 (void) strcpy(ra->failed, name); 2066 return (err); 2067 } 2068 2069 dsl_sync_task_create(ra->dstg, dsl_dataset_snapshot_rename_check, 2070 dsl_dataset_snapshot_rename_sync, ds, ra->newsnap, 0); 2071 2072 return (0); 2073 } 2074 2075 static int 2076 dsl_recursive_rename(char *oldname, const char *newname) 2077 { 2078 int err; 2079 struct renamesnaparg *ra; 2080 dsl_sync_task_t *dst; 2081 spa_t *spa; 2082 char *cp, *fsname = spa_strdup(oldname); 2083 int len = strlen(oldname); 2084 2085 /* truncate the snapshot name to get the fsname */ 2086 cp = strchr(fsname, '@'); 2087 *cp = '\0'; 2088 2089 err = spa_open(fsname, &spa, FTAG); 2090 if (err) { 2091 kmem_free(fsname, len + 1); 2092 return (err); 2093 } 2094 ra = kmem_alloc(sizeof (struct renamesnaparg), KM_SLEEP); 2095 ra->dstg = dsl_sync_task_group_create(spa_get_dsl(spa)); 2096 2097 ra->oldsnap = strchr(oldname, '@') + 1; 2098 ra->newsnap = strchr(newname, '@') + 1; 2099 *ra->failed = '\0'; 2100 2101 err = dmu_objset_find(fsname, dsl_snapshot_rename_one, ra, 2102 DS_FIND_CHILDREN); 2103 kmem_free(fsname, len + 1); 2104 2105 if (err == 0) { 2106 err = dsl_sync_task_group_wait(ra->dstg); 2107 } 2108 2109 for (dst = list_head(&ra->dstg->dstg_tasks); dst; 2110 dst = list_next(&ra->dstg->dstg_tasks, dst)) { 2111 dsl_dataset_t *ds = dst->dst_arg1; 2112 if (dst->dst_err) { 2113 dsl_dir_name(ds->ds_dir, ra->failed); 2114 (void) strcat(ra->failed, "@"); 2115 (void) strcat(ra->failed, ra->newsnap); 2116 } 2117 dsl_dataset_rele(ds, ra->dstg); 2118 } 2119 2120 if (err) 2121 (void) strcpy(oldname, ra->failed); 2122 2123 dsl_sync_task_group_destroy(ra->dstg); 2124 kmem_free(ra, sizeof (struct renamesnaparg)); 2125 spa_close(spa, FTAG); 2126 return (err); 2127 } 2128 2129 static int 2130 dsl_valid_rename(char *oldname, void *arg) 2131 { 2132 int delta = *(int *)arg; 2133 2134 if (strlen(oldname) + delta >= MAXNAMELEN) 2135 return (ENAMETOOLONG); 2136 2137 return (0); 2138 } 2139 2140 #pragma weak dmu_objset_rename = dsl_dataset_rename 2141 int 2142 dsl_dataset_rename(char *oldname, const char *newname, boolean_t recursive) 2143 { 2144 dsl_dir_t *dd; 2145 dsl_dataset_t *ds; 2146 const char *tail; 2147 int err; 2148 2149 err = dsl_dir_open(oldname, FTAG, &dd, &tail); 2150 if (err) 2151 return (err); 2152 if (tail == NULL) { 2153 int delta = strlen(newname) - strlen(oldname); 2154 2155 /* if we're growing, validate child size lengths */ 2156 if (delta > 0) 2157 err = dmu_objset_find(oldname, dsl_valid_rename, 2158 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS); 2159 2160 if (!err) 2161 err = dsl_dir_rename(dd, newname); 2162 dsl_dir_close(dd, FTAG); 2163 return (err); 2164 } 2165 if (tail[0] != '@') { 2166 /* the name ended in a nonexistant component */ 2167 dsl_dir_close(dd, FTAG); 2168 return (ENOENT); 2169 } 2170 2171 dsl_dir_close(dd, FTAG); 2172 2173 /* new name must be snapshot in same filesystem */ 2174 tail = strchr(newname, '@'); 2175 if (tail == NULL) 2176 return (EINVAL); 2177 tail++; 2178 if (strncmp(oldname, newname, tail - newname) != 0) 2179 return (EXDEV); 2180 2181 if (recursive) { 2182 err = dsl_recursive_rename(oldname, newname); 2183 } else { 2184 err = dsl_dataset_hold(oldname, FTAG, &ds); 2185 if (err) 2186 return (err); 2187 2188 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2189 dsl_dataset_snapshot_rename_check, 2190 dsl_dataset_snapshot_rename_sync, ds, (char *)tail, 1); 2191 2192 dsl_dataset_rele(ds, FTAG); 2193 } 2194 2195 return (err); 2196 } 2197 2198 struct promotedsarg { 2199 list_node_t link; 2200 dsl_dataset_t *ds; 2201 }; 2202 2203 struct promotearg { 2204 list_t snap_list; 2205 dsl_dataset_t *clone_origin, *old_head; 2206 uint64_t used, comp, uncomp, unique; 2207 uint64_t newnext_obj; 2208 }; 2209 2210 /* ARGSUSED */ 2211 static int 2212 dsl_dataset_promote_check(void *arg1, void *arg2, dmu_tx_t *tx) 2213 { 2214 dsl_dataset_t *hds = arg1; 2215 struct promotearg *pa = arg2; 2216 struct promotedsarg *snap = list_head(&pa->snap_list); 2217 dsl_pool_t *dp = hds->ds_dir->dd_pool; 2218 dsl_dataset_t *origin_ds = snap->ds; 2219 dsl_dataset_t *newnext_ds; 2220 char *name; 2221 uint64_t itor = 0; 2222 blkptr_t bp; 2223 int err; 2224 2225 /* Check that it is a clone */ 2226 if (hds->ds_dir->dd_phys->dd_origin_obj == 0) 2227 return (EINVAL); 2228 2229 /* Since this is so expensive, don't do the preliminary check */ 2230 if (!dmu_tx_is_syncing(tx)) 2231 return (0); 2232 2233 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) 2234 return (EXDEV); 2235 2236 /* find origin's new next ds */ 2237 newnext_ds = hds; 2238 while (newnext_ds->ds_phys->ds_prev_snap_obj != origin_ds->ds_object) { 2239 dsl_dataset_t *prev; 2240 2241 err = dsl_dataset_hold_obj(dp, 2242 newnext_ds->ds_phys->ds_prev_snap_obj, FTAG, &prev); 2243 if (newnext_ds != hds) 2244 dsl_dataset_rele(newnext_ds, FTAG); 2245 if (err) 2246 return (err); 2247 newnext_ds = prev; 2248 } 2249 pa->newnext_obj = newnext_ds->ds_object; 2250 2251 /* compute origin's new unique space */ 2252 pa->unique = 0; 2253 while ((err = bplist_iterate(&newnext_ds->ds_deadlist, 2254 &itor, &bp)) == 0) { 2255 if (bp.blk_birth > origin_ds->ds_phys->ds_prev_snap_txg) 2256 pa->unique += bp_get_dasize(dp->dp_spa, &bp); 2257 } 2258 if (newnext_ds != hds) 2259 dsl_dataset_rele(newnext_ds, FTAG); 2260 if (err != ENOENT) 2261 return (err); 2262 2263 name = kmem_alloc(MAXPATHLEN, KM_SLEEP); 2264 2265 /* 2266 * Walk the snapshots that we are moving 2267 * 2268 * Compute space to transfer. Each snapshot gave birth to: 2269 * (my used) - (prev's used) + (deadlist's used) 2270 * So a sequence would look like: 2271 * uN - u(N-1) + dN + ... + u1 - u0 + d1 + u0 - 0 + d0 2272 * Which simplifies to: 2273 * uN + dN + ... + d1 + d0 2274 * Note however, if we stop before we reach the ORIGIN we get: 2275 * uN + dN + ... + dM - uM-1 2276 */ 2277 pa->used = origin_ds->ds_phys->ds_used_bytes; 2278 pa->comp = origin_ds->ds_phys->ds_compressed_bytes; 2279 pa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes; 2280 do { 2281 uint64_t val, dlused, dlcomp, dluncomp; 2282 dsl_dataset_t *ds = snap->ds; 2283 2284 /* Check that the snapshot name does not conflict */ 2285 dsl_dataset_name(ds, name); 2286 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val); 2287 if (err == 0) 2288 err = EEXIST; 2289 if (err != ENOENT) 2290 break; 2291 err = 0; 2292 2293 /* The very first snapshot does not have a deadlist */ 2294 if (ds->ds_phys->ds_prev_snap_obj != 0) { 2295 if (err = bplist_space(&ds->ds_deadlist, 2296 &dlused, &dlcomp, &dluncomp)) 2297 break; 2298 pa->used += dlused; 2299 pa->comp += dlcomp; 2300 pa->uncomp += dluncomp; 2301 } 2302 } while (snap = list_next(&pa->snap_list, snap)); 2303 2304 /* 2305 * If we are a clone of a clone then we never reached ORIGIN, 2306 * so we need to subtract out the clone origin's used space. 2307 */ 2308 if (pa->clone_origin) { 2309 pa->used -= pa->clone_origin->ds_phys->ds_used_bytes; 2310 pa->comp -= pa->clone_origin->ds_phys->ds_compressed_bytes; 2311 pa->uncomp -= pa->clone_origin->ds_phys->ds_uncompressed_bytes; 2312 } 2313 2314 kmem_free(name, MAXPATHLEN); 2315 2316 /* Check that there is enough space here */ 2317 if (err == 0) { 2318 dsl_dir_t *odd = origin_ds->ds_dir; 2319 err = dsl_dir_transfer_possible(odd, hds->ds_dir, pa->used); 2320 } 2321 2322 return (err); 2323 } 2324 2325 static void 2326 dsl_dataset_promote_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2327 { 2328 dsl_dataset_t *hds = arg1; 2329 struct promotearg *pa = arg2; 2330 struct promotedsarg *snap = list_head(&pa->snap_list); 2331 dsl_dataset_t *origin_ds = snap->ds; 2332 dsl_dir_t *dd = hds->ds_dir; 2333 dsl_pool_t *dp = hds->ds_dir->dd_pool; 2334 dsl_dir_t *odd = NULL; 2335 char *name; 2336 2337 ASSERT(0 == (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE)); 2338 2339 /* 2340 * We need to explicitly open odd, since origin_ds's dd will be 2341 * changing. 2342 */ 2343 VERIFY(0 == dsl_dir_open_obj(dp, origin_ds->ds_dir->dd_object, 2344 NULL, FTAG, &odd)); 2345 2346 /* change origin's next snap */ 2347 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx); 2348 origin_ds->ds_phys->ds_next_snap_obj = pa->newnext_obj; 2349 2350 /* change origin */ 2351 dmu_buf_will_dirty(dd->dd_dbuf, tx); 2352 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object); 2353 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj; 2354 dmu_buf_will_dirty(odd->dd_dbuf, tx); 2355 odd->dd_phys->dd_origin_obj = origin_ds->ds_object; 2356 2357 /* move snapshots to this dir */ 2358 name = kmem_alloc(MAXPATHLEN, KM_SLEEP); 2359 do { 2360 dsl_dataset_t *ds = snap->ds; 2361 2362 /* move snap name entry */ 2363 dsl_dataset_name(ds, name); 2364 VERIFY(0 == dsl_dataset_snap_remove(pa->old_head, 2365 ds->ds_snapname, tx)); 2366 VERIFY(0 == zap_add(dp->dp_meta_objset, 2367 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname, 2368 8, 1, &ds->ds_object, tx)); 2369 2370 /* change containing dsl_dir */ 2371 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2372 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object); 2373 ds->ds_phys->ds_dir_obj = dd->dd_object; 2374 ASSERT3P(ds->ds_dir, ==, odd); 2375 dsl_dir_close(ds->ds_dir, ds); 2376 VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object, 2377 NULL, ds, &ds->ds_dir)); 2378 2379 ASSERT3U(dsl_prop_numcb(ds), ==, 0); 2380 } while (snap = list_next(&pa->snap_list, snap)); 2381 2382 /* change space accounting */ 2383 dsl_dir_diduse_space(odd, -pa->used, -pa->comp, -pa->uncomp, tx); 2384 dsl_dir_diduse_space(dd, pa->used, pa->comp, pa->uncomp, tx); 2385 origin_ds->ds_phys->ds_unique_bytes = pa->unique; 2386 2387 /* log history record */ 2388 spa_history_internal_log(LOG_DS_PROMOTE, dd->dd_pool->dp_spa, tx, 2389 cr, "dataset = %llu", hds->ds_object); 2390 2391 dsl_dir_close(odd, FTAG); 2392 kmem_free(name, MAXPATHLEN); 2393 } 2394 2395 int 2396 dsl_dataset_promote(const char *name) 2397 { 2398 dsl_dataset_t *ds; 2399 dsl_dir_t *dd; 2400 dsl_pool_t *dp; 2401 dmu_object_info_t doi; 2402 struct promotearg pa; 2403 struct promotedsarg *snap; 2404 uint64_t snap_obj; 2405 uint64_t last_snap = 0; 2406 int err; 2407 2408 err = dsl_dataset_hold(name, FTAG, &ds); 2409 if (err) 2410 return (err); 2411 dd = ds->ds_dir; 2412 dp = dd->dd_pool; 2413 2414 err = dmu_object_info(dp->dp_meta_objset, 2415 ds->ds_phys->ds_snapnames_zapobj, &doi); 2416 if (err) { 2417 dsl_dataset_rele(ds, FTAG); 2418 return (err); 2419 } 2420 2421 /* 2422 * We are going to inherit all the snapshots taken before our 2423 * origin (i.e., our new origin will be our parent's origin). 2424 * Take ownership of them so that we can rename them into our 2425 * namespace. 2426 */ 2427 pa.clone_origin = NULL; 2428 list_create(&pa.snap_list, 2429 sizeof (struct promotedsarg), offsetof(struct promotedsarg, link)); 2430 rw_enter(&dp->dp_config_rwlock, RW_READER); 2431 ASSERT(dd->dd_phys->dd_origin_obj != 0); 2432 snap_obj = dd->dd_phys->dd_origin_obj; 2433 while (snap_obj) { 2434 snap = kmem_alloc(sizeof (struct promotedsarg), KM_SLEEP); 2435 err = dsl_dataset_own_obj(dp, snap_obj, 0, FTAG, &snap->ds); 2436 if (err == ENOENT) { 2437 /* lost race with snapshot destroy */ 2438 struct promotedsarg *last = list_tail(&pa.snap_list); 2439 ASSERT(snap_obj != last->ds->ds_phys->ds_prev_snap_obj); 2440 snap_obj = last->ds->ds_phys->ds_prev_snap_obj; 2441 kmem_free(snap, sizeof (struct promotedsarg)); 2442 continue; 2443 } else if (err) { 2444 kmem_free(snap, sizeof (struct promotedsarg)); 2445 rw_exit(&dp->dp_config_rwlock); 2446 goto out; 2447 } 2448 /* 2449 * We could be a clone of a clone. If we reach our 2450 * parent's branch point, we're done. 2451 */ 2452 if (last_snap && 2453 snap->ds->ds_phys->ds_next_snap_obj != last_snap) { 2454 pa.clone_origin = snap->ds; 2455 kmem_free(snap, sizeof (struct promotedsarg)); 2456 snap_obj = 0; 2457 } else { 2458 list_insert_tail(&pa.snap_list, snap); 2459 last_snap = snap_obj; 2460 snap_obj = snap->ds->ds_phys->ds_prev_snap_obj; 2461 } 2462 } 2463 snap = list_head(&pa.snap_list); 2464 ASSERT(snap != NULL); 2465 err = dsl_dataset_hold_obj(dp, 2466 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &pa.old_head); 2467 rw_exit(&dp->dp_config_rwlock); 2468 2469 if (err) 2470 goto out; 2471 2472 /* 2473 * Add in 128x the snapnames zapobj size, since we will be moving 2474 * a bunch of snapnames to the promoted ds, and dirtying their 2475 * bonus buffers. 2476 */ 2477 err = dsl_sync_task_do(dp, dsl_dataset_promote_check, 2478 dsl_dataset_promote_sync, ds, &pa, 2 + 2 * doi.doi_physical_blks); 2479 2480 dsl_dataset_rele(pa.old_head, FTAG); 2481 out: 2482 while ((snap = list_tail(&pa.snap_list)) != NULL) { 2483 list_remove(&pa.snap_list, snap); 2484 dsl_dataset_disown(snap->ds, FTAG); 2485 kmem_free(snap, sizeof (struct promotedsarg)); 2486 } 2487 list_destroy(&pa.snap_list); 2488 if (pa.clone_origin) 2489 dsl_dataset_disown(pa.clone_origin, FTAG); 2490 dsl_dataset_rele(ds, FTAG); 2491 return (err); 2492 } 2493 2494 struct cloneswaparg { 2495 dsl_dataset_t *cds; /* clone dataset */ 2496 dsl_dataset_t *ohds; /* origin's head dataset */ 2497 boolean_t force; 2498 int64_t unused_refres_delta; /* change in unconsumed refreservation */ 2499 }; 2500 2501 /* ARGSUSED */ 2502 static int 2503 dsl_dataset_clone_swap_check(void *arg1, void *arg2, dmu_tx_t *tx) 2504 { 2505 struct cloneswaparg *csa = arg1; 2506 2507 /* they should both be heads */ 2508 if (dsl_dataset_is_snapshot(csa->cds) || 2509 dsl_dataset_is_snapshot(csa->ohds)) 2510 return (EINVAL); 2511 2512 /* the branch point should be just before them */ 2513 if (csa->cds->ds_prev != csa->ohds->ds_prev) 2514 return (EINVAL); 2515 2516 /* cds should be the clone */ 2517 if (csa->cds->ds_prev->ds_phys->ds_next_snap_obj != 2518 csa->ohds->ds_object) 2519 return (EINVAL); 2520 2521 /* the clone should be a child of the origin */ 2522 if (csa->cds->ds_dir->dd_parent != csa->ohds->ds_dir) 2523 return (EINVAL); 2524 2525 /* ohds shouldn't be modified unless 'force' */ 2526 if (!csa->force && dsl_dataset_modified_since_lastsnap(csa->ohds)) 2527 return (ETXTBSY); 2528 2529 /* adjust amount of any unconsumed refreservation */ 2530 csa->unused_refres_delta = 2531 (int64_t)MIN(csa->ohds->ds_reserved, 2532 csa->ohds->ds_phys->ds_unique_bytes) - 2533 (int64_t)MIN(csa->ohds->ds_reserved, 2534 csa->cds->ds_phys->ds_unique_bytes); 2535 2536 if (csa->unused_refres_delta > 0 && 2537 csa->unused_refres_delta > 2538 dsl_dir_space_available(csa->ohds->ds_dir, NULL, 0, TRUE)) 2539 return (ENOSPC); 2540 2541 return (0); 2542 } 2543 2544 /* ARGSUSED */ 2545 static void 2546 dsl_dataset_clone_swap_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2547 { 2548 struct cloneswaparg *csa = arg1; 2549 dsl_pool_t *dp = csa->cds->ds_dir->dd_pool; 2550 uint64_t itor = 0; 2551 blkptr_t bp; 2552 uint64_t unique = 0; 2553 int err; 2554 2555 ASSERT(csa->cds->ds_reserved == 0); 2556 ASSERT(csa->cds->ds_quota == csa->ohds->ds_quota); 2557 2558 dmu_buf_will_dirty(csa->cds->ds_dbuf, tx); 2559 dmu_buf_will_dirty(csa->ohds->ds_dbuf, tx); 2560 dmu_buf_will_dirty(csa->cds->ds_prev->ds_dbuf, tx); 2561 2562 if (csa->cds->ds_user_ptr != NULL) { 2563 csa->cds->ds_user_evict_func(csa->cds, csa->cds->ds_user_ptr); 2564 csa->cds->ds_user_ptr = NULL; 2565 } 2566 2567 if (csa->ohds->ds_user_ptr != NULL) { 2568 csa->ohds->ds_user_evict_func(csa->ohds, 2569 csa->ohds->ds_user_ptr); 2570 csa->ohds->ds_user_ptr = NULL; 2571 } 2572 2573 /* compute unique space */ 2574 while ((err = bplist_iterate(&csa->cds->ds_deadlist, 2575 &itor, &bp)) == 0) { 2576 if (bp.blk_birth > csa->cds->ds_prev->ds_phys->ds_prev_snap_txg) 2577 unique += bp_get_dasize(dp->dp_spa, &bp); 2578 } 2579 VERIFY(err == ENOENT); 2580 2581 /* reset origin's unique bytes */ 2582 csa->cds->ds_prev->ds_phys->ds_unique_bytes = unique; 2583 2584 /* swap blkptrs */ 2585 { 2586 blkptr_t tmp; 2587 tmp = csa->ohds->ds_phys->ds_bp; 2588 csa->ohds->ds_phys->ds_bp = csa->cds->ds_phys->ds_bp; 2589 csa->cds->ds_phys->ds_bp = tmp; 2590 } 2591 2592 /* set dd_*_bytes */ 2593 { 2594 int64_t dused, dcomp, duncomp; 2595 uint64_t cdl_used, cdl_comp, cdl_uncomp; 2596 uint64_t odl_used, odl_comp, odl_uncomp; 2597 2598 VERIFY(0 == bplist_space(&csa->cds->ds_deadlist, &cdl_used, 2599 &cdl_comp, &cdl_uncomp)); 2600 VERIFY(0 == bplist_space(&csa->ohds->ds_deadlist, &odl_used, 2601 &odl_comp, &odl_uncomp)); 2602 dused = csa->cds->ds_phys->ds_used_bytes + cdl_used - 2603 (csa->ohds->ds_phys->ds_used_bytes + odl_used); 2604 dcomp = csa->cds->ds_phys->ds_compressed_bytes + cdl_comp - 2605 (csa->ohds->ds_phys->ds_compressed_bytes + odl_comp); 2606 duncomp = csa->cds->ds_phys->ds_uncompressed_bytes + 2607 cdl_uncomp - 2608 (csa->ohds->ds_phys->ds_uncompressed_bytes + odl_uncomp); 2609 2610 dsl_dir_diduse_space(csa->ohds->ds_dir, 2611 dused, dcomp, duncomp, tx); 2612 dsl_dir_diduse_space(csa->cds->ds_dir, 2613 -dused, -dcomp, -duncomp, tx); 2614 } 2615 2616 #define SWITCH64(x, y) \ 2617 { \ 2618 uint64_t __tmp = (x); \ 2619 (x) = (y); \ 2620 (y) = __tmp; \ 2621 } 2622 2623 /* swap ds_*_bytes */ 2624 SWITCH64(csa->ohds->ds_phys->ds_used_bytes, 2625 csa->cds->ds_phys->ds_used_bytes); 2626 SWITCH64(csa->ohds->ds_phys->ds_compressed_bytes, 2627 csa->cds->ds_phys->ds_compressed_bytes); 2628 SWITCH64(csa->ohds->ds_phys->ds_uncompressed_bytes, 2629 csa->cds->ds_phys->ds_uncompressed_bytes); 2630 SWITCH64(csa->ohds->ds_phys->ds_unique_bytes, 2631 csa->cds->ds_phys->ds_unique_bytes); 2632 2633 /* apply any parent delta for change in unconsumed refreservation */ 2634 dsl_dir_diduse_space(csa->ohds->ds_dir, csa->unused_refres_delta, 2635 0, 0, tx); 2636 2637 /* swap deadlists */ 2638 bplist_close(&csa->cds->ds_deadlist); 2639 bplist_close(&csa->ohds->ds_deadlist); 2640 SWITCH64(csa->ohds->ds_phys->ds_deadlist_obj, 2641 csa->cds->ds_phys->ds_deadlist_obj); 2642 VERIFY(0 == bplist_open(&csa->cds->ds_deadlist, dp->dp_meta_objset, 2643 csa->cds->ds_phys->ds_deadlist_obj)); 2644 VERIFY(0 == bplist_open(&csa->ohds->ds_deadlist, dp->dp_meta_objset, 2645 csa->ohds->ds_phys->ds_deadlist_obj)); 2646 } 2647 2648 /* 2649 * Swap 'clone' with its origin head file system. Used at the end 2650 * of "online recv" to swizzle the file system to the new version. 2651 */ 2652 int 2653 dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head, 2654 boolean_t force) 2655 { 2656 struct cloneswaparg csa; 2657 int error; 2658 2659 ASSERT(clone->ds_owner); 2660 ASSERT(origin_head->ds_owner); 2661 retry: 2662 /* Need exclusive access for the swap */ 2663 rw_enter(&clone->ds_rwlock, RW_WRITER); 2664 if (!rw_tryenter(&origin_head->ds_rwlock, RW_WRITER)) { 2665 rw_exit(&clone->ds_rwlock); 2666 rw_enter(&origin_head->ds_rwlock, RW_WRITER); 2667 if (!rw_tryenter(&clone->ds_rwlock, RW_WRITER)) { 2668 rw_exit(&origin_head->ds_rwlock); 2669 goto retry; 2670 } 2671 } 2672 csa.cds = clone; 2673 csa.ohds = origin_head; 2674 csa.force = force; 2675 error = dsl_sync_task_do(clone->ds_dir->dd_pool, 2676 dsl_dataset_clone_swap_check, 2677 dsl_dataset_clone_swap_sync, &csa, NULL, 9); 2678 return (error); 2679 } 2680 2681 /* 2682 * Given a pool name and a dataset object number in that pool, 2683 * return the name of that dataset. 2684 */ 2685 int 2686 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf) 2687 { 2688 spa_t *spa; 2689 dsl_pool_t *dp; 2690 dsl_dataset_t *ds; 2691 int error; 2692 2693 if ((error = spa_open(pname, &spa, FTAG)) != 0) 2694 return (error); 2695 dp = spa_get_dsl(spa); 2696 rw_enter(&dp->dp_config_rwlock, RW_READER); 2697 if ((error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds)) == 0) { 2698 dsl_dataset_name(ds, buf); 2699 dsl_dataset_rele(ds, FTAG); 2700 } 2701 rw_exit(&dp->dp_config_rwlock); 2702 spa_close(spa, FTAG); 2703 2704 return (error); 2705 } 2706 2707 int 2708 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota, 2709 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv) 2710 { 2711 int error = 0; 2712 2713 ASSERT3S(asize, >, 0); 2714 2715 /* 2716 * *ref_rsrv is the portion of asize that will come from any 2717 * unconsumed refreservation space. 2718 */ 2719 *ref_rsrv = 0; 2720 2721 mutex_enter(&ds->ds_lock); 2722 /* 2723 * Make a space adjustment for reserved bytes. 2724 */ 2725 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) { 2726 ASSERT3U(*used, >=, 2727 ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2728 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes); 2729 *ref_rsrv = 2730 asize - MIN(asize, parent_delta(ds, asize + inflight)); 2731 } 2732 2733 if (!check_quota || ds->ds_quota == 0) { 2734 mutex_exit(&ds->ds_lock); 2735 return (0); 2736 } 2737 /* 2738 * If they are requesting more space, and our current estimate 2739 * is over quota, they get to try again unless the actual 2740 * on-disk is over quota and there are no pending changes (which 2741 * may free up space for us). 2742 */ 2743 if (ds->ds_phys->ds_used_bytes + inflight >= ds->ds_quota) { 2744 if (inflight > 0 || ds->ds_phys->ds_used_bytes < ds->ds_quota) 2745 error = ERESTART; 2746 else 2747 error = EDQUOT; 2748 } 2749 mutex_exit(&ds->ds_lock); 2750 2751 return (error); 2752 } 2753 2754 /* ARGSUSED */ 2755 static int 2756 dsl_dataset_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx) 2757 { 2758 dsl_dataset_t *ds = arg1; 2759 uint64_t *quotap = arg2; 2760 uint64_t new_quota = *quotap; 2761 2762 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_REFQUOTA) 2763 return (ENOTSUP); 2764 2765 if (new_quota == 0) 2766 return (0); 2767 2768 if (new_quota < ds->ds_phys->ds_used_bytes || 2769 new_quota < ds->ds_reserved) 2770 return (ENOSPC); 2771 2772 return (0); 2773 } 2774 2775 /* ARGSUSED */ 2776 void 2777 dsl_dataset_set_quota_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 2778 { 2779 dsl_dataset_t *ds = arg1; 2780 uint64_t *quotap = arg2; 2781 uint64_t new_quota = *quotap; 2782 2783 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2784 2785 ds->ds_quota = new_quota; 2786 2787 dsl_prop_set_uint64_sync(ds->ds_dir, "refquota", new_quota, cr, tx); 2788 2789 spa_history_internal_log(LOG_DS_REFQUOTA, ds->ds_dir->dd_pool->dp_spa, 2790 tx, cr, "%lld dataset = %llu ", 2791 (longlong_t)new_quota, ds->ds_object); 2792 } 2793 2794 int 2795 dsl_dataset_set_quota(const char *dsname, uint64_t quota) 2796 { 2797 dsl_dataset_t *ds; 2798 int err; 2799 2800 err = dsl_dataset_hold(dsname, FTAG, &ds); 2801 if (err) 2802 return (err); 2803 2804 if (quota != ds->ds_quota) { 2805 /* 2806 * If someone removes a file, then tries to set the quota, we 2807 * want to make sure the file freeing takes effect. 2808 */ 2809 txg_wait_open(ds->ds_dir->dd_pool, 0); 2810 2811 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2812 dsl_dataset_set_quota_check, dsl_dataset_set_quota_sync, 2813 ds, "a, 0); 2814 } 2815 dsl_dataset_rele(ds, FTAG); 2816 return (err); 2817 } 2818 2819 static int 2820 dsl_dataset_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx) 2821 { 2822 dsl_dataset_t *ds = arg1; 2823 uint64_t *reservationp = arg2; 2824 uint64_t new_reservation = *reservationp; 2825 int64_t delta; 2826 uint64_t unique; 2827 2828 if (new_reservation > INT64_MAX) 2829 return (EOVERFLOW); 2830 2831 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < 2832 SPA_VERSION_REFRESERVATION) 2833 return (ENOTSUP); 2834 2835 if (dsl_dataset_is_snapshot(ds)) 2836 return (EINVAL); 2837 2838 /* 2839 * If we are doing the preliminary check in open context, the 2840 * space estimates may be inaccurate. 2841 */ 2842 if (!dmu_tx_is_syncing(tx)) 2843 return (0); 2844 2845 mutex_enter(&ds->ds_lock); 2846 unique = dsl_dataset_unique(ds); 2847 delta = MAX(unique, new_reservation) - MAX(unique, ds->ds_reserved); 2848 mutex_exit(&ds->ds_lock); 2849 2850 if (delta > 0 && 2851 delta > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) 2852 return (ENOSPC); 2853 if (delta > 0 && ds->ds_quota > 0 && 2854 new_reservation > ds->ds_quota) 2855 return (ENOSPC); 2856 2857 return (0); 2858 } 2859 2860 /* ARGSUSED */ 2861 static void 2862 dsl_dataset_set_reservation_sync(void *arg1, void *arg2, cred_t *cr, 2863 dmu_tx_t *tx) 2864 { 2865 dsl_dataset_t *ds = arg1; 2866 uint64_t *reservationp = arg2; 2867 uint64_t new_reservation = *reservationp; 2868 uint64_t unique; 2869 int64_t delta; 2870 2871 dmu_buf_will_dirty(ds->ds_dbuf, tx); 2872 2873 mutex_enter(&ds->ds_lock); 2874 unique = dsl_dataset_unique(ds); 2875 delta = MAX(0, (int64_t)(new_reservation - unique)) - 2876 MAX(0, (int64_t)(ds->ds_reserved - unique)); 2877 ds->ds_reserved = new_reservation; 2878 mutex_exit(&ds->ds_lock); 2879 2880 dsl_prop_set_uint64_sync(ds->ds_dir, "refreservation", 2881 new_reservation, cr, tx); 2882 2883 dsl_dir_diduse_space(ds->ds_dir, delta, 0, 0, tx); 2884 2885 spa_history_internal_log(LOG_DS_REFRESERV, 2886 ds->ds_dir->dd_pool->dp_spa, tx, cr, "%lld dataset = %llu", 2887 (longlong_t)new_reservation, 2888 ds->ds_dir->dd_phys->dd_head_dataset_obj); 2889 } 2890 2891 int 2892 dsl_dataset_set_reservation(const char *dsname, uint64_t reservation) 2893 { 2894 dsl_dataset_t *ds; 2895 int err; 2896 2897 err = dsl_dataset_hold(dsname, FTAG, &ds); 2898 if (err) 2899 return (err); 2900 2901 err = dsl_sync_task_do(ds->ds_dir->dd_pool, 2902 dsl_dataset_set_reservation_check, 2903 dsl_dataset_set_reservation_sync, ds, &reservation, 0); 2904 dsl_dataset_rele(ds, FTAG); 2905 return (err); 2906 } 2907