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/dsl_pool.h> 27 #include <sys/dsl_dataset.h> 28 #include <sys/dsl_dir.h> 29 #include <sys/dsl_synctask.h> 30 #include <sys/dmu_tx.h> 31 #include <sys/dmu_objset.h> 32 #include <sys/arc.h> 33 #include <sys/zap.h> 34 #include <sys/zio.h> 35 #include <sys/zfs_context.h> 36 #include <sys/fs/zfs.h> 37 #include <sys/zfs_znode.h> 38 #include <sys/spa_impl.h> 39 40 int zfs_no_write_throttle = 0; 41 int zfs_write_limit_shift = 3; /* 1/8th of physical memory */ 42 int zfs_txg_synctime = 5; /* target secs to sync a txg */ 43 44 uint64_t zfs_write_limit_min = 32 << 20; /* min write limit is 32MB */ 45 uint64_t zfs_write_limit_max = 0; /* max data payload per txg */ 46 uint64_t zfs_write_limit_inflated = 0; 47 uint64_t zfs_write_limit_override = 0; 48 49 kmutex_t zfs_write_limit_lock; 50 51 static pgcnt_t old_physmem = 0; 52 53 static int 54 dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **ddp) 55 { 56 uint64_t obj; 57 int err; 58 59 err = zap_lookup(dp->dp_meta_objset, 60 dp->dp_root_dir->dd_phys->dd_child_dir_zapobj, 61 name, sizeof (obj), 1, &obj); 62 if (err) 63 return (err); 64 65 return (dsl_dir_open_obj(dp, obj, name, dp, ddp)); 66 } 67 68 static dsl_pool_t * 69 dsl_pool_open_impl(spa_t *spa, uint64_t txg) 70 { 71 dsl_pool_t *dp; 72 blkptr_t *bp = spa_get_rootblkptr(spa); 73 74 dp = kmem_zalloc(sizeof (dsl_pool_t), KM_SLEEP); 75 dp->dp_spa = spa; 76 dp->dp_meta_rootbp = *bp; 77 rw_init(&dp->dp_config_rwlock, NULL, RW_DEFAULT, NULL); 78 dp->dp_write_limit = zfs_write_limit_min; 79 txg_init(dp, txg); 80 81 txg_list_create(&dp->dp_dirty_datasets, 82 offsetof(dsl_dataset_t, ds_dirty_link)); 83 txg_list_create(&dp->dp_dirty_dirs, 84 offsetof(dsl_dir_t, dd_dirty_link)); 85 txg_list_create(&dp->dp_sync_tasks, 86 offsetof(dsl_sync_task_group_t, dstg_node)); 87 list_create(&dp->dp_synced_datasets, sizeof (dsl_dataset_t), 88 offsetof(dsl_dataset_t, ds_synced_link)); 89 90 mutex_init(&dp->dp_lock, NULL, MUTEX_DEFAULT, NULL); 91 mutex_init(&dp->dp_scrub_cancel_lock, NULL, MUTEX_DEFAULT, NULL); 92 93 return (dp); 94 } 95 96 int 97 dsl_pool_open(spa_t *spa, uint64_t txg, dsl_pool_t **dpp) 98 { 99 int err; 100 dsl_pool_t *dp = dsl_pool_open_impl(spa, txg); 101 dsl_dir_t *dd; 102 dsl_dataset_t *ds; 103 objset_impl_t *osi; 104 105 rw_enter(&dp->dp_config_rwlock, RW_WRITER); 106 err = dmu_objset_open_impl(spa, NULL, &dp->dp_meta_rootbp, &osi); 107 if (err) 108 goto out; 109 dp->dp_meta_objset = &osi->os; 110 111 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 112 DMU_POOL_ROOT_DATASET, sizeof (uint64_t), 1, 113 &dp->dp_root_dir_obj); 114 if (err) 115 goto out; 116 117 err = dsl_dir_open_obj(dp, dp->dp_root_dir_obj, 118 NULL, dp, &dp->dp_root_dir); 119 if (err) 120 goto out; 121 122 err = dsl_pool_open_special_dir(dp, MOS_DIR_NAME, &dp->dp_mos_dir); 123 if (err) 124 goto out; 125 126 if (spa_version(spa) >= SPA_VERSION_ORIGIN) { 127 err = dsl_pool_open_special_dir(dp, ORIGIN_DIR_NAME, &dd); 128 if (err) 129 goto out; 130 err = dsl_dataset_hold_obj(dp, dd->dd_phys->dd_head_dataset_obj, 131 FTAG, &ds); 132 if (err) 133 goto out; 134 err = dsl_dataset_hold_obj(dp, ds->ds_phys->ds_prev_snap_obj, 135 dp, &dp->dp_origin_snap); 136 if (err) 137 goto out; 138 dsl_dataset_rele(ds, FTAG); 139 dsl_dir_close(dd, dp); 140 } 141 142 /* get scrub status */ 143 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 144 DMU_POOL_SCRUB_FUNC, sizeof (uint32_t), 1, 145 &dp->dp_scrub_func); 146 if (err == 0) { 147 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 148 DMU_POOL_SCRUB_QUEUE, sizeof (uint64_t), 1, 149 &dp->dp_scrub_queue_obj); 150 if (err) 151 goto out; 152 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 153 DMU_POOL_SCRUB_MIN_TXG, sizeof (uint64_t), 1, 154 &dp->dp_scrub_min_txg); 155 if (err) 156 goto out; 157 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 158 DMU_POOL_SCRUB_MAX_TXG, sizeof (uint64_t), 1, 159 &dp->dp_scrub_max_txg); 160 if (err) 161 goto out; 162 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 163 DMU_POOL_SCRUB_BOOKMARK, sizeof (uint64_t), 4, 164 &dp->dp_scrub_bookmark); 165 if (err) 166 goto out; 167 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 168 DMU_POOL_SCRUB_ERRORS, sizeof (uint64_t), 1, 169 &spa->spa_scrub_errors); 170 if (err) 171 goto out; 172 if (spa_version(spa) < SPA_VERSION_DSL_SCRUB) { 173 /* 174 * A new-type scrub was in progress on an old 175 * pool. Restart from the beginning, since the 176 * old software may have changed the pool in the 177 * meantime. 178 */ 179 dsl_pool_scrub_restart(dp); 180 } 181 } else { 182 /* 183 * It's OK if there is no scrub in progress (and if 184 * there was an I/O error, ignore it). 185 */ 186 err = 0; 187 } 188 189 out: 190 rw_exit(&dp->dp_config_rwlock); 191 if (err) 192 dsl_pool_close(dp); 193 else 194 *dpp = dp; 195 196 return (err); 197 } 198 199 void 200 dsl_pool_close(dsl_pool_t *dp) 201 { 202 /* drop our references from dsl_pool_open() */ 203 204 /* 205 * Since we held the origin_snap from "syncing" context (which 206 * includes pool-opening context), it actually only got a "ref" 207 * and not a hold, so just drop that here. 208 */ 209 if (dp->dp_origin_snap) 210 dsl_dataset_drop_ref(dp->dp_origin_snap, dp); 211 if (dp->dp_mos_dir) 212 dsl_dir_close(dp->dp_mos_dir, dp); 213 if (dp->dp_root_dir) 214 dsl_dir_close(dp->dp_root_dir, dp); 215 216 /* undo the dmu_objset_open_impl(mos) from dsl_pool_open() */ 217 if (dp->dp_meta_objset) 218 dmu_objset_evict(NULL, dp->dp_meta_objset->os); 219 220 txg_list_destroy(&dp->dp_dirty_datasets); 221 txg_list_destroy(&dp->dp_dirty_dirs); 222 list_destroy(&dp->dp_synced_datasets); 223 224 arc_flush(dp->dp_spa); 225 txg_fini(dp); 226 rw_destroy(&dp->dp_config_rwlock); 227 mutex_destroy(&dp->dp_lock); 228 mutex_destroy(&dp->dp_scrub_cancel_lock); 229 if (dp->dp_blkstats) 230 kmem_free(dp->dp_blkstats, sizeof (zfs_all_blkstats_t)); 231 kmem_free(dp, sizeof (dsl_pool_t)); 232 } 233 234 dsl_pool_t * 235 dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg) 236 { 237 int err; 238 dsl_pool_t *dp = dsl_pool_open_impl(spa, txg); 239 dmu_tx_t *tx = dmu_tx_create_assigned(dp, txg); 240 objset_impl_t *osip; 241 dsl_dataset_t *ds; 242 uint64_t dsobj; 243 244 /* create and open the MOS (meta-objset) */ 245 dp->dp_meta_objset = &dmu_objset_create_impl(spa, 246 NULL, &dp->dp_meta_rootbp, DMU_OST_META, tx)->os; 247 248 /* create the pool directory */ 249 err = zap_create_claim(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, 250 DMU_OT_OBJECT_DIRECTORY, DMU_OT_NONE, 0, tx); 251 ASSERT3U(err, ==, 0); 252 253 /* create and open the root dir */ 254 dp->dp_root_dir_obj = dsl_dir_create_sync(dp, NULL, NULL, tx); 255 VERIFY(0 == dsl_dir_open_obj(dp, dp->dp_root_dir_obj, 256 NULL, dp, &dp->dp_root_dir)); 257 258 /* create and open the meta-objset dir */ 259 (void) dsl_dir_create_sync(dp, dp->dp_root_dir, MOS_DIR_NAME, tx); 260 VERIFY(0 == dsl_pool_open_special_dir(dp, 261 MOS_DIR_NAME, &dp->dp_mos_dir)); 262 263 if (spa_version(spa) >= SPA_VERSION_DSL_SCRUB) 264 dsl_pool_create_origin(dp, tx); 265 266 /* create the root dataset */ 267 dsobj = dsl_dataset_create_sync_dd(dp->dp_root_dir, NULL, 0, tx); 268 269 /* create the root objset */ 270 VERIFY(0 == dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 271 osip = dmu_objset_create_impl(dp->dp_spa, ds, 272 dsl_dataset_get_blkptr(ds), DMU_OST_ZFS, tx); 273 #ifdef _KERNEL 274 zfs_create_fs(&osip->os, kcred, zplprops, tx); 275 #endif 276 dsl_dataset_rele(ds, FTAG); 277 278 dmu_tx_commit(tx); 279 280 return (dp); 281 } 282 283 void 284 dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) 285 { 286 zio_t *zio; 287 dmu_tx_t *tx; 288 dsl_dir_t *dd; 289 dsl_dataset_t *ds; 290 dsl_sync_task_group_t *dstg; 291 objset_impl_t *mosi = dp->dp_meta_objset->os; 292 hrtime_t start, write_time; 293 uint64_t data_written; 294 int err; 295 296 tx = dmu_tx_create_assigned(dp, txg); 297 298 dp->dp_read_overhead = 0; 299 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 300 while (ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) { 301 if (!list_link_active(&ds->ds_synced_link)) 302 list_insert_tail(&dp->dp_synced_datasets, ds); 303 else 304 dmu_buf_rele(ds->ds_dbuf, ds); 305 dsl_dataset_sync(ds, zio, tx); 306 } 307 DTRACE_PROBE(pool_sync__1setup); 308 309 start = gethrtime(); 310 err = zio_wait(zio); 311 write_time = gethrtime() - start; 312 ASSERT(err == 0); 313 DTRACE_PROBE(pool_sync__2rootzio); 314 315 while (dstg = txg_list_remove(&dp->dp_sync_tasks, txg)) 316 dsl_sync_task_group_sync(dstg, tx); 317 DTRACE_PROBE(pool_sync__3task); 318 319 start = gethrtime(); 320 while (dd = txg_list_remove(&dp->dp_dirty_dirs, txg)) 321 dsl_dir_sync(dd, tx); 322 write_time += gethrtime() - start; 323 324 if (spa_sync_pass(dp->dp_spa) == 1) 325 dsl_pool_scrub_sync(dp, tx); 326 327 start = gethrtime(); 328 if (list_head(&mosi->os_dirty_dnodes[txg & TXG_MASK]) != NULL || 329 list_head(&mosi->os_free_dnodes[txg & TXG_MASK]) != NULL) { 330 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); 331 dmu_objset_sync(mosi, zio, tx); 332 err = zio_wait(zio); 333 ASSERT(err == 0); 334 dprintf_bp(&dp->dp_meta_rootbp, "meta objset rootbp is %s", ""); 335 spa_set_rootblkptr(dp->dp_spa, &dp->dp_meta_rootbp); 336 } 337 write_time += gethrtime() - start; 338 DTRACE_PROBE2(pool_sync__4io, hrtime_t, write_time, 339 hrtime_t, dp->dp_read_overhead); 340 write_time -= dp->dp_read_overhead; 341 342 dmu_tx_commit(tx); 343 344 data_written = dp->dp_space_towrite[txg & TXG_MASK]; 345 dp->dp_space_towrite[txg & TXG_MASK] = 0; 346 ASSERT(dp->dp_tempreserved[txg & TXG_MASK] == 0); 347 348 /* 349 * If the write limit max has not been explicitly set, set it 350 * to a fraction of available physical memory (default 1/8th). 351 * Note that we must inflate the limit because the spa 352 * inflates write sizes to account for data replication. 353 * Check this each sync phase to catch changing memory size. 354 */ 355 if (physmem != old_physmem && zfs_write_limit_shift) { 356 mutex_enter(&zfs_write_limit_lock); 357 old_physmem = physmem; 358 zfs_write_limit_max = ptob(physmem) >> zfs_write_limit_shift; 359 zfs_write_limit_inflated = MAX(zfs_write_limit_min, 360 spa_get_asize(dp->dp_spa, zfs_write_limit_max)); 361 mutex_exit(&zfs_write_limit_lock); 362 } 363 364 /* 365 * Attempt to keep the sync time consistent by adjusting the 366 * amount of write traffic allowed into each transaction group. 367 * Weight the throughput calculation towards the current value: 368 * thru = 3/4 old_thru + 1/4 new_thru 369 */ 370 ASSERT(zfs_write_limit_min > 0); 371 if (data_written > zfs_write_limit_min / 8 && write_time > 0) { 372 uint64_t throughput = (data_written * NANOSEC) / write_time; 373 if (dp->dp_throughput) 374 dp->dp_throughput = throughput / 4 + 375 3 * dp->dp_throughput / 4; 376 else 377 dp->dp_throughput = throughput; 378 dp->dp_write_limit = MIN(zfs_write_limit_inflated, 379 MAX(zfs_write_limit_min, 380 dp->dp_throughput * zfs_txg_synctime)); 381 } 382 } 383 384 void 385 dsl_pool_zil_clean(dsl_pool_t *dp) 386 { 387 dsl_dataset_t *ds; 388 389 while (ds = list_head(&dp->dp_synced_datasets)) { 390 list_remove(&dp->dp_synced_datasets, ds); 391 ASSERT(ds->ds_user_ptr != NULL); 392 zil_clean(((objset_impl_t *)ds->ds_user_ptr)->os_zil); 393 dmu_buf_rele(ds->ds_dbuf, ds); 394 } 395 } 396 397 /* 398 * TRUE if the current thread is the tx_sync_thread or if we 399 * are being called from SPA context during pool initialization. 400 */ 401 int 402 dsl_pool_sync_context(dsl_pool_t *dp) 403 { 404 return (curthread == dp->dp_tx.tx_sync_thread || 405 spa_get_dsl(dp->dp_spa) == NULL); 406 } 407 408 uint64_t 409 dsl_pool_adjustedsize(dsl_pool_t *dp, boolean_t netfree) 410 { 411 uint64_t space, resv; 412 413 /* 414 * Reserve about 1.6% (1/64), or at least 32MB, for allocation 415 * efficiency. 416 * XXX The intent log is not accounted for, so it must fit 417 * within this slop. 418 * 419 * If we're trying to assess whether it's OK to do a free, 420 * cut the reservation in half to allow forward progress 421 * (e.g. make it possible to rm(1) files from a full pool). 422 */ 423 space = spa_get_dspace(dp->dp_spa); 424 resv = MAX(space >> 6, SPA_MINDEVSIZE >> 1); 425 if (netfree) 426 resv >>= 1; 427 428 return (space - resv); 429 } 430 431 int 432 dsl_pool_tempreserve_space(dsl_pool_t *dp, uint64_t space, dmu_tx_t *tx) 433 { 434 uint64_t reserved = 0; 435 uint64_t write_limit = (zfs_write_limit_override ? 436 zfs_write_limit_override : dp->dp_write_limit); 437 438 if (zfs_no_write_throttle) { 439 atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], 440 space); 441 return (0); 442 } 443 444 /* 445 * Check to see if we have exceeded the maximum allowed IO for 446 * this transaction group. We can do this without locks since 447 * a little slop here is ok. Note that we do the reserved check 448 * with only half the requested reserve: this is because the 449 * reserve requests are worst-case, and we really don't want to 450 * throttle based off of worst-case estimates. 451 */ 452 if (write_limit > 0) { 453 reserved = dp->dp_space_towrite[tx->tx_txg & TXG_MASK] 454 + dp->dp_tempreserved[tx->tx_txg & TXG_MASK] / 2; 455 456 if (reserved && reserved > write_limit) 457 return (ERESTART); 458 } 459 460 atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], space); 461 462 /* 463 * If this transaction group is over 7/8ths capacity, delay 464 * the caller 1 clock tick. This will slow down the "fill" 465 * rate until the sync process can catch up with us. 466 */ 467 if (reserved && reserved > (write_limit - (write_limit >> 3))) 468 txg_delay(dp, tx->tx_txg, 1); 469 470 return (0); 471 } 472 473 void 474 dsl_pool_tempreserve_clear(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx) 475 { 476 ASSERT(dp->dp_tempreserved[tx->tx_txg & TXG_MASK] >= space); 477 atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], -space); 478 } 479 480 void 481 dsl_pool_memory_pressure(dsl_pool_t *dp) 482 { 483 uint64_t space_inuse = 0; 484 int i; 485 486 if (dp->dp_write_limit == zfs_write_limit_min) 487 return; 488 489 for (i = 0; i < TXG_SIZE; i++) { 490 space_inuse += dp->dp_space_towrite[i]; 491 space_inuse += dp->dp_tempreserved[i]; 492 } 493 dp->dp_write_limit = MAX(zfs_write_limit_min, 494 MIN(dp->dp_write_limit, space_inuse / 4)); 495 } 496 497 void 498 dsl_pool_willuse_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx) 499 { 500 if (space > 0) { 501 mutex_enter(&dp->dp_lock); 502 dp->dp_space_towrite[tx->tx_txg & TXG_MASK] += space; 503 mutex_exit(&dp->dp_lock); 504 } 505 } 506 507 /* ARGSUSED */ 508 static int 509 upgrade_clones_cb(spa_t *spa, uint64_t dsobj, const char *dsname, void *arg) 510 { 511 dmu_tx_t *tx = arg; 512 dsl_dataset_t *ds, *prev = NULL; 513 int err; 514 dsl_pool_t *dp = spa_get_dsl(spa); 515 516 err = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds); 517 if (err) 518 return (err); 519 520 while (ds->ds_phys->ds_prev_snap_obj != 0) { 521 err = dsl_dataset_hold_obj(dp, ds->ds_phys->ds_prev_snap_obj, 522 FTAG, &prev); 523 if (err) { 524 dsl_dataset_rele(ds, FTAG); 525 return (err); 526 } 527 528 if (prev->ds_phys->ds_next_snap_obj != ds->ds_object) 529 break; 530 dsl_dataset_rele(ds, FTAG); 531 ds = prev; 532 prev = NULL; 533 } 534 535 if (prev == NULL) { 536 prev = dp->dp_origin_snap; 537 538 /* 539 * The $ORIGIN can't have any data, or the accounting 540 * will be wrong. 541 */ 542 ASSERT(prev->ds_phys->ds_bp.blk_birth == 0); 543 544 /* The origin doesn't get attached to itself */ 545 if (ds->ds_object == prev->ds_object) { 546 dsl_dataset_rele(ds, FTAG); 547 return (0); 548 } 549 550 dmu_buf_will_dirty(ds->ds_dbuf, tx); 551 ds->ds_phys->ds_prev_snap_obj = prev->ds_object; 552 ds->ds_phys->ds_prev_snap_txg = prev->ds_phys->ds_creation_txg; 553 554 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); 555 ds->ds_dir->dd_phys->dd_origin_obj = prev->ds_object; 556 557 dmu_buf_will_dirty(prev->ds_dbuf, tx); 558 prev->ds_phys->ds_num_children++; 559 560 if (ds->ds_phys->ds_next_snap_obj == 0) { 561 ASSERT(ds->ds_prev == NULL); 562 VERIFY(0 == dsl_dataset_hold_obj(dp, 563 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev)); 564 } 565 } 566 567 ASSERT(ds->ds_dir->dd_phys->dd_origin_obj == prev->ds_object); 568 ASSERT(ds->ds_phys->ds_prev_snap_obj == prev->ds_object); 569 570 if (prev->ds_phys->ds_next_clones_obj == 0) { 571 prev->ds_phys->ds_next_clones_obj = 572 zap_create(dp->dp_meta_objset, 573 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); 574 } 575 VERIFY(0 == zap_add_int(dp->dp_meta_objset, 576 prev->ds_phys->ds_next_clones_obj, ds->ds_object, tx)); 577 578 dsl_dataset_rele(ds, FTAG); 579 if (prev != dp->dp_origin_snap) 580 dsl_dataset_rele(prev, FTAG); 581 return (0); 582 } 583 584 void 585 dsl_pool_upgrade_clones(dsl_pool_t *dp, dmu_tx_t *tx) 586 { 587 ASSERT(dmu_tx_is_syncing(tx)); 588 ASSERT(dp->dp_origin_snap != NULL); 589 590 (void) dmu_objset_find_spa(dp->dp_spa, NULL, upgrade_clones_cb, 591 tx, DS_FIND_CHILDREN); 592 } 593 594 void 595 dsl_pool_create_origin(dsl_pool_t *dp, dmu_tx_t *tx) 596 { 597 uint64_t dsobj; 598 dsl_dataset_t *ds; 599 600 ASSERT(dmu_tx_is_syncing(tx)); 601 ASSERT(dp->dp_origin_snap == NULL); 602 603 /* create the origin dir, ds, & snap-ds */ 604 rw_enter(&dp->dp_config_rwlock, RW_WRITER); 605 dsobj = dsl_dataset_create_sync(dp->dp_root_dir, ORIGIN_DIR_NAME, 606 NULL, 0, kcred, tx); 607 VERIFY(0 == dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); 608 dsl_dataset_snapshot_sync(ds, ORIGIN_DIR_NAME, kcred, tx); 609 VERIFY(0 == dsl_dataset_hold_obj(dp, ds->ds_phys->ds_prev_snap_obj, 610 dp, &dp->dp_origin_snap)); 611 dsl_dataset_rele(ds, FTAG); 612 rw_exit(&dp->dp_config_rwlock); 613 } 614