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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2014 by Delphix. All rights reserved. 24 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 25 */ 26 27 #include <sys/zfs_context.h> 28 #include <sys/spa_impl.h> 29 #include <sys/spa_boot.h> 30 #include <sys/zio.h> 31 #include <sys/zio_checksum.h> 32 #include <sys/zio_compress.h> 33 #include <sys/dmu.h> 34 #include <sys/dmu_tx.h> 35 #include <sys/zap.h> 36 #include <sys/zil.h> 37 #include <sys/vdev_impl.h> 38 #include <sys/metaslab.h> 39 #include <sys/uberblock_impl.h> 40 #include <sys/txg.h> 41 #include <sys/avl.h> 42 #include <sys/unique.h> 43 #include <sys/dsl_pool.h> 44 #include <sys/dsl_dir.h> 45 #include <sys/dsl_prop.h> 46 #include <sys/dsl_scan.h> 47 #include <sys/fs/zfs.h> 48 #include <sys/metaslab_impl.h> 49 #include <sys/arc.h> 50 #include <sys/ddt.h> 51 #include "zfs_prop.h" 52 #include "zfeature_common.h" 53 54 /* 55 * SPA locking 56 * 57 * There are four basic locks for managing spa_t structures: 58 * 59 * spa_namespace_lock (global mutex) 60 * 61 * This lock must be acquired to do any of the following: 62 * 63 * - Lookup a spa_t by name 64 * - Add or remove a spa_t from the namespace 65 * - Increase spa_refcount from non-zero 66 * - Check if spa_refcount is zero 67 * - Rename a spa_t 68 * - add/remove/attach/detach devices 69 * - Held for the duration of create/destroy/import/export 70 * 71 * It does not need to handle recursion. A create or destroy may 72 * reference objects (files or zvols) in other pools, but by 73 * definition they must have an existing reference, and will never need 74 * to lookup a spa_t by name. 75 * 76 * spa_refcount (per-spa refcount_t protected by mutex) 77 * 78 * This reference count keep track of any active users of the spa_t. The 79 * spa_t cannot be destroyed or freed while this is non-zero. Internally, 80 * the refcount is never really 'zero' - opening a pool implicitly keeps 81 * some references in the DMU. Internally we check against spa_minref, but 82 * present the image of a zero/non-zero value to consumers. 83 * 84 * spa_config_lock[] (per-spa array of rwlocks) 85 * 86 * This protects the spa_t from config changes, and must be held in 87 * the following circumstances: 88 * 89 * - RW_READER to perform I/O to the spa 90 * - RW_WRITER to change the vdev config 91 * 92 * The locking order is fairly straightforward: 93 * 94 * spa_namespace_lock -> spa_refcount 95 * 96 * The namespace lock must be acquired to increase the refcount from 0 97 * or to check if it is zero. 98 * 99 * spa_refcount -> spa_config_lock[] 100 * 101 * There must be at least one valid reference on the spa_t to acquire 102 * the config lock. 103 * 104 * spa_namespace_lock -> spa_config_lock[] 105 * 106 * The namespace lock must always be taken before the config lock. 107 * 108 * 109 * The spa_namespace_lock can be acquired directly and is globally visible. 110 * 111 * The namespace is manipulated using the following functions, all of which 112 * require the spa_namespace_lock to be held. 113 * 114 * spa_lookup() Lookup a spa_t by name. 115 * 116 * spa_add() Create a new spa_t in the namespace. 117 * 118 * spa_remove() Remove a spa_t from the namespace. This also 119 * frees up any memory associated with the spa_t. 120 * 121 * spa_next() Returns the next spa_t in the system, or the 122 * first if NULL is passed. 123 * 124 * spa_evict_all() Shutdown and remove all spa_t structures in 125 * the system. 126 * 127 * spa_guid_exists() Determine whether a pool/device guid exists. 128 * 129 * The spa_refcount is manipulated using the following functions: 130 * 131 * spa_open_ref() Adds a reference to the given spa_t. Must be 132 * called with spa_namespace_lock held if the 133 * refcount is currently zero. 134 * 135 * spa_close() Remove a reference from the spa_t. This will 136 * not free the spa_t or remove it from the 137 * namespace. No locking is required. 138 * 139 * spa_refcount_zero() Returns true if the refcount is currently 140 * zero. Must be called with spa_namespace_lock 141 * held. 142 * 143 * The spa_config_lock[] is an array of rwlocks, ordered as follows: 144 * SCL_CONFIG > SCL_STATE > SCL_ALLOC > SCL_ZIO > SCL_FREE > SCL_VDEV. 145 * spa_config_lock[] is manipulated with spa_config_{enter,exit,held}(). 146 * 147 * To read the configuration, it suffices to hold one of these locks as reader. 148 * To modify the configuration, you must hold all locks as writer. To modify 149 * vdev state without altering the vdev tree's topology (e.g. online/offline), 150 * you must hold SCL_STATE and SCL_ZIO as writer. 151 * 152 * We use these distinct config locks to avoid recursive lock entry. 153 * For example, spa_sync() (which holds SCL_CONFIG as reader) induces 154 * block allocations (SCL_ALLOC), which may require reading space maps 155 * from disk (dmu_read() -> zio_read() -> SCL_ZIO). 156 * 157 * The spa config locks cannot be normal rwlocks because we need the 158 * ability to hand off ownership. For example, SCL_ZIO is acquired 159 * by the issuing thread and later released by an interrupt thread. 160 * They do, however, obey the usual write-wanted semantics to prevent 161 * writer (i.e. system administrator) starvation. 162 * 163 * The lock acquisition rules are as follows: 164 * 165 * SCL_CONFIG 166 * Protects changes to the vdev tree topology, such as vdev 167 * add/remove/attach/detach. Protects the dirty config list 168 * (spa_config_dirty_list) and the set of spares and l2arc devices. 169 * 170 * SCL_STATE 171 * Protects changes to pool state and vdev state, such as vdev 172 * online/offline/fault/degrade/clear. Protects the dirty state list 173 * (spa_state_dirty_list) and global pool state (spa_state). 174 * 175 * SCL_ALLOC 176 * Protects changes to metaslab groups and classes. 177 * Held as reader by metaslab_alloc() and metaslab_claim(). 178 * 179 * SCL_ZIO 180 * Held by bp-level zios (those which have no io_vd upon entry) 181 * to prevent changes to the vdev tree. The bp-level zio implicitly 182 * protects all of its vdev child zios, which do not hold SCL_ZIO. 183 * 184 * SCL_FREE 185 * Protects changes to metaslab groups and classes. 186 * Held as reader by metaslab_free(). SCL_FREE is distinct from 187 * SCL_ALLOC, and lower than SCL_ZIO, so that we can safely free 188 * blocks in zio_done() while another i/o that holds either 189 * SCL_ALLOC or SCL_ZIO is waiting for this i/o to complete. 190 * 191 * SCL_VDEV 192 * Held as reader to prevent changes to the vdev tree during trivial 193 * inquiries such as bp_get_dsize(). SCL_VDEV is distinct from the 194 * other locks, and lower than all of them, to ensure that it's safe 195 * to acquire regardless of caller context. 196 * 197 * In addition, the following rules apply: 198 * 199 * (a) spa_props_lock protects pool properties, spa_config and spa_config_list. 200 * The lock ordering is SCL_CONFIG > spa_props_lock. 201 * 202 * (b) I/O operations on leaf vdevs. For any zio operation that takes 203 * an explicit vdev_t argument -- such as zio_ioctl(), zio_read_phys(), 204 * or zio_write_phys() -- the caller must ensure that the config cannot 205 * cannot change in the interim, and that the vdev cannot be reopened. 206 * SCL_STATE as reader suffices for both. 207 * 208 * The vdev configuration is protected by spa_vdev_enter() / spa_vdev_exit(). 209 * 210 * spa_vdev_enter() Acquire the namespace lock and the config lock 211 * for writing. 212 * 213 * spa_vdev_exit() Release the config lock, wait for all I/O 214 * to complete, sync the updated configs to the 215 * cache, and release the namespace lock. 216 * 217 * vdev state is protected by spa_vdev_state_enter() / spa_vdev_state_exit(). 218 * Like spa_vdev_enter/exit, these are convenience wrappers -- the actual 219 * locking is, always, based on spa_namespace_lock and spa_config_lock[]. 220 * 221 * spa_rename() is also implemented within this file since it requires 222 * manipulation of the namespace. 223 */ 224 225 static avl_tree_t spa_namespace_avl; 226 kmutex_t spa_namespace_lock; 227 static kcondvar_t spa_namespace_cv; 228 static int spa_active_count; 229 int spa_max_replication_override = SPA_DVAS_PER_BP; 230 231 static kmutex_t spa_spare_lock; 232 static avl_tree_t spa_spare_avl; 233 static kmutex_t spa_l2cache_lock; 234 static avl_tree_t spa_l2cache_avl; 235 236 kmem_cache_t *spa_buffer_pool; 237 int spa_mode_global; 238 239 #ifdef ZFS_DEBUG 240 /* Everything except dprintf and spa is on by default in debug builds */ 241 int zfs_flags = ~(ZFS_DEBUG_DPRINTF | ZFS_DEBUG_SPA); 242 #else 243 int zfs_flags = 0; 244 #endif 245 246 /* 247 * zfs_recover can be set to nonzero to attempt to recover from 248 * otherwise-fatal errors, typically caused by on-disk corruption. When 249 * set, calls to zfs_panic_recover() will turn into warning messages. 250 * This should only be used as a last resort, as it typically results 251 * in leaked space, or worse. 252 */ 253 boolean_t zfs_recover = B_FALSE; 254 255 /* 256 * If destroy encounters an EIO while reading metadata (e.g. indirect 257 * blocks), space referenced by the missing metadata can not be freed. 258 * Normally this causes the background destroy to become "stalled", as 259 * it is unable to make forward progress. While in this stalled state, 260 * all remaining space to free from the error-encountering filesystem is 261 * "temporarily leaked". Set this flag to cause it to ignore the EIO, 262 * permanently leak the space from indirect blocks that can not be read, 263 * and continue to free everything else that it can. 264 * 265 * The default, "stalling" behavior is useful if the storage partially 266 * fails (i.e. some but not all i/os fail), and then later recovers. In 267 * this case, we will be able to continue pool operations while it is 268 * partially failed, and when it recovers, we can continue to free the 269 * space, with no leaks. However, note that this case is actually 270 * fairly rare. 271 * 272 * Typically pools either (a) fail completely (but perhaps temporarily, 273 * e.g. a top-level vdev going offline), or (b) have localized, 274 * permanent errors (e.g. disk returns the wrong data due to bit flip or 275 * firmware bug). In case (a), this setting does not matter because the 276 * pool will be suspended and the sync thread will not be able to make 277 * forward progress regardless. In case (b), because the error is 278 * permanent, the best we can do is leak the minimum amount of space, 279 * which is what setting this flag will do. Therefore, it is reasonable 280 * for this flag to normally be set, but we chose the more conservative 281 * approach of not setting it, so that there is no possibility of 282 * leaking space in the "partial temporary" failure case. 283 */ 284 boolean_t zfs_free_leak_on_eio = B_FALSE; 285 286 /* 287 * Expiration time in milliseconds. This value has two meanings. First it is 288 * used to determine when the spa_deadman() logic should fire. By default the 289 * spa_deadman() will fire if spa_sync() has not completed in 1000 seconds. 290 * Secondly, the value determines if an I/O is considered "hung". Any I/O that 291 * has not completed in zfs_deadman_synctime_ms is considered "hung" resulting 292 * in a system panic. 293 */ 294 uint64_t zfs_deadman_synctime_ms = 1000000ULL; 295 296 /* 297 * Check time in milliseconds. This defines the frequency at which we check 298 * for hung I/O. 299 */ 300 uint64_t zfs_deadman_checktime_ms = 5000ULL; 301 302 /* 303 * Override the zfs deadman behavior via /etc/system. By default the 304 * deadman is enabled except on VMware and sparc deployments. 305 */ 306 int zfs_deadman_enabled = -1; 307 308 /* 309 * The worst case is single-sector max-parity RAID-Z blocks, in which 310 * case the space requirement is exactly (VDEV_RAIDZ_MAXPARITY + 1) 311 * times the size; so just assume that. Add to this the fact that 312 * we can have up to 3 DVAs per bp, and one more factor of 2 because 313 * the block may be dittoed with up to 3 DVAs by ddt_sync(). All together, 314 * the worst case is: 315 * (VDEV_RAIDZ_MAXPARITY + 1) * SPA_DVAS_PER_BP * 2 == 24 316 */ 317 int spa_asize_inflation = 24; 318 319 /* 320 * Normally, we don't allow the last 3.2% (1/(2^spa_slop_shift)) of space in 321 * the pool to be consumed. This ensures that we don't run the pool 322 * completely out of space, due to unaccounted changes (e.g. to the MOS). 323 * It also limits the worst-case time to allocate space. If we have 324 * less than this amount of free space, most ZPL operations (e.g. write, 325 * create) will return ENOSPC. 326 * 327 * Certain operations (e.g. file removal, most administrative actions) can 328 * use half the slop space. They will only return ENOSPC if less than half 329 * the slop space is free. Typically, once the pool has less than the slop 330 * space free, the user will use these operations to free up space in the pool. 331 * These are the operations that call dsl_pool_adjustedsize() with the netfree 332 * argument set to TRUE. 333 * 334 * A very restricted set of operations are always permitted, regardless of 335 * the amount of free space. These are the operations that call 336 * dsl_sync_task(ZFS_SPACE_CHECK_NONE), e.g. "zfs destroy". If these 337 * operations result in a net increase in the amount of space used, 338 * it is possible to run the pool completely out of space, causing it to 339 * be permanently read-only. 340 * 341 * See also the comments in zfs_space_check_t. 342 */ 343 int spa_slop_shift = 5; 344 345 /* 346 * ========================================================================== 347 * SPA config locking 348 * ========================================================================== 349 */ 350 static void 351 spa_config_lock_init(spa_t *spa) 352 { 353 for (int i = 0; i < SCL_LOCKS; i++) { 354 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 355 mutex_init(&scl->scl_lock, NULL, MUTEX_DEFAULT, NULL); 356 cv_init(&scl->scl_cv, NULL, CV_DEFAULT, NULL); 357 refcount_create_untracked(&scl->scl_count); 358 scl->scl_writer = NULL; 359 scl->scl_write_wanted = 0; 360 } 361 } 362 363 static void 364 spa_config_lock_destroy(spa_t *spa) 365 { 366 for (int i = 0; i < SCL_LOCKS; i++) { 367 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 368 mutex_destroy(&scl->scl_lock); 369 cv_destroy(&scl->scl_cv); 370 refcount_destroy(&scl->scl_count); 371 ASSERT(scl->scl_writer == NULL); 372 ASSERT(scl->scl_write_wanted == 0); 373 } 374 } 375 376 int 377 spa_config_tryenter(spa_t *spa, int locks, void *tag, krw_t rw) 378 { 379 for (int i = 0; i < SCL_LOCKS; i++) { 380 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 381 if (!(locks & (1 << i))) 382 continue; 383 mutex_enter(&scl->scl_lock); 384 if (rw == RW_READER) { 385 if (scl->scl_writer || scl->scl_write_wanted) { 386 mutex_exit(&scl->scl_lock); 387 spa_config_exit(spa, locks ^ (1 << i), tag); 388 return (0); 389 } 390 } else { 391 ASSERT(scl->scl_writer != curthread); 392 if (!refcount_is_zero(&scl->scl_count)) { 393 mutex_exit(&scl->scl_lock); 394 spa_config_exit(spa, locks ^ (1 << i), tag); 395 return (0); 396 } 397 scl->scl_writer = curthread; 398 } 399 (void) refcount_add(&scl->scl_count, tag); 400 mutex_exit(&scl->scl_lock); 401 } 402 return (1); 403 } 404 405 void 406 spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw) 407 { 408 int wlocks_held = 0; 409 410 ASSERT3U(SCL_LOCKS, <, sizeof (wlocks_held) * NBBY); 411 412 for (int i = 0; i < SCL_LOCKS; i++) { 413 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 414 if (scl->scl_writer == curthread) 415 wlocks_held |= (1 << i); 416 if (!(locks & (1 << i))) 417 continue; 418 mutex_enter(&scl->scl_lock); 419 if (rw == RW_READER) { 420 while (scl->scl_writer || scl->scl_write_wanted) { 421 cv_wait(&scl->scl_cv, &scl->scl_lock); 422 } 423 } else { 424 ASSERT(scl->scl_writer != curthread); 425 while (!refcount_is_zero(&scl->scl_count)) { 426 scl->scl_write_wanted++; 427 cv_wait(&scl->scl_cv, &scl->scl_lock); 428 scl->scl_write_wanted--; 429 } 430 scl->scl_writer = curthread; 431 } 432 (void) refcount_add(&scl->scl_count, tag); 433 mutex_exit(&scl->scl_lock); 434 } 435 ASSERT(wlocks_held <= locks); 436 } 437 438 void 439 spa_config_exit(spa_t *spa, int locks, void *tag) 440 { 441 for (int i = SCL_LOCKS - 1; i >= 0; i--) { 442 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 443 if (!(locks & (1 << i))) 444 continue; 445 mutex_enter(&scl->scl_lock); 446 ASSERT(!refcount_is_zero(&scl->scl_count)); 447 if (refcount_remove(&scl->scl_count, tag) == 0) { 448 ASSERT(scl->scl_writer == NULL || 449 scl->scl_writer == curthread); 450 scl->scl_writer = NULL; /* OK in either case */ 451 cv_broadcast(&scl->scl_cv); 452 } 453 mutex_exit(&scl->scl_lock); 454 } 455 } 456 457 int 458 spa_config_held(spa_t *spa, int locks, krw_t rw) 459 { 460 int locks_held = 0; 461 462 for (int i = 0; i < SCL_LOCKS; i++) { 463 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 464 if (!(locks & (1 << i))) 465 continue; 466 if ((rw == RW_READER && !refcount_is_zero(&scl->scl_count)) || 467 (rw == RW_WRITER && scl->scl_writer == curthread)) 468 locks_held |= 1 << i; 469 } 470 471 return (locks_held); 472 } 473 474 /* 475 * ========================================================================== 476 * SPA namespace functions 477 * ========================================================================== 478 */ 479 480 /* 481 * Lookup the named spa_t in the AVL tree. The spa_namespace_lock must be held. 482 * Returns NULL if no matching spa_t is found. 483 */ 484 spa_t * 485 spa_lookup(const char *name) 486 { 487 static spa_t search; /* spa_t is large; don't allocate on stack */ 488 spa_t *spa; 489 avl_index_t where; 490 char *cp; 491 492 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 493 494 (void) strlcpy(search.spa_name, name, sizeof (search.spa_name)); 495 496 /* 497 * If it's a full dataset name, figure out the pool name and 498 * just use that. 499 */ 500 cp = strpbrk(search.spa_name, "/@#"); 501 if (cp != NULL) 502 *cp = '\0'; 503 504 spa = avl_find(&spa_namespace_avl, &search, &where); 505 506 return (spa); 507 } 508 509 /* 510 * Fires when spa_sync has not completed within zfs_deadman_synctime_ms. 511 * If the zfs_deadman_enabled flag is set then it inspects all vdev queues 512 * looking for potentially hung I/Os. 513 */ 514 void 515 spa_deadman(void *arg) 516 { 517 spa_t *spa = arg; 518 519 /* 520 * Disable the deadman timer if the pool is suspended. 521 */ 522 if (spa_suspended(spa)) { 523 VERIFY(cyclic_reprogram(spa->spa_deadman_cycid, CY_INFINITY)); 524 return; 525 } 526 527 zfs_dbgmsg("slow spa_sync: started %llu seconds ago, calls %llu", 528 (gethrtime() - spa->spa_sync_starttime) / NANOSEC, 529 ++spa->spa_deadman_calls); 530 if (zfs_deadman_enabled) 531 vdev_deadman(spa->spa_root_vdev); 532 } 533 534 /* 535 * Create an uninitialized spa_t with the given name. Requires 536 * spa_namespace_lock. The caller must ensure that the spa_t doesn't already 537 * exist by calling spa_lookup() first. 538 */ 539 spa_t * 540 spa_add(const char *name, nvlist_t *config, const char *altroot) 541 { 542 spa_t *spa; 543 spa_config_dirent_t *dp; 544 cyc_handler_t hdlr; 545 cyc_time_t when; 546 547 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 548 549 spa = kmem_zalloc(sizeof (spa_t), KM_SLEEP); 550 551 mutex_init(&spa->spa_async_lock, NULL, MUTEX_DEFAULT, NULL); 552 mutex_init(&spa->spa_errlist_lock, NULL, MUTEX_DEFAULT, NULL); 553 mutex_init(&spa->spa_errlog_lock, NULL, MUTEX_DEFAULT, NULL); 554 mutex_init(&spa->spa_history_lock, NULL, MUTEX_DEFAULT, NULL); 555 mutex_init(&spa->spa_proc_lock, NULL, MUTEX_DEFAULT, NULL); 556 mutex_init(&spa->spa_props_lock, NULL, MUTEX_DEFAULT, NULL); 557 mutex_init(&spa->spa_scrub_lock, NULL, MUTEX_DEFAULT, NULL); 558 mutex_init(&spa->spa_suspend_lock, NULL, MUTEX_DEFAULT, NULL); 559 mutex_init(&spa->spa_vdev_top_lock, NULL, MUTEX_DEFAULT, NULL); 560 mutex_init(&spa->spa_iokstat_lock, NULL, MUTEX_DEFAULT, NULL); 561 562 cv_init(&spa->spa_async_cv, NULL, CV_DEFAULT, NULL); 563 cv_init(&spa->spa_proc_cv, NULL, CV_DEFAULT, NULL); 564 cv_init(&spa->spa_scrub_io_cv, NULL, CV_DEFAULT, NULL); 565 cv_init(&spa->spa_suspend_cv, NULL, CV_DEFAULT, NULL); 566 567 for (int t = 0; t < TXG_SIZE; t++) 568 bplist_create(&spa->spa_free_bplist[t]); 569 570 (void) strlcpy(spa->spa_name, name, sizeof (spa->spa_name)); 571 spa->spa_state = POOL_STATE_UNINITIALIZED; 572 spa->spa_freeze_txg = UINT64_MAX; 573 spa->spa_final_txg = UINT64_MAX; 574 spa->spa_load_max_txg = UINT64_MAX; 575 spa->spa_proc = &p0; 576 spa->spa_proc_state = SPA_PROC_NONE; 577 578 hdlr.cyh_func = spa_deadman; 579 hdlr.cyh_arg = spa; 580 hdlr.cyh_level = CY_LOW_LEVEL; 581 582 spa->spa_deadman_synctime = MSEC2NSEC(zfs_deadman_synctime_ms); 583 584 /* 585 * This determines how often we need to check for hung I/Os after 586 * the cyclic has already fired. Since checking for hung I/Os is 587 * an expensive operation we don't want to check too frequently. 588 * Instead wait for 5 seconds before checking again. 589 */ 590 when.cyt_interval = MSEC2NSEC(zfs_deadman_checktime_ms); 591 when.cyt_when = CY_INFINITY; 592 mutex_enter(&cpu_lock); 593 spa->spa_deadman_cycid = cyclic_add(&hdlr, &when); 594 mutex_exit(&cpu_lock); 595 596 refcount_create(&spa->spa_refcount); 597 spa_config_lock_init(spa); 598 599 avl_add(&spa_namespace_avl, spa); 600 601 /* 602 * Set the alternate root, if there is one. 603 */ 604 if (altroot) { 605 spa->spa_root = spa_strdup(altroot); 606 spa_active_count++; 607 } 608 609 /* 610 * Every pool starts with the default cachefile 611 */ 612 list_create(&spa->spa_config_list, sizeof (spa_config_dirent_t), 613 offsetof(spa_config_dirent_t, scd_link)); 614 615 dp = kmem_zalloc(sizeof (spa_config_dirent_t), KM_SLEEP); 616 dp->scd_path = altroot ? NULL : spa_strdup(spa_config_path); 617 list_insert_head(&spa->spa_config_list, dp); 618 619 VERIFY(nvlist_alloc(&spa->spa_load_info, NV_UNIQUE_NAME, 620 KM_SLEEP) == 0); 621 622 if (config != NULL) { 623 nvlist_t *features; 624 625 if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ, 626 &features) == 0) { 627 VERIFY(nvlist_dup(features, &spa->spa_label_features, 628 0) == 0); 629 } 630 631 VERIFY(nvlist_dup(config, &spa->spa_config, 0) == 0); 632 } 633 634 if (spa->spa_label_features == NULL) { 635 VERIFY(nvlist_alloc(&spa->spa_label_features, NV_UNIQUE_NAME, 636 KM_SLEEP) == 0); 637 } 638 639 spa->spa_iokstat = kstat_create("zfs", 0, name, 640 "disk", KSTAT_TYPE_IO, 1, 0); 641 if (spa->spa_iokstat) { 642 spa->spa_iokstat->ks_lock = &spa->spa_iokstat_lock; 643 kstat_install(spa->spa_iokstat); 644 } 645 646 spa->spa_debug = ((zfs_flags & ZFS_DEBUG_SPA) != 0); 647 648 /* 649 * As a pool is being created, treat all features as disabled by 650 * setting SPA_FEATURE_DISABLED for all entries in the feature 651 * refcount cache. 652 */ 653 for (int i = 0; i < SPA_FEATURES; i++) { 654 spa->spa_feat_refcount_cache[i] = SPA_FEATURE_DISABLED; 655 } 656 657 return (spa); 658 } 659 660 /* 661 * Removes a spa_t from the namespace, freeing up any memory used. Requires 662 * spa_namespace_lock. This is called only after the spa_t has been closed and 663 * deactivated. 664 */ 665 void 666 spa_remove(spa_t *spa) 667 { 668 spa_config_dirent_t *dp; 669 670 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 671 ASSERT(spa->spa_state == POOL_STATE_UNINITIALIZED); 672 673 nvlist_free(spa->spa_config_splitting); 674 675 avl_remove(&spa_namespace_avl, spa); 676 cv_broadcast(&spa_namespace_cv); 677 678 if (spa->spa_root) { 679 spa_strfree(spa->spa_root); 680 spa_active_count--; 681 } 682 683 while ((dp = list_head(&spa->spa_config_list)) != NULL) { 684 list_remove(&spa->spa_config_list, dp); 685 if (dp->scd_path != NULL) 686 spa_strfree(dp->scd_path); 687 kmem_free(dp, sizeof (spa_config_dirent_t)); 688 } 689 690 list_destroy(&spa->spa_config_list); 691 692 nvlist_free(spa->spa_label_features); 693 nvlist_free(spa->spa_load_info); 694 spa_config_set(spa, NULL); 695 696 mutex_enter(&cpu_lock); 697 if (spa->spa_deadman_cycid != CYCLIC_NONE) 698 cyclic_remove(spa->spa_deadman_cycid); 699 mutex_exit(&cpu_lock); 700 spa->spa_deadman_cycid = CYCLIC_NONE; 701 702 refcount_destroy(&spa->spa_refcount); 703 704 spa_config_lock_destroy(spa); 705 706 kstat_delete(spa->spa_iokstat); 707 spa->spa_iokstat = NULL; 708 709 for (int t = 0; t < TXG_SIZE; t++) 710 bplist_destroy(&spa->spa_free_bplist[t]); 711 712 cv_destroy(&spa->spa_async_cv); 713 cv_destroy(&spa->spa_proc_cv); 714 cv_destroy(&spa->spa_scrub_io_cv); 715 cv_destroy(&spa->spa_suspend_cv); 716 717 mutex_destroy(&spa->spa_async_lock); 718 mutex_destroy(&spa->spa_errlist_lock); 719 mutex_destroy(&spa->spa_errlog_lock); 720 mutex_destroy(&spa->spa_history_lock); 721 mutex_destroy(&spa->spa_proc_lock); 722 mutex_destroy(&spa->spa_props_lock); 723 mutex_destroy(&spa->spa_scrub_lock); 724 mutex_destroy(&spa->spa_suspend_lock); 725 mutex_destroy(&spa->spa_vdev_top_lock); 726 mutex_destroy(&spa->spa_iokstat_lock); 727 728 kmem_free(spa, sizeof (spa_t)); 729 } 730 731 /* 732 * Given a pool, return the next pool in the namespace, or NULL if there is 733 * none. If 'prev' is NULL, return the first pool. 734 */ 735 spa_t * 736 spa_next(spa_t *prev) 737 { 738 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 739 740 if (prev) 741 return (AVL_NEXT(&spa_namespace_avl, prev)); 742 else 743 return (avl_first(&spa_namespace_avl)); 744 } 745 746 /* 747 * ========================================================================== 748 * SPA refcount functions 749 * ========================================================================== 750 */ 751 752 /* 753 * Add a reference to the given spa_t. Must have at least one reference, or 754 * have the namespace lock held. 755 */ 756 void 757 spa_open_ref(spa_t *spa, void *tag) 758 { 759 ASSERT(refcount_count(&spa->spa_refcount) >= spa->spa_minref || 760 MUTEX_HELD(&spa_namespace_lock)); 761 (void) refcount_add(&spa->spa_refcount, tag); 762 } 763 764 /* 765 * Remove a reference to the given spa_t. Must have at least one reference, or 766 * have the namespace lock held. 767 */ 768 void 769 spa_close(spa_t *spa, void *tag) 770 { 771 ASSERT(refcount_count(&spa->spa_refcount) > spa->spa_minref || 772 MUTEX_HELD(&spa_namespace_lock)); 773 (void) refcount_remove(&spa->spa_refcount, tag); 774 } 775 776 /* 777 * Check to see if the spa refcount is zero. Must be called with 778 * spa_namespace_lock held. We really compare against spa_minref, which is the 779 * number of references acquired when opening a pool 780 */ 781 boolean_t 782 spa_refcount_zero(spa_t *spa) 783 { 784 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 785 786 return (refcount_count(&spa->spa_refcount) == spa->spa_minref); 787 } 788 789 /* 790 * ========================================================================== 791 * SPA spare and l2cache tracking 792 * ========================================================================== 793 */ 794 795 /* 796 * Hot spares and cache devices are tracked using the same code below, 797 * for 'auxiliary' devices. 798 */ 799 800 typedef struct spa_aux { 801 uint64_t aux_guid; 802 uint64_t aux_pool; 803 avl_node_t aux_avl; 804 int aux_count; 805 } spa_aux_t; 806 807 static int 808 spa_aux_compare(const void *a, const void *b) 809 { 810 const spa_aux_t *sa = a; 811 const spa_aux_t *sb = b; 812 813 if (sa->aux_guid < sb->aux_guid) 814 return (-1); 815 else if (sa->aux_guid > sb->aux_guid) 816 return (1); 817 else 818 return (0); 819 } 820 821 void 822 spa_aux_add(vdev_t *vd, avl_tree_t *avl) 823 { 824 avl_index_t where; 825 spa_aux_t search; 826 spa_aux_t *aux; 827 828 search.aux_guid = vd->vdev_guid; 829 if ((aux = avl_find(avl, &search, &where)) != NULL) { 830 aux->aux_count++; 831 } else { 832 aux = kmem_zalloc(sizeof (spa_aux_t), KM_SLEEP); 833 aux->aux_guid = vd->vdev_guid; 834 aux->aux_count = 1; 835 avl_insert(avl, aux, where); 836 } 837 } 838 839 void 840 spa_aux_remove(vdev_t *vd, avl_tree_t *avl) 841 { 842 spa_aux_t search; 843 spa_aux_t *aux; 844 avl_index_t where; 845 846 search.aux_guid = vd->vdev_guid; 847 aux = avl_find(avl, &search, &where); 848 849 ASSERT(aux != NULL); 850 851 if (--aux->aux_count == 0) { 852 avl_remove(avl, aux); 853 kmem_free(aux, sizeof (spa_aux_t)); 854 } else if (aux->aux_pool == spa_guid(vd->vdev_spa)) { 855 aux->aux_pool = 0ULL; 856 } 857 } 858 859 boolean_t 860 spa_aux_exists(uint64_t guid, uint64_t *pool, int *refcnt, avl_tree_t *avl) 861 { 862 spa_aux_t search, *found; 863 864 search.aux_guid = guid; 865 found = avl_find(avl, &search, NULL); 866 867 if (pool) { 868 if (found) 869 *pool = found->aux_pool; 870 else 871 *pool = 0ULL; 872 } 873 874 if (refcnt) { 875 if (found) 876 *refcnt = found->aux_count; 877 else 878 *refcnt = 0; 879 } 880 881 return (found != NULL); 882 } 883 884 void 885 spa_aux_activate(vdev_t *vd, avl_tree_t *avl) 886 { 887 spa_aux_t search, *found; 888 avl_index_t where; 889 890 search.aux_guid = vd->vdev_guid; 891 found = avl_find(avl, &search, &where); 892 ASSERT(found != NULL); 893 ASSERT(found->aux_pool == 0ULL); 894 895 found->aux_pool = spa_guid(vd->vdev_spa); 896 } 897 898 /* 899 * Spares are tracked globally due to the following constraints: 900 * 901 * - A spare may be part of multiple pools. 902 * - A spare may be added to a pool even if it's actively in use within 903 * another pool. 904 * - A spare in use in any pool can only be the source of a replacement if 905 * the target is a spare in the same pool. 906 * 907 * We keep track of all spares on the system through the use of a reference 908 * counted AVL tree. When a vdev is added as a spare, or used as a replacement 909 * spare, then we bump the reference count in the AVL tree. In addition, we set 910 * the 'vdev_isspare' member to indicate that the device is a spare (active or 911 * inactive). When a spare is made active (used to replace a device in the 912 * pool), we also keep track of which pool its been made a part of. 913 * 914 * The 'spa_spare_lock' protects the AVL tree. These functions are normally 915 * called under the spa_namespace lock as part of vdev reconfiguration. The 916 * separate spare lock exists for the status query path, which does not need to 917 * be completely consistent with respect to other vdev configuration changes. 918 */ 919 920 static int 921 spa_spare_compare(const void *a, const void *b) 922 { 923 return (spa_aux_compare(a, b)); 924 } 925 926 void 927 spa_spare_add(vdev_t *vd) 928 { 929 mutex_enter(&spa_spare_lock); 930 ASSERT(!vd->vdev_isspare); 931 spa_aux_add(vd, &spa_spare_avl); 932 vd->vdev_isspare = B_TRUE; 933 mutex_exit(&spa_spare_lock); 934 } 935 936 void 937 spa_spare_remove(vdev_t *vd) 938 { 939 mutex_enter(&spa_spare_lock); 940 ASSERT(vd->vdev_isspare); 941 spa_aux_remove(vd, &spa_spare_avl); 942 vd->vdev_isspare = B_FALSE; 943 mutex_exit(&spa_spare_lock); 944 } 945 946 boolean_t 947 spa_spare_exists(uint64_t guid, uint64_t *pool, int *refcnt) 948 { 949 boolean_t found; 950 951 mutex_enter(&spa_spare_lock); 952 found = spa_aux_exists(guid, pool, refcnt, &spa_spare_avl); 953 mutex_exit(&spa_spare_lock); 954 955 return (found); 956 } 957 958 void 959 spa_spare_activate(vdev_t *vd) 960 { 961 mutex_enter(&spa_spare_lock); 962 ASSERT(vd->vdev_isspare); 963 spa_aux_activate(vd, &spa_spare_avl); 964 mutex_exit(&spa_spare_lock); 965 } 966 967 /* 968 * Level 2 ARC devices are tracked globally for the same reasons as spares. 969 * Cache devices currently only support one pool per cache device, and so 970 * for these devices the aux reference count is currently unused beyond 1. 971 */ 972 973 static int 974 spa_l2cache_compare(const void *a, const void *b) 975 { 976 return (spa_aux_compare(a, b)); 977 } 978 979 void 980 spa_l2cache_add(vdev_t *vd) 981 { 982 mutex_enter(&spa_l2cache_lock); 983 ASSERT(!vd->vdev_isl2cache); 984 spa_aux_add(vd, &spa_l2cache_avl); 985 vd->vdev_isl2cache = B_TRUE; 986 mutex_exit(&spa_l2cache_lock); 987 } 988 989 void 990 spa_l2cache_remove(vdev_t *vd) 991 { 992 mutex_enter(&spa_l2cache_lock); 993 ASSERT(vd->vdev_isl2cache); 994 spa_aux_remove(vd, &spa_l2cache_avl); 995 vd->vdev_isl2cache = B_FALSE; 996 mutex_exit(&spa_l2cache_lock); 997 } 998 999 boolean_t 1000 spa_l2cache_exists(uint64_t guid, uint64_t *pool) 1001 { 1002 boolean_t found; 1003 1004 mutex_enter(&spa_l2cache_lock); 1005 found = spa_aux_exists(guid, pool, NULL, &spa_l2cache_avl); 1006 mutex_exit(&spa_l2cache_lock); 1007 1008 return (found); 1009 } 1010 1011 void 1012 spa_l2cache_activate(vdev_t *vd) 1013 { 1014 mutex_enter(&spa_l2cache_lock); 1015 ASSERT(vd->vdev_isl2cache); 1016 spa_aux_activate(vd, &spa_l2cache_avl); 1017 mutex_exit(&spa_l2cache_lock); 1018 } 1019 1020 /* 1021 * ========================================================================== 1022 * SPA vdev locking 1023 * ========================================================================== 1024 */ 1025 1026 /* 1027 * Lock the given spa_t for the purpose of adding or removing a vdev. 1028 * Grabs the global spa_namespace_lock plus the spa config lock for writing. 1029 * It returns the next transaction group for the spa_t. 1030 */ 1031 uint64_t 1032 spa_vdev_enter(spa_t *spa) 1033 { 1034 mutex_enter(&spa->spa_vdev_top_lock); 1035 mutex_enter(&spa_namespace_lock); 1036 return (spa_vdev_config_enter(spa)); 1037 } 1038 1039 /* 1040 * Internal implementation for spa_vdev_enter(). Used when a vdev 1041 * operation requires multiple syncs (i.e. removing a device) while 1042 * keeping the spa_namespace_lock held. 1043 */ 1044 uint64_t 1045 spa_vdev_config_enter(spa_t *spa) 1046 { 1047 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1048 1049 spa_config_enter(spa, SCL_ALL, spa, RW_WRITER); 1050 1051 return (spa_last_synced_txg(spa) + 1); 1052 } 1053 1054 /* 1055 * Used in combination with spa_vdev_config_enter() to allow the syncing 1056 * of multiple transactions without releasing the spa_namespace_lock. 1057 */ 1058 void 1059 spa_vdev_config_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error, char *tag) 1060 { 1061 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1062 1063 int config_changed = B_FALSE; 1064 1065 ASSERT(txg > spa_last_synced_txg(spa)); 1066 1067 spa->spa_pending_vdev = NULL; 1068 1069 /* 1070 * Reassess the DTLs. 1071 */ 1072 vdev_dtl_reassess(spa->spa_root_vdev, 0, 0, B_FALSE); 1073 1074 if (error == 0 && !list_is_empty(&spa->spa_config_dirty_list)) { 1075 config_changed = B_TRUE; 1076 spa->spa_config_generation++; 1077 } 1078 1079 /* 1080 * Verify the metaslab classes. 1081 */ 1082 ASSERT(metaslab_class_validate(spa_normal_class(spa)) == 0); 1083 ASSERT(metaslab_class_validate(spa_log_class(spa)) == 0); 1084 1085 spa_config_exit(spa, SCL_ALL, spa); 1086 1087 /* 1088 * Panic the system if the specified tag requires it. This 1089 * is useful for ensuring that configurations are updated 1090 * transactionally. 1091 */ 1092 if (zio_injection_enabled) 1093 zio_handle_panic_injection(spa, tag, 0); 1094 1095 /* 1096 * Note: this txg_wait_synced() is important because it ensures 1097 * that there won't be more than one config change per txg. 1098 * This allows us to use the txg as the generation number. 1099 */ 1100 if (error == 0) 1101 txg_wait_synced(spa->spa_dsl_pool, txg); 1102 1103 if (vd != NULL) { 1104 ASSERT(!vd->vdev_detached || vd->vdev_dtl_sm == NULL); 1105 spa_config_enter(spa, SCL_ALL, spa, RW_WRITER); 1106 vdev_free(vd); 1107 spa_config_exit(spa, SCL_ALL, spa); 1108 } 1109 1110 /* 1111 * If the config changed, update the config cache. 1112 */ 1113 if (config_changed) 1114 spa_config_sync(spa, B_FALSE, B_TRUE); 1115 } 1116 1117 /* 1118 * Unlock the spa_t after adding or removing a vdev. Besides undoing the 1119 * locking of spa_vdev_enter(), we also want make sure the transactions have 1120 * synced to disk, and then update the global configuration cache with the new 1121 * information. 1122 */ 1123 int 1124 spa_vdev_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error) 1125 { 1126 spa_vdev_config_exit(spa, vd, txg, error, FTAG); 1127 mutex_exit(&spa_namespace_lock); 1128 mutex_exit(&spa->spa_vdev_top_lock); 1129 1130 return (error); 1131 } 1132 1133 /* 1134 * Lock the given spa_t for the purpose of changing vdev state. 1135 */ 1136 void 1137 spa_vdev_state_enter(spa_t *spa, int oplocks) 1138 { 1139 int locks = SCL_STATE_ALL | oplocks; 1140 1141 /* 1142 * Root pools may need to read of the underlying devfs filesystem 1143 * when opening up a vdev. Unfortunately if we're holding the 1144 * SCL_ZIO lock it will result in a deadlock when we try to issue 1145 * the read from the root filesystem. Instead we "prefetch" 1146 * the associated vnodes that we need prior to opening the 1147 * underlying devices and cache them so that we can prevent 1148 * any I/O when we are doing the actual open. 1149 */ 1150 if (spa_is_root(spa)) { 1151 int low = locks & ~(SCL_ZIO - 1); 1152 int high = locks & ~low; 1153 1154 spa_config_enter(spa, high, spa, RW_WRITER); 1155 vdev_hold(spa->spa_root_vdev); 1156 spa_config_enter(spa, low, spa, RW_WRITER); 1157 } else { 1158 spa_config_enter(spa, locks, spa, RW_WRITER); 1159 } 1160 spa->spa_vdev_locks = locks; 1161 } 1162 1163 int 1164 spa_vdev_state_exit(spa_t *spa, vdev_t *vd, int error) 1165 { 1166 boolean_t config_changed = B_FALSE; 1167 1168 if (vd != NULL || error == 0) 1169 vdev_dtl_reassess(vd ? vd->vdev_top : spa->spa_root_vdev, 1170 0, 0, B_FALSE); 1171 1172 if (vd != NULL) { 1173 vdev_state_dirty(vd->vdev_top); 1174 config_changed = B_TRUE; 1175 spa->spa_config_generation++; 1176 } 1177 1178 if (spa_is_root(spa)) 1179 vdev_rele(spa->spa_root_vdev); 1180 1181 ASSERT3U(spa->spa_vdev_locks, >=, SCL_STATE_ALL); 1182 spa_config_exit(spa, spa->spa_vdev_locks, spa); 1183 1184 /* 1185 * If anything changed, wait for it to sync. This ensures that, 1186 * from the system administrator's perspective, zpool(1M) commands 1187 * are synchronous. This is important for things like zpool offline: 1188 * when the command completes, you expect no further I/O from ZFS. 1189 */ 1190 if (vd != NULL) 1191 txg_wait_synced(spa->spa_dsl_pool, 0); 1192 1193 /* 1194 * If the config changed, update the config cache. 1195 */ 1196 if (config_changed) { 1197 mutex_enter(&spa_namespace_lock); 1198 spa_config_sync(spa, B_FALSE, B_TRUE); 1199 mutex_exit(&spa_namespace_lock); 1200 } 1201 1202 return (error); 1203 } 1204 1205 /* 1206 * ========================================================================== 1207 * Miscellaneous functions 1208 * ========================================================================== 1209 */ 1210 1211 void 1212 spa_activate_mos_feature(spa_t *spa, const char *feature, dmu_tx_t *tx) 1213 { 1214 if (!nvlist_exists(spa->spa_label_features, feature)) { 1215 fnvlist_add_boolean(spa->spa_label_features, feature); 1216 /* 1217 * When we are creating the pool (tx_txg==TXG_INITIAL), we can't 1218 * dirty the vdev config because lock SCL_CONFIG is not held. 1219 * Thankfully, in this case we don't need to dirty the config 1220 * because it will be written out anyway when we finish 1221 * creating the pool. 1222 */ 1223 if (tx->tx_txg != TXG_INITIAL) 1224 vdev_config_dirty(spa->spa_root_vdev); 1225 } 1226 } 1227 1228 void 1229 spa_deactivate_mos_feature(spa_t *spa, const char *feature) 1230 { 1231 if (nvlist_remove_all(spa->spa_label_features, feature) == 0) 1232 vdev_config_dirty(spa->spa_root_vdev); 1233 } 1234 1235 /* 1236 * Rename a spa_t. 1237 */ 1238 int 1239 spa_rename(const char *name, const char *newname) 1240 { 1241 spa_t *spa; 1242 int err; 1243 1244 /* 1245 * Lookup the spa_t and grab the config lock for writing. We need to 1246 * actually open the pool so that we can sync out the necessary labels. 1247 * It's OK to call spa_open() with the namespace lock held because we 1248 * allow recursive calls for other reasons. 1249 */ 1250 mutex_enter(&spa_namespace_lock); 1251 if ((err = spa_open(name, &spa, FTAG)) != 0) { 1252 mutex_exit(&spa_namespace_lock); 1253 return (err); 1254 } 1255 1256 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1257 1258 avl_remove(&spa_namespace_avl, spa); 1259 (void) strlcpy(spa->spa_name, newname, sizeof (spa->spa_name)); 1260 avl_add(&spa_namespace_avl, spa); 1261 1262 /* 1263 * Sync all labels to disk with the new names by marking the root vdev 1264 * dirty and waiting for it to sync. It will pick up the new pool name 1265 * during the sync. 1266 */ 1267 vdev_config_dirty(spa->spa_root_vdev); 1268 1269 spa_config_exit(spa, SCL_ALL, FTAG); 1270 1271 txg_wait_synced(spa->spa_dsl_pool, 0); 1272 1273 /* 1274 * Sync the updated config cache. 1275 */ 1276 spa_config_sync(spa, B_FALSE, B_TRUE); 1277 1278 spa_close(spa, FTAG); 1279 1280 mutex_exit(&spa_namespace_lock); 1281 1282 return (0); 1283 } 1284 1285 /* 1286 * Return the spa_t associated with given pool_guid, if it exists. If 1287 * device_guid is non-zero, determine whether the pool exists *and* contains 1288 * a device with the specified device_guid. 1289 */ 1290 spa_t * 1291 spa_by_guid(uint64_t pool_guid, uint64_t device_guid) 1292 { 1293 spa_t *spa; 1294 avl_tree_t *t = &spa_namespace_avl; 1295 1296 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1297 1298 for (spa = avl_first(t); spa != NULL; spa = AVL_NEXT(t, spa)) { 1299 if (spa->spa_state == POOL_STATE_UNINITIALIZED) 1300 continue; 1301 if (spa->spa_root_vdev == NULL) 1302 continue; 1303 if (spa_guid(spa) == pool_guid) { 1304 if (device_guid == 0) 1305 break; 1306 1307 if (vdev_lookup_by_guid(spa->spa_root_vdev, 1308 device_guid) != NULL) 1309 break; 1310 1311 /* 1312 * Check any devices we may be in the process of adding. 1313 */ 1314 if (spa->spa_pending_vdev) { 1315 if (vdev_lookup_by_guid(spa->spa_pending_vdev, 1316 device_guid) != NULL) 1317 break; 1318 } 1319 } 1320 } 1321 1322 return (spa); 1323 } 1324 1325 /* 1326 * Determine whether a pool with the given pool_guid exists. 1327 */ 1328 boolean_t 1329 spa_guid_exists(uint64_t pool_guid, uint64_t device_guid) 1330 { 1331 return (spa_by_guid(pool_guid, device_guid) != NULL); 1332 } 1333 1334 char * 1335 spa_strdup(const char *s) 1336 { 1337 size_t len; 1338 char *new; 1339 1340 len = strlen(s); 1341 new = kmem_alloc(len + 1, KM_SLEEP); 1342 bcopy(s, new, len); 1343 new[len] = '\0'; 1344 1345 return (new); 1346 } 1347 1348 void 1349 spa_strfree(char *s) 1350 { 1351 kmem_free(s, strlen(s) + 1); 1352 } 1353 1354 uint64_t 1355 spa_get_random(uint64_t range) 1356 { 1357 uint64_t r; 1358 1359 ASSERT(range != 0); 1360 1361 (void) random_get_pseudo_bytes((void *)&r, sizeof (uint64_t)); 1362 1363 return (r % range); 1364 } 1365 1366 uint64_t 1367 spa_generate_guid(spa_t *spa) 1368 { 1369 uint64_t guid = spa_get_random(-1ULL); 1370 1371 if (spa != NULL) { 1372 while (guid == 0 || spa_guid_exists(spa_guid(spa), guid)) 1373 guid = spa_get_random(-1ULL); 1374 } else { 1375 while (guid == 0 || spa_guid_exists(guid, 0)) 1376 guid = spa_get_random(-1ULL); 1377 } 1378 1379 return (guid); 1380 } 1381 1382 void 1383 snprintf_blkptr(char *buf, size_t buflen, const blkptr_t *bp) 1384 { 1385 char type[256]; 1386 char *checksum = NULL; 1387 char *compress = NULL; 1388 1389 if (bp != NULL) { 1390 if (BP_GET_TYPE(bp) & DMU_OT_NEWTYPE) { 1391 dmu_object_byteswap_t bswap = 1392 DMU_OT_BYTESWAP(BP_GET_TYPE(bp)); 1393 (void) snprintf(type, sizeof (type), "bswap %s %s", 1394 DMU_OT_IS_METADATA(BP_GET_TYPE(bp)) ? 1395 "metadata" : "data", 1396 dmu_ot_byteswap[bswap].ob_name); 1397 } else { 1398 (void) strlcpy(type, dmu_ot[BP_GET_TYPE(bp)].ot_name, 1399 sizeof (type)); 1400 } 1401 if (!BP_IS_EMBEDDED(bp)) { 1402 checksum = 1403 zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_name; 1404 } 1405 compress = zio_compress_table[BP_GET_COMPRESS(bp)].ci_name; 1406 } 1407 1408 SNPRINTF_BLKPTR(snprintf, ' ', buf, buflen, bp, type, checksum, 1409 compress); 1410 } 1411 1412 void 1413 spa_freeze(spa_t *spa) 1414 { 1415 uint64_t freeze_txg = 0; 1416 1417 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1418 if (spa->spa_freeze_txg == UINT64_MAX) { 1419 freeze_txg = spa_last_synced_txg(spa) + TXG_SIZE; 1420 spa->spa_freeze_txg = freeze_txg; 1421 } 1422 spa_config_exit(spa, SCL_ALL, FTAG); 1423 if (freeze_txg != 0) 1424 txg_wait_synced(spa_get_dsl(spa), freeze_txg); 1425 } 1426 1427 void 1428 zfs_panic_recover(const char *fmt, ...) 1429 { 1430 va_list adx; 1431 1432 va_start(adx, fmt); 1433 vcmn_err(zfs_recover ? CE_WARN : CE_PANIC, fmt, adx); 1434 va_end(adx); 1435 } 1436 1437 /* 1438 * This is a stripped-down version of strtoull, suitable only for converting 1439 * lowercase hexadecimal numbers that don't overflow. 1440 */ 1441 uint64_t 1442 strtonum(const char *str, char **nptr) 1443 { 1444 uint64_t val = 0; 1445 char c; 1446 int digit; 1447 1448 while ((c = *str) != '\0') { 1449 if (c >= '0' && c <= '9') 1450 digit = c - '0'; 1451 else if (c >= 'a' && c <= 'f') 1452 digit = 10 + c - 'a'; 1453 else 1454 break; 1455 1456 val *= 16; 1457 val += digit; 1458 1459 str++; 1460 } 1461 1462 if (nptr) 1463 *nptr = (char *)str; 1464 1465 return (val); 1466 } 1467 1468 /* 1469 * ========================================================================== 1470 * Accessor functions 1471 * ========================================================================== 1472 */ 1473 1474 boolean_t 1475 spa_shutting_down(spa_t *spa) 1476 { 1477 return (spa->spa_async_suspended); 1478 } 1479 1480 dsl_pool_t * 1481 spa_get_dsl(spa_t *spa) 1482 { 1483 return (spa->spa_dsl_pool); 1484 } 1485 1486 boolean_t 1487 spa_is_initializing(spa_t *spa) 1488 { 1489 return (spa->spa_is_initializing); 1490 } 1491 1492 blkptr_t * 1493 spa_get_rootblkptr(spa_t *spa) 1494 { 1495 return (&spa->spa_ubsync.ub_rootbp); 1496 } 1497 1498 void 1499 spa_set_rootblkptr(spa_t *spa, const blkptr_t *bp) 1500 { 1501 spa->spa_uberblock.ub_rootbp = *bp; 1502 } 1503 1504 void 1505 spa_altroot(spa_t *spa, char *buf, size_t buflen) 1506 { 1507 if (spa->spa_root == NULL) 1508 buf[0] = '\0'; 1509 else 1510 (void) strncpy(buf, spa->spa_root, buflen); 1511 } 1512 1513 int 1514 spa_sync_pass(spa_t *spa) 1515 { 1516 return (spa->spa_sync_pass); 1517 } 1518 1519 char * 1520 spa_name(spa_t *spa) 1521 { 1522 return (spa->spa_name); 1523 } 1524 1525 uint64_t 1526 spa_guid(spa_t *spa) 1527 { 1528 dsl_pool_t *dp = spa_get_dsl(spa); 1529 uint64_t guid; 1530 1531 /* 1532 * If we fail to parse the config during spa_load(), we can go through 1533 * the error path (which posts an ereport) and end up here with no root 1534 * vdev. We stash the original pool guid in 'spa_config_guid' to handle 1535 * this case. 1536 */ 1537 if (spa->spa_root_vdev == NULL) 1538 return (spa->spa_config_guid); 1539 1540 guid = spa->spa_last_synced_guid != 0 ? 1541 spa->spa_last_synced_guid : spa->spa_root_vdev->vdev_guid; 1542 1543 /* 1544 * Return the most recently synced out guid unless we're 1545 * in syncing context. 1546 */ 1547 if (dp && dsl_pool_sync_context(dp)) 1548 return (spa->spa_root_vdev->vdev_guid); 1549 else 1550 return (guid); 1551 } 1552 1553 uint64_t 1554 spa_load_guid(spa_t *spa) 1555 { 1556 /* 1557 * This is a GUID that exists solely as a reference for the 1558 * purposes of the arc. It is generated at load time, and 1559 * is never written to persistent storage. 1560 */ 1561 return (spa->spa_load_guid); 1562 } 1563 1564 uint64_t 1565 spa_last_synced_txg(spa_t *spa) 1566 { 1567 return (spa->spa_ubsync.ub_txg); 1568 } 1569 1570 uint64_t 1571 spa_first_txg(spa_t *spa) 1572 { 1573 return (spa->spa_first_txg); 1574 } 1575 1576 uint64_t 1577 spa_syncing_txg(spa_t *spa) 1578 { 1579 return (spa->spa_syncing_txg); 1580 } 1581 1582 pool_state_t 1583 spa_state(spa_t *spa) 1584 { 1585 return (spa->spa_state); 1586 } 1587 1588 spa_load_state_t 1589 spa_load_state(spa_t *spa) 1590 { 1591 return (spa->spa_load_state); 1592 } 1593 1594 uint64_t 1595 spa_freeze_txg(spa_t *spa) 1596 { 1597 return (spa->spa_freeze_txg); 1598 } 1599 1600 /* ARGSUSED */ 1601 uint64_t 1602 spa_get_asize(spa_t *spa, uint64_t lsize) 1603 { 1604 return (lsize * spa_asize_inflation); 1605 } 1606 1607 /* 1608 * Return the amount of slop space in bytes. It is 1/32 of the pool (3.2%), 1609 * or at least 32MB. 1610 * 1611 * See the comment above spa_slop_shift for details. 1612 */ 1613 uint64_t 1614 spa_get_slop_space(spa_t *spa) { 1615 uint64_t space = spa_get_dspace(spa); 1616 return (MAX(space >> spa_slop_shift, SPA_MINDEVSIZE >> 1)); 1617 } 1618 1619 uint64_t 1620 spa_get_dspace(spa_t *spa) 1621 { 1622 return (spa->spa_dspace); 1623 } 1624 1625 void 1626 spa_update_dspace(spa_t *spa) 1627 { 1628 spa->spa_dspace = metaslab_class_get_dspace(spa_normal_class(spa)) + 1629 ddt_get_dedup_dspace(spa); 1630 } 1631 1632 /* 1633 * Return the failure mode that has been set to this pool. The default 1634 * behavior will be to block all I/Os when a complete failure occurs. 1635 */ 1636 uint8_t 1637 spa_get_failmode(spa_t *spa) 1638 { 1639 return (spa->spa_failmode); 1640 } 1641 1642 boolean_t 1643 spa_suspended(spa_t *spa) 1644 { 1645 return (spa->spa_suspended); 1646 } 1647 1648 uint64_t 1649 spa_version(spa_t *spa) 1650 { 1651 return (spa->spa_ubsync.ub_version); 1652 } 1653 1654 boolean_t 1655 spa_deflate(spa_t *spa) 1656 { 1657 return (spa->spa_deflate); 1658 } 1659 1660 metaslab_class_t * 1661 spa_normal_class(spa_t *spa) 1662 { 1663 return (spa->spa_normal_class); 1664 } 1665 1666 metaslab_class_t * 1667 spa_log_class(spa_t *spa) 1668 { 1669 return (spa->spa_log_class); 1670 } 1671 1672 int 1673 spa_max_replication(spa_t *spa) 1674 { 1675 /* 1676 * As of SPA_VERSION == SPA_VERSION_DITTO_BLOCKS, we are able to 1677 * handle BPs with more than one DVA allocated. Set our max 1678 * replication level accordingly. 1679 */ 1680 if (spa_version(spa) < SPA_VERSION_DITTO_BLOCKS) 1681 return (1); 1682 return (MIN(SPA_DVAS_PER_BP, spa_max_replication_override)); 1683 } 1684 1685 int 1686 spa_prev_software_version(spa_t *spa) 1687 { 1688 return (spa->spa_prev_software_version); 1689 } 1690 1691 uint64_t 1692 spa_deadman_synctime(spa_t *spa) 1693 { 1694 return (spa->spa_deadman_synctime); 1695 } 1696 1697 uint64_t 1698 dva_get_dsize_sync(spa_t *spa, const dva_t *dva) 1699 { 1700 uint64_t asize = DVA_GET_ASIZE(dva); 1701 uint64_t dsize = asize; 1702 1703 ASSERT(spa_config_held(spa, SCL_ALL, RW_READER) != 0); 1704 1705 if (asize != 0 && spa->spa_deflate) { 1706 vdev_t *vd = vdev_lookup_top(spa, DVA_GET_VDEV(dva)); 1707 dsize = (asize >> SPA_MINBLOCKSHIFT) * vd->vdev_deflate_ratio; 1708 } 1709 1710 return (dsize); 1711 } 1712 1713 uint64_t 1714 bp_get_dsize_sync(spa_t *spa, const blkptr_t *bp) 1715 { 1716 uint64_t dsize = 0; 1717 1718 for (int d = 0; d < BP_GET_NDVAS(bp); d++) 1719 dsize += dva_get_dsize_sync(spa, &bp->blk_dva[d]); 1720 1721 return (dsize); 1722 } 1723 1724 uint64_t 1725 bp_get_dsize(spa_t *spa, const blkptr_t *bp) 1726 { 1727 uint64_t dsize = 0; 1728 1729 spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); 1730 1731 for (int d = 0; d < BP_GET_NDVAS(bp); d++) 1732 dsize += dva_get_dsize_sync(spa, &bp->blk_dva[d]); 1733 1734 spa_config_exit(spa, SCL_VDEV, FTAG); 1735 1736 return (dsize); 1737 } 1738 1739 /* 1740 * ========================================================================== 1741 * Initialization and Termination 1742 * ========================================================================== 1743 */ 1744 1745 static int 1746 spa_name_compare(const void *a1, const void *a2) 1747 { 1748 const spa_t *s1 = a1; 1749 const spa_t *s2 = a2; 1750 int s; 1751 1752 s = strcmp(s1->spa_name, s2->spa_name); 1753 if (s > 0) 1754 return (1); 1755 if (s < 0) 1756 return (-1); 1757 return (0); 1758 } 1759 1760 int 1761 spa_busy(void) 1762 { 1763 return (spa_active_count); 1764 } 1765 1766 void 1767 spa_boot_init() 1768 { 1769 spa_config_load(); 1770 } 1771 1772 void 1773 spa_init(int mode) 1774 { 1775 mutex_init(&spa_namespace_lock, NULL, MUTEX_DEFAULT, NULL); 1776 mutex_init(&spa_spare_lock, NULL, MUTEX_DEFAULT, NULL); 1777 mutex_init(&spa_l2cache_lock, NULL, MUTEX_DEFAULT, NULL); 1778 cv_init(&spa_namespace_cv, NULL, CV_DEFAULT, NULL); 1779 1780 avl_create(&spa_namespace_avl, spa_name_compare, sizeof (spa_t), 1781 offsetof(spa_t, spa_avl)); 1782 1783 avl_create(&spa_spare_avl, spa_spare_compare, sizeof (spa_aux_t), 1784 offsetof(spa_aux_t, aux_avl)); 1785 1786 avl_create(&spa_l2cache_avl, spa_l2cache_compare, sizeof (spa_aux_t), 1787 offsetof(spa_aux_t, aux_avl)); 1788 1789 spa_mode_global = mode; 1790 1791 #ifdef _KERNEL 1792 spa_arch_init(); 1793 #else 1794 if (spa_mode_global != FREAD && dprintf_find_string("watch")) { 1795 arc_procfd = open("/proc/self/ctl", O_WRONLY); 1796 if (arc_procfd == -1) { 1797 perror("could not enable watchpoints: " 1798 "opening /proc/self/ctl failed: "); 1799 } else { 1800 arc_watch = B_TRUE; 1801 } 1802 } 1803 #endif 1804 1805 refcount_init(); 1806 unique_init(); 1807 range_tree_init(); 1808 zio_init(); 1809 dmu_init(); 1810 zil_init(); 1811 vdev_cache_stat_init(); 1812 zfs_prop_init(); 1813 zpool_prop_init(); 1814 zpool_feature_init(); 1815 spa_config_load(); 1816 l2arc_start(); 1817 } 1818 1819 void 1820 spa_fini(void) 1821 { 1822 l2arc_stop(); 1823 1824 spa_evict_all(); 1825 1826 vdev_cache_stat_fini(); 1827 zil_fini(); 1828 dmu_fini(); 1829 zio_fini(); 1830 range_tree_fini(); 1831 unique_fini(); 1832 refcount_fini(); 1833 1834 avl_destroy(&spa_namespace_avl); 1835 avl_destroy(&spa_spare_avl); 1836 avl_destroy(&spa_l2cache_avl); 1837 1838 cv_destroy(&spa_namespace_cv); 1839 mutex_destroy(&spa_namespace_lock); 1840 mutex_destroy(&spa_spare_lock); 1841 mutex_destroy(&spa_l2cache_lock); 1842 } 1843 1844 /* 1845 * Return whether this pool has slogs. No locking needed. 1846 * It's not a problem if the wrong answer is returned as it's only for 1847 * performance and not correctness 1848 */ 1849 boolean_t 1850 spa_has_slogs(spa_t *spa) 1851 { 1852 return (spa->spa_log_class->mc_rotor != NULL); 1853 } 1854 1855 spa_log_state_t 1856 spa_get_log_state(spa_t *spa) 1857 { 1858 return (spa->spa_log_state); 1859 } 1860 1861 void 1862 spa_set_log_state(spa_t *spa, spa_log_state_t state) 1863 { 1864 spa->spa_log_state = state; 1865 } 1866 1867 boolean_t 1868 spa_is_root(spa_t *spa) 1869 { 1870 return (spa->spa_is_root); 1871 } 1872 1873 boolean_t 1874 spa_writeable(spa_t *spa) 1875 { 1876 return (!!(spa->spa_mode & FWRITE)); 1877 } 1878 1879 /* 1880 * Returns true if there is a pending sync task in any of the current 1881 * syncing txg, the current quiescing txg, or the current open txg. 1882 */ 1883 boolean_t 1884 spa_has_pending_synctask(spa_t *spa) 1885 { 1886 return (!txg_all_lists_empty(&spa->spa_dsl_pool->dp_sync_tasks)); 1887 } 1888 1889 int 1890 spa_mode(spa_t *spa) 1891 { 1892 return (spa->spa_mode); 1893 } 1894 1895 uint64_t 1896 spa_bootfs(spa_t *spa) 1897 { 1898 return (spa->spa_bootfs); 1899 } 1900 1901 uint64_t 1902 spa_delegation(spa_t *spa) 1903 { 1904 return (spa->spa_delegation); 1905 } 1906 1907 objset_t * 1908 spa_meta_objset(spa_t *spa) 1909 { 1910 return (spa->spa_meta_objset); 1911 } 1912 1913 enum zio_checksum 1914 spa_dedup_checksum(spa_t *spa) 1915 { 1916 return (spa->spa_dedup_checksum); 1917 } 1918 1919 /* 1920 * Reset pool scan stat per scan pass (or reboot). 1921 */ 1922 void 1923 spa_scan_stat_init(spa_t *spa) 1924 { 1925 /* data not stored on disk */ 1926 spa->spa_scan_pass_start = gethrestime_sec(); 1927 spa->spa_scan_pass_exam = 0; 1928 vdev_scan_stat_init(spa->spa_root_vdev); 1929 } 1930 1931 /* 1932 * Get scan stats for zpool status reports 1933 */ 1934 int 1935 spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps) 1936 { 1937 dsl_scan_t *scn = spa->spa_dsl_pool ? spa->spa_dsl_pool->dp_scan : NULL; 1938 1939 if (scn == NULL || scn->scn_phys.scn_func == POOL_SCAN_NONE) 1940 return (SET_ERROR(ENOENT)); 1941 bzero(ps, sizeof (pool_scan_stat_t)); 1942 1943 /* data stored on disk */ 1944 ps->pss_func = scn->scn_phys.scn_func; 1945 ps->pss_start_time = scn->scn_phys.scn_start_time; 1946 ps->pss_end_time = scn->scn_phys.scn_end_time; 1947 ps->pss_to_examine = scn->scn_phys.scn_to_examine; 1948 ps->pss_examined = scn->scn_phys.scn_examined; 1949 ps->pss_to_process = scn->scn_phys.scn_to_process; 1950 ps->pss_processed = scn->scn_phys.scn_processed; 1951 ps->pss_errors = scn->scn_phys.scn_errors; 1952 ps->pss_state = scn->scn_phys.scn_state; 1953 1954 /* data not stored on disk */ 1955 ps->pss_pass_start = spa->spa_scan_pass_start; 1956 ps->pss_pass_exam = spa->spa_scan_pass_exam; 1957 1958 return (0); 1959 } 1960 1961 boolean_t 1962 spa_debug_enabled(spa_t *spa) 1963 { 1964 return (spa->spa_debug); 1965 } 1966 1967 int 1968 spa_maxblocksize(spa_t *spa) 1969 { 1970 if (spa_feature_is_enabled(spa, SPA_FEATURE_LARGE_BLOCKS)) 1971 return (SPA_MAXBLOCKSIZE); 1972 else 1973 return (SPA_OLD_MAXBLOCKSIZE); 1974 } 1975