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, 2017 by Delphix. All rights reserved. 24 * Copyright 2015 Nexenta Systems, Inc. All rights reserved. 25 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 26 * Copyright 2013 Saso Kiselkov. All rights reserved. 27 * Copyright (c) 2014 Integros [integros.com] 28 */ 29 30 #include <sys/zfs_context.h> 31 #include <sys/spa_impl.h> 32 #include <sys/spa_boot.h> 33 #include <sys/zio.h> 34 #include <sys/zio_checksum.h> 35 #include <sys/zio_compress.h> 36 #include <sys/dmu.h> 37 #include <sys/dmu_tx.h> 38 #include <sys/zap.h> 39 #include <sys/zil.h> 40 #include <sys/vdev_impl.h> 41 #include <sys/metaslab.h> 42 #include <sys/uberblock_impl.h> 43 #include <sys/txg.h> 44 #include <sys/avl.h> 45 #include <sys/unique.h> 46 #include <sys/dsl_pool.h> 47 #include <sys/dsl_dir.h> 48 #include <sys/dsl_prop.h> 49 #include <sys/dsl_scan.h> 50 #include <sys/fs/zfs.h> 51 #include <sys/metaslab_impl.h> 52 #include <sys/arc.h> 53 #include <sys/ddt.h> 54 #include "zfs_prop.h" 55 #include <sys/zfeature.h> 56 57 /* 58 * SPA locking 59 * 60 * There are four basic locks for managing spa_t structures: 61 * 62 * spa_namespace_lock (global mutex) 63 * 64 * This lock must be acquired to do any of the following: 65 * 66 * - Lookup a spa_t by name 67 * - Add or remove a spa_t from the namespace 68 * - Increase spa_refcount from non-zero 69 * - Check if spa_refcount is zero 70 * - Rename a spa_t 71 * - add/remove/attach/detach devices 72 * - Held for the duration of create/destroy/import/export 73 * 74 * It does not need to handle recursion. A create or destroy may 75 * reference objects (files or zvols) in other pools, but by 76 * definition they must have an existing reference, and will never need 77 * to lookup a spa_t by name. 78 * 79 * spa_refcount (per-spa refcount_t protected by mutex) 80 * 81 * This reference count keep track of any active users of the spa_t. The 82 * spa_t cannot be destroyed or freed while this is non-zero. Internally, 83 * the refcount is never really 'zero' - opening a pool implicitly keeps 84 * some references in the DMU. Internally we check against spa_minref, but 85 * present the image of a zero/non-zero value to consumers. 86 * 87 * spa_config_lock[] (per-spa array of rwlocks) 88 * 89 * This protects the spa_t from config changes, and must be held in 90 * the following circumstances: 91 * 92 * - RW_READER to perform I/O to the spa 93 * - RW_WRITER to change the vdev config 94 * 95 * The locking order is fairly straightforward: 96 * 97 * spa_namespace_lock -> spa_refcount 98 * 99 * The namespace lock must be acquired to increase the refcount from 0 100 * or to check if it is zero. 101 * 102 * spa_refcount -> spa_config_lock[] 103 * 104 * There must be at least one valid reference on the spa_t to acquire 105 * the config lock. 106 * 107 * spa_namespace_lock -> spa_config_lock[] 108 * 109 * The namespace lock must always be taken before the config lock. 110 * 111 * 112 * The spa_namespace_lock can be acquired directly and is globally visible. 113 * 114 * The namespace is manipulated using the following functions, all of which 115 * require the spa_namespace_lock to be held. 116 * 117 * spa_lookup() Lookup a spa_t by name. 118 * 119 * spa_add() Create a new spa_t in the namespace. 120 * 121 * spa_remove() Remove a spa_t from the namespace. This also 122 * frees up any memory associated with the spa_t. 123 * 124 * spa_next() Returns the next spa_t in the system, or the 125 * first if NULL is passed. 126 * 127 * spa_evict_all() Shutdown and remove all spa_t structures in 128 * the system. 129 * 130 * spa_guid_exists() Determine whether a pool/device guid exists. 131 * 132 * The spa_refcount is manipulated using the following functions: 133 * 134 * spa_open_ref() Adds a reference to the given spa_t. Must be 135 * called with spa_namespace_lock held if the 136 * refcount is currently zero. 137 * 138 * spa_close() Remove a reference from the spa_t. This will 139 * not free the spa_t or remove it from the 140 * namespace. No locking is required. 141 * 142 * spa_refcount_zero() Returns true if the refcount is currently 143 * zero. Must be called with spa_namespace_lock 144 * held. 145 * 146 * The spa_config_lock[] is an array of rwlocks, ordered as follows: 147 * SCL_CONFIG > SCL_STATE > SCL_ALLOC > SCL_ZIO > SCL_FREE > SCL_VDEV. 148 * spa_config_lock[] is manipulated with spa_config_{enter,exit,held}(). 149 * 150 * To read the configuration, it suffices to hold one of these locks as reader. 151 * To modify the configuration, you must hold all locks as writer. To modify 152 * vdev state without altering the vdev tree's topology (e.g. online/offline), 153 * you must hold SCL_STATE and SCL_ZIO as writer. 154 * 155 * We use these distinct config locks to avoid recursive lock entry. 156 * For example, spa_sync() (which holds SCL_CONFIG as reader) induces 157 * block allocations (SCL_ALLOC), which may require reading space maps 158 * from disk (dmu_read() -> zio_read() -> SCL_ZIO). 159 * 160 * The spa config locks cannot be normal rwlocks because we need the 161 * ability to hand off ownership. For example, SCL_ZIO is acquired 162 * by the issuing thread and later released by an interrupt thread. 163 * They do, however, obey the usual write-wanted semantics to prevent 164 * writer (i.e. system administrator) starvation. 165 * 166 * The lock acquisition rules are as follows: 167 * 168 * SCL_CONFIG 169 * Protects changes to the vdev tree topology, such as vdev 170 * add/remove/attach/detach. Protects the dirty config list 171 * (spa_config_dirty_list) and the set of spares and l2arc devices. 172 * 173 * SCL_STATE 174 * Protects changes to pool state and vdev state, such as vdev 175 * online/offline/fault/degrade/clear. Protects the dirty state list 176 * (spa_state_dirty_list) and global pool state (spa_state). 177 * 178 * SCL_ALLOC 179 * Protects changes to metaslab groups and classes. 180 * Held as reader by metaslab_alloc() and metaslab_claim(). 181 * 182 * SCL_ZIO 183 * Held by bp-level zios (those which have no io_vd upon entry) 184 * to prevent changes to the vdev tree. The bp-level zio implicitly 185 * protects all of its vdev child zios, which do not hold SCL_ZIO. 186 * 187 * SCL_FREE 188 * Protects changes to metaslab groups and classes. 189 * Held as reader by metaslab_free(). SCL_FREE is distinct from 190 * SCL_ALLOC, and lower than SCL_ZIO, so that we can safely free 191 * blocks in zio_done() while another i/o that holds either 192 * SCL_ALLOC or SCL_ZIO is waiting for this i/o to complete. 193 * 194 * SCL_VDEV 195 * Held as reader to prevent changes to the vdev tree during trivial 196 * inquiries such as bp_get_dsize(). SCL_VDEV is distinct from the 197 * other locks, and lower than all of them, to ensure that it's safe 198 * to acquire regardless of caller context. 199 * 200 * In addition, the following rules apply: 201 * 202 * (a) spa_props_lock protects pool properties, spa_config and spa_config_list. 203 * The lock ordering is SCL_CONFIG > spa_props_lock. 204 * 205 * (b) I/O operations on leaf vdevs. For any zio operation that takes 206 * an explicit vdev_t argument -- such as zio_ioctl(), zio_read_phys(), 207 * or zio_write_phys() -- the caller must ensure that the config cannot 208 * cannot change in the interim, and that the vdev cannot be reopened. 209 * SCL_STATE as reader suffices for both. 210 * 211 * The vdev configuration is protected by spa_vdev_enter() / spa_vdev_exit(). 212 * 213 * spa_vdev_enter() Acquire the namespace lock and the config lock 214 * for writing. 215 * 216 * spa_vdev_exit() Release the config lock, wait for all I/O 217 * to complete, sync the updated configs to the 218 * cache, and release the namespace lock. 219 * 220 * vdev state is protected by spa_vdev_state_enter() / spa_vdev_state_exit(). 221 * Like spa_vdev_enter/exit, these are convenience wrappers -- the actual 222 * locking is, always, based on spa_namespace_lock and spa_config_lock[]. 223 * 224 * spa_rename() is also implemented within this file since it requires 225 * manipulation of the namespace. 226 */ 227 228 static avl_tree_t spa_namespace_avl; 229 kmutex_t spa_namespace_lock; 230 static kcondvar_t spa_namespace_cv; 231 static int spa_active_count; 232 int spa_max_replication_override = SPA_DVAS_PER_BP; 233 234 static kmutex_t spa_spare_lock; 235 static avl_tree_t spa_spare_avl; 236 static kmutex_t spa_l2cache_lock; 237 static avl_tree_t spa_l2cache_avl; 238 239 kmem_cache_t *spa_buffer_pool; 240 int spa_mode_global; 241 242 #ifdef ZFS_DEBUG 243 /* Everything except dprintf and spa is on by default in debug builds */ 244 int zfs_flags = ~(ZFS_DEBUG_DPRINTF | ZFS_DEBUG_SPA); 245 #else 246 int zfs_flags = 0; 247 #endif 248 249 /* 250 * zfs_recover can be set to nonzero to attempt to recover from 251 * otherwise-fatal errors, typically caused by on-disk corruption. When 252 * set, calls to zfs_panic_recover() will turn into warning messages. 253 * This should only be used as a last resort, as it typically results 254 * in leaked space, or worse. 255 */ 256 boolean_t zfs_recover = B_FALSE; 257 258 /* 259 * If destroy encounters an EIO while reading metadata (e.g. indirect 260 * blocks), space referenced by the missing metadata can not be freed. 261 * Normally this causes the background destroy to become "stalled", as 262 * it is unable to make forward progress. While in this stalled state, 263 * all remaining space to free from the error-encountering filesystem is 264 * "temporarily leaked". Set this flag to cause it to ignore the EIO, 265 * permanently leak the space from indirect blocks that can not be read, 266 * and continue to free everything else that it can. 267 * 268 * The default, "stalling" behavior is useful if the storage partially 269 * fails (i.e. some but not all i/os fail), and then later recovers. In 270 * this case, we will be able to continue pool operations while it is 271 * partially failed, and when it recovers, we can continue to free the 272 * space, with no leaks. However, note that this case is actually 273 * fairly rare. 274 * 275 * Typically pools either (a) fail completely (but perhaps temporarily, 276 * e.g. a top-level vdev going offline), or (b) have localized, 277 * permanent errors (e.g. disk returns the wrong data due to bit flip or 278 * firmware bug). In case (a), this setting does not matter because the 279 * pool will be suspended and the sync thread will not be able to make 280 * forward progress regardless. In case (b), because the error is 281 * permanent, the best we can do is leak the minimum amount of space, 282 * which is what setting this flag will do. Therefore, it is reasonable 283 * for this flag to normally be set, but we chose the more conservative 284 * approach of not setting it, so that there is no possibility of 285 * leaking space in the "partial temporary" failure case. 286 */ 287 boolean_t zfs_free_leak_on_eio = B_FALSE; 288 289 /* 290 * Expiration time in milliseconds. This value has two meanings. First it is 291 * used to determine when the spa_deadman() logic should fire. By default the 292 * spa_deadman() will fire if spa_sync() has not completed in 1000 seconds. 293 * Secondly, the value determines if an I/O is considered "hung". Any I/O that 294 * has not completed in zfs_deadman_synctime_ms is considered "hung" resulting 295 * in a system panic. 296 */ 297 uint64_t zfs_deadman_synctime_ms = 1000000ULL; 298 299 /* 300 * Check time in milliseconds. This defines the frequency at which we check 301 * for hung I/O. 302 */ 303 uint64_t zfs_deadman_checktime_ms = 5000ULL; 304 305 /* 306 * Override the zfs deadman behavior via /etc/system. By default the 307 * deadman is enabled except on VMware and sparc deployments. 308 */ 309 int zfs_deadman_enabled = -1; 310 311 /* 312 * The worst case is single-sector max-parity RAID-Z blocks, in which 313 * case the space requirement is exactly (VDEV_RAIDZ_MAXPARITY + 1) 314 * times the size; so just assume that. Add to this the fact that 315 * we can have up to 3 DVAs per bp, and one more factor of 2 because 316 * the block may be dittoed with up to 3 DVAs by ddt_sync(). All together, 317 * the worst case is: 318 * (VDEV_RAIDZ_MAXPARITY + 1) * SPA_DVAS_PER_BP * 2 == 24 319 */ 320 int spa_asize_inflation = 24; 321 322 /* 323 * Normally, we don't allow the last 3.2% (1/(2^spa_slop_shift)) of space in 324 * the pool to be consumed. This ensures that we don't run the pool 325 * completely out of space, due to unaccounted changes (e.g. to the MOS). 326 * It also limits the worst-case time to allocate space. If we have 327 * less than this amount of free space, most ZPL operations (e.g. write, 328 * create) will return ENOSPC. 329 * 330 * Certain operations (e.g. file removal, most administrative actions) can 331 * use half the slop space. They will only return ENOSPC if less than half 332 * the slop space is free. Typically, once the pool has less than the slop 333 * space free, the user will use these operations to free up space in the pool. 334 * These are the operations that call dsl_pool_adjustedsize() with the netfree 335 * argument set to TRUE. 336 * 337 * A very restricted set of operations are always permitted, regardless of 338 * the amount of free space. These are the operations that call 339 * dsl_sync_task(ZFS_SPACE_CHECK_NONE), e.g. "zfs destroy". If these 340 * operations result in a net increase in the amount of space used, 341 * it is possible to run the pool completely out of space, causing it to 342 * be permanently read-only. 343 * 344 * Note that on very small pools, the slop space will be larger than 345 * 3.2%, in an effort to have it be at least spa_min_slop (128MB), 346 * but we never allow it to be more than half the pool size. 347 * 348 * See also the comments in zfs_space_check_t. 349 */ 350 int spa_slop_shift = 5; 351 uint64_t spa_min_slop = 128 * 1024 * 1024; 352 353 /* 354 * ========================================================================== 355 * SPA config locking 356 * ========================================================================== 357 */ 358 static void 359 spa_config_lock_init(spa_t *spa) 360 { 361 for (int i = 0; i < SCL_LOCKS; i++) { 362 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 363 mutex_init(&scl->scl_lock, NULL, MUTEX_DEFAULT, NULL); 364 cv_init(&scl->scl_cv, NULL, CV_DEFAULT, NULL); 365 refcount_create_untracked(&scl->scl_count); 366 scl->scl_writer = NULL; 367 scl->scl_write_wanted = 0; 368 } 369 } 370 371 static void 372 spa_config_lock_destroy(spa_t *spa) 373 { 374 for (int i = 0; i < SCL_LOCKS; i++) { 375 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 376 mutex_destroy(&scl->scl_lock); 377 cv_destroy(&scl->scl_cv); 378 refcount_destroy(&scl->scl_count); 379 ASSERT(scl->scl_writer == NULL); 380 ASSERT(scl->scl_write_wanted == 0); 381 } 382 } 383 384 int 385 spa_config_tryenter(spa_t *spa, int locks, void *tag, krw_t rw) 386 { 387 for (int i = 0; i < SCL_LOCKS; i++) { 388 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 389 if (!(locks & (1 << i))) 390 continue; 391 mutex_enter(&scl->scl_lock); 392 if (rw == RW_READER) { 393 if (scl->scl_writer || scl->scl_write_wanted) { 394 mutex_exit(&scl->scl_lock); 395 spa_config_exit(spa, locks & ((1 << i) - 1), 396 tag); 397 return (0); 398 } 399 } else { 400 ASSERT(scl->scl_writer != curthread); 401 if (!refcount_is_zero(&scl->scl_count)) { 402 mutex_exit(&scl->scl_lock); 403 spa_config_exit(spa, locks & ((1 << i) - 1), 404 tag); 405 return (0); 406 } 407 scl->scl_writer = curthread; 408 } 409 (void) refcount_add(&scl->scl_count, tag); 410 mutex_exit(&scl->scl_lock); 411 } 412 return (1); 413 } 414 415 void 416 spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw) 417 { 418 int wlocks_held = 0; 419 420 ASSERT3U(SCL_LOCKS, <, sizeof (wlocks_held) * NBBY); 421 422 for (int i = 0; i < SCL_LOCKS; i++) { 423 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 424 if (scl->scl_writer == curthread) 425 wlocks_held |= (1 << i); 426 if (!(locks & (1 << i))) 427 continue; 428 mutex_enter(&scl->scl_lock); 429 if (rw == RW_READER) { 430 while (scl->scl_writer || scl->scl_write_wanted) { 431 cv_wait(&scl->scl_cv, &scl->scl_lock); 432 } 433 } else { 434 ASSERT(scl->scl_writer != curthread); 435 while (!refcount_is_zero(&scl->scl_count)) { 436 scl->scl_write_wanted++; 437 cv_wait(&scl->scl_cv, &scl->scl_lock); 438 scl->scl_write_wanted--; 439 } 440 scl->scl_writer = curthread; 441 } 442 (void) refcount_add(&scl->scl_count, tag); 443 mutex_exit(&scl->scl_lock); 444 } 445 ASSERT(wlocks_held <= locks); 446 } 447 448 void 449 spa_config_exit(spa_t *spa, int locks, void *tag) 450 { 451 for (int i = SCL_LOCKS - 1; i >= 0; i--) { 452 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 453 if (!(locks & (1 << i))) 454 continue; 455 mutex_enter(&scl->scl_lock); 456 ASSERT(!refcount_is_zero(&scl->scl_count)); 457 if (refcount_remove(&scl->scl_count, tag) == 0) { 458 ASSERT(scl->scl_writer == NULL || 459 scl->scl_writer == curthread); 460 scl->scl_writer = NULL; /* OK in either case */ 461 cv_broadcast(&scl->scl_cv); 462 } 463 mutex_exit(&scl->scl_lock); 464 } 465 } 466 467 int 468 spa_config_held(spa_t *spa, int locks, krw_t rw) 469 { 470 int locks_held = 0; 471 472 for (int i = 0; i < SCL_LOCKS; i++) { 473 spa_config_lock_t *scl = &spa->spa_config_lock[i]; 474 if (!(locks & (1 << i))) 475 continue; 476 if ((rw == RW_READER && !refcount_is_zero(&scl->scl_count)) || 477 (rw == RW_WRITER && scl->scl_writer == curthread)) 478 locks_held |= 1 << i; 479 } 480 481 return (locks_held); 482 } 483 484 /* 485 * ========================================================================== 486 * SPA namespace functions 487 * ========================================================================== 488 */ 489 490 /* 491 * Lookup the named spa_t in the AVL tree. The spa_namespace_lock must be held. 492 * Returns NULL if no matching spa_t is found. 493 */ 494 spa_t * 495 spa_lookup(const char *name) 496 { 497 static spa_t search; /* spa_t is large; don't allocate on stack */ 498 spa_t *spa; 499 avl_index_t where; 500 char *cp; 501 502 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 503 504 (void) strlcpy(search.spa_name, name, sizeof (search.spa_name)); 505 506 /* 507 * If it's a full dataset name, figure out the pool name and 508 * just use that. 509 */ 510 cp = strpbrk(search.spa_name, "/@#"); 511 if (cp != NULL) 512 *cp = '\0'; 513 514 spa = avl_find(&spa_namespace_avl, &search, &where); 515 516 return (spa); 517 } 518 519 /* 520 * Fires when spa_sync has not completed within zfs_deadman_synctime_ms. 521 * If the zfs_deadman_enabled flag is set then it inspects all vdev queues 522 * looking for potentially hung I/Os. 523 */ 524 void 525 spa_deadman(void *arg) 526 { 527 spa_t *spa = arg; 528 529 /* 530 * Disable the deadman timer if the pool is suspended. 531 */ 532 if (spa_suspended(spa)) { 533 VERIFY(cyclic_reprogram(spa->spa_deadman_cycid, CY_INFINITY)); 534 return; 535 } 536 537 zfs_dbgmsg("slow spa_sync: started %llu seconds ago, calls %llu", 538 (gethrtime() - spa->spa_sync_starttime) / NANOSEC, 539 ++spa->spa_deadman_calls); 540 if (zfs_deadman_enabled) 541 vdev_deadman(spa->spa_root_vdev); 542 } 543 544 /* 545 * Create an uninitialized spa_t with the given name. Requires 546 * spa_namespace_lock. The caller must ensure that the spa_t doesn't already 547 * exist by calling spa_lookup() first. 548 */ 549 spa_t * 550 spa_add(const char *name, nvlist_t *config, const char *altroot) 551 { 552 spa_t *spa; 553 spa_config_dirent_t *dp; 554 cyc_handler_t hdlr; 555 cyc_time_t when; 556 557 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 558 559 spa = kmem_zalloc(sizeof (spa_t), KM_SLEEP); 560 561 mutex_init(&spa->spa_async_lock, NULL, MUTEX_DEFAULT, NULL); 562 mutex_init(&spa->spa_errlist_lock, NULL, MUTEX_DEFAULT, NULL); 563 mutex_init(&spa->spa_errlog_lock, NULL, MUTEX_DEFAULT, NULL); 564 mutex_init(&spa->spa_evicting_os_lock, NULL, MUTEX_DEFAULT, NULL); 565 mutex_init(&spa->spa_history_lock, NULL, MUTEX_DEFAULT, NULL); 566 mutex_init(&spa->spa_proc_lock, NULL, MUTEX_DEFAULT, NULL); 567 mutex_init(&spa->spa_props_lock, NULL, MUTEX_DEFAULT, NULL); 568 mutex_init(&spa->spa_cksum_tmpls_lock, NULL, MUTEX_DEFAULT, NULL); 569 mutex_init(&spa->spa_scrub_lock, NULL, MUTEX_DEFAULT, NULL); 570 mutex_init(&spa->spa_suspend_lock, NULL, MUTEX_DEFAULT, NULL); 571 mutex_init(&spa->spa_vdev_top_lock, NULL, MUTEX_DEFAULT, NULL); 572 mutex_init(&spa->spa_iokstat_lock, NULL, MUTEX_DEFAULT, NULL); 573 mutex_init(&spa->spa_alloc_lock, NULL, MUTEX_DEFAULT, NULL); 574 575 cv_init(&spa->spa_async_cv, NULL, CV_DEFAULT, NULL); 576 cv_init(&spa->spa_evicting_os_cv, NULL, CV_DEFAULT, NULL); 577 cv_init(&spa->spa_proc_cv, NULL, CV_DEFAULT, NULL); 578 cv_init(&spa->spa_scrub_io_cv, NULL, CV_DEFAULT, NULL); 579 cv_init(&spa->spa_suspend_cv, NULL, CV_DEFAULT, NULL); 580 581 for (int t = 0; t < TXG_SIZE; t++) 582 bplist_create(&spa->spa_free_bplist[t]); 583 584 (void) strlcpy(spa->spa_name, name, sizeof (spa->spa_name)); 585 spa->spa_state = POOL_STATE_UNINITIALIZED; 586 spa->spa_freeze_txg = UINT64_MAX; 587 spa->spa_final_txg = UINT64_MAX; 588 spa->spa_load_max_txg = UINT64_MAX; 589 spa->spa_proc = &p0; 590 spa->spa_proc_state = SPA_PROC_NONE; 591 592 hdlr.cyh_func = spa_deadman; 593 hdlr.cyh_arg = spa; 594 hdlr.cyh_level = CY_LOW_LEVEL; 595 596 spa->spa_deadman_synctime = MSEC2NSEC(zfs_deadman_synctime_ms); 597 598 /* 599 * This determines how often we need to check for hung I/Os after 600 * the cyclic has already fired. Since checking for hung I/Os is 601 * an expensive operation we don't want to check too frequently. 602 * Instead wait for 5 seconds before checking again. 603 */ 604 when.cyt_interval = MSEC2NSEC(zfs_deadman_checktime_ms); 605 when.cyt_when = CY_INFINITY; 606 mutex_enter(&cpu_lock); 607 spa->spa_deadman_cycid = cyclic_add(&hdlr, &when); 608 mutex_exit(&cpu_lock); 609 610 refcount_create(&spa->spa_refcount); 611 spa_config_lock_init(spa); 612 613 avl_add(&spa_namespace_avl, spa); 614 615 /* 616 * Set the alternate root, if there is one. 617 */ 618 if (altroot) { 619 spa->spa_root = spa_strdup(altroot); 620 spa_active_count++; 621 } 622 623 avl_create(&spa->spa_alloc_tree, zio_bookmark_compare, 624 sizeof (zio_t), offsetof(zio_t, io_alloc_node)); 625 626 /* 627 * Every pool starts with the default cachefile 628 */ 629 list_create(&spa->spa_config_list, sizeof (spa_config_dirent_t), 630 offsetof(spa_config_dirent_t, scd_link)); 631 632 dp = kmem_zalloc(sizeof (spa_config_dirent_t), KM_SLEEP); 633 dp->scd_path = altroot ? NULL : spa_strdup(spa_config_path); 634 list_insert_head(&spa->spa_config_list, dp); 635 636 VERIFY(nvlist_alloc(&spa->spa_load_info, NV_UNIQUE_NAME, 637 KM_SLEEP) == 0); 638 639 if (config != NULL) { 640 nvlist_t *features; 641 642 if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ, 643 &features) == 0) { 644 VERIFY(nvlist_dup(features, &spa->spa_label_features, 645 0) == 0); 646 } 647 648 VERIFY(nvlist_dup(config, &spa->spa_config, 0) == 0); 649 } 650 651 if (spa->spa_label_features == NULL) { 652 VERIFY(nvlist_alloc(&spa->spa_label_features, NV_UNIQUE_NAME, 653 KM_SLEEP) == 0); 654 } 655 656 spa->spa_iokstat = kstat_create("zfs", 0, name, 657 "disk", KSTAT_TYPE_IO, 1, 0); 658 if (spa->spa_iokstat) { 659 spa->spa_iokstat->ks_lock = &spa->spa_iokstat_lock; 660 kstat_install(spa->spa_iokstat); 661 } 662 663 spa->spa_debug = ((zfs_flags & ZFS_DEBUG_SPA) != 0); 664 665 spa->spa_min_ashift = INT_MAX; 666 spa->spa_max_ashift = 0; 667 668 /* 669 * As a pool is being created, treat all features as disabled by 670 * setting SPA_FEATURE_DISABLED for all entries in the feature 671 * refcount cache. 672 */ 673 for (int i = 0; i < SPA_FEATURES; i++) { 674 spa->spa_feat_refcount_cache[i] = SPA_FEATURE_DISABLED; 675 } 676 677 return (spa); 678 } 679 680 /* 681 * Removes a spa_t from the namespace, freeing up any memory used. Requires 682 * spa_namespace_lock. This is called only after the spa_t has been closed and 683 * deactivated. 684 */ 685 void 686 spa_remove(spa_t *spa) 687 { 688 spa_config_dirent_t *dp; 689 690 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 691 ASSERT(spa->spa_state == POOL_STATE_UNINITIALIZED); 692 ASSERT3U(refcount_count(&spa->spa_refcount), ==, 0); 693 694 nvlist_free(spa->spa_config_splitting); 695 696 avl_remove(&spa_namespace_avl, spa); 697 cv_broadcast(&spa_namespace_cv); 698 699 if (spa->spa_root) { 700 spa_strfree(spa->spa_root); 701 spa_active_count--; 702 } 703 704 while ((dp = list_head(&spa->spa_config_list)) != NULL) { 705 list_remove(&spa->spa_config_list, dp); 706 if (dp->scd_path != NULL) 707 spa_strfree(dp->scd_path); 708 kmem_free(dp, sizeof (spa_config_dirent_t)); 709 } 710 711 avl_destroy(&spa->spa_alloc_tree); 712 list_destroy(&spa->spa_config_list); 713 714 nvlist_free(spa->spa_label_features); 715 nvlist_free(spa->spa_load_info); 716 spa_config_set(spa, NULL); 717 718 mutex_enter(&cpu_lock); 719 if (spa->spa_deadman_cycid != CYCLIC_NONE) 720 cyclic_remove(spa->spa_deadman_cycid); 721 mutex_exit(&cpu_lock); 722 spa->spa_deadman_cycid = CYCLIC_NONE; 723 724 refcount_destroy(&spa->spa_refcount); 725 726 spa_config_lock_destroy(spa); 727 728 kstat_delete(spa->spa_iokstat); 729 spa->spa_iokstat = NULL; 730 731 for (int t = 0; t < TXG_SIZE; t++) 732 bplist_destroy(&spa->spa_free_bplist[t]); 733 734 zio_checksum_templates_free(spa); 735 736 cv_destroy(&spa->spa_async_cv); 737 cv_destroy(&spa->spa_evicting_os_cv); 738 cv_destroy(&spa->spa_proc_cv); 739 cv_destroy(&spa->spa_scrub_io_cv); 740 cv_destroy(&spa->spa_suspend_cv); 741 742 mutex_destroy(&spa->spa_alloc_lock); 743 mutex_destroy(&spa->spa_async_lock); 744 mutex_destroy(&spa->spa_errlist_lock); 745 mutex_destroy(&spa->spa_errlog_lock); 746 mutex_destroy(&spa->spa_evicting_os_lock); 747 mutex_destroy(&spa->spa_history_lock); 748 mutex_destroy(&spa->spa_proc_lock); 749 mutex_destroy(&spa->spa_props_lock); 750 mutex_destroy(&spa->spa_cksum_tmpls_lock); 751 mutex_destroy(&spa->spa_scrub_lock); 752 mutex_destroy(&spa->spa_suspend_lock); 753 mutex_destroy(&spa->spa_vdev_top_lock); 754 mutex_destroy(&spa->spa_iokstat_lock); 755 756 kmem_free(spa, sizeof (spa_t)); 757 } 758 759 /* 760 * Given a pool, return the next pool in the namespace, or NULL if there is 761 * none. If 'prev' is NULL, return the first pool. 762 */ 763 spa_t * 764 spa_next(spa_t *prev) 765 { 766 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 767 768 if (prev) 769 return (AVL_NEXT(&spa_namespace_avl, prev)); 770 else 771 return (avl_first(&spa_namespace_avl)); 772 } 773 774 /* 775 * ========================================================================== 776 * SPA refcount functions 777 * ========================================================================== 778 */ 779 780 /* 781 * Add a reference to the given spa_t. Must have at least one reference, or 782 * have the namespace lock held. 783 */ 784 void 785 spa_open_ref(spa_t *spa, void *tag) 786 { 787 ASSERT(refcount_count(&spa->spa_refcount) >= spa->spa_minref || 788 MUTEX_HELD(&spa_namespace_lock)); 789 (void) refcount_add(&spa->spa_refcount, tag); 790 } 791 792 /* 793 * Remove a reference to the given spa_t. Must have at least one reference, or 794 * have the namespace lock held. 795 */ 796 void 797 spa_close(spa_t *spa, void *tag) 798 { 799 ASSERT(refcount_count(&spa->spa_refcount) > spa->spa_minref || 800 MUTEX_HELD(&spa_namespace_lock)); 801 (void) refcount_remove(&spa->spa_refcount, tag); 802 } 803 804 /* 805 * Remove a reference to the given spa_t held by a dsl dir that is 806 * being asynchronously released. Async releases occur from a taskq 807 * performing eviction of dsl datasets and dirs. The namespace lock 808 * isn't held and the hold by the object being evicted may contribute to 809 * spa_minref (e.g. dataset or directory released during pool export), 810 * so the asserts in spa_close() do not apply. 811 */ 812 void 813 spa_async_close(spa_t *spa, void *tag) 814 { 815 (void) refcount_remove(&spa->spa_refcount, tag); 816 } 817 818 /* 819 * Check to see if the spa refcount is zero. Must be called with 820 * spa_namespace_lock held. We really compare against spa_minref, which is the 821 * number of references acquired when opening a pool 822 */ 823 boolean_t 824 spa_refcount_zero(spa_t *spa) 825 { 826 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 827 828 return (refcount_count(&spa->spa_refcount) == spa->spa_minref); 829 } 830 831 /* 832 * ========================================================================== 833 * SPA spare and l2cache tracking 834 * ========================================================================== 835 */ 836 837 /* 838 * Hot spares and cache devices are tracked using the same code below, 839 * for 'auxiliary' devices. 840 */ 841 842 typedef struct spa_aux { 843 uint64_t aux_guid; 844 uint64_t aux_pool; 845 avl_node_t aux_avl; 846 int aux_count; 847 } spa_aux_t; 848 849 static int 850 spa_aux_compare(const void *a, const void *b) 851 { 852 const spa_aux_t *sa = a; 853 const spa_aux_t *sb = b; 854 855 if (sa->aux_guid < sb->aux_guid) 856 return (-1); 857 else if (sa->aux_guid > sb->aux_guid) 858 return (1); 859 else 860 return (0); 861 } 862 863 void 864 spa_aux_add(vdev_t *vd, avl_tree_t *avl) 865 { 866 avl_index_t where; 867 spa_aux_t search; 868 spa_aux_t *aux; 869 870 search.aux_guid = vd->vdev_guid; 871 if ((aux = avl_find(avl, &search, &where)) != NULL) { 872 aux->aux_count++; 873 } else { 874 aux = kmem_zalloc(sizeof (spa_aux_t), KM_SLEEP); 875 aux->aux_guid = vd->vdev_guid; 876 aux->aux_count = 1; 877 avl_insert(avl, aux, where); 878 } 879 } 880 881 void 882 spa_aux_remove(vdev_t *vd, avl_tree_t *avl) 883 { 884 spa_aux_t search; 885 spa_aux_t *aux; 886 avl_index_t where; 887 888 search.aux_guid = vd->vdev_guid; 889 aux = avl_find(avl, &search, &where); 890 891 ASSERT(aux != NULL); 892 893 if (--aux->aux_count == 0) { 894 avl_remove(avl, aux); 895 kmem_free(aux, sizeof (spa_aux_t)); 896 } else if (aux->aux_pool == spa_guid(vd->vdev_spa)) { 897 aux->aux_pool = 0ULL; 898 } 899 } 900 901 boolean_t 902 spa_aux_exists(uint64_t guid, uint64_t *pool, int *refcnt, avl_tree_t *avl) 903 { 904 spa_aux_t search, *found; 905 906 search.aux_guid = guid; 907 found = avl_find(avl, &search, NULL); 908 909 if (pool) { 910 if (found) 911 *pool = found->aux_pool; 912 else 913 *pool = 0ULL; 914 } 915 916 if (refcnt) { 917 if (found) 918 *refcnt = found->aux_count; 919 else 920 *refcnt = 0; 921 } 922 923 return (found != NULL); 924 } 925 926 void 927 spa_aux_activate(vdev_t *vd, avl_tree_t *avl) 928 { 929 spa_aux_t search, *found; 930 avl_index_t where; 931 932 search.aux_guid = vd->vdev_guid; 933 found = avl_find(avl, &search, &where); 934 ASSERT(found != NULL); 935 ASSERT(found->aux_pool == 0ULL); 936 937 found->aux_pool = spa_guid(vd->vdev_spa); 938 } 939 940 /* 941 * Spares are tracked globally due to the following constraints: 942 * 943 * - A spare may be part of multiple pools. 944 * - A spare may be added to a pool even if it's actively in use within 945 * another pool. 946 * - A spare in use in any pool can only be the source of a replacement if 947 * the target is a spare in the same pool. 948 * 949 * We keep track of all spares on the system through the use of a reference 950 * counted AVL tree. When a vdev is added as a spare, or used as a replacement 951 * spare, then we bump the reference count in the AVL tree. In addition, we set 952 * the 'vdev_isspare' member to indicate that the device is a spare (active or 953 * inactive). When a spare is made active (used to replace a device in the 954 * pool), we also keep track of which pool its been made a part of. 955 * 956 * The 'spa_spare_lock' protects the AVL tree. These functions are normally 957 * called under the spa_namespace lock as part of vdev reconfiguration. The 958 * separate spare lock exists for the status query path, which does not need to 959 * be completely consistent with respect to other vdev configuration changes. 960 */ 961 962 static int 963 spa_spare_compare(const void *a, const void *b) 964 { 965 return (spa_aux_compare(a, b)); 966 } 967 968 void 969 spa_spare_add(vdev_t *vd) 970 { 971 mutex_enter(&spa_spare_lock); 972 ASSERT(!vd->vdev_isspare); 973 spa_aux_add(vd, &spa_spare_avl); 974 vd->vdev_isspare = B_TRUE; 975 mutex_exit(&spa_spare_lock); 976 } 977 978 void 979 spa_spare_remove(vdev_t *vd) 980 { 981 mutex_enter(&spa_spare_lock); 982 ASSERT(vd->vdev_isspare); 983 spa_aux_remove(vd, &spa_spare_avl); 984 vd->vdev_isspare = B_FALSE; 985 mutex_exit(&spa_spare_lock); 986 } 987 988 boolean_t 989 spa_spare_exists(uint64_t guid, uint64_t *pool, int *refcnt) 990 { 991 boolean_t found; 992 993 mutex_enter(&spa_spare_lock); 994 found = spa_aux_exists(guid, pool, refcnt, &spa_spare_avl); 995 mutex_exit(&spa_spare_lock); 996 997 return (found); 998 } 999 1000 void 1001 spa_spare_activate(vdev_t *vd) 1002 { 1003 mutex_enter(&spa_spare_lock); 1004 ASSERT(vd->vdev_isspare); 1005 spa_aux_activate(vd, &spa_spare_avl); 1006 mutex_exit(&spa_spare_lock); 1007 } 1008 1009 /* 1010 * Level 2 ARC devices are tracked globally for the same reasons as spares. 1011 * Cache devices currently only support one pool per cache device, and so 1012 * for these devices the aux reference count is currently unused beyond 1. 1013 */ 1014 1015 static int 1016 spa_l2cache_compare(const void *a, const void *b) 1017 { 1018 return (spa_aux_compare(a, b)); 1019 } 1020 1021 void 1022 spa_l2cache_add(vdev_t *vd) 1023 { 1024 mutex_enter(&spa_l2cache_lock); 1025 ASSERT(!vd->vdev_isl2cache); 1026 spa_aux_add(vd, &spa_l2cache_avl); 1027 vd->vdev_isl2cache = B_TRUE; 1028 mutex_exit(&spa_l2cache_lock); 1029 } 1030 1031 void 1032 spa_l2cache_remove(vdev_t *vd) 1033 { 1034 mutex_enter(&spa_l2cache_lock); 1035 ASSERT(vd->vdev_isl2cache); 1036 spa_aux_remove(vd, &spa_l2cache_avl); 1037 vd->vdev_isl2cache = B_FALSE; 1038 mutex_exit(&spa_l2cache_lock); 1039 } 1040 1041 boolean_t 1042 spa_l2cache_exists(uint64_t guid, uint64_t *pool) 1043 { 1044 boolean_t found; 1045 1046 mutex_enter(&spa_l2cache_lock); 1047 found = spa_aux_exists(guid, pool, NULL, &spa_l2cache_avl); 1048 mutex_exit(&spa_l2cache_lock); 1049 1050 return (found); 1051 } 1052 1053 void 1054 spa_l2cache_activate(vdev_t *vd) 1055 { 1056 mutex_enter(&spa_l2cache_lock); 1057 ASSERT(vd->vdev_isl2cache); 1058 spa_aux_activate(vd, &spa_l2cache_avl); 1059 mutex_exit(&spa_l2cache_lock); 1060 } 1061 1062 /* 1063 * ========================================================================== 1064 * SPA vdev locking 1065 * ========================================================================== 1066 */ 1067 1068 /* 1069 * Lock the given spa_t for the purpose of adding or removing a vdev. 1070 * Grabs the global spa_namespace_lock plus the spa config lock for writing. 1071 * It returns the next transaction group for the spa_t. 1072 */ 1073 uint64_t 1074 spa_vdev_enter(spa_t *spa) 1075 { 1076 mutex_enter(&spa->spa_vdev_top_lock); 1077 mutex_enter(&spa_namespace_lock); 1078 return (spa_vdev_config_enter(spa)); 1079 } 1080 1081 /* 1082 * Internal implementation for spa_vdev_enter(). Used when a vdev 1083 * operation requires multiple syncs (i.e. removing a device) while 1084 * keeping the spa_namespace_lock held. 1085 */ 1086 uint64_t 1087 spa_vdev_config_enter(spa_t *spa) 1088 { 1089 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1090 1091 spa_config_enter(spa, SCL_ALL, spa, RW_WRITER); 1092 1093 return (spa_last_synced_txg(spa) + 1); 1094 } 1095 1096 /* 1097 * Used in combination with spa_vdev_config_enter() to allow the syncing 1098 * of multiple transactions without releasing the spa_namespace_lock. 1099 */ 1100 void 1101 spa_vdev_config_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error, char *tag) 1102 { 1103 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1104 1105 int config_changed = B_FALSE; 1106 1107 ASSERT(txg > spa_last_synced_txg(spa)); 1108 1109 spa->spa_pending_vdev = NULL; 1110 1111 /* 1112 * Reassess the DTLs. 1113 */ 1114 vdev_dtl_reassess(spa->spa_root_vdev, 0, 0, B_FALSE); 1115 1116 if (error == 0 && !list_is_empty(&spa->spa_config_dirty_list)) { 1117 config_changed = B_TRUE; 1118 spa->spa_config_generation++; 1119 } 1120 1121 /* 1122 * Verify the metaslab classes. 1123 */ 1124 ASSERT(metaslab_class_validate(spa_normal_class(spa)) == 0); 1125 ASSERT(metaslab_class_validate(spa_log_class(spa)) == 0); 1126 1127 spa_config_exit(spa, SCL_ALL, spa); 1128 1129 /* 1130 * Panic the system if the specified tag requires it. This 1131 * is useful for ensuring that configurations are updated 1132 * transactionally. 1133 */ 1134 if (zio_injection_enabled) 1135 zio_handle_panic_injection(spa, tag, 0); 1136 1137 /* 1138 * Note: this txg_wait_synced() is important because it ensures 1139 * that there won't be more than one config change per txg. 1140 * This allows us to use the txg as the generation number. 1141 */ 1142 if (error == 0) 1143 txg_wait_synced(spa->spa_dsl_pool, txg); 1144 1145 if (vd != NULL) { 1146 ASSERT(!vd->vdev_detached || vd->vdev_dtl_sm == NULL); 1147 spa_config_enter(spa, SCL_ALL, spa, RW_WRITER); 1148 vdev_free(vd); 1149 spa_config_exit(spa, SCL_ALL, spa); 1150 } 1151 1152 /* 1153 * If the config changed, update the config cache. 1154 */ 1155 if (config_changed) 1156 spa_config_sync(spa, B_FALSE, B_TRUE); 1157 } 1158 1159 /* 1160 * Unlock the spa_t after adding or removing a vdev. Besides undoing the 1161 * locking of spa_vdev_enter(), we also want make sure the transactions have 1162 * synced to disk, and then update the global configuration cache with the new 1163 * information. 1164 */ 1165 int 1166 spa_vdev_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error) 1167 { 1168 spa_vdev_config_exit(spa, vd, txg, error, FTAG); 1169 mutex_exit(&spa_namespace_lock); 1170 mutex_exit(&spa->spa_vdev_top_lock); 1171 1172 return (error); 1173 } 1174 1175 /* 1176 * Lock the given spa_t for the purpose of changing vdev state. 1177 */ 1178 void 1179 spa_vdev_state_enter(spa_t *spa, int oplocks) 1180 { 1181 int locks = SCL_STATE_ALL | oplocks; 1182 1183 /* 1184 * Root pools may need to read of the underlying devfs filesystem 1185 * when opening up a vdev. Unfortunately if we're holding the 1186 * SCL_ZIO lock it will result in a deadlock when we try to issue 1187 * the read from the root filesystem. Instead we "prefetch" 1188 * the associated vnodes that we need prior to opening the 1189 * underlying devices and cache them so that we can prevent 1190 * any I/O when we are doing the actual open. 1191 */ 1192 if (spa_is_root(spa)) { 1193 int low = locks & ~(SCL_ZIO - 1); 1194 int high = locks & ~low; 1195 1196 spa_config_enter(spa, high, spa, RW_WRITER); 1197 vdev_hold(spa->spa_root_vdev); 1198 spa_config_enter(spa, low, spa, RW_WRITER); 1199 } else { 1200 spa_config_enter(spa, locks, spa, RW_WRITER); 1201 } 1202 spa->spa_vdev_locks = locks; 1203 } 1204 1205 int 1206 spa_vdev_state_exit(spa_t *spa, vdev_t *vd, int error) 1207 { 1208 boolean_t config_changed = B_FALSE; 1209 1210 if (vd != NULL || error == 0) 1211 vdev_dtl_reassess(vd ? vd->vdev_top : spa->spa_root_vdev, 1212 0, 0, B_FALSE); 1213 1214 if (vd != NULL) { 1215 vdev_state_dirty(vd->vdev_top); 1216 config_changed = B_TRUE; 1217 spa->spa_config_generation++; 1218 } 1219 1220 if (spa_is_root(spa)) 1221 vdev_rele(spa->spa_root_vdev); 1222 1223 ASSERT3U(spa->spa_vdev_locks, >=, SCL_STATE_ALL); 1224 spa_config_exit(spa, spa->spa_vdev_locks, spa); 1225 1226 /* 1227 * If anything changed, wait for it to sync. This ensures that, 1228 * from the system administrator's perspective, zpool(1M) commands 1229 * are synchronous. This is important for things like zpool offline: 1230 * when the command completes, you expect no further I/O from ZFS. 1231 */ 1232 if (vd != NULL) 1233 txg_wait_synced(spa->spa_dsl_pool, 0); 1234 1235 /* 1236 * If the config changed, update the config cache. 1237 */ 1238 if (config_changed) { 1239 mutex_enter(&spa_namespace_lock); 1240 spa_config_sync(spa, B_FALSE, B_TRUE); 1241 mutex_exit(&spa_namespace_lock); 1242 } 1243 1244 return (error); 1245 } 1246 1247 /* 1248 * ========================================================================== 1249 * Miscellaneous functions 1250 * ========================================================================== 1251 */ 1252 1253 void 1254 spa_activate_mos_feature(spa_t *spa, const char *feature, dmu_tx_t *tx) 1255 { 1256 if (!nvlist_exists(spa->spa_label_features, feature)) { 1257 fnvlist_add_boolean(spa->spa_label_features, feature); 1258 /* 1259 * When we are creating the pool (tx_txg==TXG_INITIAL), we can't 1260 * dirty the vdev config because lock SCL_CONFIG is not held. 1261 * Thankfully, in this case we don't need to dirty the config 1262 * because it will be written out anyway when we finish 1263 * creating the pool. 1264 */ 1265 if (tx->tx_txg != TXG_INITIAL) 1266 vdev_config_dirty(spa->spa_root_vdev); 1267 } 1268 } 1269 1270 void 1271 spa_deactivate_mos_feature(spa_t *spa, const char *feature) 1272 { 1273 if (nvlist_remove_all(spa->spa_label_features, feature) == 0) 1274 vdev_config_dirty(spa->spa_root_vdev); 1275 } 1276 1277 /* 1278 * Rename a spa_t. 1279 */ 1280 int 1281 spa_rename(const char *name, const char *newname) 1282 { 1283 spa_t *spa; 1284 int err; 1285 1286 /* 1287 * Lookup the spa_t and grab the config lock for writing. We need to 1288 * actually open the pool so that we can sync out the necessary labels. 1289 * It's OK to call spa_open() with the namespace lock held because we 1290 * allow recursive calls for other reasons. 1291 */ 1292 mutex_enter(&spa_namespace_lock); 1293 if ((err = spa_open(name, &spa, FTAG)) != 0) { 1294 mutex_exit(&spa_namespace_lock); 1295 return (err); 1296 } 1297 1298 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1299 1300 avl_remove(&spa_namespace_avl, spa); 1301 (void) strlcpy(spa->spa_name, newname, sizeof (spa->spa_name)); 1302 avl_add(&spa_namespace_avl, spa); 1303 1304 /* 1305 * Sync all labels to disk with the new names by marking the root vdev 1306 * dirty and waiting for it to sync. It will pick up the new pool name 1307 * during the sync. 1308 */ 1309 vdev_config_dirty(spa->spa_root_vdev); 1310 1311 spa_config_exit(spa, SCL_ALL, FTAG); 1312 1313 txg_wait_synced(spa->spa_dsl_pool, 0); 1314 1315 /* 1316 * Sync the updated config cache. 1317 */ 1318 spa_config_sync(spa, B_FALSE, B_TRUE); 1319 1320 spa_close(spa, FTAG); 1321 1322 mutex_exit(&spa_namespace_lock); 1323 1324 return (0); 1325 } 1326 1327 /* 1328 * Return the spa_t associated with given pool_guid, if it exists. If 1329 * device_guid is non-zero, determine whether the pool exists *and* contains 1330 * a device with the specified device_guid. 1331 */ 1332 spa_t * 1333 spa_by_guid(uint64_t pool_guid, uint64_t device_guid) 1334 { 1335 spa_t *spa; 1336 avl_tree_t *t = &spa_namespace_avl; 1337 1338 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 1339 1340 for (spa = avl_first(t); spa != NULL; spa = AVL_NEXT(t, spa)) { 1341 if (spa->spa_state == POOL_STATE_UNINITIALIZED) 1342 continue; 1343 if (spa->spa_root_vdev == NULL) 1344 continue; 1345 if (spa_guid(spa) == pool_guid) { 1346 if (device_guid == 0) 1347 break; 1348 1349 if (vdev_lookup_by_guid(spa->spa_root_vdev, 1350 device_guid) != NULL) 1351 break; 1352 1353 /* 1354 * Check any devices we may be in the process of adding. 1355 */ 1356 if (spa->spa_pending_vdev) { 1357 if (vdev_lookup_by_guid(spa->spa_pending_vdev, 1358 device_guid) != NULL) 1359 break; 1360 } 1361 } 1362 } 1363 1364 return (spa); 1365 } 1366 1367 /* 1368 * Determine whether a pool with the given pool_guid exists. 1369 */ 1370 boolean_t 1371 spa_guid_exists(uint64_t pool_guid, uint64_t device_guid) 1372 { 1373 return (spa_by_guid(pool_guid, device_guid) != NULL); 1374 } 1375 1376 char * 1377 spa_strdup(const char *s) 1378 { 1379 size_t len; 1380 char *new; 1381 1382 len = strlen(s); 1383 new = kmem_alloc(len + 1, KM_SLEEP); 1384 bcopy(s, new, len); 1385 new[len] = '\0'; 1386 1387 return (new); 1388 } 1389 1390 void 1391 spa_strfree(char *s) 1392 { 1393 kmem_free(s, strlen(s) + 1); 1394 } 1395 1396 uint64_t 1397 spa_get_random(uint64_t range) 1398 { 1399 uint64_t r; 1400 1401 ASSERT(range != 0); 1402 1403 (void) random_get_pseudo_bytes((void *)&r, sizeof (uint64_t)); 1404 1405 return (r % range); 1406 } 1407 1408 uint64_t 1409 spa_generate_guid(spa_t *spa) 1410 { 1411 uint64_t guid = spa_get_random(-1ULL); 1412 1413 if (spa != NULL) { 1414 while (guid == 0 || spa_guid_exists(spa_guid(spa), guid)) 1415 guid = spa_get_random(-1ULL); 1416 } else { 1417 while (guid == 0 || spa_guid_exists(guid, 0)) 1418 guid = spa_get_random(-1ULL); 1419 } 1420 1421 return (guid); 1422 } 1423 1424 void 1425 snprintf_blkptr(char *buf, size_t buflen, const blkptr_t *bp) 1426 { 1427 char type[256]; 1428 char *checksum = NULL; 1429 char *compress = NULL; 1430 1431 if (bp != NULL) { 1432 if (BP_GET_TYPE(bp) & DMU_OT_NEWTYPE) { 1433 dmu_object_byteswap_t bswap = 1434 DMU_OT_BYTESWAP(BP_GET_TYPE(bp)); 1435 (void) snprintf(type, sizeof (type), "bswap %s %s", 1436 DMU_OT_IS_METADATA(BP_GET_TYPE(bp)) ? 1437 "metadata" : "data", 1438 dmu_ot_byteswap[bswap].ob_name); 1439 } else { 1440 (void) strlcpy(type, dmu_ot[BP_GET_TYPE(bp)].ot_name, 1441 sizeof (type)); 1442 } 1443 if (!BP_IS_EMBEDDED(bp)) { 1444 checksum = 1445 zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_name; 1446 } 1447 compress = zio_compress_table[BP_GET_COMPRESS(bp)].ci_name; 1448 } 1449 1450 SNPRINTF_BLKPTR(snprintf, ' ', buf, buflen, bp, type, checksum, 1451 compress); 1452 } 1453 1454 void 1455 spa_freeze(spa_t *spa) 1456 { 1457 uint64_t freeze_txg = 0; 1458 1459 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1460 if (spa->spa_freeze_txg == UINT64_MAX) { 1461 freeze_txg = spa_last_synced_txg(spa) + TXG_SIZE; 1462 spa->spa_freeze_txg = freeze_txg; 1463 } 1464 spa_config_exit(spa, SCL_ALL, FTAG); 1465 if (freeze_txg != 0) 1466 txg_wait_synced(spa_get_dsl(spa), freeze_txg); 1467 } 1468 1469 void 1470 zfs_panic_recover(const char *fmt, ...) 1471 { 1472 va_list adx; 1473 1474 va_start(adx, fmt); 1475 vcmn_err(zfs_recover ? CE_WARN : CE_PANIC, fmt, adx); 1476 va_end(adx); 1477 } 1478 1479 /* 1480 * This is a stripped-down version of strtoull, suitable only for converting 1481 * lowercase hexadecimal numbers that don't overflow. 1482 */ 1483 uint64_t 1484 strtonum(const char *str, char **nptr) 1485 { 1486 uint64_t val = 0; 1487 char c; 1488 int digit; 1489 1490 while ((c = *str) != '\0') { 1491 if (c >= '0' && c <= '9') 1492 digit = c - '0'; 1493 else if (c >= 'a' && c <= 'f') 1494 digit = 10 + c - 'a'; 1495 else 1496 break; 1497 1498 val *= 16; 1499 val += digit; 1500 1501 str++; 1502 } 1503 1504 if (nptr) 1505 *nptr = (char *)str; 1506 1507 return (val); 1508 } 1509 1510 /* 1511 * ========================================================================== 1512 * Accessor functions 1513 * ========================================================================== 1514 */ 1515 1516 boolean_t 1517 spa_shutting_down(spa_t *spa) 1518 { 1519 return (spa->spa_async_suspended); 1520 } 1521 1522 dsl_pool_t * 1523 spa_get_dsl(spa_t *spa) 1524 { 1525 return (spa->spa_dsl_pool); 1526 } 1527 1528 boolean_t 1529 spa_is_initializing(spa_t *spa) 1530 { 1531 return (spa->spa_is_initializing); 1532 } 1533 1534 blkptr_t * 1535 spa_get_rootblkptr(spa_t *spa) 1536 { 1537 return (&spa->spa_ubsync.ub_rootbp); 1538 } 1539 1540 void 1541 spa_set_rootblkptr(spa_t *spa, const blkptr_t *bp) 1542 { 1543 spa->spa_uberblock.ub_rootbp = *bp; 1544 } 1545 1546 void 1547 spa_altroot(spa_t *spa, char *buf, size_t buflen) 1548 { 1549 if (spa->spa_root == NULL) 1550 buf[0] = '\0'; 1551 else 1552 (void) strncpy(buf, spa->spa_root, buflen); 1553 } 1554 1555 int 1556 spa_sync_pass(spa_t *spa) 1557 { 1558 return (spa->spa_sync_pass); 1559 } 1560 1561 char * 1562 spa_name(spa_t *spa) 1563 { 1564 return (spa->spa_name); 1565 } 1566 1567 uint64_t 1568 spa_guid(spa_t *spa) 1569 { 1570 dsl_pool_t *dp = spa_get_dsl(spa); 1571 uint64_t guid; 1572 1573 /* 1574 * If we fail to parse the config during spa_load(), we can go through 1575 * the error path (which posts an ereport) and end up here with no root 1576 * vdev. We stash the original pool guid in 'spa_config_guid' to handle 1577 * this case. 1578 */ 1579 if (spa->spa_root_vdev == NULL) 1580 return (spa->spa_config_guid); 1581 1582 guid = spa->spa_last_synced_guid != 0 ? 1583 spa->spa_last_synced_guid : spa->spa_root_vdev->vdev_guid; 1584 1585 /* 1586 * Return the most recently synced out guid unless we're 1587 * in syncing context. 1588 */ 1589 if (dp && dsl_pool_sync_context(dp)) 1590 return (spa->spa_root_vdev->vdev_guid); 1591 else 1592 return (guid); 1593 } 1594 1595 uint64_t 1596 spa_load_guid(spa_t *spa) 1597 { 1598 /* 1599 * This is a GUID that exists solely as a reference for the 1600 * purposes of the arc. It is generated at load time, and 1601 * is never written to persistent storage. 1602 */ 1603 return (spa->spa_load_guid); 1604 } 1605 1606 uint64_t 1607 spa_last_synced_txg(spa_t *spa) 1608 { 1609 return (spa->spa_ubsync.ub_txg); 1610 } 1611 1612 uint64_t 1613 spa_first_txg(spa_t *spa) 1614 { 1615 return (spa->spa_first_txg); 1616 } 1617 1618 uint64_t 1619 spa_syncing_txg(spa_t *spa) 1620 { 1621 return (spa->spa_syncing_txg); 1622 } 1623 1624 pool_state_t 1625 spa_state(spa_t *spa) 1626 { 1627 return (spa->spa_state); 1628 } 1629 1630 spa_load_state_t 1631 spa_load_state(spa_t *spa) 1632 { 1633 return (spa->spa_load_state); 1634 } 1635 1636 uint64_t 1637 spa_freeze_txg(spa_t *spa) 1638 { 1639 return (spa->spa_freeze_txg); 1640 } 1641 1642 /* ARGSUSED */ 1643 uint64_t 1644 spa_get_worst_case_asize(spa_t *spa, uint64_t lsize) 1645 { 1646 return (lsize * spa_asize_inflation); 1647 } 1648 1649 /* 1650 * Return the amount of slop space in bytes. It is 1/32 of the pool (3.2%), 1651 * or at least 128MB, unless that would cause it to be more than half the 1652 * pool size. 1653 * 1654 * See the comment above spa_slop_shift for details. 1655 */ 1656 uint64_t 1657 spa_get_slop_space(spa_t *spa) 1658 { 1659 uint64_t space = spa_get_dspace(spa); 1660 return (MAX(space >> spa_slop_shift, MIN(space >> 1, spa_min_slop))); 1661 } 1662 1663 uint64_t 1664 spa_get_dspace(spa_t *spa) 1665 { 1666 return (spa->spa_dspace); 1667 } 1668 1669 void 1670 spa_update_dspace(spa_t *spa) 1671 { 1672 spa->spa_dspace = metaslab_class_get_dspace(spa_normal_class(spa)) + 1673 ddt_get_dedup_dspace(spa); 1674 } 1675 1676 /* 1677 * Return the failure mode that has been set to this pool. The default 1678 * behavior will be to block all I/Os when a complete failure occurs. 1679 */ 1680 uint8_t 1681 spa_get_failmode(spa_t *spa) 1682 { 1683 return (spa->spa_failmode); 1684 } 1685 1686 boolean_t 1687 spa_suspended(spa_t *spa) 1688 { 1689 return (spa->spa_suspended); 1690 } 1691 1692 uint64_t 1693 spa_version(spa_t *spa) 1694 { 1695 return (spa->spa_ubsync.ub_version); 1696 } 1697 1698 boolean_t 1699 spa_deflate(spa_t *spa) 1700 { 1701 return (spa->spa_deflate); 1702 } 1703 1704 metaslab_class_t * 1705 spa_normal_class(spa_t *spa) 1706 { 1707 return (spa->spa_normal_class); 1708 } 1709 1710 metaslab_class_t * 1711 spa_log_class(spa_t *spa) 1712 { 1713 return (spa->spa_log_class); 1714 } 1715 1716 void 1717 spa_evicting_os_register(spa_t *spa, objset_t *os) 1718 { 1719 mutex_enter(&spa->spa_evicting_os_lock); 1720 list_insert_head(&spa->spa_evicting_os_list, os); 1721 mutex_exit(&spa->spa_evicting_os_lock); 1722 } 1723 1724 void 1725 spa_evicting_os_deregister(spa_t *spa, objset_t *os) 1726 { 1727 mutex_enter(&spa->spa_evicting_os_lock); 1728 list_remove(&spa->spa_evicting_os_list, os); 1729 cv_broadcast(&spa->spa_evicting_os_cv); 1730 mutex_exit(&spa->spa_evicting_os_lock); 1731 } 1732 1733 void 1734 spa_evicting_os_wait(spa_t *spa) 1735 { 1736 mutex_enter(&spa->spa_evicting_os_lock); 1737 while (!list_is_empty(&spa->spa_evicting_os_list)) 1738 cv_wait(&spa->spa_evicting_os_cv, &spa->spa_evicting_os_lock); 1739 mutex_exit(&spa->spa_evicting_os_lock); 1740 1741 dmu_buf_user_evict_wait(); 1742 } 1743 1744 int 1745 spa_max_replication(spa_t *spa) 1746 { 1747 /* 1748 * As of SPA_VERSION == SPA_VERSION_DITTO_BLOCKS, we are able to 1749 * handle BPs with more than one DVA allocated. Set our max 1750 * replication level accordingly. 1751 */ 1752 if (spa_version(spa) < SPA_VERSION_DITTO_BLOCKS) 1753 return (1); 1754 return (MIN(SPA_DVAS_PER_BP, spa_max_replication_override)); 1755 } 1756 1757 int 1758 spa_prev_software_version(spa_t *spa) 1759 { 1760 return (spa->spa_prev_software_version); 1761 } 1762 1763 uint64_t 1764 spa_deadman_synctime(spa_t *spa) 1765 { 1766 return (spa->spa_deadman_synctime); 1767 } 1768 1769 uint64_t 1770 dva_get_dsize_sync(spa_t *spa, const dva_t *dva) 1771 { 1772 uint64_t asize = DVA_GET_ASIZE(dva); 1773 uint64_t dsize = asize; 1774 1775 ASSERT(spa_config_held(spa, SCL_ALL, RW_READER) != 0); 1776 1777 if (asize != 0 && spa->spa_deflate) { 1778 vdev_t *vd = vdev_lookup_top(spa, DVA_GET_VDEV(dva)); 1779 dsize = (asize >> SPA_MINBLOCKSHIFT) * vd->vdev_deflate_ratio; 1780 } 1781 1782 return (dsize); 1783 } 1784 1785 uint64_t 1786 bp_get_dsize_sync(spa_t *spa, const blkptr_t *bp) 1787 { 1788 uint64_t dsize = 0; 1789 1790 for (int d = 0; d < BP_GET_NDVAS(bp); d++) 1791 dsize += dva_get_dsize_sync(spa, &bp->blk_dva[d]); 1792 1793 return (dsize); 1794 } 1795 1796 uint64_t 1797 bp_get_dsize(spa_t *spa, const blkptr_t *bp) 1798 { 1799 uint64_t dsize = 0; 1800 1801 spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); 1802 1803 for (int d = 0; d < BP_GET_NDVAS(bp); d++) 1804 dsize += dva_get_dsize_sync(spa, &bp->blk_dva[d]); 1805 1806 spa_config_exit(spa, SCL_VDEV, FTAG); 1807 1808 return (dsize); 1809 } 1810 1811 /* 1812 * ========================================================================== 1813 * Initialization and Termination 1814 * ========================================================================== 1815 */ 1816 1817 static int 1818 spa_name_compare(const void *a1, const void *a2) 1819 { 1820 const spa_t *s1 = a1; 1821 const spa_t *s2 = a2; 1822 int s; 1823 1824 s = strcmp(s1->spa_name, s2->spa_name); 1825 if (s > 0) 1826 return (1); 1827 if (s < 0) 1828 return (-1); 1829 return (0); 1830 } 1831 1832 int 1833 spa_busy(void) 1834 { 1835 return (spa_active_count); 1836 } 1837 1838 void 1839 spa_boot_init() 1840 { 1841 spa_config_load(); 1842 } 1843 1844 void 1845 spa_init(int mode) 1846 { 1847 mutex_init(&spa_namespace_lock, NULL, MUTEX_DEFAULT, NULL); 1848 mutex_init(&spa_spare_lock, NULL, MUTEX_DEFAULT, NULL); 1849 mutex_init(&spa_l2cache_lock, NULL, MUTEX_DEFAULT, NULL); 1850 cv_init(&spa_namespace_cv, NULL, CV_DEFAULT, NULL); 1851 1852 avl_create(&spa_namespace_avl, spa_name_compare, sizeof (spa_t), 1853 offsetof(spa_t, spa_avl)); 1854 1855 avl_create(&spa_spare_avl, spa_spare_compare, sizeof (spa_aux_t), 1856 offsetof(spa_aux_t, aux_avl)); 1857 1858 avl_create(&spa_l2cache_avl, spa_l2cache_compare, sizeof (spa_aux_t), 1859 offsetof(spa_aux_t, aux_avl)); 1860 1861 spa_mode_global = mode; 1862 1863 #ifdef _KERNEL 1864 spa_arch_init(); 1865 #else 1866 if (spa_mode_global != FREAD && dprintf_find_string("watch")) { 1867 arc_procfd = open("/proc/self/ctl", O_WRONLY); 1868 if (arc_procfd == -1) { 1869 perror("could not enable watchpoints: " 1870 "opening /proc/self/ctl failed: "); 1871 } else { 1872 arc_watch = B_TRUE; 1873 } 1874 } 1875 #endif 1876 1877 refcount_init(); 1878 unique_init(); 1879 range_tree_init(); 1880 metaslab_alloc_trace_init(); 1881 zio_init(); 1882 dmu_init(); 1883 zil_init(); 1884 vdev_cache_stat_init(); 1885 zfs_prop_init(); 1886 zpool_prop_init(); 1887 zpool_feature_init(); 1888 spa_config_load(); 1889 l2arc_start(); 1890 } 1891 1892 void 1893 spa_fini(void) 1894 { 1895 l2arc_stop(); 1896 1897 spa_evict_all(); 1898 1899 vdev_cache_stat_fini(); 1900 zil_fini(); 1901 dmu_fini(); 1902 zio_fini(); 1903 metaslab_alloc_trace_fini(); 1904 range_tree_fini(); 1905 unique_fini(); 1906 refcount_fini(); 1907 1908 avl_destroy(&spa_namespace_avl); 1909 avl_destroy(&spa_spare_avl); 1910 avl_destroy(&spa_l2cache_avl); 1911 1912 cv_destroy(&spa_namespace_cv); 1913 mutex_destroy(&spa_namespace_lock); 1914 mutex_destroy(&spa_spare_lock); 1915 mutex_destroy(&spa_l2cache_lock); 1916 } 1917 1918 /* 1919 * Return whether this pool has slogs. No locking needed. 1920 * It's not a problem if the wrong answer is returned as it's only for 1921 * performance and not correctness 1922 */ 1923 boolean_t 1924 spa_has_slogs(spa_t *spa) 1925 { 1926 return (spa->spa_log_class->mc_rotor != NULL); 1927 } 1928 1929 spa_log_state_t 1930 spa_get_log_state(spa_t *spa) 1931 { 1932 return (spa->spa_log_state); 1933 } 1934 1935 void 1936 spa_set_log_state(spa_t *spa, spa_log_state_t state) 1937 { 1938 spa->spa_log_state = state; 1939 } 1940 1941 boolean_t 1942 spa_is_root(spa_t *spa) 1943 { 1944 return (spa->spa_is_root); 1945 } 1946 1947 boolean_t 1948 spa_writeable(spa_t *spa) 1949 { 1950 return (!!(spa->spa_mode & FWRITE)); 1951 } 1952 1953 /* 1954 * Returns true if there is a pending sync task in any of the current 1955 * syncing txg, the current quiescing txg, or the current open txg. 1956 */ 1957 boolean_t 1958 spa_has_pending_synctask(spa_t *spa) 1959 { 1960 return (!txg_all_lists_empty(&spa->spa_dsl_pool->dp_sync_tasks)); 1961 } 1962 1963 int 1964 spa_mode(spa_t *spa) 1965 { 1966 return (spa->spa_mode); 1967 } 1968 1969 uint64_t 1970 spa_bootfs(spa_t *spa) 1971 { 1972 return (spa->spa_bootfs); 1973 } 1974 1975 uint64_t 1976 spa_delegation(spa_t *spa) 1977 { 1978 return (spa->spa_delegation); 1979 } 1980 1981 objset_t * 1982 spa_meta_objset(spa_t *spa) 1983 { 1984 return (spa->spa_meta_objset); 1985 } 1986 1987 enum zio_checksum 1988 spa_dedup_checksum(spa_t *spa) 1989 { 1990 return (spa->spa_dedup_checksum); 1991 } 1992 1993 /* 1994 * Reset pool scan stat per scan pass (or reboot). 1995 */ 1996 void 1997 spa_scan_stat_init(spa_t *spa) 1998 { 1999 /* data not stored on disk */ 2000 spa->spa_scan_pass_start = gethrestime_sec(); 2001 spa->spa_scan_pass_exam = 0; 2002 vdev_scan_stat_init(spa->spa_root_vdev); 2003 } 2004 2005 /* 2006 * Get scan stats for zpool status reports 2007 */ 2008 int 2009 spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps) 2010 { 2011 dsl_scan_t *scn = spa->spa_dsl_pool ? spa->spa_dsl_pool->dp_scan : NULL; 2012 2013 if (scn == NULL || scn->scn_phys.scn_func == POOL_SCAN_NONE) 2014 return (SET_ERROR(ENOENT)); 2015 bzero(ps, sizeof (pool_scan_stat_t)); 2016 2017 /* data stored on disk */ 2018 ps->pss_func = scn->scn_phys.scn_func; 2019 ps->pss_start_time = scn->scn_phys.scn_start_time; 2020 ps->pss_end_time = scn->scn_phys.scn_end_time; 2021 ps->pss_to_examine = scn->scn_phys.scn_to_examine; 2022 ps->pss_examined = scn->scn_phys.scn_examined; 2023 ps->pss_to_process = scn->scn_phys.scn_to_process; 2024 ps->pss_processed = scn->scn_phys.scn_processed; 2025 ps->pss_errors = scn->scn_phys.scn_errors; 2026 ps->pss_state = scn->scn_phys.scn_state; 2027 2028 /* data not stored on disk */ 2029 ps->pss_pass_start = spa->spa_scan_pass_start; 2030 ps->pss_pass_exam = spa->spa_scan_pass_exam; 2031 2032 return (0); 2033 } 2034 2035 boolean_t 2036 spa_debug_enabled(spa_t *spa) 2037 { 2038 return (spa->spa_debug); 2039 } 2040 2041 int 2042 spa_maxblocksize(spa_t *spa) 2043 { 2044 if (spa_feature_is_enabled(spa, SPA_FEATURE_LARGE_BLOCKS)) 2045 return (SPA_MAXBLOCKSIZE); 2046 else 2047 return (SPA_OLD_MAXBLOCKSIZE); 2048 } 2049