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.
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.
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]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
25 #include <sys/zfs_context.h>
26 #include <sys/spa_impl.h>
28 #include <sys/zio_checksum.h>
29 #include <sys/zio_compress.h>
31 #include <sys/dmu_tx.h>
34 #include <sys/vdev_impl.h>
35 #include <sys/metaslab.h>
36 #include <sys/uberblock_impl.h>
39 #include <sys/unique.h>
40 #include <sys/dsl_pool.h>
41 #include <sys/dsl_dir.h>
42 #include <sys/dsl_prop.h>
43 #include <sys/dsl_scan.h>
44 #include <sys/fs/zfs.h>
45 #include <sys/metaslab_impl.h>
53 * There are four basic locks for managing spa_t structures:
55 * spa_namespace_lock (global mutex)
57 * This lock must be acquired to do any of the following:
59 * - Lookup a spa_t by name
60 * - Add or remove a spa_t from the namespace
61 * - Increase spa_refcount from non-zero
62 * - Check if spa_refcount is zero
64 * - add/remove/attach/detach devices
65 * - Held for the duration of create/destroy/import/export
67 * It does not need to handle recursion. A create or destroy may
68 * reference objects (files or zvols) in other pools, but by
69 * definition they must have an existing reference, and will never need
70 * to lookup a spa_t by name.
72 * spa_refcount (per-spa refcount_t protected by mutex)
74 * This reference count keep track of any active users of the spa_t. The
75 * spa_t cannot be destroyed or freed while this is non-zero. Internally,
76 * the refcount is never really 'zero' - opening a pool implicitly keeps
77 * some references in the DMU. Internally we check against spa_minref, but
78 * present the image of a zero/non-zero value to consumers.
80 * spa_config_lock[] (per-spa array of rwlocks)
82 * This protects the spa_t from config changes, and must be held in
83 * the following circumstances:
85 * - RW_READER to perform I/O to the spa
86 * - RW_WRITER to change the vdev config
88 * The locking order is fairly straightforward:
90 * spa_namespace_lock -> spa_refcount
92 * The namespace lock must be acquired to increase the refcount from 0
93 * or to check if it is zero.
95 * spa_refcount -> spa_config_lock[]
97 * There must be at least one valid reference on the spa_t to acquire
100 * spa_namespace_lock -> spa_config_lock[]
102 * The namespace lock must always be taken before the config lock.
105 * The spa_namespace_lock can be acquired directly and is globally visible.
107 * The namespace is manipulated using the following functions, all of which
108 * require the spa_namespace_lock to be held.
110 * spa_lookup() Lookup a spa_t by name.
112 * spa_add() Create a new spa_t in the namespace.
114 * spa_remove() Remove a spa_t from the namespace. This also
115 * frees up any memory associated with the spa_t.
117 * spa_next() Returns the next spa_t in the system, or the
118 * first if NULL is passed.
120 * spa_evict_all() Shutdown and remove all spa_t structures in
123 * spa_guid_exists() Determine whether a pool/device guid exists.
125 * The spa_refcount is manipulated using the following functions:
127 * spa_open_ref() Adds a reference to the given spa_t. Must be
128 * called with spa_namespace_lock held if the
129 * refcount is currently zero.
131 * spa_close() Remove a reference from the spa_t. This will
132 * not free the spa_t or remove it from the
133 * namespace. No locking is required.
135 * spa_refcount_zero() Returns true if the refcount is currently
136 * zero. Must be called with spa_namespace_lock
139 * The spa_config_lock[] is an array of rwlocks, ordered as follows:
140 * SCL_CONFIG > SCL_STATE > SCL_ALLOC > SCL_ZIO > SCL_FREE > SCL_VDEV.
141 * spa_config_lock[] is manipulated with spa_config_{enter,exit,held}().
143 * To read the configuration, it suffices to hold one of these locks as reader.
144 * To modify the configuration, you must hold all locks as writer. To modify
145 * vdev state without altering the vdev tree's topology (e.g. online/offline),
146 * you must hold SCL_STATE and SCL_ZIO as writer.
148 * We use these distinct config locks to avoid recursive lock entry.
149 * For example, spa_sync() (which holds SCL_CONFIG as reader) induces
150 * block allocations (SCL_ALLOC), which may require reading space maps
151 * from disk (dmu_read() -> zio_read() -> SCL_ZIO).
153 * The spa config locks cannot be normal rwlocks because we need the
154 * ability to hand off ownership. For example, SCL_ZIO is acquired
155 * by the issuing thread and later released by an interrupt thread.
156 * They do, however, obey the usual write-wanted semantics to prevent
157 * writer (i.e. system administrator) starvation.
159 * The lock acquisition rules are as follows:
162 * Protects changes to the vdev tree topology, such as vdev
163 * add/remove/attach/detach. Protects the dirty config list
164 * (spa_config_dirty_list) and the set of spares and l2arc devices.
167 * Protects changes to pool state and vdev state, such as vdev
168 * online/offline/fault/degrade/clear. Protects the dirty state list
169 * (spa_state_dirty_list) and global pool state (spa_state).
172 * Protects changes to metaslab groups and classes.
173 * Held as reader by metaslab_alloc() and metaslab_claim().
176 * Held by bp-level zios (those which have no io_vd upon entry)
177 * to prevent changes to the vdev tree. The bp-level zio implicitly
178 * protects all of its vdev child zios, which do not hold SCL_ZIO.
181 * Protects changes to metaslab groups and classes.
182 * Held as reader by metaslab_free(). SCL_FREE is distinct from
183 * SCL_ALLOC, and lower than SCL_ZIO, so that we can safely free
184 * blocks in zio_done() while another i/o that holds either
185 * SCL_ALLOC or SCL_ZIO is waiting for this i/o to complete.
188 * Held as reader to prevent changes to the vdev tree during trivial
189 * inquiries such as bp_get_dsize(). SCL_VDEV is distinct from the
190 * other locks, and lower than all of them, to ensure that it's safe
191 * to acquire regardless of caller context.
193 * In addition, the following rules apply:
195 * (a) spa_props_lock protects pool properties, spa_config and spa_config_list.
196 * The lock ordering is SCL_CONFIG > spa_props_lock.
198 * (b) I/O operations on leaf vdevs. For any zio operation that takes
199 * an explicit vdev_t argument -- such as zio_ioctl(), zio_read_phys(),
200 * or zio_write_phys() -- the caller must ensure that the config cannot
201 * cannot change in the interim, and that the vdev cannot be reopened.
202 * SCL_STATE as reader suffices for both.
204 * The vdev configuration is protected by spa_vdev_enter() / spa_vdev_exit().
206 * spa_vdev_enter() Acquire the namespace lock and the config lock
209 * spa_vdev_exit() Release the config lock, wait for all I/O
210 * to complete, sync the updated configs to the
211 * cache, and release the namespace lock.
213 * vdev state is protected by spa_vdev_state_enter() / spa_vdev_state_exit().
214 * Like spa_vdev_enter/exit, these are convenience wrappers -- the actual
215 * locking is, always, based on spa_namespace_lock and spa_config_lock[].
217 * spa_rename() is also implemented within this file since is requires
218 * manipulation of the namespace.
221 static avl_tree_t spa_namespace_avl
;
222 kmutex_t spa_namespace_lock
;
223 static kcondvar_t spa_namespace_cv
;
224 static int spa_active_count
;
225 int spa_max_replication_override
= SPA_DVAS_PER_BP
;
227 static kmutex_t spa_spare_lock
;
228 static avl_tree_t spa_spare_avl
;
229 static kmutex_t spa_l2cache_lock
;
230 static avl_tree_t spa_l2cache_avl
;
232 kmem_cache_t
*spa_buffer_pool
;
236 /* Everything except dprintf is on by default in debug builds */
237 int zfs_flags
= ~ZFS_DEBUG_DPRINTF
;
243 * zfs_recover can be set to nonzero to attempt to recover from
244 * otherwise-fatal errors, typically caused by on-disk corruption. When
245 * set, calls to zfs_panic_recover() will turn into warning messages.
251 * ==========================================================================
253 * ==========================================================================
256 spa_config_lock_init(spa_t
*spa
)
258 for (int i
= 0; i
< SCL_LOCKS
; i
++) {
259 spa_config_lock_t
*scl
= &spa
->spa_config_lock
[i
];
260 mutex_init(&scl
->scl_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
261 cv_init(&scl
->scl_cv
, NULL
, CV_DEFAULT
, NULL
);
262 refcount_create(&scl
->scl_count
);
263 scl
->scl_writer
= NULL
;
264 scl
->scl_write_wanted
= 0;
269 spa_config_lock_destroy(spa_t
*spa
)
271 for (int i
= 0; i
< SCL_LOCKS
; i
++) {
272 spa_config_lock_t
*scl
= &spa
->spa_config_lock
[i
];
273 mutex_destroy(&scl
->scl_lock
);
274 cv_destroy(&scl
->scl_cv
);
275 refcount_destroy(&scl
->scl_count
);
276 ASSERT(scl
->scl_writer
== NULL
);
277 ASSERT(scl
->scl_write_wanted
== 0);
282 spa_config_tryenter(spa_t
*spa
, int locks
, void *tag
, krw_t rw
)
284 for (int i
= 0; i
< SCL_LOCKS
; i
++) {
285 spa_config_lock_t
*scl
= &spa
->spa_config_lock
[i
];
286 if (!(locks
& (1 << i
)))
288 mutex_enter(&scl
->scl_lock
);
289 if (rw
== RW_READER
) {
290 if (scl
->scl_writer
|| scl
->scl_write_wanted
) {
291 mutex_exit(&scl
->scl_lock
);
292 spa_config_exit(spa
, locks
^ (1 << i
), tag
);
296 ASSERT(scl
->scl_writer
!= curthread
);
297 if (!refcount_is_zero(&scl
->scl_count
)) {
298 mutex_exit(&scl
->scl_lock
);
299 spa_config_exit(spa
, locks
^ (1 << i
), tag
);
302 scl
->scl_writer
= curthread
;
304 (void) refcount_add(&scl
->scl_count
, tag
);
305 mutex_exit(&scl
->scl_lock
);
311 spa_config_enter(spa_t
*spa
, int locks
, void *tag
, krw_t rw
)
315 for (int i
= 0; i
< SCL_LOCKS
; i
++) {
316 spa_config_lock_t
*scl
= &spa
->spa_config_lock
[i
];
317 if (scl
->scl_writer
== curthread
)
318 wlocks_held
|= (1 << i
);
319 if (!(locks
& (1 << i
)))
321 mutex_enter(&scl
->scl_lock
);
322 if (rw
== RW_READER
) {
323 while (scl
->scl_writer
|| scl
->scl_write_wanted
) {
324 cv_wait(&scl
->scl_cv
, &scl
->scl_lock
);
327 ASSERT(scl
->scl_writer
!= curthread
);
328 while (!refcount_is_zero(&scl
->scl_count
)) {
329 scl
->scl_write_wanted
++;
330 cv_wait(&scl
->scl_cv
, &scl
->scl_lock
);
331 scl
->scl_write_wanted
--;
333 scl
->scl_writer
= curthread
;
335 (void) refcount_add(&scl
->scl_count
, tag
);
336 mutex_exit(&scl
->scl_lock
);
338 ASSERT(wlocks_held
<= locks
);
342 spa_config_exit(spa_t
*spa
, int locks
, void *tag
)
344 for (int i
= SCL_LOCKS
- 1; i
>= 0; i
--) {
345 spa_config_lock_t
*scl
= &spa
->spa_config_lock
[i
];
346 if (!(locks
& (1 << i
)))
348 mutex_enter(&scl
->scl_lock
);
349 ASSERT(!refcount_is_zero(&scl
->scl_count
));
350 if (refcount_remove(&scl
->scl_count
, tag
) == 0) {
351 ASSERT(scl
->scl_writer
== NULL
||
352 scl
->scl_writer
== curthread
);
353 scl
->scl_writer
= NULL
; /* OK in either case */
354 cv_broadcast(&scl
->scl_cv
);
356 mutex_exit(&scl
->scl_lock
);
361 spa_config_held(spa_t
*spa
, int locks
, krw_t rw
)
365 for (int i
= 0; i
< SCL_LOCKS
; i
++) {
366 spa_config_lock_t
*scl
= &spa
->spa_config_lock
[i
];
367 if (!(locks
& (1 << i
)))
369 if ((rw
== RW_READER
&& !refcount_is_zero(&scl
->scl_count
)) ||
370 (rw
== RW_WRITER
&& scl
->scl_writer
== curthread
))
371 locks_held
|= 1 << i
;
378 * ==========================================================================
379 * SPA namespace functions
380 * ==========================================================================
384 * Lookup the named spa_t in the AVL tree. The spa_namespace_lock must be held.
385 * Returns NULL if no matching spa_t is found.
388 spa_lookup(const char *name
)
390 static spa_t search
; /* spa_t is large; don't allocate on stack */
396 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
399 * If it's a full dataset name, figure out the pool name and
402 cp
= strpbrk(name
, "/@");
408 (void) strlcpy(search
.spa_name
, name
, sizeof (search
.spa_name
));
409 spa
= avl_find(&spa_namespace_avl
, &search
, &where
);
418 * Create an uninitialized spa_t with the given name. Requires
419 * spa_namespace_lock. The caller must ensure that the spa_t doesn't already
420 * exist by calling spa_lookup() first.
423 spa_add(const char *name
, nvlist_t
*config
, const char *altroot
)
426 spa_config_dirent_t
*dp
;
428 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
430 spa
= kmem_zalloc(sizeof (spa_t
), KM_SLEEP
);
432 mutex_init(&spa
->spa_async_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
433 mutex_init(&spa
->spa_errlist_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
434 mutex_init(&spa
->spa_errlog_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
435 mutex_init(&spa
->spa_history_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
436 mutex_init(&spa
->spa_proc_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
437 mutex_init(&spa
->spa_props_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
438 mutex_init(&spa
->spa_scrub_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
439 mutex_init(&spa
->spa_suspend_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
440 mutex_init(&spa
->spa_vdev_top_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
442 cv_init(&spa
->spa_async_cv
, NULL
, CV_DEFAULT
, NULL
);
443 cv_init(&spa
->spa_proc_cv
, NULL
, CV_DEFAULT
, NULL
);
444 cv_init(&spa
->spa_scrub_io_cv
, NULL
, CV_DEFAULT
, NULL
);
445 cv_init(&spa
->spa_suspend_cv
, NULL
, CV_DEFAULT
, NULL
);
447 for (int t
= 0; t
< TXG_SIZE
; t
++)
448 bplist_create(&spa
->spa_free_bplist
[t
]);
450 (void) strlcpy(spa
->spa_name
, name
, sizeof (spa
->spa_name
));
451 spa
->spa_state
= POOL_STATE_UNINITIALIZED
;
452 spa
->spa_freeze_txg
= UINT64_MAX
;
453 spa
->spa_final_txg
= UINT64_MAX
;
454 spa
->spa_load_max_txg
= UINT64_MAX
;
456 spa
->spa_proc_state
= SPA_PROC_NONE
;
458 refcount_create(&spa
->spa_refcount
);
459 spa_config_lock_init(spa
);
461 avl_add(&spa_namespace_avl
, spa
);
464 * Set the alternate root, if there is one.
467 spa
->spa_root
= spa_strdup(altroot
);
472 * Every pool starts with the default cachefile
474 list_create(&spa
->spa_config_list
, sizeof (spa_config_dirent_t
),
475 offsetof(spa_config_dirent_t
, scd_link
));
477 dp
= kmem_zalloc(sizeof (spa_config_dirent_t
), KM_SLEEP
);
478 dp
->scd_path
= altroot
? NULL
: spa_strdup(spa_config_path
);
479 list_insert_head(&spa
->spa_config_list
, dp
);
481 VERIFY(nvlist_alloc(&spa
->spa_load_info
, NV_UNIQUE_NAME
,
485 VERIFY(nvlist_dup(config
, &spa
->spa_config
, 0) == 0);
491 * Removes a spa_t from the namespace, freeing up any memory used. Requires
492 * spa_namespace_lock. This is called only after the spa_t has been closed and
496 spa_remove(spa_t
*spa
)
498 spa_config_dirent_t
*dp
;
500 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
501 ASSERT(spa
->spa_state
== POOL_STATE_UNINITIALIZED
);
503 nvlist_free(spa
->spa_config_splitting
);
505 avl_remove(&spa_namespace_avl
, spa
);
506 cv_broadcast(&spa_namespace_cv
);
509 spa_strfree(spa
->spa_root
);
513 while ((dp
= list_head(&spa
->spa_config_list
)) != NULL
) {
514 list_remove(&spa
->spa_config_list
, dp
);
515 if (dp
->scd_path
!= NULL
)
516 spa_strfree(dp
->scd_path
);
517 kmem_free(dp
, sizeof (spa_config_dirent_t
));
520 list_destroy(&spa
->spa_config_list
);
522 nvlist_free(spa
->spa_load_info
);
523 spa_config_set(spa
, NULL
);
525 refcount_destroy(&spa
->spa_refcount
);
527 spa_config_lock_destroy(spa
);
529 for (int t
= 0; t
< TXG_SIZE
; t
++)
530 bplist_destroy(&spa
->spa_free_bplist
[t
]);
532 cv_destroy(&spa
->spa_async_cv
);
533 cv_destroy(&spa
->spa_proc_cv
);
534 cv_destroy(&spa
->spa_scrub_io_cv
);
535 cv_destroy(&spa
->spa_suspend_cv
);
537 mutex_destroy(&spa
->spa_async_lock
);
538 mutex_destroy(&spa
->spa_errlist_lock
);
539 mutex_destroy(&spa
->spa_errlog_lock
);
540 mutex_destroy(&spa
->spa_history_lock
);
541 mutex_destroy(&spa
->spa_proc_lock
);
542 mutex_destroy(&spa
->spa_props_lock
);
543 mutex_destroy(&spa
->spa_scrub_lock
);
544 mutex_destroy(&spa
->spa_suspend_lock
);
545 mutex_destroy(&spa
->spa_vdev_top_lock
);
547 kmem_free(spa
, sizeof (spa_t
));
551 * Given a pool, return the next pool in the namespace, or NULL if there is
552 * none. If 'prev' is NULL, return the first pool.
555 spa_next(spa_t
*prev
)
557 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
560 return (AVL_NEXT(&spa_namespace_avl
, prev
));
562 return (avl_first(&spa_namespace_avl
));
566 * ==========================================================================
567 * SPA refcount functions
568 * ==========================================================================
572 * Add a reference to the given spa_t. Must have at least one reference, or
573 * have the namespace lock held.
576 spa_open_ref(spa_t
*spa
, void *tag
)
578 ASSERT(refcount_count(&spa
->spa_refcount
) >= spa
->spa_minref
||
579 MUTEX_HELD(&spa_namespace_lock
));
580 (void) refcount_add(&spa
->spa_refcount
, tag
);
584 * Remove a reference to the given spa_t. Must have at least one reference, or
585 * have the namespace lock held.
588 spa_close(spa_t
*spa
, void *tag
)
590 ASSERT(refcount_count(&spa
->spa_refcount
) > spa
->spa_minref
||
591 MUTEX_HELD(&spa_namespace_lock
));
592 (void) refcount_remove(&spa
->spa_refcount
, tag
);
596 * Check to see if the spa refcount is zero. Must be called with
597 * spa_namespace_lock held. We really compare against spa_minref, which is the
598 * number of references acquired when opening a pool
601 spa_refcount_zero(spa_t
*spa
)
603 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
605 return (refcount_count(&spa
->spa_refcount
) == spa
->spa_minref
);
609 * ==========================================================================
610 * SPA spare and l2cache tracking
611 * ==========================================================================
615 * Hot spares and cache devices are tracked using the same code below,
616 * for 'auxiliary' devices.
619 typedef struct spa_aux
{
627 spa_aux_compare(const void *a
, const void *b
)
629 const spa_aux_t
*sa
= a
;
630 const spa_aux_t
*sb
= b
;
632 if (sa
->aux_guid
< sb
->aux_guid
)
634 else if (sa
->aux_guid
> sb
->aux_guid
)
641 spa_aux_add(vdev_t
*vd
, avl_tree_t
*avl
)
647 search
.aux_guid
= vd
->vdev_guid
;
648 if ((aux
= avl_find(avl
, &search
, &where
)) != NULL
) {
651 aux
= kmem_zalloc(sizeof (spa_aux_t
), KM_SLEEP
);
652 aux
->aux_guid
= vd
->vdev_guid
;
654 avl_insert(avl
, aux
, where
);
659 spa_aux_remove(vdev_t
*vd
, avl_tree_t
*avl
)
665 search
.aux_guid
= vd
->vdev_guid
;
666 aux
= avl_find(avl
, &search
, &where
);
670 if (--aux
->aux_count
== 0) {
671 avl_remove(avl
, aux
);
672 kmem_free(aux
, sizeof (spa_aux_t
));
673 } else if (aux
->aux_pool
== spa_guid(vd
->vdev_spa
)) {
674 aux
->aux_pool
= 0ULL;
679 spa_aux_exists(uint64_t guid
, uint64_t *pool
, int *refcnt
, avl_tree_t
*avl
)
681 spa_aux_t search
, *found
;
683 search
.aux_guid
= guid
;
684 found
= avl_find(avl
, &search
, NULL
);
688 *pool
= found
->aux_pool
;
695 *refcnt
= found
->aux_count
;
700 return (found
!= NULL
);
704 spa_aux_activate(vdev_t
*vd
, avl_tree_t
*avl
)
706 spa_aux_t search
, *found
;
709 search
.aux_guid
= vd
->vdev_guid
;
710 found
= avl_find(avl
, &search
, &where
);
711 ASSERT(found
!= NULL
);
712 ASSERT(found
->aux_pool
== 0ULL);
714 found
->aux_pool
= spa_guid(vd
->vdev_spa
);
718 * Spares are tracked globally due to the following constraints:
720 * - A spare may be part of multiple pools.
721 * - A spare may be added to a pool even if it's actively in use within
723 * - A spare in use in any pool can only be the source of a replacement if
724 * the target is a spare in the same pool.
726 * We keep track of all spares on the system through the use of a reference
727 * counted AVL tree. When a vdev is added as a spare, or used as a replacement
728 * spare, then we bump the reference count in the AVL tree. In addition, we set
729 * the 'vdev_isspare' member to indicate that the device is a spare (active or
730 * inactive). When a spare is made active (used to replace a device in the
731 * pool), we also keep track of which pool its been made a part of.
733 * The 'spa_spare_lock' protects the AVL tree. These functions are normally
734 * called under the spa_namespace lock as part of vdev reconfiguration. The
735 * separate spare lock exists for the status query path, which does not need to
736 * be completely consistent with respect to other vdev configuration changes.
740 spa_spare_compare(const void *a
, const void *b
)
742 return (spa_aux_compare(a
, b
));
746 spa_spare_add(vdev_t
*vd
)
748 mutex_enter(&spa_spare_lock
);
749 ASSERT(!vd
->vdev_isspare
);
750 spa_aux_add(vd
, &spa_spare_avl
);
751 vd
->vdev_isspare
= B_TRUE
;
752 mutex_exit(&spa_spare_lock
);
756 spa_spare_remove(vdev_t
*vd
)
758 mutex_enter(&spa_spare_lock
);
759 ASSERT(vd
->vdev_isspare
);
760 spa_aux_remove(vd
, &spa_spare_avl
);
761 vd
->vdev_isspare
= B_FALSE
;
762 mutex_exit(&spa_spare_lock
);
766 spa_spare_exists(uint64_t guid
, uint64_t *pool
, int *refcnt
)
770 mutex_enter(&spa_spare_lock
);
771 found
= spa_aux_exists(guid
, pool
, refcnt
, &spa_spare_avl
);
772 mutex_exit(&spa_spare_lock
);
778 spa_spare_activate(vdev_t
*vd
)
780 mutex_enter(&spa_spare_lock
);
781 ASSERT(vd
->vdev_isspare
);
782 spa_aux_activate(vd
, &spa_spare_avl
);
783 mutex_exit(&spa_spare_lock
);
787 * Level 2 ARC devices are tracked globally for the same reasons as spares.
788 * Cache devices currently only support one pool per cache device, and so
789 * for these devices the aux reference count is currently unused beyond 1.
793 spa_l2cache_compare(const void *a
, const void *b
)
795 return (spa_aux_compare(a
, b
));
799 spa_l2cache_add(vdev_t
*vd
)
801 mutex_enter(&spa_l2cache_lock
);
802 ASSERT(!vd
->vdev_isl2cache
);
803 spa_aux_add(vd
, &spa_l2cache_avl
);
804 vd
->vdev_isl2cache
= B_TRUE
;
805 mutex_exit(&spa_l2cache_lock
);
809 spa_l2cache_remove(vdev_t
*vd
)
811 mutex_enter(&spa_l2cache_lock
);
812 ASSERT(vd
->vdev_isl2cache
);
813 spa_aux_remove(vd
, &spa_l2cache_avl
);
814 vd
->vdev_isl2cache
= B_FALSE
;
815 mutex_exit(&spa_l2cache_lock
);
819 spa_l2cache_exists(uint64_t guid
, uint64_t *pool
)
823 mutex_enter(&spa_l2cache_lock
);
824 found
= spa_aux_exists(guid
, pool
, NULL
, &spa_l2cache_avl
);
825 mutex_exit(&spa_l2cache_lock
);
831 spa_l2cache_activate(vdev_t
*vd
)
833 mutex_enter(&spa_l2cache_lock
);
834 ASSERT(vd
->vdev_isl2cache
);
835 spa_aux_activate(vd
, &spa_l2cache_avl
);
836 mutex_exit(&spa_l2cache_lock
);
840 * ==========================================================================
842 * ==========================================================================
846 * Lock the given spa_t for the purpose of adding or removing a vdev.
847 * Grabs the global spa_namespace_lock plus the spa config lock for writing.
848 * It returns the next transaction group for the spa_t.
851 spa_vdev_enter(spa_t
*spa
)
853 mutex_enter(&spa
->spa_vdev_top_lock
);
854 mutex_enter(&spa_namespace_lock
);
855 return (spa_vdev_config_enter(spa
));
859 * Internal implementation for spa_vdev_enter(). Used when a vdev
860 * operation requires multiple syncs (i.e. removing a device) while
861 * keeping the spa_namespace_lock held.
864 spa_vdev_config_enter(spa_t
*spa
)
866 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
868 spa_config_enter(spa
, SCL_ALL
, spa
, RW_WRITER
);
870 return (spa_last_synced_txg(spa
) + 1);
874 * Used in combination with spa_vdev_config_enter() to allow the syncing
875 * of multiple transactions without releasing the spa_namespace_lock.
878 spa_vdev_config_exit(spa_t
*spa
, vdev_t
*vd
, uint64_t txg
, int error
, char *tag
)
880 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
882 int config_changed
= B_FALSE
;
884 ASSERT(txg
> spa_last_synced_txg(spa
));
886 spa
->spa_pending_vdev
= NULL
;
891 vdev_dtl_reassess(spa
->spa_root_vdev
, 0, 0, B_FALSE
);
893 if (error
== 0 && !list_is_empty(&spa
->spa_config_dirty_list
)) {
894 config_changed
= B_TRUE
;
895 spa
->spa_config_generation
++;
899 * Verify the metaslab classes.
901 ASSERT(metaslab_class_validate(spa_normal_class(spa
)) == 0);
902 ASSERT(metaslab_class_validate(spa_log_class(spa
)) == 0);
904 spa_config_exit(spa
, SCL_ALL
, spa
);
907 * Panic the system if the specified tag requires it. This
908 * is useful for ensuring that configurations are updated
911 if (zio_injection_enabled
)
912 zio_handle_panic_injection(spa
, tag
, 0);
915 * Note: this txg_wait_synced() is important because it ensures
916 * that there won't be more than one config change per txg.
917 * This allows us to use the txg as the generation number.
920 txg_wait_synced(spa
->spa_dsl_pool
, txg
);
923 ASSERT(!vd
->vdev_detached
|| vd
->vdev_dtl_smo
.smo_object
== 0);
924 spa_config_enter(spa
, SCL_ALL
, spa
, RW_WRITER
);
926 spa_config_exit(spa
, SCL_ALL
, spa
);
930 * If the config changed, update the config cache.
933 spa_config_sync(spa
, B_FALSE
, B_TRUE
);
937 * Unlock the spa_t after adding or removing a vdev. Besides undoing the
938 * locking of spa_vdev_enter(), we also want make sure the transactions have
939 * synced to disk, and then update the global configuration cache with the new
943 spa_vdev_exit(spa_t
*spa
, vdev_t
*vd
, uint64_t txg
, int error
)
945 spa_vdev_config_exit(spa
, vd
, txg
, error
, FTAG
);
946 mutex_exit(&spa_namespace_lock
);
947 mutex_exit(&spa
->spa_vdev_top_lock
);
953 * Lock the given spa_t for the purpose of changing vdev state.
956 spa_vdev_state_enter(spa_t
*spa
, int oplocks
)
958 int locks
= SCL_STATE_ALL
| oplocks
;
961 * Root pools may need to read of the underlying devfs filesystem
962 * when opening up a vdev. Unfortunately if we're holding the
963 * SCL_ZIO lock it will result in a deadlock when we try to issue
964 * the read from the root filesystem. Instead we "prefetch"
965 * the associated vnodes that we need prior to opening the
966 * underlying devices and cache them so that we can prevent
967 * any I/O when we are doing the actual open.
969 if (spa_is_root(spa
)) {
970 int low
= locks
& ~(SCL_ZIO
- 1);
971 int high
= locks
& ~low
;
973 spa_config_enter(spa
, high
, spa
, RW_WRITER
);
974 vdev_hold(spa
->spa_root_vdev
);
975 spa_config_enter(spa
, low
, spa
, RW_WRITER
);
977 spa_config_enter(spa
, locks
, spa
, RW_WRITER
);
979 spa
->spa_vdev_locks
= locks
;
983 spa_vdev_state_exit(spa_t
*spa
, vdev_t
*vd
, int error
)
985 boolean_t config_changed
= B_FALSE
;
987 if (vd
!= NULL
|| error
== 0)
988 vdev_dtl_reassess(vd
? vd
->vdev_top
: spa
->spa_root_vdev
,
992 vdev_state_dirty(vd
->vdev_top
);
993 config_changed
= B_TRUE
;
994 spa
->spa_config_generation
++;
997 if (spa_is_root(spa
))
998 vdev_rele(spa
->spa_root_vdev
);
1000 ASSERT3U(spa
->spa_vdev_locks
, >=, SCL_STATE_ALL
);
1001 spa_config_exit(spa
, spa
->spa_vdev_locks
, spa
);
1004 * If anything changed, wait for it to sync. This ensures that,
1005 * from the system administrator's perspective, zpool(1M) commands
1006 * are synchronous. This is important for things like zpool offline:
1007 * when the command completes, you expect no further I/O from ZFS.
1010 txg_wait_synced(spa
->spa_dsl_pool
, 0);
1013 * If the config changed, update the config cache.
1015 if (config_changed
) {
1016 mutex_enter(&spa_namespace_lock
);
1017 spa_config_sync(spa
, B_FALSE
, B_TRUE
);
1018 mutex_exit(&spa_namespace_lock
);
1025 * ==========================================================================
1026 * Miscellaneous functions
1027 * ==========================================================================
1034 spa_rename(const char *name
, const char *newname
)
1040 * Lookup the spa_t and grab the config lock for writing. We need to
1041 * actually open the pool so that we can sync out the necessary labels.
1042 * It's OK to call spa_open() with the namespace lock held because we
1043 * allow recursive calls for other reasons.
1045 mutex_enter(&spa_namespace_lock
);
1046 if ((err
= spa_open(name
, &spa
, FTAG
)) != 0) {
1047 mutex_exit(&spa_namespace_lock
);
1051 spa_config_enter(spa
, SCL_ALL
, FTAG
, RW_WRITER
);
1053 avl_remove(&spa_namespace_avl
, spa
);
1054 (void) strlcpy(spa
->spa_name
, newname
, sizeof (spa
->spa_name
));
1055 avl_add(&spa_namespace_avl
, spa
);
1058 * Sync all labels to disk with the new names by marking the root vdev
1059 * dirty and waiting for it to sync. It will pick up the new pool name
1062 vdev_config_dirty(spa
->spa_root_vdev
);
1064 spa_config_exit(spa
, SCL_ALL
, FTAG
);
1066 txg_wait_synced(spa
->spa_dsl_pool
, 0);
1069 * Sync the updated config cache.
1071 spa_config_sync(spa
, B_FALSE
, B_TRUE
);
1073 spa_close(spa
, FTAG
);
1075 mutex_exit(&spa_namespace_lock
);
1081 * Return the spa_t associated with given pool_guid, if it exists. If
1082 * device_guid is non-zero, determine whether the pool exists *and* contains
1083 * a device with the specified device_guid.
1086 spa_by_guid(uint64_t pool_guid
, uint64_t device_guid
)
1089 avl_tree_t
*t
= &spa_namespace_avl
;
1091 ASSERT(MUTEX_HELD(&spa_namespace_lock
));
1093 for (spa
= avl_first(t
); spa
!= NULL
; spa
= AVL_NEXT(t
, spa
)) {
1094 if (spa
->spa_state
== POOL_STATE_UNINITIALIZED
)
1096 if (spa
->spa_root_vdev
== NULL
)
1098 if (spa_guid(spa
) == pool_guid
) {
1099 if (device_guid
== 0)
1102 if (vdev_lookup_by_guid(spa
->spa_root_vdev
,
1103 device_guid
) != NULL
)
1107 * Check any devices we may be in the process of adding.
1109 if (spa
->spa_pending_vdev
) {
1110 if (vdev_lookup_by_guid(spa
->spa_pending_vdev
,
1111 device_guid
) != NULL
)
1121 * Determine whether a pool with the given pool_guid exists.
1124 spa_guid_exists(uint64_t pool_guid
, uint64_t device_guid
)
1126 return (spa_by_guid(pool_guid
, device_guid
) != NULL
);
1130 spa_strdup(const char *s
)
1136 new = kmem_alloc(len
+ 1, KM_SLEEP
);
1144 spa_strfree(char *s
)
1146 kmem_free(s
, strlen(s
) + 1);
1150 spa_get_random(uint64_t range
)
1156 (void) random_get_pseudo_bytes((void *)&r
, sizeof (uint64_t));
1162 spa_generate_guid(spa_t
*spa
)
1164 uint64_t guid
= spa_get_random(-1ULL);
1167 while (guid
== 0 || spa_guid_exists(spa_guid(spa
), guid
))
1168 guid
= spa_get_random(-1ULL);
1170 while (guid
== 0 || spa_guid_exists(guid
, 0))
1171 guid
= spa_get_random(-1ULL);
1178 sprintf_blkptr(char *buf
, const blkptr_t
*bp
)
1181 char *checksum
= NULL
;
1182 char *compress
= NULL
;
1185 type
= dmu_ot
[BP_GET_TYPE(bp
)].ot_name
;
1186 checksum
= zio_checksum_table
[BP_GET_CHECKSUM(bp
)].ci_name
;
1187 compress
= zio_compress_table
[BP_GET_COMPRESS(bp
)].ci_name
;
1190 SPRINTF_BLKPTR(snprintf
, ' ', buf
, bp
, type
, checksum
, compress
);
1194 spa_freeze(spa_t
*spa
)
1196 uint64_t freeze_txg
= 0;
1198 spa_config_enter(spa
, SCL_ALL
, FTAG
, RW_WRITER
);
1199 if (spa
->spa_freeze_txg
== UINT64_MAX
) {
1200 freeze_txg
= spa_last_synced_txg(spa
) + TXG_SIZE
;
1201 spa
->spa_freeze_txg
= freeze_txg
;
1203 spa_config_exit(spa
, SCL_ALL
, FTAG
);
1204 if (freeze_txg
!= 0)
1205 txg_wait_synced(spa_get_dsl(spa
), freeze_txg
);
1209 zfs_panic_recover(const char *fmt
, ...)
1214 vcmn_err(zfs_recover
? CE_WARN
: CE_PANIC
, fmt
, adx
);
1219 * This is a stripped-down version of strtoull, suitable only for converting
1220 * lowercase hexidecimal numbers that don't overflow.
1223 strtonum(const char *str
, char **nptr
)
1229 while ((c
= *str
) != '\0') {
1230 if (c
>= '0' && c
<= '9')
1232 else if (c
>= 'a' && c
<= 'f')
1233 digit
= 10 + c
- 'a';
1244 *nptr
= (char *)str
;
1250 * ==========================================================================
1251 * Accessor functions
1252 * ==========================================================================
1256 spa_shutting_down(spa_t
*spa
)
1258 return (spa
->spa_async_suspended
);
1262 spa_get_dsl(spa_t
*spa
)
1264 return (spa
->spa_dsl_pool
);
1268 spa_get_rootblkptr(spa_t
*spa
)
1270 return (&spa
->spa_ubsync
.ub_rootbp
);
1274 spa_set_rootblkptr(spa_t
*spa
, const blkptr_t
*bp
)
1276 spa
->spa_uberblock
.ub_rootbp
= *bp
;
1280 spa_altroot(spa_t
*spa
, char *buf
, size_t buflen
)
1282 if (spa
->spa_root
== NULL
)
1285 (void) strncpy(buf
, spa
->spa_root
, buflen
);
1289 spa_sync_pass(spa_t
*spa
)
1291 return (spa
->spa_sync_pass
);
1295 spa_name(spa_t
*spa
)
1297 return (spa
->spa_name
);
1301 spa_guid(spa_t
*spa
)
1304 * If we fail to parse the config during spa_load(), we can go through
1305 * the error path (which posts an ereport) and end up here with no root
1306 * vdev. We stash the original pool guid in 'spa_load_guid' to handle
1309 if (spa
->spa_root_vdev
!= NULL
)
1310 return (spa
->spa_root_vdev
->vdev_guid
);
1312 return (spa
->spa_load_guid
);
1316 spa_last_synced_txg(spa_t
*spa
)
1318 return (spa
->spa_ubsync
.ub_txg
);
1322 spa_first_txg(spa_t
*spa
)
1324 return (spa
->spa_first_txg
);
1328 spa_syncing_txg(spa_t
*spa
)
1330 return (spa
->spa_syncing_txg
);
1334 spa_state(spa_t
*spa
)
1336 return (spa
->spa_state
);
1340 spa_load_state(spa_t
*spa
)
1342 return (spa
->spa_load_state
);
1346 spa_freeze_txg(spa_t
*spa
)
1348 return (spa
->spa_freeze_txg
);
1353 spa_get_asize(spa_t
*spa
, uint64_t lsize
)
1356 * The worst case is single-sector max-parity RAID-Z blocks, in which
1357 * case the space requirement is exactly (VDEV_RAIDZ_MAXPARITY + 1)
1358 * times the size; so just assume that. Add to this the fact that
1359 * we can have up to 3 DVAs per bp, and one more factor of 2 because
1360 * the block may be dittoed with up to 3 DVAs by ddt_sync().
1362 return (lsize
* (VDEV_RAIDZ_MAXPARITY
+ 1) * SPA_DVAS_PER_BP
* 2);
1366 spa_get_dspace(spa_t
*spa
)
1368 return (spa
->spa_dspace
);
1372 spa_update_dspace(spa_t
*spa
)
1374 spa
->spa_dspace
= metaslab_class_get_dspace(spa_normal_class(spa
)) +
1375 ddt_get_dedup_dspace(spa
);
1379 * Return the failure mode that has been set to this pool. The default
1380 * behavior will be to block all I/Os when a complete failure occurs.
1383 spa_get_failmode(spa_t
*spa
)
1385 return (spa
->spa_failmode
);
1389 spa_suspended(spa_t
*spa
)
1391 return (spa
->spa_suspended
);
1395 spa_version(spa_t
*spa
)
1397 return (spa
->spa_ubsync
.ub_version
);
1401 spa_deflate(spa_t
*spa
)
1403 return (spa
->spa_deflate
);
1407 spa_normal_class(spa_t
*spa
)
1409 return (spa
->spa_normal_class
);
1413 spa_log_class(spa_t
*spa
)
1415 return (spa
->spa_log_class
);
1419 spa_max_replication(spa_t
*spa
)
1422 * As of SPA_VERSION == SPA_VERSION_DITTO_BLOCKS, we are able to
1423 * handle BPs with more than one DVA allocated. Set our max
1424 * replication level accordingly.
1426 if (spa_version(spa
) < SPA_VERSION_DITTO_BLOCKS
)
1428 return (MIN(SPA_DVAS_PER_BP
, spa_max_replication_override
));
1432 spa_prev_software_version(spa_t
*spa
)
1434 return (spa
->spa_prev_software_version
);
1438 dva_get_dsize_sync(spa_t
*spa
, const dva_t
*dva
)
1440 uint64_t asize
= DVA_GET_ASIZE(dva
);
1441 uint64_t dsize
= asize
;
1443 ASSERT(spa_config_held(spa
, SCL_ALL
, RW_READER
) != 0);
1445 if (asize
!= 0 && spa
->spa_deflate
) {
1446 vdev_t
*vd
= vdev_lookup_top(spa
, DVA_GET_VDEV(dva
));
1447 dsize
= (asize
>> SPA_MINBLOCKSHIFT
) * vd
->vdev_deflate_ratio
;
1454 bp_get_dsize_sync(spa_t
*spa
, const blkptr_t
*bp
)
1458 for (int d
= 0; d
< SPA_DVAS_PER_BP
; d
++)
1459 dsize
+= dva_get_dsize_sync(spa
, &bp
->blk_dva
[d
]);
1465 bp_get_dsize(spa_t
*spa
, const blkptr_t
*bp
)
1469 spa_config_enter(spa
, SCL_VDEV
, FTAG
, RW_READER
);
1471 for (int d
= 0; d
< SPA_DVAS_PER_BP
; d
++)
1472 dsize
+= dva_get_dsize_sync(spa
, &bp
->blk_dva
[d
]);
1474 spa_config_exit(spa
, SCL_VDEV
, FTAG
);
1480 * ==========================================================================
1481 * Initialization and Termination
1482 * ==========================================================================
1486 spa_name_compare(const void *a1
, const void *a2
)
1488 const spa_t
*s1
= a1
;
1489 const spa_t
*s2
= a2
;
1492 s
= strcmp(s1
->spa_name
, s2
->spa_name
);
1503 return (spa_active_count
);
1515 mutex_init(&spa_namespace_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
1516 mutex_init(&spa_spare_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
1517 mutex_init(&spa_l2cache_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
1518 cv_init(&spa_namespace_cv
, NULL
, CV_DEFAULT
, NULL
);
1520 avl_create(&spa_namespace_avl
, spa_name_compare
, sizeof (spa_t
),
1521 offsetof(spa_t
, spa_avl
));
1523 avl_create(&spa_spare_avl
, spa_spare_compare
, sizeof (spa_aux_t
),
1524 offsetof(spa_aux_t
, aux_avl
));
1526 avl_create(&spa_l2cache_avl
, spa_l2cache_compare
, sizeof (spa_aux_t
),
1527 offsetof(spa_aux_t
, aux_avl
));
1529 spa_mode_global
= mode
;
1536 vdev_cache_stat_init();
1550 vdev_cache_stat_fini();
1557 avl_destroy(&spa_namespace_avl
);
1558 avl_destroy(&spa_spare_avl
);
1559 avl_destroy(&spa_l2cache_avl
);
1561 cv_destroy(&spa_namespace_cv
);
1562 mutex_destroy(&spa_namespace_lock
);
1563 mutex_destroy(&spa_spare_lock
);
1564 mutex_destroy(&spa_l2cache_lock
);
1568 * Return whether this pool has slogs. No locking needed.
1569 * It's not a problem if the wrong answer is returned as it's only for
1570 * performance and not correctness
1573 spa_has_slogs(spa_t
*spa
)
1575 return (spa
->spa_log_class
->mc_rotor
!= NULL
);
1579 spa_get_log_state(spa_t
*spa
)
1581 return (spa
->spa_log_state
);
1585 spa_set_log_state(spa_t
*spa
, spa_log_state_t state
)
1587 spa
->spa_log_state
= state
;
1591 spa_is_root(spa_t
*spa
)
1593 return (spa
->spa_is_root
);
1597 spa_writeable(spa_t
*spa
)
1599 return (!!(spa
->spa_mode
& FWRITE
));
1603 spa_mode(spa_t
*spa
)
1605 return (spa
->spa_mode
);
1609 spa_bootfs(spa_t
*spa
)
1611 return (spa
->spa_bootfs
);
1615 spa_delegation(spa_t
*spa
)
1617 return (spa
->spa_delegation
);
1621 spa_meta_objset(spa_t
*spa
)
1623 return (spa
->spa_meta_objset
);
1627 spa_dedup_checksum(spa_t
*spa
)
1629 return (spa
->spa_dedup_checksum
);
1633 * Reset pool scan stat per scan pass (or reboot).
1636 spa_scan_stat_init(spa_t
*spa
)
1638 /* data not stored on disk */
1639 spa
->spa_scan_pass_start
= gethrestime_sec();
1640 spa
->spa_scan_pass_exam
= 0;
1641 vdev_scan_stat_init(spa
->spa_root_vdev
);
1645 * Get scan stats for zpool status reports
1648 spa_scan_get_stats(spa_t
*spa
, pool_scan_stat_t
*ps
)
1650 dsl_scan_t
*scn
= spa
->spa_dsl_pool
? spa
->spa_dsl_pool
->dp_scan
: NULL
;
1652 if (scn
== NULL
|| scn
->scn_phys
.scn_func
== POOL_SCAN_NONE
)
1654 bzero(ps
, sizeof (pool_scan_stat_t
));
1656 /* data stored on disk */
1657 ps
->pss_func
= scn
->scn_phys
.scn_func
;
1658 ps
->pss_start_time
= scn
->scn_phys
.scn_start_time
;
1659 ps
->pss_end_time
= scn
->scn_phys
.scn_end_time
;
1660 ps
->pss_to_examine
= scn
->scn_phys
.scn_to_examine
;
1661 ps
->pss_examined
= scn
->scn_phys
.scn_examined
;
1662 ps
->pss_to_process
= scn
->scn_phys
.scn_to_process
;
1663 ps
->pss_processed
= scn
->scn_phys
.scn_processed
;
1664 ps
->pss_errors
= scn
->scn_phys
.scn_errors
;
1665 ps
->pss_state
= scn
->scn_phys
.scn_state
;
1667 /* data not stored on disk */
1668 ps
->pss_pass_start
= spa
->spa_scan_pass_start
;
1669 ps
->pss_pass_exam
= spa
->spa_scan_pass_exam
;