6280668 pluggable block allocation policy
6399301 initial read of space maps is super slow
6407365 large-sector disk support in ZFS
6407366 ADVANCE_NOLOCK gathers MOS
6407367 three-way deadlock between db_mtx, dbuf_hash[], and ms_lock
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* This file contains all the routines used when modifying on-disk SPA state.
* This includes opening, importing, destroying, exporting a pool, and syncing a
* pool.
*/
#include <sys/zfs_context.h>
#include <sys/fm/fs/zfs.h>
#include <sys/spa_impl.h>
#include <sys/zio.h>
#include <sys/zio_checksum.h>
#include <sys/zio_compress.h>
#include <sys/dmu.h>
#include <sys/dmu_tx.h>
#include <sys/zap.h>
#include <sys/zil.h>
#include <sys/vdev_impl.h>
#include <sys/metaslab.h>
#include <sys/uberblock_impl.h>
#include <sys/txg.h>
#include <sys/avl.h>
#include <sys/dmu_traverse.h>
#include <sys/unique.h>
#include <sys/dsl_pool.h>
#include <sys/dsl_dir.h>
#include <sys/dsl_prop.h>
#include <sys/fs/zfs.h>
#include <sys/callb.h>
/*
* ==========================================================================
* SPA state manipulation (open/create/destroy/import/export)
* ==========================================================================
*/
static int
spa_error_entry_compare(const void *a, const void *b)
{
spa_error_entry_t *sa = (spa_error_entry_t *)a;
spa_error_entry_t *sb = (spa_error_entry_t *)b;
int ret;
ret = bcmp(&sa->se_bookmark, &sb->se_bookmark,
sizeof (zbookmark_t));
if (ret < 0)
return (-1);
else if (ret > 0)
return (1);
else
return (0);
}
/*
* Utility function which retrieves copies of the current logs and
* re-initializes them in the process.
*/
void
spa_get_errlists(spa_t *spa, avl_tree_t *last, avl_tree_t *scrub)
{
ASSERT(MUTEX_HELD(&spa->spa_errlist_lock));
bcopy(&spa->spa_errlist_last, last, sizeof (avl_tree_t));
bcopy(&spa->spa_errlist_scrub, scrub, sizeof (avl_tree_t));
avl_create(&spa->spa_errlist_scrub,
spa_error_entry_compare, sizeof (spa_error_entry_t),
offsetof(spa_error_entry_t, se_avl));
avl_create(&spa->spa_errlist_last,
spa_error_entry_compare, sizeof (spa_error_entry_t),
offsetof(spa_error_entry_t, se_avl));
}
/*
* Activate an uninitialized pool.
*/
static void
spa_activate(spa_t *spa)
{
int t;
ASSERT(spa->spa_state == POOL_STATE_UNINITIALIZED);
spa->spa_state = POOL_STATE_ACTIVE;
spa->spa_normal_class = metaslab_class_create();
for (t = 0; t < ZIO_TYPES; t++) {
spa->spa_zio_issue_taskq[t] = taskq_create("spa_zio_issue",
8, maxclsyspri, 50, INT_MAX,
TASKQ_PREPOPULATE);
spa->spa_zio_intr_taskq[t] = taskq_create("spa_zio_intr",
8, maxclsyspri, 50, INT_MAX,
TASKQ_PREPOPULATE);
}
rw_init(&spa->spa_traverse_lock, NULL, RW_DEFAULT, NULL);
list_create(&spa->spa_dirty_list, sizeof (vdev_t),
offsetof(vdev_t, vdev_dirty_node));
txg_list_create(&spa->spa_vdev_txg_list,
offsetof(struct vdev, vdev_txg_node));
avl_create(&spa->spa_errlist_scrub,
spa_error_entry_compare, sizeof (spa_error_entry_t),
offsetof(spa_error_entry_t, se_avl));
avl_create(&spa->spa_errlist_last,
spa_error_entry_compare, sizeof (spa_error_entry_t),
offsetof(spa_error_entry_t, se_avl));
}
/*
* Opposite of spa_activate().
*/
static void
spa_deactivate(spa_t *spa)
{
int t;
ASSERT(spa->spa_sync_on == B_FALSE);
ASSERT(spa->spa_dsl_pool == NULL);
ASSERT(spa->spa_root_vdev == NULL);
ASSERT(spa->spa_state != POOL_STATE_UNINITIALIZED);
txg_list_destroy(&spa->spa_vdev_txg_list);
list_destroy(&spa->spa_dirty_list);
rw_destroy(&spa->spa_traverse_lock);
for (t = 0; t < ZIO_TYPES; t++) {
taskq_destroy(spa->spa_zio_issue_taskq[t]);
taskq_destroy(spa->spa_zio_intr_taskq[t]);
spa->spa_zio_issue_taskq[t] = NULL;
spa->spa_zio_intr_taskq[t] = NULL;
}
metaslab_class_destroy(spa->spa_normal_class);
spa->spa_normal_class = NULL;
/*
* If this was part of an import or the open otherwise failed, we may
* still have errors left in the queues. Empty them just in case.
*/
spa_errlog_drain(spa);
avl_destroy(&spa->spa_errlist_scrub);
avl_destroy(&spa->spa_errlist_last);
spa->spa_state = POOL_STATE_UNINITIALIZED;
}
/*
* Verify a pool configuration, and construct the vdev tree appropriately. This
* will create all the necessary vdevs in the appropriate layout, with each vdev
* in the CLOSED state. This will prep the pool before open/creation/import.
* All vdev validation is done by the vdev_alloc() routine.
*/
static vdev_t *
spa_config_parse(spa_t *spa, nvlist_t *nv, vdev_t *parent, uint_t id, int atype)
{
nvlist_t **child;
uint_t c, children;
vdev_t *vd;
if ((vd = vdev_alloc(spa, nv, parent, id, atype)) == NULL)
return (NULL);
if (vd->vdev_ops->vdev_op_leaf)
return (vd);
if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
&child, &children) != 0) {
vdev_free(vd);
return (NULL);
}
for (c = 0; c < children; c++) {
if (spa_config_parse(spa, child[c], vd, c, atype) == NULL) {
vdev_free(vd);
return (NULL);
}
}
return (vd);
}
/*
* Opposite of spa_load().
*/
static void
spa_unload(spa_t *spa)
{
/*
* Stop async tasks.
*/
spa_async_suspend(spa);
/*
* Stop syncing.
*/
if (spa->spa_sync_on) {
txg_sync_stop(spa->spa_dsl_pool);
spa->spa_sync_on = B_FALSE;
}
/*
* Wait for any outstanding prefetch I/O to complete.
*/
spa_config_enter(spa, RW_WRITER, FTAG);
spa_config_exit(spa, FTAG);
/*
* Close the dsl pool.
*/
if (spa->spa_dsl_pool) {
dsl_pool_close(spa->spa_dsl_pool);
spa->spa_dsl_pool = NULL;
}
/*
* Close all vdevs.
*/
if (spa->spa_root_vdev)
vdev_free(spa->spa_root_vdev);
ASSERT(spa->spa_root_vdev == NULL);
spa->spa_async_suspended = 0;
}
/*
* Load an existing storage pool, using the pool's builtin spa_config as a
* source of configuration information.
*/
static int
spa_load(spa_t *spa, nvlist_t *config, spa_load_state_t state, int mosconfig)
{
int error = 0;
nvlist_t *nvroot = NULL;
vdev_t *rvd;
uberblock_t *ub = &spa->spa_uberblock;
uint64_t config_cache_txg = spa->spa_config_txg;
uint64_t pool_guid;
zio_t *zio;
spa->spa_load_state = state;
if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nvroot) ||
nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID, &pool_guid) ||
(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
&spa->spa_config_txg) && mosconfig)) {
error = EINVAL;
goto out;
}
if ((state == SPA_LOAD_IMPORT || state == SPA_LOAD_TRYIMPORT) &&
spa_guid_exists(pool_guid, 0)) {
error = EEXIST;
goto out;
}
/*
* Parse the configuration into a vdev tree.
*/
spa_config_enter(spa, RW_WRITER, FTAG);
rvd = spa_config_parse(spa, nvroot, NULL, 0, VDEV_ALLOC_LOAD);
spa_config_exit(spa, FTAG);
if (rvd == NULL) {
error = EINVAL;
goto out;
}
ASSERT(spa->spa_root_vdev == rvd);
ASSERT(spa_guid(spa) == pool_guid);
/*
* Try to open all vdevs, loading each label in the process.
*/
if (vdev_open(rvd) != 0) {
error = ENXIO;
goto out;
}
/*
* Find the best uberblock.
*/
bzero(ub, sizeof (uberblock_t));
zio = zio_root(spa, NULL, NULL,
ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE);
vdev_uberblock_load(zio, rvd, ub);
error = zio_wait(zio);
/*
* If we weren't able to find a single valid uberblock, return failure.
*/
if (ub->ub_txg == 0) {
error = ENXIO;
goto out;
}
/*
* If the pool is newer than the code, we can't open it.
*/
if (ub->ub_version > UBERBLOCK_VERSION) {
error = ENOTSUP;
goto out;
}
/*
* If the vdev guid sum doesn't match the uberblock, we have an
* incomplete configuration.
*/
if (rvd->vdev_guid_sum != ub->ub_guid_sum && mosconfig) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_BAD_GUID_SUM);
error = ENXIO;
goto out;
}
/*
* Initialize internal SPA structures.
*/
spa->spa_state = POOL_STATE_ACTIVE;
spa->spa_ubsync = spa->spa_uberblock;
spa->spa_first_txg = spa_last_synced_txg(spa) + 1;
error = dsl_pool_open(spa, spa->spa_first_txg, &spa->spa_dsl_pool);
if (error) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_CORRUPT_DATA);
goto out;
}
spa->spa_meta_objset = spa->spa_dsl_pool->dp_meta_objset;
if (zap_lookup(spa->spa_meta_objset,
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CONFIG,
sizeof (uint64_t), 1, &spa->spa_config_object) != 0) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_CORRUPT_DATA);
error = EIO;
goto out;
}
if (!mosconfig) {
dmu_buf_t *db;
char *packed = NULL;
size_t nvsize = 0;
nvlist_t *newconfig = NULL;
VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset,
spa->spa_config_object, FTAG, &db));
nvsize = *(uint64_t *)db->db_data;
dmu_buf_rele(db, FTAG);
packed = kmem_alloc(nvsize, KM_SLEEP);
error = dmu_read(spa->spa_meta_objset,
spa->spa_config_object, 0, nvsize, packed);
if (error == 0)
error = nvlist_unpack(packed, nvsize, &newconfig, 0);
kmem_free(packed, nvsize);
if (error) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_CORRUPT_DATA);
error = EIO;
goto out;
}
spa_config_set(spa, newconfig);
spa_unload(spa);
spa_deactivate(spa);
spa_activate(spa);
return (spa_load(spa, newconfig, state, B_TRUE));
}
if (zap_lookup(spa->spa_meta_objset,
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_SYNC_BPLIST,
sizeof (uint64_t), 1, &spa->spa_sync_bplist_obj) != 0) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_CORRUPT_DATA);
error = EIO;
goto out;
}
/*
* Load the persistent error log. If we have an older pool, this will
* not be present.
*/
error = zap_lookup(spa->spa_meta_objset,
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ERRLOG_LAST,
sizeof (uint64_t), 1, &spa->spa_errlog_last);
if (error != 0 &&error != ENOENT) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_CORRUPT_DATA);
error = EIO;
goto out;
}
error = zap_lookup(spa->spa_meta_objset,
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ERRLOG_SCRUB,
sizeof (uint64_t), 1, &spa->spa_errlog_scrub);
if (error != 0 && error != ENOENT) {
vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
VDEV_AUX_CORRUPT_DATA);
error = EIO;
goto out;
}
/*
* Load the vdev state for all top level vdevs. We need to grab the
* config lock because all label I/O is done with the
* ZIO_FLAG_CONFIG_HELD flag.
*/
spa_config_enter(spa, RW_READER, FTAG);
error = vdev_load(rvd);
spa_config_exit(spa, FTAG);
if (error)
goto out;
/*
* Propagate the leaf DTLs we just loaded all the way up the tree.
*/
spa_config_enter(spa, RW_WRITER, FTAG);
vdev_dtl_reassess(rvd, 0, 0, B_FALSE);
spa_config_exit(spa, FTAG);
/*
* Check the state of the root vdev. If it can't be opened, it
* indicates one or more toplevel vdevs are faulted.
*/
if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN) {
error = ENXIO;
goto out;
}
if ((spa_mode & FWRITE) && state != SPA_LOAD_TRYIMPORT) {
dmu_tx_t *tx;
int need_update = B_FALSE;
int c;
/*
* Claim log blocks that haven't been committed yet.
* This must all happen in a single txg.
*/
tx = dmu_tx_create_assigned(spa_get_dsl(spa),
spa_first_txg(spa));
dmu_objset_find(spa->spa_name, zil_claim, tx, 0);
dmu_tx_commit(tx);
spa->spa_sync_on = B_TRUE;
txg_sync_start(spa->spa_dsl_pool);
/*
* Wait for all claims to sync.
*/
txg_wait_synced(spa->spa_dsl_pool, 0);
/*
* If the config cache is stale, or we have uninitialized
* metaslabs (see spa_vdev_add()), then update the config.
*/
if (config_cache_txg != spa->spa_config_txg ||
state == SPA_LOAD_IMPORT)
need_update = B_TRUE;
for (c = 0; c < rvd->vdev_children; c++)
if (rvd->vdev_child[c]->vdev_ms_array == 0)
need_update = B_TRUE;
/*
* Update the config cache asychronously in case we're the
* root pool, in which case the config cache isn't writable yet.
*/
if (need_update)
spa_async_request(spa, SPA_ASYNC_CONFIG_UPDATE);
}
error = 0;
out:
if (error)
zfs_ereport_post(FM_EREPORT_ZFS_POOL, spa, NULL, NULL, 0, 0);
spa->spa_load_state = SPA_LOAD_NONE;
spa->spa_ena = 0;
return (error);
}
/*
* Pool Open/Import
*
* The import case is identical to an open except that the configuration is sent
* down from userland, instead of grabbed from the configuration cache. For the
* case of an open, the pool configuration will exist in the
* POOL_STATE_UNITIALIZED state.
*
* The stats information (gen/count/ustats) is used to gather vdev statistics at
* the same time open the pool, without having to keep around the spa_t in some
* ambiguous state.
*/
static int
spa_open_common(const char *pool, spa_t **spapp, void *tag, nvlist_t **config)
{
spa_t *spa;
int error;
int loaded = B_FALSE;
int locked = B_FALSE;
*spapp = NULL;
/*
* As disgusting as this is, we need to support recursive calls to this
* function because dsl_dir_open() is called during spa_load(), and ends
* up calling spa_open() again. The real fix is to figure out how to
* avoid dsl_dir_open() calling this in the first place.
*/
if (mutex_owner(&spa_namespace_lock) != curthread) {
mutex_enter(&spa_namespace_lock);
locked = B_TRUE;
}
if ((spa = spa_lookup(pool)) == NULL) {
if (locked)
mutex_exit(&spa_namespace_lock);
return (ENOENT);
}
if (spa->spa_state == POOL_STATE_UNINITIALIZED) {
spa_activate(spa);
error = spa_load(spa, spa->spa_config, SPA_LOAD_OPEN, B_FALSE);
if (error == EBADF) {
/*
* If vdev_load() returns EBADF, it indicates that one
* of the vdevs indicates that the pool has been
* exported or destroyed. If this is the case, the
* config cache is out of sync and we should remove the
* pool from the namespace.
*/
spa_unload(spa);
spa_deactivate(spa);
spa_remove(spa);
spa_config_sync();
if (locked)
mutex_exit(&spa_namespace_lock);
return (ENOENT);
}
if (error) {
/*
* We can't open the pool, but we still have useful
* information: the state of each vdev after the
* attempted vdev_open(). Return this to the user.
*/
if (config != NULL && spa->spa_root_vdev != NULL) {
spa_config_enter(spa, RW_READER, FTAG);
*config = spa_config_generate(spa, NULL, -1ULL,
B_TRUE);
spa_config_exit(spa, FTAG);
}
spa_unload(spa);
spa_deactivate(spa);
spa->spa_last_open_failed = B_TRUE;
if (locked)
mutex_exit(&spa_namespace_lock);
*spapp = NULL;
return (error);
} else {
zfs_post_ok(spa, NULL);
spa->spa_last_open_failed = B_FALSE;
}
loaded = B_TRUE;
}
spa_open_ref(spa, tag);
if (locked)
mutex_exit(&spa_namespace_lock);
*spapp = spa;
if (config != NULL) {
spa_config_enter(spa, RW_READER, FTAG);
*config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
spa_config_exit(spa, FTAG);
}
/*
* If we just loaded the pool, resilver anything that's out of date.
*/
if (loaded && (spa_mode & FWRITE))
VERIFY(spa_scrub(spa, POOL_SCRUB_RESILVER, B_TRUE) == 0);
return (0);
}
int
spa_open(const char *name, spa_t **spapp, void *tag)
{
return (spa_open_common(name, spapp, tag, NULL));
}
/*
* Lookup the given spa_t, incrementing the inject count in the process,
* preventing it from being exported or destroyed.
*/
spa_t *
spa_inject_addref(char *name)
{
spa_t *spa;
mutex_enter(&spa_namespace_lock);
if ((spa = spa_lookup(name)) == NULL) {
mutex_exit(&spa_namespace_lock);
return (NULL);
}
spa->spa_inject_ref++;
mutex_exit(&spa_namespace_lock);
return (spa);
}
void
spa_inject_delref(spa_t *spa)
{
mutex_enter(&spa_namespace_lock);
spa->spa_inject_ref--;
mutex_exit(&spa_namespace_lock);
}
int
spa_get_stats(const char *name, nvlist_t **config, char *altroot, size_t buflen)
{
int error;
spa_t *spa;
*config = NULL;
error = spa_open_common(name, &spa, FTAG, config);
if (spa && *config != NULL)
VERIFY(nvlist_add_uint64(*config, ZPOOL_CONFIG_ERRCOUNT,
spa_get_errlog_size(spa)) == 0);
/*
* We want to get the alternate root even for faulted pools, so we cheat
* and call spa_lookup() directly.
*/
if (altroot) {
if (spa == NULL) {
mutex_enter(&spa_namespace_lock);
spa = spa_lookup(name);
if (spa)
spa_altroot(spa, altroot, buflen);
else
altroot[0] = '\0';
spa = NULL;
mutex_exit(&spa_namespace_lock);
} else {
spa_altroot(spa, altroot, buflen);
}
}
if (spa != NULL)
spa_close(spa, FTAG);
return (error);
}
/*
* Pool Creation
*/
int
spa_create(const char *pool, nvlist_t *nvroot, const char *altroot)
{
spa_t *spa;
vdev_t *rvd;
dsl_pool_t *dp;
dmu_tx_t *tx;
int c, error;
uint64_t txg = TXG_INITIAL;
/*
* If this pool already exists, return failure.
*/
mutex_enter(&spa_namespace_lock);
if (spa_lookup(pool) != NULL) {
mutex_exit(&spa_namespace_lock);
return (EEXIST);
}
/*
* Allocate a new spa_t structure.
*/
spa = spa_add(pool, altroot);
spa_activate(spa);
spa->spa_uberblock.ub_txg = txg - 1;
spa->spa_ubsync = spa->spa_uberblock;
/*
* Create the root vdev.
*/
spa_config_enter(spa, RW_WRITER, FTAG);
rvd = spa_config_parse(spa, nvroot, NULL, 0, VDEV_ALLOC_ADD);
ASSERT(spa->spa_root_vdev == rvd);
if (rvd == NULL) {
error = EINVAL;
} else {
if ((error = vdev_create(rvd, txg)) == 0) {
for (c = 0; c < rvd->vdev_children; c++)
vdev_init(rvd->vdev_child[c], txg);
vdev_config_dirty(rvd);
}
}
spa_config_exit(spa, FTAG);
if (error) {
spa_unload(spa);
spa_deactivate(spa);
spa_remove(spa);
mutex_exit(&spa_namespace_lock);
return (error);
}
spa->spa_dsl_pool = dp = dsl_pool_create(spa, txg);
spa->spa_meta_objset = dp->dp_meta_objset;
tx = dmu_tx_create_assigned(dp, txg);
/*
* Create the pool config object.
*/
spa->spa_config_object = dmu_object_alloc(spa->spa_meta_objset,
DMU_OT_PACKED_NVLIST, 1 << 14,
DMU_OT_PACKED_NVLIST_SIZE, sizeof (uint64_t), tx);
if (zap_add(spa->spa_meta_objset,
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CONFIG,
sizeof (uint64_t), 1, &spa->spa_config_object, tx) != 0) {
cmn_err(CE_PANIC, "failed to add pool config");
}
/*
* Create the deferred-free bplist object. Turn off compression
* because sync-to-convergence takes longer if the blocksize
* keeps changing.
*/
spa->spa_sync_bplist_obj = bplist_create(spa->spa_meta_objset,
1 << 14, tx);
dmu_object_set_compress(spa->spa_meta_objset, spa->spa_sync_bplist_obj,
ZIO_COMPRESS_OFF, tx);
if (zap_add(spa->spa_meta_objset,
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_SYNC_BPLIST,
sizeof (uint64_t), 1, &spa->spa_sync_bplist_obj, tx) != 0) {
cmn_err(CE_PANIC, "failed to add bplist");
}
dmu_tx_commit(tx);
spa->spa_sync_on = B_TRUE;
txg_sync_start(spa->spa_dsl_pool);
/*
* We explicitly wait for the first transaction to complete so that our
* bean counters are appropriately updated.
*/
txg_wait_synced(spa->spa_dsl_pool, txg);
spa_config_sync();
mutex_exit(&spa_namespace_lock);
return (0);
}
/*
* Import the given pool into the system. We set up the necessary spa_t and
* then call spa_load() to do the dirty work.
*/
int
spa_import(const char *pool, nvlist_t *config, const char *altroot)
{
spa_t *spa;
int error;
if (!(spa_mode & FWRITE))
return (EROFS);
/*
* If a pool with this name exists, return failure.
*/
mutex_enter(&spa_namespace_lock);
if (spa_lookup(pool) != NULL) {
mutex_exit(&spa_namespace_lock);
return (EEXIST);
}
/*
* Create and initialize the spa structure.
*/
spa = spa_add(pool, altroot);
spa_activate(spa);
/*
* Pass off the heavy lifting to spa_load().
* Pass TRUE for mosconfig because the user-supplied config
* is actually the one to trust when doing an import.
*/
error = spa_load(spa, config, SPA_LOAD_IMPORT, B_TRUE);
if (error) {
spa_unload(spa);
spa_deactivate(spa);
spa_remove(spa);
mutex_exit(&spa_namespace_lock);
return (error);
}
/*
* Update the config cache to include the newly-imported pool.
*/
spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
mutex_exit(&spa_namespace_lock);
/*
* Resilver anything that's out of date.
*/
if (spa_mode & FWRITE)
VERIFY(spa_scrub(spa, POOL_SCRUB_RESILVER, B_TRUE) == 0);
return (0);
}
/*
* This (illegal) pool name is used when temporarily importing a spa_t in order
* to get the vdev stats associated with the imported devices.
*/
#define TRYIMPORT_NAME "$import"
nvlist_t *
spa_tryimport(nvlist_t *tryconfig)
{
nvlist_t *config = NULL;
char *poolname;
spa_t *spa;
uint64_t state;
if (nvlist_lookup_string(tryconfig, ZPOOL_CONFIG_POOL_NAME, &poolname))
return (NULL);
if (nvlist_lookup_uint64(tryconfig, ZPOOL_CONFIG_POOL_STATE, &state))
return (NULL);
/*
* Create and initialize the spa structure.
*/
mutex_enter(&spa_namespace_lock);
spa = spa_add(TRYIMPORT_NAME, NULL);
spa_activate(spa);
/*
* Pass off the heavy lifting to spa_load().
* Pass TRUE for mosconfig because the user-supplied config
* is actually the one to trust when doing an import.
*/
(void) spa_load(spa, tryconfig, SPA_LOAD_TRYIMPORT, B_TRUE);
/*
* If 'tryconfig' was at least parsable, return the current config.
*/
if (spa->spa_root_vdev != NULL) {
spa_config_enter(spa, RW_READER, FTAG);
config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
spa_config_exit(spa, FTAG);
VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
poolname) == 0);
VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
state) == 0);
}
spa_unload(spa);
spa_deactivate(spa);
spa_remove(spa);
mutex_exit(&spa_namespace_lock);
return (config);
}
/*
* Pool export/destroy
*
* The act of destroying or exporting a pool is very simple. We make sure there
* is no more pending I/O and any references to the pool are gone. Then, we
* update the pool state and sync all the labels to disk, removing the
* configuration from the cache afterwards.
*/
static int
spa_export_common(char *pool, int new_state)
{
spa_t *spa;
if (!(spa_mode & FWRITE))
return (EROFS);
mutex_enter(&spa_namespace_lock);
if ((spa = spa_lookup(pool)) == NULL) {
mutex_exit(&spa_namespace_lock);
return (ENOENT);
}
/*
* Put a hold on the pool, drop the namespace lock, stop async tasks,
* reacquire the namespace lock, and see if we can export.
*/
spa_open_ref(spa, FTAG);
mutex_exit(&spa_namespace_lock);
spa_async_suspend(spa);
mutex_enter(&spa_namespace_lock);
spa_close(spa, FTAG);
/*
* The pool will be in core if it's openable,
* in which case we can modify its state.
*/
if (spa->spa_state != POOL_STATE_UNINITIALIZED && spa->spa_sync_on) {
/*
* Objsets may be open only because they're dirty, so we
* have to force it to sync before checking spa_refcnt.
*/
spa_scrub_suspend(spa);
txg_wait_synced(spa->spa_dsl_pool, 0);
/*
* A pool cannot be exported or destroyed if there are active
* references. If we are resetting a pool, allow references by
* fault injection handlers.
*/
if (!spa_refcount_zero(spa) ||
(spa->spa_inject_ref != 0 &&
new_state != POOL_STATE_UNINITIALIZED)) {
spa_scrub_resume(spa);
spa_async_resume(spa);
mutex_exit(&spa_namespace_lock);
return (EBUSY);
}
spa_scrub_resume(spa);
VERIFY(spa_scrub(spa, POOL_SCRUB_NONE, B_TRUE) == 0);
/*
* We want this to be reflected on every label,
* so mark them all dirty. spa_unload() will do the
* final sync that pushes these changes out.
*/
if (new_state != POOL_STATE_UNINITIALIZED) {
spa_config_enter(spa, RW_WRITER, FTAG);
spa->spa_state = new_state;
spa->spa_final_txg = spa_last_synced_txg(spa) + 1;
vdev_config_dirty(spa->spa_root_vdev);
spa_config_exit(spa, FTAG);
}
}
if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
spa_unload(spa);
spa_deactivate(spa);
}
if (new_state != POOL_STATE_UNINITIALIZED) {
spa_remove(spa);
spa_config_sync();
}
mutex_exit(&spa_namespace_lock);
return (0);
}
/*
* Destroy a storage pool.
*/
int
spa_destroy(char *pool)
{
return (spa_export_common(pool, POOL_STATE_DESTROYED));
}
/*
* Export a storage pool.
*/
int
spa_export(char *pool)
{
return (spa_export_common(pool, POOL_STATE_EXPORTED));
}
/*
* Similar to spa_export(), this unloads the spa_t without actually removing it
* from the namespace in any way.
*/
int
spa_reset(char *pool)
{
return (spa_export_common(pool, POOL_STATE_UNINITIALIZED));
}
/*
* ==========================================================================
* Device manipulation
* ==========================================================================
*/
/*
* Add capacity to a storage pool.
*/
int
spa_vdev_add(spa_t *spa, nvlist_t *nvroot)
{
uint64_t txg;
int c, error;
vdev_t *rvd = spa->spa_root_vdev;
vdev_t *vd, *tvd;
txg = spa_vdev_enter(spa);
vd = spa_config_parse(spa, nvroot, NULL, 0, VDEV_ALLOC_ADD);
if (vd == NULL)
return (spa_vdev_exit(spa, vd, txg, EINVAL));
if ((error = vdev_create(vd, txg)) != 0)
return (spa_vdev_exit(spa, vd, txg, error));
/*
* Transfer each new top-level vdev from vd to rvd.
*/
for (c = 0; c < vd->vdev_children; c++) {
tvd = vd->vdev_child[c];
vdev_remove_child(vd, tvd);
tvd->vdev_id = rvd->vdev_children;
vdev_add_child(rvd, tvd);
vdev_config_dirty(tvd);
}
/*
* We have to be careful when adding new vdevs to an existing pool.
* If other threads start allocating from these vdevs before we
* sync the config cache, and we lose power, then upon reboot we may
* fail to open the pool because there are DVAs that the config cache
* can't translate. Therefore, we first add the vdevs without
* initializing metaslabs; sync the config cache (via spa_vdev_exit());
* and then let spa_config_update() initialize the new metaslabs.
*
* spa_load() checks for added-but-not-initialized vdevs, so that
* if we lose power at any point in this sequence, the remaining
* steps will be completed the next time we load the pool.
*/
(void) spa_vdev_exit(spa, vd, txg, 0);
mutex_enter(&spa_namespace_lock);
spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
mutex_exit(&spa_namespace_lock);
return (0);
}
/*
* Attach a device to a mirror. The arguments are the path to any device
* in the mirror, and the nvroot for the new device. If the path specifies
* a device that is not mirrored, we automatically insert the mirror vdev.
*
* If 'replacing' is specified, the new device is intended to replace the
* existing device; in this case the two devices are made into their own
* mirror using the 'replacing' vdev, which is functionally idendical to
* the mirror vdev (it actually reuses all the same ops) but has a few
* extra rules: you can't attach to it after it's been created, and upon
* completion of resilvering, the first disk (the one being replaced)
* is automatically detached.
*/
int
spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot, int replacing)
{
uint64_t txg, open_txg;
int error;
vdev_t *rvd = spa->spa_root_vdev;
vdev_t *oldvd, *newvd, *newrootvd, *pvd, *tvd;
vdev_ops_t *pvops = replacing ? &vdev_replacing_ops : &vdev_mirror_ops;
txg = spa_vdev_enter(spa);
oldvd = vdev_lookup_by_guid(rvd, guid);
if (oldvd == NULL)
return (spa_vdev_exit(spa, NULL, txg, ENODEV));
if (!oldvd->vdev_ops->vdev_op_leaf)
return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
pvd = oldvd->vdev_parent;
/*
* The parent must be a mirror or the root, unless we're replacing;
* in that case, the parent can be anything but another replacing vdev.
*/
if (pvd->vdev_ops != &vdev_mirror_ops &&
pvd->vdev_ops != &vdev_root_ops &&
(!replacing || pvd->vdev_ops == &vdev_replacing_ops))
return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
newrootvd = spa_config_parse(spa, nvroot, NULL, 0, VDEV_ALLOC_ADD);
if (newrootvd == NULL || newrootvd->vdev_children != 1)
return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
newvd = newrootvd->vdev_child[0];
if (!newvd->vdev_ops->vdev_op_leaf)
return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
if ((error = vdev_create(newrootvd, txg)) != 0)
return (spa_vdev_exit(spa, newrootvd, txg, error));
/*
* Compare the new device size with the replaceable/attachable
* device size.
*/
if (newvd->vdev_psize < vdev_get_rsize(oldvd))
return (spa_vdev_exit(spa, newrootvd, txg, EOVERFLOW));
/*
* The new device cannot have a higher alignment requirement
* than the top-level vdev.
*/
if (newvd->vdev_ashift > oldvd->vdev_top->vdev_ashift)
return (spa_vdev_exit(spa, newrootvd, txg, EDOM));
/*
* If this is an in-place replacement, update oldvd's path and devid
* to make it distinguishable from newvd, and unopenable from now on.
*/
if (strcmp(oldvd->vdev_path, newvd->vdev_path) == 0) {
spa_strfree(oldvd->vdev_path);
oldvd->vdev_path = kmem_alloc(strlen(newvd->vdev_path) + 5,
KM_SLEEP);
(void) sprintf(oldvd->vdev_path, "%s/%s",
newvd->vdev_path, "old");
if (oldvd->vdev_devid != NULL) {
spa_strfree(oldvd->vdev_devid);
oldvd->vdev_devid = NULL;
}
}
/*
* If the parent is not a mirror, or if we're replacing,
* insert the new mirror/replacing vdev above oldvd.
*/
if (pvd->vdev_ops != pvops)
pvd = vdev_add_parent(oldvd, pvops);
ASSERT(pvd->vdev_top->vdev_parent == rvd);
ASSERT(pvd->vdev_ops == pvops);
ASSERT(oldvd->vdev_parent == pvd);
/*
* Extract the new device from its root and add it to pvd.
*/
vdev_remove_child(newrootvd, newvd);
newvd->vdev_id = pvd->vdev_children;
vdev_add_child(pvd, newvd);
/*
* If newvd is smaller than oldvd, but larger than its rsize,
* the addition of newvd may have decreased our parent's asize.
*/
pvd->vdev_asize = MIN(pvd->vdev_asize, newvd->vdev_asize);
tvd = newvd->vdev_top;
ASSERT(pvd->vdev_top == tvd);
ASSERT(tvd->vdev_parent == rvd);
vdev_config_dirty(tvd);
/*
* Set newvd's DTL to [TXG_INITIAL, open_txg]. It will propagate
* upward when spa_vdev_exit() calls vdev_dtl_reassess().
*/
open_txg = txg + TXG_CONCURRENT_STATES - 1;
mutex_enter(&newvd->vdev_dtl_lock);
space_map_add(&newvd->vdev_dtl_map, TXG_INITIAL,
open_txg - TXG_INITIAL + 1);
mutex_exit(&newvd->vdev_dtl_lock);
dprintf("attached %s in txg %llu\n", newvd->vdev_path, txg);
/*
* Mark newvd's DTL dirty in this txg.
*/
vdev_dirty(tvd, VDD_DTL, newvd, txg);
(void) spa_vdev_exit(spa, newrootvd, open_txg, 0);
/*
* Kick off a resilver to update newvd.
*/
VERIFY(spa_scrub(spa, POOL_SCRUB_RESILVER, B_TRUE) == 0);
return (0);
}
/*
* Detach a device from a mirror or replacing vdev.
* If 'replace_done' is specified, only detach if the parent
* is a replacing vdev.
*/
int
spa_vdev_detach(spa_t *spa, uint64_t guid, int replace_done)
{
uint64_t txg;
int c, t, error;
vdev_t *rvd = spa->spa_root_vdev;
vdev_t *vd, *pvd, *cvd, *tvd;
txg = spa_vdev_enter(spa);
vd = vdev_lookup_by_guid(rvd, guid);
if (vd == NULL)
return (spa_vdev_exit(spa, NULL, txg, ENODEV));
if (!vd->vdev_ops->vdev_op_leaf)
return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
pvd = vd->vdev_parent;
/*
* If replace_done is specified, only remove this device if it's
* the first child of a replacing vdev.
*/
if (replace_done &&
(vd->vdev_id != 0 || pvd->vdev_ops != &vdev_replacing_ops))
return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
/*
* Only mirror and replacing vdevs support detach.
*/
if (pvd->vdev_ops != &vdev_replacing_ops &&
pvd->vdev_ops != &vdev_mirror_ops)
return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
/*
* If there's only one replica, you can't detach it.
*/
if (pvd->vdev_children <= 1)
return (spa_vdev_exit(spa, NULL, txg, EBUSY));
/*
* If all siblings have non-empty DTLs, this device may have the only
* valid copy of the data, which means we cannot safely detach it.
*
* XXX -- as in the vdev_offline() case, we really want a more
* precise DTL check.
*/
for (c = 0; c < pvd->vdev_children; c++) {
uint64_t dirty;
cvd = pvd->vdev_child[c];
if (cvd == vd)
continue;
if (vdev_is_dead(cvd))
continue;
mutex_enter(&cvd->vdev_dtl_lock);
dirty = cvd->vdev_dtl_map.sm_space |
cvd->vdev_dtl_scrub.sm_space;
mutex_exit(&cvd->vdev_dtl_lock);
if (!dirty)
break;
}
if (c == pvd->vdev_children)
return (spa_vdev_exit(spa, NULL, txg, EBUSY));
/*
* Erase the disk labels so the disk can be used for other things.
* This must be done after all other error cases are handled,
* but before we disembowel vd (so we can still do I/O to it).
* But if we can't do it, don't treat the error as fatal --
* it may be that the unwritability of the disk is the reason
* it's being detached!
*/
error = vdev_label_init(vd, 0);
if (error)
dprintf("unable to erase labels on %s\n", vdev_description(vd));
/*
* Remove vd from its parent and compact the parent's children.
*/
vdev_remove_child(pvd, vd);
vdev_compact_children(pvd);
/*
* Remember one of the remaining children so we can get tvd below.
*/
cvd = pvd->vdev_child[0];
/*
* If the parent mirror/replacing vdev only has one child,
* the parent is no longer needed. Remove it from the tree.
*/
if (pvd->vdev_children == 1)
vdev_remove_parent(cvd);
/*
* We don't set tvd until now because the parent we just removed
* may have been the previous top-level vdev.
*/
tvd = cvd->vdev_top;
ASSERT(tvd->vdev_parent == rvd);
/*
* Reopen this top-level vdev to reassess health after detach.
*/
vdev_reopen(tvd);
/*
* If the device we just detached was smaller than the others,
* it may be possible to add metaslabs (i.e. grow the pool).
* vdev_metaslab_init() can't fail because the existing metaslabs
* are already in core, so there's nothing to read from disk.
*/
VERIFY(vdev_metaslab_init(tvd, txg) == 0);
vdev_config_dirty(tvd);
/*
* Mark vd's DTL as dirty in this txg.
* vdev_dtl_sync() will see that vd->vdev_detached is set
* and free vd's DTL object in syncing context.
* But first make sure we're not on any *other* txg's DTL list,
* to prevent vd from being accessed after it's freed.
*/
for (t = 0; t < TXG_SIZE; t++)
(void) txg_list_remove_this(&tvd->vdev_dtl_list, vd, t);
vd->vdev_detached = B_TRUE;
vdev_dirty(tvd, VDD_DTL, vd, txg);
dprintf("detached %s in txg %llu\n", vd->vdev_path, txg);
return (spa_vdev_exit(spa, vd, txg, 0));
}
/*
* Find any device that's done replacing, so we can detach it.
*/
static vdev_t *
spa_vdev_replace_done_hunt(vdev_t *vd)
{
vdev_t *newvd, *oldvd;
int c;
for (c = 0; c < vd->vdev_children; c++) {
oldvd = spa_vdev_replace_done_hunt(vd->vdev_child[c]);
if (oldvd != NULL)
return (oldvd);
}
if (vd->vdev_ops == &vdev_replacing_ops && vd->vdev_children == 2) {
oldvd = vd->vdev_child[0];
newvd = vd->vdev_child[1];
mutex_enter(&newvd->vdev_dtl_lock);
if (newvd->vdev_dtl_map.sm_space == 0 &&
newvd->vdev_dtl_scrub.sm_space == 0) {
mutex_exit(&newvd->vdev_dtl_lock);
return (oldvd);
}
mutex_exit(&newvd->vdev_dtl_lock);
}
return (NULL);
}
static void
spa_vdev_replace_done(spa_t *spa)
{
vdev_t *vd;
uint64_t guid;
spa_config_enter(spa, RW_READER, FTAG);
while ((vd = spa_vdev_replace_done_hunt(spa->spa_root_vdev)) != NULL) {
guid = vd->vdev_guid;
spa_config_exit(spa, FTAG);
if (spa_vdev_detach(spa, guid, B_TRUE) != 0)
return;
spa_config_enter(spa, RW_READER, FTAG);
}
spa_config_exit(spa, FTAG);
}
/*
* Update the stored path for this vdev. Dirty the vdev configuration, relying
* on spa_vdev_enter/exit() to synchronize the labels and cache.
*/
int
spa_vdev_setpath(spa_t *spa, uint64_t guid, const char *newpath)
{
vdev_t *rvd, *vd;
uint64_t txg;
rvd = spa->spa_root_vdev;
txg = spa_vdev_enter(spa);
if ((vd = vdev_lookup_by_guid(rvd, guid)) == NULL)
return (spa_vdev_exit(spa, NULL, txg, ENOENT));
if (!vd->vdev_ops->vdev_op_leaf)
return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
spa_strfree(vd->vdev_path);
vd->vdev_path = spa_strdup(newpath);
vdev_config_dirty(vd->vdev_top);
return (spa_vdev_exit(spa, NULL, txg, 0));
}
/*
* ==========================================================================
* SPA Scrubbing
* ==========================================================================
*/
void
spa_scrub_throttle(spa_t *spa, int direction)
{
mutex_enter(&spa->spa_scrub_lock);
spa->spa_scrub_throttled += direction;
ASSERT(spa->spa_scrub_throttled >= 0);
if (spa->spa_scrub_throttled == 0)
cv_broadcast(&spa->spa_scrub_io_cv);
mutex_exit(&spa->spa_scrub_lock);
}
static void
spa_scrub_io_done(zio_t *zio)
{
spa_t *spa = zio->io_spa;
zio_buf_free(zio->io_data, zio->io_size);
mutex_enter(&spa->spa_scrub_lock);
if (zio->io_error && !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
vdev_t *vd = zio->io_vd;
spa->spa_scrub_errors++;
mutex_enter(&vd->vdev_stat_lock);
vd->vdev_stat.vs_scrub_errors++;
mutex_exit(&vd->vdev_stat_lock);
}
if (--spa->spa_scrub_inflight == 0) {
cv_broadcast(&spa->spa_scrub_io_cv);
ASSERT(spa->spa_scrub_throttled == 0);
}
mutex_exit(&spa->spa_scrub_lock);
}
static void
spa_scrub_io_start(spa_t *spa, blkptr_t *bp, int priority, int flags,
zbookmark_t *zb)
{
size_t size = BP_GET_LSIZE(bp);
void *data = zio_buf_alloc(size);
mutex_enter(&spa->spa_scrub_lock);
spa->spa_scrub_inflight++;
mutex_exit(&spa->spa_scrub_lock);
if (zb->zb_level == -1 && BP_GET_TYPE(bp) != DMU_OT_OBJSET)
flags |= ZIO_FLAG_SPECULATIVE; /* intent log block */
flags |= ZIO_FLAG_CANFAIL;
zio_nowait(zio_read(NULL, spa, bp, data, size,
spa_scrub_io_done, NULL, priority, flags, zb));
}
/* ARGSUSED */
static int
spa_scrub_cb(traverse_blk_cache_t *bc, spa_t *spa, void *a)
{
blkptr_t *bp = &bc->bc_blkptr;
vdev_t *vd = vdev_lookup_top(spa, DVA_GET_VDEV(&bp->blk_dva[0]));
if (bc->bc_errno || vd == NULL) {
/*
* We can't scrub this block, but we can continue to scrub
* the rest of the pool. Note the error and move along.
*/
mutex_enter(&spa->spa_scrub_lock);
spa->spa_scrub_errors++;
mutex_exit(&spa->spa_scrub_lock);
if (vd != NULL) {
mutex_enter(&vd->vdev_stat_lock);
vd->vdev_stat.vs_scrub_errors++;
mutex_exit(&vd->vdev_stat_lock);
}
return (ERESTART);
}
ASSERT(bp->blk_birth < spa->spa_scrub_maxtxg);
/*
* Keep track of how much data we've examined so that
* zpool(1M) status can make useful progress reports.
*/
mutex_enter(&vd->vdev_stat_lock);
vd->vdev_stat.vs_scrub_examined += BP_GET_ASIZE(bp);
mutex_exit(&vd->vdev_stat_lock);
if (spa->spa_scrub_type == POOL_SCRUB_RESILVER) {
if (DVA_GET_GANG(&bp->blk_dva[0])) {
/*
* Gang members may be spread across multiple vdevs,
* so the best we can do is look at the pool-wide DTL.
* XXX -- it would be better to change our allocation
* policy to ensure that this can't happen.
*/
vd = spa->spa_root_vdev;
}
if (vdev_dtl_contains(&vd->vdev_dtl_map, bp->blk_birth, 1)) {
spa_scrub_io_start(spa, bp, ZIO_PRIORITY_RESILVER,
ZIO_FLAG_RESILVER, &bc->bc_bookmark);
}
} else {
spa_scrub_io_start(spa, bp, ZIO_PRIORITY_SCRUB,
ZIO_FLAG_SCRUB, &bc->bc_bookmark);
}
return (0);
}
static void
spa_scrub_thread(spa_t *spa)
{
callb_cpr_t cprinfo;
traverse_handle_t *th = spa->spa_scrub_th;
vdev_t *rvd = spa->spa_root_vdev;
pool_scrub_type_t scrub_type = spa->spa_scrub_type;
int error = 0;
boolean_t complete;
CALLB_CPR_INIT(&cprinfo, &spa->spa_scrub_lock, callb_generic_cpr, FTAG);
/*
* If we're restarting due to a snapshot create/delete,
* wait for that to complete.
*/
txg_wait_synced(spa_get_dsl(spa), 0);
dprintf("start %s mintxg=%llu maxtxg=%llu\n",
scrub_type == POOL_SCRUB_RESILVER ? "resilver" : "scrub",
spa->spa_scrub_mintxg, spa->spa_scrub_maxtxg);
spa_config_enter(spa, RW_WRITER, FTAG);
vdev_reopen(rvd); /* purge all vdev caches */
vdev_config_dirty(rvd); /* rewrite all disk labels */
vdev_scrub_stat_update(rvd, scrub_type, B_FALSE);
spa_config_exit(spa, FTAG);
mutex_enter(&spa->spa_scrub_lock);
spa->spa_scrub_errors = 0;
spa->spa_scrub_active = 1;
ASSERT(spa->spa_scrub_inflight == 0);
ASSERT(spa->spa_scrub_throttled == 0);
while (!spa->spa_scrub_stop) {
CALLB_CPR_SAFE_BEGIN(&cprinfo);
while (spa->spa_scrub_suspended) {
spa->spa_scrub_active = 0;
cv_broadcast(&spa->spa_scrub_cv);
cv_wait(&spa->spa_scrub_cv, &spa->spa_scrub_lock);
spa->spa_scrub_active = 1;
}
CALLB_CPR_SAFE_END(&cprinfo, &spa->spa_scrub_lock);
if (spa->spa_scrub_restart_txg != 0)
break;
mutex_exit(&spa->spa_scrub_lock);
error = traverse_more(th);
mutex_enter(&spa->spa_scrub_lock);
if (error != EAGAIN)
break;
while (spa->spa_scrub_throttled > 0)
cv_wait(&spa->spa_scrub_io_cv, &spa->spa_scrub_lock);
}
while (spa->spa_scrub_inflight)
cv_wait(&spa->spa_scrub_io_cv, &spa->spa_scrub_lock);
spa->spa_scrub_active = 0;
cv_broadcast(&spa->spa_scrub_cv);
mutex_exit(&spa->spa_scrub_lock);
spa_config_enter(spa, RW_WRITER, FTAG);
mutex_enter(&spa->spa_scrub_lock);
/*
* Note: we check spa_scrub_restart_txg under both spa_scrub_lock
* AND the spa config lock to synchronize with any config changes
* that revise the DTLs under spa_vdev_enter() / spa_vdev_exit().
*/
if (spa->spa_scrub_restart_txg != 0)
error = ERESTART;
if (spa->spa_scrub_stop)
error = EINTR;
/*
* Even if there were uncorrectable errors, we consider the scrub
* completed. The downside is that if there is a transient error during
* a resilver, we won't resilver the data properly to the target. But
* if the damage is permanent (more likely) we will resilver forever,
* which isn't really acceptable. Since there is enough information for
* the user to know what has failed and why, this seems like a more
* tractable approach.
*/
complete = (error == 0);
dprintf("end %s to maxtxg=%llu %s, traverse=%d, %llu errors, stop=%u\n",
scrub_type == POOL_SCRUB_RESILVER ? "resilver" : "scrub",
spa->spa_scrub_maxtxg, complete ? "done" : "FAILED",
error, spa->spa_scrub_errors, spa->spa_scrub_stop);
mutex_exit(&spa->spa_scrub_lock);
/*
* If the scrub/resilver completed, update all DTLs to reflect this.
* Whether it succeeded or not, vacate all temporary scrub DTLs.
*/
vdev_dtl_reassess(rvd, spa_last_synced_txg(spa) + 1,
complete ? spa->spa_scrub_maxtxg : 0, B_TRUE);
vdev_scrub_stat_update(rvd, POOL_SCRUB_NONE, complete);
spa_errlog_rotate(spa);
spa_config_exit(spa, FTAG);
mutex_enter(&spa->spa_scrub_lock);
/*
* We may have finished replacing a device.
* Let the async thread assess this and handle the detach.
*/
spa_async_request(spa, SPA_ASYNC_REPLACE_DONE);
/*
* If we were told to restart, our final act is to start a new scrub.
*/
if (error == ERESTART)
spa_async_request(spa, scrub_type == POOL_SCRUB_RESILVER ?
SPA_ASYNC_RESILVER : SPA_ASYNC_SCRUB);
spa->spa_scrub_type = POOL_SCRUB_NONE;
spa->spa_scrub_active = 0;
spa->spa_scrub_thread = NULL;
cv_broadcast(&spa->spa_scrub_cv);
CALLB_CPR_EXIT(&cprinfo); /* drops &spa->spa_scrub_lock */
thread_exit();
}
void
spa_scrub_suspend(spa_t *spa)
{
mutex_enter(&spa->spa_scrub_lock);
spa->spa_scrub_suspended++;
while (spa->spa_scrub_active) {
cv_broadcast(&spa->spa_scrub_cv);
cv_wait(&spa->spa_scrub_cv, &spa->spa_scrub_lock);
}
while (spa->spa_scrub_inflight)
cv_wait(&spa->spa_scrub_io_cv, &spa->spa_scrub_lock);
mutex_exit(&spa->spa_scrub_lock);
}
void
spa_scrub_resume(spa_t *spa)
{
mutex_enter(&spa->spa_scrub_lock);
ASSERT(spa->spa_scrub_suspended != 0);
if (--spa->spa_scrub_suspended == 0)
cv_broadcast(&spa->spa_scrub_cv);
mutex_exit(&spa->spa_scrub_lock);
}
void
spa_scrub_restart(spa_t *spa, uint64_t txg)
{
/*
* Something happened (e.g. snapshot create/delete) that means
* we must restart any in-progress scrubs. The itinerary will
* fix this properly.
*/
mutex_enter(&spa->spa_scrub_lock);
spa->spa_scrub_restart_txg = txg;
mutex_exit(&spa->spa_scrub_lock);
}
int
spa_scrub(spa_t *spa, pool_scrub_type_t type, boolean_t force)
{
space_seg_t *ss;
uint64_t mintxg, maxtxg;
vdev_t *rvd = spa->spa_root_vdev;
if ((uint_t)type >= POOL_SCRUB_TYPES)
return (ENOTSUP);
mutex_enter(&spa->spa_scrub_lock);
/*
* If there's a scrub or resilver already in progress, stop it.
*/
while (spa->spa_scrub_thread != NULL) {
/*
* Don't stop a resilver unless forced.
*/
if (spa->spa_scrub_type == POOL_SCRUB_RESILVER && !force) {
mutex_exit(&spa->spa_scrub_lock);
return (EBUSY);
}
spa->spa_scrub_stop = 1;
cv_broadcast(&spa->spa_scrub_cv);
cv_wait(&spa->spa_scrub_cv, &spa->spa_scrub_lock);
}
/*
* Terminate the previous traverse.
*/
if (spa->spa_scrub_th != NULL) {
traverse_fini(spa->spa_scrub_th);
spa->spa_scrub_th = NULL;
}
if (rvd == NULL) {
ASSERT(spa->spa_scrub_stop == 0);
ASSERT(spa->spa_scrub_type == type);
ASSERT(spa->spa_scrub_restart_txg == 0);
mutex_exit(&spa->spa_scrub_lock);
return (0);
}
mintxg = TXG_INITIAL - 1;
maxtxg = spa_last_synced_txg(spa) + 1;
mutex_enter(&rvd->vdev_dtl_lock);
if (rvd->vdev_dtl_map.sm_space == 0) {
/*
* The pool-wide DTL is empty.
* If this is a resilver, there's nothing to do except
* check whether any in-progress replacements have completed.
*/
if (type == POOL_SCRUB_RESILVER) {
type = POOL_SCRUB_NONE;
spa_async_request(spa, SPA_ASYNC_REPLACE_DONE);
}
} else {
/*
* The pool-wide DTL is non-empty.
* If this is a normal scrub, upgrade to a resilver instead.
*/
if (type == POOL_SCRUB_EVERYTHING)
type = POOL_SCRUB_RESILVER;
}
if (type == POOL_SCRUB_RESILVER) {
/*
* Determine the resilvering boundaries.
*
* Note: (mintxg, maxtxg) is an open interval,
* i.e. mintxg and maxtxg themselves are not included.
*
* Note: for maxtxg, we MIN with spa_last_synced_txg(spa) + 1
* so we don't claim to resilver a txg that's still changing.
*/
ss = avl_first(&rvd->vdev_dtl_map.sm_root);
mintxg = ss->ss_start - 1;
ss = avl_last(&rvd->vdev_dtl_map.sm_root);
maxtxg = MIN(ss->ss_end, maxtxg);
}
mutex_exit(&rvd->vdev_dtl_lock);
spa->spa_scrub_stop = 0;
spa->spa_scrub_type = type;
spa->spa_scrub_restart_txg = 0;
if (type != POOL_SCRUB_NONE) {
spa->spa_scrub_mintxg = mintxg;
spa->spa_scrub_maxtxg = maxtxg;
spa->spa_scrub_th = traverse_init(spa, spa_scrub_cb, NULL,
ADVANCE_PRE | ADVANCE_PRUNE | ADVANCE_ZIL,
ZIO_FLAG_CANFAIL);
traverse_add_pool(spa->spa_scrub_th, mintxg, maxtxg);
spa->spa_scrub_thread = thread_create(NULL, 0,
spa_scrub_thread, spa, 0, &p0, TS_RUN, minclsyspri);
}
mutex_exit(&spa->spa_scrub_lock);
return (0);
}
/*
* ==========================================================================
* SPA async task processing
* ==========================================================================
*/
static void
spa_async_reopen(spa_t *spa)
{
vdev_t *rvd = spa->spa_root_vdev;
vdev_t *tvd;
int c;
spa_config_enter(spa, RW_WRITER, FTAG);
for (c = 0; c < rvd->vdev_children; c++) {
tvd = rvd->vdev_child[c];
if (tvd->vdev_reopen_wanted) {
tvd->vdev_reopen_wanted = 0;
vdev_reopen(tvd);
}
}
spa_config_exit(spa, FTAG);
}
static void
spa_async_thread(spa_t *spa)
{
int tasks;
ASSERT(spa->spa_sync_on);
mutex_enter(&spa->spa_async_lock);
tasks = spa->spa_async_tasks;
spa->spa_async_tasks = 0;
mutex_exit(&spa->spa_async_lock);
/*
* See if the config needs to be updated.
*/
if (tasks & SPA_ASYNC_CONFIG_UPDATE) {
mutex_enter(&spa_namespace_lock);
spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
mutex_exit(&spa_namespace_lock);
}
/*
* See if any devices need to be reopened.
*/
if (tasks & SPA_ASYNC_REOPEN)
spa_async_reopen(spa);
/*
* If any devices are done replacing, detach them.
*/
if (tasks & SPA_ASYNC_REPLACE_DONE)
spa_vdev_replace_done(spa);
/*
* Kick off a scrub.
*/
if (tasks & SPA_ASYNC_SCRUB)
VERIFY(spa_scrub(spa, POOL_SCRUB_EVERYTHING, B_TRUE) == 0);
/*
* Kick off a resilver.
*/
if (tasks & SPA_ASYNC_RESILVER)
VERIFY(spa_scrub(spa, POOL_SCRUB_RESILVER, B_TRUE) == 0);
/*
* Let the world know that we're done.
*/
mutex_enter(&spa->spa_async_lock);
spa->spa_async_thread = NULL;
cv_broadcast(&spa->spa_async_cv);
mutex_exit(&spa->spa_async_lock);
thread_exit();
}
void
spa_async_suspend(spa_t *spa)
{
mutex_enter(&spa->spa_async_lock);
spa->spa_async_suspended++;
while (spa->spa_async_thread != NULL)
cv_wait(&spa->spa_async_cv, &spa->spa_async_lock);
mutex_exit(&spa->spa_async_lock);
}
void
spa_async_resume(spa_t *spa)
{
mutex_enter(&spa->spa_async_lock);
ASSERT(spa->spa_async_suspended != 0);
spa->spa_async_suspended--;
mutex_exit(&spa->spa_async_lock);
}
static void
spa_async_dispatch(spa_t *spa)
{
mutex_enter(&spa->spa_async_lock);
if (spa->spa_async_tasks && !spa->spa_async_suspended &&
spa->spa_async_thread == NULL &&
rootdir != NULL && !vn_is_readonly(rootdir))
spa->spa_async_thread = thread_create(NULL, 0,
spa_async_thread, spa, 0, &p0, TS_RUN, maxclsyspri);
mutex_exit(&spa->spa_async_lock);
}
void
spa_async_request(spa_t *spa, int task)
{
mutex_enter(&spa->spa_async_lock);
spa->spa_async_tasks |= task;
mutex_exit(&spa->spa_async_lock);
}
/*
* ==========================================================================
* SPA syncing routines
* ==========================================================================
*/
static void
spa_sync_deferred_frees(spa_t *spa, uint64_t txg)
{
bplist_t *bpl = &spa->spa_sync_bplist;
dmu_tx_t *tx;
blkptr_t blk;
uint64_t itor = 0;
zio_t *zio;
int error;
uint8_t c = 1;
zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CONFIG_HELD);
while (bplist_iterate(bpl, &itor, &blk) == 0)
zio_nowait(zio_free(zio, spa, txg, &blk, NULL, NULL));
error = zio_wait(zio);
ASSERT3U(error, ==, 0);
tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
bplist_vacate(bpl, tx);
/*
* Pre-dirty the first block so we sync to convergence faster.
* (Usually only the first block is needed.)
*/
dmu_write(spa->spa_meta_objset, spa->spa_sync_bplist_obj, 0, 1, &c, tx);
dmu_tx_commit(tx);
}
static void
spa_sync_config_object(spa_t *spa, dmu_tx_t *tx)
{
nvlist_t *config;
char *packed = NULL;
size_t nvsize = 0;
dmu_buf_t *db;
if (list_is_empty(&spa->spa_dirty_list))
return;
config = spa_config_generate(spa, NULL, dmu_tx_get_txg(tx), B_FALSE);
if (spa->spa_config_syncing)
nvlist_free(spa->spa_config_syncing);
spa->spa_config_syncing = config;
VERIFY(nvlist_size(config, &nvsize, NV_ENCODE_XDR) == 0);
packed = kmem_alloc(nvsize, KM_SLEEP);
VERIFY(nvlist_pack(config, &packed, &nvsize, NV_ENCODE_XDR,
KM_SLEEP) == 0);
dmu_write(spa->spa_meta_objset, spa->spa_config_object, 0, nvsize,
packed, tx);
kmem_free(packed, nvsize);
VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset,
spa->spa_config_object, FTAG, &db));
dmu_buf_will_dirty(db, tx);
*(uint64_t *)db->db_data = nvsize;
dmu_buf_rele(db, FTAG);
}
/*
* Sync the specified transaction group. New blocks may be dirtied as
* part of the process, so we iterate until it converges.
*/
void
spa_sync(spa_t *spa, uint64_t txg)
{
dsl_pool_t *dp = spa->spa_dsl_pool;
objset_t *mos = spa->spa_meta_objset;
bplist_t *bpl = &spa->spa_sync_bplist;
vdev_t *rvd = spa->spa_root_vdev;
vdev_t *vd;
dmu_tx_t *tx;
int dirty_vdevs;
/*
* Lock out configuration changes.
*/
spa_config_enter(spa, RW_READER, FTAG);
spa->spa_syncing_txg = txg;
spa->spa_sync_pass = 0;
VERIFY(0 == bplist_open(bpl, mos, spa->spa_sync_bplist_obj));
/*
* If anything has changed in this txg, push the deferred frees
* from the previous txg. If not, leave them alone so that we
* don't generate work on an otherwise idle system.
*/
if (!txg_list_empty(&dp->dp_dirty_datasets, txg) ||
!txg_list_empty(&dp->dp_dirty_dirs, txg))
spa_sync_deferred_frees(spa, txg);
/*
* Iterate to convergence.
*/
do {
spa->spa_sync_pass++;
tx = dmu_tx_create_assigned(dp, txg);
spa_sync_config_object(spa, tx);
dmu_tx_commit(tx);
spa_errlog_sync(spa, txg);
dsl_pool_sync(dp, txg);
dirty_vdevs = 0;
while (vd = txg_list_remove(&spa->spa_vdev_txg_list, txg)) {
vdev_sync(vd, txg);
dirty_vdevs++;
}
tx = dmu_tx_create_assigned(dp, txg);
bplist_sync(bpl, tx);
dmu_tx_commit(tx);
} while (dirty_vdevs);
bplist_close(bpl);
dprintf("txg %llu passes %d\n", txg, spa->spa_sync_pass);
/*
* Rewrite the vdev configuration (which includes the uberblock)
* to commit the transaction group.
*
* If there are any dirty vdevs, sync the uberblock to all vdevs.
* Otherwise, pick a random top-level vdev that's known to be
* visible in the config cache (see spa_vdev_add() for details).
* If the write fails, try the next vdev until we're tried them all.
*/
if (!list_is_empty(&spa->spa_dirty_list)) {
VERIFY(vdev_config_sync(rvd, txg) == 0);
} else {
int children = rvd->vdev_children;
int c0 = spa_get_random(children);
int c;
for (c = 0; c < children; c++) {
vd = rvd->vdev_child[(c0 + c) % children];
if (vd->vdev_ms_array == 0)
continue;
if (vdev_config_sync(vd, txg) == 0)
break;
}
if (c == children)
VERIFY(vdev_config_sync(rvd, txg) == 0);
}
/*
* Clear the dirty config list.
*/
while ((vd = list_head(&spa->spa_dirty_list)) != NULL)
vdev_config_clean(vd);
/*
* Now that the new config has synced transactionally,
* let it become visible to the config cache.
*/
if (spa->spa_config_syncing != NULL) {
spa_config_set(spa, spa->spa_config_syncing);
spa->spa_config_txg = txg;
spa->spa_config_syncing = NULL;
}
/*
* Make a stable copy of the fully synced uberblock.
* We use this as the root for pool traversals.
*/
spa->spa_traverse_wanted = 1; /* tells traverse_more() to stop */
spa_scrub_suspend(spa); /* stop scrubbing and finish I/Os */
rw_enter(&spa->spa_traverse_lock, RW_WRITER);
spa->spa_traverse_wanted = 0;
spa->spa_ubsync = spa->spa_uberblock;
rw_exit(&spa->spa_traverse_lock);
spa_scrub_resume(spa); /* resume scrub with new ubsync */
/*
* Clean up the ZIL records for the synced txg.
*/
dsl_pool_zil_clean(dp);
/*
* Update usable space statistics.
*/
while (vd = txg_list_remove(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)))
vdev_sync_done(vd, txg);
/*
* It had better be the case that we didn't dirty anything
* since spa_sync_labels().
*/
ASSERT(txg_list_empty(&dp->dp_dirty_datasets, txg));
ASSERT(txg_list_empty(&dp->dp_dirty_dirs, txg));
ASSERT(txg_list_empty(&spa->spa_vdev_txg_list, txg));
ASSERT(bpl->bpl_queue == NULL);
spa_config_exit(spa, FTAG);
/*
* If any async tasks have been requested, kick them off.
*/
spa_async_dispatch(spa);
}
/*
* Sync all pools. We don't want to hold the namespace lock across these
* operations, so we take a reference on the spa_t and drop the lock during the
* sync.
*/
void
spa_sync_allpools(void)
{
spa_t *spa = NULL;
mutex_enter(&spa_namespace_lock);
while ((spa = spa_next(spa)) != NULL) {
if (spa_state(spa) != POOL_STATE_ACTIVE)
continue;
spa_open_ref(spa, FTAG);
mutex_exit(&spa_namespace_lock);
txg_wait_synced(spa_get_dsl(spa), 0);
mutex_enter(&spa_namespace_lock);
spa_close(spa, FTAG);
}
mutex_exit(&spa_namespace_lock);
}
/*
* ==========================================================================
* Miscellaneous routines
* ==========================================================================
*/
/*
* Remove all pools in the system.
*/
void
spa_evict_all(void)
{
spa_t *spa;
/*
* Remove all cached state. All pools should be closed now,
* so every spa in the AVL tree should be unreferenced.
*/
mutex_enter(&spa_namespace_lock);
while ((spa = spa_next(NULL)) != NULL) {
/*
* Stop async tasks. The async thread may need to detach
* a device that's been replaced, which requires grabbing
* spa_namespace_lock, so we must drop it here.
*/
spa_open_ref(spa, FTAG);
mutex_exit(&spa_namespace_lock);
spa_async_suspend(spa);
VERIFY(spa_scrub(spa, POOL_SCRUB_NONE, B_TRUE) == 0);
mutex_enter(&spa_namespace_lock);
spa_close(spa, FTAG);
if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
spa_unload(spa);
spa_deactivate(spa);
}
spa_remove(spa);
}
mutex_exit(&spa_namespace_lock);
}
vdev_t *
spa_lookup_by_guid(spa_t *spa, uint64_t guid)
{
return (vdev_lookup_by_guid(spa->spa_root_vdev, guid));
}