2 stable fixes for dm-cache and 1 3.19 DM core fix:
- Fix potential for dm-cache metadata corruption via stale metadata
buffers being used when switching an inactive cache table to active;
this could occur due to each table having it's own bufio client rather
than sharing the client between tables.
- Fix dm-cache target to properly account for discard IO while
suspending otherwise IO quiescing could complete prematurely.
- Fix DM core's handling of multiple internal suspends by maintaining an
'internal_suspend_count' and only resuming the device when this count
drops to zero.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEbBAABAgAGBQJUxEXBAAoJEMUj8QotnQNaejYH+LQY5iTHaBQxvDq78pJIItAc
s8Uh+L0NdHXiDbS+2sSnAfYVfbL+YQ7ivUaXv8I9zfW+mVDREYk91VTSYP8SaM7r
n5ja/PMWe3DhbZo39rZCJzRZpt1TTzIGRPFXzflKbco5HVTHqXUEurGnF4Z5ivXB
w1I89WqHPY1Y9W7AiahJk12474IhHMa9urb9l5y/SUMSA3kNos1yubRfAlxBaWN/
2eiD5bZB50Qvy+DGJz00yBvP/uauyIxjI0C9LM8ELCBOyoENWPP8H8IqRY6fg6hW
K5ke8nN3/G8W6UiAI7KCdUFP8tM+RrOjPSxL0JtZFj1xuE4oUnB6VqO9769v+A==
=wHbY
-----END PGP SIGNATURE-----
Merge tag 'dm-3.19-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
"Two stable fixes for dm-cache and one 3.19 DM core fix:
- fix potential for dm-cache metadata corruption via stale metadata
buffers being used when switching an inactive cache table to
active; this could occur due to each table having it's own bufio
client rather than sharing the client between tables.
- fix dm-cache target to properly account for discard IO while
suspending otherwise IO quiescing could complete prematurely.
- fix DM core's handling of multiple internal suspends by maintaining
an 'internal_suspend_count' and only resuming the device when this
count drops to zero"
* tag 'dm-3.19-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: fix handling of multiple internal suspends
dm cache: fix problematic dual use of a single migration count variable
dm cache: share cache-metadata object across inactive and active DM tables
This commit is contained in:
Linus Torvalds
Коммит
bfc835b571
|
|
@ -94,6 +94,9 @@ struct cache_disk_superblock {
|
|||
} __packed;
|
||||
|
||||
struct dm_cache_metadata {
|
||||
atomic_t ref_count;
|
||||
struct list_head list;
|
||||
|
||||
struct block_device *bdev;
|
||||
struct dm_block_manager *bm;
|
||||
struct dm_space_map *metadata_sm;
|
||||
|
|
@ -669,10 +672,10 @@ static void unpack_value(__le64 value_le, dm_oblock_t *block, unsigned *flags)
|
|||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
|
||||
sector_t data_block_size,
|
||||
bool may_format_device,
|
||||
size_t policy_hint_size)
|
||||
static struct dm_cache_metadata *metadata_open(struct block_device *bdev,
|
||||
sector_t data_block_size,
|
||||
bool may_format_device,
|
||||
size_t policy_hint_size)
|
||||
{
|
||||
int r;
|
||||
struct dm_cache_metadata *cmd;
|
||||
|
|
@ -683,6 +686,7 @@ struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
|
|||
return NULL;
|
||||
}
|
||||
|
||||
atomic_set(&cmd->ref_count, 1);
|
||||
init_rwsem(&cmd->root_lock);
|
||||
cmd->bdev = bdev;
|
||||
cmd->data_block_size = data_block_size;
|
||||
|
|
@ -705,10 +709,95 @@ struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
|
|||
return cmd;
|
||||
}
|
||||
|
||||
/*
|
||||
* We keep a little list of ref counted metadata objects to prevent two
|
||||
* different target instances creating separate bufio instances. This is
|
||||
* an issue if a table is reloaded before the suspend.
|
||||
*/
|
||||
static DEFINE_MUTEX(table_lock);
|
||||
static LIST_HEAD(table);
|
||||
|
||||
static struct dm_cache_metadata *lookup(struct block_device *bdev)
|
||||
{
|
||||
struct dm_cache_metadata *cmd;
|
||||
|
||||
list_for_each_entry(cmd, &table, list)
|
||||
if (cmd->bdev == bdev) {
|
||||
atomic_inc(&cmd->ref_count);
|
||||
return cmd;
|
||||
}
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static struct dm_cache_metadata *lookup_or_open(struct block_device *bdev,
|
||||
sector_t data_block_size,
|
||||
bool may_format_device,
|
||||
size_t policy_hint_size)
|
||||
{
|
||||
struct dm_cache_metadata *cmd, *cmd2;
|
||||
|
||||
mutex_lock(&table_lock);
|
||||
cmd = lookup(bdev);
|
||||
mutex_unlock(&table_lock);
|
||||
|
||||
if (cmd)
|
||||
return cmd;
|
||||
|
||||
cmd = metadata_open(bdev, data_block_size, may_format_device, policy_hint_size);
|
||||
if (cmd) {
|
||||
mutex_lock(&table_lock);
|
||||
cmd2 = lookup(bdev);
|
||||
if (cmd2) {
|
||||
mutex_unlock(&table_lock);
|
||||
__destroy_persistent_data_objects(cmd);
|
||||
kfree(cmd);
|
||||
return cmd2;
|
||||
}
|
||||
list_add(&cmd->list, &table);
|
||||
mutex_unlock(&table_lock);
|
||||
}
|
||||
|
||||
return cmd;
|
||||
}
|
||||
|
||||
static bool same_params(struct dm_cache_metadata *cmd, sector_t data_block_size)
|
||||
{
|
||||
if (cmd->data_block_size != data_block_size) {
|
||||
DMERR("data_block_size (%llu) different from that in metadata (%llu)\n",
|
||||
(unsigned long long) data_block_size,
|
||||
(unsigned long long) cmd->data_block_size);
|
||||
return false;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
|
||||
sector_t data_block_size,
|
||||
bool may_format_device,
|
||||
size_t policy_hint_size)
|
||||
{
|
||||
struct dm_cache_metadata *cmd = lookup_or_open(bdev, data_block_size,
|
||||
may_format_device, policy_hint_size);
|
||||
if (cmd && !same_params(cmd, data_block_size)) {
|
||||
dm_cache_metadata_close(cmd);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
return cmd;
|
||||
}
|
||||
|
||||
void dm_cache_metadata_close(struct dm_cache_metadata *cmd)
|
||||
{
|
||||
__destroy_persistent_data_objects(cmd);
|
||||
kfree(cmd);
|
||||
if (atomic_dec_and_test(&cmd->ref_count)) {
|
||||
mutex_lock(&table_lock);
|
||||
list_del(&cmd->list);
|
||||
mutex_unlock(&table_lock);
|
||||
|
||||
__destroy_persistent_data_objects(cmd);
|
||||
kfree(cmd);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
|||
|
|
@ -221,7 +221,13 @@ struct cache {
|
|||
struct list_head need_commit_migrations;
|
||||
sector_t migration_threshold;
|
||||
wait_queue_head_t migration_wait;
|
||||
atomic_t nr_migrations;
|
||||
atomic_t nr_allocated_migrations;
|
||||
|
||||
/*
|
||||
* The number of in flight migrations that are performing
|
||||
* background io. eg, promotion, writeback.
|
||||
*/
|
||||
atomic_t nr_io_migrations;
|
||||
|
||||
wait_queue_head_t quiescing_wait;
|
||||
atomic_t quiescing;
|
||||
|
|
@ -258,7 +264,6 @@ struct cache {
|
|||
struct dm_deferred_set *all_io_ds;
|
||||
|
||||
mempool_t *migration_pool;
|
||||
struct dm_cache_migration *next_migration;
|
||||
|
||||
struct dm_cache_policy *policy;
|
||||
unsigned policy_nr_args;
|
||||
|
|
@ -350,10 +355,31 @@ static void free_prison_cell(struct cache *cache, struct dm_bio_prison_cell *cel
|
|||
dm_bio_prison_free_cell(cache->prison, cell);
|
||||
}
|
||||
|
||||
static struct dm_cache_migration *alloc_migration(struct cache *cache)
|
||||
{
|
||||
struct dm_cache_migration *mg;
|
||||
|
||||
mg = mempool_alloc(cache->migration_pool, GFP_NOWAIT);
|
||||
if (mg) {
|
||||
mg->cache = cache;
|
||||
atomic_inc(&mg->cache->nr_allocated_migrations);
|
||||
}
|
||||
|
||||
return mg;
|
||||
}
|
||||
|
||||
static void free_migration(struct dm_cache_migration *mg)
|
||||
{
|
||||
if (atomic_dec_and_test(&mg->cache->nr_allocated_migrations))
|
||||
wake_up(&mg->cache->migration_wait);
|
||||
|
||||
mempool_free(mg, mg->cache->migration_pool);
|
||||
}
|
||||
|
||||
static int prealloc_data_structs(struct cache *cache, struct prealloc *p)
|
||||
{
|
||||
if (!p->mg) {
|
||||
p->mg = mempool_alloc(cache->migration_pool, GFP_NOWAIT);
|
||||
p->mg = alloc_migration(cache);
|
||||
if (!p->mg)
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
|
@ -382,7 +408,7 @@ static void prealloc_free_structs(struct cache *cache, struct prealloc *p)
|
|||
free_prison_cell(cache, p->cell1);
|
||||
|
||||
if (p->mg)
|
||||
mempool_free(p->mg, cache->migration_pool);
|
||||
free_migration(p->mg);
|
||||
}
|
||||
|
||||
static struct dm_cache_migration *prealloc_get_migration(struct prealloc *p)
|
||||
|
|
@ -854,24 +880,14 @@ static void remap_to_origin_then_cache(struct cache *cache, struct bio *bio,
|
|||
* Migration covers moving data from the origin device to the cache, or
|
||||
* vice versa.
|
||||
*--------------------------------------------------------------*/
|
||||
static void free_migration(struct dm_cache_migration *mg)
|
||||
static void inc_io_migrations(struct cache *cache)
|
||||
{
|
||||
mempool_free(mg, mg->cache->migration_pool);
|
||||
atomic_inc(&cache->nr_io_migrations);
|
||||
}
|
||||
|
||||
static void inc_nr_migrations(struct cache *cache)
|
||||
static void dec_io_migrations(struct cache *cache)
|
||||
{
|
||||
atomic_inc(&cache->nr_migrations);
|
||||
}
|
||||
|
||||
static void dec_nr_migrations(struct cache *cache)
|
||||
{
|
||||
atomic_dec(&cache->nr_migrations);
|
||||
|
||||
/*
|
||||
* Wake the worker in case we're suspending the target.
|
||||
*/
|
||||
wake_up(&cache->migration_wait);
|
||||
atomic_dec(&cache->nr_io_migrations);
|
||||
}
|
||||
|
||||
static void __cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell,
|
||||
|
|
@ -894,11 +910,10 @@ static void cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell,
|
|||
wake_worker(cache);
|
||||
}
|
||||
|
||||
static void cleanup_migration(struct dm_cache_migration *mg)
|
||||
static void free_io_migration(struct dm_cache_migration *mg)
|
||||
{
|
||||
struct cache *cache = mg->cache;
|
||||
dec_io_migrations(mg->cache);
|
||||
free_migration(mg);
|
||||
dec_nr_migrations(cache);
|
||||
}
|
||||
|
||||
static void migration_failure(struct dm_cache_migration *mg)
|
||||
|
|
@ -923,7 +938,7 @@ static void migration_failure(struct dm_cache_migration *mg)
|
|||
cell_defer(cache, mg->new_ocell, true);
|
||||
}
|
||||
|
||||
cleanup_migration(mg);
|
||||
free_io_migration(mg);
|
||||
}
|
||||
|
||||
static void migration_success_pre_commit(struct dm_cache_migration *mg)
|
||||
|
|
@ -934,7 +949,7 @@ static void migration_success_pre_commit(struct dm_cache_migration *mg)
|
|||
if (mg->writeback) {
|
||||
clear_dirty(cache, mg->old_oblock, mg->cblock);
|
||||
cell_defer(cache, mg->old_ocell, false);
|
||||
cleanup_migration(mg);
|
||||
free_io_migration(mg);
|
||||
return;
|
||||
|
||||
} else if (mg->demote) {
|
||||
|
|
@ -944,14 +959,14 @@ static void migration_success_pre_commit(struct dm_cache_migration *mg)
|
|||
mg->old_oblock);
|
||||
if (mg->promote)
|
||||
cell_defer(cache, mg->new_ocell, true);
|
||||
cleanup_migration(mg);
|
||||
free_io_migration(mg);
|
||||
return;
|
||||
}
|
||||
} else {
|
||||
if (dm_cache_insert_mapping(cache->cmd, mg->cblock, mg->new_oblock)) {
|
||||
DMWARN_LIMIT("promotion failed; couldn't update on disk metadata");
|
||||
policy_remove_mapping(cache->policy, mg->new_oblock);
|
||||
cleanup_migration(mg);
|
||||
free_io_migration(mg);
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
|
@ -984,7 +999,7 @@ static void migration_success_post_commit(struct dm_cache_migration *mg)
|
|||
} else {
|
||||
if (mg->invalidate)
|
||||
policy_remove_mapping(cache->policy, mg->old_oblock);
|
||||
cleanup_migration(mg);
|
||||
free_io_migration(mg);
|
||||
}
|
||||
|
||||
} else {
|
||||
|
|
@ -999,7 +1014,7 @@ static void migration_success_post_commit(struct dm_cache_migration *mg)
|
|||
bio_endio(mg->new_ocell->holder, 0);
|
||||
cell_defer(cache, mg->new_ocell, false);
|
||||
}
|
||||
cleanup_migration(mg);
|
||||
free_io_migration(mg);
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -1251,7 +1266,7 @@ static void promote(struct cache *cache, struct prealloc *structs,
|
|||
mg->new_ocell = cell;
|
||||
mg->start_jiffies = jiffies;
|
||||
|
||||
inc_nr_migrations(cache);
|
||||
inc_io_migrations(cache);
|
||||
quiesce_migration(mg);
|
||||
}
|
||||
|
||||
|
|
@ -1275,7 +1290,7 @@ static void writeback(struct cache *cache, struct prealloc *structs,
|
|||
mg->new_ocell = NULL;
|
||||
mg->start_jiffies = jiffies;
|
||||
|
||||
inc_nr_migrations(cache);
|
||||
inc_io_migrations(cache);
|
||||
quiesce_migration(mg);
|
||||
}
|
||||
|
||||
|
|
@ -1302,7 +1317,7 @@ static void demote_then_promote(struct cache *cache, struct prealloc *structs,
|
|||
mg->new_ocell = new_ocell;
|
||||
mg->start_jiffies = jiffies;
|
||||
|
||||
inc_nr_migrations(cache);
|
||||
inc_io_migrations(cache);
|
||||
quiesce_migration(mg);
|
||||
}
|
||||
|
||||
|
|
@ -1330,7 +1345,7 @@ static void invalidate(struct cache *cache, struct prealloc *structs,
|
|||
mg->new_ocell = NULL;
|
||||
mg->start_jiffies = jiffies;
|
||||
|
||||
inc_nr_migrations(cache);
|
||||
inc_io_migrations(cache);
|
||||
quiesce_migration(mg);
|
||||
}
|
||||
|
||||
|
|
@ -1412,7 +1427,7 @@ static void process_discard_bio(struct cache *cache, struct prealloc *structs,
|
|||
|
||||
static bool spare_migration_bandwidth(struct cache *cache)
|
||||
{
|
||||
sector_t current_volume = (atomic_read(&cache->nr_migrations) + 1) *
|
||||
sector_t current_volume = (atomic_read(&cache->nr_io_migrations) + 1) *
|
||||
cache->sectors_per_block;
|
||||
return current_volume < cache->migration_threshold;
|
||||
}
|
||||
|
|
@ -1764,7 +1779,7 @@ static void stop_quiescing(struct cache *cache)
|
|||
|
||||
static void wait_for_migrations(struct cache *cache)
|
||||
{
|
||||
wait_event(cache->migration_wait, !atomic_read(&cache->nr_migrations));
|
||||
wait_event(cache->migration_wait, !atomic_read(&cache->nr_allocated_migrations));
|
||||
}
|
||||
|
||||
static void stop_worker(struct cache *cache)
|
||||
|
|
@ -1876,9 +1891,6 @@ static void destroy(struct cache *cache)
|
|||
{
|
||||
unsigned i;
|
||||
|
||||
if (cache->next_migration)
|
||||
mempool_free(cache->next_migration, cache->migration_pool);
|
||||
|
||||
if (cache->migration_pool)
|
||||
mempool_destroy(cache->migration_pool);
|
||||
|
||||
|
|
@ -2424,7 +2436,8 @@ static int cache_create(struct cache_args *ca, struct cache **result)
|
|||
INIT_LIST_HEAD(&cache->quiesced_migrations);
|
||||
INIT_LIST_HEAD(&cache->completed_migrations);
|
||||
INIT_LIST_HEAD(&cache->need_commit_migrations);
|
||||
atomic_set(&cache->nr_migrations, 0);
|
||||
atomic_set(&cache->nr_allocated_migrations, 0);
|
||||
atomic_set(&cache->nr_io_migrations, 0);
|
||||
init_waitqueue_head(&cache->migration_wait);
|
||||
|
||||
init_waitqueue_head(&cache->quiescing_wait);
|
||||
|
|
@ -2487,8 +2500,6 @@ static int cache_create(struct cache_args *ca, struct cache **result)
|
|||
goto bad;
|
||||
}
|
||||
|
||||
cache->next_migration = NULL;
|
||||
|
||||
cache->need_tick_bio = true;
|
||||
cache->sized = false;
|
||||
cache->invalidate = false;
|
||||
|
|
|
|||
|
|
@ -206,6 +206,9 @@ struct mapped_device {
|
|||
/* zero-length flush that will be cloned and submitted to targets */
|
||||
struct bio flush_bio;
|
||||
|
||||
/* the number of internal suspends */
|
||||
unsigned internal_suspend_count;
|
||||
|
||||
struct dm_stats stats;
|
||||
};
|
||||
|
||||
|
|
@ -2928,7 +2931,7 @@ static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_fla
|
|||
{
|
||||
struct dm_table *map = NULL;
|
||||
|
||||
if (dm_suspended_internally_md(md))
|
||||
if (md->internal_suspend_count++)
|
||||
return; /* nested internal suspend */
|
||||
|
||||
if (dm_suspended_md(md)) {
|
||||
|
|
@ -2953,7 +2956,9 @@ static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_fla
|
|||
|
||||
static void __dm_internal_resume(struct mapped_device *md)
|
||||
{
|
||||
if (!dm_suspended_internally_md(md))
|
||||
BUG_ON(!md->internal_suspend_count);
|
||||
|
||||
if (--md->internal_suspend_count)
|
||||
return; /* resume from nested internal suspend */
|
||||
|
||||
if (dm_suspended_md(md))
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче