diff options
Diffstat (limited to 'drivers/md/dm-cache-metadata.c')
| -rw-r--r-- | drivers/md/dm-cache-metadata.c | 133 |
1 files changed, 114 insertions, 19 deletions
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index c1c0104..20cc36b 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -39,6 +39,8 @@ enum superblock_flag_bits { /* for spotting crashes that would invalidate the dirty bitset */ CLEAN_SHUTDOWN, + /* metadata must be checked using the tools */ + NEEDS_CHECK, }; /* @@ -107,6 +109,7 @@ struct dm_cache_metadata { struct dm_disk_bitset discard_info; struct rw_semaphore root_lock; + unsigned long flags; dm_block_t root; dm_block_t hint_root; dm_block_t discard_root; @@ -129,6 +132,14 @@ struct dm_cache_metadata { * buffer before the superblock is locked and updated. */ __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE]; + + /* + * Set if a transaction has to be aborted but the attempt to roll + * back to the previous (good) transaction failed. The only + * metadata operation permissible in this state is the closing of + * the device. + */ + bool fail_io:1; }; /*------------------------------------------------------------------- @@ -527,6 +538,7 @@ static unsigned long clear_clean_shutdown(unsigned long flags) static void read_superblock_fields(struct dm_cache_metadata *cmd, struct cache_disk_superblock *disk_super) { + cmd->flags = le32_to_cpu(disk_super->flags); cmd->root = le64_to_cpu(disk_super->mapping_root); cmd->hint_root = le64_to_cpu(disk_super->hint_root); cmd->discard_root = le64_to_cpu(disk_super->discard_root); @@ -625,6 +637,7 @@ static int __commit_transaction(struct dm_cache_metadata *cmd, if (mutator) update_flags(disk_super, mutator); + disk_super->flags = cpu_to_le32(cmd->flags); disk_super->mapping_root = cpu_to_le64(cmd->root); disk_super->hint_root = cpu_to_le64(cmd->hint_root); disk_super->discard_root = cpu_to_le64(cmd->discard_root); @@ -693,6 +706,7 @@ static struct dm_cache_metadata *metadata_open(struct block_device *bdev, cmd->cache_blocks = 0; cmd->policy_hint_size = policy_hint_size; cmd->changed = true; + cmd->fail_io = false; r = __create_persistent_data_objects(cmd, may_format_device); if (r) { @@ -796,7 +810,8 @@ void dm_cache_metadata_close(struct dm_cache_metadata *cmd) list_del(&cmd->list); mutex_unlock(&table_lock); - __destroy_persistent_data_objects(cmd); + if (!cmd->fail_io) + __destroy_persistent_data_objects(cmd); kfree(cmd); } } @@ -848,13 +863,26 @@ static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd, return 0; } +#define WRITE_LOCK(cmd) \ + if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) \ + return -EINVAL; \ + down_write(&cmd->root_lock) + +#define WRITE_LOCK_VOID(cmd) \ + if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) \ + return; \ + down_write(&cmd->root_lock) + +#define WRITE_UNLOCK(cmd) \ + up_write(&cmd->root_lock) + int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) { int r; bool clean; __le64 null_mapping = pack_value(0, 0); - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); __dm_bless_for_disk(&null_mapping); if (from_cblock(new_cache_size) < from_cblock(cmd->cache_blocks)) { @@ -880,7 +908,7 @@ int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) cmd->changed = true; out: - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -891,7 +919,7 @@ int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, { int r; - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = dm_bitset_resize(&cmd->discard_info, cmd->discard_root, from_dblock(cmd->discard_nr_blocks), @@ -903,7 +931,7 @@ int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, } cmd->changed = true; - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -946,9 +974,9 @@ int dm_cache_set_discard(struct dm_cache_metadata *cmd, { int r; - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = __discard(cmd, dblock, discard); - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -1020,9 +1048,9 @@ int dm_cache_remove_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock) { int r; - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = __remove(cmd, cblock); - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -1048,9 +1076,9 @@ int dm_cache_insert_mapping(struct dm_cache_metadata *cmd, { int r; - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = __insert(cmd, cblock, oblock); - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -1234,9 +1262,9 @@ int dm_cache_set_dirty(struct dm_cache_metadata *cmd, { int r; - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = __dirty(cmd, cblock, dirty); - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -1252,9 +1280,9 @@ void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd, void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd, struct dm_cache_statistics *stats) { - down_write(&cmd->root_lock); + WRITE_LOCK_VOID(cmd); cmd->stats = *stats; - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); } int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown) @@ -1263,7 +1291,7 @@ int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown) flags_mutator mutator = (clean_shutdown ? set_clean_shutdown : clear_clean_shutdown); - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = __commit_transaction(cmd, mutator); if (r) goto out; @@ -1271,7 +1299,7 @@ int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown) r = __begin_transaction(cmd); out: - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -1376,9 +1404,9 @@ int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy * { int r; - down_write(&cmd->root_lock); + WRITE_LOCK(cmd); r = write_hints(cmd, policy); - up_write(&cmd->root_lock); + WRITE_UNLOCK(cmd); return r; } @@ -1387,3 +1415,70 @@ int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result) { return blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result); } + +void dm_cache_metadata_set_read_only(struct dm_cache_metadata *cmd) +{ + WRITE_LOCK_VOID(cmd); + dm_bm_set_read_only(cmd->bm); + WRITE_UNLOCK(cmd); +} + +void dm_cache_metadata_set_read_write(struct dm_cache_metadata *cmd) +{ + WRITE_LOCK_VOID(cmd); + dm_bm_set_read_write(cmd->bm); + WRITE_UNLOCK(cmd); +} + +int dm_cache_metadata_set_needs_check(struct dm_cache_metadata *cmd) +{ + int r; + struct dm_block *sblock; + struct cache_disk_superblock *disk_super; + + /* + * We ignore fail_io for this function. + */ + down_write(&cmd->root_lock); + set_bit(NEEDS_CHECK, &cmd->flags); + + r = superblock_lock(cmd, &sblock); + if (r) { + DMERR("couldn't read superblock"); + goto out; + } + + disk_super = dm_block_data(sblock); + disk_super->flags = cpu_to_le32(cmd->flags); + + dm_bm_unlock(sblock); + +out: + up_write(&cmd->root_lock); + return r; +} + +bool dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd) +{ + bool needs_check; + + down_read(&cmd->root_lock); + needs_check = !!test_bit(NEEDS_CHECK, &cmd->flags); + up_read(&cmd->root_lock); + + return needs_check; +} + +int dm_cache_metadata_abort(struct dm_cache_metadata *cmd) +{ + int r; + + WRITE_LOCK(cmd); + __destroy_persistent_data_objects(cmd); + r = __create_persistent_data_objects(cmd, false); + if (r) + cmd->fail_io = true; + WRITE_UNLOCK(cmd); + + return r; +} |
