diff options
Diffstat (limited to 'drivers/md/dm-cache-metadata.c')
-rw-r--r-- | drivers/md/dm-cache-metadata.c | 64 |
1 files changed, 51 insertions, 13 deletions
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index fbd3625..83e995f 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -83,6 +83,8 @@ struct cache_disk_superblock { __le32 read_misses; __le32 write_hits; __le32 write_misses; + + __le32 policy_version[CACHE_POLICY_VERSION_SIZE]; } __packed; struct dm_cache_metadata { @@ -109,6 +111,7 @@ struct dm_cache_metadata { bool clean_when_opened:1; char policy_name[CACHE_POLICY_NAME_SIZE]; + unsigned policy_version[CACHE_POLICY_VERSION_SIZE]; size_t policy_hint_size; struct dm_cache_statistics stats; }; @@ -268,7 +271,8 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd) memset(disk_super->uuid, 0, sizeof(disk_super->uuid)); disk_super->magic = cpu_to_le64(CACHE_SUPERBLOCK_MAGIC); disk_super->version = cpu_to_le32(CACHE_VERSION); - memset(disk_super->policy_name, 0, CACHE_POLICY_NAME_SIZE); + memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name)); + memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version)); disk_super->policy_hint_size = 0; r = dm_sm_copy_root(cmd->metadata_sm, &disk_super->metadata_space_map_root, @@ -284,7 +288,6 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd) disk_super->metadata_block_size = cpu_to_le32(DM_CACHE_METADATA_BLOCK_SIZE >> SECTOR_SHIFT); disk_super->data_block_size = cpu_to_le32(cmd->data_block_size); disk_super->cache_blocks = cpu_to_le32(0); - memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name)); disk_super->read_hits = cpu_to_le32(0); disk_super->read_misses = cpu_to_le32(0); @@ -478,6 +481,9 @@ static void read_superblock_fields(struct dm_cache_metadata *cmd, cmd->data_block_size = le32_to_cpu(disk_super->data_block_size); cmd->cache_blocks = to_cblock(le32_to_cpu(disk_super->cache_blocks)); strncpy(cmd->policy_name, disk_super->policy_name, sizeof(cmd->policy_name)); + cmd->policy_version[0] = le32_to_cpu(disk_super->policy_version[0]); + cmd->policy_version[1] = le32_to_cpu(disk_super->policy_version[1]); + cmd->policy_version[2] = le32_to_cpu(disk_super->policy_version[2]); cmd->policy_hint_size = le32_to_cpu(disk_super->policy_hint_size); cmd->stats.read_hits = le32_to_cpu(disk_super->read_hits); @@ -572,6 +578,9 @@ static int __commit_transaction(struct dm_cache_metadata *cmd, disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks)); disk_super->cache_blocks = cpu_to_le32(from_cblock(cmd->cache_blocks)); strncpy(disk_super->policy_name, cmd->policy_name, sizeof(disk_super->policy_name)); + disk_super->policy_version[0] = cpu_to_le32(cmd->policy_version[0]); + disk_super->policy_version[1] = cpu_to_le32(cmd->policy_version[1]); + disk_super->policy_version[2] = cpu_to_le32(cmd->policy_version[2]); disk_super->read_hits = cpu_to_le32(cmd->stats.read_hits); disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses); @@ -854,18 +863,43 @@ struct thunk { bool hints_valid; }; +static bool policy_unchanged(struct dm_cache_metadata *cmd, + struct dm_cache_policy *policy) +{ + const char *policy_name = dm_cache_policy_get_name(policy); + const unsigned *policy_version = dm_cache_policy_get_version(policy); + size_t policy_hint_size = dm_cache_policy_get_hint_size(policy); + + /* + * Ensure policy names match. + */ + if (strncmp(cmd->policy_name, policy_name, sizeof(cmd->policy_name))) + return false; + + /* + * Ensure policy major versions match. + */ + if (cmd->policy_version[0] != policy_version[0]) + return false; + + /* + * Ensure policy hint sizes match. + */ + if (cmd->policy_hint_size != policy_hint_size) + return false; + + return true; +} + static bool hints_array_initialized(struct dm_cache_metadata *cmd) { return cmd->hint_root && cmd->policy_hint_size; } static bool hints_array_available(struct dm_cache_metadata *cmd, - const char *policy_name) + struct dm_cache_policy *policy) { - bool policy_names_match = !strncmp(cmd->policy_name, policy_name, - sizeof(cmd->policy_name)); - - return cmd->clean_when_opened && policy_names_match && + return cmd->clean_when_opened && policy_unchanged(cmd, policy) && hints_array_initialized(cmd); } @@ -899,7 +933,8 @@ static int __load_mapping(void *context, uint64_t cblock, void *leaf) return r; } -static int __load_mappings(struct dm_cache_metadata *cmd, const char *policy_name, +static int __load_mappings(struct dm_cache_metadata *cmd, + struct dm_cache_policy *policy, load_mapping_fn fn, void *context) { struct thunk thunk; @@ -909,18 +944,19 @@ static int __load_mappings(struct dm_cache_metadata *cmd, const char *policy_nam thunk.cmd = cmd; thunk.respect_dirty_flags = cmd->clean_when_opened; - thunk.hints_valid = hints_array_available(cmd, policy_name); + thunk.hints_valid = hints_array_available(cmd, policy); return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk); } -int dm_cache_load_mappings(struct dm_cache_metadata *cmd, const char *policy_name, +int dm_cache_load_mappings(struct dm_cache_metadata *cmd, + struct dm_cache_policy *policy, load_mapping_fn fn, void *context) { int r; down_read(&cmd->root_lock); - r = __load_mappings(cmd, policy_name, fn, context); + r = __load_mappings(cmd, policy, fn, context); up_read(&cmd->root_lock); return r; @@ -979,7 +1015,7 @@ static int __dirty(struct dm_cache_metadata *cmd, dm_cblock_t cblock, bool dirty /* nothing to be done */ return 0; - value = pack_value(oblock, flags | (dirty ? M_DIRTY : 0)); + value = pack_value(oblock, (flags & ~M_DIRTY) | (dirty ? M_DIRTY : 0)); __dm_bless_for_disk(&value); r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), @@ -1070,13 +1106,15 @@ static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *po __le32 value; size_t hint_size; const char *policy_name = dm_cache_policy_get_name(policy); + const unsigned *policy_version = dm_cache_policy_get_version(policy); if (!policy_name[0] || (strlen(policy_name) > sizeof(cmd->policy_name) - 1)) return -EINVAL; - if (strcmp(cmd->policy_name, policy_name)) { + if (!policy_unchanged(cmd, policy)) { strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name)); + memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version)); hint_size = dm_cache_policy_get_hint_size(policy); if (!hint_size) |