diff --git a/Documentation/device-mapper/cache.txt b/Documentation/device-mapper/cache.txt index 68c0f517c60e..82960cffbad3 100644 --- a/Documentation/device-mapper/cache.txt +++ b/Documentation/device-mapper/cache.txt @@ -221,6 +221,7 @@ Status <#read hits> <#read misses> <#write hits> <#write misses> <#demotions> <#promotions> <#dirty> <#features> * <#core args> * <#policy args> * + metadata block size : Fixed block size for each metadata block in sectors @@ -251,8 +252,12 @@ core args : Key/value pairs for tuning the core e.g. migration_threshold policy name : Name of the policy #policy args : Number of policy arguments to follow (must be even) -policy args : Key/value pairs - e.g. sequential_threshold +policy args : Key/value pairs e.g. sequential_threshold +cache metadata mode : ro if read-only, rw if read-write + In serious cases where even a read-only mode is deemed unsafe + no further I/O will be permitted and the status will just + contain the string 'Fail'. The userspace recovery tools + should then be used. Messages -------- diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index c1c010498a21..20cc36b01b77 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; +} diff --git a/drivers/md/dm-cache-metadata.h b/drivers/md/dm-cache-metadata.h index 4ecc403be283..2ffee21f318d 100644 --- a/drivers/md/dm-cache-metadata.h +++ b/drivers/md/dm-cache-metadata.h @@ -102,6 +102,10 @@ struct dm_cache_statistics { void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd, struct dm_cache_statistics *stats); + +/* + * 'void' because it's no big deal if it fails. + */ void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd, struct dm_cache_statistics *stats); @@ -133,6 +137,12 @@ int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy * */ int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result); +bool dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd); +int dm_cache_metadata_set_needs_check(struct dm_cache_metadata *cmd); +void dm_cache_metadata_set_read_only(struct dm_cache_metadata *cmd); +void dm_cache_metadata_set_read_write(struct dm_cache_metadata *cmd); +int dm_cache_metadata_abort(struct dm_cache_metadata *cmd); + /*----------------------------------------------------------------*/ #endif /* DM_CACHE_METADATA_H */ diff --git a/drivers/md/dm-cache-policy-internal.h b/drivers/md/dm-cache-policy-internal.h index 9dc05a52369e..ccbe852d5362 100644 --- a/drivers/md/dm-cache-policy-internal.h +++ b/drivers/md/dm-cache-policy-internal.h @@ -89,13 +89,15 @@ static inline void policy_tick(struct dm_cache_policy *p) return p->tick(p); } -static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen) +static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, + unsigned maxlen, ssize_t *sz_ptr) { - ssize_t sz = 0; + ssize_t sz = *sz_ptr; if (p->emit_config_values) - return p->emit_config_values(p, result, maxlen); + return p->emit_config_values(p, result, maxlen, sz_ptr); - DMEMIT("0"); + DMEMIT("0 "); + *sz_ptr = sz; return 0; } diff --git a/drivers/md/dm-cache-policy-mq.c b/drivers/md/dm-cache-policy-mq.c index 7cbae125879c..084eec653321 100644 --- a/drivers/md/dm-cache-policy-mq.c +++ b/drivers/md/dm-cache-policy-mq.c @@ -1323,22 +1323,24 @@ static int mq_set_config_value(struct dm_cache_policy *p, return 0; } -static int mq_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen) +static int mq_emit_config_values(struct dm_cache_policy *p, char *result, + unsigned maxlen, ssize_t *sz_ptr) { - ssize_t sz = 0; + ssize_t sz = *sz_ptr; struct mq_policy *mq = to_mq_policy(p); DMEMIT("10 random_threshold %u " "sequential_threshold %u " "discard_promote_adjustment %u " "read_promote_adjustment %u " - "write_promote_adjustment %u", + "write_promote_adjustment %u ", mq->tracker.thresholds[PATTERN_RANDOM], mq->tracker.thresholds[PATTERN_SEQUENTIAL], mq->discard_promote_adjustment, mq->read_promote_adjustment, mq->write_promote_adjustment); + *sz_ptr = sz; return 0; } diff --git a/drivers/md/dm-cache-policy.h b/drivers/md/dm-cache-policy.h index 6106ca3aa350..74709129d856 100644 --- a/drivers/md/dm-cache-policy.h +++ b/drivers/md/dm-cache-policy.h @@ -208,8 +208,8 @@ struct dm_cache_policy { /* * Configuration. */ - int (*emit_config_values)(struct dm_cache_policy *p, - char *result, unsigned maxlen); + int (*emit_config_values)(struct dm_cache_policy *p, char *result, + unsigned maxlen, ssize_t *sz_ptr); int (*set_config_value)(struct dm_cache_policy *p, const char *key, const char *value); diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 6d36ed3c46a0..dae0321ebfa9 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -150,12 +150,10 @@ static void dm_unhook_bio(struct dm_hook_info *h, struct bio *bio) #define DATA_DEV_BLOCK_SIZE_MIN_SECTORS (32 * 1024 >> SECTOR_SHIFT) #define DATA_DEV_BLOCK_SIZE_MAX_SECTORS (1024 * 1024 * 1024 >> SECTOR_SHIFT) -/* - * FIXME: the cache is read/write for the time being. - */ enum cache_metadata_mode { CM_WRITE, /* metadata may be changed */ CM_READ_ONLY, /* metadata may not be changed */ + CM_FAIL }; enum cache_io_mode { @@ -385,6 +383,8 @@ struct prealloc { struct dm_bio_prison_cell *cell2; }; +static enum cache_metadata_mode get_cache_mode(struct cache *cache); + static void wake_worker(struct cache *cache) { queue_work(cache->wq, &cache->worker); @@ -699,6 +699,9 @@ static void save_stats(struct cache *cache) { struct dm_cache_statistics stats; + if (get_cache_mode(cache) >= CM_READ_ONLY) + return; + stats.read_hits = atomic_read(&cache->stats.read_hit); stats.read_misses = atomic_read(&cache->stats.read_miss); stats.write_hits = atomic_read(&cache->stats.write_hit); @@ -957,6 +960,84 @@ static void remap_to_origin_then_cache(struct cache *cache, struct bio *bio, remap_to_origin_clear_discard(pb->cache, bio, oblock); } +/*---------------------------------------------------------------- + * Failure modes + *--------------------------------------------------------------*/ +static enum cache_metadata_mode get_cache_mode(struct cache *cache) +{ + return cache->features.mode; +} + +static void notify_mode_switch(struct cache *cache, enum cache_metadata_mode mode) +{ + const char *descs[] = { + "write", + "read-only", + "fail" + }; + + dm_table_event(cache->ti->table); + DMINFO("switching cache to %s mode", descs[(int)mode]); +} + +static void set_cache_mode(struct cache *cache, enum cache_metadata_mode new_mode) +{ + bool needs_check = dm_cache_metadata_needs_check(cache->cmd); + enum cache_metadata_mode old_mode = get_cache_mode(cache); + + if (new_mode == CM_WRITE && needs_check) { + DMERR("unable to switch cache to write mode until repaired."); + if (old_mode != new_mode) + new_mode = old_mode; + else + new_mode = CM_READ_ONLY; + } + + /* Never move out of fail mode */ + if (old_mode == CM_FAIL) + new_mode = CM_FAIL; + + switch (new_mode) { + case CM_FAIL: + case CM_READ_ONLY: + dm_cache_metadata_set_read_only(cache->cmd); + break; + + case CM_WRITE: + dm_cache_metadata_set_read_write(cache->cmd); + break; + } + + cache->features.mode = new_mode; + + if (new_mode != old_mode) + notify_mode_switch(cache, new_mode); +} + +static void abort_transaction(struct cache *cache) +{ + if (get_cache_mode(cache) >= CM_READ_ONLY) + return; + + if (dm_cache_metadata_set_needs_check(cache->cmd)) { + DMERR("failed to set 'needs_check' flag in metadata"); + set_cache_mode(cache, CM_FAIL); + } + + DMERR_LIMIT("aborting current metadata transaction"); + if (dm_cache_metadata_abort(cache->cmd)) { + DMERR("failed to abort metadata transaction"); + set_cache_mode(cache, CM_FAIL); + } +} + +static void metadata_operation_failed(struct cache *cache, const char *op, int r) +{ + DMERR_LIMIT("metadata operation '%s' failed: error = %d", op, r); + abort_transaction(cache); + set_cache_mode(cache, CM_READ_ONLY); +} + /*---------------------------------------------------------------- * Migration processing * @@ -1063,6 +1144,7 @@ static void migration_failure(struct dm_cache_migration *mg) static void migration_success_pre_commit(struct dm_cache_migration *mg) { + int r; unsigned long flags; struct cache *cache = mg->cache; @@ -1073,8 +1155,10 @@ static void migration_success_pre_commit(struct dm_cache_migration *mg) return; } else if (mg->demote) { - if (dm_cache_remove_mapping(cache->cmd, mg->cblock)) { + r = dm_cache_remove_mapping(cache->cmd, mg->cblock); + if (r) { DMWARN_LIMIT("demotion failed; couldn't update on disk metadata"); + metadata_operation_failed(cache, "dm_cache_remove_mapping", r); policy_force_mapping(cache->policy, mg->new_oblock, mg->old_oblock); if (mg->promote) @@ -1083,8 +1167,10 @@ static void migration_success_pre_commit(struct dm_cache_migration *mg) return; } } else { - if (dm_cache_insert_mapping(cache->cmd, mg->cblock, mg->new_oblock)) { + r = dm_cache_insert_mapping(cache->cmd, mg->cblock, mg->new_oblock); + if (r) { DMWARN_LIMIT("promotion failed; couldn't update on disk metadata"); + metadata_operation_failed(cache, "dm_cache_insert_mapping", r); policy_remove_mapping(cache->policy, mg->new_oblock); free_io_migration(mg); return; @@ -1812,15 +1898,32 @@ static int need_commit_due_to_time(struct cache *cache) jiffies > cache->last_commit_jiffies + COMMIT_PERIOD; } +/* + * A non-zero return indicates read_only or fail_io mode. + */ +static int commit(struct cache *cache, bool clean_shutdown) +{ + int r; + + if (get_cache_mode(cache) >= CM_READ_ONLY) + return -EINVAL; + + atomic_inc(&cache->stats.commit_count); + r = dm_cache_commit(cache->cmd, clean_shutdown); + if (r) + metadata_operation_failed(cache, "dm_cache_commit", r); + + return r; +} + static int commit_if_needed(struct cache *cache) { int r = 0; if ((cache->commit_requested || need_commit_due_to_time(cache)) && dm_cache_changed_this_transaction(cache->cmd)) { - atomic_inc(&cache->stats.commit_count); + r = commit(cache, false); cache->commit_requested = false; - r = dm_cache_commit(cache->cmd, false); cache->last_commit_jiffies = jiffies; } @@ -1988,8 +2091,10 @@ static void process_invalidation_request(struct cache *cache, struct invalidatio r = policy_remove_cblock(cache->policy, to_cblock(begin)); if (!r) { r = dm_cache_remove_mapping(cache->cmd, to_cblock(begin)); - if (r) + if (r) { + metadata_operation_failed(cache, "dm_cache_remove_mapping", r); break; + } } else if (r == -ENODATA) { /* harmless, already unmapped */ @@ -2133,12 +2238,6 @@ static void do_worker(struct work_struct *ws) if (commit_if_needed(cache)) { process_deferred_flush_bios(cache, false); process_migrations(cache, &cache->need_commit_migrations, migration_failure); - - /* - * FIXME: rollback metadata or just go into a - * failure mode and error everything - */ - } else { process_deferred_flush_bios(cache, true); process_migrations(cache, &cache->need_commit_migrations, @@ -2711,6 +2810,12 @@ static int cache_create(struct cache_args *ca, struct cache **result) goto bad; } cache->cmd = cmd; + set_cache_mode(cache, CM_WRITE); + if (get_cache_mode(cache) != CM_WRITE) { + *error = "Unable to get write access to metadata, please check/repair metadata."; + r = -EINVAL; + goto bad; + } if (passthrough_mode(&cache->features)) { bool all_clean; @@ -3043,11 +3148,16 @@ static int write_dirty_bitset(struct cache *cache) { unsigned i, r; + if (get_cache_mode(cache) >= CM_READ_ONLY) + return -EINVAL; + for (i = 0; i < from_cblock(cache->cache_size); i++) { r = dm_cache_set_dirty(cache->cmd, to_cblock(i), is_dirty(cache, to_cblock(i))); - if (r) + if (r) { + metadata_operation_failed(cache, "dm_cache_set_dirty", r); return r; + } } return 0; @@ -3057,18 +3167,40 @@ static int write_discard_bitset(struct cache *cache) { unsigned i, r; + if (get_cache_mode(cache) >= CM_READ_ONLY) + return -EINVAL; + r = dm_cache_discard_bitset_resize(cache->cmd, cache->discard_block_size, cache->discard_nr_blocks); if (r) { DMERR("could not resize on-disk discard bitset"); + metadata_operation_failed(cache, "dm_cache_discard_bitset_resize", r); return r; } for (i = 0; i < from_dblock(cache->discard_nr_blocks); i++) { r = dm_cache_set_discard(cache->cmd, to_dblock(i), is_discarded(cache, to_dblock(i))); - if (r) + if (r) { + metadata_operation_failed(cache, "dm_cache_set_discard", r); return r; + } + } + + return 0; +} + +static int write_hints(struct cache *cache) +{ + int r; + + if (get_cache_mode(cache) >= CM_READ_ONLY) + return -EINVAL; + + r = dm_cache_write_hints(cache->cmd, cache->policy); + if (r) { + metadata_operation_failed(cache, "dm_cache_write_hints", r); + return r; } return 0; @@ -3091,7 +3223,7 @@ static bool sync_metadata(struct cache *cache) save_stats(cache); - r3 = dm_cache_write_hints(cache->cmd, cache->policy); + r3 = write_hints(cache); if (r3) DMERR("could not write hints"); @@ -3100,9 +3232,9 @@ static bool sync_metadata(struct cache *cache) * set the clean shutdown flag. This will effectively force every * dirty bit to be set on reload. */ - r4 = dm_cache_commit(cache->cmd, !r1 && !r2 && !r3); + r4 = commit(cache, !r1 && !r2 && !r3); if (r4) - DMERR("could not write cache metadata. Data loss may occur."); + DMERR("could not write cache metadata."); return !r1 && !r2 && !r3 && !r4; } @@ -3118,7 +3250,8 @@ static void cache_postsuspend(struct dm_target *ti) requeue_deferred_cells(cache); stop_quiescing(cache); - (void) sync_metadata(cache); + if (get_cache_mode(cache) == CM_WRITE) + (void) sync_metadata(cache); } static int load_mapping(void *context, dm_oblock_t oblock, dm_cblock_t cblock, @@ -3257,6 +3390,7 @@ static int resize_cache_dev(struct cache *cache, dm_cblock_t new_size) r = dm_cache_resize(cache->cmd, new_size); if (r) { DMERR("could not resize cache metadata"); + metadata_operation_failed(cache, "dm_cache_resize", r); return r; } @@ -3295,6 +3429,7 @@ static int cache_preresume(struct dm_target *ti) load_mapping, cache); if (r) { DMERR("could not load cache mappings"); + metadata_operation_failed(cache, "dm_cache_load_mappings", r); return r; } @@ -3315,6 +3450,7 @@ static int cache_preresume(struct dm_target *ti) r = dm_cache_load_discards(cache->cmd, load_discard, &li); if (r) { DMERR("could not load origin discards"); + metadata_operation_failed(cache, "dm_cache_load_discards", r); return r; } set_discard_range(&li); @@ -3342,7 +3478,7 @@ static void cache_resume(struct dm_target *ti) * <#demotions> <#promotions> <#dirty> * <#features> * * <#core args> - * <#policy args> * + * <#policy args> * */ static void cache_status(struct dm_target *ti, status_type_t type, unsigned status_flags, char *result, unsigned maxlen) @@ -3358,13 +3494,15 @@ static void cache_status(struct dm_target *ti, status_type_t type, switch (type) { case STATUSTYPE_INFO: - /* Commit to ensure statistics aren't out-of-date */ - if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti)) { - r = dm_cache_commit(cache->cmd, false); - if (r) - DMERR("could not commit metadata for accurate status"); + if (get_cache_mode(cache) == CM_FAIL) { + DMEMIT("Fail"); + break; } + /* Commit to ensure statistics aren't out-of-date */ + if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti)) + (void) commit(cache, false); + r = dm_cache_get_free_metadata_block_count(cache->cmd, &nr_free_blocks_metadata); if (r) { @@ -3413,11 +3551,16 @@ static void cache_status(struct dm_target *ti, status_type_t type, DMEMIT("%s ", dm_cache_policy_get_name(cache->policy)); if (sz < maxlen) { - r = policy_emit_config_values(cache->policy, result + sz, maxlen - sz); + r = policy_emit_config_values(cache->policy, result, maxlen, &sz); if (r) DMERR("policy_emit_config_values returned %d", r); } + if (get_cache_mode(cache) == CM_READ_ONLY) + DMEMIT("ro "); + else + DMEMIT("rw "); + break; case STATUSTYPE_TABLE: @@ -3573,6 +3716,11 @@ static int cache_message(struct dm_target *ti, unsigned argc, char **argv) if (!argc) return -EINVAL; + if (get_cache_mode(cache) >= CM_READ_ONLY) { + DMERR("unable to service cache target messages in READ_ONLY or FAIL mode"); + return -EOPNOTSUPP; + } + if (!strcasecmp(argv[0], "invalidate_cblocks")) return process_invalidate_cblocks_message(cache, argc - 1, (const char **) argv + 1); @@ -3646,7 +3794,7 @@ static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits) static struct target_type cache_target = { .name = "cache", - .version = {1, 6, 0}, + .version = {1, 7, 0}, .module = THIS_MODULE, .ctr = cache_ctr, .dtr = cache_dtr,