From 64ab346a360a4b15c28fb8531918d4a01f4eabd9 Mon Sep 17 00:00:00 2001 From: Heinz Mauelshagen Date: Thu, 27 Mar 2014 15:14:10 -0400 Subject: [PATCH] dm cache: remove remainder of distinct discard block size Discard block size not being equal to cache block size causes data corruption by erroneously avoiding migrations in issue_copy() because the discard state is being cleared for a group of cache blocks when it should not. Completely remove all code that enabled a distinction between the cache block size and discard block size. Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer --- drivers/md/dm-cache-block-types.h | 11 ----- drivers/md/dm-cache-metadata.c | 34 +++++++-------- drivers/md/dm-cache-metadata.h | 6 +-- drivers/md/dm-cache-target.c | 72 +++++++++++-------------------- 4 files changed, 46 insertions(+), 77 deletions(-) diff --git a/drivers/md/dm-cache-block-types.h b/drivers/md/dm-cache-block-types.h index bed4ad4e1b7c..aac0e2df06be 100644 --- a/drivers/md/dm-cache-block-types.h +++ b/drivers/md/dm-cache-block-types.h @@ -19,7 +19,6 @@ typedef dm_block_t __bitwise__ dm_oblock_t; typedef uint32_t __bitwise__ dm_cblock_t; -typedef dm_block_t __bitwise__ dm_dblock_t; static inline dm_oblock_t to_oblock(dm_block_t b) { @@ -41,14 +40,4 @@ static inline uint32_t from_cblock(dm_cblock_t b) return (__force uint32_t) b; } -static inline dm_dblock_t to_dblock(dm_block_t b) -{ - return (__force dm_dblock_t) b; -} - -static inline dm_block_t from_dblock(dm_dblock_t b) -{ - return (__force dm_block_t) b; -} - #endif /* DM_CACHE_BLOCK_TYPES_H */ diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index 9ef0752e8a08..cbd568a3a579 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -109,7 +109,7 @@ struct dm_cache_metadata { dm_block_t discard_root; sector_t discard_block_size; - dm_dblock_t discard_nr_blocks; + dm_oblock_t discard_nr_blocks; sector_t data_block_size; dm_cblock_t cache_blocks; @@ -302,7 +302,7 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd) disk_super->hint_root = cpu_to_le64(cmd->hint_root); disk_super->discard_root = cpu_to_le64(cmd->discard_root); disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); - disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks)); + disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(cmd->discard_nr_blocks)); 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); @@ -496,7 +496,7 @@ static void read_superblock_fields(struct dm_cache_metadata *cmd, cmd->hint_root = le64_to_cpu(disk_super->hint_root); cmd->discard_root = le64_to_cpu(disk_super->discard_root); cmd->discard_block_size = le64_to_cpu(disk_super->discard_block_size); - cmd->discard_nr_blocks = to_dblock(le64_to_cpu(disk_super->discard_nr_blocks)); + cmd->discard_nr_blocks = to_oblock(le64_to_cpu(disk_super->discard_nr_blocks)); 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)); @@ -594,7 +594,7 @@ static int __commit_transaction(struct dm_cache_metadata *cmd, disk_super->hint_root = cpu_to_le64(cmd->hint_root); disk_super->discard_root = cpu_to_le64(cmd->discard_root); disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); - disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks)); + disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(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]); @@ -771,15 +771,15 @@ out: int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, sector_t discard_block_size, - dm_dblock_t new_nr_entries) + dm_oblock_t new_nr_entries) { int r; down_write(&cmd->root_lock); r = dm_bitset_resize(&cmd->discard_info, cmd->discard_root, - from_dblock(cmd->discard_nr_blocks), - from_dblock(new_nr_entries), + from_oblock(cmd->discard_nr_blocks), + from_oblock(new_nr_entries), false, &cmd->discard_root); if (!r) { cmd->discard_block_size = discard_block_size; @@ -792,28 +792,28 @@ int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, return r; } -static int __set_discard(struct dm_cache_metadata *cmd, dm_dblock_t b) +static int __set_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) { return dm_bitset_set_bit(&cmd->discard_info, cmd->discard_root, - from_dblock(b), &cmd->discard_root); + from_oblock(b), &cmd->discard_root); } -static int __clear_discard(struct dm_cache_metadata *cmd, dm_dblock_t b) +static int __clear_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) { return dm_bitset_clear_bit(&cmd->discard_info, cmd->discard_root, - from_dblock(b), &cmd->discard_root); + from_oblock(b), &cmd->discard_root); } -static int __is_discarded(struct dm_cache_metadata *cmd, dm_dblock_t b, +static int __is_discarded(struct dm_cache_metadata *cmd, dm_oblock_t b, bool *is_discarded) { return dm_bitset_test_bit(&cmd->discard_info, cmd->discard_root, - from_dblock(b), &cmd->discard_root, + from_oblock(b), &cmd->discard_root, is_discarded); } static int __discard(struct dm_cache_metadata *cmd, - dm_dblock_t dblock, bool discard) + dm_oblock_t dblock, bool discard) { int r; @@ -826,7 +826,7 @@ static int __discard(struct dm_cache_metadata *cmd, } int dm_cache_set_discard(struct dm_cache_metadata *cmd, - dm_dblock_t dblock, bool discard) + dm_oblock_t dblock, bool discard) { int r; @@ -844,8 +844,8 @@ static int __load_discards(struct dm_cache_metadata *cmd, dm_block_t b; bool discard; - for (b = 0; b < from_dblock(cmd->discard_nr_blocks); b++) { - dm_dblock_t dblock = to_dblock(b); + for (b = 0; b < from_oblock(cmd->discard_nr_blocks); b++) { + dm_oblock_t dblock = to_oblock(b); if (cmd->clean_when_opened) { r = __is_discarded(cmd, dblock, &discard); diff --git a/drivers/md/dm-cache-metadata.h b/drivers/md/dm-cache-metadata.h index cd906f14f98d..ce8468bb616e 100644 --- a/drivers/md/dm-cache-metadata.h +++ b/drivers/md/dm-cache-metadata.h @@ -72,14 +72,14 @@ dm_cblock_t dm_cache_size(struct dm_cache_metadata *cmd); int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, sector_t discard_block_size, - dm_dblock_t new_nr_entries); + dm_oblock_t new_nr_entries); typedef int (*load_discard_fn)(void *context, sector_t discard_block_size, - dm_dblock_t dblock, bool discarded); + dm_oblock_t dblock, bool discarded); int dm_cache_load_discards(struct dm_cache_metadata *cmd, load_discard_fn fn, void *context); -int dm_cache_set_discard(struct dm_cache_metadata *cmd, dm_dblock_t dblock, bool discard); +int dm_cache_set_discard(struct dm_cache_metadata *cmd, dm_oblock_t dblock, bool discard); int dm_cache_remove_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock); int dm_cache_insert_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock, dm_oblock_t oblock); diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index bccb7ae34e61..8534679918f4 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -237,9 +237,8 @@ struct cache { /* * origin_blocks entries, discarded if set. */ - dm_dblock_t discard_nr_blocks; + dm_oblock_t discard_nr_blocks; unsigned long *discard_bitset; - uint32_t discard_block_size; /* * Rather than reconstructing the table line for the status we just @@ -526,48 +525,33 @@ static dm_block_t block_div(dm_block_t b, uint32_t n) return b; } -static dm_dblock_t oblock_to_dblock(struct cache *cache, dm_oblock_t oblock) -{ - uint32_t discard_blocks = cache->discard_block_size; - dm_block_t b = from_oblock(oblock); - - if (!block_size_is_power_of_two(cache)) - discard_blocks = discard_blocks / cache->sectors_per_block; - else - discard_blocks >>= cache->sectors_per_block_shift; - - b = block_div(b, discard_blocks); - - return to_dblock(b); -} - -static void set_discard(struct cache *cache, dm_dblock_t b) +static void set_discard(struct cache *cache, dm_oblock_t b) { unsigned long flags; atomic_inc(&cache->stats.discard_count); spin_lock_irqsave(&cache->lock, flags); - set_bit(from_dblock(b), cache->discard_bitset); + set_bit(from_oblock(b), cache->discard_bitset); spin_unlock_irqrestore(&cache->lock, flags); } -static void clear_discard(struct cache *cache, dm_dblock_t b) +static void clear_discard(struct cache *cache, dm_oblock_t b) { unsigned long flags; spin_lock_irqsave(&cache->lock, flags); - clear_bit(from_dblock(b), cache->discard_bitset); + clear_bit(from_oblock(b), cache->discard_bitset); spin_unlock_irqrestore(&cache->lock, flags); } -static bool is_discarded(struct cache *cache, dm_dblock_t b) +static bool is_discarded(struct cache *cache, dm_oblock_t b) { int r; unsigned long flags; spin_lock_irqsave(&cache->lock, flags); - r = test_bit(from_dblock(b), cache->discard_bitset); + r = test_bit(from_oblock(b), cache->discard_bitset); spin_unlock_irqrestore(&cache->lock, flags); return r; @@ -579,8 +563,7 @@ static bool is_discarded_oblock(struct cache *cache, dm_oblock_t b) unsigned long flags; spin_lock_irqsave(&cache->lock, flags); - r = test_bit(from_dblock(oblock_to_dblock(cache, b)), - cache->discard_bitset); + r = test_bit(from_oblock(b), cache->discard_bitset); spin_unlock_irqrestore(&cache->lock, flags); return r; @@ -705,7 +688,7 @@ static void remap_to_origin_clear_discard(struct cache *cache, struct bio *bio, check_if_tick_bio_needed(cache, bio); remap_to_origin(cache, bio); if (bio_data_dir(bio) == WRITE) - clear_discard(cache, oblock_to_dblock(cache, oblock)); + clear_discard(cache, oblock); } static void remap_to_cache_dirty(struct cache *cache, struct bio *bio, @@ -715,7 +698,7 @@ static void remap_to_cache_dirty(struct cache *cache, struct bio *bio, remap_to_cache(cache, bio, cblock); if (bio_data_dir(bio) == WRITE) { set_dirty(cache, oblock, cblock); - clear_discard(cache, oblock_to_dblock(cache, oblock)); + clear_discard(cache, oblock); } } @@ -1288,14 +1271,14 @@ static void process_flush_bio(struct cache *cache, struct bio *bio) static void process_discard_bio(struct cache *cache, struct bio *bio) { dm_block_t start_block = dm_sector_div_up(bio->bi_iter.bi_sector, - cache->discard_block_size); + cache->sectors_per_block); dm_block_t end_block = bio_end_sector(bio); dm_block_t b; - end_block = block_div(end_block, cache->discard_block_size); + end_block = block_div(end_block, cache->sectors_per_block); for (b = start_block; b < end_block; b++) - set_discard(cache, to_dblock(b)); + set_discard(cache, to_oblock(b)); bio_endio(bio, 0); } @@ -2292,14 +2275,13 @@ static int cache_create(struct cache_args *ca, struct cache **result) } clear_bitset(cache->dirty_bitset, from_cblock(cache->cache_size)); - cache->discard_block_size = cache->sectors_per_block; - cache->discard_nr_blocks = oblock_to_dblock(cache, cache->origin_blocks); - cache->discard_bitset = alloc_bitset(from_dblock(cache->discard_nr_blocks)); + cache->discard_nr_blocks = cache->origin_blocks; + cache->discard_bitset = alloc_bitset(from_oblock(cache->discard_nr_blocks)); if (!cache->discard_bitset) { *error = "could not allocate discard bitset"; goto bad; } - clear_bitset(cache->discard_bitset, from_dblock(cache->discard_nr_blocks)); + clear_bitset(cache->discard_bitset, from_oblock(cache->discard_nr_blocks)); cache->copier = dm_kcopyd_client_create(&dm_kcopyd_throttle); if (IS_ERR(cache->copier)) { @@ -2583,16 +2565,16 @@ static int write_discard_bitset(struct cache *cache) { unsigned i, r; - r = dm_cache_discard_bitset_resize(cache->cmd, cache->discard_block_size, - cache->discard_nr_blocks); + r = dm_cache_discard_bitset_resize(cache->cmd, cache->sectors_per_block, + cache->origin_blocks); if (r) { DMERR("could not resize on-disk discard bitset"); 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))); + for (i = 0; i < from_oblock(cache->discard_nr_blocks); i++) { + r = dm_cache_set_discard(cache->cmd, to_oblock(i), + is_discarded(cache, to_oblock(i))); if (r) return r; } @@ -2689,16 +2671,14 @@ static int load_mapping(void *context, dm_oblock_t oblock, dm_cblock_t cblock, } static int load_discard(void *context, sector_t discard_block_size, - dm_dblock_t dblock, bool discard) + dm_oblock_t oblock, bool discard) { struct cache *cache = context; - /* FIXME: handle mis-matched block size */ - if (discard) - set_discard(cache, dblock); + set_discard(cache, oblock); else - clear_discard(cache, dblock); + clear_discard(cache, oblock); return 0; } @@ -3089,8 +3069,8 @@ static void set_discard_limits(struct cache *cache, struct queue_limits *limits) /* * FIXME: these limits may be incompatible with the cache device */ - limits->max_discard_sectors = cache->discard_block_size; - limits->discard_granularity = cache->discard_block_size << SECTOR_SHIFT; + limits->max_discard_sectors = cache->sectors_per_block; + limits->discard_granularity = cache->sectors_per_block << SECTOR_SHIFT; } static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits) -- 2.20.1