Merge tag 'omapdrm-fixes-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba...

[karo-tx-linux.git] / drivers / md / dm-cache-metadata.c

diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index 9ef0752e8a08c4edb0ba422738da707270f60831..4ead4ba606562b0c33d750064660a4effe0594ea 100644 (file)
--- 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;
@@ -120,6 +120,12 @@ struct dm_cache_metadata {
        unsigned policy_version[CACHE_POLICY_VERSION_SIZE];
        size_t policy_hint_size;
        struct dm_cache_statistics stats;
+
+       /*
+        * Reading the space map root can fail, so we read it into this
+        * buffer before the superblock is locked and updated.
+        */
+       __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
 };
 
 /*-------------------------------------------------------------------
@@ -260,11 +266,31 @@ static void __setup_mapping_info(struct dm_cache_metadata *cmd)
        }
 }
 
+static int __save_sm_root(struct dm_cache_metadata *cmd)
+{
+       int r;
+       size_t metadata_len;
+
+       r = dm_sm_root_size(cmd->metadata_sm, &metadata_len);
+       if (r < 0)
+               return r;
+
+       return dm_sm_copy_root(cmd->metadata_sm, &cmd->metadata_space_map_root,
+                              metadata_len);
+}
+
+static void __copy_sm_root(struct dm_cache_metadata *cmd,
+                          struct cache_disk_superblock *disk_super)
+{
+       memcpy(&disk_super->metadata_space_map_root,
+              &cmd->metadata_space_map_root,
+              sizeof(cmd->metadata_space_map_root));
+}
+
 static int __write_initial_superblock(struct dm_cache_metadata *cmd)
 {
        int r;
        struct dm_block *sblock;
-       size_t metadata_len;
        struct cache_disk_superblock *disk_super;
        sector_t bdev_size = i_size_read(cmd->bdev->bd_inode) >> SECTOR_SHIFT;
 
@@ -272,12 +298,16 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd)
        if (bdev_size > DM_CACHE_METADATA_MAX_SECTORS)
                bdev_size = DM_CACHE_METADATA_MAX_SECTORS;
 
-       r = dm_sm_root_size(cmd->metadata_sm, &metadata_len);
+       r = dm_tm_pre_commit(cmd->tm);
        if (r < 0)
                return r;
 
-       r = dm_tm_pre_commit(cmd->tm);
-       if (r < 0)
+       /*
+        * dm_sm_copy_root() can fail.  So we need to do it before we start
+        * updating the superblock.
+        */
+       r = __save_sm_root(cmd);
+       if (r)
                return r;
 
        r = superblock_lock_zero(cmd, &sblock);
@@ -293,16 +323,13 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd)
        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,
-                           metadata_len);
-       if (r < 0)
-               goto bad_locked;
+       __copy_sm_root(cmd, disk_super);
 
        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);
        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);
@@ -313,10 +340,6 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd)
        disk_super->write_misses = cpu_to_le32(0);
 
        return dm_tm_commit(cmd->tm, sblock);
-
-bad_locked:
-       dm_bm_unlock(sblock);
-       return r;
 }
 
 static int __format_metadata(struct dm_cache_metadata *cmd)
@@ -496,7 +519,7 @@ 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));
@@ -530,8 +553,9 @@ static int __begin_transaction_flags(struct dm_cache_metadata *cmd,
        disk_super = dm_block_data(sblock);
        update_flags(disk_super, mutator);
        read_superblock_fields(cmd, disk_super);
+       dm_bm_unlock(sblock);
 
-       return dm_bm_flush_and_unlock(cmd->bm, sblock);
+       return dm_bm_flush(cmd->bm);
 }
 
 static int __begin_transaction(struct dm_cache_metadata *cmd)
@@ -559,7 +583,6 @@ static int __commit_transaction(struct dm_cache_metadata *cmd,
                                flags_mutator mutator)
 {
        int r;
-       size_t metadata_len;
        struct cache_disk_superblock *disk_super;
        struct dm_block *sblock;
 
@@ -577,8 +600,8 @@ static int __commit_transaction(struct dm_cache_metadata *cmd,
        if (r < 0)
                return r;
 
-       r = dm_sm_root_size(cmd->metadata_sm, &metadata_len);
-       if (r < 0)
+       r = __save_sm_root(cmd);
+       if (r)
                return r;
 
        r = superblock_lock(cmd, &sblock);
@@ -594,7 +617,7 @@ 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]);
@@ -605,13 +628,7 @@ static int __commit_transaction(struct dm_cache_metadata *cmd,
        disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses);
        disk_super->write_hits = cpu_to_le32(cmd->stats.write_hits);
        disk_super->write_misses = cpu_to_le32(cmd->stats.write_misses);
-
-       r = dm_sm_copy_root(cmd->metadata_sm, &disk_super->metadata_space_map_root,
-                           metadata_len);
-       if (r < 0) {
-               dm_bm_unlock(sblock);
-               return r;
-       }
+       __copy_sm_root(cmd, disk_super);
 
        return dm_tm_commit(cmd->tm, sblock);
 }
@@ -771,15 +788,15 @@ 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 +809,28 @@ 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 +843,7 @@ 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 +861,8 @@ 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);
@@ -1228,22 +1245,12 @@ static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *po
        return 0;
 }
 
-int dm_cache_begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
+static int save_hint(void *context, dm_cblock_t cblock, dm_oblock_t oblock, uint32_t hint)
 {
+       struct dm_cache_metadata *cmd = context;
+       __le32 value = cpu_to_le32(hint);
        int r;
 
-       down_write(&cmd->root_lock);
-       r = begin_hints(cmd, policy);
-       up_write(&cmd->root_lock);
-
-       return r;
-}
-
-static int save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock,
-                    uint32_t hint)
-{
-       int r;
-       __le32 value = cpu_to_le32(hint);
        __dm_bless_for_disk(&value);
 
        r = dm_array_set_value(&cmd->hint_info, cmd->hint_root,
@@ -1253,16 +1260,25 @@ static int save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock,
        return r;
 }
 
-int dm_cache_save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock,
-                      uint32_t hint)
+static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
 {
        int r;
 
-       if (!hints_array_initialized(cmd))
-               return 0;
+       r = begin_hints(cmd, policy);
+       if (r) {
+               DMERR("begin_hints failed");
+               return r;
+       }
+
+       return policy_walk_mappings(policy, save_hint, cmd);
+}
+
+int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
+{
+       int r;
 
        down_write(&cmd->root_lock);
-       r = save_hint(cmd, cblock, hint);
+       r = write_hints(cmd, policy);
        up_write(&cmd->root_lock);
 
        return r;