diff options
Diffstat (limited to 'drivers/md/dm-thin-metadata.c')
| -rw-r--r-- | drivers/md/dm-thin-metadata.c | 175 |
1 files changed, 139 insertions, 36 deletions
diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index 60bce435f4f..e9d33ad59df 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -76,7 +76,7 @@ #define THIN_SUPERBLOCK_MAGIC 27022010 #define THIN_SUPERBLOCK_LOCATION 0 -#define THIN_VERSION 1 +#define THIN_VERSION 2 #define THIN_METADATA_CACHE_SIZE 64 #define SECTOR_TO_BLOCK_SHIFT 3 @@ -192,6 +192,13 @@ struct dm_pool_metadata { * operation possible in this state is the closing of the device. */ bool fail_io:1; + + /* + * Reading the space map roots can fail, so we read it into these + * buffers before the superblock is locked and updated. + */ + __u8 data_space_map_root[SPACE_MAP_ROOT_SIZE]; + __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE]; }; struct dm_thin_device { @@ -431,26 +438,53 @@ static void __setup_btree_details(struct dm_pool_metadata *pmd) pmd->details_info.value_type.equal = NULL; } +static int save_sm_roots(struct dm_pool_metadata *pmd) +{ + int r; + size_t len; + + r = dm_sm_root_size(pmd->metadata_sm, &len); + if (r < 0) + return r; + + r = dm_sm_copy_root(pmd->metadata_sm, &pmd->metadata_space_map_root, len); + if (r < 0) + return r; + + r = dm_sm_root_size(pmd->data_sm, &len); + if (r < 0) + return r; + + return dm_sm_copy_root(pmd->data_sm, &pmd->data_space_map_root, len); +} + +static void copy_sm_roots(struct dm_pool_metadata *pmd, + struct thin_disk_superblock *disk) +{ + memcpy(&disk->metadata_space_map_root, + &pmd->metadata_space_map_root, + sizeof(pmd->metadata_space_map_root)); + + memcpy(&disk->data_space_map_root, + &pmd->data_space_map_root, + sizeof(pmd->data_space_map_root)); +} + static int __write_initial_superblock(struct dm_pool_metadata *pmd) { int r; struct dm_block *sblock; - size_t metadata_len, data_len; struct thin_disk_superblock *disk_super; sector_t bdev_size = i_size_read(pmd->bdev->bd_inode) >> SECTOR_SHIFT; if (bdev_size > THIN_METADATA_MAX_SECTORS) bdev_size = THIN_METADATA_MAX_SECTORS; - r = dm_sm_root_size(pmd->metadata_sm, &metadata_len); - if (r < 0) - return r; - - r = dm_sm_root_size(pmd->data_sm, &data_len); + r = dm_sm_commit(pmd->data_sm); if (r < 0) return r; - r = dm_sm_commit(pmd->data_sm); + r = save_sm_roots(pmd); if (r < 0) return r; @@ -471,27 +505,15 @@ static int __write_initial_superblock(struct dm_pool_metadata *pmd) disk_super->trans_id = 0; disk_super->held_root = 0; - r = dm_sm_copy_root(pmd->metadata_sm, &disk_super->metadata_space_map_root, - metadata_len); - if (r < 0) - goto bad_locked; - - r = dm_sm_copy_root(pmd->data_sm, &disk_super->data_space_map_root, - data_len); - if (r < 0) - goto bad_locked; + copy_sm_roots(pmd, disk_super); disk_super->data_mapping_root = cpu_to_le64(pmd->root); disk_super->device_details_root = cpu_to_le64(pmd->details_root); - disk_super->metadata_block_size = cpu_to_le32(THIN_METADATA_BLOCK_SIZE >> SECTOR_SHIFT); + disk_super->metadata_block_size = cpu_to_le32(THIN_METADATA_BLOCK_SIZE); disk_super->metadata_nr_blocks = cpu_to_le64(bdev_size >> SECTOR_TO_BLOCK_SHIFT); disk_super->data_block_size = cpu_to_le32(pmd->data_block_size); return dm_tm_commit(pmd->tm, sblock); - -bad_locked: - dm_bm_unlock(sblock); - return r; } static int __format_metadata(struct dm_pool_metadata *pmd) @@ -591,6 +613,15 @@ static int __open_metadata(struct dm_pool_metadata *pmd) disk_super = dm_block_data(sblock); + /* Verify the data block size hasn't changed */ + if (le32_to_cpu(disk_super->data_block_size) != pmd->data_block_size) { + DMERR("changing the data block size (from %u to %llu) is not supported", + le32_to_cpu(disk_super->data_block_size), + (unsigned long long)pmd->data_block_size); + r = -EINVAL; + goto bad_unlock_sblock; + } + r = __check_incompat_features(disk_super, pmd); if (r < 0) goto bad_unlock_sblock; @@ -651,7 +682,7 @@ static int __create_persistent_data_objects(struct dm_pool_metadata *pmd, bool f { int r; - pmd->bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE, + pmd->bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE << SECTOR_SHIFT, THIN_METADATA_CACHE_SIZE, THIN_MAX_CONCURRENT_LOCKS); if (IS_ERR(pmd->bm)) { @@ -769,6 +800,10 @@ static int __commit_transaction(struct dm_pool_metadata *pmd) if (r < 0) return r; + r = save_sm_roots(pmd); + if (r < 0) + return r; + r = superblock_lock(pmd, &sblock); if (r) return r; @@ -780,21 +815,9 @@ static int __commit_transaction(struct dm_pool_metadata *pmd) disk_super->trans_id = cpu_to_le64(pmd->trans_id); disk_super->flags = cpu_to_le32(pmd->flags); - r = dm_sm_copy_root(pmd->metadata_sm, &disk_super->metadata_space_map_root, - metadata_len); - if (r < 0) - goto out_locked; - - r = dm_sm_copy_root(pmd->data_sm, &disk_super->data_space_map_root, - data_len); - if (r < 0) - goto out_locked; + copy_sm_roots(pmd, disk_super); return dm_tm_commit(pmd->tm, sblock); - -out_locked: - dm_bm_unlock(sblock); - return r; } struct dm_pool_metadata *dm_pool_metadata_open(struct block_device *bdev, @@ -1349,6 +1372,12 @@ dm_thin_id dm_thin_dev_id(struct dm_thin_device *td) return td->id; } +/* + * Check whether @time (of block creation) is older than @td's last snapshot. + * If so then the associated block is shared with the last snapshot device. + * Any block on a device created *after* the device last got snapshotted is + * necessarily not shared. + */ static bool __snapshotted_since(struct dm_thin_device *td, uint32_t time) { return td->snapshotted_time > time; @@ -1458,6 +1487,20 @@ int dm_thin_remove_block(struct dm_thin_device *td, dm_block_t block) return r; } +int dm_pool_block_is_used(struct dm_pool_metadata *pmd, dm_block_t b, bool *result) +{ + int r; + uint32_t ref_count; + + down_read(&pmd->root_lock); + r = dm_sm_get_count(pmd->data_sm, b, &ref_count); + if (!r) + *result = (ref_count != 0); + up_read(&pmd->root_lock); + + return r; +} + bool dm_thin_changed_this_transaction(struct dm_thin_device *td) { int r; @@ -1469,6 +1512,23 @@ bool dm_thin_changed_this_transaction(struct dm_thin_device *td) return r; } +bool dm_pool_changed_this_transaction(struct dm_pool_metadata *pmd) +{ + bool r = false; + struct dm_thin_device *td, *tmp; + + down_read(&pmd->root_lock); + list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) { + if (td->changed) { + r = td->changed; + break; + } + } + up_read(&pmd->root_lock); + + return r; +} + bool dm_thin_aborted_changes(struct dm_thin_device *td) { bool r; @@ -1697,6 +1757,14 @@ void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd) up_write(&pmd->root_lock); } +void dm_pool_metadata_read_write(struct dm_pool_metadata *pmd) +{ + down_write(&pmd->root_lock); + pmd->read_only = false; + dm_bm_set_read_write(pmd->bm); + up_write(&pmd->root_lock); +} + int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd, dm_block_t threshold, dm_sm_threshold_fn fn, @@ -1710,3 +1778,38 @@ int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd, return r; } + +int dm_pool_metadata_set_needs_check(struct dm_pool_metadata *pmd) +{ + int r; + struct dm_block *sblock; + struct thin_disk_superblock *disk_super; + + down_write(&pmd->root_lock); + pmd->flags |= THIN_METADATA_NEEDS_CHECK_FLAG; + + r = superblock_lock(pmd, &sblock); + if (r) { + DMERR("couldn't read superblock"); + goto out; + } + + disk_super = dm_block_data(sblock); + disk_super->flags = cpu_to_le32(pmd->flags); + + dm_bm_unlock(sblock); +out: + up_write(&pmd->root_lock); + return r; +} + +bool dm_pool_metadata_needs_check(struct dm_pool_metadata *pmd) +{ + bool needs_check; + + down_read(&pmd->root_lock); + needs_check = pmd->flags & THIN_METADATA_NEEDS_CHECK_FLAG; + up_read(&pmd->root_lock); + + return needs_check; +} |