diff options
author | Naohiro Aota <naohiro.aota@wdc.com> | 2021-02-04 19:21:52 +0900 |
---|---|---|
committer | David Sterba <dsterba@suse.com> | 2021-02-09 02:46:03 +0100 |
commit | 169e0da91a21a571093feb8ff84c7e9229e64c08 (patch) | |
tree | 22c27a901122d21acc03d47b53b55b84946e8fd4 /fs/btrfs/zoned.h | |
parent | a94794d50d788d4735fd8f656ac8c0510117457d (diff) | |
download | linux-169e0da91a21a571093feb8ff84c7e9229e64c08.tar.bz2 |
btrfs: zoned: track unusable bytes for zones
In a zoned filesystem a once written then freed region is not usable
until the underlying zone has been reset. So we need to distinguish such
unusable space from usable free space.
Therefore we need to introduce the "zone_unusable" field to the block
group structure, and "bytes_zone_unusable" to the space_info structure
to track the unusable space.
Pinned bytes are always reclaimed to the unusable space. But, when an
allocated region is returned before using e.g., the block group becomes
read-only between allocation time and reservation time, we can safely
return the region to the block group. For the situation, this commit
introduces "btrfs_add_free_space_unused". This behaves the same as
btrfs_add_free_space() on regular filesystem. On zoned filesystems, it
rewinds the allocation offset.
Because the read-only bytes tracks free but unusable bytes when the block
group is read-only, we need to migrate the zone_unusable bytes to
read-only bytes when a block group is marked read-only.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/zoned.h')
-rw-r--r-- | fs/btrfs/zoned.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h index d27db3993e51..37304d1675e6 100644 --- a/fs/btrfs/zoned.h +++ b/fs/btrfs/zoned.h @@ -42,6 +42,7 @@ int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical, u64 length, u64 *bytes); int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size); int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new); +void btrfs_calc_zone_unusable(struct btrfs_block_group *cache); #else /* CONFIG_BLK_DEV_ZONED */ static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos, struct blk_zone *zone) @@ -123,6 +124,8 @@ static inline int btrfs_load_block_group_zone_info( return 0; } +static inline void btrfs_calc_zone_unusable(struct btrfs_block_group *cache) { } + #endif static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos) |