diff options
| author | David Woodhouse <David.Woodhouse@intel.com> | 2013-01-29 18:40:14 -0500 |
|---|---|---|
| committer | Chris Mason <chris.mason@fusionio.com> | 2013-02-01 14:24:23 -0500 |
| commit | 53b381b3abeb86f12787a6c40fee9b2f71edc23b (patch) | |
| tree | c1018ba2157778f0200d2ede0c0df48fe5df8f14 /fs/btrfs/volumes.h | |
| parent | 64a167011bcabc1e855658387c8a4464b71f3138 (diff) | |
| download | linux-53b381b3abeb86f12787a6c40fee9b2f71edc23b.tar.bz2 | |
Btrfs: RAID5 and RAID6
This builds on David Woodhouse's original Btrfs raid5/6 implementation.
The code has changed quite a bit, blame Chris Mason for any bugs.
Read/modify/write is done after the higher levels of the filesystem have
prepared a given bio. This means the higher layers are not responsible
for building full stripes, and they don't need to query for the topology
of the extents that may get allocated during delayed allocation runs.
It also means different files can easily share the same stripe.
But, it does expose us to incorrect parity if we crash or lose power
while doing a read/modify/write cycle. This will be addressed in a
later commit.
Scrub is unable to repair crc errors on raid5/6 chunks.
Discard does not work on raid5/6 (yet)
The stripe size is fixed at 64KiB per disk. This will be tunable
in a later commit.
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Diffstat (limited to 'fs/btrfs/volumes.h')
| -rw-r--r-- | fs/btrfs/volumes.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index d3c3939ac751..0c2b856ecd98 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -321,7 +321,14 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, struct btrfs_device *tgtdev); int btrfs_scratch_superblock(struct btrfs_device *device); - +void btrfs_schedule_bio(struct btrfs_root *root, + struct btrfs_device *device, + int rw, struct bio *bio); +int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree, + u64 logical, u64 len, int mirror_num); +unsigned long btrfs_full_stripe_len(struct btrfs_root *root, + struct btrfs_mapping_tree *map_tree, + u64 logical); static inline void btrfs_dev_stat_inc(struct btrfs_device *dev, int index) { |