diff options
| author | Qu Wenruo <wqu@suse.com> | 2023-02-17 08:36:58 +0300 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2023-04-17 19:01:14 +0300 |
| commit | a97699d1d610710fb0103addaac3b590716f2de4 (patch) | |
| tree | b47acb103e385484e2f08ba3bf9400d74fccf598 /fs/btrfs/block-group.c | |
| parent | dcb2137c8411d9940ebdfc93bb4de20b7f8fcf42 (diff) | |
| download | linux-a97699d1d610710fb0103addaac3b590716f2de4.tar.xz | |
btrfs: replace map_lookup->stripe_len by BTRFS_STRIPE_LEN
Currently btrfs doesn't support stripe lengths other than 64KiB.
This is already set in the tree-checker.
There is really no meaning to record that fixed value in map_lookup for
now, and can all be replaced with BTRFS_STRIPE_LEN.
Furthermore we can use the fix stripe length to do the following
optimization:
- Use BTRFS_STRIPE_LEN_SHIFT to replace some 64bit division
Now we only need to do a right shift.
And the value of BTRFS_STRIPE_LEN itself is already too large for bit
shift, thus if we accidentally use BTRFS_STRIPE_LEN to do bit shift,
a compiler warning would be triggered.
Thus this bit shift optimization would be safe.
- Use BTRFS_STRIPE_LEN_MASK to calculate the offset inside a stripe
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/block-group.c')
| -rw-r--r-- | fs/btrfs/block-group.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 5fc670c27f86..b27474731e7b 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1977,12 +1977,12 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, map = em->map_lookup; data_stripe_length = em->orig_block_len; - io_stripe_size = map->stripe_len; + io_stripe_size = BTRFS_STRIPE_LEN; chunk_start = em->start; /* For RAID5/6 adjust to a full IO stripe length */ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) - io_stripe_size = map->stripe_len * nr_data_stripes(map); + io_stripe_size = nr_data_stripes(map) << BTRFS_STRIPE_LEN_SHIFT; buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS); if (!buf) { @@ -2000,8 +2000,10 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, data_stripe_length)) continue; - stripe_nr = physical - map->stripes[i].physical; - stripe_nr = div64_u64_rem(stripe_nr, map->stripe_len, &offset); + stripe_nr = (physical - map->stripes[i].physical) >> + BTRFS_STRIPE_LEN_SHIFT; + offset = (physical - map->stripes[i].physical) & + BTRFS_STRIPE_LEN_MASK; if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { |