6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Christoph Hellwig <hch@xxxxxx>
commit be691b5e593f2cc8cef67bbc59c1fb91b74a86a9 upstream.
Btrfs like other file systems can't really deal with I/O not aligned to
it's internal block size (which strangely is called sector size in
btrfs, for historical reasons), but the block layer split helper doesn't
even know about that.
Round down the split boundary so that all I/Os are aligned.
Fixes: d5e4377d5051 ("btrfs: split zone append bios in btrfs_submit_bio")
CC: stable@xxxxxxxxxxxxxxx # 6.12
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/bio.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -649,8 +649,14 @@ static u64 btrfs_append_map_length(struc
map_length = min(map_length, bbio->fs_info->max_zone_append_size);
sector_offset = bio_split_rw_at(&bbio->bio, &bbio->fs_info->limits,
&nr_segs, map_length);
- if (sector_offset)
- return sector_offset << SECTOR_SHIFT;
+ if (sector_offset) {
+ /*
+ * bio_split_rw_at() could split at a size smaller than our
+ * sectorsize and thus cause unaligned I/Os. Fix that by
+ * always rounding down to the nearest boundary.
+ */
+ return ALIGN_DOWN(sector_offset << SECTOR_SHIFT, bbio->fs_info->sectorsize);
+ }
return map_length;
}
