Commit be691b5e authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David Sterba
Browse files

btrfs: split bios to the fs sector size boundary 



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: d5e4377d ("btrfs: split zone append bios in btrfs_submit_bio")
CC: stable@vger.kernel.org # 6.12
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 6c3864e0

fs/btrfs/bio.c

+8 −2
Original line number Diff line number Diff line
@@ -649,8 +649,14 @@ static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length) 
	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;

}