xfs: get allocation alignment from the buftarg

Needed to feed into the allocation routine to guarantee the memory
buffers we add to bios are correctly aligned to the underlying
device.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index c6e57a3f409ee7855474bb323d5037a6f96ab97b..f6ce17d8d8480f2836c5440d35313facb5802ac9 100644 (file)
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -350,6 +350,12 @@ extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int);
 #define xfs_getsize_buftarg(buftarg)   block_size((buftarg)->bt_bdev)
 #define xfs_readonly_buftarg(buftarg)  bdev_read_only((buftarg)->bt_bdev)
 
+static inline int
+xfs_buftarg_dma_alignment(struct xfs_buftarg *bt)
+{
+       return queue_dma_alignment(bt->bt_bdev->bd_disk->queue);
+}
+
 int xfs_buf_reverify(struct xfs_buf *bp, const struct xfs_buf_ops *ops);
 bool xfs_verify_magic(struct xfs_buf *bp, __be32 dmagic);
 bool xfs_verify_magic16(struct xfs_buf *bp, __be16 dmagic);