xfs: ignore HW which cannot atomic write a single block

Currently only HW which can write at least 1x block is supported.

For supporting atomic writes > 1x block, a CoW-based method will also be
used and this will not be resticted to using HW which can write >= 1x
block.

However for deciding if HW-based atomic writes can be used, we need to
start adding checks for write length < HW min, which complicates the
code.  Indeed, a statx field similar to unit_max_opt should also be
added for this minimum, which is undesirable.

HW which can only write > 1x blocks would be uncommon and quite weird,
so let's just not support it.

Signed-off-by: "Darrick J. Wong" <[email protected]>
Signed-off-by: John Garry <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>

1 files changed, 1 insertions, 9 deletions

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index d3471a7418b9..d7e2b902ef5c 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -358,15 +358,7 @@ static inline bool xfs_inode_has_bigrtalloc(const struct xfs_inode *ip)
 
 static inline bool xfs_inode_can_hw_atomic_write(const struct xfs_inode *ip)
 {
-	struct xfs_mount	*mp = ip->i_mount;
-	struct xfs_buftarg	*target = xfs_inode_buftarg(ip);
-
-	if (mp->m_sb.sb_blocksize < target->bt_bdev_awu_min)
-		return false;
-	if (mp->m_sb.sb_blocksize > target->bt_bdev_awu_max)
-		return false;
-
-	return true;
+	return xfs_inode_buftarg(ip)->bt_bdev_awu_max > 0;
 }
 
 /*