[PATCH] xfs: fail dax mount if reflink is enabled on a partition

[Shiyang Ruan]

Failure notification is not supported on partitions.  So, when we mount
a reflink enabled xfs on a partition with dax option, let it fail with
-EINVAL code.

Signed-off-by: Shiyang Ruan <ruansy.f...@fujitsu.com>
---
 fs/xfs/xfs_super.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 8495ef076ffc..a3c221841fa6 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -348,8 +348,10 @@ xfs_setup_dax_always(
                goto disable_dax;
        }
 
-       if (xfs_has_reflink(mp)) {
-               xfs_alert(mp, "DAX and reflink cannot be used together!");
+       if (xfs_has_reflink(mp) &&
+           bdev_is_partition(mp->m_ddev_targp->bt_bdev)) {
+               xfs_alert(mp,
+                       "DAX and reflink cannot work with multi-partitions!");
                return -EINVAL;
        }
 
-- 
2.36.1