+ xfs-fail-dax-mount-if-reflink-is-enabled-on-a-partition.patch added to mm-unstable branch

+ xfs-fail-dax-mount-if-reflink-is-enabled-on-a-partition.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: xfs: fail dax mount if reflink is enabled on a partition
has been added to the -mm mm-unstable branch.  Its filename is
     xfs-fail-dax-mount-if-reflink-is-enabled-on-a-partition.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/xfs-fail-dax-mount-if-reflink-is-enabled-on-a-partition.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Subject: xfs: fail dax mount if reflink is enabled on a partition
Date: Thu, 9 Jun 2022 22:34:35 +0800

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.

Link: https://lkml.kernel.org/r/20220609143435.393724-1-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/xfs/xfs_super.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/fs/xfs/xfs_super.c~xfs-fail-dax-mount-if-reflink-is-enabled-on-a-partition
+++ a/fs/xfs/xfs_super.c
@@ -350,8 +350,10 @@ 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;
 	}
 
_

Patches currently in -mm which might be from ruansy.fnst@fujitsu.com are

xfs-fail-dax-mount-if-reflink-is-enabled-on-a-partition.patch