[PATCH] xfs: only bother with sync_filesystem during readonly remount

["Darrick J. Wong" <djwong@kernel.org>]

From: Darrick J. Wong <djwong@kernel.org>

In commit 02b9984d6408, we pushed a sync_filesystem() call from the VFS
into xfs_fs_remount.  The only time that we ever need to push dirty file
data or metadata to disk for a remount is if we're remounting the
filesystem read only, so this really could be moved to xfs_remount_ro.

Once we've moved the call site, actually check the return value from
sync_filesystem.

Fixes: 02b9984d6408 ("fs: push sync_filesystem() down to the file system's remount_fs()")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
 fs/xfs/xfs_super.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 4c0dee78b2f8..d84714e4e46a 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1753,6 +1753,11 @@ xfs_remount_ro(
 	};
 	int			error;
 
+	/* Flush all the dirty data to disk. */
+	error = sync_filesystem(mp->m_super);
+	if (error)
+		return error;
+
 	/*
 	 * Cancel background eofb scanning so it cannot race with the final
 	 * log force+buftarg wait and deadlock the remount.
@@ -1831,8 +1836,6 @@ xfs_fs_reconfigure(
 	if (error)
 		return error;
 
-	sync_filesystem(mp->m_super);
-
 	/* inode32 -> inode64 */
 	if (xfs_has_small_inums(mp) && !xfs_has_small_inums(new_mp)) {
 		mp->m_features &= ~XFS_FEAT_SMALL_INUMS;