From: Chengguang Xu <redacted>

Now overlayfs can only sync own dirty inodes during syncfs,
so remove unnecessary sync_filesystem() on upper file system.

Signed-off-by: Chengguang Xu <redacted>
---
 fs/overlayfs/super.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index ccffcd96491d..213b795a6a86 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c

@@ -292,18 +292,14 @@ static int ovl_sync_fs(struct super_block *sb, int wait)
        /*
         * Not called for sync(2) call or an emergency sync (SB_I_SKIP_SYNC).
         * All the super blocks will be iterated, including upper_sb.
-        *
-        * If this is a syncfs(2) call, then we do need to call
-        * sync_filesystem() on upper_sb, but enough if we do it when being
-        * called with wait == 1.
         */
-       if (!wait)
-               return 0;
-
        upper_sb = ovl_upper_mnt(ofs)->mnt_sb;
-
        down_read(&upper_sb->s_umount);
-       ret = sync_filesystem(upper_sb);
+       if (wait)
+               wait_sb_inodes(upper_sb);
+       if (upper_sb->s_op->sync_fs)
+               upper_sb->s_op->sync_fs(upper_sb, wait);
+       ret = ovl_sync_upper_blockdev(upper_sb, wait);