Push lock_super() into the ->remount_fs() of filesystems that care about it

Note that since we can't run into contention between remount_fs and write_super
(due to exclusion on s_umount), we have to care only about filesystems that
touch lock_super() on their own.  Out of those ext3, ext4, hpfs, sysv and ufs
do need it; fat doesn't since its ->remount_fs() only accesses assign-once
data (basically, it's "we have no atime on directories and only have atime on
files for vfat; force nodiratime and possibly noatime into *flags").

[folded a build fix from hch]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 0 insertions, 2 deletions

diff --git a/fs/super.c b/fs/super.c
index bdd7158b785e..2a49fed77453 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -556,9 +556,7 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
         remount_rw = !(flags & MS_RDONLY) && (sb->s_flags & MS_RDONLY);
 
         if (sb->s_op->remount_fs) {
-                lock_super(sb);
                 retval = sb->s_op->remount_fs(sb, &flags, data);
-                unlock_super(sb);
                 if (retval)
                         return retval;
         }