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, 3 insertions, 0 deletions

diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c
index 437a32e9dea..f68193cf081 100644
--- a/fs/hpfs/super.c
+++ b/fs/hpfs/super.c
@@ -398,6 +398,7 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
         
         *flags |= MS_NOATIME;
         
+        lock_super(s);
         uid = sbi->sb_uid; gid = sbi->sb_gid;
         umask = 0777 & ~sbi->sb_mode;
         lowercase = sbi->sb_lowercase; conv = sbi->sb_conv;
@@ -430,9 +431,11 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
 
         replace_mount_options(s, new_opts);
 
+        unlock_super(s);
         return 0;
 
 out_err:
+        unlock_super(s);
         kfree(new_opts);
         return -EINVAL;
 }