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/ext3/super.c b/fs/ext3/super.c
index 546b8d732bf2..e213a2613a56 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -2491,6 +2491,7 @@ static int ext3_remount (struct super_block * sb, int * flags, char * data)
 #endif
 
         /* Store the original options */
+        lock_super(sb);
         old_sb_flags = sb->s_flags;
         old_opts.s_mount_opt = sbi->s_mount_opt;
         old_opts.s_resuid = sbi->s_resuid;
@@ -2598,6 +2599,7 @@ static int ext3_remount (struct super_block * sb, int * flags, char * data)
                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
                         kfree(old_opts.s_qf_names[i]);
 #endif
+        unlock_super(sb);
         return 0;
 restore_opts:
         sb->s_flags = old_sb_flags;
@@ -2614,6 +2616,7 @@ restore_opts:
                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
         }
 #endif
+        unlock_super(sb);
         return err;
 }