->write_super lock_super pushdown

Push down lock_super into ->write_super instances and remove it from the
caller.

Following filesystem don't need ->s_lock in ->write_super and are skipped:

 * bfs, nilfs2 - no other uses of s_lock and have internal locks in
	->write_super
 * ext2 - uses BKL in ext2_write_super and has internal calls without s_lock
 * reiserfs - no other uses of s_lock as has reiserfs_write_lock (BKL) in
 	->write_super
 * xfs - no other uses of s_lock and uses internal lock (buffer lock on
	superblock buffer) to serialize ->write_super.  Also xfs_fs_write_super
	is superflous and will go away in the next merge window

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c
index e0a39f1fb88e..a3f45fc626a1 100644
--- a/fs/sysv/inode.c
+++ b/fs/sysv/inode.c
@@ -37,6 +37,7 @@ static void sysv_write_super(struct super_block *sb)
         struct sysv_sb_info *sbi = SYSV_SB(sb);
         unsigned long time = get_seconds(), old_time;
 
+        lock_super(sb);
         lock_kernel();
         if (sb->s_flags & MS_RDONLY)
                 goto clean;
@@ -56,6 +57,7 @@ static void sysv_write_super(struct super_block *sb)
 clean:
         sb->s_dirt = 0;
         unlock_kernel();
+        unlock_super(sb);
 }
 
 static int sysv_remount(struct super_block *sb, int *flags, char *data)