->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, 0 insertions, 2 deletions

diff --git a/fs/super.c b/fs/super.c
index a64f36208797..1905f4af01cc 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -420,10 +420,8 @@ restart:
                         spin_unlock(&sb_lock);
 
                         down_read(&sb->s_umount);
-                        lock_super(sb);
                         if (sb->s_root && sb->s_dirt)
                                 sb->s_op->write_super(sb);
-                        unlock_super(sb);
                         up_read(&sb->s_umount);
 
                         spin_lock(&sb_lock);