->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, 5 insertions, 1 deletions

diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 9b292dcc39c8..1aab8aa7801e 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -157,10 +157,12 @@ static void hfsplus_write_super(struct super_block *sb)
         struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;
 
         dprint(DBG_SUPER, "hfsplus_write_super\n");
+
+        lock_super(sb);
         sb->s_dirt = 0;
         if (sb->s_flags & MS_RDONLY)
                 /* warn? */
-                return;
+                goto out;
 
         vhdr->free_blocks = cpu_to_be32(HFSPLUS_SB(sb).free_blocks);
         vhdr->next_alloc = cpu_to_be32(HFSPLUS_SB(sb).next_alloc);
@@ -192,6 +194,8 @@ static void hfsplus_write_super(struct super_block *sb)
                 }
                 HFSPLUS_SB(sb).flags &= ~HFSPLUS_SB_WRITEBACKUP;
         }
+ out:
+        unlock_super(sb);
 }
 
 static void hfsplus_put_super(struct super_block *sb)