hfs: add ->sync_fs

Add a ->sync_fs method for data integrity syncs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

fs/hfs/super.c

@@ -58,6 +58,16 @@ static void hfs_write_super(struct super_block *sb)
 	unlock_super(sb);
 }
 
+static int hfs_sync_fs(struct super_block *sb, int wait)
+{
+	lock_super(sb);
+	hfs_mdb_commit(sb);
+	sb->s_dirt = 0;
+	unlock_super(sb);
+
+	return 0;
+}
+
 /*
  * hfs_put_super()
  *
@@ -172,6 +182,7 @@ static const struct super_operations hfs_super_operations = {
 	.clear_inode	= hfs_clear_inode,
 	.put_super	= hfs_put_super,
 	.write_super	= hfs_write_super,
+	.sync_fs	= hfs_sync_fs,
 	.statfs		= hfs_statfs,
 	.remount_fs     = hfs_remount,
 	.show_options	= hfs_show_options,