Btrfs: Back port to 2.6.18-el kernels

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 7213012..ebb2db6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -593,8 +593,11 @@
 	fs_info->do_barriers = 1;
 	fs_info->closing = 0;
 	fs_info->total_pinned = 0;
-
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
+	INIT_WORK(&fs_info->trans_work, btrfs_transaction_cleaner, fs_info);
+#else
 	INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
+#endif
 	BTRFS_I(fs_info->btree_inode)->root = tree_root;
 	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
 	       sizeof(struct btrfs_key));