Btrfs: Maintain a list of inodes that are delalloc and a way to wait on them

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index df624fd..534ac41 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -42,6 +42,8 @@
 	/* for keeping track of orphaned inodes */
 	struct list_head i_orphan;
 
+	struct list_head delalloc_inodes;
+
 	/*
 	 * transid of the trans_handle that last modified this inode
 	 */