--- a/usr/src/uts/common/fs/zfs/sys/dsl_scan.h	Sun May 20 02:46:39 2012 -0500
+++ b/usr/src/uts/common/fs/zfs/sys/dsl_scan.h	Mon May 21 12:11:39 2012 -0700
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef	_SYS_DSL_SCAN_H
@@ -79,6 +80,9 @@
 	uint64_t scn_sync_start_time;
 	zio_t *scn_zio_root;
 
+	/* for freeing blocks */
+	boolean_t scn_is_bptree;
+
 	/* for debugging / information */
 	uint64_t scn_visited_this_txg;