--- a/usr/src/grub/grub-0.97/stage2/zfs-include/zfs.h	Sun May 20 02:46:39 2012 -0500
+++ b/usr/src/grub/grub-0.97/stage2/zfs-include/zfs.h	Mon May 21 12:11:39 2012 -0700
@@ -16,8 +16,10 @@
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
+
 /*
  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef	_SYS_FS_ZFS_H
@@ -26,7 +28,14 @@
 /*
  * On-disk version number.
  */
-#define	SPA_VERSION			28ULL
+#define	SPA_VERSION_INITIAL		1ULL
+#define	SPA_VERSION_BEFORE_FEATURES	28ULL
+#define	SPA_VERSION			5000ULL
+#define	SPA_VERSION_FEATURES		5000ULL
+
+#define	SPA_VERSION_IS_SUPPORTED(v) \
+	(((v) >= SPA_VERSION_INITIAL && (v) <= SPA_VERSION_BEFORE_FEATURES) || \
+	((v) >= SPA_VERSION_FEATURES && (v) <= SPA_VERSION))
 
 /*
  * The following are configuration names used in the nvlist describing a pool's
@@ -66,6 +75,7 @@
 #define	ZPOOL_CONFIG_DDT_HISTOGRAM	"ddt_histogram"
 #define	ZPOOL_CONFIG_DDT_OBJ_STATS	"ddt_object_stats"
 #define	ZPOOL_CONFIG_DDT_STATS		"ddt_stats"
+#define	ZPOOL_CONFIG_FEATURES_FOR_READ	"features_for_read"
 /*
  * The persistent vdev state is stored as separate values rather than a single
  * 'vdev_state' entry.  This is because a device can be in multiple states, such