Illumos #2619 and #2747

2619 asynchronous destruction of ZFS file systems
2747 SPA versioning with zfs feature flags
Reviewed by: Matt Ahrens <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: Richard Lowe <[email protected]>
Reviewed by: Dan Kruchinin <[email protected]>
Approved by: Eric Schrock <[email protected]>

References:
  illumos/illumos-gate@53089ab7c84db6fb76c16ca50076c147cda11757
  illumos/illumos-gate@ad135b5d644628e791c3188a6ecbd9c257961ef8
  illumos changeset: 13700:2889e2596bd6
  https://www.illumos.org/issues/2619
  https://www.illumos.org/issues/2747

NOTE: The grub specific changes were not ported.  This change
must be made to the Linux grub packages.

Ported-by: Brian Behlendorf <[email protected]>

19 files changed, 449 insertions, 26 deletions

diff --git a/include/Makefile.am b/include/Makefile.am
index 8f9c8d729..8325a8ec0 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -1,6 +1,7 @@
 SUBDIRS = linux sys
 
 COMMON_H = \
+	$(top_srcdir)/include/zfeature_common.h \
 	$(top_srcdir)/include/zfs_comutil.h \
 	$(top_srcdir)/include/zfs_deleg.h \
 	$(top_srcdir)/include/zfs_fletcher.h \
diff --git a/include/libzfs.h b/include/libzfs.h
index e59350c9d..83ac34394 100644
--- a/include/libzfs.h
+++ b/include/libzfs.h
@@ -301,6 +301,15 @@ typedef enum {
 	ZPOOL_STATUS_BAD_LOG,		/* cannot read log chain(s) */
 
 	/*
+	 * If the pool has unsupported features but can still be opened in
+	 * read-only mode, its status is ZPOOL_STATUS_UNSUP_FEAT_WRITE. If the
+	 * pool has unsupported features but cannot be opened at all, its
+	 * status is ZPOOL_STATUS_UNSUP_FEAT_READ.
+	 */
+	ZPOOL_STATUS_UNSUP_FEAT_READ,	/* unsupported features for read */
+	ZPOOL_STATUS_UNSUP_FEAT_WRITE,	/* unsupported features for write */
+
+	/*
 	 * These faults have no corresponding message ID.  At the time we are
 	 * checking the status, the original reason for the FMA fault (I/O or
 	 * checksum errors) has been lost.
@@ -332,6 +341,7 @@ extern void zpool_dump_ddt(const ddt_stat_t *dds, const ddt_histogram_t *ddh);
  * Statistics and configuration functions.
  */
 extern nvlist_t *zpool_get_config(zpool_handle_t *, nvlist_t **);
+extern nvlist_t *zpool_get_features(zpool_handle_t *);
 extern int zpool_refresh_stats(zpool_handle_t *, boolean_t *);
 extern int zpool_get_errlog(zpool_handle_t *, nvlist_t **);
 
@@ -344,6 +354,7 @@ extern int zpool_import(libzfs_handle_t *, nvlist_t *, const char *,
     char *altroot);
 extern int zpool_import_props(libzfs_handle_t *, nvlist_t *, const char *,
     nvlist_t *, int);
+extern void zpool_print_unsup_feat(nvlist_t *config);
 
 /*
  * Search for pools to import
@@ -435,6 +446,8 @@ extern int zfs_prop_get_written_int(zfs_handle_t *zhp, const char *propname,
     uint64_t *propvalue);
 extern int zfs_prop_get_written(zfs_handle_t *zhp, const char *propname,
     char *propbuf, int proplen, boolean_t literal);
+extern int zfs_prop_get_feature(zfs_handle_t *zhp, const char *propname,
+    char *buf, size_t len);
 extern int zfs_get_snapused_int(zfs_handle_t *firstsnap, zfs_handle_t *lastsnap,
     uint64_t *usedp);
 extern uint64_t getprop_uint64(zfs_handle_t *, zfs_prop_t, char **);
@@ -462,10 +475,19 @@ extern void zfs_prune_proplist(zfs_handle_t *, uint8_t *);
 #define	ZFS_MOUNTPOINT_NONE	"none"
 #define	ZFS_MOUNTPOINT_LEGACY	"legacy"
 
+#define	ZFS_FEATURE_DISABLED	"disabled"
+#define	ZFS_FEATURE_ENABLED	"enabled"
+#define	ZFS_FEATURE_ACTIVE	"active"
+
+#define	ZFS_UNSUPPORTED_INACTIVE	"inactive"
+#define	ZFS_UNSUPPORTED_READONLY	"readonly"
+
 /*
  * zpool property management
  */
 extern int zpool_expand_proplist(zpool_handle_t *, zprop_list_t **);
+extern int zpool_prop_get_feature(zpool_handle_t *, const char *, char *,
+    size_t);
 extern const char *zpool_prop_default_string(zpool_prop_t);
 extern uint64_t zpool_prop_default_numeric(zpool_prop_t);
 extern const char *zpool_prop_column_name(zpool_prop_t);
diff --git a/include/sys/Makefile.am b/include/sys/Makefile.am
index 651e68b0c..a0cc9d1d6 100644
--- a/include/sys/Makefile.am
+++ b/include/sys/Makefile.am
@@ -6,6 +6,7 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/avl_impl.h \
 	$(top_srcdir)/include/sys/bplist.h \
 	$(top_srcdir)/include/sys/bpobj.h \
+	$(top_srcdir)/include/sys/bptree.h \
 	$(top_srcdir)/include/sys/dbuf.h \
 	$(top_srcdir)/include/sys/ddt.h \
 	$(top_srcdir)/include/sys/dmu.h \
@@ -53,6 +54,7 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/zap.h \
 	$(top_srcdir)/include/sys/zap_impl.h \
 	$(top_srcdir)/include/sys/zap_leaf.h \
+	$(top_srcdir)/include/sys/zfeature.h \
 	$(top_srcdir)/include/sys/zfs_acl.h \
 	$(top_srcdir)/include/sys/zfs_context.h \
 	$(top_srcdir)/include/sys/zfs_ctldir.h \
diff --git a/include/sys/bptree.h b/include/sys/bptree.h
new file mode 100644
index 000000000..971507211
--- /dev/null
+++ b/include/sys/bptree.h
@@ -0,0 +1,64 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
+
+#ifndef	_SYS_BPTREE_H
+#define	_SYS_BPTREE_H
+
+#include <sys/spa.h>
+#include <sys/zio.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+typedef struct bptree_phys {
+	uint64_t bt_begin;
+	uint64_t bt_end;
+	uint64_t bt_bytes;
+	uint64_t bt_comp;
+	uint64_t bt_uncomp;
+} bptree_phys_t;
+
+typedef struct bptree_entry_phys {
+	blkptr_t be_bp;
+	uint64_t be_birth_txg; /* only delete blocks born after this txg */
+	zbookmark_t be_zb; /* holds traversal resume point if needed */
+} bptree_entry_phys_t;
+
+typedef int bptree_itor_t(void *arg, const blkptr_t *bp, dmu_tx_t *tx);
+
+uint64_t bptree_alloc(objset_t *os, dmu_tx_t *tx);
+int bptree_free(objset_t *os, uint64_t obj, dmu_tx_t *tx);
+
+void bptree_add(objset_t *os, uint64_t obj, blkptr_t *bp, uint64_t birth_txg,
+    uint64_t bytes, uint64_t comp, uint64_t uncomp, dmu_tx_t *tx);
+
+int bptree_iterate(objset_t *os, uint64_t obj, boolean_t free,
+    bptree_itor_t func, void *arg, dmu_tx_t *tx);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _SYS_BPTREE_H */
diff --git a/include/sys/dmu.h b/include/sys/dmu.h
index fe317c835..ce3169731 100644
--- a/include/sys/dmu.h
+++ b/include/sys/dmu.h
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  */
 
@@ -71,6 +71,53 @@ typedef struct objset objset_t;
 typedef struct dmu_tx dmu_tx_t;
 typedef struct dsl_dir dsl_dir_t;
 
+typedef enum dmu_object_byteswap {
+	DMU_BSWAP_UINT8,
+	DMU_BSWAP_UINT16,
+	DMU_BSWAP_UINT32,
+	DMU_BSWAP_UINT64,
+	DMU_BSWAP_ZAP,
+	DMU_BSWAP_DNODE,
+	DMU_BSWAP_OBJSET,
+	DMU_BSWAP_ZNODE,
+	DMU_BSWAP_OLDACL,
+	DMU_BSWAP_ACL,
+	/*
+	 * Allocating a new byteswap type number makes the on-disk format
+	 * incompatible with any other format that uses the same number.
+	 *
+	 * Data can usually be structured to work with one of the
+	 * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
+	 */
+	DMU_BSWAP_NUMFUNCS
+} dmu_object_byteswap_t;
+
+#define	DMU_OT_NEWTYPE 0x80
+#define	DMU_OT_METADATA 0x40
+#define	DMU_OT_BYTESWAP_MASK 0x3f
+
+/*
+ * Defines a uint8_t object type. Object types specify if the data
+ * in the object is metadata (boolean) and how to byteswap the data
+ * (dmu_object_byteswap_t).
+ */
+#define	DMU_OT(byteswap, metadata) \
+	(DMU_OT_NEWTYPE | \
+	((metadata) ? DMU_OT_METADATA : 0) | \
+	((byteswap) & DMU_OT_BYTESWAP_MASK))
+
+#define	DMU_OT_IS_VALID(ot) (((ot) & DMU_OT_NEWTYPE) ? \
+	((ot) & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS : \
+	(ot) < DMU_OT_NUMTYPES)
+
+#define	DMU_OT_IS_METADATA(ot) (((ot) & DMU_OT_NEWTYPE) ? \
+	((ot) & DMU_OT_METADATA) : \
+	dmu_ot[(int)(ot)].ot_metadata)
+
+#define	DMU_OT_BYTESWAP(ot) (((ot) & DMU_OT_NEWTYPE) ? \
+	((ot) & DMU_OT_BYTESWAP_MASK) : \
+	dmu_ot[(int)(ot)].ot_byteswap)
+
 typedef enum dmu_object_type {
 	DMU_OT_NONE,
 	/* general: */
@@ -135,7 +182,35 @@ typedef enum dmu_object_type {
 	DMU_OT_DEADLIST_HDR,		/* UINT64 */
 	DMU_OT_DSL_CLONES,		/* ZAP */
 	DMU_OT_BPOBJ_SUBOBJ,		/* UINT64 */
-	DMU_OT_NUMTYPES
+	/*
+	 * Do not allocate new object types here. Doing so makes the on-disk
+	 * format incompatible with any other format that uses the same object
+	 * type number.
+	 *
+	 * When creating an object which does not have one of the above types
+	 * use the DMU_OTN_* type with the correct byteswap and metadata
+	 * values.
+	 *
+	 * The DMU_OTN_* types do not have entries in the dmu_ot table,
+	 * use the DMU_OT_IS_METDATA() and DMU_OT_BYTESWAP() macros instead
+	 * of indexing into dmu_ot directly (this works for both DMU_OT_* types
+	 * and DMU_OTN_* types).
+	 */
+	DMU_OT_NUMTYPES,
+
+	/*
+	 * Names for valid types declared with DMU_OT().
+	 */
+	DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE),
+	DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE),
+	DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE),
+	DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE),
+	DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE),
+	DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE),
+	DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE),
+	DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE),
+	DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE),
+	DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE),
 } dmu_object_type_t;
 
 typedef enum dmu_objset_type {
@@ -215,6 +290,9 @@ typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);
  */
 #define	DMU_POOL_DIRECTORY_OBJECT	1
 #define	DMU_POOL_CONFIG			"config"
+#define	DMU_POOL_FEATURES_FOR_WRITE	"features_for_write"
+#define	DMU_POOL_FEATURES_FOR_READ	"features_for_read"
+#define	DMU_POOL_FEATURE_DESCRIPTIONS	"feature_descriptions"
 #define	DMU_POOL_ROOT_DATASET		"root_dataset"
 #define	DMU_POOL_SYNC_BPOBJ		"sync_bplist"
 #define	DMU_POOL_ERRLOG_SCRUB		"errlog_scrub"
@@ -230,6 +308,7 @@ typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);
 #define	DMU_POOL_CREATION_VERSION	"creation_version"
 #define	DMU_POOL_SCAN			"scan"
 #define	DMU_POOL_FREE_BPOBJ		"free_bpobj"
+#define	DMU_POOL_BPTREE_OBJ		"bptree_obj"
 
 /*
  * Allocate an object from this objset.  The range of object numbers
@@ -490,7 +569,7 @@ void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
 
 /*
  * Free up the data blocks for a defined range of a file.  If size is
- * zero, the range from offset to end-of-file is freed.
+ * -1, the range from offset to end-of-file is freed.
  */
 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
 	uint64_t size, dmu_tx_t *tx);
@@ -564,12 +643,18 @@ typedef struct dmu_object_info {
 typedef void arc_byteswap_func_t(void *buf, size_t size);
 
 typedef struct dmu_object_type_info {
-	arc_byteswap_func_t	*ot_byteswap;
+	dmu_object_byteswap_t	ot_byteswap;
 	boolean_t		ot_metadata;
 	char			*ot_name;
 } dmu_object_type_info_t;
 
+typedef struct dmu_object_byteswap_info {
+	arc_byteswap_func_t	*ob_func;
+	char			*ob_name;
+} dmu_object_byteswap_info_t;
+
 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
+extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS];
 
 /*
  * Get information on a DMU object.
diff --git a/include/sys/dmu_traverse.h b/include/sys/dmu_traverse.h
index 5b326cd99..3cbf42f56 100644
--- a/include/sys/dmu_traverse.h
+++ b/include/sys/dmu_traverse.h
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef	_SYS_DMU_TRAVERSE_H
@@ -54,6 +55,9 @@ typedef int (blkptr_cb_t)(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
 
 int traverse_dataset(struct dsl_dataset *ds,
     uint64_t txg_start, int flags, blkptr_cb_t func, void *arg);
+int traverse_dataset_destroyed(spa_t *spa, blkptr_t *blkptr,
+    uint64_t txg_start, zbookmark_t *resume, int flags,
+    blkptr_cb_t func, void *arg);
 int traverse_pool(spa_t *spa,
     uint64_t txg_start, int flags, blkptr_cb_t func, void *arg);
 
diff --git a/include/sys/dsl_dataset.h b/include/sys/dsl_dataset.h
index 38ce3c567..547951cd0 100644
--- a/include/sys/dsl_dataset.h
+++ b/include/sys/dsl_dataset.h
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  */
 
@@ -86,7 +86,12 @@ typedef struct dsl_dataset_phys {
 	uint64_t ds_creation_time;	/* seconds since 1970 */
 	uint64_t ds_creation_txg;
 	uint64_t ds_deadlist_obj;	/* DMU_OT_DEADLIST */
-	uint64_t ds_used_bytes;
+	/*
+	 * ds_referenced_bytes, ds_compressed_bytes, and ds_uncompressed_bytes
+	 * include all blocks referenced by this dataset, including those
+	 * shared with any other datasets.
+	 */
+	uint64_t ds_referenced_bytes;
 	uint64_t ds_compressed_bytes;
 	uint64_t ds_uncompressed_bytes;
 	uint64_t ds_unique_bytes;	/* only relevant to snapshots */
diff --git a/include/sys/dsl_pool.h b/include/sys/dsl_pool.h
index 40e96101d..16fb98669 100644
--- a/include/sys/dsl_pool.h
+++ b/include/sys/dsl_pool.h
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef	_SYS_DSL_POOL_H
@@ -34,6 +35,7 @@
 #include <sys/ddt.h>
 #include <sys/arc.h>
 #include <sys/bpobj.h>
+#include <sys/bptree.h>
 
 #ifdef	__cplusplus
 extern "C" {
@@ -48,7 +50,8 @@ struct dsl_scan;
 
 /* These macros are for indexing into the zfs_all_blkstats_t. */
 #define	DMU_OT_DEFERRED	DMU_OT_NONE
-#define	DMU_OT_TOTAL	DMU_OT_NUMTYPES
+#define	DMU_OT_OTHER	DMU_OT_NUMTYPES /* place holder for DMU_OT() types */
+#define	DMU_OT_TOTAL	(DMU_OT_NUMTYPES + 1)
 
 typedef struct zfs_blkstat {
 	uint64_t	zb_count;
@@ -93,6 +96,7 @@ typedef struct dsl_pool {
 	uint64_t dp_write_limit;
 	uint64_t dp_tmp_userrefs_obj;
 	bpobj_t dp_free_bpobj;
+	uint64_t dp_bptree_obj;
 
 	struct dsl_scan *dp_scan;
 
@@ -121,7 +125,8 @@ typedef struct dsl_pool {
 	zfs_all_blkstats_t *dp_blkstats;
 } dsl_pool_t;
 
-int dsl_pool_open(spa_t *spa, uint64_t txg, dsl_pool_t **dpp);
+int dsl_pool_init(spa_t *spa, uint64_t txg, dsl_pool_t **dpp);
+int dsl_pool_open(dsl_pool_t *dp);
 void dsl_pool_close(dsl_pool_t *dp);
 dsl_pool_t *dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg);
 void dsl_pool_sync(dsl_pool_t *dp, uint64_t txg);
diff --git a/include/sys/dsl_scan.h b/include/sys/dsl_scan.h
index c79666e67..5691f4d14 100644
--- a/include/sys/dsl_scan.h
+++ b/include/sys/dsl_scan.h
@@ -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 @@ typedef struct dsl_scan {
 	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;
 
diff --git a/include/sys/fs/zfs.h b/include/sys/fs/zfs.h
index f72c74fc9..61596f7d7 100644
--- a/include/sys/fs/zfs.h
+++ b/include/sys/fs/zfs.h
@@ -170,6 +170,7 @@ typedef enum {
 	ZPOOL_PROP_ASHIFT,
 	ZPOOL_PROP_COMMENT,
 	ZPOOL_PROP_EXPANDSZ,
+	ZPOOL_PROP_FREEING,
 	ZPOOL_NUM_PROPS
 } zpool_prop_t;
 
@@ -244,6 +245,8 @@ const char *zpool_prop_to_name(zpool_prop_t);
 const char *zpool_prop_default_string(zpool_prop_t);
 uint64_t zpool_prop_default_numeric(zpool_prop_t);
 boolean_t zpool_prop_readonly(zpool_prop_t);
+boolean_t zpool_prop_feature(const char *);
+boolean_t zpool_prop_unsupported(const char *);
 int zpool_prop_index_to_string(zpool_prop_t, uint64_t, const char **);
 int zpool_prop_string_to_index(zpool_prop_t, const char *, uint64_t *);
 uint64_t zpool_prop_random_value(zpool_prop_t, uint64_t seed);
@@ -356,6 +359,7 @@ typedef enum {
 #define	SPA_VERSION_26			26ULL
 #define	SPA_VERSION_27			27ULL
 #define	SPA_VERSION_28			28ULL
+#define	SPA_VERSION_5000		5000ULL
 
 /*
  * When bumping up SPA_VERSION, make sure GRUB ZFS understands the on-disk
@@ -363,8 +367,8 @@ typedef enum {
  * and do the appropriate changes.  Also bump the version number in
  * usr/src/grub/capability.
  */
-#define	SPA_VERSION			SPA_VERSION_28
-#define	SPA_VERSION_STRING		"28"
+#define	SPA_VERSION			SPA_VERSION_5000
+#define	SPA_VERSION_STRING		"5000"
 
 /*
  * Symbolic names for the changes that caused a SPA_VERSION switch.
@@ -415,6 +419,12 @@ typedef enum {
 #define	SPA_VERSION_DEADLISTS		SPA_VERSION_26
 #define	SPA_VERSION_FAST_SNAP		SPA_VERSION_27
 #define	SPA_VERSION_MULTI_REPLACE	SPA_VERSION_28
+#define	SPA_VERSION_BEFORE_FEATURES	SPA_VERSION_28
+#define	SPA_VERSION_FEATURES		SPA_VERSION_5000
+
+#define	SPA_VERSION_IS_SUPPORTED(v) \
+	(((v) >= SPA_VERSION_INITIAL && (v) <= SPA_VERSION_BEFORE_FEATURES) || \
+	((v) >= SPA_VERSION_FEATURES && (v) <= SPA_VERSION))
 
 /*
  * ZPL version - rev'd whenever an incompatible on-disk format change
@@ -512,6 +522,11 @@ typedef struct zpool_rewind_policy {
 #define	ZPOOL_CONFIG_BOOTFS		"bootfs"	/* not stored on disk */
 #define	ZPOOL_CONFIG_MISSING_DEVICES	"missing_vdevs"	/* not stored on disk */
 #define	ZPOOL_CONFIG_LOAD_INFO		"load_info"	/* not stored on disk */
+#define	ZPOOL_CONFIG_REWIND_INFO	"rewind_info"	/* not stored on disk */
+#define	ZPOOL_CONFIG_UNSUP_FEAT		"unsup_feat"	/* not stored on disk */
+#define	ZPOOL_CONFIG_CAN_RDONLY		"can_rdonly"	/* not stored on disk */
+#define	ZPOOL_CONFIG_FEATURES_FOR_READ	"features_for_read"
+#define	ZPOOL_CONFIG_FEATURE_STATS	"feature_stats"	/* not stored on disk */
 /*
  * 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
@@ -590,6 +605,7 @@ typedef enum vdev_aux {
 	VDEV_AUX_BAD_LABEL,	/* the label is OK but invalid		*/
 	VDEV_AUX_VERSION_NEWER,	/* on-disk version is too new		*/
 	VDEV_AUX_VERSION_OLDER,	/* on-disk version is too old		*/
+	VDEV_AUX_UNSUP_FEAT,	/* unsupported features			*/
 	VDEV_AUX_SPARED,	/* hot spare used in another pool	*/
 	VDEV_AUX_ERR_EXCEEDED,	/* too many errors			*/
 	VDEV_AUX_IO_FAILURE,	/* experienced I/O failure		*/
diff --git a/include/sys/nvpair.h b/include/sys/nvpair.h
index 30ff4e066..cc399fd16 100644
--- a/include/sys/nvpair.h
+++ b/include/sys/nvpair.h
@@ -20,12 +20,14 @@
  */
 /*
  * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef	_SYS_NVPAIR_H
 #define	_SYS_NVPAIR_H
 
 #include <sys/types.h>
+#include <sys/time.h>
 #include <sys/errno.h>
 #include <sys/va_list.h>
 
@@ -274,6 +276,73 @@ int nvpair_value_hrtime(nvpair_t *, hrtime_t *);
 int nvpair_value_double(nvpair_t *, double *);
 #endif
 
+nvlist_t *fnvlist_alloc(void);
+void fnvlist_free(nvlist_t *);
+size_t fnvlist_size(nvlist_t *);
+char *fnvlist_pack(nvlist_t *, size_t *);
+void fnvlist_pack_free(char *, size_t);
+nvlist_t *fnvlist_unpack(char *, size_t);
+nvlist_t *fnvlist_dup(nvlist_t *);
+void fnvlist_merge(nvlist_t *, nvlist_t *);
+
+void fnvlist_add_boolean(nvlist_t *, const char *);
+void fnvlist_add_boolean_value(nvlist_t *, const char *, boolean_t);
+void fnvlist_add_byte(nvlist_t *, const char *, uchar_t);
+void fnvlist_add_int8(nvlist_t *, const char *, int8_t);
+void fnvlist_add_uint8(nvlist_t *, const char *, uint8_t);
+void fnvlist_add_int16(nvlist_t *, const char *, int16_t);
+void fnvlist_add_uint16(nvlist_t *, const char *, uint16_t);
+void fnvlist_add_int32(nvlist_t *, const char *, int32_t);
+void fnvlist_add_uint32(nvlist_t *, const char *, uint32_t);
+void fnvlist_add_int64(nvlist_t *, const char *, int64_t);
+void fnvlist_add_uint64(nvlist_t *, const char *, uint64_t);
+void fnvlist_add_string(nvlist_t *, const char *, const char *);
+void fnvlist_add_nvlist(nvlist_t *, const char *, nvlist_t *);
+void fnvlist_add_nvpair(nvlist_t *, nvpair_t *);
+void fnvlist_add_boolean_array(nvlist_t *, const char *, boolean_t *, uint_t);
+void fnvlist_add_byte_array(nvlist_t *, const char *, uchar_t *, uint_t);
+void fnvlist_add_int8_array(nvlist_t *, const char *, int8_t *, uint_t);
+void fnvlist_add_uint8_array(nvlist_t *, const char *, uint8_t *, uint_t);
+void fnvlist_add_int16_array(nvlist_t *, const char *, int16_t *, uint_t);
+void fnvlist_add_uint16_array(nvlist_t *, const char *, uint16_t *, uint_t);
+void fnvlist_add_int32_array(nvlist_t *, const char *, int32_t *, uint_t);
+void fnvlist_add_uint32_array(nvlist_t *, const char *, uint32_t *, uint_t);
+void fnvlist_add_int64_array(nvlist_t *, const char *, int64_t *, uint_t);
+void fnvlist_add_uint64_array(nvlist_t *, const char *, uint64_t *, uint_t);
+void fnvlist_add_string_array(nvlist_t *, const char *, char * const *, uint_t);
+void fnvlist_add_nvlist_array(nvlist_t *, const char *, nvlist_t **, uint_t);
+
+void fnvlist_remove(nvlist_t *, const char *);
+void fnvlist_remove_nvpair(nvlist_t *, nvpair_t *);
+
+nvpair_t *fnvlist_lookup_nvpair(nvlist_t *nvl, const char *name);
+boolean_t fnvlist_lookup_boolean(nvlist_t *nvl, const char *name);
+boolean_t fnvlist_lookup_boolean_value(nvlist_t *nvl, const char *name);
+uchar_t fnvlist_lookup_byte(nvlist_t *nvl, const char *name);
+int8_t fnvlist_lookup_int8(nvlist_t *nvl, const char *name);
+int16_t fnvlist_lookup_int16(nvlist_t *nvl, const char *name);
+int32_t fnvlist_lookup_int32(nvlist_t *nvl, const char *name);
+int64_t fnvlist_lookup_int64(nvlist_t *nvl, const char *name);
+uint8_t fnvlist_lookup_uint8(nvlist_t *nvl, const char *name);
+uint16_t fnvlist_lookup_uint16(nvlist_t *nvl, const char *name);
+uint32_t fnvlist_lookup_uint32(nvlist_t *nvl, const char *name);
+uint64_t fnvlist_lookup_uint64(nvlist_t *nvl, const char *name);
+char *fnvlist_lookup_string(nvlist_t *nvl, const char *name);
+nvlist_t *fnvlist_lookup_nvlist(nvlist_t *nvl, const char *name);
+
+boolean_t fnvpair_value_boolean_value(nvpair_t *nvp);
+uchar_t fnvpair_value_byte(nvpair_t *nvp);
+int8_t fnvpair_value_int8(nvpair_t *nvp);
+int16_t fnvpair_value_int16(nvpair_t *nvp);
+int32_t fnvpair_value_int32(nvpair_t *nvp);
+int64_t fnvpair_value_int64(nvpair_t *nvp);
+uint8_t fnvpair_value_uint8(nvpair_t *nvp);
+uint16_t fnvpair_value_uint16(nvpair_t *nvp);
+uint32_t fnvpair_value_uint32(nvpair_t *nvp);
+uint64_t fnvpair_value_uint64(nvpair_t *nvp);
+char *fnvpair_value_string(nvpair_t *nvp);
+nvlist_t *fnvpair_value_nvlist(nvpair_t *nvp);
+
 #ifdef	__cplusplus
 }
 #endif
diff --git a/include/sys/spa.h b/include/sys/spa.h
index 28bb4e1de..821172297 100644
--- a/include/sys/spa.h
+++ b/include/sys/spa.h
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  */
 
@@ -94,7 +94,7 @@ struct dsl_pool;
 /*
  * Size of block to hold the configuration data (a packed nvlist)
  */
-#define	SPA_CONFIG_BLOCKSIZE	(1 << 14)
+#define	SPA_CONFIG_BLOCKSIZE	(1ULL << 14)
 
 /*
  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
@@ -262,7 +262,7 @@ typedef struct blkptr {
 		DVA_GET_ASIZE(&(bp)->blk_dva[2]))
 
 #define	BP_GET_UCSIZE(bp) \
-	((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
+	((BP_GET_LEVEL(bp) > 0 || DMU_OT_IS_METADATA(BP_GET_TYPE(bp))) ? \
 	BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp))
 
 #define	BP_GET_NDVAS(bp)	\
@@ -404,8 +404,8 @@ typedef struct blkptr {
 #include <sys/dmu.h>
 
 #define	BP_GET_BUFC_TYPE(bp)						\
-	(((BP_GET_LEVEL(bp) > 0) || (dmu_ot[BP_GET_TYPE(bp)].ot_metadata)) ? \
-	ARC_BUFC_METADATA : ARC_BUFC_DATA);
+	(((BP_GET_LEVEL(bp) > 0) || (DMU_OT_IS_METADATA(BP_GET_TYPE(bp)))) ? \
+	ARC_BUFC_METADATA : ARC_BUFC_DATA)
 
 typedef enum spa_import_type {
 	SPA_IMPORT_EXISTING,
@@ -416,8 +416,8 @@ typedef enum spa_import_type {
 extern int spa_open(const char *pool, spa_t **, void *tag);
 extern int spa_open_rewind(const char *pool, spa_t **, void *tag,
     nvlist_t *policy, nvlist_t **config);
-extern int spa_get_stats(const char *pool, nvlist_t **config,
-    char *altroot, size_t buflen);
+extern int spa_get_stats(const char *pool, nvlist_t **config, char *altroot,
+    size_t buflen);
 extern int spa_create(const char *pool, nvlist_t *config, nvlist_t *props,
     const char *history_str, nvlist_t *zplprops);
 extern int spa_import_rootpool(char *devpath, char *devid);
@@ -574,6 +574,7 @@ extern void spa_claim_notify(zio_t *zio);
 /* Accessor functions */
 extern boolean_t spa_shutting_down(spa_t *spa);
 extern struct dsl_pool *spa_get_dsl(spa_t *spa);
+extern boolean_t spa_is_initializing(spa_t *spa);
 extern blkptr_t *spa_get_rootblkptr(spa_t *spa);
 extern void spa_set_rootblkptr(spa_t *spa, const blkptr_t *bp);
 extern void spa_altroot(spa_t *, char *, size_t);
@@ -605,6 +606,8 @@ extern uint64_t spa_delegation(spa_t *spa);
 extern objset_t *spa_meta_objset(spa_t *spa);
 
 /* Miscellaneous support routines */
+extern void spa_activate_mos_feature(spa_t *spa, const char *feature);
+extern void spa_deactivate_mos_feature(spa_t *spa, const char *feature);
 extern int spa_rename(const char *oldname, const char *newname);
 extern spa_t *spa_by_guid(uint64_t pool_guid, uint64_t device_guid);
 extern boolean_t spa_guid_exists(uint64_t pool_guid, uint64_t device_guid);
diff --git a/include/sys/spa_impl.h b/include/sys/spa_impl.h
index d367486a0..85a825d08 100644
--- a/include/sys/spa_impl.h
+++ b/include/sys/spa_impl.h
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  */
 
@@ -127,6 +127,7 @@ struct spa {
 	uint64_t	spa_import_flags;	/* import specific flags */
 	taskq_t		*spa_zio_taskq[ZIO_TYPES][ZIO_TASKQ_TYPES];
 	dsl_pool_t	*spa_dsl_pool;
+	boolean_t	spa_is_initializing;	/* true while opening pool */
 	metaslab_class_t *spa_normal_class;	/* normal data class */
 	metaslab_class_t *spa_log_class;	/* intent log data class */
 	uint64_t	spa_first_txg;		/* first txg after spa_open() */
@@ -144,6 +145,7 @@ struct spa {
 	list_t		spa_state_dirty_list;	/* vdevs with dirty state */
 	spa_aux_vdev_t	spa_spares;		/* hot spares */
 	spa_aux_vdev_t	spa_l2cache;		/* L2ARC cache devices */
+	nvlist_t	*spa_label_features;	/* Features for reading MOS */
 	uint64_t	spa_config_object;	/* MOS object for pool config */
 	uint64_t	spa_config_generation;	/* config generation number */
 	uint64_t	spa_syncing_txg;	/* txg currently syncing */
@@ -220,7 +222,10 @@ struct spa {
 	boolean_t	spa_autoreplace;	/* autoreplace set in open */
 	int		spa_vdev_locks;		/* locks grabbed */
 	uint64_t	spa_creation_version;	/* version at pool creation */
-	uint64_t	spa_prev_software_version;
+	uint64_t	spa_prev_software_version; /* See ub_software_version */
+	uint64_t	spa_feat_for_write_obj;	/* required to write to pool */
+	uint64_t	spa_feat_for_read_obj;	/* required to read from pool */
+	uint64_t	spa_feat_desc_obj;	/* Feature descriptions */
 	/*
 	 * spa_refcnt & spa_config_lock must be the last elements
 	 * because refcount_t changes size based on compilation options.
diff --git a/include/sys/vdev.h b/include/sys/vdev.h
index 005578398..51eb855ee 100644
--- a/include/sys/vdev.h
+++ b/include/sys/vdev.h
@@ -18,6 +18,7 @@
  *
  * CDDL HEADER END
  */
+
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012 by Delphix. All rights reserved.
@@ -140,8 +141,8 @@ extern nvlist_t *vdev_config_generate(spa_t *spa, vdev_t *vd,
 struct uberblock;
 extern uint64_t vdev_label_offset(uint64_t psize, int l, uint64_t offset);
 extern int vdev_label_number(uint64_t psise, uint64_t offset);
-extern nvlist_t *vdev_label_read_config(vdev_t *vd);
-extern void vdev_uberblock_load(zio_t *zio, vdev_t *vd, struct uberblock *ub);
+extern nvlist_t *vdev_label_read_config(vdev_t *vd, int label);
+extern void vdev_uberblock_load(vdev_t *, struct uberblock *, nvlist_t **);
 
 typedef enum {
 	VDEV_LABEL_CREATE,	/* create/add a new device */
diff --git a/include/sys/vdev_impl.h b/include/sys/vdev_impl.h
index 0b532dcdd..4133f2cf3 100644
--- a/include/sys/vdev_impl.h
+++ b/include/sys/vdev_impl.h
@@ -210,7 +210,7 @@ struct vdev {
 	 * For DTrace to work in userland (libzpool) context, these fields must
 	 * remain at the end of the structure.  DTrace will use the kernel's
 	 * CTF definition for 'struct vdev', and since the size of a kmutex_t is
-	 * larger in userland, the offsets for the rest fields would be
+	 * larger in userland, the offsets for the rest of the fields would be
 	 * incorrect.
 	 */
 	kmutex_t	vdev_dtl_lock;	/* vdev_dtl_{map,resilver}	*/
@@ -265,6 +265,7 @@ typedef struct vdev_label {
 #define	VDEV_LABEL_START_SIZE	(2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
 #define	VDEV_LABEL_END_SIZE	(2 * sizeof (vdev_label_t))
 #define	VDEV_LABELS		4
+#define	VDEV_BEST_LABEL		VDEV_LABELS
 
 #define	VDEV_ALLOC_LOAD		0
 #define	VDEV_ALLOC_ADD		1
diff --git a/include/sys/zap.h b/include/sys/zap.h
index 6237f8bf5..4d7b31559 100644
--- a/include/sys/zap.h
+++ b/include/sys/zap.h
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef	_SYS_ZAP_H
@@ -132,6 +133,8 @@ uint64_t zap_create_norm(objset_t *ds, int normflags, dmu_object_type_t ot,
 uint64_t zap_create_flags(objset_t *os, int normflags, zap_flags_t flags,
     dmu_object_type_t ot, int leaf_blockshift, int indirect_blockshift,
     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
+uint64_t zap_create_link(objset_t *os, dmu_object_type_t ot,
+    uint64_t parent_obj, const char *name, dmu_tx_t *tx);
 
 /*
  * Create a new zapobj with no attributes from the given (unallocated)
@@ -300,10 +303,6 @@ int zap_add_int_key(objset_t *os, uint64_t obj,
 int zap_lookup_int_key(objset_t *os, uint64_t obj,
     uint64_t key, uint64_t *valuep);
 
-/*
- * They name is a stringified version of key; increment its value by
- * delta.  Zero values will be zap_remove()-ed.
- */
 int zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta,
     dmu_tx_t *tx);
 
diff --git a/include/sys/zfeature.h b/include/sys/zfeature.h
new file mode 100644
index 000000000..9ff1c93df
--- /dev/null
+++ b/include/sys/zfeature.h
@@ -0,0 +1,52 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
+
+#ifndef _SYS_ZFEATURE_H
+#define	_SYS_ZFEATURE_H
+
+#include <sys/dmu.h>
+#include <sys/nvpair.h>
+#include "zfeature_common.h"
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+extern boolean_t feature_is_supported(objset_t *os, uint64_t obj,
+    uint64_t desc_obj, nvlist_t *unsup_feat);
+
+struct spa;
+extern void spa_feature_create_zap_objects(struct spa *, dmu_tx_t *);
+extern void spa_feature_enable(struct spa *, zfeature_info_t *, dmu_tx_t *);
+extern void spa_feature_incr(struct spa *, zfeature_info_t *, dmu_tx_t *);
+extern void spa_feature_decr(struct spa *, zfeature_info_t *, dmu_tx_t *);
+extern boolean_t spa_feature_is_enabled(struct spa *, zfeature_info_t *);
+extern boolean_t spa_feature_is_active(struct spa *, zfeature_info_t *);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif /* _SYS_ZFEATURE_H */
diff --git a/include/sys/zio.h b/include/sys/zio.h
index 289238c36..052797928 100644
--- a/include/sys/zio.h
+++ b/include/sys/zio.h
@@ -24,6 +24,7 @@
  */
 /*
  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef _ZIO_H
@@ -278,6 +279,14 @@ typedef struct zbookmark {
 #define	ZB_ZIL_OBJECT		(0ULL)
 #define	ZB_ZIL_LEVEL		(-2LL)
 
+#define	ZB_IS_ZERO(zb)						\
+	((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&	\
+	(zb)->zb_level == 0 && (zb)->zb_blkid == 0)
+#define	ZB_IS_ROOT(zb)				\
+	((zb)->zb_object == ZB_ROOT_OBJECT &&	\
+	(zb)->zb_level == ZB_ROOT_LEVEL &&	\
+	(zb)->zb_blkid == ZB_ROOT_BLKID)
+
 typedef struct zio_prop {
 	enum zio_checksum	zp_checksum;
 	enum zio_compress	zp_compress;
@@ -295,6 +304,7 @@ typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
 typedef void zio_cksum_free_f(void *cbdata, size_t size);
 
 struct zio_bad_cksum;				/* defined in zio_checksum.h */
+struct dnode_phys;
 
 struct zio_cksum_report {
 	struct zio_cksum_report *zcr_next;
@@ -567,6 +577,10 @@ extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
 /* Called from spa_sync(), but primarily an injection handler */
 extern void spa_handle_ignored_writes(spa_t *spa);
 
+/* zbookmark functions */
+boolean_t zbookmark_is_before(const struct dnode_phys *dnp,
+    const zbookmark_t *zb1, const zbookmark_t *zb2);
+
 #ifdef	__cplusplus
 }
 #endif
diff --git a/include/zfeature_common.h b/include/zfeature_common.h
new file mode 100644
index 000000000..27f8f00a0
--- /dev/null
+++ b/include/zfeature_common.h
@@ -0,0 +1,71 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
+
+#ifndef _ZFEATURE_COMMON_H
+#define	_ZFEATURE_COMMON_H
+
+#include <sys/fs/zfs.h>
+#include <sys/inttypes.h>
+#include <sys/types.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+struct zfeature_info;
+
+typedef struct zfeature_info {
+	const char *fi_uname;	/* User-facing feature name */
+	const char *fi_guid;	/* On-disk feature identifier */
+	const char *fi_desc;	/* Feature description */
+	boolean_t fi_can_readonly; /* Can open pool readonly w/o support? */
+	boolean_t fi_mos;	/* Is the feature necessary to read the MOS? */
+	struct zfeature_info **fi_depends; /* array; null terminated */
+} zfeature_info_t;
+
+typedef int (zfeature_func_t)(zfeature_info_t *fi, void *arg);
+
+#define	ZFS_FEATURE_DEBUG
+
+typedef enum spa_feature {
+	SPA_FEATURE_ASYNC_DESTROY,
+	SPA_FEATURES
+} spa_feature_t;
+
+extern zfeature_info_t spa_feature_table[SPA_FEATURES];
+
+extern boolean_t zfeature_is_valid_guid(const char *);
+
+extern boolean_t zfeature_is_supported(const char *);
+extern int zfeature_lookup_guid(const char *, zfeature_info_t **res);
+extern int zfeature_lookup_name(const char *, zfeature_info_t **res);
+
+extern void zpool_feature_init(void);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _ZFEATURE_COMMON_H */