Update ZFS from version 6 to 13 and bring some FreeBSD-specific changes.

This bring huge amount of changes, I'll enumerate only user-visible changes:

- Delegated Administration

	Allows regular users to perform ZFS operations, like file system
	creation, snapshot creation, etc.

- L2ARC

	Level 2 cache for ZFS - allows to use additional disks for cache.
	Huge performance improvements mostly for random read of mostly
	static content.

- slog

	Allow to use additional disks for ZFS Intent Log to speed up
	operations like fsync(2).

- vfs.zfs.super_owner

	Allows regular users to perform privileged operations on files stored
	on ZFS file systems owned by him. Very careful with this one.

- chflags(2)

	Not all the flags are supported. This still needs work.

- ZFSBoot

	Support to boot off of ZFS pool. Not finished, AFAIK.

	Submitted by:	dfr

- Snapshot properties

- New failure modes

	Before if write requested failed, system paniced. Now one
	can select from one of three failure modes:
	- panic - panic on write error
	- wait - wait for disk to reappear
	- continue - serve read requests if possible, block write requests

- Refquota, refreservation properties

	Just quota and reservation properties, but don't count space consumed
	by children file systems, clones and snapshots.

- Sparse volumes

	ZVOLs that don't reserve space in the pool.

- External attributes

	Compatible with extattr(2).

- NFSv4-ACLs

	Not sure about the status, might not be complete yet.

	Submitted by:	trasz

- Creation-time properties

- Regression tests for zpool(8) command.

Obtained from:	OpenSolaris

1 files changed, 13 insertions, 4 deletions

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/unique.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/unique.c
index b52e729..fbe7b61 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/unique.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/unique.c
@@ -19,7 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -30,8 +30,7 @@
 #include <sys/unique.h>
 
 static avl_tree_t unique_avl;
-static kmutex_t unique_mtx;	/* Lock never initialized. */
-SX_SYSINIT(unique, &unique_mtx, "unique lock");
+static kmutex_t unique_mtx;
 
 typedef struct unique {
 	avl_node_t un_link;
@@ -58,12 +57,22 @@ unique_init(void)
 {
 	avl_create(&unique_avl, unique_compare,
 	    sizeof (unique_t), offsetof(unique_t, un_link));
+	mutex_init(&unique_mtx, NULL, MUTEX_DEFAULT, NULL);
+}
+
+void
+unique_fini(void)
+{
+	avl_destroy(&unique_avl);
+	mutex_destroy(&unique_mtx);
 }
 
 uint64_t
 unique_create(void)
 {
-	return (unique_insert(0));
+	uint64_t value = unique_insert(0);
+	unique_remove(value);
+	return (value);
 }
 
 uint64_t