28 files changed, 379 insertions, 225 deletions

diff --git a/include/sys/Makefile.am b/include/sys/Makefile.am
index 2245ff445..34c715101 100644
--- a/include/sys/Makefile.am
+++ b/include/sys/Makefile.am
@@ -12,6 +12,7 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/dmu.h \
 	$(top_srcdir)/include/sys/dmu_impl.h \
 	$(top_srcdir)/include/sys/dmu_objset.h \
+	$(top_srcdir)/include/sys/dmu_send.h \
 	$(top_srcdir)/include/sys/dmu_traverse.h \
 	$(top_srcdir)/include/sys/dmu_tx.h \
 	$(top_srcdir)/include/sys/dmu_zfetch.h \
@@ -19,11 +20,13 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/dsl_dataset.h \
 	$(top_srcdir)/include/sys/dsl_deadlist.h \
 	$(top_srcdir)/include/sys/dsl_deleg.h \
+	$(top_srcdir)/include/sys/dsl_destroy.h \
 	$(top_srcdir)/include/sys/dsl_dir.h \
 	$(top_srcdir)/include/sys/dsl_pool.h \
 	$(top_srcdir)/include/sys/dsl_prop.h \
 	$(top_srcdir)/include/sys/dsl_scan.h \
 	$(top_srcdir)/include/sys/dsl_synctask.h \
+	$(top_srcdir)/include/sys/dsl_userhold.h \
 	$(top_srcdir)/include/sys/efi_partition.h \
 	$(top_srcdir)/include/sys/metaslab.h \
 	$(top_srcdir)/include/sys/metaslab_impl.h \
@@ -65,8 +68,8 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/zfs_sa.h \
 	$(top_srcdir)/include/sys/zfs_stat.h \
 	$(top_srcdir)/include/sys/zfs_vfsops.h \
-	$(top_srcdir)/include/sys/zfs_znode.h \
 	$(top_srcdir)/include/sys/zfs_vnops.h \
+	$(top_srcdir)/include/sys/zfs_znode.h \
 	$(top_srcdir)/include/sys/zil.h \
 	$(top_srcdir)/include/sys/zil_impl.h \
 	$(top_srcdir)/include/sys/zio_checksum.h \
diff --git a/include/sys/arc.h b/include/sys/arc.h
index 67882197a..8c10d947c 100644
--- a/include/sys/arc.h
+++ b/include/sys/arc.h
@@ -100,7 +100,7 @@ arc_buf_t *arc_loan_buf(spa_t *spa, int size);
 void arc_return_buf(arc_buf_t *buf, void *tag);
 void arc_loan_inuse_buf(arc_buf_t *buf, void *tag);
 void arc_buf_add_ref(arc_buf_t *buf, void *tag);
-int arc_buf_remove_ref(arc_buf_t *buf, void *tag);
+boolean_t arc_buf_remove_ref(arc_buf_t *buf, void *tag);
 int arc_buf_size(arc_buf_t *buf);
 void arc_release(arc_buf_t *buf, void *tag);
 int arc_released(arc_buf_t *buf);
diff --git a/include/sys/dbuf.h b/include/sys/dbuf.h
index 394fdfb15..8cd1fde01 100644
--- a/include/sys/dbuf.h
+++ b/include/sys/dbuf.h
@@ -307,20 +307,17 @@ void dbuf_fini(void);
 
 boolean_t dbuf_is_metadata(dmu_buf_impl_t *db);
 
-#define	DBUF_IS_METADATA(_db)	\
-	(dbuf_is_metadata(_db))
-
 #define	DBUF_GET_BUFC_TYPE(_db)	\
-	(DBUF_IS_METADATA(_db) ? ARC_BUFC_METADATA : ARC_BUFC_DATA)
+	(dbuf_is_metadata(_db) ? ARC_BUFC_METADATA : ARC_BUFC_DATA)
 
 #define	DBUF_IS_CACHEABLE(_db)						\
 	((_db)->db_objset->os_primary_cache == ZFS_CACHE_ALL ||		\
-	(DBUF_IS_METADATA(_db) &&					\
+	(dbuf_is_metadata(_db) &&					\
 	((_db)->db_objset->os_primary_cache == ZFS_CACHE_METADATA)))
 
 #define	DBUF_IS_L2CACHEABLE(_db)					\
 	((_db)->db_objset->os_secondary_cache == ZFS_CACHE_ALL ||	\
-	(DBUF_IS_METADATA(_db) &&					\
+	(dbuf_is_metadata(_db) &&					\
 	((_db)->db_objset->os_secondary_cache == ZFS_CACHE_METADATA)))
 
 #define	DBUF_IS_L2COMPRESSIBLE(_db)					\
diff --git a/include/sys/dmu.h b/include/sys/dmu.h
index c50df391e..b0db7604d 100644
--- a/include/sys/dmu.h
+++ b/include/sys/dmu.h
@@ -214,6 +214,11 @@ typedef enum dmu_object_type {
 	DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE),
 } dmu_object_type_t;
 
+typedef enum txg_how {
+	TXG_WAIT = 1,
+	TXG_NOWAIT,
+} txg_how_t;
+
 void byteswap_uint64_array(void *buf, size_t size);
 void byteswap_uint32_array(void *buf, size_t size);
 void byteswap_uint16_array(void *buf, size_t size);
@@ -252,22 +257,19 @@ void dmu_objset_rele(objset_t *os, void *tag);
 void dmu_objset_disown(objset_t *os, void *tag);
 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp);
 
-int dmu_objset_evict_dbufs(objset_t *os);
+void dmu_objset_evict_dbufs(objset_t *os);
 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
     void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg);
-int dmu_objset_clone(const char *name, struct dsl_dataset *clone_origin,
-    uint64_t flags);
-int dmu_objset_destroy(const char *name, boolean_t defer);
-int dmu_snapshots_destroy_nvl(struct nvlist *snaps, boolean_t defer,
+int dmu_objset_clone(const char *name, const char *origin);
+int dsl_destroy_snapshots_nvl(struct nvlist *snaps, boolean_t defer,
     struct nvlist *errlist);
-int dmu_objset_snapshot(struct nvlist *snaps, struct nvlist *, struct nvlist *);
 int dmu_objset_snapshot_one(const char *fsname, const char *snapname);
 int dmu_objset_snapshot_tmp(const char *, const char *, int);
-int dmu_objset_rename(const char *name, const char *newname,
-    boolean_t recursive);
 int dmu_objset_find(char *name, int func(const char *, void *), void *arg,
     int flags);
 void dmu_objset_byteswap(void *buf, size_t size);
+int dsl_dataset_rename_snapshot(const char *fsname,
+    const char *oldsnapname, const char *newsnapname, boolean_t recursive);
 
 typedef struct dmu_buf {
 	uint64_t db_object;		/* object that this buffer is part of */
@@ -537,7 +539,7 @@ void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
 void dmu_tx_abort(dmu_tx_t *tx);
-int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
+int dmu_tx_assign(dmu_tx_t *tx, enum txg_how txg_how);
 void dmu_tx_wait(dmu_tx_t *tx);
 void dmu_tx_commit(dmu_tx_t *tx);
 
@@ -785,36 +787,8 @@ typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
     dmu_traverse_cb_t cb, void *arg);
 
-int dmu_send(objset_t *tosnap, objset_t *fromsnap,
-    int outfd, struct vnode *vp, offset_t *off);
-int dmu_send_estimate(objset_t *tosnap, objset_t *fromsnap, uint64_t *sizep);
-
-typedef struct dmu_recv_cookie {
-	/*
-	 * This structure is opaque!
-	 *
-	 * If logical and real are different, we are recving the stream
-	 * into the "real" temporary clone, and then switching it with
-	 * the "logical" target.
-	 */
-	struct dsl_dataset *drc_logical_ds;
-	struct dsl_dataset *drc_real_ds;
-	struct drr_begin *drc_drrb;
-	char *drc_tosnap;
-	char *drc_top_ds;
-	boolean_t drc_newfs;
-	boolean_t drc_force;
-	struct avl_tree *drc_guid_to_ds_map;
-} dmu_recv_cookie_t;
-
-int dmu_recv_begin(char *tofs, char *tosnap, char *topds, struct drr_begin *,
-    boolean_t force, objset_t *origin, dmu_recv_cookie_t *);
-int dmu_recv_stream(dmu_recv_cookie_t *drc, struct vnode *vp, offset_t *voffp,
-    int cleanup_fd, uint64_t *action_handlep);
-int dmu_recv_end(dmu_recv_cookie_t *drc);
-
-int dmu_diff(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp,
-    offset_t *off);
+int dmu_diff(const char *tosnap_name, const char *fromsnap_name,
+    struct vnode *vp, offset_t *offp);
 
 /* CRC64 table */
 #define	ZFS_CRC64_POLY	0xC96C5795D7870F42ULL	/* ECMA-182, reflected form */
diff --git a/include/sys/dmu_objset.h b/include/sys/dmu_objset.h
index 79d3a6bc0..7fe91bebe 100644
--- a/include/sys/dmu_objset.h
+++ b/include/sys/dmu_objset.h
@@ -44,6 +44,7 @@ extern "C" {
 
 extern krwlock_t os_lock;
 
+struct dsl_pool;
 struct dsl_dataset;
 struct dmu_tx;
 
@@ -115,8 +116,6 @@ struct objset {
 	/* stuff we store for the user */
 	kmutex_t os_user_ptr_lock;
 	void *os_user_ptr;
-
-	/* SA layout/attribute registration */
 	sa_os_t *os_sa;
 };
 
@@ -146,10 +145,10 @@ void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
     uint64_t *usedobjsp, uint64_t *availobjsp);
 uint64_t dmu_objset_fsid_guid(objset_t *os);
-int dmu_objset_find_spa(spa_t *spa, const char *name,
-    int func(spa_t *, uint64_t, const char *, void *), void *arg, int flags);
-int dmu_objset_prefetch(const char *name, void *arg);
-int dmu_objset_evict_dbufs(objset_t *os);
+int dmu_objset_find_dp(struct dsl_pool *dp, uint64_t ddobj,
+    int func(struct dsl_pool *, struct dsl_dataset *, void *),
+    void *arg, int flags);
+void dmu_objset_evict_dbufs(objset_t *os);
 timestruc_t dmu_objset_snap_cmtime(objset_t *os);
 
 /* called from dsl */
@@ -165,6 +164,7 @@ void dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx);
 boolean_t dmu_objset_userused_enabled(objset_t *os);
 int dmu_objset_userspace_upgrade(objset_t *os);
 boolean_t dmu_objset_userspace_present(objset_t *os);
+int dmu_fsname(const char *snapname, char *buf);
 
 void dmu_objset_init(void);
 void dmu_objset_fini(void);
diff --git a/include/sys/dmu_send.h b/include/sys/dmu_send.h
new file mode 100644
index 000000000..ee0885a60
--- /dev/null
+++ b/include/sys/dmu_send.h
@@ -0,0 +1,66 @@
+/*
+ * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ */
+
+#ifndef _DMU_SEND_H
+#define	_DMU_SEND_H
+
+#include <sys/inttypes.h>
+#include <sys/spa.h>
+
+struct vnode;
+struct dsl_dataset;
+struct drr_begin;
+struct avl_tree;
+
+int dmu_send(const char *tosnap, const char *fromsnap, int outfd,
+    struct vnode *vp, offset_t *off);
+int dmu_send_estimate(struct dsl_dataset *ds, struct dsl_dataset *fromds,
+    uint64_t *sizep);
+int dmu_send_obj(const char *pool, uint64_t tosnap, uint64_t fromsnap,
+    int outfd, struct vnode *vp, offset_t *off);
+
+typedef struct dmu_recv_cookie {
+	struct dsl_dataset *drc_ds;
+	struct drr_begin *drc_drrb;
+	const char *drc_tofs;
+	const char *drc_tosnap;
+	boolean_t drc_newfs;
+	boolean_t drc_byteswap;
+	boolean_t drc_force;
+	struct avl_tree *drc_guid_to_ds_map;
+	zio_cksum_t drc_cksum;
+	uint64_t drc_newsnapobj;
+} dmu_recv_cookie_t;
+
+int dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *drrb,
+    boolean_t force, char *origin, dmu_recv_cookie_t *drc);
+int dmu_recv_stream(dmu_recv_cookie_t *drc, struct vnode *vp, offset_t *voffp,
+    int cleanup_fd, uint64_t *action_handlep);
+int dmu_recv_end(dmu_recv_cookie_t *drc);
+
+#endif /* _DMU_SEND_H */
diff --git a/include/sys/dmu_tx.h b/include/sys/dmu_tx.h
index 40c1ded5d..48a507e34 100644
--- a/include/sys/dmu_tx.h
+++ b/include/sys/dmu_tx.h
@@ -22,6 +22,9 @@
  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
 
 #ifndef	_SYS_DMU_TX_H
 #define	_SYS_DMU_TX_H
@@ -133,10 +136,11 @@ extern dmu_tx_stats_t dmu_tx_stats;
  * These routines are defined in dmu.h, and are called by the user.
  */
 dmu_tx_t *dmu_tx_create(objset_t *dd);
-int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
+int dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how);
 void dmu_tx_commit(dmu_tx_t *tx);
 void dmu_tx_abort(dmu_tx_t *tx);
 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
+struct dsl_pool *dmu_tx_pool(dmu_tx_t *tx);
 void dmu_tx_wait(dmu_tx_t *tx);
 
 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
diff --git a/include/sys/dsl_dataset.h b/include/sys/dsl_dataset.h
index 735ccbbd3..494f11b90 100644
--- a/include/sys/dsl_dataset.h
+++ b/include/sys/dsl_dataset.h
@@ -35,6 +35,7 @@
 #include <sys/dsl_synctask.h>
 #include <sys/zfs_context.h>
 #include <sys/dsl_deadlist.h>
+#include <sys/refcount.h>
 
 #ifdef	__cplusplus
 extern "C" {
@@ -48,10 +49,8 @@ struct dsl_pool;
 #define	DS_IS_INCONSISTENT(ds)	\
 	((ds)->ds_phys->ds_flags & DS_FLAG_INCONSISTENT)
 /*
- * NB: nopromote can not yet be set, but we want support for it in this
- * on-disk version, so that we don't need to upgrade for it later.  It
- * will be needed when we implement 'zfs split' (where the split off
- * clone should not be promoted).
+ * Note: nopromote can not yet be set, but we want support for it in this
+ * on-disk version, so that we don't need to upgrade for it later.
  */
 #define	DS_FLAG_NOPROMOTE	(1ULL<<1)
 
@@ -76,6 +75,8 @@ struct dsl_pool;
  */
 #define	DS_FLAG_CI_DATASET	(1ULL<<16)
 
+#define	DS_CREATE_FLAG_NODIRTY	(1ULL<<24)
+
 typedef struct dsl_dataset_phys {
 	uint64_t ds_dir_obj;		/* DMU_OT_DSL_DIR */
 	uint64_t ds_prev_snap_obj;	/* DMU_OT_DSL_DATASET */
@@ -125,9 +126,6 @@ typedef struct dsl_dataset {
 	dsl_deadlist_t ds_deadlist;
 	bplist_t ds_pending_deadlist;
 
-	/* to protect against multiple concurrent incremental recv */
-	kmutex_t ds_recvlock;
-
 	/* protected by lock on pool's dp_dirty_datasets list */
 	txg_node_t ds_dirty_link;
 	list_node_t ds_synced_link;
@@ -139,13 +137,15 @@ typedef struct dsl_dataset {
 	kmutex_t ds_lock;
 	objset_t *ds_objset;
 	uint64_t ds_userrefs;
+	void *ds_owner;
 
 	/*
-	 * ds_owner is protected by the ds_rwlock and the ds_lock
+	 * Long holds prevent the ds from being destroyed; they allow the
+	 * ds to remain held even after dropping the dp_config_rwlock.
+	 * Owning counts as a long hold.  See the comments above
+	 * dsl_pool_hold() for details.
 	 */
-	krwlock_t ds_rwlock;
-	kcondvar_t ds_exclusive_cv;
-	void *ds_owner;
+	refcount_t ds_longholds;
 
 	/* no locking; only for making guesses */
 	uint64_t ds_trysnap_txg;
@@ -163,76 +163,42 @@ typedef struct dsl_dataset {
 	char ds_snapname[MAXNAMELEN];
 } dsl_dataset_t;
 
-struct dsl_ds_destroyarg {
-	dsl_dataset_t *ds;		/* ds to destroy */
-	dsl_dataset_t *rm_origin;	/* also remove our origin? */
-	boolean_t is_origin_rm;		/* set if removing origin snap */
-	boolean_t defer;		/* destroy -d requested? */
-	boolean_t releasing;		/* destroying due to release? */
-	boolean_t need_prep;		/* do we need to retry due to EBUSY? */
-};
-
 /*
  * The max length of a temporary tag prefix is the number of hex digits
  * required to express UINT64_MAX plus one for the hyphen.
  */
 #define	MAX_TAG_PREFIX_LEN	17
 
-struct dsl_ds_holdarg {
-	dsl_sync_task_group_t *dstg;
-	const char *htag;
-	char *snapname;
-	boolean_t recursive;
-	boolean_t gotone;
-	boolean_t temphold;
-	char failed[MAXPATHLEN];
-};
-
 #define	dsl_dataset_is_snapshot(ds) \
 	((ds)->ds_phys->ds_num_children != 0)
 
 #define	DS_UNIQUE_IS_ACCURATE(ds)	\
 	(((ds)->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
 
-int dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp);
-int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj,
-    void *tag, dsl_dataset_t **);
-int dsl_dataset_own(const char *name, boolean_t inconsistentok,
+int dsl_dataset_hold(struct dsl_pool *dp, const char *name, void *tag,
+    dsl_dataset_t **dsp);
+int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj, void *tag,
+    dsl_dataset_t **);
+void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
+int dsl_dataset_own(struct dsl_pool *dp, const char *name,
     void *tag, dsl_dataset_t **dsp);
 int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
-    boolean_t inconsistentok, void *tag, dsl_dataset_t **dsp);
-void dsl_dataset_name(dsl_dataset_t *ds, char *name);
-void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
+    void *tag, dsl_dataset_t **dsp);
 void dsl_dataset_disown(dsl_dataset_t *ds, void *tag);
-void dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag);
-boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok,
-    void *tag);
-void dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *tag);
+void dsl_dataset_name(dsl_dataset_t *ds, char *name);
+boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, void *tag);
 void dsl_register_onexit_hold_cleanup(dsl_dataset_t *ds, const char *htag,
     minor_t minor);
 uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
     dsl_dataset_t *origin, uint64_t flags, cred_t *, dmu_tx_t *);
 uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
     uint64_t flags, dmu_tx_t *tx);
-int dsl_dataset_destroy(dsl_dataset_t *ds, void *tag, boolean_t defer);
-dsl_checkfunc_t dsl_dataset_destroy_check;
-dsl_syncfunc_t dsl_dataset_destroy_sync;
-dsl_syncfunc_t dsl_dataset_user_hold_sync;
-int dsl_dataset_snapshot_check(dsl_dataset_t *ds, const char *, dmu_tx_t *tx);
-void dsl_dataset_snapshot_sync(dsl_dataset_t *ds, const char *, dmu_tx_t *tx);
-int dsl_dataset_rename(char *name, const char *newname, boolean_t recursive);
+int dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors);
 int dsl_dataset_promote(const char *name, char *conflsnap);
-int dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
-    boolean_t force);
-int dsl_dataset_user_hold(char *dsname, char *snapname, char *htag,
-    boolean_t recursive, boolean_t temphold, int cleanup_fd);
-int dsl_dataset_user_hold_for_send(dsl_dataset_t *ds, char *htag,
-    boolean_t temphold);
-int dsl_dataset_user_release(char *dsname, char *snapname, char *htag,
-    boolean_t recursive);
-int dsl_dataset_user_release_tmp(struct dsl_pool *dp, uint64_t dsobj,
-    char *htag, boolean_t retry);
-int dsl_dataset_get_holds(const char *dsname, nvlist_t **nvp);
+int dsl_dataset_rename_snapshot(const char *fsname,
+    const char *oldsnapname, const char *newsnapname, boolean_t recursive);
+int dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
+    minor_t cleanup_minor, const char *htag);
 
 blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
 void dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx);
@@ -271,13 +237,35 @@ int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
 int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
     uint64_t asize, uint64_t inflight, uint64_t *used,
     uint64_t *ref_rsrv);
-int dsl_dataset_set_quota(const char *dsname, zprop_source_t source,
+int dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
     uint64_t quota);
-dsl_syncfunc_t dsl_dataset_set_quota_sync;
-int dsl_dataset_set_reservation(const char *dsname, zprop_source_t source,
+int dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
     uint64_t reservation);
 
-int dsl_destroy_inconsistent(const char *dsname, void *arg);
+boolean_t dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier);
+void dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag);
+void dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag);
+boolean_t dsl_dataset_long_held(dsl_dataset_t *ds);
+
+int dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
+    dsl_dataset_t *origin_head, boolean_t force);
+void dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
+    dsl_dataset_t *origin_head, dmu_tx_t *tx);
+int dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
+    dmu_tx_t *tx);
+void dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
+    dmu_tx_t *tx);
+
+void dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
+    dmu_tx_t *tx);
+void dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds);
+int dsl_dataset_get_snapname(dsl_dataset_t *ds);
+int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
+    uint64_t *value);
+int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx);
+void dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
+    zprop_source_t source, uint64_t value, dmu_tx_t *tx);
+int dsl_dataset_rollback(const char *fsname);
 
 #ifdef ZFS_DEBUG
 #define	dprintf_ds(ds, fmt, ...) do { \
diff --git a/include/sys/dsl_destroy.h b/include/sys/dsl_destroy.h
new file mode 100644
index 000000000..c5a70bb90
--- /dev/null
+++ b/include/sys/dsl_destroy.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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ */
+
+#ifndef	_SYS_DSL_DESTROY_H
+#define	_SYS_DSL_DESTROY_H
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+struct nvlist;
+struct dsl_dataset;
+struct dmu_tx;
+
+int dsl_destroy_snapshots_nvl(struct nvlist *snaps, boolean_t defer,
+    struct nvlist *errlist);
+int dsl_destroy_snapshot(const char *name, boolean_t defer);
+int dsl_destroy_head(const char *name);
+int dsl_destroy_head_check_impl(struct dsl_dataset *ds, int expected_holds);
+void dsl_destroy_head_sync_impl(struct dsl_dataset *ds, struct dmu_tx *tx);
+int dsl_destroy_inconsistent(const char *dsname, void *arg);
+void dsl_destroy_snapshot_sync_impl(struct dsl_dataset *ds,
+    boolean_t defer, struct dmu_tx *tx);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif /* _SYS_DSL_DESTROY_H */
diff --git a/include/sys/dsl_dir.h b/include/sys/dsl_dir.h
index 65ad202bb..2477e89af 100644
--- a/include/sys/dsl_dir.h
+++ b/include/sys/dsl_dir.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_DIR_H
@@ -101,18 +102,15 @@ struct dsl_dir {
 	char dd_myname[MAXNAMELEN];
 };
 
-void dsl_dir_close(dsl_dir_t *dd, void *tag);
-int dsl_dir_open(const char *name, void *tag, dsl_dir_t **, const char **tail);
-int dsl_dir_open_spa(spa_t *spa, const char *name, void *tag, dsl_dir_t **,
-    const char **tailp);
-int dsl_dir_open_obj(dsl_pool_t *dp, uint64_t ddobj,
+void dsl_dir_rele(dsl_dir_t *dd, void *tag);
+int dsl_dir_hold(dsl_pool_t *dp, const char *name, void *tag,
+    dsl_dir_t **, const char **tail);
+int dsl_dir_hold_obj(dsl_pool_t *dp, uint64_t ddobj,
     const char *tail, void *tag, dsl_dir_t **);
 void dsl_dir_name(dsl_dir_t *dd, char *buf);
 int dsl_dir_namelen(dsl_dir_t *dd);
 uint64_t dsl_dir_create_sync(dsl_pool_t *dp, dsl_dir_t *pds,
     const char *name, dmu_tx_t *tx);
-dsl_checkfunc_t dsl_dir_destroy_check;
-dsl_syncfunc_t dsl_dir_destroy_sync;
 void dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv);
 uint64_t dsl_dir_space_available(dsl_dir_t *dd,
     dsl_dir_t *ancestor, int64_t delta, int ondiskonly);
@@ -131,14 +129,15 @@ int dsl_dir_set_quota(const char *ddname, zprop_source_t source,
     uint64_t quota);
 int dsl_dir_set_reservation(const char *ddname, zprop_source_t source,
     uint64_t reservation);
-int dsl_dir_rename(dsl_dir_t *dd, const char *newname);
+int dsl_dir_rename(const char *oldname, const char *newname);
 int dsl_dir_transfer_possible(dsl_dir_t *sdd, dsl_dir_t *tdd, uint64_t space);
-int dsl_dir_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx);
 boolean_t dsl_dir_is_clone(dsl_dir_t *dd);
 void dsl_dir_new_refreservation(dsl_dir_t *dd, struct dsl_dataset *ds,
     uint64_t reservation, cred_t *cr, dmu_tx_t *tx);
 void dsl_dir_snap_cmtime_update(dsl_dir_t *dd);
 timestruc_t dsl_dir_snap_cmtime(dsl_dir_t *dd);
+void dsl_dir_set_reservation_sync_impl(dsl_dir_t *dd, uint64_t value,
+    dmu_tx_t *tx);
 
 /* internal reserved dir name */
 #define	MOS_DIR_NAME "$MOS"
diff --git a/include/sys/dsl_pool.h b/include/sys/dsl_pool.h
index 4a4bf76ef..51b588e6a 100644
--- a/include/sys/dsl_pool.h
+++ b/include/sys/dsl_pool.h
@@ -36,6 +36,7 @@
 #include <sys/arc.h>
 #include <sys/bpobj.h>
 #include <sys/bptree.h>
+#include <sys/rrwlock.h>
 
 #ifdef	__cplusplus
 extern "C" {
@@ -129,7 +130,7 @@ typedef struct dsl_pool {
 	 * syncing context does not need to ever have it for read, since
 	 * nobody else could possibly have it for write.
 	 */
-	krwlock_t dp_config_rwlock;
+	rrwlock_t dp_config_rwlock;
 
 	zfs_all_blkstats_t *dp_blkstats;
 } dsl_pool_t;
@@ -155,15 +156,20 @@ void dsl_pool_upgrade_clones(dsl_pool_t *dp, dmu_tx_t *tx);
 void dsl_pool_upgrade_dir_clones(dsl_pool_t *dp, dmu_tx_t *tx);
 void dsl_pool_mos_diduse_space(dsl_pool_t *dp,
     int64_t used, int64_t comp, int64_t uncomp);
+void dsl_pool_config_enter(dsl_pool_t *dp, void *tag);
+void dsl_pool_config_exit(dsl_pool_t *dp, void *tag);
+boolean_t dsl_pool_config_held(dsl_pool_t *dp);
 
 taskq_t *dsl_pool_iput_taskq(dsl_pool_t *dp);
 
-extern int dsl_pool_user_hold(dsl_pool_t *dp, uint64_t dsobj,
-    const char *tag, uint64_t *now, dmu_tx_t *tx);
-extern int dsl_pool_user_release(dsl_pool_t *dp, uint64_t dsobj,
+int dsl_pool_user_hold(dsl_pool_t *dp, uint64_t dsobj,
+    const char *tag, uint64_t now, dmu_tx_t *tx);
+int dsl_pool_user_release(dsl_pool_t *dp, uint64_t dsobj,
     const char *tag, dmu_tx_t *tx);
-extern void dsl_pool_clean_tmp_userrefs(dsl_pool_t *dp);
+void dsl_pool_clean_tmp_userrefs(dsl_pool_t *dp);
 int dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **);
+int dsl_pool_hold(const char *name, void *tag, dsl_pool_t **dp);
+void dsl_pool_rele(dsl_pool_t *dp, void *tag);
 
 void dsl_pool_tx_assign_add_usecs(dsl_pool_t *dp, uint64_t usecs);
 
diff --git a/include/sys/dsl_prop.h b/include/sys/dsl_prop.h
index b0d9a52cd..5fe18d6a7 100644
--- a/include/sys/dsl_prop.h
+++ b/include/sys/dsl_prop.h
@@ -54,58 +54,47 @@ typedef struct dsl_props_arg {
 	zprop_source_t pa_source;
 } dsl_props_arg_t;
 
-typedef struct dsl_prop_set_arg {
-	const char *psa_name;
-	zprop_source_t psa_source;
-	int psa_intsz;
-	int psa_numints;
-	const void *psa_value;
-
-	/*
-	 * Used to handle the special requirements of the quota and reservation
-	 * properties.
-	 */
-	uint64_t psa_effective_value;
-} dsl_prop_setarg_t;
-
 int dsl_prop_register(struct dsl_dataset *ds, const char *propname,
     dsl_prop_changed_cb_t *callback, void *cbarg);
 int dsl_prop_unregister(struct dsl_dataset *ds, const char *propname,
     dsl_prop_changed_cb_t *callback, void *cbarg);
-int dsl_prop_numcb(struct dsl_dataset *ds);
+void dsl_prop_notify_all(struct dsl_dir *dd);
+boolean_t dsl_prop_hascb(struct dsl_dataset *ds);
 
 int dsl_prop_get(const char *ddname, const char *propname,
     int intsz, int numints, void *buf, char *setpoint);
 int dsl_prop_get_integer(const char *ddname, const char *propname,
     uint64_t *valuep, char *setpoint);
 int dsl_prop_get_all(objset_t *os, nvlist_t **nvp);
-int dsl_prop_get_received(objset_t *os, nvlist_t **nvp);
+int dsl_prop_get_received(const char *dsname, nvlist_t **nvp);
 int dsl_prop_get_ds(struct dsl_dataset *ds, const char *propname,
     int intsz, int numints, void *buf, char *setpoint);
+int dsl_prop_get_int_ds(struct dsl_dataset *ds, const char *propname,
+    uint64_t *valuep);
 int dsl_prop_get_dd(struct dsl_dir *dd, const char *propname,
     int intsz, int numints, void *buf, char *setpoint,
     boolean_t snapshot);
 
-dsl_syncfunc_t dsl_props_set_sync;
-int dsl_prop_set(const char *ddname, const char *propname,
-    zprop_source_t source, int intsz, int numints, const void *buf);
+void dsl_props_set_sync_impl(struct dsl_dataset *ds, zprop_source_t source,
+    nvlist_t *props, dmu_tx_t *tx);
+void dsl_prop_set_sync_impl(struct dsl_dataset *ds, const char *propname,
+    zprop_source_t source, int intsz, int numints, const void *value,
+    dmu_tx_t *tx);
 int dsl_props_set(const char *dsname, zprop_source_t source, nvlist_t *nvl);
+int dsl_prop_set_int(const char *dsname, const char *propname,
+    zprop_source_t source, uint64_t value);
+int dsl_prop_set_string(const char *dsname, const char *propname,
+    zprop_source_t source, const char *value);
+int dsl_prop_inherit(const char *dsname, const char *propname,
+    zprop_source_t source);
 
-void dsl_prop_setarg_init_uint64(dsl_prop_setarg_t *psa, const char *propname,
-    zprop_source_t source, uint64_t *value);
-int dsl_prop_predict_sync(dsl_dir_t *dd, dsl_prop_setarg_t *psa);
-#ifdef	ZFS_DEBUG
-void dsl_prop_check_prediction(dsl_dir_t *dd, dsl_prop_setarg_t *psa);
-#define	DSL_PROP_CHECK_PREDICTION(dd, psa)	\
-	dsl_prop_check_prediction((dd), (psa))
-#else
-#define	DSL_PROP_CHECK_PREDICTION(dd, psa)	/* nothing */
-#endif
+int dsl_prop_predict(dsl_dir_t *dd, const char *propname,
+    zprop_source_t source, uint64_t value, uint64_t *newvalp);
 
 /* flag first receive on or after SPA_VERSION_RECVD_PROPS */
-boolean_t dsl_prop_get_hasrecvd(objset_t *os);
-void dsl_prop_set_hasrecvd(objset_t *os);
-void dsl_prop_unset_hasrecvd(objset_t *os);
+boolean_t dsl_prop_get_hasrecvd(const char *dsname);
+int dsl_prop_set_hasrecvd(const char *dsname);
+void dsl_prop_unset_hasrecvd(const char *dsname);
 
 void dsl_prop_nvlist_add_uint64(nvlist_t *nv, zfs_prop_t prop, uint64_t value);
 void dsl_prop_nvlist_add_string(nvlist_t *nv,
diff --git a/include/sys/dsl_synctask.h b/include/sys/dsl_synctask.h
index 9126290cd..ef86fb64c 100644
--- a/include/sys/dsl_synctask.h
+++ b/include/sys/dsl_synctask.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_SYNCTASK_H
@@ -34,43 +35,26 @@ extern "C" {
 
 struct dsl_pool;
 
-typedef int (dsl_checkfunc_t)(void *, void *, dmu_tx_t *);
-typedef void (dsl_syncfunc_t)(void *, void *, dmu_tx_t *);
+typedef int (dsl_checkfunc_t)(void *, dmu_tx_t *);
+typedef void (dsl_syncfunc_t)(void *, dmu_tx_t *);
 
 typedef struct dsl_sync_task {
-	list_node_t dst_node;
+	txg_node_t dst_node;
+	struct dsl_pool *dst_pool;
+	uint64_t dst_txg;
+	int dst_space;
 	dsl_checkfunc_t *dst_checkfunc;
 	dsl_syncfunc_t *dst_syncfunc;
-	void *dst_arg1;
-	void *dst_arg2;
-	int dst_err;
+	void *dst_arg;
+	int dst_error;
+	boolean_t dst_nowaiter;
 } dsl_sync_task_t;
 
-typedef struct dsl_sync_task_group {
-	txg_node_t dstg_node;
-	list_t dstg_tasks;
-	struct dsl_pool *dstg_pool;
-	uint64_t dstg_txg;
-	int dstg_err;
-	int dstg_space;
-	boolean_t dstg_nowaiter;
-} dsl_sync_task_group_t;
-
-dsl_sync_task_group_t *dsl_sync_task_group_create(struct dsl_pool *dp);
-void dsl_sync_task_create(dsl_sync_task_group_t *dstg,
-    dsl_checkfunc_t *, dsl_syncfunc_t *,
-    void *arg1, void *arg2, int blocks_modified);
-int dsl_sync_task_group_wait(dsl_sync_task_group_t *dstg);
-void dsl_sync_task_group_nowait(dsl_sync_task_group_t *dstg, dmu_tx_t *tx);
-void dsl_sync_task_group_destroy(dsl_sync_task_group_t *dstg);
-void dsl_sync_task_group_sync(dsl_sync_task_group_t *dstg, dmu_tx_t *tx);
-
-int dsl_sync_task_do(struct dsl_pool *dp,
-    dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc,
-    void *arg1, void *arg2, int blocks_modified);
-void dsl_sync_task_do_nowait(struct dsl_pool *dp,
-    dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc,
-    void *arg1, void *arg2, int blocks_modified, dmu_tx_t *tx);
+void dsl_sync_task_sync(dsl_sync_task_t *dst, dmu_tx_t *tx);
+int dsl_sync_task(const char *pool, dsl_checkfunc_t *checkfunc,
+    dsl_syncfunc_t *syncfunc, void *arg, int blocks_modified);
+void dsl_sync_task_nowait(struct dsl_pool *dp, dsl_syncfunc_t *syncfunc,
+    void *arg, int blocks_modified, dmu_tx_t *tx);
 
 #ifdef	__cplusplus
 }
diff --git a/include/sys/dsl_userhold.h b/include/sys/dsl_userhold.h
new file mode 100644
index 000000000..56c6c8f47
--- /dev/null
+++ b/include/sys/dsl_userhold.h
@@ -0,0 +1,57 @@
+
+/*
+ * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ */
+
+#ifndef	_SYS_DSL_USERHOLD_H
+#define	_SYS_DSL_USERHOLD_H
+
+#include <sys/nvpair.h>
+#include <sys/types.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+struct dsl_pool;
+struct dsl_dataset;
+struct dmu_tx;
+
+int dsl_dataset_user_hold(nvlist_t *holds, minor_t cleanup_minor,
+    nvlist_t *errlist);
+int dsl_dataset_user_release(nvlist_t *holds, nvlist_t *errlist);
+int dsl_dataset_get_holds(const char *dsname, nvlist_t *nvl);
+void dsl_dataset_user_release_tmp(struct dsl_pool *dp, uint64_t dsobj,
+    const char *htag);
+int dsl_dataset_user_hold_check_one(struct dsl_dataset *ds, const char *htag,
+    boolean_t temphold, struct dmu_tx *tx);
+void dsl_dataset_user_hold_sync_one(struct dsl_dataset *ds, const char *htag,
+    minor_t minor, uint64_t now, struct dmu_tx *tx);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif /* _SYS_DSL_USERHOLD_H */
diff --git a/include/sys/metaslab.h b/include/sys/metaslab.h
index 99912424b..70f7af0a5 100644
--- a/include/sys/metaslab.h
+++ b/include/sys/metaslab.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.
  */
 
 #ifndef _SYS_METASLAB_H
@@ -57,6 +57,7 @@ extern int metaslab_alloc(spa_t *spa, metaslab_class_t *mc, uint64_t psize,
 extern void metaslab_free(spa_t *spa, const blkptr_t *bp, uint64_t txg,
     boolean_t now);
 extern int metaslab_claim(spa_t *spa, const blkptr_t *bp, uint64_t txg);
+extern void metaslab_check_free(spa_t *spa, const blkptr_t *bp);
 extern void metaslab_fastwrite_mark(spa_t *spa, const blkptr_t *bp);
 extern void metaslab_fastwrite_unmark(spa_t *spa, const blkptr_t *bp);
 
diff --git a/include/sys/nvpair.h b/include/sys/nvpair.h
index c502568a6..7a6787045 100644
--- a/include/sys/nvpair.h
+++ b/include/sys/nvpair.h
@@ -285,6 +285,7 @@ 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 *);
+size_t fnvlist_num_pairs(nvlist_t *);
 
 void fnvlist_add_boolean(nvlist_t *, const char *);
 void fnvlist_add_boolean_value(nvlist_t *, const char *, boolean_t);
diff --git a/include/sys/refcount.h b/include/sys/refcount.h
index 1752c64e3..e767a2389 100644
--- a/include/sys/refcount.h
+++ b/include/sys/refcount.h
@@ -50,15 +50,17 @@ typedef struct reference {
 
 typedef struct refcount {
 	kmutex_t rc_mtx;
+	boolean_t rc_tracked;
 	list_t rc_list;
 	list_t rc_removed;
 	int64_t rc_count;
 	int64_t rc_removed_count;
 } refcount_t;
 
-/* Note: refcount_t must be initialized with refcount_create() */
+/* Note: refcount_t must be initialized with refcount_create[_untracked]() */
 
 void refcount_create(refcount_t *rc);
+void refcount_create_untracked(refcount_t *rc);
 void refcount_destroy(refcount_t *rc);
 void refcount_destroy_many(refcount_t *rc, uint64_t number);
 int refcount_is_zero(refcount_t *rc);
@@ -79,6 +81,7 @@ typedef struct refcount {
 } refcount_t;
 
 #define	refcount_create(rc) ((rc)->rc_count = 0)
+#define	refcount_create_untracked(rc) ((rc)->rc_count = 0)
 #define	refcount_destroy(rc) ((rc)->rc_count = 0)
 #define	refcount_destroy_many(rc, number) ((rc)->rc_count = 0)
 #define	refcount_is_zero(rc) ((rc)->rc_count == 0)
diff --git a/include/sys/rrwlock.h b/include/sys/rrwlock.h
index 8fde3a3be..25c8a5246 100644
--- a/include/sys/rrwlock.h
+++ b/include/sys/rrwlock.h
@@ -60,6 +60,7 @@ typedef struct rrwlock {
 	refcount_t	rr_anon_rcount;
 	refcount_t	rr_linked_rcount;
 	boolean_t	rr_writer_wanted;
+	boolean_t	rr_track_all;
 } rrwlock_t;
 
 /*
@@ -67,15 +68,19 @@ typedef struct rrwlock {
  * 'tag' must be the same in a rrw_enter() as in its
  * corresponding rrw_exit().
  */
-void rrw_init(rrwlock_t *rrl);
+void rrw_init(rrwlock_t *rrl, boolean_t track_all);
 void rrw_destroy(rrwlock_t *rrl);
 void rrw_enter(rrwlock_t *rrl, krw_t rw, void *tag);
+void rrw_enter_read(rrwlock_t *rrl, void *tag);
+void rrw_enter_write(rrwlock_t *rrl);
 void rrw_exit(rrwlock_t *rrl, void *tag);
 boolean_t rrw_held(rrwlock_t *rrl, krw_t rw);
 void rrw_tsd_destroy(void *arg);
 
 #define	RRW_READ_HELD(x)	rrw_held(x, RW_READER)
 #define	RRW_WRITE_HELD(x)	rrw_held(x, RW_WRITER)
+#define	RRW_LOCK_HELD(x) \
+	(rrw_held(x, RW_WRITER) || rrw_held(x, RW_READER))
 
 #ifdef	__cplusplus
 }
diff --git a/include/sys/spa.h b/include/sys/spa.h
index 1af9137f8..401ae8343 100644
--- a/include/sys/spa.h
+++ b/include/sys/spa.h
@@ -422,7 +422,7 @@ extern int spa_get_stats(const char *pool, nvlist_t **config, char *altroot,
 extern int spa_create(const char *pool, nvlist_t *config, nvlist_t *props,
     nvlist_t *zplprops);
 extern int spa_import_rootpool(char *devpath, char *devid);
-extern int spa_import(const char *pool, nvlist_t *config, nvlist_t *props,
+extern int spa_import(char *pool, nvlist_t *config, nvlist_t *props,
     uint64_t flags);
 extern nvlist_t *spa_tryimport(nvlist_t *tryconfig);
 extern int spa_destroy(char *pool);
diff --git a/include/sys/space_map.h b/include/sys/space_map.h
index 2da80d29b..c53074a00 100644
--- a/include/sys/space_map.h
+++ b/include/sys/space_map.h
@@ -149,6 +149,8 @@ extern void space_map_add(space_map_t *sm, uint64_t start, uint64_t size);
 extern void space_map_remove(space_map_t *sm, uint64_t start, uint64_t size);
 extern boolean_t space_map_contains(space_map_t *sm,
     uint64_t start, uint64_t size);
+extern space_seg_t *space_map_find(space_map_t *sm, uint64_t start,
+    uint64_t size, avl_index_t *wherep);
 extern void space_map_swap(space_map_t **msrc, space_map_t **mdest);
 extern void space_map_vacate(space_map_t *sm,
     space_map_func_t *func, space_map_t *mdest);
diff --git a/include/sys/txg.h b/include/sys/txg.h
index f9d6dd421..b9bbba8be 100644
--- a/include/sys/txg.h
+++ b/include/sys/txg.h
@@ -45,9 +45,6 @@ extern "C" {
 /* Number of txgs worth of frees we defer adding to in-core spacemaps */
 #define	TXG_DEFER_SIZE		2
 
-#define	TXG_WAIT		1ULL
-#define	TXG_NOWAIT		2ULL
-
 typedef struct tx_cpu tx_cpu_t;
 
 typedef struct txg_handle {
@@ -125,11 +122,11 @@ extern void txg_wait_callbacks(struct dsl_pool *dp);
 extern void txg_list_create(txg_list_t *tl, size_t offset);
 extern void txg_list_destroy(txg_list_t *tl);
 extern boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg);
-extern int txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
-extern int txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg);
+extern boolean_t txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
+extern boolean_t txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg);
 extern void *txg_list_remove(txg_list_t *tl, uint64_t txg);
 extern void *txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg);
-extern int txg_list_member(txg_list_t *tl, void *p, uint64_t txg);
+extern boolean_t txg_list_member(txg_list_t *tl, void *p, uint64_t txg);
 extern void *txg_list_head(txg_list_t *tl, uint64_t txg);
 extern void *txg_list_next(txg_list_t *tl, void *p, uint64_t txg);
 
diff --git a/include/sys/zfeature.h b/include/sys/zfeature.h
index 481e85b1b..1a081e422 100644
--- a/include/sys/zfeature.h
+++ b/include/sys/zfeature.h
@@ -26,7 +26,6 @@
 #ifndef _SYS_ZFEATURE_H
 #define	_SYS_ZFEATURE_H
 
-#include <sys/dmu.h>
 #include <sys/nvpair.h>
 #include "zfeature_common.h"
 
@@ -34,14 +33,18 @@
 extern "C" {
 #endif
 
-extern boolean_t feature_is_supported(objset_t *os, uint64_t obj,
+struct spa;
+struct dmu_tx;
+struct objset;
+
+extern boolean_t feature_is_supported(struct objset *os, uint64_t obj,
     uint64_t desc_obj, nvlist_t *unsup_feat, nvlist_t *enabled_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 void spa_feature_create_zap_objects(struct spa *, struct dmu_tx *);
+extern void spa_feature_enable(struct spa *, zfeature_info_t *,
+    struct dmu_tx *);
+extern void spa_feature_incr(struct spa *, zfeature_info_t *, struct dmu_tx *);
+extern void spa_feature_decr(struct spa *, zfeature_info_t *, struct dmu_tx *);
 extern boolean_t spa_feature_is_enabled(struct spa *, zfeature_info_t *);
 extern boolean_t spa_feature_is_active(struct spa *, zfeature_info_t *);
 
diff --git a/include/sys/zfs_context.h b/include/sys/zfs_context.h
index 599b97a9b..a126c058e 100644
--- a/include/sys/zfs_context.h
+++ b/include/sys/zfs_context.h
@@ -209,8 +209,6 @@ typedef struct kthread {
 	void *		t_arg;
 } kthread_t;
 
-#define	tsd_get(key)			pthread_getspecific(key)
-#define	tsd_set(key, val)		pthread_setspecific(key, val)
 #define	curthread			zk_thread_current()
 #define	thread_exit			zk_thread_exit
 #define	thread_create(stk, stksize, func, arg, len, pp, state, pri)	\
@@ -284,6 +282,12 @@ typedef int krw_t;
 #define	RW_WRITE_HELD(x)	((x)->rw_wr_owner == curthread)
 #define	RW_LOCK_HELD(x)		(RW_READ_HELD(x) || RW_WRITE_HELD(x))
 
+#undef RW_LOCK_HELD
+#define	RW_LOCK_HELD(x)		(RW_READ_HELD(x) || RW_WRITE_HELD(x))
+
+#undef RW_LOCK_HELD
+#define	RW_LOCK_HELD(x)		(RW_READ_HELD(x) || RW_WRITE_HELD(x))
+
 extern void rw_init(krwlock_t *rwlp, char *name, int type, void *arg);
 extern void rw_destroy(krwlock_t *rwlp);
 extern void rw_enter(krwlock_t *rwlp, krw_t rw);
@@ -321,6 +325,22 @@ extern void cv_broadcast(kcondvar_t *cv);
 #define cv_wait_io(cv, mp)			cv_wait(cv, mp)
 
 /*
+ * Thread-specific data
+ */
+#define	tsd_get(k) pthread_getspecific(k)
+#define	tsd_set(k, v) pthread_setspecific(k, v)
+#define	tsd_create(kp, d) pthread_key_create(kp, d)
+#define	tsd_destroy(kp) /* nothing */
+
+/*
+ * Thread-specific data
+ */
+#define	tsd_get(k) pthread_getspecific(k)
+#define	tsd_set(k, v) pthread_setspecific(k, v)
+#define	tsd_create(kp, d) pthread_key_create(kp, d)
+#define	tsd_destroy(kp) /* nothing */
+
+/*
  * kstat creation, installation and deletion
  */
 extern kstat_t *kstat_create(char *, int,
@@ -592,7 +612,7 @@ typedef struct callb_cpr {
 
 extern char *kmem_vasprintf(const char *fmt, va_list adx);
 extern char *kmem_asprintf(const char *fmt, ...);
-#define	strfree(str) kmem_free((str), strlen(str)+1)
+#define	strfree(str) kmem_free((str), strlen(str) + 1)
 
 /*
  * Hostname information
diff --git a/include/sys/zfs_debug.h b/include/sys/zfs_debug.h
index 591d0df8f..7632d7420 100644
--- a/include/sys/zfs_debug.h
+++ b/include/sys/zfs_debug.h
@@ -43,11 +43,13 @@
 extern int zfs_flags;
 extern int zfs_recover;
 
-#define	ZFS_DEBUG_DPRINTF	0x0001
-#define	ZFS_DEBUG_DBUF_VERIFY	0x0002
-#define	ZFS_DEBUG_DNODE_VERIFY	0x0004
-#define	ZFS_DEBUG_SNAPNAMES	0x0008
-#define	ZFS_DEBUG_MODIFY	0x0010
+#define	ZFS_DEBUG_DPRINTF	(1<<0)
+#define	ZFS_DEBUG_DBUF_VERIFY	(1<<1)
+#define	ZFS_DEBUG_DNODE_VERIFY	(1<<2)
+#define	ZFS_DEBUG_SNAPNAMES	(1<<3)
+#define	ZFS_DEBUG_MODIFY	(1<<4)
+#define	ZFS_DEBUG_SPA		(1<<5)
+#define	ZFS_DEBUG_ZIO_FREE	(1<<6)
 
 /*
  * Always log zfs debug messages to the spl debug subsystem as SS_USER1.
diff --git a/include/sys/zfs_ioctl.h b/include/sys/zfs_ioctl.h
index 21bfe2b8f..8838322a9 100644
--- a/include/sys/zfs_ioctl.h
+++ b/include/sys/zfs_ioctl.h
@@ -302,7 +302,6 @@ typedef struct zfs_cmd {
 	uint64_t	zc_history;		/* really (char *) */
 	char		zc_value[MAXPATHLEN * 2];
 	char		zc_string[MAXNAMELEN];
-	char		zc_top_ds[MAXPATHLEN];
 	uint64_t	zc_guid;
 	uint64_t	zc_nvlist_conf;		/* really (char *) */
 	uint64_t	zc_nvlist_conf_size;
@@ -352,7 +351,8 @@ extern int zfs_secpolicy_snapshot_perms(const char *name, cred_t *cr);
 extern int zfs_secpolicy_rename_perms(const char *from,
     const char *to, cred_t *cr);
 extern int zfs_secpolicy_destroy_perms(const char *name, cred_t *cr);
-extern int zfs_unmount_snap(const char *, void *);
+extern void zfs_unmount_snap(const char *);
+extern void zfs_destroy_unmount_origin(const char *);
 
 enum zfsdev_state_type {
 	ZST_ONEXIT,
diff --git a/include/sys/zfs_znode.h b/include/sys/zfs_znode.h
index bdddcc366..aa9d9d288 100644
--- a/include/sys/zfs_znode.h
+++ b/include/sys/zfs_znode.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_FS_ZFS_ZNODE_H
@@ -254,7 +255,7 @@ typedef struct znode {
  */
 #define	ZFS_ENTER(zsb) \
 	{ \
-		rrw_enter(&(zsb)->z_teardown_lock, RW_READER, FTAG); \
+		rrw_enter_read(&(zsb)->z_teardown_lock, FTAG); \
 		if ((zsb)->z_unmounted) { \
 			ZFS_EXIT(zsb); \
 			return (EIO); \
diff --git a/include/sys/zil.h b/include/sys/zil.h
index 589e28f83..f3e00101b 100644
--- a/include/sys/zil.h
+++ b/include/sys/zil.h
@@ -470,8 +470,8 @@ extern int	zil_check_log_chain(const char *osname, void *txarg);
 extern void	zil_sync(zilog_t *zilog, dmu_tx_t *tx);
 extern void	zil_clean(zilog_t *zilog, uint64_t synced_txg);
 
-extern int	zil_suspend(zilog_t *zilog);
-extern void	zil_resume(zilog_t *zilog);
+extern int	zil_suspend(const char *osname, void **cookiep);
+extern void	zil_resume(void *cookie);
 
 extern void	zil_add_block(zilog_t *zilog, const blkptr_t *bp);
 extern int	zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp);
diff --git a/include/sys/zvol.h b/include/sys/zvol.h
index c05f81a5f..640538c2c 100644
--- a/include/sys/zvol.h
+++ b/include/sys/zvol.h
@@ -39,7 +39,7 @@ extern int zvol_get_stats(objset_t *os, nvlist_t *nv);
 extern boolean_t zvol_is_zvol(const char *);
 extern void zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx);
 extern int zvol_create_minor(const char *);
-extern int zvol_create_minors(const char *);
+extern int zvol_create_minors(char *);
 extern int zvol_remove_minor(const char *);
 extern void zvol_remove_minors(const char *);
 extern int zvol_set_volsize(const char *, uint64_t);