diff --git a/include/sys/zfs_context.h b/include/sys/zfs_context.h
index 17d3ed20c..d96113f26 100644
--- a/include/sys/zfs_context.h
+++ b/include/sys/zfs_context.h
@@ -77,7 +77,6 @@ extern "C" {
 #include <sys/zfs_context_os.h>
 #else /* _KERNEL || _STANDALONE */
 
-#define	_SYS_RWLOCK_H
 #define	_SYS_CONDVAR_H
 #define	_SYS_VNODE_H
 #define	_SYS_VFS_H
@@ -122,6 +121,7 @@ extern "C" {
 #include <sys/trace_zfs.h>
 
 #include <sys/mutex.h>
+#include <sys/rwlock.h>
 #include <sys/zfs_delay.h>
 
 #include <sys/zfs_context_os.h>
@@ -253,34 +253,6 @@ extern kthread_t *zk_thread_create(const char *name, void (*func)(void *),
 #define	kpreempt_disable()	((void)0)
 #define	kpreempt_enable()	((void)0)
 
-/*
- * RW locks
- */
-typedef struct krwlock {
-	pthread_rwlock_t	rw_lock;
-	pthread_t		rw_owner;
-	uint_t			rw_readers;
-} krwlock_t;
-
-typedef int krw_t;
-
-#define	RW_READER		0
-#define	RW_WRITER		1
-#define	RW_DEFAULT		RW_READER
-#define	RW_NOLOCKDEP		RW_READER
-
-#define	RW_READ_HELD(rw)	((rw)->rw_readers > 0)
-#define	RW_WRITE_HELD(rw)	pthread_equal((rw)->rw_owner, pthread_self())
-#define	RW_LOCK_HELD(rw)	(RW_READ_HELD(rw) || RW_WRITE_HELD(rw))
-
-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);
-extern int rw_tryenter(krwlock_t *rwlp, krw_t rw);
-extern int rw_tryupgrade(krwlock_t *rwlp);
-extern void rw_exit(krwlock_t *rwlp);
-#define	rw_downgrade(rwlp) do { } while (0)
-
 /*
  * Credentials
  */
diff --git a/lib/libspl/include/Makefile.am b/lib/libspl/include/Makefile.am
index d4649c2d5..f490bb9f7 100644
--- a/lib/libspl/include/Makefile.am
+++ b/lib/libspl/include/Makefile.am
@@ -49,6 +49,7 @@ libspl_sys_HEADERS = \
 	%D%/sys/poll.h \
 	%D%/sys/priv.h \
 	%D%/sys/processor.h \
+	%D%/sys/rwlock.h \
 	%D%/sys/simd.h \
 	%D%/sys/stack.h \
 	%D%/sys/stdtypes.h \
diff --git a/lib/libspl/include/sys/rwlock.h b/lib/libspl/include/sys/rwlock.h
new file mode 100644
index 000000000..9f82f270d
--- /dev/null
+++ b/lib/libspl/include/sys/rwlock.h
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: CDDL-1.0
+/*
+ * 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 https://opensource.org/licenses/CDDL-1.0.
+ * 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 2011 Nexenta Systems, Inc.  All rights reserved.
+ * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ */
+
+#ifndef _SYS_RWLOCK_H
+#define	_SYS_RWLOCK_H
+
+#include <pthread.h>
+
+/*
+ * RW locks
+ */
+typedef struct krwlock {
+	pthread_rwlock_t	rw_lock;
+	pthread_t		rw_owner;
+	uint_t			rw_readers;
+} krwlock_t;
+
+typedef int krw_t;
+
+#define	RW_READER		0
+#define	RW_WRITER		1
+#define	RW_DEFAULT		RW_READER
+#define	RW_NOLOCKDEP		RW_READER
+
+#define	RW_READ_HELD(rw)	((rw)->rw_readers > 0)
+#define	RW_WRITE_HELD(rw)	pthread_equal((rw)->rw_owner, pthread_self())
+#define	RW_LOCK_HELD(rw)	(RW_READ_HELD(rw) || RW_WRITE_HELD(rw))
+
+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);
+extern int rw_tryenter(krwlock_t *rwlp, krw_t rw);
+extern int rw_tryupgrade(krwlock_t *rwlp);
+extern void rw_exit(krwlock_t *rwlp);
+#define	rw_downgrade(rwlp) do { } while (0)
+
+#endif /* _SYS_RWLOCK_H */