diff --git a/include/sys/zfs_context.h b/include/sys/zfs_context.h
index 39dca9939..17d3ed20c 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_MUTEX_H
 #define	_SYS_RWLOCK_H
 #define	_SYS_CONDVAR_H
 #define	_SYS_VNODE_H
@@ -122,6 +121,7 @@ extern "C" {
 #include <sys/utsname.h>
 #include <sys/trace_zfs.h>
 
+#include <sys/mutex.h>
 #include <sys/zfs_delay.h>
 
 #include <sys/zfs_context_os.h>
@@ -253,29 +253,6 @@ extern kthread_t *zk_thread_create(const char *name, void (*func)(void *),
 #define	kpreempt_disable()	((void)0)
 #define	kpreempt_enable()	((void)0)
 
-/*
- * Mutexes
- */
-typedef struct kmutex {
-	pthread_mutex_t		m_lock;
-	pthread_t		m_owner;
-} kmutex_t;
-
-#define	MUTEX_DEFAULT		0
-#define	MUTEX_NOLOCKDEP		MUTEX_DEFAULT
-#define	MUTEX_HELD(mp)		pthread_equal((mp)->m_owner, pthread_self())
-#define	MUTEX_NOT_HELD(mp)	!MUTEX_HELD(mp)
-
-extern void mutex_init(kmutex_t *mp, char *name, int type, void *cookie);
-extern void mutex_destroy(kmutex_t *mp);
-extern void mutex_enter(kmutex_t *mp);
-extern int mutex_enter_check_return(kmutex_t *mp);
-extern void mutex_exit(kmutex_t *mp);
-extern int mutex_tryenter(kmutex_t *mp);
-
-#define	NESTED_SINGLE 1
-#define	mutex_enter_nested(mp, class) mutex_enter(mp)
-#define	mutex_enter_interruptible(mp) mutex_enter_check_return(mp)
 /*
  * RW locks
  */
diff --git a/lib/libspl/include/Makefile.am b/lib/libspl/include/Makefile.am
index 98184340e..d4649c2d5 100644
--- a/lib/libspl/include/Makefile.am
+++ b/lib/libspl/include/Makefile.am
@@ -44,6 +44,7 @@ libspl_sys_HEADERS = \
 	%D%/sys/mhd.h \
 	%D%/sys/mkdev.h \
 	%D%/sys/mod.h \
+	%D%/sys/mutex.h \
 	%D%/sys/policy.h \
 	%D%/sys/poll.h \
 	%D%/sys/priv.h \
diff --git a/lib/libspl/include/sys/mutex.h b/lib/libspl/include/sys/mutex.h
new file mode 100644
index 000000000..1da0e632d
--- /dev/null
+++ b/lib/libspl/include/sys/mutex.h
@@ -0,0 +1,58 @@
+// 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_MUTEX_H
+#define	_SYS_MUTEX_H
+
+#include <pthread.h>
+
+/*
+ * Mutexes
+ */
+typedef struct kmutex {
+	pthread_mutex_t		m_lock;
+	pthread_t		m_owner;
+} kmutex_t;
+
+#define	MUTEX_DEFAULT		0
+#define	MUTEX_NOLOCKDEP		MUTEX_DEFAULT
+#define	MUTEX_HELD(mp)		pthread_equal((mp)->m_owner, pthread_self())
+#define	MUTEX_NOT_HELD(mp)	!MUTEX_HELD(mp)
+
+extern void mutex_init(kmutex_t *mp, char *name, int type, void *cookie);
+extern void mutex_destroy(kmutex_t *mp);
+extern void mutex_enter(kmutex_t *mp);
+extern int mutex_enter_check_return(kmutex_t *mp);
+extern void mutex_exit(kmutex_t *mp);
+extern int mutex_tryenter(kmutex_t *mp);
+
+#define	NESTED_SINGLE 1
+#define	mutex_enter_nested(mp, class) mutex_enter(mp)
+#define	mutex_enter_interruptible(mp) mutex_enter_check_return(mp)
+
+#endif /* _SYS_MUTEX_H */