diff --git a/sys/sys/_acl_type.h b/sys/sys/_acl_type.h
new file mode 100644
--- /dev/null
+++ b/sys/sys/_acl_type.h
@@ -0,0 +1,43 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 1999-2001 Robert N. M. Watson
+ * Copyright (c) 2008 Edward Tomasz Napierała <trasz@FreeBSD.org>
+ * All rights reserved.
+ *
+ * This software was developed by Robert Watson for the TrustedBSD Project.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+/*
+ * Developed by the TrustedBSD Project.
+ * Support for POSIX.1e and NFSv4 access control lists.
+ */
+
+#ifndef _SYS__ACL_TYPE_H_
+#define	_SYS__ACL_TYPE_H_
+
+#include <sys/_types.h>
+
+typedef __int32_t	acl_type_t;
+
+#endif /* !_SYS__ACL_TYPE_H_ */
diff --git a/sys/sys/acl.h b/sys/sys/acl.h
--- a/sys/sys/acl.h
+++ b/sys/sys/acl.h
@@ -37,6 +37,7 @@
 #define	_SYS_ACL_H_
 
 #include <sys/param.h>
+#include <sys/_acl_type.h>
 #include <sys/queue.h>
 #include <vm/uma.h>
 
@@ -48,7 +49,6 @@
 typedef uint32_t	acl_perm_t;
 typedef uint16_t	acl_entry_type_t;
 typedef uint16_t	acl_flag_t;
-typedef int		acl_type_t;
 typedef int		*acl_permset_t;
 typedef uint16_t	*acl_flagset_t;