diff --git a/config/user-ioctl.m4 b/config/user-ioctl.m4
deleted file mode 100644
index 53fb118fc..000000000
--- a/config/user-ioctl.m4
+++ /dev/null
@@ -1,35 +0,0 @@
-dnl #
-dnl # Check for ioctl()
-dnl #
-AC_DEFUN([ZFS_AC_CONFIG_USER_IOCTL], [
-	AC_MSG_CHECKING(for ioctl())
-	AC_EGREP_HEADER(ioctl, unistd.h, is_unistd=yes, is_unistd=no)
-	AC_EGREP_HEADER(ioctl, sys/ioctl.h, is_sys_ioctl=yes, is_sys_ioctl=no)
-	AC_EGREP_HEADER(ioctl, stropts.h, is_stropts=yes, is_stropts=no)
-
-	if test $is_unistd = yes; then
-		result=unistd.h
-		AC_DEFINE([HAVE_IOCTL_IN_UNISTD_H], 1,
-		[Define to 1 if ioctl() defined in <unistd.h>])
-	else
-
-		if test $is_sys_ioctl = yes; then
-			result=sys/ioctl.h
-			AC_DEFINE([HAVE_IOCTL_IN_SYS_IOCTL_H], 1,
-			[Define to 1 if ioctl() defined in <sys/ioctl.h>])
-		elif test $is_stropts = yes; then
-			AC_DEFINE([HAVE_IOCTL_IN_STROPTS_H], 1,
-			result=stropts.h
-			[Define to 1 if ioctl() defined in <stropts.h>])
-		else
-			result=no
-		fi
-	fi
-
-	if test $result = no; then
-                AC_MSG_RESULT([no])
-                AC_MSG_ERROR([*** Cannot locate ioctl() definition])
-	else
-		AC_MSG_RESULT(yes)
-	fi
-])
diff --git a/config/user.m4 b/config/user.m4
index 38024370b..d7ac3f24f 100644
--- a/config/user.m4
+++ b/config/user.m4
@@ -7,7 +7,6 @@ AC_DEFUN([ZFS_AC_CONFIG_USER], [
 	ZFS_AC_CONFIG_USER_SYSVINIT
 	ZFS_AC_CONFIG_USER_DRACUT
 	ZFS_AC_CONFIG_USER_ARCH
-	ZFS_AC_CONFIG_USER_IOCTL
 	ZFS_AC_CONFIG_USER_ZLIB
 	ZFS_AC_CONFIG_USER_LIBUUID
 	ZFS_AC_CONFIG_USER_LIBBLKID
diff --git a/lib/libspl/include/unistd.h b/lib/libspl/include/unistd.h
index 53851f4ab..0246991b4 100644
--- a/lib/libspl/include/unistd.h
+++ b/lib/libspl/include/unistd.h
@@ -29,15 +29,7 @@
 #ifndef _LIBSPL_UNISTD_H
 #define	_LIBSPL_UNISTD_H
 
-#if !defined(HAVE_IOCTL_IN_UNISTD_H)
-#if defined(HAVE_IOCTL_IN_SYS_IOCTL_H)
 #include <sys/ioctl.h>
-#elif defined(HAVE_IOCTL_IN_STROPTS_H)
-#include <stropts.h>
-#else /* HAVE_IOCTL_IN_STROPTS_H */
-#error "System call ioctl() unavailable"
-#endif /* HAVE_IOCTL_IN_SYS_IOCTL_H */
-#endif /* !HAVE_IOCTL_IN_UNISTD_H */
 
 #if !defined(HAVE_ISSETUGID)
 #include <sys/types.h>