diff --git a/tests/sys/kern/sendfile_helper.c b/tests/sys/kern/sendfile_helper.c
index 6a3b4a1ac880..703b04fdea6c 100644
--- a/tests/sys/kern/sendfile_helper.c
+++ b/tests/sys/kern/sendfile_helper.c
@@ -1,156 +1,177 @@
 /*-
  * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 2020 Netflix, Inc.
  *
  * 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.
  */
 
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/sysctl.h>
 #include <sys/uio.h>
 
 #include <netinet/in.h>
 
 #include <err.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <pthread.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 
 static char buf[1024*1024];
 ssize_t readlen;
 static volatile bool read_done = false;
 
 static int
 tcp_socketpair(int *sv)
 {
 	struct sockaddr_in sin = {
 		.sin_len = sizeof(struct sockaddr_in),
 		.sin_family = AF_INET,
 		.sin_addr.s_addr = htonl(INADDR_LOOPBACK),
 	};
 	int flags;
 	int ls;
 
 	ls = socket(PF_INET, SOCK_STREAM, 0);
 	if (ls < 0)
 		err(1, "socket ls");
 
 	if (setsockopt(ls, SOL_SOCKET, SO_REUSEADDR, &(socklen_t){1},
 	    sizeof(int)) < 0)
 		err(1, "SO_REUSEADDR");
 
 	if (bind(ls, (struct sockaddr *)&sin, sizeof(sin)) < 0)
 		err(1, "bind ls");
 
 	if (getsockname(ls, (struct sockaddr *)&sin,
 	    &(socklen_t){ sizeof(sin) }) < 0)
 		err(1, "getsockname");
 
 	if (listen(ls, 5) < 0)
 		err(1, "listen ls");
 
 	sv[0] = socket(PF_INET, SOCK_STREAM, 0);
 	if (sv[0] < 0)
 		err(1, "socket cs");
 
 	flags = fcntl(sv[0], F_GETFL);
 	flags |= O_NONBLOCK;
 	if (fcntl(sv[0], F_SETFL, flags) == -1)
 		err(1, "fcntl +O_NONBLOCK");
 
 	if (connect(sv[0], (void *)&sin, sizeof(sin)) != -1 ||
 	    errno != EINPROGRESS)
 		err(1, "connect cs");
 
 	sv[1] = accept(ls, NULL, 0);
 	if (sv[1] < 0)
 		err(1, "accept ls");
 
 	flags &= ~O_NONBLOCK;
 	if (fcntl(sv[0], F_SETFL, flags) == -1)
 		err(1, "fcntl -O_NONBLOCK");
 
 	close(ls);
 
 	return (0);
 }
 
 static void *
 receiver(void *arg)
 {
 	int s = *(int *)arg;
 	ssize_t rv;
 
 	do {
 		rv = read(s, buf, sizeof(buf));
 		if (rv == -1)
 			err(2, "read receiver");
 		if (rv == 0)
 			break;
 		readlen -= rv;
 	} while (readlen != 0);
 
 	read_done = true;
 
 	return NULL;
 }
 
+static void
+usage(void)
+{
+	errx(1, "usage: %s [-u] <file> <start> <len> <flags>", getprogname());
+}
+
 int
 main(int argc, char **argv)
 {
 	pthread_t pt;
 	off_t start;
-	int fd, ss[2], flags, error;
+	int ch, fd, ss[2], flags, error;
+	bool pf_unix = false;
+
+	while ((ch = getopt(argc, argv, "u")) != -1)
+		switch (ch) {
+		case 'u':
+			pf_unix = true;
+			break;
+		default:
+			usage();
+		}
+	argc -= optind;
+	argv += optind;
 
-	if (argc != 5)
-		errx(1, "usage: %s <file> <start> <len> <flags>",
-		    getprogname());
+	if (argc != 4)
+		usage();
 
-	start = strtoull(argv[2], NULL, 0);
-	readlen = strtoull(argv[3], NULL, 0);
-	flags = strtoul(argv[4], NULL, 0);
+	start = strtoull(argv[1], NULL, 0);
+	readlen = strtoull(argv[2], NULL, 0);
+	flags = strtoul(argv[3], NULL, 0);
 
-	fd = open(argv[1], O_RDONLY);
+	fd = open(argv[0], O_RDONLY);
 	if (fd < 0)
 		err(1, "open");
 
-	tcp_socketpair(ss);
+	if (pf_unix) {
+		if (socketpair(PF_LOCAL, SOCK_STREAM, 0, ss) != 0)
+			err(1, "socketpair");
+	} else
+		tcp_socketpair(ss);
 
 	error = pthread_create(&pt, NULL, receiver, &ss[1]);
 	if (error)
 		errc(1, error, "pthread_create");
 
 	if (sendfile(fd, ss[0], start, readlen, NULL, NULL, flags) < 0)
 		err(3, "sendfile");
 
 	while (!read_done)
 		usleep(1000);
 
 	exit(0);
 }
diff --git a/tests/sys/kern/sendfile_test.sh b/tests/sys/kern/sendfile_test.sh
index 03d87292f3a3..7e549eec610a 100755
--- a/tests/sys/kern/sendfile_test.sh
+++ b/tests/sys/kern/sendfile_test.sh
@@ -1,168 +1,192 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2020 Netflix, Inc.
 #
 # 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.
 #
 
 #
 # These tests exercise a few basic cases for the sendfile() syscall:
 # - successful operation.
 # - sendfile() starts an async disk read but that async I/O fails.
 # - sendfile() fails to read an indirect block and thus cannot
 #   even start an async I/O.
 #
 # In all cases we request some read ahead in addition to
 # the data to be sent to the socket.
 #
 
 MD_DEVS="md.devs"
 MNT=mnt
 FILE=$MNT/file
 HELPER="$(atf_get_srcdir)/sendfile_helper"
 BSIZE=4096
 
 atf_test_case io_success cleanup
 io_success_head()
 {
 	atf_set "descr" "sendfile where all disk I/O succeeds"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 io_success_body()
 {
 	if [ "$(atf_config_get qemu false)" = "true" ]; then
 	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
 	fi
 
 	alloc_md md
 	common_body_setup $md
 
 	atf_check $HELPER $FILE 0 0x10000 0x10000
 }
 io_success_cleanup()
 {
 	common_cleanup
 }
 
 atf_test_case io_fail_sync cleanup
 io_fail_sync_head()
 {
 	atf_set "descr" "sendfile where we fail to start async I/O"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 io_fail_sync_body()
 {
 	if [ "$(atf_config_get qemu false)" = "true" ]; then
 	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
 	fi
 
 	alloc_md md
 	common_body_setup $md
 
 	atf_check gnop configure -r 100 -e 5 ${md}.nop
 	atf_check -s exit:3 -e ignore $HELPER $FILE $((12 * $BSIZE)) $BSIZE 0x10000
 }
 io_fail_sync_cleanup()
 {
 	common_cleanup
 }
 
 atf_test_case io_fail_async cleanup
 io_fail_async_head()
 {
 	atf_set "descr" "sendfile where an async I/O fails"
 	atf_set "require.user" "root"
 	atf_set "timeout" 15
 }
 io_fail_async_body()
 {
 	if [ "$(atf_config_get qemu false)" = "true" ]; then
 	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
 	fi
 
 	alloc_md md
 	common_body_setup $md
 
 	atf_check gnop configure -r 100 -e 5 ${md}.nop
 	atf_check -s exit:2 -e ignore $HELPER $FILE 0 $BSIZE 0x10000
 }
 io_fail_async_cleanup()
 {
 	common_cleanup
 }
 
+atf_test_case unix_success cleanup
+unix_success_head()
+{
+	atf_set "descr" "sendfile via unix(4) where all disk I/O succeeds"
+	atf_set "require.user" "root"
+	atf_set "timeout" 15
+}
+unix_success_body()
+{
+	if [ "$(atf_config_get qemu false)" = "true" ]; then
+	    atf_skip "Sendfile(4) unimplemented. https://github.com/qemu-bsd-user/qemu-bsd-user/issues/25"
+	fi
+
+	alloc_md md
+	common_body_setup $md
+
+	atf_check $HELPER -u $FILE 0 0x10000 0x10000
+}
+unix_success_cleanup()
+{
+	common_cleanup
+}
+
 
 atf_init_test_cases()
 {
 	atf_add_test_case io_success
 	atf_add_test_case io_fail_sync
 	atf_add_test_case io_fail_async
+	atf_add_test_case unix_success
 }
 
 alloc_md()
 {
 	local _md
 
 	[ -c /dev/mdctl ] || atf_skip "no /dev/mdctl to create md devices"
 	_md=$(mdconfig -a -t swap -s 256M) || atf_fail "mdconfig -a failed"
 	echo ${_md} >> $MD_DEVS
 	eval "${1}='${_md}'"
 }
 
 common_body_setup()
 {
 	us=$1
 
 	atf_check mkdir $MNT
 	atf_check -o ignore -e ignore newfs -b $BSIZE -U -j /dev/${us}
 	atf_check mount /dev/${us} $MNT
 	atf_check -e ignore dd if=/dev/zero of=$FILE bs=1m count=1
 	atf_check umount $MNT
 
 	load_gnop
 	atf_check gnop create /dev/${us}
 	atf_check mount /dev/${us}.nop $MNT
 	atf_check -o ignore ls -l $MNT/file
 }
 
 common_cleanup()
 {
 	umount -f $MNT
 	if [ -f "$MD_DEVS" ]; then
 		while read test_md; do
 			gnop destroy -f ${test_md}.nop 2>/dev/null
 			mdconfig -d -u $test_md 2>/dev/null
 		done < $MD_DEVS
 		rm $MD_DEVS
 	fi
 
 	true
 }
 
 load_gnop()
 {
 	if ! kldstat -q -m g_nop; then
 		geom nop load || atf_skip "could not load module for geom nop"
 	fi
 }