1 files changed, 118 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/setup_loopback.sh b/tools/testing/selftests/net/setup_loopback.sh
new file mode 100755
index 000000000000..e57bbfbc5208
--- /dev/null
+++ b/tools/testing/selftests/net/setup_loopback.sh
@@ -0,0 +1,118 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+readonly FLUSH_PATH="/sys/class/net/${dev}/gro_flush_timeout"
+readonly IRQ_PATH="/sys/class/net/${dev}/napi_defer_hard_irqs"
+readonly FLUSH_TIMEOUT="$(< ${FLUSH_PATH})"
+readonly HARD_IRQS="$(< ${IRQ_PATH})"
+
+netdev_check_for_carrier() {
+	local -r dev="$1"
+
+	for i in {1..5}; do
+		carrier="$(cat /sys/class/net/${dev}/carrier)"
+		if [[ "${carrier}" -ne 1 ]] ; then
+			echo "carrier not ready yet..." >&2
+			sleep 1
+		else
+			echo "carrier ready" >&2
+			break
+		fi
+	done
+	echo "${carrier}"
+}
+
+# Assumes that there is no existing ipvlan device on the physical device
+setup_loopback_environment() {
+	local dev="$1"
+
+	# Fail hard if cannot turn on loopback mode for current NIC
+	ethtool -K "${dev}" loopback on || exit 1
+	sleep 1
+
+	# Check for the carrier
+	carrier=$(netdev_check_for_carrier ${dev})
+	if [[ "${carrier}" -ne 1 ]] ; then
+		echo "setup_loopback_environment failed"
+		exit 1
+	fi
+}
+
+setup_macvlan_ns(){
+	local -r link_dev="$1"
+	local -r ns_name="$2"
+	local -r ns_dev="$3"
+	local -r ns_mac="$4"
+	local -r addr="$5"
+
+	ip link add link "${link_dev}" dev "${ns_dev}" \
+		address "${ns_mac}" type macvlan
+	exit_code=$?
+	if [[ "${exit_code}" -ne 0 ]]; then
+		echo "setup_macvlan_ns failed"
+		exit $exit_code
+	fi
+
+	[[ -e /var/run/netns/"${ns_name}" ]] || ip netns add "${ns_name}"
+	ip link set dev "${ns_dev}" netns "${ns_name}"
+	ip -netns "${ns_name}" link set dev "${ns_dev}" up
+	if [[ -n "${addr}" ]]; then
+		ip -netns "${ns_name}" addr add dev "${ns_dev}" "${addr}"
+	fi
+
+	sleep 1
+}
+
+cleanup_macvlan_ns(){
+	while (( $# >= 2 )); do
+		ns_name="$1"
+		ns_dev="$2"
+		ip -netns "${ns_name}" link del dev "${ns_dev}"
+		ip netns del "${ns_name}"
+		shift 2
+	done
+}
+
+cleanup_loopback(){
+	local -r dev="$1"
+
+	ethtool -K "${dev}" loopback off
+	sleep 1
+
+	# Check for the carrier
+	carrier=$(netdev_check_for_carrier ${dev})
+	if [[ "${carrier}" -ne 1 ]] ; then
+		echo "setup_loopback_environment failed"
+		exit 1
+	fi
+}
+
+setup_interrupt() {
+	# Use timer on  host to trigger the network stack
+	# Also disable device interrupt to not depend on NIC interrupt
+	# Reduce test flakiness caused by unexpected interrupts
+	echo 100000 >"${FLUSH_PATH}"
+	echo 50 >"${IRQ_PATH}"
+}
+
+setup_ns() {
+	# Set up server_ns namespace and client_ns namespace
+	setup_macvlan_ns "${dev}" server_ns server "${SERVER_MAC}"
+	setup_macvlan_ns "${dev}" client_ns client "${CLIENT_MAC}"
+}
+
+cleanup_ns() {
+	cleanup_macvlan_ns server_ns server client_ns client
+}
+
+setup() {
+	setup_loopback_environment "${dev}"
+	setup_interrupt
+}
+
+cleanup() {
+	cleanup_loopback "${dev}"
+
+	echo "${FLUSH_TIMEOUT}" >"${FLUSH_PATH}"
+	echo "${HARD_IRQS}" >"${IRQ_PATH}"
+}