selftests: devlink_trap: Add test cases for devlink-trap

Add test cases for devlink-trap on top of the netdevsim implementation.

The tests focus on the devlink-trap core infrastructure and user space
API. They test both good and bad flows and also dismantle of the netdev
and devlink device used to report trapped packets.

This allows device drivers to focus their tests on device-specific
functionality.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# This test is for checking devlink-trap functionality. It makes use of
+# netdevsim which implements the required callbacks.
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+ALL_TESTS="
+	init_test
+	trap_action_test
+	trap_metadata_test
+	bad_trap_test
+	bad_trap_action_test
+	trap_stats_test
+	trap_group_action_test
+	bad_trap_group_test
+	trap_group_stats_test
+	port_del_test
+	dev_del_test
+"
+NETDEVSIM_PATH=/sys/bus/netdevsim/
+DEV_ADDR=1337
+DEV=netdevsim${DEV_ADDR}
+DEVLINK_DEV=netdevsim/${DEV}
+SLEEP_TIME=1
+NETDEV=""
+NUM_NETIFS=0
+source $lib_dir/lib.sh
+source $lib_dir/devlink_lib.sh
+
+require_command udevadm
+
+modprobe netdevsim &> /dev/null
+if [ ! -d "$NETDEVSIM_PATH" ]; then
+	echo "SKIP: No netdevsim support"
+	exit 1
+fi
+
+if [ -d "${NETDEVSIM_PATH}/devices/netdevsim${DEV_ADDR}" ]; then
+	echo "SKIP: Device netdevsim${DEV_ADDR} already exists"
+	exit 1
+fi
+
+init_test()
+{
+	RET=0
+
+	test $(devlink_traps_num_get) -ne 0
+	check_err $? "No traps were registered"
+
+	log_test "Initialization"
+}
+
+trap_action_test()
+{
+	local orig_action
+	local trap_name
+	local action
+
+	RET=0
+
+	for trap_name in $(devlink_traps_get); do
+		# The action of non-drop traps cannot be changed.
+		if [ $(devlink_trap_type_get $trap_name) = "drop" ]; then
+			devlink_trap_action_set $trap_name "trap"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "trap" ]; then
+				check_err 1 "Trap $trap_name did not change action to trap"
+			fi
+
+			devlink_trap_action_set $trap_name "drop"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "drop" ]; then
+				check_err 1 "Trap $trap_name did not change action to drop"
+			fi
+		else
+			orig_action=$(devlink_trap_action_get $trap_name)
+
+			devlink_trap_action_set $trap_name "trap"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != $orig_action ]; then
+				check_err 1 "Trap $trap_name changed action when should not"
+			fi
+
+			devlink_trap_action_set $trap_name "drop"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != $orig_action ]; then
+				check_err 1 "Trap $trap_name changed action when should not"
+			fi
+		fi
+	done
+
+	log_test "Trap action"
+}
+
+trap_metadata_test()
+{
+	local trap_name
+
+	RET=0
+
+	for trap_name in $(devlink_traps_get); do
+		devlink_trap_metadata_test $trap_name "input_port"
+		check_err $? "Input port not reported as metadata of trap $trap_name"
+	done
+
+	log_test "Trap metadata"
+}
+
+bad_trap_test()
+{
+	RET=0
+
+	devlink_trap_action_set "made_up_trap" "drop"
+	check_fail $? "Did not get an error for non-existing trap"
+
+	log_test "Non-existing trap"
+}
+
+bad_trap_action_test()
+{
+	local traps_arr
+	local trap_name
+
+	RET=0
+
+	# Pick first trap.
+	traps_arr=($(devlink_traps_get))
+	trap_name=${traps_arr[0]}
+
+	devlink_trap_action_set $trap_name "made_up_action"
+	check_fail $? "Did not get an error for non-existing trap action"
+
+	log_test "Non-existing trap action"
+}
+
+trap_stats_test()
+{
+	local trap_name
+
+	RET=0
+
+	for trap_name in $(devlink_traps_get); do
+		devlink_trap_stats_idle_test $trap_name
+		check_err $? "Stats of trap $trap_name not idle when netdev down"
+
+		ip link set dev $NETDEV up
+
+		if [ $(devlink_trap_type_get $trap_name) = "drop" ]; then
+			devlink_trap_action_set $trap_name "trap"
+			devlink_trap_stats_idle_test $trap_name
+			check_fail $? "Stats of trap $trap_name idle when action is trap"
+
+			devlink_trap_action_set $trap_name "drop"
+			devlink_trap_stats_idle_test $trap_name
+			check_err $? "Stats of trap $trap_name not idle when action is drop"
+		else
+			devlink_trap_stats_idle_test $trap_name
+			check_fail $? "Stats of non-drop trap $trap_name idle when should not"
+		fi
+
+		ip link set dev $NETDEV down
+	done
+
+	log_test "Trap statistics"
+}
+
+trap_group_action_test()
+{
+	local curr_group group_name
+	local trap_name
+	local trap_type
+	local action
+
+	RET=0
+
+	for group_name in $(devlink_trap_groups_get); do
+		devlink_trap_group_action_set $group_name "trap"
+
+		for trap_name in $(devlink_traps_get); do
+			curr_group=$(devlink_trap_group_get $trap_name)
+			if [ $curr_group != $group_name ]; then
+				continue
+			fi
+
+			trap_type=$(devlink_trap_type_get $trap_name)
+			if [ $trap_type != "drop" ]; then
+				continue
+			fi
+
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "trap" ]; then
+				check_err 1 "Trap $trap_name did not change action to trap"
+			fi
+		done
+
+		devlink_trap_group_action_set $group_name "drop"
+
+		for trap_name in $(devlink_traps_get); do
+			curr_group=$(devlink_trap_group_get $trap_name)
+			if [ $curr_group != $group_name ]; then
+				continue
+			fi
+
+			trap_type=$(devlink_trap_type_get $trap_name)
+			if [ $trap_type != "drop" ]; then
+				continue
+			fi
+
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "drop" ]; then
+				check_err 1 "Trap $trap_name did not change action to drop"
+			fi
+		done
+	done
+
+	log_test "Trap group action"
+}
+
+bad_trap_group_test()
+{
+	RET=0
+
+	devlink_trap_group_action_set "made_up_trap_group" "drop"
+	check_fail $? "Did not get an error for non-existing trap group"
+
+	log_test "Non-existing trap group"
+}
+
+trap_group_stats_test()
+{
+	local group_name
+
+	RET=0
+
+	for group_name in $(devlink_trap_groups_get); do
+		devlink_trap_group_stats_idle_test $group_name
+		check_err $? "Stats of trap group $group_name not idle when netdev down"
+
+		ip link set dev $NETDEV up
+
+		devlink_trap_group_action_set $group_name "trap"
+		devlink_trap_group_stats_idle_test $group_name
+		check_fail $? "Stats of trap group $group_name idle when action is trap"
+
+		devlink_trap_group_action_set $group_name "drop"
+		ip link set dev $NETDEV down
+	done
+
+	log_test "Trap group statistics"
+}
+
+port_del_test()
+{
+	local group_name
+	local i
+
+	# The test never fails. It is meant to exercise different code paths
+	# and make sure we properly dismantle a port while packets are
+	# in-flight.
+	RET=0
+
+	devlink_traps_enable_all
+
+	for i in $(seq 1 10); do
+		ip link set dev $NETDEV up
+
+		sleep $SLEEP_TIME
+
+		netdevsim_port_destroy
+		netdevsim_port_create
+		udevadm settle
+	done
+
+	devlink_traps_disable_all
+
+	log_test "Port delete"
+}
+
+dev_del_test()
+{
+	local group_name
+	local i
+
+	# The test never fails. It is meant to exercise different code paths
+	# and make sure we properly unregister traps while packets are
+	# in-flight.
+	RET=0
+
+	devlink_traps_enable_all
+
+	for i in $(seq 1 10); do
+		ip link set dev $NETDEV up
+
+		sleep $SLEEP_TIME
+
+		cleanup
+		setup_prepare
+	done
+
+	devlink_traps_disable_all
+
+	log_test "Device delete"
+}
+
+netdevsim_dev_create()
+{
+	echo "$DEV_ADDR 0" > ${NETDEVSIM_PATH}/new_device
+}
+
+netdevsim_dev_destroy()
+{
+	echo "$DEV_ADDR" > ${NETDEVSIM_PATH}/del_device
+}
+
+netdevsim_port_create()
+{
+	echo 1 > ${NETDEVSIM_PATH}/devices/${DEV}/new_port
+}
+
+netdevsim_port_destroy()
+{
+	echo 1 > ${NETDEVSIM_PATH}/devices/${DEV}/del_port
+}
+
+setup_prepare()
+{
+	local netdev
+
+	netdevsim_dev_create
+
+	if [ ! -d "${NETDEVSIM_PATH}/devices/${DEV}" ]; then
+		echo "Failed to create netdevsim device"
+		exit 1
+	fi
+
+	netdevsim_port_create
+
+	if [ ! -d "${NETDEVSIM_PATH}/devices/${DEV}/net/" ]; then
+		echo "Failed to create netdevsim port"
+		exit 1
+	fi
+
+	# Wait for udev to rename newly created netdev.
+	udevadm settle
+
+	NETDEV=$(ls ${NETDEVSIM_PATH}/devices/${DEV}/net/)
+}
+
+cleanup()
+{
+	pre_cleanup
+	netdevsim_port_destroy
+	netdevsim_dev_destroy
+}
+
+trap cleanup EXIT
+
+setup_prepare
+
+tests_run
+
+exit $EXIT_STATUS