selftests: test creating netdevsim inside network namespace

Add a test that creates netdevsim instance inside network namespace
and verifies that the related devlink instance and port netdevices
reside in the namespace.

Signed-off-by: Jiri Pirko <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

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

···
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+ALL_TESTS="check_devlink_test check_ports_test"
+NUM_NETIFS=0
+source $lib_dir/lib.sh
+
+BUS_ADDR=10
+PORT_COUNT=4
+DEV_NAME=netdevsim$BUS_ADDR
+SYSFS_NET_DIR=/sys/bus/netdevsim/devices/$DEV_NAME/net/
+DL_HANDLE=netdevsim/$DEV_NAME
+NETNS_NAME=testns1
+
+port_netdev_get()
+{
+	local port_index=$1
+
+	cmd_jq "devlink -N $NETNS_NAME port show -j" \
+	       ".[][\"$DL_HANDLE/$port_index\"].netdev" "-e"
+}
+
+check_ports_test()
+{
+	RET=0
+
+	for i in $(seq 0 $(expr $PORT_COUNT - 1)); do
+		netdev_name=$(port_netdev_get $i)
+		check_err $? "Failed to get netdev name for port $DL_HANDLE/$i"
+		ip -n $NETNS_NAME link show $netdev_name &> /dev/null
+		check_err $? "Failed to find netdev $netdev_name"
+	done
+
+	log_test "check ports test"
+}
+
+check_devlink_test()
+{
+	RET=0
+
+	devlink -N $NETNS_NAME dev show $DL_HANDLE &> /dev/null
+	check_err $? "Failed to show devlink instance"
+
+	log_test "check devlink test"
+}
+
+setup_prepare()
+{
+	modprobe netdevsim
+	ip netns add $NETNS_NAME
+	ip netns exec $NETNS_NAME \
+		echo "$BUS_ADDR $PORT_COUNT" > /sys/bus/netdevsim/new_device
+	while [ ! -d $SYSFS_NET_DIR ] ; do :; done
+}
+
+cleanup()
+{
+	pre_cleanup
+	echo "$BUS_ADDR" > /sys/bus/netdevsim/del_device
+	ip netns del $NETNS_NAME
+	modprobe -r netdevsim
+}
+
+trap cleanup EXIT
+
+setup_prepare
+
+tests_run
+
+exit $EXIT_STATUS

tools/testing/selftests/net/forwarding/lib.sh

···
 {
 	local cmd=$1
 	local jq_exp=$2
+	local jq_opts=$3
 	local ret
 	local output
 
···
 	if [[ $ret -ne 0 ]]; then
 		return $ret
 	fi
-	output=$(echo $output | jq -r "$jq_exp")
+	output=$(echo $output | jq -r $jq_opts "$jq_exp")
+	ret=$?
+	if [[ $ret -ne 0 ]]; then
+		return $ret
+	fi
 	echo $output
 	# return success only in case of non-empty output
 	[ ! -z "$output" ]