Merge branch 'selftests-virtio_net-introduce-initial-testing-infrastructure'

Jiri Pirko says:

====================
selftests: virtio_net: introduce initial testing infrastructure

This patchset aims at introducing very basic initial infrastructure
for virtio_net testing, namely it focuses on virtio feature testing.

The first patch adds support for debugfs for virtio devices, allowing
user to filter features to pretend to be driver that is not capable
of the filtered feature.

Example:
$ cat /sys/bus/virtio/devices/virtio0/features
1110010111111111111101010000110010000000100000000000000000000000
$ echo "5" >/sys/kernel/debug/virtio/virtio0/filter_feature_add
$ cat /sys/kernel/debug/virtio/virtio0/filter_features
5
$ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/unbind
$ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/bind
$ cat /sys/bus/virtio/devices/virtio0/features
1110000111111111111101010000110010000000100000000000000000000000

Leverage that in the last patch that lays ground for virtio_net
selftests testing, including very basic F_MAC feature test.

To run this, do:
$ make -C tools/testing/selftests/ TARGETS=drivers/net/virtio_net/ run_tests

It is assumed, as with lot of other selftests in the net group,
that there are netdevices connected back-to-back. In this case,
two virtio_net devices connected back to back. If you use "tap" qemu
netdevice type, to configure this loop on a hypervisor, one may use
this script:

DEV1="$1"
DEV2="$2"

sudo tc qdisc add dev $DEV1 clsact
sudo tc qdisc add dev $DEV2 clsact
sudo tc filter add dev $DEV1 ingress protocol all pref 1 matchall action mirred egress redirect dev $DEV2
sudo tc filter add dev $DEV2 ingress protocol all pref 1 matchall action mirred egress redirect dev $DEV1
sudo ip link set $DEV1 up
sudo ip link set $DEV2 up

Another possibility is to use virtme-ng like this:
$ vng --network=loop
or directly:
$ vng --network=loop -- make -C tools/testing/selftests/ TARGETS=drivers/net/virtio_net/ run_tests

"loop" network type will take care of creating two "hubport" qemu netdevs
putting them into a single hub.

To do it manually with qemu, pass following command line options:
-nic hubport,hubid=1,id=nd0,model=virtio-net-pci
-nic hubport,hubid=1,id=nd1,model=virtio-net-pci
====================

Link: https://lore.kernel.org/r/20240424104049.3935572-1-jiri@resnulli.us
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

6 files changed, 310 insertions, 0 deletions

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index c785b6256a45..2c940e9c4ced 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -20,6 +20,7 @@ TARGETS += drivers/s390x/uvdevice
 TARGETS += drivers/net
 TARGETS += drivers/net/bonding
 TARGETS += drivers/net/team
+TARGETS += drivers/net/virtio_net
 TARGETS += dt
 TARGETS += efivarfs
 TARGETS += exec
diff --git a/tools/testing/selftests/drivers/net/virtio_net/Makefile b/tools/testing/selftests/drivers/net/virtio_net/Makefile
new file mode 100644
index 000000000000..7ec7cd3ab2cc
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/virtio_net/Makefile
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0+ OR MIT
+
+TEST_PROGS = basic_features.sh \
+        #
+
+TEST_FILES = \
+        virtio_net_common.sh \
+        #
+
+TEST_INCLUDES = \
+        ../../../net/forwarding/lib.sh \
+        ../../../net/lib.sh \
+        #
+
+include ../../../lib.mk
diff --git a/tools/testing/selftests/drivers/net/virtio_net/basic_features.sh b/tools/testing/selftests/drivers/net/virtio_net/basic_features.sh
new file mode 100755
index 000000000000..cf8cf816ed48
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/virtio_net/basic_features.sh
@@ -0,0 +1,131 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# See virtio_net_common.sh comments for more details about assumed setup
+
+ALL_TESTS="
+	initial_ping_test
+	f_mac_test
+"
+
+source virtio_net_common.sh
+
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
+
+h1=${NETIFS[p1]}
+h2=${NETIFS[p2]}
+
+h1_create()
+{
+	simple_if_init $h1 $H1_IPV4/24 $H1_IPV6/64
+}
+
+h1_destroy()
+{
+	simple_if_fini $h1 $H1_IPV4/24 $H1_IPV6/64
+}
+
+h2_create()
+{
+	simple_if_init $h2 $H2_IPV4/24 $H2_IPV6/64
+}
+
+h2_destroy()
+{
+	simple_if_fini $h2 $H2_IPV4/24 $H2_IPV6/64
+}
+
+initial_ping_test()
+{
+	setup_cleanup
+	setup_prepare
+	ping_test $h1 $H2_IPV4 " simple"
+}
+
+f_mac_test()
+{
+	RET=0
+	local test_name="mac feature filtered"
+
+	virtio_feature_present $h1 $VIRTIO_NET_F_MAC
+	if [ $? -ne 0 ]; then
+		log_test_skip "$test_name" "Device $h1 is missing feature $VIRTIO_NET_F_MAC."
+		return 0
+	fi
+	virtio_feature_present $h1 $VIRTIO_NET_F_MAC
+	if [ $? -ne 0 ]; then
+		log_test_skip "$test_name" "Device $h2 is missing feature $VIRTIO_NET_F_MAC."
+		return 0
+	fi
+
+	setup_cleanup
+	setup_prepare
+
+	grep -q 0 /sys/class/net/$h1/addr_assign_type
+	check_err $? "Permanent address assign type for $h1 is not set"
+	grep -q 0 /sys/class/net/$h2/addr_assign_type
+	check_err $? "Permanent address assign type for $h2 is not set"
+
+	setup_cleanup
+	virtio_filter_feature_add $h1 $VIRTIO_NET_F_MAC
+	virtio_filter_feature_add $h2 $VIRTIO_NET_F_MAC
+	setup_prepare
+
+	grep -q 0 /sys/class/net/$h1/addr_assign_type
+	check_fail $? "Permanent address assign type for $h1 is set when F_MAC feature is filtered"
+	grep -q 0 /sys/class/net/$h2/addr_assign_type
+	check_fail $? "Permanent address assign type for $h2 is set when F_MAC feature is filtered"
+
+	ping_do $h1 $H2_IPV4
+	check_err $? "Ping failed"
+
+	log_test "$test_name"
+}
+
+setup_prepare()
+{
+	virtio_device_rebind $h1
+	virtio_device_rebind $h2
+	wait_for_dev $h1
+	wait_for_dev $h2
+
+	vrf_prepare
+
+	h1_create
+	h2_create
+}
+
+setup_cleanup()
+{
+	h2_destroy
+	h1_destroy
+
+	vrf_cleanup
+
+	virtio_filter_features_clear $h1
+	virtio_filter_features_clear $h2
+	virtio_device_rebind $h1
+	virtio_device_rebind $h2
+	wait_for_dev $h1
+	wait_for_dev $h2
+}
+
+cleanup()
+{
+	pre_cleanup
+	setup_cleanup
+}
+
+check_driver $h1 "virtio_net"
+check_driver $h2 "virtio_net"
+check_virtio_debugfs $h1
+check_virtio_debugfs $h2
+
+trap cleanup EXIT
+
+setup_prepare
+
+tests_run
+
+exit "$EXIT_STATUS"
diff --git a/tools/testing/selftests/drivers/net/virtio_net/config b/tools/testing/selftests/drivers/net/virtio_net/config
new file mode 100644
index 000000000000..f35de0542b60
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/virtio_net/config
@@ -0,0 +1,2 @@
+CONFIG_VIRTIO_NET=y
+CONFIG_VIRTIO_DEBUG=y
diff --git a/tools/testing/selftests/drivers/net/virtio_net/virtio_net_common.sh b/tools/testing/selftests/drivers/net/virtio_net/virtio_net_common.sh
new file mode 100644
index 000000000000..57bd8055e2e5
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/virtio_net/virtio_net_common.sh
@@ -0,0 +1,99 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# This assumes running on a host with two virtio interfaces connected
+# back to back. Example script to do such wire-up of tap devices would
+# look like this:
+#
+# =======================================================================================================
+# #!/bin/bash
+#
+# DEV1="$1"
+# DEV2="$2"
+#
+# sudo tc qdisc add dev $DEV1 clsact
+# sudo tc qdisc add dev $DEV2 clsact
+# sudo tc filter add dev $DEV1 ingress protocol all pref 1 matchall action mirred egress redirect dev $DEV2
+# sudo tc filter add dev $DEV2 ingress protocol all pref 1 matchall action mirred egress redirect dev $DEV1
+# sudo ip link set $DEV1 up
+# sudo ip link set $DEV2 up
+# =======================================================================================================
+
+REQUIRE_MZ="no"
+NETIF_CREATE="no"
+NETIF_FIND_DRIVER="virtio_net"
+NUM_NETIFS=2
+
+H1_IPV4="192.0.2.1"
+H2_IPV4="192.0.2.2"
+H1_IPV6="2001:db8:1::1"
+H2_IPV6="2001:db8:1::2"
+
+VIRTIO_NET_F_MAC=5
+
+virtio_device_get()
+{
+	local dev=$1; shift
+	local device_path="/sys/class/net/$dev/device/"
+
+	basename `realpath $device_path`
+}
+
+virtio_device_rebind()
+{
+	local dev=$1; shift
+	local device=`virtio_device_get $dev`
+
+	echo "$device" > /sys/bus/virtio/drivers/virtio_net/unbind
+	echo "$device" > /sys/bus/virtio/drivers/virtio_net/bind
+}
+
+virtio_debugfs_get()
+{
+	local dev=$1; shift
+	local device=`virtio_device_get $dev`
+
+	echo /sys/kernel/debug/virtio/$device/
+}
+
+check_virtio_debugfs()
+{
+	local dev=$1; shift
+	local debugfs=`virtio_debugfs_get $dev`
+
+	if [ ! -f "$debugfs/device_features" ] ||
+	   [ ! -f "$debugfs/filter_feature_add"  ] ||
+	   [ ! -f "$debugfs/filter_feature_del"  ] ||
+	   [ ! -f "$debugfs/filter_features"  ] ||
+	   [ ! -f "$debugfs/filter_features_clear"  ]; then
+		echo "SKIP: not possible to access debugfs for $dev"
+		exit $ksft_skip
+	fi
+}
+
+virtio_feature_present()
+{
+	local dev=$1; shift
+	local feature=$1; shift
+	local debugfs=`virtio_debugfs_get $dev`
+
+	cat $debugfs/device_features |grep "^$feature$" &> /dev/null
+	return $?
+}
+
+virtio_filter_features_clear()
+{
+	local dev=$1; shift
+	local debugfs=`virtio_debugfs_get $dev`
+
+	echo "1" > $debugfs/filter_features_clear
+}
+
+virtio_filter_feature_add()
+{
+	local dev=$1; shift
+	local feature=$1; shift
+	local debugfs=`virtio_debugfs_get $dev`
+
+	echo "$feature" > $debugfs/filter_feature_add
+}
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index 7913c6ee418d..3353a1745946 100644
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -84,6 +84,43 @@ declare -A NETIFS=(
 # e.g. a low-power board.
 : "${KSFT_MACHINE_SLOW:=no}"
 
+##############################################################################
+# Find netifs by test-specified driver name
+
+driver_name_get()
+{
+	local dev=$1; shift
+	local driver_path="/sys/class/net/$dev/device/driver"
+
+	if [[ -L $driver_path ]]; then
+		basename `realpath $driver_path`
+	fi
+}
+
+netif_find_driver()
+{
+	local ifnames=`ip -j link show | jq -r ".[].ifname"`
+	local count=0
+
+	for ifname in $ifnames
+	do
+		local driver_name=`driver_name_get $ifname`
+		if [[ ! -z $driver_name && $driver_name == $NETIF_FIND_DRIVER ]]; then
+			count=$((count + 1))
+			NETIFS[p$count]="$ifname"
+		fi
+	done
+}
+
+# Whether to find netdevice according to the driver speficied by the importer
+: "${NETIF_FIND_DRIVER:=}"
+
+if [[ $NETIF_FIND_DRIVER ]]; then
+	unset NETIFS
+	declare -A NETIFS
+	netif_find_driver
+fi
+
 net_forwarding_dir=$(dirname "$(readlink -e "${BASH_SOURCE[0]}")")
 
 if [[ -f $net_forwarding_dir/forwarding.config ]]; then
@@ -246,6 +283,18 @@ if [[ "$(id -u)" -ne 0 ]]; then
 	exit $ksft_skip
 fi
 
+check_driver()
+{
+	local dev=$1; shift
+	local expected=$1; shift
+	local driver_name=`driver_name_get $dev`
+
+	if [[ $driver_name != $expected ]]; then
+		echo "SKIP: expected driver $expected for $dev, got $driver_name instead"
+		exit $ksft_skip
+	fi
+}
+
 if [[ "$CHECK_TC" = "yes" ]]; then
 	check_tc_version
 fi
@@ -689,6 +738,19 @@ setup_wait()
 	sleep $WAIT_TIME
 }
 
+wait_for_dev()
+{
+        local dev=$1; shift
+        local timeout=${1:-$WAIT_TIMEOUT}; shift
+
+        slowwait $timeout ip link show dev $dev &> /dev/null
+        if (( $? )); then
+                check_err 1
+                log_test wait_for_dev "Interface $dev did not appear."
+                exit $EXIT_STATUS
+        fi
+}
+
 cmd_jq()
 {
 	local cmd=$1