selftests: mlxsw: Add ingress RIF configuration test for 802.1Q bridge

Before layer 2 forwarding, the device classifies an incoming packet to a
FID. After classification, the FID is known, but also all the attributes of
the FID, such as the router interface (RIF) via which a packet that needs
to be routed will ingress the router block.

For VLAN-aware bridges (802.1Q), the FID classification is done according
to VID. When a RIF is added on top of a FID, the existing VID->FID mapping
should be updated by the software with the new RIF.

We never map multiple VLANs to the same FID using VID->FID, so we cannot
create VID->FID for FID which already has a RIF using 802.1Q. Anyway,
verify that packets can be routed via port which is added after the FID
already has a RIF.

Add a test to verify that packets can be routed after VID->FID
classification, regardless of the order of the configuration.

 # ./ingress_rif_conf_1q.sh
 TEST: Add RIF for existing VID->FID mapping                         [ OK ]
 TEST: Add port to VID->FID mapping for FID with a RIF               [ OK ]
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/drivers/net/mlxsw/ingress_rif_conf_1q.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Test routing over bridge and verify that the order of configuration does not
+# impact switch behavior. Verify that RIF is added correctly for existing
+# mapping and that packets can be routed via port which is added after the FID
+# already has a RIF.
+
+# +-------------------+                   +--------------------+
+# | H1                |                   | H2                 |
+# |                   |                   |                    |
+# |         $h1.10 +  |                   |  + $h2.10          |
+# |   192.0.2.1/28 |  |                   |  | 192.0.2.3/28    |
+# |                |  |                   |  |                 |
+# |            $h1 +  |                   |  + $h2             |
+# +----------------|--+                   +--|-----------------+
+#                  |                         |
+# +----------------|-------------------------|-----------------+
+# | SW             |                         |                 |
+# | +--------------|-------------------------|---------------+ |
+# | |        $swp1 +                         + $swp2         | |
+# | |                                                        | |
+# | |                           br0                          | |
+# | +--------------------------------------------------------+ |
+# |                              |                             |
+# |                           br0.10                           |
+# |                        192.0.2.2/28                        |
+# |                                                            |
+# |                                                            |
+# |          $swp3 +                                           |
+# |  192.0.2.17/28 |                                           |
+# +----------------|-------------------------------------------+
+#                  |
+# +----------------|--+
+# |            $h3 +  |
+# |  192.0.2.18/28    |
+# |                   |
+# | H3                |
+# +-------------------+
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+ALL_TESTS="
+	vid_map_rif
+	rif_vid_map
+"
+
+NUM_NETIFS=6
+source $lib_dir/lib.sh
+source $lib_dir/tc_common.sh
+source $lib_dir/devlink_lib.sh
+
+h1_create()
+{
+	simple_if_init $h1
+	vlan_create $h1 10 v$h1 192.0.2.1/28
+
+	ip route add 192.0.2.16/28 vrf v$h1 nexthop via 192.0.2.2
+}
+
+h1_destroy()
+{
+	ip route del 192.0.2.16/28 vrf v$h1 nexthop via 192.0.2.2
+
+	vlan_destroy $h1 10
+	simple_if_fini $h1
+}
+
+h2_create()
+{
+	simple_if_init $h2
+	vlan_create $h2 10 v$h2 192.0.2.3/28
+}
+
+h2_destroy()
+{
+	vlan_destroy $h2 10
+	simple_if_fini $h2
+}
+
+h3_create()
+{
+	simple_if_init $h3 192.0.2.18/28
+	ip route add 192.0.2.0/28 vrf v$h3 nexthop via 192.0.2.17
+}
+
+h3_destroy()
+{
+	ip route del 192.0.2.0/28 vrf v$h3 nexthop via 192.0.2.17
+	simple_if_fini $h3 192.0.2.18/28
+}
+
+switch_create()
+{
+	ip link set dev $swp1 up
+
+	ip link add dev br0 type bridge vlan_filtering 1 mcast_snooping 0
+
+	# By default, a link-local address is generated when netdevice becomes
+	# up. Adding an address to the bridge will cause creating a RIF for it.
+	# Prevent generating link-local address to be able to control when the
+	# RIF is added.
+	sysctl_set net.ipv6.conf.br0.addr_gen_mode 1
+	ip link set dev br0 up
+
+	ip link set dev $swp2 up
+	ip link set dev $swp2 master br0
+	bridge vlan add vid 10 dev $swp2
+
+	ip link set dev $swp3 up
+	__addr_add_del $swp3 add 192.0.2.17/28
+	tc qdisc add dev $swp3 clsact
+
+	# Replace neighbor to avoid 1 packet which is forwarded in software due
+	# to "unresolved neigh".
+	ip neigh replace dev $swp3 192.0.2.18 lladdr $(mac_get $h3)
+}
+
+switch_destroy()
+{
+	tc qdisc del dev $swp3 clsact
+	__addr_add_del $swp3 del 192.0.2.17/28
+	ip link set dev $swp3 down
+
+	bridge vlan del vid 10 dev $swp2
+	ip link set dev $swp2 nomaster
+	ip link set dev $swp2 down
+
+	ip link set dev br0 down
+	sysctl_restore net.ipv6.conf.br0.addr_gen_mode
+	ip link del dev br0
+
+	ip link set dev $swp1 down
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	swp2=${NETIFS[p3]}
+	h2=${NETIFS[p4]}
+
+	swp3=${NETIFS[p5]}
+	h3=${NETIFS[p6]}
+
+	vrf_prepare
+	forwarding_enable
+
+	h1_create
+	h2_create
+	h3_create
+
+	switch_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	switch_destroy
+
+	h3_destroy
+	h2_destroy
+	h1_destroy
+
+	forwarding_restore
+	vrf_cleanup
+}
+
+bridge_rif_add()
+{
+	rifs_occ_t0=$(devlink_resource_occ_get rifs)
+	vlan_create br0 10 "" 192.0.2.2/28
+	rifs_occ_t1=$(devlink_resource_occ_get rifs)
+
+	expected_rifs=$((rifs_occ_t0 + 1))
+
+	[[ $expected_rifs -eq $rifs_occ_t1 ]]
+	check_err $? "Expected $expected_rifs RIFs, $rifs_occ_t1 are used"
+
+	sleep 1
+}
+
+bridge_rif_del()
+{
+	vlan_destroy br0 10
+}
+
+vid_map_rif()
+{
+	RET=0
+
+	# First add VID->FID for vlan 10, then add a RIF and verify that
+	# packets can be routed via the existing mapping.
+	bridge vlan add vid 10 dev br0 self
+	ip link set dev $swp1 master br0
+	bridge vlan add vid 10 dev $swp1
+
+	bridge_rif_add
+
+	tc filter add dev $swp3 egress protocol ip pref 1 handle 101 \
+		flower skip_sw dst_ip 192.0.2.18 action pass
+
+	ping_do $h1.10 192.0.2.18
+	check_err $? "Ping failed"
+
+	tc_check_at_least_x_packets "dev $swp3 egress" 101 10
+	check_err $? "Packets were not routed in hardware"
+
+	log_test "Add RIF for existing VID->FID mapping"
+
+	tc filter del dev $swp3 egress
+
+	bridge_rif_del
+
+	bridge vlan del vid 10 dev $swp1
+	ip link set dev $swp1 nomaster
+	bridge vlan del vid 10 dev br0 self
+}
+
+rif_vid_map()
+{
+	RET=0
+
+	# Using 802.1Q, there is only one VID->FID map for each VID. That means
+	# that we cannot really check adding a new map for existing FID with a
+	# RIF. Verify that packets can be routed via port which is added after
+	# the FID already has a RIF, although in practice there is no new
+	# mapping in the hardware.
+	bridge vlan add vid 10 dev br0 self
+	bridge_rif_add
+
+	ip link set dev $swp1 master br0
+	bridge vlan add vid 10 dev $swp1
+
+	tc filter add dev $swp3 egress protocol ip pref 1 handle 101 \
+		flower skip_sw dst_ip 192.0.2.18 action pass
+
+	ping_do $h1.10 192.0.2.18
+	check_err $? "Ping failed"
+
+	tc_check_at_least_x_packets "dev $swp3 egress" 101 10
+	check_err $? "Packets were not routed in hardware"
+
+	log_test "Add port to VID->FID mapping for FID with a RIF"
+
+	tc filter del dev $swp3 egress
+
+	bridge vlan del vid 10 dev $swp1
+	ip link set dev $swp1 nomaster
+
+	bridge_rif_del
+	bridge vlan del vid 10 dev br0 self
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS