selftests: forwarding: Add helpers and tests for FIB offload

Implement a set of common helpers and tests for FIB offload that can be
used by multiple drivers to check their FIB offload implementations.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

+# SPDX-License-Identifier: GPL-2.0
+#
+# Various helpers and tests to verify FIB offload.
+
+__fib_trap_check()
+{
+	local ns=$1; shift
+	local family=$1; shift
+	local route=$1; shift
+	local should_fail=$1; shift
+	local ret
+
+	ip -n $ns -j -p -$family route show $route \
+		| jq -e '.[]["flags"] | contains(["trap"])' &> /dev/null
+	ret=$?
+	if [[ $should_fail == "true" ]]; then
+		if [[ $ret -ne 0 ]]; then
+			return 0
+		else
+			return 1
+		fi
+	fi
+
+	return $ret
+}
+
+fib_trap_check()
+{
+	local ns=$1; shift
+	local family=$1; shift
+	local route=$1; shift
+	local should_fail=$1; shift
+
+	busywait 5000 __fib_trap_check $ns $family "$route" $should_fail
+}
+
+fib4_trap_check()
+{
+	local ns=$1; shift
+	local route=$1; shift
+	local should_fail=$1; shift
+
+	fib_trap_check $ns 4 "$route" $should_fail
+}
+
+fib6_trap_check()
+{
+	local ns=$1; shift
+	local route=$1; shift
+	local should_fail=$1; shift
+
+	fib_trap_check $ns 6 "$route" $should_fail
+}
+
+fib_ipv4_identical_routes_test()
+{
+	local ns=$1; shift
+	local i
+
+	RET=0
+
+	for i in $(seq 1 3); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+	done
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 tos 0 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 0 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route append 192.0.2.0/24 dev dummy2 tos 0 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy2 tos 0 metric 1024" true
+	check_err $? "Appended route in hardware when should not"
+
+	ip -n $ns route prepend 192.0.2.0/24 dev dummy3 tos 0 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy3 tos 0 metric 1024" false
+	check_err $? "Prepended route not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 0 metric 1024" true
+	check_err $? "Route was not replaced in hardware by prepended one"
+
+	log_test "IPv4 identical routes"
+
+	for i in $(seq 1 3); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv4_tos_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 tos 0 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 0 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 tos 2 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 2 metric 1024" false
+	check_err $? "Highest TOS route not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 0 metric 1024" true
+	check_err $? "Lowest TOS route still in hardware when should not"
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 tos 1 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 1 metric 1024" true
+	check_err $? "Middle TOS route in hardware when should not"
+
+	log_test "IPv4 routes with TOS"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_metric_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1022
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1022" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1024" true
+	check_err $? "Highest metric route still in hardware when should not"
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1023
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1023" true
+	check_err $? "Middle metric route in hardware when should not"
+
+	log_test "IPv4 routes with metric"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_replace_test()
+{
+	local ns=$1; shift
+	local i
+
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+	done
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route replace 192.0.2.0/24 dev dummy2 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy2 metric 1024" false
+	check_err $? "Replacement route not in hardware when should"
+
+	# Add a route with an higher metric and make sure that replacing it
+	# does not affect the lower metric one.
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1025
+	ip -n $ns route replace 192.0.2.0/24 dev dummy2 metric 1025
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy2 metric 1024" false
+	check_err $? "Lowest metric route not in hardware when should"
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy2 metric 1025" true
+	check_err $? "Highest metric route in hardware when should not"
+
+	log_test "IPv4 route replace"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv4_delete_test()
+{
+	local ns=$1; shift
+	local metric
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	# Insert multiple routes with the same prefix and length and varying
+	# metrics. Make sure that throughout delete operations the lowest
+	# metric route is the one in hardware.
+	for metric in $(seq 1024 1026); do
+		ip -n $ns route add 192.0.2.0/24 dev dummy1 metric $metric
+	done
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route del 192.0.2.0/24 dev dummy1 metric 1024
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1025" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	ip -n $ns route del 192.0.2.0/24 dev dummy1 metric 1026
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1025" false
+	check_err $? "Sole route not in hardware when should"
+
+	log_test "IPv4 route delete"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_plen_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	# Add two routes with the same key and different prefix length and
+	# make sure both are in hardware. It can be verfied that both are
+	# sharing the same leaf by checking the /proc/net/fib_trie
+	ip -n $ns route add 192.0.2.0/24 dev dummy1
+	ip -n $ns route add 192.0.2.0/25 dev dummy1
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1" false
+	check_err $? "/24 not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/25 dev dummy1" false
+	check_err $? "/25 not in hardware when should"
+
+	log_test "IPv4 routes with different prefix length"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_replay_metric_test()
+{
+	local ns=$1; shift
+	local devlink_dev=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1024
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 metric 1025
+
+	devlink -N $ns dev reload $devlink_dev
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1024" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 metric 1025" true
+	check_err $? "Highest metric route in hardware when should not"
+
+	log_test "IPv4 routes replay - metric"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_replay_tos_test()
+{
+	local ns=$1; shift
+	local devlink_dev=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 tos 0
+	ip -n $ns route add 192.0.2.0/24 dev dummy1 tos 1
+
+	devlink -N $ns dev reload $devlink_dev
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 1" false
+	check_err $? "Highest TOS route not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1 tos 0" true
+	check_err $? "Lowest TOS route in hardware when should not"
+
+	log_test "IPv4 routes replay - TOS"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_replay_plen_test()
+{
+	local ns=$1; shift
+	local devlink_dev=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	ip -n $ns route add 192.0.2.0/24 dev dummy1
+	ip -n $ns route add 192.0.2.0/25 dev dummy1
+
+	devlink -N $ns dev reload $devlink_dev
+
+	fib4_trap_check $ns "192.0.2.0/24 dev dummy1" false
+	check_err $? "/24 not in hardware when should"
+
+	fib4_trap_check $ns "192.0.2.0/25 dev dummy1" false
+	check_err $? "/25 not in hardware when should"
+
+	log_test "IPv4 routes replay - prefix length"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv4_flush_test()
+{
+	local ns=$1; shift
+	local metric
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	# Exercise the routes flushing code paths by inserting various
+	# prefix routes on a netdev and then deleting it.
+	for metric in $(seq 1 20); do
+		ip -n $ns route add 192.0.2.0/24 dev dummy1 metric $metric
+	done
+
+	ip -n $ns link del dev dummy1
+
+	log_test "IPv4 routes flushing"
+}
+
+fib_ipv6_add_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+	done
+
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1 metric 1024
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route append 2001:db8:1::/64 dev dummy2 metric 1024
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy2 metric 1024" true
+	check_err $? "Route in hardware when should not"
+
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware after appending route"
+
+	log_test "IPv6 single route add"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_metric_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	ip -n $ns link add name dummy1 type dummy
+	ip -n $ns link set dev dummy1 up
+
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1 metric 1024
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1 metric 1022
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1022" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1024" true
+	check_err $? "Highest metric route still in hardware when should not"
+
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1 metric 1023
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1023" true
+	check_err $? "Middle metric route in hardware when should not"
+
+	log_test "IPv6 routes with metric"
+
+	ip -n $ns link del dev dummy1
+}
+
+fib_ipv6_append_single_test()
+{
+	local ns=$1; shift
+
+	# When an IPv6 multipath route is added without the 'nexthop' keyword,
+	# different code paths are taken compared to when the keyword is used.
+	# This test tries to verify the former.
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	ip -n $ns route add 2001:db8:10::/64 via 2001:db8:1::2 metric 1024
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route append 2001:db8:10::/64 via 2001:db8:2::2 metric 1024
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware after appending"
+
+	ip -n $ns route add 2001:db8:10::/64 via 2001:db8:1::2 metric 1025
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" true
+	check_err $? "Route in hardware when should not"
+
+	ip -n $ns route append 2001:db8:10::/64 via 2001:db8:2::2 metric 1025
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" true
+	check_err $? "Route in hardware when should not after appending"
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	log_test "IPv6 append single route without 'nexthop' keyword"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_replace_single_test()
+{
+	local ns=$1; shift
+	local i
+
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+	done
+
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1 metric 1024
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route replace 2001:db8:1::/64 dev dummy2 metric 1024
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy2 metric 1024" false
+	check_err $? "Replacement route not in hardware when should"
+
+	# Add a route with an higher metric and make sure that replacing it
+	# does not affect the lower metric one.
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1 metric 1025
+	ip -n $ns route replace 2001:db8:1::/64 dev dummy2 metric 1025
+
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy2 metric 1024" false
+	check_err $? "Lowest metric route not in hardware when should"
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy2 metric 1025" true
+	check_err $? "Highest metric route in hardware when should not"
+
+	log_test "IPv6 single route replace"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_metric_multipath_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1022 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1022" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1023 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" true
+	check_err $? "Highest metric route still in hardware when should not"
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1023" true
+	check_err $? "Middle metric route in hardware when should not"
+
+	log_test "IPv6 multipath routes with metric"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_append_multipath_test()
+{
+	local ns=$1; shift
+
+	RET=0
+
+	for i in $(seq 1 3); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route append 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:2::2 dev dummy2 \
+		nexthop via 2001:db8:3::2 dev dummy3
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware after appending"
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" true
+	check_err $? "Route in hardware when should not"
+
+	ip -n $ns route append 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:2::2 dev dummy2 \
+		nexthop via 2001:db8:3::2 dev dummy3
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" true
+	check_err $? "Route in hardware when should not after appending"
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Lowest metric route not in hardware when should"
+
+	log_test "IPv6 append multipath route with 'nexthop' keyword"
+
+	for i in $(seq 1 3); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_replace_multipath_test()
+{
+	local ns=$1; shift
+	local i
+
+	RET=0
+
+	for i in $(seq 1 3); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route replace 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:3::2 dev dummy3
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Replacement route not in hardware when should"
+
+	# Add a route with an higher metric and make sure that replacing it
+	# does not affect the lower metric one.
+	ip -n $ns route add 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route replace 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:3::2 dev dummy3
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Lowest metric route not in hardware when should"
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" true
+	check_err $? "Highest metric route in hardware when should not"
+
+	log_test "IPv6 multipath route replace"
+
+	for i in $(seq 1 3); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_append_multipath_to_single_test()
+{
+	local ns=$1; shift
+
+	# Test that when the first route in the leaf is not a multipath route
+	# and we try to append a multipath route with the same metric to it, it
+	# is not notified.
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1024
+	fib6_trap_check $ns "2001:db8:10::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware when should"
+
+	ip -n $ns route append 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	fib6_trap_check $ns "2001:db8:10::/64 dev dummy2 metric 1024" true
+	check_err $? "Route in hardware when should not"
+
+	fib6_trap_check $ns "2001:db8:10::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware after append"
+
+	log_test "IPv6 append multipath route to non-multipath route"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_delete_single_test()
+{
+	local ns=$1; shift
+
+	# Test various deletion scenarios, where only a single route is
+	# deleted from the FIB node.
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	# Test deletion of a single route when it is the only route in the FIB
+	# node.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1024
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1024
+
+	log_test "IPv6 delete sole single route"
+
+	# Test that deletion of last route does not affect the first one.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1024
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1025
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1025
+
+	fib6_trap_check $ns "2001:db8:10::/64 dev dummy1 metric 1024" false
+	check_err $? "Route not in hardware after deleting higher metric route"
+
+	log_test "IPv6 delete single route not in hardware"
+
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1024
+
+	# Test that first route is replaced by next single route in the FIB
+	# node.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1024
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1025
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1024
+
+	fib6_trap_check $ns "2001:db8:10::/64 dev dummy1 metric 1025" false
+	check_err $? "Route not in hardware after deleting lowest metric route"
+
+	log_test "IPv6 delete single route - replaced by single"
+
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1025
+
+	# Test that first route is replaced by next multipath route in the FIB
+	# node.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1024
+	ip -n $ns route add 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1024
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" false
+	check_err $? "Route not in hardware after deleting lowest metric route"
+
+	log_test "IPv6 delete single route - replaced by multipath"
+
+	ip -n $ns route del 2001:db8:10::/64 metric 1025
+
+	# Test deletion of a single nexthop from a multipath route.
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route del 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware after deleting a single nexthop"
+
+	log_test "IPv6 delete single nexthop"
+
+	ip -n $ns route del 2001:db8:10::/64 metric 1024
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_delete_multipath_test()
+{
+	local ns=$1; shift
+
+	# Test various deletion scenarios, where an entire multipath route is
+	# deleted from the FIB node.
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	# Test deletion of a multipath route when it is the only route in the
+	# FIB node.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route del 2001:db8:10::/64 metric 1024
+
+	log_test "IPv6 delete sole multipath route"
+
+	# Test that deletion of last route does not affect the first one.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route add 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route del 2001:db8:10::/64 metric 1025
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "Route not in hardware after deleting higher metric route"
+
+	log_test "IPv6 delete multipath route not in hardware"
+
+	ip -n $ns route del 2001:db8:10::/64 metric 1024
+
+	# Test that first route is replaced by next single route in the FIB
+	# node.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route add 2001:db8:10::/64 dev dummy1 metric 1025
+	ip -n $ns route del 2001:db8:10::/64 metric 1024
+
+	fib6_trap_check $ns "2001:db8:10::/64 dev dummy1 metric 1025" false
+	check_err $? "Route not in hardware after deleting lowest metric route"
+
+	log_test "IPv6 delete multipath route - replaced by single"
+
+	ip -n $ns route del 2001:db8:10::/64 dev dummy1 metric 1025
+
+	# Test that first route is replaced by next multipath route in the FIB
+	# node.
+	RET=0
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route add 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route del 2001:db8:10::/64 metric 1024
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" false
+	check_err $? "Route not in hardware after deleting lowest metric route"
+
+	log_test "IPv6 delete multipath route - replaced by multipath"
+
+	ip -n $ns route del 2001:db8:10::/64 metric 1025
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_replay_single_test()
+{
+	local ns=$1; shift
+	local devlink_dev=$1; shift
+
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+	done
+
+	ip -n $ns route add 2001:db8:1::/64 dev dummy1
+	ip -n $ns route append 2001:db8:1::/64 dev dummy2
+
+	devlink -N $ns dev reload $devlink_dev
+
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy1" false
+	check_err $? "First route not in hardware when should"
+
+	fib6_trap_check $ns "2001:db8:1::/64 dev dummy2" true
+	check_err $? "Second route in hardware when should not"
+
+	log_test "IPv6 routes replay - single route"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}
+
+fib_ipv6_replay_multipath_test()
+{
+	local ns=$1; shift
+	local devlink_dev=$1; shift
+
+	RET=0
+
+	for i in $(seq 1 2); do
+		ip -n $ns link add name dummy$i type dummy
+		ip -n $ns link set dev dummy$i up
+		ip -n $ns address add 2001:db8:$i::1/64 dev dummy$i
+	done
+
+	ip -n $ns route add 2001:db8:10::/64 metric 1024 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+	ip -n $ns route add 2001:db8:10::/64 metric 1025 \
+		nexthop via 2001:db8:1::2 dev dummy1 \
+		nexthop via 2001:db8:2::2 dev dummy2
+
+	devlink -N $ns dev reload $devlink_dev
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1024" false
+	check_err $? "First route not in hardware when should"
+
+	fib6_trap_check $ns "2001:db8:10::/64 metric 1025" true
+	check_err $? "Second route in hardware when should not"
+
+	log_test "IPv6 routes replay - multipath route"
+
+	for i in $(seq 1 2); do
+		ip -n $ns link del dev dummy$i
+	done
+}