selftests: netdevsim: Test route offload failure notifications

Add cases to verify that when debugfs variable "fail_route_offload" is
set, notification with "rt_offload_failed" flag is received.

Extend the existing cases to verify that when sysctl
"fib_notify_on_flag_change" is set to 2, the kernel emits notifications
only for failed route installation.

$ ./fib_notifications.sh
TEST: IPv4 route addition [ OK ]
TEST: IPv4 route deletion [ OK ]
TEST: IPv4 route replacement [ OK ]
TEST: IPv4 route offload failed [ OK ]
TEST: IPv6 route addition [ OK ]
TEST: IPv6 route deletion [ OK ]
TEST: IPv6 route replacement [ OK ]
TEST: IPv6 route offload failed [ OK ]

Signed-off-by: Amit Cohen <[e-mail]>
Signed-off-by: Ido Schimmel <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

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

···
 	ipv4_route_addition_test
 	ipv4_route_deletion_test
 	ipv4_route_replacement_test
+	ipv4_route_offload_failed_test
 	ipv6_route_addition_test
 	ipv6_route_deletion_test
 	ipv6_route_replacement_test
+	ipv6_route_offload_failed_test
 "
 
 NETDEVSIM_PATH=/sys/bus/netdevsim/
···
 DEV=netdevsim${DEV_ADDR}
 DEVLINK_DEV=netdevsim/${DEV}
 SYSFS_NET_DIR=/sys/bus/netdevsim/devices/$DEV/net/
+DEBUGFS_DIR=/sys/kernel/debug/netdevsim/$DEV/
 NUM_NETIFS=0
 source $lib_dir/lib.sh
+
+check_rt_offload_failed()
+{
+	local outfile=$1; shift
+	local line
+
+	# Make sure that the first notification was emitted without
+	# RTM_F_OFFLOAD_FAILED flag and the second with RTM_F_OFFLOAD_FAILED
+	# flag
+	head -n 1 $outfile | grep -q "rt_offload_failed"
+	if [[ $? -eq 0 ]]; then
+		return 1
+	fi
+
+	head -n 2 $outfile | tail -n 1 | grep -q "rt_offload_failed"
+}
 
 check_rt_trap()
 {
···
 {
 	local outfile=$1; shift
 	local expected_num_lines=$1; shift
+	local offload_failed=${1:-0}; shift
 
 	# check the monitor results
 	lines=`wc -l $outfile | cut "-d " -f1`
 	test $lines -eq $expected_num_lines
 	check_err $? "$expected_num_lines notifications were expected but $lines were received"
 
-	if [[ $expected_num_lines -eq 2 ]]; then
+	if [[ $expected_num_lines -eq 1 ]]; then
+		return
+	fi
+
+	if [[ $offload_failed -eq 0 ]]; then
 		check_rt_trap $outfile
 		check_err $? "Wrong RTM_F_TRAP flags in notifications"
+	else
+		check_rt_offload_failed $outfile
+		check_err $? "Wrong RTM_F_OFFLOAD_FAILED flags in notifications"
 	fi
 }
 
···
 	local notify=$1; shift
 	local route=$1; shift
 	local expected_num_notifications=$1; shift
+	local offload_failed=${1:-0}; shift
 
 	ip netns exec testns1 sysctl -qw net.$ip.fib_notify_on_flag_change=$notify
 
···
 	sleep 1
 	kill %% && wait %% &> /dev/null
 
-	route_notify_check $outfile $expected_num_notifications
+	route_notify_check $outfile $expected_num_notifications $offload_failed
 	rm -f $outfile
 
 	$IP route del $route dev dummy1
···
 	# Make sure two notifications will be emitted for the programmed route.
 	notify=1
 	expected_num_notifications=2
+	route_addition_check $ip $notify $route $expected_num_notifications
+
+	# notify=2 means emit notifications only for failed route installation,
+	# make sure a single notification will be emitted for the programmed
+	# route.
+	notify=2
+	expected_num_notifications=1
 	route_addition_check $ip $notify $route $expected_num_notifications
 
 	log_test "IPv4 route addition"
···
 	expected_num_notifications=2
 	route_replacement_check $ip $notify $route $expected_num_notifications
 
+	# notify=2 means emit notifications only for failed route installation,
+	# make sure a single notification will be emitted for the new route.
+	notify=2
+	expected_num_notifications=1
+	route_replacement_check $ip $notify $route $expected_num_notifications
+
 	$IP link del name dummy2
 
 	log_test "IPv4 route replacement"
+}
+
+ipv4_route_offload_failed_test()
+{
+
+	RET=0
+
+	local ip="ipv4"
+	local route=192.0.2.0/24
+	local offload_failed=1
+
+	echo "y"> $DEBUGFS_DIR/fib/fail_route_offload
+	check_err $? "Failed to setup route offload to fail"
+
+	# Make sure a single notification will be emitted for the programmed
+	# route.
+	local notify=0
+	local expected_num_notifications=1
+	route_addition_check $ip $notify $route $expected_num_notifications \
+		$offload_failed
+
+	# Make sure two notifications will be emitted for the new route.
+	notify=1
+	expected_num_notifications=2
+	route_addition_check $ip $notify $route $expected_num_notifications \
+		$offload_failed
+
+	# notify=2 means emit notifications only for failed route installation,
+	# make sure two notifications will be emitted for the new route.
+	notify=2
+	expected_num_notifications=2
+	route_addition_check $ip $notify $route $expected_num_notifications \
+		$offload_failed
+
+	echo "n"> $DEBUGFS_DIR/fib/fail_route_offload
+	check_err $? "Failed to setup route offload not to fail"
+
+	log_test "IPv4 route offload failed"
 }
 
 ipv6_route_addition_test()
···
 	# Make sure two notifications will be emitted for the programmed route.
 	notify=1
 	expected_num_notifications=2
+	route_addition_check $ip $notify $route $expected_num_notifications
+
+	# notify=2 means emit notifications only for failed route installation,
+	# make sure a single notification will be emitted for the programmed
+	# route.
+	notify=2
+	expected_num_notifications=1
 	route_addition_check $ip $notify $route $expected_num_notifications
 
 	log_test "IPv6 route addition"
···
 	expected_num_notifications=2
 	route_replacement_check $ip $notify $route $expected_num_notifications
 
+	# notify=2 means emit notifications only for failed route installation,
+	# make sure a single notification will be emitted for the new route.
+	notify=2
+	expected_num_notifications=1
+	route_replacement_check $ip $notify $route $expected_num_notifications
+
 	$IP link del name dummy2
 
 	log_test "IPv6 route replacement"
+}
+
+ipv6_route_offload_failed_test()
+{
+
+	RET=0
+
+	local ip="ipv6"
+	local route=2001:db8:1::/64
+	local offload_failed=1
+
+	echo "y"> $DEBUGFS_DIR/fib/fail_route_offload
+	check_err $? "Failed to setup route offload to fail"
+
+	# Make sure a single notification will be emitted for the programmed
+	# route.
+	local notify=0
+	local expected_num_notifications=1
+	route_addition_check $ip $notify $route $expected_num_notifications \
+		$offload_failed
+
+	# Make sure two notifications will be emitted for the new route.
+	notify=1
+	expected_num_notifications=2
+	route_addition_check $ip $notify $route $expected_num_notifications \
+		$offload_failed
+
+	# notify=2 means emit notifications only for failed route installation,
+	# make sure two notifications will be emitted for the new route.
+	notify=2
+	expected_num_notifications=2
+	route_addition_check $ip $notify $route $expected_num_notifications \
+		$offload_failed
+
+	echo "n"> $DEBUGFS_DIR/fib/fail_route_offload
+	check_err $? "Failed to setup route offload not to fail"
+
+	log_test "IPv6 route offload failed"
 }
 
 setup_prepare()