net: qos: add tc police offloading action with max frame size limit

Current police offloading support the 'burst'' and 'rate_bytes_ps'. Some
hardware own the capability to limit the frame size. If the frame size
larger than the setting, the frame would be dropped. For the police
action itself already accept the 'mtu' parameter in tc command. But not
extend to tc flower offloading. So extend 'mtu' to tc flower offloading.
Signed-off-by: Po Liu <Po.Liu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/flow_offload.h

@@ -234,6 +234,7 @@ struct flow_action_entry {
 		struct {				/* FLOW_ACTION_POLICE */
 			s64			burst;
 			u64			rate_bytes_ps;
+			u32			mtu;
 		} police;
 		struct {				/* FLOW_ACTION_CT */
 			int action;

include/net/tc_act/tc_police.h

@@ -69,4 +69,14 @@ static inline s64 tcf_police_tcfp_burst(const struct tc_action *act)
 	return params->tcfp_burst;
 }
 
+static inline u32 tcf_police_tcfp_mtu(const struct tc_action *act)
+{
+	struct tcf_police *police = to_police(act);
+	struct tcf_police_params *params;
+
+	params = rcu_dereference_protected(police->params,
+					   lockdep_is_held(&police->tcf_lock));
+	return params->tcfp_mtu;
+}
+
 #endif /* __NET_TC_POLICE_H */

net/sched/cls_api.c

@@ -3658,6 +3658,7 @@ int tc_setup_flow_action(struct flow_action *flow_action,
 			entry->police.burst = tcf_police_tcfp_burst(act);
 			entry->police.rate_bytes_ps =
 				tcf_police_rate_bytes_ps(act);
+			entry->police.mtu = tcf_police_tcfp_mtu(act);
 		} else if (is_tcf_ct(act)) {
 			entry->id = FLOW_ACTION_CT;
 			entry->ct.action = tcf_ct_action(act);