openvswitch: Add meter infrastructure

OVS kernel datapath so far does not support Openflow meter action.
This is the first stab at adding kernel datapath meter support.
This implementation supports only drop band type.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/openvswitch/Makefile

@@ -12,6 +12,7 @@ openvswitch-y := \
 	flow.o \
 	flow_netlink.o \
 	flow_table.o \
+	meter.o \
 	vport.o \
 	vport-internal_dev.o \
 	vport-netdev.o

net/openvswitch/datapath.c

@@ -55,6 +55,7 @@
 #include "flow.h"
 #include "flow_table.h"
 #include "flow_netlink.h"
+#include "meter.h"
 #include "vport-internal_dev.h"
 #include "vport-netdev.h"
 
@@ -174,6 +175,7 @@ static void destroy_dp_rcu(struct rcu_head *rcu)
 	ovs_flow_tbl_destroy(&dp->table);
 	free_percpu(dp->stats_percpu);
 	kfree(dp->ports);
+	ovs_meters_exit(dp);
 	kfree(dp);
 }
 
@@ -1572,6 +1574,10 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
 		INIT_HLIST_HEAD(&dp->ports[i]);
 
+	err = ovs_meters_init(dp);
+	if (err)
+		goto err_destroy_ports_array;
+
 	/* Set up our datapath device. */
 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
 	parms.type = OVS_VPORT_TYPE_INTERNAL;
@@ -1600,7 +1606,7 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 				ovs_dp_reset_user_features(skb, info);
 		}
 
-		goto err_destroy_ports_array;
+		goto err_destroy_meters;
 	}
 
 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
@@ -1615,8 +1621,10 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	ovs_notify(&dp_datapath_genl_family, reply, info);
 	return 0;
 
-err_destroy_ports_array:
+err_destroy_meters:
 	ovs_unlock();
+	ovs_meters_exit(dp);
+err_destroy_ports_array:
 	kfree(dp->ports);
 err_destroy_percpu:
 	free_percpu(dp->stats_percpu);
@@ -2265,6 +2273,7 @@ static struct genl_family * const dp_genl_families[] = {
 	&dp_vport_genl_family,
 	&dp_flow_genl_family,
 	&dp_packet_genl_family,
+	&dp_meter_genl_family,
 };
 
 static void dp_unregister_genl(int n_families)
@@ -2445,3 +2454,4 @@ MODULE_ALIAS_GENL_FAMILY(OVS_DATAPATH_FAMILY);
 MODULE_ALIAS_GENL_FAMILY(OVS_VPORT_FAMILY);
 MODULE_ALIAS_GENL_FAMILY(OVS_FLOW_FAMILY);
 MODULE_ALIAS_GENL_FAMILY(OVS_PACKET_FAMILY);
+MODULE_ALIAS_GENL_FAMILY(OVS_METER_FAMILY);

net/openvswitch/datapath.h

@@ -92,6 +92,9 @@ struct datapath {
 	u32 user_features;
 
 	u32 max_headroom;
+
+	/* Switch meters. */
+	struct hlist_head *meters;
 };
 
 /**