[PATCH 05/11] openvswitch: Add recirc action

@@ -291,6 +291,7 @@ enum ovs_key_attr {
 	OVS_KEY_ATTR_TCP_FLAGS,	/* be16 TCP flags. */
 	OVS_KEY_ATTR_DP_HASH,      /* u32 hash value. Value 0 indicates the hash
 				   is not computed by the datapath. */
+	OVS_KEY_ATTR_RECIRC_ID, /* u32 recirc id */
 
 #ifdef __KERNEL__
 	OVS_KEY_ATTR_IPV4_TUNNEL,  /* struct ovs_key_ipv4_tunnel */

@@ -544,6 +545,7 @@ enum ovs_action_attr {
 	OVS_ACTION_ATTR_PUSH_VLAN,    /* struct ovs_action_push_vlan. */
 	OVS_ACTION_ATTR_POP_VLAN,     /* No argument. */
 	OVS_ACTION_ATTR_SAMPLE,       /* Nested OVS_SAMPLE_ATTR_*. */
+	OVS_ACTION_ATTR_RECIRC,       /* u32 recirc_id. */
 	OVS_ACTION_ATTR_HASH,         /* struct ovs_action_hash. */
 	__OVS_ACTION_ATTR_MAX
 };

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007-2013 Nicira, Inc.
+ * Copyright (c) 2007-2014 Nicira, Inc.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public

@@ -520,6 +520,26 @@ static int execute_set_action(struct sk_buff *skb,
 	return err;
 }
 
+static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
+			  const struct nlattr *a)
+{
+	struct sw_flow_key recirc_key;
+	const struct vport *p = OVS_CB(skb)->input_vport;
+	uint32_t hash = OVS_CB(skb)->pkt_key->ovs_flow_hash;
+	int err;
+
+	err = ovs_flow_extract(skb, p->port_no, &recirc_key);
+	if (err)
+		return err;
+
+	recirc_key.ovs_flow_hash = hash;
+	recirc_key.recirc_id = nla_get_u32(a);
+
+	ovs_dp_process_packet_with_key(skb, &recirc_key);
+
+	return 0;
+}
+
 /* Execute a list of actions against 'skb'. */
 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 			const struct nlattr *attr, int len, bool keep_skb)

@@ -564,6 +584,30 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 			err = pop_vlan(skb);
 			break;
 
+		case OVS_ACTION_ATTR_RECIRC: {
+			struct sk_buff *recirc_skb;
+			const bool last_action = (a->nla_len == rem);
+
+			if (__this_cpu_read(net_xmit_recursion) > NET_RECURSION_LIMIT) {
+				net_crit_ratelimited("Net recursion limit readched\n");
+				break;
+			}
+
+			if (!last_action || keep_skb)
+				recirc_skb = skb_clone(skb, GFP_ATOMIC);
+			else
+				recirc_skb = skb;
+
+			__this_cpu_inc(net_xmit_recursion);
+			err = execute_recirc(dp, recirc_skb, a);
+			__this_cpu_dec(net_xmit_recursion);
+
+			if (last_action || err)
+				return err;
+
+			break;
+		}
+
 		case OVS_ACTION_ATTR_SET:
 			err = execute_set_action(skb, nla_data(a));
 			break;

@@ -238,33 +238,25 @@ void ovs_dp_detach_port(struct vport *p)
 	ovs_vport_del(p);
 }
 
-/* Must be called with rcu_read_lock. */
-void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
+void ovs_dp_process_packet_with_key(struct sk_buff *skb,
+				    struct sw_flow_key *pkt_key)
 {
+	const struct vport *p = OVS_CB(skb)->input_vport;
 	struct datapath *dp = p->dp;
 	struct sw_flow *flow;
 	struct dp_stats_percpu *stats;
-	struct sw_flow_key key;
 	u64 *stats_counter;
 	u32 n_mask_hit;
-	int error;
 
 	stats = this_cpu_ptr(dp->stats_percpu);
 
-	/* Extract flow from 'skb' into 'key'. */
-	error = ovs_flow_extract(skb, p->port_no, &key);
-	if (unlikely(error)) {
-		kfree_skb(skb);
-		return;
-	}
-
 	/* Look up flow. */
-	flow = ovs_flow_tbl_lookup_stats(&dp->table, &key, &n_mask_hit);
+	flow = ovs_flow_tbl_lookup_stats(&dp->table, pkt_key, &n_mask_hit);
 	if (unlikely(!flow)) {
 		struct dp_upcall_info upcall;
 
 		upcall.cmd = OVS_PACKET_CMD_MISS;
-		upcall.key = &key;
+		upcall.key = pkt_key;
 		upcall.userdata = NULL;
 		upcall.portid = ovs_vport_find_upcall_portid(p, skb);
 		ovs_dp_upcall(dp, skb, &upcall);

@@ -274,7 +266,7 @@ void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
 	}
 
 	OVS_CB(skb)->flow = flow;
-	OVS_CB(skb)->pkt_key = &key;
+	OVS_CB(skb)->pkt_key = pkt_key;
 
 	ovs_flow_stats_update(OVS_CB(skb)->flow, skb);
 	ovs_execute_actions(dp, skb);

@@ -288,6 +280,24 @@ out:
 	u64_stats_update_end(&stats->syncp);
 }
 
+/* Must be called with rcu_read_lock. */
+void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
+{
+	int error;
+	struct sw_flow_key key;
+
+	OVS_CB(skb)->input_vport = p;
+
+	/* Extract flow from 'skb' into 'key'. */
+	error = ovs_flow_extract(skb, p->port_no, &key);
+	if (unlikely(error)) {
+		kfree_skb(skb);
+		return;
+	}
+
+	ovs_dp_process_packet_with_key(skb, &key);
+}
+
 int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
 		  const struct dp_upcall_info *upcall_info)
 {

@@ -511,6 +521,7 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
 	struct sw_flow *flow;
 	struct datapath *dp;
 	struct ethhdr *eth;
+	struct vport *input_vport;
 	int len;
 	int err;
 

@@ -574,6 +585,15 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
 	if (!dp)
 		goto err_unlock;
 
+	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
+	if (!input_vport)
+		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
+
+	if (!input_vport)
+		goto err_unlock;
+
+	OVS_CB(packet)->input_vport = input_vport;
+
 	local_bh_disable();
 	err = ovs_execute_actions(dp, packet);
 	local_bh_enable();

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007-2012 Nicira, Inc.
+ * Copyright (c) 2007-2014 Nicira, Inc.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public

@@ -97,12 +97,14 @@ struct datapath {
  * @flow: The flow associated with this packet.  May be %NULL if no flow.
  * @pkt_key: The flow information extracted from the packet.  Must be nonnull.
  * @tun_key: Key for the tunnel that encapsulated this packet. NULL if the
- * packet is not being tunneled.
+ * @input_vport: The original vport packet came in on. This value is cached
+ * when a packet is received by OVS.
  */
 struct ovs_skb_cb {
 	struct sw_flow		*flow;
 	struct sw_flow_key	*pkt_key;
 	struct ovs_key_ipv4_tunnel  *tun_key;
+	struct vport	*input_vport;
 };
 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb)
 

@@ -184,6 +186,8 @@ extern struct notifier_block ovs_dp_device_notifier;
 extern struct genl_family dp_vport_genl_family;
 
 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *);
+void ovs_dp_process_packet_with_key(struct sk_buff *,
+				    struct sw_flow_key *pkt_key);
 void ovs_dp_detach_port(struct vport *);
 int ovs_dp_upcall(struct datapath *, struct sk_buff *,
 		  const struct dp_upcall_info *);

@@ -73,6 +73,7 @@ struct sw_flow_key {
 		u16	in_port;	/* Input switch port (or DP_MAX_PORTS). */
 	} __packed phy; /* Safe when right after 'tun_key'. */
 	u32 ovs_flow_hash;		/* Datapath computed hash value.  */
+	u32 recirc_id;			/* Recirculation ID.  */
 	struct {
 		u8     src[ETH_ALEN];	/* Ethernet source address. */
 		u8     dst[ETH_ALEN];	/* Ethernet destination address. */

@@ -252,6 +252,7 @@ static const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 	[OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 	[OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 	[OVS_KEY_ATTR_DP_HASH] = sizeof(u32),
+	[OVS_KEY_ATTR_RECIRC_ID] = sizeof(u32),
 	[OVS_KEY_ATTR_TUNNEL] = -1,
 };
 

@@ -462,6 +463,13 @@ static int metadata_from_nlattrs(struct sw_flow_match *match,  u64 *attrs,
 		*attrs &= ~(1 << OVS_KEY_ATTR_DP_HASH);
 	}
 
+	if (*attrs & (1 << OVS_KEY_ATTR_RECIRC_ID)) {
+		u32 recirc_id = nla_get_u32(a[OVS_KEY_ATTR_RECIRC_ID]);
+
+		SW_FLOW_KEY_PUT(match, recirc_id, recirc_id, is_mask);
+		*attrs &= ~(1 << OVS_KEY_ATTR_RECIRC_ID);
+	}
+
 	if (*attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
 		SW_FLOW_KEY_PUT(match, phy.priority,
 			  nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]), is_mask);

@@ -867,6 +875,7 @@ int ovs_nla_get_flow_metadata(struct sw_flow *flow,
 	flow->key.phy.priority = 0;
 	flow->key.phy.skb_mark = 0;
 	flow->key.ovs_flow_hash = 0;
+	flow->key.recirc_id = 0;
 	memset(tun_key, 0, sizeof(flow->key.tun_key));
 
 	err = parse_flow_nlattrs(attr, a, &attrs);

@@ -893,6 +902,9 @@ int ovs_nla_put_flow(const struct sw_flow_key *swkey,
 	if (nla_put_u32(skb, OVS_KEY_ATTR_DP_HASH, output->ovs_flow_hash))
 		goto nla_put_failure;
 
+	if (nla_put_u32(skb, OVS_KEY_ATTR_RECIRC_ID, output->recirc_id))
+		goto nla_put_failure;
+
 	if (nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, output->phy.priority))
 		goto nla_put_failure;
 

@@ -1421,6 +1433,7 @@ int ovs_nla_copy_actions(const struct nlattr *attr,
 		/* Expected argument lengths, (u32)-1 for variable length. */
 		static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = {
 			[OVS_ACTION_ATTR_OUTPUT] = sizeof(u32),
+			[OVS_ACTION_ATTR_RECIRC] = sizeof(u32),
 			[OVS_ACTION_ATTR_USERSPACE] = (u32)-1,
 			[OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan),
 			[OVS_ACTION_ATTR_POP_VLAN] = 0,

@@ -1477,6 +1490,9 @@ int ovs_nla_copy_actions(const struct nlattr *attr,
 				return -EINVAL;
 			break;
 
+		case OVS_ACTION_ATTR_RECIRC:
+			break;
+
 		case OVS_ACTION_ATTR_SET:
 			err = validate_set(a, key, sfa, &skip_copy);
 			if (err)