openvswitch: Add recirc and hash action.

Recirc action allows a packet to reenter openvswitch processing.
currently openvswitch lookup flow for packet received and execute
set of actions on that packet, with help of recirc action we can
process/modify the packet and recirculate it back in openvswitch
for another pass.

OVS hash action calculates 5-tupple hash and set hash in flow-key
hash. This can be used along with recirculation for distributing
packets among different ports for bond devices.
For example:
OVS bonding can use following actions:
Match on: bond flow; Action: hash, recirc(id)
Match on: recirc-id == id and hash lower bits == a;
          Action: output port_bond_a

Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c
index 630b320..f4c8daa 100644
--- a/net/openvswitch/flow_netlink.c
+++ b/net/openvswitch/flow_netlink.c
@@ -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
@@ -251,6 +251,8 @@
 	[OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 	[OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 	[OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
+	[OVS_KEY_ATTR_RECIRC_ID] = sizeof(u32),
+	[OVS_KEY_ATTR_DP_HASH] = sizeof(u32),
 	[OVS_KEY_ATTR_TUNNEL] = -1,
 };
 
@@ -454,6 +456,20 @@
 static int metadata_from_nlattrs(struct sw_flow_match *match,  u64 *attrs,
 				 const struct nlattr **a, bool is_mask)
 {
+	if (*attrs & (1 << OVS_KEY_ATTR_DP_HASH)) {
+		u32 hash_val = nla_get_u32(a[OVS_KEY_ATTR_DP_HASH]);
+
+		SW_FLOW_KEY_PUT(match, ovs_flow_hash, hash_val, is_mask);
+		*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);
@@ -873,6 +889,12 @@
 	struct nlattr *nla, *encap;
 	bool is_mask = (swkey != output);
 
+	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_DP_HASH, output->ovs_flow_hash))
+		goto nla_put_failure;
+
 	if (nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, output->phy.priority))
 		goto nla_put_failure;
 
@@ -1401,11 +1423,13 @@
 		/* 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,
 			[OVS_ACTION_ATTR_SET] = (u32)-1,
-			[OVS_ACTION_ATTR_SAMPLE] = (u32)-1
+			[OVS_ACTION_ATTR_SAMPLE] = (u32)-1,
+			[OVS_ACTION_ATTR_HASH] = sizeof(struct ovs_action_hash)
 		};
 		const struct ovs_action_push_vlan *vlan;
 		int type = nla_type(a);
@@ -1432,6 +1456,18 @@
 				return -EINVAL;
 			break;
 
+		case OVS_ACTION_ATTR_HASH: {
+			const struct ovs_action_hash *act_hash = nla_data(a);
+
+			switch (act_hash->hash_alg) {
+			case OVS_HASH_ALG_L4:
+				break;
+			default:
+				return  -EINVAL;
+			}
+
+			break;
+		}
 
 		case OVS_ACTION_ATTR_POP_VLAN:
 			break;
@@ -1444,6 +1480,9 @@
 				return -EINVAL;
 			break;
 
+		case OVS_ACTION_ATTR_RECIRC:
+			break;
+
 		case OVS_ACTION_ATTR_SET:
 			err = validate_set(a, key, sfa, &skip_copy);
 			if (err)