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>

1 files changed, 26 insertions, 0 deletions

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index a794d1dd7b40..f7fc507d82ab 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -289,6 +289,9 @@ enum ovs_key_attr {
         OVS_KEY_ATTR_TUNNEL,    /* Nested set of ovs_tunnel attributes */
         OVS_KEY_ATTR_SCTP,      /* struct ovs_key_sctp */
         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 */
@@ -493,6 +496,27 @@ struct ovs_action_push_vlan {
         __be16 vlan_tci;        /* 802.1Q TCI (VLAN ID and priority). */
 };
 
+/* Data path hash algorithm for computing Datapath hash.
+ *
+ * The algorithm type only specifies the fields in a flow
+ * will be used as part of the hash. Each datapath is free
+ * to use its own hash algorithm. The hash value will be
+ * opaque to the user space daemon.
+ */
+enum ovs_hash_alg {
+        OVS_HASH_ALG_L4,
+};
+
+/*
+ * struct ovs_action_hash - %OVS_ACTION_ATTR_HASH action argument.
+ * @hash_alg: Algorithm used to compute hash prior to recirculation.
+ * @hash_basis: basis used for computing hash.
+ */
+struct ovs_action_hash {
+        uint32_t  hash_alg;     /* One of ovs_hash_alg. */
+        uint32_t  hash_basis;
+};
+
 /**
  * enum ovs_action_attr - Action types.
  *
@@ -521,6 +545,8 @@ 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
 };