From 8ff25e725e148acf83ef6e1f6a3c445da00e3932 Mon Sep 17 00:00:00 2001
From: Moshe Levi <moshele@mellanox.com>
Date: Mon, 4 Jan 2016 11:14:58 +0200
Subject: [PATCH] hardware offload support for openvswitch

In Kernel 4.8 we introduced Traffic Control (TC see [1]) hardware offloads
framework for SR-IOV VFs which allows us to configure the NIC [2].
Subsequent OVS patches [3] allow us to use the TC framework
to offload OVS datapath rules.

This patch allow OVS mech driver to bind direct (SR-IOV) port.
This will allow to offload the OVS flows using tc to the SR-IOV NIC
and gain accelerate OVS.

[1] https://linux.die.net/man/8/tc
[2] http://netdevconf.org/1.2/papers/efraim-gerlitz-sriov-ovs-final.pdf
[3] https://mail.openvswitch.org/pipermail/ovs-dev/2017-April/330606.html

DocImpact: Add SR-IOV offload support for OVS mech driver
Partial-Bug: #1627987
Depends-On: I6bc2539a1ddbf7990164abeb8bb951ddcb45c993

Change-Id: I77650be5f04775a72e2bdf694f93988825a84b72
---
 .../openvswitch/mech_driver/mech_openvswitch.py     |  8 +++++++-
 .../mech_driver/test_mech_openvswitch.py            | 13 +++++++++++++
 ...s_hardware_offload_support-798d3896ab2c4b1d.yaml |  7 +++++++
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 releasenotes/notes/ovs_hardware_offload_support-798d3896ab2c4b1d.yaml

diff --git a/neutron/plugins/ml2/drivers/openvswitch/mech_driver/mech_openvswitch.py b/neutron/plugins/ml2/drivers/openvswitch/mech_driver/mech_openvswitch.py
index 30ef4c8e882..afacb7da7e1 100644
--- a/neutron/plugins/ml2/drivers/openvswitch/mech_driver/mech_openvswitch.py
+++ b/neutron/plugins/ml2/drivers/openvswitch/mech_driver/mech_openvswitch.py
@@ -50,10 +50,16 @@ class OpenvswitchMechanismDriver(mech_agent.SimpleAgentMechanismDriverBase):
                 IPTABLES_FW_DRIVER_FULL, 'iptables_hybrid')) and sg_enabled
         vif_details = {portbindings.CAP_PORT_FILTER: sg_enabled,
                        portbindings.OVS_HYBRID_PLUG: hybrid_plug_required}
+        # NOTE(moshele): Bind DIRECT (SR-IOV) port allows
+        # to offload the OVS flows using tc to the SR-IOV NIC.
+        # We are using OVS mechanism driver because the openvswitch (>=2.8.0)
+        # support hardware offload via tc and that allow us to manage the VF by
+        # OpenFlow control plane using representor net-device.
         super(OpenvswitchMechanismDriver, self).__init__(
             constants.AGENT_TYPE_OVS,
             portbindings.VIF_TYPE_OVS,
-            vif_details)
+            vif_details, supported_vnic_types=[portbindings.VNIC_NORMAL,
+                                               portbindings.VNIC_DIRECT])
         ovs_qos_driver.register()
 
     def get_allowed_network_types(self, agent):
diff --git a/neutron/tests/unit/plugins/ml2/drivers/openvswitch/mech_driver/test_mech_openvswitch.py b/neutron/tests/unit/plugins/ml2/drivers/openvswitch/mech_driver/test_mech_openvswitch.py
index ff22690252e..9e21316b938 100644
--- a/neutron/tests/unit/plugins/ml2/drivers/openvswitch/mech_driver/test_mech_openvswitch.py
+++ b/neutron/tests/unit/plugins/ml2/drivers/openvswitch/mech_driver/test_mech_openvswitch.py
@@ -236,3 +236,16 @@ class OpenvswitchMechanismDPDKTestCase(OpenvswitchMechanismBaseTestCase):
 
         result = self.driver.get_vif_type(None, self.AGENT_SYSTEM, None)
         self.assertEqual(portbindings.VIF_TYPE_OVS, result)
+
+
+class OpenvswitchMechanismSRIOVTestCase(OpenvswitchMechanismBaseTestCase):
+
+    def _make_port_ctx(self, agents):
+        segments = [{api.ID: 'local_segment_id', api.NETWORK_TYPE: 'local'}]
+        return base.FakePortContext(self.AGENT_TYPE, agents, segments,
+                                    vnic_type=portbindings.VNIC_DIRECT)
+
+    def test_get_vif_type(self):
+        context = self._make_port_ctx(self.AGENTS)
+        result = self.driver.get_vif_type(context, self.AGENTS[0], None)
+        self.assertEqual(self.VIF_TYPE, result)
diff --git a/releasenotes/notes/ovs_hardware_offload_support-798d3896ab2c4b1d.yaml b/releasenotes/notes/ovs_hardware_offload_support-798d3896ab2c4b1d.yaml
new file mode 100644
index 00000000000..287afb22f9c
--- /dev/null
+++ b/releasenotes/notes/ovs_hardware_offload_support-798d3896ab2c4b1d.yaml
@@ -0,0 +1,7 @@
+---
+prelude: >
+    The ``openvswitch`` mechanism driver now supports hardware offload via SR-IOV.
+features:
+  - The ``openvswitch`` mechanism driver now allows binding direct (SR-IOV) ports.
+    Using ``openvswitch`` 2.8.0 and 'Linux Kernel' 4.8 allows to control the SR-IOV VF
+    via OpenFlow control plane and gain accelerated 'Open vSwitch'.
\ No newline at end of file