Use ovs db notification to update metadata flows

This patch will use the notification from ovs db to update/delete
the OpenFlows for metadata service. So that when metadata proxy
restarts, the latest information can be upadted in OpenFlow. And thus,
the vm can still use metadata even if the metadata proxy restarts.

Change-Id: Idaf3060d80a95b210ca4934bd9b3ab29a7c6fe5a
Closes-bug: #1613615

devstack/plugin.sh

@@ -137,7 +137,7 @@ function configure_df_metadata_service {
         iniset $NEUTRON_CONF DEFAULT metadata_proxy_shared_secret $METADATA_PROXY_SHARED_SECRET
         iniset $NEUTRON_CONF df_metadata ip "$DF_METADATA_SERVICE_IP"
         iniset $NEUTRON_CONF df_metadata port "$DF_METADATA_SERVICE_PORT"
-        iniset $NEUTRON_CONF df_metadata interface "$DF_METADATA_SERVICE_INTERFACE"
+        iniset $NEUTRON_CONF df metadata_interface "$DF_METADATA_SERVICE_INTERFACE"
     fi
 }
 

dragonflow/cmd/eventlet/df_metadata_service.py

@@ -11,24 +11,33 @@
 #    under the License.
 
 from oslo_config import cfg
+from oslo_log import log
 
 from neutron.agent.common import utils
+from neutron.agent.linux import ip_lib
 from neutron.agent.metadata import config as metadata_conf
 from neutron.common import config
 from neutron import wsgi
 
+from dragonflow._i18n import _LI
 from dragonflow.common import common_params
 from dragonflow.controller import metadata_service_app
 
 import sys
 
 
+LOG = log.getLogger(__name__)
+
 METADATA_ROUTE_TABLE_ID = '2'
 
 
 def environment_setup():
     bridge = cfg.CONF.df.integration_bridge
-    interface = cfg.CONF.df_metadata.interface
+    interface = cfg.CONF.df.metadata_interface
+    if ip_lib.device_exists(interface):
+        LOG.info(_LI("Device %s already exists"), interface)
+        return
+
     cmd = ["ovs-vsctl", "add-port", bridge, interface,
         "--", "set", "Interface", interface, "type=internal"]
     utils.execute(cmd, run_as_root=True)
@@ -50,7 +59,7 @@ def environment_setup():
 
 def environment_destroy():
     bridge = cfg.CONF.df.integration_bridge
-    interface = cfg.CONF.df_metadata.interface
+    interface = cfg.CONF.df.metadata_interface
     cmd = ["ovs-vsctl", "del-port", bridge, interface]
     utils.execute(cmd, run_as_root=True, check_exit_code=[0])
 

dragonflow/common/common_params.py

@@ -132,5 +132,10 @@ df_opts = [
     cfg.StrOpt("vhost_sock_dir",
                default="/var/run/openvswitch",
                help=_("The directory in which vhost virtio socket"
-                      "is created by all the vswitch daemons"))
+                      "is created by all the vswitch daemons")),
+    cfg.StrOpt(
+        'metadata_interface',
+        default='tap-metadata',
+        help=_('The name of the interface to bind the metadata service proxy'),
+    )
 ]

dragonflow/controller/df_local_controller.py

@@ -544,10 +544,12 @@ class DfLocalController(object):
                 self._associate_floatingip(new_floatingip)
 
     def ovs_port_updated(self, ovs_port):
+        self.open_flow_app.notify_ovs_port_updated(ovs_port)
         self.topology.ovs_port_updated(ovs_port)
 
-    def ovs_port_deleted(self, ovs_port_id):
-        self.topology.ovs_port_deleted(ovs_port_id)
+    def ovs_port_deleted(self, ovs_port):
+        self.open_flow_app.notify_ovs_port_deleted(ovs_port)
+        self.topology.ovs_port_deleted(ovs_port.get_id())
 
     def ovs_sync_finished(self):
         self.open_flow_app.notify_ovs_sync_finished()

dragonflow/controller/metadata_service_app.py

@@ -23,7 +23,6 @@ import webob
 
 from oslo_config import cfg
 from oslo_log import log
-from oslo_service import loopingcall
 from oslo_utils import encodeutils
 
 from neutron.agent.ovsdb.native import idlutils
@@ -64,11 +63,6 @@ options = [
         default='18080',
         help=_('The port to which the DF metadata service proxy is bound'),
     ),
-    cfg.StrOpt(
-        'interface',
-        default='tap-metadata',
-        help=_('The name of the interface to bind the metadata service proxy'),
-    ),
 ]
 
 
@@ -85,17 +79,39 @@ class MetadataServiceApp(df_base_app.DFlowApp):
         cfg.CONF.register_opts(options, group='df_metadata')
         self._ip = cfg.CONF.df_metadata.ip
         self._port = cfg.CONF.df_metadata.port
-        self._interface = cfg.CONF.df_metadata.interface
+        self._interface = cfg.CONF.df.metadata_interface
 
-    def ovs_sync_started(self):
-        self.initialize()
+    def ovs_port_updated(self, ovs_port):
+        if ovs_port.get_name() != cfg.CONF.df.metadata_interface:
+            return
 
-    def initialize(self):
-        loopingcall.FixedIntervalLoopingCall(
-            self._wait_for_tap_metadata_interface
-        ).start(0, 1)
+        self._add_metadata_interface_flows()
 
-    def _wait_for_tap_metadata_interface(self):
+    def ovs_port_deleted(self, ovs_port):
+        if ovs_port.get_name() != cfg.CONF.df.metadata_interface:
+            return
+
+        self._remove_metadata_interface_flows()
+
+    def _remove_metadata_interface_flows(self):
+        if not self._ofport:
+            return
+
+        parser = self.get_datapath().ofproto_parser
+        ofproto = self.get_datapath().ofproto
+
+        self.mod_flow(
+            datapath=self.get_datapath(),
+            table_id=const.INGRESS_CLASSIFICATION_DISPATCH_TABLE,
+            command=ofproto.OFPFC_DELETE,
+            priority=const.PRIORITY_MEDIUM,
+            out_port=ofproto.OFPP_ANY,
+            out_group=ofproto.OFPG_ANY,
+            match=parser.OFPMatch(in_port=self._ofport))
+
+        self._ofport = None
+
+    def _add_metadata_interface_flows(self):
         idl = self.vswitch_api.idl
         if not idl:
             return
@@ -116,7 +132,6 @@ class MetadataServiceApp(df_base_app.DFlowApp):
         if ofport <= 0:
             return
         self._add_tap_metadata_port(ofport, interface.mac_in_use[0])
-        raise loopingcall.LoopingCallDone()
 
     def _add_tap_metadata_port(self, ofport, mac):
         """

dragonflow/controller/ryu_base_app.py

@@ -133,6 +133,12 @@ class RyuDFAdapter(OFPHandler):
     def notify_ovs_sync_started(self):
         self.dispatcher.dispatch('ovs_sync_started')
 
+    def notify_ovs_port_updated(self, ovs_port):
+        self.dispatcher.dispatch('ovs_port_updated', ovs_port)
+
+    def notify_ovs_port_deleted(self, ovs_port):
+        self.dispatcher.dispatch('ovs_port_deleted', ovs_port)
+
     def notify_associate_floatingip(self, floatingip):
         self.dispatcher.dispatch('associate_floatingip', floatingip)
 

dragonflow/db/api_nb.py

@@ -259,8 +259,8 @@ class NbApi(object):
             elif action == 'sync_started':
                 self.controller.ovs_sync_started()
             elif action == 'delete':
-                ovs_port_id = key
-                self.controller.ovs_port_deleted(ovs_port_id)
+                ovs_port = OvsPort(value)
+                self.controller.ovs_port_deleted(ovs_port)
         elif 'log' == action:
             message = _LI(
                 'Log event (Info): '

dragonflow/db/drivers/ovsdb_vswitch_impl.py

@@ -419,6 +419,8 @@ class OvsdbMonitor(object):
                               constants.OVS_BRIDGE_INTERFACE)
 
     def _is_handle_interface_update(self, interface):
+        if interface.name == cfg.CONF.df.metadata_interface:
+            return True
         if interface.type not in self.interface_type:
             return False
         if interface.name.startswith('qg'):