Add interprocess locks to net interfaces handlers

Manila uses one service network for all backends, in this case
handling of all shared net resources should be covered with locks
in network modules.

Changes:
- added decorator 'device_name_synchronized' to remove concurrency
  issues.
- changed arg positions in related methods to satisfy requirement of
  decorator.
- with change of arg position was removed arg 'network_id' in
  metaclass 'LinuxInterfaceDriver' as redundant.

Change-Id: I7468f0a85bbc2752cfd82ae85d7491636ddea24b
Closes-Bug: #1346796

manila/network/linux/interface.py

@@ -22,6 +22,7 @@ import six
 from manila import exception
 from manila.network.linux import ip_lib
 from manila.network.linux import ovs_lib
+from manila.openstack.common import lockutils
 from manila.openstack.common import log as logging
 from manila import utils
 
@@ -38,6 +39,22 @@ CONF = cfg.CONF
 CONF.register_opts(OPTS)
 
 
+def device_name_synchronized(f):
+    """Wraps methods with interprocess locks by device names."""
+
+    def wrapped_func(self, *args, **kwargs):
+        device_name = "device_name_%s" % args[0]
+
+        @lockutils.synchronized(device_name, external=True,
+                                lock_path="service_instance_locks")
+        def source_func(self, *args, **kwargs):
+            return f(self, *args, **kwargs)
+
+        return source_func(self, *args, **kwargs)
+
+    return wrapped_func
+
+
 @six.add_metaclass(abc.ABCMeta)
 class LinuxInterfaceDriver(object):
 
@@ -48,6 +65,7 @@ class LinuxInterfaceDriver(object):
     def __init__(self):
         self.conf = CONF
 
+    @device_name_synchronized
     def init_l3(self, device_name, ip_cidrs, namespace=None):
         """Set the L3 settings for the interface using data from the port.
 
@@ -82,7 +100,7 @@ class LinuxInterfaceDriver(object):
         return (self.DEV_NAME_PREFIX + port['id'])[:self.DEV_NAME_LEN]
 
     @abc.abstractmethod
-    def plug(self, network_id, port_id, device_name, mac_address,
+    def plug(self, device_name, port_id, mac_address,
              bridge=None, namespace=None, prefix=None):
         """Plug in the interface."""
 
@@ -113,7 +131,8 @@ class OVSInterfaceDriver(LinuxInterfaceDriver):
                 'external-ids:attached-mac=%s' % mac_address]
         utils.execute(*cmd, run_as_root=True)
 
-    def plug(self, port_id, device_name, mac_address,
+    @device_name_synchronized
+    def plug(self, device_name, port_id, mac_address,
              bridge=None, namespace=None, prefix=None):
         """Plug in the interface."""
         if not bridge:
@@ -139,6 +158,7 @@ class OVSInterfaceDriver(LinuxInterfaceDriver):
             LOG.warn(_("Device %s already exists"), device_name)
         ns_dev.link.set_up()
 
+    @device_name_synchronized
     def unplug(self, device_name, bridge=None, namespace=None, prefix=None):
         """Unplug the interface."""
         if not bridge:
@@ -160,7 +180,8 @@ class BridgeInterfaceDriver(LinuxInterfaceDriver):
 
     DEV_NAME_PREFIX = 'ns-'
 
-    def plug(self, port_id, device_name, mac_address,
+    @device_name_synchronized
+    def plug(self, device_name, port_id, mac_address,
              bridge=None, namespace=None, prefix=None):
         """Plugin the interface."""
         ip = ip_lib.IPWrapper()
@@ -184,6 +205,7 @@ class BridgeInterfaceDriver(LinuxInterfaceDriver):
         root_veth.link.set_up()
         ns_veth.link.set_up()
 
+    @device_name_synchronized
     def unplug(self, device_name, bridge=None, namespace=None, prefix=None):
         """Unplug the interface."""
         device = ip_lib.IPDevice(device_name, namespace)

manila/share/drivers/service_instance.py

@@ -500,7 +500,7 @@ class ServiceInstanceManager(object):
         port = self._get_service_port()
         port = self._add_fixed_ips_to_service_port(port)
         interface_name = self.vif_driver.get_device_name(port)
-        self.vif_driver.plug(port['id'], interface_name, port['mac_address'])
+        self.vif_driver.plug(interface_name, port['id'], port['mac_address'])
         ip_cidrs = []
         for fixed_ip in port['fixed_ips']:
             subnet = self.neutron_api.get_subnet(fixed_ip['subnet_id'])

manila/tests/network/linux/test_interface.py

@@ -139,8 +139,8 @@ class TestOVSInterfaceDriver(TestBase):
         with mock.patch.object(utils, 'execute') as execute:
             ovs = interface.OVSInterfaceDriver()
             self.device_exists.side_effect = device_exists
-            ovs.plug('port-1234',
-                     'tap0',
+            ovs.plug('tap0',
+                     'port-1234',
                      'aa:bb:cc:dd:ee:ff',
                      bridge=bridge,
                      namespace=namespace)
@@ -193,8 +193,8 @@ class TestBridgeInterfaceDriver(TestBase):
         self.device_exists.side_effect = device_exists
         br = interface.BridgeInterfaceDriver()
         mac_address = 'aa:bb:cc:dd:ee:ff'
-        br.plug('port-1234',
-                'ns-0',
+        br.plug('ns-0',
+                'port-1234',
                 mac_address,
                 namespace=namespace)
 

manila/tests/test_service_instance.py

@@ -668,7 +668,7 @@ class ServiceInstanceManagerTestCase(test.TestCase):
         self._manager.vif_driver.get_device_name.assert_called_once_with(
                 fake_port)
         self._manager.vif_driver.plug.assert_called_once_with(
-            fake_port['id'], interface_name, fake_port['mac_address'])
+            interface_name, fake_port['id'], fake_port['mac_address'])
         self._manager.neutron_api.get_subnet.assert_called_once_with(
             fake_subnet['id'])
         self._manager.vif_driver.init_l3.assert_called_once_with(