Inherit from neutron-lib "LinuxInterfaceDriver" class

"LinuxInterfaceDriver" methods "plug_new" and "unplug" are implemented
in other projects than Neutron. In order to avoid method signature
changes that could affect to those projects implementing this class,
the base metaclass is now in neutron-lib.

Change-Id: I2ce790b8796c3aa65c771d765a20938e8d56c0bc

neutron/agent/linux/interface.py

@@ -17,6 +17,7 @@ import abc
 import time
 
 import netaddr
+from neutron_lib.agent.linux import interface
 from neutron_lib import constants
 from neutron_lib import exceptions
 from oslo_log import log as logging
@@ -40,10 +41,8 @@ def _get_veth(name1, name2, namespace2):
             ip_lib.IPDevice(name2, namespace=namespace2))
 
 
-class LinuxInterfaceDriver(object, metaclass=abc.ABCMeta):
-
-    DEV_NAME_LEN = constants.LINUX_DEV_LEN
-    DEV_NAME_PREFIX = constants.TAP_DEVICE_PREFIX
+class LinuxInterfaceDriver(interface.LinuxInterfaceDriver,
+                           metaclass=abc.ABCMeta):
 
     def __init__(self, conf, **kwargs):
         self.conf = conf
@@ -257,12 +256,6 @@ class LinuxInterfaceDriver(object, metaclass=abc.ABCMeta):
                {'dev': dev_name, 'enabled': int(enabled)}]
         ip_lib.sysctl(cmd, namespace=namespace)
 
-    @abc.abstractmethod
-    def plug_new(self, network_id, port_id, device_name, mac_address,
-                 bridge=None, namespace=None, prefix=None, mtu=None,
-                 link_up=True):
-        """Plug in the interface only for new devices that don't exist yet."""
-
     def plug(self, network_id, port_id, device_name, mac_address,
              bridge=None, namespace=None, prefix=None, mtu=None, link_up=True):
         if not ip_lib.device_exists(device_name,
@@ -277,10 +270,6 @@ class LinuxInterfaceDriver(object, metaclass=abc.ABCMeta):
             else:
                 LOG.warning("No MTU configured for port %s", port_id)
 
-    @abc.abstractmethod
-    def unplug(self, device_name, bridge=None, namespace=None, prefix=None):
-        """Unplug the interface."""
-
     @property
     def bridged(self):
         """Whether the DHCP port is bridged to the VM TAP interfaces.