core/pktfwd_controller.py

   1 # Copyright 2016 Intel Corporation.
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #   http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 """Packet forwarder controller for Physical to Physical deployment
  16 """
  17
  18 import logging
  19 from conf import settings
  20
  21 class PktFwdController(object):
  22     """Packet forwarder controller for P2P deployment scenario.
  23
  24     Attributes:
  25         _pktfwd_class: The packet forwarder class to be used.
  26         _pktfwd: The packet forwarder object controlled by this controller
  27     """
  28     def __init__(self, deployment, pktfwd_class):
  29         """Initializes up the prerequisites for the P2P deployment scenario.
  30
  31         :vswitch_class: the vSwitch class to be used.
  32         """
  33         self._deployment = deployment
  34         self._logger = logging.getLogger(__name__)
  35         self._pktfwd_class = pktfwd_class
  36         self._pktfwd = pktfwd_class(guest=True if deployment == "pvp" and
  37                                     settings.getValue('VNF') != "QemuPciPassthrough" else False)
  38         self._logger.debug('Creation using ' + str(self._pktfwd_class))
  39
  40     def setup(self):
  41         """Sets up the packet forwarder for p2p.
  42         """
  43         self._logger.debug('Setup using ' + str(self._pktfwd_class))
  44
  45         try:
  46             self._pktfwd.start()
  47         except:
  48             self._pktfwd.stop()
  49             raise
  50
  51     def get_vswitch(self):
  52         """See IVswitchController for description
  53         """
  54         return self._pktfwd
  55
  56     def setup_for_guest(self):
  57         """Sets up the packet forwarder for pvp.
  58         """
  59         self._logger.debug('Setup using ' + str(self._pktfwd_class))
  60
  61         try:
  62             self._pktfwd.start_for_guest()
  63         except:
  64             self._pktfwd.stop()
  65             raise
  66
  67     def stop(self):
  68         """Tears down the packet forwarder created in setup().
  69         """
  70         self._logger.debug('Stop using ' + str(self._pktfwd_class))
  71         self._pktfwd.stop()
  72
  73     def __enter__(self):
  74         if self._deployment.find("p2p") == 0:
  75             self.setup()
  76         elif self._deployment == "pvp" and settings.getValue('VNF') != "QemuPciPassthrough":
  77             self.setup_for_guest()
  78
  79     def __exit__(self, type_, value, traceback):
  80         if self._deployment.find("p2p") == 0:
  81             self.stop()
  82         elif self._deployment == "pvp" and settings.getValue('VNF') != "QemuPciPassthrough":
  83             self.stop()
  84
  85     def get_pktfwd(self):
  86         """Get the controlled packet forwarder
  87
  88         :return: The controlled IPktFwd
  89         """
  90         return self._pktfwd
  91
  92     def dump_vswitch_flows(self):
  93         """ Dumps flows from vswitch
  94         """
  95         raise NotImplementedError(
  96             "The PktFwdController does not implement the "
  97             "\"dump_vswitch_flows\" function.")