cinder/cinder/volume/targets/driver.py
Mitsuhiro Tanino fb8bfea97b Refactoring for export functions in Target object
Currently, export functions such as create_export() are implemented
in individual Target code, but most of them are same and these are
common features in each target.
This patch moves these methods to parent ISCSITarget class to
commonalize and each Target simply inherit these methods from parent
class. As a result of this change, LioAdm can inherit ISCSITarget
class directly instead of inheriting TgtAdm class.
This simplifies dependency of targets and improves maintainability.

By refactoring these methods, this patch also fixes following issues.

(a) Fix bug #1410566
After transitioning to the new driver and target model, iscsi_targets
is not added to the table during create_export() phase.
However, remove_export() in LIO Target is still reffering empty
iscsi_targets table. This causes NotFound exception and remove_export()
skips to do remove_iscsi_target().
As a result, iscsi target is not removed and the target continues to
grab the volume(logical volume) as an in-use status.
This patch fix the problem.

(b) Re-export a volume with CHAP
Current Tgt Target recreate iscsi target without CHAP during
ensure_export() even if the volume is exported with CHAP previously.
This patch changes this bahaviour to recreate iscsi target using
previous CHAP which is stored in volume file on state_path dir.

Closes-Bug: 1410566
Change-Id: Iea3d94e35a4ced4dafc1b61e2df6b075cf200577
2015-02-12 19:25:31 -07:00

70 lines
2.2 KiB
Python

# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import abc
from oslo_config import cfg
import six
CONF = cfg.CONF
@six.add_metaclass(abc.ABCMeta)
class Target(object):
"""Target object for block storage devices.
Base class for target object, where target
is data transport mechanism (target) specific calls.
This includes things like create targets, attach, detach
etc.
Base class here does nothing more than set an executor and db as
well as force implementation of required methods.
"""
def __init__(self, *args, **kwargs):
self.db = kwargs.get('db')
self.configuration = kwargs.get('configuration')
self._root_helper = kwargs.get('root_helper',
'sudo cinder-rootwrap %s' %
CONF.rootwrap_config)
@abc.abstractmethod
def ensure_export(self, context, volume, volume_path):
"""Synchronously recreates an export for a volume."""
pass
@abc.abstractmethod
def create_export(self, context, volume, volume_path):
"""Exports a Target/Volume.
Can optionally return a Dict of changes to
the volume object to be persisted.
"""
pass
@abc.abstractmethod
def remove_export(self, context, volume):
"""Removes an export for a Target/Volume."""
pass
@abc.abstractmethod
def initialize_connection(self, volume, connector):
"""Allow connection to connector and return connection info."""
pass
@abc.abstractmethod
def terminate_connection(self, volume, connector, **kwargs):
"""Disallow connection from connector."""
pass