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# Copyright 2010 United States Government as represented by the

# Administrator of the National Aeronautics and Space Administration.

# All Rights Reserved.

#

# 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.

"""

Drivers for volumes.

"""

import time

from oslo.config import cfg

from cinder import exception

from cinder.image import image_utils

from cinder.openstack.common import excutils

from cinder.openstack.common import fileutils

from cinder.openstack.common import log as logging

from cinder.openstack.common import processutils

from cinder import utils

from cinder.volume import iscsi

from cinder.volume import rpcapi as volume_rpcapi

from cinder.volume import utils as volume_utils

LOG = logging.getLogger(__name__)

volume_opts = [

cfg.IntOpt('num_shell_tries',

default=3,

help='number of times to attempt to run flakey shell commands'),

cfg.IntOpt('reserved_percentage',

default=0,

help='The percentage of backend capacity is reserved'),

cfg.IntOpt('iscsi_num_targets',

default=100,

help='The maximum number of iscsi target ids per host'),

cfg.StrOpt('iscsi_target_prefix',

default='iqn.2010-10.org.openstack:',

help='prefix for iscsi volumes'),

cfg.StrOpt('iscsi_ip_address',

default='$my_ip',

help='The IP address that the iSCSI daemon is listening on'),

cfg.IntOpt('iscsi_port',

default=3260,

help='The port that the iSCSI daemon is listening on'),

cfg.IntOpt('num_volume_device_scan_tries',

deprecated_name='num_iscsi_scan_tries',

default=3,

help='The maximum number of times to rescan targets'

' to find volume'),

cfg.StrOpt('volume_backend_name',

default=None,

help='The backend name for a given driver implementation'),

cfg.BoolOpt('use_multipath_for_image_xfer',

default=False,

help='Do we attach/detach volumes in cinder using multipath '

'for volume to image and image to volume transfers?'),

cfg.StrOpt('volume_clear',

default='zero',

help='Method used to wipe old voumes (valid options are: '

'none, zero, shred)'),

cfg.IntOpt('volume_clear_size',

default=0,

help='Size in MiB to wipe at start of old volumes. 0 => all'),

cfg.StrOpt('volume_clear_ionice',

default=None,

help='The flag to pass to ionice to alter the i/o priority '

'of the process used to zero a volume after deletion, '

'for example "-c3" for idle only priority.'),

cfg.StrOpt('iscsi_helper',

default='tgtadm',

help='iscsi target user-land tool to use'),

cfg.StrOpt('volumes_dir',

default='$state_path/volumes',

help='Volume configuration file storage '

'directory'),

cfg.StrOpt('iet_conf',

default='/etc/iet/ietd.conf',

help='IET configuration file'),

cfg.StrOpt('lio_initiator_iqns',

default='',

help=('Comma-separated list of initiator IQNs '

'allowed to connect to the '

'iSCSI target. (From Nova compute nodes.)')),

cfg.StrOpt('iscsi_iotype',

default='fileio',

help=('Sets the behavior of the iSCSI target '

'to either perform blockio or fileio '

'optionally, auto can be set and Cinder '

'will autodetect type of backing device')),

cfg.StrOpt('volume_dd_blocksize',

default='1M',

help='The default block size used when copying/clearing '

'volumes'),

]

# for backward compatibility

iser_opts = [

cfg.IntOpt('num_iser_scan_tries',

default=3,

help='The maximum number of times to rescan iSER target'

'to find volume'),

cfg.IntOpt('iser_num_targets',

default=100,

help='The maximum number of iser target ids per host'),

cfg.StrOpt('iser_target_prefix',

default='iqn.2010-10.org.iser.openstack:',

help='prefix for iser volumes'),

cfg.StrOpt('iser_ip_address',

default='$my_ip',

help='The IP address that the iSER daemon is listening on'),

cfg.IntOpt('iser_port',

default=3260,

help='The port that the iSER daemon is listening on'),

cfg.StrOpt('iser_helper',

default='tgtadm',

help='iser target user-land tool to use'),

]

CONF = cfg.CONF

CONF.register_opts(volume_opts)

CONF.register_opts(iser_opts)

**** CubicPower OpenStack Study ****

class VolumeDriver(object):

"""Executes commands relating to Volumes."""

VERSION = "N/A"

**** CubicPower OpenStack Study ****

    def __init__(self, execute=utils.execute, *args, **kwargs):

        # NOTE(vish): db is set by Manager

        self.db = kwargs.get('db')

        self.host = kwargs.get('host')

        self.configuration = kwargs.get('configuration', None)

        if self.configuration:

            self.configuration.append_config_values(volume_opts)

        self.set_execute(execute)

        self._stats = {}

        # set True by manager after successful check_for_setup

        self._initialized = False

**** CubicPower OpenStack Study ****

    def set_execute(self, execute):

        self._execute = execute

**** CubicPower OpenStack Study ****

    def set_initialized(self):

        self._initialized = True

    @property

**** CubicPower OpenStack Study ****

    def initialized(self):

        return self._initialized

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    def get_version(self):

        """Get the current version of this driver."""

        return self.VERSION

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    def _is_non_recoverable(self, err, non_recoverable_list):

        for item in non_recoverable_list:

            if item in err:

                return True

        return False

**** CubicPower OpenStack Study ****

    def _try_execute(self, *command, **kwargs):

        # NOTE(vish): Volume commands can partially fail due to timing, but

        #             running them a second time on failure will usually

        #             recover nicely.

        non_recoverable = kwargs.pop('no_retry_list', [])

        tries = 0

        while True:

            try:

                self._execute(*command, **kwargs)

                return True

            except processutils.ProcessExecutionError as ex:

                tries = tries + 1

                if tries >= self.configuration.num_shell_tries or\

                        self._is_non_recoverable(ex.stderr, non_recoverable):

                    raise

                LOG.exception(_("Recovering from a failed execute.  "

                                "Try number %s"), tries)

                time.sleep(tries ** 2)

**** CubicPower OpenStack Study ****

    def check_for_setup_error(self):

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def create_volume(self, volume):

        """Creates a volume. Can optionally return a Dictionary of

        changes to the volume object to be persisted.

        """

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def create_volume_from_snapshot(self, volume, snapshot):

        """Creates a volume from a snapshot."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def create_cloned_volume(self, volume, src_vref):

        """Creates a clone of the specified volume."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def delete_volume(self, volume):

        """Deletes a volume."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def create_snapshot(self, snapshot):

        """Creates a snapshot."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def delete_snapshot(self, snapshot):

        """Deletes a snapshot."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def local_path(self, volume):

        raise NotImplementedError()

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    def ensure_export(self, context, volume):

        """Synchronously recreates an export for a volume."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def create_export(self, context, volume):

        """Exports the volume. Can optionally return a Dictionary of changes

        to the volume object to be persisted.

        """

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def remove_export(self, context, volume):

        """Removes an export for a volume."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def initialize_connection(self, volume, connector):

        """Allow connection to connector and return connection info."""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def terminate_connection(self, volume, connector, **kwargs):

        """Disallow connection from connector"""

        raise NotImplementedError()

**** CubicPower OpenStack Study ****

    def attach_volume(self, context, volume, instance_uuid, host_name,

                      mountpoint):

        """Callback for volume attached to instance or host."""

        pass

**** CubicPower OpenStack Study ****

    def detach_volume(self, context, volume):

        """Callback for volume detached."""

        pass

**** CubicPower OpenStack Study ****

    def get_volume_stats(self, refresh=False):

        """Return the current state of the volume service. If 'refresh' is

           True, run the update first.

        """

        return None

**** CubicPower OpenStack Study ****

    def do_setup(self, context):

        """Any initialization the volume driver does while starting."""

        pass

**** CubicPower OpenStack Study ****

    def validate_connector(self, connector):

        """Fail if connector doesn't contain all the data needed by driver."""

        pass

**** CubicPower OpenStack Study ****

    def copy_volume_data(self, context, src_vol, dest_vol, remote=None):

        """Copy data from src_vol to dest_vol."""

        LOG.debug(_('copy_data_between_volumes %(src)s -> %(dest)s.')

                  % {'src': src_vol['name'], 'dest': dest_vol['name']})

        properties = utils.brick_get_connector_properties()

        dest_remote = True if remote in ['dest', 'both'] else False

        dest_orig_status = dest_vol['status']

        try:

            dest_attach_info = self._attach_volume(context,

                                                   dest_vol,

                                                   properties,

                                                   remote=dest_remote)

        except Exception:

            with excutils.save_and_reraise_exception():

                msg = _("Failed to attach volume %(vol)s")

                LOG.error(msg % {'vol': dest_vol['id']})

                self.db.volume_update(context, dest_vol['id'],

                                      {'status': dest_orig_status})

        src_remote = True if remote in ['src', 'both'] else False

        src_orig_status = src_vol['status']

        try:

            src_attach_info = self._attach_volume(context,

                                                  src_vol,

                                                  properties,

                                                  remote=src_remote)

        except Exception:

            with excutils.save_and_reraise_exception():

                msg = _("Failed to attach volume %(vol)s")

                LOG.error(msg % {'vol': src_vol['id']})

                self.db.volume_update(context, src_vol['id'],

                                      {'status': src_orig_status})

                self._detach_volume(context, dest_attach_info, dest_vol,

                                    properties, force=True, remote=dest_remote)

        try:

            size_in_mb = int(src_vol['size']) * 1024    # vol size is in GB

            volume_utils.copy_volume(

                src_attach_info['device']['path'],

                dest_attach_info['device']['path'],

                size_in_mb,

                self.configuration.volume_dd_blocksize)

            copy_error = False

        except Exception:

            with excutils.save_and_reraise_exception():

                msg = _("Failed to copy volume %(src)s to %(dest)d")

                LOG.error(msg % {'src': src_vol['id'], 'dest': dest_vol['id']})

                copy_error = True

        finally:

            self._detach_volume(context, dest_attach_info, dest_vol,

                                properties, force=copy_error,

                                remote=dest_remote)

            self._detach_volume(context, src_attach_info, src_vol,

                                properties, force=copy_error,

                                remote=src_remote)

**** CubicPower OpenStack Study ****

    def copy_image_to_volume(self, context, volume, image_service, image_id):

        """Fetch the image from image_service and write it to the volume."""

        LOG.debug(_('copy_image_to_volume %s.') % volume['name'])

        properties = utils.brick_get_connector_properties()

        attach_info = self._attach_volume(context, volume, properties)

        try:

            image_utils.fetch_to_raw(context,

                                     image_service,

                                     image_id,

                                     attach_info['device']['path'],

                                     self.configuration.volume_dd_blocksize,

                                     size=volume['size'])

        finally:

            self._detach_volume(context, attach_info, volume, properties)

**** CubicPower OpenStack Study ****

    def copy_volume_to_image(self, context, volume, image_service, image_meta):

        """Copy the volume to the specified image."""

        LOG.debug(_('copy_volume_to_image %s.') % volume['name'])

        properties = utils.brick_get_connector_properties()

        attach_info = self._attach_volume(context, volume, properties)

        try:

            image_utils.upload_volume(context,

                                      image_service,

                                      image_meta,

                                      attach_info['device']['path'])

        finally:

            self._detach_volume(context, attach_info, volume, properties)

**** CubicPower OpenStack Study ****

    def _attach_volume(self, context, volume, properties, remote=False):

        """Attach the volume."""

        if remote:

            # Call remote manager's initialize_connection which includes

            # driver's create_export and initialize_connection

            rpcapi = volume_rpcapi.VolumeAPI()

            conn = rpcapi.initialize_connection(context, volume, properties)

        else:

            # Call local driver's create_export and initialize_connection.

            # NOTE(avishay) This is copied from the manager's code - need to

            # clean this up in the future.

            model_update = None

            try:

                LOG.debug(_("Volume %s: creating export"), volume['id'])

                model_update = self.create_export(context, volume)

                if model_update:

                    volume = self.db.volume_update(context, volume['id'],

                                                   model_update)

            except exception.CinderException as ex:

                if model_update:

                    LOG.exception(_("Failed updating model of volume "

                                    "%(volume_id)s with driver provided model "

                                    "%(model)s") %

                                  {'volume_id': volume['id'],

                                   'model': model_update})

                    raise exception.ExportFailure(reason=ex)

            try:

                conn = self.initialize_connection(volume, properties)

            except Exception as err:

                try:

                    err_msg = (_('Unable to fetch connection information from '

                                 'backend: %(err)s') % {'err': err})

                    LOG.error(err_msg)

                    LOG.debug("Cleaning up failed connect initialization.")

                    self.remove_export(context, volume)

                except Exception as ex:

                    ex_msg = (_('Error encountered during cleanup '

                                'of a failed attach: %(ex)s') % {'ex': ex})

                    LOG.error(err_msg)

                    raise exception.VolumeBackendAPIException(data=ex_msg)

                raise exception.VolumeBackendAPIException(data=err_msg)

        # Use Brick's code to do attach/detach

        use_multipath = self.configuration.use_multipath_for_image_xfer

        device_scan_attempts = self.configuration.num_volume_device_scan_tries

        protocol = conn['driver_volume_type']

        connector = utils.brick_get_connector(protocol,

                                              use_multipath=use_multipath,

                                              device_scan_attempts=

                                              device_scan_attempts,

                                              conn=conn)

        device = connector.connect_volume(conn['data'])

        host_device = device['path']

        if not connector.check_valid_device(host_device):

            raise exception.DeviceUnavailable(path=host_device,

                                              reason=(_("Unable to access "

                                                        "the backend storage "

                                                        "via the path "

                                                        "%(path)s.") %

                                                      {'path': host_device}))

        return {'conn': conn, 'device': device, 'connector': connector}

**** CubicPower OpenStack Study ****

    def _detach_volume(self, context, attach_info, volume, properties,

                       force=False, remote=False):

        """Disconnect the volume from the host."""

        # Use Brick's code to do attach/detach

        connector = attach_info['connector']

        connector.disconnect_volume(attach_info['conn']['data'],

                                    attach_info['device'])

        if remote:

            # Call remote manager's terminate_connection which includes

            # driver's terminate_connection and remove export

            rpcapi = volume_rpcapi.VolumeAPI()

            rpcapi.terminate_connection(context, volume, properties,

                                        force=force)

        else:

            # Call local driver's terminate_connection and remove export.

            # NOTE(avishay) This is copied from the manager's code - need to

            # clean this up in the future.

            try:

                self.terminate_connection(volume, properties, force=force)

            except Exception as err:

                err_msg = (_('Unable to terminate volume connection: %(err)s')

                           % {'err': err})

                LOG.error(err_msg)

                raise exception.VolumeBackendAPIException(data=err_msg)

            try:

                LOG.debug(_("volume %s: removing export"), volume['id'])

                self.remove_export(context, volume)

            except Exception as ex:

                LOG.exception(_("Error detaching volume %(volume)s, "

                                "due to remove export failure."),

                              {"volume": volume['id']})

                raise exception.RemoveExportException(volume=volume['id'],

                                                      reason=ex)

**** CubicPower OpenStack Study ****

    def clone_image(self, volume, image_location, image_id, image_meta):

        """Create a volume efficiently from an existing image.

        image_location is a string whose format depends on the

        image service backend in use. The driver should use it

        to determine whether cloning is possible.

        image_id is a string which represents id of the image.

        It can be used by the driver to introspect internal

        stores or registry to do an efficient image clone.

        image_meta is a dictionary that includes 'disk_format' (e.g.

        raw, qcow2) and other image attributes that allow drivers to

        decide whether they can clone the image without first requiring

        conversion.

        Returns a dict of volume properties eg. provider_location,

        boolean indicating whether cloning occurred

        """

        return None, False

**** CubicPower OpenStack Study ****

    def backup_volume(self, context, backup, backup_service):

        """Create a new backup from an existing volume."""

        volume = self.db.volume_get(context, backup['volume_id'])

        LOG.debug(_('Creating a new backup for volume %s.') %

                  volume['name'])

        properties = utils.brick_get_connector_properties()

        attach_info = self._attach_volume(context, volume, properties)

        try:

            volume_path = attach_info['device']['path']

            with utils.temporary_chown(volume_path):

                with fileutils.file_open(volume_path) as volume_file:

                    backup_service.backup(backup, volume_file)

        finally:

            self._detach_volume(context, attach_info, volume, properties)

**** CubicPower OpenStack Study ****

    def restore_backup(self, context, backup, volume, backup_service):

        """Restore an existing backup to a new or existing volume."""

        LOG.debug(_('Restoring backup %(backup)s to '

                    'volume %(volume)s.') %

                  {'backup': backup['id'],

                   'volume': volume['name']})

        properties = utils.brick_get_connector_properties()

        attach_info = self._attach_volume(context, volume, properties)

        try:

            volume_path = attach_info['device']['path']

            with utils.temporary_chown(volume_path):

                with fileutils.file_open(volume_path, 'wb') as volume_file:

                    backup_service.restore(backup, volume['id'], volume_file)

        finally:

            self._detach_volume(context, attach_info, volume, properties)

**** CubicPower OpenStack Study ****

    def clear_download(self, context, volume):

        """Clean up after an interrupted image copy."""

        pass

**** CubicPower OpenStack Study ****

    def extend_volume(self, volume, new_size):

        msg = _("Extend volume not implemented")

        raise NotImplementedError(msg)

**** CubicPower OpenStack Study ****

    def migrate_volume(self, context, volume, host):

        """Migrate the volume to the specified host.

        Returns a boolean indicating whether the migration occurred, as well as

        model_update.

        :param ctxt: Context

        :param volume: A dictionary describing the volume to migrate

        :param host: A dictionary describing the host to migrate to, where

                     host['host'] is its name, and host['capabilities'] is a

                     dictionary of its reported capabilities.

        """

        return (False, None)

**** CubicPower OpenStack Study ****

    def retype(self, context, volume, new_type, diff, host):

        """Convert the volume to be of the new type.

        Returns a boolean indicating whether the retype occurred.

        :param ctxt: Context

        :param volume: A dictionary describing the volume to migrate

        :param new_type: A dictionary describing the volume type to convert to

        :param diff: A dictionary with the difference between the two types

        :param host: A dictionary describing the host to migrate to, where

                     host['host'] is its name, and host['capabilities'] is a

                     dictionary of its reported capabilities.

        """

        return False

**** CubicPower OpenStack Study ****

    def accept_transfer(self, context, volume, new_user, new_project):

        """Accept the transfer of a volume for a new user/project."""

        pass

**** CubicPower OpenStack Study ****

    def manage_existing(self, volume, existing_ref):

        """Brings an existing backend storage object under Cinder management.

        existing_ref is passed straight through from the API request's

        manage_existing_ref value, and it is up to the driver how this should

        be interpreted.  It should be sufficient to identify a storage object

        that the driver should somehow associate with the newly-created cinder

        volume structure.

        There are two ways to do this:

        1. Rename the backend storage object so that it matches the,

           volume['name'] which is how drivers traditionally map between a

           cinder volume and the associated backend storage object.

        2. Place some metadata on the volume, or somewhere in the backend, that

           allows other driver requests (e.g. delete, clone, attach, detach...)

           to locate the backend storage object when required.

        If the existing_ref doesn't make sense, or doesn't refer to an existing

        backend storage object, raise a ManageExistingInvalidReference

        exception.

        The volume may have a volume_type, and the driver can inspect that and

        compare against the properties of the referenced backend storage

        object.  If they are incompatible, raise a

        ManageExistingVolumeTypeMismatch, specifying a reason for the failure.

        """

        msg = _("Manage existing volume not implemented.")

        raise NotImplementedError(msg)

**** CubicPower OpenStack Study ****

    def manage_existing_get_size(self, volume, existing_ref):

        """Return size of volume to be managed by manage_existing.

        When calculating the size, round up to the next GB.

        """

        msg = _("Manage existing volume not implemented.")

        raise NotImplementedError(msg)

**** CubicPower OpenStack Study ****

    def unmanage(self, volume):

        """Removes the specified volume from Cinder management.

        Does not delete the underlying backend storage object.

        For most drivers, this will not need to do anything.  However, some

        drivers might use this call as an opportunity to clean up any

        Cinder-specific configuration that they have associated with the

        backend storage object.

        """

        pass

**** CubicPower OpenStack Study ****

class ISCSIDriver(VolumeDriver):

"""Executes commands relating to ISCSI volumes.

We make use of model provider properties as follows:

``provider_location``

if present, contains the iSCSI target information in the same

format as an ietadm discovery

i.e. ':, '

``provider_auth``

if present, contains a space-separated triple:

' '.

`CHAP` is the only auth_method in use at the moment.

"""

**** CubicPower OpenStack Study ****

    def __init__(self, *args, **kwargs):

        super(ISCSIDriver, self).__init__(*args, **kwargs)

**** CubicPower OpenStack Study ****

    def _do_iscsi_discovery(self, volume):

        #TODO(justinsb): Deprecate discovery and use stored info

        #NOTE(justinsb): Discovery won't work with CHAP-secured targets (?)

        LOG.warn(_("ISCSI provider_location not stored, using discovery"))

        volume_name = volume['name']

        try:

            # NOTE(griff) We're doing the split straight away which should be

            # safe since using '@' in hostname is considered invalid

            (out, _err) = self._execute('iscsiadm', '-m', 'discovery',

                                        '-t', 'sendtargets', '-p',

                                        volume['host'].split('@')[0],

                                        run_as_root=True)

        except processutils.ProcessExecutionError as ex:

            LOG.error(_("ISCSI discovery attempt failed for:%s") %

                      volume['host'].split('@')[0])

            LOG.debug(_("Error from iscsiadm -m discovery: %s") % ex.stderr)

            return None

        for target in out.splitlines():

            if (self.configuration.iscsi_ip_address in target

                    and volume_name in target):

                return target

        return None

**** CubicPower OpenStack Study ****

    def _get_iscsi_properties(self, volume):

        """Gets iscsi configuration

        We ideally get saved information in the volume entity, but fall back

        to discovery if need be. Discovery may be completely removed in future

        The properties are:

        :target_discovered:    boolean indicating whether discovery was used

        :target_iqn:    the IQN of the iSCSI target

        :target_portal:    the portal of the iSCSI target

        :target_lun:    the lun of the iSCSI target

        :volume_id:    the id of the volume (currently used by xen)

        :auth_method:, :auth_username:, :auth_password:

            the authentication details. Right now, either auth_method is not

            present meaning no authentication, or auth_method == `CHAP`

            meaning use CHAP with the specified credentials.

        :access_mode:    the volume access mode allow client used

                         ('rw' or 'ro' currently supported)

        """

        properties = {}

        location = volume['provider_location']

        if location:

            # provider_location is the same format as iSCSI discovery output

            properties['target_discovered'] = False

        else:

            location = self._do_iscsi_discovery(volume)

            if not location:

                msg = (_("Could not find iSCSI export for volume %s") %

                        (volume['name']))

                raise exception.InvalidVolume(reason=msg)

            LOG.debug(_("ISCSI Discovery: Found %s") % (location))

            properties['target_discovered'] = True

        results = location.split(" ")

        properties['target_portal'] = results[0].split(",")[0]

        properties['target_iqn'] = results[1]

        try:

            properties['target_lun'] = int(results[2])

        except (IndexError, ValueError):

            if (self.configuration.volume_driver in

                    ['cinder.volume.drivers.lvm.LVMISCSIDriver',

                     'cinder.volume.drivers.lvm.ThinLVMVolumeDriver'] and

                    self.configuration.iscsi_helper == 'tgtadm'):

                properties['target_lun'] = 1

            else:

                properties['target_lun'] = 0

        properties['volume_id'] = volume['id']

        auth = volume['provider_auth']

        if auth:

            (auth_method, auth_username, auth_secret) = auth.split()

            properties['auth_method'] = auth_method

            properties['auth_username'] = auth_username

            properties['auth_password'] = auth_secret

        geometry = volume.get('provider_geometry', None)

        if geometry:

            (physical_block_size, logical_block_size) = geometry.split()

            properties['physical_block_size'] = physical_block_size

            properties['logical_block_size'] = logical_block_size

        encryption_key_id = volume.get('encryption_key_id', None)

        properties['encrypted'] = encryption_key_id is not None

        return properties

**** CubicPower OpenStack Study ****

    def _run_iscsiadm(self, iscsi_properties, iscsi_command, **kwargs):

        check_exit_code = kwargs.pop('check_exit_code', 0)

        (out, err) = self._execute('iscsiadm', '-m', 'node', '-T',

                                   iscsi_properties['target_iqn'],

                                   '-p', iscsi_properties['target_portal'],

                                   *iscsi_command, run_as_root=True,

                                   check_exit_code=check_exit_code)

        LOG.debug("iscsiadm %s: stdout=%s stderr=%s" %

                  (iscsi_command, out, err))

        return (out, err)

**** CubicPower OpenStack Study ****

    def _run_iscsiadm_bare(self, iscsi_command, **kwargs):

        check_exit_code = kwargs.pop('check_exit_code', 0)

        (out, err) = self._execute('iscsiadm',

                                   *iscsi_command,

                                   run_as_root=True,

                                   check_exit_code=check_exit_code)

        LOG.debug("iscsiadm %s: stdout=%s stderr=%s" %

                  (iscsi_command, out, err))

        return (out, err)

**** CubicPower OpenStack Study ****

    def _iscsiadm_update(self, iscsi_properties, property_key, property_value,

                         **kwargs):

        iscsi_command = ('--op', 'update', '-n', property_key,

                         '-v', property_value)

        return self._run_iscsiadm(iscsi_properties, iscsi_command, **kwargs)

**** CubicPower OpenStack Study ****

    def initialize_connection(self, volume, connector):

        """Initializes the connection and returns connection info.

        The iscsi driver returns a driver_volume_type of 'iscsi'.

        The format of the driver data is defined in _get_iscsi_properties.

        Example return value::

            {

                'driver_volume_type': 'iscsi'

                'data': {

                    'target_discovered': True,

                    'target_iqn': 'iqn.2010-10.org.openstack:volume-00000001',

                    'target_portal': '127.0.0.0.1:3260',

                    'volume_id': 1,

                    'access_mode': 'rw'

                }

            }

        """

        if CONF.iscsi_helper == 'lioadm':

            self.target_helper.initialize_connection(volume, connector)

        iscsi_properties = self._get_iscsi_properties(volume)

        return {

            'driver_volume_type': 'iscsi',

            'data': iscsi_properties

        }

**** CubicPower OpenStack Study ****

    def validate_connector(self, connector):

        # iSCSI drivers require the initiator information

        if 'initiator' not in connector:

            err_msg = (_('The volume driver requires the iSCSI initiator '

                         'name in the connector.'))

            LOG.error(err_msg)

            raise exception.VolumeBackendAPIException(data=err_msg)

**** CubicPower OpenStack Study ****

    def terminate_connection(self, volume, connector, **kwargs):

        pass

**** CubicPower OpenStack Study ****

    def get_volume_stats(self, refresh=False):

        """Get volume stats.

        If 'refresh' is True, run update the stats first.

        """

        if refresh:

            self._update_volume_stats()

        return self._stats

**** CubicPower OpenStack Study ****

    def _update_volume_stats(self):

        """Retrieve stats info from volume group."""

        LOG.debug(_("Updating volume stats"))

        data = {}

        backend_name = self.configuration.safe_get('volume_backend_name')

        data["volume_backend_name"] = backend_name or 'Generic_iSCSI'

        data["vendor_name"] = 'Open Source'

        data["driver_version"] = '1.0'

        data["storage_protocol"] = 'iSCSI'

        data['total_capacity_gb'] = 'infinite'

        data['free_capacity_gb'] = 'infinite'

        data['reserved_percentage'] = 100

        data['QoS_support'] = False

        self._stats = data

**** CubicPower OpenStack Study ****

    def get_target_helper(self, db):

        root_helper = utils.get_root_helper()

        if CONF.iscsi_helper == 'iseradm':

            return iscsi.ISERTgtAdm(root_helper, CONF.volumes_dir,

                                    CONF.iscsi_target_prefix, db=db)

        elif CONF.iscsi_helper == 'tgtadm':

            return iscsi.TgtAdm(root_helper,

                                CONF.volumes_dir,

                                CONF.iscsi_target_prefix,

                                db=db)

        elif CONF.iscsi_helper == 'fake':

            return iscsi.FakeIscsiHelper()

        elif CONF.iscsi_helper == 'lioadm':

            return iscsi.LioAdm(root_helper,

                                CONF.lio_initiator_iqns,

                                CONF.iscsi_target_prefix, db=db)

        else:

            return iscsi.IetAdm(root_helper, CONF.iet_conf, CONF.iscsi_iotype,

                                db=db)

**** CubicPower OpenStack Study ****

class FakeISCSIDriver(ISCSIDriver):

"""Logs calls instead of executing."""

**** CubicPower OpenStack Study ****

    def __init__(self, *args, **kwargs):

        super(FakeISCSIDriver, self).__init__(execute=self.fake_execute,

                                              *args, **kwargs)

**** CubicPower OpenStack Study ****

    def create_volume(self, volume):

        pass

**** CubicPower OpenStack Study ****

    def check_for_setup_error(self):

        """No setup necessary in fake mode."""

        pass

**** CubicPower OpenStack Study ****

    def initialize_connection(self, volume, connector):

        return {

            'driver_volume_type': 'iscsi',

            'data': {'access_mode': 'rw'}

        }

**** CubicPower OpenStack Study ****

    def terminate_connection(self, volume, connector, **kwargs):

        pass

    @staticmethod

**** CubicPower OpenStack Study ****

    def fake_execute(cmd, *_args, **_kwargs):

        """Execute that simply logs the command."""

        LOG.debug(_("FAKE ISCSI: %s"), cmd)

        return (None, None)

**** CubicPower OpenStack Study ****

class ISERDriver(ISCSIDriver):

"""Executes commands relating to ISER volumes.

We make use of model provider properties as follows:

``provider_location``

if present, contains the iSER target information in the same

format as an ietadm discovery

i.e. ':, '

``provider_auth``

if present, contains a space-separated triple:

' '.

`CHAP` is the only auth_method in use at the moment.

"""

**** CubicPower OpenStack Study ****

    def __init__(self, *args, **kwargs):

        super(ISERDriver, self).__init__(*args, **kwargs)

        # for backward compatibility

        self.configuration.num_iscsi_scan_tries = \

            self.configuration.num_iser_scan_tries

        self.configuration.iscsi_num_targets = \

            self.configuration.iser_num_targets

        self.configuration.iscsi_target_prefix = \

            self.configuration.iser_target_prefix

        self.configuration.iscsi_ip_address = \

            self.configuration.iser_ip_address

        self.configuration.iser_port = self.configuration.iser_port

**** CubicPower OpenStack Study ****

    def initialize_connection(self, volume, connector):

        """Initializes the connection and returns connection info.

        The iser driver returns a driver_volume_type of 'iser'.

        The format of the driver data is defined in _get_iser_properties.

        Example return value::

            {

                'driver_volume_type': 'iser'

                'data': {

                    'target_discovered': True,

                    'target_iqn':

                    'iqn.2010-10.org.iser.openstack:volume-00000001',

                    'target_portal': '127.0.0.0.1:3260',

                    'volume_id': 1,

                }

            }

        """

        iser_properties = self._get_iscsi_properties(volume)

        return {

            'driver_volume_type': 'iser',

            'data': iser_properties

        }

**** CubicPower OpenStack Study ****

    def _update_volume_stats(self):

        """Retrieve stats info from volume group."""

        LOG.debug(_("Updating volume stats"))

        data = {}

        backend_name = self.configuration.safe_get('volume_backend_name')

        data["volume_backend_name"] = backend_name or 'Generic_iSER'

        data["vendor_name"] = 'Open Source'

        data["driver_version"] = '1.0'

        data["storage_protocol"] = 'iSER'

        data['total_capacity_gb'] = 'infinite'

        data['free_capacity_gb'] = 'infinite'

        data['reserved_percentage'] = 100

        data['QoS_support'] = False

        self._stats = data

**** CubicPower OpenStack Study ****

    def get_target_helper(self, db):

        root_helper = utils.get_root_helper()

        if CONF.iser_helper == 'fake':

            return iscsi.FakeIscsiHelper()

        else:

            return iscsi.ISERTgtAdm(root_helper,

                                    CONF.volumes_dir, db=db)

**** CubicPower OpenStack Study ****

class FakeISERDriver(FakeISCSIDriver):

"""Logs calls instead of executing."""

**** CubicPower OpenStack Study ****

    def __init__(self, *args, **kwargs):

        super(FakeISERDriver, self).__init__(execute=self.fake_execute,

                                             *args, **kwargs)

**** CubicPower OpenStack Study ****

    def initialize_connection(self, volume, connector):

        return {

            'driver_volume_type': 'iser',

            'data': {}

        }

    @staticmethod

**** CubicPower OpenStack Study ****

    def fake_execute(cmd, *_args, **_kwargs):

        """Execute that simply logs the command."""

        LOG.debug(_("FAKE ISER: %s"), cmd)

        return (None, None)

**** CubicPower OpenStack Study ****

class FibreChannelDriver(VolumeDriver):

"""Executes commands relating to Fibre Channel volumes."""

**** CubicPower OpenStack Study ****

    def __init__(self, *args, **kwargs):

        super(FibreChannelDriver, self).__init__(*args, **kwargs)

**** CubicPower OpenStack Study ****

    def initialize_connection(self, volume, connector):

        """Initializes the connection and returns connection info.

        The  driver returns a driver_volume_type of 'fibre_channel'.

        The target_wwn can be a single entry or a list of wwns that

        correspond to the list of remote wwn(s) that will export the volume.

        Example return values:

            {

                'driver_volume_type': 'fibre_channel'

                'data': {

                    'target_discovered': True,

                    'target_lun': 1,

                    'target_wwn': '1234567890123',

                    'access_mode': 'rw'

                }

            }

            or

             {

                'driver_volume_type': 'fibre_channel'

                'data': {

                    'target_discovered': True,

                    'target_lun': 1,

                    'target_wwn': ['1234567890123', '0987654321321'],

                    'access_mode': 'rw'

                }

            }

        """

        msg = _("Driver must implement initialize_connection")

        raise NotImplementedError(msg)