cinder/cinder/volume/drivers/vzstorage.py
Jay S. Bryant cf01d7eaf3 Mark Virtuozzo Driver Unsupported
The Virtuozzo driver CI has not reported success in months
and the maintainers have not responded to any of the notes that
have been sent out.

As a result, we need to mark the drivers unsupported
for the T release.

Change-Id: Ic9c239baff19ec9cfbc1a114cdd9a899a34bedd6
2019-09-06 09:13:08 -05:00

744 lines
29 KiB
Python

# Copyright (c) 2015 Parallels IP Holdings GmbH
# 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.
import collections
import errno
import json
import os
import re
from os_brick.remotefs import remotefs
from oslo_concurrency import processutils as putils
from oslo_config import cfg
from oslo_log import log as logging
from oslo_utils import imageutils
from oslo_utils import units
from cinder import exception
from cinder.i18n import _
from cinder.image import image_utils
from cinder import interface
from cinder import utils
from cinder.volume import configuration
from cinder.volume.drivers import remotefs as remotefs_drv
LOG = logging.getLogger(__name__)
vzstorage_opts = [
cfg.StrOpt('vzstorage_shares_config',
default='/etc/cinder/vzstorage_shares',
help='File with the list of available vzstorage shares.'),
cfg.BoolOpt('vzstorage_sparsed_volumes',
default=True,
help=('Create volumes as sparsed files which take no space '
'rather than regular files when using raw format, '
'in which case volume creation takes lot of time.')),
cfg.FloatOpt('vzstorage_used_ratio',
default=0.95,
help=('Percent of ACTUAL usage of the underlying volume '
'before no new volumes can be allocated to the volume '
'destination.')),
cfg.StrOpt('vzstorage_mount_point_base',
default='$state_path/mnt',
help=('Base dir containing mount points for '
'vzstorage shares.')),
cfg.ListOpt('vzstorage_mount_options',
help=('Mount options passed to the vzstorage client. '
'See section of the pstorage-mount man page '
'for details.')),
cfg.StrOpt('vzstorage_default_volume_format',
default='raw',
help=('Default format that will be used when creating volumes '
'if no volume format is specified.')),
]
CONF = cfg.CONF
CONF.register_opts(vzstorage_opts, group=configuration.SHARED_CONF_GROUP)
PLOOP_BASE_DELTA_NAME = 'root.hds'
DISK_FORMAT_RAW = 'raw'
DISK_FORMAT_QCOW2 = 'qcow2'
DISK_FORMAT_PLOOP = 'ploop'
class VzStorageException(exception.RemoteFSException):
message = _("Unknown Virtuozzo Storage exception")
class VzStorageNoSharesMounted(exception.RemoteFSNoSharesMounted):
message = _("No mounted Virtuozzo Storage shares found")
class VzStorageNoSuitableShareFound(exception.RemoteFSNoSuitableShareFound):
message = _("There is no share which can host %(volume_size)sG")
class PloopDevice(object):
"""Setup a ploop device for ploop image
This class is for mounting ploop devices using with statement:
with PloopDevice('/vzt/private/my-ct/harddisk.hdd') as dev_path:
# do something
:param path: A path to ploop harddisk dir
:param snapshot_id: Snapshot id to mount
:param execute: execute helper
"""
def __init__(self, path, snapshot_id=None, read_only=True,
execute=putils.execute):
self.path = path
self.snapshot_id = snapshot_id
self.read_only = read_only
self.execute = execute
def __enter__(self):
self.dd_path = os.path.join(self.path, 'DiskDescriptor.xml')
cmd = ['ploop', 'mount', self.dd_path]
if self.snapshot_id:
cmd.append('-u')
cmd.append(self.snapshot_id)
if self.read_only:
cmd.append('-r')
out, err = self.execute(*cmd, run_as_root=True)
m = re.search(r'dev=(\S+)', out)
if not m:
raise Exception('Invalid output from ploop mount: %s' % out)
self.ploop_dev = m.group(1)
return self.ploop_dev
def _umount(self):
self.execute('ploop', 'umount', self.dd_path, run_as_root=True)
def __exit__(self, type, value, traceback):
self._umount()
@interface.volumedriver
class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
"""Cinder driver for Virtuozzo Storage.
Creates volumes as files on the mounted vzstorage cluster.
.. code-block:: none
Version history:
1.0 - Initial driver.
1.1 - Supports vz:volume_format in vendor properties.
"""
VERSION = '1.1'
CI_WIKI_NAME = "Virtuozzo_Storage_CI"
# TODO(jsbryant) Remove driver in the 'U' release if CI is not fixed.
SUPPORTED = False
SHARE_FORMAT_REGEX = r'(?:(\S+):\/)?([a-zA-Z0-9_-]+)(?::(\S+))?'
def __init__(self, execute=putils.execute, *args, **kwargs):
self.driver_volume_type = 'vzstorage'
self.driver_prefix = 'vzstorage'
self.volume_backend_name = 'Virtuozzo_Storage'
self._remotefsclient = None
super(VZStorageDriver, self).__init__(*args, **kwargs)
self.configuration.append_config_values(vzstorage_opts)
self._execute_as_root = False
root_helper = utils.get_root_helper()
# base bound to instance is used in RemoteFsConnector.
self.base = self.configuration.vzstorage_mount_point_base
opts = self.configuration.vzstorage_mount_options
self._remotefsclient = remotefs.VZStorageRemoteFSClient(
'vzstorage', root_helper, execute=execute,
vzstorage_mount_point_base=self.base,
vzstorage_mount_options=opts)
@staticmethod
def get_driver_options():
return vzstorage_opts
def _update_volume_stats(self):
super(VZStorageDriver, self)._update_volume_stats()
self._stats['vendor_name'] = 'Virtuozzo'
def _init_vendor_properties(self):
namespace = 'vz'
properties = {}
self._set_property(
properties,
"%s:volume_format" % namespace,
"Volume format",
_("Specifies volume format."),
"string",
enum=["qcow2", "ploop", "raw"],
default=self.configuration.vzstorage_default_volume_format)
return properties, namespace
def _qemu_img_info(self, path, volume_name):
qemu_img_cache = path + ".qemu_img_info"
is_cache_outdated = True
if os.path.isdir(path):
# Ploop disks stored along with metadata xml as directories
# qemu-img should explore base data file inside
path = os.path.join(path, PLOOP_BASE_DELTA_NAME)
if os.path.isfile(qemu_img_cache):
info_tm = os.stat(qemu_img_cache).st_mtime
snap_tm = os.stat(path).st_mtime
if info_tm >= snap_tm:
is_cache_outdated = False
if is_cache_outdated:
LOG.debug("Cached qemu-img info %s not present or outdated,"
" refresh", qemu_img_cache)
ret = super(VZStorageDriver, self)._qemu_img_info_base(
path, volume_name,
self.configuration.vzstorage_mount_point_base)
# We need only backing_file and file_format
d = {'file_format': ret.file_format,
'backing_file': ret.backing_file}
with open(qemu_img_cache, "w") as f:
json.dump(d, f)
else:
ret = imageutils.QemuImgInfo()
with open(qemu_img_cache, "r") as f:
cached_data = json.load(f)
ret.file_format = cached_data['file_format']
ret.backing_file = cached_data['backing_file']
return ret
@remotefs_drv.locked_volume_id_operation
def initialize_connection(self, volume, connector):
"""Allow connection to connector and return connection info.
:param volume: volume reference
:param connector: connector reference
"""
# Find active image
active_file = self.get_active_image_from_info(volume)
data = {'export': volume.provider_location,
'format': self.get_volume_format(volume),
'name': active_file,
}
return {
'driver_volume_type': self.driver_volume_type,
'data': data,
'mount_point_base': self._get_mount_point_base(),
}
def do_setup(self, context):
"""Any initialization the volume driver does while starting."""
super(VZStorageDriver, self).do_setup(context)
config = self.configuration.vzstorage_shares_config
if not os.path.exists(config):
msg = (_("VzStorage config file at %(config)s doesn't exist.") %
{'config': config})
LOG.error(msg)
raise VzStorageException(msg)
if not os.path.isabs(self.base):
msg = _("Invalid mount point base: %s.") % self.base
LOG.error(msg)
raise VzStorageException(msg)
used_ratio = self.configuration.vzstorage_used_ratio
if not ((used_ratio > 0) and (used_ratio <= 1)):
msg = _("VzStorage config 'vzstorage_used_ratio' invalid. "
"Must be > 0 and <= 1.0: %s.") % used_ratio
LOG.error(msg)
raise VzStorageException(msg)
self.shares = {}
# Check if mount.fuse.pstorage is installed on this system;
# note that we don't need to be root to see if the package
# is installed.
package = 'mount.fuse.pstorage'
try:
self._execute(package, check_exit_code=False,
run_as_root=False)
except OSError as exc:
if exc.errno == errno.ENOENT:
msg = _('%s is not installed.') % package
raise VzStorageException(msg)
else:
raise
self.configuration.nas_secure_file_operations = 'true'
self.configuration.nas_secure_file_permissions = 'true'
def _ensure_share_mounted(self, share):
m = re.search(self.SHARE_FORMAT_REGEX, share)
if not m:
msg = (_("Invalid Virtuozzo Storage share specification: %r. "
"Must be: [MDS1[,MDS2],...:/]<CLUSTER NAME>[:PASSWORD].")
% share)
raise VzStorageException(msg)
cluster_name = m.group(2)
if share in self.shares:
mnt_flags = json.loads(self.shares[share])
else:
mnt_flags = []
if '-l' not in mnt_flags:
# If logging path is not specified in shares config
# set up logging to non-default path, so that it will
# be possible to mount the same cluster to another mount
# point by hand with default options.
mnt_flags.extend([
'-l', '/var/log/vstorage/%s/cinder.log.gz' % cluster_name])
self._remotefsclient.mount(share, mnt_flags)
def _find_share(self, volume):
"""Choose VzStorage share among available ones for given volume size.
For instances with more than one share that meets the criteria, the
first suitable share will be selected.
:param volume: the volume to be created.
"""
if not self._mounted_shares:
raise VzStorageNoSharesMounted()
for share in self._mounted_shares:
if self._is_share_eligible(share, volume.size):
break
else:
raise VzStorageNoSuitableShareFound(
volume_size=volume.size)
LOG.debug('Selected %s as target VzStorage share.', share)
return share
def _is_share_eligible(self, vz_share, volume_size_in_gib):
"""Verifies VzStorage share is eligible to host volume with given size.
:param vz_share: vzstorage share
:param volume_size_in_gib: int size in GB
"""
used_ratio = self.configuration.vzstorage_used_ratio
volume_size = volume_size_in_gib * units.Gi
total_size, available, allocated = self._get_capacity_info(vz_share)
if (allocated + volume_size) // total_size > used_ratio:
LOG.debug('_is_share_eligible: %s is above '
'vzstorage_used_ratio.', vz_share)
return False
return True
def choose_volume_format(self, volume):
volume_format = None
volume_type = volume.volume_type
# Retrieve volume format from volume metadata
if 'volume_format' in volume.metadata:
volume_format = volume.metadata['volume_format']
# If volume format wasn't found in metadata, use
# volume type extra specs
if not volume_format and volume_type:
extra_specs = volume_type.extra_specs or {}
if 'vz:volume_format' in extra_specs:
volume_format = extra_specs['vz:volume_format']
# If volume format is still undefined, return default
# volume format from backend configuration
return (volume_format or
self.configuration.vzstorage_default_volume_format)
def get_volume_format(self, volume):
active_file = self.get_active_image_from_info(volume)
active_file_path = os.path.join(self._local_volume_dir(volume),
active_file)
img_info = self._qemu_img_info(active_file_path, volume.name)
return image_utils.from_qemu_img_disk_format(img_info.file_format)
def _create_ploop(self, volume_path, volume_size):
os.mkdir(volume_path)
try:
self._execute('ploop', 'init', '-s', '%sG' % volume_size,
os.path.join(volume_path, PLOOP_BASE_DELTA_NAME),
run_as_root=True)
except putils.ProcessExecutionError:
os.rmdir(volume_path)
raise
def _do_create_volume(self, volume):
"""Create a volume on given vzstorage share.
:param volume: volume reference
"""
volume_format = self.choose_volume_format(volume)
volume_path = self.local_path(volume)
volume_size = volume.size
LOG.debug("Creating new volume at %s.", volume_path)
if os.path.exists(volume_path):
msg = _('File already exists at %s.') % volume_path
LOG.error(msg)
raise exception.InvalidVolume(reason=msg)
if volume_format == DISK_FORMAT_PLOOP:
self._create_ploop(volume_path, volume_size)
elif volume_format == DISK_FORMAT_QCOW2:
self._create_qcow2_file(volume_path, volume_size)
elif self.configuration.vzstorage_sparsed_volumes:
self._create_sparsed_file(volume_path, volume_size)
else:
self._create_regular_file(volume_path, volume_size)
info_path = self._local_path_volume_info(volume)
snap_info = {'active': os.path.basename(volume_path)}
self._write_info_file(info_path, snap_info)
# Query qemu-img info to cache the output
self._qemu_img_info(volume_path, volume.name)
def _delete(self, path):
self._execute('rm', '-rf', path, run_as_root=True)
@remotefs_drv.locked_volume_id_operation
def extend_volume(self, volume, size_gb):
LOG.info('Extending volume %s.', volume.id)
volume_format = self.get_volume_format(volume)
self._extend_volume(volume, size_gb, volume_format)
def _extend_volume(self, volume, size_gb, volume_format):
self._check_extend_volume_support(volume, size_gb)
LOG.info('Resizing file to %sG...', size_gb)
active_path = os.path.join(
self._get_mount_point_for_share(volume.provider_location),
self.get_active_image_from_info(volume))
self._do_extend_volume(active_path, size_gb, volume_format)
def _do_extend_volume(self, volume_path, size_gb, volume_format):
if volume_format == DISK_FORMAT_PLOOP:
self._execute('ploop', 'resize', '-s',
'%dG' % size_gb,
os.path.join(volume_path, 'DiskDescriptor.xml'),
run_as_root=True)
else:
image_utils.resize_image(volume_path, size_gb)
if not self._is_file_size_equal(volume_path, size_gb):
raise exception.ExtendVolumeError(
reason='Resizing image file failed.')
def _check_extend_volume_support(self, volume, size_gb):
extend_by = int(size_gb) - volume.size
if not self._is_share_eligible(volume.provider_location,
extend_by):
raise exception.ExtendVolumeError(reason='Insufficient space to '
'extend volume %s to %sG.'
% (volume.id, size_gb))
def _is_file_size_equal(self, path, size):
"""Checks if file size at path is equal to size."""
data = image_utils.qemu_img_info(path)
virt_size = data.virtual_size / units.Gi
return virt_size == size
def _recreate_ploop_desc(self, image_dir, image_file):
self._delete(os.path.join(image_dir, 'DiskDescriptor.xml'))
self._execute('ploop', 'restore-descriptor', image_dir, image_file)
def copy_image_to_volume(self, context, volume, image_service, image_id):
"""Fetch the image from image_service and write it to the volume."""
volume_format = self.get_volume_format(volume)
qemu_volume_format = image_utils.fixup_disk_format(volume_format)
image_path = self.local_path(volume)
if volume_format == DISK_FORMAT_PLOOP:
image_path = os.path.join(image_path, PLOOP_BASE_DELTA_NAME)
image_utils.fetch_to_volume_format(
context, image_service, image_id,
image_path, qemu_volume_format,
self.configuration.volume_dd_blocksize)
if volume_format == DISK_FORMAT_PLOOP:
self._recreate_ploop_desc(self.local_path(volume), image_path)
self._do_extend_volume(self.local_path(volume),
volume.size,
volume_format)
# Query qemu-img info to cache the output
self._qemu_img_info(self.local_path(volume), volume.name)
def _copy_volume_from_snapshot(self, snapshot, volume, volume_size):
"""Copy data from snapshot to destination volume.
This is done with a qemu-img convert to raw/qcow2 from the snapshot
qcow2.
"""
info_path = self._local_path_volume_info(snapshot.volume)
snap_info = self._read_info_file(info_path)
vol_dir = self._local_volume_dir(snapshot.volume)
out_format = self.choose_volume_format(volume)
qemu_out_format = image_utils.fixup_disk_format(out_format)
volume_format = self.get_volume_format(snapshot.volume)
volume_path = self.local_path(volume)
if volume_format in (DISK_FORMAT_QCOW2, DISK_FORMAT_RAW):
forward_file = snap_info[snapshot.id]
forward_path = os.path.join(vol_dir, forward_file)
# Find the file which backs this file, which represents the point
# when this snapshot was created.
img_info = self._qemu_img_info(forward_path,
snapshot.volume.name)
path_to_snap_img = os.path.join(vol_dir, img_info.backing_file)
LOG.debug("_copy_volume_from_snapshot: will copy "
"from snapshot at %s.", path_to_snap_img)
image_utils.convert_image(path_to_snap_img,
volume_path,
qemu_out_format)
elif volume_format == DISK_FORMAT_PLOOP:
with PloopDevice(self.local_path(snapshot.volume),
snapshot.id,
execute=self._execute) as dev:
base_file = os.path.join(volume_path, 'root.hds')
image_utils.convert_image(dev,
base_file,
qemu_out_format)
else:
msg = _("Unsupported volume format %s") % volume_format
raise exception.InvalidVolume(msg)
self._extend_volume(volume, volume_size, out_format)
# Query qemu-img info to cache the output
img_info = self._qemu_img_info(volume_path, volume.name)
@remotefs_drv.locked_volume_id_operation
def delete_volume(self, volume):
"""Deletes a logical volume."""
if not volume.provider_location:
msg = (_('Volume %s does not have provider_location '
'specified, skipping.') % volume.name)
LOG.error(msg)
return
self._ensure_share_mounted(volume.provider_location)
volume_dir = self._local_volume_dir(volume)
mounted_path = os.path.join(volume_dir,
self.get_active_image_from_info(volume))
if os.path.exists(mounted_path):
self._delete(mounted_path)
self._delete(mounted_path + ".qemu_img_info")
else:
LOG.info("Skipping deletion of volume %s "
"as it does not exist.", mounted_path)
info_path = self._local_path_volume_info(volume)
self._delete(info_path)
def _get_desc_path(self, volume):
return os.path.join(self.local_path(volume), 'DiskDescriptor.xml')
def _create_snapshot_ploop(self, snapshot):
status = snapshot.volume.status
if status != 'available':
msg = (_('Volume status must be available for '
'snapshot %(id)s. (is %(status)s)') %
{'id': snapshot.id, 'status': status})
raise exception.InvalidVolume(msg)
info_path = self._local_path_volume_info(snapshot.volume)
snap_info = self._read_info_file(info_path)
self._execute('ploop', 'snapshot', '-u', '{%s}' % snapshot.id,
self._get_desc_path(snapshot.volume),
run_as_root=True)
snap_file = os.path.join('volume-%s' % snapshot.volume.id, snapshot.id)
snap_info[snapshot.id] = snap_file
self._write_info_file(info_path, snap_info)
def _delete_snapshot_ploop(self, snapshot):
status = snapshot.volume.status
if status != 'available':
msg = (_('Volume status must be available for '
'snapshot %(id)s. (is %(status)s)') %
{'id': snapshot.id, 'status': status})
raise exception.InvalidVolume(msg)
info_path = self._local_path_volume_info(snapshot.volume)
snap_info = self._read_info_file(info_path)
self._execute('ploop', 'snapshot-delete', '-u', '{%s}' % snapshot.id,
self._get_desc_path(snapshot.volume),
run_as_root=True)
snap_info.pop(snapshot.id, None)
self._write_info_file(info_path, snap_info)
def _create_snapshot(self, snapshot):
volume_format = self.get_volume_format(snapshot.volume)
if volume_format == DISK_FORMAT_PLOOP:
self._create_snapshot_ploop(snapshot)
else:
super(VZStorageDriver, self)._create_snapshot(snapshot)
def _do_create_snapshot(self, snapshot, backing_filename,
new_snap_path):
super(VZStorageDriver, self)._do_create_snapshot(snapshot,
backing_filename,
new_snap_path)
# Cache qemu-img info for created snapshot
self._qemu_img_info(new_snap_path, snapshot.volume.name)
def _delete_snapshot_qcow2(self, snapshot):
info_path = self._local_path_volume_info(snapshot.volume)
snap_info = self._read_info_file(info_path, empty_if_missing=True)
if snapshot.id not in snap_info:
LOG.warning("Snapshot %s doesn't exist in snap_info",
snapshot.id)
return
snap_file = os.path.join(self._local_volume_dir(snapshot.volume),
snap_info[snapshot.id])
active_file = os.path.join(self._local_volume_dir(snapshot.volume),
snap_info['active'])
higher_file = self._get_higher_image_path(snapshot)
if higher_file:
higher_file = os.path.join(self._local_volume_dir(snapshot.volume),
higher_file)
elif active_file != snap_file:
msg = (_("Expected higher file exists for snapshot %s") %
snapshot.id)
raise VzStorageException(msg)
img_info = self._qemu_img_info(snap_file, snapshot.volume.name)
base_file = os.path.join(self._local_volume_dir(snapshot.volume),
img_info.backing_file)
super(VZStorageDriver, self)._delete_snapshot(snapshot)
def _qemu_info_cache(fn):
return fn + ".qemu_img_info"
def _update_backing_file(info_src, info_dst):
with open(info_src, 'r') as fs, open(info_dst, 'r') as fd:
src = json.load(fs)
dst = json.load(fd)
dst['backing_file'] = src['backing_file']
with open(info_dst, 'w') as fdw:
json.dump(dst, fdw)
if snap_file != active_file:
# mv snap_file.info higher_file.info
_update_backing_file(
_qemu_info_cache(snap_file),
_qemu_info_cache(higher_file))
self._delete(_qemu_info_cache(snap_file))
elif snapshot.volume.status == 'in-use':
# mv base_file.info snap_file.info
_update_backing_file(
_qemu_info_cache(base_file),
_qemu_info_cache(snap_file))
self._delete(_qemu_info_cache(base_file))
else:
# rm snap_file.info
self._delete(_qemu_info_cache(snap_file))
def _delete_snapshot(self, snapshot):
volume_format = self.get_volume_format(snapshot.volume)
if volume_format == DISK_FORMAT_PLOOP:
self._delete_snapshot_ploop(snapshot)
else:
self._delete_snapshot_qcow2(snapshot)
def _copy_volume_to_image(self, context, volume, image_service,
image_meta):
"""Copy the volume to the specified image."""
volume_format = self.get_volume_format(volume)
if volume_format == DISK_FORMAT_PLOOP:
with PloopDevice(self.local_path(volume),
execute=self._execute) as dev:
image_utils.upload_volume(context,
image_service,
image_meta,
dev,
volume_format='raw')
else:
super(VZStorageDriver, self)._copy_volume_to_image(context, volume,
image_service,
image_meta)
def _create_cloned_volume_ploop(self, volume, src_vref):
LOG.info('Cloning volume %(src)s to volume %(dst)s',
{'src': src_vref.id,
'dst': volume.id})
if src_vref.status != 'available':
msg = _("Volume status must be 'available'.")
raise exception.InvalidVolume(msg)
volume_name = CONF.volume_name_template % volume.id
# Create fake snapshot object
snap_attrs = ['volume_name', 'size', 'volume_size', 'name',
'volume_id', 'id', 'volume']
Snapshot = collections.namedtuple('Snapshot', snap_attrs)
temp_snapshot = Snapshot(id=src_vref.id,
volume_name=volume_name,
size=src_vref.size,
volume_size=src_vref.size,
name='clone-snap-%s' % src_vref.id,
volume_id=src_vref.id,
volume=src_vref)
self._create_snapshot_ploop(temp_snapshot)
try:
volume.provider_location = src_vref.provider_location
info_path = self._local_path_volume_info(volume)
snap_info = {'active': 'volume-%s' % volume.id}
self._write_info_file(info_path, snap_info)
self._copy_volume_from_snapshot(temp_snapshot,
volume,
volume.size)
finally:
self.delete_snapshot(temp_snapshot)
return {'provider_location': src_vref.provider_location}
def _create_cloned_volume(self, volume, src_vref, context):
"""Creates a clone of the specified volume."""
volume_format = self.get_volume_format(src_vref)
if volume_format == DISK_FORMAT_PLOOP:
return self._create_cloned_volume_ploop(volume, src_vref)
else:
return super(VZStorageDriver, self)._create_cloned_volume(volume,
src_vref)