¡@
OpenStack Study: imagebackend.py**** CubicPower OpenStack Study ****
# Copyright 2012 Grid Dynamics # 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 abc import contextlib import os import six from oslo.config import cfg from nova import exception from nova.openstack.common import excutils from nova.openstack.common import fileutils from nova.openstack.common.gettextutils import _ from nova.openstack.common import jsonutils from nova.openstack.common import log as logging from nova.openstack.common import units from nova import utils from nova.virt.disk import api as disk from nova.virt import images from nova.virt.libvirt import config as vconfig from nova.virt.libvirt import utils as libvirt_utils try: import rados import rbd except ImportError: rados = None rbd = None __imagebackend_opts = [ cfg.StrOpt('images_type', default='default', help='VM Images format. Acceptable values are: raw, qcow2, lvm,' ' rbd, default. If default is specified,' ' then use_cow_images flag is used instead of this one.', deprecated_group='DEFAULT', deprecated_name='libvirt_images_type'), cfg.StrOpt('images_volume_group', help='LVM Volume Group that is used for VM images, when you' ' specify images_type=lvm.', deprecated_group='DEFAULT', deprecated_name='libvirt_images_volume_group'), cfg.BoolOpt('sparse_logical_volumes', default=False, help='Create sparse logical volumes (with virtualsize)' ' if this flag is set to True.', deprecated_group='DEFAULT', deprecated_name='libvirt_sparse_logical_volumes'), cfg.StrOpt('volume_clear', default='zero', help='Method used to wipe old volumes (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('images_rbd_pool', default='rbd', help='The RADOS pool in which rbd volumes are stored', deprecated_group='DEFAULT', deprecated_name='libvirt_images_rbd_pool'), cfg.StrOpt('images_rbd_ceph_conf', default='', # default determined by librados help='Path to the ceph configuration file to use', deprecated_group='DEFAULT', deprecated_name='libvirt_images_rbd_ceph_conf'), ] CONF = cfg.CONF CONF.register_opts(__imagebackend_opts, 'libvirt') CONF.import_opt('image_cache_subdirectory_name', 'nova.virt.imagecache') CONF.import_opt('preallocate_images', 'nova.virt.driver') LOG = logging.getLogger(__name__) @six.add_metaclass(abc.ABCMeta)
**** CubicPower OpenStack Study **** class Image(object):
**** CubicPower OpenStack Study **** def __init__(self, source_type, driver_format, is_block_dev=False): """Image initialization. :source_type: block or file :driver_format: raw or qcow2 :is_block_dev: """ self.source_type = source_type self.driver_format = driver_format self.is_block_dev = is_block_dev self.preallocate = False # NOTE(dripton): We store lines of json (path, disk_format) in this # file, for some image types, to prevent attacks based on changing the # disk_format. self.disk_info_path = None # NOTE(mikal): We need a lock directory which is shared along with # instance files, to cover the scenario where multiple compute nodes # are trying to create a base file at the same time self.lock_path = os.path.join(CONF.instances_path, 'locks') @abc.abstractmethod
**** CubicPower OpenStack Study **** def create_image(self, prepare_template, base, size, *args, **kwargs): """Create image from template. Contains specific behavior for each image type. :prepare_template: function, that creates template. Should accept `target` argument. :base: Template name :size: Size of created image in bytes """ pass
**** CubicPower OpenStack Study **** def libvirt_info(self, disk_bus, disk_dev, device_type, cache_mode, extra_specs, hypervisor_version): """Get `LibvirtConfigGuestDisk` filled for this image. :disk_dev: Disk bus device name :disk_bus: Disk bus type :device_type: Device type for this image. :cache_mode: Caching mode for this image :extra_specs: Instance type extra specs dict. """ info = vconfig.LibvirtConfigGuestDisk() info.source_type = self.source_type info.source_device = device_type info.target_bus = disk_bus info.target_dev = disk_dev info.driver_cache = cache_mode info.driver_format = self.driver_format driver_name = libvirt_utils.pick_disk_driver_name(hypervisor_version, self.is_block_dev) info.driver_name = driver_name info.source_path = self.path tune_items = ['disk_read_bytes_sec', 'disk_read_iops_sec', 'disk_write_bytes_sec', 'disk_write_iops_sec', 'disk_total_bytes_sec', 'disk_total_iops_sec'] # Note(yaguang): Currently, the only tuning available is Block I/O # throttling for qemu. if self.source_type in ['file', 'block']: for key, value in extra_specs.iteritems(): scope = key.split(':') if len(scope) > 1 and scope[0] == 'quota': if scope[1] in tune_items: setattr(info, scope[1], value) return info
**** CubicPower OpenStack Study **** def check_image_exists(self): return os.path.exists(self.path)
**** CubicPower OpenStack Study **** def cache(self, fetch_func, filename, size=None, *args, **kwargs): """Creates image from template. Ensures that template and image not already exists. Ensures that base directory exists. Synchronizes on template fetching. :fetch_func: Function that creates the base image Should accept `target` argument. :filename: Name of the file in the image directory :size: Size of created image in bytes (optional) """ @utils.synchronized(filename, external=True, lock_path=self.lock_path) def fetch_func_sync(target, *args, **kwargs): fetch_func(target=target, *args, **kwargs) base_dir = os.path.join(CONF.instances_path, CONF.image_cache_subdirectory_name) if not os.path.exists(base_dir): fileutils.ensure_tree(base_dir) base = os.path.join(base_dir, filename) if not self.check_image_exists() or not os.path.exists(base): self.create_image(fetch_func_sync, base, size, *args, **kwargs) if (size and self.preallocate and self._can_fallocate() and os.access(self.path, os.W_OK)): utils.execute('fallocate', '-n', '-l', size, self.path)
**** CubicPower OpenStack Study **** def fetch_func_sync(target, *args, **kwargs): fetch_func(target=target, *args, **kwargs) base_dir = os.path.join(CONF.instances_path, CONF.image_cache_subdirectory_name) if not os.path.exists(base_dir): fileutils.ensure_tree(base_dir) base = os.path.join(base_dir, filename) if not self.check_image_exists() or not os.path.exists(base): self.create_image(fetch_func_sync, base, size, *args, **kwargs) if (size and self.preallocate and self._can_fallocate() and os.access(self.path, os.W_OK)): utils.execute('fallocate', '-n', '-l', size, self.path)
**** CubicPower OpenStack Study **** def _can_fallocate(self): """Check once per class, whether fallocate(1) is available, and that the instances directory supports fallocate(2). """ can_fallocate = getattr(self.__class__, 'can_fallocate', None) if can_fallocate is None: _out, err = utils.trycmd('fallocate', '-n', '-l', '1', self.path + '.fallocate_test') fileutils.delete_if_exists(self.path + '.fallocate_test') can_fallocate = not err self.__class__.can_fallocate = can_fallocate if not can_fallocate: LOG.error(_('Unable to preallocate_images=%(imgs)s at path: ' '%(path)s'), {'imgs': CONF.preallocate_images, 'path': self.path}) return can_fallocate @staticmethod
**** CubicPower OpenStack Study **** def verify_base_size(base, size, base_size=0): """Check that the base image is not larger than size. Since images can't be generally shrunk, enforce this constraint taking account of virtual image size. """ # Note(pbrady): The size and min_disk parameters of a glance # image are checked against the instance size before the image # is even downloaded from glance, but currently min_disk is # adjustable and doesn't currently account for virtual disk size, # so we need this extra check here. # NOTE(cfb): Having a flavor that sets the root size to 0 and having # nova effectively ignore that size and use the size of the # image is considered a feature at this time, not a bug. if size is None: return if size and not base_size: base_size = disk.get_disk_size(base) if size < base_size: msg = _('%(base)s virtual size %(base_size)s ' 'larger than flavor root disk size %(size)s') LOG.error(msg % {'base': base, 'base_size': base_size, 'size': size}) raise exception.FlavorDiskTooSmall()
**** CubicPower OpenStack Study **** def snapshot_extract(self, target, out_format): raise NotImplementedError()
**** CubicPower OpenStack Study **** def _get_driver_format(self): return self.driver_format
**** CubicPower OpenStack Study **** def resolve_driver_format(self): """Return the driver format for self.path. First checks self.disk_info_path for an entry. If it's not there, calls self._get_driver_format(), and then stores the result in self.disk_info_path See https://bugs.launchpad.net/nova/+bug/1221190 """ def _dict_from_line(line): if not line: return {} try: return jsonutils.loads(line) except (TypeError, ValueError) as e: msg = (_("Could not load line %(line)s, got error " "%(error)s") % {'line': line, 'error': unicode(e)}) raise exception.InvalidDiskInfo(reason=msg) @utils.synchronized(self.disk_info_path, external=False, lock_path=self.lock_path) def write_to_disk_info_file(): # Use os.open to create it without group or world write permission. fd = os.open(self.disk_info_path, os.O_RDWR | os.O_CREAT, 0o644) with os.fdopen(fd, "r+") as disk_info_file: line = disk_info_file.read().rstrip() dct = _dict_from_line(line) if self.path in dct: msg = _("Attempted overwrite of an existing value.") raise exception.InvalidDiskInfo(reason=msg) dct.update({self.path: driver_format}) disk_info_file.seek(0) disk_info_file.truncate() disk_info_file.write('%s\n' % jsonutils.dumps(dct)) # Ensure the file is always owned by the nova user so qemu can't # write it. utils.chown(self.disk_info_path, owner_uid=os.getuid()) try: if (self.disk_info_path is not None and os.path.exists(self.disk_info_path)): with open(self.disk_info_path) as disk_info_file: line = disk_info_file.read().rstrip() dct = _dict_from_line(line) for path, driver_format in dct.iteritems(): if path == self.path: return driver_format driver_format = self._get_driver_format() if self.disk_info_path is not None: fileutils.ensure_tree(os.path.dirname(self.disk_info_path)) write_to_disk_info_file() except OSError as e: raise exception.DiskInfoReadWriteFail(reason=unicode(e)) return driver_format
**** CubicPower OpenStack Study **** def _dict_from_line(line): if not line: return {} try: return jsonutils.loads(line) except (TypeError, ValueError) as e: msg = (_("Could not load line %(line)s, got error " "%(error)s") % {'line': line, 'error': unicode(e)}) raise exception.InvalidDiskInfo(reason=msg) @utils.synchronized(self.disk_info_path, external=False, lock_path=self.lock_path)
**** CubicPower OpenStack Study **** def write_to_disk_info_file(): # Use os.open to create it without group or world write permission. fd = os.open(self.disk_info_path, os.O_RDWR | os.O_CREAT, 0o644) with os.fdopen(fd, "r+") as disk_info_file: line = disk_info_file.read().rstrip() dct = _dict_from_line(line) if self.path in dct: msg = _("Attempted overwrite of an existing value.") raise exception.InvalidDiskInfo(reason=msg) dct.update({self.path: driver_format}) disk_info_file.seek(0) disk_info_file.truncate() disk_info_file.write('%s\n' % jsonutils.dumps(dct)) # Ensure the file is always owned by the nova user so qemu can't # write it. utils.chown(self.disk_info_path, owner_uid=os.getuid()) try: if (self.disk_info_path is not None and os.path.exists(self.disk_info_path)): with open(self.disk_info_path) as disk_info_file: line = disk_info_file.read().rstrip() dct = _dict_from_line(line) for path, driver_format in dct.iteritems(): if path == self.path: return driver_format driver_format = self._get_driver_format() if self.disk_info_path is not None: fileutils.ensure_tree(os.path.dirname(self.disk_info_path)) write_to_disk_info_file() except OSError as e: raise exception.DiskInfoReadWriteFail(reason=unicode(e)) return driver_format
**** CubicPower OpenStack Study **** class Raw(Image):
**** CubicPower OpenStack Study **** def __init__(self, instance=None, disk_name=None, path=None): super(Raw, self).__init__("file", "raw", is_block_dev=False) self.path = (path or os.path.join(libvirt_utils.get_instance_path(instance), disk_name)) self.preallocate = CONF.preallocate_images != 'none' self.disk_info_path = os.path.join(os.path.dirname(self.path), 'disk.info') self.correct_format()
**** CubicPower OpenStack Study **** def _get_driver_format(self): data = images.qemu_img_info(self.path) return data.file_format or 'raw'
**** CubicPower OpenStack Study **** def correct_format(self): if os.path.exists(self.path): self.driver_format = self.resolve_driver_format()
**** CubicPower OpenStack Study **** def create_image(self, prepare_template, base, size, *args, **kwargs): filename = os.path.split(base)[-1] @utils.synchronized(filename, external=True, lock_path=self.lock_path) def copy_raw_image(base, target, size): libvirt_utils.copy_image(base, target) if size: # class Raw is misnamed, format may not be 'raw' in all cases use_cow = self.driver_format == 'qcow2' disk.extend(target, size, use_cow=use_cow) generating = 'image_id' not in kwargs if generating: if not self.check_image_exists(): #Generating image in place prepare_template(target=self.path, *args, **kwargs) else: if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) self.verify_base_size(base, size) if not os.path.exists(self.path): with fileutils.remove_path_on_error(self.path): copy_raw_image(base, self.path, size) self.correct_format()
**** CubicPower OpenStack Study **** def copy_raw_image(base, target, size): libvirt_utils.copy_image(base, target) if size: # class Raw is misnamed, format may not be 'raw' in all cases use_cow = self.driver_format == 'qcow2' disk.extend(target, size, use_cow=use_cow) generating = 'image_id' not in kwargs if generating: if not self.check_image_exists(): #Generating image in place prepare_template(target=self.path, *args, **kwargs) else: if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) self.verify_base_size(base, size) if not os.path.exists(self.path): with fileutils.remove_path_on_error(self.path): copy_raw_image(base, self.path, size) self.correct_format()
**** CubicPower OpenStack Study **** def snapshot_extract(self, target, out_format): images.convert_image(self.path, target, out_format)
**** CubicPower OpenStack Study **** class Qcow2(Image):
**** CubicPower OpenStack Study **** def __init__(self, instance=None, disk_name=None, path=None): super(Qcow2, self).__init__("file", "qcow2", is_block_dev=False) self.path = (path or os.path.join(libvirt_utils.get_instance_path(instance), disk_name)) self.preallocate = CONF.preallocate_images != 'none' self.disk_info_path = os.path.join(os.path.dirname(self.path), 'disk.info') self.resolve_driver_format()
**** CubicPower OpenStack Study **** def create_image(self, prepare_template, base, size, *args, **kwargs): filename = os.path.split(base)[-1] @utils.synchronized(filename, external=True, lock_path=self.lock_path) def copy_qcow2_image(base, target, size): # TODO(pbrady): Consider copying the cow image here # with preallocation=metadata set for performance reasons. # This would be keyed on a 'preallocate_images' setting. libvirt_utils.create_cow_image(base, target) if size: disk.extend(target, size, use_cow=True) # Download the unmodified base image unless we already have a copy. if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) else: self.verify_base_size(base, size) legacy_backing_size = None legacy_base = base # Determine whether an existing qcow2 disk uses a legacy backing by # actually looking at the image itself and parsing the output of the # backing file it expects to be using. if os.path.exists(self.path): backing_path = libvirt_utils.get_disk_backing_file(self.path) if backing_path is not None: backing_file = os.path.basename(backing_path) backing_parts = backing_file.rpartition('_') if backing_file != backing_parts[-1] and \ backing_parts[-1].isdigit(): legacy_backing_size = int(backing_parts[-1]) legacy_base += '_%d' % legacy_backing_size legacy_backing_size *= units.Gi # Create the legacy backing file if necessary. if legacy_backing_size: if not os.path.exists(legacy_base): with fileutils.remove_path_on_error(legacy_base): libvirt_utils.copy_image(base, legacy_base) disk.extend(legacy_base, legacy_backing_size, use_cow=True) if not os.path.exists(self.path): with fileutils.remove_path_on_error(self.path): copy_qcow2_image(base, self.path, size)
**** CubicPower OpenStack Study **** def copy_qcow2_image(base, target, size): # TODO(pbrady): Consider copying the cow image here # with preallocation=metadata set for performance reasons. # This would be keyed on a 'preallocate_images' setting. libvirt_utils.create_cow_image(base, target) if size: disk.extend(target, size, use_cow=True) # Download the unmodified base image unless we already have a copy. if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) else: self.verify_base_size(base, size) legacy_backing_size = None legacy_base = base # Determine whether an existing qcow2 disk uses a legacy backing by # actually looking at the image itself and parsing the output of the # backing file it expects to be using. if os.path.exists(self.path): backing_path = libvirt_utils.get_disk_backing_file(self.path) if backing_path is not None: backing_file = os.path.basename(backing_path) backing_parts = backing_file.rpartition('_') if backing_file != backing_parts[-1] and \ backing_parts[-1].isdigit(): legacy_backing_size = int(backing_parts[-1]) legacy_base += '_%d' % legacy_backing_size legacy_backing_size *= units.Gi # Create the legacy backing file if necessary. if legacy_backing_size: if not os.path.exists(legacy_base): with fileutils.remove_path_on_error(legacy_base): libvirt_utils.copy_image(base, legacy_base) disk.extend(legacy_base, legacy_backing_size, use_cow=True) if not os.path.exists(self.path): with fileutils.remove_path_on_error(self.path): copy_qcow2_image(base, self.path, size)
**** CubicPower OpenStack Study **** def snapshot_extract(self, target, out_format): libvirt_utils.extract_snapshot(self.path, 'qcow2', target, out_format)
**** CubicPower OpenStack Study **** class Lvm(Image): @staticmethod
**** CubicPower OpenStack Study **** def escape(filename): return filename.replace('_', '__')
**** CubicPower OpenStack Study **** def __init__(self, instance=None, disk_name=None, path=None): super(Lvm, self).__init__("block", "raw", is_block_dev=True) if path: info = libvirt_utils.logical_volume_info(path) self.vg = info['VG'] self.lv = info['LV'] self.path = path else: if not CONF.libvirt.images_volume_group: raise RuntimeError(_('You should specify' ' images_volume_group' ' flag to use LVM images.')) self.vg = CONF.libvirt.images_volume_group self.lv = '%s_%s' % (instance['uuid'], self.escape(disk_name)) self.path = os.path.join('/dev', self.vg, self.lv) # TODO(pbrady): possibly deprecate libvirt.sparse_logical_volumes # for the more general preallocate_images self.sparse = CONF.libvirt.sparse_logical_volumes self.preallocate = not self.sparse
**** CubicPower OpenStack Study **** def _can_fallocate(self): return False
**** CubicPower OpenStack Study **** def create_image(self, prepare_template, base, size, *args, **kwargs): filename = os.path.split(base)[-1] @utils.synchronized(filename, external=True, lock_path=self.lock_path) def create_lvm_image(base, size): base_size = disk.get_disk_size(base) self.verify_base_size(base, size, base_size=base_size) resize = size > base_size size = size if resize else base_size libvirt_utils.create_lvm_image(self.vg, self.lv, size, sparse=self.sparse) images.convert_image(base, self.path, 'raw', run_as_root=True) if resize: disk.resize2fs(self.path, run_as_root=True) generated = 'ephemeral_size' in kwargs #Generate images with specified size right on volume if generated and size: libvirt_utils.create_lvm_image(self.vg, self.lv, size, sparse=self.sparse) with self.remove_volume_on_error(self.path): prepare_template(target=self.path, *args, **kwargs) else: if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) with self.remove_volume_on_error(self.path): create_lvm_image(base, size) @contextlib.contextmanager
**** CubicPower OpenStack Study **** def create_lvm_image(base, size): base_size = disk.get_disk_size(base) self.verify_base_size(base, size, base_size=base_size) resize = size > base_size size = size if resize else base_size libvirt_utils.create_lvm_image(self.vg, self.lv, size, sparse=self.sparse) images.convert_image(base, self.path, 'raw', run_as_root=True) if resize: disk.resize2fs(self.path, run_as_root=True) generated = 'ephemeral_size' in kwargs #Generate images with specified size right on volume if generated and size: libvirt_utils.create_lvm_image(self.vg, self.lv, size, sparse=self.sparse) with self.remove_volume_on_error(self.path): prepare_template(target=self.path, *args, **kwargs) else: if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) with self.remove_volume_on_error(self.path): create_lvm_image(base, size) @contextlib.contextmanager
**** CubicPower OpenStack Study **** def remove_volume_on_error(self, path): try: yield except Exception: with excutils.save_and_reraise_exception(): libvirt_utils.remove_logical_volumes(path)
**** CubicPower OpenStack Study **** def snapshot_extract(self, target, out_format): images.convert_image(self.path, target, out_format, run_as_root=True)
**** CubicPower OpenStack Study **** class RBDVolumeProxy(object): """Context manager for dealing with an existing rbd volume. This handles connecting to rados and opening an ioctx automatically, and otherwise acts like a librbd Image object. The underlying librados client and ioctx can be accessed as the attributes 'client' and 'ioctx'. """
**** CubicPower OpenStack Study **** def __init__(self, driver, name, pool=None): client, ioctx = driver._connect_to_rados(pool) try: self.volume = driver.rbd.Image(ioctx, str(name), snapshot=None) except driver.rbd.Error: LOG.exception(_("error opening rbd image %s"), name) driver._disconnect_from_rados(client, ioctx) raise self.driver = driver self.client = client self.ioctx = ioctx
**** CubicPower OpenStack Study **** def __enter__(self): return self
**** CubicPower OpenStack Study **** def __exit__(self, type_, value, traceback): try: self.volume.close() finally: self.driver._disconnect_from_rados(self.client, self.ioctx)
**** CubicPower OpenStack Study **** def __getattr__(self, attrib): return getattr(self.volume, attrib) def ascii_str(s): """Convert a string to ascii, or return None if the input is None. This is useful when a parameter is None by default, or a string. LibRBD only accepts ascii, hence the need for conversion. """ if s is None: return s return str(s)
**** CubicPower OpenStack Study **** def ascii_str(s): """Convert a string to ascii, or return None if the input is None. This is useful when a parameter is None by default, or a string. LibRBD only accepts ascii, hence the need for conversion. """ if s is None: return s return str(s)
**** CubicPower OpenStack Study **** class Rbd(Image):
**** CubicPower OpenStack Study **** def __init__(self, instance=None, disk_name=None, path=None, **kwargs): super(Rbd, self).__init__("block", "rbd", is_block_dev=True) if path: try: self.rbd_name = path.split('/')[1] except IndexError: raise exception.InvalidDevicePath(path=path) else: self.rbd_name = '%s_%s' % (instance['uuid'], disk_name) if not CONF.libvirt.images_rbd_pool: raise RuntimeError(_('You should specify' ' images_rbd_pool' ' flag to use rbd images.')) self.pool = CONF.libvirt.images_rbd_pool self.ceph_conf = ascii_str(CONF.libvirt.images_rbd_ceph_conf) self.rbd_user = ascii_str(CONF.libvirt.rbd_user) self.rbd = kwargs.get('rbd', rbd) self.rados = kwargs.get('rados', rados) self.path = 'rbd:%s/%s' % (self.pool, self.rbd_name) if self.rbd_user: self.path += ':id=' + self.rbd_user if self.ceph_conf: self.path += ':conf=' + self.ceph_conf
**** CubicPower OpenStack Study **** def _connect_to_rados(self, pool=None): client = self.rados.Rados(rados_id=self.rbd_user, conffile=self.ceph_conf) try: client.connect() pool_to_open = str(pool or self.pool) ioctx = client.open_ioctx(pool_to_open) return client, ioctx except self.rados.Error: # shutdown cannot raise an exception client.shutdown() raise
**** CubicPower OpenStack Study **** def _disconnect_from_rados(self, client, ioctx): # closing an ioctx cannot raise an exception ioctx.close() client.shutdown()
**** CubicPower OpenStack Study **** def _supports_layering(self): return hasattr(self.rbd, 'RBD_FEATURE_LAYERING')
**** CubicPower OpenStack Study **** def _ceph_args(self): args = [] if self.rbd_user: args.extend(['--id', self.rbd_user]) if self.ceph_conf: args.extend(['--conf', self.ceph_conf]) return args
**** CubicPower OpenStack Study **** def _get_mon_addrs(self): args = ['ceph', 'mon', 'dump', '--format=json'] + self._ceph_args() out, _ = utils.execute(*args) lines = out.split('\n') if lines[0].startswith('dumped monmap epoch'): lines = lines[1:] monmap = jsonutils.loads('\n'.join(lines)) addrs = [mon['addr'] for mon in monmap['mons']] hosts = [] ports = [] for addr in addrs: host_port = addr[:addr.rindex('/')] host, port = host_port.rsplit(':', 1) hosts.append(host.strip('[]')) ports.append(port) return hosts, ports
**** CubicPower OpenStack Study **** def libvirt_info(self, disk_bus, disk_dev, device_type, cache_mode, extra_specs, hypervisor_version): """Get `LibvirtConfigGuestDisk` filled for this image. :disk_dev: Disk bus device name :disk_bus: Disk bus type :device_type: Device type for this image. :cache_mode: Caching mode for this image :extra_specs: Instance type extra specs dict. """ info = vconfig.LibvirtConfigGuestDisk() hosts, ports = self._get_mon_addrs() info.device_type = device_type info.driver_format = 'raw' info.driver_cache = cache_mode info.target_bus = disk_bus info.target_dev = disk_dev info.source_type = 'network' info.source_protocol = 'rbd' info.source_name = '%s/%s' % (self.pool, self.rbd_name) info.source_hosts = hosts info.source_ports = ports auth_enabled = (CONF.libvirt.rbd_user is not None) if CONF.libvirt.rbd_secret_uuid: info.auth_secret_uuid = CONF.libvirt.rbd_secret_uuid auth_enabled = True # Force authentication locally if CONF.libvirt.rbd_user: info.auth_username = CONF.libvirt.rbd_user if auth_enabled: info.auth_secret_type = 'ceph' info.auth_secret_uuid = CONF.libvirt.rbd_secret_uuid return info
**** CubicPower OpenStack Study **** def _can_fallocate(self): return False
**** CubicPower OpenStack Study **** def check_image_exists(self): rbd_volumes = libvirt_utils.list_rbd_volumes(self.pool) for vol in rbd_volumes: if vol.startswith(self.rbd_name): return True return False
**** CubicPower OpenStack Study **** def _resize(self, volume_name, size): size = int(size) * units.Ki with RBDVolumeProxy(self, volume_name) as vol: vol.resize(size)
**** CubicPower OpenStack Study **** def create_image(self, prepare_template, base, size, *args, **kwargs): if self.rbd is None: raise RuntimeError(_('rbd python libraries not found')) if not os.path.exists(base): prepare_template(target=base, max_size=size, *args, **kwargs) else: self.verify_base_size(base, size) # keep using the command line import instead of librbd since it # detects zeroes to preserve sparseness in the image args = ['--pool', self.pool, base, self.rbd_name] if self._supports_layering(): args += ['--new-format'] args += self._ceph_args() libvirt_utils.import_rbd_image(*args) base_size = disk.get_disk_size(base) if size and size > base_size: self._resize(self.rbd_name, size)
**** CubicPower OpenStack Study **** def snapshot_extract(self, target, out_format): images.convert_image(self.path, target, out_format)
**** CubicPower OpenStack Study **** class Backend(object):
**** CubicPower OpenStack Study **** def __init__(self, use_cow): self.BACKEND = { 'raw': Raw, 'qcow2': Qcow2, 'lvm': Lvm, 'rbd': Rbd, 'default': Qcow2 if use_cow else Raw }
**** CubicPower OpenStack Study **** def backend(self, image_type=None): if not image_type: image_type = CONF.libvirt.images_type image = self.BACKEND.get(image_type) if not image: raise RuntimeError(_('Unknown image_type=%s') % image_type) return image
**** CubicPower OpenStack Study **** def image(self, instance, disk_name, image_type=None): """Constructs image for selected backend :instance: Instance name. :name: Image name. :image_type: Image type. Optional, is CONF.libvirt.images_type by default. """ backend = self.backend(image_type) return backend(instance=instance, disk_name=disk_name)
**** CubicPower OpenStack Study **** def snapshot(self, disk_path, image_type=None): """Returns snapshot for given image :path: path to image :image_type: type of image """ backend = self.backend(image_type) return backend(path=disk_path)
|