virt-manager/virtinst/storage.py
Cole Robinson 697164f2e5 virtinst: Centralize urlgrabber meter lookup
We will eventually want to drop this dep since it's basically dead
upstream, this is a small step in that direction
2015-09-06 15:09:44 -04:00

875 lines
29 KiB
Python

#
# Copyright 2008, 2013, 2015 Red Hat, Inc.
# Cole Robinson <crobinso@redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301 USA.
import os
import threading
import time
import logging
import libvirt
from .xmlbuilder import XMLBuilder, XMLChildProperty, XMLProperty
from . import util
_DEFAULT_DEV_TARGET = "/dev"
_DEFAULT_LVM_TARGET_BASE = "/dev/"
_DEFAULT_SCSI_TARGET = "/dev/disk/by-path"
_DEFAULT_MPATH_TARGET = "/dev/mapper"
class _StoragePermissions(XMLBuilder):
_XML_ROOT_NAME = "permissions"
_XML_PROP_ORDER = ["mode", "owner", "group", "label"]
mode = XMLProperty("./mode")
owner = XMLProperty("./owner")
group = XMLProperty("./group")
label = XMLProperty("./label")
class _StorageObject(XMLBuilder):
"""
Base class for building any libvirt storage object.
Meaningless to directly instantiate.
"""
######################
# Validation helpers #
######################
def _check_name_collision(self, name):
raise NotImplementedError()
def _validate_name(self, name):
if name == self.name:
return
util.validate_name(_("Storage object"), name)
self._check_name_collision(name)
return name
##############
# Properties #
##############
name = XMLProperty("./name", validate_cb=_validate_name,
doc=_("Name for the storage object."))
permissions = XMLChildProperty(_StoragePermissions,
relative_xpath="./target",
is_single=True)
def _get_default_pool_path(conn):
path = "/var/lib/libvirt/images"
if conn.is_session_uri():
path = os.path.expanduser("~/.local/share/libvirt/images")
return path
class _Host(XMLBuilder):
_XML_PROP_ORDER = ["name", "port"]
_XML_ROOT_NAME = "host"
name = XMLProperty("./@name")
port = XMLProperty("./@port", is_int=True)
class StoragePool(_StorageObject):
"""
Base class for building and installing libvirt storage pool xml
"""
# @group Types: TYPE_*
TYPE_DIR = "dir"
TYPE_FS = "fs"
TYPE_NETFS = "netfs"
TYPE_LOGICAL = "logical"
TYPE_DISK = "disk"
TYPE_ISCSI = "iscsi"
TYPE_SCSI = "scsi"
TYPE_MPATH = "mpath"
TYPE_GLUSTER = "gluster"
TYPE_RBD = "rbd"
TYPE_SHEEPDOG = "sheepdog"
# Pool type descriptions for use in higher level programs
_descs = {}
_descs[TYPE_DIR] = _("Filesystem Directory")
_descs[TYPE_FS] = _("Pre-Formatted Block Device")
_descs[TYPE_NETFS] = _("Network Exported Directory")
_descs[TYPE_LOGICAL] = _("LVM Volume Group")
_descs[TYPE_DISK] = _("Physical Disk Device")
_descs[TYPE_ISCSI] = _("iSCSI Target")
_descs[TYPE_SCSI] = _("SCSI Host Adapter")
_descs[TYPE_MPATH] = _("Multipath Device Enumerator")
_descs[TYPE_GLUSTER] = _("Gluster Filesystem")
_descs[TYPE_RBD] = _("RADOS Block Device/Ceph")
_descs[TYPE_SHEEPDOG] = _("Sheepdog Filesystem")
@staticmethod
def get_pool_types():
"""
Return list of appropriate pool types
"""
return StoragePool._descs.keys()
@staticmethod
def get_pool_type_desc(pool_type):
"""
Return human readable description for passed pool type
"""
return StoragePool._descs.get(pool_type, "%s pool" % pool_type)
@staticmethod
def pool_list_from_sources(conn, pool_type, host=None):
"""
Return a list of StoragePool instances built from libvirt's pool
source enumeration (if supported).
@param conn: Libvirt connection
@param name: Name for the new pool
@param pool_type: Pool type string from I{Types}
@param host: Option host string to poll for sources
"""
if not conn.check_support(conn.SUPPORT_CONN_FINDPOOLSOURCES):
return []
if host:
source_xml = "<source><host name='%s'/></source>" % host
else:
source_xml = "<source/>"
try:
xml = conn.findStoragePoolSources(pool_type, source_xml, 0)
except libvirt.libvirtError, e:
if util.is_error_nosupport(e):
return []
raise
class _EnumerateSource(XMLBuilder):
_XML_ROOT_NAME = "source"
class _EnumerateSources(XMLBuilder):
_XML_ROOT_NAME = "sources"
sources = XMLChildProperty(_EnumerateSource)
ret = []
sources = _EnumerateSources(conn, xml)
for source in sources.sources:
source_xml = source.get_xml_config()
pool_xml = "<pool>\n%s\n</pool>" % (util.xml_indent(source_xml, 2))
parseobj = StoragePool(conn, parsexml=pool_xml)
parseobj.type = pool_type
obj = StoragePool(conn)
obj.type = pool_type
obj.source_path = parseobj.source_path
for host in parseobj.hosts:
parseobj.remove_host(host)
obj.add_host_obj(host)
obj.source_name = parseobj.source_name
obj.format = parseobj.format
ret.append(obj)
return ret
@staticmethod
def build_default_pool(conn):
"""
Helper to build the 'default' storage pool
"""
if not conn.check_support(conn.SUPPORT_CONN_STORAGE):
return
pool = None
name = "default"
path = _get_default_pool_path(conn)
if conn.is_session_uri() and not os.path.exists(path):
os.makedirs(path)
try:
pool = conn.storagePoolLookupByName(name)
except libvirt.libvirtError:
# Try default pool path when "default" name fails
pool = StoragePool.lookup_pool_by_path(conn, path)
if pool:
# This is a libvirt pool object so create a StoragePool from it
return StoragePool(conn, parsexml=pool.XMLDesc(0))
try:
logging.debug("Attempting to build default pool with target '%s'",
path)
defpool = StoragePool(conn)
defpool.type = defpool.TYPE_DIR
defpool.name = name
defpool.target_path = path
defpool.install(build=True, create=True, autostart=True)
conn.clear_cache(pools=True)
return defpool
except Exception, e:
raise RuntimeError(
_("Couldn't create default storage pool '%s': %s") %
(path, str(e)))
@staticmethod
def get_default_dir(conn, build=False):
"""
Return the default storage dir. If there's a 'default' pool,
report that. If there's no default pool, return the dir we would
use for the default.
"""
path = _get_default_pool_path(conn)
if (not conn.is_remote() and
not conn.check_support(conn.SUPPORT_CONN_STORAGE)):
if build and not os.path.exists(path):
os.makedirs(path)
return path
try:
for pool in conn.fetch_all_pools():
if pool.name == "default":
return pool.target_path
except:
pass
if build:
return StoragePool.build_default_pool(conn).target_path
return _get_default_pool_path(conn)
@staticmethod
def lookup_pool_by_path(conn, path):
"""
Return the first pool with matching matching target path.
return the first we find, active or inactive. This iterates over
all pools and dumps their xml, so it is NOT quick.
@returns: virStoragePool object if found, None otherwise
"""
if not conn.check_support(conn.SUPPORT_CONN_STORAGE):
return None
for pool in conn.fetch_all_pools():
xml_path = pool.target_path
if xml_path is not None and os.path.abspath(xml_path) == path:
return conn.storagePoolLookupByName(pool.name)
return None
@staticmethod
def find_free_name(conn, basename, **kwargs):
"""
Finds a name similar (or equal) to passed 'basename' that is not
in use by another pool. Extra params are passed to generate_name
"""
return util.generate_name(basename,
conn.storagePoolLookupByName,
**kwargs)
def __init__(self, *args, **kwargs):
_StorageObject.__init__(self, *args, **kwargs)
self._random_uuid = None
######################
# Validation helpers #
######################
def _check_name_collision(self, name):
pool = None
try:
pool = self.conn.storagePoolLookupByName(name)
except libvirt.libvirtError:
pass
if pool:
raise ValueError(_("Name '%s' already in use by another pool." %
name))
def _get_default_target_path(self):
if not self.supports_property("target_path"):
return None
if (self.type == self.TYPE_DIR or
self.type == self.TYPE_NETFS or
self.type == self.TYPE_FS):
return os.path.join(self.get_default_dir(self.conn), self.name)
if self.type == self.TYPE_LOGICAL:
name = self.name
if self.source_name:
name = self.source_name
return _DEFAULT_LVM_TARGET_BASE + name
if self.type == self.TYPE_DISK:
return _DEFAULT_DEV_TARGET
if self.type == self.TYPE_ISCSI or self.type == self.TYPE_SCSI:
return _DEFAULT_SCSI_TARGET
if self.type == self.TYPE_MPATH:
return _DEFAULT_MPATH_TARGET
raise RuntimeError("No default target_path for type=%s" % self.type)
def _get_default_uuid(self):
if self._random_uuid is None:
self._random_uuid = util.generate_uuid(self.conn)
return self._random_uuid
def _type_to_source_prop(self):
if (self.type == self.TYPE_NETFS or
self.type == self.TYPE_GLUSTER):
return "_source_dir"
elif self.type == self.TYPE_SCSI:
return "_source_adapter"
else:
return "_source_device"
def _get_source(self):
return getattr(self, self._type_to_source_prop())
def _set_source(self, val):
return setattr(self, self._type_to_source_prop(), val)
source_path = property(_get_source, _set_source)
def _default_source_name(self):
if not self.supports_property("source_name"):
return None
if self.type == StoragePool.TYPE_NETFS:
srcname = self.name
elif self.type == StoragePool.TYPE_RBD:
srcname = "rbd"
elif self.type == StoragePool.TYPE_GLUSTER:
srcname = "gv0"
elif ("target_path" in self._propstore and
self.target_path and
self.target_path.startswith(_DEFAULT_LVM_TARGET_BASE)):
# If there is a target path, parse it for an expected VG
# location, and pull the name from there
vg = self.target_path[len(_DEFAULT_LVM_TARGET_BASE):]
srcname = vg.split("/", 1)[0]
return srcname
def _default_format_cb(self):
if not self.supports_property("format"):
return None
return "auto"
##############
# Properties #
##############
_XML_ROOT_NAME = "pool"
_XML_PROP_ORDER = ["name", "type", "uuid",
"capacity", "allocation", "available",
"format", "hosts",
"_source_dir", "_source_adapter", "_source_device",
"source_name", "target_path",
"permissions"]
_source_dir = XMLProperty("./source/dir/@path")
_source_adapter = XMLProperty("./source/adapter/@name")
_source_device = XMLProperty("./source/device/@path")
type = XMLProperty("./@type",
doc=_("Storage device type the pool will represent."))
uuid = XMLProperty("./uuid",
validate_cb=lambda s, v: util.validate_uuid(v),
default_cb=_get_default_uuid)
capacity = XMLProperty("./capacity", is_int=True)
allocation = XMLProperty("./allocation", is_int=True)
available = XMLProperty("./available", is_int=True)
format = XMLProperty("./source/format/@type",
default_cb=_default_format_cb)
iqn = XMLProperty("./source/initiator/iqn/@name",
doc=_("iSCSI initiator qualified name"))
source_name = XMLProperty("./source/name",
default_cb=_default_source_name,
doc=_("Name of the Volume Group"))
target_path = XMLProperty("./target/path",
default_cb=_get_default_target_path)
def add_host_obj(self, obj):
self.add_child(obj)
def add_host(self, name, port=None):
obj = _Host(self.conn)
obj.name = name
obj.port = port
self.add_child(obj)
def remove_host(self, obj):
self.remove_child(obj)
hosts = XMLChildProperty(_Host, relative_xpath="./source")
######################
# Public API helpers #
######################
def supports_property(self, propname):
users = {
"source_path": [self.TYPE_FS, self.TYPE_NETFS, self.TYPE_LOGICAL,
self.TYPE_DISK, self.TYPE_ISCSI, self.TYPE_SCSI,
self.TYPE_GLUSTER],
"source_name": [self.TYPE_LOGICAL, self.TYPE_GLUSTER,
self.TYPE_RBD, self.TYPE_SHEEPDOG],
"hosts": [self.TYPE_NETFS, self.TYPE_ISCSI, self.TYPE_GLUSTER,
self.TYPE_RBD, self.TYPE_SHEEPDOG],
"format": [self.TYPE_FS, self.TYPE_NETFS, self.TYPE_DISK],
"iqn": [self.TYPE_ISCSI],
"target_path" : [self.TYPE_DIR, self.TYPE_FS, self.TYPE_NETFS,
self.TYPE_LOGICAL, self.TYPE_DISK, self.TYPE_ISCSI,
self.TYPE_SCSI, self.TYPE_MPATH]
}
if users.get(propname):
return self.type in users[propname]
return hasattr(self, propname)
def list_formats(self):
if self.type == self.TYPE_FS:
return ["auto", "ext2", "ext3", "ext4", "ufs", "iso9660", "udf",
"gfs", "gfs2", "vfat", "hfs+", "xfs"]
if self.type == self.TYPE_NETFS:
return ["auto", "nfs", "glusterfs"]
if self.type == self.TYPE_DISK:
return ["auto", "bsd", "dos", "dvh", "gpt", "mac", "pc98", "sun"]
return []
def supports_volume_creation(self):
return self.type in [
StoragePool.TYPE_DIR, StoragePool.TYPE_FS,
StoragePool.TYPE_NETFS, StoragePool.TYPE_LOGICAL,
StoragePool.TYPE_DISK,
StoragePool.TYPE_RBD, StoragePool.TYPE_SHEEPDOG]
##################
# Build routines #
##################
def validate(self):
if self.supports_property("host") and not self.hosts:
raise RuntimeError(_("Hostname is required"))
if (self.supports_property("source_path") and
not self.type == self.TYPE_LOGICAL and
not self.source_path):
raise RuntimeError(_("Source path is required"))
if (self.type == self.TYPE_DISK and self.format == "auto"):
# There is no explicit "auto" type for disk pools, but leaving out
# the format type seems to do the job for existing formatted disks
self.format = None
def install(self, meter=None, create=False, build=False, autostart=False):
"""
Install storage pool xml.
"""
if (self.type == self.TYPE_LOGICAL and
build and not self.source_path):
raise ValueError(_("Must explicitly specify source path if "
"building pool"))
if (self.type == self.TYPE_DISK and
build and self.format == "auto"):
raise ValueError(_("Must explicitly specify disk format if "
"formatting disk device."))
xml = self.get_xml_config()
logging.debug("Creating storage pool '%s' with xml:\n%s",
self.name, xml)
meter = util.ensure_meter(meter)
try:
pool = self.conn.storagePoolDefineXML(xml, 0)
except Exception, e:
raise RuntimeError(_("Could not define storage pool: %s") % str(e))
errmsg = None
if build:
try:
pool.build(libvirt.VIR_STORAGE_POOL_BUILD_NEW)
except Exception, e:
errmsg = _("Could not build storage pool: %s") % str(e)
if create and not errmsg:
try:
pool.create(0)
except Exception, e:
errmsg = _("Could not start storage pool: %s") % str(e)
if autostart and not errmsg:
try:
pool.setAutostart(True)
except Exception, e:
errmsg = _("Could not set pool autostart flag: %s") % str(e)
if errmsg:
# Try and clean up the leftover pool
try:
pool.undefine()
except Exception, e:
logging.debug("Error cleaning up pool after failure: " +
"%s" % str(e))
raise RuntimeError(errmsg)
return pool
class StorageVolume(_StorageObject):
"""
Base class for building and installing libvirt storage volume xml
"""
ALL_FORMATS = ["raw", "bochs", "cloop", "cow", "dmg", "iso", "qcow",
"qcow2", "qed", "vmdk", "vpc", "fat", "vhd", "vdi"]
@staticmethod
def get_file_extension_for_format(fmt):
if not fmt:
return ""
if fmt == "raw":
return ".img"
return "." + fmt
@staticmethod
def find_free_name(pool_object, basename, **kwargs):
"""
Finds a name similar (or equal) to passed 'basename' that is not
in use by another volume. Extra params are passed to generate_name
"""
pool_object.refresh(0)
return util.generate_name(basename,
pool_object.storageVolLookupByName,
**kwargs)
TYPE_FILE = getattr(libvirt, "VIR_STORAGE_VOL_FILE", 0)
TYPE_BLOCK = getattr(libvirt, "VIR_STORAGE_VOL_BLOCK", 1)
TYPE_DIR = getattr(libvirt, "VIR_STORAGE_VOL_DIR", 2)
TYPE_NETWORK = getattr(libvirt, "VIR_STORAGE_VOL_NETWORK", 3)
TYPE_NETDIR = getattr(libvirt, "VIR_STORAGE_VOL_NETDIR", 4)
def __init__(self, *args, **kwargs):
_StorageObject.__init__(self, *args, **kwargs)
self._input_vol = None
self._pool = None
self._pool_xml = None
self._reflink = False
# Indicate that the volume installation has finished. Used to
# definitively tell the storage progress thread to stop polling.
self._install_finished = True
######################
# Non XML properties #
######################
def _get_pool(self):
return self._pool
def _set_pool(self, newpool):
if newpool.info()[0] != libvirt.VIR_STORAGE_POOL_RUNNING:
raise ValueError(_("pool '%s' must be active.") % newpool.name())
self._pool = newpool
self._pool_xml = StoragePool(self.conn,
parsexml=self._pool.XMLDesc(0))
pool = property(_get_pool, _set_pool)
def _get_input_vol(self):
return self._input_vol
def _set_input_vol(self, vol):
if vol is None:
self._input_vol = None
return
if not isinstance(vol, libvirt.virStorageVol):
raise ValueError(_("input_vol must be a virStorageVol"))
if not self.conn.check_support(
self.conn.SUPPORT_POOL_CREATEVOLFROM, self.pool):
raise ValueError(_("Creating storage from an existing volume is"
" not supported by this libvirt version."))
self._input_vol = vol
input_vol = property(_get_input_vol, _set_input_vol,
doc=_("virStorageVolume pointer to clone/use as "
"input."))
def _get_reflink(self):
return self._reflink
def _set_reflink(self, reflink):
if (reflink and not
self.conn.check_support(self.conn.SUPPORT_POOL_REFLINK)):
raise ValueError(_("Creating storage by btrfs COW copy is"
" not supported by this libvirt version."))
self._reflink = reflink
reflink = property(_get_reflink, _set_reflink,
doc="flags for VIR_STORAGE_VOL_CREATE_REFLINK")
def sync_input_vol(self, only_format=False):
# Pull parameters from input vol into this class
parsevol = StorageVolume(self.conn,
parsexml=self._input_vol.XMLDesc(0))
self.format = parsevol.format
self.capacity = parsevol.capacity
self.allocation = parsevol.allocation
if only_format:
return
self.pool = self._input_vol.storagePoolLookupByVolume()
##########################
# XML validation helpers #
##########################
def _check_name_collision(self, name):
vol = None
try:
vol = self.pool.storageVolLookupByName(name)
except libvirt.libvirtError:
pass
if vol:
raise ValueError(_("Name '%s' already in use by another volume." %
name))
def _validate_allocation(self, val):
ret = self.is_size_conflict(allocation=val)
if ret[0]:
raise ValueError(ret[1])
elif ret[1]:
logging.warn(ret[1])
return val
def _validate_capacity(self, val):
ret = self.is_size_conflict(capacity=val)
if ret[0]:
raise ValueError(ret[1])
elif ret[1]:
logging.warn(ret[1])
return val
def _default_format(self):
if self.file_type == self.TYPE_FILE:
return "raw"
return None
def _get_vol_type(self):
if self.type:
return self.type
if (self._pool_xml.type == StoragePool.TYPE_DISK or
self._pool_xml.type == StoragePool.TYPE_LOGICAL):
return self.TYPE_BLOCK
if (self._pool_xml.type == StoragePool.TYPE_GLUSTER or
self._pool_xml.type == StoragePool.TYPE_RBD or
self._pool_xml.type == StoragePool.TYPE_SHEEPDOG):
return self.TYPE_NETWORK
return self.TYPE_FILE
file_type = property(_get_vol_type)
##################
# XML properties #
##################
_XML_ROOT_NAME = "volume"
_XML_PROP_ORDER = ["name", "key", "capacity", "allocation", "format",
"target_path", "permissions"]
type = XMLProperty("./@type")
key = XMLProperty("./key")
capacity = XMLProperty("./capacity", is_int=True,
validate_cb=_validate_capacity)
allocation = XMLProperty("./allocation", is_int=True,
validate_cb=_validate_allocation)
format = XMLProperty("./target/format/@type", default_cb=_default_format)
target_path = XMLProperty("./target/path")
backing_store = XMLProperty("./backingStore/path")
def _lazy_refcounts_default_cb(self):
if self.format != "qcow2":
return False
return self.conn.check_support(
self.conn.SUPPORT_CONN_QCOW2_LAZY_REFCOUNTS)
lazy_refcounts = XMLProperty("./target/features/lazy_refcounts",
is_bool=True, default_cb=_lazy_refcounts_default_cb)
######################
# Public API helpers #
######################
def _supports_format(self):
if self.file_type == self.TYPE_FILE:
return True
if self._pool_xml.type == StoragePool.TYPE_GLUSTER:
return True
return False
def supports_property(self, propname):
if propname == "format":
return self._supports_format()
return hasattr(self, propname)
def list_formats(self):
if self._supports_format():
return self.ALL_FORMATS
return []
def list_create_formats(self):
if self._supports_format():
return ["raw", "cow", "qcow", "qcow2", "qed", "vmdk", "vpc", "vdi"]
return None
##################
# Build routines #
##################
def validate(self):
if self._pool_xml.type == StoragePool.TYPE_LOGICAL:
if self.allocation != self.capacity:
logging.warn(_("Sparse logical volumes are not supported, "
"setting allocation equal to capacity"))
self.allocation = self.capacity
def install(self, meter=None):
"""
Build and install storage volume from xml
"""
xml = self.get_xml_config()
logging.debug("Creating storage volume '%s' with xml:\n%s",
self.name, xml)
t = threading.Thread(target=self._progress_thread,
name="Checking storage allocation",
args=(meter,))
t.setDaemon(True)
meter = util.ensure_meter(meter)
cloneflags = 0
createflags = 0
if (self.format == "qcow2" and
not self.backing_store and
not self.conn.is_really_test() and
self.conn.check_support(
self.conn.SUPPORT_POOL_METADATA_PREALLOC, self.pool)):
createflags |= libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA
if self.reflink:
cloneflags |= getattr(libvirt,
"VIR_STORAGE_VOL_CREATE_REFLINK", 1)
try:
self._install_finished = False
t.start()
meter.start(size=self.capacity,
text=_("Allocating '%s'") % self.name)
if self.input_vol:
vol = self.pool.createXMLFrom(xml, self.input_vol, cloneflags)
else:
logging.debug("Using vol create flags=%s", createflags)
vol = self.pool.createXML(xml, createflags)
self._install_finished = True
t.join()
meter.end(self.capacity)
logging.debug("Storage volume '%s' install complete.",
self.name)
return vol
except Exception, e:
logging.debug("Error creating storage volume", exc_info=True)
raise RuntimeError("Couldn't create storage volume "
"'%s': '%s'" % (self.name, str(e)))
def _progress_thread(self, meter):
lookup_attempts = 10
vol = None
if not meter:
return
while lookup_attempts > 0:
try:
if not vol:
vol = self.pool.storageVolLookupByName(self.name)
vol.info()
break
except:
lookup_attempts -= 1
time.sleep(.2)
if self._install_finished:
break
else:
continue
break
if vol is None:
logging.debug("Couldn't lookup storage volume in prog thread.")
return
while not self._install_finished:
ignore, ignore, alloc = vol.info()
meter.update(alloc)
time.sleep(1)
def is_size_conflict(self, capacity=None, allocation=None):
"""
Report if requested size exceeds its pool's available amount
@returns: 2 element tuple:
1. True if collision is fatal, false otherwise
2. String message if some collision was encountered.
@rtype: 2 element C{tuple}: (C{bool}, C{str})
"""
if capacity is None:
capacity = self.capacity
if allocation is None:
allocation = self.allocation
if not self.pool:
return (False, "")
# pool info is [pool state, capacity, allocation, available]
avail = self.pool.info()[3]
if allocation > avail:
return (True, _("There is not enough free space on the storage "
"pool to create the volume. "
"(%d M requested allocation > %d M available)" %
((allocation / (1024 * 1024)),
(avail / (1024 * 1024)))))
elif capacity > avail:
return (False, _("The requested volume capacity will exceed the "
"available pool space when the volume is fully "
"allocated. "
"(%d M requested capacity > %d M available)" %
((capacity / (1024 * 1024)),
(avail / (1024 * 1024)))))
return (False, "")