virt-manager/virtinst/devicedisk.py

969 lines
31 KiB
Python

#
# Classes for building disk device xml
#
# Copyright 2006-2008, 2012-2014 Red Hat, Inc.
# Jeremy Katz <katzj@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 stat
import pwd
import subprocess
import logging
import re
import urlgrabber.progress as progress
from virtinst import diskbackend
from virtinst import util
from virtinst import VirtualDevice
from virtinst.xmlbuilder import XMLProperty
def _qemu_sanitize_drvtype(phystype, fmt, manual_format=False):
"""
Sanitize libvirt storage volume format to a valid qemu driver type
"""
raw_list = ["iso"]
if phystype == VirtualDisk.TYPE_BLOCK:
if not fmt:
return VirtualDisk.DRIVER_QEMU_RAW
if fmt and not manual_format:
return VirtualDisk.DRIVER_QEMU_RAW
if fmt in raw_list:
return VirtualDisk.DRIVER_QEMU_RAW
return fmt
def _name_uid(user):
"""
Return UID for string username
"""
pwdinfo = pwd.getpwnam(user)
return pwdinfo[2]
def _is_dir_searchable(uid, username, path):
"""
Check if passed directory is searchable by uid
"""
try:
statinfo = os.stat(path)
except OSError:
return False
if uid == statinfo.st_uid:
flag = stat.S_IXUSR
elif uid == statinfo.st_gid:
flag = stat.S_IXGRP
else:
flag = stat.S_IXOTH
if bool(statinfo.st_mode & flag):
return True
# Check POSIX ACL (since that is what we use to 'fix' access)
cmd = ["getfacl", path]
try:
proc = subprocess.Popen(cmd,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = proc.communicate()
except OSError:
logging.debug("Didn't find the getfacl command.")
return False
if proc.returncode != 0:
logging.debug("Cmd '%s' failed: %s", cmd, err)
return False
return bool(re.search("user:%s:..x" % username, out))
def _distill_storage(conn, do_create, nomanaged,
path, vol_object, vol_install,
clone_path, backing_store,
*args):
"""
Validates and updates params when the backing storage is changed
"""
pool = None
path_is_pool = False
storage_capable = conn.check_support(conn.SUPPORT_CONN_STORAGE)
if vol_object:
pass
elif not storage_capable:
pass
elif path and not nomanaged:
path = os.path.abspath(path)
(vol_object, pool, path_is_pool) = diskbackend.manage_path(conn, path)
creator = None
backend = diskbackend.StorageBackend(conn, path, vol_object,
path_is_pool and pool or None)
if not do_create:
return backend, None
if backend.exists(auto_check=False) and path is not None:
if not clone_path:
return backend, None
if path and not (vol_install or pool or clone_path):
raise RuntimeError(_("Don't know how to create storage for "
"path '%s'. Use libvirt APIs to manage the parent directory "
"as a pool first.") % path)
if path or vol_install or pool or clone_path:
creator = diskbackend.StorageCreator(conn, path, pool,
vol_install, clone_path,
backing_store, *args)
return backend, creator
_TARGET_PROPS = ["file", "dev", "dir"]
class VirtualDisk(VirtualDevice):
virtual_device_type = VirtualDevice.VIRTUAL_DEV_DISK
DRIVER_FILE = "file"
DRIVER_PHY = "phy"
DRIVER_TAP = "tap"
DRIVER_QEMU = "qemu"
driver_names = [DRIVER_FILE, DRIVER_PHY, DRIVER_TAP, DRIVER_QEMU]
DRIVER_QEMU_RAW = "raw"
# No list here, since there are many other valid values
DRIVER_TAP_RAW = "aio"
DRIVER_TAP_QCOW = "qcow"
DRIVER_TAP_VMDK = "vmdk"
DRIVER_TAP_VDISK = "vdisk"
driver_types = [DRIVER_TAP_RAW, DRIVER_TAP_QCOW,
DRIVER_TAP_VMDK, DRIVER_TAP_VDISK]
CACHE_MODE_NONE = "none"
CACHE_MODE_WRITETHROUGH = "writethrough"
CACHE_MODE_WRITEBACK = "writeback"
CACHE_MODE_DIRECTSYNC = "directsync"
CACHE_MODE_UNSAFE = "unsafe"
cache_types = [CACHE_MODE_NONE, CACHE_MODE_WRITETHROUGH,
CACHE_MODE_WRITEBACK, CACHE_MODE_DIRECTSYNC, CACHE_MODE_UNSAFE]
DISCARD_MODE_IGNORE = "ignore"
DISCARD_MODE_UNMAP = "unmap"
discard_types = [DISCARD_MODE_IGNORE, DISCARD_MODE_UNMAP]
DEVICE_DISK = "disk"
DEVICE_LUN = "lun"
DEVICE_CDROM = "cdrom"
DEVICE_FLOPPY = "floppy"
devices = [DEVICE_DISK, DEVICE_LUN, DEVICE_CDROM, DEVICE_FLOPPY]
TYPE_FILE = "file"
TYPE_BLOCK = "block"
TYPE_DIR = "dir"
types = [TYPE_FILE, TYPE_BLOCK, TYPE_DIR]
IO_MODE_NATIVE = "native"
IO_MODE_THREADS = "threads"
io_modes = [IO_MODE_NATIVE, IO_MODE_THREADS]
error_policies = ["ignore", "stop", "enospace", "report"]
@staticmethod
def disk_type_to_xen_driver_name(disk_type):
"""
Convert a value of VirtualDisk.type to it's associated Xen
<driver name=/> property
"""
if disk_type == VirtualDisk.TYPE_BLOCK:
return "phy"
elif disk_type == VirtualDisk.TYPE_FILE:
return "file"
return "file"
@staticmethod
def disk_type_to_target_prop(disk_type):
"""
Convert a value of VirtualDisk.type to it's associated XML
target property name
"""
if disk_type == VirtualDisk.TYPE_FILE:
return "file"
elif disk_type == VirtualDisk.TYPE_BLOCK:
return "dev"
elif disk_type == VirtualDisk.TYPE_DIR:
return "dir"
return "file"
@staticmethod
def path_exists(conn, path):
"""
Check if path exists. If we can't determine, return False
"""
if path is None:
return False
try:
(vol, pool, path_is_pool) = diskbackend.check_if_path_managed(
conn, path)
ignore = pool
if vol or path_is_pool:
return True
if not conn.is_remote():
return os.path.exists(path)
except:
pass
return False
@staticmethod
def check_path_search_for_user(conn, path, username):
"""
Check if the passed user has search permissions for all the
directories in the disk path.
@return: List of the directories the user cannot search, or empty list
@rtype : C{list}
"""
if path is None:
return []
if conn.is_remote():
return []
if username == "root":
return []
try:
uid = _name_uid(username)
except Exception, e:
logging.debug("Error looking up username: %s", str(e))
return []
fixlist = []
if os.path.isdir(path):
dirname = path
base = "-"
else:
dirname, base = os.path.split(path)
while base:
if not _is_dir_searchable(uid, username, dirname):
fixlist.append(dirname)
dirname, base = os.path.split(dirname)
return fixlist
@staticmethod
def check_path_search(conn, path):
# Only works for qemu and DAC
if conn.is_remote() or not conn.is_qemu_system():
return None, []
from virtcli import cliconfig
user = cliconfig.default_qemu_user
try:
for i in conn.caps.host.secmodels:
if i.model != "dac":
continue
label = (i.baselabels.get("kvm") or
i.baselabels.get("qemu"))
if not label:
continue
pwuid = pwd.getpwuid(
int(label.split(":")[0].replace("+", "")))
if pwuid:
user = pwuid[0]
except:
logging.debug("Exception grabbing qemu DAC user", exc_info=True)
return None, []
return user, VirtualDisk.check_path_search_for_user(conn, path, user)
@staticmethod
def fix_path_search_for_user(conn, path, username):
"""
Try to fix any permission problems found by check_path_search_for_user
@return: Return a dictionary of entries {broken path : error msg}
@rtype : C{dict}
"""
def fix_perms(dirname, useacl=True):
if useacl:
cmd = ["setfacl", "--modify", "user:%s:x" % username, dirname]
proc = subprocess.Popen(cmd,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = proc.communicate()
logging.debug("Ran command '%s'", cmd)
if out or err:
logging.debug("out=%s\nerr=%s", out, err)
if proc.returncode != 0:
raise ValueError(err)
else:
logging.debug("Setting +x on %s", dirname)
mode = os.stat(dirname).st_mode
newmode = mode | stat.S_IXOTH
os.chmod(dirname, newmode)
if os.stat(dirname).st_mode != newmode:
# Trying to change perms on vfat at least doesn't work
# but also doesn't seem to error. Try and detect that
raise ValueError(_("Permissions on '%s' did not stick") %
dirname)
fixlist = VirtualDisk.check_path_search_for_user(conn, path, username)
if not fixlist:
return []
fixlist.reverse()
errdict = {}
useacl = True
for dirname in fixlist:
try:
try:
fix_perms(dirname, useacl)
except:
# If acl fails, fall back to chmod and retry
if not useacl:
raise
useacl = False
logging.debug("setfacl failed, trying old fashioned way")
fix_perms(dirname, useacl)
except Exception, e:
errdict[dirname] = str(e)
return errdict
@staticmethod
def path_in_use_by(conn, path, shareable=False, read_only=False):
"""
Return a list of VM names that are using the passed path.
@param conn: virConnect to check VMs
@param path: Path to check for
@param shareable: Path we are checking is marked shareable, so
don't warn if it conflicts with another shareable source.
@param read_only: Path we are checking is marked read_only, so
don't warn if it conflicts with another read_only source.
"""
if not path:
return []
# Find all volumes that have 'path' somewhere in their backing chain
vols = []
volmap = dict((vol.backing_store, vol)
for vol in conn.fetch_all_vols() if vol.backing_store)
backpath = path
while backpath in volmap:
vol = volmap[backpath]
if vol in vols:
break
backpath = vol.target_path
vols.append(backpath)
ret = []
vms = conn.fetch_all_guests()
for vm in vms:
if not read_only:
if path in [vm.os.kernel, vm.os.initrd, vm.os.dtb]:
ret.append(vm.name)
continue
for disk in vm.get_devices("disk"):
if disk.path in vols and vm.name not in ret:
# VM uses the path indirectly via backing store
ret.append(vm.name)
break
if disk.path != path:
continue
if shareable and disk.shareable:
continue
if read_only and disk.read_only:
continue
ret.append(vm.name)
break
return ret
@staticmethod
def stat_local_path(path):
"""
Return tuple (storage type, storage size) for the passed path on
the local machine. This is a best effort attempt.
@return: tuple of
(True if regular file, False otherwise, default is True,
max size of storage, default is 0)
"""
try:
return util.stat_disk(path)
except:
return (True, 0)
@staticmethod
def lookup_vol_object(conn, name_tuple):
"""
Return a volume instance from a pool name, vol name tuple
"""
if not conn.check_support(conn.SUPPORT_CONN_STORAGE):
raise ValueError(_("Connection does not support storage lookup."))
try:
pool = conn.storagePoolLookupByName(name_tuple[0])
return pool.storageVolLookupByName(name_tuple[1])
except Exception, e:
raise ValueError(_("Couldn't lookup volume object: %s" % str(e)))
@staticmethod
def build_vol_install(*args, **kwargs):
return diskbackend.build_vol_install(*args, **kwargs)
@staticmethod
def num_to_target(num):
"""
Convert an index in range (1, 1024) to a disk /dev number
(like hda, hdb, hdaa, etc.)
"""
digits = []
for factor in range(0, 3):
amt = (num % (26 ** (factor + 1))) / (26 ** factor)
if amt == 0 and num >= (26 ** (factor + 1)):
amt = 26
num -= amt
digits.insert(0, amt)
seen_valid = False
gen_t = ""
for digit in digits:
if digit == 0:
if not seen_valid:
continue
digit = 1
seen_valid = True
gen_t += "%c" % (ord('a') + digit - 1)
return gen_t
@staticmethod
def target_to_num(tgt):
"""
Convert disk /dev number (like hda, hdb, hdaa, etc.) to an index
"""
num = 0
k = 0
if tgt[0] == 'x':
# This case is here for 'xvda'
tgt = tgt[1:]
for i, c in enumerate(reversed(tgt[2:])):
if i != 0:
k = 1
num += (ord(c) - ord('a') + k) * (26 ** i)
return num
_XML_PROP_ORDER = [
"type", "device",
"driver_name", "driver_type",
"driver_cache", "driver_discard", "driver_io", "error_policy",
"_xmlpath", "target", "bus",
]
def __init__(self, *args, **kwargs):
VirtualDevice.__init__(self, *args, **kwargs)
self.__storage_backend = None
self._storage_creator = None
self.nomanaged = False
self.transient = False
#############################
# Public property-esque API #
#############################
def _get_path(self):
if self._storage_creator:
return self._storage_creator.path
return self._storage_backend.path
def _set_path(self, val):
if self._storage_creator:
raise ValueError("Can't change disk path if storage creation info "
"has been set.")
self._change_backend(val, None)
self._xmlpath = self.path
path = property(_get_path, _set_path)
def get_sparse(self):
if self._storage_creator:
return self._storage_creator.get_sparse()
return None
def get_vol_object(self):
return self._storage_backend.get_vol_object()
def get_vol_install(self):
if not self._storage_creator:
return None
return self._storage_creator.get_vol_install()
def get_size(self):
if self._storage_creator:
return self._storage_creator.get_size()
return self._storage_backend.get_size()
#############################
# Internal defaults helpers #
#############################
def _get_default_type(self):
if self._storage_creator:
return self._storage_creator.get_dev_type()
return self._storage_backend.get_dev_type()
def _get_default_driver_name(self):
if not self.path:
return None
if self.conn.is_qemu():
return self.DRIVER_QEMU
return None
def _get_default_driver_type(self):
"""
Set driver type from passed parameters
Where possible, we want to force /driver/@type = "raw" if installing
a QEMU VM. Without telling QEMU to expect a raw file, the emulator
is forced to autodetect, which has security implications:
http://lists.gnu.org/archive/html/qemu-devel/2008-04/msg00675.html
"""
if self.driver_name != self.DRIVER_QEMU:
return None
if self._storage_creator:
drvtype = self._storage_creator.get_driver_type()
else:
drvtype = self._storage_backend.get_driver_type()
return _qemu_sanitize_drvtype(self.type, drvtype)
##################
# XML properties #
##################
def _make_source_xpath(self):
return "./source/@" + self.disk_type_to_target_prop(self.type)
_xmlpath = XMLProperty(name="disk path",
make_xpath_cb=_make_source_xpath,
clear_first=["./source/@" + target for target in
_TARGET_PROPS])
sourceStartupPolicy = XMLProperty("./source/@startupPolicy")
device = XMLProperty("./@device",
default_cb=lambda s: s.DEVICE_DISK)
type = XMLProperty("./@type", default_cb=_get_default_type)
driver_name = XMLProperty("./driver/@name",
default_cb=_get_default_driver_name)
driver_type = XMLProperty("./driver/@type",
default_cb=_get_default_driver_type)
bus = XMLProperty("./target/@bus")
target = XMLProperty("./target/@dev")
removable = XMLProperty("./target/@removable", is_onoff=True)
read_only = XMLProperty("./readonly", is_bool=True)
shareable = XMLProperty("./shareable", is_bool=True)
driver_cache = XMLProperty("./driver/@cache")
driver_discard = XMLProperty("./driver/@discard")
driver_io = XMLProperty("./driver/@io")
error_policy = XMLProperty("./driver/@error_policy")
serial = XMLProperty("./serial")
iotune_rbs = XMLProperty("./iotune/read_bytes_sec", is_int=True)
iotune_ris = XMLProperty("./iotune/read_iops_sec", is_int=True)
iotune_tbs = XMLProperty("./iotune/total_bytes_sec", is_int=True)
iotune_tis = XMLProperty("./iotune/total_iops_sec", is_int=True)
iotune_wbs = XMLProperty("./iotune/write_bytes_sec", is_int=True)
iotune_wis = XMLProperty("./iotune/write_iops_sec", is_int=True)
#################################
# Validation assistance methods #
#################################
def _get_storage_backend(self):
if self.__storage_backend is None:
self.__storage_backend = diskbackend.StorageBackend(self.conn,
self._xmlpath,
None, None)
return self.__storage_backend
def _set_storage_backend(self, val):
self.__storage_backend = val
_storage_backend = property(_get_storage_backend, _set_storage_backend)
def set_create_storage(self, size=None, sparse=True,
fmt=None, vol_install=None,
clone_path=None, backing_store=None,
fake=False):
"""
Function that sets storage creation parameters. If this isn't
called, we assume that no storage creation is taking place and
will error accordingly.
@size is in gigs
@fake: If true, make like we are creating storage but fail
if we ever asked to do so.
"""
def _validate_path(p):
if p is None:
return
try:
d = VirtualDisk(self.conn)
d.path = p
# If this disk isn't managed, make sure we only perform
# non-managed lookup.
if (self._storage_creator or
(self.path and self._storage_backend.exists())):
d.nomanaged = not self.__managed_storage()
d.set_create_storage(fake=True)
d.validate()
except Exception, e:
raise ValueError(_("Error validating path %s: %s") % (p, e))
path = self.path
# Validate clone_path
if clone_path is not None:
clone_path = os.path.abspath(clone_path)
if backing_store is not None:
backing_store = os.path.abspath(backing_store)
if not fake:
_validate_path(clone_path)
_validate_path(backing_store)
if fake and size is None:
size = .000001
ignore, creator = _distill_storage(
self.conn, True, self.nomanaged, path, None,
vol_install, clone_path, backing_store,
size, sparse, fmt)
self._storage_creator = creator
if self._storage_creator:
self._storage_creator.fake = bool(fake)
self._xmlpath = self.path
else:
if (vol_install or clone_path):
raise RuntimeError("Need storage creation but it "
"didn't happen.")
if fmt and self.driver_name == self.DRIVER_QEMU:
self.driver_type = fmt
def is_cdrom(self):
return self.device == self.DEVICE_CDROM
def is_floppy(self):
return self.device == self.DEVICE_FLOPPY
def is_disk(self):
return self.device == self.DEVICE_DISK
def can_be_empty(self):
return self.is_floppy() or self.is_cdrom()
def _change_backend(self, path, vol_object):
backend, ignore = _distill_storage(
self.conn, False, self.nomanaged,
path, vol_object, None, None, None)
self._storage_backend = backend
def sync_path_props(self):
"""
Fills in the values of type, driver_type, and driver_name for
the associated backing storage. This needs to be manually called
if changing an existing disk's media.
"""
self.type = self._get_default_type()
self.driver_name = self._get_default_driver_name()
self.driver_type = self._get_default_driver_type()
def __managed_storage(self):
"""
Return bool representing if managed storage parameters have
been explicitly specified or filled in
"""
if self._storage_creator:
return self._storage_creator.is_managed()
return self._storage_backend.is_managed()
def creating_storage(self):
"""
Return True if the user requested us to create a device
"""
return bool(self._storage_creator)
def validate(self):
"""
function to validate all the complex interaction between the various
disk parameters.
"""
# No storage specified for a removable device type (CDROM, floppy)
if self.path is None:
if not self.can_be_empty():
raise ValueError(_("Device type '%s' requires a path") %
self.device)
return True
storage_capable = self.conn.check_support(
self.conn.SUPPORT_CONN_STORAGE)
if self.conn.is_remote():
if not storage_capable:
raise ValueError(_("Connection doesn't support remote "
"storage."))
# The main distinctions from this point forward:
# - Are we doing storage API operations or local media checks?
# - Do we need to create the storage?
managed_storage = self.__managed_storage()
create_media = self.creating_storage()
# If not creating the storage, our job is easy
if not create_media:
if not self._storage_backend.exists():
raise ValueError(
_("Must specify storage creation parameters for "
"non-existent path '%s'.") % self.path)
# Make sure we have access to the local path
if not managed_storage:
if (os.path.isdir(self.path) and not self.is_floppy()):
raise ValueError(_("The path '%s' must be a file or a "
"device, not a directory") % self.path)
return True
self._storage_creator.validate(self.device, self.type)
# Applicable for managed or local storage
ret = self.is_size_conflict()
if ret[0]:
raise ValueError(ret[1])
elif ret[1]:
logging.warn(ret[1])
def setup(self, meter=None):
"""
Build storage (if required)
If storage doesn't exist (a non-existent file 'path', or 'vol_install'
was specified), we create it.
@param meter: Progress meter to report file creation on
@type meter: instanceof urlgrabber.BaseMeter
"""
if not meter:
meter = progress.BaseMeter()
if not self._storage_creator:
return
volobj = self._storage_creator.create(meter)
self._storage_creator = None
if volobj:
self._change_backend(None, volobj)
def set_defaults(self, guest):
if self.is_cdrom():
self.read_only = True
if (guest.os.is_xenpv() and
self.type == VirtualDisk.TYPE_FILE and
self.driver_name is None and
util.is_blktap_capable(self.conn)):
self.driver_name = VirtualDisk.DRIVER_TAP
if not self.conn.is_qemu():
return
if not self.is_disk():
return
if not self.type == self.TYPE_BLOCK:
return
# Enable cache=none and io=native for block devices. Would
# be nice if qemu did this for us but that time has long passed.
if not self.driver_cache:
self.driver_cache = self.CACHE_MODE_NONE
if not self.driver_io:
self.driver_io = self.IO_MODE_NATIVE
def is_size_conflict(self):
"""
reports if disk size conflicts with available space
returns a two element tuple:
1. first element is True if fatal conflict occurs
2. second element is a string description of the conflict or None
Non fatal conflicts (sparse disk exceeds available space) will
return (False, "description of collision")
"""
if not self._storage_creator:
return (False, None)
return self._storage_creator.is_size_conflict()
def is_conflict_disk(self, conn=None):
"""
check if specified storage is in use by any other VMs on passed
connection.
@return: list of colliding VM names
@rtype: C{list}
"""
if not self.path:
return False
if not conn:
conn = self.conn
ret = self.path_in_use_by(conn, self.path,
shareable=self.shareable,
read_only=self.read_only)
return ret
def get_target_prefix(self, used_targets=None):
"""
Returns the suggested disk target prefix (hd, xvd, sd ...) for the
disk.
@returns: str prefix, or None if no reasonable guess can be made
"""
# The upper limits here aren't necessarilly 1024, but let the HV
# error as appropriate.
def _return(prefix):
nummap = {
"vd": 1024,
"xvd": 1024,
"fd": 2,
"hd": 4,
"sd": 1024,
}
return prefix, nummap[prefix]
if self.bus == "virtio":
return _return("vd")
elif self.bus == "xen":
return _return("xvd")
elif self.bus == "fdc" or self.is_floppy():
return _return("fd")
elif self.bus == "ide":
return _return("hd")
elif self.bus or not used_targets:
# sata, scsi, usb, sd
return _return("sd")
# If guest already has some disks defined
preforder = ["vd", "xvd", "sd", "hd"]
for pref in preforder:
for target in used_targets:
if target.startswith(pref):
return _return(pref)
return _return("sd")
def generate_target(self, skip_targets, pref_ctrl=None):
"""
Generate target device ('hda', 'sdb', etc..) for disk, excluding
any targets in 'skip_targets'. If given the 'pref_ctrl'
parameter, it tries to select the target so that the disk is
mapped onto that controller.
Sets self.target, and returns the generated value.
@param skip_targets: list of targets to exclude
@type skip_targets: C{list}
@param pref_ctrl: preferred controller to connect the disk to
@type pref_ctrl: C{int}
@raise ValueError: can't determine target type, no targets available
@returns generated target
@rtype C{str}
"""
prefix, maxnode = self.get_target_prefix(skip_targets)
skip_targets = [t for t in skip_targets if t and t.startswith(prefix)]
skip_targets.sort()
def get_target():
first_found = None
ran = range(maxnode)
if pref_ctrl is not None:
# We assume narrow SCSI bus and libvirt assigning 7
# (1-7, 8-14, etc.) devices per controller
ran = range(pref_ctrl * 7, (pref_ctrl + 1) * 7)
for i in ran:
gen_t = prefix + self.num_to_target(i + 1)
if gen_t in skip_targets:
skip_targets.remove(gen_t)
continue
if not skip_targets:
return gen_t
elif not first_found:
first_found = gen_t
if first_found:
return first_found
ret = get_target()
if ret:
self.target = ret
return ret
if pref_ctrl is not None:
# This basically means that we either chose full
# controller or didn't add any
raise ValueError(_("Controller number %d for disk of type %s has "
"no empty slot to use" % (pref_ctrl, prefix)))
else:
raise ValueError(_("Only %s disks of type '%s' are supported"
% (maxnode, prefix)))
VirtualDisk.register_type()