Current File : //usr/share/virt-manager/virtinst/devicedisk.py
#
# 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
from . import diskbackend
from . import util
from .device import VirtualDevice
from .xmlbuilder import XMLBuilder, XMLChildProperty, 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_TYPE_RAW
if fmt and not manual_format:
return VirtualDisk.DRIVER_TYPE_RAW
if fmt in raw_list:
return VirtualDisk.DRIVER_TYPE_RAW
return fmt
def _is_dir_searchable(uid, username, path):
"""
Check if passed directory is searchable by uid
"""
if "VIRTINST_TEST_SUITE" in os.environ:
return True
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))
class _Host(XMLBuilder):
_XML_PROP_ORDER = ["name", "port"]
_XML_ROOT_NAME = "host"
name = XMLProperty("./@name")
port = XMLProperty("./@port", is_int=True)
class _DiskSeclabel(XMLBuilder):
"""
This is for disk source <seclabel>. It's similar to a domain
<seclabel> but has fewer options
"""
_XML_ROOT_NAME = "seclabel"
model = XMLProperty("./@model")
relabel = XMLProperty("./@relabel", is_yesno=True)
label = XMLProperty("./label")
class VirtualDisk(VirtualDevice):
virtual_device_type = VirtualDevice.VIRTUAL_DEV_DISK
DRIVER_NAME_PHY = "phy"
DRIVER_NAME_QEMU = "qemu"
DRIVER_TYPE_RAW = "raw"
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"
TYPE_VOLUME = "volume"
TYPE_NETWORK = "network"
types = [TYPE_FILE, TYPE_BLOCK, TYPE_DIR, TYPE_NETWORK]
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 pretty_disk_bus(bus):
if bus in ["ide", "sata", "scsi", "usb", "sd"]:
return bus.upper()
if bus in ["xen"]:
return bus.capitalize()
if bus == "virtio":
return "VirtIO"
return bus
@staticmethod
def path_definitely_exists(conn, path):
"""
Check if path exists.
return True if we are certain, False otherwise. Path may in fact
exist if we return False, but we can't exhaustively know in all
cases.
(In fact if cached storage volume data is out of date, the volume
may have disappeared behind our back, but that shouldn't have bad
effects in practice.)
"""
if path is None:
return False
try:
(vol, pool) = diskbackend.check_if_path_managed(conn, path)
ignore = pool
if vol:
return True
if not conn.is_remote():
return os.path.exists(path)
except Exception:
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 []
if diskbackend.path_is_url(path):
return []
try:
# Get UID for string name
uid = pwd.getpwnam(username)[2]
except Exception as 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 secmodel in conn.caps.host.secmodels:
if secmodel.model != "dac":
continue
label = None
for baselabel in secmodel.baselabels:
if baselabel.type in ["qemu", "kvm"]:
label = baselabel.content
break
if not label:
continue
pwuid = pwd.getpwuid(
int(label.split(":")[0].replace("+", "")))
if pwuid:
user = pwuid[0]
except Exception:
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 Exception:
# 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 as 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 build_vol_install(conn, volname, poolobj, size, sparse,
fmt=None, backing_store=None, backing_format=None):
"""
Helper for building a StorageVolume instance to pass to VirtualDisk
for eventual storage creation.
:param volname: name of the volume to be created
:param size: size in bytes
"""
from .storage import StorageVolume
if size is None:
raise ValueError(_("Size must be specified for non "
"existent volume '%s'" % volname))
# This catches --disk /dev/idontexist,size=1 if /dev is unmanaged
if not poolobj:
raise RuntimeError(_("Don't know how to create storage for "
"path '%s'. Use libvirt APIs to manage the parent directory "
"as a pool first.") % volname)
logging.debug("Creating volume '%s' on pool '%s'",
volname, poolobj.name())
cap = (size * 1024 * 1024 * 1024)
if sparse:
alloc = 0
else:
alloc = cap
volinst = StorageVolume(conn)
volinst.pool = poolobj
volinst.name = volname
volinst.capacity = cap
volinst.allocation = alloc
volinst.backing_store = backing_store
volinst.backing_format = backing_format
if fmt:
if not volinst.supports_property("format"):
raise ValueError(_("Format attribute not supported for this "
"volume type"))
volinst.format = fmt
return volinst
@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", "snapshot_policy",
"driver_name", "driver_type",
"driver_cache", "driver_discard", "driver_detect_zeroes",
"driver_io", "error_policy",
"_source_file", "_source_dev", "_source_dir",
"auth_username", "auth_secret_type", "auth_secret_uuid",
"source_volume", "source_pool", "source_protocol", "source_name",
"source_host_name", "source_host_port",
"source_host_transport", "source_host_socket",
"target", "bus",
]
def __init__(self, *args, **kwargs):
VirtualDevice.__init__(self, *args, **kwargs)
self._source_volume_err = None
self._storage_backend = None
self.storage_was_created = False
#############################
# Public property-esque API #
#############################
def _get_path(self):
if not self._storage_backend:
xmlpath = self._get_xmlpath()
if xmlpath:
return xmlpath
self._set_default_storage_backend()
return self._storage_backend.get_path()
def _set_path(self, newpath):
if (self._storage_backend and
self._storage_backend.will_create_storage()):
raise ValueError(_("Can't change disk path if storage creation info "
"has been set."))
# User explicitly changed 'path', so try to lookup its storage
# object since we may need it
(vol_object, parent_pool) = diskbackend.manage_path(self.conn, newpath)
self._change_backend(newpath, vol_object, parent_pool)
self._set_xmlpath(self.path)
path = property(_get_path, _set_path)
def set_vol_object(self, vol_object, parent_pool):
logging.debug("disk.set_vol_object: volxml=\n%s",
vol_object.XMLDesc(0))
logging.debug("disk.set_vol_object: poolxml=\n%s",
parent_pool.XMLDesc(0))
self._change_backend(None, vol_object, parent_pool)
self._set_xmlpath(self.path)
def set_vol_install(self, vol_install):
logging.debug("disk.set_vol_install: name=%s poolxml=\n%s",
vol_install.name, vol_install.pool.XMLDesc(0))
self._storage_backend = diskbackend.ManagedStorageCreator(
self.conn, vol_install)
self._set_xmlpath(self.path)
def get_vol_object(self):
return self._storage_backend.get_vol_object()
def get_vol_install(self):
return self._storage_backend.get_vol_install()
def get_parent_pool(self):
if self.get_vol_install():
return self.get_vol_install().pool
return self._storage_backend.get_parent_pool()
def get_size(self):
return self._storage_backend.get_size()
#############################
# Internal defaults helpers #
#############################
def _get_default_driver_name(self):
if not self.path:
return None
# Recommended xen defaults from here:
# https://bugzilla.redhat.com/show_bug.cgi?id=1171550#c9
# If type block, use name=phy. Otherwise do the same as qemu
if self.conn.is_xen() and self.type == self.TYPE_BLOCK:
return self.DRIVER_NAME_PHY
if self.conn.check_support(
self.conn.SUPPORT_CONN_DISK_DRIVER_NAME_QEMU):
return self.DRIVER_NAME_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_NAME_QEMU:
return None
drvtype = self._storage_backend.get_driver_type()
return _qemu_sanitize_drvtype(self.type, drvtype)
#############################
# XML source media handling #
#############################
_source_file = XMLProperty("./source/@file")
_source_dev = XMLProperty("./source/@dev")
_source_dir = XMLProperty("./source/@dir")
source_pool = XMLProperty("./source/@pool")
source_volume = XMLProperty("./source/@volume")
auth_username = XMLProperty("./auth/@username")
auth_secret_type = XMLProperty("./auth/secret/@type")
auth_secret_uuid = XMLProperty("./auth/secret/@uuid")
def add_host(self, name, port):
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")
source_name = XMLProperty("./source/@name")
source_protocol = XMLProperty("./source/@protocol")
# Technically multiple host lines can be listed
source_host_name = XMLProperty("./source/host/@name")
source_host_port = XMLProperty("./source/host/@port", is_int=True)
source_host_transport = XMLProperty("./source/host/@transport")
source_host_socket = XMLProperty("./source/host/@socket")
def _set_source_network_from_url(self, uri):
from .uri import URI
uriobj = URI(uri)
if uriobj.scheme:
self.source_protocol = uriobj.scheme
if uriobj.transport:
self.source_host_transport = uriobj.transport
if uriobj.hostname:
self.source_host_name = uriobj.hostname
if uriobj.port:
self.source_host_port = uriobj.port
if uriobj.path:
if self.source_host_transport:
self.source_host_socket = uriobj.path
else:
self.source_name = uriobj.path
if self.source_name.startswith("/"):
self.source_name = self.source_name[1:]
def _set_source_network_from_storage(self, volxml, poolxml):
self.source_protocol = poolxml.type
logging.debug("disk.set_vol_object: poolxml=\n%s",
dir(poolxml))
if poolxml.auth_type:
self.auth_username = poolxml.auth_username
self.auth_secret_type = poolxml.auth_type
self.auth_secret_uuid = poolxml.auth_secret_uuid
if poolxml.hosts:
self.source_host_name = poolxml.hosts[0].name
self.source_host_port = poolxml.hosts[0].port
for host in poolxml.hosts:
self.add_host(host.name, host.port)
path = ""
if poolxml.source_name:
path += poolxml.source_name
if poolxml.source_path:
path += poolxml.source_path
if not path.endswith('/'):
path += "/"
path += volxml.name
self.source_name = path
self.type = "network"
def _set_network_source_from_backend(self):
if (self._storage_backend.get_vol_object() or
self._storage_backend.get_vol_install()):
volxml = self._storage_backend.get_vol_xml()
poolxml = self._storage_backend.get_parent_pool_xml()
self._set_source_network_from_storage(volxml, poolxml)
elif self._storage_backend.get_path():
self._set_source_network_from_url(self._storage_backend.get_path())
def _build_url_from_network_source(self):
ret = self.source_protocol
if self.source_host_transport:
ret += "+%s" % self.source_host_transport
ret += "://"
if self.source_host_name:
ret += self.source_host_name
if self.source_host_port:
ret += ":" + str(self.source_host_port)
if self.source_name:
if not self.source_name.startswith("/"):
ret += "/"
ret += self.source_name
elif self.source_host_socket:
if not self.source_host_socket.startswith("/"):
ret += "/"
ret += self.source_host_socket
return ret
def _get_default_type(self):
if self.source_pool or self.source_volume:
return VirtualDisk.TYPE_VOLUME
if self._storage_backend:
return self._storage_backend.get_dev_type()
if self.source_protocol:
return VirtualDisk.TYPE_NETWORK
return self.TYPE_FILE
type = XMLProperty("./@type", default_cb=_get_default_type)
def _clear_source_xml(self):
"""
Unset all XML properties that describe the actual source media
"""
self._source_file = None
self._source_dev = None
self._source_dir = None
self.source_volume = None
self.source_pool = None
self.source_name = None
self.source_protocol = None
self.source_host_name = None
self.source_host_port = None
self.source_host_transport = None
self.source_host_socket = None
def _disk_type_to_object_prop_name(self):
disk_type = self.type
if disk_type == VirtualDisk.TYPE_BLOCK:
return "_source_dev"
elif disk_type == VirtualDisk.TYPE_DIR:
return "_source_dir"
elif disk_type == VirtualDisk.TYPE_FILE:
return "_source_file"
return None
# _xmlpath is an abstraction for source file/block/dir paths, since
# they don't have any special properties aside from needing to match
# 'type' value with the source property used.
def _get_xmlpath(self):
if self._source_file:
return self._source_file
if self._source_dev:
return self._source_dev
if self._source_dir:
return self._source_dir
return None
def _set_xmlpath(self, val):
self._clear_source_xml()
if self._storage_backend.get_dev_type() == "network":
self._set_network_source_from_backend()
return
propname = self._disk_type_to_object_prop_name()
if not propname:
return
return setattr(self, propname, val)
##################
# XML properties #
##################
device = XMLProperty("./@device",
default_cb=lambda s: s.DEVICE_DISK)
snapshot_policy = XMLProperty("./@snapshot")
driver_name = XMLProperty("./driver/@name",
default_cb=_get_default_driver_name)
driver_type = XMLProperty("./driver/@type",
default_cb=_get_default_driver_type)
sgio = XMLProperty("./@sgio")
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_detect_zeroes = XMLProperty("./driver/@detect_zeroes")
driver_io = XMLProperty("./driver/@io")
error_policy = XMLProperty("./driver/@error_policy")
serial = XMLProperty("./serial")
startup_policy = XMLProperty("./source/@startupPolicy")
logical_block_size = XMLProperty("./blockio/@logical_block_size")
physical_block_size = XMLProperty("./blockio/@physical_block_size")
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)
seclabels = XMLChildProperty(_DiskSeclabel, relative_xpath="./source")
def add_seclabel(self):
obj = _DiskSeclabel(self.conn)
self.add_child(obj)
return obj
#################################
# Validation assistance methods #
#################################
def _set_default_storage_backend(self):
path = None
vol_object = None
parent_pool = None
self._source_volume_err = None
typ = self._get_default_type()
if self.type == VirtualDisk.TYPE_NETWORK:
# Fill in a completed URL for virt-manager UI, path comparison, etc
path = self._build_url_from_network_source()
if typ == VirtualDisk.TYPE_VOLUME:
conn = self.conn
if "weakref" in str(type(conn)):
conn = conn()
try:
parent_pool = conn.storagePoolLookupByName(self.source_pool)
vol_object = parent_pool.storageVolLookupByName(
self.source_volume)
except Exception as e:
self._source_volume_err = str(e)
logging.debug("Error fetching source pool=%s vol=%s",
self.source_pool, self.source_volume, exc_info=True)
if vol_object is None and path is None:
path = self._get_xmlpath()
self._change_backend(path, vol_object, parent_pool)
def set_local_disk_to_clone(self, disk, sparse):
"""
Set a path to manually clone (as in, not through libvirt)
"""
self._storage_backend = diskbackend.CloneStorageCreator(self.conn,
self.path, disk.path, disk.get_size(), sparse)
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, parent_pool):
backend = diskbackend.StorageBackend(self.conn, path,
vol_object, parent_pool)
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.
"""
path = self._get_xmlpath()
self.type = self._get_default_type()
self.driver_name = self._get_default_driver_name()
self.driver_type = self._get_default_driver_type()
# Need to retrigger this if self.type changed
if path:
self._set_xmlpath(path)
def wants_storage_creation(self):
"""
If true, this disk needs storage creation parameters or things
will error.
"""
return (self._storage_backend and
not self._storage_backend.exists())
def validate(self):
if self.path is None:
if self._source_volume_err:
raise RuntimeError(self._source_volume_err)
if not self.can_be_empty():
raise ValueError(_("Device type '%s' requires a path") %
self.device)
return
if (self.type == VirtualDisk.TYPE_DIR and
not self.is_floppy()):
raise ValueError(_("The path '%s' must be a file or a "
"device, not a directory") % self.path)
if not self._storage_backend:
return
if (not self._storage_backend.will_create_storage() and
not self._storage_backend.exists()):
raise ValueError(
_("Must specify storage creation parameters for "
"non-existent path '%s'.") % self.path)
self._storage_backend.validate(self)
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.
"""
if not self._storage_backend.will_create_storage():
return
meter = util.ensure_meter(meter)
vol_object = self._storage_backend.create(meter)
self.storage_was_created = True
if not vol_object:
return
parent_pool = self.get_vol_install().pool
self._change_backend(None, vol_object, parent_pool)
def set_defaults(self, guest):
if self.is_cdrom():
self.read_only = True
if self.is_cdrom() and guest.os.is_s390x():
self.bus = "scsi"
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")
"""
return self._storage_backend.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 for bus '%s' are supported"
% (maxnode, self.bus)))
VirtualDisk.register_type()
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