virt-manager/virtinst/capabilities.py

724 lines
22 KiB
Python

#
# Some code for parsing libvirt's capabilities XML
#
# Copyright 2007, 2012-2013 Red Hat, Inc.
# Mark McLoughlin <markmc@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 re
from virtinst import util
# Whether a guest can be created with a certain feature on resp. off
FEATURE_ON = 0x01
FEATURE_OFF = 0x02
def xpathString(node, path, default=None):
result = node.xpathEval("string(%s)" % path)
if len(result) == 0:
result = default
return result
class CPUValuesModel(object):
"""
Single <model> definition from cpu_map
"""
def __init__(self, node):
self.model = node.prop("name")
self.features = []
self.parent = None
self.vendor = None
self._parseXML(node)
def _parseXML(self, node):
child = node.children
while child:
if child.name == "model":
self.parent = child.prop("name")
if child.name == "vendor":
self.vendor = child.prop("name")
if child.name == "feature":
self.features.append(child.prop("name"))
child = child.next
self.features.sort()
def inheritParent(self, parentcpu):
self.vendor = parentcpu.vendor or self.vendor
self.features += parentcpu.features
self.features.sort()
class CPUValuesArch(object):
"""
Single <arch> instance of valid CPUs
"""
def __init__(self, arch, node=None):
self.arch = arch
self.vendors = []
self.cpus = []
self.features = []
if node:
self._parseXML(node)
def _parseXML(self, node):
child = node.children
while child:
if child.name == "vendor":
self.vendors.append(child.prop("name"))
if child.name == "feature":
self.features.append(child.prop("name"))
if child.name == "model":
newcpu = CPUValuesModel(child)
if newcpu.parent:
for chkcpu in self.cpus:
if chkcpu.model == newcpu.parent:
newcpu.inheritParent(chkcpu)
self.cpus.append(newcpu)
child = child.next
self.vendors.sort()
self.features.sort()
def get_cpu(self, model):
for c in self.cpus:
if c.model == model:
return c
raise ValueError(_("Unknown CPU model '%s'") % model)
class CPUValues(object):
"""
Lists valid values for domain <cpu> parameters, parsed from libvirt's
local cpu_map.xml
"""
def __init__(self, cpu_filename=None):
self.archmap = {}
if not cpu_filename:
cpu_filename = "/usr/share/libvirt/cpu_map.xml"
xml = file(cpu_filename).read()
util.parse_node_helper(xml, "cpus",
self._parseXML,
RuntimeError)
def _parseXML(self, node):
child = node.children
while child:
if child.name == "arch":
arch = child.prop("name")
self.archmap[arch] = CPUValuesArch(arch, child)
child = child.next
def get_arch(self, arch):
if re.match(r'i[4-9]86', arch):
arch = "x86"
elif arch == "x86_64":
arch = "x86"
cpumap = self.archmap.get(arch)
if not cpumap:
cpumap = CPUValuesArch(arch)
self.archmap[arch] = cpumap
return cpumap
class Features(object):
"""Represent a set of features. For each feature, store a bit mask of
FEATURE_ON and FEATURE_OFF to indicate whether the feature can
be turned on or off. For features for which toggling doesn't make sense
(e.g., 'vmx') store FEATURE_ON when the feature is present."""
def __init__(self, node=None):
self.features = {}
if node is not None:
self.parseXML(node)
def __getitem__(self, feature):
if feature in self.features:
return self.features[feature]
return 0
def names(self):
return self.features.keys()
def parseXML(self, node):
d = self.features
feature_list = []
if node.name == "features":
node_list = node.xpathEval("*")
for n in node_list:
feature_list.append(n.name)
else:
# New style features
node_list = node.xpathEval("feature/@name")
for n in node_list:
feature_list.append(n.content)
for feature in feature_list:
if feature not in d:
d[feature] = 0
self._extractFeature(feature, d, n)
def _extractFeature(self, feature, d, node):
"""Extract the value of FEATURE from NODE and set DICT[FEATURE] to
its value. Abstract method, must be overridden"""
raise NotImplementedError("Abstract base class")
class CapabilityFeatures(Features):
def __init__(self, node=None):
Features.__init__(self, node)
def _extractFeature(self, feature, d, n):
default = xpathString(n, "@default")
toggle = xpathString(n, "@toggle")
if default is not None:
# Format for guest features
if default == "on":
d[feature] = FEATURE_ON
elif default == "off":
d[feature] = FEATURE_OFF
else:
raise RuntimeError("Feature %s: value of default must "
"be 'on' or 'off', but is '%s'" %
(feature, default))
if toggle == "yes":
d[feature] |= d[feature] ^ (FEATURE_ON | FEATURE_OFF)
else:
# Format for old HOST features, on OLD old guest features
# back compat is just <$featurename>, like <svm/>
if feature == "nonpae":
d["pae"] |= FEATURE_OFF
else:
d[feature] |= FEATURE_ON
class CPU(object):
def __init__(self, node=None):
# e.g. "i686" or "x86_64"
self.arch = None
self.model = None
self.vendor = None
self.sockets = 1
self.cores = 1
self.threads = 1
self.features = CapabilityFeatures()
if not node is None:
self.parseXML(node)
def parseXML(self, node):
newstyle_features = False
child = node.children
while child:
# Do a first pass to try and detect new style features
if child.name == "feature":
newstyle_features = True
break
child = child.next
if newstyle_features:
self.features = CapabilityFeatures(node)
child = node.children
while child:
if child.name == "arch":
self.arch = child.content
elif child.name == "model":
self.model = child.content
elif child.name == "vendor":
self.vendor = child.content
elif child.name == "topology":
self.sockets = xpathString(child, "@sockets") or 1
self.cores = xpathString(child, "@cores") or 1
self.threads = xpathString(child, "@threads") or 1
elif child.name == "features" and not newstyle_features:
self.features = CapabilityFeatures(child)
child = child.next
class Host(object):
def __init__(self, node=None):
self.cpu = CPU()
self.topology = None
self.secmodels = []
if not node is None:
self.parseXML(node)
def get_secmodel(self):
return self.secmodels and self.secmodels[0] or None
secmodel = property(get_secmodel)
def parseXML(self, node):
child = node.children
while child:
if child.name == "topology":
self.topology = Topology(child)
if child.name == "secmodel":
self.secmodels.append(SecurityModel(child))
if child.name == "cpu":
self.cpu = CPU(child)
child = child.next
class Guest(object):
def __init__(self, node=None):
# e.g. "xen" or "hvm"
self.os_type = None
# e.g. "i686" or "x86_64"
self.arch = None
self.domains = []
self.features = CapabilityFeatures()
if not node is None:
self.parseXML(node)
def parseXML(self, node):
child = node.children
while child:
if child.name == "os_type":
self.os_type = child.content
elif child.name == "features":
self.features = CapabilityFeatures(child)
elif child.name == "arch":
self.arch = child.prop("name")
machines = []
emulator = None
loader = None
n = child.children
while n:
if n.name == "machine":
machines.append(n.content)
canon = n.prop("canonical")
if canon:
machines.append(canon)
elif n.name == "emulator":
emulator = n.content
elif n.name == "loader":
loader = n.content
n = n.next
n = child.children
while n:
if n.name == "domain":
self.domains.append(Domain(n.prop("type"),
emulator, loader, machines, n))
n = n.next
child = child.next
def _favoredDomain(self, accelerated, domains):
"""
Return the recommended domain for use if the user does not explicitly
request one.
"""
if accelerated is None:
# Picking last in list so we favour KVM/KQEMU over QEMU
return domains[-1]
priority = ["kvm", "xen", "kqemu", "qemu"]
if not accelerated:
priority.reverse()
for t in priority:
for d in domains:
if d.hypervisor_type == t:
return d
# Fallback, just return last item in list
return domains[-1]
def bestDomainType(self, accelerated=None, dtype=None, machine=None):
domains = []
for d in self.domains:
if dtype and d.hypervisor_type != dtype.lower():
continue
if machine and machine not in d.machines:
continue
domains.append(d)
if len(domains) == 0:
domainerr = ""
machineerr = ""
if dtype:
domainerr = _(", domain type '%s'") % dtype
if machine:
machineerr = _(", machine type '%s'") % machine
error = (_("No domains available for virt type '%(type)s', "
"arch '%(arch)s'") %
{'type': self.os_type, 'arch': self.arch})
error += domainerr
error += machineerr
raise RuntimeError(error)
return self._favoredDomain(accelerated, domains)
class Domain(object):
def __init__(self, hypervisor_type,
emulator=None, loader=None,
machines=None, node=None):
self.hypervisor_type = hypervisor_type
self.emulator = emulator
self.loader = loader
self.machines = machines
if node is not None:
self.parseXML(node)
def parseXML(self, node):
child = node.children
machines = []
while child:
if child.name == "emulator":
self.emulator = child.content
elif child.name == "machine":
machines.append(child.content)
canon = child.prop("canonical")
if canon:
machines.append(canon)
machines.append(child.content)
child = child.next
if len(machines) > 0:
self.machines = machines
def is_accelerated(self):
return self.hypervisor_type in ["kvm", "kqemu"]
class Topology(object):
def __init__(self, node=None):
self.cells = []
if not node is None:
self.parseXML(node)
def parseXML(self, node):
child = node.children
if child.name == "cells":
for cell in child.children:
if cell.name == "cell":
self.cells.append(TopologyCell(cell))
class TopologyCell(object):
def __init__(self, node=None):
self.id = None
self.cpus = []
if not node is None:
self.parseXML(node)
def parseXML(self, node):
self.id = int(node.prop("id"))
for child in node.children:
if child.name == "cpus":
for cpu in child.children:
if cpu.name == "cpu":
self.cpus.append(TopologyCPU(cpu))
class TopologyCPU(object):
def __init__(self, node=None):
self.id = None
if not node is None:
self.parseXML(node)
def parseXML(self, node):
self.id = int(node.prop("id"))
class SecurityModel(object):
def __init__(self, node=None):
self.model = None
self.doi = None
self.baselabels = {}
if not node is None:
self.parseXML(node)
def parseXML(self, node):
for child in node.children or []:
if child.name == "model":
self.model = child.content
elif child.name == "doi":
self.doi = child.content
elif child.name == "baselabel":
typ = child.prop("type")
self.baselabels[typ] = child.content
class Capabilities(object):
def __init__(self, xml):
self.host = None
self.guests = []
self.xml = xml
self._topology = None
self._cpu_values = None
util.parse_node_helper(self.xml, "capabilities",
self.parseXML,
RuntimeError)
def _is_xen(self):
for g in self.guests:
if g.os_type != "xen":
continue
for d in g.domains:
if d.hypervisor_type == "xen":
return True
return False
def no_install_options(self):
"""
Return True if there are no install options available
"""
for g in self.guests:
if len(g.domains) > 0:
return False
return True
def hw_virt_supported(self):
"""
Return True if the machine supports hardware virtualization.
For some cases (like qemu caps pre libvirt 0.7.4) this info isn't
sufficiently provided, so we will return True in cases that we
aren't sure.
"""
has_hvm_guests = False
for g in self.guests:
if g.os_type == "hvm":
has_hvm_guests = True
break
# Obvious case of feature being specified
if (self.host.cpu.features["vmx"] == FEATURE_ON or
self.host.cpu.features["svm"] == FEATURE_ON):
return True
# Xen seems to block the vmx/svm feature bits from cpuinfo?
# so make sure no hvm guests are listed
if self._is_xen() and has_hvm_guests:
return True
# If there is other features, but no virt bit, then HW virt
# isn't supported
if len(self.host.cpu.features.names()):
return False
# Xen caps have always shown this info, so if we didn't find any
# features, the host really doesn't have the nec support
if self._is_xen():
return False
# Otherwise, we can't be sure, because there was a period for along
# time that qemu caps gave no indication one way or the other.
return True
def is_kvm_available(self):
"""
Return True if kvm guests can be installed
"""
for g in self.guests:
if g.os_type != "hvm":
continue
for d in g.domains:
if d.hypervisor_type == "kvm":
return True
return False
def is_xenner_available(self):
"""
Return True if xenner install option is available
"""
for g in self.guests:
if g.os_type != "xen":
continue
for d in g.domains:
if d.hypervisor_type == "kvm":
return True
return False
def is_bios_virt_disabled(self):
"""
Try to determine if fullvirt may be disabled in the bios.
Check is basically:
- We support HW virt
- We appear to be xen
- There are no HVM install options
We don't do this check for KVM, since no KVM options may mean
KVM isn't installed or the module isn't loaded (and loading the
module will give an appropriate error
"""
if not self.hw_virt_supported():
return False
if not self._is_xen():
return False
for g in self.guests:
if g.os_type == "hvm":
return False
return True
def support_pae(self):
for g in self.guests:
if "pae" in g.features.names():
return True
return False
def guestForOSType(self, typ=None, arch=None):
if self.host is None:
return None
if arch is None:
archs = [self.host.cpu.arch, None]
else:
archs = [arch]
for a in archs:
for g in self.guests:
if (typ is None or g.os_type == typ) and \
(a is None or g.arch == a):
return g
def parseXML(self, node):
child = node.children
while child:
if child.name == "host":
self.host = Host(child)
elif child.name == "guest":
self.guests.append(Guest(child))
child = child.next
def get_cpu_values(self, arch):
if not self._cpu_values:
self._cpu_values = CPUValues()
return self._cpu_values.get_arch(arch)
def guest_lookup(self, os_type=None, arch=None, typ=None,
accelerated=False, machine=None):
"""
Simple virtualization availability lookup
Convenience function for looking up 'Guest' and 'Domain' capabilities
objects for the desired virt type. If type, arch, or os_type are none,
we return the default virt type associated with those values. These are
typically:
- os_type : hvm, then xen
- typ : kvm over plain qemu
- arch : host arch over all others
Otherwise the default will be the first listed in the capabilities xml.
This function throws C{ValueError}s if any of the requested values are
not found.
@param typ: Virtualization type ('hvm', 'xen', ...)
@type typ: C{str}
@param arch: Guest architecture ('x86_64', 'i686' ...)
@type arch: C{str}
@param os_type: Hypervisor name ('qemu', 'kvm', 'xen', ...)
@type os_type: C{str}
@param accelerated: Whether to look for accelerated domain if none is
specifically requested
@type accelerated: C{bool}
@param machine: Optional machine type to emulate
@type machine: C{str}
@returns: A (Capabilities Guest, Capabilities Domain) tuple
"""
guest = self.guestForOSType(os_type, arch)
if not guest:
archstr = _("for arch '%s'") % arch
if not arch:
archstr = ""
osstr = _("virtualization type '%s'") % os_type
if not os_type:
osstr = _("any virtualization options")
raise ValueError(_("Host does not support %(virttype)s %(arch)s") %
{'virttype' : osstr, 'arch' : archstr})
domain = guest.bestDomainType(accelerated=accelerated,
dtype=typ,
machine=machine)
if domain is None:
machinestr = "with machine '%s'" % machine
if not machine:
machinestr = ""
raise ValueError(_("Host does not support domain type %(domain)s"
"%(machine)s for virtualization type "
"'%(virttype)s' arch '%(arch)s'") %
{'domain': typ, 'virttype': guest.os_type,
'arch': guest.arch, 'machine': machinestr})
return (guest, domain)
def build_virtinst_guest(self, conn, guest, domain):
from virtinst import Guest as VGuest
gobj = VGuest(conn)
gobj.type = domain.hypervisor_type
gobj.os.os_type = guest.os_type
gobj.os.arch = guest.arch
gobj.os.loader = domain.loader
gobj.emulator = domain.emulator
return gobj