sushy-tools/sushy_tools/emulator/drivers/libvirtdriver.py

590 lines
20 KiB
Python

# Copyright 2018 Red Hat, Inc.
# 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.
from collections import namedtuple
import logging
import uuid
import xml.etree.ElementTree as ET
from sushy_tools.emulator.drivers.base import AbstractDriver
from sushy_tools.emulator.drivers import memoize
from sushy_tools import error
try:
import libvirt
except ImportError:
libvirt = None
is_loaded = bool(libvirt)
logger = logging.getLogger(__name__)
BiosProcessResult = namedtuple('BiosProcessResult',
['tree',
'attributes_written',
'bios_attributes'])
class libvirt_open(object):
def __init__(self, uri, readonly=False):
self._uri = uri
self._readonly = readonly
def __enter__(self):
try:
self._conn = (libvirt.openReadOnly(self._uri)
if self._readonly else
libvirt.open(self._uri))
return self._conn
except libvirt.libvirtError as e:
msg = ('Error when connecting to the libvirt URI "%(uri)s": '
'%(error)s' % {'uri': self._uri, 'error': e})
raise error.FishyError(msg)
def __exit__(self, type, value, traceback):
self._conn.close()
class LibvirtDriver(AbstractDriver):
"""Libvirt driver"""
# XML schema: https://libvirt.org/formatdomain.html#elementsOSBIOS
BOOT_DEVICE_MAP = {
'Pxe': 'network',
'Hdd': 'hd',
'Cd': 'cdrom',
}
BOOT_DEVICE_MAP_REV = {v: k for k, v in BOOT_DEVICE_MAP.items()}
LIBVIRT_URI = 'qemu:///system'
BOOT_MODE_MAP = {
'Legacy': 'rom',
'Uefi': 'pflash'
}
BOOT_MODE_MAP_REV = {v: k for k, v in BOOT_MODE_MAP.items()}
BOOT_LOADER_MAP = {
'Uefi': {
'x86_64': '/usr/share/OVMF/OVMF_CODE.fd',
'aarch64': '/usr/share/AAVMF/AAVMF_CODE.fd'
},
'Legacy': {
'x86_64': None,
'aarch64': None
}
}
DEFAULT_BIOS_ATTRIBUTES = {"BootMode": "Uefi",
"EmbeddedSata": "Raid",
"NicBoot1": "NetworkBoot",
"ProcTurboMode": "Enabled"}
@classmethod
def initialize(cls, config, uri=None):
cls._config = config
cls._uri = uri or cls.LIBVIRT_URI
cls.BOOT_LOADER_MAP = cls._config.get(
'SUSHY_EMULATOR_BOOT_LOADER_MAP', cls.BOOT_LOADER_MAP)
cls.KNOWN_BOOT_LOADERS = set(y for x in cls.BOOT_LOADER_MAP.values()
for y in x.values())
return cls
@memoize.memoize()
def _get_domain(self, identity, readonly=False):
with libvirt_open(self._uri, readonly=readonly) as conn:
try:
uu_identity = uuid.UUID(identity)
return conn.lookupByUUID(uu_identity.bytes)
except (ValueError, libvirt.libvirtError):
try:
domain = conn.lookupByName(identity)
except libvirt.libvirtError as ex:
msg = ('Error finding domain by name/UUID "%(identity)s" '
'at libvirt URI %(uri)s": %(err)s' %
{'identity': identity,
'uri': self._uri, 'err': ex})
logger.debug(msg)
raise error.FishyError(msg)
raise error.AliasAccessError(domain.UUIDString())
@property
def driver(self):
"""Return human-friendly driver information
:returns: driver information as string
"""
return '<libvirt>'
@property
def systems(self):
"""Return available computer systems
:returns: list of UUIDs representing the systems
"""
with libvirt_open(self._uri, readonly=True) as conn:
return [conn.lookupByName(domain).UUIDString()
for domain in conn.listDefinedDomains()]
def uuid(self, identity):
"""Get computer system UUID
The universal unique identifier (UUID) for this system. Can be used
in place of system name if there are duplicates.
:param identity: libvirt domain name or UUID
:returns: computer system UUID
"""
domain = self._get_domain(identity, readonly=True)
return domain.UUIDString()
def name(self, identity):
"""Get computer system name by name
:param identity: libvirt domain name or UUID
:returns: computer system name
"""
domain = self._get_domain(identity, readonly=True)
return domain.name()
def get_power_state(self, identity):
"""Get computer system power state
:param identity: libvirt domain name or ID
:returns: current power state as *On* or *Off* `str` or `None`
if power state can't be determined
"""
domain = self._get_domain(identity, readonly=True)
return 'On' if domain.isActive() else 'Off'
def set_power_state(self, identity, state):
"""Set computer system power state
:param identity: libvirt domain name or ID
:param state: string literal requesting power state transition.
If not specified, current system power state is returned.
Valid values are: *On*, *ForceOn*, *ForceOff*, *GracefulShutdown*,
*GracefulRestart*, *ForceRestart*, *Nmi*.
:raises: `error.FishyError` if power state can't be set
"""
domain = self._get_domain(identity)
try:
if state in ('On', 'ForceOn'):
if not domain.isActive():
domain.create()
elif state == 'ForceOff':
if domain.isActive():
domain.destroy()
elif state == 'GracefulShutdown':
if domain.isActive():
domain.shutdown()
elif state == 'GracefulRestart':
if domain.isActive():
domain.reboot()
elif state == 'ForceRestart':
if domain.isActive():
domain.reset()
elif state == 'Nmi':
if domain.isActive():
domain.injectNMI()
except libvirt.libvirtError as e:
msg = ('Error changing power state at libvirt URI "%(uri)s": '
'%(error)s' % {'uri': self._uri, 'error': e})
raise error.FishyError(msg)
def get_boot_device(self, identity):
"""Get computer system boot device name
:param identity: libvirt domain name or ID
:returns: boot device name as `str` or `None` if device name
can't be determined
"""
domain = self._get_domain(identity, readonly=True)
tree = ET.fromstring(domain.XMLDesc())
boot_element = tree.find('.//boot')
if boot_element is not None:
boot_source_target = (
self.BOOT_DEVICE_MAP_REV.get(boot_element.get('dev'))
)
return boot_source_target
def set_boot_device(self, identity, boot_source):
"""Get/Set computer system boot device name
:param identity: libvirt domain name or ID
:param boot_source: optional string literal requesting boot device
change on the system. If not specified, current boot device is
returned. Valid values are: *Pxe*, *Hdd*, *Cd*.
:raises: `error.FishyError` if boot device can't be set
"""
domain = self._get_domain(identity)
# XML schema: https://libvirt.org/formatdomain.html#elementsOSBIOS
tree = ET.fromstring(domain.XMLDesc())
try:
target = self.BOOT_DEVICE_MAP[boot_source]
except KeyError:
msg = ('Unknown power state requested: '
'%(boot_source)s' % {'boot_source': boot_source})
raise error.FishyError(msg)
for os_element in tree.findall('os'):
# Remove all "boot" elements
for boot_element in os_element.findall('boot'):
os_element.remove(boot_element)
# Add a new boot element with the request boot device
boot_element = ET.SubElement(os_element, 'boot')
boot_element.set('dev', target)
try:
with libvirt_open(self._uri) as conn:
conn.defineXML(ET.tostring(tree).decode('utf-8'))
except libvirt.libvirtError as e:
msg = ('Error changing boot device at libvirt URI "%(uri)s": '
'%(error)s' % {'uri': self._uri, 'error': e})
raise error.FishyError(msg)
def get_boot_mode(self, identity):
"""Get computer system boot mode.
:returns: either *Uefi* or *Legacy* as `str` or `None` if
current boot mode can't be determined
"""
domain = self._get_domain(identity, readonly=True)
# XML schema: https://libvirt.org/formatdomain.html#elementsOSBIOS
tree = ET.fromstring(domain.XMLDesc())
loader_element = tree.find('.//loader')
if loader_element is not None:
boot_mode = (
self.BOOT_MODE_MAP_REV.get(loader_element.get('type'))
)
return boot_mode
def set_boot_mode(self, identity, boot_mode):
"""Set computer system boot mode.
:param boot_mode: optional string literal requesting boot mode
change on the system. If not specified, current boot mode is
returned. Valid values are: *Uefi*, *Legacy*.
:raises: `error.FishyError` if boot mode can't be set
"""
domain = self._get_domain(identity, readonly=True)
# XML schema: https://libvirt.org/formatdomain.html#elementsOSBIOS
tree = ET.fromstring(domain.XMLDesc())
try:
loader_type = self.BOOT_MODE_MAP[boot_mode]
except KeyError:
msg = ('Unknown boot mode requested: '
'%(boot_mode)s' % {'boot_mode': boot_mode})
raise error.FishyError(msg)
loaders = []
for os_element in tree.findall('os'):
type_element = os_element.find('type')
if type_element is None:
os_arch = None
else:
os_arch = type_element.get('arch')
try:
loader_path = self.BOOT_DEVICE_MAP[boot_mode][os_arch]
except KeyError:
logger.warning('Boot loader is not configured for '
'boot mode %s and OS architecture %s. '
'Assuming no specific boot loader.',
boot_mode, os_arch)
loader_path = ''
# NOTE(etingof): here we collect all tree nodes to be
# updated, but do not update them yet. The reason is to
# make sure that previously configured boot loaders are
# all present in our configuration, so we won't lose it
# when setting ours.
for loader_element in os_element.findall('loader'):
if loader_element.text not in self.KNOWN_BOOT_LOADERS:
msg = ('Unknown boot loader path "%(path)s" in domain '
'"%(identity)s" configuration encountered while '
'setting boot mode "%(mode)s", system architecture '
'"%(arch)s". Consider adding this loader path to '
'emulator config.' % {'identity': identity,
'mode': boot_mode,
'arch': os_arch,
'path': loader_element.text})
raise error.FishyError(msg)
loaders.append((loader_element, loader_path))
if not loaders:
msg = ('Can\'t set boot mode because no "os" elements are present '
'in domain "%(identity)s" or not a single "os" element has '
'"loader" configured.' % {'identity': identity})
raise error.FishyError(msg)
for loader_element, loader_path in loaders:
loader_element.set('type', loader_type)
loader_element.text = loader_path
with libvirt_open(self._uri) as conn:
try:
conn.defineXML(ET.tostring(tree).decode('utf-8'))
except libvirt.libvirtError as e:
msg = ('Error changing boot mode at libvirt URI '
'"%(uri)s": %(error)s' % {'uri': self._uri,
'error': e})
raise error.FishyError(msg)
def get_total_memory(self, identity):
"""Get computer system total memory
:param identity: libvirt domain name or ID
:returns: available RAM in GiB as `int` or `None` if total memory
count can't be determined
"""
domain = self._get_domain(identity, readonly=True)
return int(domain.maxMemory() / 1024 / 1024)
def get_total_cpus(self, identity):
"""Get computer system total count of available CPUs
:param identity: libvirt domain name or ID
:returns: available CPU count as `int` or `None` if CPU count
can't be determined
"""
domain = self._get_domain(identity, readonly=True)
tree = ET.fromstring(domain.XMLDesc())
total_cpus = 0
if domain.isActive():
total_cpus = domain.maxVcpus()
# If we can't get it from maxVcpus() try to find it by
# inspecting the domain XML
if total_cpus <= 0:
vcpu_element = tree.find('.//vcpu')
if vcpu_element is not None:
total_cpus = int(vcpu_element.text)
return total_cpus or None
def _process_bios_attributes(self,
domain_xml,
bios_attributes=DEFAULT_BIOS_ATTRIBUTES,
update_existing_attributes=False):
"""Process Libvirt domain XML for BIOS attributes
This method supports adding default BIOS attributes,
retrieving existing BIOS attributes and
updating existing BIOS attributes.
This method is introduced to make XML testable otherwise have to
compare XML strings to test if XML saved to libvirt is as expected.
Sample of custom XML:
<domain type="kvm">
[...]
<metadata xmlns:sushy="http://openstack.org/xmlns/libvirt/sushy">
<sushy:bios>
<sushy:attributes>
<sushy:attribute name="ProcTurboMode" value="Enabled"/>
<sushy:attribute name="BootMode" value="Uefi"/>
<sushy:attribute name="NicBoot1" value="NetworkBoot"/>
<sushy:attribute name="EmbeddedSata" value="Raid"/>
</sushy:attributes>
</sushy:bios>
</metadata>
[...]
:param domain_xml: Libvirt domain XML to process
:param bios_attributes: BIOS attributes for updates or default
values if not specified
:param update_existing_attributes: Update existing BIOS attributes
:returns: namedtuple of tree: processed XML element tree,
attributes_written: if changes were made to XML,
bios_attributes: dict of BIOS attributes
"""
namespace = 'http://openstack.org/xmlns/libvirt/sushy'
ET.register_namespace('sushy', namespace)
ns = {'sushy': namespace}
tree = ET.fromstring(domain_xml)
metadata = tree.find('metadata')
if metadata is None:
metadata = ET.SubElement(tree, 'metadata')
bios = metadata.find('sushy:bios', ns)
attributes_written = False
if bios is not None and update_existing_attributes:
metadata.remove(bios)
bios = None
if bios is None:
bios = ET.SubElement(metadata, '{%s}bios' % (namespace))
attributes = ET.SubElement(bios, '{%s}attributes' % (namespace))
for key, value in sorted(bios_attributes.items()):
ET.SubElement(attributes,
'{%s}attribute' % (namespace),
name=key,
value=value)
attributes_written = True
bios_attributes = {atr.attrib['name']: atr.attrib['value']
for atr in tree.find('.//sushy:attributes', ns)}
return BiosProcessResult(tree, attributes_written, bios_attributes)
def _process_bios(self, identity,
bios_attributes=DEFAULT_BIOS_ATTRIBUTES,
update_existing_attributes=False):
"""Process Libvirt domain XML for BIOS attributes and update it if necessary
:param identity: libvirt domain name or ID
:param bios_attributes: Full list of BIOS attributes to use if
they are missing or update necessary
:param update_existing_attributes: Update existing BIOS attributes
:returns: New or existing dict of BIOS attributes
:raises: `error.FishyError` if BIOS attributes cannot be saved
"""
domain = self._get_domain(identity)
result = self._process_bios_attributes(domain.XMLDesc(),
bios_attributes,
update_existing_attributes)
if result.attributes_written:
try:
with libvirt_open(self._uri) as conn:
conn.defineXML(ET.tostring(result.tree).decode('utf-8'))
except libvirt.libvirtError as e:
msg = ('Error updating BIOS attributes'
' at libvirt URI "%(uri)s": '
'%(error)s' % {'uri': self._uri, 'error': e})
raise error.FishyError(msg)
return result.bios_attributes
def get_bios(self, identity):
"""Get BIOS section
If there are no BIOS attributes, domain is updated with default values.
:param identity: libvirt domain name or ID
:returns: dict of BIOS attributes
"""
return self._process_bios(identity)
def set_bios(self, identity, attributes):
"""Update BIOS attributes
These values do not have any effect on VM. This is a workaround
because there is no libvirt API to manage BIOS settings.
By storing fake BIOS attributes they are attached to VM and are
persisted through VM lifecycle.
Updates to attributes are immediate unlike in real BIOS that
would require system reboot.
:param identity: libvirt domain name or ID
:param attributes: dict of BIOS attributes to update. Can pass only
attributes that need update, not all
"""
bios_attributes = self.get_bios(identity)
bios_attributes.update(attributes)
self._process_bios(identity, bios_attributes,
update_existing_attributes=True)
def reset_bios(self, identity):
"""Reset BIOS attributes to default
:param identity: libvirt domain name or ID
"""
self._process_bios(identity, self.DEFAULT_BIOS_ATTRIBUTES,
update_existing_attributes=True)
def get_nics(self, identity):
"""Get list of network interfaces and their MAC addresses
Use MAC address as network interface's id
:param identity: libvirt domain name or ID
:returns: list of network interfaces dict with their attributes
"""
domain = self._get_domain(identity, readonly=True)
tree = ET.fromstring(domain.XMLDesc())
return [{'id': iface.get('address'), 'mac': iface.get('address')}
for iface in tree.findall(
".//devices/interface[@type='network']/mac")]