OpenStack桌面虚拟化支持USB重定向和声卡

测试OpenStack的桌面虚拟化，默认情况下生成的libvirt的xml是不支持USB重定向和声卡，最快捷的方法就是，Hack下源码，硬加进去：

vim /usr/lib/python2.6/site-packages/nova/virt/libvirt/driver.py

    def to_xml(self, context, instance, network_info, disk_info,

               image_meta=None, rescue=None,

               block_device_info=None, write_to_disk=False):

        # We should get image metadata every time for generating xml

        if image_meta is None:

            (image_service, image_id) = glance.get_remote_image_service(

                                            context, instance['image_ref'])

            image_meta = compute_utils.get_image_metadata(

                                context, image_service, image_id, instance)

        # NOTE(danms): Stringifying a NetworkInfo will take a lock. Do

        # this ahead of time so that we don't acquire it while also

        # holding the logging lock.

        network_info_str = str(network_info)

        LOG.debug(_('Start to_xml '

                    'network_info=%(network_info)s '

                    'disk_info=%(disk_info)s '

                    'image_meta=%(image_meta)s rescue=%(rescue)s'

                    'block_device_info=%(block_device_info)s'),

                  {'network_info': network_info_str, 'disk_info': disk_info,

                   'image_meta': image_meta, 'rescue': rescue,

                   'block_device_info': block_device_info},

                  instance=instance)

        conf = self.get_guest_config(instance, network_info, image_meta,

                                     disk_info, rescue, block_device_info)

        pre_xml = conf.to_xml()

        hack_xml = """

<append>

<controller type='usb' index='0' model='ich9-ehci1'/>

<controller type='usb' index='0' model='ich9-uhci1'>

  <master startport='0'/>

</controller>

<controller type='usb' index='0' model='ich9-uhci2'>

  <master startport='2'/>

</controller>

<controller type='usb' index='0' model='ich9-uhci3'>

  <master startport='4'/>

</controller>

<redirdev bus='usb' type='spicevmc'/>

<redirdev bus='usb' type='spicevmc'/>

<redirdev bus='usb' type='spicevmc'/>

<redirdev bus='usb' type='spicevmc'/>

<sound model='ich6'>

  <alias name='sound0'/>

</sound>

</append>

"""

        tar_obj = ''

        libvit_obj = minidom.parseString(pre_xml)

        hack_obj = minidom.parseString(hack_xml)

        for c_lib_obj in libvit_obj.childNodes[0].childNodes:

            if (isinstance(c_lib_obj, minidom.Element) and c_lib_obj.tagName == 'devices'):

                c_lib_obj.childNodes.extend(hack_obj.childNodes[0].childNodes)

        xml = libvit_obj.toxml()

        if write_to_disk:

            instance_dir = libvirt_utils.get_instance_path(instance)

            xml_path = os.path.join(instance_dir, 'libvirt.xml')

            libvirt_utils.write_to_file(xml_path, xml)

        LOG.debug(_('End to_xml xml=%(xml)s'),

                  {'xml': xml}, instance=instance)

        return xml

简单的说，就是让Nova生成libvirt xml的时候，硬编码进去相关的xml标签

如果还是不行尝试把/usr/lib/python2.7/site-packages/nova/virt/libvirt/文件夹下的driver.pyc和driver.pyo文件删除或改个名，你修改的driver.py就可以生效了