openstack关于libvirt相关代码的分析（一）
来源：互联网 发布：淘宝网页html模板代码 编辑：程序博客网 时间：2024/06/03 14:53
这段时间研究openstack+xen可惜资料太少，决定看一下源代码得了。
如果看过一篇关于启动Openstack中启动一个虚拟机的过程的文章的话，就一定知道有一个叫做Spawn instance的过程。
我使用的代码是nova-2012.2的版本。
下面我们看一下nova/virt/libvirt/connection.py文件。
"""A connection to a hypervisor through libvirt.Supports KVM, LXC, QEMU, UML, and XEN.**Related Flags**:libvirt_type: Libvirt domain type. Can be kvm, qemu, uml, xen (default: kvm).:libvirt_uri: Override for the default libvirt URI (depends on libvirt_type).:libvirt_disk_prefix: Override the default disk prefix for the devices attached to a server.:rescue_image_id: Rescue ami image (None = original image).:rescue_kernel_id: Rescue aki image (None = original image).:rescue_ramdisk_id: Rescue ari image (None = original image).:injected_network_template: Template file for injected network:allow_same_net_traffic: Whether to allow in project network traffic
我们需要创建以个libvirt xml去新建一个实例。这将会涉及到其中的to_xml函数。
def to_xml(self, instance, network_info, image_meta=None, rescue=False, block_device_info=None): LOG.debug(_('Starting toXML method'), instance=instance) conf = self.get_guest_config(instance, network_info, image_meta, rescue, block_device_info) xml = conf.to_xml() LOG.debug(_('Finished toXML method'), instance=instance) return xml可以看到，它调用了一个叫get_guest_config的函数
def get_guest_config(self, instance, network_info, image_meta, rescue, block_device_info=None): block_device_mapping = driver.block_device_info_get_mapping( block_device_info) devs = [] # FIXME(vish): stick this in db inst_type_id = instance['instance_type_id'] inst_type = instance_types.get_instance_type(inst_type_id) guest = config.LibvirtConfigGuest() guest.virt_type = FLAGS.libvirt_type guest.name = instance['name'] guest.uuid = instance['uuid'] guest.memory = inst_type['memory_mb'] * 1024 guest.vcpus = inst_type['vcpus'] root_device_name = driver.block_device_info_get_root(block_device_info) if root_device_name: root_device = block_device.strip_dev(root_device_name) else: # NOTE(yamahata): # for nova.api.ec2.cloud.CloudController.get_metadata() root_device = self.default_root_device db.instance_update( nova_context.get_admin_context(), instance['id'], {'root_device_name': '/dev/' + self.default_root_device}) if FLAGS.libvirt_type == "lxc": guest.os_type = "exe" guest.os_init_path = "/sbin/init" guest.os_cmdline = "console=ttyS0" elif FLAGS.libvirt_type == "uml": guest.os_type = "uml" guest.os_kernel = "/usr/bin/linux" guest.os_root = root_device_name or "/dev/ubda" else: if FLAGS.libvirt_type == "xen": guest.os_type = "linux" guest.os_root = root_device_name or "/dev/xvda" else: guest.os_type = "hvm" if rescue: guest.os_kernel = os.path.join(FLAGS.instances_path, instance['name'], "kernel.rescue") guest.os_initrd = os.path.join(FLAGS.instances_path, instance['name'], "ramdisk.rescue") elif instance['kernel_id']: guest.os_kernel = os.path.join(FLAGS.instances_path, instance['name'], "kernel") if FLAGS.libvirt_type == "xen": guest.os_cmdline = "ro" else: guest.os_cmdline = "root=%s console=ttyS0" % ( root_device_name or "/dev/vda",) if instance['ramdisk_id']: guest.os_initrd = os.path.join(FLAGS.instances_path, instance['name'], "ramdisk") else: guest.os_boot_dev = "hd" if FLAGS.libvirt_type != "lxc" and FLAGS.libvirt_type != "uml": guest.acpi = True if FLAGS.libvirt_type == "lxc": fs = config.LibvirtConfigGuestFilesys() fs.type = "mount" fs.source_dir = os.path.join(FLAGS.instances_path, instance['name'], "rootfs") guest.add_device(fs) else: if FLAGS.use_cow_images: driver_type = 'qcow2' else: driver_type = 'raw' if image_meta and image_meta.get('disk_format') == 'iso': root_device_type = 'cdrom' else: root_device_type = 'disk' if FLAGS.libvirt_type == "uml": ephemeral_disk_bus = "uml" elif FLAGS.libvirt_type == "xen": ephemeral_disk_bus = "xen" else: ephemeral_disk_bus = "virtio" if rescue: diskrescue = config.LibvirtConfigGuestDisk() diskrescue.source_type = "file" diskrescue.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk.rescue") diskrescue.driver_format = driver_type diskrescue.driver_cache = self.disk_cachemode diskrescue.target_dev = self.default_root_device diskrescue.target_bus = ephemeral_disk_bus guest.add_device(diskrescue) diskos = config.LibvirtConfigGuestDisk() diskos.source_type = "file" diskos.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk") diskos.driver_format = driver_type diskos.driver_cache = self.disk_cachemode diskos.target_dev = self.default_second_device diskos.target_bus = ephemeral_disk_bus guest.add_device(diskos) else: ebs_root = self._volume_in_mapping(self.default_root_device, block_device_info) if not ebs_root: diskos = config.LibvirtConfigGuestDisk() diskos.source_type = "file" diskos.source_device = root_device_type diskos.driver_format = driver_type diskos.driver_cache = self.disk_cachemode diskos.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk") diskos.target_dev = root_device if root_device_type == "cdrom": diskos.target_bus = "ide" else: diskos.target_bus = "virtio" guest.add_device(diskos) ephemeral_device = None if not (self._volume_in_mapping(self.default_second_device, block_device_info) or 0 in [eph['num'] for eph in driver.block_device_info_get_ephemerals( block_device_info)]): if instance['ephemeral_gb'] > 0: ephemeral_device = self.default_second_device if ephemeral_device is not None: disklocal = config.LibvirtConfigGuestDisk() disklocal.source_type = "file" disklocal.source_device = root_device_type disklocal.driver_format = driver_type disklocal.driver_cache = self.disk_cachemode disklocal.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk.local") disklocal.target_dev = ephemeral_device disklocal.target_bus = ephemeral_disk_bus guest.add_device(disklocal) if ephemeral_device is not None: swap_device = self.default_third_device db.instance_update( nova_context.get_admin_context(), instance['id'], {'default_ephemeral_device': '/dev/' + self.default_second_device}) else: swap_device = self.default_second_device for eph in driver.block_device_info_get_ephemerals( block_device_info): diskeph = config.LibvirtConfigGuestDisk() diskeph.source_type = "block" diskeph.source_device = root_device_type diskeph.driver_format = driver_type diskeph.driver_cache = self.disk_cachemode diskeph.source_path = os.path.join(FLAGS.instances_path, instance['name'], _get_eph_disk(eph)) diskeph.target_dev = block_device.strip_dev( eph['device_name']) diskeph.target_bus = ephemeral_disk_bus guest.add_device(diskeph) swap = driver.block_device_info_get_swap(block_device_info) if driver.swap_is_usable(swap): diskswap = config.LibvirtConfigGuestDisk() diskswap.disk_type = "file" diskswap.driver_format = driver_type diskswap.driver_cache = self.disk_cachemode diskswap.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk.swap") diskswap.target_dev = block_device.strip_dev( swap['device_name']) diskswap.target_bus = ephemeral_disk_bus guest.add_device(diskswap) elif (inst_type['swap'] > 0 and not self._volume_in_mapping(swap_device, block_device_info)): diskswap = config.LibvirtConfigGuestDisk() diskswap.disk_type = "file" diskswap.driver_format = driver_type diskswap.driver_cache = self.disk_cachemode diskswap.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk.swap") diskswap.target_dev = swap_device diskswap.target_bus = ephemeral_disk_bus guest.add_device(diskswap) db.instance_update( nova_context.get_admin_context(), instance['id'], {'default_swap_device': '/dev/' + swap_device}) for vol in block_device_mapping: connection_info = vol['connection_info'] mountpoint = vol['mount_device'] cfg = self.volume_driver_method('connect_volume', connection_info, mountpoint) guest.add_device(cfg) if self._has_config_drive(instance): diskconfig = config.LibvirtConfigGuestDisk() diskconfig.source_type = "file" diskconfig.driver_format = "raw" diskconfig.driver_cache = self.disk_cachemode diskconfig.source_path = os.path.join(FLAGS.instances_path, instance['name'], "disk.config") diskconfig.target_dev = self.default_last_device diskconfig.target_bus = ephemeral_disk_bus guest.add_device(diskconfig) for (network, mapping) in network_info: cfg = self.vif_driver.plug(instance, network, mapping) guest.add_device(cfg) if FLAGS.libvirt_type == "qemu" or FLAGS.libvirt_type == "kvm": # The QEMU 'pty' driver throws away any data if no # client app is connected. Thus we can't get away # with a single type=pty console. Instead we have # to configure two separate consoles. consolelog = config.LibvirtConfigGuestSerial() consolelog.type = "file" consolelog.source_path = os.path.join(FLAGS.instances_path, instance['name'], "console.log") guest.add_device(consolelog) consolepty = config.LibvirtConfigGuestSerial() consolepty.type = "pty" guest.add_device(consolepty) else: consolepty = config.LibvirtConfigGuestConsole() consolepty.type = "pty" guest.add_device(consolepty) if FLAGS.vnc_enabled and FLAGS.libvirt_type not in ('lxc', 'uml'): if FLAGS.use_usb_tablet: tablet = config.LibvirtConfigGuestInput() tablet.type = "tablet" tablet.bus = "usb" guest.add_device(tablet) graphics = config.LibvirtConfigGuestGraphics() graphics.type = "vnc" graphics.keymap = FLAGS.vnc_keymap graphics.listen = FLAGS.vncserver_listen guest.add_device(graphics) return guest
- openstack关于libvirt相关代码的分析（一）
- Openstack J版本 NUMA特性相关分析（一）
- openstack--nova的运行机制分析（一）
- libvirt之virsh代码分析
- OpenStack基于Libvirt的虚拟化平台调度实现----Nova虚拟机动态迁移源码分析
- openstack nova 源码分析5-1 -nova/virt/libvirt目录下的connection.py
- openstack nova 源码分析5-2 -nova/virt/libvirt目录下的connection.py
- openstack nova 源码分析5-3 -nova/virt/libvirt目录下的connection.py
- openstack nova 源码分析5-4 -nova/virt/libvirt目录下的connection.py
- OpenStack基于Libvirt的虚拟化平台调度实现----Nova虚拟机动态迁移源码分析
- OpenStack基于Libvirt的虚拟化平台调度实现----Nova虚拟机动态迁移源码分析
- OpenStack Eventlet分析（一）
- libvirt 快照 （一）
- OpenStack文件注入相关分析（1）
- OpenStack文件注入相关分析（2）
- OpenStack文件注入相关分析（转载）
- OpenStack performance相关分析
- OpenStack中网络模块（Neutron）的代码分析
- hdu 1011 tree dp+背包 有trick
- Android客户端解密与C#服务端加密实现方法
- vc 2005 2008 2010 安装ie8后不能添加控件变量解决方法
- Personality Characteristics of Great Designers
- 值的收藏的js效果： 滚动条下拉时，右下角显示弹出框
- openstack关于libvirt相关代码的分析（一）
- zoj2970
- 不同Bean创建方式以及对应配置
- 新手.......
- 新型锂电池 充电速度比普通电池快120倍！
- zoj2987
- linux驱动移植笔记
- 软件与机械制造
- hdu 4046 树状数组
