基于虚拟机的透明计算设备子系统设计及实现*

为解决在现有透明计算系统中磁盘等设备的虚拟化，需要对操作系统进行修改才能在端计算机上运行的问题，提出透明计算系统中一种基于虚拟机技术的设备子系统。以Intel VT硬件级虚拟支持和Xen虚拟化技术为基础, 在全虚拟化的虚拟机上运行用户操作系统: 通过运行在管理域用户空间中设备模型的虚拟磁盘和网络驱动，将用户域访问磁盘和网络的I/O请求跨网络地重定向到服务器进行处理, 从而实现端计算机上多操作系统的远程运行。在VT硬件平台和Xen虚拟机监控器上实现了原型系统，验证了该方法的可行性。

Design and implementation of device sub system of transparent computing system based on machine virtualization

To host an operating system on client devices in a transparent system,the operating system needs to be modified to support device I/O redirection to the server: corresponding virtualized device drivers must be ported to replace original dri-vers.Besides,this method was difficult to be implemented in an operating systems without open interfaces,such as Windows XP.This paper presented a virtualized machine-based device subsystem to solve this problem.By leveraging hardware-supported virtualization of Intel VT and full virtualization approach of Xen,the I/O requested to disk and network devices in the guest domain were redirected to the transparent computing server through presented virtual device drivers integrated into the service domain.As a result,operating systems could run in a transparent client device unmodified.It also implemented a prototype,which verified feasibility of the new method.