Realization Of The Vmx Virtual Machine Device Model Design And Virtual Card

With the development of network and the growing need for software compatibility, the research of virtual machine has entered into a glorious time. Meanwhile, with the rapid enhancement of the market for x86 server, the virtual machine for x86 attracts more interests. However, there exits virtualization hole in Intel x86 architecture for historical reason. According to different VMM abstract virtual machine architecture, or according to whether the guest OS need to be modified, virtualization technology could be divided into two kinds: para-virtualization and full-virtualization, therefore, there are two kinds of major virtual machine on x86 platform: VMWare which use full-virtualization and Xen which use para-virtualization. VMWare could be operated on several OS without modifying, but the performance regression is great. Xen requires OS code relating with platform to be modified, and gains excellent performance by co-working with VMM, but it could not be used with Windows OS whose code is not available.The driving power of market asks for VT-x, a processor level support for virtual machine of Intel. VT-x greatly improves the flexibility of VMM, and gives full consideration for how to limit the cost of virtual machine. Taking advantage of Xen's good performance, which is open source, Intel VMM team adds support for VT-x on basis of it, and comes about VMX virtual machine model, which aims at giving a method for high performance of full-virtualization and overcomes the disadvantages of VMWare and Xen. Right now the support for VT-x has been part of Xen 3.0.In order to support VT-x in Xen, we need to make some modification and add some extensions on basis of Xen, among which emulating PC platform device model is one of major parts. I take great pleasure to join in the project, and focus on research and realize the device model. As a software model which emulates all the hardware level programming interface, which make an unmodified device driver could use these interfaces do I/O operations.In order to realize VMX device model, we reference QEMU PC platform emulator, which is an open source project and provide most of the functions for I/O emulation. Our basic design is to run device model in the user space of domain 0, and run a process for each domain. We need to remove all the codes emulating CPU from the emulator, and modify those codes emulating physical RAM.This experiment realize a virtual Ne2000 network controller on basis of researching device model. The main work include analyze the Ne2000 logic and emulate it according...