Research And Optimization On Device Driver Based On Micro-kernel Virtualization

With the popularity of embedded devices and increasing requirements from users, the utilization of their resources is becoming an obvious problem.The complicated embedded system, in great demand of efficiency, security and reliability, makes embedded virtualization solutions become the hot topic. The performance and high reliability greatly depend on the device virtualization, which is the key technology of virtualization solution.In this paper, present device driver models are analyzed, focusing on the advantages, disadvantages and the occasion. To meet the special requirements of embedded devices, the L4/Fiasco micro-kernel as the basic virtualization solution is introduced, and a new device driver model designed is presented with the optimized reliability, security, efficiency and portability. The server module is divided into fine grained component to decoupling its reliance with the applications, and hardware devices, simplifying the Client/Server implementation for portability while providing the reliability. Also, a fast recovery mechanism is designed for servers to enhance system reliability. In this model, we made full use of the capability mechanism to implement the access control examination. With the help of IPC mechanism provided by kernel, a fast data transmission improving the performance greatly, was achieved by transmitting data with shared memory based on address space mechanism, shorting communications path and reducing data copies.At last, a NAND FLASH driver is optimized with the above solution, and implemented on Devkit8000. Experiment shows that the proposal provides driver service with efficiency, security and reliability.