基于页表机制实现QEMU调用片外外设动态库的方法OA

This paper investigates the page table mechanism for address translation between the QEMU virtual machine and the host,providing an in-depth analysis of page table filling principles and how memory read/write instructions trigger distinct processing flows for different memory types.By introducing a new flag bit into page attributes and setting/checking this bit during page table population and in memory access helper functions,the method achieves recognition of addresses with specific attributes and invokes corresponding call-back functions.With reference to the peripheral addition process in the QEMU leon3 example,interface functions for dynamic libraries are designed,including device creation,initialization,and read/write callbacks.The read/write process and parameter transmission characteristics of QEMU for MMIO peripherals are analyzed to clarify the peripheral locating principle and the basic parameters required by callback functions.Based on this,precise call locations for read/write callback functions in off-chip MMIO peripheral dynamic libraries are designed and presented.Experiments verify the correctness and performance sensitivity of the proposed approach.Results demonstrate that this method effectively separates peripheral code from QEMU source code,ensures correct execution,and achieves over 97%of the performance compared to compiling peripheral source code directly with QEMU.This study offers valuable insights for virtual machine developers and QEMU open-source users.