Bochs项目源码分析与注释.pdf

开源虚拟机源码分析Table of ContentChapter 1 x86 体系结构与 PC 系统概要 .....................................11．1 x86 CPU 结构...............................................................................................................11．1．1 冯诺依曼架构和 CISC 指令集......................................................................11．1．2 CPU 结构........................................................................................................11．1．3 CPU 工作模式................................................................................................21．2 x86 体系结构概览........................................................................................................31．3 PC 系统.........................................................................................................................51．3．1 PC 系统概述...................................................................................................52．3．2 总线拓扑.........................................................................................................62．3．3 存储器与 I/O 编址 .........................................................................................62．3．4 关于系统的启动与引导.................................................................................8Chapter 2 Bochs 工程概述....................................................... 112．1 开源项目 Bochs 介绍.................................................................................................112．2 版本 2.2.1 源码组织..................................................................................................112．3 工程类结构.................................................................................................................122．4 主体框架结构分析.....................................................................................................132．4．1 Bochs 工程中的重要类................................................................................13（1） VM 控制台界面类 .............................................................................................13（2） CPU 模拟............................................................................................................14（3） Memory 模拟......................................................................................................14（4）．I/O device 模拟...................................................................................................152．4．2 入口函数 main()及 Win32 Gui 初始化........................................................152．5 Bochs 的工作方式......................................................................................................18Chapter 3 CPU 类的源码分析 ...................................................203．1 CPU 类概述................................................................................................................203．1．1 CPU 逻辑结构框图......................................................................................203．1．2 类 BX_CPU_C 成员归纳.............................................................................203．2 类 BX_CPU_C 源码分析..........................................................................................213．2．1 CPU 特性声明..............................................................................................213．2．2 类 bxInstruction_c 成员分析........................................................................223．2．3 类 BX_CPU_C 源码注释.............................................................................223．3 通用寄存器.................................................................................................................293．3．1 数据结构与注释...........................................................................................293．3．2 通用寄存器归纳...........................................................................................303．4 段寄存器、全局寄存器 GDI 和 IDT ........................................................................313．4．1 数据结构与注释...........................................................................................313．4．2 段寄存器结构分析.......................................................................................333．5 CPU 状态字 EFLAGS................................................................................................353．5．1 数据结构与注释...........................................................................................35 Bochs 项目源码分析与注释 MAY 2006Understanding the source code of bochs3．5．2 源码分析.......................................................................................................393．6 函数 CPU_LOOP()结构分析.....................................................................................403．6．1 CPU_LOOP()函数总体结构........................................................................403．6．2 函数 CPU_LOOP()源码注释.......................................................................413．7 函数 handleAsyncEvent()分析...................................................................................443．7．1 函数 handleAsyncEvent()知识准备.............................................................443．7．2 函数 handleAsyncEvent()结构分析.............................................................463．7．3 函数 handleAsyncEvent()源码注释.............................................................473．8 取指与执行.................................................................................................................503．8．1 Intel IA-32 指令结构....................................................................................503．8．2 类 bxInstruction_c 的数据成员....................................................................533．8．3 取指译码函数 FetchDecode()分析 ..............................................................553．8．4 模拟指令的执行...........................................................................................59Chapter 4 CPU 中断处理任务管理............................................604．1 IA-32 体系结构中断知识准备 ..................................................................................604．1．1 中断和异常概述...........................................................................................604．1．2 异常和中断向量...........................................................................................604．1．3 中断和异常来源...........................................................................................614．1．4 与中断处理相关的数据结构.......................................................................624．1．5 异常和中断的处理方法...............................................................................644．2 Bochs 对中断的模拟..................................................................................................684．2．1 概述...............................................................................................................684．2．2 主要函数的源码注释...................................................................................694．3 虚拟机的任务管理.....................................................................................................824．3．1 IA-32 任务管理知识准备 ...........................................................................824．3．2 函数 task_switch()源码注释 ........................................................................89Chapter 5 存储器源码分析........................................................1045．1 IA-32 体系的存储器结构 ........................................................................................1045．2 Bochs 对存储器的模拟............................................................................................1055．3 存储器类 BX_MEM_C 部分源码分析...................................................................1075．3．1 相关数据结构与类定义.............................................................................1075．3．2 相关函数分析.............................................................................................1085．3 模拟分页机制...........................................................................................................1155．3．1 分页 (Paging)概述.....................................................................................1155．3．2 页目录与页表.............................................................................................1165．3．3 线形地址转换.............................................................................................1175．3．4 实现分页机制的源码分析.........................................................................120Chapter 6 系统板与外设模拟 ..................................................1366．1 Bochs 系统板描述类 bx_pc_system_c ...................................................................1366．1．1 类 bx_pc_system_c 功能概述 ....................................................................1366．1．2 PC system 定时器管理...............................................................................136 Bochs 项目源码分析与注释 MAY 2006Understanding the source code of bochs6．1．3 类 bx_pc_system_c 源码分析与注释 ........................................................1386．2 设备集合类 bx_devices_c........................................................................................1466．2．1 类 bx_devices_c 成员变量分析.................................................................1466．2．2 类 bx_devices_c 成员函数分析与注释 .....................................................1496．2．3 设备的初始化.............................................................................................1506．2．4 设备复位.....................................................................................................1546．2．5 设备访问（读写）的处理.........................................................................1556．2．6 已注册的 I/O handlers 和 IRQ 清单 ..........................................................1596．3 定时器（PIT）类分析.............................................................................................1666．3．1 类 bx_pit_c 概述.........................................................................................1666．3．2 类 bx_pit_c 源码注释.................................................................................1666．3．3 关于类 bx_virt_timer_c ..............................................................................1736．4 IDE 设备...................................................................................................................1736．4．1 磁盘控制器 controller_t .............................................................................1736．4．2 IDE 驱动器描述类 bx_hard_drive_c .........................................................1746．4．3 读写磁盘映象.............................................................................................1756．4．4 ATA/IDE 控制器（通道）和设备初始化.................................................1766．4．5 ATA 控制器的寄存器读写 ........................................................................1846．4．6 CD ROM 设备............................................................................................1936．5 PCI 子系统 ...............................................................................................................2036．5．1 PCI 概述 .....................................................................................................2036．5．2 PCI 主桥描述类 bx_pci_c 分析.................................................................2096．6 VGA 设备模拟.........................................................................................................2156．6．1 模拟 VGA 的类..........................................................................................2156．6．2 VGA 在 svga_timer 中的更新 ...................................................................216Appendix ...................................................................................217Appendix A．Bochs 配置文本说明 ....................................................................................217Appendix B．ATA 和 ATAPI 编程介绍.............................................................................225Appendix C．Sound Blaster 16 编程...................................................................................230Appendix D．VESA 编程介绍............................................................................................240Appendix E．Bochs 上运行的操作系统示范.....................................................................261