中断处理有三个阶段

进入阶段：栈保存(带出错码的中断、不带出错码的中断)

处理阶段：中断处理

退出阶段：恢复栈

80×86中有特权级的概念，不同的特权级有不同的栈，所以中断发生时要保存中断前的栈地址。

查看intel使用手册

interrupt.s源代码文件(参考linux 0.11源代码)

.global divide_error,debug_exception,nmi,breakpoint,overflow,bound,invalid_opcode

.global coprocessor_not_available,double_fault,coprocessor_segment_overrun,invalid_tss

.global segment_not_present,stack_exception,protection_exception,page_fault

.global intel_reserved,coprecessor_error,default_isr,timer

.include "kernel.inc"

divide_error:

pushl $do_divide_error

no_error_code:

xchgl %eax, (%esp) # &function-> %eax, 原%eax放到栈中

pushl %ebx

pushl %ecx

pushl %edx

pushl %edi

pushl %esi

pushl %ebp

push %ds

push %es

push %fs

pushl $0 # 填充错误码,作为中断处理函数的参数

lea 52(%esp), %edx #当前堆栈地址加上52后，放到edx中

pushl %edx #压edx入栈，这样中断处理函数就能获取到被压入栈的寄存器的值

movl $DATA_SEL, %edx

mov %dx, %ds

mov %dx, %es

mov %dx, %fs

call *%eax #调用中断处理函数

addl $8, %esp

pop %fs

pop %es

pop %ds

popl %ebp

popl %esi

popl %edi

popl %edx

popl %ecx

popl %ebx

popl %eax

iret

invalid_tss:

pushl $do_invalid_tss

error_code:

xchgl %eax, 4(%esp) # error code -> %eax, 原eax放到栈中

xchgl %ebx, (%esp) # &function -> %ebx，原ebx放到栈中

pushl %ecx

pushl %edx

pushl %edi

pushl %esi

pushl %ebp

pushl %ds

pushl %es

pushl %fs

pushl %eax # 压入错误码，作为中断处理函数的参数

lea 52(%esp), %eax # 当前堆栈地址加上52后，放到eax中

pushl %eax # 压eax入栈，这样中断处理函数就能获取到被压入栈的寄存器的值

movl $DATA_SEL, %eax

mov %ax, %ds

mov %ax, %es

mov %ax, %fs

call *%ebx

addl $8, %esp

pop %fs

pop %es

pop %ds

popl %ebp

popl %esi

popl %edi

popl %edx

popl %ecx

popl %ebx

popl %eax

iret

debug_exception:

pushl $do_debug_exception

jmp no_error_code

nmi:

pushl $do_nmi

jmp no_error_code

breakpoint:

pushl $do_breakpoint

jmp no_error_code

overflow:

pushl $do_overflow

jmp no_error_code

bound:

pushl $do_bound

jmp no_error_code

invalid_opcode:

pushl $do_invalid_opcode

jmp no_error_code

coprocessor_not_available:

pushl $do_coprocessor_not_available

jmp no_error_code

coprocessor_segment_overrun:

pushl $do_coprocessor_segment_overrun

jmp no_error_code

intel_reserved:

pushl $do_intel_reserved

jmp no_error_code

coprecessor_error:

pushl $do_coprocessor_error

jmp no_error_code

timer:

pushl $do_timer

jmp no_error_code

double_fault:

pushl $do_double_fault

jmp error_code

invaild_tss:

pushl $do_invalid_tss

jmp error_code

segment_not_present:

pushl $do_segment_not_present

jmp error_code

stack_exception:

pushl $do_stack_exception

jmp error_code

protection_exception:

pushl $do_protection_exception

jmp error_code

page_fault:

pushl $do_page_fault

jmp error_code

default_isr:

pushl $do_default_isr

jmp no_error_code

interrupt.h源代码文件

#ifndef _INTERRUPT_H_

#define _INTERRUPT_H_

//在中断处理函数中，每个寄存器在栈中的下标

#define OLD_SS_REG 2

#define OLD_ESP_REG 1

#define OLD_EFLAGS_REG 0

#define OLD_CS_REG -1

#define OLD_EIP_REG -2

#define EAX_REG -3

#define EBX_REG -4

#define ECX_REG -5

#define EDX_REG -6

#define EDI_REG -7

#define ESI_REG -8

#define EBP_REG -9

#define DS_REG -10

#define ES_REG -11

#define FS_REG -12

extern void default_isr(void); //该函数定义在idt.c文件中

extern void divide_error(void);

extern void debug_exception(void);

extern void nmi(void);

extern void breakpoint(void);

extern void overflow(void);

extern void bound(void);

extern void invalid_opcode(void);

extern void coprocessor_not_available(void);

extern void double_fault(void);

extern void coprocessor_segment_overrun(void);

extern void invalid_tss(void);

extern void segment_not_present(void);

extern void stack_exception(void);

extern void protection_exception(void);

extern void page_fault(void);

extern void intel_reserved(void);

extern void coprecessor_error(void);

extern void timer(void);

extern void sys_call(void);

#endif