系统相关
首页 > 系统相关> > Linux 内核中断体系结构 (1)

Linux 内核中断体系结构 (1)

作者:互联网

@

目录

0. 目的:

1.硬件的中断响应 ---> 内核驱动中的中断
2.系统调用的函数响应(sys call) --->系统调用
3.自定义中断 --->软件的软中断模式
4.信号中断 (kill -signalnum)
5.系统的异常和错误 ---> 系统异常处理获取 了解系统异常的作用

1. Linux的中断机制

1.1 分类:

硬件中断 软件中断
硬中断:由电脑主机的8259A类似的硬件中断控制芯片发出的中断
AR中断控制器发出的中断
软中断:异常第一类:CPU自行保留的中断
系统调用异常

1.2 代码结构:

asm.s -> trap.c
system_call.s -> fork.c signal.c exit.c sys.c

2. 中断的工作流程:

2.1: 回忆

2.2 Linux 中中断的工作流程

如图所示:
         中断前的处理过程,中断的回复过程   中断的执行过程

硬件中断的处理过程  asm.s                trap.c
软件及系统调用的处理过程 system call.s            fork.csignal .cexit.c sys.c

3. 中断的代码实现过程

         中断前的处理过程,中断的回复过程   中断的执行过程
硬件中断的处理过程  asm.s                trap.c

EIP寄存器,用来存储CPU要读取指令的地址,CPU通过EIP寄存器读取即将要执行的指令。每次CPU执行完相应的汇编指令之后,EIP寄存器的值就会增加。

老师说的其实不准确,实际上是eax和(esp指向的内存)两个东西交换了,esp存的是内存地址,而加括号就是取这个地址对应的内存值,并不是操作的esp

CS(code segment)代码段地址寄存器,存放代码段的起始地址

DS(data segment)数据段地址寄存器,存放数据段的起始地址

SS(stack segment)堆栈段地址寄存器,存放堆栈段的起始地址(每个进程都有自己的栈空间)

ES(extra segment)附加段地址寄存器,存放附加段的起始地址

linux错误码汇总链接
在这里插入图片描述

/*
 *  linux/kernel/asm.s
 *
 *  (C) 1991  Linus Torvalds
 */

/*
 * asm.s contains the low-level code for most hardware faults.
 * page_exception is handled by the mm, so that isn't here. This
 * file also handles (hopefully) fpu-exceptions due to TS-bit, as
 * the fpu must be properly saved/resored. This hasn't been tested.
 */

.globl _divide_error,_debug,_nmi,_int3,_overflow,_bounds,_invalid_op
.globl _double_fault,_coprocessor_segment_overrun
.globl _invalid_TSS,_segment_not_present,_stack_segment
.globl _general_protection,_coprocessor_error,_irq13,_reserved

_divide_error:
	pushl $_do_divide_error//把一个c语言函数入栈
no_error_code://无错误码中断
	xchgl %eax,(%esp) // 此时%esp指向的地址里面的值是$_do_divide_error 的函数地址 
	pushl %ebx   
	pushl %ecx
	pushl %edx
	pushl %edi
	pushl %esi
	pushl %ebp
	push %ds
	push %es
	push %fs
	pushl $0		# "error code"
	lea 44(%esp),%edx
	pushl %edx
	movl $0x10,%edx
	mov %dx,%ds
	mov %dx,%es
	mov %dx,%fs
	call *%eax
	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://这是一个中断
	pushl $_do_int3		# _do_debug
	jmp no_error_code//跳转

_nmi:
	pushl $_do_nmi
	jmp no_error_code

_int3:
	pushl $_do_int3
	jmp no_error_code

_overflow:
	pushl $_do_overflow
	jmp no_error_code

_bounds:
	pushl $_do_bounds
	jmp no_error_code

_invalid_op:
	pushl $_do_invalid_op
	jmp no_error_code

_coprocessor_segment_overrun:
	pushl $_do_coprocessor_segment_overrun
	jmp no_error_code

_reserved:
	pushl $_do_reserved
	jmp no_error_code

_irq13:
	pushl %eax
	xorb %al,%al
	outb %al,$0xF0
	movb $0x20,%al
	outb %al,$0x20
	jmp 1f
1:	jmp 1f
1:	outb %al,$0xA0
	popl %eax
	jmp _coprocessor_error

_double_fault:
	pushl $_do_double_fault
error_code://有中断码中断
	xchgl %eax,4(%esp)		# error code <-> %eax
	xchgl %ebx,(%esp)		# &function <-> %ebx
	pushl %ecx
	pushl %edx
	pushl %edi
	pushl %esi
	pushl %ebp
	push %ds
	push %es
	push %fs
	pushl %eax			# error code
	lea 44(%esp),%eax		# offset
	pushl %eax
	movl $0x10,%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

_invalid_TSS:
	pushl $_do_invalid_TSS
	jmp error_code

_segment_not_present:
	pushl $_do_segment_not_present
	jmp error_code

_stack_segment:
	pushl $_do_stack_segment
	jmp error_code

_general_protection:
	pushl $_do_general_protection
	jmp error_code

trap.c

/*
 *  linux/kernel/traps.c
 *
 *  (C) 1991  Linus Torvalds
 */

/*
 * 'Traps.c' handles hardware traps and faults after we have saved some
 * state in 'asm.s'. Currently mostly a debugging-aid, will be extended
 * to mainly kill the offending process (probably by giving it a signal,
 * but possibly by killing it outright if necessary).
 */
#include <string.h>

#include <linux/head.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/io.h>

#define get_seg_byte(seg,addr) ({ \
register char __res; \
__asm__("push %%fs;mov %%ax,%%fs;movb %%fs:%2,%%al;pop %%fs" \
	:"=a" (__res):"0" (seg),"m" (*(addr))); \
__res;})

#define get_seg_long(seg,addr) ({ \
register unsigned long __res; \
__asm__("push %%fs;mov %%ax,%%fs;movl %%fs:%2,%%eax;pop %%fs" \
	:"=a" (__res):"0" (seg),"m" (*(addr))); \
__res;})

#define _fs() ({ \
register unsigned short __res; \
__asm__("mov %%fs,%%ax":"=a" (__res):); \
__res;})

int do_exit(long code);

void page_exception(void);

void divide_error(void);
void debug(void);
void nmi(void);
void int3(void);
void overflow(void);
void bounds(void);
void invalid_op(void);
void device_not_available(void);
void double_fault(void);
void coprocessor_segment_overrun(void);
void invalid_TSS(void);
void segment_not_present(void);
void stack_segment(void);
void general_protection(void);
void page_fault(void);
void coprocessor_error(void);
void reserved(void);
void parallel_interrupt(void);
void irq13(void);

//esp_ptr 段指针
//nr 出错的段号
//总的来说die函数就是用来打印错误信息
static void die(char * str,long esp_ptr,long nr)
{
	long * esp = (long *) esp_ptr;
	int i;
	//以下基本在打印栈信息
	printk("%s: %04x\n\r",str,nr&0xffff);
	printk("EIP:\t%04x:%p\nEFLAGS:\t%p\nESP:\t%04x:%p\n",
		esp[1],esp[0],esp[2],esp[4],esp[3]);
	printk("fs: %04x\n",_fs());
	printk("base: %p, limit: %p\n",get_base(current->ldt[1]),get_limit(0x17));
	if (esp[4] == 0x17) {
		printk("Stack: ");
		for (i=0;i<4;i++)
			printk("%p ",get_seg_long(0x17,i+(long *)esp[3]));
		printk("\n");
	}
	str(i);
	printk("Pid: %d, process nr: %d\n\r",current->pid,0xffff & i);
	for(i=0;i<10;i++)
		printk("%02x ",0xff & get_seg_byte(esp[1],(i+(char *)esp[0])));
	printk("\n\r");
	do_exit(11);//退出中断		/* play segment exception */
}

void do_double_fault(long esp, long error_code)
{
	die("double fault",esp,error_code);
}

void do_general_protection(long esp, long error_code)
{
	die("general protection",esp,error_code);
}
//asm.s调用的第一个函数在这里
void do_divide_error(long esp, long error_code)
{
	die("divide error",esp,error_code);
}

void do_int3(long * esp, long error_code,
		long fs,long es,long ds,
		long ebp,long esi,long edi,
		long edx,long ecx,long ebx,long eax)
{
	int tr;

	__asm__("str %%ax":"=a" (tr):"0" (0));
	printk("eax\t\tebx\t\tecx\t\tedx\n\r%8x\t%8x\t%8x\t%8x\n\r",
		eax,ebx,ecx,edx);
	printk("esi\t\tedi\t\tebp\t\tesp\n\r%8x\t%8x\t%8x\t%8x\n\r",
		esi,edi,ebp,(long) esp);
	printk("\n\rds\tes\tfs\ttr\n\r%4x\t%4x\t%4x\t%4x\n\r",
		ds,es,fs,tr);
	printk("EIP: %8x   CS: %4x  EFLAGS: %8x\n\r",esp[0],esp[1],esp[2]);
}

void do_nmi(long esp, long error_code)
{
	die("nmi",esp,error_code);
}

void do_debug(long esp, long error_code)
{
	die("debug",esp,error_code);
}

void do_overflow(long esp, long error_code)
{
	die("overflow",esp,error_code);
}

void do_bounds(long esp, long error_code)
{
	die("bounds",esp,error_code);
}

void do_invalid_op(long esp, long error_code)
{
	die("invalid operand",esp,error_code);
}

void do_device_not_available(long esp, long error_code)
{
	die("device not available",esp,error_code);
}

void do_coprocessor_segment_overrun(long esp, long error_code)
{
	die("coprocessor segment overrun",esp,error_code);
}

void do_invalid_TSS(long esp,long error_code)
{
	die("invalid TSS",esp,error_code);
}

void do_segment_not_present(long esp,long error_code)
{
	die("segment not present",esp,error_code);
}

void do_stack_segment(long esp,long error_code)
{
	die("stack segment",esp,error_code);
}

void do_coprocessor_error(long esp, long error_code)
{
	if (last_task_used_math != current)
		return;
	die("coprocessor error",esp,error_code);
}

void do_reserved(long esp, long error_code)
{
	die("reserved (15,17-47) error",esp,error_code);
}

//中断的初始化函数
//set_trap_gate 优先级较低 只能由用户程序来调用
//set_system_gate 优先级很高 能由系统和用户所有的程序调用
void trap_init(void)
{
	int i;

	set_trap_gate(0,&divide_error);//如果被除数是0就会产生这个中断
	set_trap_gate(1,&debug);//单步调试的时候调用这个中断
	set_trap_gate(2,&nmi);
	set_system_gate(3,&int3);	/* int3-5 can be called from all */
	set_system_gate(4,&overflow);
	set_system_gate(5,&bounds);
	set_trap_gate(6,&invalid_op);
	set_trap_gate(7,&device_not_available);
	set_trap_gate(8,&double_fault);
	set_trap_gate(9,&coprocessor_segment_overrun);
	set_trap_gate(10,&invalid_TSS);
	set_trap_gate(11,&segment_not_present);
	set_trap_gate(12,&stack_segment);
	set_trap_gate(13,&general_protection);
	set_trap_gate(14,&page_fault);
	set_trap_gate(15,&reserved);
	set_trap_gate(16,&coprocessor_error);
	for (i=17;i<48;i++)
		set_trap_gate(i,&reserved);
	set_trap_gate(45,&irq13);
	outb_p(inb_p(0x21)&0xfb,0x21);
	outb(inb_p(0xA1)&0xdf,0xA1);
	set_trap_gate(39,&parallel_interrupt);
}

标签:code,esp,中断,void,error,内核,Linux,pushl,体系结构
来源: https://www.cnblogs.com/dcj101404/p/15975128.html