Linux1.0内核中断体系的建立

head.S中设置了IDT的指针，共256项，都指向ignore_int函数

ignore_int:
cld
pushl %eax
pushl %ecx
pushl %edx
push %ds
push %es
push %fs
movl $(KERNEL_DS),%eax
mov %ax,%ds
mov %ax,%es
mov %ax,%fs
pushl $int_msg
call _printk
popl %eax
pop %fs
pop %es
pop %ds
popl %edx
popl %ecx
popl %eax
iret

而在Traps.c文件中，对可能出现的异常进行初始化

void trap_init(void)
{
int i;

set_trap_gate(0,÷_error);
set_trap_gate(1,&debug);
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);
set_trap_gate(17,&alignment_check);
for (i=18;i<48;i++)
set_trap_gate(i,&reserved);
}

至于硬件设备产生的中断，Linux1.0内核专门建立了对应的函数调用表，当产生中断则调用相应的函数。在IRQ.c文件中处理。

void init_IRQ(void)
{
int i;

//初始化16个中断执行函数，初始化16个中断处理
for (i = 0; i < 16 ; i++)
set_intr_gate(0x20+i,bad_interrupt[i]);

//挂接2号，2号为连接从芯片，不执行任何事
if (irqaction(2,&ignore_IRQ))
printk("Unable to get IRQ2 for cascade\n");

//挂接irq与math操作，数学协处理器中断
if (request_irq(13,math_error_irq))
printk("Unable to get IRQ13 for math-error handler\n");

/* intialize the bottom half routines. */
for (i = 0; i < 32; i++) {
bh_base[i].routine = NULL;
bh_base[i].data = NULL;
}
bh_active = 0;
intr_count = 0;
}