asm.s

jhluroom

/*
* 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
no_error_code:
    xchgl %eax,(%esp)
    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:
    pushl $_do_int3        # _do_debug
    jmp no_error_code
_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:
    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


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