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.global int0
.global int1
.global int2
.global int3
.global int4
.global int5
.global int6
.global int7
.global int8
.global int9
.global int10
.global int11
.global int12
.global int13
.global int14
.global int15
.global int128
.global int129
.global int255
.global exc0
.global exc1
.global exc2
.global exc3
.global exc4
.global exc5
.global exc6
.global exc7
.global exc8
.global exc9
.global exc10
.global exc11
.global exc12
.global exc13
.global exc14
.global exc15
.global exc16
.global exc17
.global exc18
// nothing to ack
.macro ack0
.endm
// ack master
.macro ack1
push %eax // persist
mov $0x20,%al
out %al,$0x20
pop %eax // load original
.endm
// ack master and servant
.macro ack2
push %eax // persist
mov $0x20,%al
out %al,$0xa0 // slave
out %al,$0x20 // master
pop %eax // load original
.endm
.macro intx ack num func
/*
Once we arrived here the stack already contains 3x 32bit values,
which will be poped by 'iret'
- eflags
- return code segment selector
- return instruction pointer
There are two possiblities concerning our stack position:
a) if the interrupt occured while kernel code was executed we are
on the same stack and have no clue about the stack alignment
b) if the interrupt occured while user code was executed the
configured tss.esp0 was used, in this case we are at the start
of the esp0 stack.
*/
\ack //acknowledge interrupt
//also remember that we will get new interrupts only
//after iret or reenabling themn explicitly!
push $0x666 //make room for potential C functions 'return value'.
//we use eax already for esp (so we can context switch)
push $0x0 //indicate if we want to return the value in ebx 0x0=NO
pusha //Push all standard registers 8 regs x 4bytes/32bit
push %ds //Push data segment
push %es //etc...
push %fs
push %gs
mov %esp,%eax // remember THIS stack position
and $-16,%esp // padding to align stack on 16byte boundary before CALL
sub $8,%esp // ...
push \num // pass in this interrupt number
push %eax // pass in original %esp (saved just few lines before)
call \func
mov %eax,%esp // use the %esp we got from c function
pop %gs // pop everything back...
pop %fs // ...
pop %es
pop %ds
popa
cmp $0x0,(%esp)
je skip\num
pop %ebx
pop %ebx
jmp ret\num
skip\num:
add $8,%esp // potentially set return value to eax to return to the caller
ret\num:
iret // pops the return instruction pointer, return code segment selector, and EFLAGS image from the stack
.endm
.macro excx func
call \func
jmp .
.endm
int0: intx ack1 $0 interrupt_handler
int1: intx ack1 $1 interrupt_handler
int2: intx ack1 $2 interrupt_handler
int3: intx ack1 $3 interrupt_handler
int4: intx ack1 $4 interrupt_handler
int5: intx ack1 $5 interrupt_handler
int6: intx ack1 $6 interrupt_handler
int7: intx ack1 $7 interrupt_handler
int8: intx ack2 $8 interrupt_handler
int9: intx ack2 $9 interrupt_handler
int10: intx ack2 $10 interrupt_handler
int11: intx ack2 $11 interrupt_handler
int12: intx ack2 $12 interrupt_handler
int13: intx ack2 $13 interrupt_handler
int14: intx ack2 $14 interrupt_handler
int15: intx ack2 $15 interrupt_handler
int128: intx ack0 $128 interrupt_handler
int129: intx ack0 $129 interrupt_handler
int255: intx ack0 $255 interrupt_handler
exc0: excx exception_handle_0
exc1: excx exception_handle_1
exc2: excx exception_handle_2
exc3: excx exception_handle_3
exc4: excx exception_handle_4
exc5: excx exception_handle_5
exc6: excx exception_handle_6
exc7: excx exception_handle_7
exc8: excx exception_handle_8
exc9: excx exception_handle_9
exc10: excx exception_handle_10
exc11: excx exception_handle_11
exc12: excx exception_handle_12
exc13: excx exception_handle_13
exc14: excx exception_handle_14
exc15: excx exception_handle_15
exc16: excx exception_handle_16
exc17: excx exception_handle_17
exc18: excx exception_handle_18
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