50 lines
988 B
ArmAsm
50 lines
988 B
ArmAsm
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#include <memlayout.h>
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# vectors.S sends all traps here.
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.text
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.globl __alltraps
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__alltraps:
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# push registers to build a trap frame
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# therefore make the stack look like a struct trapframe
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pushl %ds
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pushl %es
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pushl %fs
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pushl %gs
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pushal
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# load GD_KDATA into %ds and %es to set up data segments for kernel
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movl $GD_KDATA, %eax
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movw %ax, %ds
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movw %ax, %es
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# push %esp to pass a pointer to the trapframe as an argument to trap()
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pushl %esp
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# call trap(tf), where tf=%esp
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call trap
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# pop the pushed stack pointer
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popl %esp
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# return falls through to trapret...
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.globl __trapret
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__trapret:
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# restore registers from stack
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popal
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# restore %ds, %es, %fs and %gs
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popl %gs
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popl %fs
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popl %es
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popl %ds
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# get rid of the trap number and error code
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addl $0x8, %esp
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iret
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.globl forkrets
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forkrets:
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# set stack to this new process's trapframe
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movl 4(%esp), %esp
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jmp __trapret
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