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32 lines
602 B
NASM
32 lines
602 B
NASM
#include "config.h"
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[EXTERN syscall_handler]
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[GLOBAL syscall_gate]
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syscall_gate:
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cli
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pusha ; Pushes edi,esi,ebp,esp,ebx,edx,ecx,eax
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mov ax, ds ; Lower 16-bits of eax = ds.
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push eax ; save the data segment descriptor
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mov ax, GDT_KERNEL_DS_SELECTOR
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mov ds, ax
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mov es, ax
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mov fs, ax
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mov gs, ax
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call syscall_handler
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pop eax ; reload the original data segment descriptor
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mov ds, ax
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mov es, ax
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mov fs, ax
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mov gs, ax
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popa ; Pops edi,esi,ebp...
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sti
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iret ; pops 5 things at once: CS, EIP, EFLAGS, SS, and ESP
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