36 lines
765 B
C
36 lines
765 B
C
#pragma once
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#include <stdint.h>
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#define NULL_SEGMENT 0
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#define KERNEL_CODE_SEGMENT 1
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#define KERNEL_DATA_SEGMENT 2
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#define USER_CODE_SEGMENT 3
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#define USER_DATA_SEGMENT 4
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#define TASK_STATE_SEGMENT 5
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struct SegmentDescriptor {
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unsigned short limit_low;
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unsigned short base_low;
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unsigned char base_middle;
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unsigned char access;
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unsigned char granularity;
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unsigned char base_high;
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}__attribute__((packed));
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extern SegmentDescriptor GlobalDescriptorTable[6];
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struct GlobalDescriptorTableDescriptor{
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unsigned short limit;
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unsigned int base;
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}__attribute__((packed)) ;
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void add_descriptor(int which , unsigned long base, unsigned long limit, unsigned char access, unsigned char granularity );
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void initGDT();
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