26 lines
538 B
C
26 lines
538 B
C
#ifndef GDT_H
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#define GDT_H
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#include <stdint.h>
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// We're using the GDT for segmentation, but as we want to target Long Mode,
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// we'll only use this as a requirement for paging, not more.
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// This means base 0 and no limit (whole address space)
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#define NUM_GDT_ENTRIES 5
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#define NULL_SELECTOR 0x00
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#define KERNEL_CODE_SEGMENT 0x08
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#define KERNEL_DATA_SEGMENT 0x10
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#define USER_CODE_SEGMENT 0x18
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#define USER_DATA_SEGMENT 0x20
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struct GDTR
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{
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uint16_t limit;
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uint64_t address;
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} __attribute__((packed));
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void gdt_init();
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#endif |