49 lines
1.2 KiB
C
49 lines
1.2 KiB
C
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/*
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File: gdt.H
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Author: R. Bettati
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Department of Computer Science
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Texas A&M University
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Date : 09/03/02
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Description: Management of the Global Descriptor Table (GDT)
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The GDT describes memory access priviledges for memory segments.
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While the table is initialized by GRUB already, it may be a good idea to
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do this again in the kernel code.
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For details see Section 5 of Brandon Friesen's Tutotial
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on OS Kernel Development.
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URL: http://www.osdever.net/bkerndev/Docs/title.htm
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*/
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#ifndef _GDT_H_ // include file only once
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#define _GDT_H_
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/*--------------------------------------------------------------------------*/
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/* GDT */
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/*--------------------------------------------------------------------------*/
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class GDT {
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private:
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/* Use this function to set up an entry in the GDT. */
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static void set_gate(int num,
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unsigned long base, unsigned long limit,
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unsigned char access, unsigned char gran);
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public:
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static const unsigned int SIZE = 3;
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static void init();
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/* Initialize the GDT to have a null segment, a code segment,
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and one data segment. */
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};
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#endif
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