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/* Segment indexes. Must match the gdt definition in segment.c. */
enum {
NULL_SEG,
FLAT_CODE,
FLAT_DATA,
RELOC_CODE,
RELOC_DATA,
NUM_SEG,
};
/* Values for segment selector register */
#define FLAT_CS (FLAT_CODE << 3)
#define FLAT_DS (FLAT_DATA << 3)
#define RELOC_CS (RELOC_CODE << 3)
#define RELOC_DS (RELOC_DATA << 3)
/* i386 segment descriptor */
struct segment_desc {
unsigned short limit_0;
unsigned short base_0;
unsigned char base_16;
unsigned char types;
unsigned char flags;
unsigned char base_24;
};
extern struct segment_desc gdt[NUM_SEG];
#define GDT_LIMIT ((NUM_SEG << 3) - 1)
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