A update

include/gdt.h

@@ -0,0 +1,23 @@
+#ifndef _GDT_H
+#define _GDT_H
+
+#include <stdint.h>
+
+struct gdt_entry {
+    uint16_t limit_low;     /* Lower 16 bits of limit */
+    uint16_t base_low;      /* Lower 16 bits of base */
+    uint8_t  base_middle;   /* Next 8 bits of base */
+    uint8_t  access;        /* Access flags */
+    uint8_t  granularity;   /* Granularity + high 4 bits of limit */
+    uint8_t  base_high;     /* Last 8 bits of base */
+} __attribute__((packed));
+
+struct gdt_ptr {
+    uint16_t limit;   /* Size of GDT - 1 */
+    uint32_t base;    /* Base address of GDT */
+} __attribute__((packed));
+
+void gdt_install();
+void gdt_set_entry(int num, uint32_t base, uint32_t limit, uint8_t access, uint8_t gran);
+
+#endif