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#ifndef DEF_GDT_H
#define DEF_GDT_H
#include <types.h>
struct gdt_entry {
uint16_t limit_low;
uint16_t base_low;
uint8_t base_middle;
uint8_t access;
uint8_t granularity;
uint8_t base_high;
} __attribute__((packed));
struct gdt_ptr {
uint16_t limit;
uint32_t base;
} __attribute__((packed));
struct tss_entry {
uint32_t prev_tss; // The previous TSS - if we used hardware task switching this would form a linked list.
uint32_t esp0; // The stack pointer to load when we change to kernel mode.
uint32_t ss0; // The stack segment to load when we change to kernel mode.
uint32_t esp1; // Unused...
uint32_t ss1;
uint32_t esp2;
uint32_t ss2;
uint32_t cr3;
uint32_t eip;
uint32_t eflags;
uint32_t eax;
uint32_t ecx;
uint32_t edx;
uint32_t ebx;
uint32_t esp;
uint32_t ebp;
uint32_t esi;
uint32_t edi;
uint32_t es; // The value to load into ES when we change to kernel mode.
uint32_t cs; // The value to load into CS when we change to kernel mode.
uint32_t ss; // The value to load into SS when we change to kernel mode.
uint32_t ds; // The value to load into DS when we change to kernel mode.
uint32_t fs; // The value to load into FS when we change to kernel mode.
uint32_t gs; // The value to load into GS when we change to kernel mode.
uint32_t ldt; // Unused...
uint16_t trap;
uint16_t iomap_base;
} __attribute__((packed));
void gdt_init();
void gdt_setKernelStack(uint32_t esp0);
#endif
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