1 files changed, 55 insertions, 0 deletions
diff --git a/arch/i386/include/kernel/gdt.h b/arch/i386/include/kernel/gdt.h
new file mode 100644
index 0000000..532881a
--- /dev/null
+++ b/arch/i386/include/kernel/gdt.h
@@ -0,0 +1,55 @@
+#ifndef I386_GDT_H
+#define I386_GDT_H
+
+#include <stdint.h>
+
+struct gdt_entry {
+        uint16_t limit_low;
+        uint16_t base_low;
+        uint8_t base_middle;
+        uint8_t access;
+        uint8_t gran;
+        uint8_t base_high;
+} __attribute__((packed));
+
+struct gdt_ptr {
+        uint16_t limit;
+        uint32_t base;
+} __attribute__((packed));
+
+struct tss_entry {
+        uint32_t link;
+        uint32_t esp0;
+        uint32_t ss0;
+        uint32_t esp1;
+        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;
+        uint32_t cs;
+        uint32_t ss;
+        uint32_t ds;
+        uint32_t fs;
+        uint32_t gs;
+        uint32_t ldtr;
+        uint16_t trap;
+        uint16_t iomap_base;
+} __attribute__((packed));
+
+void gdt_set_gate(int num, uint32_t base, uint32_t limit, uint8_t access, uint8_t gran);
+void write_tss(int num, uint32_t ss0, uint32_t esp0);
+void set_kernel_esp(uint32_t esp);
+void gdt_install(void);
+
+void flush_gdt(void);
+
+#endif