reimplements the gdt

kernel/arch/gdt/gdt.s

@@ -0,0 +1,23 @@
+gdtr 	DW 0 ; limit store
+	DD 0 ; base storage
+
+global setGdt
+setGdt:
+	mov ax, [esp + 4]
+	mov [gdtr], ax
+	mov eax, [esp + 8]
+	mov [gdtr + 2], eax
+	lgdt [gdtr]
+	ret
+
+global reloadSegments
+reloadSegments:
+	jmp 0x08:.reload_CS ; 0x08 is a stand in for the code segment
+.reload_CS:
+	mov ax, 0x10 ; stand in for the data segment
+	mov ds, ax
+	mov es, ax
+	mov fs, ax
+	mov gs, ax
+	mov ss, ax
+	ret

kernel/arch/gdt/gdt_entry.c

@@ -0,0 +1,19 @@
+#include <kernel/x86/gdt.h>
+
+uint64_t create_descriptor(uint32_t base, uint32_t limit, uint16_t flag)
+{
+	uint64_t descriptor;
+
+	descriptor = limit & 0x000F0000;
+	descriptor |= (flag << 8) & 0x00F0FF00;
+	descriptor |= (base >> 16) & 0x000000FF;
+	descriptor |= base & 0xFF000000;
+
+	descriptor <<= 32;
+
+	descriptor |= base << 16;
+	descriptor |= limit & 0x0000FFFF;
+
+	return descriptor;
+}
+