Add assembly library to enable paging

src/makefile

@@ -2,6 +2,7 @@ C=/home/adam/college/kernel/cross/bin/i686-elf-gcc
 
 all:
 	/usr/bin/nasm -felf32 head.asm -o boot.o
+	/usr/bin/nasm -felf32 paging.asm
 	$C *.c -std=gnu99 -ffreestanding -O2 -Wall -Wextra -c
 	$C -T linker.ld -o myos.bin -ffreestanding -O2 -nostdlib *.o -lgcc
 

src/mem.h

@@ -5,6 +5,10 @@
 #pragma once
 #include <stdint.h>
 
+// These two are defined in the assembly file paging.asm
+extern void loadPageDirectory(uint32_t*);
+extern void enablePaging();
+
 // Defined in the file mem.c
 uint32_t* initiate_directory();
  void initiate_page_table(uint32_t* page_dir);

src/paging.asm

+section .text
+	global loadPageDirectory
+
+loadPageDirectory:
+	push ebp
+	mov ebp, esp
+	mov eax, [esp+8]
+	mov cr3, eax
+	mov esp, ebp
+	pop ebp
+	ret
+
+	global enablePaging
+enablePaging:
+	push ebp
+	mov ebp, esp
+	mov eax, cr0
+	or eax, 0x80000000
+	mov cr0, eax
+	mov esp, ebp
+	pop ebp
+	ret