Added basic paging.h & paging.c

kernel/include/paging.h

@@ -0,0 +1,25 @@
+#ifndef _PAGING_H
+#define _PAGING_H
+
+#include <kernel.h>
+
+#define PAGE_SIZE	4096
+
+#define PHYS_ADDR(_a)	((_a) & ~0xfff)
+
+#define PAGE_FLAG_PRESENT	(1 << 0)
+#define PAGE_FLAG_WRITE		(1 << 1)
+#define PAGE_FLAG_USER		(1 << 2)
+#define PAGE_FLAG_PWT		(1 << 3)
+#define PAGE_FLAG_NOCACHE	(1 << 4)
+#define PAGE_FLAG_ACCESSED	(1 << 5)
+#define PAGE_FLAG_DIRTY		(1 << 6)
+#define PAGE_FLAG_4MB		(1 << 7)
+#define PAGE_FLAG_GLOBAL	(1 << 8)
+
+// Defined in entry.s for initial paging
+extern uint32_t init_pagedir[1024];
+
+int pag_init(void);
+
+#endif