Index: kernel/generic/include/mm/mm.h
===================================================================
--- kernel/generic/include/mm/mm.h	(revision 67f11a04d9b9007cff6be59c182bd35c4f3ee076)
+++ kernel/generic/include/mm/mm.h	(revision 6be2c13c42be6b2f450ca654c0b1f32fb186f909)
@@ -37,27 +37,15 @@
 
 #define PAGE_CACHEABLE_SHIFT		0
-#define PAGE_NOT_CACHEABLE_SHIFT	PAGE_CACHEABLE_SHIFT
-#define PAGE_PRESENT_SHIFT		1
-#define PAGE_NOT_PRESENT_SHIFT		PAGE_PRESENT_SHIFT
+#define PAGE_NOT_PRESENT_SHIFT		1
 #define PAGE_USER_SHIFT			2
-#define PAGE_KERNEL_SHIFT		PAGE_USER_SHIFT
-#define PAGE_READ_SHIFT			3
 #define PAGE_WRITE_SHIFT		4
 #define PAGE_EXEC_SHIFT			5
 #define PAGE_GLOBAL_SHIFT		6
 
-#define PAGE_NOT_CACHEABLE		(0 << PAGE_CACHEABLE_SHIFT)
 #define PAGE_CACHEABLE			(1 << PAGE_CACHEABLE_SHIFT)
-
-#define PAGE_PRESENT			(0 << PAGE_PRESENT_SHIFT)
-#define PAGE_NOT_PRESENT		(1 << PAGE_PRESENT_SHIFT)
-
+#define PAGE_NOT_PRESENT		(1 << PAGE_NOT_PRESENT_SHIFT)
 #define PAGE_USER			(1 << PAGE_USER_SHIFT)
-#define PAGE_KERNEL			(0 << PAGE_USER_SHIFT)
-
-#define PAGE_READ			(1 << PAGE_READ_SHIFT)
 #define PAGE_WRITE			(1 << PAGE_WRITE_SHIFT)
 #define PAGE_EXEC			(1 << PAGE_EXEC_SHIFT)
-
 #define PAGE_GLOBAL			(1 << PAGE_GLOBAL_SHIFT)
 
Index: kernel/generic/include/mm/page.h
===================================================================
--- kernel/generic/include/mm/page.h	(revision 67f11a04d9b9007cff6be59c182bd35c4f3ee076)
+++ kernel/generic/include/mm/page.h	(revision 6be2c13c42be6b2f450ca654c0b1f32fb186f909)
@@ -49,5 +49,5 @@
 	void (*mapping_remove)(as_t *, uintptr_t);
 	bool (*mapping_find)(as_t *, uintptr_t, bool, pte_t *);
-	void (*mapping_update)(as_t *, uintptr_t, bool, pte_t *);
+	void (*mapping_update)(as_t *, uintptr_t, bool, const pte_t *);
 	void (*mapping_make_global)(uintptr_t, size_t);
 } page_mapping_operations_t;