Update freelist

kern/libkern/freelist.h

@@ -5,18 +5,24 @@
 #include <stdint.h>
 #include <stdlib.h>
 
-#define FL_FREE ((uint8_t)0x00)
-#define FL_USED ((uint8_t)0x01)
+/* Align to nearest multiple of align */
+static inline size_t align_up_to(size_t n, size_t align) {
+    return (n + align - 1) & ~(align - 1);
+}
 
-typedef struct FreeListBlock {
-    struct FreeListBlock *next;
-    uint8_t               block_state;
-} FreeListBlock;
+/* Fiddle these around according to your need. Delete or check makefile */
+#ifdef FREELIST_ALIGN
+#define ALIGN(x) (align_up_to(x, sizeof(void *)))
+#else
+#define ALIGN(x) (x)
+#endif
+
+typedef struct FreeListBlock FreeListBlock;
 
 typedef struct {
+    FreeListBlock *free;
     uintptr_t      start;
     uintptr_t      end;
-    FreeListBlock *free;
     size_t         size;
     size_t         allocated;
 } FreeList;