#define PFN_ALIGN(x) (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
#define PFN_UP(x) (((x) + PAGE_SIZE-1) >> PAGE_SHIFT)
#define PFN_DOWN(x) ((x) >> PAGE_SHIFT)
-#define PFN_PHYS(x) ((x) << PAGE_SHIFT)
+#define PFN_PHYS(x) ((unsigned long long)(x) << PAGE_SHIFT)
#endif