-#define PAGE_SIZE sysconf(_SC_PAGE_SIZE)
-#define PAGE_MASK (~(PAGE_SIZE - 1))
-#define __ALIGN_MASK(v, mask) (((v) + (mask)) & ~(mask))
-#define ALIGN(v, align) __ALIGN_MASK(v, (typeof(v)) (align) - 1)
-#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)