SWP_TYPE_SHIFT 13 include/linux/swapops.h #define SWP_OFFSET_MASK(e) ((1UL << SWP_TYPE_SHIFT(e)) - 1) SWP_TYPE_SHIFT 22 include/linux/swapops.h ret.val = (type << SWP_TYPE_SHIFT(ret)) | SWP_TYPE_SHIFT 33 include/linux/swapops.h return (entry.val >> SWP_TYPE_SHIFT(entry));