#ifndef _TOOLS_MATH_H#define _TOOLS_MATH_H /* * This looks more complex than it should be. But we need to * get the type for the ~ right in round_down (it needs to be * as wide as the result!), and we want to evaluate the macro * arguments just once each. */#define __round_mask(x, y) ((__typeof__(x))((y)-1))#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)#define round_down(x, y) ((x) & ~__round_mask(x, y)) #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d)) #ifndef roundup#define roundup(x, y) (                                \{                                                      \	const typeof(y) __y = y;		       \	(((x) + (__y - 1)) / __y) * __y;	       \}                                                      \)#endif #endif