1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2013-2015 Mellanox Technologies, Ltd. 5 * Copyright (c) 2014-2015 François Tigeot 6 * Copyright (c) 2016 Matt Macy <mmacy@FreeBSD.org> 7 * Copyright (c) 2019 Johannes Lundberg <johalun@FreeBSD.org> 8 * Copyright (c) 2023 Serenity Cyber Security, LLC. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #ifndef _LINUXKPI_LINUX_MATH_H_ 33 #define _LINUXKPI_LINUX_MATH_H_ 34 35 #include <linux/types.h> 36 37 /* 38 * This looks more complex than it should be. But we need to 39 * get the type for the ~ right in round_down (it needs to be 40 * as wide as the result!), and we want to evaluate the macro 41 * arguments just once each. 42 */ 43 #define __round_mask(x, y) ((__typeof__(x))((y)-1)) 44 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) 45 #define round_down(x, y) ((x) & ~__round_mask(x, y)) 46 47 #define DIV_ROUND_UP(x, n) howmany(x, n) 48 #define DIV_ROUND_UP_ULL(x, n) DIV_ROUND_UP((unsigned long long)(x), (n)) 49 #define DIV_ROUND_DOWN_ULL(x, n) (((unsigned long long)(x) / (n)) * (n)) 50 51 #define DIV_ROUND_CLOSEST(x, divisor) (((x) + ((divisor) / 2)) / (divisor)) 52 #define DIV_ROUND_CLOSEST_ULL(x, divisor) ({ \ 53 __typeof(divisor) __d = (divisor); \ 54 unsigned long long __ret = (x) + (__d) / 2; \ 55 __ret /= __d; \ 56 __ret; \ 57 }) 58 59 #if defined(LINUXKPI_VERSION) && LINUXKPI_VERSION >= 60600 60 #define abs_diff(x, y) ({ \ 61 __typeof(x) _x = (x); \ 62 __typeof(y) _y = (y); \ 63 _x > _y ? _x - _y : _y - _x; \ 64 }) 65 #endif 66 67 static inline uintmax_t 68 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor) 69 { 70 uintmax_t q = (x / divisor); 71 uintmax_t r = (x % divisor); 72 73 return ((q * multiplier) + ((r * multiplier) / divisor)); 74 } 75 76 #endif /* _LINUXKPI_LINUX_MATH_H_ */ 77