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
mult_frac(uintmax_t x,uintmax_t multiplier,uintmax_t divisor)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