xref: /freebsd/sys/compat/linuxkpi/common/include/linux/math64.h (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * Copyright (c) 2007 Cisco Systems, Inc.  All rights reserved.
3  * Copyright (c) 2014-2015 Mellanox Technologies, Ltd. All rights reserved.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice unmodified, this list of conditions, and the following
11  *    disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #ifndef _LINUXKPI_LINUX_MATH64_H
31 #define	_LINUXKPI_LINUX_MATH64_H
32 
33 #include <sys/stdint.h>
34 
35 #define	do_div(n, base) ({			\
36 	uint32_t __base = (base);		\
37 	uint32_t __rem;				\
38 	__rem = ((uint64_t)(n)) % __base;	\
39 	(n) = ((uint64_t)(n)) / __base;		\
40 	__rem;					\
41 })
42 
43 static inline uint64_t
44 div64_u64_rem(uint64_t dividend, uint64_t divisor, uint64_t *remainder)
45 {
46 
47 	*remainder = dividend % divisor;
48 	return (dividend / divisor);
49 }
50 
51 static inline int64_t
52 div64_s64(int64_t dividend, int64_t divisor)
53 {
54 
55 	return (dividend / divisor);
56 }
57 
58 static inline uint64_t
59 div64_u64(uint64_t dividend, uint64_t divisor)
60 {
61 
62 	return (dividend / divisor);
63 }
64 
65 static inline uint64_t
66 div_u64_rem(uint64_t dividend, uint32_t divisor, uint32_t *remainder)
67 {
68 
69 	*remainder = dividend % divisor;
70 	return (dividend / divisor);
71 }
72 
73 static inline int64_t
74 div_s64(int64_t dividend, int32_t divisor)
75 {
76 
77 	return (dividend / divisor);
78 }
79 
80 static inline uint64_t
81 div_u64(uint64_t dividend, uint32_t divisor)
82 {
83 
84 	return (dividend / divisor);
85 }
86 
87 static inline uint64_t
88 mul_u32_u32(uint32_t a, uint32_t b)
89 {
90 
91 	return ((uint64_t)a * b);
92 }
93 
94 static inline uint64_t
95 div64_u64_round_up(uint64_t dividend, uint64_t divisor)
96 {
97 	return ((dividend + divisor - 1) / divisor);
98 }
99 
100 #define	DIV64_U64_ROUND_UP(...) \
101 	div64_u64_round_up(__VA_ARGS__)
102 
103 static inline uint64_t
104 mul_u64_u32_div(uint64_t x, uint32_t y, uint32_t div)
105 {
106 	const uint64_t rem = x % div;
107 
108 	return ((x / div) * y + (rem * y) / div);
109 }
110 
111 static inline uint64_t
112 mul_u64_u32_shr(uint64_t x, uint32_t y, unsigned int shift)
113 {
114 	uint32_t hi, lo;
115 	hi = x >> 32;
116 	lo = x & 0xffffffff;
117 
118 	return (mul_u32_u32(lo, y) >> shift) +
119 		(mul_u32_u32(hi, y) << (32 - shift));
120 }
121 
122 #endif /* _LINUXKPI_LINUX_MATH64_H */
123