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 28 #ifndef _LINUXKPI_LINUX_MATH64_H 29 #define _LINUXKPI_LINUX_MATH64_H 30 31 #include <sys/stdint.h> 32 #include <sys/systm.h> 33 34 #define do_div(n, base) ({ \ 35 uint32_t __base = (base); \ 36 uint32_t __rem; \ 37 __rem = ((uint64_t)(n)) % __base; \ 38 (n) = ((uint64_t)(n)) / __base; \ 39 __rem; \ 40 }) 41 42 static inline uint64_t 43 div64_u64_rem(uint64_t dividend, uint64_t divisor, uint64_t *remainder) 44 { 45 46 *remainder = dividend % divisor; 47 return (dividend / divisor); 48 } 49 50 static inline int64_t 51 div64_s64(int64_t dividend, int64_t divisor) 52 { 53 54 return (dividend / divisor); 55 } 56 57 static inline uint64_t 58 div64_u64(uint64_t dividend, uint64_t divisor) 59 { 60 61 return (dividend / divisor); 62 } 63 64 #define div64_ul(x, y) div64_u64((x), (y)) 65 66 static inline uint64_t 67 div_u64_rem(uint64_t dividend, uint32_t divisor, uint32_t *remainder) 68 { 69 70 *remainder = dividend % divisor; 71 return (dividend / divisor); 72 } 73 74 static inline int64_t 75 div_s64(int64_t dividend, int32_t divisor) 76 { 77 78 return (dividend / divisor); 79 } 80 81 static inline uint64_t 82 div_u64(uint64_t dividend, uint32_t divisor) 83 { 84 85 return (dividend / divisor); 86 } 87 88 static inline uint64_t 89 mul_u32_u32(uint32_t a, uint32_t b) 90 { 91 92 return ((uint64_t)a * b); 93 } 94 95 static inline uint64_t 96 div_u64_round_up(uint64_t dividend, uint32_t divisor) 97 { 98 return ((dividend + divisor - 1) / divisor); 99 } 100 101 static inline uint64_t 102 div64_u64_round_up(uint64_t dividend, uint64_t divisor) 103 { 104 return ((dividend + divisor - 1) / divisor); 105 } 106 107 static inline uint64_t 108 roundup_u64(uint64_t x1, uint32_t x2) 109 { 110 return (div_u64(x1 + x2 - 1, x2) * x2); 111 } 112 113 #define DIV_U64_ROUND_UP(...) \ 114 div_u64_round_up(__VA_ARGS__) 115 116 #define DIV64_U64_ROUND_UP(...) \ 117 div64_u64_round_up(__VA_ARGS__) 118 119 static inline uint64_t 120 mul_u64_u32_div(uint64_t x, uint32_t y, uint32_t div) 121 { 122 const uint64_t rem = x % div; 123 124 return ((x / div) * y + (rem * y) / div); 125 } 126 127 static inline uint64_t 128 mul_u64_u64_div_u64(uint64_t x, uint64_t y, uint64_t z) 129 { 130 uint64_t res, rem; 131 uint64_t x1, y1, y1z; 132 133 res = rem = 0; 134 x1 = x; 135 y1z = y / z; 136 y1 = y - y1z * z; 137 138 /* 139 * INVARIANT: x * y = res * z + rem + (y1 + y1z * z) * x1 140 * INVARIANT: y1 < z 141 * INVARIANT: rem < z 142 */ 143 while (x1 > 0) { 144 /* Handle low bit. */ 145 if (x1 & 1) { 146 x1 &= ~1; 147 res += y1z; 148 rem += y1; 149 if ((rem < y1) || (rem >= z)) { 150 res += 1; 151 rem -= z; 152 } 153 } 154 155 /* Shift x1 right and (y1 + y1z * z) left */ 156 x1 >>= 1; 157 if ((y1 * 2 < y1) || (y1 * 2 >= z)) { 158 y1z = y1z * 2 + 1; 159 y1 = y1 * 2 - z; 160 } else { 161 y1z *= 2; 162 y1 *= 2; 163 } 164 } 165 166 KASSERT(res * z + rem == x * y, ("%s: res %ju * z %ju + rem %ju != " 167 "x %ju * y %ju", __func__, (uintmax_t)res, (uintmax_t)z, 168 (uintmax_t)rem, (uintmax_t)x, (uintmax_t)y)); 169 KASSERT(rem < z, ("%s: rem %ju >= z %ju\n", __func__, 170 (uintmax_t)rem, (uintmax_t)z)); 171 172 return (res); 173 } 174 175 static inline uint64_t 176 mul_u64_u32_shr(uint64_t x, uint32_t y, unsigned int shift) 177 { 178 uint32_t hi, lo; 179 hi = x >> 32; 180 lo = x & 0xffffffff; 181 182 return (mul_u32_u32(lo, y) >> shift) + 183 (mul_u32_u32(hi, y) << (32 - shift)); 184 } 185 186 #endif /* _LINUXKPI_LINUX_MATH64_H */ 187