1 /* $NetBSD: kernel.h,v 1.9 2018/08/06 00:30:33 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _LINUX_KERNEL_H_ 33 #define _LINUX_KERNEL_H_ 34 35 #include <sys/cdefs.h> 36 #include <sys/types.h> 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 40 #include <lib/libkern/libkern.h> 41 42 #define oops_in_progress (panicstr != NULL) 43 44 #define IS_ENABLED(option) (option) 45 46 #define __printf __printflike 47 #define __user 48 #define __must_check /* __attribute__((warn_unused_result)), if GCC */ 49 #define __always_unused __unused 50 51 #define barrier() __insn_barrier() 52 #define likely(X) __predict_true(X) 53 #define unlikely(X) __predict_false(X) 54 55 /* 56 * XXX Linux kludge to work around GCC uninitialized variable warning. 57 * Linux does `x = x', which is bollocks. 58 */ 59 #define uninitialized_var(x) x = 0 60 61 /* XXX These will multiply evaluate their arguments. */ 62 #define min(X, Y) MIN(X, Y) 63 #define max(X, Y) MAX(X, Y) 64 65 #define max_t(T, X, Y) MAX(X, Y) 66 #define min_t(T, X, Y) MIN(X, Y) 67 68 #define clamp_t(T, X, MIN, MAX) min_t(T, max_t(T, X, MIN), MAX) 69 #define clamp(X, MN, MX) MIN(MAX(X, MN), MX) 70 71 /* 72 * Rounding to nearest. 73 */ 74 #define DIV_ROUND_CLOSEST(N, D) \ 75 ((0 < (N)) ? (((N) + ((D) / 2)) / (D)) \ 76 : (((N) - ((D) / 2)) / (D))) 77 78 /* 79 * Rounding to what may or may not be powers of two. 80 */ 81 #define DIV_ROUND_UP(X, N) (((X) + (N) - 1) / (N)) 82 #define DIV_ROUND_UP_ULL(X, N) DIV_ROUND_UP((unsigned long long)(X), (N)) 83 84 /* 85 * Rounding to powers of two -- carefully avoiding multiple evaluation 86 * of arguments and pitfalls with C integer arithmetic rules. 87 */ 88 #define round_up(X, N) ((((X) - 1) | ((N) - 1)) + 1) 89 #define round_down(X, N) ((X) & ~(uintmax_t)((N) - 1)) 90 91 #define IS_ALIGNED(X, N) (((X) & ((N) - 1)) == 0) 92 93 /* 94 * These select 32-bit halves of what may be 32- or 64-bit quantities, 95 * for which straight 32-bit shifts may be undefined behaviour (and do 96 * the wrong thing on most machines: return the input unshifted by 97 * ignoring the upper bits of the shift count). 98 */ 99 #define upper_32_bits(X) ((uint32_t) (((X) >> 16) >> 16)) 100 #define lower_32_bits(X) ((uint32_t) ((X) & 0xffffffffUL)) 101 102 #define ARRAY_SIZE(ARRAY) __arraycount(ARRAY) 103 104 #define swap(X, Y) do \ 105 { \ 106 /* XXX Kludge for type-safety. */ \ 107 if (&(X) != &(Y)) { \ 108 CTASSERT(sizeof(X) == sizeof(Y)); \ 109 /* XXX Can't do this much better without typeof. */ \ 110 char __swap_tmp[sizeof(X)]; \ 111 (void)memcpy(__swap_tmp, &(X), sizeof(X)); \ 112 (void)memcpy(&(X), &(Y), sizeof(X)); \ 113 (void)memcpy(&(Y), __swap_tmp, sizeof(X)); \ 114 } \ 115 } while (0) 116 117 static inline int64_t 118 abs64(int64_t x) 119 { 120 return (x < 0? (-x) : x); 121 } 122 123 static inline uintmax_t 124 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor) 125 { 126 uintmax_t q = (x / divisor); 127 uintmax_t r = (x % divisor); 128 129 return ((q * multiplier) + ((r * multiplier) / divisor)); 130 } 131 132 static int panic_timeout __unused = 0; 133 134 static inline int 135 vscnprintf(char *buf, size_t size, const char *fmt, va_list va) 136 { 137 int ret; 138 139 ret = vsnprintf(buf, size, fmt, va); 140 if (__predict_false(ret < 0)) 141 return ret; 142 if (__predict_false(size == 0)) 143 return 0; 144 if (__predict_false(size <= ret)) 145 return (size - 1); 146 147 return ret; 148 } 149 150 static inline int 151 scnprintf(char *buf, size_t size, const char *fmt, ...) 152 { 153 va_list va; 154 int ret; 155 156 va_start(va, fmt); 157 ret = vscnprintf(buf, size, fmt, va); 158 va_end(va); 159 160 return ret; 161 } 162 163 static inline int 164 kstrtol(const char *s, unsigned base, long *vp) 165 { 166 long long v; 167 168 v = strtoll(s, NULL, base); 169 if (v < LONG_MIN || LONG_MAX < v) 170 return -ERANGE; 171 *vp = v; 172 return 0; 173 } 174 175 #endif /* _LINUX_KERNEL_H_ */ 176