| 1 | /* $NetBSD: kernel.h,v 1.8 2015/08/20 21:41:12 skrll 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 max_t(T, X, Y) MAX(X, Y) |
| 63 | #define min_t(T, X, Y) MIN(X, Y) |
| 64 | |
| 65 | #define clamp_t(T, X, MIN, MAX) min_t(T, max_t(T, X, MIN), MAX) |
| 66 | #define clamp(X, MN, MX) MIN(MAX(X, MN), MX) |
| 67 | |
| 68 | /* |
| 69 | * Rounding to nearest. |
| 70 | */ |
| 71 | #define DIV_ROUND_CLOSEST(N, D) \ |
| 72 | ((0 < (N)) ? (((N) + ((D) / 2)) / (D)) \ |
| 73 | : (((N) - ((D) / 2)) / (D))) |
| 74 | |
| 75 | /* |
| 76 | * Rounding to what may or may not be powers of two. |
| 77 | */ |
| 78 | #define DIV_ROUND_UP(X, N) (((X) + (N) - 1) / (N)) |
| 79 | #define DIV_ROUND_UP_ULL(X, N) DIV_ROUND_UP((unsigned long long)(X), (N)) |
| 80 | |
| 81 | /* |
| 82 | * Rounding to powers of two -- carefully avoiding multiple evaluation |
| 83 | * of arguments and pitfalls with C integer arithmetic rules. |
| 84 | */ |
| 85 | #define round_up(X, N) ((((X) - 1) | ((N) - 1)) + 1) |
| 86 | #define round_down(X, N) ((X) & ~(uintmax_t)((N) - 1)) |
| 87 | |
| 88 | #define IS_ALIGNED(X, N) (((X) & ((N) - 1)) == 0) |
| 89 | |
| 90 | /* |
| 91 | * These select 32-bit halves of what may be 32- or 64-bit quantities, |
| 92 | * for which straight 32-bit shifts may be undefined behaviour (and do |
| 93 | * the wrong thing on most machines: return the input unshifted by |
| 94 | * ignoring the upper bits of the shift count). |
| 95 | */ |
| 96 | #define upper_32_bits(X) ((uint32_t) (((X) >> 16) >> 16)) |
| 97 | #define lower_32_bits(X) ((uint32_t) ((X) & 0xffffffffUL)) |
| 98 | |
| 99 | #define ARRAY_SIZE(ARRAY) __arraycount(ARRAY) |
| 100 | |
| 101 | #define swap(X, Y) do \ |
| 102 | { \ |
| 103 | /* XXX Kludge for type-safety. */ \ |
| 104 | if (&(X) != &(Y)) { \ |
| 105 | CTASSERT(sizeof(X) == sizeof(Y)); \ |
| 106 | /* XXX Can't do this much better without typeof. */ \ |
| 107 | char __swap_tmp[sizeof(X)]; \ |
| 108 | (void)memcpy(__swap_tmp, &(X), sizeof(X)); \ |
| 109 | (void)memcpy(&(X), &(Y), sizeof(X)); \ |
| 110 | (void)memcpy(&(Y), __swap_tmp, sizeof(X)); \ |
| 111 | } \ |
| 112 | } while (0) |
| 113 | |
| 114 | static inline int64_t |
| 115 | abs64(int64_t x) |
| 116 | { |
| 117 | return (x < 0? (-x) : x); |
| 118 | } |
| 119 | |
| 120 | static inline uintmax_t |
| 121 | mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor) |
| 122 | { |
| 123 | uintmax_t q = (x / divisor); |
| 124 | uintmax_t r = (x % divisor); |
| 125 | |
| 126 | return ((q * multiplier) + ((r * multiplier) / divisor)); |
| 127 | } |
| 128 | |
| 129 | static int panic_timeout __unused = 0; |
| 130 | |
| 131 | static inline int |
| 132 | vscnprintf(char *buf, size_t size, const char *fmt, va_list va) |
| 133 | { |
| 134 | int ret; |
| 135 | |
| 136 | ret = vsnprintf(buf, size, fmt, va); |
| 137 | if (__predict_false(ret < 0)) |
| 138 | return ret; |
| 139 | if (__predict_false(size == 0)) |
| 140 | return 0; |
| 141 | if (__predict_false(size <= ret)) |
| 142 | return (size - 1); |
| 143 | |
| 144 | return ret; |
| 145 | } |
| 146 | |
| 147 | static inline int |
| 148 | scnprintf(char *buf, size_t size, const char *fmt, ...) |
| 149 | { |
| 150 | va_list va; |
| 151 | int ret; |
| 152 | |
| 153 | va_start(va, fmt); |
| 154 | ret = vscnprintf(buf, size, fmt, va); |
| 155 | va_end(va); |
| 156 | |
| 157 | return ret; |
| 158 | } |
| 159 | |
| 160 | static inline int |
| 161 | kstrtol(const char *s, unsigned base, long *vp) |
| 162 | { |
| 163 | long long v; |
| 164 | |
| 165 | v = strtoll(s, NULL, base); |
| 166 | if (v < LONG_MIN || LONG_MAX < v) |
| 167 | return -ERANGE; |
| 168 | *vp = v; |
| 169 | return 0; |
| 170 | } |
| 171 | |
| 172 | #endif /* _LINUX_KERNEL_H_ */ |
| 173 | |