kernel.h revision 1.28
1 /* $NetBSD: kernel.h,v 1.28 2021/12/19 00:47:47 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 #include <sys/endian.h> 40 41 #include <lib/libkern/libkern.h> 42 43 #include <asm/byteorder.h> 44 #include <asm/div64.h> 45 46 #include <linux/bitops.h> 47 #include <linux/compiler.h> 48 #include <linux/log2.h> 49 #include <linux/printk.h> 50 #include <linux/slab.h> 51 52 #define U16_MAX UINT16_MAX 53 #define U32_MAX UINT32_MAX 54 #define U64_MAX UINT64_MAX 55 56 #define oops_in_progress (panicstr != NULL) 57 58 #if BYTE_ORDER == BIG_ENDIAN 59 #define __BIG_ENDIAN _BIG_ENDIAN 60 #else 61 #define __LITTLE_ENDIAN _LITTLE_ENDIAN 62 #endif 63 64 #define IS_BUILTIN(option) (1) /* Probably... */ 65 #define IS_ENABLED(option) (option) 66 #define IS_REACHABLE(option) (option) 67 68 #define __printf __printflike 69 #define __user 70 #if __GNUC_PREREQ__(4,0) /* not sure when but this will work */ 71 #define __must_check __attribute__((warn_unused_result)) 72 #else 73 #define __must_check /* nothing */ 74 #endif 75 #define __always_unused __unused 76 #define noinline __noinline 77 78 #define barrier() __insn_barrier() 79 #define likely(X) __predict_true(X) 80 #define unlikely(X) __predict_false(X) 81 82 /* 83 * XXX Linux kludge to work around GCC uninitialized variable warning. 84 * Linux does `x = x', which is bollocks. 85 */ 86 #define uninitialized_var(x) x = 0 87 88 /* XXX These will multiply evaluate their arguments. */ 89 #define min(X, Y) MIN(X, Y) 90 #define max(X, Y) MAX(X, Y) 91 92 #define max_t(T, X, Y) MAX(X, Y) 93 #define min_t(T, X, Y) MIN(X, Y) 94 95 #define clamp_t(T, X, MIN, MAX) min_t(T, max_t(T, X, MIN), MAX) 96 #define clamp(X, MN, MX) MIN(MAX(X, MN), MX) 97 98 #define min3(X, Y, Z) MIN(X, MIN(Y, Z)) 99 #define max3(X, Y, Z) MAX(X, MAX(Y, Z)) 100 101 /* 102 * Rounding to nearest. 103 */ 104 #define DIV_ROUND_CLOSEST(N, D) \ 105 ((0 < (N)) ? (((N) + ((D) / 2)) / (D)) \ 106 : (((N) - ((D) / 2)) / (D))) 107 108 #define DIV_ROUND_CLOSEST_ULL(N, D) (((N) + (D)/2)/(D)) 109 110 /* 111 * Rounding to what may or may not be powers of two. 112 */ 113 #define DIV_ROUND_UP(X, N) (((X) + (N) - 1) / (N)) 114 #define DIV_ROUND_UP_ULL(X, N) DIV_ROUND_UP((unsigned long long)(X), (N)) 115 116 /* 117 * Rounding to powers of two -- carefully avoiding multiple evaluation 118 * of arguments and pitfalls with C integer arithmetic rules. 119 */ 120 #define round_up(X, N) ((((X) - 1) | ((N) - 1)) + 1) 121 #define round_down(X, N) ((X) & ~(uintmax_t)((N) - 1)) 122 123 #define IS_ALIGNED(X, N) (((X) & ((N) - 1)) == 0) 124 125 /* 126 * These select 32-bit halves of what may be 32- or 64-bit quantities, 127 * for which straight 32-bit shifts may be undefined behaviour (and do 128 * the wrong thing on most machines: return the input unshifted by 129 * ignoring the upper bits of the shift count). 130 */ 131 #define upper_32_bits(X) ((uint32_t) (((X) >> 16) >> 16)) 132 #define lower_32_bits(X) ((uint32_t) ((X) & 0xffffffffUL)) 133 134 #define ARRAY_SIZE(ARRAY) __arraycount(ARRAY) 135 136 #define swap(X, Y) do \ 137 { \ 138 /* XXX Kludge for type-safety. */ \ 139 if (&(X) != &(Y)) { \ 140 CTASSERT(sizeof(X) == sizeof(Y)); \ 141 /* XXX Can't do this much better without typeof. */ \ 142 char __swap_tmp[sizeof(X)]; \ 143 (void)memcpy(__swap_tmp, &(X), sizeof(X)); \ 144 (void)memcpy(&(X), &(Y), sizeof(X)); \ 145 (void)memcpy(&(Y), __swap_tmp, sizeof(X)); \ 146 } \ 147 } while (0) 148 149 #define ACCESS_ONCE(X) ({ \ 150 typeof(X) __access_once_tmp = (X); \ 151 __insn_barrier(); \ 152 __access_once_tmp; \ 153 }) 154 155 static __inline int64_t 156 abs64(int64_t x) 157 { 158 return (x < 0? (-x) : x); 159 } 160 161 static __inline uintmax_t 162 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor) 163 { 164 uintmax_t q = (x / divisor); 165 uintmax_t r = (x % divisor); 166 167 return ((q * multiplier) + ((r * multiplier) / divisor)); 168 } 169 170 static int panic_timeout __unused = 0; 171 172 static __inline int __printflike(3, 0) 173 vscnprintf(char *buf, size_t size, const char *fmt, va_list va) 174 { 175 int ret; 176 177 ret = vsnprintf(buf, size, fmt, va); 178 if (__predict_false(ret < 0)) 179 return ret; 180 if (__predict_false(size == 0)) 181 return 0; 182 if (__predict_false(size <= (size_t)ret)) 183 return (size - 1); 184 185 return ret; 186 } 187 188 static __inline int __printflike(3, 4) 189 scnprintf(char *buf, size_t size, const char *fmt, ...) 190 { 191 va_list va; 192 int ret; 193 194 va_start(va, fmt); 195 ret = vscnprintf(buf, size, fmt, va); 196 va_end(va); 197 198 return ret; 199 } 200 201 static __inline int 202 kstrtol(const char *s, unsigned base, long *vp) 203 { 204 long long v; 205 206 v = strtoll(s, NULL, base); 207 if (v < LONG_MIN || LONG_MAX < v) 208 return -ERANGE; 209 *vp = v; 210 return 0; 211 } 212 213 static inline long 214 simple_strtol(const char *s, char **endp, unsigned base) 215 { 216 long v; 217 218 *endp = NULL; /* paranoia */ 219 v = strtoll(s, endp, base); 220 if (v < LONG_MIN || LONG_MAX < v) 221 return 0; 222 return v; 223 } 224 225 static __inline char * __printflike(2, 0) 226 kvasprintf(gfp_t gfp, const char *fmt, va_list va) 227 { 228 va_list tva; 229 char *str; 230 int len, len1 __diagused; 231 232 va_copy(tva, va); 233 len = vsnprintf(NULL, 0, fmt, tva); 234 va_end(tva); 235 str = kmalloc(len + 1, gfp); 236 if (str == NULL) 237 return NULL; 238 len1 = vsnprintf(str, len + 1, fmt, va); 239 KASSERT(len1 == len); 240 241 return str; 242 } 243 244 static __inline char * __printflike(2, 3) 245 kasprintf(gfp_t gfp, const char *fmt, ...) 246 { 247 va_list va; 248 char *str; 249 250 va_start(va, fmt); 251 str = kvasprintf(gfp, fmt, va); 252 va_end(va); 253 254 return str; 255 } 256 257 #endif /* _LINUX_KERNEL_H_ */ 258
Indexes created Sun Sep 21 20:09:37 GMT 2025