1 /* $NetBSD: kernel.h,v 1.45 2021/12/19 12:02:13 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 #include <asm/byteorder.h> 43 #include <asm/div64.h> 44 45 #include <linux/bitops.h> 46 #include <linux/compiler.h> 47 #include <linux/log2.h> 48 #include <linux/printk.h> 49 #include <linux/slab.h> 50 51 #define U16_MAX UINT16_MAX 52 #define U32_MAX UINT32_MAX 53 #define U64_MAX UINT64_MAX 54 55 #define S16_MAX INT16_MAX 56 #define S32_MAX INT32_MAX 57 #define S64_MAX INT64_MAX 58 59 #define oops_in_progress (panicstr != NULL) 60 61 #define IS_BUILTIN(option) (1) /* Probably... */ 62 #define IS_ENABLED(option) (option) 63 #define IS_REACHABLE(option) (option) 64 65 #define might_sleep ASSERT_SLEEPABLE 66 #define might_sleep_if(C) do \ 67 { \ 68 if (C) \ 69 might_sleep(); \ 70 } while (0) 71 72 #define DEFINE_STATIC_KEY_FALSE(N) bool N __unused = false 73 74 /* 75 * XXX Linux kludge to work around GCC uninitialized variable warning. 76 * Linux does `x = x', which is bollocks. 77 */ 78 #define uninitialized_var(x) x = 0 79 80 #define typecheck(T, X) ({(1 + 0*sizeof((T *)0 - &(X)));}) 81 82 /* XXX These will multiply evaluate their arguments. */ 83 #define min(X, Y) MIN(X, Y) 84 #define max(X, Y) MAX(X, Y) 85 86 #define max_t(T, X, Y) MAX((T)(X), (T)(Y)) 87 #define min_t(T, X, Y) MIN((T)(X), (T)(Y)) 88 89 #define clamp_t(T, X, MIN, MAX) min_t(T, max_t(T, X, MIN), MAX) 90 #define clamp(X, MN, MX) MIN(MAX(X, MN), MX) 91 #define clamp_val(X, MIN, MAX) clamp_t(typeof(X), X, MIN, MAX) 92 93 #define min3(X, Y, Z) MIN(X, MIN(Y, Z)) 94 #define max3(X, Y, Z) MAX(X, MAX(Y, Z)) 95 96 /* 97 * Rounding to nearest. 98 */ 99 #define DIV_ROUND_CLOSEST(N, D) \ 100 ((0 < (N)) ? (((N) + ((D) / 2)) / (D)) \ 101 : (((N) - ((D) / 2)) / (D))) 102 103 #define DIV_ROUND_CLOSEST_ULL(N, D) (((N) + (D)/2)/(D)) 104 105 /* 106 * Rounding to what may or may not be powers of two. 107 */ 108 #define DIV_ROUND_UP(X, N) (((X) + (N) - 1) / (N)) 109 #define DIV_ROUND_UP_ULL(X, N) DIV_ROUND_UP((unsigned long long)(X), (N)) 110 111 #define DIV_ROUND_DOWN_ULL(X,N) ((unsigned long long)(X) / (N)) 112 113 /* 114 * Rounding to powers of two -- carefully avoiding multiple evaluation 115 * of arguments and pitfalls with C integer arithmetic rules. 116 */ 117 #define round_up(X, N) ((((X) - 1) | ((N) - 1)) + 1) 118 #define round_down(X, N) ((X) & ~(uintmax_t)((N) - 1)) 119 120 #define IS_ALIGNED(X, N) (((X) & ((N) - 1)) == 0) 121 122 #define ALIGN_DOWN(X, N) round_down(X, N) 123 124 /* 125 * These select 32-bit halves of what may be 32- or 64-bit quantities, 126 * for which straight 32-bit shifts may be undefined behaviour (and do 127 * the wrong thing on most machines: return the input unshifted by 128 * ignoring the upper bits of the shift count). 129 */ 130 #define upper_32_bits(X) ((uint32_t) (((X) >> 16) >> 16)) 131 #define lower_32_bits(X) ((uint32_t) ((X) & 0xffffffffUL)) 132 133 #define ARRAY_SIZE(ARRAY) __arraycount(ARRAY) 134 135 #define __is_constexpr(x) __builtin_constant_p(x) 136 137 #define swap(X, Y) do \ 138 { \ 139 /* XXX Kludge for type-safety. */ \ 140 if (&(X) != &(Y)) { \ 141 CTASSERT(sizeof(X) == sizeof(Y)); \ 142 /* XXX Can't do this much better without typeof. */ \ 143 char __swap_tmp[sizeof(X)]; \ 144 (void)memcpy(__swap_tmp, &(X), sizeof(X)); \ 145 (void)memcpy(&(X), &(Y), sizeof(X)); \ 146 (void)memcpy(&(Y), __swap_tmp, sizeof(X)); \ 147 } \ 148 } while (0) 149 150 static __inline int64_t 151 abs64(int64_t x) 152 { 153 return (x < 0? (-x) : x); 154 } 155 156 static __inline uintmax_t 157 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor) 158 { 159 uintmax_t q = (x / divisor); 160 uintmax_t r = (x % divisor); 161 162 return ((q * multiplier) + ((r * multiplier) / divisor)); 163 } 164 165 static int panic_timeout __unused = 0; 166 167 static __inline int __printflike(3, 0) 168 vscnprintf(char *buf, size_t size, const char *fmt, va_list va) 169 { 170 int ret; 171 172 ret = vsnprintf(buf, size, fmt, va); 173 if (__predict_false(ret < 0)) 174 return ret; 175 if (__predict_false(size == 0)) 176 return 0; 177 if (__predict_false(size <= (size_t)ret)) 178 return (size - 1); 179 180 return ret; 181 } 182 183 static __inline int __printflike(3, 4) 184 scnprintf(char *buf, size_t size, const char *fmt, ...) 185 { 186 va_list va; 187 int ret; 188 189 va_start(va, fmt); 190 ret = vscnprintf(buf, size, fmt, va); 191 va_end(va); 192 193 return ret; 194 } 195 196 static __inline int 197 kstrtol(const char *s, unsigned base, long *vp) 198 { 199 long long v; 200 201 v = strtoll(s, NULL, base); 202 if (v < LONG_MIN || LONG_MAX < v) 203 return -ERANGE; 204 *vp = v; 205 return 0; 206 } 207 208 static inline long 209 simple_strtol(const char *s, char **endp, unsigned base) 210 { 211 long v; 212 213 *endp = NULL; /* paranoia */ 214 v = strtoll(s, endp, base); 215 if (v < LONG_MIN || LONG_MAX < v) 216 return 0; 217 return v; 218 } 219 220 static __inline char * __printflike(2, 0) 221 kvasprintf(gfp_t gfp, const char *fmt, va_list va) 222 { 223 va_list tva; 224 char *str; 225 int len, len1 __diagused; 226 227 va_copy(tva, va); 228 len = vsnprintf(NULL, 0, fmt, tva); 229 va_end(tva); 230 str = kmalloc(len + 1, gfp); 231 if (str == NULL) 232 return NULL; 233 len1 = vsnprintf(str, len + 1, fmt, va); 234 KASSERT(len1 == len); 235 236 return str; 237 } 238 239 static __inline char * __printflike(2, 3) 240 kasprintf(gfp_t gfp, const char *fmt, ...) 241 { 242 va_list va; 243 char *str; 244 245 va_start(va, fmt); 246 str = kvasprintf(gfp, fmt, va); 247 va_end(va); 248 249 return str; 250 } 251 252 static inline void __user * 253 u64_to_user_ptr(uint64_t addr) 254 { 255 256 return (void __user *)(uintptr_t)addr; 257 } 258 259 #define TAINT_MACHINE_CHECK 0 260 #define TAINT_WARN 1 261 262 #define LOCKDEP_STILL_OK 0 263 264 static inline void 265 add_taint(unsigned taint, int lockdep) 266 { 267 } 268 269 #define DFEINE_STATIC_KEY_FALSE(FLAG) \ 270 bool FLAG = false 271 272 static inline bool 273 static_branch_likely(const bool *flagp) 274 { 275 return __predict_true(*flagp); 276 } 277 278 static inline int 279 sscanf(const char *fmt, ...) 280 { 281 return 0; /* XXX */ 282 } 283 284 #endif /* _LINUX_KERNEL_H_ */ 285