1 /* $NetBSD: kernel.h,v 1.46 2022/10/25 23:37:36 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 S16_MIN INT16_MIN
57 #define S32_MAX INT32_MAX
58 #define S32_MIN INT32_MIN
59 #define S64_MAX INT64_MAX
60 #define S64_MIN INT64_MIN
61
62 #define oops_in_progress (panicstr != NULL)
63
64 #define IS_BUILTIN(option) (1) /* Probably... */
65 #define IS_ENABLED(option) (option)
66 #define IS_REACHABLE(option) (option)
67
68 #define might_sleep ASSERT_SLEEPABLE
69 #define might_sleep_if(C) do \
70 { \
71 if (C) \
72 might_sleep(); \
73 } while (0)
74
75 #define DEFINE_STATIC_KEY_FALSE(N) bool N __unused = false
76
77 /*
78 * XXX Linux kludge to work around GCC uninitialized variable warning.
79 * Linux does `x = x', which is bollocks.
80 */
81 #define uninitialized_var(x) x = 0
82
83 #define typecheck(T, X) ({(1 + 0*sizeof((T *)0 - &(X)));})
84
85 /* XXX These will multiply evaluate their arguments. */
86 #define min(X, Y) MIN(X, Y)
87 #define max(X, Y) MAX(X, Y)
88
89 #define max_t(T, X, Y) MAX((T)(X), (T)(Y))
90 #define min_t(T, X, Y) MIN((T)(X), (T)(Y))
91
92 #define clamp_t(T, X, MIN, MAX) min_t(T, max_t(T, X, MIN), MAX)
93 #define clamp(X, MN, MX) MIN(MAX(X, MN), MX)
94 #define clamp_val(X, MIN, MAX) clamp_t(typeof(X), X, MIN, MAX)
95
96 #define min3(X, Y, Z) MIN(X, MIN(Y, Z))
97 #define max3(X, Y, Z) MAX(X, MAX(Y, Z))
98
99 /*
100 * Rounding to nearest.
101 */
102 #define DIV_ROUND_CLOSEST(N, D) \
103 ((0 < (N)) ? (((N) + ((D) / 2)) / (D)) \
104 : (((N) - ((D) / 2)) / (D)))
105
106 #define DIV_ROUND_CLOSEST_ULL(N, D) (((N) + (D)/2)/(D))
107
108 /*
109 * Rounding to what may or may not be powers of two.
110 */
111 #define DIV_ROUND_UP(X, N) (((X) + (N) - 1) / (N))
112 #define DIV_ROUND_UP_ULL(X, N) DIV_ROUND_UP((unsigned long long)(X), (N))
113
114 #define DIV_ROUND_DOWN_ULL(X,N) ((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 #define ALIGN_DOWN(X, N) round_down(X, N)
126
127 /*
128 * These select 32-bit halves of what may be 32- or 64-bit quantities,
129 * for which straight 32-bit shifts may be undefined behaviour (and do
130 * the wrong thing on most machines: return the input unshifted by
131 * ignoring the upper bits of the shift count).
132 */
133 #define upper_32_bits(X) ((uint32_t) (((X) >> 16) >> 16))
134 #define lower_32_bits(X) ((uint32_t) ((X) & 0xffffffffUL))
135
136 #define ARRAY_SIZE(ARRAY) __arraycount(ARRAY)
137
138 #define __is_constexpr(x) __builtin_constant_p(x)
139
140 #define swap(X, Y) do \
141 { \
142 /* XXX Kludge for type-safety. */ \
143 if (&(X) != &(Y)) { \
144 CTASSERT(sizeof(X) == sizeof(Y)); \
145 /* XXX Can't do this much better without typeof. */ \
146 char __swap_tmp[sizeof(X)]; \
147 (void)memcpy(__swap_tmp, &(X), sizeof(X)); \
148 (void)memcpy(&(X), &(Y), sizeof(X)); \
149 (void)memcpy(&(Y), __swap_tmp, sizeof(X)); \
150 } \
151 } while (0)
152
153 static __inline int64_t
abs64(int64_t x)154 abs64(int64_t x)
155 {
156 return (x < 0? (-x) : x);
157 }
158
159 static __inline uintmax_t
mult_frac(uintmax_t x,uintmax_t multiplier,uintmax_t divisor)160 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor)
161 {
162 uintmax_t q = (x / divisor);
163 uintmax_t r = (x % divisor);
164
165 return ((q * multiplier) + ((r * multiplier) / divisor));
166 }
167
168 static int panic_timeout __unused = 0;
169
170 static __inline int __printflike(3, 0)
vscnprintf(char * buf,size_t size,const char * fmt,va_list va)171 vscnprintf(char *buf, size_t size, const char *fmt, va_list va)
172 {
173 int ret;
174
175 ret = vsnprintf(buf, size, fmt, va);
176 if (__predict_false(ret < 0))
177 return ret;
178 if (__predict_false(size == 0))
179 return 0;
180 if (__predict_false(size <= (size_t)ret))
181 return (size - 1);
182
183 return ret;
184 }
185
186 static __inline int __printflike(3, 4)
scnprintf(char * buf,size_t size,const char * fmt,...)187 scnprintf(char *buf, size_t size, const char *fmt, ...)
188 {
189 va_list va;
190 int ret;
191
192 va_start(va, fmt);
193 ret = vscnprintf(buf, size, fmt, va);
194 va_end(va);
195
196 return ret;
197 }
198
199 static __inline int
kstrtol(const char * s,unsigned base,long * vp)200 kstrtol(const char *s, unsigned base, long *vp)
201 {
202 long long v;
203
204 v = strtoll(s, NULL, base);
205 if (v < LONG_MIN || LONG_MAX < v)
206 return -ERANGE;
207 *vp = v;
208 return 0;
209 }
210
211 static inline long
simple_strtol(const char * s,char ** endp,unsigned base)212 simple_strtol(const char *s, char **endp, unsigned base)
213 {
214 long v;
215
216 *endp = NULL; /* paranoia */
217 v = strtoll(s, endp, base);
218 if (v < LONG_MIN || LONG_MAX < v)
219 return 0;
220 return v;
221 }
222
223 static __inline char * __printflike(2, 0)
kvasprintf(gfp_t gfp,const char * fmt,va_list va)224 kvasprintf(gfp_t gfp, const char *fmt, va_list va)
225 {
226 va_list tva;
227 char *str;
228 int len, len1 __diagused;
229
230 va_copy(tva, va);
231 len = vsnprintf(NULL, 0, fmt, tva);
232 va_end(tva);
233 str = kmalloc(len + 1, gfp);
234 if (str == NULL)
235 return NULL;
236 len1 = vsnprintf(str, len + 1, fmt, va);
237 KASSERT(len1 == len);
238
239 return str;
240 }
241
242 static __inline char * __printflike(2, 3)
kasprintf(gfp_t gfp,const char * fmt,...)243 kasprintf(gfp_t gfp, const char *fmt, ...)
244 {
245 va_list va;
246 char *str;
247
248 va_start(va, fmt);
249 str = kvasprintf(gfp, fmt, va);
250 va_end(va);
251
252 return str;
253 }
254
255 static inline void __user *
u64_to_user_ptr(uint64_t addr)256 u64_to_user_ptr(uint64_t addr)
257 {
258
259 return (void __user *)(uintptr_t)addr;
260 }
261
262 #define TAINT_MACHINE_CHECK 0
263 #define TAINT_WARN 1
264
265 #define LOCKDEP_STILL_OK 0
266
267 static inline void
add_taint(unsigned taint,int lockdep)268 add_taint(unsigned taint, int lockdep)
269 {
270 }
271
272 #define DFEINE_STATIC_KEY_FALSE(FLAG) \
273 bool FLAG = false
274
275 static inline bool
static_branch_likely(const bool * flagp)276 static_branch_likely(const bool *flagp)
277 {
278 return __predict_true(*flagp);
279 }
280
281 static inline int
sscanf(const char * fmt,...)282 sscanf(const char *fmt, ...)
283 {
284 return 0; /* XXX */
285 }
286
287 #endif /* _LINUX_KERNEL_H_ */
288