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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | #ifndef _LINUX_KERNEL_H |
3 | #define _LINUX_KERNEL_H | |
4 | ||
1da177e4 LT |
5 | |
6 | #include <stdarg.h> | |
54d50897 | 7 | #include <linux/limits.h> |
1da177e4 LT |
8 | #include <linux/linkage.h> |
9 | #include <linux/stddef.h> | |
10 | #include <linux/types.h> | |
11 | #include <linux/compiler.h> | |
12 | #include <linux/bitops.h> | |
f0d1b0b3 | 13 | #include <linux/log2.h> |
e0deaff4 | 14 | #include <linux/typecheck.h> |
968ab183 | 15 | #include <linux/printk.h> |
c7acec71 | 16 | #include <linux/build_bug.h> |
1da177e4 | 17 | #include <asm/byteorder.h> |
c461aed3 | 18 | #include <asm/div64.h> |
607ca46e | 19 | #include <uapi/linux/kernel.h> |
1da177e4 | 20 | |
1da177e4 LT |
21 | #define STACK_MAGIC 0xdeadbeef |
22 | ||
e8c97af0 RD |
23 | /** |
24 | * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value | |
25 | * @x: value to repeat | |
26 | * | |
27 | * NOTE: @x is not checked for > 0xff; larger values produce odd results. | |
28 | */ | |
44696908 DM |
29 | #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x)) |
30 | ||
3ca45a46 | 31 | /* @a is a power of 2 value */ |
a79ff731 | 32 | #define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) |
ed067d4a | 33 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a)) |
9f93ff5b | 34 | #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask)) |
a83308e6 | 35 | #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) |
229f5879 | 36 | #define PTR_ALIGN_DOWN(p, a) ((typeof(p))ALIGN_DOWN((unsigned long)(p), (a))) |
f10db627 | 37 | #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) |
2ea58144 | 38 | |
d3849953 CH |
39 | /* generic data direction definitions */ |
40 | #define READ 0 | |
41 | #define WRITE 1 | |
42 | ||
e8c97af0 RD |
43 | /** |
44 | * ARRAY_SIZE - get the number of elements in array @arr | |
45 | * @arr: array to be sized | |
46 | */ | |
c5e631cf RR |
47 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) |
48 | ||
3ed605bc GP |
49 | #define u64_to_user_ptr(x) ( \ |
50 | { \ | |
a0fe2c64 JH |
51 | typecheck(u64, (x)); \ |
52 | (void __user *)(uintptr_t)(x); \ | |
3ed605bc GP |
53 | } \ |
54 | ) | |
55 | ||
9b3be9f9 YL |
56 | /* |
57 | * This looks more complex than it should be. But we need to | |
58 | * get the type for the ~ right in round_down (it needs to be | |
59 | * as wide as the result!), and we want to evaluate the macro | |
60 | * arguments just once each. | |
61 | */ | |
62 | #define __round_mask(x, y) ((__typeof__(x))((y)-1)) | |
cedc5b6a KC |
63 | /** |
64 | * round_up - round up to next specified power of 2 | |
65 | * @x: the value to round | |
66 | * @y: multiple to round up to (must be a power of 2) | |
67 | * | |
68 | * Rounds @x up to next multiple of @y (which must be a power of 2). | |
69 | * To perform arbitrary rounding up, use roundup() below. | |
70 | */ | |
9b3be9f9 | 71 | #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) |
cedc5b6a KC |
72 | /** |
73 | * round_down - round down to next specified power of 2 | |
74 | * @x: the value to round | |
75 | * @y: multiple to round down to (must be a power of 2) | |
76 | * | |
77 | * Rounds @x down to next multiple of @y (which must be a power of 2). | |
78 | * To perform arbitrary rounding down, use rounddown() below. | |
79 | */ | |
9b3be9f9 YL |
80 | #define round_down(x, y) ((x) & ~__round_mask(x, y)) |
81 | ||
ce251e0e AD |
82 | #define typeof_member(T, m) typeof(((T*)0)->m) |
83 | ||
b5d3755a | 84 | #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP |
604df322 MY |
85 | |
86 | #define DIV_ROUND_DOWN_ULL(ll, d) \ | |
87 | ({ unsigned long long _tmp = (ll); do_div(_tmp, d); _tmp; }) | |
88 | ||
8f9fab48 VK |
89 | #define DIV_ROUND_UP_ULL(ll, d) \ |
90 | DIV_ROUND_DOWN_ULL((unsigned long long)(ll) + (d) - 1, (d)) | |
36a26c69 NB |
91 | |
92 | #if BITS_PER_LONG == 32 | |
93 | # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) | |
94 | #else | |
95 | # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d) | |
96 | #endif | |
074e61ec | 97 | |
cedc5b6a KC |
98 | /** |
99 | * roundup - round up to the next specified multiple | |
100 | * @x: the value to up | |
101 | * @y: multiple to round up to | |
102 | * | |
103 | * Rounds @x up to next multiple of @y. If @y will always be a power | |
104 | * of 2, consider using the faster round_up(). | |
cedc5b6a | 105 | */ |
b28efd54 EP |
106 | #define roundup(x, y) ( \ |
107 | { \ | |
b95c4d18 | 108 | typeof(y) __y = y; \ |
b28efd54 EP |
109 | (((x) + (__y - 1)) / __y) * __y; \ |
110 | } \ | |
111 | ) | |
cedc5b6a KC |
112 | /** |
113 | * rounddown - round down to next specified multiple | |
114 | * @x: the value to round | |
115 | * @y: multiple to round down to | |
116 | * | |
117 | * Rounds @x down to next multiple of @y. If @y will always be a power | |
118 | * of 2, consider using the faster round_down(). | |
119 | */ | |
686a0f3d EP |
120 | #define rounddown(x, y) ( \ |
121 | { \ | |
122 | typeof(x) __x = (x); \ | |
123 | __x - (__x % (y)); \ | |
124 | } \ | |
125 | ) | |
b6d86d3d GR |
126 | |
127 | /* | |
4f5901f5 NS |
128 | * Divide positive or negative dividend by positive or negative divisor |
129 | * and round to closest integer. Result is undefined for negative | |
e8c97af0 | 130 | * divisors if the dividend variable type is unsigned and for negative |
4f5901f5 | 131 | * dividends if the divisor variable type is unsigned. |
b6d86d3d | 132 | */ |
9fe06081 DW |
133 | #define DIV_ROUND_CLOSEST(x, divisor)( \ |
134 | { \ | |
b6d86d3d GR |
135 | typeof(x) __x = x; \ |
136 | typeof(divisor) __d = divisor; \ | |
c4e18497 | 137 | (((typeof(x))-1) > 0 || \ |
4f5901f5 NS |
138 | ((typeof(divisor))-1) > 0 || \ |
139 | (((__x) > 0) == ((__d) > 0))) ? \ | |
b6d86d3d GR |
140 | (((__x) + ((__d) / 2)) / (__d)) : \ |
141 | (((__x) - ((__d) / 2)) / (__d)); \ | |
9fe06081 DW |
142 | } \ |
143 | ) | |
f766093e JM |
144 | /* |
145 | * Same as above but for u64 dividends. divisor must be a 32-bit | |
146 | * number. | |
147 | */ | |
148 | #define DIV_ROUND_CLOSEST_ULL(x, divisor)( \ | |
149 | { \ | |
150 | typeof(divisor) __d = divisor; \ | |
151 | unsigned long long _tmp = (x) + (__d) / 2; \ | |
152 | do_div(_tmp, __d); \ | |
153 | _tmp; \ | |
154 | } \ | |
155 | ) | |
1da177e4 | 156 | |
9993bc63 SQ |
157 | /* |
158 | * Multiplies an integer by a fraction, while avoiding unnecessary | |
159 | * overflow or loss of precision. | |
160 | */ | |
161 | #define mult_frac(x, numer, denom)( \ | |
162 | { \ | |
163 | typeof(x) quot = (x) / (denom); \ | |
164 | typeof(x) rem = (x) % (denom); \ | |
165 | (quot * (numer)) + ((rem * (numer)) / (denom)); \ | |
166 | } \ | |
167 | ) | |
168 | ||
169 | ||
ca31e146 EGM |
170 | #define _RET_IP_ (unsigned long)__builtin_return_address(0) |
171 | #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) | |
172 | ||
72deb455 | 173 | #define sector_div(a, b) do_div(a, b) |
2da96acd | 174 | |
218e180e AM |
175 | /** |
176 | * upper_32_bits - return bits 32-63 of a number | |
177 | * @n: the number we're accessing | |
178 | * | |
179 | * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress | |
180 | * the "right shift count >= width of type" warning when that quantity is | |
181 | * 32-bits. | |
182 | */ | |
183 | #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) | |
184 | ||
204b885e JR |
185 | /** |
186 | * lower_32_bits - return bits 0-31 of a number | |
187 | * @n: the number we're accessing | |
188 | */ | |
189 | #define lower_32_bits(n) ((u32)(n)) | |
190 | ||
1da177e4 | 191 | struct completion; |
df2e71fb | 192 | struct pt_regs; |
193 | struct user; | |
1da177e4 | 194 | |
070cb065 UKK |
195 | #ifdef CONFIG_PREEMPT_VOLUNTARY |
196 | extern int _cond_resched(void); | |
197 | # define might_resched() _cond_resched() | |
198 | #else | |
199 | # define might_resched() do { } while (0) | |
200 | #endif | |
201 | ||
d902db1e | 202 | #ifdef CONFIG_DEBUG_ATOMIC_SLEEP |
568f1967 PZ |
203 | extern void ___might_sleep(const char *file, int line, int preempt_offset); |
204 | extern void __might_sleep(const char *file, int line, int preempt_offset); | |
205 | extern void __cant_sleep(const char *file, int line, int preempt_offset); | |
206 | ||
1da177e4 LT |
207 | /** |
208 | * might_sleep - annotation for functions that can sleep | |
209 | * | |
210 | * this macro will print a stack trace if it is executed in an atomic | |
312364f3 DV |
211 | * context (spinlock, irq-handler, ...). Additional sections where blocking is |
212 | * not allowed can be annotated with non_block_start() and non_block_end() | |
213 | * pairs. | |
1da177e4 LT |
214 | * |
215 | * This is a useful debugging help to be able to catch problems early and not | |
e20ec991 | 216 | * be bitten later when the calling function happens to sleep when it is not |
1da177e4 LT |
217 | * supposed to. |
218 | */ | |
f8cbd99b | 219 | # define might_sleep() \ |
e4aafea2 | 220 | do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) |
568f1967 PZ |
221 | /** |
222 | * cant_sleep - annotation for functions that cannot sleep | |
223 | * | |
224 | * this macro will print a stack trace if it is executed with preemption enabled | |
225 | */ | |
226 | # define cant_sleep() \ | |
227 | do { __cant_sleep(__FILE__, __LINE__, 0); } while (0) | |
00845eb9 | 228 | # define sched_annotate_sleep() (current->task_state_change = 0) |
312364f3 DV |
229 | /** |
230 | * non_block_start - annotate the start of section where sleeping is prohibited | |
231 | * | |
232 | * This is on behalf of the oom reaper, specifically when it is calling the mmu | |
233 | * notifiers. The problem is that if the notifier were to block on, for example, | |
234 | * mutex_lock() and if the process which holds that mutex were to perform a | |
235 | * sleeping memory allocation, the oom reaper is now blocked on completion of | |
236 | * that memory allocation. Other blocking calls like wait_event() pose similar | |
237 | * issues. | |
238 | */ | |
239 | # define non_block_start() (current->non_block_count++) | |
240 | /** | |
241 | * non_block_end - annotate the end of section where sleeping is prohibited | |
242 | * | |
243 | * Closes a section opened by non_block_start(). | |
244 | */ | |
245 | # define non_block_end() WARN_ON(current->non_block_count-- == 0) | |
1da177e4 | 246 | #else |
3427445a PZ |
247 | static inline void ___might_sleep(const char *file, int line, |
248 | int preempt_offset) { } | |
d894837f SK |
249 | static inline void __might_sleep(const char *file, int line, |
250 | int preempt_offset) { } | |
f8cbd99b | 251 | # define might_sleep() do { might_resched(); } while (0) |
568f1967 | 252 | # define cant_sleep() do { } while (0) |
1029a2b5 | 253 | # define sched_annotate_sleep() do { } while (0) |
312364f3 DV |
254 | # define non_block_start() do { } while (0) |
255 | # define non_block_end() do { } while (0) | |
1da177e4 LT |
256 | #endif |
257 | ||
368a5fa1 | 258 | #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) |
f8cbd99b | 259 | |
4e139c77 TG |
260 | #ifndef CONFIG_PREEMPT_RT |
261 | # define cant_migrate() cant_sleep() | |
262 | #else | |
263 | /* Placeholder for now */ | |
264 | # define cant_migrate() do { } while (0) | |
265 | #endif | |
266 | ||
c8299cb6 MN |
267 | /** |
268 | * abs - return absolute value of an argument | |
8f57e4d9 MN |
269 | * @x: the value. If it is unsigned type, it is converted to signed type first. |
270 | * char is treated as if it was signed (regardless of whether it really is) | |
271 | * but the macro's return type is preserved as char. | |
c8299cb6 | 272 | * |
8f57e4d9 | 273 | * Return: an absolute value of x. |
71a90484 | 274 | */ |
8f57e4d9 MN |
275 | #define abs(x) __abs_choose_expr(x, long long, \ |
276 | __abs_choose_expr(x, long, \ | |
277 | __abs_choose_expr(x, int, \ | |
278 | __abs_choose_expr(x, short, \ | |
279 | __abs_choose_expr(x, char, \ | |
280 | __builtin_choose_expr( \ | |
281 | __builtin_types_compatible_p(typeof(x), char), \ | |
282 | (char)({ signed char __x = (x); __x<0?-__x:__x; }), \ | |
283 | ((void)0))))))) | |
284 | ||
285 | #define __abs_choose_expr(x, type, other) __builtin_choose_expr( \ | |
286 | __builtin_types_compatible_p(typeof(x), signed type) || \ | |
287 | __builtin_types_compatible_p(typeof(x), unsigned type), \ | |
288 | ({ signed type __x = (x); __x < 0 ? -__x : __x; }), other) | |
c8299cb6 | 289 | |
89770b0a DB |
290 | /** |
291 | * reciprocal_scale - "scale" a value into range [0, ep_ro) | |
292 | * @val: value | |
293 | * @ep_ro: right open interval endpoint | |
294 | * | |
295 | * Perform a "reciprocal multiplication" in order to "scale" a value into | |
e8c97af0 | 296 | * range [0, @ep_ro), where the upper interval endpoint is right-open. |
89770b0a | 297 | * This is useful, e.g. for accessing a index of an array containing |
e8c97af0 | 298 | * @ep_ro elements, for example. Think of it as sort of modulus, only that |
89770b0a DB |
299 | * the result isn't that of modulo. ;) Note that if initial input is a |
300 | * small value, then result will return 0. | |
301 | * | |
e8c97af0 | 302 | * Return: a result based on @val in interval [0, @ep_ro). |
89770b0a DB |
303 | */ |
304 | static inline u32 reciprocal_scale(u32 val, u32 ep_ro) | |
305 | { | |
306 | return (u32)(((u64) val * ep_ro) >> 32); | |
307 | } | |
308 | ||
386e7906 AL |
309 | #if defined(CONFIG_MMU) && \ |
310 | (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP)) | |
9ec23531 DH |
311 | #define might_fault() __might_fault(__FILE__, __LINE__) |
312 | void __might_fault(const char *file, int line); | |
3ee1afa3 | 313 | #else |
662bbcb2 | 314 | static inline void might_fault(void) { } |
3ee1afa3 NP |
315 | #endif |
316 | ||
e041c683 | 317 | extern struct atomic_notifier_head panic_notifier_list; |
c7ff0d9c | 318 | extern long (*panic_blink)(int state); |
9402c95f | 319 | __printf(1, 2) |
9af6528e | 320 | void panic(const char *fmt, ...) __noreturn __cold; |
ebc41f20 | 321 | void nmi_panic(struct pt_regs *regs, const char *msg); |
dd287796 AM |
322 | extern void oops_enter(void); |
323 | extern void oops_exit(void); | |
79076e12 | 324 | extern bool oops_may_print(void); |
9af6528e PZ |
325 | void do_exit(long error_code) __noreturn; |
326 | void complete_and_exit(struct completion *, long) __noreturn; | |
33ee3b2e AD |
327 | |
328 | /* Internal, do not use. */ | |
329 | int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); | |
330 | int __must_check _kstrtol(const char *s, unsigned int base, long *res); | |
331 | ||
332 | int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); | |
333 | int __must_check kstrtoll(const char *s, unsigned int base, long long *res); | |
4c925d60 EZ |
334 | |
335 | /** | |
336 | * kstrtoul - convert a string to an unsigned long | |
337 | * @s: The start of the string. The string must be null-terminated, and may also | |
338 | * include a single newline before its terminating null. The first character | |
339 | * may also be a plus sign, but not a minus sign. | |
340 | * @base: The number base to use. The maximum supported base is 16. If base is | |
341 | * given as 0, then the base of the string is automatically detected with the | |
342 | * conventional semantics - If it begins with 0x the number will be parsed as a | |
343 | * hexadecimal (case insensitive), if it otherwise begins with 0, it will be | |
344 | * parsed as an octal number. Otherwise it will be parsed as a decimal. | |
345 | * @res: Where to write the result of the conversion on success. | |
346 | * | |
347 | * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. | |
ef0f2685 | 348 | * Preferred over simple_strtoul(). Return code must be checked. |
4c925d60 | 349 | */ |
33ee3b2e AD |
350 | static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) |
351 | { | |
352 | /* | |
353 | * We want to shortcut function call, but | |
354 | * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. | |
355 | */ | |
356 | if (sizeof(unsigned long) == sizeof(unsigned long long) && | |
357 | __alignof__(unsigned long) == __alignof__(unsigned long long)) | |
358 | return kstrtoull(s, base, (unsigned long long *)res); | |
359 | else | |
360 | return _kstrtoul(s, base, res); | |
361 | } | |
362 | ||
4c925d60 EZ |
363 | /** |
364 | * kstrtol - convert a string to a long | |
365 | * @s: The start of the string. The string must be null-terminated, and may also | |
366 | * include a single newline before its terminating null. The first character | |
367 | * may also be a plus sign or a minus sign. | |
368 | * @base: The number base to use. The maximum supported base is 16. If base is | |
369 | * given as 0, then the base of the string is automatically detected with the | |
370 | * conventional semantics - If it begins with 0x the number will be parsed as a | |
371 | * hexadecimal (case insensitive), if it otherwise begins with 0, it will be | |
372 | * parsed as an octal number. Otherwise it will be parsed as a decimal. | |
373 | * @res: Where to write the result of the conversion on success. | |
374 | * | |
375 | * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. | |
ef0f2685 | 376 | * Preferred over simple_strtol(). Return code must be checked. |
4c925d60 | 377 | */ |
33ee3b2e AD |
378 | static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) |
379 | { | |
380 | /* | |
381 | * We want to shortcut function call, but | |
382 | * __builtin_types_compatible_p(long, long long) = 0. | |
383 | */ | |
384 | if (sizeof(long) == sizeof(long long) && | |
385 | __alignof__(long) == __alignof__(long long)) | |
386 | return kstrtoll(s, base, (long long *)res); | |
387 | else | |
388 | return _kstrtol(s, base, res); | |
389 | } | |
390 | ||
391 | int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); | |
392 | int __must_check kstrtoint(const char *s, unsigned int base, int *res); | |
393 | ||
394 | static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) | |
395 | { | |
396 | return kstrtoull(s, base, res); | |
397 | } | |
398 | ||
399 | static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) | |
400 | { | |
401 | return kstrtoll(s, base, res); | |
402 | } | |
403 | ||
404 | static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) | |
405 | { | |
406 | return kstrtouint(s, base, res); | |
407 | } | |
408 | ||
409 | static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) | |
410 | { | |
411 | return kstrtoint(s, base, res); | |
412 | } | |
413 | ||
414 | int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); | |
415 | int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); | |
416 | int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); | |
417 | int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); | |
ef951599 | 418 | int __must_check kstrtobool(const char *s, bool *res); |
33ee3b2e | 419 | |
c196e32a AD |
420 | int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); |
421 | int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); | |
422 | int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); | |
423 | int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); | |
424 | int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); | |
425 | int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); | |
426 | int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); | |
427 | int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); | |
428 | int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); | |
429 | int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); | |
ef951599 | 430 | int __must_check kstrtobool_from_user(const char __user *s, size_t count, bool *res); |
c196e32a AD |
431 | |
432 | static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) | |
433 | { | |
434 | return kstrtoull_from_user(s, count, base, res); | |
435 | } | |
436 | ||
437 | static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) | |
438 | { | |
439 | return kstrtoll_from_user(s, count, base, res); | |
440 | } | |
441 | ||
442 | static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) | |
443 | { | |
444 | return kstrtouint_from_user(s, count, base, res); | |
445 | } | |
446 | ||
447 | static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) | |
448 | { | |
449 | return kstrtoint_from_user(s, count, base, res); | |
450 | } | |
451 | ||
885e68e8 AS |
452 | /* |
453 | * Use kstrto<foo> instead. | |
454 | * | |
455 | * NOTE: simple_strto<foo> does not check for the range overflow and, | |
456 | * depending on the input, may give interesting results. | |
457 | * | |
458 | * Use these functions if and only if you cannot use kstrto<foo>, because | |
459 | * the conversion ends on the first non-digit character, which may be far | |
460 | * beyond the supported range. It might be useful to parse the strings like | |
461 | * 10x50 or 12:21 without altering original string or temporary buffer in use. | |
462 | * Keep in mind above caveat. | |
463 | */ | |
67d0a075 | 464 | |
1da177e4 LT |
465 | extern unsigned long simple_strtoul(const char *,char **,unsigned int); |
466 | extern long simple_strtol(const char *,char **,unsigned int); | |
467 | extern unsigned long long simple_strtoull(const char *,char **,unsigned int); | |
468 | extern long long simple_strtoll(const char *,char **,unsigned int); | |
33ee3b2e | 469 | |
d1be35cb AV |
470 | extern int num_to_str(char *buf, int size, |
471 | unsigned long long num, unsigned int width); | |
1ac101a5 | 472 | |
67d0a075 JP |
473 | /* lib/printf utilities */ |
474 | ||
b9075fa9 JP |
475 | extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); |
476 | extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); | |
477 | extern __printf(3, 4) | |
478 | int snprintf(char *buf, size_t size, const char *fmt, ...); | |
479 | extern __printf(3, 0) | |
480 | int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); | |
481 | extern __printf(3, 4) | |
482 | int scnprintf(char *buf, size_t size, const char *fmt, ...); | |
483 | extern __printf(3, 0) | |
484 | int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); | |
48a27055 | 485 | extern __printf(2, 3) __malloc |
b9075fa9 | 486 | char *kasprintf(gfp_t gfp, const char *fmt, ...); |
48a27055 | 487 | extern __printf(2, 0) __malloc |
8db14860 | 488 | char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); |
0a9df786 RV |
489 | extern __printf(2, 0) |
490 | const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list args); | |
1da177e4 | 491 | |
6061d949 JP |
492 | extern __scanf(2, 3) |
493 | int sscanf(const char *, const char *, ...); | |
494 | extern __scanf(2, 0) | |
495 | int vsscanf(const char *, const char *, va_list); | |
1da177e4 LT |
496 | |
497 | extern int get_option(char **str, int *pint); | |
498 | extern char *get_options(const char *str, int nints, int *ints); | |
d974ae37 | 499 | extern unsigned long long memparse(const char *ptr, char **retptr); |
6ccc72b8 | 500 | extern bool parse_option_str(const char *str, const char *option); |
f51b17c8 | 501 | extern char *next_arg(char *args, char **param, char **val); |
1da177e4 | 502 | |
5e376613 | 503 | extern int core_kernel_text(unsigned long addr); |
9fbcc57a | 504 | extern int init_kernel_text(unsigned long addr); |
cdbe61bf | 505 | extern int core_kernel_data(unsigned long addr); |
1da177e4 LT |
506 | extern int __kernel_text_address(unsigned long addr); |
507 | extern int kernel_text_address(unsigned long addr); | |
ab7476cf | 508 | extern int func_ptr_is_kernel_text(void *ptr); |
ab7476cf | 509 | |
9f615894 | 510 | u64 int_pow(u64 base, unsigned int exp); |
1da177e4 LT |
511 | unsigned long int_sqrt(unsigned long); |
512 | ||
47a36163 CM |
513 | #if BITS_PER_LONG < 64 |
514 | u32 int_sqrt64(u64 x); | |
515 | #else | |
516 | static inline u32 int_sqrt64(u64 x) | |
517 | { | |
518 | return (u32)int_sqrt(x); | |
519 | } | |
520 | #endif | |
521 | ||
60c958d8 GP |
522 | #ifdef CONFIG_SMP |
523 | extern unsigned int sysctl_oops_all_cpu_backtrace; | |
524 | #else | |
525 | #define sysctl_oops_all_cpu_backtrace 0 | |
526 | #endif /* CONFIG_SMP */ | |
527 | ||
1da177e4 LT |
528 | extern void bust_spinlocks(int yes); |
529 | extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ | |
aa727107 | 530 | extern int panic_timeout; |
81c9d43f | 531 | extern unsigned long panic_print; |
1da177e4 | 532 | extern int panic_on_oops; |
8da5adda | 533 | extern int panic_on_unrecovered_nmi; |
5211a242 | 534 | extern int panic_on_io_nmi; |
9e3961a0 | 535 | extern int panic_on_warn; |
db38d5c1 RA |
536 | extern unsigned long panic_on_taint; |
537 | extern bool panic_on_taint_nousertaint; | |
088e9d25 | 538 | extern int sysctl_panic_on_rcu_stall; |
55af7796 | 539 | extern int sysctl_panic_on_stackoverflow; |
5375b708 HD |
540 | |
541 | extern bool crash_kexec_post_notifiers; | |
542 | ||
1717f209 HK |
543 | /* |
544 | * panic_cpu is used for synchronizing panic() and crash_kexec() execution. It | |
545 | * holds a CPU number which is executing panic() currently. A value of | |
546 | * PANIC_CPU_INVALID means no CPU has entered panic() or crash_kexec(). | |
547 | */ | |
548 | extern atomic_t panic_cpu; | |
549 | #define PANIC_CPU_INVALID -1 | |
550 | ||
5800dc3c JB |
551 | /* |
552 | * Only to be used by arch init code. If the user over-wrote the default | |
553 | * CONFIG_PANIC_TIMEOUT, honor it. | |
554 | */ | |
555 | static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout) | |
556 | { | |
557 | if (panic_timeout == arch_default_timeout) | |
558 | panic_timeout = timeout; | |
559 | } | |
1da177e4 | 560 | extern const char *print_tainted(void); |
373d4d09 RR |
561 | enum lockdep_ok { |
562 | LOCKDEP_STILL_OK, | |
563 | LOCKDEP_NOW_UNRELIABLE | |
564 | }; | |
565 | extern void add_taint(unsigned flag, enum lockdep_ok); | |
25ddbb18 AK |
566 | extern int test_taint(unsigned flag); |
567 | extern unsigned long get_taint(void); | |
b920de1b | 568 | extern int root_mountflags; |
1da177e4 | 569 | |
2ce802f6 TH |
570 | extern bool early_boot_irqs_disabled; |
571 | ||
69a78ff2 TG |
572 | /* |
573 | * Values used for system_state. Ordering of the states must not be changed | |
574 | * as code checks for <, <=, >, >= STATE. | |
575 | */ | |
1da177e4 LT |
576 | extern enum system_states { |
577 | SYSTEM_BOOTING, | |
69a78ff2 | 578 | SYSTEM_SCHEDULING, |
1da177e4 LT |
579 | SYSTEM_RUNNING, |
580 | SYSTEM_HALT, | |
581 | SYSTEM_POWER_OFF, | |
582 | SYSTEM_RESTART, | |
c1a957d1 | 583 | SYSTEM_SUSPEND, |
1da177e4 LT |
584 | } system_state; |
585 | ||
47d4b263 | 586 | /* This cannot be an enum because some may be used in assembly source. */ |
25ddbb18 AK |
587 | #define TAINT_PROPRIETARY_MODULE 0 |
588 | #define TAINT_FORCED_MODULE 1 | |
8c90487c | 589 | #define TAINT_CPU_OUT_OF_SPEC 2 |
25ddbb18 AK |
590 | #define TAINT_FORCED_RMMOD 3 |
591 | #define TAINT_MACHINE_CHECK 4 | |
592 | #define TAINT_BAD_PAGE 5 | |
593 | #define TAINT_USER 6 | |
594 | #define TAINT_DIE 7 | |
595 | #define TAINT_OVERRIDDEN_ACPI_TABLE 8 | |
596 | #define TAINT_WARN 9 | |
26e9a397 | 597 | #define TAINT_CRAP 10 |
92946bc7 | 598 | #define TAINT_FIRMWARE_WORKAROUND 11 |
2449b8ba | 599 | #define TAINT_OOT_MODULE 12 |
66cc69e3 | 600 | #define TAINT_UNSIGNED_MODULE 13 |
69361eef | 601 | #define TAINT_SOFTLOCKUP 14 |
c5f45465 | 602 | #define TAINT_LIVEPATCH 15 |
4efb442c | 603 | #define TAINT_AUX 16 |
bc4f2f54 KC |
604 | #define TAINT_RANDSTRUCT 17 |
605 | #define TAINT_FLAGS_COUNT 18 | |
db38d5c1 | 606 | #define TAINT_FLAGS_MAX ((1UL << TAINT_FLAGS_COUNT) - 1) |
7fd8329b PM |
607 | |
608 | struct taint_flag { | |
5eb7c0d0 LF |
609 | char c_true; /* character printed when tainted */ |
610 | char c_false; /* character printed when not tainted */ | |
7fd8329b PM |
611 | bool module; /* also show as a per-module taint flag */ |
612 | }; | |
613 | ||
614 | extern const struct taint_flag taint_flags[TAINT_FLAGS_COUNT]; | |
1da177e4 | 615 | |
3fc95772 HH |
616 | extern const char hex_asc[]; |
617 | #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] | |
618 | #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] | |
619 | ||
55036ba7 | 620 | static inline char *hex_byte_pack(char *buf, u8 byte) |
3fc95772 HH |
621 | { |
622 | *buf++ = hex_asc_hi(byte); | |
623 | *buf++ = hex_asc_lo(byte); | |
624 | return buf; | |
625 | } | |
99eaf3c4 | 626 | |
c26d436c AN |
627 | extern const char hex_asc_upper[]; |
628 | #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)] | |
629 | #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4] | |
630 | ||
631 | static inline char *hex_byte_pack_upper(char *buf, u8 byte) | |
632 | { | |
633 | *buf++ = hex_asc_upper_hi(byte); | |
634 | *buf++ = hex_asc_upper_lo(byte); | |
635 | return buf; | |
636 | } | |
637 | ||
90378889 | 638 | extern int hex_to_bin(char ch); |
b7804983 | 639 | extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); |
53d91c5c | 640 | extern char *bin2hex(char *dst, const void *src, size_t count); |
90378889 | 641 | |
a69f5edb | 642 | bool mac_pton(const char *s, u8 *mac); |
4cd5773a | 643 | |
526211bc IM |
644 | /* |
645 | * General tracing related utility functions - trace_printk(), | |
2002c258 SR |
646 | * tracing_on/tracing_off and tracing_start()/tracing_stop |
647 | * | |
648 | * Use tracing_on/tracing_off when you want to quickly turn on or off | |
649 | * tracing. It simply enables or disables the recording of the trace events. | |
156f5a78 | 650 | * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on |
2002c258 SR |
651 | * file, which gives a means for the kernel and userspace to interact. |
652 | * Place a tracing_off() in the kernel where you want tracing to end. | |
653 | * From user space, examine the trace, and then echo 1 > tracing_on | |
654 | * to continue tracing. | |
655 | * | |
656 | * tracing_stop/tracing_start has slightly more overhead. It is used | |
657 | * by things like suspend to ram where disabling the recording of the | |
658 | * trace is not enough, but tracing must actually stop because things | |
659 | * like calling smp_processor_id() may crash the system. | |
660 | * | |
661 | * Most likely, you want to use tracing_on/tracing_off. | |
526211bc | 662 | */ |
cecbca96 FW |
663 | |
664 | enum ftrace_dump_mode { | |
665 | DUMP_NONE, | |
666 | DUMP_ALL, | |
667 | DUMP_ORIG, | |
668 | }; | |
669 | ||
526211bc | 670 | #ifdef CONFIG_TRACING |
93d68e52 SR |
671 | void tracing_on(void); |
672 | void tracing_off(void); | |
673 | int tracing_is_on(void); | |
ad909e21 SRRH |
674 | void tracing_snapshot(void); |
675 | void tracing_snapshot_alloc(void); | |
93d68e52 | 676 | |
526211bc IM |
677 | extern void tracing_start(void); |
678 | extern void tracing_stop(void); | |
526211bc | 679 | |
b9075fa9 JP |
680 | static inline __printf(1, 2) |
681 | void ____trace_printk_check_format(const char *fmt, ...) | |
769b0441 FW |
682 | { |
683 | } | |
684 | #define __trace_printk_check_format(fmt, args...) \ | |
685 | do { \ | |
686 | if (0) \ | |
687 | ____trace_printk_check_format(fmt, ##args); \ | |
688 | } while (0) | |
689 | ||
526211bc IM |
690 | /** |
691 | * trace_printk - printf formatting in the ftrace buffer | |
692 | * @fmt: the printf format for printing | |
693 | * | |
e8c97af0 RD |
694 | * Note: __trace_printk is an internal function for trace_printk() and |
695 | * the @ip is passed in via the trace_printk() macro. | |
526211bc IM |
696 | * |
697 | * This function allows a kernel developer to debug fast path sections | |
698 | * that printk is not appropriate for. By scattering in various | |
699 | * printk like tracing in the code, a developer can quickly see | |
700 | * where problems are occurring. | |
701 | * | |
702 | * This is intended as a debugging tool for the developer only. | |
703 | * Please refrain from leaving trace_printks scattered around in | |
09ae7234 | 704 | * your code. (Extra memory is used for special buffers that are |
e8c97af0 | 705 | * allocated when trace_printk() is used.) |
9d3c752c | 706 | * |
8730662d | 707 | * A little optimization trick is done here. If there's only one |
9d3c752c SRRH |
708 | * argument, there's no need to scan the string for printf formats. |
709 | * The trace_puts() will suffice. But how can we take advantage of | |
710 | * using trace_puts() when trace_printk() has only one argument? | |
711 | * By stringifying the args and checking the size we can tell | |
712 | * whether or not there are args. __stringify((__VA_ARGS__)) will | |
713 | * turn into "()\0" with a size of 3 when there are no args, anything | |
714 | * else will be bigger. All we need to do is define a string to this, | |
715 | * and then take its size and compare to 3. If it's bigger, use | |
716 | * do_trace_printk() otherwise, optimize it to trace_puts(). Then just | |
717 | * let gcc optimize the rest. | |
526211bc | 718 | */ |
769b0441 | 719 | |
9d3c752c SRRH |
720 | #define trace_printk(fmt, ...) \ |
721 | do { \ | |
722 | char _______STR[] = __stringify((__VA_ARGS__)); \ | |
723 | if (sizeof(_______STR) > 3) \ | |
724 | do_trace_printk(fmt, ##__VA_ARGS__); \ | |
725 | else \ | |
726 | trace_puts(fmt); \ | |
727 | } while (0) | |
728 | ||
729 | #define do_trace_printk(fmt, args...) \ | |
769b0441 | 730 | do { \ |
3debb0a9 | 731 | static const char *trace_printk_fmt __used \ |
07d777fe SR |
732 | __attribute__((section("__trace_printk_fmt"))) = \ |
733 | __builtin_constant_p(fmt) ? fmt : NULL; \ | |
734 | \ | |
769b0441 | 735 | __trace_printk_check_format(fmt, ##args); \ |
48ead020 | 736 | \ |
07d777fe | 737 | if (__builtin_constant_p(fmt)) \ |
48ead020 | 738 | __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ |
07d777fe SR |
739 | else \ |
740 | __trace_printk(_THIS_IP_, fmt, ##args); \ | |
769b0441 FW |
741 | } while (0) |
742 | ||
b9075fa9 JP |
743 | extern __printf(2, 3) |
744 | int __trace_bprintk(unsigned long ip, const char *fmt, ...); | |
48ead020 | 745 | |
b9075fa9 JP |
746 | extern __printf(2, 3) |
747 | int __trace_printk(unsigned long ip, const char *fmt, ...); | |
769b0441 | 748 | |
09ae7234 SRRH |
749 | /** |
750 | * trace_puts - write a string into the ftrace buffer | |
751 | * @str: the string to record | |
752 | * | |
753 | * Note: __trace_bputs is an internal function for trace_puts and | |
754 | * the @ip is passed in via the trace_puts macro. | |
755 | * | |
756 | * This is similar to trace_printk() but is made for those really fast | |
e8c97af0 | 757 | * paths that a developer wants the least amount of "Heisenbug" effects, |
09ae7234 SRRH |
758 | * where the processing of the print format is still too much. |
759 | * | |
760 | * This function allows a kernel developer to debug fast path sections | |
761 | * that printk is not appropriate for. By scattering in various | |
762 | * printk like tracing in the code, a developer can quickly see | |
763 | * where problems are occurring. | |
764 | * | |
765 | * This is intended as a debugging tool for the developer only. | |
766 | * Please refrain from leaving trace_puts scattered around in | |
767 | * your code. (Extra memory is used for special buffers that are | |
e8c97af0 | 768 | * allocated when trace_puts() is used.) |
09ae7234 SRRH |
769 | * |
770 | * Returns: 0 if nothing was written, positive # if string was. | |
771 | * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used) | |
772 | */ | |
773 | ||
09ae7234 | 774 | #define trace_puts(str) ({ \ |
3debb0a9 | 775 | static const char *trace_printk_fmt __used \ |
09ae7234 SRRH |
776 | __attribute__((section("__trace_printk_fmt"))) = \ |
777 | __builtin_constant_p(str) ? str : NULL; \ | |
778 | \ | |
779 | if (__builtin_constant_p(str)) \ | |
780 | __trace_bputs(_THIS_IP_, trace_printk_fmt); \ | |
781 | else \ | |
782 | __trace_puts(_THIS_IP_, str, strlen(str)); \ | |
783 | }) | |
bcf312cf SR |
784 | extern int __trace_bputs(unsigned long ip, const char *str); |
785 | extern int __trace_puts(unsigned long ip, const char *str, int size); | |
09ae7234 | 786 | |
c142be8e | 787 | extern void trace_dump_stack(int skip); |
03889384 | 788 | |
48ead020 FW |
789 | /* |
790 | * The double __builtin_constant_p is because gcc will give us an error | |
791 | * if we try to allocate the static variable to fmt if it is not a | |
792 | * constant. Even with the outer if statement. | |
793 | */ | |
769b0441 FW |
794 | #define ftrace_vprintk(fmt, vargs) \ |
795 | do { \ | |
48ead020 | 796 | if (__builtin_constant_p(fmt)) { \ |
3debb0a9 | 797 | static const char *trace_printk_fmt __used \ |
48ead020 FW |
798 | __attribute__((section("__trace_printk_fmt"))) = \ |
799 | __builtin_constant_p(fmt) ? fmt : NULL; \ | |
7bffc23e | 800 | \ |
48ead020 FW |
801 | __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ |
802 | } else \ | |
803 | __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ | |
769b0441 FW |
804 | } while (0) |
805 | ||
8db14860 | 806 | extern __printf(2, 0) int |
48ead020 FW |
807 | __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); |
808 | ||
8db14860 | 809 | extern __printf(2, 0) int |
526211bc | 810 | __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); |
769b0441 | 811 | |
cecbca96 | 812 | extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); |
526211bc | 813 | #else |
526211bc IM |
814 | static inline void tracing_start(void) { } |
815 | static inline void tracing_stop(void) { } | |
e67bc51e | 816 | static inline void trace_dump_stack(int skip) { } |
93d68e52 SR |
817 | |
818 | static inline void tracing_on(void) { } | |
819 | static inline void tracing_off(void) { } | |
820 | static inline int tracing_is_on(void) { return 0; } | |
ad909e21 SRRH |
821 | static inline void tracing_snapshot(void) { } |
822 | static inline void tracing_snapshot_alloc(void) { } | |
93d68e52 | 823 | |
60efc15a MH |
824 | static inline __printf(1, 2) |
825 | int trace_printk(const char *fmt, ...) | |
526211bc IM |
826 | { |
827 | return 0; | |
828 | } | |
8db14860 | 829 | static __printf(1, 0) inline int |
526211bc IM |
830 | ftrace_vprintk(const char *fmt, va_list ap) |
831 | { | |
832 | return 0; | |
833 | } | |
cecbca96 | 834 | static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } |
769b0441 | 835 | #endif /* CONFIG_TRACING */ |
526211bc | 836 | |
1da177e4 | 837 | /* |
3c8ba0d6 KC |
838 | * min()/max()/clamp() macros must accomplish three things: |
839 | * | |
840 | * - avoid multiple evaluations of the arguments (so side-effects like | |
841 | * "x++" happen only once) when non-constant. | |
842 | * - perform strict type-checking (to generate warnings instead of | |
843 | * nasty runtime surprises). See the "unnecessary" pointer comparison | |
844 | * in __typecheck(). | |
845 | * - retain result as a constant expressions when called with only | |
846 | * constant expressions (to avoid tripping VLA warnings in stack | |
847 | * allocation usage). | |
1da177e4 | 848 | */ |
3c8ba0d6 KC |
849 | #define __typecheck(x, y) \ |
850 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) | |
851 | ||
852 | /* | |
853 | * This returns a constant expression while determining if an argument is | |
854 | * a constant expression, most importantly without evaluating the argument. | |
855 | * Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de> | |
856 | */ | |
857 | #define __is_constexpr(x) \ | |
858 | (sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8))) | |
859 | ||
860 | #define __no_side_effects(x, y) \ | |
861 | (__is_constexpr(x) && __is_constexpr(y)) | |
862 | ||
863 | #define __safe_cmp(x, y) \ | |
864 | (__typecheck(x, y) && __no_side_effects(x, y)) | |
865 | ||
866 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y)) | |
867 | ||
e9092d0d LT |
868 | #define __cmp_once(x, y, unique_x, unique_y, op) ({ \ |
869 | typeof(x) unique_x = (x); \ | |
870 | typeof(y) unique_y = (y); \ | |
871 | __cmp(unique_x, unique_y, op); }) | |
872 | ||
873 | #define __careful_cmp(x, y, op) \ | |
874 | __builtin_choose_expr(__safe_cmp(x, y), \ | |
875 | __cmp(x, y, op), \ | |
876 | __cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op)) | |
e8c97af0 RD |
877 | |
878 | /** | |
879 | * min - return minimum of two values of the same or compatible types | |
880 | * @x: first value | |
881 | * @y: second value | |
882 | */ | |
3c8ba0d6 | 883 | #define min(x, y) __careful_cmp(x, y, <) |
e8c97af0 RD |
884 | |
885 | /** | |
886 | * max - return maximum of two values of the same or compatible types | |
887 | * @x: first value | |
888 | * @y: second value | |
889 | */ | |
3c8ba0d6 | 890 | #define max(x, y) __careful_cmp(x, y, >) |
bdf4bbaa | 891 | |
e8c97af0 RD |
892 | /** |
893 | * min3 - return minimum of three values | |
894 | * @x: first value | |
895 | * @y: second value | |
896 | * @z: third value | |
897 | */ | |
2e1d06e1 | 898 | #define min3(x, y, z) min((typeof(x))min(x, y), z) |
e8c97af0 RD |
899 | |
900 | /** | |
901 | * max3 - return maximum of three values | |
902 | * @x: first value | |
903 | * @y: second value | |
904 | * @z: third value | |
905 | */ | |
2e1d06e1 | 906 | #define max3(x, y, z) max((typeof(x))max(x, y), z) |
f27c85c5 | 907 | |
c8bf1336 MP |
908 | /** |
909 | * min_not_zero - return the minimum that is _not_ zero, unless both are zero | |
910 | * @x: value1 | |
911 | * @y: value2 | |
912 | */ | |
913 | #define min_not_zero(x, y) ({ \ | |
914 | typeof(x) __x = (x); \ | |
915 | typeof(y) __y = (y); \ | |
916 | __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) | |
917 | ||
bdf4bbaa HH |
918 | /** |
919 | * clamp - return a value clamped to a given range with strict typechecking | |
920 | * @val: current value | |
2e1d06e1 MN |
921 | * @lo: lowest allowable value |
922 | * @hi: highest allowable value | |
bdf4bbaa | 923 | * |
e8c97af0 RD |
924 | * This macro does strict typechecking of @lo/@hi to make sure they are of the |
925 | * same type as @val. See the unnecessary pointer comparisons. | |
bdf4bbaa | 926 | */ |
2e1d06e1 | 927 | #define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi) |
1da177e4 LT |
928 | |
929 | /* | |
930 | * ..and if you can't take the strict | |
931 | * types, you can specify one yourself. | |
932 | * | |
bdf4bbaa HH |
933 | * Or not use min/max/clamp at all, of course. |
934 | */ | |
e8c97af0 RD |
935 | |
936 | /** | |
937 | * min_t - return minimum of two values, using the specified type | |
938 | * @type: data type to use | |
939 | * @x: first value | |
940 | * @y: second value | |
941 | */ | |
3c8ba0d6 | 942 | #define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <) |
589a9785 | 943 | |
e8c97af0 RD |
944 | /** |
945 | * max_t - return maximum of two values, using the specified type | |
946 | * @type: data type to use | |
947 | * @x: first value | |
948 | * @y: second value | |
949 | */ | |
3c8ba0d6 | 950 | #define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >) |
bdf4bbaa HH |
951 | |
952 | /** | |
953 | * clamp_t - return a value clamped to a given range using a given type | |
954 | * @type: the type of variable to use | |
955 | * @val: current value | |
c185b07f MN |
956 | * @lo: minimum allowable value |
957 | * @hi: maximum allowable value | |
bdf4bbaa HH |
958 | * |
959 | * This macro does no typechecking and uses temporary variables of type | |
e8c97af0 | 960 | * @type to make all the comparisons. |
1da177e4 | 961 | */ |
c185b07f | 962 | #define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi) |
1da177e4 | 963 | |
bdf4bbaa HH |
964 | /** |
965 | * clamp_val - return a value clamped to a given range using val's type | |
966 | * @val: current value | |
c185b07f MN |
967 | * @lo: minimum allowable value |
968 | * @hi: maximum allowable value | |
bdf4bbaa HH |
969 | * |
970 | * This macro does no typechecking and uses temporary variables of whatever | |
e8c97af0 RD |
971 | * type the input argument @val is. This is useful when @val is an unsigned |
972 | * type and @lo and @hi are literals that will otherwise be assigned a signed | |
bdf4bbaa HH |
973 | * integer type. |
974 | */ | |
c185b07f | 975 | #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi) |
1da177e4 | 976 | |
91f68b73 | 977 | |
e8c97af0 RD |
978 | /** |
979 | * swap - swap values of @a and @b | |
980 | * @a: first value | |
981 | * @b: second value | |
91f68b73 | 982 | */ |
ac7b9004 PZ |
983 | #define swap(a, b) \ |
984 | do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) | |
91f68b73 | 985 | |
cf14f27f AS |
986 | /* This counts to 12. Any more, it will return 13th argument. */ |
987 | #define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n | |
988 | #define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) | |
989 | ||
990 | #define __CONCAT(a, b) a ## b | |
991 | #define CONCATENATE(a, b) __CONCAT(a, b) | |
992 | ||
1da177e4 LT |
993 | /** |
994 | * container_of - cast a member of a structure out to the containing structure | |
1da177e4 LT |
995 | * @ptr: the pointer to the member. |
996 | * @type: the type of the container struct this is embedded in. | |
997 | * @member: the name of the member within the struct. | |
998 | * | |
999 | */ | |
c7acec71 IA |
1000 | #define container_of(ptr, type, member) ({ \ |
1001 | void *__mptr = (void *)(ptr); \ | |
1002 | BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ | |
1003 | !__same_type(*(ptr), void), \ | |
1004 | "pointer type mismatch in container_of()"); \ | |
1005 | ((type *)(__mptr - offsetof(type, member))); }) | |
1da177e4 | 1006 | |
05e6557b N |
1007 | /** |
1008 | * container_of_safe - cast a member of a structure out to the containing structure | |
1009 | * @ptr: the pointer to the member. | |
1010 | * @type: the type of the container struct this is embedded in. | |
1011 | * @member: the name of the member within the struct. | |
1012 | * | |
1013 | * If IS_ERR_OR_NULL(ptr), ptr is returned unchanged. | |
1014 | */ | |
1015 | #define container_of_safe(ptr, type, member) ({ \ | |
1016 | void *__mptr = (void *)(ptr); \ | |
1017 | BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ | |
1018 | !__same_type(*(ptr), void), \ | |
1019 | "pointer type mismatch in container_of()"); \ | |
227abcc6 | 1020 | IS_ERR_OR_NULL(__mptr) ? ERR_CAST(__mptr) : \ |
05e6557b N |
1021 | ((type *)(__mptr - offsetof(type, member))); }) |
1022 | ||
b9d4f426 AL |
1023 | /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ |
1024 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD | |
1025 | # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD | |
1026 | #endif | |
9d00f92f | 1027 | |
58f86cc8 | 1028 | /* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */ |
28b8d0c8 GCM |
1029 | #define VERIFY_OCTAL_PERMISSIONS(perms) \ |
1030 | (BUILD_BUG_ON_ZERO((perms) < 0) + \ | |
1031 | BUILD_BUG_ON_ZERO((perms) > 0777) + \ | |
1032 | /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */ \ | |
1033 | BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) + \ | |
1034 | BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + \ | |
1035 | /* USER_WRITABLE >= GROUP_WRITABLE */ \ | |
1036 | BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) < (((perms) >> 3) & 2)) + \ | |
1037 | /* OTHER_WRITABLE? Generally considered a bad idea. */ \ | |
1038 | BUILD_BUG_ON_ZERO((perms) & 2) + \ | |
58f86cc8 | 1039 | (perms)) |
1da177e4 | 1040 | #endif |