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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> |
72deb455 | 20 | #include <asm/div64.h> |
1da177e4 | 21 | |
1da177e4 LT |
22 | #define STACK_MAGIC 0xdeadbeef |
23 | ||
e8c97af0 RD |
24 | /** |
25 | * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value | |
26 | * @x: value to repeat | |
27 | * | |
28 | * NOTE: @x is not checked for > 0xff; larger values produce odd results. | |
29 | */ | |
44696908 DM |
30 | #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x)) |
31 | ||
3ca45a46 | 32 | /* @a is a power of 2 value */ |
a79ff731 | 33 | #define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) |
ed067d4a | 34 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a)) |
9f93ff5b | 35 | #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask)) |
a83308e6 | 36 | #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((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 | ||
e8c97af0 RD |
82 | /** |
83 | * FIELD_SIZEOF - get the size of a struct's field | |
84 | * @t: the target struct | |
85 | * @f: the target struct's field | |
86 | * Return: the size of @f in the struct definition without having a | |
87 | * declared instance of @t. | |
88 | */ | |
4552d5dc | 89 | #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) |
e8c97af0 | 90 | |
b5d3755a | 91 | #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP |
604df322 MY |
92 | |
93 | #define DIV_ROUND_DOWN_ULL(ll, d) \ | |
94 | ({ unsigned long long _tmp = (ll); do_div(_tmp, d); _tmp; }) | |
95 | ||
8f9fab48 VK |
96 | #define DIV_ROUND_UP_ULL(ll, d) \ |
97 | DIV_ROUND_DOWN_ULL((unsigned long long)(ll) + (d) - 1, (d)) | |
36a26c69 NB |
98 | |
99 | #if BITS_PER_LONG == 32 | |
100 | # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) | |
101 | #else | |
102 | # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d) | |
103 | #endif | |
074e61ec | 104 | |
cedc5b6a KC |
105 | /** |
106 | * roundup - round up to the next specified multiple | |
107 | * @x: the value to up | |
108 | * @y: multiple to round up to | |
109 | * | |
110 | * Rounds @x up to next multiple of @y. If @y will always be a power | |
111 | * of 2, consider using the faster round_up(). | |
cedc5b6a | 112 | */ |
b28efd54 EP |
113 | #define roundup(x, y) ( \ |
114 | { \ | |
b95c4d18 | 115 | typeof(y) __y = y; \ |
b28efd54 EP |
116 | (((x) + (__y - 1)) / __y) * __y; \ |
117 | } \ | |
118 | ) | |
cedc5b6a KC |
119 | /** |
120 | * rounddown - round down to next specified multiple | |
121 | * @x: the value to round | |
122 | * @y: multiple to round down to | |
123 | * | |
124 | * Rounds @x down to next multiple of @y. If @y will always be a power | |
125 | * of 2, consider using the faster round_down(). | |
126 | */ | |
686a0f3d EP |
127 | #define rounddown(x, y) ( \ |
128 | { \ | |
129 | typeof(x) __x = (x); \ | |
130 | __x - (__x % (y)); \ | |
131 | } \ | |
132 | ) | |
b6d86d3d GR |
133 | |
134 | /* | |
4f5901f5 NS |
135 | * Divide positive or negative dividend by positive or negative divisor |
136 | * and round to closest integer. Result is undefined for negative | |
e8c97af0 | 137 | * divisors if the dividend variable type is unsigned and for negative |
4f5901f5 | 138 | * dividends if the divisor variable type is unsigned. |
b6d86d3d | 139 | */ |
9fe06081 DW |
140 | #define DIV_ROUND_CLOSEST(x, divisor)( \ |
141 | { \ | |
b6d86d3d GR |
142 | typeof(x) __x = x; \ |
143 | typeof(divisor) __d = divisor; \ | |
c4e18497 | 144 | (((typeof(x))-1) > 0 || \ |
4f5901f5 NS |
145 | ((typeof(divisor))-1) > 0 || \ |
146 | (((__x) > 0) == ((__d) > 0))) ? \ | |
b6d86d3d GR |
147 | (((__x) + ((__d) / 2)) / (__d)) : \ |
148 | (((__x) - ((__d) / 2)) / (__d)); \ | |
9fe06081 DW |
149 | } \ |
150 | ) | |
f766093e JM |
151 | /* |
152 | * Same as above but for u64 dividends. divisor must be a 32-bit | |
153 | * number. | |
154 | */ | |
155 | #define DIV_ROUND_CLOSEST_ULL(x, divisor)( \ | |
156 | { \ | |
157 | typeof(divisor) __d = divisor; \ | |
158 | unsigned long long _tmp = (x) + (__d) / 2; \ | |
159 | do_div(_tmp, __d); \ | |
160 | _tmp; \ | |
161 | } \ | |
162 | ) | |
1da177e4 | 163 | |
9993bc63 SQ |
164 | /* |
165 | * Multiplies an integer by a fraction, while avoiding unnecessary | |
166 | * overflow or loss of precision. | |
167 | */ | |
168 | #define mult_frac(x, numer, denom)( \ | |
169 | { \ | |
170 | typeof(x) quot = (x) / (denom); \ | |
171 | typeof(x) rem = (x) % (denom); \ | |
172 | (quot * (numer)) + ((rem * (numer)) / (denom)); \ | |
173 | } \ | |
174 | ) | |
175 | ||
176 | ||
ca31e146 EGM |
177 | #define _RET_IP_ (unsigned long)__builtin_return_address(0) |
178 | #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) | |
179 | ||
72deb455 | 180 | #define sector_div(a, b) do_div(a, b) |
2da96acd | 181 | |
218e180e AM |
182 | /** |
183 | * upper_32_bits - return bits 32-63 of a number | |
184 | * @n: the number we're accessing | |
185 | * | |
186 | * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress | |
187 | * the "right shift count >= width of type" warning when that quantity is | |
188 | * 32-bits. | |
189 | */ | |
190 | #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) | |
191 | ||
204b885e JR |
192 | /** |
193 | * lower_32_bits - return bits 0-31 of a number | |
194 | * @n: the number we're accessing | |
195 | */ | |
196 | #define lower_32_bits(n) ((u32)(n)) | |
197 | ||
1da177e4 | 198 | struct completion; |
df2e71fb | 199 | struct pt_regs; |
200 | struct user; | |
1da177e4 | 201 | |
070cb065 UKK |
202 | #ifdef CONFIG_PREEMPT_VOLUNTARY |
203 | extern int _cond_resched(void); | |
204 | # define might_resched() _cond_resched() | |
205 | #else | |
206 | # define might_resched() do { } while (0) | |
207 | #endif | |
208 | ||
d902db1e | 209 | #ifdef CONFIG_DEBUG_ATOMIC_SLEEP |
568f1967 PZ |
210 | extern void ___might_sleep(const char *file, int line, int preempt_offset); |
211 | extern void __might_sleep(const char *file, int line, int preempt_offset); | |
212 | extern void __cant_sleep(const char *file, int line, int preempt_offset); | |
213 | ||
1da177e4 LT |
214 | /** |
215 | * might_sleep - annotation for functions that can sleep | |
216 | * | |
217 | * this macro will print a stack trace if it is executed in an atomic | |
218 | * context (spinlock, irq-handler, ...). | |
219 | * | |
220 | * This is a useful debugging help to be able to catch problems early and not | |
e20ec991 | 221 | * be bitten later when the calling function happens to sleep when it is not |
1da177e4 LT |
222 | * supposed to. |
223 | */ | |
f8cbd99b | 224 | # define might_sleep() \ |
e4aafea2 | 225 | do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) |
568f1967 PZ |
226 | /** |
227 | * cant_sleep - annotation for functions that cannot sleep | |
228 | * | |
229 | * this macro will print a stack trace if it is executed with preemption enabled | |
230 | */ | |
231 | # define cant_sleep() \ | |
232 | do { __cant_sleep(__FILE__, __LINE__, 0); } while (0) | |
00845eb9 | 233 | # define sched_annotate_sleep() (current->task_state_change = 0) |
1da177e4 | 234 | #else |
3427445a PZ |
235 | static inline void ___might_sleep(const char *file, int line, |
236 | int preempt_offset) { } | |
d894837f SK |
237 | static inline void __might_sleep(const char *file, int line, |
238 | int preempt_offset) { } | |
f8cbd99b | 239 | # define might_sleep() do { might_resched(); } while (0) |
568f1967 | 240 | # define cant_sleep() do { } while (0) |
1029a2b5 | 241 | # define sched_annotate_sleep() do { } while (0) |
1da177e4 LT |
242 | #endif |
243 | ||
368a5fa1 | 244 | #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) |
f8cbd99b | 245 | |
c8299cb6 MN |
246 | /** |
247 | * abs - return absolute value of an argument | |
8f57e4d9 MN |
248 | * @x: the value. If it is unsigned type, it is converted to signed type first. |
249 | * char is treated as if it was signed (regardless of whether it really is) | |
250 | * but the macro's return type is preserved as char. | |
c8299cb6 | 251 | * |
8f57e4d9 | 252 | * Return: an absolute value of x. |
71a90484 | 253 | */ |
8f57e4d9 MN |
254 | #define abs(x) __abs_choose_expr(x, long long, \ |
255 | __abs_choose_expr(x, long, \ | |
256 | __abs_choose_expr(x, int, \ | |
257 | __abs_choose_expr(x, short, \ | |
258 | __abs_choose_expr(x, char, \ | |
259 | __builtin_choose_expr( \ | |
260 | __builtin_types_compatible_p(typeof(x), char), \ | |
261 | (char)({ signed char __x = (x); __x<0?-__x:__x; }), \ | |
262 | ((void)0))))))) | |
263 | ||
264 | #define __abs_choose_expr(x, type, other) __builtin_choose_expr( \ | |
265 | __builtin_types_compatible_p(typeof(x), signed type) || \ | |
266 | __builtin_types_compatible_p(typeof(x), unsigned type), \ | |
267 | ({ signed type __x = (x); __x < 0 ? -__x : __x; }), other) | |
c8299cb6 | 268 | |
89770b0a DB |
269 | /** |
270 | * reciprocal_scale - "scale" a value into range [0, ep_ro) | |
271 | * @val: value | |
272 | * @ep_ro: right open interval endpoint | |
273 | * | |
274 | * Perform a "reciprocal multiplication" in order to "scale" a value into | |
e8c97af0 | 275 | * range [0, @ep_ro), where the upper interval endpoint is right-open. |
89770b0a | 276 | * This is useful, e.g. for accessing a index of an array containing |
e8c97af0 | 277 | * @ep_ro elements, for example. Think of it as sort of modulus, only that |
89770b0a DB |
278 | * the result isn't that of modulo. ;) Note that if initial input is a |
279 | * small value, then result will return 0. | |
280 | * | |
e8c97af0 | 281 | * Return: a result based on @val in interval [0, @ep_ro). |
89770b0a DB |
282 | */ |
283 | static inline u32 reciprocal_scale(u32 val, u32 ep_ro) | |
284 | { | |
285 | return (u32)(((u64) val * ep_ro) >> 32); | |
286 | } | |
287 | ||
386e7906 AL |
288 | #if defined(CONFIG_MMU) && \ |
289 | (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP)) | |
9ec23531 DH |
290 | #define might_fault() __might_fault(__FILE__, __LINE__) |
291 | void __might_fault(const char *file, int line); | |
3ee1afa3 | 292 | #else |
662bbcb2 | 293 | static inline void might_fault(void) { } |
3ee1afa3 NP |
294 | #endif |
295 | ||
e041c683 | 296 | extern struct atomic_notifier_head panic_notifier_list; |
c7ff0d9c | 297 | extern long (*panic_blink)(int state); |
9402c95f | 298 | __printf(1, 2) |
9af6528e | 299 | void panic(const char *fmt, ...) __noreturn __cold; |
ebc41f20 | 300 | void nmi_panic(struct pt_regs *regs, const char *msg); |
dd287796 AM |
301 | extern void oops_enter(void); |
302 | extern void oops_exit(void); | |
863a6049 | 303 | void print_oops_end_marker(void); |
dd287796 | 304 | extern int oops_may_print(void); |
9af6528e PZ |
305 | void do_exit(long error_code) __noreturn; |
306 | void complete_and_exit(struct completion *, long) __noreturn; | |
33ee3b2e | 307 | |
7a46ec0e KC |
308 | #ifdef CONFIG_ARCH_HAS_REFCOUNT |
309 | void refcount_error_report(struct pt_regs *regs, const char *err); | |
310 | #else | |
311 | static inline void refcount_error_report(struct pt_regs *regs, const char *err) | |
312 | { } | |
313 | #endif | |
314 | ||
33ee3b2e AD |
315 | /* Internal, do not use. */ |
316 | int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); | |
317 | int __must_check _kstrtol(const char *s, unsigned int base, long *res); | |
318 | ||
319 | int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); | |
320 | int __must_check kstrtoll(const char *s, unsigned int base, long long *res); | |
4c925d60 EZ |
321 | |
322 | /** | |
323 | * kstrtoul - convert a string to an unsigned long | |
324 | * @s: The start of the string. The string must be null-terminated, and may also | |
325 | * include a single newline before its terminating null. The first character | |
326 | * may also be a plus sign, but not a minus sign. | |
327 | * @base: The number base to use. The maximum supported base is 16. If base is | |
328 | * given as 0, then the base of the string is automatically detected with the | |
329 | * conventional semantics - If it begins with 0x the number will be parsed as a | |
330 | * hexadecimal (case insensitive), if it otherwise begins with 0, it will be | |
331 | * parsed as an octal number. Otherwise it will be parsed as a decimal. | |
332 | * @res: Where to write the result of the conversion on success. | |
333 | * | |
334 | * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. | |
335 | * Used as a replacement for the obsolete simple_strtoull. Return code must | |
336 | * be checked. | |
337 | */ | |
33ee3b2e AD |
338 | static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) |
339 | { | |
340 | /* | |
341 | * We want to shortcut function call, but | |
342 | * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. | |
343 | */ | |
344 | if (sizeof(unsigned long) == sizeof(unsigned long long) && | |
345 | __alignof__(unsigned long) == __alignof__(unsigned long long)) | |
346 | return kstrtoull(s, base, (unsigned long long *)res); | |
347 | else | |
348 | return _kstrtoul(s, base, res); | |
349 | } | |
350 | ||
4c925d60 EZ |
351 | /** |
352 | * kstrtol - convert a string to a long | |
353 | * @s: The start of the string. The string must be null-terminated, and may also | |
354 | * include a single newline before its terminating null. The first character | |
355 | * may also be a plus sign or a minus sign. | |
356 | * @base: The number base to use. The maximum supported base is 16. If base is | |
357 | * given as 0, then the base of the string is automatically detected with the | |
358 | * conventional semantics - If it begins with 0x the number will be parsed as a | |
359 | * hexadecimal (case insensitive), if it otherwise begins with 0, it will be | |
360 | * parsed as an octal number. Otherwise it will be parsed as a decimal. | |
361 | * @res: Where to write the result of the conversion on success. | |
362 | * | |
363 | * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. | |
364 | * Used as a replacement for the obsolete simple_strtoull. Return code must | |
365 | * be checked. | |
366 | */ | |
33ee3b2e AD |
367 | static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) |
368 | { | |
369 | /* | |
370 | * We want to shortcut function call, but | |
371 | * __builtin_types_compatible_p(long, long long) = 0. | |
372 | */ | |
373 | if (sizeof(long) == sizeof(long long) && | |
374 | __alignof__(long) == __alignof__(long long)) | |
375 | return kstrtoll(s, base, (long long *)res); | |
376 | else | |
377 | return _kstrtol(s, base, res); | |
378 | } | |
379 | ||
380 | int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); | |
381 | int __must_check kstrtoint(const char *s, unsigned int base, int *res); | |
382 | ||
383 | static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) | |
384 | { | |
385 | return kstrtoull(s, base, res); | |
386 | } | |
387 | ||
388 | static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) | |
389 | { | |
390 | return kstrtoll(s, base, res); | |
391 | } | |
392 | ||
393 | static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) | |
394 | { | |
395 | return kstrtouint(s, base, res); | |
396 | } | |
397 | ||
398 | static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) | |
399 | { | |
400 | return kstrtoint(s, base, res); | |
401 | } | |
402 | ||
403 | int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); | |
404 | int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); | |
405 | int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); | |
406 | int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); | |
ef951599 | 407 | int __must_check kstrtobool(const char *s, bool *res); |
33ee3b2e | 408 | |
c196e32a AD |
409 | int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); |
410 | int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); | |
411 | int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); | |
412 | int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); | |
413 | int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); | |
414 | int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); | |
415 | int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); | |
416 | int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); | |
417 | int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); | |
418 | int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); | |
ef951599 | 419 | int __must_check kstrtobool_from_user(const char __user *s, size_t count, bool *res); |
c196e32a AD |
420 | |
421 | static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) | |
422 | { | |
423 | return kstrtoull_from_user(s, count, base, res); | |
424 | } | |
425 | ||
426 | static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) | |
427 | { | |
428 | return kstrtoll_from_user(s, count, base, res); | |
429 | } | |
430 | ||
431 | static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) | |
432 | { | |
433 | return kstrtouint_from_user(s, count, base, res); | |
434 | } | |
435 | ||
436 | static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) | |
437 | { | |
438 | return kstrtoint_from_user(s, count, base, res); | |
439 | } | |
440 | ||
67d0a075 JP |
441 | /* Obsolete, do not use. Use kstrto<foo> instead */ |
442 | ||
1da177e4 LT |
443 | extern unsigned long simple_strtoul(const char *,char **,unsigned int); |
444 | extern long simple_strtol(const char *,char **,unsigned int); | |
445 | extern unsigned long long simple_strtoull(const char *,char **,unsigned int); | |
446 | extern long long simple_strtoll(const char *,char **,unsigned int); | |
33ee3b2e | 447 | |
d1be35cb AV |
448 | extern int num_to_str(char *buf, int size, |
449 | unsigned long long num, unsigned int width); | |
1ac101a5 | 450 | |
67d0a075 JP |
451 | /* lib/printf utilities */ |
452 | ||
b9075fa9 JP |
453 | extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); |
454 | extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); | |
455 | extern __printf(3, 4) | |
456 | int snprintf(char *buf, size_t size, const char *fmt, ...); | |
457 | extern __printf(3, 0) | |
458 | int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); | |
459 | extern __printf(3, 4) | |
460 | int scnprintf(char *buf, size_t size, const char *fmt, ...); | |
461 | extern __printf(3, 0) | |
462 | int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); | |
48a27055 | 463 | extern __printf(2, 3) __malloc |
b9075fa9 | 464 | char *kasprintf(gfp_t gfp, const char *fmt, ...); |
48a27055 | 465 | extern __printf(2, 0) __malloc |
8db14860 | 466 | char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); |
0a9df786 RV |
467 | extern __printf(2, 0) |
468 | const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list args); | |
1da177e4 | 469 | |
6061d949 JP |
470 | extern __scanf(2, 3) |
471 | int sscanf(const char *, const char *, ...); | |
472 | extern __scanf(2, 0) | |
473 | int vsscanf(const char *, const char *, va_list); | |
1da177e4 LT |
474 | |
475 | extern int get_option(char **str, int *pint); | |
476 | extern char *get_options(const char *str, int nints, int *ints); | |
d974ae37 | 477 | extern unsigned long long memparse(const char *ptr, char **retptr); |
6ccc72b8 | 478 | extern bool parse_option_str(const char *str, const char *option); |
f51b17c8 | 479 | extern char *next_arg(char *args, char **param, char **val); |
1da177e4 | 480 | |
5e376613 | 481 | extern int core_kernel_text(unsigned long addr); |
9fbcc57a | 482 | extern int init_kernel_text(unsigned long addr); |
cdbe61bf | 483 | extern int core_kernel_data(unsigned long addr); |
1da177e4 LT |
484 | extern int __kernel_text_address(unsigned long addr); |
485 | extern int kernel_text_address(unsigned long addr); | |
ab7476cf | 486 | extern int func_ptr_is_kernel_text(void *ptr); |
ab7476cf | 487 | |
9f615894 | 488 | u64 int_pow(u64 base, unsigned int exp); |
1da177e4 LT |
489 | unsigned long int_sqrt(unsigned long); |
490 | ||
47a36163 CM |
491 | #if BITS_PER_LONG < 64 |
492 | u32 int_sqrt64(u64 x); | |
493 | #else | |
494 | static inline u32 int_sqrt64(u64 x) | |
495 | { | |
496 | return (u32)int_sqrt(x); | |
497 | } | |
498 | #endif | |
499 | ||
1da177e4 LT |
500 | extern void bust_spinlocks(int yes); |
501 | extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ | |
aa727107 | 502 | extern int panic_timeout; |
81c9d43f | 503 | extern unsigned long panic_print; |
1da177e4 | 504 | extern int panic_on_oops; |
8da5adda | 505 | extern int panic_on_unrecovered_nmi; |
5211a242 | 506 | extern int panic_on_io_nmi; |
9e3961a0 | 507 | extern int panic_on_warn; |
088e9d25 | 508 | extern int sysctl_panic_on_rcu_stall; |
55af7796 | 509 | extern int sysctl_panic_on_stackoverflow; |
5375b708 HD |
510 | |
511 | extern bool crash_kexec_post_notifiers; | |
512 | ||
1717f209 HK |
513 | /* |
514 | * panic_cpu is used for synchronizing panic() and crash_kexec() execution. It | |
515 | * holds a CPU number which is executing panic() currently. A value of | |
516 | * PANIC_CPU_INVALID means no CPU has entered panic() or crash_kexec(). | |
517 | */ | |
518 | extern atomic_t panic_cpu; | |
519 | #define PANIC_CPU_INVALID -1 | |
520 | ||
5800dc3c JB |
521 | /* |
522 | * Only to be used by arch init code. If the user over-wrote the default | |
523 | * CONFIG_PANIC_TIMEOUT, honor it. | |
524 | */ | |
525 | static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout) | |
526 | { | |
527 | if (panic_timeout == arch_default_timeout) | |
528 | panic_timeout = timeout; | |
529 | } | |
1da177e4 | 530 | extern const char *print_tainted(void); |
373d4d09 RR |
531 | enum lockdep_ok { |
532 | LOCKDEP_STILL_OK, | |
533 | LOCKDEP_NOW_UNRELIABLE | |
534 | }; | |
535 | extern void add_taint(unsigned flag, enum lockdep_ok); | |
25ddbb18 AK |
536 | extern int test_taint(unsigned flag); |
537 | extern unsigned long get_taint(void); | |
b920de1b | 538 | extern int root_mountflags; |
1da177e4 | 539 | |
2ce802f6 TH |
540 | extern bool early_boot_irqs_disabled; |
541 | ||
69a78ff2 TG |
542 | /* |
543 | * Values used for system_state. Ordering of the states must not be changed | |
544 | * as code checks for <, <=, >, >= STATE. | |
545 | */ | |
1da177e4 LT |
546 | extern enum system_states { |
547 | SYSTEM_BOOTING, | |
69a78ff2 | 548 | SYSTEM_SCHEDULING, |
1da177e4 LT |
549 | SYSTEM_RUNNING, |
550 | SYSTEM_HALT, | |
551 | SYSTEM_POWER_OFF, | |
552 | SYSTEM_RESTART, | |
c1a957d1 | 553 | SYSTEM_SUSPEND, |
1da177e4 LT |
554 | } system_state; |
555 | ||
47d4b263 | 556 | /* This cannot be an enum because some may be used in assembly source. */ |
25ddbb18 AK |
557 | #define TAINT_PROPRIETARY_MODULE 0 |
558 | #define TAINT_FORCED_MODULE 1 | |
8c90487c | 559 | #define TAINT_CPU_OUT_OF_SPEC 2 |
25ddbb18 AK |
560 | #define TAINT_FORCED_RMMOD 3 |
561 | #define TAINT_MACHINE_CHECK 4 | |
562 | #define TAINT_BAD_PAGE 5 | |
563 | #define TAINT_USER 6 | |
564 | #define TAINT_DIE 7 | |
565 | #define TAINT_OVERRIDDEN_ACPI_TABLE 8 | |
566 | #define TAINT_WARN 9 | |
26e9a397 | 567 | #define TAINT_CRAP 10 |
92946bc7 | 568 | #define TAINT_FIRMWARE_WORKAROUND 11 |
2449b8ba | 569 | #define TAINT_OOT_MODULE 12 |
66cc69e3 | 570 | #define TAINT_UNSIGNED_MODULE 13 |
69361eef | 571 | #define TAINT_SOFTLOCKUP 14 |
c5f45465 | 572 | #define TAINT_LIVEPATCH 15 |
4efb442c | 573 | #define TAINT_AUX 16 |
bc4f2f54 KC |
574 | #define TAINT_RANDSTRUCT 17 |
575 | #define TAINT_FLAGS_COUNT 18 | |
7fd8329b PM |
576 | |
577 | struct taint_flag { | |
5eb7c0d0 LF |
578 | char c_true; /* character printed when tainted */ |
579 | char c_false; /* character printed when not tainted */ | |
7fd8329b PM |
580 | bool module; /* also show as a per-module taint flag */ |
581 | }; | |
582 | ||
583 | extern const struct taint_flag taint_flags[TAINT_FLAGS_COUNT]; | |
1da177e4 | 584 | |
3fc95772 HH |
585 | extern const char hex_asc[]; |
586 | #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] | |
587 | #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] | |
588 | ||
55036ba7 | 589 | static inline char *hex_byte_pack(char *buf, u8 byte) |
3fc95772 HH |
590 | { |
591 | *buf++ = hex_asc_hi(byte); | |
592 | *buf++ = hex_asc_lo(byte); | |
593 | return buf; | |
594 | } | |
99eaf3c4 | 595 | |
c26d436c AN |
596 | extern const char hex_asc_upper[]; |
597 | #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)] | |
598 | #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4] | |
599 | ||
600 | static inline char *hex_byte_pack_upper(char *buf, u8 byte) | |
601 | { | |
602 | *buf++ = hex_asc_upper_hi(byte); | |
603 | *buf++ = hex_asc_upper_lo(byte); | |
604 | return buf; | |
605 | } | |
606 | ||
90378889 | 607 | extern int hex_to_bin(char ch); |
b7804983 | 608 | extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); |
53d91c5c | 609 | extern char *bin2hex(char *dst, const void *src, size_t count); |
90378889 | 610 | |
a69f5edb | 611 | bool mac_pton(const char *s, u8 *mac); |
4cd5773a | 612 | |
526211bc IM |
613 | /* |
614 | * General tracing related utility functions - trace_printk(), | |
2002c258 SR |
615 | * tracing_on/tracing_off and tracing_start()/tracing_stop |
616 | * | |
617 | * Use tracing_on/tracing_off when you want to quickly turn on or off | |
618 | * tracing. It simply enables or disables the recording of the trace events. | |
156f5a78 | 619 | * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on |
2002c258 SR |
620 | * file, which gives a means for the kernel and userspace to interact. |
621 | * Place a tracing_off() in the kernel where you want tracing to end. | |
622 | * From user space, examine the trace, and then echo 1 > tracing_on | |
623 | * to continue tracing. | |
624 | * | |
625 | * tracing_stop/tracing_start has slightly more overhead. It is used | |
626 | * by things like suspend to ram where disabling the recording of the | |
627 | * trace is not enough, but tracing must actually stop because things | |
628 | * like calling smp_processor_id() may crash the system. | |
629 | * | |
630 | * Most likely, you want to use tracing_on/tracing_off. | |
526211bc | 631 | */ |
cecbca96 FW |
632 | |
633 | enum ftrace_dump_mode { | |
634 | DUMP_NONE, | |
635 | DUMP_ALL, | |
636 | DUMP_ORIG, | |
637 | }; | |
638 | ||
526211bc | 639 | #ifdef CONFIG_TRACING |
93d68e52 SR |
640 | void tracing_on(void); |
641 | void tracing_off(void); | |
642 | int tracing_is_on(void); | |
ad909e21 SRRH |
643 | void tracing_snapshot(void); |
644 | void tracing_snapshot_alloc(void); | |
93d68e52 | 645 | |
526211bc IM |
646 | extern void tracing_start(void); |
647 | extern void tracing_stop(void); | |
526211bc | 648 | |
b9075fa9 JP |
649 | static inline __printf(1, 2) |
650 | void ____trace_printk_check_format(const char *fmt, ...) | |
769b0441 FW |
651 | { |
652 | } | |
653 | #define __trace_printk_check_format(fmt, args...) \ | |
654 | do { \ | |
655 | if (0) \ | |
656 | ____trace_printk_check_format(fmt, ##args); \ | |
657 | } while (0) | |
658 | ||
526211bc IM |
659 | /** |
660 | * trace_printk - printf formatting in the ftrace buffer | |
661 | * @fmt: the printf format for printing | |
662 | * | |
e8c97af0 RD |
663 | * Note: __trace_printk is an internal function for trace_printk() and |
664 | * the @ip is passed in via the trace_printk() macro. | |
526211bc IM |
665 | * |
666 | * This function allows a kernel developer to debug fast path sections | |
667 | * that printk is not appropriate for. By scattering in various | |
668 | * printk like tracing in the code, a developer can quickly see | |
669 | * where problems are occurring. | |
670 | * | |
671 | * This is intended as a debugging tool for the developer only. | |
672 | * Please refrain from leaving trace_printks scattered around in | |
09ae7234 | 673 | * your code. (Extra memory is used for special buffers that are |
e8c97af0 | 674 | * allocated when trace_printk() is used.) |
9d3c752c | 675 | * |
8730662d | 676 | * A little optimization trick is done here. If there's only one |
9d3c752c SRRH |
677 | * argument, there's no need to scan the string for printf formats. |
678 | * The trace_puts() will suffice. But how can we take advantage of | |
679 | * using trace_puts() when trace_printk() has only one argument? | |
680 | * By stringifying the args and checking the size we can tell | |
681 | * whether or not there are args. __stringify((__VA_ARGS__)) will | |
682 | * turn into "()\0" with a size of 3 when there are no args, anything | |
683 | * else will be bigger. All we need to do is define a string to this, | |
684 | * and then take its size and compare to 3. If it's bigger, use | |
685 | * do_trace_printk() otherwise, optimize it to trace_puts(). Then just | |
686 | * let gcc optimize the rest. | |
526211bc | 687 | */ |
769b0441 | 688 | |
9d3c752c SRRH |
689 | #define trace_printk(fmt, ...) \ |
690 | do { \ | |
691 | char _______STR[] = __stringify((__VA_ARGS__)); \ | |
692 | if (sizeof(_______STR) > 3) \ | |
693 | do_trace_printk(fmt, ##__VA_ARGS__); \ | |
694 | else \ | |
695 | trace_puts(fmt); \ | |
696 | } while (0) | |
697 | ||
698 | #define do_trace_printk(fmt, args...) \ | |
769b0441 | 699 | do { \ |
3debb0a9 | 700 | static const char *trace_printk_fmt __used \ |
07d777fe SR |
701 | __attribute__((section("__trace_printk_fmt"))) = \ |
702 | __builtin_constant_p(fmt) ? fmt : NULL; \ | |
703 | \ | |
769b0441 | 704 | __trace_printk_check_format(fmt, ##args); \ |
48ead020 | 705 | \ |
07d777fe | 706 | if (__builtin_constant_p(fmt)) \ |
48ead020 | 707 | __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ |
07d777fe SR |
708 | else \ |
709 | __trace_printk(_THIS_IP_, fmt, ##args); \ | |
769b0441 FW |
710 | } while (0) |
711 | ||
b9075fa9 JP |
712 | extern __printf(2, 3) |
713 | int __trace_bprintk(unsigned long ip, const char *fmt, ...); | |
48ead020 | 714 | |
b9075fa9 JP |
715 | extern __printf(2, 3) |
716 | int __trace_printk(unsigned long ip, const char *fmt, ...); | |
769b0441 | 717 | |
09ae7234 SRRH |
718 | /** |
719 | * trace_puts - write a string into the ftrace buffer | |
720 | * @str: the string to record | |
721 | * | |
722 | * Note: __trace_bputs is an internal function for trace_puts and | |
723 | * the @ip is passed in via the trace_puts macro. | |
724 | * | |
725 | * This is similar to trace_printk() but is made for those really fast | |
e8c97af0 | 726 | * paths that a developer wants the least amount of "Heisenbug" effects, |
09ae7234 SRRH |
727 | * where the processing of the print format is still too much. |
728 | * | |
729 | * This function allows a kernel developer to debug fast path sections | |
730 | * that printk is not appropriate for. By scattering in various | |
731 | * printk like tracing in the code, a developer can quickly see | |
732 | * where problems are occurring. | |
733 | * | |
734 | * This is intended as a debugging tool for the developer only. | |
735 | * Please refrain from leaving trace_puts scattered around in | |
736 | * your code. (Extra memory is used for special buffers that are | |
e8c97af0 | 737 | * allocated when trace_puts() is used.) |
09ae7234 SRRH |
738 | * |
739 | * Returns: 0 if nothing was written, positive # if string was. | |
740 | * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used) | |
741 | */ | |
742 | ||
09ae7234 | 743 | #define trace_puts(str) ({ \ |
3debb0a9 | 744 | static const char *trace_printk_fmt __used \ |
09ae7234 SRRH |
745 | __attribute__((section("__trace_printk_fmt"))) = \ |
746 | __builtin_constant_p(str) ? str : NULL; \ | |
747 | \ | |
748 | if (__builtin_constant_p(str)) \ | |
749 | __trace_bputs(_THIS_IP_, trace_printk_fmt); \ | |
750 | else \ | |
751 | __trace_puts(_THIS_IP_, str, strlen(str)); \ | |
752 | }) | |
bcf312cf SR |
753 | extern int __trace_bputs(unsigned long ip, const char *str); |
754 | extern int __trace_puts(unsigned long ip, const char *str, int size); | |
09ae7234 | 755 | |
c142be8e | 756 | extern void trace_dump_stack(int skip); |
03889384 | 757 | |
48ead020 FW |
758 | /* |
759 | * The double __builtin_constant_p is because gcc will give us an error | |
760 | * if we try to allocate the static variable to fmt if it is not a | |
761 | * constant. Even with the outer if statement. | |
762 | */ | |
769b0441 FW |
763 | #define ftrace_vprintk(fmt, vargs) \ |
764 | do { \ | |
48ead020 | 765 | if (__builtin_constant_p(fmt)) { \ |
3debb0a9 | 766 | static const char *trace_printk_fmt __used \ |
48ead020 FW |
767 | __attribute__((section("__trace_printk_fmt"))) = \ |
768 | __builtin_constant_p(fmt) ? fmt : NULL; \ | |
7bffc23e | 769 | \ |
48ead020 FW |
770 | __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ |
771 | } else \ | |
772 | __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ | |
769b0441 FW |
773 | } while (0) |
774 | ||
8db14860 | 775 | extern __printf(2, 0) int |
48ead020 FW |
776 | __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); |
777 | ||
8db14860 | 778 | extern __printf(2, 0) int |
526211bc | 779 | __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); |
769b0441 | 780 | |
cecbca96 | 781 | extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); |
526211bc | 782 | #else |
526211bc IM |
783 | static inline void tracing_start(void) { } |
784 | static inline void tracing_stop(void) { } | |
e67bc51e | 785 | static inline void trace_dump_stack(int skip) { } |
93d68e52 SR |
786 | |
787 | static inline void tracing_on(void) { } | |
788 | static inline void tracing_off(void) { } | |
789 | static inline int tracing_is_on(void) { return 0; } | |
ad909e21 SRRH |
790 | static inline void tracing_snapshot(void) { } |
791 | static inline void tracing_snapshot_alloc(void) { } | |
93d68e52 | 792 | |
60efc15a MH |
793 | static inline __printf(1, 2) |
794 | int trace_printk(const char *fmt, ...) | |
526211bc IM |
795 | { |
796 | return 0; | |
797 | } | |
8db14860 | 798 | static __printf(1, 0) inline int |
526211bc IM |
799 | ftrace_vprintk(const char *fmt, va_list ap) |
800 | { | |
801 | return 0; | |
802 | } | |
cecbca96 | 803 | static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } |
769b0441 | 804 | #endif /* CONFIG_TRACING */ |
526211bc | 805 | |
1da177e4 | 806 | /* |
3c8ba0d6 KC |
807 | * min()/max()/clamp() macros must accomplish three things: |
808 | * | |
809 | * - avoid multiple evaluations of the arguments (so side-effects like | |
810 | * "x++" happen only once) when non-constant. | |
811 | * - perform strict type-checking (to generate warnings instead of | |
812 | * nasty runtime surprises). See the "unnecessary" pointer comparison | |
813 | * in __typecheck(). | |
814 | * - retain result as a constant expressions when called with only | |
815 | * constant expressions (to avoid tripping VLA warnings in stack | |
816 | * allocation usage). | |
1da177e4 | 817 | */ |
3c8ba0d6 KC |
818 | #define __typecheck(x, y) \ |
819 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) | |
820 | ||
821 | /* | |
822 | * This returns a constant expression while determining if an argument is | |
823 | * a constant expression, most importantly without evaluating the argument. | |
824 | * Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de> | |
825 | */ | |
826 | #define __is_constexpr(x) \ | |
827 | (sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8))) | |
828 | ||
829 | #define __no_side_effects(x, y) \ | |
830 | (__is_constexpr(x) && __is_constexpr(y)) | |
831 | ||
832 | #define __safe_cmp(x, y) \ | |
833 | (__typecheck(x, y) && __no_side_effects(x, y)) | |
834 | ||
835 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y)) | |
836 | ||
e9092d0d LT |
837 | #define __cmp_once(x, y, unique_x, unique_y, op) ({ \ |
838 | typeof(x) unique_x = (x); \ | |
839 | typeof(y) unique_y = (y); \ | |
840 | __cmp(unique_x, unique_y, op); }) | |
841 | ||
842 | #define __careful_cmp(x, y, op) \ | |
843 | __builtin_choose_expr(__safe_cmp(x, y), \ | |
844 | __cmp(x, y, op), \ | |
845 | __cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op)) | |
e8c97af0 RD |
846 | |
847 | /** | |
848 | * min - return minimum of two values of the same or compatible types | |
849 | * @x: first value | |
850 | * @y: second value | |
851 | */ | |
3c8ba0d6 | 852 | #define min(x, y) __careful_cmp(x, y, <) |
e8c97af0 RD |
853 | |
854 | /** | |
855 | * max - return maximum of two values of the same or compatible types | |
856 | * @x: first value | |
857 | * @y: second value | |
858 | */ | |
3c8ba0d6 | 859 | #define max(x, y) __careful_cmp(x, y, >) |
bdf4bbaa | 860 | |
e8c97af0 RD |
861 | /** |
862 | * min3 - return minimum of three values | |
863 | * @x: first value | |
864 | * @y: second value | |
865 | * @z: third value | |
866 | */ | |
2e1d06e1 | 867 | #define min3(x, y, z) min((typeof(x))min(x, y), z) |
e8c97af0 RD |
868 | |
869 | /** | |
870 | * max3 - return maximum of three values | |
871 | * @x: first value | |
872 | * @y: second value | |
873 | * @z: third value | |
874 | */ | |
2e1d06e1 | 875 | #define max3(x, y, z) max((typeof(x))max(x, y), z) |
f27c85c5 | 876 | |
c8bf1336 MP |
877 | /** |
878 | * min_not_zero - return the minimum that is _not_ zero, unless both are zero | |
879 | * @x: value1 | |
880 | * @y: value2 | |
881 | */ | |
882 | #define min_not_zero(x, y) ({ \ | |
883 | typeof(x) __x = (x); \ | |
884 | typeof(y) __y = (y); \ | |
885 | __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) | |
886 | ||
bdf4bbaa HH |
887 | /** |
888 | * clamp - return a value clamped to a given range with strict typechecking | |
889 | * @val: current value | |
2e1d06e1 MN |
890 | * @lo: lowest allowable value |
891 | * @hi: highest allowable value | |
bdf4bbaa | 892 | * |
e8c97af0 RD |
893 | * This macro does strict typechecking of @lo/@hi to make sure they are of the |
894 | * same type as @val. See the unnecessary pointer comparisons. | |
bdf4bbaa | 895 | */ |
2e1d06e1 | 896 | #define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi) |
1da177e4 LT |
897 | |
898 | /* | |
899 | * ..and if you can't take the strict | |
900 | * types, you can specify one yourself. | |
901 | * | |
bdf4bbaa HH |
902 | * Or not use min/max/clamp at all, of course. |
903 | */ | |
e8c97af0 RD |
904 | |
905 | /** | |
906 | * min_t - return minimum of two values, using the specified type | |
907 | * @type: data type to use | |
908 | * @x: first value | |
909 | * @y: second value | |
910 | */ | |
3c8ba0d6 | 911 | #define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <) |
589a9785 | 912 | |
e8c97af0 RD |
913 | /** |
914 | * max_t - return maximum of two values, using the specified type | |
915 | * @type: data type to use | |
916 | * @x: first value | |
917 | * @y: second value | |
918 | */ | |
3c8ba0d6 | 919 | #define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >) |
bdf4bbaa HH |
920 | |
921 | /** | |
922 | * clamp_t - return a value clamped to a given range using a given type | |
923 | * @type: the type of variable to use | |
924 | * @val: current value | |
c185b07f MN |
925 | * @lo: minimum allowable value |
926 | * @hi: maximum allowable value | |
bdf4bbaa HH |
927 | * |
928 | * This macro does no typechecking and uses temporary variables of type | |
e8c97af0 | 929 | * @type to make all the comparisons. |
1da177e4 | 930 | */ |
c185b07f | 931 | #define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi) |
1da177e4 | 932 | |
bdf4bbaa HH |
933 | /** |
934 | * clamp_val - return a value clamped to a given range using val's type | |
935 | * @val: current value | |
c185b07f MN |
936 | * @lo: minimum allowable value |
937 | * @hi: maximum allowable value | |
bdf4bbaa HH |
938 | * |
939 | * This macro does no typechecking and uses temporary variables of whatever | |
e8c97af0 RD |
940 | * type the input argument @val is. This is useful when @val is an unsigned |
941 | * type and @lo and @hi are literals that will otherwise be assigned a signed | |
bdf4bbaa HH |
942 | * integer type. |
943 | */ | |
c185b07f | 944 | #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi) |
1da177e4 | 945 | |
91f68b73 | 946 | |
e8c97af0 RD |
947 | /** |
948 | * swap - swap values of @a and @b | |
949 | * @a: first value | |
950 | * @b: second value | |
91f68b73 | 951 | */ |
ac7b9004 PZ |
952 | #define swap(a, b) \ |
953 | do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) | |
91f68b73 | 954 | |
cf14f27f AS |
955 | /* This counts to 12. Any more, it will return 13th argument. */ |
956 | #define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n | |
957 | #define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) | |
958 | ||
959 | #define __CONCAT(a, b) a ## b | |
960 | #define CONCATENATE(a, b) __CONCAT(a, b) | |
961 | ||
1da177e4 LT |
962 | /** |
963 | * container_of - cast a member of a structure out to the containing structure | |
1da177e4 LT |
964 | * @ptr: the pointer to the member. |
965 | * @type: the type of the container struct this is embedded in. | |
966 | * @member: the name of the member within the struct. | |
967 | * | |
968 | */ | |
c7acec71 IA |
969 | #define container_of(ptr, type, member) ({ \ |
970 | void *__mptr = (void *)(ptr); \ | |
971 | BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ | |
972 | !__same_type(*(ptr), void), \ | |
973 | "pointer type mismatch in container_of()"); \ | |
974 | ((type *)(__mptr - offsetof(type, member))); }) | |
1da177e4 | 975 | |
05e6557b N |
976 | /** |
977 | * container_of_safe - cast a member of a structure out to the containing structure | |
978 | * @ptr: the pointer to the member. | |
979 | * @type: the type of the container struct this is embedded in. | |
980 | * @member: the name of the member within the struct. | |
981 | * | |
982 | * If IS_ERR_OR_NULL(ptr), ptr is returned unchanged. | |
983 | */ | |
984 | #define container_of_safe(ptr, type, member) ({ \ | |
985 | void *__mptr = (void *)(ptr); \ | |
986 | BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ | |
987 | !__same_type(*(ptr), void), \ | |
988 | "pointer type mismatch in container_of()"); \ | |
227abcc6 | 989 | IS_ERR_OR_NULL(__mptr) ? ERR_CAST(__mptr) : \ |
05e6557b N |
990 | ((type *)(__mptr - offsetof(type, member))); }) |
991 | ||
b9d4f426 AL |
992 | /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ |
993 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD | |
994 | # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD | |
995 | #endif | |
9d00f92f | 996 | |
58f86cc8 | 997 | /* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */ |
28b8d0c8 GCM |
998 | #define VERIFY_OCTAL_PERMISSIONS(perms) \ |
999 | (BUILD_BUG_ON_ZERO((perms) < 0) + \ | |
1000 | BUILD_BUG_ON_ZERO((perms) > 0777) + \ | |
1001 | /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */ \ | |
1002 | BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) + \ | |
1003 | BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + \ | |
1004 | /* USER_WRITABLE >= GROUP_WRITABLE */ \ | |
1005 | BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) < (((perms) >> 3) & 2)) + \ | |
1006 | /* OTHER_WRITABLE? Generally considered a bad idea. */ \ | |
1007 | BUILD_BUG_ON_ZERO((perms) & 2) + \ | |
58f86cc8 | 1008 | (perms)) |
1da177e4 | 1009 | #endif |