xref: /linux-6.15/include/linux/kernel.h (revision 263a523d)
11da177e4SLinus Torvalds #ifndef _LINUX_KERNEL_H
21da177e4SLinus Torvalds #define _LINUX_KERNEL_H
31da177e4SLinus Torvalds 
4d8e5ddefSH. Peter Anvin #include <linux/sysinfo.h>
5d8e5ddefSH. Peter Anvin 
61da177e4SLinus Torvalds /*
71da177e4SLinus Torvalds  * 'kernel.h' contains some often-used function prototypes etc
81da177e4SLinus Torvalds  */
9a79ff731SAlexey Dobriyan #define __ALIGN_KERNEL(x, a)		__ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
10a79ff731SAlexey Dobriyan #define __ALIGN_KERNEL_MASK(x, mask)	(((x) + (mask)) & ~(mask))
111da177e4SLinus Torvalds 
121da177e4SLinus Torvalds #ifdef __KERNEL__
131da177e4SLinus Torvalds 
141da177e4SLinus Torvalds #include <stdarg.h>
151da177e4SLinus Torvalds #include <linux/linkage.h>
161da177e4SLinus Torvalds #include <linux/stddef.h>
171da177e4SLinus Torvalds #include <linux/types.h>
181da177e4SLinus Torvalds #include <linux/compiler.h>
191da177e4SLinus Torvalds #include <linux/bitops.h>
20f0d1b0b3SDavid Howells #include <linux/log2.h>
21e0deaff4SAndrew Morton #include <linux/typecheck.h>
22968ab183SLinus Torvalds #include <linux/printk.h>
23e9d376f0SJason Baron #include <linux/dynamic_debug.h>
241da177e4SLinus Torvalds #include <asm/byteorder.h>
251da177e4SLinus Torvalds 
264be929beSAlexey Dobriyan #define USHRT_MAX	((u16)(~0U))
274be929beSAlexey Dobriyan #define SHRT_MAX	((s16)(USHRT_MAX>>1))
284be929beSAlexey Dobriyan #define SHRT_MIN	((s16)(-SHRT_MAX - 1))
291da177e4SLinus Torvalds #define INT_MAX		((int)(~0U>>1))
301da177e4SLinus Torvalds #define INT_MIN		(-INT_MAX - 1)
311da177e4SLinus Torvalds #define UINT_MAX	(~0U)
321da177e4SLinus Torvalds #define LONG_MAX	((long)(~0UL>>1))
331da177e4SLinus Torvalds #define LONG_MIN	(-LONG_MAX - 1)
341da177e4SLinus Torvalds #define ULONG_MAX	(~0UL)
35111ebb6eSOGAWA Hirofumi #define LLONG_MAX	((long long)(~0ULL>>1))
36111ebb6eSOGAWA Hirofumi #define LLONG_MIN	(-LLONG_MAX - 1)
37111ebb6eSOGAWA Hirofumi #define ULLONG_MAX	(~0ULL)
38a3860c1cSXi Wang #define SIZE_MAX	(~(size_t)0)
391da177e4SLinus Torvalds 
401da177e4SLinus Torvalds #define STACK_MAGIC	0xdeadbeef
411da177e4SLinus Torvalds 
4244696908SDavid S. Miller #define REPEAT_BYTE(x)	((~0ul / 0xff) * (x))
4344696908SDavid S. Miller 
44a79ff731SAlexey Dobriyan #define ALIGN(x, a)		__ALIGN_KERNEL((x), (a))
459f93ff5bSAlexey Dobriyan #define __ALIGN_MASK(x, mask)	__ALIGN_KERNEL_MASK((x), (mask))
46a83308e6SMatthew Wilcox #define PTR_ALIGN(p, a)		((typeof(p))ALIGN((unsigned long)(p), (a)))
47f10db627SHerbert Xu #define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)
482ea58144SLinus Torvalds 
49c5e631cfSRusty Russell #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
50c5e631cfSRusty Russell 
519b3be9f9SYinghai Lu /*
529b3be9f9SYinghai Lu  * This looks more complex than it should be. But we need to
539b3be9f9SYinghai Lu  * get the type for the ~ right in round_down (it needs to be
549b3be9f9SYinghai Lu  * as wide as the result!), and we want to evaluate the macro
559b3be9f9SYinghai Lu  * arguments just once each.
569b3be9f9SYinghai Lu  */
579b3be9f9SYinghai Lu #define __round_mask(x, y) ((__typeof__(x))((y)-1))
589b3be9f9SYinghai Lu #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
599b3be9f9SYinghai Lu #define round_down(x, y) ((x) & ~__round_mask(x, y))
609b3be9f9SYinghai Lu 
614552d5dcSJan Beulich #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
62930631edSSteven Whitehouse #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
6336a26c69SNicholas Bellinger #define DIV_ROUND_UP_ULL(ll,d) \
6436a26c69SNicholas Bellinger 	({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
6536a26c69SNicholas Bellinger 
6636a26c69SNicholas Bellinger #if BITS_PER_LONG == 32
6736a26c69SNicholas Bellinger # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
6836a26c69SNicholas Bellinger #else
6936a26c69SNicholas Bellinger # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
7036a26c69SNicholas Bellinger #endif
71074e61ecSJames Morris 
72074e61ecSJames Morris /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
73b28efd54SEric Paris #define roundup(x, y) (					\
74b28efd54SEric Paris {							\
756070bf35STetsuo Handa 	const typeof(y) __y = y;			\
76b28efd54SEric Paris 	(((x) + (__y - 1)) / __y) * __y;		\
77b28efd54SEric Paris }							\
78b28efd54SEric Paris )
79686a0f3dSEric Paris #define rounddown(x, y) (				\
80686a0f3dSEric Paris {							\
81686a0f3dSEric Paris 	typeof(x) __x = (x);				\
82686a0f3dSEric Paris 	__x - (__x % (y));				\
83686a0f3dSEric Paris }							\
84686a0f3dSEric Paris )
85b6d86d3dSGuenter Roeck 
86b6d86d3dSGuenter Roeck /*
87b6d86d3dSGuenter Roeck  * Divide positive or negative dividend by positive divisor and round
88b6d86d3dSGuenter Roeck  * to closest integer. Result is undefined for negative divisors.
89b6d86d3dSGuenter Roeck  */
909fe06081SDarrick J. Wong #define DIV_ROUND_CLOSEST(x, divisor)(			\
919fe06081SDarrick J. Wong {							\
92b6d86d3dSGuenter Roeck 	typeof(x) __x = x;				\
93b6d86d3dSGuenter Roeck 	typeof(divisor) __d = divisor;			\
94*263a523dSGuenter Roeck 	(((typeof(x))-1) > 0 || (__x) > 0) ?		\
95b6d86d3dSGuenter Roeck 		(((__x) + ((__d) / 2)) / (__d)) :	\
96b6d86d3dSGuenter Roeck 		(((__x) - ((__d) / 2)) / (__d));	\
979fe06081SDarrick J. Wong }							\
989fe06081SDarrick J. Wong )
991da177e4SLinus Torvalds 
1009993bc63SSalman Qazi /*
1019993bc63SSalman Qazi  * Multiplies an integer by a fraction, while avoiding unnecessary
1029993bc63SSalman Qazi  * overflow or loss of precision.
1039993bc63SSalman Qazi  */
1049993bc63SSalman Qazi #define mult_frac(x, numer, denom)(			\
1059993bc63SSalman Qazi {							\
1069993bc63SSalman Qazi 	typeof(x) quot = (x) / (denom);			\
1079993bc63SSalman Qazi 	typeof(x) rem  = (x) % (denom);			\
1089993bc63SSalman Qazi 	(quot * (numer)) + ((rem * (numer)) / (denom));	\
1099993bc63SSalman Qazi }							\
1109993bc63SSalman Qazi )
1119993bc63SSalman Qazi 
1129993bc63SSalman Qazi 
113ca31e146SEduard - Gabriel Munteanu #define _RET_IP_		(unsigned long)__builtin_return_address(0)
114ca31e146SEduard - Gabriel Munteanu #define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
115ca31e146SEduard - Gabriel Munteanu 
11690c699a9SBartlomiej Zolnierkiewicz #ifdef CONFIG_LBDAF
1172da96acdSJens Axboe # include <asm/div64.h>
1182da96acdSJens Axboe # define sector_div(a, b) do_div(a, b)
1192da96acdSJens Axboe #else
1202da96acdSJens Axboe # define sector_div(n, b)( \
1212da96acdSJens Axboe { \
1222da96acdSJens Axboe 	int _res; \
1232da96acdSJens Axboe 	_res = (n) % (b); \
1242da96acdSJens Axboe 	(n) /= (b); \
1252da96acdSJens Axboe 	_res; \
1262da96acdSJens Axboe } \
1272da96acdSJens Axboe )
1282da96acdSJens Axboe #endif
1292da96acdSJens Axboe 
130218e180eSAndrew Morton /**
131218e180eSAndrew Morton  * upper_32_bits - return bits 32-63 of a number
132218e180eSAndrew Morton  * @n: the number we're accessing
133218e180eSAndrew Morton  *
134218e180eSAndrew Morton  * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
135218e180eSAndrew Morton  * the "right shift count >= width of type" warning when that quantity is
136218e180eSAndrew Morton  * 32-bits.
137218e180eSAndrew Morton  */
138218e180eSAndrew Morton #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
139218e180eSAndrew Morton 
140204b885eSJoerg Roedel /**
141204b885eSJoerg Roedel  * lower_32_bits - return bits 0-31 of a number
142204b885eSJoerg Roedel  * @n: the number we're accessing
143204b885eSJoerg Roedel  */
144204b885eSJoerg Roedel #define lower_32_bits(n) ((u32)(n))
145204b885eSJoerg Roedel 
1461da177e4SLinus Torvalds struct completion;
147df2e71fbS[email protected] struct pt_regs;
148df2e71fbS[email protected] struct user;
1491da177e4SLinus Torvalds 
150070cb065SUwe Kleine-König #ifdef CONFIG_PREEMPT_VOLUNTARY
151070cb065SUwe Kleine-König extern int _cond_resched(void);
152070cb065SUwe Kleine-König # define might_resched() _cond_resched()
153070cb065SUwe Kleine-König #else
154070cb065SUwe Kleine-König # define might_resched() do { } while (0)
155070cb065SUwe Kleine-König #endif
156070cb065SUwe Kleine-König 
157d902db1eSFrederic Weisbecker #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
158d894837fSSimon Kagstrom   void __might_sleep(const char *file, int line, int preempt_offset);
1591da177e4SLinus Torvalds /**
1601da177e4SLinus Torvalds  * might_sleep - annotation for functions that can sleep
1611da177e4SLinus Torvalds  *
1621da177e4SLinus Torvalds  * this macro will print a stack trace if it is executed in an atomic
1631da177e4SLinus Torvalds  * context (spinlock, irq-handler, ...).
1641da177e4SLinus Torvalds  *
1651da177e4SLinus Torvalds  * This is a useful debugging help to be able to catch problems early and not
166e20ec991SJim Cromie  * be bitten later when the calling function happens to sleep when it is not
1671da177e4SLinus Torvalds  * supposed to.
1681da177e4SLinus Torvalds  */
169f8cbd99bSIngo Molnar # define might_sleep() \
170e4aafea2SFrederic Weisbecker 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
171f8cbd99bSIngo Molnar #else
172d894837fSSimon Kagstrom   static inline void __might_sleep(const char *file, int line,
173d894837fSSimon Kagstrom 				   int preempt_offset) { }
174f8cbd99bSIngo Molnar # define might_sleep() do { might_resched(); } while (0)
175f8cbd99bSIngo Molnar #endif
176f8cbd99bSIngo Molnar 
177368a5fa1SHua Zhong #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
178f8cbd99bSIngo Molnar 
17971a90484SAndrew Morton /*
18071a90484SAndrew Morton  * abs() handles unsigned and signed longs, ints, shorts and chars.  For all
18171a90484SAndrew Morton  * input types abs() returns a signed long.
18271a90484SAndrew Morton  * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
18371a90484SAndrew Morton  * for those.
18471a90484SAndrew Morton  */
1851da177e4SLinus Torvalds #define abs(x) ({						\
18671a90484SAndrew Morton 		long ret;					\
18771a90484SAndrew Morton 		if (sizeof(x) == sizeof(long)) {		\
188a49c59c0SRolf Eike Beer 			long __x = (x);				\
18971a90484SAndrew Morton 			ret = (__x < 0) ? -__x : __x;		\
19071a90484SAndrew Morton 		} else {					\
19171a90484SAndrew Morton 			int __x = (x);				\
19271a90484SAndrew Morton 			ret = (__x < 0) ? -__x : __x;		\
19371a90484SAndrew Morton 		}						\
19471a90484SAndrew Morton 		ret;						\
1951da177e4SLinus Torvalds 	})
1961da177e4SLinus Torvalds 
197658716d1SBrian Behlendorf #define abs64(x) ({				\
198658716d1SBrian Behlendorf 		s64 __x = (x);			\
199658716d1SBrian Behlendorf 		(__x < 0) ? -__x : __x;		\
200658716d1SBrian Behlendorf 	})
201658716d1SBrian Behlendorf 
2023ee1afa3SNick Piggin #ifdef CONFIG_PROVE_LOCKING
2033ee1afa3SNick Piggin void might_fault(void);
2043ee1afa3SNick Piggin #else
2053ee1afa3SNick Piggin static inline void might_fault(void)
2063ee1afa3SNick Piggin {
2073ee1afa3SNick Piggin 	might_sleep();
2083ee1afa3SNick Piggin }
2093ee1afa3SNick Piggin #endif
2103ee1afa3SNick Piggin 
211e041c683SAlan Stern extern struct atomic_notifier_head panic_notifier_list;
212c7ff0d9cSTAMUKI Shoichi extern long (*panic_blink)(int state);
2139402c95fSJoe Perches __printf(1, 2)
2144da47859SJoe Perches void panic(const char *fmt, ...)
215ff2d8b19SJoe Perches 	__noreturn __cold;
216dd287796SAndrew Morton extern void oops_enter(void);
217dd287796SAndrew Morton extern void oops_exit(void);
218863a6049SAnton Blanchard void print_oops_end_marker(void);
219dd287796SAndrew Morton extern int oops_may_print(void);
2209402c95fSJoe Perches void do_exit(long error_code)
221ff2d8b19SJoe Perches 	__noreturn;
2229402c95fSJoe Perches void complete_and_exit(struct completion *, long)
223ff2d8b19SJoe Perches 	__noreturn;
22433ee3b2eSAlexey Dobriyan 
22533ee3b2eSAlexey Dobriyan /* Internal, do not use. */
22633ee3b2eSAlexey Dobriyan int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
22733ee3b2eSAlexey Dobriyan int __must_check _kstrtol(const char *s, unsigned int base, long *res);
22833ee3b2eSAlexey Dobriyan 
22933ee3b2eSAlexey Dobriyan int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
23033ee3b2eSAlexey Dobriyan int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
23133ee3b2eSAlexey Dobriyan static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
23233ee3b2eSAlexey Dobriyan {
23333ee3b2eSAlexey Dobriyan 	/*
23433ee3b2eSAlexey Dobriyan 	 * We want to shortcut function call, but
23533ee3b2eSAlexey Dobriyan 	 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
23633ee3b2eSAlexey Dobriyan 	 */
23733ee3b2eSAlexey Dobriyan 	if (sizeof(unsigned long) == sizeof(unsigned long long) &&
23833ee3b2eSAlexey Dobriyan 	    __alignof__(unsigned long) == __alignof__(unsigned long long))
23933ee3b2eSAlexey Dobriyan 		return kstrtoull(s, base, (unsigned long long *)res);
24033ee3b2eSAlexey Dobriyan 	else
24133ee3b2eSAlexey Dobriyan 		return _kstrtoul(s, base, res);
24233ee3b2eSAlexey Dobriyan }
24333ee3b2eSAlexey Dobriyan 
24433ee3b2eSAlexey Dobriyan static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
24533ee3b2eSAlexey Dobriyan {
24633ee3b2eSAlexey Dobriyan 	/*
24733ee3b2eSAlexey Dobriyan 	 * We want to shortcut function call, but
24833ee3b2eSAlexey Dobriyan 	 * __builtin_types_compatible_p(long, long long) = 0.
24933ee3b2eSAlexey Dobriyan 	 */
25033ee3b2eSAlexey Dobriyan 	if (sizeof(long) == sizeof(long long) &&
25133ee3b2eSAlexey Dobriyan 	    __alignof__(long) == __alignof__(long long))
25233ee3b2eSAlexey Dobriyan 		return kstrtoll(s, base, (long long *)res);
25333ee3b2eSAlexey Dobriyan 	else
25433ee3b2eSAlexey Dobriyan 		return _kstrtol(s, base, res);
25533ee3b2eSAlexey Dobriyan }
25633ee3b2eSAlexey Dobriyan 
25733ee3b2eSAlexey Dobriyan int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
25833ee3b2eSAlexey Dobriyan int __must_check kstrtoint(const char *s, unsigned int base, int *res);
25933ee3b2eSAlexey Dobriyan 
26033ee3b2eSAlexey Dobriyan static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
26133ee3b2eSAlexey Dobriyan {
26233ee3b2eSAlexey Dobriyan 	return kstrtoull(s, base, res);
26333ee3b2eSAlexey Dobriyan }
26433ee3b2eSAlexey Dobriyan 
26533ee3b2eSAlexey Dobriyan static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
26633ee3b2eSAlexey Dobriyan {
26733ee3b2eSAlexey Dobriyan 	return kstrtoll(s, base, res);
26833ee3b2eSAlexey Dobriyan }
26933ee3b2eSAlexey Dobriyan 
27033ee3b2eSAlexey Dobriyan static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
27133ee3b2eSAlexey Dobriyan {
27233ee3b2eSAlexey Dobriyan 	return kstrtouint(s, base, res);
27333ee3b2eSAlexey Dobriyan }
27433ee3b2eSAlexey Dobriyan 
27533ee3b2eSAlexey Dobriyan static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
27633ee3b2eSAlexey Dobriyan {
27733ee3b2eSAlexey Dobriyan 	return kstrtoint(s, base, res);
27833ee3b2eSAlexey Dobriyan }
27933ee3b2eSAlexey Dobriyan 
28033ee3b2eSAlexey Dobriyan int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
28133ee3b2eSAlexey Dobriyan int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
28233ee3b2eSAlexey Dobriyan int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
28333ee3b2eSAlexey Dobriyan int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
28433ee3b2eSAlexey Dobriyan 
285c196e32aSAlexey Dobriyan int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
286c196e32aSAlexey Dobriyan int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
287c196e32aSAlexey Dobriyan int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
288c196e32aSAlexey Dobriyan int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
289c196e32aSAlexey Dobriyan int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
290c196e32aSAlexey Dobriyan int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
291c196e32aSAlexey Dobriyan int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
292c196e32aSAlexey Dobriyan int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
293c196e32aSAlexey Dobriyan int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
294c196e32aSAlexey Dobriyan int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
295c196e32aSAlexey Dobriyan 
296c196e32aSAlexey Dobriyan static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
297c196e32aSAlexey Dobriyan {
298c196e32aSAlexey Dobriyan 	return kstrtoull_from_user(s, count, base, res);
299c196e32aSAlexey Dobriyan }
300c196e32aSAlexey Dobriyan 
301c196e32aSAlexey Dobriyan static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
302c196e32aSAlexey Dobriyan {
303c196e32aSAlexey Dobriyan 	return kstrtoll_from_user(s, count, base, res);
304c196e32aSAlexey Dobriyan }
305c196e32aSAlexey Dobriyan 
306c196e32aSAlexey Dobriyan static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
307c196e32aSAlexey Dobriyan {
308c196e32aSAlexey Dobriyan 	return kstrtouint_from_user(s, count, base, res);
309c196e32aSAlexey Dobriyan }
310c196e32aSAlexey Dobriyan 
311c196e32aSAlexey Dobriyan static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
312c196e32aSAlexey Dobriyan {
313c196e32aSAlexey Dobriyan 	return kstrtoint_from_user(s, count, base, res);
314c196e32aSAlexey Dobriyan }
315c196e32aSAlexey Dobriyan 
31667d0a075SJoe Perches /* Obsolete, do not use.  Use kstrto<foo> instead */
31767d0a075SJoe Perches 
3181da177e4SLinus Torvalds extern unsigned long simple_strtoul(const char *,char **,unsigned int);
3191da177e4SLinus Torvalds extern long simple_strtol(const char *,char **,unsigned int);
3201da177e4SLinus Torvalds extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
3211da177e4SLinus Torvalds extern long long simple_strtoll(const char *,char **,unsigned int);
32233ee3b2eSAlexey Dobriyan #define strict_strtoul	kstrtoul
32333ee3b2eSAlexey Dobriyan #define strict_strtol	kstrtol
32433ee3b2eSAlexey Dobriyan #define strict_strtoull	kstrtoull
32533ee3b2eSAlexey Dobriyan #define strict_strtoll	kstrtoll
32633ee3b2eSAlexey Dobriyan 
3271ac101a5SKAMEZAWA Hiroyuki extern int num_to_str(char *buf, int size, unsigned long long num);
3281ac101a5SKAMEZAWA Hiroyuki 
32967d0a075SJoe Perches /* lib/printf utilities */
33067d0a075SJoe Perches 
331b9075fa9SJoe Perches extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
332b9075fa9SJoe Perches extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
333b9075fa9SJoe Perches extern __printf(3, 4)
334b9075fa9SJoe Perches int snprintf(char *buf, size_t size, const char *fmt, ...);
335b9075fa9SJoe Perches extern __printf(3, 0)
336b9075fa9SJoe Perches int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
337b9075fa9SJoe Perches extern __printf(3, 4)
338b9075fa9SJoe Perches int scnprintf(char *buf, size_t size, const char *fmt, ...);
339b9075fa9SJoe Perches extern __printf(3, 0)
340b9075fa9SJoe Perches int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
341b9075fa9SJoe Perches extern __printf(2, 3)
342b9075fa9SJoe Perches char *kasprintf(gfp_t gfp, const char *fmt, ...);
34311443ec7SJeremy Fitzhardinge extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
3441da177e4SLinus Torvalds 
3456061d949SJoe Perches extern __scanf(2, 3)
3466061d949SJoe Perches int sscanf(const char *, const char *, ...);
3476061d949SJoe Perches extern __scanf(2, 0)
3486061d949SJoe Perches int vsscanf(const char *, const char *, va_list);
3491da177e4SLinus Torvalds 
3501da177e4SLinus Torvalds extern int get_option(char **str, int *pint);
3511da177e4SLinus Torvalds extern char *get_options(const char *str, int nints, int *ints);
352d974ae37SJeremy Fitzhardinge extern unsigned long long memparse(const char *ptr, char **retptr);
3531da177e4SLinus Torvalds 
3545e376613STrent Piepho extern int core_kernel_text(unsigned long addr);
355cdbe61bfSSteven Rostedt extern int core_kernel_data(unsigned long addr);
3561da177e4SLinus Torvalds extern int __kernel_text_address(unsigned long addr);
3571da177e4SLinus Torvalds extern int kernel_text_address(unsigned long addr);
358ab7476cfSArjan van de Ven extern int func_ptr_is_kernel_text(void *ptr);
359ab7476cfSArjan van de Ven 
36004a2e6a5SEric W. Biederman struct pid;
36104a2e6a5SEric W. Biederman extern struct pid *session_of_pgrp(struct pid *pgrp);
3621da177e4SLinus Torvalds 
3631da177e4SLinus Torvalds unsigned long int_sqrt(unsigned long);
3641da177e4SLinus Torvalds 
3651da177e4SLinus Torvalds extern void bust_spinlocks(int yes);
366e3e8a75dSKirill Korotaev extern void wake_up_klogd(void);
3671da177e4SLinus Torvalds extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
368aa727107SAdrian Bunk extern int panic_timeout;
3691da177e4SLinus Torvalds extern int panic_on_oops;
3708da5addaSDon Zickus extern int panic_on_unrecovered_nmi;
3715211a242SKurt Garloff extern int panic_on_io_nmi;
37255af7796SMitsuo Hayasaka extern int sysctl_panic_on_stackoverflow;
3731da177e4SLinus Torvalds extern const char *print_tainted(void);
37425ddbb18SAndi Kleen extern void add_taint(unsigned flag);
37525ddbb18SAndi Kleen extern int test_taint(unsigned flag);
37625ddbb18SAndi Kleen extern unsigned long get_taint(void);
377b920de1bSDavid Howells extern int root_mountflags;
3781da177e4SLinus Torvalds 
3792ce802f6STejun Heo extern bool early_boot_irqs_disabled;
3802ce802f6STejun Heo 
3811da177e4SLinus Torvalds /* Values used for system_state */
3821da177e4SLinus Torvalds extern enum system_states {
3831da177e4SLinus Torvalds 	SYSTEM_BOOTING,
3841da177e4SLinus Torvalds 	SYSTEM_RUNNING,
3851da177e4SLinus Torvalds 	SYSTEM_HALT,
3861da177e4SLinus Torvalds 	SYSTEM_POWER_OFF,
3871da177e4SLinus Torvalds 	SYSTEM_RESTART,
3881da177e4SLinus Torvalds } system_state;
3891da177e4SLinus Torvalds 
39025ddbb18SAndi Kleen #define TAINT_PROPRIETARY_MODULE	0
39125ddbb18SAndi Kleen #define TAINT_FORCED_MODULE		1
39225ddbb18SAndi Kleen #define TAINT_UNSAFE_SMP		2
39325ddbb18SAndi Kleen #define TAINT_FORCED_RMMOD		3
39425ddbb18SAndi Kleen #define TAINT_MACHINE_CHECK		4
39525ddbb18SAndi Kleen #define TAINT_BAD_PAGE			5
39625ddbb18SAndi Kleen #define TAINT_USER			6
39725ddbb18SAndi Kleen #define TAINT_DIE			7
39825ddbb18SAndi Kleen #define TAINT_OVERRIDDEN_ACPI_TABLE	8
39925ddbb18SAndi Kleen #define TAINT_WARN			9
40026e9a397SLinus Torvalds #define TAINT_CRAP			10
40192946bc7SBen Hutchings #define TAINT_FIRMWARE_WORKAROUND	11
4022449b8baSBen Hutchings #define TAINT_OOT_MODULE		12
4031da177e4SLinus Torvalds 
4043fc95772SHarvey Harrison extern const char hex_asc[];
4053fc95772SHarvey Harrison #define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
4063fc95772SHarvey Harrison #define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
4073fc95772SHarvey Harrison 
40855036ba7SAndy Shevchenko static inline char *hex_byte_pack(char *buf, u8 byte)
4093fc95772SHarvey Harrison {
4103fc95772SHarvey Harrison 	*buf++ = hex_asc_hi(byte);
4113fc95772SHarvey Harrison 	*buf++ = hex_asc_lo(byte);
4123fc95772SHarvey Harrison 	return buf;
4133fc95772SHarvey Harrison }
41499eaf3c4SRandy Dunlap 
41555036ba7SAndy Shevchenko static inline char * __deprecated pack_hex_byte(char *buf, u8 byte)
41655036ba7SAndy Shevchenko {
41755036ba7SAndy Shevchenko 	return hex_byte_pack(buf, byte);
41855036ba7SAndy Shevchenko }
41955036ba7SAndy Shevchenko 
42090378889SAndy Shevchenko extern int hex_to_bin(char ch);
421b7804983SMimi Zohar extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
42290378889SAndy Shevchenko 
4238a64f336SJoe Perches /*
424526211bcSIngo Molnar  * General tracing related utility functions - trace_printk(),
4252002c258SSteven Rostedt  * tracing_on/tracing_off and tracing_start()/tracing_stop
4262002c258SSteven Rostedt  *
4272002c258SSteven Rostedt  * Use tracing_on/tracing_off when you want to quickly turn on or off
4282002c258SSteven Rostedt  * tracing. It simply enables or disables the recording of the trace events.
429156f5a78SGeunSik Lim  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
4302002c258SSteven Rostedt  * file, which gives a means for the kernel and userspace to interact.
4312002c258SSteven Rostedt  * Place a tracing_off() in the kernel where you want tracing to end.
4322002c258SSteven Rostedt  * From user space, examine the trace, and then echo 1 > tracing_on
4332002c258SSteven Rostedt  * to continue tracing.
4342002c258SSteven Rostedt  *
4352002c258SSteven Rostedt  * tracing_stop/tracing_start has slightly more overhead. It is used
4362002c258SSteven Rostedt  * by things like suspend to ram where disabling the recording of the
4372002c258SSteven Rostedt  * trace is not enough, but tracing must actually stop because things
4382002c258SSteven Rostedt  * like calling smp_processor_id() may crash the system.
4392002c258SSteven Rostedt  *
4402002c258SSteven Rostedt  * Most likely, you want to use tracing_on/tracing_off.
441526211bcSIngo Molnar  */
4422002c258SSteven Rostedt #ifdef CONFIG_RING_BUFFER
4432002c258SSteven Rostedt /* trace_off_permanent stops recording with no way to bring it back */
4442002c258SSteven Rostedt void tracing_off_permanent(void);
4452002c258SSteven Rostedt #else
4462002c258SSteven Rostedt static inline void tracing_off_permanent(void) { }
4472002c258SSteven Rostedt #endif
448cecbca96SFrederic Weisbecker 
449cecbca96SFrederic Weisbecker enum ftrace_dump_mode {
450cecbca96SFrederic Weisbecker 	DUMP_NONE,
451cecbca96SFrederic Weisbecker 	DUMP_ALL,
452cecbca96SFrederic Weisbecker 	DUMP_ORIG,
453cecbca96SFrederic Weisbecker };
454cecbca96SFrederic Weisbecker 
455526211bcSIngo Molnar #ifdef CONFIG_TRACING
45693d68e52SSteven Rostedt void tracing_on(void);
45793d68e52SSteven Rostedt void tracing_off(void);
45893d68e52SSteven Rostedt int tracing_is_on(void);
45993d68e52SSteven Rostedt 
460526211bcSIngo Molnar extern void tracing_start(void);
461526211bcSIngo Molnar extern void tracing_stop(void);
462526211bcSIngo Molnar extern void ftrace_off_permanent(void);
463526211bcSIngo Molnar 
464b9075fa9SJoe Perches static inline __printf(1, 2)
465b9075fa9SJoe Perches void ____trace_printk_check_format(const char *fmt, ...)
466769b0441SFrederic Weisbecker {
467769b0441SFrederic Weisbecker }
468769b0441SFrederic Weisbecker #define __trace_printk_check_format(fmt, args...)			\
469769b0441SFrederic Weisbecker do {									\
470769b0441SFrederic Weisbecker 	if (0)								\
471769b0441SFrederic Weisbecker 		____trace_printk_check_format(fmt, ##args);		\
472769b0441SFrederic Weisbecker } while (0)
473769b0441SFrederic Weisbecker 
474526211bcSIngo Molnar /**
475526211bcSIngo Molnar  * trace_printk - printf formatting in the ftrace buffer
476526211bcSIngo Molnar  * @fmt: the printf format for printing
477526211bcSIngo Molnar  *
478526211bcSIngo Molnar  * Note: __trace_printk is an internal function for trace_printk and
479526211bcSIngo Molnar  *       the @ip is passed in via the trace_printk macro.
480526211bcSIngo Molnar  *
481526211bcSIngo Molnar  * This function allows a kernel developer to debug fast path sections
482526211bcSIngo Molnar  * that printk is not appropriate for. By scattering in various
483526211bcSIngo Molnar  * printk like tracing in the code, a developer can quickly see
484526211bcSIngo Molnar  * where problems are occurring.
485526211bcSIngo Molnar  *
486526211bcSIngo Molnar  * This is intended as a debugging tool for the developer only.
487526211bcSIngo Molnar  * Please refrain from leaving trace_printks scattered around in
488526211bcSIngo Molnar  * your code.
489526211bcSIngo Molnar  */
490769b0441SFrederic Weisbecker 
491769b0441SFrederic Weisbecker #define trace_printk(fmt, args...)					\
492769b0441SFrederic Weisbecker do {									\
49348ead020SFrederic Weisbecker 	static const char *trace_printk_fmt				\
49448ead020SFrederic Weisbecker 		__attribute__((section("__trace_printk_fmt"))) =	\
49548ead020SFrederic Weisbecker 		__builtin_constant_p(fmt) ? fmt : NULL;			\
49648ead020SFrederic Weisbecker 									\
49707d777feSSteven Rostedt 	__trace_printk_check_format(fmt, ##args);			\
49807d777feSSteven Rostedt 									\
49907d777feSSteven Rostedt 	if (__builtin_constant_p(fmt))					\
50048ead020SFrederic Weisbecker 		__trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);	\
50107d777feSSteven Rostedt 	else								\
50248ead020SFrederic Weisbecker 		__trace_printk(_THIS_IP_, fmt, ##args);			\
503769b0441SFrederic Weisbecker } while (0)
504769b0441SFrederic Weisbecker 
505b9075fa9SJoe Perches extern __printf(2, 3)
506b9075fa9SJoe Perches int __trace_bprintk(unsigned long ip, const char *fmt, ...);
50748ead020SFrederic Weisbecker 
508b9075fa9SJoe Perches extern __printf(2, 3)
509b9075fa9SJoe Perches int __trace_printk(unsigned long ip, const char *fmt, ...);
510769b0441SFrederic Weisbecker 
51103889384SSteven Rostedt extern void trace_dump_stack(void);
51203889384SSteven Rostedt 
51348ead020SFrederic Weisbecker /*
51448ead020SFrederic Weisbecker  * The double __builtin_constant_p is because gcc will give us an error
51548ead020SFrederic Weisbecker  * if we try to allocate the static variable to fmt if it is not a
51648ead020SFrederic Weisbecker  * constant. Even with the outer if statement.
51748ead020SFrederic Weisbecker  */
518769b0441SFrederic Weisbecker #define ftrace_vprintk(fmt, vargs)					\
519769b0441SFrederic Weisbecker do {									\
52048ead020SFrederic Weisbecker 	if (__builtin_constant_p(fmt)) {				\
521769b0441SFrederic Weisbecker 		static const char *trace_printk_fmt			\
52248ead020SFrederic Weisbecker 		  __attribute__((section("__trace_printk_fmt"))) =	\
52348ead020SFrederic Weisbecker 			__builtin_constant_p(fmt) ? fmt : NULL;		\
5247bffc23eSIngo Molnar 									\
52548ead020SFrederic Weisbecker 		__ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);	\
52648ead020SFrederic Weisbecker 	} else								\
52748ead020SFrederic Weisbecker 		__ftrace_vprintk(_THIS_IP_, fmt, vargs);		\
528769b0441SFrederic Weisbecker } while (0)
529769b0441SFrederic Weisbecker 
530526211bcSIngo Molnar extern int
53148ead020SFrederic Weisbecker __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
53248ead020SFrederic Weisbecker 
53348ead020SFrederic Weisbecker extern int
534526211bcSIngo Molnar __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
535769b0441SFrederic Weisbecker 
536cecbca96SFrederic Weisbecker extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
537526211bcSIngo Molnar #else
538b9075fa9SJoe Perches static inline __printf(1, 2)
539b9075fa9SJoe Perches int trace_printk(const char *fmt, ...);
540526211bcSIngo Molnar 
541526211bcSIngo Molnar static inline void tracing_start(void) { }
542526211bcSIngo Molnar static inline void tracing_stop(void) { }
543526211bcSIngo Molnar static inline void ftrace_off_permanent(void) { }
544e36c5458SSteven Rostedt static inline void trace_dump_stack(void) { }
54593d68e52SSteven Rostedt 
54693d68e52SSteven Rostedt static inline void tracing_on(void) { }
54793d68e52SSteven Rostedt static inline void tracing_off(void) { }
54893d68e52SSteven Rostedt static inline int tracing_is_on(void) { return 0; }
54993d68e52SSteven Rostedt 
550526211bcSIngo Molnar static inline int
551526211bcSIngo Molnar trace_printk(const char *fmt, ...)
552526211bcSIngo Molnar {
553526211bcSIngo Molnar 	return 0;
554526211bcSIngo Molnar }
555526211bcSIngo Molnar static inline int
556526211bcSIngo Molnar ftrace_vprintk(const char *fmt, va_list ap)
557526211bcSIngo Molnar {
558526211bcSIngo Molnar 	return 0;
559526211bcSIngo Molnar }
560cecbca96SFrederic Weisbecker static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
561769b0441SFrederic Weisbecker #endif /* CONFIG_TRACING */
562526211bcSIngo Molnar 
563526211bcSIngo Molnar /*
564bdf4bbaaSHarvey Harrison  * min()/max()/clamp() macros that also do
5651da177e4SLinus Torvalds  * strict type-checking.. See the
5661da177e4SLinus Torvalds  * "unnecessary" pointer comparison.
5671da177e4SLinus Torvalds  */
5681da177e4SLinus Torvalds #define min(x, y) ({				\
569bdf4bbaaSHarvey Harrison 	typeof(x) _min1 = (x);			\
570bdf4bbaaSHarvey Harrison 	typeof(y) _min2 = (y);			\
571bdf4bbaaSHarvey Harrison 	(void) (&_min1 == &_min2);		\
572bdf4bbaaSHarvey Harrison 	_min1 < _min2 ? _min1 : _min2; })
5731da177e4SLinus Torvalds 
5741da177e4SLinus Torvalds #define max(x, y) ({				\
575bdf4bbaaSHarvey Harrison 	typeof(x) _max1 = (x);			\
576bdf4bbaaSHarvey Harrison 	typeof(y) _max2 = (y);			\
577bdf4bbaaSHarvey Harrison 	(void) (&_max1 == &_max2);		\
578bdf4bbaaSHarvey Harrison 	_max1 > _max2 ? _max1 : _max2; })
579bdf4bbaaSHarvey Harrison 
580f27c85c5SHagen Paul Pfeifer #define min3(x, y, z) ({			\
581f27c85c5SHagen Paul Pfeifer 	typeof(x) _min1 = (x);			\
582f27c85c5SHagen Paul Pfeifer 	typeof(y) _min2 = (y);			\
583f27c85c5SHagen Paul Pfeifer 	typeof(z) _min3 = (z);			\
584f27c85c5SHagen Paul Pfeifer 	(void) (&_min1 == &_min2);		\
585f27c85c5SHagen Paul Pfeifer 	(void) (&_min1 == &_min3);		\
586f27c85c5SHagen Paul Pfeifer 	_min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
587f27c85c5SHagen Paul Pfeifer 		(_min2 < _min3 ? _min2 : _min3); })
588f27c85c5SHagen Paul Pfeifer 
589f27c85c5SHagen Paul Pfeifer #define max3(x, y, z) ({			\
590f27c85c5SHagen Paul Pfeifer 	typeof(x) _max1 = (x);			\
591f27c85c5SHagen Paul Pfeifer 	typeof(y) _max2 = (y);			\
592f27c85c5SHagen Paul Pfeifer 	typeof(z) _max3 = (z);			\
593f27c85c5SHagen Paul Pfeifer 	(void) (&_max1 == &_max2);		\
594f27c85c5SHagen Paul Pfeifer 	(void) (&_max1 == &_max3);		\
595f27c85c5SHagen Paul Pfeifer 	_max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
596f27c85c5SHagen Paul Pfeifer 		(_max2 > _max3 ? _max2 : _max3); })
597f27c85c5SHagen Paul Pfeifer 
598bdf4bbaaSHarvey Harrison /**
599c8bf1336SMartin K. Petersen  * min_not_zero - return the minimum that is _not_ zero, unless both are zero
600c8bf1336SMartin K. Petersen  * @x: value1
601c8bf1336SMartin K. Petersen  * @y: value2
602c8bf1336SMartin K. Petersen  */
603c8bf1336SMartin K. Petersen #define min_not_zero(x, y) ({			\
604c8bf1336SMartin K. Petersen 	typeof(x) __x = (x);			\
605c8bf1336SMartin K. Petersen 	typeof(y) __y = (y);			\
606c8bf1336SMartin K. Petersen 	__x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
607c8bf1336SMartin K. Petersen 
608c8bf1336SMartin K. Petersen /**
609bdf4bbaaSHarvey Harrison  * clamp - return a value clamped to a given range with strict typechecking
610bdf4bbaaSHarvey Harrison  * @val: current value
611bdf4bbaaSHarvey Harrison  * @min: minimum allowable value
612bdf4bbaaSHarvey Harrison  * @max: maximum allowable value
613bdf4bbaaSHarvey Harrison  *
614bdf4bbaaSHarvey Harrison  * This macro does strict typechecking of min/max to make sure they are of the
615bdf4bbaaSHarvey Harrison  * same type as val.  See the unnecessary pointer comparisons.
616bdf4bbaaSHarvey Harrison  */
617bdf4bbaaSHarvey Harrison #define clamp(val, min, max) ({			\
618bdf4bbaaSHarvey Harrison 	typeof(val) __val = (val);		\
619bdf4bbaaSHarvey Harrison 	typeof(min) __min = (min);		\
620bdf4bbaaSHarvey Harrison 	typeof(max) __max = (max);		\
621bdf4bbaaSHarvey Harrison 	(void) (&__val == &__min);		\
622bdf4bbaaSHarvey Harrison 	(void) (&__val == &__max);		\
623bdf4bbaaSHarvey Harrison 	__val = __val < __min ? __min: __val;	\
624bdf4bbaaSHarvey Harrison 	__val > __max ? __max: __val; })
6251da177e4SLinus Torvalds 
6261da177e4SLinus Torvalds /*
6271da177e4SLinus Torvalds  * ..and if you can't take the strict
6281da177e4SLinus Torvalds  * types, you can specify one yourself.
6291da177e4SLinus Torvalds  *
630bdf4bbaaSHarvey Harrison  * Or not use min/max/clamp at all, of course.
6311da177e4SLinus Torvalds  */
632bdf4bbaaSHarvey Harrison #define min_t(type, x, y) ({			\
633bdf4bbaaSHarvey Harrison 	type __min1 = (x);			\
634bdf4bbaaSHarvey Harrison 	type __min2 = (y);			\
635bdf4bbaaSHarvey Harrison 	__min1 < __min2 ? __min1: __min2; })
6361da177e4SLinus Torvalds 
637bdf4bbaaSHarvey Harrison #define max_t(type, x, y) ({			\
638bdf4bbaaSHarvey Harrison 	type __max1 = (x);			\
639bdf4bbaaSHarvey Harrison 	type __max2 = (y);			\
640bdf4bbaaSHarvey Harrison 	__max1 > __max2 ? __max1: __max2; })
641bdf4bbaaSHarvey Harrison 
642bdf4bbaaSHarvey Harrison /**
643bdf4bbaaSHarvey Harrison  * clamp_t - return a value clamped to a given range using a given type
644bdf4bbaaSHarvey Harrison  * @type: the type of variable to use
645bdf4bbaaSHarvey Harrison  * @val: current value
646bdf4bbaaSHarvey Harrison  * @min: minimum allowable value
647bdf4bbaaSHarvey Harrison  * @max: maximum allowable value
648bdf4bbaaSHarvey Harrison  *
649bdf4bbaaSHarvey Harrison  * This macro does no typechecking and uses temporary variables of type
650bdf4bbaaSHarvey Harrison  * 'type' to make all the comparisons.
651bdf4bbaaSHarvey Harrison  */
652bdf4bbaaSHarvey Harrison #define clamp_t(type, val, min, max) ({		\
653bdf4bbaaSHarvey Harrison 	type __val = (val);			\
654bdf4bbaaSHarvey Harrison 	type __min = (min);			\
655bdf4bbaaSHarvey Harrison 	type __max = (max);			\
656bdf4bbaaSHarvey Harrison 	__val = __val < __min ? __min: __val;	\
657bdf4bbaaSHarvey Harrison 	__val > __max ? __max: __val; })
658bdf4bbaaSHarvey Harrison 
659bdf4bbaaSHarvey Harrison /**
660bdf4bbaaSHarvey Harrison  * clamp_val - return a value clamped to a given range using val's type
661bdf4bbaaSHarvey Harrison  * @val: current value
662bdf4bbaaSHarvey Harrison  * @min: minimum allowable value
663bdf4bbaaSHarvey Harrison  * @max: maximum allowable value
664bdf4bbaaSHarvey Harrison  *
665bdf4bbaaSHarvey Harrison  * This macro does no typechecking and uses temporary variables of whatever
666bdf4bbaaSHarvey Harrison  * type the input argument 'val' is.  This is useful when val is an unsigned
667bdf4bbaaSHarvey Harrison  * type and min and max are literals that will otherwise be assigned a signed
668bdf4bbaaSHarvey Harrison  * integer type.
669bdf4bbaaSHarvey Harrison  */
670bdf4bbaaSHarvey Harrison #define clamp_val(val, min, max) ({		\
671bdf4bbaaSHarvey Harrison 	typeof(val) __val = (val);		\
672bdf4bbaaSHarvey Harrison 	typeof(val) __min = (min);		\
673bdf4bbaaSHarvey Harrison 	typeof(val) __max = (max);		\
674bdf4bbaaSHarvey Harrison 	__val = __val < __min ? __min: __val;	\
675bdf4bbaaSHarvey Harrison 	__val > __max ? __max: __val; })
6761da177e4SLinus Torvalds 
67791f68b73SWu Fengguang 
67891f68b73SWu Fengguang /*
67991f68b73SWu Fengguang  * swap - swap value of @a and @b
68091f68b73SWu Fengguang  */
681ac7b9004SPeter Zijlstra #define swap(a, b) \
682ac7b9004SPeter Zijlstra 	do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
68391f68b73SWu Fengguang 
6841da177e4SLinus Torvalds /**
6851da177e4SLinus Torvalds  * container_of - cast a member of a structure out to the containing structure
6861da177e4SLinus Torvalds  * @ptr:	the pointer to the member.
6871da177e4SLinus Torvalds  * @type:	the type of the container struct this is embedded in.
6881da177e4SLinus Torvalds  * @member:	the name of the member within the struct.
6891da177e4SLinus Torvalds  *
6901da177e4SLinus Torvalds  */
6911da177e4SLinus Torvalds #define container_of(ptr, type, member) ({			\
6921da177e4SLinus Torvalds 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
6931da177e4SLinus Torvalds 	(type *)( (char *)__mptr - offsetof(type,member) );})
6941da177e4SLinus Torvalds 
695b9d4f426SArnaud Lacombe /* Trap pasters of __FUNCTION__ at compile-time */
696b9d4f426SArnaud Lacombe #define __FUNCTION__ (__func__)
697b9d4f426SArnaud Lacombe 
698b9d4f426SArnaud Lacombe /* This helps us to avoid #ifdef CONFIG_NUMA */
699b9d4f426SArnaud Lacombe #ifdef CONFIG_NUMA
700b9d4f426SArnaud Lacombe #define NUMA_BUILD 1
701b9d4f426SArnaud Lacombe #else
702b9d4f426SArnaud Lacombe #define NUMA_BUILD 0
703b9d4f426SArnaud Lacombe #endif
704b9d4f426SArnaud Lacombe 
705b9d4f426SArnaud Lacombe /* This helps us avoid #ifdef CONFIG_COMPACTION */
706b9d4f426SArnaud Lacombe #ifdef CONFIG_COMPACTION
707b9d4f426SArnaud Lacombe #define COMPACTION_BUILD 1
708b9d4f426SArnaud Lacombe #else
709b9d4f426SArnaud Lacombe #define COMPACTION_BUILD 0
710b9d4f426SArnaud Lacombe #endif
711b9d4f426SArnaud Lacombe 
712b9d4f426SArnaud Lacombe /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
713b9d4f426SArnaud Lacombe #ifdef CONFIG_FTRACE_MCOUNT_RECORD
714b9d4f426SArnaud Lacombe # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
715b9d4f426SArnaud Lacombe #endif
7169d00f92fSWANG Cong 
7179d00f92fSWANG Cong extern int do_sysinfo(struct sysinfo *info);
7189d00f92fSWANG Cong 
7199d00f92fSWANG Cong #endif /* __KERNEL__ */
7209d00f92fSWANG Cong 
7211da177e4SLinus Torvalds #endif
722