xref: /linux-6.15/include/linux/kernel.h (revision 1399ff86)
11da177e4SLinus Torvalds #ifndef _LINUX_KERNEL_H
21da177e4SLinus Torvalds #define _LINUX_KERNEL_H
31da177e4SLinus Torvalds 
41da177e4SLinus Torvalds /*
51da177e4SLinus Torvalds  * 'kernel.h' contains some often-used function prototypes etc
61da177e4SLinus Torvalds  */
7a79ff731SAlexey Dobriyan #define __ALIGN_KERNEL(x, a)		__ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
8a79ff731SAlexey Dobriyan #define __ALIGN_KERNEL_MASK(x, mask)	(((x) + (mask)) & ~(mask))
91da177e4SLinus Torvalds 
101da177e4SLinus Torvalds #ifdef __KERNEL__
111da177e4SLinus Torvalds 
121da177e4SLinus Torvalds #include <stdarg.h>
131da177e4SLinus Torvalds #include <linux/linkage.h>
141da177e4SLinus Torvalds #include <linux/stddef.h>
151da177e4SLinus Torvalds #include <linux/types.h>
161da177e4SLinus Torvalds #include <linux/compiler.h>
171da177e4SLinus Torvalds #include <linux/bitops.h>
18f0d1b0b3SDavid Howells #include <linux/log2.h>
19e0deaff4SAndrew Morton #include <linux/typecheck.h>
20968ab183SLinus Torvalds #include <linux/printk.h>
21e9d376f0SJason Baron #include <linux/dynamic_debug.h>
221da177e4SLinus Torvalds #include <asm/byteorder.h>
231da177e4SLinus Torvalds #include <asm/bug.h>
241da177e4SLinus Torvalds 
254be929beSAlexey Dobriyan #define USHRT_MAX	((u16)(~0U))
264be929beSAlexey Dobriyan #define SHRT_MAX	((s16)(USHRT_MAX>>1))
274be929beSAlexey Dobriyan #define SHRT_MIN	((s16)(-SHRT_MAX - 1))
281da177e4SLinus Torvalds #define INT_MAX		((int)(~0U>>1))
291da177e4SLinus Torvalds #define INT_MIN		(-INT_MAX - 1)
301da177e4SLinus Torvalds #define UINT_MAX	(~0U)
311da177e4SLinus Torvalds #define LONG_MAX	((long)(~0UL>>1))
321da177e4SLinus Torvalds #define LONG_MIN	(-LONG_MAX - 1)
331da177e4SLinus Torvalds #define ULONG_MAX	(~0UL)
34111ebb6eSOGAWA Hirofumi #define LLONG_MAX	((long long)(~0ULL>>1))
35111ebb6eSOGAWA Hirofumi #define LLONG_MIN	(-LLONG_MAX - 1)
36111ebb6eSOGAWA Hirofumi #define ULLONG_MAX	(~0ULL)
371da177e4SLinus Torvalds 
381da177e4SLinus Torvalds #define STACK_MAGIC	0xdeadbeef
391da177e4SLinus Torvalds 
40a79ff731SAlexey Dobriyan #define ALIGN(x, a)		__ALIGN_KERNEL((x), (a))
419f93ff5bSAlexey Dobriyan #define __ALIGN_MASK(x, mask)	__ALIGN_KERNEL_MASK((x), (mask))
42a83308e6SMatthew Wilcox #define PTR_ALIGN(p, a)		((typeof(p))ALIGN((unsigned long)(p), (a)))
43f10db627SHerbert Xu #define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)
442ea58144SLinus Torvalds 
45c5e631cfSRusty Russell #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
46c5e631cfSRusty Russell 
479b3be9f9SYinghai Lu /*
489b3be9f9SYinghai Lu  * This looks more complex than it should be. But we need to
499b3be9f9SYinghai Lu  * get the type for the ~ right in round_down (it needs to be
509b3be9f9SYinghai Lu  * as wide as the result!), and we want to evaluate the macro
519b3be9f9SYinghai Lu  * arguments just once each.
529b3be9f9SYinghai Lu  */
539b3be9f9SYinghai Lu #define __round_mask(x, y) ((__typeof__(x))((y)-1))
549b3be9f9SYinghai Lu #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
559b3be9f9SYinghai Lu #define round_down(x, y) ((x) & ~__round_mask(x, y))
569b3be9f9SYinghai Lu 
574552d5dcSJan Beulich #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
58930631edSSteven Whitehouse #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
5936a26c69SNicholas Bellinger #define DIV_ROUND_UP_ULL(ll,d) \
6036a26c69SNicholas Bellinger 	({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
6136a26c69SNicholas Bellinger 
6236a26c69SNicholas Bellinger #if BITS_PER_LONG == 32
6336a26c69SNicholas Bellinger # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
6436a26c69SNicholas Bellinger #else
6536a26c69SNicholas Bellinger # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
6636a26c69SNicholas Bellinger #endif
67074e61ecSJames Morris 
68074e61ecSJames Morris /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
69b28efd54SEric Paris #define roundup(x, y) (					\
70b28efd54SEric Paris {							\
716070bf35STetsuo Handa 	const typeof(y) __y = y;			\
72b28efd54SEric Paris 	(((x) + (__y - 1)) / __y) * __y;		\
73b28efd54SEric Paris }							\
74b28efd54SEric Paris )
75686a0f3dSEric Paris #define rounddown(x, y) (				\
76686a0f3dSEric Paris {							\
77686a0f3dSEric Paris 	typeof(x) __x = (x);				\
78686a0f3dSEric Paris 	__x - (__x % (y));				\
79686a0f3dSEric Paris }							\
80686a0f3dSEric Paris )
819fe06081SDarrick J. Wong #define DIV_ROUND_CLOSEST(x, divisor)(			\
829fe06081SDarrick J. Wong {							\
839fe06081SDarrick J. Wong 	typeof(divisor) __divisor = divisor;		\
849fe06081SDarrick J. Wong 	(((x) + ((__divisor) / 2)) / (__divisor));	\
859fe06081SDarrick J. Wong }							\
869fe06081SDarrick J. Wong )
871da177e4SLinus Torvalds 
88ca31e146SEduard - Gabriel Munteanu #define _RET_IP_		(unsigned long)__builtin_return_address(0)
89ca31e146SEduard - Gabriel Munteanu #define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
90ca31e146SEduard - Gabriel Munteanu 
9190c699a9SBartlomiej Zolnierkiewicz #ifdef CONFIG_LBDAF
922da96acdSJens Axboe # include <asm/div64.h>
932da96acdSJens Axboe # define sector_div(a, b) do_div(a, b)
942da96acdSJens Axboe #else
952da96acdSJens Axboe # define sector_div(n, b)( \
962da96acdSJens Axboe { \
972da96acdSJens Axboe 	int _res; \
982da96acdSJens Axboe 	_res = (n) % (b); \
992da96acdSJens Axboe 	(n) /= (b); \
1002da96acdSJens Axboe 	_res; \
1012da96acdSJens Axboe } \
1022da96acdSJens Axboe )
1032da96acdSJens Axboe #endif
1042da96acdSJens Axboe 
105218e180eSAndrew Morton /**
106218e180eSAndrew Morton  * upper_32_bits - return bits 32-63 of a number
107218e180eSAndrew Morton  * @n: the number we're accessing
108218e180eSAndrew Morton  *
109218e180eSAndrew Morton  * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
110218e180eSAndrew Morton  * the "right shift count >= width of type" warning when that quantity is
111218e180eSAndrew Morton  * 32-bits.
112218e180eSAndrew Morton  */
113218e180eSAndrew Morton #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
114218e180eSAndrew Morton 
115204b885eSJoerg Roedel /**
116204b885eSJoerg Roedel  * lower_32_bits - return bits 0-31 of a number
117204b885eSJoerg Roedel  * @n: the number we're accessing
118204b885eSJoerg Roedel  */
119204b885eSJoerg Roedel #define lower_32_bits(n) ((u32)(n))
120204b885eSJoerg Roedel 
1211da177e4SLinus Torvalds struct completion;
122df2e71fbS[email protected] struct pt_regs;
123df2e71fbS[email protected] struct user;
1241da177e4SLinus Torvalds 
125070cb065SUwe Kleine-König #ifdef CONFIG_PREEMPT_VOLUNTARY
126070cb065SUwe Kleine-König extern int _cond_resched(void);
127070cb065SUwe Kleine-König # define might_resched() _cond_resched()
128070cb065SUwe Kleine-König #else
129070cb065SUwe Kleine-König # define might_resched() do { } while (0)
130070cb065SUwe Kleine-König #endif
131070cb065SUwe Kleine-König 
132d902db1eSFrederic Weisbecker #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
133d894837fSSimon Kagstrom   void __might_sleep(const char *file, int line, int preempt_offset);
1341da177e4SLinus Torvalds /**
1351da177e4SLinus Torvalds  * might_sleep - annotation for functions that can sleep
1361da177e4SLinus Torvalds  *
1371da177e4SLinus Torvalds  * this macro will print a stack trace if it is executed in an atomic
1381da177e4SLinus Torvalds  * context (spinlock, irq-handler, ...).
1391da177e4SLinus Torvalds  *
1401da177e4SLinus Torvalds  * This is a useful debugging help to be able to catch problems early and not
141e20ec991SJim Cromie  * be bitten later when the calling function happens to sleep when it is not
1421da177e4SLinus Torvalds  * supposed to.
1431da177e4SLinus Torvalds  */
144f8cbd99bSIngo Molnar # define might_sleep() \
145e4aafea2SFrederic Weisbecker 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
146f8cbd99bSIngo Molnar #else
147d894837fSSimon Kagstrom   static inline void __might_sleep(const char *file, int line,
148d894837fSSimon Kagstrom 				   int preempt_offset) { }
149f8cbd99bSIngo Molnar # define might_sleep() do { might_resched(); } while (0)
150f8cbd99bSIngo Molnar #endif
151f8cbd99bSIngo Molnar 
152368a5fa1SHua Zhong #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
153f8cbd99bSIngo Molnar 
15471a90484SAndrew Morton /*
15571a90484SAndrew Morton  * abs() handles unsigned and signed longs, ints, shorts and chars.  For all
15671a90484SAndrew Morton  * input types abs() returns a signed long.
15771a90484SAndrew Morton  * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
15871a90484SAndrew Morton  * for those.
15971a90484SAndrew Morton  */
1601da177e4SLinus Torvalds #define abs(x) ({						\
16171a90484SAndrew Morton 		long ret;					\
16271a90484SAndrew Morton 		if (sizeof(x) == sizeof(long)) {		\
163a49c59c0SRolf Eike Beer 			long __x = (x);				\
16471a90484SAndrew Morton 			ret = (__x < 0) ? -__x : __x;		\
16571a90484SAndrew Morton 		} else {					\
16671a90484SAndrew Morton 			int __x = (x);				\
16771a90484SAndrew Morton 			ret = (__x < 0) ? -__x : __x;		\
16871a90484SAndrew Morton 		}						\
16971a90484SAndrew Morton 		ret;						\
1701da177e4SLinus Torvalds 	})
1711da177e4SLinus Torvalds 
172658716d1SBrian Behlendorf #define abs64(x) ({				\
173658716d1SBrian Behlendorf 		s64 __x = (x);			\
174658716d1SBrian Behlendorf 		(__x < 0) ? -__x : __x;		\
175658716d1SBrian Behlendorf 	})
176658716d1SBrian Behlendorf 
1773ee1afa3SNick Piggin #ifdef CONFIG_PROVE_LOCKING
1783ee1afa3SNick Piggin void might_fault(void);
1793ee1afa3SNick Piggin #else
1803ee1afa3SNick Piggin static inline void might_fault(void)
1813ee1afa3SNick Piggin {
1823ee1afa3SNick Piggin 	might_sleep();
1833ee1afa3SNick Piggin }
1843ee1afa3SNick Piggin #endif
1853ee1afa3SNick Piggin 
186e041c683SAlan Stern extern struct atomic_notifier_head panic_notifier_list;
187c7ff0d9cSTAMUKI Shoichi extern long (*panic_blink)(int state);
1881da177e4SLinus Torvalds NORET_TYPE void panic(const char * fmt, ...)
189a586df06SAndi Kleen 	__attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
190dd287796SAndrew Morton extern void oops_enter(void);
191dd287796SAndrew Morton extern void oops_exit(void);
192863a6049SAnton Blanchard void print_oops_end_marker(void);
193dd287796SAndrew Morton extern int oops_may_print(void);
194ec701584SHarvey Harrison NORET_TYPE void do_exit(long error_code)
1951da177e4SLinus Torvalds 	ATTRIB_NORET;
1961da177e4SLinus Torvalds NORET_TYPE void complete_and_exit(struct completion *, long)
1971da177e4SLinus Torvalds 	ATTRIB_NORET;
19833ee3b2eSAlexey Dobriyan 
19933ee3b2eSAlexey Dobriyan /* Internal, do not use. */
20033ee3b2eSAlexey Dobriyan int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
20133ee3b2eSAlexey Dobriyan int __must_check _kstrtol(const char *s, unsigned int base, long *res);
20233ee3b2eSAlexey Dobriyan 
20333ee3b2eSAlexey Dobriyan int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
20433ee3b2eSAlexey Dobriyan int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
20533ee3b2eSAlexey Dobriyan static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
20633ee3b2eSAlexey Dobriyan {
20733ee3b2eSAlexey Dobriyan 	/*
20833ee3b2eSAlexey Dobriyan 	 * We want to shortcut function call, but
20933ee3b2eSAlexey Dobriyan 	 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
21033ee3b2eSAlexey Dobriyan 	 */
21133ee3b2eSAlexey Dobriyan 	if (sizeof(unsigned long) == sizeof(unsigned long long) &&
21233ee3b2eSAlexey Dobriyan 	    __alignof__(unsigned long) == __alignof__(unsigned long long))
21333ee3b2eSAlexey Dobriyan 		return kstrtoull(s, base, (unsigned long long *)res);
21433ee3b2eSAlexey Dobriyan 	else
21533ee3b2eSAlexey Dobriyan 		return _kstrtoul(s, base, res);
21633ee3b2eSAlexey Dobriyan }
21733ee3b2eSAlexey Dobriyan 
21833ee3b2eSAlexey Dobriyan static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
21933ee3b2eSAlexey Dobriyan {
22033ee3b2eSAlexey Dobriyan 	/*
22133ee3b2eSAlexey Dobriyan 	 * We want to shortcut function call, but
22233ee3b2eSAlexey Dobriyan 	 * __builtin_types_compatible_p(long, long long) = 0.
22333ee3b2eSAlexey Dobriyan 	 */
22433ee3b2eSAlexey Dobriyan 	if (sizeof(long) == sizeof(long long) &&
22533ee3b2eSAlexey Dobriyan 	    __alignof__(long) == __alignof__(long long))
22633ee3b2eSAlexey Dobriyan 		return kstrtoll(s, base, (long long *)res);
22733ee3b2eSAlexey Dobriyan 	else
22833ee3b2eSAlexey Dobriyan 		return _kstrtol(s, base, res);
22933ee3b2eSAlexey Dobriyan }
23033ee3b2eSAlexey Dobriyan 
23133ee3b2eSAlexey Dobriyan int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
23233ee3b2eSAlexey Dobriyan int __must_check kstrtoint(const char *s, unsigned int base, int *res);
23333ee3b2eSAlexey Dobriyan 
23433ee3b2eSAlexey Dobriyan static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
23533ee3b2eSAlexey Dobriyan {
23633ee3b2eSAlexey Dobriyan 	return kstrtoull(s, base, res);
23733ee3b2eSAlexey Dobriyan }
23833ee3b2eSAlexey Dobriyan 
23933ee3b2eSAlexey Dobriyan static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
24033ee3b2eSAlexey Dobriyan {
24133ee3b2eSAlexey Dobriyan 	return kstrtoll(s, base, res);
24233ee3b2eSAlexey Dobriyan }
24333ee3b2eSAlexey Dobriyan 
24433ee3b2eSAlexey Dobriyan static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
24533ee3b2eSAlexey Dobriyan {
24633ee3b2eSAlexey Dobriyan 	return kstrtouint(s, base, res);
24733ee3b2eSAlexey Dobriyan }
24833ee3b2eSAlexey Dobriyan 
24933ee3b2eSAlexey Dobriyan static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
25033ee3b2eSAlexey Dobriyan {
25133ee3b2eSAlexey Dobriyan 	return kstrtoint(s, base, res);
25233ee3b2eSAlexey Dobriyan }
25333ee3b2eSAlexey Dobriyan 
25433ee3b2eSAlexey Dobriyan int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
25533ee3b2eSAlexey Dobriyan int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
25633ee3b2eSAlexey Dobriyan int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
25733ee3b2eSAlexey Dobriyan int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
25833ee3b2eSAlexey Dobriyan 
259c196e32aSAlexey Dobriyan int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
260c196e32aSAlexey Dobriyan int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
261c196e32aSAlexey Dobriyan int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
262c196e32aSAlexey Dobriyan int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
263c196e32aSAlexey Dobriyan int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
264c196e32aSAlexey Dobriyan int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
265c196e32aSAlexey Dobriyan int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
266c196e32aSAlexey Dobriyan int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
267c196e32aSAlexey Dobriyan int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
268c196e32aSAlexey Dobriyan int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
269c196e32aSAlexey Dobriyan 
270c196e32aSAlexey Dobriyan static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
271c196e32aSAlexey Dobriyan {
272c196e32aSAlexey Dobriyan 	return kstrtoull_from_user(s, count, base, res);
273c196e32aSAlexey Dobriyan }
274c196e32aSAlexey Dobriyan 
275c196e32aSAlexey Dobriyan static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
276c196e32aSAlexey Dobriyan {
277c196e32aSAlexey Dobriyan 	return kstrtoll_from_user(s, count, base, res);
278c196e32aSAlexey Dobriyan }
279c196e32aSAlexey Dobriyan 
280c196e32aSAlexey Dobriyan static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
281c196e32aSAlexey Dobriyan {
282c196e32aSAlexey Dobriyan 	return kstrtouint_from_user(s, count, base, res);
283c196e32aSAlexey Dobriyan }
284c196e32aSAlexey Dobriyan 
285c196e32aSAlexey Dobriyan static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
286c196e32aSAlexey Dobriyan {
287c196e32aSAlexey Dobriyan 	return kstrtoint_from_user(s, count, base, res);
288c196e32aSAlexey Dobriyan }
289c196e32aSAlexey Dobriyan 
29067d0a075SJoe Perches /* Obsolete, do not use.  Use kstrto<foo> instead */
29167d0a075SJoe Perches 
2921da177e4SLinus Torvalds extern unsigned long simple_strtoul(const char *,char **,unsigned int);
2931da177e4SLinus Torvalds extern long simple_strtol(const char *,char **,unsigned int);
2941da177e4SLinus Torvalds extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
2951da177e4SLinus Torvalds extern long long simple_strtoll(const char *,char **,unsigned int);
29633ee3b2eSAlexey Dobriyan #define strict_strtoul	kstrtoul
29733ee3b2eSAlexey Dobriyan #define strict_strtol	kstrtol
29833ee3b2eSAlexey Dobriyan #define strict_strtoull	kstrtoull
29933ee3b2eSAlexey Dobriyan #define strict_strtoll	kstrtoll
30033ee3b2eSAlexey Dobriyan 
30167d0a075SJoe Perches /* lib/printf utilities */
30267d0a075SJoe Perches 
303b9075fa9SJoe Perches extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
304b9075fa9SJoe Perches extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
305b9075fa9SJoe Perches extern __printf(3, 4)
306b9075fa9SJoe Perches int snprintf(char *buf, size_t size, const char *fmt, ...);
307b9075fa9SJoe Perches extern __printf(3, 0)
308b9075fa9SJoe Perches int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
309b9075fa9SJoe Perches extern __printf(3, 4)
310b9075fa9SJoe Perches int scnprintf(char *buf, size_t size, const char *fmt, ...);
311b9075fa9SJoe Perches extern __printf(3, 0)
312b9075fa9SJoe Perches int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
313b9075fa9SJoe Perches extern __printf(2, 3)
314b9075fa9SJoe Perches char *kasprintf(gfp_t gfp, const char *fmt, ...);
31511443ec7SJeremy Fitzhardinge extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
3161da177e4SLinus Torvalds 
3171da177e4SLinus Torvalds extern int sscanf(const char *, const char *, ...)
3181da177e4SLinus Torvalds 	__attribute__ ((format (scanf, 2, 3)));
3191da177e4SLinus Torvalds extern int vsscanf(const char *, const char *, va_list)
3201da177e4SLinus Torvalds 	__attribute__ ((format (scanf, 2, 0)));
3211da177e4SLinus Torvalds 
3221da177e4SLinus Torvalds extern int get_option(char **str, int *pint);
3231da177e4SLinus Torvalds extern char *get_options(const char *str, int nints, int *ints);
324d974ae37SJeremy Fitzhardinge extern unsigned long long memparse(const char *ptr, char **retptr);
3251da177e4SLinus Torvalds 
3265e376613STrent Piepho extern int core_kernel_text(unsigned long addr);
327cdbe61bfSSteven Rostedt extern int core_kernel_data(unsigned long addr);
3281da177e4SLinus Torvalds extern int __kernel_text_address(unsigned long addr);
3291da177e4SLinus Torvalds extern int kernel_text_address(unsigned long addr);
330ab7476cfSArjan van de Ven extern int func_ptr_is_kernel_text(void *ptr);
331ab7476cfSArjan van de Ven 
33204a2e6a5SEric W. Biederman struct pid;
33304a2e6a5SEric W. Biederman extern struct pid *session_of_pgrp(struct pid *pgrp);
3341da177e4SLinus Torvalds 
3351da177e4SLinus Torvalds unsigned long int_sqrt(unsigned long);
3361da177e4SLinus Torvalds 
3371da177e4SLinus Torvalds extern void bust_spinlocks(int yes);
338e3e8a75dSKirill Korotaev extern void wake_up_klogd(void);
3391da177e4SLinus Torvalds extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
340aa727107SAdrian Bunk extern int panic_timeout;
3411da177e4SLinus Torvalds extern int panic_on_oops;
3428da5addaSDon Zickus extern int panic_on_unrecovered_nmi;
3435211a242SKurt Garloff extern int panic_on_io_nmi;
3441da177e4SLinus Torvalds extern const char *print_tainted(void);
34525ddbb18SAndi Kleen extern void add_taint(unsigned flag);
34625ddbb18SAndi Kleen extern int test_taint(unsigned flag);
34725ddbb18SAndi Kleen extern unsigned long get_taint(void);
348b920de1bSDavid Howells extern int root_mountflags;
3491da177e4SLinus Torvalds 
3502ce802f6STejun Heo extern bool early_boot_irqs_disabled;
3512ce802f6STejun Heo 
3521da177e4SLinus Torvalds /* Values used for system_state */
3531da177e4SLinus Torvalds extern enum system_states {
3541da177e4SLinus Torvalds 	SYSTEM_BOOTING,
3551da177e4SLinus Torvalds 	SYSTEM_RUNNING,
3561da177e4SLinus Torvalds 	SYSTEM_HALT,
3571da177e4SLinus Torvalds 	SYSTEM_POWER_OFF,
3581da177e4SLinus Torvalds 	SYSTEM_RESTART,
359729b4d4cSAlexey Starikovskiy 	SYSTEM_SUSPEND_DISK,
3601da177e4SLinus Torvalds } system_state;
3611da177e4SLinus Torvalds 
36225ddbb18SAndi Kleen #define TAINT_PROPRIETARY_MODULE	0
36325ddbb18SAndi Kleen #define TAINT_FORCED_MODULE		1
36425ddbb18SAndi Kleen #define TAINT_UNSAFE_SMP		2
36525ddbb18SAndi Kleen #define TAINT_FORCED_RMMOD		3
36625ddbb18SAndi Kleen #define TAINT_MACHINE_CHECK		4
36725ddbb18SAndi Kleen #define TAINT_BAD_PAGE			5
36825ddbb18SAndi Kleen #define TAINT_USER			6
36925ddbb18SAndi Kleen #define TAINT_DIE			7
37025ddbb18SAndi Kleen #define TAINT_OVERRIDDEN_ACPI_TABLE	8
37125ddbb18SAndi Kleen #define TAINT_WARN			9
37226e9a397SLinus Torvalds #define TAINT_CRAP			10
37392946bc7SBen Hutchings #define TAINT_FIRMWARE_WORKAROUND	11
3742449b8baSBen Hutchings #define TAINT_OOT_MODULE		12
3751da177e4SLinus Torvalds 
3763fc95772SHarvey Harrison extern const char hex_asc[];
3773fc95772SHarvey Harrison #define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
3783fc95772SHarvey Harrison #define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
3793fc95772SHarvey Harrison 
38055036ba7SAndy Shevchenko static inline char *hex_byte_pack(char *buf, u8 byte)
3813fc95772SHarvey Harrison {
3823fc95772SHarvey Harrison 	*buf++ = hex_asc_hi(byte);
3833fc95772SHarvey Harrison 	*buf++ = hex_asc_lo(byte);
3843fc95772SHarvey Harrison 	return buf;
3853fc95772SHarvey Harrison }
38699eaf3c4SRandy Dunlap 
38755036ba7SAndy Shevchenko static inline char * __deprecated pack_hex_byte(char *buf, u8 byte)
38855036ba7SAndy Shevchenko {
38955036ba7SAndy Shevchenko 	return hex_byte_pack(buf, byte);
39055036ba7SAndy Shevchenko }
39155036ba7SAndy Shevchenko 
39290378889SAndy Shevchenko extern int hex_to_bin(char ch);
393b7804983SMimi Zohar extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
39490378889SAndy Shevchenko 
3958a64f336SJoe Perches /*
396526211bcSIngo Molnar  * General tracing related utility functions - trace_printk(),
3972002c258SSteven Rostedt  * tracing_on/tracing_off and tracing_start()/tracing_stop
3982002c258SSteven Rostedt  *
3992002c258SSteven Rostedt  * Use tracing_on/tracing_off when you want to quickly turn on or off
4002002c258SSteven Rostedt  * tracing. It simply enables or disables the recording of the trace events.
401156f5a78SGeunSik Lim  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
4022002c258SSteven Rostedt  * file, which gives a means for the kernel and userspace to interact.
4032002c258SSteven Rostedt  * Place a tracing_off() in the kernel where you want tracing to end.
4042002c258SSteven Rostedt  * From user space, examine the trace, and then echo 1 > tracing_on
4052002c258SSteven Rostedt  * to continue tracing.
4062002c258SSteven Rostedt  *
4072002c258SSteven Rostedt  * tracing_stop/tracing_start has slightly more overhead. It is used
4082002c258SSteven Rostedt  * by things like suspend to ram where disabling the recording of the
4092002c258SSteven Rostedt  * trace is not enough, but tracing must actually stop because things
4102002c258SSteven Rostedt  * like calling smp_processor_id() may crash the system.
4112002c258SSteven Rostedt  *
4122002c258SSteven Rostedt  * Most likely, you want to use tracing_on/tracing_off.
413526211bcSIngo Molnar  */
4142002c258SSteven Rostedt #ifdef CONFIG_RING_BUFFER
4152002c258SSteven Rostedt void tracing_on(void);
4162002c258SSteven Rostedt void tracing_off(void);
4172002c258SSteven Rostedt /* trace_off_permanent stops recording with no way to bring it back */
4182002c258SSteven Rostedt void tracing_off_permanent(void);
4192002c258SSteven Rostedt int tracing_is_on(void);
4202002c258SSteven Rostedt #else
4212002c258SSteven Rostedt static inline void tracing_on(void) { }
4222002c258SSteven Rostedt static inline void tracing_off(void) { }
4232002c258SSteven Rostedt static inline void tracing_off_permanent(void) { }
4242002c258SSteven Rostedt static inline int tracing_is_on(void) { return 0; }
4252002c258SSteven Rostedt #endif
426cecbca96SFrederic Weisbecker 
427cecbca96SFrederic Weisbecker enum ftrace_dump_mode {
428cecbca96SFrederic Weisbecker 	DUMP_NONE,
429cecbca96SFrederic Weisbecker 	DUMP_ALL,
430cecbca96SFrederic Weisbecker 	DUMP_ORIG,
431cecbca96SFrederic Weisbecker };
432cecbca96SFrederic Weisbecker 
433526211bcSIngo Molnar #ifdef CONFIG_TRACING
434526211bcSIngo Molnar extern void tracing_start(void);
435526211bcSIngo Molnar extern void tracing_stop(void);
436526211bcSIngo Molnar extern void ftrace_off_permanent(void);
437526211bcSIngo Molnar 
438b9075fa9SJoe Perches static inline __printf(1, 2)
439b9075fa9SJoe Perches void ____trace_printk_check_format(const char *fmt, ...)
440769b0441SFrederic Weisbecker {
441769b0441SFrederic Weisbecker }
442769b0441SFrederic Weisbecker #define __trace_printk_check_format(fmt, args...)			\
443769b0441SFrederic Weisbecker do {									\
444769b0441SFrederic Weisbecker 	if (0)								\
445769b0441SFrederic Weisbecker 		____trace_printk_check_format(fmt, ##args);		\
446769b0441SFrederic Weisbecker } while (0)
447769b0441SFrederic Weisbecker 
448526211bcSIngo Molnar /**
449526211bcSIngo Molnar  * trace_printk - printf formatting in the ftrace buffer
450526211bcSIngo Molnar  * @fmt: the printf format for printing
451526211bcSIngo Molnar  *
452526211bcSIngo Molnar  * Note: __trace_printk is an internal function for trace_printk and
453526211bcSIngo Molnar  *       the @ip is passed in via the trace_printk macro.
454526211bcSIngo Molnar  *
455526211bcSIngo Molnar  * This function allows a kernel developer to debug fast path sections
456526211bcSIngo Molnar  * that printk is not appropriate for. By scattering in various
457526211bcSIngo Molnar  * printk like tracing in the code, a developer can quickly see
458526211bcSIngo Molnar  * where problems are occurring.
459526211bcSIngo Molnar  *
460526211bcSIngo Molnar  * This is intended as a debugging tool for the developer only.
461526211bcSIngo Molnar  * Please refrain from leaving trace_printks scattered around in
462526211bcSIngo Molnar  * your code.
463526211bcSIngo Molnar  */
464769b0441SFrederic Weisbecker 
465769b0441SFrederic Weisbecker #define trace_printk(fmt, args...)					\
466769b0441SFrederic Weisbecker do {									\
467769b0441SFrederic Weisbecker 	__trace_printk_check_format(fmt, ##args);			\
46848ead020SFrederic Weisbecker 	if (__builtin_constant_p(fmt)) {				\
46948ead020SFrederic Weisbecker 		static const char *trace_printk_fmt			\
47048ead020SFrederic Weisbecker 		  __attribute__((section("__trace_printk_fmt"))) =	\
47148ead020SFrederic Weisbecker 			__builtin_constant_p(fmt) ? fmt : NULL;		\
47248ead020SFrederic Weisbecker 									\
47348ead020SFrederic Weisbecker 		__trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);	\
47448ead020SFrederic Weisbecker 	} else								\
47548ead020SFrederic Weisbecker 		__trace_printk(_THIS_IP_, fmt, ##args);		\
476769b0441SFrederic Weisbecker } while (0)
477769b0441SFrederic Weisbecker 
478b9075fa9SJoe Perches extern __printf(2, 3)
479b9075fa9SJoe Perches int __trace_bprintk(unsigned long ip, const char *fmt, ...);
48048ead020SFrederic Weisbecker 
481b9075fa9SJoe Perches extern __printf(2, 3)
482b9075fa9SJoe Perches int __trace_printk(unsigned long ip, const char *fmt, ...);
483769b0441SFrederic Weisbecker 
48403889384SSteven Rostedt extern void trace_dump_stack(void);
48503889384SSteven Rostedt 
48648ead020SFrederic Weisbecker /*
48748ead020SFrederic Weisbecker  * The double __builtin_constant_p is because gcc will give us an error
48848ead020SFrederic Weisbecker  * if we try to allocate the static variable to fmt if it is not a
48948ead020SFrederic Weisbecker  * constant. Even with the outer if statement.
49048ead020SFrederic Weisbecker  */
491769b0441SFrederic Weisbecker #define ftrace_vprintk(fmt, vargs)					\
492769b0441SFrederic Weisbecker do {									\
49348ead020SFrederic Weisbecker 	if (__builtin_constant_p(fmt)) {				\
494769b0441SFrederic Weisbecker 		static const char *trace_printk_fmt			\
49548ead020SFrederic Weisbecker 		  __attribute__((section("__trace_printk_fmt"))) =	\
49648ead020SFrederic Weisbecker 			__builtin_constant_p(fmt) ? fmt : NULL;		\
4977bffc23eSIngo Molnar 									\
49848ead020SFrederic Weisbecker 		__ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);	\
49948ead020SFrederic Weisbecker 	} else								\
50048ead020SFrederic Weisbecker 		__ftrace_vprintk(_THIS_IP_, fmt, vargs);		\
501769b0441SFrederic Weisbecker } while (0)
502769b0441SFrederic Weisbecker 
503526211bcSIngo Molnar extern int
50448ead020SFrederic Weisbecker __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
50548ead020SFrederic Weisbecker 
50648ead020SFrederic Weisbecker extern int
507526211bcSIngo Molnar __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
508769b0441SFrederic Weisbecker 
509cecbca96SFrederic Weisbecker extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
510526211bcSIngo Molnar #else
511b9075fa9SJoe Perches static inline __printf(1, 2)
512b9075fa9SJoe Perches int trace_printk(const char *fmt, ...);
513526211bcSIngo Molnar 
514526211bcSIngo Molnar static inline void tracing_start(void) { }
515526211bcSIngo Molnar static inline void tracing_stop(void) { }
516526211bcSIngo Molnar static inline void ftrace_off_permanent(void) { }
517e36c5458SSteven Rostedt static inline void trace_dump_stack(void) { }
518526211bcSIngo Molnar static inline int
519526211bcSIngo Molnar trace_printk(const char *fmt, ...)
520526211bcSIngo Molnar {
521526211bcSIngo Molnar 	return 0;
522526211bcSIngo Molnar }
523526211bcSIngo Molnar static inline int
524526211bcSIngo Molnar ftrace_vprintk(const char *fmt, va_list ap)
525526211bcSIngo Molnar {
526526211bcSIngo Molnar 	return 0;
527526211bcSIngo Molnar }
528cecbca96SFrederic Weisbecker static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
529769b0441SFrederic Weisbecker #endif /* CONFIG_TRACING */
530526211bcSIngo Molnar 
531526211bcSIngo Molnar /*
532bdf4bbaaSHarvey Harrison  * min()/max()/clamp() macros that also do
5331da177e4SLinus Torvalds  * strict type-checking.. See the
5341da177e4SLinus Torvalds  * "unnecessary" pointer comparison.
5351da177e4SLinus Torvalds  */
5361da177e4SLinus Torvalds #define min(x, y) ({				\
537bdf4bbaaSHarvey Harrison 	typeof(x) _min1 = (x);			\
538bdf4bbaaSHarvey Harrison 	typeof(y) _min2 = (y);			\
539bdf4bbaaSHarvey Harrison 	(void) (&_min1 == &_min2);		\
540bdf4bbaaSHarvey Harrison 	_min1 < _min2 ? _min1 : _min2; })
5411da177e4SLinus Torvalds 
5421da177e4SLinus Torvalds #define max(x, y) ({				\
543bdf4bbaaSHarvey Harrison 	typeof(x) _max1 = (x);			\
544bdf4bbaaSHarvey Harrison 	typeof(y) _max2 = (y);			\
545bdf4bbaaSHarvey Harrison 	(void) (&_max1 == &_max2);		\
546bdf4bbaaSHarvey Harrison 	_max1 > _max2 ? _max1 : _max2; })
547bdf4bbaaSHarvey Harrison 
548f27c85c5SHagen Paul Pfeifer #define min3(x, y, z) ({			\
549f27c85c5SHagen Paul Pfeifer 	typeof(x) _min1 = (x);			\
550f27c85c5SHagen Paul Pfeifer 	typeof(y) _min2 = (y);			\
551f27c85c5SHagen Paul Pfeifer 	typeof(z) _min3 = (z);			\
552f27c85c5SHagen Paul Pfeifer 	(void) (&_min1 == &_min2);		\
553f27c85c5SHagen Paul Pfeifer 	(void) (&_min1 == &_min3);		\
554f27c85c5SHagen Paul Pfeifer 	_min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
555f27c85c5SHagen Paul Pfeifer 		(_min2 < _min3 ? _min2 : _min3); })
556f27c85c5SHagen Paul Pfeifer 
557f27c85c5SHagen Paul Pfeifer #define max3(x, y, z) ({			\
558f27c85c5SHagen Paul Pfeifer 	typeof(x) _max1 = (x);			\
559f27c85c5SHagen Paul Pfeifer 	typeof(y) _max2 = (y);			\
560f27c85c5SHagen Paul Pfeifer 	typeof(z) _max3 = (z);			\
561f27c85c5SHagen Paul Pfeifer 	(void) (&_max1 == &_max2);		\
562f27c85c5SHagen Paul Pfeifer 	(void) (&_max1 == &_max3);		\
563f27c85c5SHagen Paul Pfeifer 	_max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
564f27c85c5SHagen Paul Pfeifer 		(_max2 > _max3 ? _max2 : _max3); })
565f27c85c5SHagen Paul Pfeifer 
566bdf4bbaaSHarvey Harrison /**
567c8bf1336SMartin K. Petersen  * min_not_zero - return the minimum that is _not_ zero, unless both are zero
568c8bf1336SMartin K. Petersen  * @x: value1
569c8bf1336SMartin K. Petersen  * @y: value2
570c8bf1336SMartin K. Petersen  */
571c8bf1336SMartin K. Petersen #define min_not_zero(x, y) ({			\
572c8bf1336SMartin K. Petersen 	typeof(x) __x = (x);			\
573c8bf1336SMartin K. Petersen 	typeof(y) __y = (y);			\
574c8bf1336SMartin K. Petersen 	__x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
575c8bf1336SMartin K. Petersen 
576c8bf1336SMartin K. Petersen /**
577bdf4bbaaSHarvey Harrison  * clamp - return a value clamped to a given range with strict typechecking
578bdf4bbaaSHarvey Harrison  * @val: current value
579bdf4bbaaSHarvey Harrison  * @min: minimum allowable value
580bdf4bbaaSHarvey Harrison  * @max: maximum allowable value
581bdf4bbaaSHarvey Harrison  *
582bdf4bbaaSHarvey Harrison  * This macro does strict typechecking of min/max to make sure they are of the
583bdf4bbaaSHarvey Harrison  * same type as val.  See the unnecessary pointer comparisons.
584bdf4bbaaSHarvey Harrison  */
585bdf4bbaaSHarvey Harrison #define clamp(val, min, max) ({			\
586bdf4bbaaSHarvey Harrison 	typeof(val) __val = (val);		\
587bdf4bbaaSHarvey Harrison 	typeof(min) __min = (min);		\
588bdf4bbaaSHarvey Harrison 	typeof(max) __max = (max);		\
589bdf4bbaaSHarvey Harrison 	(void) (&__val == &__min);		\
590bdf4bbaaSHarvey Harrison 	(void) (&__val == &__max);		\
591bdf4bbaaSHarvey Harrison 	__val = __val < __min ? __min: __val;	\
592bdf4bbaaSHarvey Harrison 	__val > __max ? __max: __val; })
5931da177e4SLinus Torvalds 
5941da177e4SLinus Torvalds /*
5951da177e4SLinus Torvalds  * ..and if you can't take the strict
5961da177e4SLinus Torvalds  * types, you can specify one yourself.
5971da177e4SLinus Torvalds  *
598bdf4bbaaSHarvey Harrison  * Or not use min/max/clamp at all, of course.
5991da177e4SLinus Torvalds  */
600bdf4bbaaSHarvey Harrison #define min_t(type, x, y) ({			\
601bdf4bbaaSHarvey Harrison 	type __min1 = (x);			\
602bdf4bbaaSHarvey Harrison 	type __min2 = (y);			\
603bdf4bbaaSHarvey Harrison 	__min1 < __min2 ? __min1: __min2; })
6041da177e4SLinus Torvalds 
605bdf4bbaaSHarvey Harrison #define max_t(type, x, y) ({			\
606bdf4bbaaSHarvey Harrison 	type __max1 = (x);			\
607bdf4bbaaSHarvey Harrison 	type __max2 = (y);			\
608bdf4bbaaSHarvey Harrison 	__max1 > __max2 ? __max1: __max2; })
609bdf4bbaaSHarvey Harrison 
610bdf4bbaaSHarvey Harrison /**
611bdf4bbaaSHarvey Harrison  * clamp_t - return a value clamped to a given range using a given type
612bdf4bbaaSHarvey Harrison  * @type: the type of variable to use
613bdf4bbaaSHarvey Harrison  * @val: current value
614bdf4bbaaSHarvey Harrison  * @min: minimum allowable value
615bdf4bbaaSHarvey Harrison  * @max: maximum allowable value
616bdf4bbaaSHarvey Harrison  *
617bdf4bbaaSHarvey Harrison  * This macro does no typechecking and uses temporary variables of type
618bdf4bbaaSHarvey Harrison  * 'type' to make all the comparisons.
619bdf4bbaaSHarvey Harrison  */
620bdf4bbaaSHarvey Harrison #define clamp_t(type, val, min, max) ({		\
621bdf4bbaaSHarvey Harrison 	type __val = (val);			\
622bdf4bbaaSHarvey Harrison 	type __min = (min);			\
623bdf4bbaaSHarvey Harrison 	type __max = (max);			\
624bdf4bbaaSHarvey Harrison 	__val = __val < __min ? __min: __val;	\
625bdf4bbaaSHarvey Harrison 	__val > __max ? __max: __val; })
626bdf4bbaaSHarvey Harrison 
627bdf4bbaaSHarvey Harrison /**
628bdf4bbaaSHarvey Harrison  * clamp_val - return a value clamped to a given range using val's type
629bdf4bbaaSHarvey Harrison  * @val: current value
630bdf4bbaaSHarvey Harrison  * @min: minimum allowable value
631bdf4bbaaSHarvey Harrison  * @max: maximum allowable value
632bdf4bbaaSHarvey Harrison  *
633bdf4bbaaSHarvey Harrison  * This macro does no typechecking and uses temporary variables of whatever
634bdf4bbaaSHarvey Harrison  * type the input argument 'val' is.  This is useful when val is an unsigned
635bdf4bbaaSHarvey Harrison  * type and min and max are literals that will otherwise be assigned a signed
636bdf4bbaaSHarvey Harrison  * integer type.
637bdf4bbaaSHarvey Harrison  */
638bdf4bbaaSHarvey Harrison #define clamp_val(val, min, max) ({		\
639bdf4bbaaSHarvey Harrison 	typeof(val) __val = (val);		\
640bdf4bbaaSHarvey Harrison 	typeof(val) __min = (min);		\
641bdf4bbaaSHarvey Harrison 	typeof(val) __max = (max);		\
642bdf4bbaaSHarvey Harrison 	__val = __val < __min ? __min: __val;	\
643bdf4bbaaSHarvey Harrison 	__val > __max ? __max: __val; })
6441da177e4SLinus Torvalds 
64591f68b73SWu Fengguang 
64691f68b73SWu Fengguang /*
64791f68b73SWu Fengguang  * swap - swap value of @a and @b
64891f68b73SWu Fengguang  */
649ac7b9004SPeter Zijlstra #define swap(a, b) \
650ac7b9004SPeter Zijlstra 	do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
65191f68b73SWu Fengguang 
6521da177e4SLinus Torvalds /**
6531da177e4SLinus Torvalds  * container_of - cast a member of a structure out to the containing structure
6541da177e4SLinus Torvalds  * @ptr:	the pointer to the member.
6551da177e4SLinus Torvalds  * @type:	the type of the container struct this is embedded in.
6561da177e4SLinus Torvalds  * @member:	the name of the member within the struct.
6571da177e4SLinus Torvalds  *
6581da177e4SLinus Torvalds  */
6591da177e4SLinus Torvalds #define container_of(ptr, type, member) ({			\
6601da177e4SLinus Torvalds 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
6611da177e4SLinus Torvalds 	(type *)( (char *)__mptr - offsetof(type,member) );})
6621da177e4SLinus Torvalds 
663903c0c7cSKOSAKI Motohiro #ifdef __CHECKER__
664903c0c7cSKOSAKI Motohiro #define BUILD_BUG_ON_NOT_POWER_OF_2(n)
665ca39599cSDr. David Alan Gilbert #define BUILD_BUG_ON_ZERO(e) (0)
666ca39599cSDr. David Alan Gilbert #define BUILD_BUG_ON_NULL(e) ((void*)0)
667903c0c7cSKOSAKI Motohiro #define BUILD_BUG_ON(condition)
668*1399ff86SDavid Daney #define BUILD_BUG() (0)
669903c0c7cSKOSAKI Motohiro #else /* __CHECKER__ */
670903c0c7cSKOSAKI Motohiro 
671cc8ef6ebSRoland Dreier /* Force a compilation error if a constant expression is not a power of 2 */
672cc8ef6ebSRoland Dreier #define BUILD_BUG_ON_NOT_POWER_OF_2(n)			\
673cc8ef6ebSRoland Dreier 	BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
674cc8ef6ebSRoland Dreier 
6754552d5dcSJan Beulich /* Force a compilation error if condition is true, but also produce a
6764552d5dcSJan Beulich    result (of value 0 and type size_t), so the expression can be used
6774552d5dcSJan Beulich    e.g. in a structure initializer (or where-ever else comma expressions
6784552d5dcSJan Beulich    aren't permitted). */
6798c87df45SJan Beulich #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
6808c87df45SJan Beulich #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
6814552d5dcSJan Beulich 
6827ef88ad5SRusty Russell /**
6837ef88ad5SRusty Russell  * BUILD_BUG_ON - break compile if a condition is true.
684ffbbf2daSRandy Dunlap  * @condition: the condition which the compiler should know is false.
6857ef88ad5SRusty Russell  *
6867ef88ad5SRusty Russell  * If you have some code which relies on certain constants being equal, or
6877ef88ad5SRusty Russell  * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
6887ef88ad5SRusty Russell  * detect if someone changes it.
6897ef88ad5SRusty Russell  *
6907ef88ad5SRusty Russell  * The implementation uses gcc's reluctance to create a negative array, but
6917ef88ad5SRusty Russell  * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
6927ef88ad5SRusty Russell  * to inline functions).  So as a fallback we use the optimizer; if it can't
6937ef88ad5SRusty Russell  * prove the condition is false, it will cause a link error on the undefined
6947ef88ad5SRusty Russell  * "__build_bug_on_failed".  This error message can be harder to track down
6957ef88ad5SRusty Russell  * though, hence the two different methods.
6967ef88ad5SRusty Russell  */
6977ef88ad5SRusty Russell #ifndef __OPTIMIZE__
6987ef88ad5SRusty Russell #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
6997ef88ad5SRusty Russell #else
7007ef88ad5SRusty Russell extern int __build_bug_on_failed;
7017ef88ad5SRusty Russell #define BUILD_BUG_ON(condition)					\
7027ef88ad5SRusty Russell 	do {							\
7037ef88ad5SRusty Russell 		((void)sizeof(char[1 - 2*!!(condition)]));	\
7047ef88ad5SRusty Russell 		if (condition) __build_bug_on_failed = 1;	\
7057ef88ad5SRusty Russell 	} while(0)
7067ef88ad5SRusty Russell #endif
707*1399ff86SDavid Daney 
708*1399ff86SDavid Daney /**
709*1399ff86SDavid Daney  * BUILD_BUG - break compile if used.
710*1399ff86SDavid Daney  *
711*1399ff86SDavid Daney  * If you have some code that you expect the compiler to eliminate at
712*1399ff86SDavid Daney  * build time, you should use BUILD_BUG to detect if it is
713*1399ff86SDavid Daney  * unexpectedly used.
714*1399ff86SDavid Daney  */
715*1399ff86SDavid Daney #define BUILD_BUG()						\
716*1399ff86SDavid Daney 	do {							\
717*1399ff86SDavid Daney 		extern void __build_bug_failed(void)		\
718*1399ff86SDavid Daney 			__linktime_error("BUILD_BUG failed");	\
719*1399ff86SDavid Daney 		__build_bug_failed();				\
720*1399ff86SDavid Daney 	} while (0)
721*1399ff86SDavid Daney 
722903c0c7cSKOSAKI Motohiro #endif	/* __CHECKER__ */
7237ef88ad5SRusty Russell 
724b9d4f426SArnaud Lacombe /* Trap pasters of __FUNCTION__ at compile-time */
725b9d4f426SArnaud Lacombe #define __FUNCTION__ (__func__)
726b9d4f426SArnaud Lacombe 
727b9d4f426SArnaud Lacombe /* This helps us to avoid #ifdef CONFIG_NUMA */
728b9d4f426SArnaud Lacombe #ifdef CONFIG_NUMA
729b9d4f426SArnaud Lacombe #define NUMA_BUILD 1
730b9d4f426SArnaud Lacombe #else
731b9d4f426SArnaud Lacombe #define NUMA_BUILD 0
732b9d4f426SArnaud Lacombe #endif
733b9d4f426SArnaud Lacombe 
734b9d4f426SArnaud Lacombe /* This helps us avoid #ifdef CONFIG_COMPACTION */
735b9d4f426SArnaud Lacombe #ifdef CONFIG_COMPACTION
736b9d4f426SArnaud Lacombe #define COMPACTION_BUILD 1
737b9d4f426SArnaud Lacombe #else
738b9d4f426SArnaud Lacombe #define COMPACTION_BUILD 0
739b9d4f426SArnaud Lacombe #endif
740b9d4f426SArnaud Lacombe 
741b9d4f426SArnaud Lacombe /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
742b9d4f426SArnaud Lacombe #ifdef CONFIG_FTRACE_MCOUNT_RECORD
743b9d4f426SArnaud Lacombe # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
744b9d4f426SArnaud Lacombe #endif
7459d00f92fSWANG Cong 
7469d00f92fSWANG Cong struct sysinfo;
7479d00f92fSWANG Cong extern int do_sysinfo(struct sysinfo *info);
7489d00f92fSWANG Cong 
7499d00f92fSWANG Cong #endif /* __KERNEL__ */
7509d00f92fSWANG Cong 
7519d00f92fSWANG Cong #define SI_LOAD_SHIFT	16
7529d00f92fSWANG Cong struct sysinfo {
7539d00f92fSWANG Cong 	long uptime;			/* Seconds since boot */
7549d00f92fSWANG Cong 	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
7559d00f92fSWANG Cong 	unsigned long totalram;		/* Total usable main memory size */
7569d00f92fSWANG Cong 	unsigned long freeram;		/* Available memory size */
7579d00f92fSWANG Cong 	unsigned long sharedram;	/* Amount of shared memory */
7589d00f92fSWANG Cong 	unsigned long bufferram;	/* Memory used by buffers */
7599d00f92fSWANG Cong 	unsigned long totalswap;	/* Total swap space size */
7609d00f92fSWANG Cong 	unsigned long freeswap;		/* swap space still available */
7619d00f92fSWANG Cong 	unsigned short procs;		/* Number of current processes */
7629d00f92fSWANG Cong 	unsigned short pad;		/* explicit padding for m68k */
7639d00f92fSWANG Cong 	unsigned long totalhigh;	/* Total high memory size */
7649d00f92fSWANG Cong 	unsigned long freehigh;		/* Available high memory size */
7659d00f92fSWANG Cong 	unsigned int mem_unit;		/* Memory unit size in bytes */
7669d00f92fSWANG Cong 	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
7679d00f92fSWANG Cong };
7689d00f92fSWANG Cong 
7691da177e4SLinus Torvalds #endif
770