[deliverable/linux.git] / include / linux / kernel.h

#ifndef _LINUX_KERNEL_H
#define _LINUX_KERNEL_H

/*
 * 'kernel.h' contains some often-used function prototypes etc
 */

#ifdef __KERNEL__

#include <stdarg.h>
#include <linux/linkage.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <linux/compiler.h>
#include <linux/bitops.h>
#include <asm/byteorder.h>
#include <asm/bug.h>

extern const char linux_banner[];

#define INT_MAX		((int)(~0U>>1))
#define INT_MIN		(-INT_MAX - 1)
#define UINT_MAX	(~0U)
#define LONG_MAX	((long)(~0UL>>1))
#define LONG_MIN	(-LONG_MAX - 1)
#define ULONG_MAX	(~0UL)
#define LLONG_MAX	((long long)(~0ULL>>1))
#define LLONG_MIN	(-LLONG_MAX - 1)
#define ULLONG_MAX	(~0ULL)

#define STACK_MAGIC	0xdeadbeef

#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
#define ALIGN(x,a) (((x)+(a)-1)&~((a)-1))
#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))

#define	KERN_EMERG	"<0>"	/* system is unusable			*/
#define	KERN_ALERT	"<1>"	/* action must be taken immediately	*/
#define	KERN_CRIT	"<2>"	/* critical conditions			*/
#define	KERN_ERR	"<3>"	/* error conditions			*/
#define	KERN_WARNING	"<4>"	/* warning conditions			*/
#define	KERN_NOTICE	"<5>"	/* normal but significant condition	*/
#define	KERN_INFO	"<6>"	/* informational			*/
#define	KERN_DEBUG	"<7>"	/* debug-level messages			*/

extern int console_printk[];

#define console_loglevel (console_printk[0])
#define default_message_loglevel (console_printk[1])
#define minimum_console_loglevel (console_printk[2])
#define default_console_loglevel (console_printk[3])

struct completion;
struct pt_regs;
struct user;

/**
 * might_sleep - annotation for functions that can sleep
 *
 * this macro will print a stack trace if it is executed in an atomic
 * context (spinlock, irq-handler, ...).
 *
 * This is a useful debugging help to be able to catch problems early and not
 * be biten later when the calling function happens to sleep when it is not
 * supposed to.
 */
#ifdef CONFIG_PREEMPT_VOLUNTARY
extern int cond_resched(void);
# define might_resched() cond_resched()
#else
# define might_resched() do { } while (0)
#endif

#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  void __might_sleep(char *file, int line);
# define might_sleep() \
	do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
#else
# define might_sleep() do { might_resched(); } while (0)
#endif

#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)

#define abs(x) ({				\
		int __x = (x);			\
		(__x < 0) ? -__x : __x;		\
	})

#define labs(x) ({				\
		long __x = (x);			\
		(__x < 0) ? -__x : __x;		\
	})

extern struct atomic_notifier_head panic_notifier_list;
extern long (*panic_blink)(long time);
NORET_TYPE void panic(const char * fmt, ...)
	__attribute__ ((NORET_AND format (printf, 1, 2)));
extern void oops_enter(void);
extern void oops_exit(void);
extern int oops_may_print(void);
fastcall NORET_TYPE void do_exit(long error_code)
	ATTRIB_NORET;
NORET_TYPE void complete_and_exit(struct completion *, long)
	ATTRIB_NORET;
extern unsigned long simple_strtoul(const char *,char **,unsigned int);
extern long simple_strtol(const char *,char **,unsigned int);
extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
extern long long simple_strtoll(const char *,char **,unsigned int);
extern int sprintf(char * buf, const char * fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int vsprintf(char *buf, const char *, va_list)
	__attribute__ ((format (printf, 2, 0)));
extern int snprintf(char * buf, size_t size, const char * fmt, ...)
	__attribute__ ((format (printf, 3, 4)));
extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
	__attribute__ ((format (printf, 3, 0)));
extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
	__attribute__ ((format (printf, 3, 4)));
extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
	__attribute__ ((format (printf, 3, 0)));
extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));

extern int sscanf(const char *, const char *, ...)
	__attribute__ ((format (scanf, 2, 3)));
extern int vsscanf(const char *, const char *, va_list)
	__attribute__ ((format (scanf, 2, 0)));

extern int get_option(char **str, int *pint);
extern char *get_options(const char *str, int nints, int *ints);
extern unsigned long long memparse(char *ptr, char **retptr);

extern int core_kernel_text(unsigned long addr);
extern int __kernel_text_address(unsigned long addr);
extern int kernel_text_address(unsigned long addr);
extern int session_of_pgrp(int pgrp);

extern void dump_thread(struct pt_regs *regs, struct user *dump);

#ifdef CONFIG_PRINTK
asmlinkage int vprintk(const char *fmt, va_list args)
	__attribute__ ((format (printf, 1, 0)));
asmlinkage int printk(const char * fmt, ...)
	__attribute__ ((format (printf, 1, 2)));
#else
static inline int vprintk(const char *s, va_list args)
	__attribute__ ((format (printf, 1, 0)));
static inline int vprintk(const char *s, va_list args) { return 0; }
static inline int printk(const char *s, ...)
	__attribute__ ((format (printf, 1, 2)));
static inline int printk(const char *s, ...) { return 0; }
#endif

unsigned long int_sqrt(unsigned long);

static inline int __attribute_pure__ long_log2(unsigned long x)
{
	int r = 0;
	for (x >>= 1; x > 0; x >>= 1)
		r++;
	return r;
}

static inline unsigned long
__attribute_const__ roundup_pow_of_two(unsigned long x)
{
	return 1UL << fls_long(x - 1);
}

extern int printk_ratelimit(void);
extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);

static inline void console_silent(void)
{
	console_loglevel = 0;
}

static inline void console_verbose(void)
{
	if (console_loglevel)
		console_loglevel = 15;
}

extern void bust_spinlocks(int yes);
extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
extern int panic_timeout;
extern int panic_on_oops;
extern int tainted;
extern const char *print_tainted(void);
extern void add_taint(unsigned);

/* Values used for system_state */
extern enum system_states {
	SYSTEM_BOOTING,
	SYSTEM_RUNNING,
	SYSTEM_HALT,
	SYSTEM_POWER_OFF,
	SYSTEM_RESTART,
	SYSTEM_SUSPEND_DISK,
} system_state;

#define TAINT_PROPRIETARY_MODULE	(1<<0)
#define TAINT_FORCED_MODULE		(1<<1)
#define TAINT_UNSAFE_SMP		(1<<2)
#define TAINT_FORCED_RMMOD		(1<<3)
#define TAINT_MACHINE_CHECK		(1<<4)
#define TAINT_BAD_PAGE			(1<<5)

extern void dump_stack(void);

#ifdef DEBUG
#define pr_debug(fmt,arg...) \
	printk(KERN_DEBUG fmt,##arg)
#else
#define pr_debug(fmt,arg...) \
	do { } while (0)
#endif

#define pr_info(fmt,arg...) \
	printk(KERN_INFO fmt,##arg)

/*
 *      Display an IP address in readable format.
 */

#define NIPQUAD(addr) \
	((unsigned char *)&addr)[0], \
	((unsigned char *)&addr)[1], \
	((unsigned char *)&addr)[2], \
	((unsigned char *)&addr)[3]
#define NIPQUAD_FMT "%u.%u.%u.%u"

#define NIP6(addr) \
	ntohs((addr).s6_addr16[0]), \
	ntohs((addr).s6_addr16[1]), \
	ntohs((addr).s6_addr16[2]), \
	ntohs((addr).s6_addr16[3]), \
	ntohs((addr).s6_addr16[4]), \
	ntohs((addr).s6_addr16[5]), \
	ntohs((addr).s6_addr16[6]), \
	ntohs((addr).s6_addr16[7])
#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"

#if defined(__LITTLE_ENDIAN)
#define HIPQUAD(addr) \
	((unsigned char *)&addr)[3], \
	((unsigned char *)&addr)[2], \
	((unsigned char *)&addr)[1], \
	((unsigned char *)&addr)[0]
#elif defined(__BIG_ENDIAN)
#define HIPQUAD	NIPQUAD
#else
#error "Please fix asm/byteorder.h"
#endif /* __LITTLE_ENDIAN */

/*
 * min()/max() macros that also do
 * strict type-checking.. See the
 * "unnecessary" pointer comparison.
 */
#define min(x,y) ({ \
	typeof(x) _x = (x);	\
	typeof(y) _y = (y);	\
	(void) (&_x == &_y);		\
	_x < _y ? _x : _y; })

#define max(x,y) ({ \
	typeof(x) _x = (x);	\
	typeof(y) _y = (y);	\
	(void) (&_x == &_y);		\
	_x > _y ? _x : _y; })

/*
 * ..and if you can't take the strict
 * types, you can specify one yourself.
 *
 * Or not use min/max at all, of course.
 */
#define min_t(type,x,y) \
	({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
#define max_t(type,x,y) \
	({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })


/**
 * container_of - cast a member of a structure out to the containing structure
 * @ptr:	the pointer to the member.
 * @type:	the type of the container struct this is embedded in.
 * @member:	the name of the member within the struct.
 *
 */
#define container_of(ptr, type, member) ({			\
        const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
        (type *)( (char *)__mptr - offsetof(type,member) );})

/*
 * Check at compile time that something is of a particular type.
 * Always evaluates to 1 so you may use it easily in comparisons.
 */
#define typecheck(type,x) \
({	type __dummy; \
	typeof(x) __dummy2; \
	(void)(&__dummy == &__dummy2); \
	1; \
})

/*
 * Check at compile time that 'function' is a certain type, or is a pointer
 * to that type (needs to use typedef for the function type.)
 */
#define typecheck_fn(type,function) \
({	typeof(type) __tmp = function; \
	(void)__tmp; \
})

#endif /* __KERNEL__ */

#define SI_LOAD_SHIFT	16
struct sysinfo {
	long uptime;			/* Seconds since boot */
	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
	unsigned long totalram;		/* Total usable main memory size */
	unsigned long freeram;		/* Available memory size */
	unsigned long sharedram;	/* Amount of shared memory */
	unsigned long bufferram;	/* Memory used by buffers */
	unsigned long totalswap;	/* Total swap space size */
	unsigned long freeswap;		/* swap space still available */
	unsigned short procs;		/* Number of current processes */
	unsigned short pad;		/* explicit padding for m68k */
	unsigned long totalhigh;	/* Total high memory size */
	unsigned long freehigh;		/* Available high memory size */
	unsigned int mem_unit;		/* Memory unit size in bytes */
	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
};

/* Force a compilation error if condition is true */
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))

/* Force a compilation error if condition is true, but also produce a
   result (of value 0 and type size_t), so the expression can be used
   e.g. in a structure initializer (or where-ever else comma expressions
   aren't permitted). */
#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)

/* Trap pasters of __FUNCTION__ at compile-time */
#define __FUNCTION__ (__func__)

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_KERNEL_H
	2	#define _LINUX_KERNEL_H
	3
	4	/*
	5	* 'kernel.h' contains some often-used function prototypes etc
	6	*/
	7
	8	#ifdef __KERNEL__
	9
	10	#include <stdarg.h>
	11	#include <linux/linkage.h>
	12	#include <linux/stddef.h>
	13	#include <linux/types.h>
	14	#include <linux/compiler.h>
	15	#include <linux/bitops.h>
	16	#include <asm/byteorder.h>
	17	#include <asm/bug.h>
	18
	19	extern const char linux_banner[];
	20
	21	#define INT_MAX ((int)(~0U>>1))
	22	#define INT_MIN (-INT_MAX - 1)
	23	#define UINT_MAX (~0U)
	24	#define LONG_MAX ((long)(~0UL>>1))
	25	#define LONG_MIN (-LONG_MAX - 1)
	26	#define ULONG_MAX (~0UL)
111ebb6e OH	27	#define LLONG_MAX ((long long)(~0ULL>>1))
	28	#define LLONG_MIN (-LLONG_MAX - 1)
	29	#define ULLONG_MAX (~0ULL)
1da177e4 LT	30
	31	#define STACK_MAGIC 0xdeadbeef
	32
	33	#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
	34	#define ALIGN(x,a) (((x)+(a)-1)&~((a)-1))
4552d5dc	35	#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
1da177e4 LT	36
	37	#define KERN_EMERG "<0>" /* system is unusable */
	38	#define KERN_ALERT "<1>" /* action must be taken immediately */
	39	#define KERN_CRIT "<2>" /* critical conditions */
	40	#define KERN_ERR "<3>" /* error conditions */
	41	#define KERN_WARNING "<4>" /* warning conditions */
	42	#define KERN_NOTICE "<5>" /* normal but significant condition */
	43	#define KERN_INFO "<6>" /* informational */
	44	#define KERN_DEBUG "<7>" /* debug-level messages */
	45
	46	extern int console_printk[];
	47
	48	#define console_loglevel (console_printk[0])
	49	#define default_message_loglevel (console_printk[1])
	50	#define minimum_console_loglevel (console_printk[2])
	51	#define default_console_loglevel (console_printk[3])
	52
	53	struct completion;
df2e71fb	54	struct pt_regs;
df2e71fb	55	struct user;
1da177e4 LT	56
	57	/**
	58	* might_sleep - annotation for functions that can sleep
	59	*
	60	* this macro will print a stack trace if it is executed in an atomic
	61	* context (spinlock, irq-handler, ...).
	62	*
	63	* This is a useful debugging help to be able to catch problems early and not
	64	* be biten later when the calling function happens to sleep when it is not
	65	* supposed to.
	66	*/
f8cbd99b IM	67	#ifdef CONFIG_PREEMPT_VOLUNTARY
	68	extern int cond_resched(void);
	69	# define might_resched() cond_resched()
	70	#else
	71	# define might_resched() do { } while (0)
	72	#endif
	73
1da177e4	74	#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
f8cbd99b IM	75	void __might_sleep(char *file, int line);
	76	# define might_sleep() \
	77	do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
1da177e4	78	#else
f8cbd99b	79	# define might_sleep() do { might_resched(); } while (0)
1da177e4 LT	80	#endif
1da177e4 LT	81
368a5fa1	82	#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
f8cbd99b	83
1da177e4 LT	84	#define abs(x) ({ \
	85	int __x = (x); \
	86	(__x < 0) ? -__x : __x; \
	87	})
	88
	89	#define labs(x) ({ \
	90	long __x = (x); \
	91	(__x < 0) ? -__x : __x; \
	92	})
	93
e041c683	94	extern struct atomic_notifier_head panic_notifier_list;
1da177e4 LT	95	extern long (*panic_blink)(long time);
	96	NORET_TYPE void panic(const char * fmt, ...)
	97	__attribute__ ((NORET_AND format (printf, 1, 2)));
dd287796 AM	98	extern void oops_enter(void);
	99	extern void oops_exit(void);
	100	extern int oops_may_print(void);
1da177e4 LT	101	fastcall NORET_TYPE void do_exit(long error_code)
	102	ATTRIB_NORET;
	103	NORET_TYPE void complete_and_exit(struct completion *, long)
	104	ATTRIB_NORET;
	105	extern unsigned long simple_strtoul(const char ,char *,unsigned int);
	106	extern long simple_strtol(const char ,char *,unsigned int);
	107	extern unsigned long long simple_strtoull(const char ,char *,unsigned int);
	108	extern long long simple_strtoll(const char ,char *,unsigned int);
	109	extern int sprintf(char * buf, const char * fmt, ...)
	110	__attribute__ ((format (printf, 2, 3)));
	111	extern int vsprintf(char buf, const char , va_list)
	112	__attribute__ ((format (printf, 2, 0)));
	113	extern int snprintf(char * buf, size_t size, const char * fmt, ...)
	114	__attribute__ ((format (printf, 3, 4)));
	115	extern int vsnprintf(char buf, size_t size, const char fmt, va_list args)
	116	__attribute__ ((format (printf, 3, 0)));
	117	extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
	118	__attribute__ ((format (printf, 3, 4)));
	119	extern int vscnprintf(char buf, size_t size, const char fmt, va_list args)
	120	__attribute__ ((format (printf, 3, 0)));
e905914f JF	121	extern char kasprintf(gfp_t gfp, const char fmt, ...)
e905914f JF	122	__attribute__ ((format (printf, 2, 3)));
1da177e4 LT	123
	124	extern int sscanf(const char , const char , ...)
	125	__attribute__ ((format (scanf, 2, 3)));
	126	extern int vsscanf(const char , const char , va_list)
	127	__attribute__ ((format (scanf, 2, 0)));
	128
	129	extern int get_option(char *str, int pint);
	130	extern char get_options(const char str, int nints, int *ints);
	131	extern unsigned long long memparse(char ptr, char *retptr);
	132
5e376613	133	extern int core_kernel_text(unsigned long addr);
1da177e4 LT	134	extern int __kernel_text_address(unsigned long addr);
	135	extern int kernel_text_address(unsigned long addr);
	136	extern int session_of_pgrp(int pgrp);
	137
df2e71fb	138	extern void dump_thread(struct pt_regs regs, struct user dump);
df2e71fb	139
d59745ce	140	#ifdef CONFIG_PRINTK
1da177e4 LT	141	asmlinkage int vprintk(const char *fmt, va_list args)
	142	__attribute__ ((format (printf, 1, 0)));
	143	asmlinkage int printk(const char * fmt, ...)
	144	__attribute__ ((format (printf, 1, 2)));
d59745ce MM	145	#else
	146	static inline int vprintk(const char *s, va_list args)
	147	__attribute__ ((format (printf, 1, 0)));
	148	static inline int vprintk(const char *s, va_list args) { return 0; }
	149	static inline int printk(const char *s, ...)
	150	__attribute__ ((format (printf, 1, 2)));
	151	static inline int printk(const char *s, ...) { return 0; }
	152	#endif
1da177e4 LT	153
	154	unsigned long int_sqrt(unsigned long);
	155
	156	static inline int __attribute_pure__ long_log2(unsigned long x)
	157	{
	158	int r = 0;
	159	for (x >>= 1; x > 0; x >>= 1)
	160	r++;
	161	return r;
	162	}
	163
962749af AM	164	static inline unsigned long
962749af AM	165	__attribute_const__ roundup_pow_of_two(unsigned long x)
1da177e4	166	{
962749af	167	return 1UL << fls_long(x - 1);
1da177e4 LT	168	}
	169
	170	extern int printk_ratelimit(void);
	171	extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
	172
	173	static inline void console_silent(void)
	174	{
	175	console_loglevel = 0;
	176	}
	177
	178	static inline void console_verbose(void)
	179	{
	180	if (console_loglevel)
	181	console_loglevel = 15;
	182	}
	183
	184	extern void bust_spinlocks(int yes);
	185	extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
aa727107	186	extern int panic_timeout;
1da177e4 LT	187	extern int panic_on_oops;
	188	extern int tainted;
	189	extern const char *print_tainted(void);
	190	extern void add_taint(unsigned);
	191
	192	/* Values used for system_state */
	193	extern enum system_states {
	194	SYSTEM_BOOTING,
	195	SYSTEM_RUNNING,
	196	SYSTEM_HALT,
	197	SYSTEM_POWER_OFF,
	198	SYSTEM_RESTART,
729b4d4c	199	SYSTEM_SUSPEND_DISK,
1da177e4 LT	200	} system_state;
	201
	202	#define TAINT_PROPRIETARY_MODULE (1<<0)
	203	#define TAINT_FORCED_MODULE (1<<1)
	204	#define TAINT_UNSAFE_SMP (1<<2)
	205	#define TAINT_FORCED_RMMOD (1<<3)
	206	#define TAINT_MACHINE_CHECK (1<<4)
	207	#define TAINT_BAD_PAGE (1<<5)
	208
	209	extern void dump_stack(void);
	210
	211	#ifdef DEBUG
	212	#define pr_debug(fmt,arg...) \
	213	printk(KERN_DEBUG fmt,##arg)
	214	#else
	215	#define pr_debug(fmt,arg...) \
	216	do { } while (0)
	217	#endif
	218
	219	#define pr_info(fmt,arg...) \
	220	printk(KERN_INFO fmt,##arg)
	221
	222	/*
	223	* Display an IP address in readable format.
	224	*/
	225
	226	#define NIPQUAD(addr) \
	227	((unsigned char *)&addr)[0], \
	228	((unsigned char *)&addr)[1], \
	229	((unsigned char *)&addr)[2], \
	230	((unsigned char *)&addr)[3]
46b86a2d	231	#define NIPQUAD_FMT "%u.%u.%u.%u"
1da177e4 LT	232
	233	#define NIP6(addr) \
	234	ntohs((addr).s6_addr16[0]), \
	235	ntohs((addr).s6_addr16[1]), \
	236	ntohs((addr).s6_addr16[2]), \
	237	ntohs((addr).s6_addr16[3]), \
	238	ntohs((addr).s6_addr16[4]), \
	239	ntohs((addr).s6_addr16[5]), \
	240	ntohs((addr).s6_addr16[6]), \
	241	ntohs((addr).s6_addr16[7])
46b86a2d	242	#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
9343e79a	243	#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
1da177e4 LT	244
	245	#if defined(__LITTLE_ENDIAN)
	246	#define HIPQUAD(addr) \
	247	((unsigned char *)&addr)[3], \
	248	((unsigned char *)&addr)[2], \
	249	((unsigned char *)&addr)[1], \
	250	((unsigned char *)&addr)[0]
	251	#elif defined(__BIG_ENDIAN)
	252	#define HIPQUAD NIPQUAD
	253	#else
	254	#error "Please fix asm/byteorder.h"
	255	#endif /* __LITTLE_ENDIAN */
	256
	257	/*
	258	* min()/max() macros that also do
	259	* strict type-checking.. See the
	260	* "unnecessary" pointer comparison.
	261	*/
	262	#define min(x,y) ({ \
	263	typeof(x) _x = (x); \
	264	typeof(y) _y = (y); \
	265	(void) (&_x == &_y); \
	266	_x < _y ? _x : _y; })
	267
	268	#define max(x,y) ({ \
	269	typeof(x) _x = (x); \
	270	typeof(y) _y = (y); \
	271	(void) (&_x == &_y); \
	272	_x > _y ? _x : _y; })
	273
	274	/*
	275	* ..and if you can't take the strict
	276	* types, you can specify one yourself.
	277	*
	278	* Or not use min/max at all, of course.
	279	*/
	280	#define min_t(type,x,y) \
	281	({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
	282	#define max_t(type,x,y) \
	283	({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
	284
	285
	286	/**
	287	* container_of - cast a member of a structure out to the containing structure
1da177e4 LT	288	* @ptr: the pointer to the member.
	289	* @type: the type of the container struct this is embedded in.
	290	* @member: the name of the member within the struct.
	291	*
	292	*/
	293	#define container_of(ptr, type, member) ({ \
	294	const typeof( ((type )0)->member ) __mptr = (ptr); \
	295	(type )( (char )__mptr - offsetof(type,member) );})
	296
	297	/*
	298	* Check at compile time that something is of a particular type.
	299	* Always evaluates to 1 so you may use it easily in comparisons.
	300	*/
	301	#define typecheck(type,x) \
	302	({ type __dummy; \
	303	typeof(x) __dummy2; \
	304	(void)(&__dummy == &__dummy2); \
	305	1; \
	306	})
	307
711a660d CE	308	/*
	309	* Check at compile time that 'function' is a certain type, or is a pointer
	310	* to that type (needs to use typedef for the function type.)
	311	*/
	312	#define typecheck_fn(type,function) \
	313	({ typeof(type) __tmp = function; \
	314	(void)__tmp; \
	315	})
	316
1da177e4 LT	317	#endif /* __KERNEL__ */
	318
	319	#define SI_LOAD_SHIFT 16
	320	struct sysinfo {
	321	long uptime; /* Seconds since boot */
	322	unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
	323	unsigned long totalram; /* Total usable main memory size */
	324	unsigned long freeram; /* Available memory size */
	325	unsigned long sharedram; /* Amount of shared memory */
	326	unsigned long bufferram; /* Memory used by buffers */
	327	unsigned long totalswap; /* Total swap space size */
	328	unsigned long freeswap; /* swap space still available */
	329	unsigned short procs; /* Number of current processes */
	330	unsigned short pad; /* explicit padding for m68k */
	331	unsigned long totalhigh; /* Total high memory size */
	332	unsigned long freehigh; /* Available high memory size */
	333	unsigned int mem_unit; /* Memory unit size in bytes */
	334	char _f[20-2sizeof(long)-sizeof(int)]; / Padding: libc5 uses this.. */
	335	};
	336
c0398ee6	337	/* Force a compilation error if condition is true */
921717a2	338	#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
1da177e4	339
4552d5dc JB	340	/* Force a compilation error if condition is true, but also produce a
	341	result (of value 0 and type size_t), so the expression can be used
	342	e.g. in a structure initializer (or where-ever else comma expressions
	343	aren't permitted). */
	344	#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
	345
1da177e4	346	/* Trap pasters of __FUNCTION__ at compile-time */
1da177e4	347	#define __FUNCTION__ (__func__)
1da177e4 LT	348
1da177e4 LT	349	#endif