time64: Add time64.h header and define struct timespec64

# include <linux/cache.h>

# include <linux/seqlock.h>

# include <linux/math64.h>

#include <uapi/linux/time.h>

# include <linux/time64.h>

extern struct timezone sys_tz;

/* Parameters used to convert the timespec values: */

#define MSEC_PER_SEC	1000L

#define USEC_PER_MSEC	1000L

#define NSEC_PER_USEC	1000L

#define NSEC_PER_MSEC	1000000L

#define USEC_PER_SEC	1000000L

#define NSEC_PER_SEC	1000000000L

#define FSEC_PER_SEC	1000000000000000LL

#define TIME_T_MAX	(time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)

/* Located here for timespec_valid_strict */

#define KTIME_MAX			((s64)~((u64)1 << 63))

#define KTIME_SEC_MAX			(KTIME_MAX / NSEC_PER_SEC)

static inline int timespec_equal(const struct timespec *a,

                                 const struct timespec *b)

{

#ifndef _LINUX_TIME64_H

#define _LINUX_TIME64_H

#include <uapi/linux/time.h>

typedef __s64 time64_t;

/*

 * This wants to go into uapi/linux/time.h once we agreed about the

 * userspace interfaces.

 */

#if __BITS_PER_LONG == 64

# define timespec64 timespec

#else

struct timespec64 {

	time64_t	tv_sec;			/* seconds */

	long		tv_nsec;		/* nanoseconds */

};

#endif

/* Parameters used to convert the timespec values: */

#define MSEC_PER_SEC	1000L

#define USEC_PER_MSEC	1000L

#define NSEC_PER_USEC	1000L

#define NSEC_PER_MSEC	1000000L

#define USEC_PER_SEC	1000000L

#define NSEC_PER_SEC	1000000000L

#define FSEC_PER_SEC	1000000000000000LL

/* Located here for timespec[64]_valid_strict */

#define KTIME_MAX			((s64)~((u64)1 << 63))

#define KTIME_SEC_MAX			(KTIME_MAX / NSEC_PER_SEC)

#if __BITS_PER_LONG == 64

# define timespec64_equal		timespec_equal

# define timespec64_compare		timespec_compare

# define set_normalized_timespec64	set_normalized_timespec

# define timespec64_add_safe		timespec_add_safe

# define timespec64_add			timespec_add

# define timespec64_sub			timespec_sub

# define timespec64_valid		timespec_valid

# define timespec64_valid_strict	timespec_valid_strict

# define timespec64_to_ns		timespec_to_ns

# define ns_to_timespec64		ns_to_timespec

# define timespec64_add_ns		timespec_add_ns

#else

static inline int timespec64_equal(const struct timespec64 *a,

				   const struct timespec64 *b)

{

	return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);

}

/*

 * lhs < rhs:  return <0

 * lhs == rhs: return 0

 * lhs > rhs:  return >0

 */

static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs)

{

	if (lhs->tv_sec < rhs->tv_sec)

		return -1;

	if (lhs->tv_sec > rhs->tv_sec)

		return 1;

	return lhs->tv_nsec - rhs->tv_nsec;

}

extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);

/*

 * timespec64_add_safe assumes both values are positive and checks for

 * overflow. It will return TIME_T_MAX if the returned value would be

 * smaller then either of the arguments.

 */

extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,

					 const struct timespec64 rhs);

static inline struct timespec64 timespec64_add(struct timespec64 lhs,

						struct timespec64 rhs)

{

	struct timespec64 ts_delta;

	set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,

				lhs.tv_nsec + rhs.tv_nsec);

	return ts_delta;

}

/*

 * sub = lhs - rhs, in normalized form

 */

static inline struct timespec64 timespec64_sub(struct timespec64 lhs,

						struct timespec64 rhs)

{

	struct timespec64 ts_delta;

	set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,

				lhs.tv_nsec - rhs.tv_nsec);

	return ts_delta;

}

/*

 * Returns true if the timespec64 is norm, false if denorm:

 */

static inline bool timespec64_valid(const struct timespec64 *ts)

{

	/* Dates before 1970 are bogus */

	if (ts->tv_sec < 0)

		return false;

	/* Can't have more nanoseconds then a second */

	if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)

		return false;

	return true;

}

static inline bool timespec64_valid_strict(const struct timespec64 *ts)

{

	if (!timespec64_valid(ts))

		return false;

	/* Disallow values that could overflow ktime_t */

	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)

		return false;

	return true;

}

/**

 * timespec64_to_ns - Convert timespec64 to nanoseconds

 * @ts:		pointer to the timespec64 variable to be converted

 *

 * Returns the scalar nanosecond representation of the timespec64

 * parameter.

 */

static inline s64 timespec64_to_ns(const struct timespec64 *ts)

{

	return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;

}

/**

 * ns_to_timespec64 - Convert nanoseconds to timespec64

 * @nsec:	the nanoseconds value to be converted

 *

 * Returns the timespec64 representation of the nsec parameter.

 */

extern struct timespec64 ns_to_timespec64(const s64 nsec);

/**

 * timespec64_add_ns - Adds nanoseconds to a timespec64

 * @a:		pointer to timespec64 to be incremented

 * @ns:		unsigned nanoseconds value to be added

 *

 * This must always be inlined because its used from the x86-64 vdso,

 * which cannot call other kernel functions.

 */

static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)

{

	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);

	a->tv_nsec = ns;

}

#endif

#endif /* _LINUX_TIME64_H */