[mirror_ubuntu-jammy-kernel.git] / include / linux / time64.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_TIME64_H
#define _LINUX_TIME64_H

#include <linux/math64.h>
#include <vdso/time64.h>

typedef __s64 time64_t;
typedef __u64 timeu64_t;

#include <uapi/linux/time.h>

struct timespec64 {
	time64_t	tv_sec;			/* seconds */
	long		tv_nsec;		/* nanoseconds */
};

struct itimerspec64 {
	struct timespec64 it_interval;
	struct timespec64 it_value;
};

/* Located here for timespec[64]_valid_strict */
#define TIME64_MAX			((s64)~((u64)1 << 63))
#define TIME64_MIN			(-TIME64_MAX - 1)

#define KTIME_MAX			((s64)~((u64)1 << 63))
#define KTIME_SEC_MAX			(KTIME_MAX / NSEC_PER_SEC)

/*
 * Limits for settimeofday():
 *
 * To prevent setting the time close to the wraparound point time setting
 * is limited so a reasonable uptime can be accomodated. Uptime of 30 years
 * should be really sufficient, which means the cutoff is 2232. At that
 * point the cutoff is just a small part of the larger problem.
 */
#define TIME_UPTIME_SEC_MAX		(30LL * 365 * 24 *3600)
#define TIME_SETTOD_SEC_MAX		(KTIME_SEC_MAX - TIME_UPTIME_SEC_MAX)

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);

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;
}

static inline bool timespec64_valid_settod(const struct timespec64 *ts)
{
	if (!timespec64_valid(ts))
		return false;
	/* Disallow values which cause overflow issues vs. CLOCK_REALTIME */
	if ((unsigned long long)ts->tv_sec >= TIME_SETTOD_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)
{
	/* Prevent multiplication overflow */
	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
		return KTIME_MAX;

	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;
}

/*
 * timespec64_add_safe assumes both values are positive and checks for
 * overflow. It will return TIME64_MAX in case of overflow.
 */
extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
					 const struct timespec64 rhs);

#endif /* _LINUX_TIME64_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
361a3bf0 JS	2	#ifndef _LINUX_TIME64_H
	3	#define _LINUX_TIME64_H
	4
30f3b3f9	5	#include <linux/math64.h>
b72a9c5e	6	#include <vdso/time64.h>
361a3bf0 JS	7
361a3bf0 JS	8	typedef __s64 time64_t;
469e857f	9	typedef __u64 timeu64_t;
361a3bf0	10
acf8870a DD	11	#include <uapi/linux/time.h>
acf8870a DD	12
361a3bf0 JS	13	struct timespec64 {
	14	time64_t tv_sec; /* seconds */
	15	long tv_nsec; /* nanoseconds */
	16	};
19a46fe5 BW	17
	18	struct itimerspec64 {
	19	struct timespec64 it_interval;
	20	struct timespec64 it_value;
	21	};
	22
361a3bf0	23	/* Located here for timespec[64]_valid_strict */
833f32d7	24	#define TIME64_MAX ((s64)~((u64)1 << 63))
188d20bc DD	25	#define TIME64_MIN (-TIME64_MAX - 1)
188d20bc DD	26
361a3bf0 JS	27	#define KTIME_MAX ((s64)~((u64)1 << 63))
	28	#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
	29
7a8e61f8 TG	30	/*
	31	* Limits for settimeofday():
	32	*
	33	* To prevent setting the time close to the wraparound point time setting
	34	* is limited so a reasonable uptime can be accomodated. Uptime of 30 years
	35	* should be really sufficient, which means the cutoff is 2232. At that
	36	* point the cutoff is just a small part of the larger problem.
	37	*/
	38	#define TIME_UPTIME_SEC_MAX (30LL * 365 * 24 *3600)
	39	#define TIME_SETTOD_SEC_MAX (KTIME_SEC_MAX - TIME_UPTIME_SEC_MAX)
	40
361a3bf0 JS	41	static inline int timespec64_equal(const struct timespec64 *a,
	42	const struct timespec64 *b)
	43	{
	44	return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
	45	}
	46
	47	/*
	48	* lhs < rhs: return <0
	49	* lhs == rhs: return 0
	50	* lhs > rhs: return >0
	51	*/
	52	static inline int timespec64_compare(const struct timespec64 lhs, const struct timespec64 rhs)
	53	{
	54	if (lhs->tv_sec < rhs->tv_sec)
	55	return -1;
	56	if (lhs->tv_sec > rhs->tv_sec)
	57	return 1;
	58	return lhs->tv_nsec - rhs->tv_nsec;
	59	}
	60
	61	extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);
	62
361a3bf0 JS	63	static inline struct timespec64 timespec64_add(struct timespec64 lhs,
	64	struct timespec64 rhs)
	65	{
	66	struct timespec64 ts_delta;
	67	set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,
	68	lhs.tv_nsec + rhs.tv_nsec);
	69	return ts_delta;
	70	}
	71
	72	/*
	73	* sub = lhs - rhs, in normalized form
	74	*/
	75	static inline struct timespec64 timespec64_sub(struct timespec64 lhs,
	76	struct timespec64 rhs)
	77	{
	78	struct timespec64 ts_delta;
	79	set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,
	80	lhs.tv_nsec - rhs.tv_nsec);
	81	return ts_delta;
	82	}
	83
	84	/*
	85	* Returns true if the timespec64 is norm, false if denorm:
	86	*/
	87	static inline bool timespec64_valid(const struct timespec64 *ts)
	88	{
	89	/* Dates before 1970 are bogus */
	90	if (ts->tv_sec < 0)
	91	return false;
	92	/* Can't have more nanoseconds then a second */
	93	if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
	94	return false;
	95	return true;
	96	}
	97
	98	static inline bool timespec64_valid_strict(const struct timespec64 *ts)
	99	{
	100	if (!timespec64_valid(ts))
	101	return false;
	102	/* Disallow values that could overflow ktime_t */
	103	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
	104	return false;
	105	return true;
	106	}
	107
7a8e61f8 TG	108	static inline bool timespec64_valid_settod(const struct timespec64 *ts)
	109	{
	110	if (!timespec64_valid(ts))
	111	return false;
	112	/* Disallow values which cause overflow issues vs. CLOCK_REALTIME */
	113	if ((unsigned long long)ts->tv_sec >= TIME_SETTOD_SEC_MAX)
	114	return false;
	115	return true;
	116	}
	117
361a3bf0 JS	118	/**
	119	* timespec64_to_ns - Convert timespec64 to nanoseconds
	120	* @ts: pointer to the timespec64 variable to be converted
	121	*
	122	* Returns the scalar nanosecond representation of the timespec64
	123	* parameter.
	124	*/
	125	static inline s64 timespec64_to_ns(const struct timespec64 *ts)
	126	{
cb477557 ZT	127	/* Prevent multiplication overflow */
	128	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
	129	return KTIME_MAX;
	130
361a3bf0 JS	131	return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
	132	}
	133
	134	/**
	135	* ns_to_timespec64 - Convert nanoseconds to timespec64
	136	* @nsec: the nanoseconds value to be converted
	137	*
	138	* Returns the timespec64 representation of the nsec parameter.
	139	*/
	140	extern struct timespec64 ns_to_timespec64(const s64 nsec);
	141
	142	/**
	143	* timespec64_add_ns - Adds nanoseconds to a timespec64
	144	* @a: pointer to timespec64 to be incremented
	145	* @ns: unsigned nanoseconds value to be added
	146	*
	147	* This must always be inlined because its used from the x86-64 vdso,
	148	* which cannot call other kernel functions.
	149	*/
	150	static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
	151	{
	152	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
	153	a->tv_nsec = ns;
	154	}
	155
8e4f70e2 DD	156	/*
	157	* timespec64_add_safe assumes both values are positive and checks for
	158	* overflow. It will return TIME64_MAX in case of overflow.
	159	*/
	160	extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
	161	const struct timespec64 rhs);
	162
361a3bf0	163	#endif /* _LINUX_TIME64_H */