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/* 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 */
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