Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : #ifndef _LINUX_TIME64_H
       3             : #define _LINUX_TIME64_H
       4             : 
       5             : #include <linux/math64.h>
       6             : #include <vdso/time64.h>
       7             : 
       8             : typedef __s64 time64_t;
       9             : typedef __u64 timeu64_t;
      10             : 
      11             : #include <uapi/linux/time.h>
      12             : 
      13             : struct timespec64 {
      14             :         time64_t        tv_sec;                 /* seconds */
      15             :         long            tv_nsec;                /* nanoseconds */
      16             : };
      17             : 
      18             : struct itimerspec64 {
      19             :         struct timespec64 it_interval;
      20             :         struct timespec64 it_value;
      21             : };
      22             : 
      23             : /* Located here for timespec[64]_valid_strict */
      24             : #define TIME64_MAX                      ((s64)~((u64)1 << 63))
      25             : #define TIME64_MIN                      (-TIME64_MAX - 1)
      26             : 
      27             : #define KTIME_MAX                       ((s64)~((u64)1 << 63))
      28             : #define KTIME_SEC_MAX                   (KTIME_MAX / NSEC_PER_SEC)
      29             : 
      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             : 
      41       33970 : static inline int timespec64_equal(const struct timespec64 *a,
      42             :                                    const struct timespec64 *b)
      43             : {
      44       24444 :         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       88775 : static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs)
      53             : {
      54       46357 :         if (lhs->tv_sec < rhs->tv_sec)
      55             :                 return -1;
      56        4154 :         if (lhs->tv_sec > rhs->tv_sec)
      57             :                 return 1;
      58        4090 :         return lhs->tv_nsec - rhs->tv_nsec;
      59             : }
      60             : 
      61             : extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);
      62             : 
      63           0 : static inline struct timespec64 timespec64_add(struct timespec64 lhs,
      64             :                                                 struct timespec64 rhs)
      65             : {
      66           0 :         struct timespec64 ts_delta;
      67           0 :         set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,
      68           0 :                                 lhs.tv_nsec + rhs.tv_nsec);
      69           0 :         return ts_delta;
      70             : }
      71             : 
      72             : /*
      73             :  * sub = lhs - rhs, in normalized form
      74             :  */
      75         514 : static inline struct timespec64 timespec64_sub(struct timespec64 lhs,
      76             :                                                 struct timespec64 rhs)
      77             : {
      78         514 :         struct timespec64 ts_delta;
      79         513 :         set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,
      80         514 :                                 lhs.tv_nsec - rhs.tv_nsec);
      81         514 :         return ts_delta;
      82             : }
      83             : 
      84             : /*
      85             :  * Returns true if the timespec64 is norm, false if denorm:
      86             :  */
      87         857 : static inline bool timespec64_valid(const struct timespec64 *ts)
      88             : {
      89             :         /* Dates before 1970 are bogus */
      90         857 :         if (ts->tv_sec < 0)
      91             :                 return false;
      92             :         /* Can't have more nanoseconds then a second */
      93         857 :         if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
      94             :                 return false;
      95             :         return true;
      96             : }
      97             : 
      98           0 : static inline bool timespec64_valid_strict(const struct timespec64 *ts)
      99             : {
     100           0 :         if (!timespec64_valid(ts))
     101             :                 return false;
     102             :         /* Disallow values that could overflow ktime_t */
     103           0 :         if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
     104             :                 return false;
     105             :         return true;
     106             : }
     107             : 
     108           1 : static inline bool timespec64_valid_settod(const struct timespec64 *ts)
     109             : {
     110           3 :         if (!timespec64_valid(ts))
     111             :                 return false;
     112             :         /* Disallow values which cause overflow issues vs. CLOCK_REALTIME */
     113           1 :         if ((unsigned long long)ts->tv_sec >= TIME_SETTOD_SEC_MAX)
     114             :                 return false;
     115             :         return true;
     116             : }
     117             : 
     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           1 : static inline s64 timespec64_to_ns(const struct timespec64 *ts)
     126             : {
     127             :         /* Prevent multiplication overflow */
     128           0 :         if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
     129             :                 return KTIME_MAX;
     130             : 
     131           1 :         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        1144 : static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
     151             : {
     152        1144 :         a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
     153        1144 :         a->tv_nsec = ns;
     154             : }
     155             : 
     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             : 
     163             : #endif /* _LINUX_TIME64_H */