include/linux/time64.h

   1 #ifndef _LINUX_TIME64_H
   2 #define _LINUX_TIME64_H
   3
   4 #include <uapi/linux/time.h>
   5 #include <linux/math64.h>
   6
   7 typedef __s64 time64_t;
   8
   9 /*
  10  * This wants to go into uapi/linux/time.h once we agreed about the
  11  * userspace interfaces.
  12  */
  13 #if __BITS_PER_LONG == 64
  14 # define timespec64 timespec
  15 #define itimerspec64 itimerspec
  16 #else
  17 struct timespec64 {
  18         time64_t        tv_sec;                 /* seconds */
  19         long            tv_nsec;                /* nanoseconds */
  20 };
  21
  22 struct itimerspec64 {
  23         struct timespec64 it_interval;
  24         struct timespec64 it_value;
  25 };
  26
  27 #endif
  28
  29 /* Parameters used to convert the timespec values: */
  30 #define MSEC_PER_SEC    1000L
  31 #define USEC_PER_MSEC   1000L
  32 #define NSEC_PER_USEC   1000L
  33 #define NSEC_PER_MSEC   1000000L
  34 #define USEC_PER_SEC    1000000L
  35 #define NSEC_PER_SEC    1000000000L
  36 #define FSEC_PER_SEC    1000000000000000LL
  37
  38 /* Located here for timespec[64]_valid_strict */
  39 #define TIME64_MAX                      ((s64)~((u64)1 << 63))
  40 #define KTIME_MAX                       ((s64)~((u64)1 << 63))
  41 #define KTIME_SEC_MAX                   (KTIME_MAX / NSEC_PER_SEC)
  42
  43 #if __BITS_PER_LONG == 64
  44
  45 static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
  46 {
  47         return ts64;
  48 }
  49
  50 static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
  51 {
  52         return ts;
  53 }
  54
  55 static inline struct itimerspec itimerspec64_to_itimerspec(struct itimerspec64 *its64)
  56 {
  57         return *its64;
  58 }
  59
  60 static inline struct itimerspec64 itimerspec_to_itimerspec64(struct itimerspec *its)
  61 {
  62         return *its;
  63 }
  64
  65 # define timespec64_equal               timespec_equal
  66 # define timespec64_compare             timespec_compare
  67 # define set_normalized_timespec64      set_normalized_timespec
  68 # define timespec64_add                 timespec_add
  69 # define timespec64_sub                 timespec_sub
  70 # define timespec64_valid               timespec_valid
  71 # define timespec64_valid_strict        timespec_valid_strict
  72 # define timespec64_to_ns               timespec_to_ns
  73 # define ns_to_timespec64               ns_to_timespec
  74 # define timespec64_add_ns              timespec_add_ns
  75
  76 #else
  77
  78 static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
  79 {
  80         struct timespec ret;
  81
  82         ret.tv_sec = (time_t)ts64.tv_sec;
  83         ret.tv_nsec = ts64.tv_nsec;
  84         return ret;
  85 }
  86
  87 static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
  88 {
  89         struct timespec64 ret;
  90
  91         ret.tv_sec = ts.tv_sec;
  92         ret.tv_nsec = ts.tv_nsec;
  93         return ret;
  94 }
  95
  96 static inline struct itimerspec itimerspec64_to_itimerspec(struct itimerspec64 *its64)
  97 {
  98         struct itimerspec ret;
  99
 100         ret.it_interval = timespec64_to_timespec(its64->it_interval);
 101         ret.it_value = timespec64_to_timespec(its64->it_value);
 102         return ret;
 103 }
 104
 105 static inline struct itimerspec64 itimerspec_to_itimerspec64(struct itimerspec *its)
 106 {
 107         struct itimerspec64 ret;
 108
 109         ret.it_interval = timespec_to_timespec64(its->it_interval);
 110         ret.it_value = timespec_to_timespec64(its->it_value);
 111         return ret;
 112 }
 113
 114 static inline int timespec64_equal(const struct timespec64 *a,
 115                                    const struct timespec64 *b)
 116 {
 117         return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
 118 }
 119
 120 /*
 121  * lhs < rhs:  return <0
 122  * lhs == rhs: return 0
 123  * lhs > rhs:  return >0
 124  */
 125 static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs)
 126 {
 127         if (lhs->tv_sec < rhs->tv_sec)
 128                 return -1;
 129         if (lhs->tv_sec > rhs->tv_sec)
 130                 return 1;
 131         return lhs->tv_nsec - rhs->tv_nsec;
 132 }
 133
 134 extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);
 135
 136 static inline struct timespec64 timespec64_add(struct timespec64 lhs,
 137                                                 struct timespec64 rhs)
 138 {
 139         struct timespec64 ts_delta;
 140         set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,
 141                                 lhs.tv_nsec + rhs.tv_nsec);
 142         return ts_delta;
 143 }
 144
 145 /*
 146  * sub = lhs - rhs, in normalized form
 147  */
 148 static inline struct timespec64 timespec64_sub(struct timespec64 lhs,
 149                                                 struct timespec64 rhs)
 150 {
 151         struct timespec64 ts_delta;
 152         set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,
 153                                 lhs.tv_nsec - rhs.tv_nsec);
 154         return ts_delta;
 155 }
 156
 157 /*
 158  * Returns true if the timespec64 is norm, false if denorm:
 159  */
 160 static inline bool timespec64_valid(const struct timespec64 *ts)
 161 {
 162         /* Dates before 1970 are bogus */
 163         if (ts->tv_sec < 0)
 164                 return false;
 165         /* Can't have more nanoseconds then a second */
 166         if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
 167                 return false;
 168         return true;
 169 }
 170
 171 static inline bool timespec64_valid_strict(const struct timespec64 *ts)
 172 {
 173         if (!timespec64_valid(ts))
 174                 return false;
 175         /* Disallow values that could overflow ktime_t */
 176         if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
 177                 return false;
 178         return true;
 179 }
 180
 181 /**
 182  * timespec64_to_ns - Convert timespec64 to nanoseconds
 183  * @ts:         pointer to the timespec64 variable to be converted
 184  *
 185  * Returns the scalar nanosecond representation of the timespec64
 186  * parameter.
 187  */
 188 static inline s64 timespec64_to_ns(const struct timespec64 *ts)
 189 {
 190         return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
 191 }
 192
 193 /**
 194  * ns_to_timespec64 - Convert nanoseconds to timespec64
 195  * @nsec:       the nanoseconds value to be converted
 196  *
 197  * Returns the timespec64 representation of the nsec parameter.
 198  */
 199 extern struct timespec64 ns_to_timespec64(const s64 nsec);
 200
 201 /**
 202  * timespec64_add_ns - Adds nanoseconds to a timespec64
 203  * @a:          pointer to timespec64 to be incremented
 204  * @ns:         unsigned nanoseconds value to be added
 205  *
 206  * This must always be inlined because its used from the x86-64 vdso,
 207  * which cannot call other kernel functions.
 208  */
 209 static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
 210 {
 211         a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
 212         a->tv_nsec = ns;
 213 }
 214
 215 #endif
 216
 217 /*
 218  * timespec64_add_safe assumes both values are positive and checks for
 219  * overflow. It will return TIME64_MAX in case of overflow.
 220  */
 221 extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
 222                                          const struct timespec64 rhs);
 223
 224 #endif /* _LINUX_TIME64_H */