1 #ifndef _LINUX_TIME_H 2 #define _LINUX_TIME_H 3 4 # include <linux/cache.h> 5 # include <linux/seqlock.h> 6 # include <linux/math64.h> 7 # include <linux/time64.h> 8 9 extern struct timezone sys_tz; 10 11 #define TIME_T_MAX (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1) 12 13 static inline int timespec_equal(const struct timespec *a, 14 const struct timespec *b) 15 { 16 return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec); 17 } 18 19 /* 20 * lhs < rhs: return <0 21 * lhs == rhs: return 0 22 * lhs > rhs: return >0 23 */ 24 static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs) 25 { 26 if (lhs->tv_sec < rhs->tv_sec) 27 return -1; 28 if (lhs->tv_sec > rhs->tv_sec) 29 return 1; 30 return lhs->tv_nsec - rhs->tv_nsec; 31 } 32 33 static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs) 34 { 35 if (lhs->tv_sec < rhs->tv_sec) 36 return -1; 37 if (lhs->tv_sec > rhs->tv_sec) 38 return 1; 39 return lhs->tv_usec - rhs->tv_usec; 40 } 41 42 extern unsigned long mktime(const unsigned int year, const unsigned int mon, 43 const unsigned int day, const unsigned int hour, 44 const unsigned int min, const unsigned int sec); 45 46 extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec); 47 48 /* 49 * timespec_add_safe assumes both values are positive and checks 50 * for overflow. It will return TIME_T_MAX if the reutrn would be 51 * smaller then either of the arguments. 52 */ 53 extern struct timespec timespec_add_safe(const struct timespec lhs, 54 const struct timespec rhs); 55 56 57 static inline struct timespec timespec_add(struct timespec lhs, 58 struct timespec rhs) 59 { 60 struct timespec ts_delta; 61 set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec, 62 lhs.tv_nsec + rhs.tv_nsec); 63 return ts_delta; 64 } 65 66 /* 67 * sub = lhs - rhs, in normalized form 68 */ 69 static inline struct timespec timespec_sub(struct timespec lhs, 70 struct timespec rhs) 71 { 72 struct timespec ts_delta; 73 set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec, 74 lhs.tv_nsec - rhs.tv_nsec); 75 return ts_delta; 76 } 77 78 /* 79 * Returns true if the timespec is norm, false if denorm: 80 */ 81 static inline bool timespec_valid(const struct timespec *ts) 82 { 83 /* Dates before 1970 are bogus */ 84 if (ts->tv_sec < 0) 85 return false; 86 /* Can't have more nanoseconds then a second */ 87 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) 88 return false; 89 return true; 90 } 91 92 static inline bool timespec_valid_strict(const struct timespec *ts) 93 { 94 if (!timespec_valid(ts)) 95 return false; 96 /* Disallow values that could overflow ktime_t */ 97 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX) 98 return false; 99 return true; 100 } 101 102 extern struct timespec timespec_trunc(struct timespec t, unsigned gran); 103 104 #define CURRENT_TIME (current_kernel_time()) 105 #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 }) 106 107 /* Some architectures do not supply their own clocksource. 108 * This is mainly the case in architectures that get their 109 * inter-tick times by reading the counter on their interval 110 * timer. Since these timers wrap every tick, they're not really 111 * useful as clocksources. Wrapping them to act like one is possible 112 * but not very efficient. So we provide a callout these arches 113 * can implement for use with the jiffies clocksource to provide 114 * finer then tick granular time. 115 */ 116 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET 117 extern u32 (*arch_gettimeoffset)(void); 118 #endif 119 120 struct itimerval; 121 extern int do_setitimer(int which, struct itimerval *value, 122 struct itimerval *ovalue); 123 extern int do_getitimer(int which, struct itimerval *value); 124 125 extern unsigned int alarm_setitimer(unsigned int seconds); 126 127 extern long do_utimes(int dfd, const char __user *filename, struct timespec *times, int flags); 128 129 struct tms; 130 extern void do_sys_times(struct tms *); 131 132 /* 133 * Similar to the struct tm in userspace <time.h>, but it needs to be here so 134 * that the kernel source is self contained. 135 */ 136 struct tm { 137 /* 138 * the number of seconds after the minute, normally in the range 139 * 0 to 59, but can be up to 60 to allow for leap seconds 140 */ 141 int tm_sec; 142 /* the number of minutes after the hour, in the range 0 to 59*/ 143 int tm_min; 144 /* the number of hours past midnight, in the range 0 to 23 */ 145 int tm_hour; 146 /* the day of the month, in the range 1 to 31 */ 147 int tm_mday; 148 /* the number of months since January, in the range 0 to 11 */ 149 int tm_mon; 150 /* the number of years since 1900 */ 151 long tm_year; 152 /* the number of days since Sunday, in the range 0 to 6 */ 153 int tm_wday; 154 /* the number of days since January 1, in the range 0 to 365 */ 155 int tm_yday; 156 }; 157 158 void time_to_tm(time_t totalsecs, int offset, struct tm *result); 159 160 /** 161 * timespec_to_ns - Convert timespec to nanoseconds 162 * @ts: pointer to the timespec variable to be converted 163 * 164 * Returns the scalar nanosecond representation of the timespec 165 * parameter. 166 */ 167 static inline s64 timespec_to_ns(const struct timespec *ts) 168 { 169 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; 170 } 171 172 /** 173 * timeval_to_ns - Convert timeval to nanoseconds 174 * @ts: pointer to the timeval variable to be converted 175 * 176 * Returns the scalar nanosecond representation of the timeval 177 * parameter. 178 */ 179 static inline s64 timeval_to_ns(const struct timeval *tv) 180 { 181 return ((s64) tv->tv_sec * NSEC_PER_SEC) + 182 tv->tv_usec * NSEC_PER_USEC; 183 } 184 185 /** 186 * ns_to_timespec - Convert nanoseconds to timespec 187 * @nsec: the nanoseconds value to be converted 188 * 189 * Returns the timespec representation of the nsec parameter. 190 */ 191 extern struct timespec ns_to_timespec(const s64 nsec); 192 193 /** 194 * ns_to_timeval - Convert nanoseconds to timeval 195 * @nsec: the nanoseconds value to be converted 196 * 197 * Returns the timeval representation of the nsec parameter. 198 */ 199 extern struct timeval ns_to_timeval(const s64 nsec); 200 201 /** 202 * timespec_add_ns - Adds nanoseconds to a timespec 203 * @a: pointer to timespec 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 timespec_add_ns(struct timespec *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