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 time64_t mktime64(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 /** 47 * Deprecated. Use mktime64(). 48 */ 49 static inline unsigned long mktime(const unsigned int year, 50 const unsigned int mon, const unsigned int day, 51 const unsigned int hour, const unsigned int min, 52 const unsigned int sec) 53 { 54 return mktime64(year, mon, day, hour, min, sec); 55 } 56 57 extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec); 58 59 /* 60 * timespec_add_safe assumes both values are positive and checks 61 * for overflow. It will return TIME_T_MAX if the reutrn would be 62 * smaller then either of the arguments. 63 */ 64 extern struct timespec timespec_add_safe(const struct timespec lhs, 65 const struct timespec rhs); 66 67 68 static inline struct timespec timespec_add(struct timespec lhs, 69 struct timespec rhs) 70 { 71 struct timespec ts_delta; 72 set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec, 73 lhs.tv_nsec + rhs.tv_nsec); 74 return ts_delta; 75 } 76 77 /* 78 * sub = lhs - rhs, in normalized form 79 */ 80 static inline struct timespec timespec_sub(struct timespec lhs, 81 struct timespec rhs) 82 { 83 struct timespec ts_delta; 84 set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec, 85 lhs.tv_nsec - rhs.tv_nsec); 86 return ts_delta; 87 } 88 89 /* 90 * Returns true if the timespec is norm, false if denorm: 91 */ 92 static inline bool timespec_valid(const struct timespec *ts) 93 { 94 /* Dates before 1970 are bogus */ 95 if (ts->tv_sec < 0) 96 return false; 97 /* Can't have more nanoseconds then a second */ 98 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) 99 return false; 100 return true; 101 } 102 103 static inline bool timespec_valid_strict(const struct timespec *ts) 104 { 105 if (!timespec_valid(ts)) 106 return false; 107 /* Disallow values that could overflow ktime_t */ 108 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX) 109 return false; 110 return true; 111 } 112 113 static inline bool timeval_valid(const struct timeval *tv) 114 { 115 /* Dates before 1970 are bogus */ 116 if (tv->tv_sec < 0) 117 return false; 118 119 /* Can't have more microseconds then a second */ 120 if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC) 121 return false; 122 123 return true; 124 } 125 126 extern struct timespec timespec_trunc(struct timespec t, unsigned gran); 127 128 /* 129 * Validates if a timespec/timeval used to inject a time offset is valid. 130 * Offsets can be postive or negative. The value of the timeval/timespec 131 * is the sum of its fields, but *NOTE*: the field tv_usec/tv_nsec must 132 * always be non-negative. 133 */ 134 static inline bool timeval_inject_offset_valid(const struct timeval *tv) 135 { 136 /* We don't check the tv_sec as it can be positive or negative */ 137 138 /* Can't have more microseconds then a second */ 139 if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC) 140 return false; 141 return true; 142 } 143 144 static inline bool timespec_inject_offset_valid(const struct timespec *ts) 145 { 146 /* We don't check the tv_sec as it can be positive or negative */ 147 148 /* Can't have more nanoseconds then a second */ 149 if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC) 150 return false; 151 return true; 152 } 153 154 /* Some architectures do not supply their own clocksource. 155 * This is mainly the case in architectures that get their 156 * inter-tick times by reading the counter on their interval 157 * timer. Since these timers wrap every tick, they're not really 158 * useful as clocksources. Wrapping them to act like one is possible 159 * but not very efficient. So we provide a callout these arches 160 * can implement for use with the jiffies clocksource to provide 161 * finer then tick granular time. 162 */ 163 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET 164 extern u32 (*arch_gettimeoffset)(void); 165 #endif 166 167 struct itimerval; 168 extern int do_setitimer(int which, struct itimerval *value, 169 struct itimerval *ovalue); 170 extern int do_getitimer(int which, struct itimerval *value); 171 172 extern long do_utimes(int dfd, const char __user *filename, struct timespec *times, int flags); 173 174 /* 175 * Similar to the struct tm in userspace <time.h>, but it needs to be here so 176 * that the kernel source is self contained. 177 */ 178 struct tm { 179 /* 180 * the number of seconds after the minute, normally in the range 181 * 0 to 59, but can be up to 60 to allow for leap seconds 182 */ 183 int tm_sec; 184 /* the number of minutes after the hour, in the range 0 to 59*/ 185 int tm_min; 186 /* the number of hours past midnight, in the range 0 to 23 */ 187 int tm_hour; 188 /* the day of the month, in the range 1 to 31 */ 189 int tm_mday; 190 /* the number of months since January, in the range 0 to 11 */ 191 int tm_mon; 192 /* the number of years since 1900 */ 193 long tm_year; 194 /* the number of days since Sunday, in the range 0 to 6 */ 195 int tm_wday; 196 /* the number of days since January 1, in the range 0 to 365 */ 197 int tm_yday; 198 }; 199 200 void time64_to_tm(time64_t totalsecs, int offset, struct tm *result); 201 202 /** 203 * time_to_tm - converts the calendar time to local broken-down time 204 * 205 * @totalsecs the number of seconds elapsed since 00:00:00 on January 1, 1970, 206 * Coordinated Universal Time (UTC). 207 * @offset offset seconds adding to totalsecs. 208 * @result pointer to struct tm variable to receive broken-down time 209 */ 210 static inline void time_to_tm(time_t totalsecs, int offset, struct tm *result) 211 { 212 time64_to_tm(totalsecs, offset, result); 213 } 214 215 /** 216 * timespec_to_ns - Convert timespec to nanoseconds 217 * @ts: pointer to the timespec variable to be converted 218 * 219 * Returns the scalar nanosecond representation of the timespec 220 * parameter. 221 */ 222 static inline s64 timespec_to_ns(const struct timespec *ts) 223 { 224 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; 225 } 226 227 /** 228 * timeval_to_ns - Convert timeval to nanoseconds 229 * @ts: pointer to the timeval variable to be converted 230 * 231 * Returns the scalar nanosecond representation of the timeval 232 * parameter. 233 */ 234 static inline s64 timeval_to_ns(const struct timeval *tv) 235 { 236 return ((s64) tv->tv_sec * NSEC_PER_SEC) + 237 tv->tv_usec * NSEC_PER_USEC; 238 } 239 240 /** 241 * ns_to_timespec - Convert nanoseconds to timespec 242 * @nsec: the nanoseconds value to be converted 243 * 244 * Returns the timespec representation of the nsec parameter. 245 */ 246 extern struct timespec ns_to_timespec(const s64 nsec); 247 248 /** 249 * ns_to_timeval - Convert nanoseconds to timeval 250 * @nsec: the nanoseconds value to be converted 251 * 252 * Returns the timeval representation of the nsec parameter. 253 */ 254 extern struct timeval ns_to_timeval(const s64 nsec); 255 256 /** 257 * timespec_add_ns - Adds nanoseconds to a timespec 258 * @a: pointer to timespec to be incremented 259 * @ns: unsigned nanoseconds value to be added 260 * 261 * This must always be inlined because its used from the x86-64 vdso, 262 * which cannot call other kernel functions. 263 */ 264 static __always_inline void timespec_add_ns(struct timespec *a, u64 ns) 265 { 266 a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns); 267 a->tv_nsec = ns; 268 } 269 270 #endif 271