LXR linux/include/linux/time.h

   1#ifndef _LINUX_TIME_H
   2#define _LINUX_TIME_H
   3
   4#include <linux/types.h>
   5
   6#ifdef __KERNEL__
   7# include <linux/cache.h>
   8# include <linux/seqlock.h>
   9# include <linux/math64.h>
  10#endif
  11
  12#ifndef _STRUCT_TIMESPEC
  13#define _STRUCT_TIMESPEC
  14struct timespec {
  15        __kernel_time_t tv_sec;                 /* seconds */
  16        long            tv_nsec;                /* nanoseconds */
  17};
  18#endif
  19
  20struct timeval {
  21        __kernel_time_t         tv_sec;         /* seconds */
  22        __kernel_suseconds_t    tv_usec;        /* microseconds */
  23};
  24
  25struct timezone {
  26        int     tz_minuteswest; /* minutes west of Greenwich */
  27        int     tz_dsttime;     /* type of dst correction */
  28};
  29
  30#ifdef __KERNEL__
  31
  32extern struct timezone sys_tz;
  33
  34/* Parameters used to convert the timespec values: */
  35#define MSEC_PER_SEC    1000L
  36#define USEC_PER_MSEC   1000L
  37#define NSEC_PER_USEC   1000L
  38#define NSEC_PER_MSEC   1000000L
  39#define USEC_PER_SEC    1000000L
  40#define NSEC_PER_SEC    1000000000L
  41#define FSEC_PER_SEC    1000000000000000LL
  42
  43#define TIME_T_MAX      (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
  44
  45static inline int timespec_equal(const struct timespec *a,
  46                                 const struct timespec *b)
  47{
  48        return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
  49}
  50
  51/*
  52 * lhs < rhs:  return <0
  53 * lhs == rhs: return 0
  54 * lhs > rhs:  return >0
  55 */
  56static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
  57{
  58        if (lhs->tv_sec < rhs->tv_sec)
  59                return -1;
  60        if (lhs->tv_sec > rhs->tv_sec)
  61                return 1;
  62        return lhs->tv_nsec - rhs->tv_nsec;
  63}
  64
  65static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs)
  66{
  67        if (lhs->tv_sec < rhs->tv_sec)
  68                return -1;
  69        if (lhs->tv_sec > rhs->tv_sec)
  70                return 1;
  71        return lhs->tv_usec - rhs->tv_usec;
  72}
  73
  74extern unsigned long mktime(const unsigned int year, const unsigned int mon,
  75                            const unsigned int day, const unsigned int hour,
  76                            const unsigned int min, const unsigned int sec);
  77
  78extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
  79
  80/*
  81 * timespec_add_safe assumes both values are positive and checks
  82 * for overflow. It will return TIME_T_MAX if the reutrn would be
  83 * smaller then either of the arguments.
  84 */
  85extern struct timespec timespec_add_safe(const struct timespec lhs,
  86                                         const struct timespec rhs);
  87
  88
  89static inline struct timespec timespec_add(struct timespec lhs,
  90                                                struct timespec rhs)
  91{
  92        struct timespec ts_delta;
  93        set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
  94                                lhs.tv_nsec + rhs.tv_nsec);
  95        return ts_delta;
  96}
  97
  98/*
  99 * sub = lhs - rhs, in normalized form
 100 */
 101static inline struct timespec timespec_sub(struct timespec lhs,
 102                                                struct timespec rhs)
 103{
 104        struct timespec ts_delta;
 105        set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
 106                                lhs.tv_nsec - rhs.tv_nsec);
 107        return ts_delta;
 108}
 109
 110/*
 111 * Returns true if the timespec is norm, false if denorm:
 112 */
 113#define timespec_valid(ts) \
 114        (((ts)->tv_sec >= 0) && (((unsigned long) (ts)->tv_nsec) < NSEC_PER_SEC))
 115
 116extern void read_persistent_clock(struct timespec *ts);
 117extern void read_boot_clock(struct timespec *ts);
 118extern int update_persistent_clock(struct timespec now);
 119extern int no_sync_cmos_clock __read_mostly;
 120void timekeeping_init(void);
 121extern int timekeeping_suspended;
 122
 123unsigned long get_seconds(void);
 124struct timespec current_kernel_time(void);
 125struct timespec __current_kernel_time(void); /* does not take xtime_lock */
 126struct timespec get_monotonic_coarse(void);
 127void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
 128                                struct timespec *wtom, struct timespec *sleep);
 129void timekeeping_inject_sleeptime(struct timespec *delta);
 130
 131#define CURRENT_TIME            (current_kernel_time())
 132#define CURRENT_TIME_SEC        ((struct timespec) { get_seconds(), 0 })
 133
 134/* Some architectures do not supply their own clocksource.
 135 * This is mainly the case in architectures that get their
 136 * inter-tick times by reading the counter on their interval
 137 * timer. Since these timers wrap every tick, they're not really
 138 * useful as clocksources. Wrapping them to act like one is possible
 139 * but not very efficient. So we provide a callout these arches
 140 * can implement for use with the jiffies clocksource to provide
 141 * finer then tick granular time.
 142 */
 143#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
 144extern u32 arch_gettimeoffset(void);
 145#else
 146static inline u32 arch_gettimeoffset(void) { return 0; }
 147#endif
 148
 149extern void do_gettimeofday(struct timeval *tv);
 150extern int do_settimeofday(const struct timespec *tv);
 151extern int do_sys_settimeofday(const struct timespec *tv,
 152                               const struct timezone *tz);
 153#define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
 154extern long do_utimes(int dfd, const char __user *filename, struct timespec *times, int flags);
 155struct itimerval;
 156extern int do_setitimer(int which, struct itimerval *value,
 157                        struct itimerval *ovalue);
 158extern unsigned int alarm_setitimer(unsigned int seconds);
 159extern int do_getitimer(int which, struct itimerval *value);
 160extern void getnstimeofday(struct timespec *tv);
 161extern void getrawmonotonic(struct timespec *ts);
 162extern void getnstime_raw_and_real(struct timespec *ts_raw,
 163                struct timespec *ts_real);
 164extern void getboottime(struct timespec *ts);
 165extern void monotonic_to_bootbased(struct timespec *ts);
 166extern void get_monotonic_boottime(struct timespec *ts);
 167
 168extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
 169extern int timekeeping_valid_for_hres(void);
 170extern u64 timekeeping_max_deferment(void);
 171extern void timekeeping_leap_insert(int leapsecond);
 172extern int timekeeping_inject_offset(struct timespec *ts);
 173
 174struct tms;
 175extern void do_sys_times(struct tms *);
 176
 177/*
 178 * Similar to the struct tm in userspace <time.h>, but it needs to be here so
 179 * that the kernel source is self contained.
 180 */
 181struct tm {
 182        /*
 183         * the number of seconds after the minute, normally in the range
 184         * 0 to 59, but can be up to 60 to allow for leap seconds
 185         */
 186        int tm_sec;
 187        /* the number of minutes after the hour, in the range 0 to 59*/
 188        int tm_min;
 189        /* the number of hours past midnight, in the range 0 to 23 */
 190        int tm_hour;
 191        /* the day of the month, in the range 1 to 31 */
 192        int tm_mday;
 193        /* the number of months since January, in the range 0 to 11 */
 194        int tm_mon;
 195        /* the number of years since 1900 */
 196        long tm_year;
 197        /* the number of days since Sunday, in the range 0 to 6 */
 198        int tm_wday;
 199        /* the number of days since January 1, in the range 0 to 365 */
 200        int tm_yday;
 201};
 202
 203void time_to_tm(time_t totalsecs, int offset, struct tm *result);
 204
 205/**
 206 * timespec_to_ns - Convert timespec to nanoseconds
 207 * @ts:         pointer to the timespec variable to be converted
 208 *
 209 * Returns the scalar nanosecond representation of the timespec
 210 * parameter.
 211 */
 212static inline s64 timespec_to_ns(const struct timespec *ts)
 213{
 214        return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
 215}
 216
 217/**
 218 * timeval_to_ns - Convert timeval to nanoseconds
 219 * @ts:         pointer to the timeval variable to be converted
 220 *
 221 * Returns the scalar nanosecond representation of the timeval
 222 * parameter.
 223 */
 224static inline s64 timeval_to_ns(const struct timeval *tv)
 225{
 226        return ((s64) tv->tv_sec * NSEC_PER_SEC) +
 227                tv->tv_usec * NSEC_PER_USEC;
 228}
 229
 230/**
 231 * ns_to_timespec - Convert nanoseconds to timespec
 232 * @nsec:       the nanoseconds value to be converted
 233 *
 234 * Returns the timespec representation of the nsec parameter.
 235 */
 236extern struct timespec ns_to_timespec(const s64 nsec);
 237
 238/**
 239 * ns_to_timeval - Convert nanoseconds to timeval
 240 * @nsec:       the nanoseconds value to be converted
 241 *
 242 * Returns the timeval representation of the nsec parameter.
 243 */
 244extern struct timeval ns_to_timeval(const s64 nsec);
 245
 246/**
 247 * timespec_add_ns - Adds nanoseconds to a timespec
 248 * @a:          pointer to timespec to be incremented
 249 * @ns:         unsigned nanoseconds value to be added
 250 *
 251 * This must always be inlined because its used from the x86-64 vdso,
 252 * which cannot call other kernel functions.
 253 */
 254static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
 255{
 256        a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
 257        a->tv_nsec = ns;
 258}
 259#endif /* __KERNEL__ */
 260
 261#define NFDBITS                 __NFDBITS
 262
 263#define FD_SETSIZE              __FD_SETSIZE
 264#define FD_SET(fd,fdsetp)       __FD_SET(fd,fdsetp)
 265#define FD_CLR(fd,fdsetp)       __FD_CLR(fd,fdsetp)
 266#define FD_ISSET(fd,fdsetp)     __FD_ISSET(fd,fdsetp)
 267#define FD_ZERO(fdsetp)         __FD_ZERO(fdsetp)
 268
 269/*
 270 * Names of the interval timers, and structure
 271 * defining a timer setting:
 272 */
 273#define ITIMER_REAL             0
 274#define ITIMER_VIRTUAL          1
 275#define ITIMER_PROF             2
 276
 277struct itimerspec {
 278        struct timespec it_interval;    /* timer period */
 279        struct timespec it_value;       /* timer expiration */
 280};
 281
 282struct itimerval {
 283        struct timeval it_interval;     /* timer interval */
 284        struct timeval it_value;        /* current value */
 285};
 286
 287/*
 288 * The IDs of the various system clocks (for POSIX.1b interval timers):
 289 */
 290#define CLOCK_REALTIME                  0
 291#define CLOCK_MONOTONIC                 1
 292#define CLOCK_PROCESS_CPUTIME_ID        2
 293#define CLOCK_THREAD_CPUTIME_ID         3
 294#define CLOCK_MONOTONIC_RAW             4
 295#define CLOCK_REALTIME_COARSE           5
 296#define CLOCK_MONOTONIC_COARSE          6
 297#define CLOCK_BOOTTIME                  7
 298#define CLOCK_REALTIME_ALARM            8
 299#define CLOCK_BOOTTIME_ALARM            9
 300
 301/*
 302 * The IDs of various hardware clocks:
 303 */
 304#define CLOCK_SGI_CYCLE                 10
 305#define MAX_CLOCKS                      16
 306#define CLOCKS_MASK                     (CLOCK_REALTIME | CLOCK_MONOTONIC)
 307#define CLOCKS_MONO                     CLOCK_MONOTONIC
 308
 309/*
 310 * The various flags for setting POSIX.1b interval timers:
 311 */
 312#define TIMER_ABSTIME                   0x01
 313
 314#endif
 315