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author | John Stultz <john.stultz@linaro.org> | 2014-07-17 01:03:58 +0400 |
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committer | John Stultz <john.stultz@linaro.org> | 2014-07-23 21:17:53 +0400 |
commit | 361a3bf00582469877f8d18ff20f1efa6b781274 (patch) | |
tree | 8ee505002fe5b839728b16a054590d2b44b8be1b /include/linux/time64.h | |
parent | b17b20d70dcbe48dd1aa6aba073a60ddfce5d7db (diff) | |
download | linux-361a3bf00582469877f8d18ff20f1efa6b781274.tar.xz |
time64: Add time64.h header and define struct timespec64
Define the timespec64 structure and standard helper functions.
[ tglx: Make it 32bit only. 64bit really can map timespec to timespec64 ]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Diffstat (limited to 'include/linux/time64.h')
-rw-r--r-- | include/linux/time64.h | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/include/linux/time64.h b/include/linux/time64.h new file mode 100644 index 000000000000..e7b499e1cd79 --- /dev/null +++ b/include/linux/time64.h @@ -0,0 +1,162 @@ +#ifndef _LINUX_TIME64_H +#define _LINUX_TIME64_H + +#include <uapi/linux/time.h> + +typedef __s64 time64_t; + +/* + * This wants to go into uapi/linux/time.h once we agreed about the + * userspace interfaces. + */ +#if __BITS_PER_LONG == 64 +# define timespec64 timespec +#else +struct timespec64 { + time64_t tv_sec; /* seconds */ + long tv_nsec; /* nanoseconds */ +}; +#endif + +/* Parameters used to convert the timespec values: */ +#define MSEC_PER_SEC 1000L +#define USEC_PER_MSEC 1000L +#define NSEC_PER_USEC 1000L +#define NSEC_PER_MSEC 1000000L +#define USEC_PER_SEC 1000000L +#define NSEC_PER_SEC 1000000000L +#define FSEC_PER_SEC 1000000000000000LL + +/* Located here for timespec[64]_valid_strict */ +#define KTIME_MAX ((s64)~((u64)1 << 63)) +#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC) + +#if __BITS_PER_LONG == 64 + +# define timespec64_equal timespec_equal +# define timespec64_compare timespec_compare +# define set_normalized_timespec64 set_normalized_timespec +# define timespec64_add_safe timespec_add_safe +# define timespec64_add timespec_add +# define timespec64_sub timespec_sub +# define timespec64_valid timespec_valid +# define timespec64_valid_strict timespec_valid_strict +# define timespec64_to_ns timespec_to_ns +# define ns_to_timespec64 ns_to_timespec +# define timespec64_add_ns timespec_add_ns + +#else + +static inline int timespec64_equal(const struct timespec64 *a, + const struct timespec64 *b) +{ + return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec); +} + +/* + * lhs < rhs: return <0 + * lhs == rhs: return 0 + * lhs > rhs: return >0 + */ +static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs) +{ + if (lhs->tv_sec < rhs->tv_sec) + return -1; + if (lhs->tv_sec > rhs->tv_sec) + return 1; + return lhs->tv_nsec - rhs->tv_nsec; +} + +extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec); + +/* + * timespec64_add_safe assumes both values are positive and checks for + * overflow. It will return TIME_T_MAX if the returned value would be + * smaller then either of the arguments. + */ +extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs, + const struct timespec64 rhs); + + +static inline struct timespec64 timespec64_add(struct timespec64 lhs, + struct timespec64 rhs) +{ + struct timespec64 ts_delta; + set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec, + lhs.tv_nsec + rhs.tv_nsec); + return ts_delta; +} + +/* + * sub = lhs - rhs, in normalized form + */ +static inline struct timespec64 timespec64_sub(struct timespec64 lhs, + struct timespec64 rhs) +{ + struct timespec64 ts_delta; + set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec, + lhs.tv_nsec - rhs.tv_nsec); + return ts_delta; +} + +/* + * Returns true if the timespec64 is norm, false if denorm: + */ +static inline bool timespec64_valid(const struct timespec64 *ts) +{ + /* Dates before 1970 are bogus */ + if (ts->tv_sec < 0) + return false; + /* Can't have more nanoseconds then a second */ + if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) + return false; + return true; +} + +static inline bool timespec64_valid_strict(const struct timespec64 *ts) +{ + if (!timespec64_valid(ts)) + return false; + /* Disallow values that could overflow ktime_t */ + if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX) + return false; + return true; +} + +/** + * timespec64_to_ns - Convert timespec64 to nanoseconds + * @ts: pointer to the timespec64 variable to be converted + * + * Returns the scalar nanosecond representation of the timespec64 + * parameter. + */ +static inline s64 timespec64_to_ns(const struct timespec64 *ts) +{ + return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; +} + +/** + * ns_to_timespec64 - Convert nanoseconds to timespec64 + * @nsec: the nanoseconds value to be converted + * + * Returns the timespec64 representation of the nsec parameter. + */ +extern struct timespec64 ns_to_timespec64(const s64 nsec); + +/** + * timespec64_add_ns - Adds nanoseconds to a timespec64 + * @a: pointer to timespec64 to be incremented + * @ns: unsigned nanoseconds value to be added + * + * This must always be inlined because its used from the x86-64 vdso, + * which cannot call other kernel functions. + */ +static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns) +{ + a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns); + a->tv_nsec = ns; +} + +#endif + +#endif /* _LINUX_TIME64_H */ |