diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/timekeeping.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 4f9f65b9132..6262c1d1839 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -387,6 +387,42 @@ int do_settimeofday(const struct timespec *tv) EXPORT_SYMBOL(do_settimeofday); + +/** + * timekeeping_inject_offset - Adds or subtracts from the current time. + * @tv: pointer to the timespec variable containing the offset + * + * Adds or subtracts an offset value from the current time. + */ +int timekeeping_inject_offset(struct timespec *ts) +{ + unsigned long flags; + + if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) + return -EINVAL; + + write_seqlock_irqsave(&xtime_lock, flags); + + timekeeping_forward_now(); + + xtime = timespec_add(xtime, *ts); + wall_to_monotonic = timespec_sub(wall_to_monotonic, *ts); + + timekeeper.ntp_error = 0; + ntp_clear(); + + update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, + timekeeper.mult); + + write_sequnlock_irqrestore(&xtime_lock, flags); + + /* signal hrtimers about time change */ + clock_was_set(); + + return 0; +} +EXPORT_SYMBOL(timekeeping_inject_offset); + /** * change_clocksource - Swaps clocksources if a new one is available * |