From 094aa1881fdc1b8889b442eb3511b31f3ec2b762 Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Tue, 1 Feb 2011 13:52:20 +0000 Subject: [PATCH] ntp: Add ADJ_SETOFFSET mode bit This patch adds a new mode bit into the timex structure. When set, the bit instructs the kernel to add the given time value to the current time. Signed-off-by: Richard Cochran Acked-by: John Stultz LKML-Reference: <20110201134320.688829863@linutronix.de> Signed-off-by: Thomas Gleixner --- include/linux/timex.h | 3 ++- kernel/time/ntp.c | 11 +++++++++++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/include/linux/timex.h b/include/linux/timex.h index d23999f9499..aa60fe7b6ed 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -73,7 +73,7 @@ struct timex { long tolerance; /* clock frequency tolerance (ppm) * (read only) */ - struct timeval time; /* (read only) */ + struct timeval time; /* (read only, except for ADJ_SETOFFSET) */ long tick; /* (modified) usecs between clock ticks */ long ppsfreq; /* pps frequency (scaled ppm) (ro) */ @@ -102,6 +102,7 @@ struct timex { #define ADJ_STATUS 0x0010 /* clock status */ #define ADJ_TIMECONST 0x0020 /* pll time constant */ #define ADJ_TAI 0x0080 /* set TAI offset */ +#define ADJ_SETOFFSET 0x0100 /* add 'time' to current time */ #define ADJ_MICRO 0x1000 /* select microsecond resolution */ #define ADJ_NANO 0x2000 /* select nanosecond resolution */ #define ADJ_TICK 0x4000 /* tick value */ diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index ed8cfdf1698..5ac593267a2 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -648,6 +648,17 @@ int do_adjtimex(struct timex *txc) hrtimer_cancel(&leap_timer); } + if (txc->modes & ADJ_SETOFFSET) { + struct timespec delta; + if ((unsigned long)txc->time.tv_usec >= NSEC_PER_SEC) + return -EINVAL; + delta.tv_sec = txc->time.tv_sec; + delta.tv_nsec = txc->time.tv_usec; + if (!(txc->modes & ADJ_NANO)) + delta.tv_nsec *= 1000; + timekeeping_inject_offset(&delta); + } + getnstimeofday(&ts); write_seqlock_irq(&xtime_lock); -- 2.20.1