From 916c7a855174e3b53d182b97a26b2e27a29726a1 Mon Sep 17 00:00:00 2001 From: Roman Zippel Date: Wed, 20 Aug 2008 16:46:08 -0700 Subject: ntp: fix ADJ_OFFSET_SS_READ bug and do_adjtimex() cleanup Thanks to the review by Michael Kerrisk a bug in the recent ADJ_OFFSET_SS_READ option was discovered, where the ntp time_offset was inadvertently set by it. This fixes this by making the adjtime code more separate from the ntp_adjtime code (both of which really want to be separate syscalls). Signed-off-by: Roman Zippel Signed-off-by: Andrew Morton Acked-by: John Stultz Signed-off-by: Ingo Molnar --- include/linux/timex.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include/linux/timex.h') diff --git a/include/linux/timex.h b/include/linux/timex.h index fc6035d29d5..c00bcdd3ae4 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -141,8 +141,15 @@ struct timex { #define ADJ_MICRO 0x1000 /* select microsecond resolution */ #define ADJ_NANO 0x2000 /* select nanosecond resolution */ #define ADJ_TICK 0x4000 /* tick value */ + +#ifdef __KERNEL__ +#define ADJ_ADJTIME 0x8000 /* switch between adjtime/adjtimex modes */ +#define ADJ_OFFSET_SINGLESHOT 0x0001 /* old-fashioned adjtime */ +#define ADJ_OFFSET_READONLY 0x2000 /* read-only adjtime */ +#else #define ADJ_OFFSET_SINGLESHOT 0x8001 /* old-fashioned adjtime */ -#define ADJ_OFFSET_SS_READ 0xa001 /* read-only adjtime */ +#define ADJ_OFFSET_SS_READ 0xa001 /* read-only adjtime */ +#endif /* xntp 3.4 compatibility names */ #define MOD_OFFSET ADJ_OFFSET -- cgit v1.2.3-70-g09d2 From d40e944c25fb4642adb2a4c580a48218a9f3f824 Mon Sep 17 00:00:00 2001 From: Roman Zippel Date: Mon, 22 Sep 2008 14:42:44 -0700 Subject: ntp: improve adjtimex frequency rounding Change PPM_SCALE_INV_SHIFT so that it doesn't throw away any input bits (19 is the amount of the factor 2 in PPM_SCALE), the output frequency can then be calculated back to its input value, as the inverse divide produce a slightly larger value, which is then correctly rounded by the final shift. Reported-by: Martin Ziegler Signed-off-by: Roman Zippel Cc: John Stultz Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner --- include/linux/timex.h | 2 +- kernel/time/ntp.c | 5 ++--- 2 files changed, 3 insertions(+), 4 deletions(-) (limited to 'include/linux/timex.h') diff --git a/include/linux/timex.h b/include/linux/timex.h index c00bcdd3ae4..9007313b5b7 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -82,7 +82,7 @@ */ #define SHIFT_USEC 16 /* frequency offset scale (shift) */ #define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC)) -#define PPM_SCALE_INV_SHIFT 20 +#define PPM_SCALE_INV_SHIFT 19 #define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \ PPM_SCALE + 1) diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 450a45cb01c..ddb0465a6ba 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -406,9 +406,8 @@ adj_done: if (time_status & (STA_UNSYNC|STA_CLOCKERR)) result = TIME_ERROR; - txc->freq = shift_right((s32)(time_freq >> PPM_SCALE_INV_SHIFT) * - (s64)PPM_SCALE_INV, - NTP_SCALE_SHIFT); + txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * + (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT); txc->maxerror = time_maxerror; txc->esterror = time_esterror; txc->status = time_status; -- cgit v1.2.3-70-g09d2