Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759298AbaJ3LQy (ORCPT ); Thu, 30 Oct 2014 07:16:54 -0400 Received: from mail-pa0-f43.google.com ([209.85.220.43]:47498 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759182AbaJ3LQx (ORCPT ); Thu, 30 Oct 2014 07:16:53 -0400 From: "pang.xunlei" To: linux-kernel@vger.kernel.org Cc: rtc-linux@googlegroups.com, xen-devel@lists.xenproject.org, John Stultz , Thomas Gleixner , Alessandro Zummo , Stefano Stabellini , "pang.xunlei" Subject: [RFC PATCH v2 01/11] time: Add do_settimeofday64() safe version(using timespec64) Date: Thu, 30 Oct 2014 19:15:35 +0800 Message-Id: <1414667745-7703-2-git-send-email-pang.xunlei@linaro.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1414667745-7703-1-git-send-email-pang.xunlei@linaro.org> References: <1414667745-7703-1-git-send-email-pang.xunlei@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The kernel uses 32-bit signed value(time_t) for seconds elapsed 1970-01-01:00:00:00, thus it will overflow at 2038-01-19 03:14:08 on 32-bit systems. We call this "2038 safety" issue. As part of addressing 2038 saftey for in-kernel uses, this patch adds safe do_settimeofday64() using timespec64. After this patch, do_settimeofday() should be replaced by do_settimeofday64() one by one. Eventually, do_settimeofday() will be removed from the kernel when it has no users. Signed-off-by: pang.xunlei --- include/linux/timekeeping.h | 1 + kernel/time/timekeeping.c | 34 +++++++++++++++++++++++++--------- 2 files changed, 26 insertions(+), 9 deletions(-) diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 1caa6b0..afc61c3 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -10,6 +10,7 @@ extern int timekeeping_suspended; * Get and set timeofday */ extern void do_gettimeofday(struct timeval *tv); +extern int do_settimeofday64(const struct timespec64 *ts); extern int do_settimeofday(const struct timespec *tv); extern int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index ec1791f..f0dcbc0 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -703,18 +703,19 @@ void do_gettimeofday(struct timeval *tv) EXPORT_SYMBOL(do_gettimeofday); /** - * do_settimeofday - Sets the time of day - * @tv: pointer to the timespec variable containing the new time + * do_settimeofday64 - Sets the time of day + * @ts: pointer to the timespec64 variable containing the new time * * Sets the time of day to the new time and update NTP and notify hrtimers + * Safe version for 2038 safety. */ -int do_settimeofday(const struct timespec *tv) +int do_settimeofday64(const struct timespec64 *ts) { struct timekeeper *tk = &tk_core.timekeeper; - struct timespec64 ts_delta, xt, tmp; + struct timespec64 ts_delta, xt; unsigned long flags; - if (!timespec_valid_strict(tv)) + if (!timespec64_valid_strict(ts)) return -EINVAL; raw_spin_lock_irqsave(&timekeeper_lock, flags); @@ -723,13 +724,12 @@ int do_settimeofday(const struct timespec *tv) timekeeping_forward_now(tk); xt = tk_xtime(tk); - ts_delta.tv_sec = tv->tv_sec - xt.tv_sec; - ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec; + ts_delta.tv_sec = ts->tv_sec - xt.tv_sec; + ts_delta.tv_nsec = ts->tv_nsec - xt.tv_nsec; tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts_delta)); - tmp = timespec_to_timespec64(*tv); - tk_set_xtime(tk, &tmp); + tk_set_xtime(tk, ts); timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET); @@ -741,6 +741,22 @@ int do_settimeofday(const struct timespec *tv) return 0; } +EXPORT_SYMBOL(do_settimeofday64); + +/** + * do_settimeofday - Sets the time of day + * @tv: pointer to the timespec variable containing the new time + * + * Sets the time of day to the new time and update NTP and notify hrtimers + * TODO: [2038 safety] should be replaced by do_settimeofday64(). + */ +int do_settimeofday(const struct timespec *tv) +{ + struct timespec64 ts64; + + ts64 = timespec_to_timespec64(*tv); + return do_settimeofday64(&ts64); +} EXPORT_SYMBOL(do_settimeofday); /** -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/