From 2ee966320028ac846654eba5344540eeb4dc228d Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Wed, 1 Apr 2015 20:34:22 -0700 Subject: [PATCH] time: Add y2038 safe read_persistent_clock64() As part of addressing in-kernel y2038 issues, this patch adds read_persistent_clock64() and replaces all the call sites of read_persistent_clock() with this function. This is a __weak implementation, which simply calls the existing y2038 unsafe read_persistent_clock(). This allows architecture specific implementations to be converted independently, and eventually the y2038 unsafe read_persistent_clock() can be removed after all its architecture specific implementations have been converted to read_persistent_clock64(). Suggested-by: Arnd Bergmann Signed-off-by: Xunlei Pang Signed-off-by: John Stultz Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1427945681-29972-3-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar --- arch/mips/lasat/sysctl.c | 4 ++-- include/linux/timekeeping.h | 1 + kernel/time/timekeeping.c | 22 ++++++++++++---------- 3 files changed, 15 insertions(+), 12 deletions(-) diff --git a/arch/mips/lasat/sysctl.c b/arch/mips/lasat/sysctl.c index 3b7f65cc4218..cf9b4633257e 100644 --- a/arch/mips/lasat/sysctl.c +++ b/arch/mips/lasat/sysctl.c @@ -75,11 +75,11 @@ static int rtctmp; int proc_dolasatrtc(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { - struct timespec ts; + struct timespec64 ts; int r; if (!write) { - read_persistent_clock(&ts); + read_persistent_clock64(&ts); rtctmp = ts.tv_sec; /* check for time < 0 and set to 0 */ if (rtctmp < 0) diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 18d27a3f72ca..4c0f76f4616c 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -268,6 +268,7 @@ static inline bool has_persistent_clock(void) } extern void read_persistent_clock(struct timespec *ts); +extern void read_persistent_clock64(struct timespec64 *ts); extern void read_boot_clock(struct timespec *ts); extern void read_boot_clock64(struct timespec64 *ts); extern int update_persistent_clock(struct timespec now); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 652e50a9c6ed..b1dbfa573dce 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1173,6 +1173,14 @@ void __weak read_persistent_clock(struct timespec *ts) ts->tv_nsec = 0; } +void __weak read_persistent_clock64(struct timespec64 *ts64) +{ + struct timespec ts; + + read_persistent_clock(&ts); + *ts64 = timespec_to_timespec64(ts); +} + /** * read_boot_clock - Return time of the system start. * @@ -1205,10 +1213,8 @@ void __init timekeeping_init(void) struct clocksource *clock; unsigned long flags; struct timespec64 now, boot, tmp; - struct timespec ts; - read_persistent_clock(&ts); - now = timespec_to_timespec64(ts); + read_persistent_clock64(&now); if (!timespec64_valid_strict(&now)) { pr_warn("WARNING: Persistent clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); @@ -1278,7 +1284,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, * timekeeping_inject_sleeptime64 - Adds suspend interval to timeekeeping values * @delta: pointer to a timespec64 delta value * - * This hook is for architectures that cannot support read_persistent_clock + * This hook is for architectures that cannot support read_persistent_clock64 * because their RTC/persistent clock is only accessible when irqs are enabled. * * This function should only be called by rtc_resume(), and allows @@ -1325,12 +1331,10 @@ void timekeeping_resume(void) struct clocksource *clock = tk->tkr_mono.clock; unsigned long flags; struct timespec64 ts_new, ts_delta; - struct timespec tmp; cycle_t cycle_now, cycle_delta; bool suspendtime_found = false; - read_persistent_clock(&tmp); - ts_new = timespec_to_timespec64(tmp); + read_persistent_clock64(&ts_new); clockevents_resume(); clocksource_resume(); @@ -1406,10 +1410,8 @@ int timekeeping_suspend(void) unsigned long flags; struct timespec64 delta, delta_delta; static struct timespec64 old_delta; - struct timespec tmp; - read_persistent_clock(&tmp); - timekeeping_suspend_time = timespec_to_timespec64(tmp); + read_persistent_clock64(&timekeeping_suspend_time); /* * On some systems the persistent_clock can not be detected at -- 2.20.1