From c2c11ae4b6bc03b41720337028b940cbec9e316f Mon Sep 17 00:00:00 2001 From: "pang.xunlei" Date: Tue, 18 Nov 2014 19:15:19 +0800 Subject: rtc/lib: Provide y2038 safe rtc_tm_to_time()/rtc_time_to_tm() replacement As part of addressing "y2038 problem" for in-kernel uses, this patch adds safe rtc_tm_to_time64()/rtc_time64_to_tm() respectively using time64_t. After this patch, rtc_tm_to_time() is deprecated and all its call sites will be fixed using corresponding safe versions, it can be removed when having no users. Also change rtc_tm_to_time64() to return time64_t directly instead of just as a parameter like rtc_tm_to_time() does. After this patch, rtc_time_to_tm() is deprecated and all its call sites will be fixed using corresponding safe versions, it can be removed when having no users. In addition, change rtc_tm_to_ktime() and rtc_ktime_to_tm() to use the safe version in passing. Signed-off-by: pang.xunlei Signed-off-by: John Stultz --- drivers/rtc/rtc-lib.c | 38 ++++++++++++++++++++------------------ include/linux/rtc.h | 21 +++++++++++++++++++-- 2 files changed, 39 insertions(+), 20 deletions(-) diff --git a/drivers/rtc/rtc-lib.c b/drivers/rtc/rtc-lib.c index c4cf05731118..e6bfb9c42a10 100644 --- a/drivers/rtc/rtc-lib.c +++ b/drivers/rtc/rtc-lib.c @@ -45,16 +45,20 @@ int rtc_year_days(unsigned int day, unsigned int month, unsigned int year) } EXPORT_SYMBOL(rtc_year_days); + /* + * rtc_time_to_tm64 - Converts time64_t to rtc_time. * Convert seconds since 01-01-1970 00:00:00 to Gregorian date. */ -void rtc_time_to_tm(unsigned long time, struct rtc_time *tm) +void rtc_time64_to_tm(time64_t time, struct rtc_time *tm) { unsigned int month, year; + unsigned long secs; int days; - days = time / 86400; - time -= (unsigned int) days * 86400; + /* time must be positive */ + days = div_s64(time, 86400); + secs = time - (unsigned int) days * 86400; /* day of the week, 1970-01-01 was a Thursday */ tm->tm_wday = (days + 4) % 7; @@ -81,14 +85,14 @@ void rtc_time_to_tm(unsigned long time, struct rtc_time *tm) tm->tm_mon = month; tm->tm_mday = days + 1; - tm->tm_hour = time / 3600; - time -= tm->tm_hour * 3600; - tm->tm_min = time / 60; - tm->tm_sec = time - tm->tm_min * 60; + tm->tm_hour = secs / 3600; + secs -= tm->tm_hour * 3600; + tm->tm_min = secs / 60; + tm->tm_sec = secs - tm->tm_min * 60; tm->tm_isdst = 0; } -EXPORT_SYMBOL(rtc_time_to_tm); +EXPORT_SYMBOL(rtc_time64_to_tm); /* * Does the rtc_time represent a valid date/time? @@ -109,24 +113,22 @@ int rtc_valid_tm(struct rtc_time *tm) EXPORT_SYMBOL(rtc_valid_tm); /* + * rtc_tm_to_time64 - Converts rtc_time to time64_t. * Convert Gregorian date to seconds since 01-01-1970 00:00:00. */ -int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time) +time64_t rtc_tm_to_time64(struct rtc_time *tm) { - *time = mktime(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, + return mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); - return 0; } -EXPORT_SYMBOL(rtc_tm_to_time); +EXPORT_SYMBOL(rtc_tm_to_time64); /* * Convert rtc_time to ktime */ ktime_t rtc_tm_to_ktime(struct rtc_time tm) { - time_t time; - rtc_tm_to_time(&tm, &time); - return ktime_set(time, 0); + return ktime_set(rtc_tm_to_time64(&tm), 0); } EXPORT_SYMBOL_GPL(rtc_tm_to_ktime); @@ -135,14 +137,14 @@ EXPORT_SYMBOL_GPL(rtc_tm_to_ktime); */ struct rtc_time rtc_ktime_to_tm(ktime_t kt) { - struct timespec ts; + struct timespec64 ts; struct rtc_time ret; - ts = ktime_to_timespec(kt); + ts = ktime_to_timespec64(kt); /* Round up any ns */ if (ts.tv_nsec) ts.tv_sec++; - rtc_time_to_tm(ts.tv_sec, &ret); + rtc_time64_to_tm(ts.tv_sec, &ret); return ret; } EXPORT_SYMBOL_GPL(rtc_ktime_to_tm); diff --git a/include/linux/rtc.h b/include/linux/rtc.h index c2c28975293c..6d6be09a2fe5 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -19,11 +19,28 @@ extern int rtc_month_days(unsigned int month, unsigned int year); extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year); extern int rtc_valid_tm(struct rtc_time *tm); -extern int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time); -extern void rtc_time_to_tm(unsigned long time, struct rtc_time *tm); +extern time64_t rtc_tm_to_time64(struct rtc_time *tm); +extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm); ktime_t rtc_tm_to_ktime(struct rtc_time tm); struct rtc_time rtc_ktime_to_tm(ktime_t kt); +/** + * Deprecated. Use rtc_time64_to_tm(). + */ +static inline void rtc_time_to_tm(unsigned long time, struct rtc_time *tm) +{ + rtc_time64_to_tm(time, tm); +} + +/** + * Deprecated. Use rtc_tm_to_time64(). + */ +static inline int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time) +{ + *time = rtc_tm_to_time64(tm); + + return 0; +} #include #include -- cgit v1.2.3