Merge branch 'fortglx/4.15/time' of https://git.linaro.org/people/john.stultz/linux into timers/core

Pull timekeeping updates from John Stultz:

 - More y2038 work from Arnd Bergmann

 - A new mechanism to allow RTC drivers to specify the resolution of the
   RTC so the suspend/resume code can make informed decisions whether to
   inject the suspended time or not in case of fast suspend/resume cycles.

drivers/rtc/class.c

@@ -161,6 +161,9 @@ static struct rtc_device *rtc_allocate_device(void)
 
 	device_initialize(&rtc->dev);
 
+	/* Drivers can revise this default after allocating the device. */
+	rtc->set_offset_nsec =  NSEC_PER_SEC / 2;
+
 	rtc->irq_freq = 1;
 	rtc->max_user_freq = 64;
 	rtc->dev.class = rtc_class;

drivers/rtc/systohc.c

@@ -10,6 +10,7 @@
 /**
  * rtc_set_ntp_time - Save NTP synchronized time to the RTC
  * @now: Current time of day
+ * @target_nsec: pointer for desired now->tv_nsec value
  *
  * Replacement for the NTP platform function update_persistent_clock64
  * that stores time for later retrieval by rtc_hctosys.
@@ -18,30 +19,52 @@
  * possible at all, and various other -errno for specific temporary failure
  * cases.
  *
+ * -EPROTO is returned if now.tv_nsec is not close enough to *target_nsec.
+ (
  * If temporary failure is indicated the caller should try again 'soon'
  */
-int rtc_set_ntp_time(struct timespec64 now)
+int rtc_set_ntp_time(struct timespec64 now, unsigned long *target_nsec)
 {
 	struct rtc_device *rtc;
 	struct rtc_time tm;
+	struct timespec64 to_set;
 	int err = -ENODEV;
-
-	if (now.tv_nsec < (NSEC_PER_SEC >> 1))
-		rtc_time64_to_tm(now.tv_sec, &tm);
-	else
-		rtc_time64_to_tm(now.tv_sec + 1, &tm);
+	bool ok;
 
 	rtc = rtc_class_open(CONFIG_RTC_SYSTOHC_DEVICE);
-	if (rtc) {
-		/* rtc_hctosys exclusively uses UTC, so we call set_time here,
-		 * not set_mmss. */
-		if (rtc->ops &&
-		    (rtc->ops->set_time ||
-		     rtc->ops->set_mmss64 ||
-		     rtc->ops->set_mmss))
-			err = rtc_set_time(rtc, &tm);
-		rtc_class_close(rtc);
+	if (!rtc)
+		goto out_err;
+
+	if (!rtc->ops || (!rtc->ops->set_time && !rtc->ops->set_mmss64 &&
+			  !rtc->ops->set_mmss))
+		goto out_close;
+
+	/* Compute the value of tv_nsec we require the caller to supply in
+	 * now.tv_nsec.  This is the value such that (now +
+	 * set_offset_nsec).tv_nsec == 0.
+	 */
+	set_normalized_timespec64(&to_set, 0, -rtc->set_offset_nsec);
+	*target_nsec = to_set.tv_nsec;
+
+	/* The ntp code must call this with the correct value in tv_nsec, if
+	 * it does not we update target_nsec and return EPROTO to make the ntp
+	 * code try again later.
+	 */
+	ok = rtc_tv_nsec_ok(rtc->set_offset_nsec, &to_set, &now);
+	if (!ok) {
+		err = -EPROTO;
+		goto out_close;
 	}
 
+	rtc_time64_to_tm(to_set.tv_sec, &tm);
+
+	/* rtc_hctosys exclusively uses UTC, so we call set_time here, not
+	 * set_mmss.
+	 */
+	err = rtc_set_time(rtc, &tm);
+
+out_close:
+	rtc_class_close(rtc);
+out_err:
 	return err;
 }

include/linux/ktime.h

@@ -270,5 +270,6 @@ static inline ktime_t ms_to_ktime(u64 ms)
 }
 
 # include <linux/timekeeping.h>
+# include <linux/timekeeping32.h>
 
 #endif

include/linux/rtc.h

@@ -135,6 +135,14 @@ struct rtc_device {
 	/* Some hardware can't support UIE mode */
 	int uie_unsupported;
 
+	/* Number of nsec it takes to set the RTC clock. This influences when
+	 * the set ops are called. An offset:
+	 *   - of 0.5 s will call RTC set for wall clock time 10.0 s at 9.5 s
+	 *   - of 1.5 s will call RTC set for wall clock time 10.0 s at 8.5 s
+	 *   - of -0.5 s will call RTC set for wall clock time 10.0 s at 10.5 s
+	 */
+	long set_offset_nsec;
+
 	bool registered;
 
 	struct nvmem_config *nvmem_config;
@@ -172,7 +180,7 @@ extern void devm_rtc_device_unregister(struct device *dev,
 
 extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
-extern int rtc_set_ntp_time(struct timespec64 now);
+extern int rtc_set_ntp_time(struct timespec64 now, unsigned long *target_nsec);
 int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
 extern int rtc_read_alarm(struct rtc_device *rtc,
 			struct rtc_wkalrm *alrm);
@@ -221,6 +229,39 @@ static inline bool is_leap_year(unsigned int year)
 	return (!(year % 4) && (year % 100)) || !(year % 400);
 }
 
+/* Determine if we can call to driver to set the time. Drivers can only be
+ * called to set a second aligned time value, and the field set_offset_nsec
+ * specifies how far away from the second aligned time to call the driver.
+ *
+ * This also computes 'to_set' which is the time we are trying to set, and has
+ * a zero in tv_nsecs, such that:
+ *    to_set - set_delay_nsec == now +/- FUZZ
+ *
+ */
+static inline bool rtc_tv_nsec_ok(s64 set_offset_nsec,
+				  struct timespec64 *to_set,
+				  const struct timespec64 *now)
+{
+	/* Allowed error in tv_nsec, arbitarily set to 5 jiffies in ns. */
+	const unsigned long TIME_SET_NSEC_FUZZ = TICK_NSEC * 5;
+	struct timespec64 delay = {.tv_sec = 0,
+				   .tv_nsec = set_offset_nsec};
+
+	*to_set = timespec64_add(*now, delay);
+
+	if (to_set->tv_nsec < TIME_SET_NSEC_FUZZ) {
+		to_set->tv_nsec = 0;
+		return true;
+	}
+
+	if (to_set->tv_nsec > NSEC_PER_SEC - TIME_SET_NSEC_FUZZ) {
+		to_set->tv_sec++;
+		to_set->tv_nsec = 0;
+		return true;
+	}
+	return false;
+}
+
 #define rtc_register_device(device) \
 	__rtc_register_device(THIS_MODULE, device)
 

include/linux/time.h

@@ -17,149 +17,10 @@ int get_itimerspec64(struct itimerspec64 *it,
 int put_itimerspec64(const struct itimerspec64 *it,
 			struct itimerspec __user *uit);
 
-#define TIME_T_MAX	(time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
-
-static inline int timespec_equal(const struct timespec *a,
-                                 const struct timespec *b)
-{
-	return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
-}
-
-/*
- * lhs < rhs:  return <0
- * lhs == rhs: return 0
- * lhs > rhs:  return >0
- */
-static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
-{
-	if (lhs->tv_sec < rhs->tv_sec)
-		return -1;
-	if (lhs->tv_sec > rhs->tv_sec)
-		return 1;
-	return lhs->tv_nsec - rhs->tv_nsec;
-}
-
-static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs)
-{
-	if (lhs->tv_sec < rhs->tv_sec)
-		return -1;
-	if (lhs->tv_sec > rhs->tv_sec)
-		return 1;
-	return lhs->tv_usec - rhs->tv_usec;
-}
-
 extern time64_t mktime64(const unsigned int year, const unsigned int mon,
 			const unsigned int day, const unsigned int hour,
 			const unsigned int min, const unsigned int sec);
 
-/**
- * Deprecated. Use mktime64().
- */
-static inline unsigned long mktime(const unsigned int year,
-			const unsigned int mon, const unsigned int day,
-			const unsigned int hour, const unsigned int min,
-			const unsigned int sec)
-{
-	return mktime64(year, mon, day, hour, min, sec);
-}
-
-extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
-
-/*
- * timespec_add_safe assumes both values are positive and checks
- * for overflow. It will return TIME_T_MAX if the reutrn would be
- * smaller then either of the arguments.
- */
-extern struct timespec timespec_add_safe(const struct timespec lhs,
-					 const struct timespec rhs);
-
-
-static inline struct timespec timespec_add(struct timespec lhs,
-						struct timespec rhs)
-{
-	struct timespec ts_delta;
-	set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
-				lhs.tv_nsec + rhs.tv_nsec);
-	return ts_delta;
-}
-
-/*
- * sub = lhs - rhs, in normalized form
- */
-static inline struct timespec timespec_sub(struct timespec lhs,
-						struct timespec rhs)
-{
-	struct timespec ts_delta;
-	set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
-				lhs.tv_nsec - rhs.tv_nsec);
-	return ts_delta;
-}
-
-/*
- * Returns true if the timespec is norm, false if denorm:
- */
-static inline bool timespec_valid(const struct timespec *ts)
-{
-	/* Dates before 1970 are bogus */
-	if (ts->tv_sec < 0)
-		return false;
-	/* Can't have more nanoseconds then a second */
-	if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
-		return false;
-	return true;
-}
-
-static inline bool timespec_valid_strict(const struct timespec *ts)
-{
-	if (!timespec_valid(ts))
-		return false;
-	/* Disallow values that could overflow ktime_t */
-	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
-		return false;
-	return true;
-}
-
-static inline bool timeval_valid(const struct timeval *tv)
-{
-	/* Dates before 1970 are bogus */
-	if (tv->tv_sec < 0)
-		return false;
-
-	/* Can't have more microseconds then a second */
-	if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
-		return false;
-
-	return true;
-}
-
-extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
-
-/*
- * Validates if a timespec/timeval used to inject a time offset is valid.
- * Offsets can be postive or negative. The value of the timeval/timespec
- * is the sum of its fields, but *NOTE*: the field tv_usec/tv_nsec must
- * always be non-negative.
- */
-static inline bool timeval_inject_offset_valid(const struct timeval *tv)
-{
-	/* We don't check the tv_sec as it can be positive or negative */
-
-	/* Can't have more microseconds then a second */
-	if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
-		return false;
-	return true;
-}
-
-static inline bool timespec_inject_offset_valid(const struct timespec *ts)
-{
-	/* We don't check the tv_sec as it can be positive or negative */
-
-	/* Can't have more nanoseconds then a second */
-	if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC)
-		return false;
-	return true;
-}
-
 /* Some architectures do not supply their own clocksource.
  * This is mainly the case in architectures that get their
  * inter-tick times by reading the counter on their interval
@@ -208,73 +69,7 @@ struct tm {
 
 void time64_to_tm(time64_t totalsecs, int offset, struct tm *result);
 
-/**
- * time_to_tm - converts the calendar time to local broken-down time
- *
- * @totalsecs	the number of seconds elapsed since 00:00:00 on January 1, 1970,
- *		Coordinated Universal Time (UTC).
- * @offset	offset seconds adding to totalsecs.
- * @result	pointer to struct tm variable to receive broken-down time
- */
-static inline void time_to_tm(time_t totalsecs, int offset, struct tm *result)
-{
-	time64_to_tm(totalsecs, offset, result);
-}
-
-/**
- * timespec_to_ns - Convert timespec to nanoseconds
- * @ts:		pointer to the timespec variable to be converted
- *
- * Returns the scalar nanosecond representation of the timespec
- * parameter.
- */
-static inline s64 timespec_to_ns(const struct timespec *ts)
-{
-	return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
-}
-
-/**
- * timeval_to_ns - Convert timeval to nanoseconds
- * @ts:		pointer to the timeval variable to be converted
- *
- * Returns the scalar nanosecond representation of the timeval
- * parameter.
- */
-static inline s64 timeval_to_ns(const struct timeval *tv)
-{
-	return ((s64) tv->tv_sec * NSEC_PER_SEC) +
-		tv->tv_usec * NSEC_PER_USEC;
-}
-
-/**
- * ns_to_timespec - Convert nanoseconds to timespec
- * @nsec:	the nanoseconds value to be converted
- *
- * Returns the timespec representation of the nsec parameter.
- */
-extern struct timespec ns_to_timespec(const s64 nsec);
-
-/**
- * ns_to_timeval - Convert nanoseconds to timeval
- * @nsec:	the nanoseconds value to be converted
- *
- * Returns the timeval representation of the nsec parameter.
- */
-extern struct timeval ns_to_timeval(const s64 nsec);
-
-/**
- * timespec_add_ns - Adds nanoseconds to a timespec
- * @a:		pointer to timespec to be incremented
- * @ns:		unsigned nanoseconds value to be added
- *
- * This must always be inlined because its used from the x86-64 vdso,
- * which cannot call other kernel functions.
- */
-static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
-{
-	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
-	a->tv_nsec = ns;
-}
+# include <linux/time32.h>
 
 static inline bool itimerspec64_valid(const struct itimerspec64 *its)
 {

include/linux/time32.h

@@ -0,0 +1,221 @@
+#ifndef _LINUX_TIME32_H
+#define _LINUX_TIME32_H
+/*
+ * These are all interfaces based on the old time_t definition
+ * that overflows in 2038 on 32-bit architectures. New code
+ * should use the replacements based on time64_t and timespec64.
+ *
+ * Any interfaces in here that become unused as we migrate
+ * code to time64_t should get removed.
+ */
+
+#include <linux/time64.h>
+
+#define TIME_T_MAX	(time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
+
+#if __BITS_PER_LONG == 64
+
+/* timespec64 is defined as timespec here */
+static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
+{
+	return ts64;
+}
+
+static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
+{
+	return ts;
+}
+
+# define timespec_equal			timespec64_equal
+# define timespec_compare		timespec64_compare
+# define set_normalized_timespec	set_normalized_timespec64
+# define timespec_add			timespec64_add
+# define timespec_sub			timespec64_sub
+# define timespec_valid			timespec64_valid
+# define timespec_valid_strict		timespec64_valid_strict
+# define timespec_to_ns			timespec64_to_ns
+# define ns_to_timespec			ns_to_timespec64
+# define timespec_add_ns		timespec64_add_ns
+
+#else
+static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
+{
+	struct timespec ret;
+
+	ret.tv_sec = (time_t)ts64.tv_sec;
+	ret.tv_nsec = ts64.tv_nsec;
+	return ret;
+}
+
+static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
+{
+	struct timespec64 ret;
+
+	ret.tv_sec = ts.tv_sec;
+	ret.tv_nsec = ts.tv_nsec;
+	return ret;
+}
+
+static inline int timespec_equal(const struct timespec *a,
+				 const struct timespec *b)
+{
+	return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
+}
+
+/*
+ * lhs < rhs:  return <0
+ * lhs == rhs: return 0
+ * lhs > rhs:  return >0
+ */
+static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
+{
+	if (lhs->tv_sec < rhs->tv_sec)
+		return -1;
+	if (lhs->tv_sec > rhs->tv_sec)
+		return 1;
+	return lhs->tv_nsec - rhs->tv_nsec;
+}
+
+extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
+
+static inline struct timespec timespec_add(struct timespec lhs,
+						struct timespec rhs)
+{
+	struct timespec ts_delta;
+
+	set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
+				lhs.tv_nsec + rhs.tv_nsec);
+	return ts_delta;
+}
+
+/*
+ * sub = lhs - rhs, in normalized form
+ */
+static inline struct timespec timespec_sub(struct timespec lhs,
+						struct timespec rhs)
+{
+	struct timespec ts_delta;
+
+	set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
+				lhs.tv_nsec - rhs.tv_nsec);
+	return ts_delta;
+}
+
+/*
+ * Returns true if the timespec is norm, false if denorm:
+ */
+static inline bool timespec_valid(const struct timespec *ts)
+{
+	/* Dates before 1970 are bogus */
+	if (ts->tv_sec < 0)
+		return false;
+	/* Can't have more nanoseconds then a second */
+	if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
+		return false;
+	return true;
+}
+
+static inline bool timespec_valid_strict(const struct timespec *ts)
+{
+	if (!timespec_valid(ts))
+		return false;
+	/* Disallow values that could overflow ktime_t */
+	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
+		return false;
+	return true;
+}
+
+/**
+ * timespec_to_ns - Convert timespec to nanoseconds
+ * @ts:		pointer to the timespec variable to be converted
+ *
+ * Returns the scalar nanosecond representation of the timespec
+ * parameter.
+ */
+static inline s64 timespec_to_ns(const struct timespec *ts)
+{
+	return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
+}
+
+/**
+ * ns_to_timespec - Convert nanoseconds to timespec
+ * @nsec:	the nanoseconds value to be converted
+ *
+ * Returns the timespec representation of the nsec parameter.
+ */
+extern struct timespec ns_to_timespec(const s64 nsec);
+
+/**
+ * timespec_add_ns - Adds nanoseconds to a timespec
+ * @a:		pointer to timespec to be incremented
+ * @ns:		unsigned nanoseconds value to be added
+ *
+ * This must always be inlined because its used from the x86-64 vdso,
+ * which cannot call other kernel functions.
+ */
+static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
+{
+	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
+	a->tv_nsec = ns;
+}
+
+#endif
+
+/**
+ * time_to_tm - converts the calendar time to local broken-down time
+ *
+ * @totalsecs	the number of seconds elapsed since 00:00:00 on January 1, 1970,
+ *		Coordinated Universal Time (UTC).
+ * @offset	offset seconds adding to totalsecs.
+ * @result	pointer to struct tm variable to receive broken-down time
+ */
+static inline void time_to_tm(time_t totalsecs, int offset, struct tm *result)
+{
+	time64_to_tm(totalsecs, offset, result);
+}
+
+static inline unsigned long mktime(const unsigned int year,
+			const unsigned int mon, const unsigned int day,
+			const unsigned int hour, const unsigned int min,
+			const unsigned int sec)
+{
+	return mktime64(year, mon, day, hour, min, sec);
+}
+
+static inline bool timeval_valid(const struct timeval *tv)
+{
+	/* Dates before 1970 are bogus */
+	if (tv->tv_sec < 0)
+		return false;
+
+	/* Can't have more microseconds then a second */
+	if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
+		return false;
+
+	return true;
+}
+
+extern struct timespec timespec_trunc(struct timespec t, unsigned int gran);
+
+/**
+ * timeval_to_ns - Convert timeval to nanoseconds
+ * @ts:		pointer to the timeval variable to be converted
+ *
+ * Returns the scalar nanosecond representation of the timeval
+ * parameter.
+ */
+static inline s64 timeval_to_ns(const struct timeval *tv)
+{
+	return ((s64) tv->tv_sec * NSEC_PER_SEC) +
+		tv->tv_usec * NSEC_PER_USEC;
+}
+
+/**
+ * ns_to_timeval - Convert nanoseconds to timeval
+ * @nsec:	the nanoseconds value to be converted
+ *
+ * Returns the timeval representation of the nsec parameter.
+ */
+extern struct timeval ns_to_timeval(const s64 nsec);
+
+#endif

include/linux/time64.h

@@ -7,11 +7,8 @@
 typedef __s64 time64_t;
 typedef __u64 timeu64_t;
 
-/*
- * This wants to go into uapi/linux/time.h once we agreed about the
- * userspace interfaces.
- */
 #if __BITS_PER_LONG == 64
+/* this trick allows us to optimize out timespec64_to_timespec */
 # define timespec64 timespec
 #define itimerspec64 itimerspec
 #else
@@ -41,77 +38,6 @@ struct itimerspec64 {
 #define KTIME_MAX			((s64)~((u64)1 << 63))
 #define KTIME_SEC_MAX			(KTIME_MAX / NSEC_PER_SEC)
 
-#if __BITS_PER_LONG == 64
-
-static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
-{
-	return ts64;
-}
-
-static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
-{
-	return ts;
-}
-
-static inline struct itimerspec itimerspec64_to_itimerspec(struct itimerspec64 *its64)
-{
-	return *its64;
-}
-
-static inline struct itimerspec64 itimerspec_to_itimerspec64(struct itimerspec *its)
-{
-	return *its;
-}
-
-# define timespec64_equal		timespec_equal
-# define timespec64_compare		timespec_compare
-# define set_normalized_timespec64	set_normalized_timespec
-# define timespec64_add			timespec_add
-# define timespec64_sub			timespec_sub
-# define timespec64_valid		timespec_valid
-# define timespec64_valid_strict	timespec_valid_strict
-# define timespec64_to_ns		timespec_to_ns
-# define ns_to_timespec64		ns_to_timespec
-# define timespec64_add_ns		timespec_add_ns
-
-#else
-
-static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
-{
-	struct timespec ret;
-
-	ret.tv_sec = (time_t)ts64.tv_sec;
-	ret.tv_nsec = ts64.tv_nsec;
-	return ret;
-}
-
-static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
-{
-	struct timespec64 ret;
-
-	ret.tv_sec = ts.tv_sec;
-	ret.tv_nsec = ts.tv_nsec;
-	return ret;
-}
-
-static inline struct itimerspec itimerspec64_to_itimerspec(struct itimerspec64 *its64)
-{
-	struct itimerspec ret;
-
-	ret.it_interval = timespec64_to_timespec(its64->it_interval);
-	ret.it_value = timespec64_to_timespec(its64->it_value);
-	return ret;
-}
-
-static inline struct itimerspec64 itimerspec_to_itimerspec64(struct itimerspec *its)
-{
-	struct itimerspec64 ret;
-
-	ret.it_interval = timespec_to_timespec64(its->it_interval);
-	ret.it_value = timespec_to_timespec64(its->it_value);
-	return ret;
-}
-
 static inline int timespec64_equal(const struct timespec64 *a,
 				   const struct timespec64 *b)
 {
@@ -213,8 +139,6 @@ static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
 	a->tv_nsec = ns;
 }
 
-#endif
-
 /*
  * timespec64_add_safe assumes both values are positive and checks for
  * overflow. It will return TIME64_MAX in case of overflow.

include/linux/timekeeping.h

@@ -15,27 +15,16 @@ extern void xtime_update(unsigned long ticks);
 /*
  * Get and set timeofday
  */
-extern void do_gettimeofday(struct timeval *tv);
 extern int do_settimeofday64(const struct timespec64 *ts);
 extern int do_sys_settimeofday64(const struct timespec64 *tv,
 				 const struct timezone *tz);
 /*
  * Kernel time accessors
  */
-unsigned long get_seconds(void);
 struct timespec64 current_kernel_time64(void);
-/* does not take xtime_lock */
-struct timespec __current_kernel_time(void);
-
-static inline struct timespec current_kernel_time(void)
-{
-	struct timespec64 now = current_kernel_time64();
-
-	return timespec64_to_timespec(now);
-}
 
 /*
- * timespec based interfaces
+ * timespec64 based interfaces
  */
 struct timespec64 get_monotonic_coarse64(void);
 extern void getrawmonotonic64(struct timespec64 *ts);
@@ -47,116 +36,6 @@ extern int __getnstimeofday64(struct timespec64 *tv);
 extern void getnstimeofday64(struct timespec64 *tv);
 extern void getboottime64(struct timespec64 *ts);
 
-#if BITS_PER_LONG == 64
-/**
- * Deprecated. Use do_settimeofday64().
- */
-static inline int do_settimeofday(const struct timespec *ts)
-{
-	return do_settimeofday64(ts);
-}
-
-static inline int __getnstimeofday(struct timespec *ts)
-{
-	return __getnstimeofday64(ts);
-}
-
-static inline void getnstimeofday(struct timespec *ts)
-{
-	getnstimeofday64(ts);
-}
-
-static inline void ktime_get_ts(struct timespec *ts)
-{
-	ktime_get_ts64(ts);
-}
-
-static inline void ktime_get_real_ts(struct timespec *ts)
-{
-	getnstimeofday64(ts);
-}
-
-static inline void getrawmonotonic(struct timespec *ts)
-{
-	getrawmonotonic64(ts);
-}
-
-static inline struct timespec get_monotonic_coarse(void)
-{
-	return get_monotonic_coarse64();
-}
-
-static inline void getboottime(struct timespec *ts)
-{
-	return getboottime64(ts);
-}
-#else
-/**
- * Deprecated. Use do_settimeofday64().
- */
-static inline int do_settimeofday(const struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	ts64 = timespec_to_timespec64(*ts);
-	return do_settimeofday64(&ts64);
-}
-
-static inline int __getnstimeofday(struct timespec *ts)
-{
-	struct timespec64 ts64;
-	int ret = __getnstimeofday64(&ts64);
-
-	*ts = timespec64_to_timespec(ts64);
-	return ret;
-}
-
-static inline void getnstimeofday(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	getnstimeofday64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline void ktime_get_ts(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	ktime_get_ts64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline void ktime_get_real_ts(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	getnstimeofday64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline void getrawmonotonic(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	getrawmonotonic64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline struct timespec get_monotonic_coarse(void)
-{
-	return timespec64_to_timespec(get_monotonic_coarse64());
-}
-
-static inline void getboottime(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	getboottime64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-#endif
-
 #define ktime_get_real_ts64(ts)	getnstimeofday64(ts)
 
 /*
@@ -242,23 +121,13 @@ extern u64 ktime_get_boot_fast_ns(void);
 extern u64 ktime_get_real_fast_ns(void);
 
 /*
- * Timespec interfaces utilizing the ktime based ones
+ * timespec64 interfaces utilizing the ktime based ones
  */
-static inline void get_monotonic_boottime(struct timespec *ts)
-{
-	*ts = ktime_to_timespec(ktime_get_boottime());
-}
-
 static inline void get_monotonic_boottime64(struct timespec64 *ts)
 {
 	*ts = ktime_to_timespec64(ktime_get_boottime());
 }
 
-static inline void timekeeping_clocktai(struct timespec *ts)
-{
-	*ts = ktime_to_timespec(ktime_get_clocktai());
-}
-
 static inline void timekeeping_clocktai64(struct timespec64 *ts)
 {
 	*ts = ktime_to_timespec64(ktime_get_clocktai());
@@ -341,10 +210,8 @@ extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
  */
 extern int persistent_clock_is_local;
 
-extern void read_persistent_clock(struct timespec *ts);
 extern void read_persistent_clock64(struct timespec64 *ts);
 extern void read_boot_clock64(struct timespec64 *ts);
-extern int update_persistent_clock(struct timespec now);
 extern int update_persistent_clock64(struct timespec64 now);
 
 

include/linux/timekeeping32.h

@@ -0,0 +1,151 @@
+#ifndef _LINUX_TIMEKEEPING32_H
+#define _LINUX_TIMEKEEPING32_H
+/*
+ * These interfaces are all based on the old timespec type
+ * and should get replaced with the timespec64 based versions
+ * over time so we can remove the file here.
+ */
+
+extern void do_gettimeofday(struct timeval *tv);
+unsigned long get_seconds(void);
+
+/* does not take xtime_lock */
+struct timespec __current_kernel_time(void);
+
+static inline struct timespec current_kernel_time(void)
+{
+	struct timespec64 now = current_kernel_time64();
+
+	return timespec64_to_timespec(now);
+}
+
+#if BITS_PER_LONG == 64
+/**
+ * Deprecated. Use do_settimeofday64().
+ */
+static inline int do_settimeofday(const struct timespec *ts)
+{
+	return do_settimeofday64(ts);
+}
+
+static inline int __getnstimeofday(struct timespec *ts)
+{
+	return __getnstimeofday64(ts);
+}
+
+static inline void getnstimeofday(struct timespec *ts)
+{
+	getnstimeofday64(ts);
+}
+
+static inline void ktime_get_ts(struct timespec *ts)
+{
+	ktime_get_ts64(ts);
+}
+
+static inline void ktime_get_real_ts(struct timespec *ts)
+{
+	getnstimeofday64(ts);
+}
+
+static inline void getrawmonotonic(struct timespec *ts)
+{
+	getrawmonotonic64(ts);
+}
+
+static inline struct timespec get_monotonic_coarse(void)
+{
+	return get_monotonic_coarse64();
+}
+
+static inline void getboottime(struct timespec *ts)
+{
+	return getboottime64(ts);
+}
+#else
+/**
+ * Deprecated. Use do_settimeofday64().
+ */
+static inline int do_settimeofday(const struct timespec *ts)
+{
+	struct timespec64 ts64;
+
+	ts64 = timespec_to_timespec64(*ts);
+	return do_settimeofday64(&ts64);
+}
+
+static inline int __getnstimeofday(struct timespec *ts)
+{
+	struct timespec64 ts64;
+	int ret = __getnstimeofday64(&ts64);
+
+	*ts = timespec64_to_timespec(ts64);
+	return ret;
+}
+
+static inline void getnstimeofday(struct timespec *ts)
+{
+	struct timespec64 ts64;
+
+	getnstimeofday64(&ts64);
+	*ts = timespec64_to_timespec(ts64);
+}
+
+static inline void ktime_get_ts(struct timespec *ts)
+{
+	struct timespec64 ts64;
+
+	ktime_get_ts64(&ts64);
+	*ts = timespec64_to_timespec(ts64);
+}
+
+static inline void ktime_get_real_ts(struct timespec *ts)
+{
+	struct timespec64 ts64;
+
+	getnstimeofday64(&ts64);
+	*ts = timespec64_to_timespec(ts64);
+}
+
+static inline void getrawmonotonic(struct timespec *ts)
+{
+	struct timespec64 ts64;
+
+	getrawmonotonic64(&ts64);
+	*ts = timespec64_to_timespec(ts64);
+}
+
+static inline struct timespec get_monotonic_coarse(void)
+{
+	return timespec64_to_timespec(get_monotonic_coarse64());
+}
+
+static inline void getboottime(struct timespec *ts)
+{
+	struct timespec64 ts64;
+
+	getboottime64(&ts64);
+	*ts = timespec64_to_timespec(ts64);
+}
+#endif
+
+/*
+ * Timespec interfaces utilizing the ktime based ones
+ */
+static inline void get_monotonic_boottime(struct timespec *ts)
+{
+	*ts = ktime_to_timespec(ktime_get_boottime());
+}
+
+static inline void timekeeping_clocktai(struct timespec *ts)
+{
+	*ts = ktime_to_timespec(ktime_get_clocktai());
+}
+
+/*
+ * Persistent clock related interfaces
+ */
+extern void read_persistent_clock(struct timespec *ts);
+extern int update_persistent_clock(struct timespec now);
+
+#endif

kernel/time/ntp.c

@@ -492,6 +492,67 @@ out:
 	return leap;
 }
 
+static void sync_hw_clock(struct work_struct *work);
+static DECLARE_DELAYED_WORK(sync_work, sync_hw_clock);
+
+static void sched_sync_hw_clock(struct timespec64 now,
+				unsigned long target_nsec, bool fail)
+
+{
+	struct timespec64 next;
+
+	getnstimeofday64(&next);
+	if (!fail)
+		next.tv_sec = 659;
+	else {
+		/*
+		 * Try again as soon as possible. Delaying long periods
+		 * decreases the accuracy of the work queue timer. Due to this
+		 * the algorithm is very likely to require a short-sleep retry
+		 * after the above long sleep to synchronize ts_nsec.
+		 */
+		next.tv_sec = 0;
+	}
+
+	/* Compute the needed delay that will get to tv_nsec == target_nsec */
+	next.tv_nsec = target_nsec - next.tv_nsec;
+	if (next.tv_nsec <= 0)
+		next.tv_nsec += NSEC_PER_SEC;
+	if (next.tv_nsec >= NSEC_PER_SEC) {
+		next.tv_sec++;
+		next.tv_nsec -= NSEC_PER_SEC;
+	}
+
+	queue_delayed_work(system_power_efficient_wq, &sync_work,
+			   timespec64_to_jiffies(&next));
+}
+
+static void sync_rtc_clock(void)
+{
+	unsigned long target_nsec;
+	struct timespec64 adjust, now;
+	int rc;
+
+	if (!IS_ENABLED(CONFIG_RTC_SYSTOHC))
+		return;
+
+	getnstimeofday64(&now);
+
+	adjust = now;
+	if (persistent_clock_is_local)
+		adjust.tv_sec -= (sys_tz.tz_minuteswest * 60);
+
+	/*
+	 * The current RTC in use will provide the target_nsec it wants to be
+	 * called at, and does rtc_tv_nsec_ok internally.
+	 */
+	rc = rtc_set_ntp_time(adjust, &target_nsec);
+	if (rc == -ENODEV)
+		return;
+
+	sched_sync_hw_clock(now, target_nsec, rc);
+}
+
 #ifdef CONFIG_GENERIC_CMOS_UPDATE
 int __weak update_persistent_clock(struct timespec now)
 {
@@ -507,76 +568,75 @@ int __weak update_persistent_clock64(struct timespec64 now64)
 }
 #endif
 
-#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC)
-static void sync_cmos_clock(struct work_struct *work);
-
-static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock);
-
-static void sync_cmos_clock(struct work_struct *work)
+static bool sync_cmos_clock(void)
 {
+	static bool no_cmos;
 	struct timespec64 now;
-	struct timespec64 next;
-	int fail = 1;
+	struct timespec64 adjust;
+	int rc = -EPROTO;
+	long target_nsec = NSEC_PER_SEC / 2;
+
+	if (!IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE))
+		return false;
+
+	if (no_cmos)
+		return false;
 
 	/*
-	 * If we have an externally synchronized Linux clock, then update
-	 * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
-	 * called as close as possible to 500 ms before the new second starts.
-	 * This code is run on a timer.  If the clock is set, that timer
-	 * may not expire at the correct time.  Thus, we adjust...
-	 * We want the clock to be within a couple of ticks from the target.
+	 * Historically update_persistent_clock64() has followed x86
+	 * semantics, which match the MC146818A/etc RTC. This RTC will store
+	 * 'adjust' and then in .5s it will advance once second.
+	 *
+	 * Architectures are strongly encouraged to use rtclib and not
+	 * implement this legacy API.
 	 */
-	if (!ntp_synced()) {
-		/*
-		 * Not synced, exit, do not restart a timer (if one is
-		 * running, let it run out).
-		 */
-		return;
-	}
-
 	getnstimeofday64(&now);
-	if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec * 5) {
-		struct timespec64 adjust = now;
-
-		fail = -ENODEV;
+	if (rtc_tv_nsec_ok(-1 * target_nsec, &adjust, &now)) {
 		if (persistent_clock_is_local)
 			adjust.tv_sec -= (sys_tz.tz_minuteswest * 60);
-#ifdef CONFIG_GENERIC_CMOS_UPDATE
-		fail = update_persistent_clock64(adjust);
-#endif
-
-#ifdef CONFIG_RTC_SYSTOHC
-		if (fail == -ENODEV)
-			fail = rtc_set_ntp_time(adjust);
-#endif
+		rc = update_persistent_clock64(adjust);
+		/*
+		 * The machine does not support update_persistent_clock64 even
+		 * though it defines CONFIG_GENERIC_CMOS_UPDATE.
+		 */
+		if (rc == -ENODEV) {
+			no_cmos = true;
+			return false;
+		}
 	}
 
-	next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec - (TICK_NSEC / 2);
-	if (next.tv_nsec <= 0)
-		next.tv_nsec += NSEC_PER_SEC;
+	sched_sync_hw_clock(now, target_nsec, rc);
+	return true;
+}
 
-	if (!fail || fail == -ENODEV)
-		next.tv_sec = 659;
-	else
-		next.tv_sec = 0;
+/*
+ * If we have an externally synchronized Linux clock, then update RTC clock
+ * accordingly every ~11 minutes. Generally RTCs can only store second
+ * precision, but many RTCs will adjust the phase of their second tick to
+ * match the moment of update. This infrastructure arranges to call to the RTC
+ * set at the correct moment to phase synchronize the RTC second tick over
+ * with the kernel clock.
+ */
+static void sync_hw_clock(struct work_struct *work)
+{
+	if (!ntp_synced())
+		return;
 
-	if (next.tv_nsec >= NSEC_PER_SEC) {
-		next.tv_sec++;
-		next.tv_nsec -= NSEC_PER_SEC;
-	}
-	queue_delayed_work(system_power_efficient_wq,
-			   &sync_cmos_work, timespec64_to_jiffies(&next));
+	if (sync_cmos_clock())
+		return;
+
+	sync_rtc_clock();
 }
 
 void ntp_notify_cmos_timer(void)
 {
-	queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0);
-}
-
-#else
-void ntp_notify_cmos_timer(void) { }
-#endif
+	if (!ntp_synced())
+		return;
 
+	if (IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE) ||
+	    IS_ENABLED(CONFIG_RTC_SYSTOHC))
+		queue_delayed_work(system_power_efficient_wq, &sync_work, 0);
+}
 
 /*
  * Propagate a new txc->status value into the NTP state:
@@ -653,67 +713,6 @@ static inline void process_adjtimex_modes(struct timex *txc,
 }
 
 
-
-/**
- * ntp_validate_timex - Ensures the timex is ok for use in do_adjtimex
- */
-int ntp_validate_timex(struct timex *txc)
-{
-	if (txc->modes & ADJ_ADJTIME) {
-		/* singleshot must not be used with any other mode bits */
-		if (!(txc->modes & ADJ_OFFSET_SINGLESHOT))
-			return -EINVAL;
-		if (!(txc->modes & ADJ_OFFSET_READONLY) &&
-		    !capable(CAP_SYS_TIME))
-			return -EPERM;
-	} else {
-		/* In order to modify anything, you gotta be super-user! */
-		 if (txc->modes && !capable(CAP_SYS_TIME))
-			return -EPERM;
-		/*
-		 * if the quartz is off by more than 10% then
-		 * something is VERY wrong!
-		 */
-		if (txc->modes & ADJ_TICK &&
-		    (txc->tick <  900000/USER_HZ ||
-		     txc->tick > 1100000/USER_HZ))
-			return -EINVAL;
-	}
-
-	if (txc->modes & ADJ_SETOFFSET) {
-		/* In order to inject time, you gotta be super-user! */
-		if (!capable(CAP_SYS_TIME))
-			return -EPERM;
-
-		if (txc->modes & ADJ_NANO) {
-			struct timespec ts;
-
-			ts.tv_sec = txc->time.tv_sec;
-			ts.tv_nsec = txc->time.tv_usec;
-			if (!timespec_inject_offset_valid(&ts))
-				return -EINVAL;
-
-		} else {
-			if (!timeval_inject_offset_valid(&txc->time))
-				return -EINVAL;
-		}
-	}
-
-	/*
-	 * Check for potential multiplication overflows that can
-	 * only happen on 64-bit systems:
-	 */
-	if ((txc->modes & ADJ_FREQUENCY) && (BITS_PER_LONG == 64)) {
-		if (LLONG_MIN / PPM_SCALE > txc->freq)
-			return -EINVAL;
-		if (LLONG_MAX / PPM_SCALE < txc->freq)
-			return -EINVAL;
-	}
-
-	return 0;
-}
-
-
 /*
  * adjtimex mainly allows reading (and writing, if superuser) of
  * kernel time-keeping variables. used by xntpd.

kernel/time/ntp_internal.h

@@ -7,7 +7,6 @@ extern void ntp_clear(void);
 extern u64 ntp_tick_length(void);
 extern ktime_t ntp_get_next_leap(void);
 extern int second_overflow(time64_t secs);
-extern int ntp_validate_timex(struct timex *);
 extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *);
 extern void __hardpps(const struct timespec64 *, const struct timespec64 *);
 #endif /* _LINUX_NTP_INTERNAL_H */

kernel/time/time.c

@@ -157,40 +157,6 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv,
 	return 0;
 }
 
-/*
- * Indicates if there is an offset between the system clock and the hardware
- * clock/persistent clock/rtc.
- */
-int persistent_clock_is_local;
-
-/*
- * Adjust the time obtained from the CMOS to be UTC time instead of
- * local time.
- *
- * This is ugly, but preferable to the alternatives.  Otherwise we
- * would either need to write a program to do it in /etc/rc (and risk
- * confusion if the program gets run more than once; it would also be
- * hard to make the program warp the clock precisely n hours)  or
- * compile in the timezone information into the kernel.  Bad, bad....
- *
- *						- TYT, 1992-01-01
- *
- * The best thing to do is to keep the CMOS clock in universal time (UTC)
- * as real UNIX machines always do it. This avoids all headaches about
- * daylight saving times and warping kernel clocks.
- */
-static inline void warp_clock(void)
-{
-	if (sys_tz.tz_minuteswest != 0) {
-		struct timespec adjust;
-
-		persistent_clock_is_local = 1;
-		adjust.tv_sec = sys_tz.tz_minuteswest * 60;
-		adjust.tv_nsec = 0;
-		timekeeping_inject_offset(&adjust);
-	}
-}
-
 /*
  * In case for some reason the CMOS clock has not already been running
  * in UTC, but in some local time: The first time we set the timezone,
@@ -224,7 +190,7 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz
 		if (firsttime) {
 			firsttime = 0;
 			if (!tv)
-				warp_clock();
+				timekeeping_warp_clock();
 		}
 	}
 	if (tv)
@@ -441,6 +407,7 @@ time64_t mktime64(const unsigned int year0, const unsigned int mon0,
 }
 EXPORT_SYMBOL(mktime64);
 
+#if __BITS_PER_LONG == 32
 /**
  * set_normalized_timespec - set timespec sec and nsec parts and normalize
  *
@@ -501,6 +468,7 @@ struct timespec ns_to_timespec(const s64 nsec)
 	return ts;
 }
 EXPORT_SYMBOL(ns_to_timespec);
+#endif
 
 /**
  * ns_to_timeval - Convert nanoseconds to timeval
@@ -520,7 +488,6 @@ struct timeval ns_to_timeval(const s64 nsec)
 }
 EXPORT_SYMBOL(ns_to_timeval);
 
-#if BITS_PER_LONG == 32
 /**
  * set_normalized_timespec - set timespec sec and nsec parts and normalize
  *
@@ -581,7 +548,7 @@ struct timespec64 ns_to_timespec64(const s64 nsec)
 	return ts;
 }
 EXPORT_SYMBOL(ns_to_timespec64);
-#endif
+
 /**
  * msecs_to_jiffies: - convert milliseconds to jiffies
  * @m:	time in milliseconds
@@ -852,24 +819,6 @@ unsigned long nsecs_to_jiffies(u64 n)
 }
 EXPORT_SYMBOL_GPL(nsecs_to_jiffies);
 
-/*
- * Add two timespec values and do a safety check for overflow.
- * It's assumed that both values are valid (>= 0)
- */
-struct timespec timespec_add_safe(const struct timespec lhs,
-				  const struct timespec rhs)
-{
-	struct timespec res;
-
-	set_normalized_timespec(&res, lhs.tv_sec + rhs.tv_sec,
-				lhs.tv_nsec + rhs.tv_nsec);
-
-	if (res.tv_sec < lhs.tv_sec || res.tv_sec < rhs.tv_sec)
-		res.tv_sec = TIME_T_MAX;
-
-	return res;
-}
-
 /*
  * Add two timespec64 values and do a safety check for overflow.
  * It's assumed that both values are valid (>= 0).

kernel/time/timekeeping.c

@@ -1306,33 +1306,31 @@ EXPORT_SYMBOL(do_settimeofday64);
  *
  * Adds or subtracts an offset value from the current time.
  */
-int timekeeping_inject_offset(struct timespec *ts)
+static int timekeeping_inject_offset(struct timespec64 *ts)
 {
 	struct timekeeper *tk = &tk_core.timekeeper;
 	unsigned long flags;
-	struct timespec64 ts64, tmp;
+	struct timespec64 tmp;
 	int ret = 0;
 
-	if (!timespec_inject_offset_valid(ts))
+	if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC)
 		return -EINVAL;
 
-	ts64 = timespec_to_timespec64(*ts);
-
 	raw_spin_lock_irqsave(&timekeeper_lock, flags);
 	write_seqcount_begin(&tk_core.seq);
 
 	timekeeping_forward_now(tk);
 
 	/* Make sure the proposed value is valid */
-	tmp = timespec64_add(tk_xtime(tk),  ts64);
-	if (timespec64_compare(&tk->wall_to_monotonic, &ts64) > 0 ||
+	tmp = timespec64_add(tk_xtime(tk), *ts);
+	if (timespec64_compare(&tk->wall_to_monotonic, ts) > 0 ||
 	    !timespec64_valid_strict(&tmp)) {
 		ret = -EINVAL;
 		goto error;
 	}
 
-	tk_xtime_add(tk, &ts64);
-	tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts64));
+	tk_xtime_add(tk, ts);
+	tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, *ts));
 
 error: /* even if we error out, we forwarded the time, so call update */
 	timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
@@ -1345,7 +1343,40 @@ error: /* even if we error out, we forwarded the time, so call update */
 
 	return ret;
 }
-EXPORT_SYMBOL(timekeeping_inject_offset);
+
+/*
+ * Indicates if there is an offset between the system clock and the hardware
+ * clock/persistent clock/rtc.
+ */
+int persistent_clock_is_local;
+
+/*
+ * Adjust the time obtained from the CMOS to be UTC time instead of
+ * local time.
+ *
+ * This is ugly, but preferable to the alternatives.  Otherwise we
+ * would either need to write a program to do it in /etc/rc (and risk
+ * confusion if the program gets run more than once; it would also be
+ * hard to make the program warp the clock precisely n hours)  or
+ * compile in the timezone information into the kernel.  Bad, bad....
+ *
+ *						- TYT, 1992-01-01
+ *
+ * The best thing to do is to keep the CMOS clock in universal time (UTC)
+ * as real UNIX machines always do it. This avoids all headaches about
+ * daylight saving times and warping kernel clocks.
+ */
+void timekeeping_warp_clock(void)
+{
+	if (sys_tz.tz_minuteswest != 0) {
+		struct timespec64 adjust;
+
+		persistent_clock_is_local = 1;
+		adjust.tv_sec = sys_tz.tz_minuteswest * 60;
+		adjust.tv_nsec = 0;
+		timekeeping_inject_offset(&adjust);
+	}
+}
 
 /**
  * __timekeeping_set_tai_offset - Sets the TAI offset from UTC and monotonic
@@ -2289,6 +2320,72 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real,
 	return base;
 }
 
+/**
+ * timekeeping_validate_timex - Ensures the timex is ok for use in do_adjtimex
+ */
+static int timekeeping_validate_timex(struct timex *txc)
+{
+	if (txc->modes & ADJ_ADJTIME) {
+		/* singleshot must not be used with any other mode bits */
+		if (!(txc->modes & ADJ_OFFSET_SINGLESHOT))
+			return -EINVAL;
+		if (!(txc->modes & ADJ_OFFSET_READONLY) &&
+		    !capable(CAP_SYS_TIME))
+			return -EPERM;
+	} else {
+		/* In order to modify anything, you gotta be super-user! */
+		if (txc->modes && !capable(CAP_SYS_TIME))
+			return -EPERM;
+		/*
+		 * if the quartz is off by more than 10% then
+		 * something is VERY wrong!
+		 */
+		if (txc->modes & ADJ_TICK &&
+		    (txc->tick <  900000/USER_HZ ||
+		     txc->tick > 1100000/USER_HZ))
+			return -EINVAL;
+	}
+
+	if (txc->modes & ADJ_SETOFFSET) {
+		/* In order to inject time, you gotta be super-user! */
+		if (!capable(CAP_SYS_TIME))
+			return -EPERM;
+
+		/*
+		 * Validate if a timespec/timeval used to inject a time
+		 * offset is valid.  Offsets can be postive or negative, so
+		 * we don't check tv_sec. The value of the timeval/timespec
+		 * is the sum of its fields,but *NOTE*:
+		 * The field tv_usec/tv_nsec must always be non-negative and
+		 * we can't have more nanoseconds/microseconds than a second.
+		 */
+		if (txc->time.tv_usec < 0)
+			return -EINVAL;
+
+		if (txc->modes & ADJ_NANO) {
+			if (txc->time.tv_usec >= NSEC_PER_SEC)
+				return -EINVAL;
+		} else {
+			if (txc->time.tv_usec >= USEC_PER_SEC)
+				return -EINVAL;
+		}
+	}
+
+	/*
+	 * Check for potential multiplication overflows that can
+	 * only happen on 64-bit systems:
+	 */
+	if ((txc->modes & ADJ_FREQUENCY) && (BITS_PER_LONG == 64)) {
+		if (LLONG_MIN / PPM_SCALE > txc->freq)
+			return -EINVAL;
+		if (LLONG_MAX / PPM_SCALE < txc->freq)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+
 /**
  * do_adjtimex() - Accessor function to NTP __do_adjtimex function
  */
@@ -2301,12 +2398,12 @@ int do_adjtimex(struct timex *txc)
 	int ret;
 
 	/* Validate the data before disabling interrupts */
-	ret = ntp_validate_timex(txc);
+	ret = timekeeping_validate_timex(txc);
 	if (ret)
 		return ret;
 
 	if (txc->modes & ADJ_SETOFFSET) {
-		struct timespec delta;
+		struct timespec64 delta;
 		delta.tv_sec  = txc->time.tv_sec;
 		delta.tv_nsec = txc->time.tv_usec;
 		if (!(txc->modes & ADJ_NANO))

kernel/time/timekeeping.h

@@ -10,7 +10,7 @@ extern ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq,
 
 extern int timekeeping_valid_for_hres(void);
 extern u64 timekeeping_max_deferment(void);
-extern int timekeeping_inject_offset(struct timespec *ts);
+extern void timekeeping_warp_clock(void);
 extern int timekeeping_suspend(void);
 extern void timekeeping_resume(void);