time: Provide y2038 safe timekeeping_inject_sleeptime() replacement

As part of addressing "y2038 problem" for in-kernel uses, this
patch adds timekeeping_inject_sleeptime64() using timespec64.

After this patch, timekeeping_inject_sleeptime() is deprecated
and all its call sites will be fixed using the new interface,
after that it can be removed.

NOTE: timekeeping_inject_sleeptime() is safe actually, but we
want to eliminate timespec eventually, so comes this patch.
Signed-off-by: Npang.xunlei <pang.xunlei@linaro.org>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>

include/linux/timekeeping.h

@@ -201,7 +201,18 @@ static inline void timekeeping_clocktai(struct timespec *ts)
 /*
  * RTC specific
  */
-extern void timekeeping_inject_sleeptime(struct timespec *delta);
+extern void timekeeping_inject_sleeptime64(struct timespec64 *delta);
+
+/**
+ * Deprecated. Use timekeeping_inject_sleeptime64().
+ */
+static inline void timekeeping_inject_sleeptime(struct timespec *delta)
+{
+	struct timespec64 delta64;
+
+	delta64 = timespec_to_timespec64(*delta);
+	timekeeping_inject_sleeptime64(&delta64);
+}
 
 /*
  * PPS accessor

kernel/time/timekeeping.c

@@ -1067,8 +1067,8 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
 }
 
 /**
- * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values
- * @delta: pointer to a timespec delta value
+ * 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
  * because their RTC/persistent clock is only accessible when irqs are enabled.
@@ -1076,10 +1076,9 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
  * This function should only be called by rtc_resume(), and allows
  * a suspend offset to be injected into the timekeeping values.
  */
-void timekeeping_inject_sleeptime(struct timespec *delta)
+void timekeeping_inject_sleeptime64(struct timespec64 *delta)
 {
 	struct timekeeper *tk = &tk_core.timekeeper;
-	struct timespec64 tmp;
 	unsigned long flags;
 
 	/*
@@ -1094,8 +1093,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
 
 	timekeeping_forward_now(tk);
 
-	tmp = timespec_to_timespec64(*delta);
-	__timekeeping_inject_sleeptime(tk, &tmp);
+	__timekeeping_inject_sleeptime(tk, delta);
 
 	timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);