/*
   * You SHOULD NOT be including this unless you're vsyscall
   * handling code or timekeeping internal code!
   */
  
  #ifndef _LINUX_TIMEKEEPER_INTERNAL_H
  #define _LINUX_TIMEKEEPER_INTERNAL_H
  
  #include <linux/clocksource.h>
  #include <linux/jiffies.h>
  #include <linux/time.h>
  
  /* Structure holding internal timekeeping values. */
  struct timekeeper {
  	/* Current clocksource used for timekeeping. */
  	struct clocksource	*clock;
  	/* NTP adjusted clock multiplier */
  	u32			mult;
  	/* The shift value of the current clocksource. */
  	u32			shift;
  	/* Number of clock cycles in one NTP interval. */
  	cycle_t			cycle_interval;
  	/* Last cycle value (also stored in clock->cycle_last) */
  	cycle_t			cycle_last;
  	/* Number of clock shifted nano seconds in one NTP interval. */
  	u64			xtime_interval;
  	/* shifted nano seconds left over when rounding cycle_interval */
  	s64			xtime_remainder;
  	/* Raw nano seconds accumulated per NTP interval. */
  	u32			raw_interval;
  
  	/* Current CLOCK_REALTIME time in seconds */
  	u64			xtime_sec;
  	/* Clock shifted nano seconds */
  	u64			xtime_nsec;
  
  	/* Difference between accumulated time and NTP time in ntp
  	 * shifted nano seconds. */
  	s64			ntp_error;
  	/* Shift conversion between clock shifted nano seconds and
  	 * ntp shifted nano seconds. */
  	u32			ntp_error_shift;
  
  	/*
  	 * wall_to_monotonic is what we need to add to xtime (or xtime corrected
  	 * for sub jiffie times) to get to monotonic time.  Monotonic is pegged
  	 * at zero at system boot time, so wall_to_monotonic will be negative,
  	 * however, we will ALWAYS keep the tv_nsec part positive so we can use
  	 * the usual normalization.
  	 *
  	 * wall_to_monotonic is moved after resume from suspend for the
  	 * monotonic time not to jump. We need to add total_sleep_time to
  	 * wall_to_monotonic to get the real boot based time offset.
  	 *
  	 * - wall_to_monotonic is no longer the boot time, getboottime must be
  	 * used instead.
  	 */
  	struct timespec		wall_to_monotonic;
  	/* Offset clock monotonic -> clock realtime */
  	ktime_t			offs_real;
  	/* time spent in suspend */
  	struct timespec		total_sleep_time;
  	/* Offset clock monotonic -> clock boottime */
  	ktime_t			offs_boot;
  	/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
  	struct timespec		raw_time;
  	/* The current UTC to TAI offset in seconds */
  	s32			tai_offset;
  	/* Offset clock monotonic -> clock tai */
  	ktime_t			offs_tai;
  
  };
  
  static inline struct timespec tk_xtime(struct timekeeper *tk)
  {
  	struct timespec ts;
  
  	ts.tv_sec = tk->xtime_sec;
  	ts.tv_nsec = (long)(tk->xtime_nsec >> tk->shift);
  	return ts;
  }
  
  
  #ifdef CONFIG_GENERIC_TIME_VSYSCALL
  
  extern void update_vsyscall(struct timekeeper *tk);
  extern void update_vsyscall_tz(void);
  
  #elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD)
  
  extern void update_vsyscall_old(struct timespec *ts, struct timespec *wtm,
  				struct clocksource *c, u32 mult);
  extern void update_vsyscall_tz(void);
  
  static inline void update_vsyscall(struct timekeeper *tk)
  {
  	struct timespec xt;
  
  	xt = tk_xtime(tk);
  	update_vsyscall_old(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);
  }
  
  #else
  
  static inline void update_vsyscall(struct timekeeper *tk)
  {
  }
  static inline void update_vsyscall_tz(void)
  {
  }
  #endif
  
  #endif /* _LINUX_TIMEKEEPER_INTERNAL_H */