1 files changed, 108 insertions, 0 deletions

diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h
new file mode 100644
index 000000000000..e1d558e237ec
--- /dev/null
+++ b/include/linux/timekeeper_internal.h
@@ -0,0 +1,108 @@
+/*
+ * 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;
+        /* 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;
+        /* Seqlock for all timekeeper values */
+        seqlock_t               lock;
+};
+
+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 */