@@ -282,26 +282,52 @@ static struct {
spinlock_t lock;
} host_ts;
-static struct timespec64 hv_get_adj_host_time(void)
+static inline u64 reftime_to_ns(u64 reftime)
{
- struct timespec64 ts;
- u64 newtime, reftime;
+ return (reftime - WLTIMEDELTA) * 100;
+}
+
+/*
+ * Hard coded threshold for host timesync delay: 600 seconds
+ */
+static const u64 HOST_TIMESYNC_DELAY_THRESH = 600 * (u64)NSEC_PER_SEC;
+
+static int hv_get_adj_host_time(struct timespec64 *ts)
+{
+ u64 newtime, reftime, timediff_adj;
unsigned long flags;
+ int ret = 0;
spin_lock_irqsave(&host_ts.lock, flags);
reftime = hv_read_reference_counter();
- newtime = host_ts.host_time + (reftime - host_ts.ref_time);
- ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
+
+ /*
+ * We need to let the caller know that last update from host
+ * is older than the max allowable threshold. clock_gettime()
+ * and PTP ioctl do not have a documented error that we could
+ * return for this specific case. Use ESTALE to report this.
+ */
+ timediff_adj = reftime - host_ts.ref_time;
+ if (timediff_adj * 100 > HOST_TIMESYNC_DELAY_THRESH) {
+ pr_warn_once("TIMESYNC IC: Stale time stamp, %llu nsecs old\n",
+ (timediff_adj * 100));
+ ret = -ESTALE;
+ }
+
+ newtime = host_ts.host_time + timediff_adj;
+ *ts = ns_to_timespec64(reftime_to_ns(newtime));
spin_unlock_irqrestore(&host_ts.lock, flags);
- return ts;
+ return ret;
}
static void hv_set_host_time(struct work_struct *work)
{
- struct timespec64 ts = hv_get_adj_host_time();
- do_settimeofday64(&ts);
+ struct timespec64 ts;
+
+ if (!hv_get_adj_host_time(&ts))
+ do_settimeofday64(&ts);
}
/*
@@ -622,9 +648,7 @@ static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
{
- *ts = hv_get_adj_host_time();
-
- return 0;
+ return hv_get_adj_host_time(ts);
}
static struct ptp_clock_info ptp_hyperv_info = {