[PATCH 1/5] ntp/pps: use timespec64 for hardpps()

Arnd Bergmann
2015-09-28T20:24:14Z

There is only one user of the hardpps function in the kernel, so
it makes sense to atomically change it over to using 64-bit
timestamps for y2038 safety. In the hardpps implementation,
we also need to change the pps_normtime structure, which is
similar to struct timespec and also requires a 64-bit
seconds portion.

This introduces two temporary variables in pps_kc_event() to
do the conversion, they will be removed again in the next step,
which seemed preferable to having a larger patch changing it
all at the same time.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/pps/kc.c | 4 +++-
include/linux/timex.h | 2 +-
kernel/time/ntp.c | 12 ++++++------
kernel/time/ntp_internal.h | 2 +-
kernel/time/timekeeping.c | 2 +-
5 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/pps/kc.c b/drivers/pps/kc.c
index e219db1f1c84..a16cea2ba980 100644
--- a/drivers/pps/kc.c
+++ b/drivers/pps/kc.c
@@ -113,10 +113,12 @@ void pps_kc_event(struct pps_device *pps, struct pps_event_time *ts,
int event)
{
unsigned long flags;
+ struct timespec64 real = timespec_to_timespec64(ts->ts_real);
+ struct timespec64 raw = timespec_to_timespec64(ts->ts_raw);

/* Pass some events to kernel consumer if activated */
spin_lock_irqsave(&pps_kc_hardpps_lock, flags);
if (pps == pps_kc_hardpps_dev && event & pps_kc_hardpps_mode)
- hardpps(&ts->ts_real, &ts->ts_raw);
+ hardpps(&real, &raw);
spin_unlock_irqrestore(&pps_kc_hardpps_lock, flags);
}
diff --git a/include/linux/timex.h b/include/linux/timex.h
index 9d3f1a5b6178..39c25dbebfe8 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -152,7 +152,7 @@ extern unsigned long tick_nsec; /* SHIFTED_HZ period (nsec) */
#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)

extern int do_adjtimex(struct timex *);
-extern void hardpps(const struct timespec *, const struct timespec *);
+extern void hardpps(const struct timespec64 *, const struct timespec64 *);

int read_current_timer(unsigned long *timer_val);
void ntp_notify_cmos_timer(void);
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index df68cb875248..bd4fa6271262 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -99,7 +99,7 @@ static time64_t ntp_next_leap_sec = TIME64_MAX;
static int pps_valid; /* signal watchdog counter */
static long pps_tf[3]; /* phase median filter */
static long pps_jitter; /* current jitter (ns) */
-static struct timespec pps_fbase; /* beginning of the last freq interval */
+static struct timespec64 pps_fbase; /* beginning of the last freq interval */
static int pps_shift; /* current interval duration (s) (shift) */
static int pps_intcnt; /* interval counter */
static s64 pps_freq; /* frequency offset (scaled ns/s) */
@@ -773,13 +773,13 @@ int __do_adjtimex(struct timex *txc, struct timespec64 *ts, s32 *time_tai)
* pps_normtime.nsec has a range of ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ]
* while timespec.tv_nsec has a range of [0, NSEC_PER_SEC) */
struct pps_normtime {
- __kernel_time_t sec; /* seconds */
+ s64 sec; /* seconds */
long nsec; /* nanoseconds */
};

/* normalize the timestamp so that nsec is in the
( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] interval */
-static inline struct pps_normtime pps_normalize_ts(struct timespec ts)
+static inline struct pps_normtime pps_normalize_ts(struct timespec64 ts)
{
struct pps_normtime norm = {
.sec = ts.tv_sec,
@@ -861,7 +861,7 @@ static long hardpps_update_freq(struct pps_normtime freq_norm)
pps_errcnt++;
pps_dec_freq_interval();
printk_deferred(KERN_ERR
- "hardpps: PPSERROR: interval too long - %ld s\n",
+ "hardpps: PPSERROR: interval too long - %lld s\n",
freq_norm.sec);
return 0;
}
@@ -948,7 +948,7 @@ static void hardpps_update_phase(long error)
* This code is based on David Mills's reference nanokernel
* implementation. It was mostly rewritten but keeps the same idea.
*/
-void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
+void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)
{
struct pps_normtime pts_norm, freq_norm;

@@ -969,7 +969,7 @@ void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
}

/* ok, now we have a base for frequency calculation */
- freq_norm = pps_normalize_ts(timespec_sub(*raw_ts, pps_fbase));
+ freq_norm = pps_normalize_ts(timespec64_sub(*raw_ts, pps_fbase));

/* check that the signal is in the range
* [1s - MAXFREQ us, 1s + MAXFREQ us], otherwise reject it */
diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h
index 65430504ca26..af924470eac0 100644
--- a/kernel/time/ntp_internal.h
+++ b/kernel/time/ntp_internal.h
@@ -9,5 +9,5 @@ extern ktime_t ntp_get_next_leap(void);
extern int second_overflow(unsigned long secs);
extern int ntp_validate_timex(struct timex *);
extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *);
-extern void __hardpps(const struct timespec *, const struct timespec *);
+extern void __hardpps(const struct timespec64 *, const struct timespec64 *);
#endif /* _LINUX_NTP_INTERNAL_H */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 9a7f3b788282..3112977dfca0 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -2025,7 +2025,7 @@ int do_adjtimex(struct timex *txc)
/**
* hardpps() - Accessor function to NTP __hardpps function
*/
-void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
+void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)
{
unsigned long flags;

--
2.1.0.rc2