staging/lustre: use 64-bit time for adaptive timeout

The adaptive timeout handling stores absolute times in 32-bit time_t
quantities, which will overflow in 2038.

This changes it to use time64_t.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/include/lustre_import.h

@@ -61,12 +61,12 @@
 #define AT_FLG_NOHIST 0x1	  /* use last reported value only */
 
 struct adaptive_timeout {
-	time_t		at_binstart;	 /* bin start time */
+	time64_t	at_binstart;	 /* bin start time */
 	unsigned int	at_hist[AT_BINS];    /* timeout history bins */
 	unsigned int	at_flags;
 	unsigned int	at_current;	  /* current timeout value */
 	unsigned int	at_worst_ever;       /* worst-ever timeout value */
-	time_t		at_worst_time;       /* worst-ever timeout timestamp */
+	time64_t	at_worst_time;       /* worst-ever timeout timestamp */
 	spinlock_t	at_lock;
 };
 
@@ -351,7 +351,7 @@ static inline void at_reset(struct adaptive_timeout *at, int val)
 	spin_lock(&at->at_lock);
 	at->at_current = val;
 	at->at_worst_ever = val;
-	at->at_worst_time = get_seconds();
+	at->at_worst_time = ktime_get_real_seconds();
 	spin_unlock(&at->at_lock);
 }
 static inline void at_init(struct adaptive_timeout *at, int val, int flags)

drivers/staging/lustre/lustre/ptlrpc/import.c

@@ -1523,12 +1523,12 @@ extern unsigned int at_min, at_max, at_history;
 int at_measured(struct adaptive_timeout *at, unsigned int val)
 {
 	unsigned int old = at->at_current;
-	time_t now = get_seconds();
-	time_t binlimit = max_t(time_t, at_history / AT_BINS, 1);
+	time64_t now = ktime_get_real_seconds();
+	long binlimit = max_t(long, at_history / AT_BINS, 1);
 
 	LASSERT(at);
 	CDEBUG(D_OTHER, "add %u to %p time=%lu v=%u (%u %u %u %u)\n",
-	       val, at, now - at->at_binstart, at->at_current,
+	       val, at, (long)(now - at->at_binstart), at->at_current,
 	       at->at_hist[0], at->at_hist[1], at->at_hist[2], at->at_hist[3]);
 
 	if (val == 0)
@@ -1553,7 +1553,7 @@ int at_measured(struct adaptive_timeout *at, unsigned int val)
 		int i, shift;
 		unsigned int maxv = val;
 		/* move bins over */
-		shift = (now - at->at_binstart) / binlimit;
+		shift = (u32)(now - at->at_binstart) / binlimit;
 		LASSERT(shift > 0);
 		for (i = AT_BINS - 1; i >= 0; i--) {
 			if (i >= shift) {

drivers/staging/lustre/lustre/ptlrpc/lproc_ptlrpc.c

@@ -989,7 +989,7 @@ static int ptlrpc_lprocfs_timeouts_seq_show(struct seq_file *m, void *n)
 	struct ptlrpc_service *svc = m->private;
 	struct ptlrpc_service_part *svcpt;
 	struct dhms ts;
-	time_t worstt;
+	time64_t worstt;
 	unsigned int cur;
 	unsigned int worst;
 	int i;
@@ -1004,11 +1004,11 @@ static int ptlrpc_lprocfs_timeouts_seq_show(struct seq_file *m, void *n)
 		cur	= at_get(&svcpt->scp_at_estimate);
 		worst	= svcpt->scp_at_estimate.at_worst_ever;
 		worstt	= svcpt->scp_at_estimate.at_worst_time;
-		s2dhms(&ts, get_seconds() - worstt);
+		s2dhms(&ts, ktime_get_real_seconds() - worstt);
 
-		seq_printf(m, "%10s : cur %3u  worst %3u (at %ld, "
+		seq_printf(m, "%10s : cur %3u  worst %3u (at %lld, "
 			      DHMS_FMT" ago) ", "service",
-			      cur, worst, worstt, DHMS_VARS(&ts));
+			      cur, worst, (s64)worstt, DHMS_VARS(&ts));
 
 		lprocfs_at_hist_helper(m, &svcpt->scp_at_estimate);
 	}