fs: poll/select/recvmmsg: use timespec64 for timeout events

struct timespec is not y2038 safe.  Even though timespec might be
sufficient to represent timeouts, use struct timespec64 here as the plan
is to get rid of all timespec reference in the kernel.

The patch transitions the common functions: poll_select_set_timeout()
and select_estimate_accuracy() to use timespec64.  And, all the syscalls
that use these functions are transitioned in the same patch.

The restart block parameters for poll uses monotonic time.  Use
timespec64 here as well to assign timeout value.  This parameter in the
restart block need not change because this only holds the monotonic
timestamp at which timeout should occur.  And, unsigned long data type
should be big enough for this timestamp.

The system call interfaces will be handled in a separate series.

Compat interfaces need not change as timespec64 is an alias to struct
timespec on a 64 bit system.

Link: http://lkml.kernel.org/r/1461947989-21926-3-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 8a74a2a..10db912 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1583,15 +1583,15 @@
 	return ep_scan_ready_list(ep, ep_send_events_proc, &esed, 0, false);
 }
 
-static inline struct timespec ep_set_mstimeout(long ms)
+static inline struct timespec64 ep_set_mstimeout(long ms)
 {
-	struct timespec now, ts = {
+	struct timespec64 now, ts = {
 		.tv_sec = ms / MSEC_PER_SEC,
 		.tv_nsec = NSEC_PER_MSEC * (ms % MSEC_PER_SEC),
 	};
 
-	ktime_get_ts(&now);
-	return timespec_add_safe(now, ts);
+	ktime_get_ts64(&now);
+	return timespec64_add_safe(now, ts);
 }
 
 /**
@@ -1621,11 +1621,11 @@
 	ktime_t expires, *to = NULL;
 
 	if (timeout > 0) {
-		struct timespec end_time = ep_set_mstimeout(timeout);
+		struct timespec64 end_time = ep_set_mstimeout(timeout);
 
 		slack = select_estimate_accuracy(&end_time);
 		to = &expires;
-		*to = timespec_to_ktime(end_time);
+		*to = timespec64_to_ktime(end_time);
 	} else if (timeout == 0) {
 		/*
 		 * Avoid the unnecessary trip to the wait queue loop, if the
diff --git a/fs/select.c b/fs/select.c
index 8692939..8ed9da5 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -47,7 +47,7 @@
 
 #define MAX_SLACK	(100 * NSEC_PER_MSEC)
 
-static long __estimate_accuracy(struct timespec *tv)
+static long __estimate_accuracy(struct timespec64 *tv)
 {
 	long slack;
 	int divfactor = 1000;
@@ -70,10 +70,10 @@
 	return slack;
 }
 
-u64 select_estimate_accuracy(struct timespec *tv)
+u64 select_estimate_accuracy(struct timespec64 *tv)
 {
 	u64 ret;
-	struct timespec now;
+	struct timespec64 now;
 
 	/*
 	 * Realtime tasks get a slack of 0 for obvious reasons.
@@ -82,8 +82,8 @@
 	if (rt_task(current))
 		return 0;
 
-	ktime_get_ts(&now);
-	now = timespec_sub(*tv, now);
+	ktime_get_ts64(&now);
+	now = timespec64_sub(*tv, now);
 	ret = __estimate_accuracy(&now);
 	if (ret < current->timer_slack_ns)
 		return current->timer_slack_ns;
@@ -260,7 +260,7 @@
 
 /**
  * poll_select_set_timeout - helper function to setup the timeout value
- * @to:		pointer to timespec variable for the final timeout
+ * @to:		pointer to timespec64 variable for the final timeout
  * @sec:	seconds (from user space)
  * @nsec:	nanoseconds (from user space)
  *
@@ -269,26 +269,28 @@
  *
  * Returns -EINVAL if sec/nsec are not normalized. Otherwise 0.
  */
-int poll_select_set_timeout(struct timespec *to, long sec, long nsec)
+int poll_select_set_timeout(struct timespec64 *to, time64_t sec, long nsec)
 {
-	struct timespec ts = {.tv_sec = sec, .tv_nsec = nsec};
+	struct timespec64 ts = {.tv_sec = sec, .tv_nsec = nsec};
 
-	if (!timespec_valid(&ts))
+	if (!timespec64_valid(&ts))
 		return -EINVAL;
 
 	/* Optimize for the zero timeout value here */
 	if (!sec && !nsec) {
 		to->tv_sec = to->tv_nsec = 0;
 	} else {
-		ktime_get_ts(to);
-		*to = timespec_add_safe(*to, ts);
+		ktime_get_ts64(to);
+		*to = timespec64_add_safe(*to, ts);
 	}
 	return 0;
 }
 
-static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
+static int poll_select_copy_remaining(struct timespec64 *end_time,
+				      void __user *p,
 				      int timeval, int ret)
 {
+	struct timespec64 rts64;
 	struct timespec rts;
 	struct timeval rtv;
 
@@ -302,16 +304,18 @@
 	if (!end_time->tv_sec && !end_time->tv_nsec)
 		return ret;
 
-	ktime_get_ts(&rts);
-	rts = timespec_sub(*end_time, rts);
-	if (rts.tv_sec < 0)
-		rts.tv_sec = rts.tv_nsec = 0;
+	ktime_get_ts64(&rts64);
+	rts64 = timespec64_sub(*end_time, rts64);
+	if (rts64.tv_sec < 0)
+		rts64.tv_sec = rts64.tv_nsec = 0;
+
+	rts = timespec64_to_timespec(rts64);
 
 	if (timeval) {
 		if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec))
 			memset(&rtv, 0, sizeof(rtv));
-		rtv.tv_sec = rts.tv_sec;
-		rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
+		rtv.tv_sec = rts64.tv_sec;
+		rtv.tv_usec = rts64.tv_nsec / NSEC_PER_USEC;
 
 		if (!copy_to_user(p, &rtv, sizeof(rtv)))
 			return ret;
@@ -396,7 +400,7 @@
 		wait->_key |= POLLOUT_SET;
 }
 
-int do_select(int n, fd_set_bits *fds, struct timespec *end_time)
+int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time)
 {
 	ktime_t expire, *to = NULL;
 	struct poll_wqueues table;
@@ -522,7 +526,7 @@
 		 * pointer to the expiry value.
 		 */
 		if (end_time && !to) {
-			expire = timespec_to_ktime(*end_time);
+			expire = timespec64_to_ktime(*end_time);
 			to = &expire;
 		}
 
@@ -545,7 +549,7 @@
  * I'm trying ERESTARTNOHAND which restart only when you want to.
  */
 int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
-			   fd_set __user *exp, struct timespec *end_time)
+			   fd_set __user *exp, struct timespec64 *end_time)
 {
 	fd_set_bits fds;
 	void *bits;
@@ -622,7 +626,7 @@
 SYSCALL_DEFINE5(select, int, n, fd_set __user *, inp, fd_set __user *, outp,
 		fd_set __user *, exp, struct timeval __user *, tvp)
 {
-	struct timespec end_time, *to = NULL;
+	struct timespec64 end_time, *to = NULL;
 	struct timeval tv;
 	int ret;
 
@@ -648,15 +652,17 @@
 		       const sigset_t __user *sigmask, size_t sigsetsize)
 {
 	sigset_t ksigmask, sigsaved;
-	struct timespec ts, end_time, *to = NULL;
+	struct timespec ts;
+	struct timespec64 ts64, end_time, *to = NULL;
 	int ret;
 
 	if (tsp) {
 		if (copy_from_user(&ts, tsp, sizeof(ts)))
 			return -EFAULT;
+		ts64 = timespec_to_timespec64(ts);
 
 		to = &end_time;
-		if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
+		if (poll_select_set_timeout(to, ts64.tv_sec, ts64.tv_nsec))
 			return -EINVAL;
 	}
 
@@ -779,7 +785,7 @@
 }
 
 static int do_poll(struct poll_list *list, struct poll_wqueues *wait,
-		   struct timespec *end_time)
+		   struct timespec64 *end_time)
 {
 	poll_table* pt = &wait->pt;
 	ktime_t expire, *to = NULL;
@@ -854,7 +860,7 @@
 		 * pointer to the expiry value.
 		 */
 		if (end_time && !to) {
-			expire = timespec_to_ktime(*end_time);
+			expire = timespec64_to_ktime(*end_time);
 			to = &expire;
 		}
 
@@ -868,7 +874,7 @@
 			sizeof(struct pollfd))
 
 int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
-		struct timespec *end_time)
+		struct timespec64 *end_time)
 {
 	struct poll_wqueues table;
  	int err = -EFAULT, fdcount, len, size;
@@ -936,7 +942,7 @@
 {
 	struct pollfd __user *ufds = restart_block->poll.ufds;
 	int nfds = restart_block->poll.nfds;
-	struct timespec *to = NULL, end_time;
+	struct timespec64 *to = NULL, end_time;
 	int ret;
 
 	if (restart_block->poll.has_timeout) {
@@ -957,7 +963,7 @@
 SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
 		int, timeout_msecs)
 {
-	struct timespec end_time, *to = NULL;
+	struct timespec64 end_time, *to = NULL;
 	int ret;
 
 	if (timeout_msecs >= 0) {
@@ -993,7 +999,8 @@
 		size_t, sigsetsize)
 {
 	sigset_t ksigmask, sigsaved;
-	struct timespec ts, end_time, *to = NULL;
+	struct timespec ts;
+	struct timespec64 end_time, *to = NULL;
 	int ret;
 
 	if (tsp) {
diff --git a/include/linux/poll.h b/include/linux/poll.h
index 9fb4f40..37b057b 100644
--- a/include/linux/poll.h
+++ b/include/linux/poll.h
@@ -96,7 +96,7 @@
 extern void poll_freewait(struct poll_wqueues *pwq);
 extern int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
 				 ktime_t *expires, unsigned long slack);
-extern u64 select_estimate_accuracy(struct timespec *tv);
+extern u64 select_estimate_accuracy(struct timespec64 *tv);
 
 
 static inline int poll_schedule(struct poll_wqueues *pwq, int state)
@@ -153,12 +153,13 @@
 
 #define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1)
 
-extern int do_select(int n, fd_set_bits *fds, struct timespec *end_time);
+extern int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time);
 extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds,
-		       struct timespec *end_time);
+		       struct timespec64 *end_time);
 extern int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
-			   fd_set __user *exp, struct timespec *end_time);
+			   fd_set __user *exp, struct timespec64 *end_time);
 
-extern int poll_select_set_timeout(struct timespec *to, long sec, long nsec);
+extern int poll_select_set_timeout(struct timespec64 *to, time64_t sec,
+				   long nsec);
 
 #endif /* _LINUX_POLL_H */
diff --git a/net/socket.c b/net/socket.c
index e7793f5..a1bd161 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2168,7 +2168,8 @@
 	struct mmsghdr __user *entry;
 	struct compat_mmsghdr __user *compat_entry;
 	struct msghdr msg_sys;
-	struct timespec end_time;
+	struct timespec64 end_time;
+	struct timespec64 timeout64;
 
 	if (timeout &&
 	    poll_select_set_timeout(&end_time, timeout->tv_sec,
@@ -2220,8 +2221,9 @@
 			flags |= MSG_DONTWAIT;
 
 		if (timeout) {
-			ktime_get_ts(timeout);
-			*timeout = timespec_sub(end_time, *timeout);
+			ktime_get_ts64(&timeout64);
+			*timeout = timespec64_to_timespec(
+					timespec64_sub(end_time, timeout64));
 			if (timeout->tv_sec < 0) {
 				timeout->tv_sec = timeout->tv_nsec = 0;
 				break;