[PATCH v2 2/3] tty: new helper function tty_get_icount()

[Uwe Kleine-KÃnig]

For a given struct tty_struct this yields the corresponding statistics
about sent and received characters (and some more)

Use the function to simplify tty_tiocgicount().

Signed-off-by: Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx>
---
 drivers/tty/tty_io.c | 20 ++++++++++++++++----
 include/linux/tty.h  |  2 ++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 584025117cd3..df3942eb3468 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2497,15 +2497,27 @@ static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd,
 	return tty->ops->tiocmset(tty, set, clear);
 }
 
+int tty_get_icount(struct tty_struct *tty,
+		   struct serial_icounter_struct *icount)
+{
+	memset(icount, 0, sizeof(*icount));
+
+	if (tty->ops->get_icount)
+		return tty->ops->get_icount(tty, icount);
+	else
+		return -EINVAL;
+}
+EXPORT_SYMBOL(tty_get_icount);
+
 static int tty_tiocgicount(struct tty_struct *tty, void __user *arg)
 {
-	int retval = -EINVAL;
 	struct serial_icounter_struct icount;
-	memset(&icount, 0, sizeof(icount));
-	if (tty->ops->get_icount)
-		retval = tty->ops->get_icount(tty, &icount);
+	int retval;
+
+	retval = tty_get_icount(tty, &icount);
 	if (retval != 0)
 		return retval;
+
 	if (copy_to_user(arg, &icount, sizeof(icount)))
 		return -EFAULT;
 	return 0;
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 616268eb1613..3c6f58032f57 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -495,6 +495,8 @@ extern void tty_unthrottle(struct tty_struct *tty);
 extern int tty_throttle_safe(struct tty_struct *tty);
 extern int tty_unthrottle_safe(struct tty_struct *tty);
 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
+extern int tty_get_icount(struct tty_struct *tty,
+			  struct serial_icounter_struct *icount);
 extern int is_current_pgrp_orphaned(void);
 extern void tty_hangup(struct tty_struct *tty);
 extern void tty_vhangup(struct tty_struct *tty);
-- 
2.24.0