tty: add throttle/unthrottle helpers
Something Arjan suggested which allows us to clean up the code nicely
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index c10d40c..b1a757a 100644
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -67,6 +67,22 @@
EXPORT_SYMBOL(tty_driver_flush_buffer);
+void tty_throttle(struct tty_struct *tty)
+{
+ /* check TTY_THROTTLED first so it indicates our state */
+ if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
+ tty->ops->throttle)
+ tty->ops->throttle(tty);
+}
+EXPORT_SYMBOL(tty_throttle);
+
+void tty_unthrottle(struct tty_struct *tty)
+{
+ if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
+ tty->ops->unthrottle)
+ tty->ops->unthrottle(tty);
+}
+EXPORT_SYMBOL(tty_unthrottle);
/**
* tty_wait_until_sent - wait for I/O to finish