---

yaml
---
r: 56313
b: refs/heads/master
c: c5c34d4
h: refs/heads/master
i:
  56311: 544f854
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e3bf460f3eb86cdbc76725a0dac1f191e796676c
+refs/heads/master: c5c34d4862e18ef07c1276d233507f540fb5a532

trunk/drivers/char/tty_io.c

@@ -368,6 +368,29 @@ static void tty_buffer_free(struct tty_struct *tty, struct tty_buffer *b)
 	}
 }
 
+/**
+ *	tty_buffer_flush		-	flush full tty buffers
+ *	@tty: tty to flush
+ *
+ *	flush all the buffers containing receive data
+ *
+ *	Locking: none
+ */
+
+static void tty_buffer_flush(struct tty_struct *tty)
+{
+	struct tty_buffer *thead;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tty->buf.lock, flags);
+	while((thead = tty->buf.head) != NULL) {
+		tty->buf.head = thead->next;
+		tty_buffer_free(tty, thead);
+	}
+	tty->buf.tail = NULL;
+	spin_unlock_irqrestore(&tty->buf.lock, flags);
+}
+
 /**
  *	tty_buffer_find		-	find a free tty buffer
  *	@tty: tty owning the buffer
@@ -1248,6 +1271,7 @@ void tty_ldisc_flush(struct tty_struct *tty)
 			ld->flush_buffer(tty);
 		tty_ldisc_deref(ld);
 	}
+	tty_buffer_flush(tty);
 }
 
 EXPORT_SYMBOL_GPL(tty_ldisc_flush);
@@ -3350,6 +3374,15 @@ int tty_ioctl(struct inode * inode, struct file * file,
 		case TIOCMBIC:
 		case TIOCMBIS:
 			return tty_tiocmset(tty, file, cmd, p);
+		case TCFLSH:
+			switch (arg) {
+			case TCIFLUSH:
+			case TCIOFLUSH:
+				/* flush tty buffer and allow ldisc to process ioctl */
+				tty_buffer_flush(tty);
+				break;
+			}
+			break;
 	}
 	if (tty->driver->ioctl) {
 		retval = (tty->driver->ioctl)(tty, file, cmd, arg);