diff options
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/tty_io.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index bc849957508..75d2a46e106 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -369,6 +369,29 @@ 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 * @size: characters wanted @@ -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); |