serial: 8250_omap: check how many bytes were injected

The function tty_insert_flip_string() returns an int and as such it
might fail. So the result is that I kindly asked to insert 48 bytes and
the function only insterted 32.
I have no idea what to do with the remaining 16 so I think dropping them
is the only option. I also increase the buf_overrun counter so userpace
has a clue that we lost bytes.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sebastian Andrzej Siewior 2015-08-14 18:01:03 +02:00 committed by Greg Kroah-Hartman
parent 9ffecb1028
commit 658e2ebce5

View file

@ -726,6 +726,7 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error)
struct dma_tx_state state;
int count;
unsigned long flags;
int ret;
dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr,
dma->rx_size, DMA_FROM_DEVICE);
@ -741,8 +742,10 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error)
count = dma->rx_size - state.residue;
tty_insert_flip_string(tty_port, dma->rx_buf, count);
p->port.icount.rx += count;
ret = tty_insert_flip_string(tty_port, dma->rx_buf, count);
p->port.icount.rx += ret;
p->port.icount.buf_overrun += count - ret;
unlock:
spin_unlock_irqrestore(&priv->rx_dma_lock, flags);