TTY: switch tty_flip_buffer_push

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 11 deletions

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 9ab910370c5..82a3151e393 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -147,15 +147,11 @@
 static irqreturn_t xuartps_isr(int irq, void *dev_id)
 {
 	struct uart_port *port = (struct uart_port *)dev_id;
-	struct tty_struct *tty;
 	unsigned long flags;
 	unsigned int isrstatus, numbytes;
 	unsigned int data;
 	char status = TTY_NORMAL;
 
-	/* Get the tty which could be NULL so don't assume it's valid */
-	tty = tty_port_tty_get(&port->state->port);
-
 	spin_lock_irqsave(&port->lock, flags);
 
 	/* Read the interrupt status register to determine which
@@ -187,14 +183,11 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
 			} else if (isrstatus & XUARTPS_IXR_OVERRUN)
 				port->icount.overrun++;
 
-			if (tty)
-				uart_insert_char(port, isrstatus,
-						XUARTPS_IXR_OVERRUN, data,
-						status);
+			uart_insert_char(port, isrstatus, XUARTPS_IXR_OVERRUN,
+					data, status);
 		}
 		spin_unlock(&port->lock);
-		if (tty)
-			tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&port->state->port);
 		spin_lock(&port->lock);
 	}
 
@@ -237,7 +230,6 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
 
 	/* be sure to release the lock and tty before leaving */
 	spin_unlock_irqrestore(&port->lock, flags);
-	tty_kref_put(tty);
 
 	return IRQ_HANDLED;
 }