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, 13 insertions, 22 deletions

diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index f96b91da964f..b00e5cbf741f 100644
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -232,8 +232,8 @@ static void  process_rcvd_data(struct edgeport_serial *edge_serial,
                                 unsigned char *buffer, __u16 bufferLength);
 static void process_rcvd_status(struct edgeport_serial *edge_serial,
                                 __u8 byte2, __u8 byte3);
-static void edge_tty_recv(struct usb_serial_port *port, struct tty_struct *tty,
-                                unsigned char *data, int length);
+static void edge_tty_recv(struct usb_serial_port *port, unsigned char *data,
+                int length);
 static void handle_new_msr(struct edgeport_port *edge_port, __u8 newMsr);
 static void handle_new_lsr(struct edgeport_port *edge_port, __u8 lsrData,
                                 __u8 lsr, __u8 data);
@@ -1752,7 +1752,6 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
         struct device *dev = &edge_serial->serial->dev->dev;
         struct usb_serial_port *port;
         struct edgeport_port *edge_port;
-        struct tty_struct *tty;
         __u16 lastBufferLength;
         __u16 rxLen;
 
@@ -1860,14 +1859,11 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
                                                         edge_serial->rxPort];
                                 edge_port = usb_get_serial_port_data(port);
                                 if (edge_port->open) {
-                                        tty = tty_port_tty_get(
-                                                &edge_port->port->port);
-                                        if (tty) {
-                                                dev_dbg(dev, "%s - Sending %d bytes to TTY for port %d\n",
-                                                        __func__, rxLen, edge_serial->rxPort);
-                                                edge_tty_recv(edge_port->port, tty, buffer, rxLen);
-                                                tty_kref_put(tty);
-                                        }
+                                        dev_dbg(dev, "%s - Sending %d bytes to TTY for port %d\n",
+                                                __func__, rxLen,
+                                                edge_serial->rxPort);
+                                        edge_tty_recv(edge_port->port, buffer,
+                                                        rxLen);
                                         edge_port->icount.rx += rxLen;
                                 }
                                 buffer += rxLen;
@@ -2017,8 +2013,8 @@ static void process_rcvd_status(struct edgeport_serial *edge_serial,
  * edge_tty_recv
  *      this function passes data on to the tty flip buffer
  *****************************************************************************/
-static void edge_tty_recv(struct usb_serial_port *port, struct tty_struct *tty,
-                                        unsigned char *data, int length)
+static void edge_tty_recv(struct usb_serial_port *port, unsigned char *data,
+                int length)
 {
         int cnt;
 
@@ -2030,7 +2026,7 @@ static void edge_tty_recv(struct usb_serial_port *port, struct tty_struct *tty,
         data += cnt;
         length -= cnt;
 
-        tty_flip_buffer_push(tty);
+        tty_flip_buffer_push(&port->port);
 }
 
 
@@ -2086,14 +2082,9 @@ static void handle_new_lsr(struct edgeport_port *edge_port, __u8 lsrData,
         }
 
         /* Place LSR data byte into Rx buffer */
-        if (lsrData) {
-                struct tty_struct *tty =
-                                tty_port_tty_get(&edge_port->port->port);
-                if (tty) {
-                        edge_tty_recv(edge_port->port, tty, &data, 1);
-                        tty_kref_put(tty);
-                }
-        }
+        if (lsrData)
+                edge_tty_recv(edge_port->port, &data, 1);
+
         /* update input line counters */
         icount = &edge_port->icount;
         if (newLsr & LSR_BREAK)