USB: usb-serial: Prepare for BKL push down

Take the lock in usb-serial instead. As it relies on the BKL internally
we can't push it any deeper yet.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 2138ba8aeb697b2e35ee04d5e62e6f008bdb0c47..aea861e9173e89f7742ce2d2076a70ff6a3e4126 100644 (file)
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -401,11 +401,13 @@ static int serial_ioctl (struct tty_struct *tty, struct file * file, unsigned in
        struct usb_serial_port *port = tty->driver_data;
        int retval = -ENODEV;
 
+       lock_kernel();
        if (!port)
                goto exit;
 
        dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
 
+       /* Caution - port->open_count is BKL protected */
        if (!port->open_count) {
                dbg ("%s - port not open", __FUNCTION__);
                goto exit;
@@ -416,8 +418,8 @@ static int serial_ioctl (struct tty_struct *tty, struct file * file, unsigned in
                retval = port->serial->type->ioctl(port, file, cmd, arg);
        else
                retval = -ENOIOCTLCMD;
-
 exit:
+       unlock_kernel();
        return retval;
 }
 
@@ -446,19 +448,24 @@ static void serial_break (struct tty_struct *tty, int break_state)
 {
        struct usb_serial_port *port = tty->driver_data;
 
-       if (!port)
+       lock_kernel();
+       if (!port) {
+               unlock_kernel();
                return;
+       }
 
        dbg("%s - port %d", __FUNCTION__, port->number);
 
        if (!port->open_count) {
                dbg("%s - port not open", __FUNCTION__);
+               unlock_kernel();
                return;
        }
 
        /* pass on to the driver specific version of this function if it is available */
        if (port->serial->type->break_ctl)
                port->serial->type->break_ctl(port, break_state);
+       unlock_kernel();
 }
 
 static int serial_read_proc (char *page, char **start, off_t off, int count, int *eof, void *data)