tty: moxa: Kill the use of lock_kernel

[safe/jmp/linux-2.6] / drivers / char / tty_io.c

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 9384480..59499ee 100644 (file)
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -1184,6 +1184,7 @@ int tty_init_termios(struct tty_struct *tty)
        tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios);
        return 0;
 }
+EXPORT_SYMBOL_GPL(tty_init_termios);
 
 /**
  *     tty_driver_install_tty() - install a tty entry in the driver
@@ -1386,16 +1387,19 @@ EXPORT_SYMBOL(tty_shutdown);
  *             tty_mutex - sometimes only
  *             takes the file list lock internally when working on the list
  *     of ttys that the driver keeps.
+ *
+ *     This method gets called from a work queue so that the driver private
+ *     cleanup ops can sleep (needed for USB at least)
  */
-static void release_one_tty(struct kref *kref)
+static void release_one_tty(struct work_struct *work)
 {
-       struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
+       struct tty_struct *tty =
+               container_of(work, struct tty_struct, hangup_work);
        struct tty_driver *driver = tty->driver;
 
-       if (tty->ops->shutdown)
-               tty->ops->shutdown(tty);
-       else
-               tty_shutdown(tty);
+       if (tty->ops->cleanup)
+               tty->ops->cleanup(tty);
+
        tty->magic = 0;
        tty_driver_kref_put(driver);
        module_put(driver->owner);
@@ -1407,6 +1411,21 @@ static void release_one_tty(struct kref *kref)
        free_tty_struct(tty);
 }
 
+static void queue_release_one_tty(struct kref *kref)
+{
+       struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
+
+       if (tty->ops->shutdown)
+               tty->ops->shutdown(tty);
+       else
+               tty_shutdown(tty);
+
+       /* The hangup queue is now free so we can reuse it rather than
+          waste a chunk of memory for each port */
+       INIT_WORK(&tty->hangup_work, release_one_tty);
+       schedule_work(&tty->hangup_work);
+}
+
 /**
  *     tty_kref_put            -       release a tty kref
  *     @tty: tty device
@@ -1418,7 +1437,7 @@ static void release_one_tty(struct kref *kref)
 void tty_kref_put(struct tty_struct *tty)
 {
        if (tty)
-               kref_put(&tty->kref, release_one_tty);
+               kref_put(&tty->kref, queue_release_one_tty);
 }
 EXPORT_SYMBOL(tty_kref_put);
 
@@ -3056,11 +3075,22 @@ void __init console_init(void)
        }
 }
 
+static char *tty_devnode(struct device *dev, mode_t *mode)
+{
+       if (!mode)
+               return NULL;
+       if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) ||
+           dev->devt == MKDEV(TTYAUX_MAJOR, 2))
+               *mode = 0666;
+       return NULL;
+}
+
 static int __init tty_class_init(void)
 {
        tty_class = class_create(THIS_MODULE, "tty");
        if (IS_ERR(tty_class))
                return PTR_ERR(tty_class);
+       tty_class->devnode = tty_devnode;
        return 0;
 }