tty: tty_port: Add a kref object to the tty port

[safe/jmp/linux-2.6] / include / linux / tty.h

diff --git a/include/linux/tty.h b/include/linux/tty.h
index e9269ca..e6da667 100644 (file)
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -199,6 +199,8 @@ struct tty_port_operations {
         /* FIXME: long term getting the tty argument *out* of this would be
            good for consoles */
        int (*activate)(struct tty_port *port, struct tty_struct *tty);
+       /* Called on the final put of a port */
+       void (*destruct)(struct tty_port *port);
 };
        
 struct tty_port {
@@ -219,6 +221,7 @@ struct tty_port {
        int                     drain_delay;    /* Set to zero if no pure time
                                                   based drain is needed else
                                                   set to size of fifo */
+       struct kref             kref;           /* Ref counter */
 };
 
 /*
@@ -461,6 +464,15 @@ extern int tty_write_lock(struct tty_struct *tty, int ndelay);
 extern void tty_port_init(struct tty_port *port);
 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
 extern void tty_port_free_xmit_buf(struct tty_port *port);
+extern void tty_port_put(struct tty_port *port);
+
+extern inline struct tty_port *tty_port_get(struct tty_port *port)
+{
+       if (port)
+               kref_get(&port->kref);
+       return port;
+}
+
 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
 extern int tty_port_carrier_raised(struct tty_port *port);