tty: Replace ASYNC_NORMAL_ACTIVE bit and update atomically

Replace ASYNC_NORMAL_ACTIVE bit in the tty_port::flags field with
TTY_PORT_ACTIVE bit in the tty_port::iflags field. Introduce helpers
tty_port_set_active() and tty_port_active() to abstract atomic bit ops.

Extract state changes from port lock sections, as this usage is
broken and confused; the state transitions are protected by the
tty lock (which mutually excludes parallel open/close/hangup),
and no user tests the active state while holding the port lock.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/net/irda/ircomm/ircomm_tty.c b/net/irda/ircomm/ircomm_tty.c
index 840b82f760ba..681fe0bfe558 100644
--- a/net/irda/ircomm/ircomm_tty.c
+++ b/net/irda/ircomm/ircomm_tty.c
@@ -281,7 +281,7 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
          * then make the check up front and then exit.
          */
         if (tty_io_error(tty)) {
-                port->flags |= ASYNC_NORMAL_ACTIVE;
+                tty_port_set_active(port, 1);
                 return 0;
         }
 
@@ -289,7 +289,7 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
                 /* nonblock mode is set */
                 if (C_BAUD(tty))
                         tty_port_raise_dtr_rts(port);
-                port->flags |= ASYNC_NORMAL_ACTIVE;
+                tty_port_set_active(port, 1);
                 pr_debug("%s(), O_NONBLOCK requested!\n", __func__);
                 return 0;
         }
@@ -365,7 +365,7 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
                  __FILE__, __LINE__, tty->driver->name, port->count);
 
         if (!retval)
-                port->flags |= ASYNC_NORMAL_ACTIVE;
+                tty_port_set_active(port, 1);
 
         return retval;
 }
@@ -925,7 +925,6 @@ static void ircomm_tty_hangup(struct tty_struct *tty)
         ircomm_tty_shutdown(self);
 
         spin_lock_irqsave(&port->lock, flags);
-        port->flags &= ~ASYNC_NORMAL_ACTIVE;
         if (port->tty) {
                 set_bit(TTY_IO_ERROR, &port->tty->flags);
                 tty_kref_put(port->tty);
@@ -933,6 +932,7 @@ static void ircomm_tty_hangup(struct tty_struct *tty)
         port->tty = NULL;
         port->count = 0;
         spin_unlock_irqrestore(&port->lock, flags);
+        tty_port_set_active(port, 0);
 
         wake_up_interruptible(&port->open_wait);
 }
@@ -1267,7 +1267,7 @@ static void ircomm_tty_line_info(struct ircomm_tty_cb *self, struct seq_file *m)
                 seq_printf(m, "%cASYNC_LOW_LATENCY", sep);
                 sep = '|';
         }
-        if (self->port.flags & ASYNC_NORMAL_ACTIVE) {
+        if (tty_port_active(&self->port)) {
                 seq_printf(m, "%cASYNC_NORMAL_ACTIVE", sep);
                 sep = '|';
         }