tty: relock riscom8 using port locks
Alan Cox [Fri, 2 Jan 2009 13:45:50 +0000 (13:45 +0000)]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/riscom8.c

index 6ad1c2a..14662d7 100644 (file)
@@ -919,14 +919,12 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
        retval = 0;
        add_wait_queue(&port->open_wait, &wait);
 
-       spin_lock_irqsave(&riscom_lock, flags);
-
+       spin_lock_irqsave(&port->lock, flags);
        if (!tty_hung_up_p(filp))
                port->count--;
-
-       spin_unlock_irqrestore(&riscom_lock, flags);
-
        port->blocked_open++;
+       spin_unlock_irqrestore(&port->lock, flags);
+
        while (1) {
 
                CD = tty_port_carrier_raised(port);
@@ -950,13 +948,13 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
        }
        __set_current_state(TASK_RUNNING);
        remove_wait_queue(&port->open_wait, &wait);
+       spin_lock_irqsave(&port->lock, flags);
        if (!tty_hung_up_p(filp))
                port->count++;
        port->blocked_open--;
-       if (retval)
-               return retval;
-
-       port->flags |= ASYNC_NORMAL_ACTIVE;
+       if (retval == 0)
+               port->flags |= ASYNC_NORMAL_ACTIVE;
+       spin_unlock_irqrestore(&port->lock, flags);
        return 0;
 }
 
@@ -1015,7 +1013,7 @@ static void rc_close(struct tty_struct *tty, struct file *filp)
        if (!port || rc_paranoia_check(port, tty->name, "close"))
                return;
 
-       spin_lock_irqsave(&riscom_lock, flags);
+       spin_lock_irqsave(&port->port.lock, flags);
 
        if (tty_hung_up_p(filp))
                goto out;
@@ -1041,6 +1039,7 @@ static void rc_close(struct tty_struct *tty, struct file *filp)
         * the line discipline to only process XON/XOFF characters.
         */
        tty->closing = 1;
+       spin_unlock_irqrestore(&port->port.lock, flags);
        if (port->port.closing_wait != ASYNC_CLOSING_WAIT_NONE)
                tty_wait_until_sent(tty, port->port.closing_wait);
        /*
@@ -1049,6 +1048,8 @@ static void rc_close(struct tty_struct *tty, struct file *filp)
         * interrupt driver to stop checking the data ready bit in the
         * line status register.
         */
+
+       spin_lock_irqsave(&riscom_lock, flags);
        port->IER &= ~IER_RXD;
        if (port->port.flags & ASYNC_INITIALIZED) {
                port->IER &= ~IER_TXRDY;
@@ -1062,21 +1063,27 @@ static void rc_close(struct tty_struct *tty, struct file *filp)
                 */
                timeout = jiffies + HZ;
                while (port->IER & IER_TXEMPTY) {
+                       spin_unlock_irqrestore(&riscom_lock, flags);
                        msleep_interruptible(jiffies_to_msecs(port->timeout));
+                       spin_lock_irqsave(&riscom_lock, flags);
                        if (time_after(jiffies, timeout))
                                break;
                }
        }
        rc_shutdown_port(tty, bp, port);
        rc_flush_buffer(tty);
+       spin_unlock_irqrestore(&riscom_lock, flags);
        tty_ldisc_flush(tty);
 
+       spin_lock_irqsave(&port->port.lock, flags);
        tty->closing = 0;
        port->port.tty = NULL;
        if (port->port.blocked_open) {
+               spin_unlock_irqrestore(&port->port.lock, flags);
                if (port->port.close_delay)
                        msleep_interruptible(jiffies_to_msecs(port->port.close_delay));
                wake_up_interruptible(&port->port.open_wait);
+               spin_lock_irqsave(&port->port.lock, flags);
        }
        port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
        wake_up_interruptible(&port->port.close_wait);
@@ -1465,6 +1472,7 @@ static void rc_hangup(struct tty_struct *tty)
 {
        struct riscom_port *port = (struct riscom_port *)tty->driver_data;
        struct riscom_board *bp;
+       unsigned long flags;
 
        if (rc_paranoia_check(port, tty->name, "rc_hangup"))
                return;
@@ -1472,10 +1480,12 @@ static void rc_hangup(struct tty_struct *tty)
        bp = port_Board(port);
 
        rc_shutdown_port(tty, bp, port);
+       spin_lock_irqsave(&port->port.lock, flags);
        port->port.count = 0;
        port->port.flags &= ~ASYNC_NORMAL_ACTIVE;
        port->port.tty = NULL;
        wake_up_interruptible(&port->port.open_wait);
+       spin_unlock_irqrestore(&port->port.lock, flags);
 }
 
 static void rc_set_termios(struct tty_struct *tty,