tty: relock riscom8 using port locks

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 20 insertions, 10 deletions

diff --git a/drivers/char/riscom8.c b/drivers/char/riscom8.c
index 6ad1c2aa2a98..14662d7aa628 100644
--- a/drivers/char/riscom8.c
+++ b/drivers/char/riscom8.c
@@ -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,