tty: Replace ASYNC_SUSPENDED bit and update atomically

Replace ASYNC_SUSPENDED bit in the tty_port::flags field with
TTY_PORT_SUSPENDED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_suspended() and tty_port_suspended() to abstract
atomic bit ops.

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

diff --git a/drivers/s390/char/con3215.c b/drivers/s390/char/con3215.c
index e7e078b..114fe28 100644 (file)
--- a/drivers/s390/char/con3215.c
+++ b/drivers/s390/char/con3215.c
@@ -289,7 +289,7 @@ static void raw3215_timeout(unsigned long __data)
 
        spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
        raw->flags &= ~RAW3215_TIMER_RUNS;
-       if (!(raw->port.flags & ASYNC_SUSPENDED)) {
+       if (!tty_port_suspended(&raw->port)) {
                raw3215_mk_write_req(raw);
                raw3215_start_io(raw);
                if ((raw->queued_read || raw->queued_write) &&
@@ -312,7 +312,7 @@ static void raw3215_timeout(unsigned long __data)
 static inline void raw3215_try_io(struct raw3215_info *raw)
 {
        if (!(raw->port.flags & ASYNC_INITIALIZED) ||
-                       (raw->port.flags & ASYNC_SUSPENDED))
+           tty_port_suspended(&raw->port))
                return;
        if (raw->queued_read != NULL)
                raw3215_start_io(raw);
@@ -494,7 +494,7 @@ static void raw3215_make_room(struct raw3215_info *raw, unsigned int length)
                /* While console is frozen for suspend we have no other
                 * choice but to drop message from the buffer to make
                 * room for even more messages. */
-               if (raw->port.flags & ASYNC_SUSPENDED) {
+               if (tty_port_suspended(&raw->port)) {
                        raw3215_drop_line(raw);
                        continue;
                }
@@ -773,7 +773,7 @@ static int raw3215_pm_stop(struct ccw_device *cdev)
        raw = dev_get_drvdata(&cdev->dev);
        spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
        raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
-       raw->port.flags |= ASYNC_SUSPENDED;
+       tty_port_set_suspended(&raw->port, 1);
        spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
        return 0;
 }
@@ -786,7 +786,7 @@ static int raw3215_pm_start(struct ccw_device *cdev)
        /* Allow I/O again and flush output buffer. */
        raw = dev_get_drvdata(&cdev->dev);
        spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
-       raw->port.flags &= ~ASYNC_SUSPENDED;
+       tty_port_set_suspended(&raw->port, 0);
        raw->flags |= RAW3215_FLUSHING;
        raw3215_try_io(raw);
        raw->flags &= ~RAW3215_FLUSHING;
@@ -859,7 +859,7 @@ static void con3215_flush(void)
        unsigned long flags;
 
        raw = raw3215[0];  /* console 3215 is the first one */
-       if (raw->port.flags & ASYNC_SUSPENDED)
+       if (tty_port_suspended(&raw->port))
                /* The console is still frozen for suspend. */
                if (ccw_device_force_console(raw->cdev))
                        /* Forcing didn't work, no panic message .. */

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 2471380..9336067 100644 (file)
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -249,7 +249,7 @@ static void uart_shutdown(struct tty_struct *tty, struct uart_state *state)
         * a DCD drop (hangup) at just the right time.  Clear suspended bit so
         * we don't try to resume a port that has been shutdown.
         */
-       clear_bit(ASYNCB_SUSPENDED, &port->flags);
+       tty_port_set_suspended(port, 0);
 
        /*
         * Free the transmit buffer page.
@@ -2007,7 +2007,7 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
                const struct uart_ops *ops = uport->ops;
                int tries;
 
-               set_bit(ASYNCB_SUSPENDED, &port->flags);
+               tty_port_set_suspended(port, 1);
                clear_bit(ASYNCB_INITIALIZED, &port->flags);
 
                spin_lock_irq(&uport->lock);
@@ -2088,7 +2088,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
                        console_start(uport->cons);
        }
 
-       if (port->flags & ASYNC_SUSPENDED) {
+       if (tty_port_suspended(port)) {
                const struct uart_ops *ops = uport->ops;
                int ret;
 
@@ -2118,7 +2118,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
                        }
                }
 
-               clear_bit(ASYNCB_SUSPENDED, &port->flags);
+               tty_port_set_suspended(port, 0);
        }
 
        mutex_unlock(&port->mutex);

diff --git a/include/linux/tty.h b/include/linux/tty.h
index 4254dfb..7ac5add 100644 (file)
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -597,6 +597,19 @@ static inline void tty_port_set_check_carrier(struct tty_port *port, bool val)
                clear_bit(TTY_PORT_CHECK_CD, &port->iflags);
 }
 
+static inline bool tty_port_suspended(struct tty_port *port)
+{
+       return test_bit(TTY_PORT_SUSPENDED, &port->iflags);
+}
+
+static inline void tty_port_set_suspended(struct tty_port *port, bool val)
+{
+       if (val)
+               set_bit(TTY_PORT_SUSPENDED, &port->iflags);
+       else
+               clear_bit(TTY_PORT_SUSPENDED, &port->iflags);
+}
+
 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);