ctcm: suspend has to wait for outstanding I/O

State transition to DEV_STATE_STOPPED indicates all outstanding I/O has
finished. Add wait queue to wait for this state.

Signed-off-by: Frank Blaschka <[e-mail]>
Signed-off-by: Ursula Braun <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/s390/net/ctcm_main.c

···
 		return 0;
 	netif_device_detach(priv->channel[READ]->netdev);
 	ctcm_close(priv->channel[READ]->netdev);
+	if (!wait_event_timeout(priv->fsm->wait_q,
+	    fsm_getstate(priv->fsm) == DEV_STATE_STOPPED, CTCM_TIME_5_SEC)) {
+		netif_device_attach(priv->channel[READ]->netdev);
+		return -EBUSY;
+	}
 	ccw_device_set_offline(gdev->cdev[1]);
 	ccw_device_set_offline(gdev->cdev[0]);
 	return 0;

drivers/s390/net/fsm.c

···
 		return NULL;
 	}
 	strlcpy(this->name, name, sizeof(this->name));
+	init_waitqueue_head(&this->wait_q);
 
 	f = kzalloc(sizeof(fsm), order);
 	if (f == NULL) {

drivers/s390/net/fsm.h

···
 	char name[16];
 	void *userdata;
 	int userint;
+	wait_queue_head_t wait_q;
 #if FSM_DEBUG_HISTORY
 	int         history_index;
 	int         history_size;
···
 	printk(KERN_DEBUG "fsm(%s): New state %s\n", fi->name,
 		fi->f->state_names[newstate]);
 #endif
+	wake_up(&fi->wait_q);
 }
 
 /**