[S390] cio: disallow online setting of device in transient state

Return -EAGAIN on writes to sysfs online attribute if the corresponding
ccw device is in transient state.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/device.c

@@ -515,7 +515,11 @@ static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 	int force, ret;
 	unsigned long i;
 
-	if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
+	if ((cdev->private->state != DEV_STATE_OFFLINE &&
+	     cdev->private->state != DEV_STATE_ONLINE &&
+	     cdev->private->state != DEV_STATE_BOXED &&
+	     cdev->private->state != DEV_STATE_DISCONNECTED) ||
+	    atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 		return -EAGAIN;
 
 	if (cdev->drv && !try_module_get(cdev->drv->owner)) {