s390/cio: get rid of static console device

Remove the static console ccw device (and friends) and use dynamic
allocation for these structures. With this change the console
device is treated (mostly) like any other ccw device and we can
remove some special cases.
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/device.c

@@ -1087,19 +1087,12 @@ static int io_subchannel_probe(struct subchannel *sch)
 		dev_set_uevent_suppress(&sch->dev, 0);
 		kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 		cdev = sch_get_cdev(sch);
-		cdev->dev.groups = ccwdev_attr_groups;
-		device_initialize(&cdev->dev);
-		cdev->private->flags.initialized = 1;
-		ccw_device_register(cdev);
-		/*
-		 * Check if the device is already online. If it is
-		 * the reference count needs to be corrected since we
-		 * didn't obtain a reference in ccw_device_set_online.
-		 */
-		if (cdev->private->state != DEV_STATE_NOT_OPER &&
-		    cdev->private->state != DEV_STATE_OFFLINE &&
-		    cdev->private->state != DEV_STATE_BOXED)
-			get_device(&cdev->dev);
+		rc = ccw_device_register(cdev);
+		if (rc) {
+			/* Release online reference. */
+			put_device(&cdev->dev);
+			goto out_schedule;
+		}
 		return 0;
 	}
 	io_subchannel_init_fields(sch);
@@ -1581,10 +1574,6 @@ static int io_subchannel_sch_event(struct subchannel *sch, int process)
 }
 
 #ifdef CONFIG_CCW_CONSOLE
-static struct ccw_device console_cdev;
-static struct ccw_device_private console_private;
-static int console_cdev_in_use;
-
 static int ccw_device_console_enable(struct ccw_device *cdev,
 				     struct subchannel *sch)
 {
@@ -1595,8 +1584,6 @@ static int ccw_device_console_enable(struct ccw_device *cdev,
 	if (rc)
 		return rc;
 	sch->driver = &io_subchannel_driver;
-	/* Initialize the ccw_device structure. */
-	cdev->dev.parent= &sch->dev;
 	sch_set_cdev(sch, cdev);
 	io_subchannel_recog(cdev, sch);
 	/* Now wait for the async. recognition to come to an end. */
@@ -1604,58 +1591,58 @@ static int ccw_device_console_enable(struct ccw_device *cdev,
 	while (!dev_fsm_final_state(cdev))
 		ccw_device_wait_idle(cdev);
 
-	rc = -EIO;
-	if (cdev->private->state != DEV_STATE_OFFLINE)
+	/* Hold on to an extra reference while device is online. */
+	get_device(&cdev->dev);
+	rc = ccw_device_online(cdev);
+	if (rc)
 		goto out_unlock;
-	ccw_device_online(cdev);
+
 	while (!dev_fsm_final_state(cdev))
 		ccw_device_wait_idle(cdev);
 
-	if (cdev->private->state != DEV_STATE_ONLINE)
-		goto out_unlock;
-	rc = 0;
+	if (cdev->private->state == DEV_STATE_ONLINE)
+		cdev->online = 1;
+	else
+		rc = -EIO;
 out_unlock:
 	spin_unlock_irq(cdev->ccwlock);
+	if (rc) /* Give up online reference since onlining failed. */
+		put_device(&cdev->dev);
 	return rc;
 }
 
-struct ccw_device *
-ccw_device_probe_console(void)
+struct ccw_device *ccw_device_probe_console(void)
 {
 	struct io_subchannel_private *io_priv;
+	struct ccw_device *cdev;
 	struct subchannel *sch;
 	int ret;
 
-	if (xchg(&console_cdev_in_use, 1) != 0)
-		return ERR_PTR(-EBUSY);
 	sch = cio_probe_console();
-	if (IS_ERR(sch)) {
-		console_cdev_in_use = 0;
-		return (void *) sch;
-	}
-	memset(&console_cdev, 0, sizeof(struct ccw_device));
-	memset(&console_private, 0, sizeof(struct ccw_device_private));
-	console_cdev.private = &console_private;
-	console_private.cdev = &console_cdev;
-	console_private.int_class = IRQIO_CIO;
+	if (IS_ERR(sch))
+		return ERR_CAST(sch);
 
 	io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
 	if (!io_priv) {
 		put_device(&sch->dev);
 		return ERR_PTR(-ENOMEM);
 	}
+	cdev = io_subchannel_create_ccwdev(sch);
+	if (IS_ERR(cdev)) {
+		put_device(&sch->dev);
+		kfree(io_priv);
+		return cdev;
+	}
 	set_io_private(sch, io_priv);
-
-	ret = ccw_device_console_enable(&console_cdev, sch);
+	ret = ccw_device_console_enable(cdev, sch);
 	if (ret) {
-		console_cdev_in_use = 0;
 		set_io_private(sch, NULL);
 		put_device(&sch->dev);
+		put_device(&cdev->dev);
 		kfree(io_priv);
 		return ERR_PTR(ret);
 	}
-	console_cdev.online = 1;
-	return &console_cdev;
+	return cdev;
 }
 
 /**