virtio_console: Use virtio device index to generate port name

Use virtio device index for creating unique device port names.
Current index allocation in virtio is based on a monotonically
increasing variable "index". A better handling of this is to
use device index which is allocated by ida.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 95cae77..2cfd5a0 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -61,9 +61,6 @@
 	/* List of all the devices we're handling */
 	struct list_head portdevs;
 
-	/* Number of devices this driver is handling */
-	unsigned int index;
-
 	/*
 	 * This is used to keep track of the number of hvc consoles
 	 * spawned by this driver.  This number is given as the first
@@ -169,9 +166,6 @@
 	/* Array of per-port IO virtqueues */
 	struct virtqueue **in_vqs, **out_vqs;
 
-	/* Used for numbering devices for sysfs and debugfs */
-	unsigned int drv_index;
-
 	/* Major number for this device.  Ports will be created as minors. */
 	int chr_major;
 };
@@ -1415,7 +1409,7 @@
 	}
 	port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
 				  devt, port, "vport%up%u",
-				  port->portdev->drv_index, id);
+				  port->portdev->vdev->index, id);
 	if (IS_ERR(port->dev)) {
 		err = PTR_ERR(port->dev);
 		dev_err(&port->portdev->vdev->dev,
@@ -1470,7 +1464,7 @@
 		 * inspect a port's state at any time
 		 */
 		sprintf(debugfs_name, "vport%up%u",
-			port->portdev->drv_index, id);
+			port->portdev->vdev->index, id);
 		port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
 							 pdrvdata.debugfs_dir,
 							 port,
@@ -1961,16 +1955,12 @@
 	portdev->vdev = vdev;
 	vdev->priv = portdev;
 
-	spin_lock_irq(&pdrvdata_lock);
-	portdev->drv_index = pdrvdata.index++;
-	spin_unlock_irq(&pdrvdata_lock);
-
 	portdev->chr_major = register_chrdev(0, "virtio-portsdev",
 					     &portdev_fops);
 	if (portdev->chr_major < 0) {
 		dev_err(&vdev->dev,
 			"Error %d registering chrdev for device %u\n",
-			portdev->chr_major, portdev->drv_index);
+			portdev->chr_major, vdev->index);
 		err = portdev->chr_major;
 		goto free;
 	}