virtio: console: Accept console size along with resize control message

The VIRTIO_CONSOLE_RESIZE control message sent to us by the host now
contains the new {rows, cols} values for the console. This ensures each
console port gets its own size, and we don't depend on the config-space
rows and cols values at all now.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
CC: Christian Borntraeger <borntraeger@de.ibm.com>
CC: linuxppc-dev@ozlabs.org
CC: Kusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

drivers/char/virtio_console.c

@@ -1194,12 +1194,23 @@ static void handle_control_message(struct ports_device *portdev,
 		 * have to notify the host first.
 		 */
 		break;
-	case VIRTIO_CONSOLE_RESIZE:
+	case VIRTIO_CONSOLE_RESIZE: {
+		struct {
+			__u16 rows;
+			__u16 cols;
+		} size;
+
 		if (!is_console_port(port))
 			break;
+
+		memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
+		       sizeof(size));
+		set_console_size(port, size.rows, size.cols);
+
 		port->cons.hvc->irq_requested = 1;
 		resize_console(port);
 		break;
+	}
 	case VIRTIO_CONSOLE_PORT_OPEN:
 		port->host_connected = cpkt->value;
 		wake_up_interruptible(&port->waitqueue);