virtio: enhance id_matching for virtio drivers

This patch allows a virtio driver to use VIRTIO_DEV_ANY_ID for the
device id. This will be used by a test module that can be bound to
any virtio device.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

drivers/virtio/virtio.c

@@ -58,7 +58,7 @@ static struct device_attribute virtio_dev_attrs[] = {
 static inline int virtio_id_match(const struct virtio_device *dev,
 				  const struct virtio_device_id *id)
 {
-	if (id->device != dev->id.device)
+	if (id->device != dev->id.device && id->device != VIRTIO_DEV_ANY_ID)
 		return 0;
 
 	return id->vendor == VIRTIO_DEV_ANY_ID || id->vendor == dev->id.vendor;

scripts/mod/file2alias.c

@@ -641,7 +641,7 @@ static int do_virtio_entry(const char *filename, struct virtio_device_id *id,
 	id->vendor = TO_NATIVE(id->vendor);
 
 	strcpy(alias, "virtio:");
-	ADD(alias, "d", 1, id->device);
+	ADD(alias, "d", id->device != VIRTIO_DEV_ANY_ID, id->device);
 	ADD(alias, "v", id->vendor != VIRTIO_DEV_ANY_ID, id->vendor);
 
 	add_wildcard(alias);