Virtio 1.0 spec lists device config as optional.
Set get/set callbacks to NULL. Drivers can check that
and fail gracefully.
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Tested-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
---
drivers/virtio/virtio_pci_modern.c | 21 +++++++++++++++++++--
1 file changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 0e54cc8..68ebc20 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -422,6 +422,21 @@ static void del_vq(struct virtio_pci_vq_info *info)
free_pages_exact(info->queue, vring_pci_size(info->num));
}
+static const struct virtio_config_ops virtio_pci_config_nodev_ops = {
+ .get = NULL,
+ .set = NULL,
+ .generation = vp_generation,
+ .get_status = vp_get_status,
+ .set_status = vp_set_status,
+ .reset = vp_reset,
+ .find_vqs = vp_modern_find_vqs,
+ .del_vqs = vp_del_vqs,
+ .get_features = vp_get_features,
+ .finalize_features = vp_finalize_features,
+ .bus_name = vp_bus_name,
+ .set_vq_affinity = vp_set_vq_affinity,
+};
+
static const struct virtio_config_ops virtio_pci_config_ops = {
.get = vp_get,
.set = vp_set,
@@ -652,9 +667,11 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
&vp_dev->device_len);
if (!vp_dev->device)
goto err_map_device;
- }
- vp_dev->vdev.config = &virtio_pci_config_ops;
+ vp_dev->vdev.config = &virtio_pci_config_ops;
+ } else {
+ vp_dev->vdev.config = &virtio_pci_config_nodev_ops;
+ }
vp_dev->config_vector = vp_config_vector;
vp_dev->setup_vq = setup_vq;
--
MST
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