From d3f5f065603705cd4275d57324c49e391f786b5e Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 13 Jan 2015 16:34:58 +0200 Subject: [PATCH] virtio_pci_modern: support devices with no config 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 Signed-off-by: Rusty Russell --- 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 0e54cc88fdf5..68ebc204e3ea 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; -- 2.30.2