On Fri, Jun 30, 2023 at 8:36 AM Shannon Nelson <shannon.nelson@xxxxxxx> wrote:
>
> Our driver sets a mac if the HW is 00:..:00 so we need to be sure to
> advertise VIRTIO_NET_F_MAC even if the HW doesn't. We also need to be
> sure that virtio_net sees the VIRTIO_NET_F_MAC and doesn't rewrite the
> mac address that a user may have set with the vdpa utility.
>
> After reading the hw_feature bits, add the VIRTIO_NET_F_MAC to the driver's
> supported_features and use that for reporting what is available. If the
> HW is not advertising it, be sure to strip the VIRTIO_NET_F_MAC before
> finishing the feature negotiation. If the user specifies a device_features
> bitpattern in the vdpa utility without the VIRTIO_NET_F_MAC set, then
> don't set the mac.
>
> Fixes: 151cc834f3dd ("pds_vdpa: add support for vdpa and vdpamgmt interfaces")
> Signed-off-by: Shannon Nelson <shannon.nelson@xxxxxxx>
> Reviewed-by: Brett Creeley <brett.creeley@xxxxxxx>
> ---
> drivers/vdpa/pds/vdpa_dev.c | 25 +++++++++++++++++++------
> 1 file changed, 19 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/vdpa/pds/vdpa_dev.c b/drivers/vdpa/pds/vdpa_dev.c
> index e2e99bb0be2b..5e761d625ef3 100644
> --- a/drivers/vdpa/pds/vdpa_dev.c
> +++ b/drivers/vdpa/pds/vdpa_dev.c
> @@ -316,6 +316,7 @@ static int pds_vdpa_set_driver_features(struct vdpa_device *vdpa_dev, u64 featur
> {
> struct pds_vdpa_device *pdsv = vdpa_to_pdsv(vdpa_dev);
> struct device *dev = &pdsv->vdpa_dev.dev;
> + u64 requested_features;
> u64 driver_features;
> u64 nego_features;
> u64 missing;
> @@ -325,18 +326,24 @@ static int pds_vdpa_set_driver_features(struct vdpa_device *vdpa_dev, u64 featur
> return -EOPNOTSUPP;
> }
>
> + /* save original request for debugfs */
> pdsv->req_features = features;
> + requested_features = features;
> +
> + /* if we're faking the F_MAC, strip it from features to be negotiated */
> + driver_features = pds_vdpa_get_driver_features(vdpa_dev);
> + if (!(driver_features & BIT_ULL(VIRTIO_NET_F_MAC)))
> + requested_features &= ~BIT_ULL(VIRTIO_NET_F_MAC);
I'm not sure I understand here, assuming we are doing feature
negotiation here. In this case driver_features we read should be zero?
Or did you actually mean device_features here?
Thanks
>
> /* Check for valid feature bits */
> - nego_features = features & le64_to_cpu(pdsv->vdpa_aux->ident.hw_features);
> - missing = pdsv->req_features & ~nego_features;
> + nego_features = requested_features & le64_to_cpu(pdsv->vdpa_aux->ident.hw_features);
> + missing = requested_features & ~nego_features;
> if (missing) {
> dev_err(dev, "Can't support all requested features in %#llx, missing %#llx features\n",
> pdsv->req_features, missing);
> return -EOPNOTSUPP;
> }
>
> - driver_features = pds_vdpa_get_driver_features(vdpa_dev);
> dev_dbg(dev, "%s: %#llx => %#llx\n",
> __func__, driver_features, nego_features);
>
> @@ -564,7 +571,7 @@ static int pds_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
>
> if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
> u64 unsupp_features =
> - add_config->device_features & ~mgmt->supported_features;
> + add_config->device_features & ~pdsv->supported_features;
>
> if (unsupp_features) {
> dev_err(dev, "Unsupported features: %#llx\n", unsupp_features);
> @@ -615,7 +622,8 @@ static int pds_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
> }
>
> /* Set a mac, either from the user config if provided
> - * or set a random mac if default is 00:..:00
> + * or use the device's mac if not 00:..:00
> + * or set a random mac
> */
> if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADDR)) {
> ether_addr_copy(pdsv->mac, add_config->net.mac);
> @@ -624,7 +632,8 @@ static int pds_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
>
> vc = pdsv->vdpa_aux->vd_mdev.device;
> memcpy_fromio(pdsv->mac, vc->mac, sizeof(pdsv->mac));
> - if (is_zero_ether_addr(pdsv->mac)) {
> + if (is_zero_ether_addr(pdsv->mac) &&
> + (pdsv->supported_features & BIT_ULL(VIRTIO_NET_F_MAC))) {
> eth_random_addr(pdsv->mac);
> dev_info(dev, "setting random mac %pM\n", pdsv->mac);
> }
> @@ -752,6 +761,10 @@ int pds_vdpa_get_mgmt_info(struct pds_vdpa_aux *vdpa_aux)
> mgmt->id_table = pds_vdpa_id_table;
> mgmt->device = dev;
> mgmt->supported_features = le64_to_cpu(vdpa_aux->ident.hw_features);
> +
> + /* advertise F_MAC even if the device doesn't */
> + mgmt->supported_features |= BIT_ULL(VIRTIO_NET_F_MAC);
> +
> mgmt->config_attr_mask = BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADDR);
> mgmt->config_attr_mask |= BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP);
> mgmt->config_attr_mask |= BIT_ULL(VDPA_ATTR_DEV_FEATURES);
> --
> 2.17.1
>
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
