This patch implements features provisioning for vdpa_sim_net.

1) validating the provisioned features to be a subset of the parent
   features.
2) clearing the features that is not wanted by the  userspace

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
index 886449e88502..a9ba02be378b 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
@@ -254,6 +254,14 @@ static int vdpasim_net_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	dev_attr.work_fn = vdpasim_net_work;
 	dev_attr.buffer_size = PAGE_SIZE;
 
+	if (config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
+		if (config->device_features &
+		    ~dev_attr.supported_features)
+			return -EINVAL;
+		dev_attr.supported_features &=
+			 config->device_features;
+	}
+
 	simdev = vdpasim_create(&dev_attr);
 	if (IS_ERR(simdev))
 		return PTR_ERR(simdev);
@@ -294,7 +302,8 @@ static struct vdpa_mgmt_dev mgmt_dev = {
 	.id_table = id_table,
 	.ops = &vdpasim_net_mgmtdev_ops,
 	.config_attr_mask = (1 << VDPA_ATTR_DEV_NET_CFG_MACADDR |
-			     1 << VDPA_ATTR_DEV_NET_CFG_MTU),
+			     1 << VDPA_ATTR_DEV_NET_CFG_MTU |
+		             1 << VDPA_ATTR_DEV_FEATURES),
 	.max_supported_vqs = VDPASIM_NET_VQ_NUM,
 	.supported_features = VDPASIM_NET_FEATURES,
 };
-- 
2.25.1

> From: Jason Wang <jasowang@redhat.com>
> Sent: Thursday, 15 September 2022 11:51
> To: mst@redhat.com; jasowang@redhat.com
> Cc: Eli Cohen <elic@nvidia.com>; si-wei.liu@oracle.com; Parav Pandit
> <parav@nvidia.com>; wuzongyong@linux.alibaba.com;
> virtualization@lists.linux-foundation.org; linux-kernel@vger.kernel.org;
> eperezma@redhat.com; lingshan.zhu@intel.com; gdawar@xilinx.com;
> lulu@redhat.com; xieyongji@bytedance.com
> Subject: [PATCH 2/3] vdpa_sim_net: support feature provisioning
> 
> This patch implements features provisioning for vdpa_sim_net.
> 
> 1) validating the provisioned features to be a subset of the parent
>    features.
> 2) clearing the features that is not wanted by the  userspace
> 

Reviewed-by: Eli Cohen <elic@nvidia.com>

> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> index 886449e88502..a9ba02be378b 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> @@ -254,6 +254,14 @@ static int vdpasim_net_dev_add(struct
> vdpa_mgmt_dev *mdev, const char *name,
>  	dev_attr.work_fn = vdpasim_net_work;
>  	dev_attr.buffer_size = PAGE_SIZE;
> 
> +	if (config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
> +		if (config->device_features &
> +		    ~dev_attr.supported_features)
> +			return -EINVAL;
> +		dev_attr.supported_features &=
> +			 config->device_features;
> +	}
> +
>  	simdev = vdpasim_create(&dev_attr);
>  	if (IS_ERR(simdev))
>  		return PTR_ERR(simdev);
> @@ -294,7 +302,8 @@ static struct vdpa_mgmt_dev mgmt_dev = {
>  	.id_table = id_table,
>  	.ops = &vdpasim_net_mgmtdev_ops,
>  	.config_attr_mask = (1 << VDPA_ATTR_DEV_NET_CFG_MACADDR |
> -			     1 << VDPA_ATTR_DEV_NET_CFG_MTU),
> +			     1 << VDPA_ATTR_DEV_NET_CFG_MTU |
> +		             1 << VDPA_ATTR_DEV_FEATURES),
>  	.max_supported_vqs = VDPASIM_NET_VQ_NUM,
>  	.supported_features = VDPASIM_NET_FEATURES,
>  };
> --
> 2.25.1