Re: [PATCH V3 2/3] vdpa_sim_net: support feature provisioning

[Stefano Garzarella]

On Tue, Sep 27, 2022 at 03:48:09PM +0800, Jason Wang wrote:
> 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
>
> For example:
>
> # vdpa mgmtdev show
> vdpasim_net:
>  supported_classes net
>  max_supported_vqs 3
>  dev_features MTU MAC CTRL_VQ CTRL_MAC_ADDR ANY_LAYOUT VERSION_1 ACCESS_PLATFORM
>
> 1) provision vDPA device with all features that are supported by the
>   net simulator
>
> # vdpa dev add name dev1 mgmtdev vdpasim_net
> # vdpa dev config show
> dev1: mac 00:00:00:00:00:00 link up link_announce false mtu 1500
>  negotiated_features MTU MAC CTRL_VQ CTRL_MAC_ADDR VERSION_1 ACCESS_PLATFORM
>
> 2) provision vDPA device with a subset of the features
>
> # vdpa dev add name dev1 mgmtdev vdpasim_net device_features 0x300020000
> # vdpa dev config show
> dev1: mac 00:00:00:00:00:00 link up link_announce false mtu 1500
>  negotiated_features CTRL_VQ VERSION_1 ACCESS_PLATFORM
>
> Reviewed-by: Eli Cohen <elic@xxxxxxxxxx>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> ---
> drivers/vdpa/vdpa_sim/vdpa_sim.c     | 12 +++++++++++-
> drivers/vdpa/vdpa_sim/vdpa_sim.h     |  3 ++-
> drivers/vdpa/vdpa_sim/vdpa_sim_blk.c |  2 +-
> drivers/vdpa/vdpa_sim/vdpa_sim_net.c |  5 +++--
> 4 files changed, 17 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index 225b7f5d8be3..b071f0d842fb 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -18,6 +18,7 @@
> #include <linux/vdpa.h>
> #include <linux/vhost_iotlb.h>
> #include <linux/iova.h>
> +#include <uapi/linux/vdpa.h>
>
> #include "vdpa_sim.h"
>
> @@ -245,13 +246,22 @@ static const struct dma_map_ops vdpasim_dma_ops = {
> static const struct vdpa_config_ops vdpasim_config_ops;
> static const struct vdpa_config_ops vdpasim_batch_config_ops;
>
> -struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr)
> +struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr,
> +			       const struct vdpa_dev_set_config *config)
> {
> 	const struct vdpa_config_ops *ops;
> 	struct vdpasim *vdpasim;
> 	struct device *dev;
> 	int i, ret = -ENOMEM;
>
> +	if (config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
> +		if (config->device_features &
> +		    ~dev_attr->supported_features)
> +			return ERR_PTR(-EINVAL);
> +		dev_attr->supported_features =
> +			config->device_features;
> +	}
> +
> 	if (batch_mapping)
> 		ops = &vdpasim_batch_config_ops;
> 	else
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
> index 061986f30911..0e78737dcc16 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
> @@ -71,7 +71,8 @@ struct vdpasim {
> 	spinlock_t iommu_lock;
> };
>
> -struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *attr);
> +struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *attr,
> +			       const struct vdpa_dev_set_config *config);
>
> /* TODO: cross-endian support */
> static inline bool vdpasim_is_little_endian(struct vdpasim *vdpasim)
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> index c8bfea3b7db2..c6db1a1baf76 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> @@ -383,7 +383,7 @@ static int vdpasim_blk_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
> 	dev_attr.work_fn = vdpasim_blk_work;
> 	dev_attr.buffer_size = VDPASIM_BLK_CAPACITY << SECTOR_SHIFT;
>
> -	simdev = vdpasim_create(&dev_attr);
> +	simdev = vdpasim_create(&dev_attr, config);
> 	if (IS_ERR(simdev))
> 		return PTR_ERR(simdev);
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> index 886449e88502..c3cb225ea469 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
> @@ -254,7 +254,7 @@ 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;
>
> -	simdev = vdpasim_create(&dev_attr);
> +	simdev = vdpasim_create(&dev_attr, config);
> 	if (IS_ERR(simdev))
> 		return PTR_ERR(simdev);
>
> @@ -294,7 +294,8 @@ 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

Fine for me:

Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

I'll send a followup to enable VDPA_ATTR_DEV_FEATURES in vdpa_sim_blk 
and test it.

Thanks,
Stefano