Re: [PATCH 01/10] vDPA: report virtio-block capacity to user space

[Stefano Garzarella <sgarzare@xxxxxxxxxx>]

On Mon, Feb 19, 2024 at 02:55:57AM +0800, Zhu Lingshan wrote:
> This commit allows userspace to query capacity of
> a virtio-block device.
>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
> ---
> drivers/vdpa/vdpa.c       | 35 +++++++++++++++++++++++++++++++++++
> include/linux/vdpa.h      |  1 +
> include/uapi/linux/vdpa.h |  2 ++
> 3 files changed, 38 insertions(+)

Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> index d0695680b282..d5ccb618de2b 100644
> --- a/drivers/vdpa/vdpa.c
> +++ b/drivers/vdpa/vdpa.c
> @@ -944,6 +944,38 @@ static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *ms
> 	return vdpa_dev_net_mq_config_fill(msg, features_device, &config);
> }
>
> +static int
> +vdpa_dev_blk_capacity_config_fill(struct sk_buff *msg,
> +				  const struct virtio_blk_config *config)
> +{
> +	u64 val_u64;
> +
> +	val_u64 = __virtio64_to_cpu(true, config->capacity);
> +
> +	return nla_put_u64_64bit(msg, VDPA_ATTR_DEV_BLK_CFG_CAPACITY,
> +				 val_u64, VDPA_ATTR_PAD);
> +}
> +
> +static int vdpa_dev_blk_config_fill(struct vdpa_device *vdev,
> +				    struct sk_buff *msg)
> +{
> +	struct virtio_blk_config config = {};
> +	u64 features_device;
> +
> +	vdev->config->get_config(vdev, 0, &config, sizeof(config));
> +
> +	features_device = vdev->config->get_device_features(vdev);
> +
> +	if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_FEATURES, features_device,
> +			      VDPA_ATTR_PAD))
> +		return -EMSGSIZE;
> +
> +	if (vdpa_dev_blk_capacity_config_fill(msg, &config))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> static int
> vdpa_dev_config_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq,
> 		     int flags, struct netlink_ext_ack *extack)
> @@ -988,6 +1020,9 @@ vdpa_dev_config_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid,
> 	case VIRTIO_ID_NET:
> 		err = vdpa_dev_net_config_fill(vdev, msg);
> 		break;
> +	case VIRTIO_ID_BLOCK:
> +		err = vdpa_dev_blk_config_fill(vdev, msg);
> +		break;
> 	default:
> 		err = -EOPNOTSUPP;
> 		break;
> diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> index db15ac07f8a6..a184aa6538cb 100644
> --- a/include/linux/vdpa.h
> +++ b/include/linux/vdpa.h
> @@ -7,6 +7,7 @@
> #include <linux/interrupt.h>
> #include <linux/vhost_iotlb.h>
> #include <linux/virtio_net.h>
> +#include <linux/virtio_blk.h>
> #include <linux/if_ether.h>
>
> /**
> diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h
> index 54b649ab0f22..1bf69226cb96 100644
> --- a/include/uapi/linux/vdpa.h
> +++ b/include/uapi/linux/vdpa.h
> @@ -56,6 +56,8 @@ enum vdpa_attr {
> 	/* virtio features that are provisioned to the vDPA device */
> 	VDPA_ATTR_DEV_FEATURES,                 /* u64 */
>
> +	VDPA_ATTR_DEV_BLK_CFG_CAPACITY,		/* u64 */
> +
> 	/* new attributes must be added above here */
> 	VDPA_ATTR_MAX,
> };
> --
> 2.39.3