[PATCH V13 4/6] mdev: introduce mediated virtio bus

[Jason Gunthorpe]

On Mon, Nov 18, 2019 at 06:59:21PM +0800, Jason Wang wrote:
> +struct bus_type mdev_virtio_bus_type;
> +
> +struct mdev_virtio_device {
> +	struct mdev_device mdev;
> +	const struct mdev_virtio_ops *ops;
> +	u16 class_id;
> +};

This seems to share nothing with mdev (ie mdev-vfio), why is it on the
same bus?

We went over this recently with Greg and he seemed pretty clear on
this..

> +struct mdev_virtio_ops {
> +	/* Virtqueue ops */
> +	int (*set_vq_address)(struct mdev_device *mdev,
> +			      u16 idx, u64 desc_area, u64 driver_area,
> +			      u64 device_area);
> +	void (*set_vq_num)(struct mdev_device *mdev, u16 idx, u32 num);
> +	void (*kick_vq)(struct mdev_device *mdev, u16 idx);
> +	void (*set_vq_cb)(struct mdev_device *mdev, u16 idx,
> +			  struct virtio_mdev_callback *cb);
> +	void (*set_vq_ready)(struct mdev_device *mdev, u16 idx, bool ready);
> +	bool (*get_vq_ready)(struct mdev_device *mdev, u16 idx);
> +	int (*set_vq_state)(struct mdev_device *mdev, u16 idx, u64 state);
> +	u64 (*get_vq_state)(struct mdev_device *mdev, u16 idx);
> +
> +	/* Device ops */
> +	u16 (*get_vq_align)(struct mdev_device *mdev);
> +	u64 (*get_features)(struct mdev_device *mdev);
> +	int (*set_features)(struct mdev_device *mdev, u64 features);
> +	void (*set_config_cb)(struct mdev_device *mdev,
> +			      struct virtio_mdev_callback *cb);
> +	u16 (*get_vq_num_max)(struct mdev_device *mdev);
> +	u32 (*get_device_id)(struct mdev_device *mdev);
> +	u32 (*get_vendor_id)(struct mdev_device *mdev);
> +	u8 (*get_status)(struct mdev_device *mdev);
> +	void (*set_status)(struct mdev_device *mdev, u8 status);
> +	void (*get_config)(struct mdev_device *mdev, unsigned int offset,
> +			   void *buf, unsigned int len);
> +	void (*set_config)(struct mdev_device *mdev, unsigned int offset,
> +			   const void *buf, unsigned int len);
> +	u32 (*get_generation)(struct mdev_device *mdev);
> +};

Why aren't all of these 'struct mdev_device_virtio *' ?

Jason