Re: [PATCH 07/13] vfio/mdev: remove mdev_parent_dev

[Kirti Wankhede <kwankhede@xxxxxxxxxx>]

On 6/14/2022 10:24 AM, Christoph Hellwig wrote:
> Just open code the dereferences in the only user.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>

Reviewed-by: Kirti Wankhede <kwankhede@xxxxxxxxxx>

> ---
>   Documentation/driver-api/vfio-mediated-device.rst | 3 ---
>   drivers/gpu/drm/i915/gvt/kvmgt.c                  | 2 +-
>   drivers/vfio/mdev/mdev_core.c                     | 6 ------
>   include/linux/mdev.h                              | 1 -
>   4 files changed, 1 insertion(+), 11 deletions(-)
>
> diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
> index 599008bdc1dcb..27247b3bdcb57 100644
> --- a/Documentation/driver-api/vfio-mediated-device.rst
> +++ b/Documentation/driver-api/vfio-mediated-device.rst
> @@ -202,9 +202,6 @@ Directories and files under the sysfs for Each Physical Device
>   
>   	sprintf(buf, "%s-%s", dev_driver_string(parent->dev), group->name);
>   
> -  (or using mdev_parent_dev(mdev) to arrive at the parent device outside
> -  of the core mdev code)
> -
>   * device_api
>   
>     This attribute should show which device API is being created, for example,
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index 1c6b7e8bec4fb..136f9c0df48b9 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -1549,7 +1549,7 @@ static const struct vfio_device_ops intel_vgpu_dev_ops = {
>   
>   static int intel_vgpu_probe(struct mdev_device *mdev)
>   {
> -	struct device *pdev = mdev_parent_dev(mdev);
> +	struct device *pdev = mdev->type->parent->dev;
>   	struct intel_gvt *gvt = kdev_to_i915(pdev)->gvt;
>   	struct intel_vgpu_type *type =
>   		container_of(mdev->type, struct intel_vgpu_type, type);
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index 49a4a26787ce6..479ae5ed6c392 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -23,12 +23,6 @@ static struct class_compat *mdev_bus_compat_class;
>   static LIST_HEAD(mdev_list);
>   static DEFINE_MUTEX(mdev_list_lock);
>   
> -struct device *mdev_parent_dev(struct mdev_device *mdev)
> -{
> -	return mdev->type->parent->dev;
> -}
> -EXPORT_SYMBOL(mdev_parent_dev);
> -
>   /*
>    * Used in mdev_type_attribute sysfs functions to return the parent struct
>    * device
> diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> index dd11c142bf887..83c85a0247f25 100644
> --- a/include/linux/mdev.h
> +++ b/include/linux/mdev.h
> @@ -100,7 +100,6 @@ void mdev_unregister_parent(struct mdev_parent *parent);
>   int mdev_register_driver(struct mdev_driver *drv);
>   void mdev_unregister_driver(struct mdev_driver *drv);
>   
> -struct device *mdev_parent_dev(struct mdev_device *mdev);
>   static inline struct device *mdev_dev(struct mdev_device *mdev)
>   {
>   	return &mdev->dev;