[PATCH] drm/vgem: Convert to a struct drm_device subclass

[Laura Abbott]

On 05/08/2017 06:22 AM, Chris Wilson wrote:
> With Laura's introduction of the fake platform device for importing
> dmabuf, we add a second static that is logically tied to the vgem_device.
> Convert vgem over to using the struct drm_device subclassing, so that
> the platform device is stored inside its owner.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Laura Abbott <labbott at redhat.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
>   drivers/gpu/drm/vgem/vgem_drv.c | 63 +++++++++++++++++++++++++++--------------
>   1 file changed, 41 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c
> index c9381d457a03..4b23ba049632 100644
> --- a/drivers/gpu/drm/vgem/vgem_drv.c
> +++ b/drivers/gpu/drm/vgem/vgem_drv.c
> @@ -42,7 +42,10 @@
>   #define DRIVER_MAJOR	1
>   #define DRIVER_MINOR	0
>   
> -static struct platform_device *vgem_platform;
> +static struct vgem_device {
> +	struct drm_device drm;
> +	struct platform_device *platform;
> +} *vgem_device;
>   
>   static void vgem_gem_free_object(struct drm_gem_object *obj)
>   {
> @@ -307,7 +310,9 @@ static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj)
>   static struct drm_gem_object* vgem_prime_import(struct drm_device *dev,
>   						struct dma_buf *dma_buf)
>   {
> -	return drm_gem_prime_import_dev(dev, dma_buf, &vgem_platform->dev);
> +	struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
> +
> +	return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev);
>   }
>   
>   static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,
> @@ -377,8 +382,19 @@ static int vgem_prime_mmap(struct drm_gem_object *obj,
>   	return 0;
>   }
>   
> +static void vgem_release(struct drm_device *dev)
> +{
> +	struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
> +
> +	platform_device_unregister(vgem->platform);
> +	drm_dev_fini(&vgem->drm);
> +
> +	kfree(vgem);
> +}
> +
>   static struct drm_driver vgem_driver = {
>   	.driver_features		= DRIVER_GEM | DRIVER_PRIME,
> +	.release			= vgem_release,
>   	.open				= vgem_open,
>   	.postclose			= vgem_postclose,
>   	.gem_free_object_unlocked	= vgem_gem_free_object,
> @@ -408,45 +424,48 @@ static struct drm_driver vgem_driver = {
>   	.minor	= DRIVER_MINOR,
>   };
>   
> -static struct drm_device *vgem_device;
> -
>   static int __init vgem_init(void)
>   {
>   	int ret;
>   
> -	vgem_device = drm_dev_alloc(&vgem_driver, NULL);
> -	if (IS_ERR(vgem_device))
> -		return PTR_ERR(vgem_device);
> +	vgem_device = kzalloc(sizeof(*vgem_device), GFP_KERNEL);
> +	if (!vgem_device)
> +		return -ENOMEM;
>   
> -	vgem_platform = platform_device_register_simple("vgem",
> -					-1, NULL, 0);
> +	ret = drm_dev_init(&vgem_device->drm, &vgem_driver, NULL);
> +	if (ret)
> +		goto out_free;
>   
> -	if (!vgem_platform) {
> +	vgem_device->platform =
> +		platform_device_register_simple("vgem", -1, NULL, 0);
> +	if (!vgem_device->platform) {
>   		ret = -ENODEV;
> -		goto out;
> +		goto out_fini;
>   	}
>   
> -	dma_coerce_mask_and_coherent(&vgem_platform->dev,
> -					DMA_BIT_MASK(64));
> +	dma_coerce_mask_and_coherent(&vgem_device->platform->dev,
> +				     DMA_BIT_MASK(64));
>   
> -	ret  = drm_dev_register(vgem_device, 0);
> +	/* Final step: expose the device/driver to userspace */
> +	ret  = drm_dev_register(&vgem_device->drm, 0);
>   	if (ret)
> -		goto out_unref;
> +		goto out_unregister;
>   
>   	return 0;
>   
> -out_unref:
> -	platform_device_unregister(vgem_platform);
> -out:
> -	drm_dev_unref(vgem_device);
> +out_unregister:
> +	platform_device_unregister(vgem_device->platform);
> +out_fini:
> +	drm_dev_fini(&vgem_device->drm > +out_free:
> +	kfree(vgem_device);
>   	return ret;
>   }
>   
>   static void __exit vgem_exit(void)
>   {
> -	platform_device_unregister(vgem_platform);
> -	drm_dev_unregister(vgem_device);
> -	drm_dev_unref(vgem_device);
> +	drm_dev_unregister(&vgem_device->drm);
> +	drm_dev_unref(&vgem_device->drm);
>   }
>   
>   module_init(vgem_init);
> 

Reviewed-by: Laura Abbott <labbott at redhat.com>