Re: [PATCH v4] drm/syncobj: Extend EXPORT_SYNC_FILE for timeline syncobjs

[Dmitry Osipenko]

On 3/28/25 00:36, Rob Clark wrote:
...
>  static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
> -					      int fd, int handle)
> +					      int fd, int handle, u64 point)
>  {
>  	struct dma_fence *fence = sync_file_get_fence(fd);
>  	struct drm_syncobj *syncobj;
> @@ -755,14 +755,18 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
>  		return -ENOENT;
>  	}
>  
> -	drm_syncobj_replace_fence(syncobj, fence);
> +	if (point) {
> +		drm_syncobj_add_point(syncobj, dma_fence_chain_alloc(), fence, point);

Nit: check dma_fence_chain_alloc() for ENOMEM

> +	} else {
> +		drm_syncobj_replace_fence(syncobj, fence);
> +	}

Nit: checkpath should complain about the unnecessary braces

>  	dma_fence_put(fence);
>  	drm_syncobj_put(syncobj);
>  	return 0;
>  }
>  
>  static int drm_syncobj_export_sync_file(struct drm_file *file_private,
> -					int handle, int *p_fd)
> +					int handle, u64 point, int *p_fd)
>  {
>  	int ret;
>  	struct dma_fence *fence;
> @@ -772,7 +776,7 @@ static int drm_syncobj_export_sync_file(struct drm_file *file_private,
>  	if (fd < 0)
>  		return fd;
>  
> -	ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence);
> +	ret = drm_syncobj_find_fence(file_private, handle, point, 0, &fence);
>  	if (ret)
>  		goto err_put_fd;
>  
> @@ -869,6 +873,9 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
>  				   struct drm_file *file_private)
>  {
>  	struct drm_syncobj_handle *args = data;
> +	unsigned valid_flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_TIMELINE |
> +			       DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE;
> +	u64 point = 0;
>  
>  	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
>  		return -EOPNOTSUPP;
> @@ -876,13 +883,18 @@ drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
>  	if (args->pad)
>  		return -EINVAL;
>  
> -	if (args->flags != 0 &&
> -	    args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
> +	if (args->flags != 0 && (args->flags & ~valid_flags))
>  		return -EINVAL;

Nit: args->flags!=0 not needed as (0 & ~valid_flags) is always false,
same for import

...


-- 
Best regards,
Dmitry