Re: [PATCH v4 05/13] drm/mgag200: Use drm_gem_shmem_vmap_local() in damage handling

[Daniel Vetter <daniel@ffwll.ch>]

On Fri, Jan 08, 2021 at 10:43:32AM +0100, Thomas Zimmermann wrote:
> Damage handling in mgag200 requires a short-term mapping of the source
> BO. Use drm_gem_shmem_vmap_local().
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> ---
>  drivers/gpu/drm/mgag200/mgag200_mode.c | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
> index 1dfc42170059..a33e28d4c5e9 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
> @@ -1552,22 +1552,32 @@ mgag200_handle_damage(struct mga_device *mdev, struct drm_framebuffer *fb,
>  		      struct drm_rect *clip)
>  {
>  	struct drm_device *dev = &mdev->base;
> +	struct drm_gem_object *obj = fb->obj[0];
>  	struct dma_buf_map map;
>  	void *vmap;
>  	int ret;
>  
> -	ret = drm_gem_shmem_vmap(fb->obj[0], &map);
> +	ret = dma_resv_lock(obj->resv, NULL);
>  	if (drm_WARN_ON(dev, ret))
> -		return; /* BUG: SHMEM BO should always be vmapped */
> +		return;
> +	ret = drm_gem_shmem_vmap_local(obj, &map);
> +	if (drm_WARN_ON(dev, ret))
> +		goto err_dma_resv_unlock; /* BUG: SHMEM BO should always be vmapped */
>  	vmap = map.vaddr; /* TODO: Use mapping abstraction properly */
>  
>  	drm_fb_memcpy_dstclip(mdev->vram, vmap, fb, clip);
>  
> -	drm_gem_shmem_vunmap(fb->obj[0], &map);
> +	drm_gem_shmem_vunmap_local(obj, &map);
> +	dma_resv_unlock(obj->resv);
>  
>  	/* Always scanout image at VRAM offset 0 */
>  	mgag200_set_startadd(mdev, (u32)0);
>  	mgag200_set_offset(mdev, fb);
> +
> +	return;
> +
> +err_dma_resv_unlock:
> +	dma_resv_unlock(obj->resv);
>  }
>  
>  static void
> -- 
> 2.29.2
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch