drm/prime: Unbreak virtgpu dma-buf export

[ Upstream commit a4ec240f6b ]

virtgpu "vram" GEM objects do not implement obj->get_sg_table().  But
they also don't use drm_gem_map_dma_buf().  In fact they may not even
have guest visible pages.  But it is perfectly fine to export and share
with other virtual devices.

Reported-by: Dominik Behr <dbehr@chromium.org>
Fixes: 207395da5a ("drm/prime: reject DMA-BUF attach when get_sg_table is missing")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Simon Ser <contact@emersion.fr>
Signed-off-by: Simon Ser <contact@emersion.fr>
Link: https://patchwork.freedesktop.org/patch/msgid/20240322214801.319975-1-robdclark@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Rob Clark
2024-03-22 14:48:01 -07:00
committed by Greg Kroah-Hartman
parent 0c16020d2b
commit cc45defb0a

View File

@@ -582,7 +582,12 @@ int drm_gem_map_attach(struct dma_buf *dma_buf,
{ {
struct drm_gem_object *obj = dma_buf->priv; struct drm_gem_object *obj = dma_buf->priv;
if (!obj->funcs->get_sg_table) /*
* drm_gem_map_dma_buf() requires obj->get_sg_table(), but drivers
* that implement their own ->map_dma_buf() do not.
*/
if (dma_buf->ops->map_dma_buf == drm_gem_map_dma_buf &&
!obj->funcs->get_sg_table)
return -ENOSYS; return -ENOSYS;
return drm_gem_pin(obj); return drm_gem_pin(obj);