[PATCH AUTOSEL 4.20 107/304] drm/v3d: Fix prime imports of buffers from other drivers.

[Sasha Levin]

From: Eric Anholt <eric at anholt.net>

[ Upstream commit 62d1a752874962f072de8a779e960fcd2ab4847b ]

v3d_bo_get_pages() checks this to decide to map the imported buffer
instead of the backing shmem file.  The caller was about to set this
value anyway, and there's no error path in between.  Ideally we
wouldn't even allocate the shmem file for our imports, but that's a
more invasive fix.

Signed-off-by: Eric Anholt <eric at anholt.net>
Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
Link: https://patchwork.freedesktop.org/patch/msgid/20181128230927.10951-3-eric@anholt.net
Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Reviewed-by: Dave Emett <david.emett at broadcom.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/v3d/v3d_bo.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c
index 54d96518a131..a08766d39eab 100644
--- a/drivers/gpu/drm/v3d/v3d_bo.c
+++ b/drivers/gpu/drm/v3d/v3d_bo.c
@@ -293,6 +293,7 @@ v3d_prime_import_sg_table(struct drm_device *dev,
 	bo->resv = attach->dmabuf->resv;
 
 	bo->sgt = sgt;
+	obj->import_attach = attach;
 	v3d_bo_get_pages(bo);
 
 	v3d_mmu_insert_ptes(bo);
-- 
2.19.1