drm/amdgpu: add shadow bo support V2

shadow bo is the shadow of a bo, which is always in GTT,
which can be used to backup the original bo.
V2:
reference shadow parent, shadow bo will be freed by who allocted him.

Signed-off-by: Chunming Zhou <David1.Zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index c54f5b962b80..26f6028bb72b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -505,6 +505,7 @@ struct amdgpu_bo {
         struct amdgpu_device            *adev;
         struct drm_gem_object           gem_base;
         struct amdgpu_bo                *parent;
+        struct amdgpu_bo                *shadow;
 
         struct ttm_bo_kmap_obj          dma_buf_vmap;
         struct amdgpu_mn                *mn;