Indicate if need to sync between bo and shadow, where sync to where.
V2:
Rename to backup_shadow
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>
 
 #define AMDGPU_GEM_DOMAIN_MAX          0x3
 
+enum amdgpu_bo_shadow {
+       AMDGPU_BO_SHADOW_TO_NONE = 0,
+       AMDGPU_BO_SHADOW_TO_PARENT,
+       AMDGPU_BO_SHADOW_TO_SHADOW,
+};
+
 struct amdgpu_bo {
        /* Protected by gem.mutex */
        struct list_head                list;
        struct drm_gem_object           gem_base;
        struct amdgpu_bo                *parent;
        struct amdgpu_bo                *shadow;
+       /* indicate if need to sync between bo and shadow */
+       enum amdgpu_bo_shadow           backup_shadow;
 
        struct ttm_bo_kmap_obj          dma_buf_vmap;
        struct amdgpu_mn                *mn;