drm/amdgpu: Don't move pinned BOs

The purpose of pinning is to prevent a buffer from moving.

Reviewed-by: Christian König <christian.koenig@amd.com>
Tested-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index 151a2d4..56d1458 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -608,6 +608,10 @@
 	if ((offset + size) <= adev->mc.visible_vram_size)
 		return 0;
 
+	/* Can't move a pinned BO to visible VRAM */
+	if (abo->pin_count > 0)
+		return -EINVAL;
+
 	/* hurrah the memory is not visible ! */
 	amdgpu_ttm_placement_from_domain(abo, AMDGPU_GEM_DOMAIN_VRAM);
 	lpfn =	adev->mc.visible_vram_size >> PAGE_SHIFT;