drm/amdgpu: deal with foreign fences in amdgpu_sync

This also requires some error handling from the callers of that function.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
index bc0fac6..2722815 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
@@ -167,7 +167,11 @@
 		/* grab a vm id if necessary */
 		struct amdgpu_fence *vm_id_fence = NULL;
 		vm_id_fence = amdgpu_vm_grab_id(ibs->ring, ibs->vm);
-		amdgpu_sync_fence(&ibs->sync, vm_id_fence);
+		r = amdgpu_sync_fence(adev, &ibs->sync, &vm_id_fence->base);
+		if (r) {
+			amdgpu_ring_unlock_undo(ring);
+			return r;
+		}
 	}
 
 	r = amdgpu_sync_rings(&ibs->sync, ring);