ttm_bo_swapout
swapped = ttm_bo_swapout(priv->ttm_dev, &ctx_init, man, GFP_KERNEL,
EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_bo_swapout);
lret = ttm_bo_swapout(bdev, ctx, man, gfp_flags, 1);
s64 ttm_bo_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,