gpu: ion: Only flush buffers in the chunk heap if they were used cached

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/ion/ion_chunk_heap.c

@@ -104,6 +104,7 @@ static void ion_chunk_heap_free(struct ion_buffer *buffer)
 	ion_heap_buffer_zero(buffer);
 
 	for_each_sg(table->sgl, sg, table->nents, i) {
+		if (ion_buffer_cached(buffer))
 			__dma_page_cpu_to_dev(sg_page(sg), 0, sg_dma_len(sg),
 					      DMA_BIDIRECTIONAL);
 		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),