Generic dma-coherent: fix DMA_MEMORY_EXCLUSIVE

Don't rewrite successfull allocation return values
in case the memory was marked with DMA_MEMORY_EXCLUSIVE.
Signed-off-by: NDmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/dma-coherent.c

@@ -105,8 +105,7 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
 			*dma_handle = mem->device_base + (page << PAGE_SHIFT);
 			*ret = mem->virt_base + (page << PAGE_SHIFT);
 			memset(*ret, 0, size);
-		}
-		if (mem->flags & DMA_MEMORY_EXCLUSIVE)
+		} else if (mem->flags & DMA_MEMORY_EXCLUSIVE)
 			*ret = NULL;
 	}
 	return (mem != NULL);