dma-direct: don't retry allocation for no-op GFP_DMA

When an allocation with lower dma_coherent mask fails, dma_direct_alloc() retries the allocation with GFP_DMA. But, this is useless for architectures that hav no ZONE_DMA. Fix it by adding the check of CONFIG_ZONE_DMA before retrying the allocation. Fixes: 95f1839 ("dma-direct: retry allocations using GFP_DMA for small masks") Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Christoph Hellwig <[email protected]>
chewitt · Apr 23, 2018 · 504a918 · 504a918
1 parent 6d08b06
commit 504a918
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
@@ -84,7 +84,8 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
 		__free_pages(page, page_order);
 		page = NULL;
 
-		if (dev->coherent_dma_mask < DMA_BIT_MASK(32) &&
+		if (IS_ENABLED(CONFIG_ZONE_DMA) &&
+		    dev->coherent_dma_mask < DMA_BIT_MASK(32) &&
 		    !(gfp & GFP_DMA)) {
 			gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
 			goto again;