ia64: dma_alloc_coherent always use GFP_DMA

This patch makes dma_alloc_coherent use GFP_DMA at all times. This is
necessary for swiotlb, which requires the callers to set up the gfp
flags properly.

swiotlb_alloc_coherent tries to allocate pages with the gfp flags. If
the allocated memory isn't fit for dev->coherent_dma_mask,
swiotlb_alloc_coherent reserves some of the swiotlb memory area, which
is precious resource. So the callers need to set up the gfp flags
properly.

This patch means that other IA64 IOMMUs' dma_alloc_coherent also use
GFP_DMA. These IOMMUs (e.g. SBA IOMMU) don't need GFP_DMA since they
can map a memory to any address. But IA64's GFP_DMA is large,
generally drivers allocate small memory with dma_alloc_coherent only
at startup. So I chose the simplest way to set up the gfp flags for
swiotlb.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/ia64/include/asm/dma-mapping.h b/arch/ia64/include/asm/dma-mapping.h
index 9f0df9bd46b7f1a772f5a121782a73b70b753af4..06ff1ba21465a38dff682a5b19d0a6a05eab938a 100644 (file)
--- a/arch/ia64/include/asm/dma-mapping.h
+++ b/arch/ia64/include/asm/dma-mapping.h
@@ -8,7 +8,9 @@
 #include <asm/machvec.h>
 #include <linux/scatterlist.h>
 
-#define dma_alloc_coherent     platform_dma_alloc_coherent
+#define dma_alloc_coherent(dev, size, handle, gfp)     \
+       platform_dma_alloc_coherent(dev, size, handle, (gfp) | GFP_DMA)
+
 /* coherent mem. is cheap */
 static inline void *
 dma_alloc_noncoherent(struct device *dev, size_t size, dma_addr_t *dma_handle,