[PATCH] arm: fix pci_set_consistent_dma_mask for dmabounce devices

[FUJITA Tomonori]

This fixes the regression of the
6fee48cd330c68332f9712bc968d934a1a84a32a commit.

After the above commit, pci_set_consistent_dma_mask doesn't work for
dmabounce devices. It converts ARM to use the generic implementation
of pci_set_consistent_dma_mask.

The root cause that ARM's CONFIG_DMABOUNCE uses dev->coherent_dma_mask
for the dma mask of a device _AND_ a bus. dev->coherent_dma_mask is
supposed to represent the dma mask of a device.

The proper solution is that device and bus has the own dma mask
respectively (POWERPC does the similar). But the fix must go to stable
trees so this simple (and hacky a bit) patch works better for now.

For further information: http://lkml.org/lkml/2010/8/10/272

Reported-by: Krzysztof Halasa <khc at pm.waw.pl>
Signed-off-by: FUJITA Tomonori <fujita.tomonori at lab.ntt.co.jp>
Tested-by: Krzysztof Halasa <khc at pm.waw.pl>
Cc: stable at kernel.org
---
 arch/arm/mm/dma-mapping.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index c704eed..2a3fc2e 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -77,6 +77,11 @@ static struct page *__dma_alloc_buffer(struct device *dev, size_t size, gfp_t gf
 	if (mask < 0xffffffffULL)
 		gfp |= GFP_DMA;
 
+#ifdef CONFIG_DMABOUNCE
+	if (dev->archdata.dmabounce)
+		gfp |= GFP_DMA;
+#endif
+
 	page = alloc_pages(gfp, order);
 	if (!page)
 		return NULL;
-- 
1.6.5