Before the dma ops unification, IA64 always uses GFP_DMA for dma_alloc_coherent like: #define dma_alloc_coherent(dev, size, handle, gfp) \ platform_dma_alloc_coherent(dev, size, handle, (gfp) | GFP_DMA) This GFP_DMA enforcement doesn't make sense for IOMMUs since they can do address translation to give addresses that devices can access to. The IOMMU drivers ignore the zone flag. However, this is still necessary for swiotlb since it can't do address translation. We don't always need to use GFP_DMA for swiotlb. We need GFP_DMA for devices incapable of 64bit DMA. This patch is sorta updated version of: http://marc.info/?l=linux-kernel&m=122638215612705&w=2 Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> Cc: Yasunori Goto <y-goto@xxxxxxxxxxxxxx> --- arch/ia64/kernel/pci-swiotlb.c | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/arch/ia64/kernel/pci-swiotlb.c b/arch/ia64/kernel/pci-swiotlb.c index 717ad4f..573f02c 100644 --- a/arch/ia64/kernel/pci-swiotlb.c +++ b/arch/ia64/kernel/pci-swiotlb.c @@ -13,8 +13,16 @@ int swiotlb __read_mostly; EXPORT_SYMBOL(swiotlb); +static void *ia64_swiotlb_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp) +{ + if (dev->coherent_dma_mask != DMA_64BIT_MASK) + gfp |= GFP_DMA; + return swiotlb_alloc_coherent(dev, size, dma_handle, gfp); +} + struct dma_map_ops swiotlb_dma_ops = { - .alloc_coherent = swiotlb_alloc_coherent, + .alloc_coherent = ia64_swiotlb_alloc_coherent, .free_coherent = swiotlb_free_coherent, .map_page = swiotlb_map_page, .unmap_page = swiotlb_unmap_page, -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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