> On Mon, 10 Nov 2008, Yasunori Goto wrote: > > > Even if a device allows over 4G access and the driver doesn't specify > > GFP_DMA, dma_alloc_coherent() returns under 4G area. > > GFP_DMA can become 0 for configurations that have > !CONFIG_ZONE_DMA. Then all of memory is available. > > The call is subarch specific. So f.e. Altix sn_dma_alloc_coherent does > not set __GFP_DMA. I heard that Altix has IOMMU and __GFP_DMA is not necessary. > If you have an IA64 arch that only support 32bit I/O then __GFP_DMA in > dma_alloc_coherent makes sense. Agree. But our box supports both of 32bit I/O and 64bit I/O without IOMMU. Is it abnormal platform? New interface is necessary for our box like Altix? Bye. -- Yasunori Goto -- 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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