From eb647138acefc897c0eb6eddd5d3650966dfe627 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Sun, 8 Nov 2009 12:12:14 +0100 Subject: [PATCH] x86/PCI: Adjust GFP mask handling for coherent allocations Rather than forcing GFP flags and DMA mask to be inconsistent, GFP flags should be determined even for the fallback device through dma_alloc_coherent_mask()/dma_alloc_coherent_gfp_flags(). This restores 64-bit behavior as it was prior to commits 8965eb19386fdf5ccd0ef8b02593eb8560aa3416 and 4a367f3a9dbf2e7ffcee4702203479809236ee6e (not sure why there are two of them), where GFP_DMA was forced on for 32-bit, but not for 64-bit, with the slight adjustment that afaict even 32-bit doesn't need this without CONFIG_ISA. Signed-off-by: Jan Beulich Acked-by: Takashi Iwai LKML-Reference: <4AF18187020000780001D8AA@vpn.id2.novell.com> Signed-off-by: Ingo Molnar Signed-off-by: Jesse Barnes --- arch/x86/include/asm/dma-mapping.h | 10 +++++++--- arch/x86/kernel/pci-dma.c | 6 ++---- 2 files changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h index 0ee770d23d0e..6a25d5d42836 100644 --- a/arch/x86/include/asm/dma-mapping.h +++ b/arch/x86/include/asm/dma-mapping.h @@ -14,6 +14,12 @@ #include #include +#ifdef CONFIG_ISA +# define ISA_DMA_BIT_MASK DMA_BIT_MASK(24) +#else +# define ISA_DMA_BIT_MASK DMA_BIT_MASK(32) +#endif + extern dma_addr_t bad_dma_address; extern int iommu_merge; extern struct device x86_dma_fallback_dev; @@ -124,10 +130,8 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, if (dma_alloc_from_coherent(dev, size, dma_handle, &memory)) return memory; - if (!dev) { + if (!dev) dev = &x86_dma_fallback_dev; - gfp |= GFP_DMA; - } if (!is_device_dma_capable(dev)) return NULL; diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index b2a71dca5642..a6e804d16c35 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -45,12 +45,10 @@ int iommu_pass_through __read_mostly; dma_addr_t bad_dma_address __read_mostly = 0; EXPORT_SYMBOL(bad_dma_address); -/* Dummy device used for NULL arguments (normally ISA). Better would - be probably a smaller DMA mask, but this is bug-to-bug compatible - to older i386. */ +/* Dummy device used for NULL arguments (normally ISA). */ struct device x86_dma_fallback_dev = { .init_name = "fallback device", - .coherent_dma_mask = DMA_BIT_MASK(32), + .coherent_dma_mask = ISA_DMA_BIT_MASK, .dma_mask = &x86_dma_fallback_dev.coherent_dma_mask, }; EXPORT_SYMBOL(x86_dma_fallback_dev); -- 2.30.2