From 6142891a0c0209c91aa4a98f725de0d6e2ed4918 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 12 Sep 2005 18:49:24 +0200 Subject: [PATCH] [PATCH] x86-64: Avoid unnecessary double bouncing for swiotlb PCI_DMA_BUS_IS_PHYS has to be zero even when the GART IOMMU is disabled and the swiotlb is used. Otherwise the block layer does unnecessary double bouncing. Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- include/asm-x86_64/pci.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/asm-x86_64/pci.h b/include/asm-x86_64/pci.h index eeb3088a1c..5a82a6762c 100644 --- a/include/asm-x86_64/pci.h +++ b/include/asm-x86_64/pci.h @@ -50,10 +50,10 @@ extern int iommu_setup(char *opt); * address space. The networking and block device layers use * this boolean for bounce buffer decisions * - * On AMD64 it mostly equals, but we set it to zero to tell some subsystems - * that an IOMMU is available. + * On x86-64 it mostly equals, but we set it to zero to tell some subsystems + * that an hard or soft IOMMU is available. */ -#define PCI_DMA_BUS_IS_PHYS (no_iommu ? 1 : 0) +#define PCI_DMA_BUS_IS_PHYS 0 /* * x86-64 always supports DAC, but sometimes it is useful to force -- 2.39.5