Commit 79b95a45 authored by Linus Torvalds's avatar Linus Torvalds
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Revert "x86-64: Avoid unnecessary double bouncing for swiotlb" 



Commit id 6142891a

Andi Kleen reports that it seems to break things for some people,
and since it's purely a small optimization, revert it for now.

Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 72ab373a

include/asm-x86_64/pci.h

+3 −3
Original line number Diff line number Diff line
@@ -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 x86-64 it mostly equals, but we set it to zero to tell some subsystems

 * that an hard or soft IOMMU is available.

 * On AMD64 it mostly equals, but we set it to zero to tell some subsystems

 * that an IOMMU is available.

 */

#define PCI_DMA_BUS_IS_PHYS 0

#define PCI_DMA_BUS_IS_PHYS	(no_iommu ? 1 : 0)



/*

 * x86-64 always supports DAC, but sometimes it is useful to force