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x86/PCI: Adjust GFP mask handling for coherent allocations

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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
8965eb1938 and
4a367f3a9d (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 <jbeulich@novell.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
LKML-Reference: <4AF18187020000780001D8AA@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Jan Beulich 2009-11-08 12:12:14 +01:00 committed by Jesse Barnes
parent 761434a318
commit eb647138ac
2 changed files with 9 additions and 7 deletions
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10
arch/x86/include/asm/dma-mapping.h
View File

@ -14,6 +14,12 @@
#include <asm/swiotlb.h>
#include <asm-generic/dma-coherent.h>
#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;

6
arch/x86/kernel/pci-dma.c
View File

@ -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);