xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

dma-mapping: add an arch_dma_supported hook

Browse Source 
To implement the x86 forbid_dac and iommu_sac_force we want an arch hook
so that it can apply the global options across all dma_map_ops
implementations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Christoph Hellwig
2017-12-23 11:01:41 +01:00
parent 57bf5a8963
commit cea9d03c82
3 changed files with 26 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
arch/x86/kernel/pci-dma.c
View File

@@ -215,7 +215,7 @@ static __init int iommu_setup(char *p)
}
early_param("iommu", iommu_setup);
int x86_dma_supported(struct device *dev, u64 mask)
int arch_dma_supported(struct device *dev, u64 mask)
{
#ifdef CONFIG_PCI
if (mask > 0xffffffff && forbid_dac > 0) {
@@ -224,12 +224,6 @@ int x86_dma_supported(struct device *dev, u64 mask)
}
#endif
/* Copied from i386. Doesn't make much sense, because it will
only work for pci_alloc_coherent.
The caller just has to use GFP_DMA in this case. */
if (mask < DMA_BIT_MASK(24))
return 0;
/* Tell the device to use SAC when IOMMU force is on. This
allows the driver to use cheaper accesses in some cases.
@@ -249,6 +243,17 @@ int x86_dma_supported(struct device *dev, u64 mask)
return 1;
}
EXPORT_SYMBOL(arch_dma_supported);
int x86_dma_supported(struct device *dev, u64 mask)
{
/* Copied from i386. Doesn't make much sense, because it will
only work for pci_alloc_coherent.
The caller just has to use GFP_DMA in this case. */
if (mask < DMA_BIT_MASK(24))
return 0;
return 1;
}
static int __init pci_iommu_init(void)
{