From eecfffc154ffbfe70686a9905c090b488778c28e Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Fri, 12 Sep 2008 19:42:33 +0900 Subject: iommu: add iommu_device_max_index IOMMU helper function This function helps IOMMUs to know the highest address that a device can access to. Signed-off-by: FUJITA Tomonori Signed-off-by: Ingo Molnar --- include/linux/iommu-helper.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include') diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h index c975caf75385..58f41107e4ae 100644 --- a/include/linux/iommu-helper.h +++ b/include/linux/iommu-helper.h @@ -1,3 +1,13 @@ +static inline unsigned long iommu_device_max_index(unsigned long size, + unsigned long offset, + u64 dma_mask) +{ + if (size + offset > dma_mask) + return dma_mask - offset + 1; + else + return size; +} + extern int iommu_is_span_boundary(unsigned int index, unsigned int nr, unsigned long shift, unsigned long boundary_size); -- cgit v1.2.2