Commit 4fcf8544 authored by Will Deacon's avatar Will Deacon
Browse files

iommu: Introduce iommu_iotlb_gather_add_page() 



Introduce a helper function for drivers to use when updating an
iommu_iotlb_gather structure in response to an ->unmap() call, rather
than having to open-code the logic in every page-table implementation.

Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent a7d20dc1

include/linux/iommu.h

+31 −0
Original line number Diff line number Diff line
@@ -507,6 +507,31 @@ static inline void iommu_tlb_sync(struct iommu_domain *domain, 
	iommu_iotlb_gather_init(iotlb_gather);

}



static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,

					       struct iommu_iotlb_gather *gather,

					       unsigned long iova, size_t size)

{

	unsigned long start = iova, end = start + size;



	/*

	 * If the new page is disjoint from the current range or is mapped at

	 * a different granularity, then sync the TLB so that the gather

	 * structure can be rewritten.

	 */

	if (gather->pgsize != size ||

	    end < gather->start || start > gather->end) {

		if (gather->pgsize)

			iommu_tlb_sync(domain, gather);

		gather->pgsize = size;

	}



	if (gather->end < end)

		gather->end = end;



	if (gather->start > start)

		gather->start = start;

}



/* PCI device grouping function */

extern struct iommu_group *pci_device_group(struct device *dev);

/* Generic device grouping function */
@@ -847,6 +872,12 @@ static inline void iommu_iotlb_gather_init(struct iommu_iotlb_gather *gather) 
{

}



static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,

					       struct iommu_iotlb_gather *gather,

					       unsigned long iova, size_t size)

{

}



static inline void iommu_device_unregister(struct iommu_device *iommu)

{

}