diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 2a165010a1c1..4c780efff169 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -78,6 +78,24 @@ #define LEVEL_STRIDE (9) #define LEVEL_MASK (((u64)1 << LEVEL_STRIDE) - 1) +/* + * This bitmap is used to advertise the page sizes our hardware support + * to the IOMMU core, which will then use this information to split + * physically contiguous memory regions it is mapping into page sizes + * that we support. + * + * Traditionally the IOMMU core just handed us the mappings directly, + * after making sure the size is an order of a 4KiB page and that the + * mapping has natural alignment. + * + * To retain this behavior, we currently advertise that we support + * all page sizes that are an order of 4KiB. + * + * If at some point we'd like to utilize the IOMMU core's new behavior, + * we could change this to advertise the real page sizes we support. + */ +#define INTEL_IOMMU_PGSIZES (~0xFFFUL) + static inline int agaw_to_level(int agaw) { return agaw + 2; @@ -4066,6 +4084,7 @@ static struct iommu_ops intel_iommu_ops = { .unmap = intel_iommu_unmap, .iova_to_phys = intel_iommu_iova_to_phys, .domain_has_cap = intel_iommu_domain_has_cap, + .pgsize_bitmap = INTEL_IOMMU_PGSIZES, }; static void __devinit quirk_iommu_rwbf(struct pci_dev *dev)