From 54d606816b32401de5431f6776a78b1de135bfa2 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Wed, 25 Oct 2023 21:39:29 -0700 Subject: iommu: Add IOMMU_DOMAIN_NESTED Introduce a new domain type for a user I/O page table, which is nested on top of another user space address represented by a PAGING domain. This new domain can be allocated by the domain_alloc_user op, and attached to a device through the existing iommu_attach_device/group() interfaces. The mappings of a nested domain are managed by user space software, so it is not necessary to have map/unmap callbacks. Link: https://lore.kernel.org/r/20231026043938.63898-2-yi.l.liu@intel.com Signed-off-by: Lu Baolu Signed-off-by: Nicolin Chen Signed-off-by: Yi Liu Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe --- include/linux/iommu.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/iommu.h') diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 1d42bdb37cbc..bc303cb2af37 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -67,6 +67,9 @@ struct iommu_domain_geometry { #define __IOMMU_DOMAIN_SVA (1U << 4) /* Shared process address space */ +#define __IOMMU_DOMAIN_NESTED (1U << 6) /* User-managed address space nested + on a stage-2 translation */ + #define IOMMU_DOMAIN_ALLOC_FLAGS ~__IOMMU_DOMAIN_DMA_FQ /* * This are the possible domain-types @@ -93,6 +96,7 @@ struct iommu_domain_geometry { __IOMMU_DOMAIN_DMA_API | \ __IOMMU_DOMAIN_DMA_FQ) #define IOMMU_DOMAIN_SVA (__IOMMU_DOMAIN_SVA) +#define IOMMU_DOMAIN_NESTED (__IOMMU_DOMAIN_NESTED) struct iommu_domain { unsigned type; -- cgit