From: Lu Baolu <[email protected]> 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. Signed-off-by: Lu Baolu <[email protected]> Reviewed-by: Kevin Tian <[email protected]> Signed-off-by: Nicolin Chen <[email protected]> Signed-off-by: Yi Liu <[email protected]> --- include/linux/iommu.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 3861d66b65c1..ce08a3c41446 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -65,6 +65,9 @@ struct iommu_domain_geometry { #define __IOMMU_DOMAIN_SVA (1U << 4) /* Shared process address space */ +#define __IOMMU_DOMAIN_NESTED (1U << 5) /* 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 @@ -91,6 +94,7 @@ 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; -- 2.34.1
