From: Lu Baolu baolu.lu@linux.intel.com
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 baolu.lu@linux.intel.com Signed-off-by: Nicolin Chen nicolinc@nvidia.com Signed-off-by: Yi Liu yi.l.liu@intel.com Reviewed-by: Kevin Tian kevin.tian@intel.com Reviewed-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com --- include/linux/iommu.h | 4 ++++ 1 file changed, 4 insertions(+)
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;