[v7,01/10] iommu: Add IOMMU_DOMAIN_NESTED

Message ID 20231026043938.63898-2-yi.l.liu@intel.com
State New
Headers
Series iommufd: Add nesting infrastructure (part 1/2) |

Commit Message

Yi Liu Oct. 26, 2023, 4:39 a.m. UTC
  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(+)
  

Patch

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;