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| author |   Nicolin Chen <nicolinc@nvidia.com> | 2025-03-11 12:44:29 -0700 |
|---|---|---|
| committer |   Jason Gunthorpe <jgg@nvidia.com> | 2025-03-18 14:17:48 -0300 |
| commit | 2ec0458eb0e5a84d80f82667e358c4f2c187d2e4 (patch) | |
| tree | 690f1564eb8480865699f2c5a1c401e8190928cf | |
| parent | iommufd/selftest: Add IOMMU_VEVENTQ_ALLOC test coverage (diff) | |
| download | wireguard-linux-2ec0458eb0e5a84d80f82667e358c4f2c187d2e4.tar.xz wireguard-linux-2ec0458eb0e5a84d80f82667e358c4f2c187d2e4.zip | |
Documentation: userspace-api: iommufd: Update FAULT and VEVENTQ
With the introduction of the new objects, update the doc to reflect that.
Link: https://patch.msgid.link/r/09829fbc218872d242323d8834da4bec187ce6f4.1741719725.git.nicolinc@nvidia.com
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
| -rw-r--r-- | Documentation/userspace-api/iommufd.rst | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/Documentation/userspace-api/iommufd.rst b/Documentation/userspace-api/iommufd.rst index 70289d6815d2..b0df15865dec 100644 --- a/Documentation/userspace-api/iommufd.rst +++ b/Documentation/userspace-api/iommufd.rst @@ -63,6 +63,13 @@ Following IOMMUFD objects are exposed to userspace: space usually has mappings from guest-level I/O virtual addresses to guest- level physical addresses. +- IOMMUFD_FAULT, representing a software queue for an HWPT reporting IO page + faults using the IOMMU HW's PRI (Page Request Interface). This queue object + provides user space an FD to poll the page fault events and also to respond + to those events. A FAULT object must be created first to get a fault_id that + could be then used to allocate a fault-enabled HWPT via the IOMMU_HWPT_ALLOC + command by setting the IOMMU_HWPT_FAULT_ID_VALID bit in its flags field. + - IOMMUFD_OBJ_VIOMMU, representing a slice of the physical IOMMU instance, passed to or shared with a VM. It may be some HW-accelerated virtualization features and some SW resources used by the VM. For examples: @@ -109,6 +116,14 @@ Following IOMMUFD objects are exposed to userspace: vIOMMU, which is a separate ioctl call from attaching the same device to an HWPT_PAGING that the vIOMMU holds. +- IOMMUFD_OBJ_VEVENTQ, representing a software queue for a vIOMMU to report its + events such as translation faults occurred to a nested stage-1 (excluding I/O + page faults that should go through IOMMUFD_OBJ_FAULT) and HW-specific events. + This queue object provides user space an FD to poll/read the vIOMMU events. A + vIOMMU object must be created first to get its viommu_id, which could be then + used to allocate a vEVENTQ. Each vIOMMU can support multiple types of vEVENTS, + but is confined to one vEVENTQ per vEVENTQ type. + All user-visible objects are destroyed via the IOMMU_DESTROY uAPI. The diagrams below show relationships between user-visible objects and kernel @@ -251,8 +266,10 @@ User visible objects are backed by following datastructures: - iommufd_device for IOMMUFD_OBJ_DEVICE. - iommufd_hwpt_paging for IOMMUFD_OBJ_HWPT_PAGING. - iommufd_hwpt_nested for IOMMUFD_OBJ_HWPT_NESTED. +- iommufd_fault for IOMMUFD_OBJ_FAULT. - iommufd_viommu for IOMMUFD_OBJ_VIOMMU. - iommufd_vdevice for IOMMUFD_OBJ_VDEVICE. +- iommufd_veventq for IOMMUFD_OBJ_VEVENTQ. Several terminologies when looking at these datastructures: |