On Tue, Nov 05, 2024 at 12:04:29PM -0800, Nicolin Chen wrote: > With the introduction of the new object and its infrastructure, update the > doc to reflect that and add a new graph. > > Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> > Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx> > Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> > --- > Documentation/userspace-api/iommufd.rst | 69 ++++++++++++++++++++++++- > 1 file changed, 68 insertions(+), 1 deletion(-) > > diff --git a/Documentation/userspace-api/iommufd.rst b/Documentation/userspace-api/iommufd.rst > index 2deba93bf159..a8b7766c2849 100644 > --- a/Documentation/userspace-api/iommufd.rst > +++ b/Documentation/userspace-api/iommufd.rst > @@ -63,6 +63,37 @@ Following IOMMUFD objects are exposed to userspace: > space usually has mappings from guest-level I/O virtual addresses to guest- > level physical addresses. > > +- 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: > + * Security namespace for guest owned ID, e.g. guest-controlled cache tags > + * Non-device-affiliated event reporting, e.g. invalidation queue errors > + * Access to a sharable nesting parent pagetable across physical IOMMUs > + * Virtualization of various platforms IDs, e.g. RIDs and others > + * Delivery of paravirtualized invalidation > + * Direct assigned invalidation queues > + * Direct assigned interrupts The bullet list above is outputted in htmldocs build as long-running paragraph instead. > + Such a vIOMMU object generally has the access to a nesting parent pagetable > + to support some HW-accelerated virtualization features. So, a vIOMMU object > + must be created given a nesting parent HWPT_PAGING object, and then it would > + encapsulate that HWPT_PAGING object. Therefore, a vIOMMU object can be used > + to allocate an HWPT_NESTED object in place of the encapsulated HWPT_PAGING. Thanks. -- An old man doll... just what I always wanted! - Clara
Attachment:
signature.asc
Description: PGP signature
