On Fri, Oct 25, 2024 at 04:49:42PM -0700, Nicolin Chen wrote:
Add a new IOMMUFD_OBJ_VIOMMU with an iommufd_viommu structure to represent a slice of physical IOMMU device passed to or shared with a user space VM. This slice, now a vIOMMU object, is a group of virtualization resources of a physical IOMMU's, such as:
- Security namespace for guest owned ID, e.g. guest-controlled cache tags
- 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
- Non-affiliated event reporting
Add a new viommu_alloc op in iommu_ops, for drivers to allocate their own vIOMMU structures. And this allocation also needs a free(), so add struct iommufd_viommu_ops.
To simplify a vIOMMU allocation, provide a iommufd_viommu_alloc() helper. It's suggested that a driver should embed a core-level viommu structure in its driver-level viommu struct and call the iommufd_viommu_alloc() helper, meanwhile the driver can also implement a viommu ops: struct my_driver_viommu { struct iommufd_viommu core; /* driver-owned properties/features */ .... };
static const struct iommufd_viommu_ops my_driver_viommu_ops = { .free = my_driver_viommu_free, /* future ops for virtualization features */ .... }; static struct iommufd_viommu my_driver_viommu_alloc(...) { struct my_driver_viommu *my_viommu = iommufd_viommu_alloc(ictx, my_driver_viommu, core, my_driver_viommu_ops); /* Init my_viommu and related HW feature */ .... return &my_viommu->core; } static struct iommu_domain_ops my_driver_domain_ops = { .... .viommu_alloc = my_driver_viommu_alloc, };To make the Kernel config work between a driver and the iommufd core, move the _iommufd_object_alloc helper into a new driver.c file that builds with CONFIG_IOMMUFD_DRIVER.
Suggested-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Nicolin Chen nicolinc@nvidia.com
drivers/iommu/iommufd/Makefile | 2 +- drivers/iommu/iommufd/iommufd_private.h | 4 -- include/linux/iommu.h | 14 +++++++ include/linux/iommufd.h | 53 +++++++++++++++++++++++++ drivers/iommu/iommufd/driver.c | 38 ++++++++++++++++++ drivers/iommu/iommufd/main.c | 32 --------------- 6 files changed, 106 insertions(+), 37 deletions(-) create mode 100644 drivers/iommu/iommufd/driver.c
Reviewed-by: Jason Gunthorpe jgg@nvidia.com
Jason