From 4ff542163397073f86eda484318d61980ff1031d Mon Sep 17 00:00:00 2001 From: Yi Liu Date: Thu, 28 Sep 2023 00:15:26 -0700 Subject: [PATCH] iommufd: Support allocating nested parent domain Extend IOMMU_HWPT_ALLOC to allocate domains to be used as parent (stage-2) in nested translation. Add IOMMU_HWPT_ALLOC_NEST_PARENT to the uAPI. Link: https://lore.kernel.org/r/20230928071528.26258-5-yi.l.liu@intel.com Signed-off-by: Yi Liu Reviewed-by: Kevin Tian Reviewed-by: Lu Baolu Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommufd/hw_pagetable.c | 5 ++++- include/uapi/linux/iommufd.h | 12 +++++++++++- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index 5be7a31cbd9c..8b3d2875d642 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -83,6 +83,9 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, lockdep_assert_held(&ioas->mutex); + if (flags && !ops->domain_alloc_user) + return ERR_PTR(-EOPNOTSUPP); + hwpt = iommufd_object_alloc(ictx, hwpt, IOMMUFD_OBJ_HW_PAGETABLE); if (IS_ERR(hwpt)) return hwpt; @@ -154,7 +157,7 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) struct iommufd_ioas *ioas; int rc; - if (cmd->flags || cmd->__reserved) + if ((cmd->flags & (~IOMMU_HWPT_ALLOC_NEST_PARENT)) || cmd->__reserved) return -EOPNOTSUPP; idev = iommufd_get_device(ucmd, cmd->dev_id); diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index b4ba0c0cbab6..4a7c5c8fdbb4 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -347,10 +347,20 @@ struct iommu_vfio_ioas { }; #define IOMMU_VFIO_IOAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VFIO_IOAS) +/** + * enum iommufd_hwpt_alloc_flags - Flags for HWPT allocation + * @IOMMU_HWPT_ALLOC_NEST_PARENT: If set, allocate a domain which can serve + * as the parent domain in the nesting + * configuration. + */ +enum iommufd_hwpt_alloc_flags { + IOMMU_HWPT_ALLOC_NEST_PARENT = 1 << 0, +}; + /** * struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC) * @size: sizeof(struct iommu_hwpt_alloc) - * @flags: Must be 0 + * @flags: Combination of enum iommufd_hwpt_alloc_flags * @dev_id: The device to allocate this HWPT for * @pt_id: The IOAS to connect this HWPT to * @out_hwpt_id: The ID of the new HWPT