Commit 4ff54216 authored by Yi Liu's avatar Yi Liu Committed by Jason Gunthorpe
Browse files

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: default avatarYi Liu <yi.l.liu@intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 89d63875

drivers/iommu/iommufd/hw_pagetable.c

+4 −1
Original line number Diff line number Diff line
@@ -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);

include/uapi/linux/iommufd.h

+11 −1
Original line number Diff line number Diff line
@@ -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