IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce. But it can only allocate a hw_pagetable that associates to a given IOAS, i.e. only a kernel-managed hw_pagetable of IOMMU_HWPT_TYPE_DEFAULT type.
IOMMU drivers can now support user-managed hw_pagetables, for two-stage translation use cases, that require user data input from the user space. Extend the IOMMU_HWPT_ALLOC ioctl to accept non-default hwpt_type with a type specified user data. Also, update the @pt_id to accept hwpt_id too besides an ioas_id. Then, pass them to the downstream alloc_fn(). Co-developed-by: Nicolin Chen <[email protected]> Signed-off-by: Nicolin Chen <[email protected]> Signed-off-by: Yi Liu <[email protected]> --- drivers/iommu/iommufd/hw_pagetable.c | 19 ++++++++++++++++++- include/uapi/linux/iommufd.h | 23 +++++++++++++++++++++-- 2 files changed, 39 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index 90fd65859e28..ab25de149ae6 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -300,6 +300,7 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) bool flag); struct iommufd_hw_pagetable *hwpt, *parent; struct iommu_hwpt_alloc *cmd = ucmd->cmd; + struct iommu_user_data *data = NULL; struct iommufd_object *pt_obj; struct iommufd_device *idev; struct iommufd_ioas *ioas; @@ -308,6 +309,11 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) if (cmd->flags & ~IOMMU_HWPT_ALLOC_NEST_PARENT || cmd->__reserved) return -EOPNOTSUPP; + if (!cmd->data_len && cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) + return -EINVAL; + if (cmd->flags & IOMMU_HWPT_ALLOC_NEST_PARENT && + cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) + return -EINVAL; idev = iommufd_get_device(ucmd, cmd->dev_id); if (IS_ERR(idev)) @@ -340,9 +346,19 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) goto out_put_pt; } + if (cmd->data_len) { + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) { + rc = -ENOMEM; + goto out_put_pt; + } + data->uptr = u64_to_user_ptr(cmd->data_uptr); + data->len = cmd->data_len; + } + mutex_lock(mutex); hwpt = alloc_fn(ucmd->ictx, pt_obj, idev, cmd->flags, - IOMMU_HWPT_TYPE_DEFAULT, NULL, false); + cmd->hwpt_type, data, false); if (IS_ERR(hwpt)) { rc = PTR_ERR(hwpt); goto out_unlock; @@ -359,6 +375,7 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj); out_unlock: mutex_unlock(mutex); + kfree(data); out_put_pt: iommufd_put_object(pt_obj); out_put_idev: diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 3c8660fe9bb1..c46b1f772f20 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -370,15 +370,31 @@ enum iommu_hwpt_type { * @size: sizeof(struct iommu_hwpt_alloc) * @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 + * @pt_id: The IOAS or HWPT to connect this HWPT to * @out_hwpt_id: The ID of the new HWPT * @__reserved: Must be 0 + * @hwpt_type: One of enum iommu_hwpt_type + * @data_len: Length of the type specific data + * @data_uptr: User pointer to the type specific data * * Explicitly allocate a hardware page table object. This is the same object * type that is returned by iommufd_device_attach() and represents the * underlying iommu driver's iommu_domain kernel object. * - * A HWPT will be created with the IOVA mappings from the given IOAS. + * A kernel-managed HWPT will be created with the mappings from the given + * IOAS via the @pt_id. The @hwpt_type for this allocation can be set to + * either IOMMU_HWPT_TYPE_DEFAULT or a pre-defined type corresponding to + * an I/O page table type supported by the underlying IOMMU hardware. + * + * A user-managed HWPT will be created from a given parent HWPT via the + * @pt_id, in which the parent HWPT must be allocated previously via the + * same ioctl from a given IOAS (@pt_id). In this case, the @hwpt_type + * must be set to a pre-defined type corresponding to an I/O page table + * type supported by the underlying IOMMU hardware. + * + * If the @hwpt_type is set to IOMMU_HWPT_TYPE_DEFAULT, @data_len and + * @data_uptr should be zero. Otherwise, both @data_len and @data_uptr + * must be given. */ struct iommu_hwpt_alloc { __u32 size; @@ -387,6 +403,9 @@ struct iommu_hwpt_alloc { __u32 pt_id; __u32 out_hwpt_id; __u32 __reserved; + __u32 hwpt_type; + __u32 data_len; + __aligned_u64 data_uptr; }; #define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC) -- 2.34.1
