Now a VIOMMU can wrap a shareable nested parent HWPT. So, it can act like a nested parent HWPT to allocate a nested HWPT.
Support that in the IOMMU_HWPT_ALLOC ioctl handler, and update its kdoc.
Also, associate a viommu to an allocating nested HWPT.
Signed-off-by: Nicolin Chen nicolinc@nvidia.com --- drivers/iommu/iommufd/hw_pagetable.c | 24 ++++++++++++++++++++++-- drivers/iommu/iommufd/iommufd_private.h | 1 + include/uapi/linux/iommufd.h | 12 ++++++------ 3 files changed, 29 insertions(+), 8 deletions(-)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index c21bb59c4022..06adbcc304bc 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -57,6 +57,9 @@ void iommufd_hwpt_nested_destroy(struct iommufd_object *obj) container_of(obj, struct iommufd_hwpt_nested, common.obj);
__iommufd_hwpt_destroy(&hwpt_nested->common); + + if (hwpt_nested->viommu) + refcount_dec(&hwpt_nested->viommu->obj.users); refcount_dec(&hwpt_nested->parent->common.obj.users); }
@@ -213,6 +216,7 @@ iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, */ static struct iommufd_hwpt_nested * iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx, + struct iommufd_viommu *viommu, struct iommufd_hwpt_paging *parent, struct iommufd_device *idev, u32 flags, const struct iommu_user_data *user_data) @@ -234,13 +238,16 @@ iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx, return ERR_CAST(hwpt_nested); hwpt = &hwpt_nested->common;
+ if (viommu) + refcount_inc(&viommu->obj.users); + hwpt_nested->viommu = viommu; refcount_inc(&parent->common.obj.users); hwpt_nested->parent = parent;
hwpt->domain = ops->domain_alloc_user(idev->dev, flags & ~IOMMU_HWPT_FAULT_ID_VALID, parent->common.domain, - NULL, user_data); + viommu, user_data); if (IS_ERR(hwpt->domain)) { rc = PTR_ERR(hwpt->domain); hwpt->domain = NULL; @@ -307,7 +314,7 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) struct iommufd_hwpt_nested *hwpt_nested;
hwpt_nested = iommufd_hwpt_nested_alloc( - ucmd->ictx, + ucmd->ictx, NULL, container_of(pt_obj, struct iommufd_hwpt_paging, common.obj), idev, cmd->flags, &user_data); @@ -316,6 +323,19 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) goto out_unlock; } hwpt = &hwpt_nested->common; + } else if (pt_obj->type == IOMMUFD_OBJ_VIOMMU) { + struct iommufd_hwpt_nested *hwpt_nested; + struct iommufd_viommu *viommu; + + viommu = container_of(pt_obj, struct iommufd_viommu, obj); + hwpt_nested = iommufd_hwpt_nested_alloc( + ucmd->ictx, viommu, viommu->hwpt, idev, + cmd->flags, &user_data); + if (IS_ERR(hwpt_nested)) { + rc = PTR_ERR(hwpt_nested); + goto out_unlock; + } + hwpt = &hwpt_nested->common; } else { rc = -EINVAL; goto out_put_pt; diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 0e3755408911..443575fd3dd4 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -313,6 +313,7 @@ struct iommufd_hwpt_paging { struct iommufd_hwpt_nested { struct iommufd_hw_pagetable common; struct iommufd_hwpt_paging *parent; + struct iommufd_viommu *viommu; };
static inline bool hwpt_is_paging(struct iommufd_hw_pagetable *hwpt) diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index ed6cdc2e0be1..0e384331a9c8 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -430,7 +430,7 @@ enum iommu_hwpt_data_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 or HWPT to connect this HWPT to + * @pt_id: The IOAS or HWPT or VIOMMU to connect this HWPT to * @out_hwpt_id: The ID of the new HWPT * @__reserved: Must be 0 * @data_type: One of enum iommu_hwpt_data_type @@ -449,11 +449,11 @@ enum iommu_hwpt_data_type { * IOMMU_HWPT_DATA_NONE. The HWPT can be allocated as a parent HWPT for a * nesting configuration by passing IOMMU_HWPT_ALLOC_NEST_PARENT via @flags. * - * A user-managed nested HWPT will be created from a given parent HWPT via - * @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 @data_type - * must be set to a pre-defined type corresponding to an I/O page table - * type supported by the underlying IOMMU hardware. + * A user-managed nested HWPT will be created from a given VIOMMU (wrapping a + * parent HWPT) or a parent HWPT via @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 @data_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 @data_type is set to IOMMU_HWPT_DATA_NONE, @data_len and * @data_uptr should be zero. Otherwise, both @data_len and @data_uptr