IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce. But it can only allocate hw_pagetables linked with IOAS. There are needs to support hw_pagetable allocation with parameters specified by user. For example, in nested translation, user needs to allocate hw_pagetable for the stage-1 translation (e.g. a single I/O page table or a set of I/O page tables) with user data. It also needs provide a stage-2 hw_pagetable which is linked to the GPA IOAS.
This extends IOMMU_HWPT_ALLOC to accept user specified parameter and hwpt ID in @pt_id field. Such as the user-managed stage-1 hwpt, which requires a parent hwpt to point to stage-2 translation.
enum iommu_hwpt_type is defined to differentiate the user parameters use by different usages. For the allocations that don't require user parameter, IOMMU_HWPT_TYPE_DEFAULT is defined for backward compatibility. Other types would be added by future iommu vendor driver extensions.
Co-developed-by: Nicolin Chen nicolinc@nvidia.com Signed-off-by: Nicolin Chen nicolinc@nvidia.com Signed-off-by: Yi Liu yi.l.liu@intel.com --- drivers/iommu/iommufd/hw_pagetable.c | 94 +++++++++++++++++++++++++--- drivers/iommu/iommufd/main.c | 2 +- include/uapi/linux/iommufd.h | 30 +++++++++ 3 files changed, 115 insertions(+), 11 deletions(-)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index 6e45ec0a66fa..64e7cf7142e1 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -165,34 +165,106 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, return ERR_PTR(rc); }
+/* + * size of page table type specific data, indexed by + * enum iommu_hwpt_type. + */ +static const size_t iommufd_hwpt_alloc_data_size[] = { + [IOMMU_HWPT_TYPE_DEFAULT] = 0, +}; + int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) { struct iommu_hwpt_alloc *cmd = ucmd->cmd; - struct iommufd_hw_pagetable *hwpt; + struct iommufd_hw_pagetable *hwpt, *parent = NULL; + struct iommufd_object *pt_obj; struct iommufd_device *idev; struct iommufd_ioas *ioas; + const struct iommu_ops *ops; + void *data = NULL; + u32 klen; int rc;
- if (cmd->flags) + if (cmd->__reserved || cmd->flags) return -EOPNOTSUPP;
idev = iommufd_get_device(ucmd, cmd->dev_id); if (IS_ERR(idev)) return PTR_ERR(idev);
- ioas = iommufd_get_ioas(ucmd, cmd->pt_id); - if (IS_ERR(ioas)) { - rc = PTR_ERR(ioas); + ops = dev_iommu_ops(idev->dev); + if (!ops) { + rc = -EOPNOTSUPP; goto out_put_idev; }
+ /* Only support IOMMU_HWPT_TYPE_DEFAULT for now */ + if (cmd->data_type != IOMMU_HWPT_TYPE_DEFAULT) { + rc = -EINVAL; + goto out_put_idev; + } + + pt_obj = iommufd_get_object(ucmd->ictx, cmd->pt_id, IOMMUFD_OBJ_ANY); + if (IS_ERR(pt_obj)) { + rc = -EINVAL; + goto out_put_idev; + } + + switch (pt_obj->type) { + case IOMMUFD_OBJ_IOAS: + ioas = container_of(pt_obj, struct iommufd_ioas, obj); + break; + case IOMMUFD_OBJ_HW_PAGETABLE: + /* pt_id points HWPT only when data_type is !IOMMU_HWPT_TYPE_DEFAULT */ + if (cmd->data_type == IOMMU_HWPT_TYPE_DEFAULT) { + rc = -EINVAL; + goto out_put_pt; + } + + parent = container_of(pt_obj, struct iommufd_hw_pagetable, obj); + /* + * Cannot allocate user-managed hwpt linking to auto_created + * hwpt. If the parent hwpt is already a user-managed hwpt, + * don't allocate another user-managed hwpt linking to it. + */ + if (parent->auto_domain || parent->parent) { + rc = -EINVAL; + goto out_put_pt; + } + ioas = parent->ioas; + break; + default: + rc = -EINVAL; + goto out_put_pt; + } + + klen = iommufd_hwpt_alloc_data_size[cmd->data_type]; + if (klen) { + if (!cmd->data_len) { + rc = -EINVAL; + goto out_put_pt; + } + + data = kzalloc(klen, GFP_KERNEL); + if (!data) { + rc = -ENOMEM; + goto out_put_pt; + } + + rc = copy_struct_from_user(data, klen, + u64_to_user_ptr(cmd->data_uptr), + cmd->data_len); + if (rc) + goto out_free_data; + } + mutex_lock(&ioas->mutex); hwpt = iommufd_hw_pagetable_alloc(ucmd->ictx, ioas, idev, - NULL, NULL, false); + parent, data, false); mutex_unlock(&ioas->mutex); if (IS_ERR(hwpt)) { rc = PTR_ERR(hwpt); - goto out_put_ioas; + goto out_free_data; }
cmd->out_hwpt_id = hwpt->obj.id; @@ -200,12 +272,14 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) if (rc) goto out_hwpt; iommufd_object_finalize(ucmd->ictx, &hwpt->obj); - goto out_put_ioas; + goto out_free_data;
out_hwpt: iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj); -out_put_ioas: - iommufd_put_object(&ioas->obj); +out_free_data: + kfree(data); +out_put_pt: + iommufd_put_object(pt_obj); out_put_idev: iommufd_put_object(&idev->obj); return rc; diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index f079c0bda46b..7ab1e2c638a1 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -295,7 +295,7 @@ struct iommufd_ioctl_op { static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id), IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc, - __reserved), + data_uptr), IOCTL_OP(IOMMU_DEVICE_GET_HW_INFO, iommufd_device_get_hw_info, struct iommu_hw_info, __reserved), IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl, diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 4ac525897b82..48781ff40a37 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -347,6 +347,14 @@ struct iommu_vfio_ioas { }; #define IOMMU_VFIO_IOAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VFIO_IOAS)
+/** + * enum iommu_hwpt_type - IOMMU HWPT Type + * @IOMMU_HWPT_TYPE_DEFAULT: default + */ +enum iommu_hwpt_type { + IOMMU_HWPT_TYPE_DEFAULT, +}; + /** * struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC) * @size: sizeof(struct iommu_hwpt_alloc) @@ -355,12 +363,31 @@ struct iommu_vfio_ioas { * @pt_id: The IOAS 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_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 normal HWPT will be created with the mappings from the given IOAS. + * The @data_type for its allocation can be set to IOMMU_HWPT_TYPE_DEFAULT, or + * another type (being listed below) to specialize a kernel-managed HWPT. + * + * A user-managed 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. The @data_type must not be set to IOMMU_HWPT_TYPE_DEFAULT but a + * pre-defined type corresponding to the underlying IOMMU hardware. + * + * If the @data_type is set to IOMMU_HWPT_TYPE_DEFAULT, both the @data_len and + * the @data_uptr will be ignored. Otherwise, both of them must be given. + * + * +==============================+=====================================+===========+ + * | @data_type | Data structure in @data_uptr | @pt_id | + * +------------------------------+-------------------------------------+-----------+ + * | IOMMU_HWPT_TYPE_DEFAULT | N/A | IOAS | + * +------------------------------+-------------------------------------+-----------+ */ struct iommu_hwpt_alloc { __u32 size; @@ -369,6 +396,9 @@ struct iommu_hwpt_alloc { __u32 pt_id; __u32 out_hwpt_id; __u32 __reserved; + __u32 data_type; + __u32 data_len; + __aligned_u64 data_uptr; }; #define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC)