RE: [PATCH v2 2/3] iommufd/tsm: add vdevice TSM bind/unbind ioctl

[Tian, Kevin]

> From: Aneesh Kumar K.V (Arm) <aneesh.kumar@xxxxxxxxxx>
> Sent: Monday, March 9, 2026 7:17 PM
> 
> Introduce IOMMU_VDEVICE_TSM_OP to allow userspace to issue TSM
> bind/unbind
> operations for an iommufd vdevice.

How many ops are planned? If just a few I'd prefer to openly defining
it:

	IOMMU_VDEVICE_ALLOC,
	IOMMU_VDEVICE_TSM_BIND,
	IOMMU_VDEVICE_TSM_UNBIND,

just like how we did for IOAS.

> @@ -432,6 +432,7 @@ union ucmd_buffer {
>  	struct iommu_veventq_alloc veventq;
>  	struct iommu_vfio_ioas vfio_ioas;
>  	struct iommu_viommu_alloc viommu;
> +	struct iommu_vdevice_tsm_op tsm_op;

please follow the alphabetical order

> @@ -493,6 +494,8 @@ static const struct iommufd_ioctl_op
> iommufd_ioctl_ops[] = {
>  		 __reserved),
>  	IOCTL_OP(IOMMU_VIOMMU_ALLOC, iommufd_viommu_alloc_ioctl,
>  		 struct iommu_viommu_alloc, out_viommu_id),
> +	IOCTL_OP(IOMMU_VDEVICE_TSM_OP,
> iommufd_vdevice_tsm_op_ioctl,
> +		 struct iommu_vdevice_tsm_op, vdevice_id),

ditto

> +int iommufd_vdevice_tsm_op_ioctl(struct iommufd_ucmd *ucmd)
> +{
> +	int rc;
> +	struct kvm *kvm;
> +	struct iommufd_vdevice *vdev;
> +	struct iommu_vdevice_tsm_op *cmd = ucmd->cmd;
> +
> +	if (cmd->flags)
> +		return -EOPNOTSUPP;
> +
> +	vdev = container_of(iommufd_get_object(ucmd->ictx, cmd-
> >vdevice_id,
> +					       IOMMUFD_OBJ_VDEVICE),
> +			    struct iommufd_vdevice, obj);
> +	if (IS_ERR(vdev))
> +		return PTR_ERR(vdev);
> +
> +	if (!vdev->viommu->kvm_filp) {
> +		rc = -ENODEV;
> +		goto out_put_vdev;
> +	}
> +
> +	kvm = vdev->viommu->kvm_filp->private_data;
> +	if (!kvm) {
> +		rc = -ENODEV;
> +		goto out_put_vdev;
> +	}

	if (!vdev->viommu->kvm_filp ||
	    !vdev->viommu->kvm_filp->private_data) {
		rc = -ENODEV;
		goto out_put_vdev;
	}

	kvm = vdev->viommu->kvm_filp->private_data;