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

[Aneesh Kumar K . V]

"Tian, Kevin" <kevin.tian@xxxxxxxxx> writes:

>> 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.
>

Right now only TSM_BIND and TSM_UNBIND. This was done based on earlier
review feedback.

https://lore.kernel.org/all/20250530181842.GU233377@xxxxxxxxxx/

>
>> @@ -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;

-aneesh