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

[Jason Gunthorpe]

On Wed, Mar 11, 2026 at 09:35:55PM +0000, Jonathan Cameron wrote:
> > +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);
> 
> I'd be tempted to do something with a helper function to simplify flow.

It is already

static inline struct iommufd_vdevice *
iommufd_get_vdevice(struct iommufd_ctx *ictx, u32 id)
{
        return container_of(iommufd_get_object(ictx, id,
                                               IOMMUFD_OBJ_VDEVICE),
                            struct iommufd_vdevice, obj);
}

> Then the helper function can do direct returns on errors given the
> iommfd_object is managed in outer function.

Use cleanup.h ? It is not the iommufd style the break things up into
little functions for error unwind reasons
 
> > +	if (!vdev->viommu->kvm_filp) {
> > +		rc = -ENODEV;
> > +		goto out_put_vdev;
> > +	}
> > +
> > +	kvm = vdev->viommu->kvm_filp->private_data;
> > +	if (!kvm) {

Ah this I don't think you should be doing. That needs a helper from
kvm

Jason