On 13/3/25 22:01, Xu Yilun wrote:
+int iommufd_vdevice_tsm_bind_ioctl(struct iommufd_ucmd *ucmd)
+{
+ struct iommu_vdevice_tsm_bind *cmd = ucmd->cmd;
+ struct iommufd_viommu *viommu;
+ struct iommufd_vdevice *vdev;
+ struct iommufd_device *idev;
+ struct tsm_tdi *tdi;
+ int rc = 0;
+
+ viommu = iommufd_get_viommu(ucmd, cmd->viommu_id);
Why need user to input viommu_id? And why get viommu here?
The viommu is always available after vdevice is allocated, is it?
I thought it may be a good idea to hold a reference while doing
tsm_tdi_bind(), likely not needed.
int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd)
{
...
vdev->viommu = viommu;
refcount_inc(&viommu->obj.users);
...
}
+ if (IS_ERR(viommu))
+ return PTR_ERR(viommu);
+
+ idev = iommufd_get_device(ucmd, cmd->dev_id);
+ if (IS_ERR(idev)) {
+ rc = PTR_ERR(idev);
+ goto out_put_viommu;
+ }
+
+ vdev = container_of(iommufd_get_object(ucmd->ictx, cmd->vdevice_id,
+ IOMMUFD_OBJ_VDEVICE),
+ struct iommufd_vdevice, obj);
+ if (IS_ERR(idev)) {
^
vdev?
yes.
+ rc = PTR_ERR(idev);
+ goto out_put_dev;
+ }
+
+ tdi = tsm_tdi_get(idev->dev);
And do we still need dev_id for the struct device *? vdevice also has
this info.
Oh, likely no. Probably leftover from multiple rebases, or me not fully
following what nature these IDs are of (some are just numbers, some are
guest bdfn).
int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd)
{
...
vdev->dev = idev->dev;
get_device(idev->dev);
...
}
+ if (!tdi) {
+ rc = -ENODEV;
+ goto out_put_vdev;
+ }
+
+ rc = tsm_tdi_bind(tdi, vdev->id, cmd->kvmfd);
+ if (rc)
+ goto out_put_tdi;
+
+ vdev->tsm_bound = true;
+
+ rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+out_put_tdi:
+ tsm_tdi_put(tdi);
+out_put_vdev:
+ iommufd_put_object(ucmd->ictx, &vdev->obj);
+out_put_dev:
+ iommufd_put_object(ucmd->ictx, &idev->obj);
+out_put_viommu:
+ iommufd_put_object(ucmd->ictx, &viommu->obj);
+ return rc;
+}
Another concern is do we need an unbind ioctl? We don't bind on vdevice
create so it seems not symmetrical we only unbind on vdevice destroy.
I'll add it as we progress. Just for now I have no flow to exercise it -
I accept the device into my SNP VM and that's it but if something in the
VM is unhappy about the device report, then we'll need to unbind and
continue using the device as untrusted. Thanks,
(sorry for late response, still going through all comments here and in
Dan's threads)
Thanks,
Yilun
--
Alexey
