Hi Jason,
On Thu, 2 Mar 2023 08:57:48 -0400, Jason Gunthorpe <jgg@xxxxxxxxxx> wrote:
> On Thu, Mar 02, 2023 at 09:47:00AM +0000, Tian, Kevin wrote:
> > > From: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> > > Sent: Thursday, March 2, 2023 9:00 AM
> > >
> > > static int idxd_enable_system_pasid(struct idxd_device *idxd)
> > > {
> > > - return -EOPNOTSUPP;
> > > + struct pci_dev *pdev = idxd->pdev;
> > > + struct device *dev = &pdev->dev;
> > > + struct iommu_domain *domain;
> > > + union gencfg_reg gencfg;
> > > + ioasid_t pasid;
> > > + int ret;
> > > +
> > > + domain = iommu_get_domain_for_dev(dev);
> > > + if (!domain || domain->type == IOMMU_DOMAIN_BLOCKED)
> > > + return -EPERM;
> >
> > what about UNMANAGED?
>
> Why are we checking this anyhow?
>
> Get the domain the DMA API is using and feed it to
> iommu_attach_device_pasid(). If the driver can't mirror the DMA API's
> domain onto the PASID then it will just fail the attach. A domain
> cannot even be NULL on x86.
makes sense,
Thanks,
Jacob
