On Sat, Jan 18, 2025 at 04:23:22PM +0800, Yi Liu wrote:
> On 2025/1/11 11:32, Nicolin Chen wrote:
> > "attach_handle" was added exclusively for the iommufd_fault_iopf_handler()
> > used by IOPF/PRI use cases, along with the "fault_data". Now, the iommufd
> > version of sw_msi function will resue the attach_handle and fault_data for
> > a non-fault case.
> >
> > Move the attach_handle part out of the fault.c file to make it generic for
> > all cases. Simplify the remaining fault specific routine to attach/detach.
>
> I guess you can send it separately since both of our series need it. :)
Jason, would you like to take this patch separately? I can send
it prior to two big series for a quick review after rc1. It'll
likely impact the vEVENTQ series too.
> > +static int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt,
> > + struct iommufd_device *idev)
> > +{
> > + struct iommufd_attach_handle *handle;
> > + int rc;
> > +
> > + if (hwpt->fault) {
> > + rc = iommufd_fault_domain_attach_dev(hwpt, idev, true);
> > + if (rc)
> > + return rc;
> > + }
> > +
> > + handle = kzalloc(sizeof(*handle), GFP_KERNEL);
> > + if (!handle) {
> > + rc = -ENOMEM;
> > + goto out_fault_detach;
> > + }
> > +
> > + handle->idev = idev;
> > + rc = iommu_attach_group_handle(hwpt->domain, idev->igroup->group,
> > + &handle->handle);
> > + if (rc)
> > + goto out_free_handle;
> > +
> > + return 0;
> > +
> > +out_free_handle:
> > + kfree(handle);
> > + handle = NULL;
> > +out_fault_detach:
> > + if (hwpt->fault)
> > + iommufd_fault_domain_detach_dev(hwpt, idev, handle, true);
> > + return rc;
> > +}
Here the revert path passes in a handle=NULL..
> > void iommufd_fault_domain_detach_dev(struct iommufd_hw_pagetable *hwpt,
> > - struct iommufd_device *idev)
> > + struct iommufd_device *idev,
> > + struct iommufd_attach_handle *handle,
> > + bool disable_iopf)
> > {
> > + if (handle)
> > + iommufd_auto_response_faults(hwpt, handle);
>
> no need to check handle. After this patch, both the non-fault and the fault
> path will allocate handle. It cannot be used to isolate fault and non-fault
> path. Also, the callers of iommufd_fault_domain_detach_dev() will check
> hwpt->fault before calling it. So just call iommufd_auto_response_faults().
..so we still need this !NULL validation? :-/
Thanks
Nicolin
