Re: [PATCH v4 07/10] iommu: Merge iommu_fault_event and iopf_fault

[Baolu Lu]

On 8/25/23 4:03 PM, Tian, Kevin wrote:
> > From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> > Sent: Friday, August 25, 2023 10:30 AM
> >
> > -/**
> > - * struct iommu_fault_event - Generic fault event
> > - *
> > - * Can represent recoverable faults such as a page requests or
> > - * unrecoverable faults such as DMA or IRQ remapping faults.
> > - *
> > - * @fault: fault descriptor
> > - * @list: pending fault event list, used for tracking responses
> > - */
> > -struct iommu_fault_event {
> > -	struct iommu_fault fault;
> > -	struct list_head list;
> > -};
> > -
>
> iommu_fault_event is more forward-looking if unrecoverable fault
> will be supported in future. From this angle it might make more
> sense to keep it to replace iopf_fault.

Currently IOMMU drivers use

int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
                       unsigned long iova, int flags)

to report unrecoverable faults. There is no need for a generic fault
event structure.

So alternatively, we can use iopf_fault for now and consolidate a
generic fault data structure when there is a real need.

Best regards,
baolu