Re: [PATCH v5 09/12] iommu: Make iommu_queue_iopf() more generic

["Liu, Jingqi" <jingqi.liu@intel.com>]

On 9/14/2023 4:56 PM, Lu Baolu wrote:
> Make iommu_queue_iopf() more generic by making the iopf_group a minimal
> set of iopf's that an iopf handler of domain should handle and respond
> to. Add domain parameter to struct iopf_group so that the handler can
> retrieve and use it directly.
>
> Change iommu_queue_iopf() to forward groups of iopf's to the domain's
> iopf handler. This is also a necessary step to decouple the sva iopf
> handling code from this interface.
>
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> ---
>   include/linux/iommu.h      |  4 ++--
>   drivers/iommu/iommu-sva.h  |  6 ++---
>   drivers/iommu/io-pgfault.c | 49 ++++++++++++++++++++++++++++----------
>   drivers/iommu/iommu-sva.c  |  3 +--
>   4 files changed, 42 insertions(+), 20 deletions(-)
>
......

> @@ -112,6 +110,7 @@ int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
>   {
>   	int ret;
>   	struct iopf_group *group;
> +	struct iommu_domain *domain;
>   	struct iopf_fault *iopf, *next;
>   	struct iommu_fault_param *iopf_param;
>   	struct dev_iommu *param = dev->iommu;
> @@ -143,6 +142,19 @@ int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
>   		return 0;
>   	}
>   
> +	if (fault->prm.flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID)
> +		domain = iommu_get_domain_for_dev_pasid(dev, fault->prm.pasid, 0);
> +	else
> +		domain = iommu_get_domain_for_dev(dev);
> +
> +	if (!domain || !domain->iopf_handler) {

Does it need to check if 'domain' is error ?  Like below:

          if (!domain || IS_ERR(domain) || !domain->iopf_handler)
Thanks,
Jingqi