Re: [PATCH v4 1/6] iommu: Add a per domain PASID for DMA API

Baolu Lu
2022-05-19T06:50:56Z

On 2022/5/19 02:21, Jacob Pan wrote:
> DMA requests tagged with PASID can target individual IOMMU domains.
> Introduce a domain-wide PASID for DMA API, it will be used on the same
> mapping as legacy DMA without PASID. Let it be IOVA or PA in case of
> identity domain.
>
> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
> ---
> include/linux/iommu.h | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index 9405034e3013..36ad007084cc 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -106,6 +106,8 @@ struct iommu_domain {
> enum iommu_page_response_code (*iopf_handler)(struct iommu_fault *fault,
> void *data);
> void *fault_data;
> + ioasid_t dma_pasid; /* Used for DMA requests with PASID */

This looks more suitable for iommu_dma_cookie?

> + atomic_t dma_pasid_users;
> };
>
> static inline bool iommu_is_dma_domain(struct iommu_domain *domain)

Best regards,
baolu