RE: [PATCH 06/12] iommu/vt-d: Use cache_tag_flush_cm_range() in iotlb_sync_map

From: Tian, Kevin
Date: Thu Mar 28 2024 - 03:48:49 EST


> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Sent: Monday, March 25, 2024 10:17 AM
>
> The iotlb_sync_map callback is called by the iommu core after non-present
> to present mappings are created. The iommu driver uses this callback to
> invalidate caches if IOMMU is working in caching mode and second-only
> translation is used for the domain. Use cache_tag_flush_cm_range() in this
> callback.
>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> ---
> drivers/iommu/intel/iommu.c | 22 +---------------------
> 1 file changed, 1 insertion(+), 21 deletions(-)
>
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 1c03d2dafb9d..2dcab1e5cd4d 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -1504,20 +1504,6 @@ static void iommu_flush_iotlb_psi(struct
> intel_iommu *iommu,
> iommu_flush_dev_iotlb(domain, addr, mask);
> }
>
> -/* Notification for newly created mappings */
> -static void __mapping_notify_one(struct intel_iommu *iommu, struct
> dmar_domain *domain,
> - unsigned long pfn, unsigned int pages)
> -{
> - /*
> - * It's a non-present to present mapping. Only flush if caching mode
> - * and second level.
> - */
> - if (cap_caching_mode(iommu->cap) && !domain->use_first_level)
> - iommu_flush_iotlb_psi(iommu, domain, pfn, pages, 0, 1);
> - else
> - iommu_flush_write_buffer(iommu);
> -}

iommu_flush_write_buffer is for a quite different issue. it's clearer to
keep it separated from the iotlb helpers.