Re: [PATCH v2 03/10] iommu/arm-smmu-v3: Look for existing iotlb tag in smmu_domain->invs

Jason Gunthorpe
2026-01-26T21:03:09Z

On Wed, Jan 21, 2026 at 05:24:21PM -0800, Nicolin Chen wrote:
> Once arm_smmu_attach_prepare() installs an iotlb tag to smmu_domain->invs,
> arm_smmu_domain_get_iotlb_tag() callers should get the tag from the array.
>
> Only the arm_smmu_domain_get_iotlb_tag() caller for new_smmu_domain in the
> arm_smmu_attach_prepare_invs() will be allowed to allocate a new tag.

It would be nicer to have two functions 'alloc' and 'find' instead of
the bool. Alloc would call find.

The logic looks sound otherwise

Jason