> On Jun 1, 2021, at 8:59 AM, Robin Murphy <robin.mur...@arm.com> wrote: > > On 2021-05-02 07:59, Nadav Amit wrote: >> From: Nadav Amit <na...@vmware.com> >> Some IOMMU architectures perform invalidations regardless of the page >> size. In such architectures there is no need to sync when the page size >> changes or to regard pgsize when making interim flush in >> iommu_iotlb_gather_add_page(). >> Add a "ignore_gather_pgsize" property for each IOMMU-ops to decide >> whether gather's pgsize is tracked and triggers a flush. > > I've objected before[1], and I'll readily object again ;) > > I still think it's very silly to add a bunch of indirection all over the > place to make a helper function not do the main thing it's intended to help > with. If you only need trivial address gathering then it's far simpler to > just implement trivial address gathering. I suppose if you really want to you > could factor out another helper to share the 5 lines of code which ended up > in mtk-iommu (see commit f21ae3b10084).
Thanks, Robin. I read your comments but I cannot fully understand the alternative that you propose, although I do understand your objection to the indirection “ignore_gather_pgsize”. Would it be ok if “ignore_gather_pgsize" was provided as an argument for iommu_iotlb_gather_add_page()? In general, I can live without this patch. It probably would have negligent impact on performance anyhow. Regards, Nadav _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
