Messages in this thread | | | Subject | Re: [PATCH v2 6/8] iommu: Move IOMMU pagesize check to attach_device | From | Robin Murphy <> | Date | Wed, 1 Sep 2021 19:53:23 +0100 |
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On 2021-09-01 18:14, Sven Peter wrote: > > > On Tue, Aug 31, 2021, at 23:39, Alyssa Rosenzweig wrote: >>> + if ((1 << __ffs(domain->pgsize_bitmap)) > PAGE_SIZE) { >> >> Not a fan of this construction. Could you assign `(1 << >> __ffs(domain->pgsize_bitmap))` to an appropriately named temporary (e.g >> min_io_pgsize) so it's clearer what's going on? > > Good point, will do that for the next version.
Or maybe just test "__ffs(domain->pgsize_bitmap) > PAGE_SHIFT", or perhaps even avoid shifts altogether with something like "domain->pgsize_bitmap & (PAGE_SIZE | PAGE_SIZE - 1)".
Robin.
> >> >>> + pr_warn("IOMMU page size cannot represent CPU pages.\n"); >> >> "Represent" how? >> > > Looks like I dropped an "exactly" there when taking this line from iova.c :) > > > > Thanks, > > > Sven >
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