On Thu, 2018-08-23 at 07:24 +0200, Christoph Hellwig wrote: > > Well, iommus can have bypass regions, which we also use for > > performance, so we do at dma_set_mask() time "swap" the ops around, and > > in that case, we do want to check the mask against the actual top of > > memory... > > That is a bit of a powerpc special case (we also had one other arch > doing that, but it got removed in the great purge, can't rember which > one right now). Everyone else has one set of ops, and they just switch > to the direct mapping inside the iommu ops.
We more or less do that too in some of ours these days bcs of the whole coherent_mask vs mask where a given device might need either depending on the type of mapping. Ben. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
