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Please > > lets not push a private interconnect address through the scatterlist > > dma_addr_t! > > I think that needs to be defined per interconnect, choosing a data > structure that suits best. Although I find it reasonable to mandate > dma_addr_t or scatterlists to *not* be used. Can you include some sketch of how that would look? And cc me please on future versions :) > > Assuming that you imagine we'd define some global well known > > interconnect > > > > 'struct blah pci_bar_interconnect {..}' > > > > And if that is negotiated then the non-scatterlist communication > > would > > give the (struct pci_dev *, bar index, bar offset) list? > > Yes something like that. Although I think perhaps the dev + bar index > might be part of the negotiation, so that it is rejected if the > importer feels that there is no implied PF + VF interconnect. Then the > list would be reduced to only the offset. I'm also happy if the list is just a list of bar offsets for a single bar and the pci_dev/bar index is discovered by the importer before getting the list. That's probably a better API design anyhow since building the list just to check the pci_dev is wasteful. In this case a simple vmap of bar offset / len pairs would be nice and easy place to start. Jason