Actually, as long as there is no "struct page" there _are_ problems.
This is why the NUMA stuff was brought up - it would require that there
be a mem_map for the PCI pages.. (to do ref-counting etc).
>But could someone explain me one thing. Does bus-mastering
>from io really work? And if it does, is it enough fast?
>At least, looking at my book on pci, I do not understand
>how such transfers are able to use bursts. MRM is banned for them...
It does work at least on some hardware. But no, I don't think you can
depend on bursting (but I don't see why it couldn't work in theory).
Linus
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