Thank you for your reply, and I am very pleasant to talk with you. ^^
But english is not mother tongue, so I am little confused about your
sentence.
> The O_DIRECT I/O handling
> needs to know about stuff like page reference counts that PCI space
> doesn't have lots of older (and some current) hardware has real problems
> with PCI PCI transfers.
At above sentence, you mean that
'To handle O_DIRECT I/O, stuff like page reference is needed.
But some HW(expecially old HW) doesn't have PCI space,
so that it needs much additional work to add a PCI-PCI transferring.'
Do I understand right?
Please reply, thanks.
> So its a non trivial project, although doable