PCI Arbiter status

[Joan Lledó]

Hello Hurd,

Now I've finished porting lwip 2.1.2, I'd like to work on the pci
arbiter again.

Before starting to work, I'd like to know the current status of the
arbiter. I've been taking a look at the old mails, please tell me if
I'm wrong:

1- If I understood it right, the translator no longer accesses the pci
port directly, it uses libpciaccess instead, right? so, for a driver in
netdde that wants to access the bus, the big pictures is this:

        netdde -> libpciaccess -> arbiter -> libpciaccess -> hardware

Am I right? How does libpciaccess know when it's being used by the
arbiter and when by a user task?

2- About the patch [1], I haven't read it thoroughly, but it includes
the changes to make the arbiter use libpciaccess instead of probing the
bus directly. But I don't see the code commited in hurd's upstream, is
it because nobody reviewed it, or is there some problem?

3- In libpciaccess upstream there are some commits by Damien Zammit,
one of them with the new modules for the Hurd. I wonder: this new
module expects to be used from both user tasks and the translator?

4- About pciutils, is something ours in upstream? Damien, did you send
patches to pciutils?

5- The TODO in the pci-arbiter folder includes this entry:

        - pci_get_ndevs should be deprecated, applications shouldn't 
          be relying on this

Is this the only change you guys think it should be done in the
interface? Are the other operations OK for you?

6- What do you think is the priority? I'd say it's this:
        1- Define and implement the changes in the interface.
        2- Try to make the modules upstream
        3- Make the arbiter a memory pager
        4- Make netdde non-root

Any thoughts?

Joan

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[1] https://lists.gnu.org/archive/html/bug-hurd/2018-11/msg00033.html