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Date: 24 Mar 2014 17:19:41 +0000
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From: "Mark Delany" <c2h@romeo.emu.st>
To: freebsd-net@freebsd.org
Subject: Re: How to make netmap NS_FORWARD work with NR_REG_ONE_NIC?
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> > While good for performance, it unfortunately appears that NS_FORWARD
> > does not work in this mode - presumably because NR_REG_ONE_NIC doesn't
> > include the host ring.
> >
> 
> correct, this is not a supported mode at the moment.
> If you want to implement it you should do it into netmap_poll()
> and create another constant NS_REG_ONE_NIC_SW for the new mode.

Thanks for the clarification. Unfortunately I don't think my skills
are up to hacking features into the netmap module. Is my best
user-space alternative much as I described?

> > Do I have to register an independent handler with NR_REG_SW_NIC and
> > have the h/w ring handlers synchronize with it? If so, I also presume
> > the NR_REG_SW_NIC handler has to manage transfers in both directions,
> > yes?

Or is there a better way in user space?


Mark.