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Subject: Re: [RFC] mac80211_hwsim: notify user-space about channel change.
From: Johannes Berg <johannes@sipsolutions.net>
To: Ben Greear <greearb@candelatech.com>
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Date: Fri, 17 Apr 2015 13:25:12 +0200
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On Wed, 2015-04-15 at 08:06 -0700, Ben Greear wrote:
[...]
> > The issue is that with your patch in this can't be addressed in
> > follow-on patches as it fixes the userspace API.
> 
> Ok, so adding an additional 'uint16 ctx' to the channel change data,
> and providing a 'type' field that includes start-using, stop-using
> would address this problem adequately?
> 
> Start-using seems it would be the same as change-channel, or do I need
> a type for that as well?

Yeah that seems reasonble. You'd need to store the ctx id in the actual
chanctx struct in hwsim I guess (and unconditionally use 0 for the
non-chanctx case)

I'm not sure we should conflate start-using and change-channel,
userspace might have to set up data structures if it really wants to
track multiple channels, so having a separate start-using might be
easier?

johannes