From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from s3.sipsolutions.net ([144.76.43.152]:49636 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932628AbaEGLyW (ORCPT ); Wed, 7 May 2014 07:54:22 -0400 Message-ID: <1399463646.10517.28.camel@jlt4.sipsolutions.net> (sfid-20140507_135425_948546_B1C41B60) Subject: Re: [PATCH v5] mac80211: implement multi-vif in-place reservations From: Johannes Berg To: Michal Kazior Cc: Luca Coelho , linux-wireless , Simon Wunderlich Date: Wed, 07 May 2014 13:54:06 +0200 In-Reply-To: (sfid-20140507_131912_954267_EF512364) References: <1397050174-26121-14-git-send-email-michal.kazior@tieto.com> <1398849681-3606-1-git-send-email-michal.kazior@tieto.com> <1399372915.4218.17.camel@jlt4.sipsolutions.net> <1399385141.4218.37.camel@jlt4.sipsolutions.net> <1399450061.5038.10.camel@jlt4.sipsolutions.net> <1399455657.6800.4.camel@dubbel> <1399457760.6800.7.camel@dubbel> <1399460964.10517.12.camel@jlt4.sipsolutions.net> (sfid-20140507_131912_954267_EF512364) Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2014-05-07 at 13:19 +0200, Michal Kazior wrote: > On 7 May 2014 13:09, Johannes Berg wrote: > > On Wed, 2014-05-07 at 12:38 +0200, Michal Kazior wrote: > > > >> I was actually thinking of just providing the bare minimum to fulfill > >> requirements for the CSA case: int foo(*hw, **vifs, n_vifs, *oldctx, > >> *newctx, flags). > >> > >> Having an array of transactions passed through a single call seems > >> more robust and cleaner. Naiive drivers might just iterate over each > >> entry while more complex drivers might examine the whole request and > >> detect chanctx swapping. > > > > Not sure what you mean by "detect chanctx swapping" - the flags would > > indicate that anyway, no? In any case, I like this better than a more > > general transaction API I think, it's easier for the driver > > implementation and clearer as to what needs to be done/supported. > > You could submit a transaction sequence: > - new chanctx2 > - switch vif1 chanctx1->chanctx2 > - switch vif2 chanctx1->chanctx2 > - remove chanctx1 Well, you don't really have any other choice with the API you proposed, and IMHO that's a good thing. The only possibilities that can be expressed with that would seem to be: 1) for_each_vif: switch vif from oldctx to newctx 2) add newctx for_each_vif: switch vif from oldctx to newctx del oldctx With the option between 1/2 being selected by the flags. I don't see what the driver has to infer about it being a channel switch - it necessarily is one, no? johannes