Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751897AbcDTTOl (ORCPT ); Wed, 20 Apr 2016 15:14:41 -0400 Received: from mail.fireflyinternet.com ([87.106.93.118]:61352 "EHLO fireflyinternet.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750767AbcDTTOi (ORCPT ); Wed, 20 Apr 2016 15:14:38 -0400 X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Date: Wed, 20 Apr 2016 20:14:32 +0100 From: Chris Wilson To: "Luis R. Rodriguez" Cc: intel-gfx@lists.freedesktop.org, Tvrtko Ursulin , Mika Kuoppala , Joonas Lahtinen , Tvrtko Ursulin , Daniel Vetter , Jani Nikula , David Airlie , Yishai Hadas , Dan Williams , Ingo Molnar , "Peter Zijlstra (Intel)" , David Hildenbrand , dri-devel@lists.freedesktop.org, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 02/19] io-mapping: Specify mapping size for io_mapping_map_wc() Message-ID: <20160420191432.GK17454@nuc-i3427.alporthouse.com> Mail-Followup-To: Chris Wilson , "Luis R. Rodriguez" , intel-gfx@lists.freedesktop.org, Tvrtko Ursulin , Mika Kuoppala , Joonas Lahtinen , Tvrtko Ursulin , Daniel Vetter , Jani Nikula , David Airlie , Yishai Hadas , Dan Williams , Ingo Molnar , "Peter Zijlstra (Intel)" , David Hildenbrand , dri-devel@lists.freedesktop.org, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org References: <1461177750-20187-1-git-send-email-chris@chris-wilson.co.uk> <1461177750-20187-3-git-send-email-chris@chris-wilson.co.uk> <20160420185844.GQ1990@wotan.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160420185844.GQ1990@wotan.suse.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1843 Lines: 41 On Wed, Apr 20, 2016 at 08:58:44PM +0200, Luis R. Rodriguez wrote: > On Wed, Apr 20, 2016 at 07:42:13PM +0100, Chris Wilson wrote: > > The ioremap() hidden behind the io_mapping_map_wc() convenience helper > > can be used for remapping multiple pages. Extend the helper so that > > future callers can use it for larger ranges. > > > > Signed-off-by: Chris Wilson > > Cc: Tvrtko Ursulin > > Cc: Daniel Vetter > > Cc: Jani Nikula > > Cc: David Airlie > > Cc: Yishai Hadas > > Cc: Dan Williams > > Cc: Ingo Molnar > > Cc: "Peter Zijlstra (Intel)" > > Cc: David Hildenbrand > > Cc: Luis R. Rodriguez > > Cc: intel-gfx@lists.freedesktop.org > > Cc: dri-devel@lists.freedesktop.org > > Cc: netdev@vger.kernel.org > > Cc: linux-rdma@vger.kernel.org > > Cc: linux-kernel@vger.kernel.org > > We have 2 callers today, in the future, can you envision > this API getting more options? If so, in order to avoid the > pain of collateral evolutions I can suggest a descriptor > being passed with the required settings / options. This lets > you evolve the API without needing to go in and modify > old users. If you choose not to that's fine too, just > figured I'd chime in with that as I've seen the pain > with other APIs, and I'm putting an end to the needless > set of collateral evolutions this way. Do you have a good example in mind? I've one more patch to try and take advantage of the io-mapping (that may or not be such a good idea in practice) but I may as well see if I can make io_mapping more useful when I do. -Chris -- Chris Wilson, Intel Open Source Technology Centre