From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753690AbbHGOsg (ORCPT ); Fri, 7 Aug 2015 10:48:36 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:34207 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751581AbbHGOse convert rfc822-to-8bit (ORCPT ); Fri, 7 Aug 2015 10:48:34 -0400 From: Michal Nazarewicz To: Feng Tang , Greg Kroah-Hartman Cc: John Stultz , Andrew Morton , Kyungmin Park , Marek Szyprowski , Joonsoo Kim , LKML Subject: Re: [PATCH v2] staging: ion: Add a default struct device for cma heap In-Reply-To: <20150807064601.GA9338@shbuild888> Organization: http://mina86.com/ References: <1438919413-14440-1-git-send-email-feng.tang@intel.com> <20150807045404.GA26925@kroah.com> <20150807064601.GA9338@shbuild888> User-Agent: Notmuch/0.19+53~g2e63a09 (http://notmuchmail.org) Emacs/25.0.50.1 (x86_64-unknown-linux-gnu) X-Face: PbkBB1w#)bOqd`iCe"Ds{e+!C7`pkC9a|f)Qo^BMQvy\q5x3?vDQJeN(DS?|-^$uMti[3D*#^_Ts"pU$jBQLq~Ud6iNwAw_r_o_4]|JO?]}P_}Nc&"p#D(ZgUb4uCNPe7~a[DbPG0T~!&c.y$Ur,=N4RT>]dNpd;KFrfMCylc}gc??'U2j,!8%xdD Face: 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 X-PGP: 50751FF4 X-PGP-FP: AC1F 5F5C D418 88F8 CC84 5858 2060 4012 5075 1FF4 X-Hashcash: 1:20:150807:m.szyprowski@samsung.com::raAFnCvPmfEwfu5M:00000000000000000000000000000000000000IxC X-Hashcash: 1:20:150807:john.stultz@linaro.org::6dRIqMsErVSrnbJy:0000000000000000000000000000000000000000LtQ X-Hashcash: 1:20:150807:kyungmin.park@samsung.com::ypJIdgzJ+wcVpb2m:0000000000000000000000000000000000002qaT X-Hashcash: 1:20:150807:feng.tang@intel.com::MfupCaxfGMSlTLiM:0000000000000000000000000000000000000000000xG3 X-Hashcash: 1:20:150807:akpm@linux-foundation.org::f0osyCXzwfysL9MN:0000000000000000000000000000000000002mMU X-Hashcash: 1:20:150807:gregkh@linuxfoundation.org::ba9oJMqcyuTJxAWm:0000000000000000000000000000000000042yV X-Hashcash: 1:20:150807:linux-kernel@vger.kernel.org::t1pkEVqiYgdnYwCh:0000000000000000000000000000000006dxk X-Hashcash: 1:20:150807:iamjoonsoo.kim@lge.com::iAG36X+L5S8fmjXi:0000000000000000000000000000000000000007qqA Date: Fri, 07 Aug 2015 16:48:28 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 07 2015, Feng Tang wrote: > As I described above, the dummy struct device is only needed for > dma request, its lifetime is align with the cma_heap itself. Again, this is from perspective of someone who is unfamiliar with ION, but perhaps a viable solution is to bypass DMA API and just call cma_alloc directly? -- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +------ooO--(_)--Ooo--