From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751664AbbHELP6 (ORCPT ); Wed, 5 Aug 2015 07:15:58 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:35759 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751191AbbHELP4 convert rfc822-to-8bit (ORCPT ); Wed, 5 Aug 2015 07:15:56 -0400 From: Michal Nazarewicz To: Feng Tang Cc: "linux-kernel\@vger.kernel.org" , "m.szyprowski\@samsung.com" , "kyungmin.park\@samsung.com" , "akpm\@linux-foundation.org" , "iamjoonsoo.kim\@lge.com" , "john.stultz\@linaro.org" Subject: Re: [PATCH] CMA: Don't return a valid cma for non-cma dev In-Reply-To: <20150805105558.GA8875@shbuild888> Organization: http://mina86.com/ References: <1438223828-26140-1-git-send-email-feng.tang@intel.com> <1438311070.4299.1.camel@intel.com> <20150731151816.GA18347@shbuild888> <20150805091917.GA27241@shbuild888> <20150805105558.GA8875@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: 1:20:150805:iamjoonsoo.kim@lge.com::pLZ6NwlMVTw7mSNL:0000000000000000000000000000000000000000Rwc X-Hashcash: 1:20:150805:linux-kernel@vger.kernel.org::g12/mkV6lolfh4Iq:0000000000000000000000000000000000dNS X-Hashcash: 1:20:150805:feng.tang@intel.com::jJFF+623s2hvbEY9:0000000000000000000000000000000000000000000zfx X-Hashcash: 1:20:150805:m.szyprowski@samsung.com::rFnFv6fZQoLcPCtg:000000000000000000000000000000000000019w3 X-Hashcash: 1:20:150805:akpm@linux-foundation.org::/c6RFXenu5UdxSsb:0000000000000000000000000000000000002jMM X-Hashcash: 1:20:150805:john.stultz@linaro.org::bCKB8ujuV2LqSz3H:00000000000000000000000000000000000000038Gf X-Hashcash: 1:20:150805:kyungmin.park@samsung.com::fbp0A4P/GjMxgXGf:000000000000000000000000000000000000AeIm Date: Wed, 05 Aug 2015 13:15:50 +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 Wed, Aug 05, 2015 at 12:28:03PM +0200, Michal Nazarewicz wrote: >> If you need several CMA areas to allocate from, create multiple struct >> devices. On Wed, Aug 05 2015, Feng Tang wrote: > I've made a quick patch, which works ok on our multiple cma heap cases. > --- > diff --git a/drivers/staging/android/ion/ion_cma_heap.c b/drivers/staging/android/ion/ion_cma_heap.c > index f4211f1..ee9c5d1 100644 > --- a/drivers/staging/android/ion/ion_cma_heap.c > +++ b/drivers/staging/android/ion/ion_cma_heap.c > @@ -29,6 +29,7 @@ > struct ion_cma_heap { > struct ion_heap heap; > struct device *dev; > + struct device default_dma_dev; I’m unfamiliar with ION code so cannot comment in great detail, butwhy do you need dev and default_dma_dev fields? Just make dev a non-pointer and use that. > }; > > #define to_cma_heap(x) container_of(x, struct ion_cma_heap, heap) > @@ -180,9 +181,14 @@ struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *data) > return ERR_PTR(-ENOMEM); > > cma_heap->heap.ops = &ion_cma_ops; > - /* get device from private heaps data, later it will be > - * used to make the link with reserved CMA memory */ > - cma_heap->dev = data->priv; > + > + cma_heap->dev = &cma_heap->default_dma_dev; > + cma_heap->dev->coherent_dma_mask = DMA_BIT_MASK(32); > + cma_heap->dev->dma_mask = &dev->coherent_dma_mask; > + > + /* data->priv contains a pointer to struct cma */ > + dev_set_cma_area(cma_heap->dev, data->priv); In the previous code, data->priv seemed to be struct device*, but in this code it is used as struct cma*. > + > cma_heap->heap.type = ION_HEAP_TYPE_DMA; > return &cma_heap->heap; > } But yeah, in general, from CMA’s point of view, this looks good. -- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +------ooO--(_)--Ooo--