From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755204AbbFQLdj (ORCPT ); Wed, 17 Jun 2015 07:33:39 -0400 Received: from down.free-electrons.com ([37.187.137.238]:56721 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752948AbbFQLd3 (ORCPT ); Wed, 17 Jun 2015 07:33:29 -0400 Date: Wed, 17 Jun 2015 13:33:24 +0200 From: Boris Brezillon To: Herbert Xu Cc: "David S. Miller" , linux-crypto@vger.kernel.org, Arnaud Ebalard , Tawfik Bayouk , Lior Amsalem , Nadav Haklai , Eran Ben-Avi , Thomas Petazzoni , Gregory CLEMENT , Jason Cooper , Sebastian Hesselbarth , Andrew Lunn , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Jason Gunthorpe , Imre Kaloz Subject: Re: [PATCH v6 05/14] crypto: marvell/CESA: add TDMA support Message-ID: <20150617133324.1ee6ad55@bbrezillon> In-Reply-To: <20150617095001.GA11538@gondor.apana.org.au> References: <1434527142-3609-1-git-send-email-boris.brezillon@free-electrons.com> <1434527142-3609-6-git-send-email-boris.brezillon@free-electrons.com> <20150617095001.GA11538@gondor.apana.org.au> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 17 Jun 2015 17:50:01 +0800 Herbert Xu wrote: > On Wed, Jun 17, 2015 at 09:45:33AM +0200, Boris Brezillon wrote: > > > > + ret = dma_map_sg(cesa_dev->dev, req->src, creq->src_nents, > > + DMA_TO_DEVICE); > > + if (!ret) > > + return -ENOMEM; > > + > > + creq->src_nents = ret; > > DMA-API-HOWTO says that you must retain the original nents and > use it when you call dma_unmap_sg. So I'm afraid one more repost > is needed :) My bad (again :-/). Actually, I think I don't need to save the dma_map_sg return val, since I'm using the sg_next function to iterate over the scatterlist. Am I right ? IOW, is the ->map_sg() function (in dma_map_ops) supposed to merge the contiguous entries and then flag the unused entries with the is_chain flag ? If that's not the case, and the ->map_sg() just marks the merged entries as empty (length = 0), then I'll have to rework my iterator algorithm. -- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com From mboxrd@z Thu Jan 1 00:00:00 1970 From: boris.brezillon@free-electrons.com (Boris Brezillon) Date: Wed, 17 Jun 2015 13:33:24 +0200 Subject: [PATCH v6 05/14] crypto: marvell/CESA: add TDMA support In-Reply-To: <20150617095001.GA11538@gondor.apana.org.au> References: <1434527142-3609-1-git-send-email-boris.brezillon@free-electrons.com> <1434527142-3609-6-git-send-email-boris.brezillon@free-electrons.com> <20150617095001.GA11538@gondor.apana.org.au> Message-ID: <20150617133324.1ee6ad55@bbrezillon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, 17 Jun 2015 17:50:01 +0800 Herbert Xu wrote: > On Wed, Jun 17, 2015 at 09:45:33AM +0200, Boris Brezillon wrote: > > > > + ret = dma_map_sg(cesa_dev->dev, req->src, creq->src_nents, > > + DMA_TO_DEVICE); > > + if (!ret) > > + return -ENOMEM; > > + > > + creq->src_nents = ret; > > DMA-API-HOWTO says that you must retain the original nents and > use it when you call dma_unmap_sg. So I'm afraid one more repost > is needed :) My bad (again :-/). Actually, I think I don't need to save the dma_map_sg return val, since I'm using the sg_next function to iterate over the scatterlist. Am I right ? IOW, is the ->map_sg() function (in dma_map_ops) supposed to merge the contiguous entries and then flag the unused entries with the is_chain flag ? If that's not the case, and the ->map_sg() just marks the merged entries as empty (length = 0), then I'll have to rework my iterator algorithm. -- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com