Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755339Ab3JWBFd (ORCPT ); Tue, 22 Oct 2013 21:05:33 -0400 Received: from mail-qa0-f52.google.com ([209.85.216.52]:39681 "EHLO mail-qa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753998Ab3JWBFc (ORCPT ); Tue, 22 Oct 2013 21:05:32 -0400 MIME-Version: 1.0 In-Reply-To: <20131022231235.GE11192@jonmason-lab> References: <1382117733-16720-12-git-send-email-b.zolnierkie@samsung.com> <20131022210828.31348.41879.stgit@viggo.jf.intel.com> <20131022231235.GE11192@jonmason-lab> Date: Tue, 22 Oct 2013 18:05:31 -0700 X-Google-Sender-Auth: s-VmiiYxzJKnqLl-mK6VeUnWIa4 Message-ID: Subject: Re: [PATCH v2 11/13] NTB: convert to dmaengine_unmap_data From: Dan Williams To: Jon Mason Cc: dmaengine@vger.kernel.org, Dave Jiang , Bartlomiej Zolnierkiewicz , Vinod Koul , Tomasz Figa , "linux-kernel@vger.kernel.org" , Kyungmin Park , Russell King - ARM Linux Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1782 Lines: 45 On Tue, Oct 22, 2013 at 4:12 PM, Jon Mason wrote: > On Tue, Oct 22, 2013 at 02:29:36PM -0700, Dan Williams wrote: >> On Fri, Oct 18, 2013 at 6:06 PM, Jon Mason wrote: >> > On Fri, Oct 18, 2013 at 07:35:31PM +0200, Bartlomiej Zolnierkiewicz wrote: >> >> Use the generic unmap object to unmap dma buffers. >> >> >> >> As NTB can be compiled without DMA_ENGINE support add >> > >> > Seems like the stubs should be added outside of this patch. >> >> I think they are ok here as this is the only driver that uses them. >> The alternative is a new api patch without a user. >> >> > Also, the >> > comment implies that NTB could not be compiled without DMA_ENGINE >> > support before, which it could be. >> >> Hmm, I read it as "since NTB *can* be compiled without dmaengine here >> are some stubs". > > This poses an overall question of whether it would simply be better to > abstract all of the with/without DMA_ENGINE part and simply remap it > to memcpy if DMA_ENGINE is not set (or if the DMA engine is > hotplugged). Of course, this is outside the scope of this patch. That's at least the promise of async_memcpy() it does not care if a channel is there or not, but I think it is better if the client has a strict dma and non-dma path. Hiding the dma details from the client seems to have been the wrong choice at least for raid. > That is fine. It can be like this in the short term. > > Thanks, > Jon I'll take that as: Acked-by: Jon Mason ...but holler if not. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/