From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E940C4320A for ; Tue, 24 Aug 2021 19:39:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 231BA61220 for ; Tue, 24 Aug 2021 19:39:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234921AbhHXTkD (ORCPT ); Tue, 24 Aug 2021 15:40:03 -0400 Received: from smtp12.smtpout.orange.fr ([80.12.242.134]:38617 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234649AbhHXTj7 (ORCPT ); Tue, 24 Aug 2021 15:39:59 -0400 Received: from [192.168.1.18] ([90.126.253.178]) by mwinf5d35 with ME id lXfC2500Q3riaq203XfC8y; Tue, 24 Aug 2021 21:39:13 +0200 X-ME-Helo: [192.168.1.18] X-ME-Auth: Y2hyaXN0b3BoZS5qYWlsbGV0QHdhbmFkb28uZnI= X-ME-Date: Tue, 24 Aug 2021 21:39:13 +0200 X-ME-IP: 90.126.253.178 Subject: Re: [PATCH] parisc/parport_gsc: switch from 'pci_' to 'dma_' API To: Robin Murphy , James.Bottomley@HansenPartnership.com, deller@gmx.de, sudipm.mukherjee@gmail.com, sumit.semwal@linaro.org, christian.koenig@amd.com Cc: linux-parisc@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org References: <93b21629db55629ec3d384e8184c4a9dd0270c11.1629754126.git.christophe.jaillet@wanadoo.fr> <1a6f5b12-7cf2-cdb8-7a60-20c2d2ee38f3@arm.com> From: Christophe JAILLET Message-ID: Date: Tue, 24 Aug 2021 21:39:12 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <1a6f5b12-7cf2-cdb8-7a60-20c2d2ee38f3@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org Le 24/08/2021 à 12:24, Robin Murphy a écrit : > On 2021-08-23 22:30, Christophe JAILLET wrote: >> The wrappers in include/linux/pci-dma-compat.h should go away. >> >> The patch has been generated with the coccinelle script below. >> >> @@ >> expression e1, e2, e3, e4; >> @@ >> -    pci_free_consistent(e1, e2, e3, e4) >> +    dma_free_coherent(&e1->dev, e2, e3, e4) >> >> Signed-off-by: Christophe JAILLET >> --- >> If needed, see post from Christoph Hellwig on the kernel-janitors ML: >>     https://marc.info/?l=kernel-janitors&m=158745678307186&w=4 >> >> This has *NOT* been compile tested because I don't have the needed >> configuration. >> ssdfs >> --- >>   drivers/parport/parport_gsc.c | 5 ++--- >>   1 file changed, 2 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/parport/parport_gsc.c >> b/drivers/parport/parport_gsc.c >> index 1e43b3f399a8..db912fa6b6df 100644 >> --- a/drivers/parport/parport_gsc.c >> +++ b/drivers/parport/parport_gsc.c >> @@ -390,9 +390,8 @@ static int __exit parport_remove_chip(struct >> parisc_device *dev) >>           if (p->irq != PARPORT_IRQ_NONE) >>               free_irq(p->irq, p); >>           if (priv->dma_buf) >> -            pci_free_consistent(priv->dev, PAGE_SIZE, >> -                        priv->dma_buf, >> -                        priv->dma_handle); >> +            dma_free_coherent(&priv->dev->dev, PAGE_SIZE, >> +                      priv->dma_buf, priv->dma_handle); > > Hmm, seeing a free on its own made me wonder where the corresponding > alloc was, but on closer inspection it seems there isn't one. AFAICS > priv->dma_buf is only ever assigned with NULL (and priv->dev doesn't > seem to be assigned at all), so this could likely just be removed. In > fact it looks like all the references to DMA in this driver are just > copy-paste from parport_pc and unused. > > Robin. > Agreed. I had the same reaction, but as the patch should basically be a no-op, it looked safe, even if non-optimal. Looking at parport_gsc_private, pword, readIntrThreshold and writeIntrThreshold also look unused. My own goal is to remove the 'pci_free_consistent()' call in order to remove a deprecated API. As said, I can not compile this driver. I could send a blind fix that axes 'pci_free_consistent()' and remove some fields in parport_gsc_private, but I'm not sure that it is the best way to go. Do you prefer to look at it by yourself or do you prefer to compile test my trials? CJ >>           kfree (p->private_data); >>           parport_put_port(p); >>           kfree (ops); /* hope no-one cached it */ >> >