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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 BE368C7618F for ; Mon, 22 Jul 2019 18:53:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 932622190D for ; Mon, 22 Jul 2019 18:53:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="HArRmCgk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730831AbfGVSx4 (ORCPT ); Mon, 22 Jul 2019 14:53:56 -0400 Received: from hqemgate16.nvidia.com ([216.228.121.65]:3507 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727821AbfGVSx4 (ORCPT ); Mon, 22 Jul 2019 14:53:56 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Mon, 22 Jul 2019 11:53:52 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Mon, 22 Jul 2019 11:53:55 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Mon, 22 Jul 2019 11:53:55 -0700 Received: from [10.110.48.28] (10.124.1.5) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Mon, 22 Jul 2019 18:53:54 +0000 Subject: Re: [PATCH 1/3] drivers/gpu/drm/via: convert put_page() to put_user_page*() To: Christoph Hellwig , CC: Andrew Morton , Alexander Viro , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Boaz Harrosh , Daniel Vetter , Dan Williams , Dave Chinner , David Airlie , "David S . Miller" , Ilya Dryomov , Jan Kara , Jason Gunthorpe , Jens Axboe , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Johannes Thumshirn , Magnus Karlsson , Matthew Wilcox , Miklos Szeredi , Ming Lei , Sage Weil , Santosh Shilimkar , Yan Zheng , , , , , , LKML References: <20190722043012.22945-1-jhubbard@nvidia.com> <20190722043012.22945-2-jhubbard@nvidia.com> <20190722093355.GB29538@lst.de> X-Nvconfidentiality: public From: John Hubbard Message-ID: <397ff3e4-e857-037a-1aee-ff6242e024b2@nvidia.com> Date: Mon, 22 Jul 2019 11:53:54 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190722093355.GB29538@lst.de> X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL101.nvidia.com (172.20.187.10) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1563821632; bh=dVEAb2CGI+Rcq3kPxf1ySX9mPnHE1aqM1bmhIjbORUc=; h=X-PGP-Universal:Subject:To:CC:References:X-Nvconfidentiality:From: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=HArRmCgkrni3Mv1zhHNTOrkORst1xu/RkKpSHN9NJ6eHvsCKnyilmR14o7Vu/72+2 KzGoGeJ5LPaTaA997Z1lTeEX5TN0QxgL9zU0E1stVph1kaJP/CjI3G/fZC7Su8uSDP zQdMp40Hd3vz1tqkE44dAhr5RuD9olYTaUe61D28D1sEpt/q0j8DDbdv6B2ii7KaIW 3XKa/T3Q4mkn6zgOvtasGsucgAaQQ3F4SWgLkmtCnVrJI8UW8FhQBhBRF+eCjxAZDo DjdQKgIytgBgEr6BmAqoJ/KeCGoQ826d60sYBB87S4A1fHrwdDnuUDjUmWCd/fqdhR fU5s088Wpq8BA== Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On 7/22/19 2:33 AM, Christoph Hellwig wrote: > On Sun, Jul 21, 2019 at 09:30:10PM -0700, john.hubbard@gmail.com wrote: >> for (i = 0; i < vsg->num_pages; ++i) { >> if (NULL != (page = vsg->pages[i])) { >> if (!PageReserved(page) && (DMA_FROM_DEVICE == vsg->direction)) >> - SetPageDirty(page); >> - put_page(page); >> + put_user_pages_dirty(&page, 1); >> + else >> + put_user_page(page); >> } > > Can't just pass a dirty argument to put_user_pages? Also do we really Yes, and in fact that would help a lot more than the single page case, which is really just cosmetic after all. > need a separate put_user_page for the single page case? > put_user_pages_dirty? Not really. I'm still zeroing in on the ideal API for all these call sites, and I agree that the approach below is cleaner. > > Also the PageReserved check looks bogus, as I can't see how a reserved > page can end up here. So IMHO the above snippled should really look > something like this: > > put_user_pages(vsg->pages[i], vsg->num_pages, > vsg->direction == DMA_FROM_DEVICE); > > in the end. > Agreed. thanks, -- John Hubbard NVIDIA