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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 7695DC433DF for ; Sun, 17 May 2020 19:46:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5BF2820657 for ; Sun, 17 May 2020 19:46:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726693AbgEQTq2 (ORCPT ); Sun, 17 May 2020 15:46:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbgEQTq2 (ORCPT ); Sun, 17 May 2020 15:46:28 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50998C061A0C; Sun, 17 May 2020 12:46:28 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 0AEF1128A2DB1; Sun, 17 May 2020 12:46:27 -0700 (PDT) Date: Sun, 17 May 2020 12:46:27 -0700 (PDT) Message-Id: <20200517.124627.503340627820837794.davem@davemloft.net> To: jhubbard@nvidia.com Cc: linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org Subject: Re: [PATCH] oradax: convert get_user_pages() --> pin_user_pages() From: David Miller In-Reply-To: <20200517020829.856731-1-jhubbard@nvidia.com> References: <20200517020829.856731-1-jhubbard@nvidia.com> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sun, 17 May 2020 12:46:28 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: John Hubbard Date: Sat, 16 May 2020 19:08:29 -0700 > This code was using get_user_pages_fast(), in a "Case 2" scenario > (DMA/RDMA), using the categorization from [1]. That means that it's > time to convert the get_user_pages_fast() + put_page() calls to > pin_user_pages_fast() + unpin_user_pages() calls. > > There is some helpful background in [2]: basically, this is a small > part of fixing a long-standing disconnect between pinning pages, and > file systems' use of those pages. > > [1] Documentation/core-api/pin_user_pages.rst > > [2] "Explicit pinning of user-space pages": > https://lwn.net/Articles/807108/ > > Cc: David S. Miller > Cc: sparclinux@vger.kernel.org > Signed-off-by: John Hubbard Applied to sparc-next, thanks. From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Date: Sun, 17 May 2020 19:46:27 +0000 Subject: Re: [PATCH] oradax: convert get_user_pages() --> pin_user_pages() Message-Id: <20200517.124627.503340627820837794.davem@davemloft.net> List-Id: References: <20200517020829.856731-1-jhubbard@nvidia.com> In-Reply-To: <20200517020829.856731-1-jhubbard@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: jhubbard@nvidia.com Cc: linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org From: John Hubbard Date: Sat, 16 May 2020 19:08:29 -0700 > This code was using get_user_pages_fast(), in a "Case 2" scenario > (DMA/RDMA), using the categorization from [1]. That means that it's > time to convert the get_user_pages_fast() + put_page() calls to > pin_user_pages_fast() + unpin_user_pages() calls. > > There is some helpful background in [2]: basically, this is a small > part of fixing a long-standing disconnect between pinning pages, and > file systems' use of those pages. > > [1] Documentation/core-api/pin_user_pages.rst > > [2] "Explicit pinning of user-space pages": > https://lwn.net/Articles/807108/ > > Cc: David S. Miller > Cc: sparclinux@vger.kernel.org > Signed-off-by: John Hubbard Applied to sparc-next, thanks.