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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 ED1AFC433DF for ; Wed, 17 Jun 2020 03:06:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C57C82082E for ; Wed, 17 Jun 2020 03:06:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="cRtzcfZI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726710AbgFQDGv (ORCPT ); Tue, 16 Jun 2020 23:06:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38492 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbgFQDGv (ORCPT ); Tue, 16 Jun 2020 23:06:51 -0400 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D88BC061573 for ; Tue, 16 Jun 2020 20:06:51 -0700 (PDT) Received: by mail-pf1-x442.google.com with SMTP id b16so407973pfi.13 for ; Tue, 16 Jun 2020 20:06:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=dq2SjmoQupE4U9LhXdo/f9IZ6YV5RooIfJwqe+qSBlg=; b=cRtzcfZIAK/fnCW3uavu1pTWu4tlI6Gez8w4jjX7ksTVmViB2GmyPtbfv4pHB2N0B7 52+2ATk8e+AdXsI+gEvmXN+4fq+8vjqv5o1Q0+Vd0gW34QPnbxztqI7LwNR9biWgAZ+K iouMSgsyC99J7dM0nr1U+0TzVOj6EhcTo2mWN62PK3JzQGIoX4VIrHq49FgsD5+CV6F5 qU4zo67ue4q3ETFJqak0LoXVYaD8bpLC4qjg64CJULa32Hlk6S/kdBQ2e+0k+xTrp5Ap r2l0ZLwk0wBa1V5SVadZXT7AZlW/xY4KUHIACaXXJvCEgsyULxXV6Kpj0/Uv1SEvLz6T rMxw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=dq2SjmoQupE4U9LhXdo/f9IZ6YV5RooIfJwqe+qSBlg=; b=eeeTqr0M/0Qsvv8643Hi4vJrGsdOi/I6A7KPkG8gWh8iCCOVk58Loy19EtsgXlY30M O2Zj+Msi7KoncsO/yf6BqycVu2SSHQhml9FDYiM3HDhA7u7TZBdizHlUtMSSsbY8yh7C Xnh4Ll+dyuCd0eMUUsae3rM00Xc55yeb6ZH+43TqRA//PUqzXuzWhsk/G6dlbgL4Flih ASf3TJRTtX/dRh0e0GDXxexI9BtxP03GxQLGPgQwDp9iXNrZGoz3wJEWVDvYKPzEDWG3 MiM6UddEB2NmazUJ7mPpgQPvcShlZpUJjqMZ0TG6SZeO8s2osp1aMMHfP9cXQ74tp8Op lZWw== X-Gm-Message-State: AOAM532d91S+GKqR2lyw14eQq2PSXtsvefRPQAlxFcNWCCdsnGcWgpa5 faypRh9ZBcjrZKek4Ir5RvY= X-Google-Smtp-Source: ABdhPJw//k0NXcYX0XzZ+Ih/gjrZwd7t+FwVka95iS2KhwMy/vQRUu8NT/fZjBz2+jqHCu7RJ8h7ag== X-Received: by 2002:a63:4822:: with SMTP id v34mr3878745pga.81.1592363210656; Tue, 16 Jun 2020 20:06:50 -0700 (PDT) Received: from jordon-HP-15-Notebook-PC.domain.name ([122.171.213.184]) by smtp.gmail.com with ESMTPSA id g19sm18210446pfo.209.2020.06.16.20.06.47 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Jun 2020 20:06:49 -0700 (PDT) From: Souptick Joarder To: boris.ostrovsky@oracle.com, jgross@suse.com, sstabellini@kernel.org Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, Souptick Joarder , John Hubbard Subject: [RFC PATCH] xen/privcmd: Convert get_user_pages*() to pin_user_pages*() Date: Wed, 17 Jun 2020 08:44:58 +0530 Message-Id: <1592363698-4266-1-git-send-email-jrdr.linux@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In 2019, we introduced pin_user_pages*() and now we are converting get_user_pages*() to the new API as appropriate. [1] & [2] could be referred for more information. [1] Documentation/core-api/pin_user_pages.rst [2] "Explicit pinning of user-space pages": https://lwn.net/Articles/807108/ Signed-off-by: Souptick Joarder Cc: John Hubbard --- Hi, I have compile tested this patch but unable to run-time test, so any testing help is much appriciated. Also have a question, why the existing code is not marking the pages dirty (since it did FOLL_WRITE) ? drivers/xen/privcmd.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index a250d11..543739e 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -594,7 +594,7 @@ static int lock_pages( if (requested > nr_pages) return -ENOSPC; - pinned = get_user_pages_fast( + pinned = pin_user_pages_fast( (unsigned long) kbufs[i].uptr, requested, FOLL_WRITE, pages); if (pinned < 0) @@ -614,10 +614,7 @@ static void unlock_pages(struct page *pages[], unsigned int nr_pages) if (!pages) return; - for (i = 0; i < nr_pages; i++) { - if (pages[i]) - put_page(pages[i]); - } + unpin_user_pages(pages, nr_pages); } static long privcmd_ioctl_dm_op(struct file *file, void __user *udata) -- 1.9.1