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=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 4E9C4C4338F for ; Tue, 10 Aug 2021 18:56:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2D85660F35 for ; Tue, 10 Aug 2021 18:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231933AbhHJS4e (ORCPT ); Tue, 10 Aug 2021 14:56:34 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:55206 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231295AbhHJS4d (ORCPT ); Tue, 10 Aug 2021 14:56:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628621770; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aeyIMXFzQ8OzGR9pMLrY5l1FOe7kguJjNVeE5rzOXJQ=; b=FEWTuyihFbSiguWdpPCkaQ75LSo3br9Spv3bsUtewCwqkekLZlyQYfMR1ZWAXjSz9NXWep RMQDpO7kMp4Xgs6flribw+JCtpCglMYFWeH0X6kGWC7MuKDNwcRgzP5tmn0vGBO+jQ6tHY ZwaIh4BaMeUjomgaN9Z47pUOFcpa5Fw= Received: from mail-qk1-f200.google.com (mail-qk1-f200.google.com [209.85.222.200]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-500-EIOAU9_XPliQTOielWiq2g-1; Tue, 10 Aug 2021 14:56:09 -0400 X-MC-Unique: EIOAU9_XPliQTOielWiq2g-1 Received: by mail-qk1-f200.google.com with SMTP id d20-20020a05620a1414b02903d24f3e6540so3280642qkj.7 for ; Tue, 10 Aug 2021 11:56:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=aeyIMXFzQ8OzGR9pMLrY5l1FOe7kguJjNVeE5rzOXJQ=; b=kW4Rbl4k6v12tvyTEXAKLUJ5iYzBmfpIzvOMrV/lJ5occ1UKi4pM3zJoZelaWxRriQ IBJmJ0ziUnFtZXo2RdQOATzV7/wdEpxYF638+Puj9+0XDfcQTLSrjK9ALS13uu0Qs102 HZz+RosmQLaC8+IqfqjD37omAa7Y6J/7jdOECEeXxm65E0noIX5CprycKeLXd23nROZD C+Lb7RmEfe6zp2nOijG9wgqDZktZB1Rcb5zjTdkwrhb4ZrVa8mTV3zkkCPnxI1BkviQc e7H0xbFpXWJe3k1HupWv+mpztAI8dqTStftBuEoE9RXIC5YRWNtj5POdcj2XrSGjlm/f 939Q== X-Gm-Message-State: AOAM5315l3sftpfaPh3WGbJuZ45qEK7Za5Ee1Sbgh9NHJtz6rwG7wHLu NvwqK4UPtNkuA9kHoR7XqT1nvCr6rI4s8vmQbsN30s5/mqRPDWsvqUZd8xN+AVyTR0G8mS4jgsm MIQpjd9L1Ega5 X-Received: by 2002:ad4:4801:: with SMTP id g1mr19233070qvy.34.1628621769275; Tue, 10 Aug 2021 11:56:09 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyY/8eH8qraAlg3QzXb5kdVEZIVe5XqgOyT/w9ICdKgY1ZKVgnUtZNKNx1/TkE7BD326QwTlw== X-Received: by 2002:ad4:4801:: with SMTP id g1mr19233063qvy.34.1628621769108; Tue, 10 Aug 2021 11:56:09 -0700 (PDT) Received: from t490s (bras-base-toroon474qw-grc-92-76-70-75-133.dsl.bell.ca. [76.70.75.133]) by smtp.gmail.com with ESMTPSA id x125sm11300960qkd.8.2021.08.10.11.56.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Aug 2021 11:56:08 -0700 (PDT) Date: Tue, 10 Aug 2021 14:56:07 -0400 From: Peter Xu To: Alex Williamson Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, jgg@nvidia.com Subject: Re: [PATCH 2/7] vfio: Export unmap_mapping_range() wrapper Message-ID: References: <162818167535.1511194.6614962507750594786.stgit@omen> <162818324222.1511194.15934590640437021149.stgit@omen> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <162818324222.1511194.15934590640437021149.stgit@omen> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Aug 05, 2021 at 11:07:22AM -0600, Alex Williamson wrote: > +void vfio_device_unmap_mapping_range(struct vfio_device *device, > + loff_t start, loff_t len) > +{ > + unmap_mapping_range(device->inode->i_mapping, start, len, true); (not a big deal, but still raise this up) It seems to me VFIO MMIO regions do not allow private maps, so even_cow==true should be the same with even_cow==false. even_cow==true will just check the page mapping for each pte even though they should just all match, imho, so logically "false" should work the same and should be tiny-little faster. Thanks, > +} > +EXPORT_SYMBOL_GPL(vfio_device_unmap_mapping_range); -- Peter Xu