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=-6.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 4066FC4332D for ; Tue, 19 Jan 2021 11:28:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22CCB22DD3 for ; Tue, 19 Jan 2021 11:28:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391299AbhASLYq (ORCPT ); Tue, 19 Jan 2021 06:24:46 -0500 Received: from support.corp-email.com ([222.73.234.235]:9498 "EHLO support.corp-email.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389130AbhASLJ1 (ORCPT ); Tue, 19 Jan 2021 06:09:27 -0500 Received: from ([183.47.25.45]) by support.corp-email.com ((LNX1044)) with ASMTP (SSL) id NEB00015; Tue, 19 Jan 2021 19:07:15 +0800 Received: from GCY-EXS-15.TCL.com (10.74.128.165) by GCY-EXS-06.TCL.com (10.74.128.156) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Tue, 19 Jan 2021 19:07:16 +0800 Received: from localhost.localdomain (172.16.34.38) by GCY-EXS-15.TCL.com (10.74.128.165) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Tue, 19 Jan 2021 19:07:14 +0800 From: Rokudo Yan To: CC: , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH RESEND V11 0/7] fuse: Add support for passthrough read/write Date: Tue, 19 Jan 2021 19:06:54 +0800 Message-ID: <20210119110654.11817-1-wu-yan@tcl.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210118192748.584213-1-balsini@android.com> References: <20210118192748.584213-1-balsini@android.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [172.16.34.38] X-ClientProxiedBy: GCY-EXS-01.TCL.com (10.74.128.151) To GCY-EXS-15.TCL.com (10.74.128.165) tUid: 2021119190715f9f4f0275f6c87c21aaa38b5cbe9b56e X-Abuse-Reports-To: service@corp-email.com Abuse-Reports-To: service@corp-email.com X-Complaints-To: service@corp-email.com X-Report-Abuse-To: service@corp-email.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org on Mon, Jan 18, 2021 at 5:27 PM Alessio Balsini wrote: > > This is the 11th version of the series, rebased on top of v5.11-rc4. > Please find the changelog at the bottom of this cover letter. > > Add support for file system passthrough read/write of files when enabled > in userspace through the option FUSE_PASSTHROUGH. [...] Hi Allesio, Could you please add support for passthrough mmap too ? If the fuse file opened with passthrough actived, and then map (shared) to (another) process address space using mmap interface. As access the file with mmap will pass the vfs cache of fuse, but access the file with read/write will bypass the vfs cache of fuse, this may cause inconsistency. eg. the reader read the fuse file with mmap() and the writer modify the file with write(), the reader may not see the modification immediately since the writer bypass the vfs cache of fuse. Actually we have already meet an issue caused by the inconsistency after applying fuse passthrough scheme to our product. Thanks, yanwu.