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=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, 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 AD230C64E75 for ; Tue, 17 Nov 2020 18:03:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 635FF2465E for ; Tue, 17 Nov 2020 18:03:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mo+DUXan" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730549AbgKQSDc (ORCPT ); Tue, 17 Nov 2020 13:03:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730547AbgKQSDb (ORCPT ); Tue, 17 Nov 2020 13:03:31 -0500 Received: from mail-io1-xd41.google.com (mail-io1-xd41.google.com [IPv6:2607:f8b0:4864:20::d41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 32B61C0613CF; Tue, 17 Nov 2020 10:03:30 -0800 (PST) Received: by mail-io1-xd41.google.com with SMTP id i9so52187ioo.2; Tue, 17 Nov 2020 10:03:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=L0CqvNmDjkfC8Y294jJfpN5mwqIiGNj8Z0f3z4VcsnM=; b=mo+DUXan4/NPsyiBMtLoIb7YkY1RigFMBP24/GTQaPmS2DVmTw9LMG9zWorlM6joes Cvmw+H7SV/o8XtABoNB00V2Q9eHRhzytvX4kNkO/mBC3XUAE8yfAjED2gHESBtWlxXyA pc2zxgcdvYK6uNicfPCkNyRqdiZ+1FdEAVv/KclYaNNUJyXMOOCO4d0IE/dc2IU+xK9h r+/QRch1hplkC+i6416L14+3V/r0P7mVJMLzGSbDA3cfLvVi1vrgxOAmT51nKCC8gOFo lY00/+q1Ap6nzBvLBoEGgrJc75mzn5hloYWgouwpvANQ/upJwNeVexb90rC36mBRSJQx a6Cw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=L0CqvNmDjkfC8Y294jJfpN5mwqIiGNj8Z0f3z4VcsnM=; b=fQwo0OviIC/ILX/lLlP+r1q3EXr4x2ltWF0VAHgUT9HeC3ojDPYITlA3+gnB4kObqu BoUwGGBp9FPeUPaqfKVA/UkaMO5NkUjWVK9rxCK5jCq7oYY2FSg+drEvDXX2H+QY2zai Rh1cYhOW/XJbnbOqEy2C0dUrEgXtyCzVVqlPqRaUXDS7Awrt1Ew6e/XAcnQXETejstzI grSnrBoADw2CPpnhqtzr+mjXDDZhTF0ABe4bqBOmSbatu6hG4+Nqco/7vt/YWbfyeiHS k5q/S735svmQUjte1ARRJcfPISi4IGJwlsugZVmMnc1j4VeTiIk0UhwAbiZyhmNoMsHQ VGlQ== X-Gm-Message-State: AOAM532SdHiCOPAOBFQEBmAZQ0SycrvYV5FoRY+jN2tUrSLq5Tt2Du5d X0kJYQ2etxQZqW8dSbD2nq+QvSHzyu83QhsZA8k= X-Google-Smtp-Source: ABdhPJyIxEcVNbt4Syb1MkHH0Q8xZk1+KQQfIQw5hhEkaMgHcQxy0JGjYFDwQzvV3AuAlLevrQ/6IgJFGk5vtgu18Co= X-Received: by 2002:a05:6602:5de:: with SMTP id w30mr12240327iox.64.1605636209512; Tue, 17 Nov 2020 10:03:29 -0800 (PST) MIME-Version: 1.0 References: <20201116045758.21774-1-sargun@sargun.me> <20201116045758.21774-4-sargun@sargun.me> <20201116144240.GA9190@redhat.com> <20201116163615.GA17680@redhat.com> <20201116210950.GD9190@redhat.com> <20201117144857.GA78221@redhat.com> <20201117164600.GC78221@redhat.com> In-Reply-To: <20201117164600.GC78221@redhat.com> From: Amir Goldstein Date: Tue, 17 Nov 2020 20:03:16 +0200 Message-ID: Subject: Re: [RFC PATCH 3/3] overlay: Add the ability to remount volatile directories when safe To: Vivek Goyal Cc: Sargun Dhillon , overlayfs , Miklos Szeredi , Alexander Viro , Giuseppe Scrivano , Daniel J Walsh , David Howells , linux-fsdevel , Chengguang Xu Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org > > C. "shutdown" the filesystem if writeback errors happened and return > > EIO from any read, like some blockdev filesystems will do in face > > of metadata write errors > > > > I happen to have a branch ready for that ;-) > > https://github.com/amir73il/linux/commits/ovl-shutdown > > > This branch seems to implement shutdown ioctl. So it will still need > glue code to detect writeback failure in upper/ and trigger shutdown > internally? > Yes. ovl_get_acess() can check both the administrative ofs->goingdown command and the upper writeback error condition for volatile ovl or something like that. > And if that works, then Sargun's patches can fit in nicely on top which > detect writeback failures on remount and will shutdown fs. > Not sure why remount needs to shutdown. It needs to fail mount, but yeh, all those things should fit nicely together. Thanks, Amir.