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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 613BDC00140 for ; Wed, 24 Aug 2022 19:00:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239547AbiHXTAw (ORCPT ); Wed, 24 Aug 2022 15:00:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239633AbiHXTAu (ORCPT ); Wed, 24 Aug 2022 15:00:50 -0400 Received: from mail-oa1-x33.google.com (mail-oa1-x33.google.com [IPv6:2001:4860:4864:20::33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F05CBB851 for ; Wed, 24 Aug 2022 12:00:48 -0700 (PDT) Received: by mail-oa1-x33.google.com with SMTP id 586e51a60fabf-11ba6e79dd1so21988305fac.12 for ; Wed, 24 Aug 2022 12:00:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc; bh=fjATRPE4m83dckDCIc8OGRxnjlPksG8X6iPw0ydnz/g=; b=OFes1KyQ5IWJewh4On/mqFjyS9IYL+/2BQOpEhwzvRnMN1Woi/vf7JbPVhedRpkDz/ Pd9lADPzWrkaoZ97kmoV/6PBvTMYPj4AtHqs5JOqP8lAndXh3ix/TRey9LEF4kBMCm2l AwCK9jVi768DMiNjjAKSE6J42WwU7XrMMDA4EZIkBKRU6IFigu9GjTmvAfklDhlPhE6I sqG3/Fr+LxnD2LPNw1rjdwMvamUHZUBfveQE5c3rHfOfhi/9a72uxDNeQrXkXg73Ax6E DZEXMhbWwTG0aTc9Z68ED5IHupAu8p1+n4FjQW7mgU9rX2WoKTMJBU0ncP+FEV9dEI2Q x4Cw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=fjATRPE4m83dckDCIc8OGRxnjlPksG8X6iPw0ydnz/g=; b=SC42RA9d8lcDi1sOXL7/q+VBSqjh1lHyzg60PBBPEB57CTiu27m2kslZZu2Ef78WC9 SqYgTsKp0DiuQQPT0TTXy00zIjUa/HuTpP2/o3qjtBv5QuEo/sVRStDDOkc7QWZctufU af1aPAVE7Ul1exwxtgQj0BteN/YozwNi7LbkVygXVtpeH17mVWbv/tGrxnpPOEGqKDy7 O8jf0wIQ1TiyldQHG7K4h3dFbMJc/t7xfNwfV/XyI+4QVCEWvzAO6KiC9a6gt/ufHORG suc6EhdXz/Ii8hZ+4NWylEXf47JN2+r3E3qGru2BFgwVt1np7N7vJTLH0Nx9eVZXDSR1 3ZIg== X-Gm-Message-State: ACgBeo0KVSV6z3zJ97aEgSSc4W10RL+KoSgru6JSo6q9dGdhjGwM/mP3 Qjc0IFdPvame+v4RpkOyypcfJmA9et+sL3DcvowbjK4kQmY= X-Google-Smtp-Source: AA6agR6dmJt4QfNyqc4L39igPlAU/Rlixc4K3tcFcuxJaomjMcNtUbkT4h0KsNvE6tscC81KAVnKQweaCifHwnFUH7U= X-Received: by 2002:a05:6870:310:b0:f1:f473:a53f with SMTP id m16-20020a056870031000b000f1f473a53fmr4489944oaf.34.1661367648134; Wed, 24 Aug 2022 12:00:48 -0700 (PDT) MIME-Version: 1.0 References: <20200728234513.1956039-1-ytht.net@gmail.com> In-Reply-To: From: lepton Date: Wed, 24 Aug 2022 12:00:37 -0700 Message-ID: Subject: Re: [PATCH] fuse: Add filesystem attribute in sysfs control dir. To: Miklos Szeredi Cc: linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, Aug 22, 2022 at 6:37 AM Miklos Szeredi wrote: > > On Wed, 29 Jul 2020 at 01:45, Lepton Wu wrote: > > > > With this, user space can have more control to just abort some kind of > > fuse connections. Currently, in Android, it will write to abort file > > to abort all fuse connections while in some cases, we'd like to keep > > some fuse connections. This can help that. > > You can grep the same info from /proc/self/mountinfo. Why does that not work? Hi Miklos, thanks for this hint. That will work. But the code in user space will be more complicated and not straightforward. For now, I can see 2 issues with mountinfo: 1. one connection could have multiple entries under /proc/self/mountinfo if there are bind mounts, user space code needs to handle that. 2. /proc/self/mountinfo is limited by namespace, so in theory, some connection under /sys/fs/fuse/connections could be missed in it. While this isn't an issue for the current android code, maybe it could get broken in the future. Overall, I am feeling my kernel patch is a straightforward and simple solution and it's just one more attribute under /sys/fs/fuse/connections, may I know if there are any downsides to doing this? Thanks! > > Thanks, > Miklos