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=-8.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 636F1C56202 for ; Wed, 21 Oct 2020 15:09:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0267D20BED for ; Wed, 21 Oct 2020 15:09:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="UfbClxFM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2443877AbgJUPJf (ORCPT ); Wed, 21 Oct 2020 11:09:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43166 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2501914AbgJUPJf (ORCPT ); Wed, 21 Oct 2020 11:09:35 -0400 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B712C0613CE; Wed, 21 Oct 2020 08:09:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:MIME-Version:Date:Message-ID:From:References:To:Subject:Sender: Reply-To:Cc:Content-ID:Content-Description; bh=JogALXxUhOTRDSLNlL38sulkhzXdXhR1YKEuIv/wTTQ=; b=UfbClxFM2J/bWwfotALuJETGVH jn8HBocgzQdLffV6pdJAjLEEVYVrCgiZp8xPR1xHVEAsmLizuXFdCJV6YENInuttJbaeaYHlk22OO UBzPF5mjIIafZPLgqPibLYQXfFmtbAltRpVavsaBA0EKU6MBZRMkgn09O7FG5flBpXeNUynkBAzl8 68XHs+y4SpbfEPAWnsBp6TfEt+s1cCo9baXPi2IMqg6ZrL9pV0XgPVeDlIY4pHLPYF5p1mAUsG7vA 1fuaJE1u7TrB8IsQbSu+Ev6Vvcyqcv9LzNj24oJqDQNrRbiMZZyv9KSBXuRQ9V5j9AXV+S0xixArw 7yW/feRw==; Received: from [2601:1c0:6280:3f0::507c] by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kVFjz-0003Y7-MR; Wed, 21 Oct 2020 15:09:27 +0000 Subject: Re: [PATCH 1/2] Block layer filter - second version To: Sergei Shtepa , axboe@kernel.dk, viro@zeniv.linux.org.uk, hch@infradead.org, darrick.wong@oracle.com, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, rjw@rjwysocki.net, len.brown@intel.com, pavel@ucw.cz, akpm@linux-foundation.org, johannes.thumshirn@wdc.com, ming.lei@redhat.com, jack@suse.cz, tj@kernel.org, gustavo@embeddedor.com, bvanassche@acm.org, osandov@fb.com, koct9i@gmail.com, damien.lemoal@wdc.com, steve@sk2.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-mm@kvack.org References: <1603271049-20681-1-git-send-email-sergei.shtepa@veeam.com> <1603271049-20681-2-git-send-email-sergei.shtepa@veeam.com> From: Randy Dunlap Message-ID: <7bd31238-0c7c-ed6f-d0b9-680fcaa54513@infradead.org> Date: Wed, 21 Oct 2020 08:09:18 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <1603271049-20681-2-git-send-email-sergei.shtepa@veeam.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 10/21/20 2:04 AM, Sergei Shtepa wrote: > diff --git a/block/Kconfig b/block/Kconfig > index bbad5e8bbffe..a308801b4376 100644 > --- a/block/Kconfig > +++ b/block/Kconfig > @@ -204,6 +204,17 @@ config BLK_INLINE_ENCRYPTION_FALLBACK > by falling back to the kernel crypto API when inline > encryption hardware is not present. > > +config BLK_FILTER > + bool "Enable support for block layer filters" > + default y Drop the default y. We don't add modules to a default build without some tough justification. > + depends on MODULES > + help > + Enabling this lets third-party kernel modules intercept lets loadable kernel modules intercept > + bio requests for any block device. This allows them to implement > + changed block tracking and snapshots without any reconfiguration of > + the existing setup. For example, this option allows snapshotting of > + a block device without adding it to LVM. -- ~Randy