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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 2E0F8C433DF for ; Thu, 20 Aug 2020 10:49:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 06EEA2075E for ; Thu, 20 Aug 2020 10:49:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=paragon-software.com header.i=@paragon-software.com header.b="aVOB/NFo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731621AbgHTKs6 (ORCPT ); Thu, 20 Aug 2020 06:48:58 -0400 Received: from relayfre-01.paragon-software.com ([176.12.100.13]:33814 "EHLO relayfre-01.paragon-software.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731233AbgHTKsx (ORCPT ); Thu, 20 Aug 2020 06:48:53 -0400 Received: from dlg2.mail.paragon-software.com (vdlg-exch-02.paragon-software.com [172.30.1.105]) by relayfre-01.paragon-software.com (Postfix) with ESMTPS id 3A701223; Thu, 20 Aug 2020 13:48:50 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=paragon-software.com; s=mail; t=1597920530; bh=9cTYIIJs4bB6m90q1Q33yf9+CsB+AZVqOTe8LJv4/ww=; h=From:To:CC:Subject:Date:References:In-Reply-To; b=aVOB/NFoG4pG0LP5c29U+0JbKiEmNLTgguYMcNnw8D/mSNHFjhy86Frui5j9mCU4B x0jgGpZW/4eUidx3C0zPQbegivfE93OMslZzvamvQtg0qT5BjfxFpV0wRB14lCxG5n aWSXN7XhoMwCZUDeNtxZRyvL02/gtiAqN4dgIF4g= Received: from vdlg-exch-02.paragon-software.com (172.30.1.105) by vdlg-exch-02.paragon-software.com (172.30.1.105) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1847.3; Thu, 20 Aug 2020 13:48:49 +0300 Received: from vdlg-exch-02.paragon-software.com ([fe80::586:6d72:3fe5:bd9b]) by vdlg-exch-02.paragon-software.com ([fe80::586:6d72:3fe5:bd9b%6]) with mapi id 15.01.1847.003; Thu, 20 Aug 2020 13:48:49 +0300 From: Konstantin Komarov To: "dsterba@suse.cz" CC: "viro@zeniv.linux.org.uk" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" Subject: RE: [PATCH] fs: NTFS read-write driver GPL implementation by Paragon Software. Thread-Topic: [PATCH] fs: NTFS read-write driver GPL implementation by Paragon Software. Thread-Index: AdZyNcmjSkpkGje7R9K6YobJrVDyZwA6EcIAAPAHtmA= Date: Thu, 20 Aug 2020 10:48:49 +0000 Message-ID: References: <2911ac5cd20b46e397be506268718d74@paragon-software.com> <20200815190642.GZ2026@twin.jikos.cz> In-Reply-To: <20200815190642.GZ2026@twin.jikos.cz> Accept-Language: ru-RU, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [172.30.8.36] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: David Sterba Sent: Saturday, August 15, 2020 10:07 PM >=20 > 1. check existing support in kernel >=20 > There is fs/ntfs with read-only support from Tuxera, last change in the > git tree is 3 years ago. The driver lacks read-write support so there's > not 100% functionality duplication but there's still driver for the same > filesystem. >=20 > I don't know what's the feature parity, how much the in-kernel driver is > used (or what are business relations of Tuxera and Paragon), compared to > the FUSE-based driver, but ideally there's just one NTFS driver in linux > kernel. >=20 > The question I'd ask: >=20 > - what are users of current fs/ntfs driver going to lose, if the driver > is going to be completely replaced by your driver >=20 > If the answer is 'nothing' then, the straightfowrad plan is to just > replace it. Otherwise, we'll have to figure that out. Hi! Regarding the comparison with fs/ntfs driver - we of course did the ana= lysis. There are two main points which make the difference: full read-write= support (including compressed/sparse files) and journal replaying. The one= thing which is missing in fs/ntfs3 in the inital patch is the appropriate = processing of hybernated volumes (mounting them read-only to avoid corrupti= ons). This, however, is considered as trivial change and will be added eith= er in v2, or in v3. In general, we want to have the community's feedback on= the topic, and if it's more suitable for the Linux Kernel not to have two = implementations in Kernel, then the 'fs/ntfs' may be replaced. =20 >=20 > 2. split the patch >=20 > One patch of 27k lines of code is way too much to anybody to look at. The patch will be splitted in v2 file-wise. Wasn't clear initially which wa= y will be more convenient to review. > 3. determine support status >=20 > You state intentions to work on the driver and there's a new entry in > MAINTAINERS file with 'Supported', so that's a good sign that it's not > just one-time dump of code. Fixing bugs or adding functionality is > expected. >=20 > 4. development git tree >=20 > Once the filesystem is merged, you'd be getting mails from people > running eg. static checkers, build tests, sending cleanups or other > tree-wide changes. The entry in MAINTAINER file does not point to any > git tree, so that's not clear to me what's the expected way to get the > fixes to Linus' tree or where are people supposed to look for 'is this > fixed already'. The external git repo for the code is currently being prepared, so it's the= matter of time to have it. Will add the appropriate links to the MAINTERS = once done.