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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 455D8C5DF62 for ; Wed, 6 Nov 2019 03:26:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DDE3205C9 for ; Wed, 6 Nov 2019 03:26:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731051AbfKFD0l (ORCPT ); Tue, 5 Nov 2019 22:26:41 -0500 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:57284 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730655AbfKFD0l (ORCPT ); Tue, 5 Nov 2019 22:26:41 -0500 Received: from callcc.thunk.org (ip-12-2-52-196.nyc.us.northamericancoax.com [196.52.2.12]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id xA63QMGp027897 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 5 Nov 2019 22:26:23 -0500 Received: by callcc.thunk.org (Postfix, from userid 15806) id 4AC21420311; Tue, 5 Nov 2019 22:26:20 -0500 (EST) Date: Tue, 5 Nov 2019 22:26:20 -0500 From: "Theodore Y. Ts'o" To: Eric Biggers Cc: linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, Satya Tangirala , Paul Crowley , Paul Lawrence , Jaegeuk Kim Subject: Re: [PATCH v2 2/3] ext4: add support for IV_INO_LBLK_64 encryption policies Message-ID: <20191106032620.GF26959@mit.edu> References: <20191024215438.138489-1-ebiggers@kernel.org> <20191024215438.138489-3-ebiggers@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191024215438.138489-3-ebiggers@kernel.org> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Thu, Oct 24, 2019 at 02:54:37PM -0700, Eric Biggers wrote: > From: Eric Biggers > > IV_INO_LBLK_64 encryption policies have special requirements from the > filesystem beyond those of the existing encryption policies: > > - Inode numbers must never change, even if the filesystem is resized. > - Inode numbers must be <= 32 bits. > - File logical block numbers must be <= 32 bits. > > ext4 has 32-bit inode and file logical block numbers. However, > resize2fs can re-number inodes when shrinking an ext4 filesystem. > > However, typically the people who would want to use this format don't > care about filesystem shrinking. They'd be fine with a solution that > just prevents the filesystem from being shrunk. > > Therefore, add a new feature flag EXT4_FEATURE_COMPAT_STABLE_INODES that > will do exactly that. Then wire up the fscrypt_operations to expose > this flag to fs/crypto/, so that it allows IV_INO_LBLK_64 policies when > this flag is set. > > Signed-off-by: Eric Biggers LGTM Acked-by: Theodore Ts'o - Ted