From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp0 ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms11 with LMTPS id mBaxIikabl+3EgAA0tVLHw (envelope-from ) for ; Fri, 25 Sep 2020 16:26:17 +0000 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp0 with LMTPS id iDioHikabl+/NwAA1q6Kng (envelope-from ) for ; Fri, 25 Sep 2020 16:26:17 +0000 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id A912F940663 for ; Fri, 25 Sep 2020 16:26:16 +0000 (UTC) Received: from localhost ([::1]:44516 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLqY2-00019o-2n for larch@yhetil.org; Fri, 25 Sep 2020 12:26:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47120) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kLqT0-0002x2-PP for guix-patches@gnu.org; Fri, 25 Sep 2020 12:21:02 -0400 Received: from debbugs.gnu.org ([209.51.188.43]:33619) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kLqT0-0006Wz-F5 for guix-patches@gnu.org; Fri, 25 Sep 2020 12:21:02 -0400 Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1kLqT0-00037N-AZ for guix-patches@gnu.org; Fri, 25 Sep 2020 12:21:02 -0400 X-Loop: help-debbugs@gnu.org Subject: [bug#41143] [PATCH 1/2] mapped-devices: Allow target to be list of strings Resent-From: Ludovic =?UTF-8?Q?Court=C3=A8s?= Original-Sender: "Debbugs-submit" Resent-CC: guix-patches@gnu.org Resent-Date: Fri, 25 Sep 2020 16:21:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 41143 X-GNU-PR-Package: guix-patches X-GNU-PR-Keywords: patch To: Mikhail Tsykalov Cc: 41143@debbugs.gnu.org Received: via spool by 41143-submit@debbugs.gnu.org id=B41143.160105086111959 (code B ref 41143); Fri, 25 Sep 2020 16:21:02 +0000 Received: (at 41143) by debbugs.gnu.org; 25 Sep 2020 16:21:01 +0000 Received: from localhost ([127.0.0.1]:45165 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kLqSy-00036p-SJ for submit@debbugs.gnu.org; Fri, 25 Sep 2020 12:21:01 -0400 Received: from eggs.gnu.org ([209.51.188.92]:40264) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kLqSx-00036d-FM for 41143@debbugs.gnu.org; Fri, 25 Sep 2020 12:21:00 -0400 Received: from fencepost.gnu.org ([2001:470:142:3::e]:39854) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLqSs-0006WC-5j; Fri, 25 Sep 2020 12:20:54 -0400 Received: from [2a01:e0a:1d:7270:af76:b9b:ca24:c465] (port=33164 helo=ribbon) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1kLqSr-0005tR-G0; Fri, 25 Sep 2020 12:20:53 -0400 From: Ludovic =?UTF-8?Q?Court=C3=A8s?= References: <874ko6n0s5.fsf@gnu.org> <9ac560cc-8660-f034-c0d8-536b68d20f68@gmail.com> <87r1qq2o92.fsf@gnu.org> X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 4 =?UTF-8?Q?Vend=C3=A9miaire?= an 229 de la =?UTF-8?Q?R=C3=A9volution?= X-PGP-Key-ID: 0x090B11993D9AEBB5 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 3CE4 6455 8A84 FDC6 9DB4 0CFB 090B 1199 3D9A EBB5 X-OS: x86_64-pc-linux-gnu Date: Fri, 25 Sep 2020 18:20:51 +0200 In-Reply-To: (Mikhail Tsykalov's message of "Fri, 25 Sep 2020 16:36:11 +0300") Message-ID: <87pn69j09o.fsf@gnu.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Score: -2.3 (--) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-Spam-Score: -3.3 (---) X-BeenThere: guix-patches@gnu.org List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-patches-bounces+larch=yhetil.org@gnu.org Sender: "Guix-patches" X-Scanner: scn0 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=pass (policy=none) header.from=gnu.org; spf=pass (aspmx1.migadu.com: domain of guix-patches-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=guix-patches-bounces@gnu.org X-Spam-Score: -1.51 X-TUID: H2DVWdBJLNXw Hi, Mikhail Tsykalov skribis: [...] >>> While this looks like a good idea, doesn't this break code that >>> implements mapped-device and assumes that target is a string. Suddenly >>> passing a string to a mapped-device constructor results in a list >>> passed to open/close. Also, what functions should do if they expect a >>> string but get a list of them? Ignore everything but the first item? >>> Implement mandatory check function? Doesn't this change push >>> complexity out of mapped-device to implementations of it. >> The intent of what I propose above is (1) to not break existing code, >> and (2) to avoid duplicating checks and conversions at every call site. >> >> #1 is achieved by providing a deprecated =E2=80=98mapped-device-target= =E2=80=99 >> (singular) procedure, for example. >> >> Does that make sense? > > I'm sorry if I didn't make myself clear, but it doesn't seem like > open/close functions even use any mapped-device-* procedures, they > just get passed source and target field directly. What I meant was > this change will require changes to luks-device-mapping, > raid-device-mapping and all other device mappings that users may have > implemented in their local trees/config. Ah yes, got it. I tend to think it=E2=80=99s OK though, if we assume all the implementation= s are in-tree, which would be consistent with the fact that the internals (how to implement a mapped device type) are undocumented. WDYT? IOW, I think we must provide compatibility for users (people writing their OS config, including perhaps service definitions) while leaving us the ability to change internal interfaces. Thanks, Ludo=E2=80=99.