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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 21074C43603 for ; Tue, 17 Dec 2019 16:34:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E7E8A21582 for ; Tue, 17 Dec 2019 16:34:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Ww+Gn2Ab" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728057AbfLQQen (ORCPT ); Tue, 17 Dec 2019 11:34:43 -0500 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:34975 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727802AbfLQQen (ORCPT ); Tue, 17 Dec 2019 11:34:43 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576600482; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JRhNoK6ecjIEWZT9z2fmsJ4MliKY9CsSRK7g7FgLN48=; b=Ww+Gn2AbkUNG/CNkFhUnw2sRPVt6ku+6qz7WvfrDualtFbRSRjbUWWcMkHNST9vwKyySLW s1xBmsQ3fpOnBWOYCXauliZz8ZGosCtKUHVW+RnRjpK3F06ZX/X3IpeQ19u4fUP3KgUk2L H9VXhbGV9wClhML0Mfd1CIjaImkpHOI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-130-Jlr96TkuPL-rvRrrR78slg-1; Tue, 17 Dec 2019 11:34:38 -0500 X-MC-Unique: Jlr96TkuPL-rvRrrR78slg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C6748DBA7; Tue, 17 Dec 2019 16:34:37 +0000 (UTC) Received: from work (ovpn-205-130.brq.redhat.com [10.40.205.130]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B232E100164D; Tue, 17 Dec 2019 16:34:36 +0000 (UTC) Date: Tue, 17 Dec 2019 17:34:32 +0100 From: Lukas Czerner To: Al Viro Cc: linux-ext4@vger.kernel.org, Theodore Ts'o , David Howells Subject: Re: [PATCH 02/17] ext4: Add fs parameter description Message-ID: <20191217163432.diborehdrfkmfqxp@work> References: <20191106101457.11237-1-lczerner@redhat.com> <20191106101457.11237-3-lczerner@redhat.com> <20191217004419.GA6833@ZenIV.linux.org.uk> <20191217121956.amsymslmuoy6kzu4@work> <20191217152012.GY4203@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191217152012.GY4203@ZenIV.linux.org.uk> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Tue, Dec 17, 2019 at 03:20:12PM +0000, Al Viro wrote: > On Tue, Dec 17, 2019 at 01:19:56PM +0100, Lukas Czerner wrote: > > On Tue, Dec 17, 2019 at 12:44:19AM +0000, Al Viro wrote: > > > On Wed, Nov 06, 2019 at 11:14:42AM +0100, Lukas Czerner wrote: > > > > + fsparam_string_empty > > > > + ("usrjquota", Opt_usrjquota), > > > > + fsparam_string_empty > > > > + ("grpjquota", Opt_grpjquota), > > > > > > Umm... That makes ...,usrjquota,... equivalent to ...,usrjquota=,... > > > unless I'm misreading the series. Different from mainline, right? > > > > Unfortunatelly yes, I do not think this is a problem, but if you have a > > solution within the new mount api framework I am happy to use it. > > Er... Dump the fsparam_string_empty() use and instead of your > + if (token == Opt_usrjquota) { > + if (result.negated) > + return clear_qf_name(sb, USRQUOTA); > + else > + return set_qf_name(sb, USRQUOTA, param); > do > + if (token == Opt_usrjquota) { > + if (!param->string[0]) > + return clear_qf_name(sb, USRQUOTA); > + else > + return set_qf_name(sb, USRQUOTA, param); > with the same for grpjquota? Ah right, it's been a while I guess I didn't realize that it will accept usrjquota as well as usrjquota= It makes sense to check the string directly, thanks. > > > > > + fsparam_bool ("barrier", Opt_barrier), > > > > + fsparam_flag ("nobarrier", Opt_nobarrier), > > > > > > That's even more interesting. Current mainline: > > > barrier OK, sets EXT4_MOUNT_BARRIER > > > barrier=0 OK, sets EXT4_MOUNT_BARRIER > > > barrier=42 OK, sets EXT4_MOUNT_BARRIER > > > barrier=yes error > > > barrier=no error > > > nobarrier OK, clears EXT4_MOUNT_BARRIER > > > Unless I'm misreading your series, you get > > > barrier error > > > > Not really, this seems to be working as expected. Assuming that this > > didn't change since 5.4.0-rc6. I does make sense to me that specifying > > bool type parameter without any options would express "true". > > > > > > > barrier=0 OK, sets EXT4_MOUNT_BARRIER > > > > > > > barrier=42 error > > > barrier=yes OK, sets EXT4_MOUNT_BARRIER > > > barrier=no OK, sets EXT4_MOUNT_BARRIER > > > > Those three are different, just because of how param_book() work. I do > > not really see a problem with it, but if we want to keep it exactly the > > same as current mainline it would be difficult with how the current api > > works. Any suggestions ? > > If fsparam_bool() doesn't do the right thing, perhaps it shouldn't be > used in the first place? Or changed, for that matter - it's not as if > we had many users of that thing and the only in-tree one is definitely > breaking userland ABI. > > In case of ext4, after rereading that code (and getting some sleep) the > current behaviour is, AFAICS to accept barrier | nobarrier | barrier= > with the last case being equialent to nobarrier when number is 0 and barrier > in all other cases. Is that an accurate description? Yeah, the documentation says barrier=0 / barrier=1 / barrier / nobarrier but we do accept any number from 0 to 2147483647 > > If so, I would prefer > fsparam_flag_no("barrier", Opt_barrier), // barrier | nobarrier > fsparam_u32("barrier", Opt_barrier), // barrier= > as the solution, with fs_parse() having been taught to allow argument-bearing > and argument-less options with the same name, picking the right one. That > way Opt_nobarrier gets removed as well... > > I'll push a branch with that stuff later today; will post when it's out... That would be great, thanks. -Lukas