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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 4FA2EC10F13 for ; Tue, 16 Apr 2019 14:19:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 194BF223FD for ; Tue, 16 Apr 2019 14:19:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555424399; bh=tj2oqLYULvvLSyNlQMoQuuGucML1O57tO2NXSD6MMnM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=PjKBGiEo4zVIwQQHnVGrJOsH7AM26V5Wz4ky0Pb0mopOhehebrWWEA89uCvPh2Na8 5armC/BL59DokMLKq97BOp1I60GBtINNlucGml9ZOJ5NDuUUWxUsifMg6QLDn7g4dT +TeXiP3LBArKNSSgEySG9s0L41EBJJPtlT027fBw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729057AbfDPOT6 (ORCPT ); Tue, 16 Apr 2019 10:19:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:58736 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725796AbfDPOT5 (ORCPT ); Tue, 16 Apr 2019 10:19:57 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 57B4F223F9; Tue, 16 Apr 2019 14:19:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555424396; bh=tj2oqLYULvvLSyNlQMoQuuGucML1O57tO2NXSD6MMnM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IJ9Ugu4BLptS71Y5CUndU9to8xBxIx9YUjFVS3nLcFphIdrBMZDUJxUnCVUWEw9a2 vSEW5cqc+unS5wiqaxbjraJGKfzZR0TulGBDx32W9eUcJOkZTCAsDIFg0ousLmk1v0 AnH29CN1Hp3SLE5HZvFPL/vwhq4TRu69aFODtQK4= Date: Tue, 16 Apr 2019 15:29:25 +0200 From: Greg Kroah-Hartman To: "Life is hard, and then you die" Cc: Jonathan Corbet , "Rafael J. Wysocki" , Andy Shevchenko , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] debugfs: make return value of all debugfs helpers consistent Message-ID: <20190416132925.GA17483@kroah.com> References: <20190415082506.25610-1-ronald@innovation.ch> <20190415082506.25610-3-ronald@innovation.ch> <20190415084844.GA26101@kroah.com> <20190415232959.GC13033@innovation.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190415232959.GC13033@innovation.ch> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 15, 2019 at 04:29:59PM -0700, Life is hard, and then you die wrote: > > Hi Greg, > > On Mon, Apr 15, 2019 at 10:48:44AM +0200, Greg Kroah-Hartman wrote: > > On Mon, Apr 15, 2019 at 01:25:06AM -0700, Ronald Tschalär wrote: > > > Since commit ff9fb72bc077 ("debugfs: return error values, not NULL") > > > almost all the debugfs helpers have stopped returning NULL. The lone > > > holdeout was debugfs_create_u32_array(). So fix that. > > > > > > Signed-off-by: Ronald Tschalär > > > --- > > > fs/debugfs/file.c | 6 +++--- > > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > > > diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c > > > index ddd708b09fa1..bb706d073782 100644 > > > --- a/fs/debugfs/file.c > > > +++ b/fs/debugfs/file.c > > > @@ -999,8 +999,8 @@ static const struct file_operations u32_array_fops = { > > > * Once array is created its size can not be changed. > > > * > > > * The function returns a pointer to dentry on success. If an error occurs, > > > - * %ERR_PTR(-ERROR) or NULL will be returned. If debugfs is not enabled in > > > - * the kernel, the value %ERR_PTR(-ENODEV) will be returned. > > > + * %ERR_PTR(-ERROR) will be returned. If debugfs is not enabled in the kernel, > > > + * the value %ERR_PTR(-ENODEV) will be returned. > > > */ > > > struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, > > > struct dentry *parent, > > > @@ -1009,7 +1009,7 @@ struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, > > > struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL); > > > > > > if (data == NULL) > > > - return NULL; > > > + return ERR_PTR(-ENOMEM); > > > > > > data->array = array; > > > data->elements = elements; > > > > There is only one caller of this function in the kernel now, and it does > > not even care about the return value at all, so we should just remove > > the return value entirely as that's the easiest and best thing to do > > here. > > Interesting argument: since this is a helper/library function, and > therefore potentially used in the future by others, it seems to me > that consistency with the other functions and providing error feedback > would be important. Not if you never actually use the return value for anything :) > > I was going to start doing this slowly over time, but as you are > > touching the function now, might as well do it here :) > > Are you saying the plan is to make all these helpers return void? Yes, no caller should do anything "different" based on a return value of a debugfs call. Note, sometimes you do want to save off dentries for some files that you later remove, but that's it. thanks, greg k-h