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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 864B7C433F5 for ; Mon, 27 Aug 2018 10:34:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37C60208B8 for ; Mon, 27 Aug 2018 10:34:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 37C60208B8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726953AbeH0OUM (ORCPT ); Mon, 27 Aug 2018 10:20:12 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:49904 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726785AbeH0OUM (ORCPT ); Mon, 27 Aug 2018 10:20:12 -0400 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w7RAXiBl122881 for ; Mon, 27 Aug 2018 06:34:06 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2m4e3dkje4-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 27 Aug 2018 06:34:06 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 27 Aug 2018 11:33:57 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w7RAXu0636176074 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 27 Aug 2018 10:33:56 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3ACF74C040; Mon, 27 Aug 2018 13:33:56 +0100 (BST) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9BFB34C046; Mon, 27 Aug 2018 13:33:54 +0100 (BST) Received: from rapoport-lnx (unknown [9.148.8.97]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Mon, 27 Aug 2018 13:33:54 +0100 (BST) Date: Mon, 27 Aug 2018 13:33:53 +0300 From: Mike Rapoport To: Bartosz Golaszewski Cc: Michael Turquette , Stephen Boyd , Greg Kroah-Hartman , "Rafael J . Wysocki" , Arend van Spriel , Ulf Hansson , Bjorn Helgaas , Vivek Gautam , Robin Murphy , Joe Perches , Heikki Krogerus , Andrew Morton , Michal Hocko , Al Viro , Jonathan Corbet , Roman Gushchin , Huang Ying , Kees Cook , Bjorn Andersson , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/2] devres: provide devm_kstrdup_const() References: <20180827082101.5036-1-brgl@bgdev.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180827082101.5036-1-brgl@bgdev.pl> User-Agent: Mutt/1.5.24 (2015-08-30) X-TM-AS-GCONF: 00 x-cbid: 18082710-0012-0000-0000-0000029F418C X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18082710-0013-0000-0000-000020D3442E Message-Id: <20180827103353.GB13848@rapoport-lnx> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-08-27_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1808270115 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 27, 2018 at 10:21:00AM +0200, Bartosz Golaszewski wrote: > Provide a resource managed version of kstrdup_const(). This variant > internally calls devm_kstrdup() on pointers that are outside of > .rodata section. Also provide a corresponding version of devm_kfree(). > > Signed-off-by: Bartosz Golaszewski > --- > include/linux/device.h | 2 ++ > mm/util.c | 35 +++++++++++++++++++++++++++++++++++ > 2 files changed, 37 insertions(+) > > diff --git a/include/linux/device.h b/include/linux/device.h > index 8f882549edee..f8f5982d26b2 100644 > --- a/include/linux/device.h > +++ b/include/linux/device.h > @@ -693,7 +693,9 @@ static inline void *devm_kcalloc(struct device *dev, > return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO); > } > extern void devm_kfree(struct device *dev, void *p); > +extern void devm_kfree_const(struct device *dev, void *p); > extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc; > +extern char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp); > extern void *devm_kmemdup(struct device *dev, const void *src, size_t len, > gfp_t gfp); > > diff --git a/mm/util.c b/mm/util.c > index d2890a407332..6d1f41b5775e 100644 > --- a/mm/util.c > +++ b/mm/util.c > @@ -39,6 +39,20 @@ void kfree_const(const void *x) > } > EXPORT_SYMBOL(kfree_const); > > +/** > + * devm_kfree_const - Resource managed conditional kfree > + * @dev: device this memory belongs to > + * @p: memory to free > + * > + * Function calls devm_kfree only if @p is not in .rodata section. > + */ > +void devm_kfree_const(struct device *dev, void *p) > +{ > + if (!is_kernel_rodata((unsigned long)p)) > + devm_kfree(dev, p); > +} > +EXPORT_SYMBOL(devm_kfree_const); > + > /** > * kstrdup - allocate space for and copy an existing string > * @s: the string to duplicate > @@ -78,6 +92,27 @@ const char *kstrdup_const(const char *s, gfp_t gfp) > } > EXPORT_SYMBOL(kstrdup_const); > > +/** > + * devm_kstrdup_const - resource managed conditional string duplication > + * @dev: device for which to duplicate the string > + * @s: the string to duplicate > + * @gfp: the GFP mask used in the kmalloc() call when allocating memory > + * > + * Function returns source string if it is in .rodata section otherwise it > + * fallbacks to devm_kstrdup. Please make it proper "Returns:" description and move to the end of the comment. See Documentation/doc-guide/kernel-doc.rst. > + * Strings allocated by devm_kstrdup_const will be automatically freed when > + * the associated device is detached. > + */ > +char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp) > +{ > + if (is_kernel_rodata((unsigned long)s)) > + return s; > + > + return devm_kstrdup(dev, s, gfp); > +} > +EXPORT_SYMBOL(devm_kstrdup_const); > + The devm_ variants seem to belong to drivers/base/devres.c rather than mm/util.c > /** > * kstrndup - allocate space for and copy an existing string > * @s: the string to duplicate > -- > 2.18.0 > -- Sincerely yours, Mike.