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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9C07DC47247 for ; Tue, 5 May 2020 17:31:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7CCAD20752 for ; Tue, 5 May 2020 17:31:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588699870; bh=RzTvVkH2WVsAJ6Ltt5T27ZrW2749b4NieHGvxtLnG9U=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=fs+/ihqEGpPSE47Lof3hDp8v9leRrRsdHCORmnuI+wZ8bPaBg0IpXYeGj07UdJgeD fpixkTy6ORZRD5kxa0tMq3EgaEOe93NCJhmectCEAGTgq/0zzNooARWhf3ojH7h4YJ IKvxvF6ynl4aic+rEngEInmf8K9XwMtraSVOSHAM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730615AbgEERbK (ORCPT ); Tue, 5 May 2020 13:31:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:35802 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729885AbgEERbJ (ORCPT ); Tue, 5 May 2020 13:31:09 -0400 Received: from kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com (unknown [163.114.132.1]) (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 B9FE720721; Tue, 5 May 2020 17:31:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588699868; bh=RzTvVkH2WVsAJ6Ltt5T27ZrW2749b4NieHGvxtLnG9U=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=tS/u1wcR0Q37TVJw/uE8YgnBhtgDScfuck9IX7Q0iLQGTfwFyd8odJaD2kcrM82p6 HjikTR5ZOMjXfxiIlj5H/zEWp1Gzef+QoT68Q1tJlotQrUUW0jX83S4VT/HyNN8eNj i+2HZEa5Zj1G4Fze1Kx4NNapdEWOsffuC7brNBus= Date: Tue, 5 May 2020 10:31:05 -0700 From: Jakub Kicinski To: Bartosz Golaszewski Cc: Rob Herring , "David S . Miller" , Matthias Brugger , Felix Fietkau , John Crispin , Sean Wang , Mark Lee , Arnd Bergmann , Fabien Parent , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Bartosz Golaszewski Subject: Re: [PATCH 05/11] net: core: provide devm_register_netdev() Message-ID: <20200505103105.1c8b0ce3@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20200505140231.16600-6-brgl@bgdev.pl> References: <20200505140231.16600-1-brgl@bgdev.pl> <20200505140231.16600-6-brgl@bgdev.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 5 May 2020 16:02:25 +0200 Bartosz Golaszewski wrote: > From: Bartosz Golaszewski > > Provide devm_register_netdev() - a device resource managed variant > of register_netdev(). This new helper will only work for net_device > structs that have a parent device assigned and are devres managed too. > > Signed-off-by: Bartosz Golaszewski > diff --git a/net/core/dev.c b/net/core/dev.c > index 522288177bbd..99db537c9468 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -9519,6 +9519,54 @@ int register_netdev(struct net_device *dev) > } > EXPORT_SYMBOL(register_netdev); > > +struct netdevice_devres { > + struct net_device *ndev; > +}; Is there really a need to define a structure if we only need a pointer? > +static void devm_netdev_release(struct device *dev, void *this) > +{ > + struct netdevice_devres *res = this; > + > + unregister_netdev(res->ndev); > +} > + > +/** > + * devm_register_netdev - resource managed variant of register_netdev() > + * @ndev: device to register > + * > + * This is a devres variant of register_netdev() for which the unregister > + * function will be call automatically when the parent device of ndev > + * is detached. > + */ > +int devm_register_netdev(struct net_device *ndev) > +{ > + struct netdevice_devres *dr; > + int ret; > + > + /* struct net_device itself must be devres managed. */ > + BUG_ON(!(ndev->priv_flags & IFF_IS_DEVRES)); > + /* struct net_device must have a parent device - it will be the device > + * managing this resource. > + */ > + BUG_ON(!ndev->dev.parent); Please convert those to WARN_ON, and return an error. No need to crash the kernel. > + dr = devres_alloc(devm_netdev_release, sizeof(*dr), GFP_KERNEL); > + if (!dr) > + return -ENOMEM; > + > + ret = register_netdev(ndev); > + if (ret) { > + devres_free(dr); > + return ret; > + } > + > + dr->ndev = ndev; > + devres_add(ndev->dev.parent, dr); > + > + return 0; > +} > +EXPORT_SYMBOL(devm_register_netdev);