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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 90E19C433EF for ; Fri, 10 Sep 2021 06:45:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75D4D611B0 for ; Fri, 10 Sep 2021 06:45:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231255AbhIJGqT (ORCPT ); Fri, 10 Sep 2021 02:46:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:34178 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231223AbhIJGqT (ORCPT ); Fri, 10 Sep 2021 02:46:19 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 71E3E6109F; Fri, 10 Sep 2021 06:45:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1631256308; bh=zs4kHzRc2dEOg/Ypc3inBLRklRqv/MDp+aMdgAMUJvo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=arZpI6Vbkd1Q4i3uXv3VOMwXkAB9fZUzJYRhC8canCV48cmeaid4vVaHL6S35gBYk 1r2JfmDm9NFy+1X6JVvhICj3bQFHl/EVf52LImze8YXwP8PGLdAUmQV84ndyDMvxTv NXCgtswiAFDW6aYrzFAElN/he9LdzZHmHPxjjlG0= Date: Fri, 10 Sep 2021 08:45:06 +0200 From: Greg KH To: Ian Pilcher Cc: axboe@kernel.dk, pavel@ucw.cz, linux-leds@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, kabel@kernel.org Subject: Re: [PATCH v2 06/15] leds: trigger: blkdev: Add function to get gendisk by name Message-ID: References: <20210909222513.2184795-1-arequipeno@gmail.com> <20210909222513.2184795-7-arequipeno@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210909222513.2184795-7-arequipeno@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Sep 09, 2021 at 05:25:04PM -0500, Ian Pilcher wrote: > Add ledtrig_blkdev_get_disk() to find block device by name and increment > its reference count. (Caller must call put_disk().) Must be built-in to > access block_class and disk_type symbols. > > Signed-off-by: Ian Pilcher > --- > drivers/leds/trigger/ledtrig-blkdev-core.c | 20 ++++++++++++++++++++ > drivers/leds/trigger/ledtrig-blkdev.h | 3 +++ > 2 files changed, 23 insertions(+) > > diff --git a/drivers/leds/trigger/ledtrig-blkdev-core.c b/drivers/leds/trigger/ledtrig-blkdev-core.c > index d7b02e760b06..5fd741aa14a6 100644 > --- a/drivers/leds/trigger/ledtrig-blkdev-core.c > +++ b/drivers/leds/trigger/ledtrig-blkdev-core.c > @@ -33,3 +33,23 @@ void ledtrig_blkdev_disk_cleanup(struct gendisk *const gd) > > mutex_unlock(&ledtrig_blkdev_mutex); > } > + > +/* class_find_device() callback. Must be built-in to access disk_type. */ > +static int blkdev_match_name(struct device *const dev, const void *const name) > +{ > + return dev->type == &disk_type > + && sysfs_streq(dev_to_disk(dev)->disk_name, name); > +} > + > +/* Must be built-in to access block_class */ > +struct gendisk *ledtrig_blkdev_get_disk(const char *const name) > +{ > + struct device *dev; > + > + dev = class_find_device(&block_class, NULL, name, blkdev_match_name); > + if (dev == NULL) > + return NULL; You now have bumped the reference count on this structure. Where do you decrement it when you are finished with it? thanks, greg k-h