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=-8.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 1DC05C432BE for ; Tue, 10 Aug 2021 13:39:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F382D60FDA for ; Tue, 10 Aug 2021 13:39:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241650AbhHJNkO (ORCPT ); Tue, 10 Aug 2021 09:40:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:49392 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241877AbhHJNji (ORCPT ); Tue, 10 Aug 2021 09:39:38 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DD75E60EE7; Tue, 10 Aug 2021 13:38:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628602749; bh=fObxAgs+ulfRDwt7g5xTa8zsugCY1+6fJfkNM/IsNlA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=rL/ZttqfxsO2dZRUHtzy9nzwGGoLFagpqaqSVFKyYkmwEk8jLLj+VGms3FbxODWOE /axtGd5S9x+7lkyR5olgKW/uQ6xIG4FAyY22EBUvi0ygIQI/V8oqo0AztKG0xH8P+D i2BUBtwAKuoo5FiwRcNTvRRH5OPAvTRFsERhYmH3cPbkdyodLTyF6MqRFOB3VOotNS EgJsbqMLwqFLTVqbYkoNJRWhI2ATN7S7OajsyTWegqHLoNNk3q1brbNti/WGlP5hLq Dtva7zVz02U1F7tX/hFspZj7RsQEplXREoFsMoN28qsjq+2ZvBsJ6Dl4XjCpPfWmew qK1BAfDETIcpw== Date: Tue, 10 Aug 2021 15:38:40 +0200 From: Marek =?UTF-8?B?QmVow7pu?= To: Greg KH Cc: Ian Pilcher , hch@lst.de, axboe@kernel.dk, kernelnewbies@kernelnewbies.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, pavel@ucw.cz, pali@kernel.org, linux-leds@vger.kernel.org Subject: Re: [RFC PATCH v2 00/10] Add configurable block device LED triggers Message-ID: <20210810153840.42419d06@thinkpad> In-Reply-To: References: <20210809033217.1113444-1-arequipeno@gmail.com> <20210809205633.4300bbea@thinkpad> <81c128a1-c1b8-0f1e-a77b-6704bade26c0@gmail.com> <20210810004331.0f0094a5@thinkpad> <7b5f3509-5bcd-388b-8d3b-4ea95a9483ad@gmail.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org On Tue, 10 Aug 2021 08:35:08 +0200 Greg KH wrote: > On Mon, Aug 09, 2021 at 06:50:44PM -0500, Ian Pilcher wrote: > > On 8/9/21 5:43 PM, Marek Beh=C3=BAn wrote: =20 > > > I confess that I am not very familiar with internal blkdev API. =20 > >=20 > > It's mainly a matter of symbol visibility. See this thread from a few > > months ago: > >=20 > > https://www.spinics.net/lists/linux-leds/msg18244.html > >=20 > > Now ... my code currently lives in block/, so there isn't actually > > anything technically preventing it from iterating through the block > > devices. > >=20 > > The reactions to Enzo's patch (which you can see in that thread) make me > > think that anything that iterates through all block devices is likely to > > be rejected, but maybe I'm reading too much into it. > >=20 > >=20 > > Greg / Christoph - > >=20 > > (As you were the people who expressed disapproval of Enzo's patch to > > export block_class and disk_type ...) > >=20 > > Can you weigh in on the acceptability of iterating through the block > > devices (searching by name) from LED trigger code within the block > > subsystem (i.e. no new symbols would need to be exported)? > >=20 > > This would allow the trigger to implement the sysfs API that Marek and > > Pavel want. =20 >=20 > No idea, let's see the change first, we can never promise anything :) Hi Greg, Can't we use blkdev_get_by_path() (or blk_lookup_devt() with blkdev_get_by_dev())? This would open the block device and return a struct block_device *. When the LED trigger is disabled, it would also have to release the device. Marek