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=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 A1934C4320A for ; Tue, 10 Aug 2021 14:48:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86D7F60F02 for ; Tue, 10 Aug 2021 14:48:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241930AbhHJOse (ORCPT ); Tue, 10 Aug 2021 10:48:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:42436 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241888AbhHJOsb (ORCPT ); Tue, 10 Aug 2021 10:48:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4835560F25; Tue, 10 Aug 2021 14:48:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628606889; bh=BCaw6jsYR+1+ch9MuRv11DN73c0NzIIA0uUPkD5qS+Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aejb1GlEF8xfjZg3Dr67Ia/+4GKCFO8u3xGOqykZ1QOXFXvGioKaoWlknitlue5jy qP6VTMWyAJbbfpGq7Os9IMYLQhtpH92htrvSy6mCEvGJMjWoGnbD2YsYH5f7kgir9r XT4G8X93IOY/K4TixaZ117wv82K9ARjVLNNzBJ1g= Date: Tue, 10 Aug 2021 16:48:05 +0200 From: Greg KH To: Marek =?iso-8859-1?Q?Beh=FAn?= Cc: axboe@kernel.dk, kernelnewbies@kernelnewbies.org, Ian Pilcher , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, pavel@ucw.cz, pali@kernel.org, hch@lst.de, linux-leds@vger.kernel.org Subject: Re: [RFC PATCH v2 00/10] Add configurable block device LED triggers Message-ID: 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> <20210810153840.42419d06@thinkpad> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210810153840.42419d06@thinkpad> Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org On Tue, Aug 10, 2021 at 03:38:40PM +0200, Marek Behún wrote: > 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 Behún wrote: > > > > I confess that I am not very familiar with internal blkdev API. > > > > > > It's mainly a matter of symbol visibility. See this thread from a few > > > months ago: > > > > > > https://www.spinics.net/lists/linux-leds/msg18244.html > > > > > > Now ... my code currently lives in block/, so there isn't actually > > > anything technically preventing it from iterating through the block > > > devices. > > > > > > 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. > > > > > > > > > Greg / Christoph - > > > > > > (As you were the people who expressed disapproval of Enzo's patch to > > > export block_class and disk_type ...) > > > > > > 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)? > > > > > > This would allow the trigger to implement the sysfs API that Marek and > > > Pavel want. > > > > 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. But what about when the device is removed from the system first? Be careful about that... Anyway, sure, try those functions, I really do not know, all I originally complained about was those exports which did not need to be exported. thanks, greg k-h 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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 2B5D2C4338F for ; Tue, 10 Aug 2021 14:50:04 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 78EDC60F38 for ; Tue, 10 Aug 2021 14:50:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 78EDC60F38 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.94.2) (envelope-from ) id 1mDT4s-0007eq-Js for kernelnewbies@archiver.kernel.org; Tue, 10 Aug 2021 10:50:02 -0400 Received: from mail.kernel.org ([198.145.29.99]) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mDT35-0005ZI-AH for kernelnewbies@kernelnewbies.org; Tue, 10 Aug 2021 10:48:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4835560F25; Tue, 10 Aug 2021 14:48:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628606889; bh=BCaw6jsYR+1+ch9MuRv11DN73c0NzIIA0uUPkD5qS+Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aejb1GlEF8xfjZg3Dr67Ia/+4GKCFO8u3xGOqykZ1QOXFXvGioKaoWlknitlue5jy qP6VTMWyAJbbfpGq7Os9IMYLQhtpH92htrvSy6mCEvGJMjWoGnbD2YsYH5f7kgir9r XT4G8X93IOY/K4TixaZ117wv82K9ARjVLNNzBJ1g= Date: Tue, 10 Aug 2021 16:48:05 +0200 From: Greg KH To: Marek =?iso-8859-1?Q?Beh=FAn?= Subject: Re: [RFC PATCH v2 00/10] Add configurable block device LED triggers Message-ID: 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> <20210810153840.42419d06@thinkpad> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210810153840.42419d06@thinkpad> Cc: axboe@kernel.dk, kernelnewbies@kernelnewbies.org, Ian Pilcher , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, pavel@ucw.cz, pali@kernel.org, hch@lst.de, linux-leds@vger.kernel.org X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: kernelnewbies-bounces+kernelnewbies=archiver.kernel.org@kernelnewbies.org On Tue, Aug 10, 2021 at 03:38:40PM +0200, Marek Beh=FAn wrote: > 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=FAn wrote: = > > > > I confess that I am not very familiar with internal blkdev API. = > > > = > > > It's mainly a matter of symbol visibility. See this thread from a few > > > months ago: > > > = > > > https://www.spinics.net/lists/linux-leds/msg18244.html > > > = > > > Now ... my code currently lives in block/, so there isn't actually > > > anything technically preventing it from iterating through the block > > > devices. > > > = > > > 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. > > > = > > > = > > > Greg / Christoph - > > > = > > > (As you were the people who expressed disapproval of Enzo's patch to > > > export block_class and disk_type ...) > > > = > > > 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)? > > > = > > > This would allow the trigger to implement the sysfs API that Marek and > > > Pavel want. = > > = > > 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. But what about when the device is removed from the system first? Be careful about that... Anyway, sure, try those functions, I really do not know, all I originally complained about was those exports which did not need to be exported. thanks, greg k-h _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies