From patchwork Sat Feb 9 04:52:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 10804095 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 598EC922 for ; Sat, 9 Feb 2019 04:53:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 49F502DCB3 for ; Sat, 9 Feb 2019 04:53:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3E1D82DCDB; Sat, 9 Feb 2019 04:53:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D5BD42DCB3 for ; Sat, 9 Feb 2019 04:53:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726791AbfBIEx3 (ORCPT ); Fri, 8 Feb 2019 23:53:29 -0500 Received: from mx2.suse.de ([195.135.220.15]:57592 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726222AbfBIEx3 (ORCPT ); Fri, 8 Feb 2019 23:53:29 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 1BA79AFB8; Sat, 9 Feb 2019 04:53:28 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH 03/19] bcache: export backing_dev_name via sysfs Date: Sat, 9 Feb 2019 12:52:55 +0800 Message-Id: <20190209045311.15677-4-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190209045311.15677-1-colyli@suse.de> References: <20190209045311.15677-1-colyli@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch export dc->backing_dev_name to sysfs file /sys/block/bcache/bcache/backing_dev_name, then people or user space tools may know the backing device name of this bcache device. Of cause it can be done by parsing sysfs links, but this method can be much simpler to find the link between bcache device and backing device. Signed-off-by: Coly Li --- drivers/md/bcache/sysfs.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 557a8a3270a1..b9166ee027fa 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -67,6 +67,7 @@ read_attribute(written); read_attribute(btree_written); read_attribute(metadata_written); read_attribute(active_journal_entries); +read_attribute(backing_dev_name); sysfs_time_stats_attribute(btree_gc, sec, ms); sysfs_time_stats_attribute(btree_split, sec, us); @@ -243,6 +244,12 @@ SHOW(__bch_cached_dev) return strlen(buf); } + if (attr == &sysfs_backing_dev_name) { + snprintf(buf, BDEVNAME_SIZE + 1, "%s", dc->backing_dev_name); + strcat(buf, "\n"); + return strlen(buf); + } + #undef var return 0; } @@ -452,6 +459,7 @@ static struct attribute *bch_cached_dev_files[] = { &sysfs_verify, &sysfs_bypass_torture_test, #endif + &sysfs_backing_dev_name, NULL }; KTYPE(bch_cached_dev);