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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 9E893C433E1 for ; Thu, 20 Aug 2020 13:12:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7811A22BEA for ; Thu, 20 Aug 2020 13:12:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597929143; bh=6Wt2/OLbFhN8zLqB45FFfmCoC7Jels6mZihiQFznnqI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=o+uTKQJCKBHnLIiWtHZet4rOMRX2kceKL6ubtTsMZBnYAsDZcban0wPxxaKaD1cak eFCUT16I6Ji3m1cKwHS3wrMxF0M1pATIhptZwk8Eo2hOO4zt35qH9BH9TP5/eGUTYf QrK7l+iRqhQQfnZE/X9SsF7mapb3H/Izpx8HfqBQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729671AbgHTNMB (ORCPT ); Thu, 20 Aug 2020 09:12:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:53402 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728712AbgHTJhR (ORCPT ); Thu, 20 Aug 2020 05:37:17 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 922E822B3F; Thu, 20 Aug 2020 09:37:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597916237; bh=6Wt2/OLbFhN8zLqB45FFfmCoC7Jels6mZihiQFznnqI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q51JtRMUjNlzQKcL4nRSmxWJbAJl8KwKVqauyWzLE/6XwsjkEyG6lcYeeGCArGVay /TvN1xKeTO4BvDc4aIejSfU0X2zQs4eGX56OvM/NuTCG9WoQs3J0XHhAbPNhPUtEo1 eu6lz8QOr5kfN7IrlpKLkrS14mlblc8J3sugC0JM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chris Murphy , Josef Bacik , David Sterba Subject: [PATCH 5.7 029/204] btrfs: dont show full path of bind mounts in subvol= Date: Thu, 20 Aug 2020 11:18:46 +0200 Message-Id: <20200820091607.716450842@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200820091606.194320503@linuxfoundation.org> References: <20200820091606.194320503@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josef Bacik commit 3ef3959b29c4a5bd65526ab310a1a18ae533172a upstream. Chris Murphy reported a problem where rpm ostree will bind mount a bunch of things for whatever voodoo it's doing. But when it does this /proc/mounts shows something like /dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0 /dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo/bar 0 0 Despite subvolid=256 being subvol=/foo. This is because we're just spitting out the dentry of the mount point, which in the case of bind mounts is the source path for the mountpoint. Instead we should spit out the path to the actual subvol. Fix this by looking up the name for the subvolid we have mounted. With this fix the same test looks like this /dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0 /dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo 0 0 Reported-by: Chris Murphy CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/super.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1310,6 +1310,7 @@ static int btrfs_show_options(struct seq { struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb); const char *compress_type; + const char *subvol_name; if (btrfs_test_opt(info, DEGRADED)) seq_puts(seq, ",degraded"); @@ -1396,8 +1397,13 @@ static int btrfs_show_options(struct seq seq_puts(seq, ",ref_verify"); seq_printf(seq, ",subvolid=%llu", BTRFS_I(d_inode(dentry))->root->root_key.objectid); - seq_puts(seq, ",subvol="); - seq_dentry(seq, dentry, " \t\n\\"); + subvol_name = btrfs_get_subvol_name_from_objectid(info, + BTRFS_I(d_inode(dentry))->root->root_key.objectid); + if (!IS_ERR(subvol_name)) { + seq_puts(seq, ",subvol="); + seq_escape(seq, subvol_name, " \t\n\\"); + kfree(subvol_name); + } return 0; }