From patchwork Mon Aug 24 08:31:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 265088 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=-13.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, 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 68F1CC433E3 for ; Mon, 24 Aug 2020 09:23:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49B242074D for ; Mon, 24 Aug 2020 09:23:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598260985; bh=guEBnYs7vYaGJWWSLALjN97mlt8HGTIaUiWnp2CCR4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UkgyglLkX0y9SfVR2cuS+SELYWsCSGxftoQBWfsIfvxiPgTK4Lttdw8i5r7OHd1rZ 8vYJsdbtUp1yvIwEMawh1xsI/lnjBrR4iMg5xmhOD7/Z0AaZv2L0M6dzAmLwFEIQT5 8XVoh7Xso8O6dEcsyLN0JqZjBXXKpeZ42SPkuddw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726189AbgHXJXE (ORCPT ); Mon, 24 Aug 2020 05:23:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:35378 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730343AbgHXIyg (ORCPT ); Mon, 24 Aug 2020 04:54:36 -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 A5BC7204FD; Mon, 24 Aug 2020 08:54:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598259276; bh=guEBnYs7vYaGJWWSLALjN97mlt8HGTIaUiWnp2CCR4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BEnqC0FGjgcndl4dv2/NegHpQSJeHiVuFFQR7eKLhFPzqi/uQiaaX5+BKO7K1cdbm o5oGW/piJIGvPUcHFxfkdP8n9WwzQLFcWsVvY6xEA9rT9dM5XHqTgUbUia+Lq/M8SV USW6tucz3UHcjVcbTHCImnOTA08pt5w5spWUOprw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chris Murphy , Josef Bacik , David Sterba , Sasha Levin Subject: [PATCH 4.14 08/50] btrfs: dont show full path of bind mounts in subvol= Date: Mon, 24 Aug 2020 10:31:09 +0200 Message-Id: <20200824082352.319650562@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200824082351.823243923@linuxfoundation.org> References: <20200824082351.823243923@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Josef Bacik [ Upstream commit 3ef3959b29c4a5bd65526ab310a1a18ae533172a ] 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: Sasha Levin --- fs/btrfs/super.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index ca95e57b60ee1..eb64d4b159e07 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1221,6 +1221,7 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) { struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb); char *compress_type; + const char *subvol_name; if (btrfs_test_opt(info, DEGRADED)) seq_puts(seq, ",degraded"); @@ -1307,8 +1308,13 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) #endif 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; }