From patchwork Mon Aug 24 08:30:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 265094 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 EEE31C433E3 for ; Mon, 24 Aug 2020 09:21:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CED212074D for ; Mon, 24 Aug 2020 09:21:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598260911; bh=z4RrUhXdi5Lxki7P+0zJ3b9PeHj/1dUS7LD1cFnynYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jv0LtC3G/kXpaTttFevk8USi1i83nNFD9Zp59J10zJVYRSf9/Il4U95T53R5evxC/ 2ykPn0w4ns2vIEH92JDTiV/2oc1GvP38Bzbw+o5+b9oFsjRLxGG0tC3lWl6QY+ZCOY EhJPv05dB9X5FAqR818Y7YorDCfDwttit18I3eik= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728740AbgHXJVu (ORCPT ); Mon, 24 Aug 2020 05:21:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:38050 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729949AbgHXIzk (ORCPT ); Mon, 24 Aug 2020 04:55:40 -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 69288206F0; Mon, 24 Aug 2020 08:55:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598259340; bh=z4RrUhXdi5Lxki7P+0zJ3b9PeHj/1dUS7LD1cFnynYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fB/P01T8HsGAf47WBtIGLd8tOET2bwDbPriQjNuPzYFsUl3RDWmmOTvKljFn8Hh2S NiZPF4dWadlu953tOLe/yXXpRQdUqMxrWfcKyD8CSHUH8TyxB+zwzehyyKtkB/fUR3 D4qhiaiArrn7HsbGcIRagNkyDdoavBvI/FJ5YIwg= 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 4.19 06/71] btrfs: dont show full path of bind mounts in subvol= Date: Mon, 24 Aug 2020 10:30:57 +0200 Message-Id: <20200824082356.190913402@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200824082355.848475917@linuxfoundation.org> References: <20200824082355.848475917@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 3e6e21a7c5e6f..4d2810a32b4a9 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1282,6 +1282,7 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) { 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"); @@ -1366,8 +1367,13 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) 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; }