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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0BC13C636CC for ; Mon, 13 Feb 2023 14:56:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230088AbjBMO4n (ORCPT ); Mon, 13 Feb 2023 09:56:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229597AbjBMO4N (ORCPT ); Mon, 13 Feb 2023 09:56:13 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 60C111CF62 for ; Mon, 13 Feb 2023 06:55:54 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B423F6113A for ; Mon, 13 Feb 2023 14:55:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C88E3C433D2; Mon, 13 Feb 2023 14:55:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1676300153; bh=Xn2s9b9zvceMPwGSnwMVIypGjOYtD7ureubCOqCepBo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O7uvSJbxazhT4TjI0CoOSxaVediylsy39R662oZgGpkg6src5Ufy5yooIfg8b1vcX o9jWNbhw1rPNc40+qb2nL3il+ogfMLeZWEKqnKntGWPeCSAcXDalf4seuNGiY4JI1W XA9haiyAk8Tl5eQBEYVTwvXxSkiYuUrTnvmnWBCM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daan De Meyer , Josef Bacik , Anand Jain , David Sterba Subject: [PATCH 6.1 084/114] btrfs: free device in btrfs_close_devices for a single device filesystem Date: Mon, 13 Feb 2023 15:48:39 +0100 Message-Id: <20230213144746.501714669@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230213144742.219399167@linuxfoundation.org> References: <20230213144742.219399167@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Anand Jain commit 5f58d783fd7823b2c2d5954d1126e702f94bfc4c upstream. We have this check to make sure we don't accidentally add older devices that may have disappeared and re-appeared with an older generation from being added to an fs_devices (such as a replace source device). This makes sense, we don't want stale disks in our file system. However for single disks this doesn't really make sense. I've seen this in testing, but I was provided a reproducer from a project that builds btrfs images on loopback devices. The loopback device gets cached with the new generation, and then if it is re-used to generate a new file system we'll fail to mount it because the new fs is "older" than what we have in cache. Fix this by freeing the cache when closing the device for a single device filesystem. This will ensure that the mount command passed device path is scanned successfully during the next mount. CC: stable@vger.kernel.org # 5.10+ Reported-by: Daan De Meyer Signed-off-by: Josef Bacik Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/volumes.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -408,6 +408,7 @@ void btrfs_free_device(struct btrfs_devi static void free_fs_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device; + WARN_ON(fs_devices->opened); while (!list_empty(&fs_devices->devices)) { device = list_entry(fs_devices->devices.next, @@ -1194,9 +1195,22 @@ void btrfs_close_devices(struct btrfs_fs mutex_lock(&uuid_mutex); close_fs_devices(fs_devices); - if (!fs_devices->opened) + if (!fs_devices->opened) { list_splice_init(&fs_devices->seed_list, &list); + /* + * If the struct btrfs_fs_devices is not assembled with any + * other device, it can be re-initialized during the next mount + * without the needing device-scan step. Therefore, it can be + * fully freed. + */ + if (fs_devices->num_devices == 1) { + list_del(&fs_devices->fs_list); + free_fs_devices(fs_devices); + } + } + + list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) { close_fs_devices(fs_devices); list_del(&fs_devices->seed_list);