From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:34954 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727760AbeIMTKZ (ORCPT ); Thu, 13 Sep 2018 15:10:25 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Misono Tomohiro , David Sterba , Sasha Levin Subject: [PATCH 4.18 134/197] btrfs: replace: Reset on-disk dev stats value after replace Date: Thu, 13 Sep 2018 15:31:23 +0200 Message-Id: <20180913131846.920472528@linuxfoundation.org> In-Reply-To: <20180913131841.568116777@linuxfoundation.org> References: <20180913131841.568116777@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Misono Tomohiro [ Upstream commit 1e7e1f9e3aba00c9b9c323bfeeddafe69ff21ff6 ] on-disk devs stats value is updated in btrfs_run_dev_stats(), which is called during commit transaction, if device->dev_stats_ccnt is not zero. Since current replace operation does not touch dev_stats_ccnt, on-disk dev stats value is not updated. Therefore "btrfs device stats" may return old device's value after umount/mount (Example: See "btrfs ins dump-t -t DEV $DEV" after btrfs/100 finish). Fix this by just incrementing dev_stats_ccnt in btrfs_dev_replace_finishing() when replace is succeeded and this will update the values. Signed-off-by: Misono Tomohiro Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/dev-replace.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -677,6 +677,12 @@ static int btrfs_dev_replace_finishing(s btrfs_rm_dev_replace_unblocked(fs_info); /* + * Increment dev_stats_ccnt so that btrfs_run_dev_stats() will + * update on-disk dev stats value during commit transaction + */ + atomic_inc(&tgt_device->dev_stats_ccnt); + + /* * this is again a consistent state where no dev_replace procedure * is running, the target device is part of the filesystem, the * source device is not part of the filesystem anymore and its 1st