4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Misono Tomohiro <misono.tomohiro@xxxxxxxxxxxxxx> [ 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 <misono.tomohiro@xxxxxxxxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/dev-replace.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -589,6 +589,12 @@ 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
