btrfs: replace: Reset on-disk dev stats value after replace
authorMisono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Tue, 31 Jul 2018 07:20:21 +0000 (16:20 +0900)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 15 Sep 2018 07:43:00 +0000 (09:43 +0200)
commite22b36a336fa637efb8f2d52fe1a8ebbd2cb1f57
tree57abcaa461cc6b46ac1f3710d5a72f4e27f10f29
parent4678c00e9dd5f246ea1078912e9564b9e938400a
btrfs: replace: Reset on-disk dev stats value after replace

[ 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@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/btrfs/dev-replace.c