4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Misono Tomohiro <misono.tomoh...@jp.fujitsu.com>
[ 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.tomoh...@jp.fujitsu.com>
Reviewed-by: David Sterba <dste...@suse.com>
Signed-off-by: David Sterba <dste...@suse.com>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
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
