tree 0734637651debfcf49ac8c20c8711a4924d131bd
parent fbc6feaec98ac0c6a615bbe9e17c5689a1a84650
author Nikolay Borisov <nborisov@suse.com> 1540910606 +0200
committer David Sterba <dsterba@suse.com> 1545054698 +0100

btrfs: add members to fs_devices to track fsid changes

In order to gracefully handle split-brain scenario during fsid change
(which are very unlikely, yet possible), two more pieces of information
will be necessary:

1. The highest generation number among all devices registered to a
   particular btrfs_fs_devices

2. A boolean flag whether a given btrfs_fs_devices was created by a
   device which had the FSID_CHANGING_V2 flag set.

This is a preparatory patch and just introduces the variables as well
as code which sets them, their actual use is going to happen in a later
patch.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>