possible confusion in documentation regarding paths/mountpoints

[Termuellinator]

First of all - thanks for this project :)

I've just set it up and for an initial baseline i ran the defrag, balance and scrub scripts. In the config file i've set / and /home to be scrubbed, which are subvolumes on the same btrfs partiton.

sudo btrfs scrub status / now returns the exact same output as sudo btrfs scrub status /home - thus making the impression that scrub is run across all subvolumes and not just the provided mountpoint. I couldn't find anything about that in the btrfs documentation though so i thought i'd post it here.

For BTRFS_DEFRAG_PATHS it is explicitly mentioned that it doesn't cross mountpoints, for BTRFS_BALANCE_MOUNTPOINTS and BTRFS_SCRUB_MOUNTPOINTS it isn't 100% clear to me if it does or not.
As i've assumed the "does not cross" rule applies to all settings, balance and scrub is run multiple times.

Now that i look at it, the differentiation between _PATHS and _MOUNTPOINTS kind of indicates this, but maybe it would be good to include a hint to that in the comments for the respecting settings? Or am i totally wrong with my conclusion that scrub and balance cross subvolumes?