add possibility to add list of dirs to mount for php

[yosefy]

to disable option for application to create link to another application's dir on same server, and more security stuff
i would like to be able to chroot the app but give it read permissions for specific dirs (for php needs) only (mount it to chroot)
i mean to add it in unit config
like /var/lib/, /etc/php-fpm/ for example
for now it is chroot all or nothing for php
what do you think?
thanks