Occasionally there may be the need for a user to build a vfs module.
Actually, this task is complicated by the fact that includes constituting the "VFS api" are somehow buried into the whole samba source package, so that the user has to identify the set of include files needed to recompile its module each time a new release of the samba package ships.
I would suggest to open the module model and the VFS api as a whole to outside world, allowing users to not have to rely on a release-dependent include tree for this, but instead to a well defined set of include, possibly installed in a FHS-compliant directory (/usr/include/samba, in example).
not saying that this is a bad idea, even the steps to add a vfs module inside the samba build tree isn't simple. If you want to propose a patch, please do.
As we will sooner or later move to a waf based build approach by default however we will probably not put much effert into this now.
Closing as WONTFIX, feel free to reopen if you have a patch to propose.