Compile freebsd kernel on linux

[Pratik Singhal]

Hello all , I am contributing to a project to FreeBSD kernel as a part of
Google summer of code 2015.

Unfortunately, my graphics card is not supported by the FreeBSD kernel and
therefore, I am unable to install FreeBSD on my system with basic Graphical
User Interface.  (only console mode is working)

I have to repeatedly compile FreeBSD current as a part of my my project. So
far, I have been using Virtualbox for running FreeBSD and for transferring
file b/w the Linux host and FreeBSD guest I used linuxdcpp application over
LAN. This process is quite cumbersome and takes a lot of valuable time.

I want to know is there any way in which I can compile freeBSD-current on
my Linux machine ?

Or is there any way in which I can share files b/w my Virtualbox guest and
Linux host. (The guest additions don't work I have tried many times) ?

Is there some other possible solution to my problem ?

Regards,
Pratik Singhal