[ubuntu] 14.04 mdadm + bcache with an SSD? topic

Hi everyone,
i have a Lenovo P300 Workstation configured with Ubuntu 14.04 LTS 64 bit and working with the following configuration:
-/dev/sda 2tb hdd, /dev/sda1 /boot, /dev/sda2 /swap, /dev/sda3 / - part of raid
-/dev/sdb 2tb hdd, /dev/sda1 unused, /dev/sda2 /swap, /dev/sda3 / - part of raid


I've also bought a 256GB SSD, /dev/sdc.
I'm trying to find if it's possible to configure this SSD as cache of the root "/" partition /dev/md0, that is a raid 1 software with mdadm! Any ideas or link for me? Google isn't helping... : (


Thanks in advance