Eventually I have converted root-fs into bcache (with the help of
blocks). I skipped the step
update-initramfs -u -k all because I've been using bcache on other partitions for some time, and I've wrongly assumed, that the appropriate kernel module must have been in the initramfs already.
The system doesn't boot; instead it shows me the initramfs prompt, and I cannot see bcache neither on
/sys/fs/bcache nor on
cat /proc/modules; so I assume that the module is loaded on the later stages.
Normally I'd boot into liveCD and rebuild the initramfs from there with the
chroot trick. Unfortunately I know no Linux live CD with bcache support, so I have no hope of mounting the root partition other way, than buing new hard drive and installing a Linux there so it can be a platfrom for repairing the main Linux... And playing with two Linux installations would take a lot of extra time and addtitional risk that I might screw another thing up.
Is there anything I can do without buing a new hard drive? Maybe someone know a liveCD that supports bcache?
I use Linux Mint Cinnamon 16 64bit with separate boot partition.
The installation of
bcache-tools from the "official"
bcache ppa:g2p/storage does indeed install the required
bcache modules. Except that if you have more then 1 kernel on /boot it applies it only to the most recent kernel. In my case I had two kernels: 3.11 from official the Ubuntu Saucy sources, and second mainline kernel 3.12 (which isn't compatible with Cinnamon 2.0 somehow). Only the 3.12 kernel got the bcache module included in the initramfs.