Bcachefs on Guix

At least until 2024-11-10, Guix support for bcachefs is not optimal.

I patched Guix for supporting multi-device specifications.

I mount the file-system in this way:

  (file-systems (cons*
          (file-system
             (mount-point "/")
             (device (uuid "c1b801d4-ab86-4e62-b0d2-f8ef7d424879"))
             (type "btrfs")
             (options "compress=zstd"))

          (file-system
             (mount-point "/mnt/bcachefs")
             (type "bcachefs")
             (device "/dev/sdb:/dev/sdc:/dev/sdd")
             (mount-may-fail? #t) ; TODO temporary hack, otherwise the Guix boot process can be blocked in case of errors on some device
             (options "degraded") ; accept also recoverable errors,
                                  ; otherwise the system is blocked
          )

          %base-file-systems)))

bcachefs on root file-system is not yet supported, so I use btrfs;
the boot process in Guix must read the gnu store, that it is on btrfs;
I created symbolic links from the root btrfs file-system to the bcachefs file-system mounted on /mnt/bcachefs, e.g. /home, /srv, /var/opt;
I didn’t touched system directory needed at boot, like /var/lib;
I disabled the calling of bcachefs fsck from bcachefs-tools, because it is automatically done from the kernel bcachefs, and there can be mismatch between the versions of the two;