Convert ext2/3/4 and ReiserFS file systems to Btrfs without data loss

If you want to convert your system partition you'll need to perform these steps from another operating system like the RebornOS live ISO.

1. Find out the device name of the partition you want to convert to Btrfs. lsblk, fdisk -l or a graphical partition manager are good ways to find the device name of the partition you want to convert.

2. If the partition is mounted, unmount it: sudo umount /dev/<device name of partition>

3. Run sudo fsck -fy /dev/<device name of partition> to check the file system for inconsistencies.

4. If no problems were found run sudo btrfs-convert /dev/<device name of partition> to convert the file system to Btrfs. If no errors occurred the file system should be Btrfs now.

5. If the new Btrfs partition is a system partition make sure to mount it (sudo mount /dev/<device name of partition> /mnt) and edit the systems fstab (sudo nano /mnt/etc/fstab) to accommodate for the change before rebooting.