F2FS File-System Adding Support For IDMAPPED Mounts

Linux 5.12 introduced support for IDMAPPED mounts with a variety of use-cases from containers to systemd-homed usage. The Flash-Friendly File-System (F2FS) is now the latest Linux file-system preparing to support the feature.

IDMAPPED mounts allow for different mounts to expose the same file or directory with different ownership. IDMAPPED mounts in Linux 5.12 originally supported EXT4 and FAT while since then other file-systems have begun supporting it, like Btrfs. More details on IDMAPPED mounts via the kernel docs.

F2FS has been working on IDMAPPED mounts support and queued up their initial implementation within the file-systems "dev" branch. If all goes well, that F2FS IDMAPPED support would then be found in the v5.18 kernel in a few months.

It's just a few dozen lines of code for F2FS to support IDMAPPED mounts with all the details being laid out via this F2FS "dev" patch.