Wedson Almeida Filho from Microsoft proposed for discussion on the Linux kernel developers' mailing list the second version of patches with a set of wrappers for the VFS subsystem, aimed at developing read-only file systems in Rust. Along with the wrappers, two drivers based on them implementing the ext2 and tarfs file systems in read-only mode have been published. Unlike the previously available Rust implementation of the ext2 filesystem — ext2-rs, the new variant operates at the kernel level (module rust_ext2), rather than in user space. The rust_ext2 driver contains about 700 lines of Rust code and can serve as a starting point for developing more complex filesystem implementations, such as Ext4.
The tarfs file system allows mounting archives in Tar format as a file system. The driver uses an index attached to the tar files for navigating files within the archive without having to scan the entire contents.
Another filesystem developed in Rust that uses the proposed abstraction layer is PuzzleFS. PuzzleFS is designed for hosting isolated containers and features capabilities such as efficient storage of duplicate data, the ability to mount directly, repeatable image builds, very fast image assembly and mounting, the option of using an optional intermediate stage for image canonicalization, the non-requirement for full passes through the filesystem tree when using a layered structure, and changes overlay in a casync style.
Source: opennet.ru
