====== XFS FUSE Implementation ======

  * Student: [[/KhaledEmara|KhaledEmara]] (<mail@KhaledEmara.dev>)
  * Mentors: [[/AlanSomers|AlanSomers]] and [[/PedroGiffuni|PedroGiffuni]]

===== Project Description =====

This project is part of %%GSoC%%'21. In this project, I've worked on a read-only userland
implementation of the XFS Filesystem through the FUSE kernel interface. This involved
writing the client in Rust using the [[https://docs.rs/fuse/0.3.1/fuse/|fuse crate]].

===== Deliverables =====

  * XFS library.
    * Read basic structures such as the Super Block and the AGI.
    * Parse Extents.
    * Parse and Navigate variable-length B+Trees.
    * Parse and Navigate fixed-length B+Trees.
    * Read and Traverse directories:
      * Short Form directories.
      * Block directories.
      * Leaf directories.
      * Node directories.
      * B+Tree directories.
    * Read files:
      * Extent-based files.
      * B+Tree-based files.
    * Read symbolic links:
      * Short Form symbolic links.
      * Extent-based symbolic links.
    * Read extended attributes:
      * Short Form extended attributes.
      * Leaf extended attributes.
      * Node extended attributes.
      * B+Tree extended attributes.
  * FUSE glue code.
    * stat the filesystem.
    * Access control.
    * Return standard Unix file attributes.
    * Both stateless directories and with state files implementations.
  * Some Unit Tests.
  * Metadata integrity checks.
    * CRC32C check.
    * UUID checks.
    * Magic Number checks.
    * Block Number checks.
  * %%FreeBSD%% Ports package.

===== Test Plan =====

Some unit tests have been written, but the coverage is weak. The coverage could be
expanded as a future plan. I have also tested the filesystem manually and verified each
functionality.

===== Weekly Progress =====

^  Wiki Entry  ^
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week10|Week 10]] |
| [[/Week9|Week 9]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week8|Week 8]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week7|Week 7]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week6|Week 6]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week5|Week 5]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week4|Week 4]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week3|Week 3]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week2|Week 2]] |
| [[SummerOfCode2021Projects/XFSFUSEImplementation/Week1|Week 1]] |

===== The Code =====

  * [[https://github.com/KhaledEmaraDev/xfuse|GitHub]]
  * {{summerofcode2021projects/xfsfuseimplementation/package.diff?linkonly|Ports Package Patch File (.diff)}}

The code was maintained in a [[/GitHub|GitHub]] repo that I own. Patches were usually pushed
directly to the main branch. I included a little bit of documentation on how to run the
project, how it's structured, and how to start contributing to it in the README.md and
CONTRIBUTING.md files. I also included a man page as a documentation on how to use.
Finally, I have included a License that is compatible with %%FreeBSD%%. Code was written
from scratch in this repo. All the project's target were met.

I have attached a patch file to create the necessary files in order to create a %%FreeBSD%%
ports package.

===== What Lies Ahead =====

I think first and foremost I have test again and again and iron out all the bugs if
found. Secondly, I have to refactor the code for better readability and performance.
Finally and as for additional features, we could add journal logs support or add write
support, although the latter would be a huge undertaking.

----

{{tag>Gsoc}}