gaul/mirrorfs

Mirror filesystem operations and check for consistency

mirrorfs

A FUSE filesystem that mirrors operations and checks for consistency. mirrorfs ensures that the results of operations are exactly the same, e.g., system call results, errnos, stat structs, read buffers. This can help test an in-development filesystem against a known good one, e.g., ext4.

Usage

On Fedora, install dependencies via:

sudo dnf install fuse3 fuse3-devel fuse3-libs

Build via make then run via:

./mirrorfs GOOD_PATH TESTING_PATH MOUNT_PATH

If you provide the -f option mirrorfs will start in the foreground and log its operations. Now programs can interact with MOUNT_PATH as usual. When mirrorfs detects an inconsistency it will log the diverging result and abort.

License

Copyright (C) 2019 Andrew Gaul

Licensed under the MIT License

mirrorfs's Issues

compare readdir struct stat

Currently mirrorfs_readdir only returns the results from the first mount point. Instead it should compare results from both mount points. Since the mount points can returns results in different orders this requires some extra logic to reconcile.