README

This repository contains the research prototype for the RFSCK project and the following publications:

• "Towards Robust File System Checkers", Om R. Gatla, Mai Zheng, Muhammad Hameed, Viacheslav Dubeyko, Adam Manzanares, Filip Blagojevic, Cyril Guyot, and Robert Mateescu, ACM Transactions on Storage (TOS), Volume 14 Issue 4, 2018. [Invited]

• "Towards Robust File System Checkers", Om R. Gatla, Muhammad Hameed, Mai Zheng, Viacheslav Dubeyko, Adam Manzanares, Filip Blagojevic, Cyril Guyot, and Robert Mateescu. Proceedings of the 16th USENIX Conference on File and Storage Technologies (FAST), 2018. [Best Paper Nominee]

• "Understanding the Fault Resilience of File System Checkers", Om R. Gatla and Mai Zheng, Proceedings of the 9th USENIX Workshop on Hot Topics in Storage and File Systems (HotStorage), 2017.

rfsck-lib: Generic Redo Log Library

This repository consists of the source code for a generic redo log, which can be easily integrated to existing file system checkers to provide logging mechanism and make them fault resilient. We have published our paper titled "Towards Robust File System Checkers" at FAST'18, and it contains detailed information about the analysis and implementation of rfsck-lib. [Paper PDF]

In addition to the source code we also provide the following prototypes in this repo:

1. rfsck-ext is an example of how we integrated rfsck-lib with e2fsck. The source files of the log file are copied into the folder rfsck-ext/lib/ext2fs/. Then redo.h is imported into various header files.

   A grep on the function names would show you how we have integrated rfsck-lib with e2fsck.

   In this example we have provided safe transactions for all the updates in each pass.

2. rfsck-xfs is an example of how we integrated rfsck-lib with xfs_repair. Similar to rfsck-ext, we have copied the redo log files to folder rfsck-ext/xfslib/, and then included redo.h into various header files.

   In this example we consider updates of the entire run of xfs_repair as one transaction

3. e2fsck-patch is a simple fix to make e2fsck robust. To achieve this, we synchronize the updates to the undo log.

rfsck-test: Fault Injection Framework

To test the resilience of rfsck-lib, we use a fault injection framework that records iSCSI commands to the block device and replays prefix commands back to the device to emulate fault.

Contact

Om R. Gatla (ogatla@iastate.edu), Duo Zhang (duozhang@iastate.edu).