Re: [RFC PATCH 0/10] ftrfs: Fault-Tolerant Radiation-Robust Filesystem

[Matthew Wilcox]

On Mon, Apr 13, 2026 at 04:23:46PM +0200, Aurelien DESBRIERES wrote:
> FTRFS was originally described in:
> 
>   Fuchs, C.M., Langer, M., Trinitis, C. (2015).
>   FTRFS: A Fault-Tolerant Radiation-Robust Filesystem for Space Use.
>   ARCS 2015, LNCS vol 9017, Springer.
>   https://doi.org/10.1007/978-3-319-16086-3_8

Might be nice to link to a non-paywalled copy of that paper, eg:

https://www.cfuchs.net/chris/publication-list/ARCS2015/FTRFS.pdf

> This implementation is an independent open-source realization of the
> concepts described in that paper, developed for the Linux kernel.

Can I ask why?  Is the original code not available or too ugly?

> On-disk layout:
> 
>   Block 0        : superblock (magic 0x46545246, CRC32-protected)
>   Block 1..N     : inode table (128 bytes/inode, CRC32 per inode)
>   Block N+1..end : data blocks (CRC32 + RS FEC per block)
> 
> Inodes use direct addressing (12 direct block pointers) plus single
> and double indirection. Directory entries are fixed-size (268 bytes)
> stored in direct blocks.

This is very old-school.  That may be appropriate for the intended
use-case, but it ignores about five decades of filesystem research.