Linux-ARM is a port of the rather wonderful Linux Operating System to the ARM processor. I've not done a huge amount specific to this port of Linux, but here's what is available.
IscaFS is a read-only ext2 image filing system for Acorn computers, which runs under their RISC OS operating system. It was written for the purpose of enabling users of linux-arm to read their ext2 partitions, floppy discs or image files under RISC OS.
I'd recommend checking on Marco Baye's web site for newer versions of IscaFS. I've not been developing IscaFS for many years now, and he's recently been doing a lot of work on it, fixing bugs and updating it to work on newer versions of RISC OS.
The following versions are currently available:
The first time I tried to install linux-arm, it was from a Clan Acorn CDROM. The CD was put together particularly badly, and was hell to install from, but I've written this installation guide which should help those wishing to install from this CDROM.
Of course, the Clan CD is now ancient history, and no doubt you should try out the newer distributions people have put together. I can't suggest which, since I've been out of the linux-ARM scene for some years now, but I'd suggest using this old chestnut only as a last resort.