[RFC] Should we consider to re-write HFS/HFS+ in Rust?

[Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>]

Hi Adrian, Yangtao,

One idea crossed my mind recently. And this is about re-writing HFS/HFS+ in
Rust. It could be interesting direction but I am not sure how reasonable it
could be. From one point of view, HFS/HFS+ are not critical subsystems and we
can afford some experiments. From another point of view, we have enough issues
in the HFS/HFS+ code and, maybe, re-working HFS/HFS+ can make the code more
stable.

I don't think that it's a good idea to implement the complete re-writing of the
whole driver at once. However, we need a some unification and generalization of
HFS/HFS+ code patterns in the form of re-usable code by both drivers. This re-
usable code can be represented as by C code as by Rust code. And we can
introduce this generalized code in the form of C and Rust at the same time. So,
we can re-write HFS/HFS+ code gradually step by step. My point here that we
could have C code and Rust code for generalized functionality of HFS/HFS+ and
Kconfig would define which code will be compiled and used, finally.

How do you feel about this? And can we afford such implementation efforts?

Thanks,
Slava.