Re: Libublk-rs v0.1.0

[Gabriel Krisman Bertazi <krisman@suse.de>]

Ming Lei <ming.lei@redhat.com> writes:

> Hello,
>
> Libublk-rs(Rust)[1][2] 0.1.0 is released.

Hi Ming,

Do you intend to effectively deprecate the code in ubdsrv in favor of
libublk-rs or do you intend to keep the C library?  I'm asking because
I'm looking into how to enable ublk in distributions.

Thanks,

>
> The original idea is to use Rust to write ublk target for covering all
> kinds of block queue limits/parameters combination easily when talking
> with Andreas and Shinichiro about blktests in LSFMM/BPF 2023.
>
> Finally it is evolved into one generic library. Attributed to Rust's
> some modern language features, libublk interfaces are pretty simple:
>
> - one closure(tgt_init) for user to customize device by providing all
>   kind of parameter
>
> - the other closure(io handling) for user to handling IO which is
>   completely io_uring CQE driven: a) IO command CQE from ublk driver,
>   b) target IO CQE originated from target io handling code, c) eventfd
>   CQE if IO is offloaded to other context
>
> With low level APIs, <50 LoC can build one ublk-null, and if high level
> APIs are used, 30 LoC is enough.
>
> Performance is basically aligned with pure C ublk implementation[3].
>
> The library has been verified on null, ramdisk, loop and zoned target.
> The plan is to support async/await in 0.2 or 0.3 so that libublk can
> be used to build complicated target easily and efficiently.
>
> Thanks Andreas for reviewing and providing lots of good ideas for
> improvement & cleanup. Thanks German Maglione for some suggestions, such
> as eventfd support. Thanks Joe for providing excellent Rust programming
> guide.
>
> Any feedback is welcome!
>
> [1] https://crates.io/crates/libublk 
> [2] https://github.com/ming1/libublk-rs
> [3] https://github.com/osandov/blktests/blob/master/src/miniublk.c
>
> Thanks,
> Ming
>

-- 
Gabriel Krisman Bertazi