* Paolo Bonzini (pbonz...@redhat.com) wrote: > On 22/05/19 14:53, Stefan Hajnoczi wrote: > > On Tue, May 21, 2019 at 03:39:40PM +0100, Peter Maydell wrote: > >> Hi; I have on my todo list the idea of some experimentation/prototyping > >> of whether being able to write some components of QEMU in Rust would > >> be (a) feasible (b) beneficial (c) fun to play around with even if > >> it is likely that it doesn't go anywhere :-) > >> > >> I know Paolo has had a look at how you might write some makefiles > >> to integrate rust into a C program > >> (https://github.com/bonzini/rust-and-c/). > >> Has anybody else been doing anything in this general area ? > >> > >> (I went to two good talks locally recently about rust-vmm and Amazon's > >> 'firecracker' VMM by Andreea Florescu and Diana Popa -- I > >> definitely plan to look at rust-vmm as part of this.) > > > > There are some in-development vhost-user device backends in Rust. > > Sergio Lopez is working on a vhost-user-blk implementation. David > > Gilbert is working on a vhost-user-fs implementation. > > > > I think mixing Rust and C code in the main QEMU binary itself is > > probably more trouble than it's worth. Think boilerplate, duplication, > > coming up with safe Rust APIs for QEMU's unsafe APIs. > > This is true. The case I was playing with is where the QEMU APIs have a > more or less direct mapping to rust-vmm APIs and only have a limited > number of dependencies on other C APIs. This way, you can either write > a Rust binding to the C code, or rewrite the C code in Rust with tiny C > wrapper APIs on top. > > For example, the memory API (more or less) depends only on RCU and maps > to rust-vmm/vm-memory, and virtqueue processing in rust-vmm/vm-virtio > depends only on the memory API.
The other place might be places where we're autogenerating the C interfaces anyway - e.g. we could autogenerate rust bindings for qapi. Dave > Thanks, > > Paolo > > > I'm more interested in using Rust for separate processes that can be > > written from scratch. > > > > Stefan > > > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
