Re: [PATCH 1/7] rust: file: add Rust abstraction for `struct file`

[Peter Zijlstra]

On Wed, Nov 29, 2023 at 03:13:22PM +0000, Matthew Wilcox wrote:

> > @@ -157,6 +158,12 @@ void rust_helper_init_work_with_key(struct work_struct *work, work_func_t func,
> >  }
> >  EXPORT_SYMBOL_GPL(rust_helper_init_work_with_key);
> >  
> > +struct file *rust_helper_get_file(struct file *f)
> > +{
> > +	return get_file(f);
> > +}
> > +EXPORT_SYMBOL_GPL(rust_helper_get_file);
> 
> This is ridiculous.  A function call instead of doing the
> atomic_long_inc() in Rust?

Yeah, I complained about something similar a while ago. And recently
talked to Boqun about this as well,

Bindgen *could* in theory 'compile' the inline C headers into (unsafe)
Rust, the immediate problem is that Rust has a wildly different inline
asm syntax (because Rust needs terrible syntax or whatever).

Boqun said it should all be fixable, but is a non-trivial amount of
work.