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Date:   Mon, 11 Dec 2023 15:34:26 +0000
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Message-ID: <20231211153426.4161159-1-aliceryhl@google.com>
Subject: Re: [PATCH v2 2/7] rust: cred: add Rust abstraction for `struct cred`
From:   Alice Ryhl <aliceryhl@google.com>
To:     benno.lossin@proton.me
Cc:     a.hindborg@samsung.com, alex.gaynor@gmail.com,
        aliceryhl@google.com, arve@android.com, bjorn3_gh@protonmail.com,
        boqun.feng@gmail.com, brauner@kernel.org, cmllamas@google.com,
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Benno Lossin <benno.lossin@proton.me> writes:
> On 12/6/23 12:59, Alice Ryhl wrote:
> > +/// Wraps the kernel's `struct cred`.
> > +///
> > +/// # Invariants
> > +///
> > +/// Instances of this type are always ref-counted, that is, a call to `get_cred` ensures that the
> > +/// allocation remains valid at least until the matching call to `put_cred`.
> > +#[repr(transparent)]
> > +pub struct Credential(pub(crate) Opaque<bindings::cred>);
> 
> Why is the field `pub(crate)`?

Historical accident. It isn't needed anymore. I'll remove it.

> > +    unsafe fn dec_ref(obj: core::ptr::NonNull<Self>) {
> > +        // SAFETY: The safety requirements guarantee that the refcount is nonzero.
> 
> Can you also justify the `cast()`?

Will do.

Alice