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From: Andreas Hindborg <a.hindborg@kernel.org>
To: "Asahi Lina" <lina@asahilina.net>
Cc: "Miguel Ojeda" <ojeda@kernel.org>,  "Alex Gaynor"
 <alex.gaynor@gmail.com>,  "Boqun Feng" <boqun.feng@gmail.com>,  "Gary Guo"
 <gary@garyguo.net>,  =?utf-8?Q?Bj=C3=B6rn?= Roy Baron
 <bjorn3_gh@protonmail.com>,  "Benno
 Lossin" <benno.lossin@proton.me>,  "Alice Ryhl" <aliceryhl@google.com>,
  "Trevor Gross" <tmgross@umich.edu>,  "Jann Horn" <jannh@google.com>,
  "Matthew Wilcox" <willy@infradead.org>,  "Paolo Bonzini"
 <pbonzini@redhat.com>,  "Danilo Krummrich" <dakr@kernel.org>,  "Wedson
 Almeida Filho" <wedsonaf@gmail.com>,  "Valentin Obst"
 <kernel@valentinobst.de>,  "Andrew Morton" <akpm@linux-foundation.org>,
  <linux-mm@kvack.org>,  <airlied@redhat.com>,  "Abdiel Janulgue"
 <abdiel.janulgue@gmail.com>,  <rust-for-linux@vger.kernel.org>,
  <linux-kernel@vger.kernel.org>,  <asahi@lists.linux.dev>
Subject: Re: [PATCH 1/6] rust: types: Add Ownable/Owned types
In-Reply-To: <20250202-rust-page-v1-1-e3170d7fe55e@asahilina.net> (Asahi
	Lina's message of "Sun, 02 Feb 2025 22:05:43 +0900")
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	<20250202-rust-page-v1-1-e3170d7fe55e@asahilina.net>
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Date: Wed, 19 Feb 2025 09:37:50 +0100
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"Asahi Lina" <lina@asahilina.net> writes:

> By analogy to AlwaysRefCounted and ARef, an Ownable type is a (typically
> C FFI) type that *may* be owned by Rust, but need not be. Unlike
> AlwaysRefCounted, this mechanism expects the reference to be unique
> within Rust, and does not allow cloning.
>
> Conceptually, this is similar to a KBox<T>, except that it delegates
> resource management to the T instead of using a generic allocator.
>
> Signed-off-by: Asahi Lina <lina@asahilina.net>

Over all looks good to me - I agree with the points already discussed.

Could you put it in a separate module and file? `kernel::types::ownable`
and then `pub use` in `types.rs`. `types.rs` is getting quite busy.


Best regards,
Andreas Hindborg