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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 2/6] rust: page: Convert to Ownable
In-Reply-To: <20250202-rust-page-v1-2-e3170d7fe55e@asahilina.net> (Asahi
	Lina's message of "Sun, 02 Feb 2025 22:05:44 +0900")
References: <20250202-rust-page-v1-0-e3170d7fe55e@asahilina.net>
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	<20250202-rust-page-v1-2-e3170d7fe55e@asahilina.net>
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Date: Wed, 19 Feb 2025 09:46:45 +0100
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"Asahi Lina" <lina@asahilina.net> writes:

> This allows Page references to be returned as borrowed references,
> without necessarily owning the struct page.
>
> Signed-off-by: Asahi Lina <lina@asahilina.net>
> ---
>  rust/kernel/page.rs | 30 ++++++++++++++++--------------
>  1 file changed, 16 insertions(+), 14 deletions(-)
>
> diff --git a/rust/kernel/page.rs b/rust/kernel/page.rs
> index fdac6c375fe46e1ba589f1640afeae3e001e39ae..0b6cbe02522ab6e6e1810288a=
d23af4e4aa587d8 100644
> --- a/rust/kernel/page.rs
> +++ b/rust/kernel/page.rs
> @@ -7,6 +7,7 @@
>      bindings,
>      error::code::*,
>      error::Result,
> +    types::{Opaque, Ownable, Owned},
>      uaccess::UserSliceReader,
>  };
>  use core::ptr::{self, NonNull};
> @@ -30,13 +31,10 @@ pub const fn page_align(addr: usize) -> usize {
>      (addr + (PAGE_SIZE - 1)) & PAGE_MASK
>  }
>
> -/// A pointer to a page that owns the page allocation.
> -///
> -/// # Invariants
> -///
> -/// The pointer is valid, and has ownership over the page.
> +/// An object representing a memory page in the kernel (`struct page`).

Can you  link to the header file containing `struct page`?

.. memory page in the kernel ([`struct page`]).

[`struct page`]: srctree/include/linux/mm_types.h

Otherwise looks good =F0=9F=91=8D


Best regards,
Andreas Hindborg