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Date: Mon, 30 Jun 2025 19:29:57 +0200
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Subject: Re: [PATCH v8 4/6] rust: debugfs: Support arbitrary owned backing for
 File
To: Matthew Maurer <mmaurer@google.com>
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>,
 Andreas Hindborg <a.hindborg@kernel.org>, Alice Ryhl <aliceryhl@google.com>,
 Trevor Gross <tmgross@umich.edu>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
 "Rafael J. Wysocki" <rafael@kernel.org>,
 Sami Tolvanen <samitolvanen@google.com>, Timur Tabi <ttabi@nvidia.com>,
 Benno Lossin <lossin@kernel.org>, linux-kernel@vger.kernel.org,
 rust-for-linux@vger.kernel.org, Dirk Behme <dirk.behme@de.bosch.com>
References: <20250627-debugfs-rust-v8-0-c6526e413d40@google.com>
 <20250627-debugfs-rust-v8-4-c6526e413d40@google.com>
From: Danilo Krummrich <dakr@kernel.org>
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In-Reply-To: <20250627-debugfs-rust-v8-4-c6526e413d40@google.com>
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On 6/28/25 1:18 AM, Matthew Maurer wrote:
> +    fn create_file<D: ForeignOwnable>(&self, _name: &CStr, data: D) -> File
> +    where
> +        for<'a> D::Borrowed<'a>: Display,
> +    {
> +        File {
> +            _foreign: ForeignHolder::new(data),
> +        }
>       }

What's the motivation for the ForeignHolder abstraction? Why not just make it
File<D> and store data directly?