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Date:   Wed, 17 May 2023 20:08:14 +0000
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Subject: [PATCH v1 2/2] rust: sync: implement `AsRef<T>` for `Arc<T>`
From:   Alice Ryhl <aliceryhl@google.com>
To:     Miguel Ojeda <ojeda@kernel.org>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>
Cc:     Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        "=?UTF-8?q?Bj=C3=B6rn=20Roy=20Baron?=" <bjorn3_gh@protonmail.com>,
        Benno Lossin <benno.lossin@proton.me>,
        Will Deacon <will@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alice Ryhl <aliceryhl@google.com>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev,
        Wedson Almeida Filho <walmeida@microsoft.com>
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This trait lets you use `Arc<T>` in code that is generic over smart
pointer types.

The `AsRef` trait should be implemented on all smart pointers. The
standard library also implements it on the ordinary `Arc`.

Co-developed-by: Wedson Almeida Filho <walmeida@microsoft.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
---
 rust/kernel/sync/arc.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index 274febe3bb06..9ec911e4a0c7 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -264,6 +264,12 @@ impl<T: ?Sized> Deref for Arc<T> {
     }
 }
 
+impl<T: ?Sized> AsRef<T> for Arc<T> {
+    fn as_ref(&self) -> &T {
+        self.deref()
+    }
+}
+
 impl<T: ?Sized> Clone for Arc<T> {
     fn clone(&self) -> Self {
         // INVARIANT: C `refcount_inc` saturates the refcount, so it cannot overflow to zero.
-- 
2.40.1.606.ga4b1b128d6-goog