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Date: Mon, 26 Feb 2024 09:44:02 +0000
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Message-ID: <20240226-module-as-ptr-v1-1-83bc89213113@google.com>
Subject: [PATCH] rust: add `Module::as_ptr`
From: Alice Ryhl <aliceryhl@google.com>
To: Miguel Ojeda <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, 
	Wedson Almeida Filho <wedsonaf@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>, 
	Andreas Hindborg <a.hindborg@samsung.com>
Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Alice Ryhl <aliceryhl@google.com>
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This allows you to get a raw pointer to THIS_MODULE for use in unsafe
code. The Rust Binder RFC uses it when defining fops for the binderfs
component [1].

This doesn't really need to go in now - it could go in together with
Rust Binder like how it is sent in the Rust Binder RFC. However, the
upcoming 1.77.0 release of the Rust compiler introduces a new warning,
and applying this patch now will silence that warning. That allows us to
avoid adding the #[allow(dead_code)] annotation seen in [2].

Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/ [1]
Link: https://lore.kernel.org/all/20240217002717.57507-1-ojeda@kernel.org/ [2]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
---
 rust/kernel/lib.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index be68d5e567b1..1952a0df0a15 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -92,6 +92,13 @@ impl ThisModule {
     pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule {
         ThisModule(ptr)
     }
+
+    /// Access the raw pointer for this module.
+    ///
+    /// It is up to the user to use it correctly.
+    pub const fn as_ptr(&self) -> *mut bindings::module {
+        self.0
+    }
 }
 
 #[cfg(not(any(testlib, test)))]

---
base-commit: e944171070b65521c0513c01c56174ec8fd7d249
change-id: 20240226-module-as-ptr-08300b88525b

Best regards,
-- 
Alice Ryhl <aliceryhl@google.com>