From: Boqun Feng <boqun.feng@xxxxxxxxx>
commit be2ca1e03965ffb214b6cbda0ffd84daeeb5f214 upstream.
To support a potential usage:
static foo: Opaque<Foo> = ..; // Or defined in an extern block.
...
fn bar() {
let ptr = foo.get();
}
`Opaque::get` need to be `const`, otherwise compiler will complain
because calls on statics are limited to const functions.
Also `Opaque::get` should be naturally `const` since it's a composition
of two `const` functions: `UnsafeCell::get` and `ptr::cast`.
Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Reviewed-by: Wedson Almeida Filho <walmeida@xxxxxxxxxxxxx>
Reviewed-by: Benno Lossin <benno.lossin@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240401214543.1242286-1-boqun.feng@xxxxxxxxx
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
rust/kernel/types.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/rust/kernel/types.rs
+++ b/rust/kernel/types.rs
@@ -248,7 +248,7 @@ impl<T> Opaque<T> {
}
/// Returns a raw pointer to the opaque data.
- pub fn get(&self) -> *mut T {
+ pub const fn get(&self) -> *mut T {
UnsafeCell::get(&self.value).cast::<T>()
}
Patches currently in stable-queue which might be from boqun.feng@xxxxxxxxx are
queue-6.6/rust-types-make-opaque-get-const.patch
queue-6.6/rust-macros-provide-correct-provenance-when-constructing-this_module.patch
