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diff --git a/rust/kernel/sync/atomic/ordering.rs b/rust/kernel/sync/atomic/ordering.rs
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+// SPDX-License-Identifier: GPL-2.0
+
+//! Memory orderings.
+//!
+//! The semantics of these orderings follows the [`LKMM`] definitions and rules.
+//!
+//! - [`Acquire`] provides ordering between the load part of the annotated operation and all the
+//!   following memory accesses, and if there is a store part, the store part has the [`Relaxed`]
+//!   ordering.
+//! - [`Release`] provides ordering between all the preceding memory accesses and the store part of
+//!   the annotated operation, and if there is a load part, the load part has the [`Relaxed`]
+//!   ordering.
+//! - [`Full`] means "fully-ordered", that is:
+//!   - It provides ordering between all the preceding memory accesses and the annotated operation.
+//!   - It provides ordering between the annotated operation and all the following memory accesses.
+//!   - It provides ordering between all the preceding memory accesses and all the following memory
+//!     accesses.
+//!   - All the orderings are the same strength as a full memory barrier (i.e. `smp_mb()`).
+//! - [`Relaxed`] provides no ordering except the dependency orderings. Dependency orderings are
+//!   described in "DEPENDENCY RELATIONS" in [`LKMM`]'s [`explanation`].
+//!
+//! [`LKMM`]: srctree/tools/memory-model/
+//! [`explanation`]: srctree/tools/memory-model/Documentation/explanation.txt
+
+/// The annotation type for relaxed memory ordering, for the description of relaxed memory
+/// ordering, see [module-level documentation].
+///
+/// [module-level documentation]: crate::sync::atomic::ordering
+pub struct Relaxed;
+
+/// The annotation type for acquire memory ordering, for the description of acquire memory
+/// ordering, see [module-level documentation].
+///
+/// [module-level documentation]: crate::sync::atomic::ordering
+pub struct Acquire;
+
+/// The annotation type for release memory ordering, for the description of release memory
+/// ordering, see [module-level documentation].
+///
+/// [module-level documentation]: crate::sync::atomic::ordering
+pub struct Release;
+
+/// The annotation type for fully-ordered memory ordering, for the description fully-ordered memory
+/// ordering, see [module-level documentation].
+///
+/// [module-level documentation]: crate::sync::atomic::ordering
+pub struct Full;
+
+/// Describes the exact memory ordering.
+#[doc(hidden)]
+pub enum OrderingType {
+    /// Relaxed ordering.
+    Relaxed,
+    /// Acquire ordering.
+    Acquire,
+    /// Release ordering.
+    Release,
+    /// Fully-ordered.
+    Full,
+}
+
+mod internal {
+    /// Sealed trait, can be only implemented inside atomic mod.
+    pub trait Sealed {}
+
+    impl Sealed for super::Relaxed {}
+    impl Sealed for super::Acquire {}
+    impl Sealed for super::Release {}
+    impl Sealed for super::Full {}
+}
+
+/// The trait bound for annotating operations that support any ordering.
+pub trait Ordering: internal::Sealed {
+    /// Describes the exact memory ordering.
+    const TYPE: OrderingType;
+}
+
+impl Ordering for Relaxed {
+    const TYPE: OrderingType = OrderingType::Relaxed;
+}
+
+impl Ordering for Acquire {
+    const TYPE: OrderingType = OrderingType::Acquire;
+}
+
+impl Ordering for Release {
+    const TYPE: OrderingType = OrderingType::Release;
+}
+
+impl Ordering for Full {
+    const TYPE: OrderingType = OrderingType::Full;
+}
+
+/// The trait bound for operations that only support acquire or relaxed ordering.
+pub trait AcquireOrRelaxed: Ordering {}
+
+impl AcquireOrRelaxed for Acquire {}
+impl AcquireOrRelaxed for Relaxed {}
+
+/// The trait bound for operations that only support release or relaxed ordering.
+pub trait ReleaseOrRelaxed: Ordering {}
+
+impl ReleaseOrRelaxed for Release {}
+impl ReleaseOrRelaxed for Relaxed {}