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diff --git a/rust/kernel/sync/guard.rs b/rust/kernel/sync/guard.rs
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+// SPDX-License-Identifier: GPL-2.0
+
+//! A generic lock guard and trait.
+//!
+//! This module contains a lock guard that can be used with any locking primitive that implements
+//! the ([`Lock`]) trait. It also contains the definition of the trait, which can be leveraged by
+//! other constructs to work on generic locking primitives.
+
+use super::NeedsLockClass;
+use crate::{bindings, str::CStr, Bool, False, True};
+use core::pin::Pin;
+
+/// Allows mutual exclusion primitives that implement the [`Lock`] trait to automatically unlock
+/// when a guard goes out of scope. It also provides a safe and convenient way to access the data
+/// protected by the lock.
+#[must_use = "the lock unlocks immediately when the guard is unused"]
+pub struct Guard<'a, L: Lock<I> + ?Sized, I: LockInfo = WriteLock> {
+    pub(crate) lock: &'a L,
+    pub(crate) context: L::GuardContext,
+}
+
+// SAFETY: `Guard` is sync when the data protected by the lock is also sync. This is more
+// conservative than the default compiler implementation; more details can be found on
+// https://github.com/rust-lang/rust/issues/41622 -- it refers to `MutexGuard` from the standard
+// library.
+unsafe impl<L, I> Sync for Guard<'_, L, I>
+where
+    L: Lock<I> + ?Sized,
+    L::Inner: Sync,
+    I: LockInfo,
+{
+}
+
+impl<L: Lock<I> + ?Sized, I: LockInfo> core::ops::Deref for Guard<'_, L, I> {
+    type Target = L::Inner;
+
+    fn deref(&self) -> &Self::Target {
+        // SAFETY: The caller owns the lock, so it is safe to deref the protected data.
+        unsafe { &*self.lock.locked_data().get() }
+    }
+}
+
+impl<L: Lock<I> + ?Sized, I: LockInfo<Writable = True>> core::ops::DerefMut for Guard<'_, L, I> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        // SAFETY: The caller owns the lock, so it is safe to deref the protected data.
+        unsafe { &mut *self.lock.locked_data().get() }
+    }
+}
+
+impl<L: Lock<I> + ?Sized, I: LockInfo> Drop for Guard<'_, L, I> {
+    fn drop(&mut self) {
+        // SAFETY: The caller owns the lock, so it is safe to unlock it.
+        unsafe { self.lock.unlock(&mut self.context) };
+    }
+}
+
+impl<'a, L: Lock<I> + ?Sized, I: LockInfo> Guard<'a, L, I> {
+    /// Constructs a new immutable lock guard.
+    ///
+    /// # Safety
+    ///
+    /// The caller must ensure that it owns the lock.
+    pub(crate) unsafe fn new(lock: &'a L, context: L::GuardContext) -> Self {
+        Self { lock, context }
+    }
+}
+
+/// Specifies properties of a lock.
+pub trait LockInfo {
+    /// Determines if the data protected by a lock is writable.
+    type Writable: Bool;
+}
+
+/// A marker for locks that only allow reading.
+pub struct ReadLock;
+impl LockInfo for ReadLock {
+    type Writable = False;
+}
+
+/// A marker for locks that allow reading and writing.
+pub struct WriteLock;
+impl LockInfo for WriteLock {
+    type Writable = True;
+}
+
+/// A generic mutual exclusion primitive.
+///
+/// [`Guard`] is written such that any mutual exclusion primitive that can implement this trait can
+/// also benefit from having an automatic way to unlock itself.
+///
+/// # Safety
+///
+/// - Implementers of this trait with the [`WriteLock`] marker must ensure that only one thread/CPU
+///   may access the protected data once the lock is held, that is, between calls to `lock_noguard`
+///   and `unlock`.
+/// - Implementers of all other markers must ensure that a mutable reference to the protected data
+///   is not active in any thread/CPU because at least one shared reference is active between calls
+///   to `lock_noguard` and `unlock`.
+pub unsafe trait Lock<I: LockInfo = WriteLock> {
+    /// The type of the data protected by the lock.
+    type Inner: ?Sized;
+
+    /// The type of context, if any, that needs to be stored in the guard.
+    type GuardContext;
+
+    /// Acquires the lock, making the caller its owner.
+    #[must_use]
+    fn lock_noguard(&self) -> Self::GuardContext;
+
+    /// Reacquires the lock, making the caller its owner.
+    ///
+    /// The guard context before the last unlock is passed in.
+    ///
+    /// Locks that don't require this state on relock can simply use the default implementation
+    /// that calls [`Lock::lock_noguard`].
+    fn relock(&self, ctx: &mut Self::GuardContext) {
+        *ctx = self.lock_noguard();
+    }
+
+    /// Releases the lock, giving up ownership of the lock.
+    ///
+    /// # Safety
+    ///
+    /// It must only be called by the current owner of the lock.
+    unsafe fn unlock(&self, context: &mut Self::GuardContext);
+
+    /// Returns the data protected by the lock.
+    fn locked_data(&self) -> &core::cell::UnsafeCell<Self::Inner>;
+}
+
+/// A creator of instances of a mutual exclusion (lock) primitive.
+pub trait LockFactory {
+    /// The parametrised type of the mutual exclusion primitive that can be created by this factory.
+    type LockedType<T>;
+
+    /// Constructs a new instance of the mutual exclusion primitive.
+    ///
+    /// # Safety
+    ///
+    /// The caller must call [`LockIniter::init_lock`] before using the lock.
+    unsafe fn new_lock<T>(data: T) -> Self::LockedType<T>;
+}
+
+/// A lock that can be initialised with a single lock class key.
+pub trait LockIniter {
+    /// Initialises the lock instance so that it can be safely used.
+    ///
+    /// # Safety
+    ///
+    /// `key` must point to a valid memory location that will remain valid until the lock is
+    /// dropped.
+    unsafe fn init_lock(
+        self: Pin<&mut Self>,
+        name: &'static CStr,
+        key: *mut bindings::lock_class_key,
+    );
+}
+
+impl<L: LockIniter> NeedsLockClass for L {
+    unsafe fn init(
+        self: Pin<&mut Self>,
+        name: &'static CStr,
+        key: *mut bindings::lock_class_key,
+        _: *mut bindings::lock_class_key,
+    ) {
+        // SAFETY: The safety requirements of this function satisfy those of `init_lock`.
+        unsafe { self.init_lock(name, key) };
+    }
+}