Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
new file mode 100644
index 0000000000..d219ee518e
--- /dev/null
+++ b/rust/kernel/sync.rs
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Synchronisation primitives.
+//!
+//! This module contains the kernel APIs related to synchronisation that have been ported or
+//! wrapped for usage by Rust code in the kernel.
+
+use crate::types::Opaque;
+
+mod arc;
+mod condvar;
+pub mod lock;
+mod locked_by;
+
+pub use arc::{Arc, ArcBorrow, UniqueArc};
+pub use condvar::CondVar;
+pub use lock::{mutex::Mutex, spinlock::SpinLock};
+pub use locked_by::LockedBy;
+
+/// Represents a lockdep class. It's a wrapper around C's `lock_class_key`.
+#[repr(transparent)]
+pub struct LockClassKey(Opaque<bindings::lock_class_key>);
+
+// SAFETY: `bindings::lock_class_key` is designed to be used concurrently from multiple threads and
+// provides its own synchronization.
+unsafe impl Sync for LockClassKey {}
+
+impl LockClassKey {
+    /// Creates a new lock class key.
+    pub const fn new() -> Self {
+        Self(Opaque::uninit())
+    }
+
+    pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key {
+        self.0.get()
+    }
+}
+
+/// Defines a new static lock class and returns a pointer to it.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! static_lock_class {
+    () => {{
+        static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new();
+        &CLASS
+    }};
+}
+
+/// Returns the given string, if one is provided, otherwise generates one based on the source code
+/// location.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! optional_name {
+    () => {
+        $crate::c_str!(::core::concat!(::core::file!(), ":", ::core::line!()))
+    };
+    ($name:literal) => {
+        $crate::c_str!($name)
+    };
+}