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-rw-r--r--rust/kernel/sync/arc.rs78
-rw-r--r--rust/kernel/sync/completion.rs112
-rw-r--r--rust/kernel/sync/poll.rs2
3 files changed, 190 insertions, 2 deletions
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index c7af0aa48a0a..499175f637a7 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -25,6 +25,7 @@ use crate::{
};
use core::{
alloc::Layout,
+ borrow::{Borrow, BorrowMut},
fmt,
marker::PhantomData,
mem::{ManuallyDrop, MaybeUninit},
@@ -406,7 +407,7 @@ unsafe impl<T: 'static> ForeignOwnable for Arc<T> {
unsafe fn borrow_mut<'a>(ptr: *mut Self::PointedTo) -> ArcBorrow<'a, T> {
// SAFETY: The safety requirements for `borrow_mut` are a superset of the safety
// requirements for `borrow`.
- unsafe { Self::borrow(ptr) }
+ unsafe { <Self as ForeignOwnable>::borrow(ptr) }
}
}
@@ -426,6 +427,31 @@ impl<T: ?Sized> AsRef<T> for Arc<T> {
}
}
+/// # Examples
+///
+/// ```
+/// # use core::borrow::Borrow;
+/// # use kernel::sync::Arc;
+/// struct Foo<B: Borrow<u32>>(B);
+///
+/// // Owned instance.
+/// let owned = Foo(1);
+///
+/// // Shared instance.
+/// let arc = Arc::new(1, GFP_KERNEL)?;
+/// let shared = Foo(arc.clone());
+///
+/// let i = 1;
+/// // Borrowed from `i`.
+/// let borrowed = Foo(&i);
+/// # Ok::<(), Error>(())
+/// ```
+impl<T: ?Sized> Borrow<T> for Arc<T> {
+ fn borrow(&self) -> &T {
+ self.deref()
+ }
+}
+
impl<T: ?Sized> Clone for Arc<T> {
fn clone(&self) -> Self {
// SAFETY: By the type invariant, there is necessarily a reference to the object, so it is
@@ -834,6 +860,56 @@ impl<T: ?Sized> DerefMut for UniqueArc<T> {
}
}
+/// # Examples
+///
+/// ```
+/// # use core::borrow::Borrow;
+/// # use kernel::sync::UniqueArc;
+/// struct Foo<B: Borrow<u32>>(B);
+///
+/// // Owned instance.
+/// let owned = Foo(1);
+///
+/// // Owned instance using `UniqueArc`.
+/// let arc = UniqueArc::new(1, GFP_KERNEL)?;
+/// let shared = Foo(arc);
+///
+/// let i = 1;
+/// // Borrowed from `i`.
+/// let borrowed = Foo(&i);
+/// # Ok::<(), Error>(())
+/// ```
+impl<T: ?Sized> Borrow<T> for UniqueArc<T> {
+ fn borrow(&self) -> &T {
+ self.deref()
+ }
+}
+
+/// # Examples
+///
+/// ```
+/// # use core::borrow::BorrowMut;
+/// # use kernel::sync::UniqueArc;
+/// struct Foo<B: BorrowMut<u32>>(B);
+///
+/// // Owned instance.
+/// let owned = Foo(1);
+///
+/// // Owned instance using `UniqueArc`.
+/// let arc = UniqueArc::new(1, GFP_KERNEL)?;
+/// let shared = Foo(arc);
+///
+/// let mut i = 1;
+/// // Borrowed from `i`.
+/// let borrowed = Foo(&mut i);
+/// # Ok::<(), Error>(())
+/// ```
+impl<T: ?Sized> BorrowMut<T> for UniqueArc<T> {
+ fn borrow_mut(&mut self) -> &mut T {
+ self.deref_mut()
+ }
+}
+
impl<T: fmt::Display + ?Sized> fmt::Display for UniqueArc<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(self.deref(), f)
diff --git a/rust/kernel/sync/completion.rs b/rust/kernel/sync/completion.rs
new file mode 100644
index 000000000000..c50012a940a3
--- /dev/null
+++ b/rust/kernel/sync/completion.rs
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Completion support.
+//!
+//! Reference: <https://docs.kernel.org/scheduler/completion.html>
+//!
+//! C header: [`include/linux/completion.h`](srctree/include/linux/completion.h)
+
+use crate::{bindings, prelude::*, types::Opaque};
+
+/// Synchronization primitive to signal when a certain task has been completed.
+///
+/// The [`Completion`] synchronization primitive signals when a certain task has been completed by
+/// waking up other tasks that have been queued up to wait for the [`Completion`] to be completed.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::sync::{Arc, Completion};
+/// use kernel::workqueue::{self, impl_has_work, new_work, Work, WorkItem};
+///
+/// #[pin_data]
+/// struct MyTask {
+/// #[pin]
+/// work: Work<MyTask>,
+/// #[pin]
+/// done: Completion,
+/// }
+///
+/// impl_has_work! {
+/// impl HasWork<Self> for MyTask { self.work }
+/// }
+///
+/// impl MyTask {
+/// fn new() -> Result<Arc<Self>> {
+/// let this = Arc::pin_init(pin_init!(MyTask {
+/// work <- new_work!("MyTask::work"),
+/// done <- Completion::new(),
+/// }), GFP_KERNEL)?;
+///
+/// let _ = workqueue::system().enqueue(this.clone());
+///
+/// Ok(this)
+/// }
+///
+/// fn wait_for_completion(&self) {
+/// self.done.wait_for_completion();
+///
+/// pr_info!("Completion: task complete\n");
+/// }
+/// }
+///
+/// impl WorkItem for MyTask {
+/// type Pointer = Arc<MyTask>;
+///
+/// fn run(this: Arc<MyTask>) {
+/// // process this task
+/// this.done.complete_all();
+/// }
+/// }
+///
+/// let task = MyTask::new()?;
+/// task.wait_for_completion();
+/// # Ok::<(), Error>(())
+/// ```
+#[pin_data]
+pub struct Completion {
+ #[pin]
+ inner: Opaque<bindings::completion>,
+}
+
+// SAFETY: `Completion` is safe to be send to any task.
+unsafe impl Send for Completion {}
+
+// SAFETY: `Completion` is safe to be accessed concurrently.
+unsafe impl Sync for Completion {}
+
+impl Completion {
+ /// Create an initializer for a new [`Completion`].
+ pub fn new() -> impl PinInit<Self> {
+ pin_init!(Self {
+ inner <- Opaque::ffi_init(|slot: *mut bindings::completion| {
+ // SAFETY: `slot` is a valid pointer to an uninitialized `struct completion`.
+ unsafe { bindings::init_completion(slot) };
+ }),
+ })
+ }
+
+ fn as_raw(&self) -> *mut bindings::completion {
+ self.inner.get()
+ }
+
+ /// Signal all tasks waiting on this completion.
+ ///
+ /// This method wakes up all tasks waiting on this completion; after this operation the
+ /// completion is permanently done, i.e. signals all current and future waiters.
+ pub fn complete_all(&self) {
+ // SAFETY: `self.as_raw()` is a pointer to a valid `struct completion`.
+ unsafe { bindings::complete_all(self.as_raw()) };
+ }
+
+ /// Wait for completion of a task.
+ ///
+ /// This method waits for the completion of a task; it is not interruptible and there is no
+ /// timeout.
+ ///
+ /// See also [`Completion::complete_all`].
+ pub fn wait_for_completion(&self) {
+ // SAFETY: `self.as_raw()` is a pointer to a valid `struct completion`.
+ unsafe { bindings::wait_for_completion(self.as_raw()) };
+ }
+}
diff --git a/rust/kernel/sync/poll.rs b/rust/kernel/sync/poll.rs
index d7e6e59e124b..339ab6097be7 100644
--- a/rust/kernel/sync/poll.rs
+++ b/rust/kernel/sync/poll.rs
@@ -73,7 +73,7 @@ impl PollTable {
// be destroyed, the destructor must run. That destructor first removes all waiters,
// and then waits for an rcu grace period. Therefore, `cv.wait_queue_head` is valid for
// long enough.
- unsafe { qproc(file.as_ptr() as _, cv.wait_queue_head.get(), self.0.get()) };
+ unsafe { qproc(file.as_ptr().cast(), cv.wait_queue_head.get(), self.0.get()) };
}
}
}
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-06 05:39:04 +0000