[PATCH v4 10/28] rust: treewide: switch to our kernel `Box` type

Danilo Krummrich
2024-08-05T15:21:09Z

Now that we got the kernel `Box` type in place, convert all existing
`Box` users to make use of it.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
rust/kernel/init.rs | 41 ++++++++++++++++---------------
rust/kernel/init/__internal.rs | 2 +-
rust/kernel/sync/arc.rs | 17 ++++++-------
rust/kernel/sync/condvar.rs | 4 +--
rust/kernel/sync/lock/mutex.rs | 2 +-
rust/kernel/sync/lock/spinlock.rs | 2 +-
rust/kernel/workqueue.rs | 20 +++++++--------
7 files changed, 44 insertions(+), 44 deletions(-)

diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index 5fd7a0ffabd2..b3159eb1eb02 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -68,7 +68,7 @@
//! # a <- new_mutex!(42, "Foo::a"),
//! # b: 24,
//! # });
-//! let foo: Result<Pin<Box<Foo>>> = Box::pin_init(foo, GFP_KERNEL);
+//! let foo: Result<Pin<KBox<Foo>>> = KBox::pin_init(foo, GFP_KERNEL);
//! ```
//!
//! For more information see the [`pin_init!`] macro.
@@ -93,14 +93,14 @@
//! struct DriverData {
//! #[pin]
//! status: Mutex<i32>,
-//! buffer: Box<[u8; 1_000_000]>,
+//! buffer: KBox<[u8; 1_000_000]>,
//! }
//!
//! impl DriverData {
//! fn new() -> impl PinInit<Self, Error> {
//! try_pin_init!(Self {
//! status <- new_mutex!(0, "DriverData::status"),
-//! buffer: Box::init(kernel::init::zeroed(), GFP_KERNEL)?,
+//! buffer: KBox::init(kernel::init::zeroed(), GFP_KERNEL)?,
//! })
//! }
//! }
@@ -211,7 +211,7 @@
//! [`pin_init!`]: crate::pin_init!

use crate::{
- alloc::{box_ext::BoxExt, AllocError, Allocator, Flags},
+ alloc::{box_ext::BoxExt, AllocError, Allocator, Flags, KBox},
error::{self, Error},
sync::UniqueArc,
types::{Opaque, ScopeGuard},
@@ -297,7 +297,7 @@ macro_rules! stack_pin_init {
/// struct Foo {
/// #[pin]
/// a: Mutex<usize>,
-/// b: Box<Bar>,
+/// b: KBox<Bar>,
/// }
///
/// struct Bar {
@@ -306,7 +306,7 @@ macro_rules! stack_pin_init {
///
/// stack_try_pin_init!(let foo: Result<Pin<&mut Foo>, AllocError> = pin_init!(Foo {
/// a <- new_mutex!(42),
-/// b: Box::new(Bar {
+/// b: KBox::new(Bar {
/// x: 64,
/// }, GFP_KERNEL)?,
/// }));
@@ -323,7 +323,7 @@ macro_rules! stack_pin_init {
/// struct Foo {
/// #[pin]
/// a: Mutex<usize>,
-/// b: Box<Bar>,
+/// b: KBox<Bar>,
/// }
///
/// struct Bar {
@@ -332,7 +332,7 @@ macro_rules! stack_pin_init {
///
/// stack_try_pin_init!(let foo: Pin<&mut Foo> =? pin_init!(Foo {
/// a <- new_mutex!(42),
-/// b: Box::new(Bar {
+/// b: KBox::new(Bar {
/// x: 64,
/// }, GFP_KERNEL)?,
/// }));
@@ -391,7 +391,7 @@ macro_rules! stack_try_pin_init {
/// },
/// });
/// # initializer }
-/// # Box::pin_init(demo(), GFP_KERNEL).unwrap();
+/// # KBox::pin_init(demo(), GFP_KERNEL).unwrap();
/// ```
///
/// Arbitrary Rust expressions can be used to set the value of a variable.
@@ -461,7 +461,7 @@ macro_rules! stack_try_pin_init {
/// # })
/// # }
/// # }
-/// let foo = Box::pin_init(Foo::new(), GFP_KERNEL);
+/// let foo = KBox::pin_init(Foo::new(), GFP_KERNEL);
/// ```
///
/// They can also easily embed it into their own `struct`s:
@@ -593,7 +593,7 @@ macro_rules! pin_init {
/// use kernel::{init::{self, PinInit}, error::Error};
/// #[pin_data]
/// struct BigBuf {
-/// big: Box<[u8; 1024 * 1024 * 1024]>,
+/// big: KBox<[u8; 1024 * 1024 * 1024]>,
/// small: [u8; 1024 * 1024],
/// ptr: *mut u8,
/// }
@@ -601,7 +601,7 @@ macro_rules! pin_init {
/// impl BigBuf {
/// fn new() -> impl PinInit<Self, Error> {
/// try_pin_init!(Self {
-/// big: Box::init(init::zeroed(), GFP_KERNEL)?,
+/// big: KBox::init(init::zeroed(), GFP_KERNEL)?,
/// small: [0; 1024 * 1024],
/// ptr: core::ptr::null_mut(),
/// }? Error)
@@ -693,16 +693,16 @@ macro_rules! init {
/// # Examples
///
/// ```rust
-/// use kernel::{init::{PinInit, zeroed}, error::Error};
+/// use kernel::{alloc::KBox, init::{PinInit, zeroed}, error::Error};
/// struct BigBuf {
-/// big: Box<[u8; 1024 * 1024 * 1024]>,
+/// big: KBox<[u8; 1024 * 1024 * 1024]>,
/// small: [u8; 1024 * 1024],
/// }
///
/// impl BigBuf {
/// fn new() -> impl Init<Self, Error> {
/// try_init!(Self {
-/// big: Box::init(zeroed(), GFP_KERNEL)?,
+/// big: KBox::init(zeroed(), GFP_KERNEL)?,
/// small: [0; 1024 * 1024],
/// }? Error)
/// }
@@ -825,7 +825,7 @@ fn pin_chain<F>(self, f: F) -> ChainPinInit<Self, F, T, E>
}

/// An initializer returned by [`PinInit::pin_chain`].
-pub struct ChainPinInit<I, F, T: ?Sized, E>(I, F, __internal::Invariant<(E, Box<T>)>);
+pub struct ChainPinInit<I, F, T: ?Sized, E>(I, F, __internal::Invariant<(E, KBox<T>)>);

// SAFETY: The `__pinned_init` function is implemented such that it
// - returns `Ok(())` on successful initialization,
@@ -924,7 +924,7 @@ fn chain<F>(self, f: F) -> ChainInit<Self, F, T, E>
}

/// An initializer returned by [`Init::chain`].
-pub struct ChainInit<I, F, T: ?Sized, E>(I, F, __internal::Invariant<(E, Box<T>)>);
+pub struct ChainInit<I, F, T: ?Sized, E>(I, F, __internal::Invariant<(E, KBox<T>)>);

// SAFETY: The `__init` function is implemented such that it
// - returns `Ok(())` on successful initialization,
@@ -1008,8 +1008,9 @@ pub fn uninit<T, E>() -> impl Init<MaybeUninit<T>, E> {
/// # Examples
///
/// ```rust
-/// use kernel::{error::Error, init::init_array_from_fn};
-/// let array: Box<[usize; 1_000]> = Box::init::<Error>(init_array_from_fn(|i| i), GFP_KERNEL).unwrap();
+/// use kernel::{alloc::KBox, error::Error, init::init_array_from_fn};
+/// let array: KBox<[usize; 1_000]> =
+/// KBox::init::<Error>(init_array_from_fn(|i| i), GFP_KERNEL).unwrap();
/// assert_eq!(array.len(), 1_000);
/// ```
pub fn init_array_from_fn<I, const N: usize, T, E>(
@@ -1349,7 +1350,7 @@ macro_rules! impl_zeroable {
//
// In this case we are allowed to use `T: ?Sized`, since all zeros is the `None` variant.
{<T: ?Sized>} Option<NonNull<T>>,
- {<T: ?Sized>} Option<Box<T>>,
+ {<T: ?Sized>} Option<KBox<T>>,

// SAFETY: `null` pointer is valid.
//
diff --git a/rust/kernel/init/__internal.rs b/rust/kernel/init/__internal.rs
index db3372619ecd..dfb2204918c7 100644
--- a/rust/kernel/init/__internal.rs
+++ b/rust/kernel/init/__internal.rs
@@ -102,7 +102,7 @@ fn make_closure<F, O, E>(self, f: F) -> F
}
}

-pub struct AllData<T: ?Sized>(PhantomData<fn(Box<T>) -> Box<T>>);
+pub struct AllData<T: ?Sized>(PhantomData<fn(KBox<T>) -> KBox<T>>);

impl<T: ?Sized> Clone for AllData<T> {
fn clone(&self) -> Self {
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index 3673496c2363..b5c84995d7d2 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -16,13 +16,12 @@
//! [`Arc`]: https://doc.rust-lang.org/std/sync/struct.Arc.html

use crate::{
- alloc::{box_ext::BoxExt, AllocError, Flags},
+ alloc::{AllocError, Flags, KBox},
error::{self, Error},
init::{self, InPlaceInit, Init, PinInit},
try_init,
types::{ForeignOwnable, Opaque},
};
-use alloc::boxed::Box;
use core::{
alloc::Layout,
fmt,
@@ -203,11 +202,11 @@ pub fn new(contents: T, flags: Flags) -> Result<Self, AllocError> {
data: contents,
};

- let inner = <Box<_> as BoxExt<_>>::new(value, flags)?;
+ let inner = KBox::new(value, flags)?;

// SAFETY: We just created `inner` with a reference count of 1, which is owned by the new
// `Arc` object.
- Ok(unsafe { Self::from_inner(Box::leak(inner).into()) })
+ Ok(unsafe { Self::from_inner(KBox::leak(inner).into()) })
}

/// Use the given initializer to in-place initialize a `T`.
@@ -422,8 +421,8 @@ fn drop(&mut self) {
if is_zero {
// The count reached zero, we must free the memory.
//
- // SAFETY: The pointer was initialised from the result of `Box::leak`.
- unsafe { drop(Box::from_raw(self.ptr.as_ptr())) };
+ // SAFETY: The pointer was initialised from the result of `KBox::leak`.
+ unsafe { drop(KBox::from_raw(self.ptr.as_ptr())) };
}
}
}
@@ -668,7 +667,7 @@ pub fn new(value: T, flags: Flags) -> Result<Self, AllocError> {
/// Tries to allocate a new [`UniqueArc`] instance whose contents are not initialised yet.
pub fn new_uninit(flags: Flags) -> Result<UniqueArc<MaybeUninit<T>>, AllocError> {
// INVARIANT: The refcount is initialised to a non-zero value.
- let inner = Box::try_init::<AllocError>(
+ let inner = KBox::try_init::<AllocError>(
try_init!(ArcInner {
// SAFETY: There are no safety requirements for this FFI call.
refcount: Opaque::new(unsafe { bindings::REFCOUNT_INIT(1) }),
@@ -678,8 +677,8 @@ pub fn new_uninit(flags: Flags) -> Result<UniqueArc<MaybeUninit<T>>, AllocError>
)?;
Ok(UniqueArc {
// INVARIANT: The newly-created object has a refcount of 1.
- // SAFETY: The pointer from the `Box` is valid.
- inner: unsafe { Arc::from_inner(Box::leak(inner).into()) },
+ // SAFETY: The pointer from the `KBox` is valid.
+ inner: unsafe { Arc::from_inner(KBox::leak(inner).into()) },
})
}
}
diff --git a/rust/kernel/sync/condvar.rs b/rust/kernel/sync/condvar.rs
index 2b306afbe56d..2081932bb4b9 100644
--- a/rust/kernel/sync/condvar.rs
+++ b/rust/kernel/sync/condvar.rs
@@ -70,8 +70,8 @@ macro_rules! new_condvar {
/// }
///
/// /// Allocates a new boxed `Example`.
-/// fn new_example() -> Result<Pin<Box<Example>>> {
-/// Box::pin_init(pin_init!(Example {
+/// fn new_example() -> Result<Pin<KBox<Example>>> {
+/// KBox::pin_init(pin_init!(Example {
/// value <- new_mutex!(0),
/// value_changed <- new_condvar!(),
/// }), GFP_KERNEL)
diff --git a/rust/kernel/sync/lock/mutex.rs b/rust/kernel/sync/lock/mutex.rs
index 30632070ee67..f8f6d530db7d 100644
--- a/rust/kernel/sync/lock/mutex.rs
+++ b/rust/kernel/sync/lock/mutex.rs
@@ -58,7 +58,7 @@ macro_rules! new_mutex {
/// }
///
/// // Allocate a boxed `Example`.
-/// let e = Box::pin_init(Example::new(), GFP_KERNEL)?;
+/// let e = KBox::pin_init(Example::new(), GFP_KERNEL)?;
/// assert_eq!(e.c, 10);
/// assert_eq!(e.d.lock().a, 20);
/// assert_eq!(e.d.lock().b, 30);
diff --git a/rust/kernel/sync/lock/spinlock.rs b/rust/kernel/sync/lock/spinlock.rs
index ea5c5bc1ce12..a9096a4dc42a 100644
--- a/rust/kernel/sync/lock/spinlock.rs
+++ b/rust/kernel/sync/lock/spinlock.rs
@@ -56,7 +56,7 @@ macro_rules! new_spinlock {
/// }
///
/// // Allocate a boxed `Example`.
-/// let e = Box::pin_init(Example::new(), GFP_KERNEL)?;
+/// let e = KBox::pin_init(Example::new(), GFP_KERNEL)?;
/// assert_eq!(e.c, 10);
/// assert_eq!(e.d.lock().a, 20);
/// assert_eq!(e.d.lock().b, 30);
diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index 553a5cba2adc..94318472507f 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -216,7 +216,7 @@ pub fn try_spawn<T: 'static + Send + FnOnce()>(
func: Some(func),
});

- self.enqueue(Box::pin_init(init, flags).map_err(|_| AllocError)?);
+ self.enqueue(KBox::pin_init(init, flags).map_err(|_| AllocError)?);
Ok(())
}
}
@@ -239,9 +239,9 @@ fn project(self: Pin<&mut Self>) -> &mut Option<T> {
}

impl<T: FnOnce()> WorkItem for ClosureWork<T> {
- type Pointer = Pin<Box<Self>>;
+ type Pointer = Pin<KBox<Self>>;

- fn run(mut this: Pin<Box<Self>>) {
+ fn run(mut this: Pin<KBox<Self>>) {
if let Some(func) = this.as_mut().project().take() {
(func)()
}
@@ -297,7 +297,7 @@ unsafe fn __enqueue<F>(self, queue_work_on: F) -> Self::EnqueueOutput

/// Defines the method that should be called directly when a work item is executed.
///
-/// This trait is implemented by `Pin<Box<T>>` and [`Arc<T>`], and is mainly intended to be
+/// This trait is implemented by `Pin<KBox<T>>` and [`Arc<T>`], and is mainly intended to be
/// implemented for smart pointer types. For your own structs, you would implement [`WorkItem`]
/// instead. The [`run`] method on this trait will usually just perform the appropriate
/// `container_of` translation and then call into the [`run`][WorkItem::run] method from the
@@ -329,7 +329,7 @@ pub unsafe trait WorkItemPointer<const ID: u64>: RawWorkItem<ID> {
/// This trait is used when the `work_struct` field is defined using the [`Work`] helper.
pub trait WorkItem<const ID: u64 = 0> {
/// The pointer type that this struct is wrapped in. This will typically be `Arc<Self>` or
- /// `Pin<Box<Self>>`.
+ /// `Pin<KBox<Self>>`.
type Pointer: WorkItemPointer<ID>;

/// The method that should be called when this work item is executed.
@@ -565,7 +565,7 @@ unsafe fn __enqueue<F>(self, queue_work_on: F) -> Self::EnqueueOutput
}
}

-unsafe impl<T, const ID: u64> WorkItemPointer<ID> for Pin<Box<T>>
+unsafe impl<T, const ID: u64> WorkItemPointer<ID> for Pin<KBox<T>>
where
T: WorkItem<ID, Pointer = Self>,
T: HasWork<T, ID>,
@@ -576,7 +576,7 @@ unsafe impl<T, const ID: u64> WorkItemPointer<ID> for Pin<Box<T>>
// SAFETY: This computes the pointer that `__enqueue` got from `Arc::into_raw`.
let ptr = unsafe { T::work_container_of(ptr) };
// SAFETY: This pointer comes from `Arc::into_raw` and we've been given back ownership.
- let boxed = unsafe { Box::from_raw(ptr) };
+ let boxed = unsafe { KBox::from_raw(ptr) };
// SAFETY: The box was already pinned when it was enqueued.
let pinned = unsafe { Pin::new_unchecked(boxed) };

@@ -584,7 +584,7 @@ unsafe impl<T, const ID: u64> WorkItemPointer<ID> for Pin<Box<T>>
}
}

-unsafe impl<T, const ID: u64> RawWorkItem<ID> for Pin<Box<T>>
+unsafe impl<T, const ID: u64> RawWorkItem<ID> for Pin<KBox<T>>
where
T: WorkItem<ID, Pointer = Self>,
T: HasWork<T, ID>,
@@ -598,9 +598,9 @@ unsafe fn __enqueue<F>(self, queue_work_on: F) -> Self::EnqueueOutput
// SAFETY: We're not going to move `self` or any of its fields, so its okay to temporarily
// remove the `Pin` wrapper.
let boxed = unsafe { Pin::into_inner_unchecked(self) };
- let ptr = Box::into_raw(boxed);
+ let ptr = KBox::into_raw(boxed);

- // SAFETY: Pointers into a `Box` point at a valid value.
+ // SAFETY: Pointers into a `KBox` point at a valid value.
let work_ptr = unsafe { T::raw_get_work(ptr) };
// SAFETY: `raw_get_work` returns a pointer to a valid value.
let work_ptr = unsafe { Work::raw_get(work_ptr) };
--
2.45.2