[PATCH v6 03/15] rust: sync: change error type of constructor functions

From: Benno Lossin
Date: Wed Apr 05 2023 - 15:36:03 EST


Change the error type of the constructors of `Arc` and `UniqueArc` to be
`AllocError` instead of `Error`. This makes the API more clear as to
what can go wrong when calling `try_new` or its variants.

Signed-off-by: Benno Lossin <y86-dev@xxxxxxxxxxxxxx>
Reviewed-by: Andreas Hindborg <a.hindborg@xxxxxxxxxxx>
Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Reviewed-by: Gary Guo <gary@xxxxxxxxxxx>
---
rust/kernel/sync/arc.rs | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index f2f1c83d72ba..aa7135f0f238 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -17,11 +17,11 @@

use crate::{
bindings,
- error::Result,
types::{ForeignOwnable, Opaque},
};
use alloc::boxed::Box;
use core::{
+ alloc::AllocError,
marker::{PhantomData, Unsize},
mem::{ManuallyDrop, MaybeUninit},
ops::{Deref, DerefMut},
@@ -149,7 +149,7 @@ unsafe impl<T: ?Sized + Sync + Send> Sync for Arc<T> {}

impl<T> Arc<T> {
/// Constructs a new reference counted instance of `T`.
- pub fn try_new(contents: T) -> Result<Self> {
+ pub fn try_new(contents: T) -> Result<Self, AllocError> {
// INVARIANT: The refcount is initialised to a non-zero value.
let value = ArcInner {
// SAFETY: There are no safety requirements for this FFI call.
@@ -469,7 +469,7 @@ pub struct UniqueArc<T: ?Sized> {

impl<T> UniqueArc<T> {
/// Tries to allocate a new [`UniqueArc`] instance.
- pub fn try_new(value: T) -> Result<Self> {
+ pub fn try_new(value: T) -> Result<Self, AllocError> {
Ok(Self {
// INVARIANT: The newly-created object has a ref-count of 1.
inner: Arc::try_new(value)?,
@@ -477,7 +477,7 @@ impl<T> UniqueArc<T> {
}

/// Tries to allocate a new [`UniqueArc`] instance whose contents are not initialised yet.
- pub fn try_new_uninit() -> Result<UniqueArc<MaybeUninit<T>>> {
+ pub fn try_new_uninit() -> Result<UniqueArc<MaybeUninit<T>>, AllocError> {
Ok(UniqueArc::<MaybeUninit<T>> {
// INVARIANT: The newly-created object has a ref-count of 1.
inner: Arc::try_new(MaybeUninit::uninit())?,
--
2.39.2