Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Sat, 08 Apr 2023 12:25:29 +0000
To:     Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?utf-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        Alice Ryhl <alice@ryhl.io>, Andreas Hindborg <nmi@metaspace.dk>
From:   Benno Lossin <y86-dev@protonmail.com>
Cc:     rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev, Benno Lossin <y86-dev@protonmail.com>,
        Andreas Hindborg <a.hindborg@samsung.com>,
        Alice Ryhl <aliceryhl@google.com>
Subject: [PATCH v7 03/15] rust: sync: change error type of constructor functions
Message-ID: <20230408122429.1103522-4-y86-dev@protonmail.com>
In-Reply-To: <20230408122429.1103522-1-y86-dev@protonmail.com>
References: <20230408122429.1103522-1-y86-dev@protonmail.com>
Feedback-ID: 40624463:user:proton
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

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@protonmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
---
 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 =3D 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>>, AllocErro=
r> {
         Ok(UniqueArc::<MaybeUninit<T>> {
             // INVARIANT: The newly-created object has a ref-count of 1.
             inner: Arc::try_new(MaybeUninit::uninit())?,
--
2.39.2