[PATCH 1/4] rust: revocable: support fallible PinInit types

From: Danilo Krummrich
Date: Thu Jun 12 2025 - 10:57:08 EST


Currently, Revocable::new() only supports infallible PinInit
implementations, i.e. impl PinInit<T, Infallible>.

This has been sufficient so far, since users such as Devres do not
support fallibility.

Since this is about to change, make Revocable::new() generic over the
error type E.

Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
---
rust/kernel/devres.rs | 2 +-
rust/kernel/revocable.rs | 7 +++++--
2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs
index d8bdf2bdb879..a7df9fbd724f 100644
--- a/rust/kernel/devres.rs
+++ b/rust/kernel/devres.rs
@@ -98,7 +98,7 @@ struct DevresInner<T> {
impl<T> DevresInner<T> {
fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> {
let inner = Arc::pin_init(
- pin_init!( DevresInner {
+ try_pin_init!( DevresInner {
dev: dev.into(),
callback: Self::devres_callback,
data <- Revocable::new(data),
diff --git a/rust/kernel/revocable.rs b/rust/kernel/revocable.rs
index fa1fd70efa27..41b8fe374af6 100644
--- a/rust/kernel/revocable.rs
+++ b/rust/kernel/revocable.rs
@@ -82,8 +82,11 @@ unsafe impl<T: Sync + Send> Sync for Revocable<T> {}

impl<T> Revocable<T> {
/// Creates a new revocable instance of the given data.
- pub fn new(data: impl PinInit<T>) -> impl PinInit<Self> {
- pin_init!(Self {
+ pub fn new<E>(data: impl PinInit<T, E>) -> impl PinInit<Self, Error>
+ where
+ Error: From<E>,
+ {
+ try_pin_init!(Self {
is_available: AtomicBool::new(true),
data <- Opaque::pin_init(data),
})
--
2.49.0