summaryrefslogtreecommitdiff
path: root/rust/kernel/sync/arc.rs
diff options
context:
space:
mode:
Diffstat (limited to 'rust/kernel/sync/arc.rs')
-rw-r--r--rust/kernel/sync/arc.rs16
1 files changed, 13 insertions, 3 deletions
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index b45769a29541..de36d55e81d8 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -18,7 +18,8 @@
use crate::{
bindings,
error::{self, Error},
- init::{InPlaceInit, Init, PinInit},
+ init::{self, InPlaceInit, Init, PinInit},
+ try_init,
types::{ForeignOwnable, Opaque},
};
use alloc::boxed::Box;
@@ -31,6 +32,7 @@ use core::{
pin::Pin,
ptr::NonNull,
};
+use macros::pin_data;
mod std_vendor;
@@ -125,6 +127,7 @@ pub struct Arc<T: ?Sized> {
_p: PhantomData<ArcInner<T>>,
}
+#[pin_data]
#[repr(C)]
struct ArcInner<T: ?Sized> {
refcount: Opaque<bindings::refcount_t>,
@@ -505,9 +508,16 @@ 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>>, AllocError> {
- Ok(UniqueArc::<MaybeUninit<T>> {
+ // INVARIANT: The refcount is initialised to a non-zero value.
+ let inner = Box::try_init::<AllocError>(try_init!(ArcInner {
+ // SAFETY: There are no safety requirements for this FFI call.
+ refcount: Opaque::new(unsafe { bindings::REFCOUNT_INIT(1) }),
+ data <- init::uninit::<T, AllocError>(),
+ }? AllocError))?;
+ Ok(UniqueArc {
// INVARIANT: The newly-created object has a ref-count of 1.
- inner: Arc::try_new(MaybeUninit::uninit())?,
+ // SAFETY: The pointer from the `Box` is valid.
+ inner: unsafe { Arc::from_inner(Box::leak(inner).into()) },
})
}
}