Replace the call to `xa_load` with `xas_load` in `Guard::load`. The
`xa_load` function takes the RCU lock internally, which we do not need,
since the `Guard` already holds an exclusive lock on the `XArray`. The
`xas_load` function operates on `xa_state` and assumes the required locks
are already held.
This change also removes the `#[expect(dead_code)]` annotation from
`XArrayState` and its constructor, as they are now in use.
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
rust/kernel/xarray.rs | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/rust/kernel/xarray.rs b/rust/kernel/xarray.rs
index d1246ec114898..eadddafb180ec 100644
--- a/rust/kernel/xarray.rs
+++ b/rust/kernel/xarray.rs
@@ -215,10 +215,8 @@ fn load<F, U>(&self, index: usize, f: F) -> Option<U>
where
F: FnOnce(NonNull<c_void>) -> U,
{
- // SAFETY: `self.xa.xa` is always valid by the type invariant.
- let ptr = unsafe { bindings::xa_load(self.xa.xa.get(), index) };
- let ptr = NonNull::new(ptr.cast())?;
- Some(f(ptr))
+ let mut state = XArrayState::new(self, index);
+ Some(f(state.load()?))
}
/// Checks if the XArray contains an element at the specified index.
@@ -327,7 +325,6 @@ pub fn store(
/// # Invariants
///
/// - `state` is always a valid `bindings::xa_state`.
-#[expect(dead_code)]
pub(crate) struct XArrayState<'a, 'b, T: ForeignOwnable> {
/// Holds a reference to the lock guard to ensure the lock is not dropped
/// while `Self` is live.
@@ -336,7 +333,6 @@ pub(crate) struct XArrayState<'a, 'b, T: ForeignOwnable> {
}
impl<'a, 'b, T: ForeignOwnable> XArrayState<'a, 'b, T> {
- #[expect(dead_code)]
fn new(access: &'b Guard<'a, T>, index: usize) -> Self {
let ptr = access.xa.xa.get();
// INVARIANT: We initialize `self.state` to a valid value below.
@@ -356,6 +352,13 @@ fn new(access: &'b Guard<'a, T>, index: usize) -> Self {
},
}
}
+
+ fn load(&mut self) -> Option<NonNull<c_void>> {
+ // SAFETY: `state.state` is always valid by the type invariant of
+ // `XArrayState and we hold the xarray lock`.
+ let ptr = unsafe { bindings::xas_load(&raw mut self.state) };
+ NonNull::new(ptr.cast())
+ }
}
// SAFETY: `XArray<T>` has no shared mutable state so it is `Send` iff `T` is `Send`.
--
2.51.2