diff options
| -rw-r--r-- | rust/kernel/sync/arc.rs | 18 | ||||
| -rw-r--r-- | rust/kernel/types.rs | 20 |
2 files changed, 19 insertions, 19 deletions
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs index fe334394c328..e351c701c166 100644 --- a/rust/kernel/sync/arc.rs +++ b/rust/kernel/sync/arc.rs @@ -349,25 +349,25 @@ impl<T: 'static> ForeignOwnable for Arc<T> { ManuallyDrop::new(self).ptr.as_ptr().cast() } - unsafe fn borrow<'a>(ptr: *mut crate::ffi::c_void) -> ArcBorrow<'a, T> { + unsafe fn from_foreign(ptr: *mut crate::ffi::c_void) -> Self { // SAFETY: The safety requirements of this function ensure that `ptr` comes from a previous // call to `Self::into_foreign`. let inner = unsafe { NonNull::new_unchecked(ptr.cast::<ArcInner<T>>()) }; - // SAFETY: The safety requirements of `from_foreign` ensure that the object remains alive - // for the lifetime of the returned value. - unsafe { ArcBorrow::new(inner) } + // SAFETY: By the safety requirement of this function, we know that `ptr` came from + // a previous call to `Arc::into_foreign`, which guarantees that `ptr` is valid and + // holds a reference count increment that is transferrable to us. + unsafe { Self::from_inner(inner) } } - unsafe fn from_foreign(ptr: *mut crate::ffi::c_void) -> Self { + unsafe fn borrow<'a>(ptr: *mut crate::ffi::c_void) -> ArcBorrow<'a, T> { // SAFETY: The safety requirements of this function ensure that `ptr` comes from a previous // call to `Self::into_foreign`. let inner = unsafe { NonNull::new_unchecked(ptr.cast::<ArcInner<T>>()) }; - // SAFETY: By the safety requirement of this function, we know that `ptr` came from - // a previous call to `Arc::into_foreign`, which guarantees that `ptr` is valid and - // holds a reference count increment that is transferrable to us. - unsafe { Self::from_inner(inner) } + // SAFETY: The safety requirements of `from_foreign` ensure that the object remains alive + // for the lifetime of the returned value. + unsafe { ArcBorrow::new(inner) } } } diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs index f9b398ee31fd..af316e291908 100644 --- a/rust/kernel/types.rs +++ b/rust/kernel/types.rs @@ -31,14 +31,6 @@ pub trait ForeignOwnable: Sized { /// [`ForeignOwnable::try_from_foreign`] can result in undefined behavior. fn into_foreign(self) -> *mut crate::ffi::c_void; - /// Borrows a foreign-owned object. - /// - /// # Safety - /// - /// `ptr` must have been returned by a previous call to [`ForeignOwnable::into_foreign`] for - /// which a previous matching [`ForeignOwnable::from_foreign`] hasn't been called yet. - unsafe fn borrow<'a>(ptr: *mut crate::ffi::c_void) -> Self::Borrowed<'a>; - /// Converts a foreign-owned object back to a Rust-owned one. /// /// # Safety @@ -67,6 +59,14 @@ pub trait ForeignOwnable: Sized { unsafe { Some(Self::from_foreign(ptr)) } } } + + /// Borrows a foreign-owned object. + /// + /// # Safety + /// + /// `ptr` must have been returned by a previous call to [`ForeignOwnable::into_foreign`] for + /// which a previous matching [`ForeignOwnable::from_foreign`] hasn't been called yet. + unsafe fn borrow<'a>(ptr: *mut crate::ffi::c_void) -> Self::Borrowed<'a>; } impl ForeignOwnable for () { @@ -76,9 +76,9 @@ impl ForeignOwnable for () { core::ptr::NonNull::dangling().as_ptr() } - unsafe fn borrow<'a>(_: *mut crate::ffi::c_void) -> Self::Borrowed<'a> {} - unsafe fn from_foreign(_: *mut crate::ffi::c_void) -> Self {} + + unsafe fn borrow<'a>(_: *mut crate::ffi::c_void) -> Self::Borrowed<'a> {} } /// Runs a cleanup function/closure when dropped. |