Messages in this thread Patch in this message | | | Date | Fri, 31 Mar 2023 21:54:52 +0000 | From | y86-dev@protonma ... | Subject | [PATCH v4 15/15] rust: sync: add functions for initializing `UniqueArc<MaybeUninit<T>>` |
| |
From: Benno Lossin <y86-dev@protonmail.com>
Add two functions `init_with` and `pin_init_with` to `UniqueArc<MaybeUninit<T>>` to initialize the memory of already allocated `UniqueArc`s. This is useful when you want to allocate memory check some condition inside of a context where allocation is forbidden and then conditionally initialize an object.
Signed-off-by: Benno Lossin <y86-dev@protonmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> --- rust/kernel/sync/arc.rs | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs index 5f64affd8f33..fddb7a2b1890 100644 --- a/rust/kernel/sync/arc.rs +++ b/rust/kernel/sync/arc.rs @@ -540,6 +540,30 @@ impl<T> UniqueArc<MaybeUninit<T>> { inner: unsafe { Arc::from_inner(inner.cast()) }, } } + + /// Initialize `self` using the given initializer. + pub fn init_with<E>(mut self, init: impl Init<T, E>) -> core::result::Result<UniqueArc<T>, E> { + // SAFETY: The supplied pointer is valid for initialization. + match unsafe { init.__init(self.as_mut_ptr()) } { + // SAFETY: Initialization completed successfully. + Ok(()) => Ok(unsafe { self.assume_init() }), + Err(err) => Err(err), + } + } + + /// Pin-initialize `self` using the given pin-initializer. + pub fn pin_init_with<E>( + mut self, + init: impl PinInit<T, E>, + ) -> core::result::Result<Pin<UniqueArc<T>>, E> { + // SAFETY: The supplied pointer is valid for initialization and we will later pin the value + // to ensure it does not move. + match unsafe { init.__pinned_init(self.as_mut_ptr()) } { + // SAFETY: Initialization completed successfully. + Ok(()) => Ok(unsafe { self.assume_init() }.into()), + Err(err) => Err(err), + } + } }
impl<T: ?Sized> From<UniqueArc<T>> for Pin<UniqueArc<T>> { -- 2.39.2
| |