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Signed-off-by: Tamir Duberstein Reviewed-by: Alice Ryhl Reviewed-by: Andreas Hindborg --- rust/kernel/alloc/kbox.rs | 22 ++++++++++------------ rust/kernel/sync/arc.rs | 12 ++++++------ rust/kernel/types.rs | 14 +++++++------- 3 files changed, 23 insertions(+), 25 deletions(-) diff --git a/rust/kernel/alloc/kbox.rs b/rust/kernel/alloc/kbox.rs index 7a5fdf7b660fb91ca2a8e5023d69d629b0d66062..de7fadeb7fdf5cf6742c2e9749e= 959ac5f82359e 100644 --- a/rust/kernel/alloc/kbox.rs +++ b/rust/kernel/alloc/kbox.rs @@ -355,18 +355,18 @@ impl ForeignOwnable for Box { type Borrowed<'a> =3D &'a T; =20 - fn into_foreign(self) -> *const core::ffi::c_void { - Box::into_raw(self).cast_const().cast() + fn into_foreign(self) -> *mut core::ffi::c_void { + Box::into_raw(self).cast() } =20 - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { - let ptr =3D ptr.cast_mut().cast(); + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self { + let ptr =3D ptr.cast(); // SAFETY: The safety requirements of this function ensure that `p= tr` comes from a previous // call to `Self::into_foreign`. unsafe { Box::from_raw(ptr) } } =20 - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> &'a T { + unsafe fn borrow<'a>(ptr: *mut core::ffi::c_void) -> &'a T { let ptr =3D ptr.cast(); // SAFETY: The safety requirements of this method ensure that the = object remains alive and // immutable for the duration of 'a. @@ -380,21 +380,19 @@ impl ForeignOwnable for Pin> { type Borrowed<'a> =3D Pin<&'a T>; =20 - fn into_foreign(self) -> *const core::ffi::c_void { + fn into_foreign(self) -> *mut core::ffi::c_void { // SAFETY: We are still treating the box as pinned. - Box::into_raw(unsafe { Pin::into_inner_unchecked(self) }) - .cast_const() - .cast() + Box::into_raw(unsafe { Pin::into_inner_unchecked(self) }).cast() } =20 - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { - let ptr =3D ptr.cast_mut().cast(); + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self { + let ptr =3D ptr.cast(); // SAFETY: The safety requirements of this function ensure that `p= tr` comes from a previous // call to `Self::into_foreign`. unsafe { Pin::new_unchecked(Box::from_raw(ptr)) } } =20 - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> Pin<&'a T> { + unsafe fn borrow<'a>(ptr: *mut core::ffi::c_void) -> Pin<&'a T> { let ptr =3D ptr.cast(); // SAFETY: The safety requirements for this function ensure that t= he object is still alive, // so it is safe to dereference the raw pointer. diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs index 88e5208369e40bdeebc6f758e89f836a97790d89..26b7272424aafdd4847d9642456= cab837797ac33 100644 --- a/rust/kernel/sync/arc.rs +++ b/rust/kernel/sync/arc.rs @@ -335,12 +335,12 @@ pub fn into_unique_or_drop(self) -> Option>> { impl ForeignOwnable for Arc { type Borrowed<'a> =3D ArcBorrow<'a, T>; =20 - fn into_foreign(self) -> *const core::ffi::c_void { - ManuallyDrop::new(self).ptr.as_ptr().cast_const().cast() + fn into_foreign(self) -> *mut core::ffi::c_void { + ManuallyDrop::new(self).ptr.as_ptr().cast() } =20 - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> ArcBorrow<'a, T= > { - let ptr =3D ptr.cast_mut().cast(); + unsafe fn borrow<'a>(ptr: *mut core::ffi::c_void) -> ArcBorrow<'a, T> { + let ptr =3D ptr.cast(); =20 // SAFETY: The safety requirements of this function ensure that `p= tr` comes from a previous // call to `Self::into_foreign`. @@ -351,8 +351,8 @@ unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> = ArcBorrow<'a, T> { unsafe { ArcBorrow::new(inner) } } =20 - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { - let ptr =3D ptr.cast_mut().cast(); + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self { + let ptr =3D ptr.cast(); =20 // SAFETY: The safety requirements of this function ensure that `p= tr` comes from a previous // call to `Self::into_foreign`. diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs index e8b7ff1387381e50d7963978e57b1d567113b035..04358375794dc5ba7bfebbe3cfc= 5885cff531f15 100644 --- a/rust/kernel/types.rs +++ b/rust/kernel/types.rs @@ -29,7 +29,7 @@ pub trait ForeignOwnable: Sized { /// For example, it might be invalid, dangling or pointing to uninitia= lized memory. Using it in /// any way except for [`ForeignOwnable::from_foreign`], [`ForeignOwna= ble::borrow`], /// [`ForeignOwnable::try_from_foreign`] can result in undefined behav= ior. - fn into_foreign(self) -> *const core::ffi::c_void; + fn into_foreign(self) -> *mut core::ffi::c_void; =20 /// Borrows a foreign-owned object. /// @@ -37,7 +37,7 @@ pub trait ForeignOwnable: Sized { /// /// `ptr` must have been returned by a previous call to [`ForeignOwnab= le::into_foreign`] for /// which a previous matching [`ForeignOwnable::from_foreign`] hasn't = been called yet. - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> Self::Borrowed<= 'a>; + unsafe fn borrow<'a>(ptr: *mut core::ffi::c_void) -> Self::Borrowed<'a= >; =20 /// Converts a foreign-owned object back to a Rust-owned one. /// @@ -47,7 +47,7 @@ pub trait ForeignOwnable: Sized { /// which a previous matching [`ForeignOwnable::from_foreign`] hasn't = been called yet. /// Additionally, all instances (if any) of values returned by [`Forei= gnOwnable::borrow`] for /// this object must have been dropped. - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self; + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self; =20 /// Tries to convert a foreign-owned object back to a Rust-owned one. /// @@ -58,7 +58,7 @@ pub trait ForeignOwnable: Sized { /// /// `ptr` must either be null or satisfy the safety requirements for /// [`ForeignOwnable::from_foreign`]. - unsafe fn try_from_foreign(ptr: *const core::ffi::c_void) -> Option { + unsafe fn try_from_foreign(ptr: *mut core::ffi::c_void) -> Option { if ptr.is_null() { None } else { @@ -72,13 +72,13 @@ unsafe fn try_from_foreign(ptr: *const core::ffi::c_voi= d) -> Option { impl ForeignOwnable for () { type Borrowed<'a> =3D (); =20 - fn into_foreign(self) -> *const core::ffi::c_void { + fn into_foreign(self) -> *mut core::ffi::c_void { core::ptr::NonNull::dangling().as_ptr() } =20 - unsafe fn borrow<'a>(_: *const core::ffi::c_void) -> Self::Borrowed<'a= > {} + unsafe fn borrow<'a>(_: *mut core::ffi::c_void) -> Self::Borrowed<'a> = {} =20 - unsafe fn from_foreign(_: *const core::ffi::c_void) -> Self {} + unsafe fn from_foreign(_: *mut core::ffi::c_void) -> Self {} } =20 /// Runs a cleanup function/closure when dropped. --=20 2.47.0