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Signed-off-by: Tamir Duberstein Reviewed-by: Andreas Hindborg Reviewed-by: Alice Ryhl --- 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 b6b6723098b6b30743bf38c97aab0e701a5a1be4..99d0fc0148bb8779e5a769a6e74= 291ef8101bf77 100644 --- a/rust/kernel/alloc/kbox.rs +++ b/rust/kernel/alloc/kbox.rs @@ -355,17 +355,17 @@ 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 { + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self { // 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.cast_mut().cast()) } + unsafe { Box::from_raw(ptr.cast()) } } =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 { // SAFETY: The safety requirements of this method ensure that the = object remains alive and // immutable for the duration of 'a. unsafe { &*ptr.cast() } @@ -378,20 +378,18 @@ 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 { + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self { // 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.cast_mut().cast())) } + unsafe { Pin::new_unchecked(Box::from_raw(ptr.cast())) } } =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> { // SAFETY: The safety requirements for this function ensure that t= he object is still alive, // so it is safe to dereference the raw pointer. // The safety requirements of `from_foreign` also ensure that the = object remains alive for diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs index 9adea755a5ad1a7b03f7fc30a7abc76c1f966c6c..10819dc28b64038b9abc55b01c0= 69826d1e5befa 100644 --- a/rust/kernel/sync/arc.rs +++ b/rust/kernel/sync/arc.rs @@ -333,24 +333,24 @@ 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= > { + unsafe fn borrow<'a>(ptr: *mut core::ffi::c_void) -> ArcBorrow<'a, T> { // SAFETY: The safety requirements of this function ensure that `p= tr` comes from a previous // call to `Self::into_foreign`. - let inner =3D unsafe { NonNull::new_unchecked(ptr.cast_mut().cast:= :>()) }; + let inner =3D unsafe { NonNull::new_unchecked(ptr.cast::>()) }; =20 // SAFETY: The safety requirements of `from_foreign` ensure that t= he object remains alive // for the lifetime of the returned value. unsafe { ArcBorrow::new(inner) } } =20 - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { + unsafe fn from_foreign(ptr: *mut core::ffi::c_void) -> Self { // SAFETY: The safety requirements of this function ensure that `p= tr` comes from a previous // call to `Self::into_foreign`. - let inner =3D unsafe { NonNull::new_unchecked(ptr.cast_mut().cast:= :>()) }; + let inner =3D unsafe { NonNull::new_unchecked(ptr.cast::>()) }; =20 // SAFETY: By the safety requirement of this function, we know tha= t `ptr` came from // a previous call to `Arc::into_foreign`, which guarantees that `= ptr` is valid and diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs index 364dd2dc438eb7d1c4d0a4525bf2305a42297b2b..59e71bd158713bb8e12cac95e13= 4f57a277c1b49 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