In the previous patch we added Opaque::cast_from() that performs the
opposite operation to Opaque::raw_get(). For consistency with this
naming, rename raw_get() to cast_from().
There are a few other options such as calling cast_from() something
closer to raw_get() rather than renaming this method. However, I could
not find a great naming scheme that works with raw_get(). The previous
version of this patch used from_raw(), but functions of that name
typically have a different signature, so that's not a great option.
Suggested-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Benno Lossin <lossin@kernel.org>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250624-opaque-from-raw-v2-2-e4da40bdc59c@google.com
[ Removed `HrTimer::raw_get` change. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In Rust 1.51.0, Clippy introduced the `ptr_as_ptr` lint [1]:
> Though `as` casts between raw pointers are not terrible,
> `pointer::cast` is safer because it cannot accidentally change the
> pointer's mutability, nor cast the pointer to other types like `usize`.
There are a few classes of changes required:
- Modules generated by bindgen are marked
`#[allow(clippy::ptr_as_ptr)]`.
- Inferred casts (` as _`) are replaced with `.cast()`.
- Ascribed casts (` as *... T`) are replaced with `.cast::<T>()`.
- Multistep casts from references (` as *const _ as *const T`) are
replaced with `core::ptr::from_ref(&x).cast()` with or without `::<T>`
according to the previous rules. The `core::ptr::from_ref` call is
required because `(x as *const _).cast::<T>()` results in inference
failure.
- Native literal C strings are replaced with `c_str!().as_char_ptr()`.
- `*mut *mut T as _` is replaced with `let *mut *const T = (*mut *mut
T)`.cast();` since pointer to pointer can be confusing.
Apply these changes and enable the lint -- no functional change
intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_as_ptr [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-1-f43b024581e8@gmail.com
[ Added `.cast()` for `opp`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Fix a compile error in the `impl_has_hr_timer!` macro as follows:
error[E0599]: no method named cast_mut found for raw pointer *mut Foo in the current scope
The `container_of!` macro already returns a mutable pointer when used
in a `*mut T` context so the `.cast_mut()` method is not available.
[ We missed this one because there is no caller yet and it is
a macro. - Miguel ]
Fixes: 74d6a606c2 ("rust: retain pointer mut-ness in `container_of!`")
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250606020505.3186533-1-fujita.tomonori@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`bindgen` currently generates the wrong type for an `enum` when there
is a forward reference to it. For instance:
enum E;
enum E { A };
generates:
pub const E_A: E = 0;
pub type E = i32;
instead of the expected:
pub const E_A: E = 0;
pub type E = ffi::c_uint;
The issue was reported to upstream `bindgen` [1].
Now, both GCC and Clang support silently these forward references to
`enum` types, unless `-Wpedantic` is passed, and it turns out that some
headers in the kernel depend on them.
Thus, depending on how the headers are included, which in turn may depend
on the kernel configuration or the architecture, we may get a different
type on the Rust side for a given C `enum`.
That can be quite confusing, to say the least, especially since
developers may only notice issues when building for other architectures
like in [2]. In particular, they may end up forcing a cast and adding
an `#[allow(clippy::unnecessary_cast)]` like it was done in commit
94e05a66ea ("rust: hrtimer: allow timer restart from timer handler"),
which isn't great.
Instead, let's have a section at the top of our `bindings_helper.h` that
`#include`s the headers with the affected types -- hopefully there are
not many cases and there is a single ordering that covers all cases.
This allows us to remove the cast and the `#[allow]`, thus keeping the
correct code in the source files. When the issue gets resolved in upstream
`bindgen` (and we update our minimum `bindgen` version), we can easily
remove this section at the top.
Link: https://github.com/rust-lang/rust-bindgen/issues/3179 [1]
Link: https://lore.kernel.org/rust-for-linux/87tt7md1s6.fsf@kernel.org/ [2]
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250325184309.97170-1-ojeda@kernel.org
[ Added extra paragraph on the comment to clarify that the workaround may
not be possible in some cases. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull rust-hrtimer updates from Andreas Hindborg:
"Introduce Rust support for the 'hrtimer' subsystem:
- Add a way to use the 'hrtimer' subsystem from Rust. Rust code can
now set up intrusive timers without allocating when starting the
timer.
- Add support for 'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and
'Pin<&mut _>' as pointer types for use with timer callbacks.
- Add support for setting clock source and timer mode.
'kernel' crate:
- Add 'Arc::as_ptr' for converting an 'Arc' to a raw pointer. This is
a dependency for the 'hrtimer' API.
- Add 'Box::into_pin' for converting a 'Box<_>' into a 'Pin<Box<_>>'
to align with Rust 'alloc'. This is a dependency for the 'hrtimer'
API."
* tag 'rust-hrtimer-for-v6.15-v3' of https://github.com/Rust-for-Linux/linux:
rust: hrtimer: add maintainer entry
rust: hrtimer: add clocksource selection through `ClockId`
rust: hrtimer: add `HrTimerMode`
rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
rust: alloc: add `Box::into_pin`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
rust: hrtimer: add `UnsafeHrTimerPointer`
rust: hrtimer: allow timer restart from timer handler
rust: hrtimer: implement `HrTimerPointer` for `Arc`
rust: sync: add `Arc::as_ptr`
rust: hrtimer: introduce hrtimer support
