// SPDX-License-Identifier: GPL-2.0 use super::HasHrTimer;use super::HrTimer;use super::HrTimerCallback;use super::HrTimerCallbackContext;use super::HrTimerHandle;use super::HrTimerMode;use super::HrTimerPointer;use super::RawHrTimerCallback;use crate::prelude::*;use core::ptr::NonNull; /// A handle for a [`Box<HasHrTimer<T>>`] returned by a call to/// [`HrTimerPointer::start`].////// # Invariants////// - `self.inner` comes from a `Box::into_raw` call.pub struct BoxHrTimerHandle<T, A>where    T: HasHrTimer<T>,    A: crate::alloc::Allocator,{    pub(crate) inner: NonNull<T>,    _p: core::marker::PhantomData<A>,} // SAFETY: We implement drop below, and we cancel the timer in the drop// implementation.unsafe impl<T, A> HrTimerHandle for BoxHrTimerHandle<T, A>where    T: HasHrTimer<T>,    A: crate::alloc::Allocator,{    fn cancel(&mut self) -> bool {        // SAFETY: As we obtained `self.inner` from a valid reference when we        // created `self`, it must point to a valid `T`.        let timer_ptr = unsafe { <T as HasHrTimer<T>>::raw_get_timer(self.inner.as_ptr()) };         // SAFETY: As `timer_ptr` points into `T` and `T` is valid, `timer_ptr`        // must point to a valid `HrTimer` instance.        unsafe { HrTimer::<T>::raw_cancel(timer_ptr) }    }} impl<T, A> Drop for BoxHrTimerHandle<T, A>where    T: HasHrTimer<T>,    A: crate::alloc::Allocator,{    fn drop(&mut self) {        self.cancel();        // SAFETY: By type invariant, `self.inner` came from a `Box::into_raw`        // call.        drop(unsafe { Box::<T, A>::from_raw(self.inner.as_ptr()) })    }} impl<T, A> HrTimerPointer for Pin<Box<T, A>>where    T: 'static,    T: Send + Sync,    T: HasHrTimer<T>,    T: for<'a> HrTimerCallback<Pointer<'a> = Pin<Box<T, A>>>,    A: crate::alloc::Allocator,{    type TimerMode = <T as HasHrTimer<T>>::TimerMode;    type TimerHandle = BoxHrTimerHandle<T, A>;     fn start(        self,        expires: <<T as HasHrTimer<T>>::TimerMode as HrTimerMode>::Expires,    ) -> Self::TimerHandle {        // SAFETY:        //  - We will not move out of this box during timer callback (we pass an        //    immutable reference to the callback).        //  - `Box::into_raw` is guaranteed to return a valid pointer.        let inner =            unsafe { NonNull::new_unchecked(Box::into_raw(Pin::into_inner_unchecked(self))) };         // SAFETY:        //  - We keep `self` alive by wrapping it in a handle below.        //  - Since we generate the pointer passed to `start` from a valid        //    reference, it is a valid pointer.        unsafe { T::start(inner.as_ptr(), expires) };         // INVARIANT: `inner` came from `Box::into_raw` above.        BoxHrTimerHandle {            inner,            _p: core::marker::PhantomData,        }    }} impl<T, A> RawHrTimerCallback for Pin<Box<T, A>>where    T: 'static,    T: HasHrTimer<T>,    T: for<'a> HrTimerCallback<Pointer<'a> = Pin<Box<T, A>>>,    A: crate::alloc::Allocator,{    type CallbackTarget<'a> = Pin<&'a mut T>;     unsafe extern "C" fn run(ptr: *mut bindings::hrtimer) -> bindings::hrtimer_restart {        // `HrTimer` is `repr(C)`        let timer_ptr = ptr.cast::<super::HrTimer<T>>();         // SAFETY: By C API contract `ptr` is the pointer we passed when        // queuing the timer, so it is a `HrTimer<T>` embedded in a `T`.        let data_ptr = unsafe { T::timer_container_of(timer_ptr) };         // SAFETY:        //  - As per the safety requirements of the trait `HrTimerHandle`, the        //   `BoxHrTimerHandle` associated with this timer is guaranteed to        //   be alive until this method returns. That handle owns the `T`        //   behind `data_ptr` thus guaranteeing the validity of        //   the reference created below.        // - As `data_ptr` comes from a `Pin<Box<T>>`, only pinned references to        //   `data_ptr` exist.        let data_mut_ref = unsafe { Pin::new_unchecked(&mut *data_ptr) };         // SAFETY:        // - By C API contract `timer_ptr` is the pointer that we passed when queuing the timer, so        //   it is a valid pointer to a `HrTimer<T>` embedded in a `T`.        // - We are within `RawHrTimerCallback::run`        let context = unsafe { HrTimerCallbackContext::from_raw(timer_ptr) };         T::run(data_mut_ref, context).into_c()    }}