// 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::sync::Arc;use crate::sync::ArcBorrow; /// A handle for an `Arc<HasHrTimer<T>>` returned by a call to/// [`HrTimerPointer::start`].pub struct ArcHrTimerHandle<T>where    T: HasHrTimer<T>,{    pub(crate) inner: Arc<T>,} // SAFETY: We implement drop below, and we cancel the timer in the drop// implementation.unsafe impl<T> HrTimerHandle for ArcHrTimerHandle<T>where    T: HasHrTimer<T>,{    fn cancel(&mut self) -> bool {        let self_ptr = Arc::as_ptr(&self.inner);         // SAFETY: As we obtained `self_ptr` from a valid reference above, it        // must point to a valid `T`.        let timer_ptr = unsafe { <T as HasHrTimer<T>>::raw_get_timer(self_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> Drop for ArcHrTimerHandle<T>where    T: HasHrTimer<T>,{    fn drop(&mut self) {        self.cancel();    }} impl<T> HrTimerPointer for Arc<T>where    T: 'static,    T: Send + Sync,    T: HasHrTimer<T>,    T: for<'a> HrTimerCallback<Pointer<'a> = Self>,{    type TimerMode = <T as HasHrTimer<T>>::TimerMode;    type TimerHandle = ArcHrTimerHandle<T>;     fn start(        self,        expires: <<T as HasHrTimer<T>>::TimerMode as HrTimerMode>::Expires,    ) -> ArcHrTimerHandle<T> {        // 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(Arc::as_ptr(&self), expires) };        ArcHrTimerHandle { inner: self }    }} impl<T> RawHrTimerCallback for Arc<T>where    T: 'static,    T: HasHrTimer<T>,    T: for<'a> HrTimerCallback<Pointer<'a> = Self>,{    type CallbackTarget<'a> = ArcBorrow<'a, 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:        //  - `data_ptr` is derived form the pointer to the `T` that was used to        //    queue the timer.        //  - As per the safety requirements of the trait `HrTimerHandle`, the        //    `ArcHrTimerHandle` associated with this timer is guaranteed to        //    be alive until this method returns. That handle borrows the `T`        //    behind `data_ptr` thus guaranteeing the validity of        //    the `ArcBorrow` created below.        //  - We own one refcount in the `ArcTimerHandle` associated with this        //    timer, so it is not possible to get a `UniqueArc` to this        //    allocation from other `Arc` clones.        let receiver = unsafe { ArcBorrow::from_raw(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(receiver, context).into_c()    }}