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> use gem::{ > BaseObjectPrivate, > @@ -244,3 +247,29 @@ impl driver::Allo= cImpl for Object { > dumb_map_offset: None, > }; > } > + > +/// Private helper-type for holding the `dma_resv` object for a GEM shme= m object. > +/// > +/// When this is dropped, the `dma_resv` lock is dropped as well. > +/// > +// TODO: This should be replace with a WwMutex equivalent once we have s= uch bindings in the kernel. > +struct DmaResvGuard<'a, T: DriverObject, C: DeviceContext =3D Registered= >(&'a Object); > + > +impl<'a, T: DriverObject, C: DeviceContext> DmaResvGuard<'a, T, C> { > + #[inline(always)] Why `always` here? Best, Gary > + #[expect(unused)] > + fn new(obj: &'a Object) -> Self { > + // SAFETY: This lock is initialized throughout the lifetime of `= object`. > + unsafe { bindings::dma_resv_lock(obj.raw_dma_resv(), ptr::null_m= ut()) }; > + > + Self(obj) > + } > +} > + > +impl<'a, T: DriverObject, C: DeviceContext> Drop for DmaResvGuard<'a, T,= C> { > + #[inline(always)] > + fn drop(&mut self) { > + // SAFETY: We are releasing the lock grabbed during the creation= of this object. > + unsafe { bindings::dma_resv_unlock(self.0.raw_dma_resv()) }; > + } > +}