Parameterize the Adapter trait with a lifetime, changing the id_info(), of_id_info() and acpi_id_info() methods to take &'bound Device<Bound> and return &'bound Self::IdInfo instead of &'static.
This is needed for the ForLt conversion of bus driver traits. Once Driver becomes lifetime-parameterized, its IdInfo associated type may depend on the lifetime parameter. With Adapter<'bound>, the impl can set IdInfo = <F::Of<'bound> as Driver<'bound>>::IdInfo and the lifetime flows through naturally, avoiding the need for transmute. For the current non-lifetime-parameterized Driver trait, this is a no-op type relaxation; IdInfo is 'static and &'static coerces to &'bound. Signed-off-by: Danilo Krummrich <[email protected]> --- rust/kernel/driver.rs | 16 ++++++++++------ rust/kernel/i2c.rs | 10 +++++----- rust/kernel/platform.rs | 4 ++-- 3 files changed, 17 insertions(+), 13 deletions(-) diff --git a/rust/kernel/driver.rs b/rust/kernel/driver.rs index 2ab3c0050117..e462535f545d 100644 --- a/rust/kernel/driver.rs +++ b/rust/kernel/driver.rs @@ -96,7 +96,11 @@ use crate::{ acpi, - device, + device::{ + self, + Bound, + Device, // + }, of, prelude::*, types::{ @@ -192,7 +196,7 @@ extern "C" fn post_unbind_callback(dev: *mut bindings::device) { // a `struct device`. // // INVARIANT: `dev` is valid for the duration of the `post_unbind_callback()`. - let dev = unsafe { &*dev.cast::<device::Device<device::CoreInternal>>() }; + let dev = unsafe { &*dev.cast::<Device<device::CoreInternal>>() }; // `remove()` has been completed at this point; devres resources are still valid and will // be released after the driver's bus device private data is dropped. @@ -309,7 +313,7 @@ unsafe fn acpi_of_match_device( /// of a device and a driver. /// /// It provides bus independent functions for device / driver interactions. -pub trait Adapter { +pub trait Adapter<'bound> { /// The type holding driver private data about each device id supported by the driver. type IdInfo: 'static; @@ -319,7 +323,7 @@ pub trait Adapter { /// Returns the driver's private data from the matching entry in the [`acpi::IdTable`], if any. /// /// If this returns `None`, it means there is no match with an entry in the [`acpi::IdTable`]. - fn acpi_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { + fn acpi_id_info(dev: &'bound Device<Bound>) -> Option<&'bound Self::IdInfo> { #[cfg(not(CONFIG_ACPI))] { let _ = dev; @@ -353,7 +357,7 @@ fn acpi_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { /// Returns the driver's private data from the matching entry in the [`of::IdTable`], if any. /// /// If this returns `None`, it means there is no match with an entry in the [`of::IdTable`]. - fn of_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { + fn of_id_info(dev: &'bound Device<Bound>) -> Option<&'bound Self::IdInfo> { let table = Self::of_id_table()?; #[cfg(not(any(CONFIG_OF, CONFIG_ACPI)))] @@ -417,7 +421,7 @@ fn of_id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { /// /// If this returns `None`, it means that there is no match in any of the ID tables directly /// associated with a [`device::Device`]. - fn id_info(dev: &device::Device) -> Option<&'static Self::IdInfo> { + fn id_info(dev: &'bound Device<Bound>) -> Option<&'bound Self::IdInfo> { let id = Self::acpi_id_info(dev); if id.is_some() { return id; diff --git a/rust/kernel/i2c.rs b/rust/kernel/i2c.rs index cde3dd7a6cc7..208c73aa3ce3 100644 --- a/rust/kernel/i2c.rs +++ b/rust/kernel/i2c.rs @@ -162,8 +162,8 @@ extern "C" fn probe_callback(idev: *mut bindings::i2c_client) -> kernel::ffi::c_ // INVARIANT: `idev` is valid for the duration of `probe_callback()`. let idev = unsafe { &*idev.cast::<I2cClient<device::CoreInternal>>() }; - let info = - Self::i2c_id_info(idev).or_else(|| <Self as driver::Adapter>::id_info(idev.as_ref())); + let info = Self::i2c_id_info(idev) + .or_else(|| <Self as driver::Adapter<'_>>::id_info(idev.as_ref())); from_result(|| { let data = T::probe(idev, info); @@ -198,14 +198,14 @@ extern "C" fn shutdown_callback(idev: *mut bindings::i2c_client) { } /// The [`i2c::IdTable`] of the corresponding driver. - fn i2c_id_table() -> Option<IdTable<<Self as driver::Adapter>::IdInfo>> { + fn i2c_id_table() -> Option<IdTable<<Self as driver::Adapter<'static>>::IdInfo>> { T::I2C_ID_TABLE } /// Returns the driver's private data from the matching entry in the [`i2c::IdTable`], if any. /// /// If this returns `None`, it means there is no match with an entry in the [`i2c::IdTable`]. - fn i2c_id_info(dev: &I2cClient) -> Option<&'static <Self as driver::Adapter>::IdInfo> { + fn i2c_id_info(dev: &I2cClient) -> Option<&'static <Self as driver::Adapter<'static>>::IdInfo> { let table = Self::i2c_id_table()?; // SAFETY: @@ -225,7 +225,7 @@ fn i2c_id_info(dev: &I2cClient) -> Option<&'static <Self as driver::Adapter>::Id } } -impl<T: Driver + 'static> driver::Adapter for Adapter<T> { +impl<'bound, T: Driver + 'static> driver::Adapter<'bound> for Adapter<T> { type IdInfo = T::IdInfo; fn of_id_table() -> Option<of::IdTable<Self::IdInfo>> { diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs index 7ff69e3eea90..506731a648c2 100644 --- a/rust/kernel/platform.rs +++ b/rust/kernel/platform.rs @@ -101,7 +101,7 @@ extern "C" fn probe_callback(pdev: *mut bindings::platform_device) -> kernel::ff // // INVARIANT: `pdev` is valid for the duration of `probe_callback()`. let pdev = unsafe { &*pdev.cast::<Device<device::CoreInternal>>() }; - let info = <Self as driver::Adapter>::id_info(pdev.as_ref()); + let info = <Self as driver::Adapter<'_>>::id_info(pdev.as_ref()); from_result(|| { let data = T::probe(pdev, info); @@ -127,7 +127,7 @@ extern "C" fn remove_callback(pdev: *mut bindings::platform_device) { } } -impl<T: Driver + 'static> driver::Adapter for Adapter<T> { +impl<'bound, T: Driver + 'static> driver::Adapter<'bound> for Adapter<T> { type IdInfo = T::IdInfo; fn of_id_table() -> Option<of::IdTable<Self::IdInfo>> { -- 2.54.0
