Commit f720efda authored by Danilo Krummrich's avatar Danilo Krummrich
Browse files

rust: devres: require a bound device 

Require the Bound device context to be able to a new Devres container.
This ensures that we can't register devres callbacks for unbound
devices.

Link: https://lore.kernel.org/r/20250413173758.12068-9-dakr@kernel.org


Signed-off-by: default avatarDanilo Krummrich <dakr@kernel.org>
parent f2a399d7

rust/kernel/devres.rs

+7 −10
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ 
use crate::{

    alloc::Flags,

    bindings,

    device::Device,

    device::{Bound, Device},

    error::{Error, Result},

    ffi::c_void,

    prelude::*,
@@ -45,7 +45,7 @@ struct DevresInner<T> { 
/// # Example

///

/// ```no_run

/// # use kernel::{bindings, c_str, device::Device, devres::Devres, io::{Io, IoRaw}};

/// # use kernel::{bindings, c_str, device::{Bound, Device}, devres::Devres, io::{Io, IoRaw}};

/// # use core::ops::Deref;

///

/// // See also [`pci::Bar`] for a real example.
@@ -83,13 +83,10 @@ struct DevresInner<T> { 
///         unsafe { Io::from_raw(&self.0) }

///    }

/// }

/// # fn no_run() -> Result<(), Error> {

/// # // SAFETY: Invalid usage; just for the example to get an `ARef<Device>` instance.

/// # let dev = unsafe { Device::get_device(core::ptr::null_mut()) };

///

/// # fn no_run(dev: &Device<Bound>) -> Result<(), Error> {

/// // SAFETY: Invalid usage for example purposes.

/// let iomem = unsafe { IoMem::<{ core::mem::size_of::<u32>() }>::new(0xBAAAAAAD)? };

/// let devres = Devres::new(&dev, iomem, GFP_KERNEL)?;

/// let devres = Devres::new(dev, iomem, GFP_KERNEL)?;

///

/// let res = devres.try_access().ok_or(ENXIO)?;

/// res.write8(0x42, 0x0);
@@ -99,7 +96,7 @@ struct DevresInner<T> { 
pub struct Devres<T>(Arc<DevresInner<T>>);



impl<T> DevresInner<T> {

    fn new(dev: &Device, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> {

    fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> {

        let inner = Arc::pin_init(

            pin_init!( DevresInner {

                dev: dev.into(),
@@ -171,7 +168,7 @@ fn remove_action(this: &Arc<Self>) { 
impl<T> Devres<T> {

    /// Creates a new [`Devres`] instance of the given `data`. The `data` encapsulated within the

    /// returned `Devres` instance' `data` will be revoked once the device is detached.

    pub fn new(dev: &Device, data: T, flags: Flags) -> Result<Self> {

    pub fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Self> {

        let inner = DevresInner::new(dev, data, flags)?;



        Ok(Devres(inner))
@@ -179,7 +176,7 @@ pub fn new(dev: &Device, data: T, flags: Flags) -> Result<Self> { 


    /// Same as [`Devres::new`], but does not return a `Devres` instance. Instead the given `data`

    /// is owned by devres and will be revoked / dropped, once the device is detached.

    pub fn new_foreign_owned(dev: &Device, data: T, flags: Flags) -> Result {

    pub fn new_foreign_owned(dev: &Device<Bound>, data: T, flags: Flags) -> Result {

        let _ = DevresInner::new(dev, data, flags)?;



        Ok(())