This adds support for creating a DebugFS directory which is aware that it is bound to a device. As a result, callbacks under that directory have access to a bound device which gives them efficient access to other Devres, ability to use dev_err! and friends, etc.
Signed-off-by: Matthew Maurer <[email protected]> --- rust/kernel/debugfs.rs | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/rust/kernel/debugfs.rs b/rust/kernel/debugfs.rs index d7b8014a6474698235203f2b7d8fec96f2bb43f8..ac614d693fa73929d095b669e9ba61958bec609e 100644 --- a/rust/kernel/debugfs.rs +++ b/rust/kernel/debugfs.rs @@ -11,6 +11,11 @@ #[cfg(CONFIG_DEBUG_FS)] use crate::sync::Arc; use crate::{ + device::{ + Bound, + Device, // + }, + devres::Devres, fmt, prelude::*, str::CStr, @@ -722,3 +727,38 @@ fn new(name: &CStr) -> ScopedDir<'data, 'static> { } } } + +impl<'a, T: 'a + Send> Devres<Scope<T>> { + /// Creates a new scope, which is a directory at the root of the debugfs filesystem, + /// associated with some data `T`, enclosed in a [`Devres`] for the provided device. + /// + /// The `init` closure is called to populate the directory with files and subdirectories. These + /// files can reference the data stored in the scope. Because it is stored inside a `Devres`, + /// the init method is granted access to a `&Device<Bound>`. + /// + /// This can be used for cheaply accessing device-protected data inside DebugFS methods or + /// accessing device-specific methods (e.g. [`dev_err!`]). + /// + /// The entire directory tree created within the scope will be removed when the returned + /// `Scope` handle is dropped. + pub fn dir<E: 'a, F>( + dev: &'a Device<Bound>, + data: impl PinInit<T, E> + 'a, + name: &'a CStr, + init: F, + ) -> impl PinInit<Self, Error> + 'a + where + F: for<'data, 'dir> FnOnce(&'data T, &'data Device<Bound>, &'dir ScopedDir<'data, 'dir>) + + 'a, + Error: From<E>, + { + Devres::new( + dev, + Scope::new(data, |data| { + let scoped = ScopedDir::new(name); + init(data, dev, &scoped); + scoped.into_entry() + }), + ) + } +} -- 2.53.0.rc2.204.g2597b5adb4-goog
