diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | samples/rust/Kconfig | 11 | ||||
| -rw-r--r-- | samples/rust/Makefile | 1 | ||||
| -rw-r--r-- | samples/rust/rust_debugfs_scoped.rs | 134 |
4 files changed, 147 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 4c471251a304..c01599d1727c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7497,6 +7497,7 @@ F: rust/kernel/driver.rs F: rust/kernel/faux.rs F: rust/kernel/platform.rs F: samples/rust/rust_debugfs.rs +F: samples/rust/rust_debugfs_scoped.rs F: samples/rust/rust_driver_platform.rs F: samples/rust/rust_driver_faux.rs diff --git a/samples/rust/Kconfig b/samples/rust/Kconfig index 01101db41ae3..66360cdf048f 100644 --- a/samples/rust/Kconfig +++ b/samples/rust/Kconfig @@ -73,6 +73,17 @@ config SAMPLE_RUST_DEBUGFS If unsure, say N. +config SAMPLE_RUST_DEBUGFS_SCOPED + tristate "Scoped DebugFS Test Module" + depends on DEBUG_FS + help + This option builds the Rust Scoped DebugFS Test module sample. + + To compile this as a module, choose M here: + the module will be called rust_debugfs_scoped. + + If unsure, say N. + config SAMPLE_RUST_DRIVER_PCI tristate "PCI Driver" depends on PCI diff --git a/samples/rust/Makefile b/samples/rust/Makefile index 61276222a99f..69ca01497b58 100644 --- a/samples/rust/Makefile +++ b/samples/rust/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_SAMPLE_RUST_MINIMAL) += rust_minimal.o obj-$(CONFIG_SAMPLE_RUST_MISC_DEVICE) += rust_misc_device.o obj-$(CONFIG_SAMPLE_RUST_PRINT) += rust_print.o obj-$(CONFIG_SAMPLE_RUST_DEBUGFS) += rust_debugfs.o +obj-$(CONFIG_SAMPLE_RUST_DEBUGFS_SCOPED) += rust_debugfs_scoped.o obj-$(CONFIG_SAMPLE_RUST_DMA) += rust_dma.o obj-$(CONFIG_SAMPLE_RUST_DRIVER_PCI) += rust_driver_pci.o obj-$(CONFIG_SAMPLE_RUST_DRIVER_PLATFORM) += rust_driver_platform.o diff --git a/samples/rust/rust_debugfs_scoped.rs b/samples/rust/rust_debugfs_scoped.rs new file mode 100644 index 000000000000..b0c4e76b123e --- /dev/null +++ b/samples/rust/rust_debugfs_scoped.rs @@ -0,0 +1,134 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Copyright (C) 2025 Google LLC. + +//! Sample DebugFS exporting platform driver that demonstrates the use of +//! `Scope::dir` to create a variety of files without the need to separately +//! track them all. + +use core::sync::atomic::AtomicUsize; +use kernel::debugfs::{Dir, Scope}; +use kernel::prelude::*; +use kernel::sync::Mutex; +use kernel::{c_str, new_mutex, str::CString}; + +module! { + type: RustScopedDebugFs, + name: "rust_debugfs_scoped", + authors: ["Matthew Maurer"], + description: "Rust Scoped DebugFS usage sample", + license: "GPL", +} + +fn remove_file_write( + mod_data: &ModuleData, + reader: &mut kernel::uaccess::UserSliceReader, +) -> Result { + let mut buf = [0u8; 128]; + if reader.len() >= buf.len() { + return Err(EINVAL); + } + let n = reader.len(); + reader.read_slice(&mut buf[..n])?; + + let s = core::str::from_utf8(&buf[..n]).map_err(|_| EINVAL)?.trim(); + let nul_idx = s.len(); + buf[nul_idx] = 0; + let to_remove = CStr::from_bytes_with_nul(&buf[..nul_idx + 1]).map_err(|_| EINVAL)?; + mod_data + .devices + .lock() + .retain(|device| device.name.as_bytes() != to_remove.as_bytes()); + Ok(()) +} + +fn create_file_write( + mod_data: &ModuleData, + reader: &mut kernel::uaccess::UserSliceReader, +) -> Result { + let mut buf = [0u8; 128]; + if reader.len() > buf.len() { + return Err(EINVAL); + } + let n = reader.len(); + reader.read_slice(&mut buf[..n])?; + + let mut nums = KVec::new(); + + let s = core::str::from_utf8(&buf[..n]).map_err(|_| EINVAL)?.trim(); + let mut items = s.split_whitespace(); + let name_str = items.next().ok_or(EINVAL)?; + let name = CString::try_from_fmt(fmt!("{name_str}"))?; + let file_name = CString::try_from_fmt(fmt!("{name_str}"))?; + for sub in items { + nums.push( + AtomicUsize::new(sub.parse().map_err(|_| EINVAL)?), + GFP_KERNEL, + )?; + } + + let scope = KBox::pin_init( + mod_data + .device_dir + .scope(DeviceData { name, nums }, &file_name, |dev_data, dir| { + for (idx, val) in dev_data.nums.iter().enumerate() { + let Ok(name) = CString::try_from_fmt(fmt!("{idx}")) else { + return; + }; + dir.read_write_file(&name, val); + } + }), + GFP_KERNEL, + )?; + (*mod_data.devices.lock()).push(scope, GFP_KERNEL)?; + + Ok(()) +} + +struct RustScopedDebugFs { + _data: Pin<KBox<Scope<ModuleData>>>, +} + +#[pin_data] +struct ModuleData { + device_dir: Dir, + #[pin] + devices: Mutex<KVec<Pin<KBox<Scope<DeviceData>>>>>, +} + +impl ModuleData { + fn init(device_dir: Dir) -> impl PinInit<Self> { + pin_init! { + Self { + device_dir: device_dir, + devices <- new_mutex!(KVec::new()) + } + } + } +} + +struct DeviceData { + name: CString, + nums: KVec<AtomicUsize>, +} + +fn init_control(base_dir: &Dir, dyn_dirs: Dir) -> impl PinInit<Scope<ModuleData>> + '_ { + base_dir.scope( + ModuleData::init(dyn_dirs), + c_str!("control"), + |data, dir| { + dir.write_only_callback_file(c_str!("create"), data, &create_file_write); + dir.write_only_callback_file(c_str!("remove"), data, &remove_file_write); + }, + ) +} + +impl kernel::Module for RustScopedDebugFs { + fn init(_module: &'static kernel::ThisModule) -> Result<Self> { + let base_dir = Dir::new(c_str!("rust_scoped_debugfs")); + let dyn_dirs = base_dir.subdir(c_str!("dynamic")); + Ok(Self { + _data: KBox::pin_init(init_control(&base_dir, dyn_dirs), GFP_KERNEL)?, + }) + } +} |