* [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support
@ 2025-09-24 12:39 Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 1/7] rust: sync: add `SetOnce` Andreas Hindborg
` (8 more replies)
0 siblings, 9 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
Extend the `module!` macro with support module parameters. Also add some
string to integer parsing functions.
Based on the original module parameter support by Miguel [1],
later extended and generalized by Adam for more types [2][3].
Originally tracked at [4].
Link: https://github.com/Rust-for-Linux/linux/pull/7 [1]
Link: https://github.com/Rust-for-Linux/linux/pull/82 [2]
Link: https://github.com/Rust-for-Linux/linux/pull/87 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/11 [4]
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
Changes in v18:
- Rebase on Rust atomic patches (tip/master).
- Link to v17: https://lore.kernel.org/r/20250711-module-params-v3-v17-0-cf9b10d4923d@kernel.org
Changes in v17:
- Fix drop impl of `SetOnce` so that it works with `UnsafeCell<MaybeUninit<_>>`.
- Slightly reword safety framework in `SetOnce`.
- Rebase on atomic series v6.
- Link to v16: https://lore.kernel.org/r/20250709-module-params-v3-v16-0-4f926bcccb50@kernel.org
Changes in v16:
- Normalize imports in `set_once.rs`.
- Use `UnsafeCell<MaybeUninit<T>>` rather than `Opaque<T>` for `SetOnce`.
- Use regular load in drop of `SetOnce`.
- Update attribution paragraph in cover letter with details from Miguel.
- Remove stray TODO in `set_once.rs`
- Link to v15: https://lore.kernel.org/r/20250707-module-params-v3-v15-0-c1f4269a57b9@kernel.org
Changes in v15:
- Rebase on v6.16-rc5.
- Dedent code in module macro for better formatting.
- Rename `OnceLock` to `SetOnce`.
- Use "being initialized" rather than "being mutably accessed" when
describing initialization state of `OnceLock`.
- Use `Relaxed` ordering when transitioning to exclusive access in
`OnceLock`.
- Add drop implementation for `OnceLock`.
- Re-export `OnceLock` from `kernel::sync` module.
- Improve indentation of in macro code. Prefix `cfg` to `::core::cfg` in
macro code.
- Use `core::ptr::from_ref` rather than `as` casts.
- Hide `KernelParam` instances behind `const _: ()` blocks.
- Rename `ModuleParamAccess::get` to `ModuleParamAccess::value`.
- Rename `RacyKernelParam` to `KernelParam`.
- Remove `ModuleParam::Value`.
- Move `copy` implementation of `OnceLock`.
- Update safety comments and invariants of `OnceLock`.
- Link to v14: https://lore.kernel.org/r/20250702-module-params-v3-v14-0-5b1cc32311af@kernel.org
Note: This series now depends on the atomics series [1].
[1] https://lore.kernel.org/all/20250618164934.19817-1-boqun.feng@gmail.com
Changes in v14:
- Remove unnecessary `crate::` prefix from `module_param::set_param`.
- Make `FromStrRadix` safe again by moving unsafe blocks to macro implementation (thanks Benno).
- Use `core::ptr::write` in `set_param` and drop safety requirement regarding initialization.
- Add a TODO to use `SyncUnsafeCell` for `ModuleParamAccess` when available.
- Add a NOTE regarding `Copy` bound on `ModuleParam`.
- Remove `'static` lifetime qualifier from `ModuleParam::try_from_param_arg` argument.
- Fix a typo in the safety requirements for `set_param`.
- Remove unused `#[macro_export]` attribute.
- Remove obsolete documentation for `ModuleParam::try_from_param_arg`.
- Make `RacyKernelParam` tuple field private.
- Introduce `OnceLock` and use that to synchronize population of parameter values.
- Link to v13: https://lore.kernel.org/r/20250612-module-params-v3-v13-0-bc219cd1a3f8@kernel.org
Changes in v13:
- remove absolute path for `ffi` types.
- Split patch 2 into 4 separate patches.
- Overhaul safety framework for `set_param`.
- Remove generated docs for `kernel_param_ops`.
- Move `parse_int` to separate file.
- Rebase on v6.16-rc1
- Link to v12: https://lore.kernel.org/r/20250506-module-params-v3-v12-0-c04d80c8a2b1@kernel.org
Changes in v12:
- Assign through pointer rather than using `core::ptr::replace`.
- Prevent a potential use-after-free during module teardown.
- Link to v11: https://lore.kernel.org/r/20250502-module-params-v3-v11-0-6096875a2b78@kernel.org
Changes in v11:
- Apply a few nits from Miguel.
- Link to v10: https://lore.kernel.org/r/20250501-module-params-v3-v10-0-4da485d343d5@kernel.org
Changes in v10:
- Apply fixups from Miguel:
- Add integer type suffixes to `assert!` in tests.
- Fix links to docs.kernel.org.
- Applyy markdown and intra-doc links where possible.
- Change to `///` for `mod` docs.
- Slightly reword a comment.
- Pluralize "Examples" section name.
- Hide `use`s in example.
- Removed `#[expect]` for the `rusttest` target.
- Link to v9: https://lore.kernel.org/r/20250321-module-params-v3-v9-0-28b905f2e345@kernel.org
Changes in v9:
- Remove UB when parsing the minimum integer values.
- Make `FromStr` trait unsafe, since wrong implementations can cause UB.
- Drop patches that were applied to rust-next.
- Link to v8: https://lore.kernel.org/r/20250227-module-params-v3-v8-0-ceeee85d9347@kernel.org
Changes in v8:
- Change print statement in sample to better communicate parameter name.
- Use imperative mode in commit messages.
- Remove prefix path from `EINVAL`.
- Change `try_from_param_arg` to accept `&BStr` rather than `&[u8]`.
- Parse integers without 128 bit integer types.
- Seal trait `FromStrRadix`.
- Strengthen safety requirement of `set_param`.
- Remove comment about Display and `PAGE_SIZE`.
- Add note describing why `ModuleParamAccess` is pub.
- Typo and grammar fixes for documentation.
- Update MAINTAINERS with rust module files.
- Link to v7: https://lore.kernel.org/r/20250218-module-params-v3-v7-0-5e1afabcac1b@kernel.org
Changes in v7:
- Remove dependency on `pr_warn_once` patches, replace with TODO.
- Rework `ParseInt::from_str` to avoid allocating.
- Add a comment explaining how we parse "0".
- Change trait bound on `Index` impl for `BStr` to match std library approach.
- Link to v6: https://lore.kernel.org/r/20250211-module-params-v3-v6-0-24b297ddc43d@kernel.org
Changes in v6:
- Fix a bug that prevented parsing of negative default values for
parameters in the `module!` macro.
- Fix a bug that prevented parsing zero in `strip_radix`. Also add a
test case for this.
- Add `AsRef<BStr>` for `[u8]` and `BStr`.
- Use `impl AsRef<BStr>` as type of prefix in `BStr::strip_prefix`.
- Link to v5: https://lore.kernel.org/r/20250204-module-params-v3-v5-0-bf5ec2041625@kernel.org
Changes in v5:
- Fix a typo in a safety comment in `set_param`.
- Use a match statement in `parse_int::strip_radix`.
- Add an implementation of `Index` for `BStr`.
- Fix a logic inversion bug where parameters would not be parsed.
- Use `kernel::ffi::c_char` in `set_param` rather than the one in `core`.
- Use `kernel::c_str!` rather than `c"..."` literal in module macro.
- Rebase on v6.14-rc1.
- Link to v4: https://lore.kernel.org/r/20250109-module-params-v3-v4-0-c208bcfbe11f@kernel.org
Changes in v4:
- Add module maintainers to Cc list (sorry)
- Add a few missing [`doc_links`]
- Add panic section to `expect_string_field`
- Fix a typo in safety requirement of `module_params::free`
- Change `assert!` to `pr_warn_once!` in `module_params::set_param`
- Remove `module_params::get_param` and install null pointer instead
- Remove use of the unstable feature `sync_unsafe_cell`
- Link to v3: https://lore.kernel.org/r/20241213-module-params-v3-v3-0-485a015ac2cf@kernel.org
Changes in v3:
- use `SyncUnsafeCell` rather than `static mut` and simplify parameter access
- remove `Display` bound from `ModuleParam`
- automatically generate documentation for `PARAM_OPS_.*`
- remove `as *const _ as *mut_` phrasing
- inline parameter name in struct instantiation in `emit_params`
- move `RacyKernelParam` out of macro template
- use C string literals rather than byte string literals with explicit null
- template out `__{name}_{param_name}` in `emit_param`
- indent template in `emit_params`
- use let-else expression in `emit_params` to get rid of an indentation level
- document `expect_string_field`
- move invication of `impl_int_module_param` to be closer to macro def
- move attributes after docs in `make_param_ops`
- rename `impl_module_param` to impl_int_module_param`
- use `ty` instead of `ident` in `impl_parse_int`
- use `BStr` instead of `&str` for string manipulation
- move string parsing functions to seperate patch and add examples, fix bugs
- degrade comment about future support from doc comment to regular comment
- remove std lib path from `Sized` marker
- update documentation for `trait ModuleParam`
- Link to v2: https://lore.kernel.org/all/20240819133345.3438739-1-nmi@metaspace.dk/
Changes in v2:
- Remove support for params without values (`NOARG_ALLOWED`).
- Improve documentation for `try_from_param_arg`.
- Use prelude import.
- Refactor `try_from_param_arg` to return `Result`.
- Refactor `ParseInt::from_str` to return `Result`.
- Move C callable functions out of `ModuleParam` trait.
- Rename literal string field parser to `expect_string_field`.
- Move parameter parsing from generation to parsing stage.
- Use absolute type paths in macro code.
- Inline `kparam`and `read_func` values.
- Resolve TODO regarding alignment attributes.
- Remove unnecessary unsafe blocks in macro code.
- Improve error message for unrecognized parameter types.
- Do not use `self` receiver when reading parameter value.
- Add parameter documentation to `module!` macro.
- Use empty `enum` for parameter type.
- Use `addr_of_mut` to get address of parameter value variable.
- Enabled building of docs for for `module_param` module.
- Link to v1: https://lore.kernel.org/rust-for-linux/20240705111455.142790-1-nmi@metaspace.dk/
---
Andreas Hindborg (7):
rust: sync: add `SetOnce`
rust: str: add radix prefixed integer parsing functions
rust: introduce module_param module
rust: module: use a reference in macros::module::module
rust: module: update the module macro with module parameter support
rust: samples: add a module parameter to the rust_minimal sample
modules: add rust modules files to MAINTAINERS
MAINTAINERS | 2 +
rust/kernel/lib.rs | 1 +
rust/kernel/module_param.rs | 181 ++++++++++++++++++++++++++++++++++++++++
rust/kernel/str.rs | 2 +
rust/kernel/str/parse_int.rs | 148 +++++++++++++++++++++++++++++++++
rust/kernel/sync.rs | 2 +
rust/kernel/sync/set_once.rs | 125 ++++++++++++++++++++++++++++
rust/macros/helpers.rs | 25 ++++++
rust/macros/lib.rs | 31 +++++++
rust/macros/module.rs | 194 +++++++++++++++++++++++++++++++++++++++----
samples/rust/rust_minimal.rs | 10 +++
11 files changed, 703 insertions(+), 18 deletions(-)
---
base-commit: 103265a1a936cfe910c9ac0f0ab153f7dac818ba
change-id: 20241211-module-params-v3-ae7e5c8d8b5a
Best regards,
--
Andreas Hindborg <a.hindborg@kernel.org>
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v18 1/7] rust: sync: add `SetOnce`
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 2/7] rust: str: add radix prefixed integer parsing functions Andreas Hindborg
` (7 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
Introduce the `SetOnce` type, a container that can only be written once.
The container uses an internal atomic to synchronize writes to the internal
value.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
rust/kernel/sync.rs | 2 +
rust/kernel/sync/set_once.rs | 125 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 127 insertions(+)
diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
index cf5b638a097d9..3f957ad3a9f0a 100644
--- a/rust/kernel/sync.rs
+++ b/rust/kernel/sync.rs
@@ -20,6 +20,7 @@
pub mod poll;
pub mod rcu;
mod refcount;
+mod set_once;
pub use arc::{Arc, ArcBorrow, UniqueArc};
pub use completion::Completion;
@@ -29,6 +30,7 @@
pub use lock::spinlock::{new_spinlock, SpinLock, SpinLockGuard};
pub use locked_by::LockedBy;
pub use refcount::Refcount;
+pub use set_once::SetOnce;
/// Represents a lockdep class. It's a wrapper around C's `lock_class_key`.
#[repr(transparent)]
diff --git a/rust/kernel/sync/set_once.rs b/rust/kernel/sync/set_once.rs
new file mode 100644
index 0000000000000..bdba601807d8b
--- /dev/null
+++ b/rust/kernel/sync/set_once.rs
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! A container that can be initialized at most once.
+
+use super::atomic::{
+ ordering::{Acquire, Relaxed, Release},
+ Atomic,
+};
+use core::{cell::UnsafeCell, mem::MaybeUninit};
+
+/// A container that can be populated at most once. Thread safe.
+///
+/// Once the a [`SetOnce`] is populated, it remains populated by the same object for the
+/// lifetime `Self`.
+///
+/// # Invariants
+///
+/// - `init` may only increase in value.
+/// - `init` may only assume values in the range `0..=2`.
+/// - `init == 0` if and only if `value` is uninitialized.
+/// - `init == 1` if and only if there is exactly one thread with exclusive
+/// access to `self.value`.
+/// - `init == 2` if and only if `value` is initialized and valid for shared
+/// access.
+///
+/// # Example
+///
+/// ```
+/// # use kernel::sync::SetOnce;
+/// let value = SetOnce::new();
+/// assert_eq!(None, value.as_ref());
+///
+/// let status = value.populate(42u8);
+/// assert_eq!(true, status);
+/// assert_eq!(Some(&42u8), value.as_ref());
+/// assert_eq!(Some(42u8), value.copy());
+///
+/// let status = value.populate(101u8);
+/// assert_eq!(false, status);
+/// assert_eq!(Some(&42u8), value.as_ref());
+/// assert_eq!(Some(42u8), value.copy());
+/// ```
+pub struct SetOnce<T> {
+ init: Atomic<u32>,
+ value: UnsafeCell<MaybeUninit<T>>,
+}
+
+impl<T> Default for SetOnce<T> {
+ fn default() -> Self {
+ Self::new()
+ }
+}
+
+impl<T> SetOnce<T> {
+ /// Create a new [`SetOnce`].
+ ///
+ /// The returned instance will be empty.
+ pub const fn new() -> Self {
+ // INVARIANT: The container is empty and we initialize `init` to `0`.
+ Self {
+ value: UnsafeCell::new(MaybeUninit::uninit()),
+ init: Atomic::new(0),
+ }
+ }
+
+ /// Get a reference to the contained object.
+ ///
+ /// Returns [`None`] if this [`SetOnce`] is empty.
+ pub fn as_ref(&self) -> Option<&T> {
+ if self.init.load(Acquire) == 2 {
+ // SAFETY: By the type invariants of `Self`, `self.init == 2` means that `self.value`
+ // is initialized and valid for shared access.
+ Some(unsafe { &*self.value.get().cast() })
+ } else {
+ None
+ }
+ }
+
+ /// Populate the [`SetOnce`].
+ ///
+ /// Returns `true` if the [`SetOnce`] was successfully populated.
+ pub fn populate(&self, value: T) -> bool {
+ // INVARIANT: If the swap succeeds:
+ // - We increase `init`.
+ // - We write the valid value `1` to `init`.
+ // - Only one thread can succeed in this write, so we have exclusive access after the
+ // write.
+ if let Ok(0) = self.init.cmpxchg(0, 1, Relaxed) {
+ // SAFETY: By the type invariants of `Self`, the fact that we succeeded in writing `1`
+ // to `self.init` means we obtained exclusive access to `self.value`.
+ unsafe { core::ptr::write(self.value.get().cast(), value) };
+ // INVARIANT:
+ // - We increase `init`.
+ // - We write the valid value `2` to `init`.
+ // - We release our exclusive access to `self.value` and it is now valid for shared
+ // access.
+ self.init.store(2, Release);
+ true
+ } else {
+ false
+ }
+ }
+
+ /// Get a copy of the contained object.
+ ///
+ /// Returns [`None`] if the [`SetOnce`] is empty.
+ pub fn copy(&self) -> Option<T>
+ where
+ T: Copy,
+ {
+ self.as_ref().copied()
+ }
+}
+
+impl<T> Drop for SetOnce<T> {
+ fn drop(&mut self) {
+ if *self.init.get_mut() == 2 {
+ let value = self.value.get_mut();
+ // SAFETY: By the type invariants of `Self`, `self.init == 2` means that `self.value`
+ // contains a valid value. We have exclusive access, as we hold a `mut` reference to
+ // `self`.
+ unsafe { value.assume_init_drop() };
+ }
+ }
+}
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v18 2/7] rust: str: add radix prefixed integer parsing functions
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 1/7] rust: sync: add `SetOnce` Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 3/7] rust: introduce module_param module Andreas Hindborg
` (6 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
Add the trait `ParseInt` for parsing string representations of integers
where the string representations are optionally prefixed by a radix
specifier. Implement the trait for the primitive integer types.
Suggested-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Daniel Gomez <da.gomez@samsung.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
rust/kernel/str.rs | 2 +
rust/kernel/str/parse_int.rs | 148 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 150 insertions(+)
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 6c892550c0ba9..23fe924070e7c 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -8,6 +8,8 @@
use crate::prelude::*;
+pub mod parse_int;
+
/// Byte string without UTF-8 validity guarantee.
#[repr(transparent)]
pub struct BStr([u8]);
diff --git a/rust/kernel/str/parse_int.rs b/rust/kernel/str/parse_int.rs
new file mode 100644
index 0000000000000..48eb4c202984c
--- /dev/null
+++ b/rust/kernel/str/parse_int.rs
@@ -0,0 +1,148 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Integer parsing functions.
+//!
+//! Integer parsing functions for parsing signed and unsigned integers
+//! potentially prefixed with `0x`, `0o`, or `0b`.
+
+use crate::prelude::*;
+use crate::str::BStr;
+use core::ops::Deref;
+
+// Make `FromStrRadix` a public type with a private name. This seals
+// `ParseInt`, that is, prevents downstream users from implementing the
+// trait.
+mod private {
+ use crate::prelude::*;
+ use crate::str::BStr;
+
+ /// Trait that allows parsing a [`&BStr`] to an integer with a radix.
+ pub trait FromStrRadix: Sized {
+ /// Parse `src` to [`Self`] using radix `radix`.
+ fn from_str_radix(src: &BStr, radix: u32) -> Result<Self>;
+
+ /// Tries to convert `value` into [`Self`] and negates the resulting value.
+ fn from_u64_negated(value: u64) -> Result<Self>;
+ }
+}
+
+/// Extract the radix from an integer literal optionally prefixed with
+/// one of `0x`, `0X`, `0o`, `0O`, `0b`, `0B`, `0`.
+fn strip_radix(src: &BStr) -> (u32, &BStr) {
+ match src.deref() {
+ [b'0', b'x' | b'X', rest @ ..] => (16, rest.as_ref()),
+ [b'0', b'o' | b'O', rest @ ..] => (8, rest.as_ref()),
+ [b'0', b'b' | b'B', rest @ ..] => (2, rest.as_ref()),
+ // NOTE: We are including the leading zero to be able to parse
+ // literal `0` here. If we removed it as a radix prefix, we would
+ // not be able to parse `0`.
+ [b'0', ..] => (8, src),
+ _ => (10, src),
+ }
+}
+
+/// Trait for parsing string representations of integers.
+///
+/// Strings beginning with `0x`, `0o`, or `0b` are parsed as hex, octal, or
+/// binary respectively. Strings beginning with `0` otherwise are parsed as
+/// octal. Anything else is parsed as decimal. A leading `+` or `-` is also
+/// permitted. Any string parsed by [`kstrtol()`] or [`kstrtoul()`] will be
+/// successfully parsed.
+///
+/// [`kstrtol()`]: https://docs.kernel.org/core-api/kernel-api.html#c.kstrtol
+/// [`kstrtoul()`]: https://docs.kernel.org/core-api/kernel-api.html#c.kstrtoul
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::str::parse_int::ParseInt;
+/// # use kernel::b_str;
+///
+/// assert_eq!(Ok(0u8), u8::from_str(b_str!("0")));
+///
+/// assert_eq!(Ok(0xa2u8), u8::from_str(b_str!("0xa2")));
+/// assert_eq!(Ok(-0xa2i32), i32::from_str(b_str!("-0xa2")));
+///
+/// assert_eq!(Ok(-0o57i8), i8::from_str(b_str!("-0o57")));
+/// assert_eq!(Ok(0o57i8), i8::from_str(b_str!("057")));
+///
+/// assert_eq!(Ok(0b1001i16), i16::from_str(b_str!("0b1001")));
+/// assert_eq!(Ok(-0b1001i16), i16::from_str(b_str!("-0b1001")));
+///
+/// assert_eq!(Ok(127i8), i8::from_str(b_str!("127")));
+/// assert!(i8::from_str(b_str!("128")).is_err());
+/// assert_eq!(Ok(-128i8), i8::from_str(b_str!("-128")));
+/// assert!(i8::from_str(b_str!("-129")).is_err());
+/// assert_eq!(Ok(255u8), u8::from_str(b_str!("255")));
+/// assert!(u8::from_str(b_str!("256")).is_err());
+/// ```
+pub trait ParseInt: private::FromStrRadix + TryFrom<u64> {
+ /// Parse a string according to the description in [`Self`].
+ fn from_str(src: &BStr) -> Result<Self> {
+ match src.deref() {
+ [b'-', rest @ ..] => {
+ let (radix, digits) = strip_radix(rest.as_ref());
+ // 2's complement values range from -2^(b-1) to 2^(b-1)-1.
+ // So if we want to parse negative numbers as positive and
+ // later multiply by -1, we have to parse into a larger
+ // integer. We choose `u64` as sufficiently large.
+ //
+ // NOTE: 128 bit integers are not available on all
+ // platforms, hence the choice of 64 bits.
+ let val =
+ u64::from_str_radix(core::str::from_utf8(digits).map_err(|_| EINVAL)?, radix)
+ .map_err(|_| EINVAL)?;
+ Self::from_u64_negated(val)
+ }
+ _ => {
+ let (radix, digits) = strip_radix(src);
+ Self::from_str_radix(digits, radix).map_err(|_| EINVAL)
+ }
+ }
+ }
+}
+
+macro_rules! impl_parse_int {
+ ($($ty:ty),*) => {
+ $(
+ impl private::FromStrRadix for $ty {
+ fn from_str_radix(src: &BStr, radix: u32) -> Result<Self> {
+ <$ty>::from_str_radix(core::str::from_utf8(src).map_err(|_| EINVAL)?, radix)
+ .map_err(|_| EINVAL)
+ }
+
+ fn from_u64_negated(value: u64) -> Result<Self> {
+ const ABS_MIN: u64 = {
+ #[allow(unused_comparisons)]
+ if <$ty>::MIN < 0 {
+ 1u64 << (<$ty>::BITS - 1)
+ } else {
+ 0
+ }
+ };
+
+ if value > ABS_MIN {
+ return Err(EINVAL);
+ }
+
+ if value == ABS_MIN {
+ return Ok(<$ty>::MIN);
+ }
+
+ // SAFETY: The above checks guarantee that `value` fits into `Self`:
+ // - if `Self` is unsigned, then `ABS_MIN == 0` and thus we have returned above
+ // (either `EINVAL` or `MIN`).
+ // - if `Self` is signed, then we have that `0 <= value < ABS_MIN`. And since
+ // `ABS_MIN - 1` fits into `Self` by construction, `value` also does.
+ let value: Self = unsafe { value.try_into().unwrap_unchecked() };
+
+ Ok((!value).wrapping_add(1))
+ }
+ }
+
+ impl ParseInt for $ty {}
+ )*
+ };
+}
+
+impl_parse_int![i8, u8, i16, u16, i32, u32, i64, u64, isize, usize];
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v18 3/7] rust: introduce module_param module
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 1/7] rust: sync: add `SetOnce` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 2/7] rust: str: add radix prefixed integer parsing functions Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 4/7] rust: module: use a reference in macros::module::module Andreas Hindborg
` (5 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
Add types and traits for interfacing the C moduleparam API.
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
rust/kernel/lib.rs | 1 +
rust/kernel/module_param.rs | 181 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 182 insertions(+)
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index fef97f2a50984..e34b377d93b2e 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -98,6 +98,7 @@
pub mod list;
pub mod miscdevice;
pub mod mm;
+pub mod module_param;
#[cfg(CONFIG_NET)]
pub mod net;
pub mod of;
diff --git a/rust/kernel/module_param.rs b/rust/kernel/module_param.rs
new file mode 100644
index 0000000000000..e7d5c930a467d
--- /dev/null
+++ b/rust/kernel/module_param.rs
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Support for module parameters.
+//!
+//! C header: [`include/linux/moduleparam.h`](srctree/include/linux/moduleparam.h)
+
+use crate::prelude::*;
+use crate::str::BStr;
+use bindings;
+use kernel::sync::SetOnce;
+
+/// Newtype to make `bindings::kernel_param` [`Sync`].
+#[repr(transparent)]
+#[doc(hidden)]
+pub struct KernelParam(bindings::kernel_param);
+
+impl KernelParam {
+ #[doc(hidden)]
+ pub const fn new(val: bindings::kernel_param) -> Self {
+ Self(val)
+ }
+}
+
+// SAFETY: C kernel handles serializing access to this type. We never access it
+// from Rust module.
+unsafe impl Sync for KernelParam {}
+
+/// Types that can be used for module parameters.
+// NOTE: This trait is `Copy` because drop could produce unsoundness during teardown.
+pub trait ModuleParam: Sized + Copy {
+ /// Parse a parameter argument into the parameter value.
+ fn try_from_param_arg(arg: &BStr) -> Result<Self>;
+}
+
+/// Set the module parameter from a string.
+///
+/// Used to set the parameter value at kernel initialization, when loading
+/// the module or when set through `sysfs`.
+///
+/// See `struct kernel_param_ops.set`.
+///
+/// # Safety
+///
+/// - If `val` is non-null then it must point to a valid null-terminated string that must be valid
+/// for reads for the duration of the call.
+/// - `param` must be a pointer to a `bindings::kernel_param` initialized by the rust module macro.
+/// The pointee must be valid for reads for the duration of the call.
+///
+/// # Note
+///
+/// - The safety requirements are satisfied by C API contract when this function is invoked by the
+/// module subsystem C code.
+/// - Currently, we only support read-only parameters that are not readable from `sysfs`. Thus, this
+/// function is only called at kernel initialization time, or at module load time, and we have
+/// exclusive access to the parameter for the duration of the function.
+///
+/// [`module!`]: macros::module
+unsafe extern "C" fn set_param<T>(val: *const c_char, param: *const bindings::kernel_param) -> c_int
+where
+ T: ModuleParam,
+{
+ // NOTE: If we start supporting arguments without values, val _is_ allowed
+ // to be null here.
+ if val.is_null() {
+ // TODO: Use pr_warn_once available.
+ crate::pr_warn!("Null pointer passed to `module_param::set_param`");
+ return EINVAL.to_errno();
+ }
+
+ // SAFETY: By function safety requirement, val is non-null, null-terminated
+ // and valid for reads for the duration of this function.
+ let arg = unsafe { CStr::from_char_ptr(val) };
+
+ crate::error::from_result(|| {
+ let new_value = T::try_from_param_arg(arg)?;
+
+ // SAFETY: By function safety requirements, this access is safe.
+ let container = unsafe { &*((*param).__bindgen_anon_1.arg.cast::<SetOnce<T>>()) };
+
+ container
+ .populate(new_value)
+ .then_some(0)
+ .ok_or(kernel::error::code::EEXIST)
+ })
+}
+
+macro_rules! impl_int_module_param {
+ ($ty:ident) => {
+ impl ModuleParam for $ty {
+ fn try_from_param_arg(arg: &BStr) -> Result<Self> {
+ <$ty as crate::str::parse_int::ParseInt>::from_str(arg)
+ }
+ }
+ };
+}
+
+impl_int_module_param!(i8);
+impl_int_module_param!(u8);
+impl_int_module_param!(i16);
+impl_int_module_param!(u16);
+impl_int_module_param!(i32);
+impl_int_module_param!(u32);
+impl_int_module_param!(i64);
+impl_int_module_param!(u64);
+impl_int_module_param!(isize);
+impl_int_module_param!(usize);
+
+/// A wrapper for kernel parameters.
+///
+/// This type is instantiated by the [`module!`] macro when module parameters are
+/// defined. You should never need to instantiate this type directly.
+///
+/// Note: This type is `pub` because it is used by module crates to access
+/// parameter values.
+pub struct ModuleParamAccess<T> {
+ value: SetOnce<T>,
+ default: T,
+}
+
+// SAFETY: We only create shared references to the contents of this container,
+// so if `T` is `Sync`, so is `ModuleParamAccess`.
+unsafe impl<T: Sync> Sync for ModuleParamAccess<T> {}
+
+impl<T> ModuleParamAccess<T> {
+ #[doc(hidden)]
+ pub const fn new(default: T) -> Self {
+ Self {
+ value: SetOnce::new(),
+ default,
+ }
+ }
+
+ /// Get a shared reference to the parameter value.
+ // Note: When sysfs access to parameters are enabled, we have to pass in a
+ // held lock guard here.
+ pub fn value(&self) -> &T {
+ self.value.as_ref().unwrap_or(&self.default)
+ }
+
+ /// Get a mutable pointer to `self`.
+ ///
+ /// NOTE: In most cases it is not safe deref the returned pointer.
+ pub const fn as_void_ptr(&self) -> *mut c_void {
+ core::ptr::from_ref(self).cast_mut().cast()
+ }
+}
+
+#[doc(hidden)]
+/// Generate a static [`kernel_param_ops`](srctree/include/linux/moduleparam.h) struct.
+///
+/// # Examples
+///
+/// ```ignore
+/// make_param_ops!(
+/// /// Documentation for new param ops.
+/// PARAM_OPS_MYTYPE, // Name for the static.
+/// MyType // A type which implements [`ModuleParam`].
+/// );
+/// ```
+macro_rules! make_param_ops {
+ ($ops:ident, $ty:ty) => {
+ #[doc(hidden)]
+ pub static $ops: $crate::bindings::kernel_param_ops = $crate::bindings::kernel_param_ops {
+ flags: 0,
+ set: Some(set_param::<$ty>),
+ get: None,
+ free: None,
+ };
+ };
+}
+
+make_param_ops!(PARAM_OPS_I8, i8);
+make_param_ops!(PARAM_OPS_U8, u8);
+make_param_ops!(PARAM_OPS_I16, i16);
+make_param_ops!(PARAM_OPS_U16, u16);
+make_param_ops!(PARAM_OPS_I32, i32);
+make_param_ops!(PARAM_OPS_U32, u32);
+make_param_ops!(PARAM_OPS_I64, i64);
+make_param_ops!(PARAM_OPS_U64, u64);
+make_param_ops!(PARAM_OPS_ISIZE, isize);
+make_param_ops!(PARAM_OPS_USIZE, usize);
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v18 4/7] rust: module: use a reference in macros::module::module
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
` (2 preceding siblings ...)
2025-09-24 12:39 ` [PATCH v18 3/7] rust: introduce module_param module Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 5/7] rust: module: update the module macro with module parameter support Andreas Hindborg
` (4 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
When we add parameter support to the module macro, we want to be able to
pass a reference to `ModuleInfo` to a helper function. That is not possible
when we move out of the local `modinfo`. So change the function to access
the local via reference rather than value.
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
rust/macros/module.rs | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index 5ee54a00c0b65..cbf3ac0a8f7ba 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -176,23 +176,23 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
// Rust does not allow hyphens in identifiers, use underscore instead.
let ident = info.name.replace('-', "_");
let mut modinfo = ModInfoBuilder::new(ident.as_ref());
- if let Some(authors) = info.authors {
+ if let Some(authors) = &info.authors {
for author in authors {
- modinfo.emit("author", &author);
+ modinfo.emit("author", author);
}
}
- if let Some(description) = info.description {
- modinfo.emit("description", &description);
+ if let Some(description) = &info.description {
+ modinfo.emit("description", description);
}
modinfo.emit("license", &info.license);
- if let Some(aliases) = info.alias {
+ if let Some(aliases) = &info.alias {
for alias in aliases {
- modinfo.emit("alias", &alias);
+ modinfo.emit("alias", alias);
}
}
- if let Some(firmware) = info.firmware {
+ if let Some(firmware) = &info.firmware {
for fw in firmware {
- modinfo.emit("firmware", &fw);
+ modinfo.emit("firmware", fw);
}
}
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v18 5/7] rust: module: update the module macro with module parameter support
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
` (3 preceding siblings ...)
2025-09-24 12:39 ` [PATCH v18 4/7] rust: module: use a reference in macros::module::module Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 6/7] rust: samples: add a module parameter to the rust_minimal sample Andreas Hindborg
` (3 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
Allow module parameters to be declared in the rust `module!` macro.
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
rust/macros/helpers.rs | 25 +++++++
rust/macros/lib.rs | 31 +++++++++
rust/macros/module.rs | 178 ++++++++++++++++++++++++++++++++++++++++++++++---
3 files changed, 224 insertions(+), 10 deletions(-)
diff --git a/rust/macros/helpers.rs b/rust/macros/helpers.rs
index e2602be402c10..365d7eb499c08 100644
--- a/rust/macros/helpers.rs
+++ b/rust/macros/helpers.rs
@@ -10,6 +10,17 @@ pub(crate) fn try_ident(it: &mut token_stream::IntoIter) -> Option<String> {
}
}
+pub(crate) fn try_sign(it: &mut token_stream::IntoIter) -> Option<char> {
+ let peek = it.clone().next();
+ match peek {
+ Some(TokenTree::Punct(punct)) if punct.as_char() == '-' => {
+ let _ = it.next();
+ Some(punct.as_char())
+ }
+ _ => None,
+ }
+}
+
pub(crate) fn try_literal(it: &mut token_stream::IntoIter) -> Option<String> {
if let Some(TokenTree::Literal(literal)) = it.next() {
Some(literal.to_string())
@@ -103,3 +114,17 @@ pub(crate) fn file() -> String {
proc_macro::Span::call_site().file()
}
}
+
+/// Parse a token stream of the form `expected_name: "value",` and return the
+/// string in the position of "value".
+///
+/// # Panics
+///
+/// - On parse error.
+pub(crate) fn expect_string_field(it: &mut token_stream::IntoIter, expected_name: &str) -> String {
+ assert_eq!(expect_ident(it), expected_name);
+ assert_eq!(expect_punct(it), ':');
+ let string = expect_string(it);
+ assert_eq!(expect_punct(it), ',');
+ string
+}
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index fa847cf3a9b5f..2fb520dc930af 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -28,6 +28,30 @@
/// The `type` argument should be a type which implements the [`Module`]
/// trait. Also accepts various forms of kernel metadata.
///
+/// The `params` field describe module parameters. Each entry has the form
+///
+/// ```ignore
+/// parameter_name: type {
+/// default: default_value,
+/// description: "Description",
+/// }
+/// ```
+///
+/// `type` may be one of
+///
+/// - [`i8`]
+/// - [`u8`]
+/// - [`i8`]
+/// - [`u8`]
+/// - [`i16`]
+/// - [`u16`]
+/// - [`i32`]
+/// - [`u32`]
+/// - [`i64`]
+/// - [`u64`]
+/// - [`isize`]
+/// - [`usize`]
+///
/// C header: [`include/linux/moduleparam.h`](srctree/include/linux/moduleparam.h)
///
/// [`Module`]: ../kernel/trait.Module.html
@@ -44,6 +68,12 @@
/// description: "My very own kernel module!",
/// license: "GPL",
/// alias: ["alternate_module_name"],
+/// params: {
+/// my_parameter: i64 {
+/// default: 1,
+/// description: "This parameter has a default of 1",
+/// },
+/// },
/// }
///
/// struct MyModule(i32);
@@ -52,6 +82,7 @@
/// fn init(_module: &'static ThisModule) -> Result<Self> {
/// let foo: i32 = 42;
/// pr_info!("I contain: {}\n", foo);
+/// pr_info!("i32 param is: {}\n", module_parameters::my_parameter.read());
/// Ok(Self(foo))
/// }
/// }
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index cbf3ac0a8f7ba..d62e9c1e2a898 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -26,6 +26,7 @@ struct ModInfoBuilder<'a> {
module: &'a str,
counter: usize,
buffer: String,
+ param_buffer: String,
}
impl<'a> ModInfoBuilder<'a> {
@@ -34,10 +35,11 @@ fn new(module: &'a str) -> Self {
module,
counter: 0,
buffer: String::new(),
+ param_buffer: String::new(),
}
}
- fn emit_base(&mut self, field: &str, content: &str, builtin: bool) {
+ fn emit_base(&mut self, field: &str, content: &str, builtin: bool, param: bool) {
let string = if builtin {
// Built-in modules prefix their modinfo strings by `module.`.
format!(
@@ -51,8 +53,14 @@ fn emit_base(&mut self, field: &str, content: &str, builtin: bool) {
format!("{field}={content}\0")
};
+ let buffer = if param {
+ &mut self.param_buffer
+ } else {
+ &mut self.buffer
+ };
+
write!(
- &mut self.buffer,
+ buffer,
"
{cfg}
#[doc(hidden)]
@@ -75,20 +83,119 @@ fn emit_base(&mut self, field: &str, content: &str, builtin: bool) {
self.counter += 1;
}
- fn emit_only_builtin(&mut self, field: &str, content: &str) {
- self.emit_base(field, content, true)
+ fn emit_only_builtin(&mut self, field: &str, content: &str, param: bool) {
+ self.emit_base(field, content, true, param)
}
- fn emit_only_loadable(&mut self, field: &str, content: &str) {
- self.emit_base(field, content, false)
+ fn emit_only_loadable(&mut self, field: &str, content: &str, param: bool) {
+ self.emit_base(field, content, false, param)
}
fn emit(&mut self, field: &str, content: &str) {
- self.emit_only_builtin(field, content);
- self.emit_only_loadable(field, content);
+ self.emit_internal(field, content, false);
+ }
+
+ fn emit_internal(&mut self, field: &str, content: &str, param: bool) {
+ self.emit_only_builtin(field, content, param);
+ self.emit_only_loadable(field, content, param);
+ }
+
+ fn emit_param(&mut self, field: &str, param: &str, content: &str) {
+ let content = format!("{param}:{content}", param = param, content = content);
+ self.emit_internal(field, &content, true);
+ }
+
+ fn emit_params(&mut self, info: &ModuleInfo) {
+ let Some(params) = &info.params else {
+ return;
+ };
+
+ for param in params {
+ let ops = param_ops_path(¶m.ptype);
+
+ // Note: The spelling of these fields is dictated by the user space
+ // tool `modinfo`.
+ self.emit_param("parmtype", ¶m.name, ¶m.ptype);
+ self.emit_param("parm", ¶m.name, ¶m.description);
+
+ write!(
+ self.param_buffer,
+ "
+ pub(crate) static {param_name}:
+ ::kernel::module_param::ModuleParamAccess<{param_type}> =
+ ::kernel::module_param::ModuleParamAccess::new({param_default});
+
+ const _: () = {{
+ #[link_section = \"__param\"]
+ #[used]
+ static __{module_name}_{param_name}_struct:
+ ::kernel::module_param::KernelParam =
+ ::kernel::module_param::KernelParam::new(
+ ::kernel::bindings::kernel_param {{
+ name: if ::core::cfg!(MODULE) {{
+ ::kernel::c_str!(\"{param_name}\").as_bytes_with_nul()
+ }} else {{
+ ::kernel::c_str!(\"{module_name}.{param_name}\")
+ .as_bytes_with_nul()
+ }}.as_ptr(),
+ // SAFETY: `__this_module` is constructed by the kernel at load
+ // time and will not be freed until the module is unloaded.
+ #[cfg(MODULE)]
+ mod_: unsafe {{
+ core::ptr::from_ref(&::kernel::bindings::__this_module)
+ .cast_mut()
+ }},
+ #[cfg(not(MODULE))]
+ mod_: ::core::ptr::null_mut(),
+ ops: core::ptr::from_ref(&{ops}),
+ perm: 0, // Will not appear in sysfs
+ level: -1,
+ flags: 0,
+ __bindgen_anon_1: ::kernel::bindings::kernel_param__bindgen_ty_1 {{
+ arg: {param_name}.as_void_ptr()
+ }},
+ }}
+ );
+ }};
+ ",
+ module_name = info.name,
+ param_type = param.ptype,
+ param_default = param.default,
+ param_name = param.name,
+ ops = ops,
+ )
+ .unwrap();
+ }
+ }
+}
+
+fn param_ops_path(param_type: &str) -> &'static str {
+ match param_type {
+ "i8" => "::kernel::module_param::PARAM_OPS_I8",
+ "u8" => "::kernel::module_param::PARAM_OPS_U8",
+ "i16" => "::kernel::module_param::PARAM_OPS_I16",
+ "u16" => "::kernel::module_param::PARAM_OPS_U16",
+ "i32" => "::kernel::module_param::PARAM_OPS_I32",
+ "u32" => "::kernel::module_param::PARAM_OPS_U32",
+ "i64" => "::kernel::module_param::PARAM_OPS_I64",
+ "u64" => "::kernel::module_param::PARAM_OPS_U64",
+ "isize" => "::kernel::module_param::PARAM_OPS_ISIZE",
+ "usize" => "::kernel::module_param::PARAM_OPS_USIZE",
+ t => panic!("Unsupported parameter type {}", t),
}
}
+fn expect_param_default(param_it: &mut token_stream::IntoIter) -> String {
+ assert_eq!(expect_ident(param_it), "default");
+ assert_eq!(expect_punct(param_it), ':');
+ let sign = try_sign(param_it);
+ let default = try_literal(param_it).expect("Expected default param value");
+ assert_eq!(expect_punct(param_it), ',');
+ let mut value = sign.map(String::from).unwrap_or_default();
+ value.push_str(&default);
+ value
+}
+
#[derive(Debug, Default)]
struct ModuleInfo {
type_: String,
@@ -98,6 +205,50 @@ struct ModuleInfo {
description: Option<String>,
alias: Option<Vec<String>>,
firmware: Option<Vec<String>>,
+ params: Option<Vec<Parameter>>,
+}
+
+#[derive(Debug)]
+struct Parameter {
+ name: String,
+ ptype: String,
+ default: String,
+ description: String,
+}
+
+fn expect_params(it: &mut token_stream::IntoIter) -> Vec<Parameter> {
+ let params = expect_group(it);
+ assert_eq!(params.delimiter(), Delimiter::Brace);
+ let mut it = params.stream().into_iter();
+ let mut parsed = Vec::new();
+
+ loop {
+ let param_name = match it.next() {
+ Some(TokenTree::Ident(ident)) => ident.to_string(),
+ Some(_) => panic!("Expected Ident or end"),
+ None => break,
+ };
+
+ assert_eq!(expect_punct(&mut it), ':');
+ let param_type = expect_ident(&mut it);
+ let group = expect_group(&mut it);
+ assert_eq!(group.delimiter(), Delimiter::Brace);
+ assert_eq!(expect_punct(&mut it), ',');
+
+ let mut param_it = group.stream().into_iter();
+ let param_default = expect_param_default(&mut param_it);
+ let param_description = expect_string_field(&mut param_it, "description");
+ expect_end(&mut param_it);
+
+ parsed.push(Parameter {
+ name: param_name,
+ ptype: param_type,
+ default: param_default,
+ description: param_description,
+ })
+ }
+
+ parsed
}
impl ModuleInfo {
@@ -112,6 +263,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
"license",
"alias",
"firmware",
+ "params",
];
const REQUIRED_KEYS: &[&str] = &["type", "name", "license"];
let mut seen_keys = Vec::new();
@@ -137,6 +289,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
"license" => info.license = expect_string_ascii(it),
"alias" => info.alias = Some(expect_string_array(it)),
"firmware" => info.firmware = Some(expect_string_array(it)),
+ "params" => info.params = Some(expect_params(it)),
_ => panic!("Unknown key \"{key}\". Valid keys are: {EXPECTED_KEYS:?}."),
}
@@ -199,7 +352,9 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
// Built-in modules also export the `file` modinfo string.
let file =
std::env::var("RUST_MODFILE").expect("Unable to fetch RUST_MODFILE environmental variable");
- modinfo.emit_only_builtin("file", &file);
+ modinfo.emit_only_builtin("file", &file, false);
+
+ modinfo.emit_params(&info);
format!(
"
@@ -363,15 +518,18 @@ unsafe fn __exit() {{
__MOD.assume_init_drop();
}}
}}
-
{modinfo}
}}
}}
+ mod module_parameters {{
+ {params}
+ }}
",
type_ = info.type_,
name = info.name,
ident = ident,
modinfo = modinfo.buffer,
+ params = modinfo.param_buffer,
initcall_section = ".initcall6.init"
)
.parse()
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v18 6/7] rust: samples: add a module parameter to the rust_minimal sample
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
` (4 preceding siblings ...)
2025-09-24 12:39 ` [PATCH v18 5/7] rust: module: update the module macro with module parameter support Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 7/7] modules: add rust modules files to MAINTAINERS Andreas Hindborg
` (2 subsequent siblings)
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
Showcase the rust module parameter support by adding a module parameter to
the `rust_minimal` sample.
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
samples/rust/rust_minimal.rs | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/samples/rust/rust_minimal.rs b/samples/rust/rust_minimal.rs
index 1fc7a1be6b6d7..8eb9583571d72 100644
--- a/samples/rust/rust_minimal.rs
+++ b/samples/rust/rust_minimal.rs
@@ -10,6 +10,12 @@
authors: ["Rust for Linux Contributors"],
description: "Rust minimal sample",
license: "GPL",
+ params: {
+ test_parameter: i64 {
+ default: 1,
+ description: "This parameter has a default of 1",
+ },
+ },
}
struct RustMinimal {
@@ -20,6 +26,10 @@ impl kernel::Module for RustMinimal {
fn init(_module: &'static ThisModule) -> Result<Self> {
pr_info!("Rust minimal sample (init)\n");
pr_info!("Am I built-in? {}\n", !cfg!(MODULE));
+ pr_info!(
+ "test_parameter: {}\n",
+ *module_parameters::test_parameter.value()
+ );
let mut numbers = KVec::new();
numbers.push(72, GFP_KERNEL)?;
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v18 7/7] modules: add rust modules files to MAINTAINERS
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
` (5 preceding siblings ...)
2025-09-24 12:39 ` [PATCH v18 6/7] rust: samples: add a module parameter to the rust_minimal sample Andreas Hindborg
@ 2025-09-24 12:39 ` Andreas Hindborg
2025-11-01 21:39 ` [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Daniel Gomez
2025-11-03 14:47 ` Daniel Gomez
8 siblings, 0 replies; 12+ messages in thread
From: Andreas Hindborg @ 2025-09-24 12:39 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Daniel Gomez, Benno Lossin, Nicolas Schier
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules, Andreas Hindborg
The module subsystem people agreed to maintain rust support for modules
[1]. Thus, add entries for relevant files to modules entry in MAINTAINERS.
Link: https://lore.kernel.org/all/0d9e596a-5316-4e00-862b-fd77552ae4b5@suse.com/ [1]
Acked-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
MAINTAINERS | 2 ++
1 file changed, 2 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index d69021b88aef0..55e3bf16ea0a8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17136,6 +17136,8 @@ F: include/linux/module*.h
F: kernel/module/
F: lib/test_kmod.c
F: lib/tests/module/
+F: rust/kernel/module_param.rs
+F: rust/macros/module.rs
F: scripts/module*
F: tools/testing/selftests/kmod/
F: tools/testing/selftests/module/
--
2.47.2
^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
` (6 preceding siblings ...)
2025-09-24 12:39 ` [PATCH v18 7/7] modules: add rust modules files to MAINTAINERS Andreas Hindborg
@ 2025-11-01 21:39 ` Daniel Gomez
2025-11-02 9:56 ` Uwe Kleine-König
2025-11-03 14:47 ` Daniel Gomez
8 siblings, 1 reply; 12+ messages in thread
From: Daniel Gomez @ 2025-11-01 21:39 UTC (permalink / raw)
To: Andreas Hindborg, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Nicolas Schier, Uwe Kleine-König,
Michal Wilczynski
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules
On 24/09/2025 14.39, Andreas Hindborg wrote:
> Extend the `module!` macro with support module parameters. Also add some
> string to integer parsing functions.
>
> Based on the original module parameter support by Miguel [1],
> later extended and generalized by Adam for more types [2][3].
> Originally tracked at [4].
>
> Link: https://github.com/Rust-for-Linux/linux/pull/7 [1]
> Link: https://github.com/Rust-for-Linux/linux/pull/82 [2]
> Link: https://github.com/Rust-for-Linux/linux/pull/87 [3]
> Link: https://github.com/Rust-for-Linux/linux/issues/11 [4]
> Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
I tested this series with rust_minimal module. They LGTM,
Tested-by: Daniel Gomez <da.gomez@samsung.com>
The patches did not apply cleanly to v6.18-rc3, at least not when using b4.
However, when applying them to the base commit and then rebasing onto v6.18-rc3,
I didn't see any conflicts.
I've created a temporary branch with this rebase here:
https://git.kernel.org/pub/scm/linux/kernel/git/modules/linux.git/log/?h=rebase/20250924-module-params-v3-v18-0-bf512c35d910@kernel.org
Can you take a look when you can? I'll merge this shortly after checking with
Uwe, as there are some minor conflicts with his tree.
+ Uwe
These are the conflicts I see when merging the patch series from Michal [1]
(Introduce import_ns support for Rust). I believe these are trivial things that
we will get notified from linux-next merging. But let me know what you think as
you have requested in that thread.
[1] Link: https://lore.kernel.org/all/20251028-pwm_fixes-v1-0-25a532d31998@samsung.com/
...
Applying: rust: macros: Add support for 'imports_ns' to module!
Patch failed at 0008 rust: macros: Add support for 'imports_ns' to module!
error: patch failed: rust/macros/module.rs:98
error: rust/macros/module.rs: patch does not apply
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config set advice.mergeConflict false"
git am --show-current-patch=diff
---
rust/macros/module.rs | 8 ++++++++
1 file changed, 8 insertions(+)
---
rust/macros/module.rs | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index 5ee54a00c0b65699596e660b2d4d60e64be2a50c..408cd115487514c8be79724d901c676435696376 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -98,6 +98,7 @@ struct ModuleInfo {
description: Option<String>,
alias: Option<Vec<String>>,
firmware: Option<Vec<String>>,
+ imports_ns: Option<Vec<String>>,
}
impl ModuleInfo {
@@ -112,6 +113,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
"license",
"alias",
"firmware",
+ "imports_ns",
];
const REQUIRED_KEYS: &[&str] = &["type", "name", "license"];
let mut seen_keys = Vec::new();
@@ -137,6 +139,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
"license" => info.license = expect_string_ascii(it),
"alias" => info.alias = Some(expect_string_array(it)),
"firmware" => info.firmware = Some(expect_string_array(it)),
+ "imports_ns" => info.imports_ns = Some(expect_string_array(it)),
_ => panic!("Unknown key \"{key}\". Valid keys are: {EXPECTED_KEYS:?}."),
}
@@ -195,6 +198,11 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
modinfo.emit("firmware", &fw);
}
}
+ if let Some(imports) = info.imports_ns {
+ for ns in imports {
+ modinfo.emit("import_ns", &ns);
+ }
+ }
// Built-in modules also export the `file` modinfo string.
let file =
^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support
2025-11-01 21:39 ` [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Daniel Gomez
@ 2025-11-02 9:56 ` Uwe Kleine-König
2025-11-02 21:19 ` Daniel Gomez
0 siblings, 1 reply; 12+ messages in thread
From: Uwe Kleine-König @ 2025-11-02 9:56 UTC (permalink / raw)
To: Daniel Gomez
Cc: Andreas Hindborg, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Nicolas Schier, Michal Wilczynski, Trevor Gross,
Adam Bratschi-Kaye, rust-for-linux, linux-kernel, linux-kbuild,
Petr Pavlu, Sami Tolvanen, Daniel Gomez, Simona Vetter, Greg KH,
Fiona Behrens, Daniel Almeida, linux-modules, Stephen Rothwell,
linux-next
[-- Attachment #1: Type: text/plain, Size: 8479 bytes --]
Hello Daniel,
[Adding Stephen and linux-next to Cc]
On Sat, Nov 01, 2025 at 10:39:08PM +0100, Daniel Gomez wrote:
> On 24/09/2025 14.39, Andreas Hindborg wrote:
> > Extend the `module!` macro with support module parameters. Also add some
> > string to integer parsing functions.
> >
> > Based on the original module parameter support by Miguel [1],
> > later extended and generalized by Adam for more types [2][3].
> > Originally tracked at [4].
> >
> > Link: https://github.com/Rust-for-Linux/linux/pull/7 [1]
> > Link: https://github.com/Rust-for-Linux/linux/pull/82 [2]
> > Link: https://github.com/Rust-for-Linux/linux/pull/87 [3]
> > Link: https://github.com/Rust-for-Linux/linux/issues/11 [4]
> > Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
>
> I tested this series with rust_minimal module. They LGTM,
>
> Tested-by: Daniel Gomez <da.gomez@samsung.com>
>
> The patches did not apply cleanly to v6.18-rc3, at least not when using b4.
> However, when applying them to the base commit and then rebasing onto v6.18-rc3,
> I didn't see any conflicts.
I don't know how you use b4, but
git checkout v6.18-rc3
b4 am -3 49af6d76-bcb7-4343-8903-390040e2c49b@kernel.org
git am -3 ./v18_20250924_a_hindborg_rust_extend_module_macro_with_integer_parameter_support.mbx
works fine on my end. Using `-3` should have the same effect as applying
the series on top of the original base and rebase it.
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/modules/linux.git rebase/20250924-module-params-v3-v18-0-bf512c35d910@kernel.org
git range-diff FETCH_HEAD...HEAD
confirms that.
> I've created a temporary branch with this rebase here:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/modules/linux.git/log/?h=rebase/20250924-module-params-v3-v18-0-bf512c35d910@kernel.org
>
> Can you take a look when you can? I'll merge this shortly after checking with
> Uwe, as there are some minor conflicts with his tree.
>
> + Uwe
>
> These are the conflicts I see when merging the patch series from Michal [1]
> (Introduce import_ns support for Rust). I believe these are trivial things that
> we will get notified from linux-next merging. But let me know what you think as
> you have requested in that thread.
>
> [1] Link: https://lore.kernel.org/all/20251028-pwm_fixes-v1-0-25a532d31998@samsung.com/
Yeah, I expect that Stephen will highlight the conflicts, but I prefer
to not be surprised by that and consider linux-next more a fallback
security net that I don't want to use. I like it to be the other way
round and tell Stephen about conflicts to expect :-)
> ...
> Applying: rust: macros: Add support for 'imports_ns' to module!
> Patch failed at 0008 rust: macros: Add support for 'imports_ns' to module!
> error: patch failed: rust/macros/module.rs:98
> error: rust/macros/module.rs: patch does not apply
> hint: Use 'git am --show-current-patch=diff' to see the failed patch
> hint: When you have resolved this problem, run "git am --continue".
> hint: If you prefer to skip this patch, run "git am --skip" instead.
> hint: To restore the original branch and stop patching, run "git am --abort".
> hint: Disable this message with "git config set advice.mergeConflict false"
>
> git am --show-current-patch=diff
That command shows the patch to apply, but not the conflict, let alone
your resolution.
> ---
> rust/macros/module.rs | 8 ++++++++
> 1 file changed, 8 insertions(+)
> ---
> rust/macros/module.rs | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/rust/macros/module.rs b/rust/macros/module.rs
> index 5ee54a00c0b65699596e660b2d4d60e64be2a50c..408cd115487514c8be79724d901c676435696376 100644
> --- a/rust/macros/module.rs
> +++ b/rust/macros/module.rs
> @@ -98,6 +98,7 @@ struct ModuleInfo {
> description: Option<String>,
> alias: Option<Vec<String>>,
> firmware: Option<Vec<String>>,
> + imports_ns: Option<Vec<String>>,
> }
So here the addition of `params` is missing.
> [...]
When I merge your branch mentioned above with my pwm/for-next and
resolve the merge conflicts, the resolution looks as follows. The only
non-trivial thing is that
if let Some(imports) = info.imports_ns {
now needs a & for `info`.
Best regards
Uwe
diff --cc rust/macros/module.rs
index d62e9c1e2a89,408cd1154875..000000000000
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@@ -205,50 -98,7 +205,51 @@@ struct ModuleInfo
description: Option<String>,
alias: Option<Vec<String>>,
firmware: Option<Vec<String>>,
+ imports_ns: Option<Vec<String>>,
+ params: Option<Vec<Parameter>>,
+}
+
+#[derive(Debug)]
+struct Parameter {
+ name: String,
+ ptype: String,
+ default: String,
+ description: String,
+}
+
+fn expect_params(it: &mut token_stream::IntoIter) -> Vec<Parameter> {
+ let params = expect_group(it);
+ assert_eq!(params.delimiter(), Delimiter::Brace);
+ let mut it = params.stream().into_iter();
+ let mut parsed = Vec::new();
+
+ loop {
+ let param_name = match it.next() {
+ Some(TokenTree::Ident(ident)) => ident.to_string(),
+ Some(_) => panic!("Expected Ident or end"),
+ None => break,
+ };
+
+ assert_eq!(expect_punct(&mut it), ':');
+ let param_type = expect_ident(&mut it);
+ let group = expect_group(&mut it);
+ assert_eq!(group.delimiter(), Delimiter::Brace);
+ assert_eq!(expect_punct(&mut it), ',');
+
+ let mut param_it = group.stream().into_iter();
+ let param_default = expect_param_default(&mut param_it);
+ let param_description = expect_string_field(&mut param_it, "description");
+ expect_end(&mut param_it);
+
+ parsed.push(Parameter {
+ name: param_name,
+ ptype: param_type,
+ default: param_default,
+ description: param_description,
+ })
+ }
+
+ parsed
}
impl ModuleInfo {
@@@ -263,7 -113,7 +264,8 @@@
"license",
"alias",
"firmware",
+ "imports_ns",
+ "params",
];
const REQUIRED_KEYS: &[&str] = &["type", "name", "license"];
let mut seen_keys = Vec::new();
@@@ -289,7 -139,7 +291,8 @@@
"license" => info.license = expect_string_ascii(it),
"alias" => info.alias = Some(expect_string_array(it)),
"firmware" => info.firmware = Some(expect_string_array(it)),
+ "imports_ns" => info.imports_ns = Some(expect_string_array(it)),
+ "params" => info.params = Some(expect_params(it)),
_ => panic!("Unknown key \"{key}\". Valid keys are: {EXPECTED_KEYS:?}."),
}
@@@ -329,25 -179,30 +332,30 @@@ pub(crate) fn module(ts: TokenStream) -
// Rust does not allow hyphens in identifiers, use underscore instead.
let ident = info.name.replace('-', "_");
let mut modinfo = ModInfoBuilder::new(ident.as_ref());
- if let Some(authors) = info.authors {
+ if let Some(authors) = &info.authors {
for author in authors {
- modinfo.emit("author", &author);
+ modinfo.emit("author", author);
}
}
- if let Some(description) = info.description {
- modinfo.emit("description", &description);
+ if let Some(description) = &info.description {
+ modinfo.emit("description", description);
}
modinfo.emit("license", &info.license);
- if let Some(aliases) = info.alias {
+ if let Some(aliases) = &info.alias {
for alias in aliases {
- modinfo.emit("alias", &alias);
+ modinfo.emit("alias", alias);
}
}
- if let Some(firmware) = info.firmware {
+ if let Some(firmware) = &info.firmware {
for fw in firmware {
- modinfo.emit("firmware", &fw);
+ modinfo.emit("firmware", fw);
}
}
- if let Some(imports) = info.imports_ns {
++ if let Some(imports) = &info.imports_ns {
+ for ns in imports {
+ modinfo.emit("import_ns", &ns);
+ }
+ }
// Built-in modules also export the `file` modinfo string.
let file =
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support
2025-11-02 9:56 ` Uwe Kleine-König
@ 2025-11-02 21:19 ` Daniel Gomez
0 siblings, 0 replies; 12+ messages in thread
From: Daniel Gomez @ 2025-11-02 21:19 UTC (permalink / raw)
To: Uwe Kleine-König
Cc: Andreas Hindborg, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Nicolas Schier, Michal Wilczynski, Trevor Gross,
Adam Bratschi-Kaye, rust-for-linux, linux-kernel, linux-kbuild,
Petr Pavlu, Sami Tolvanen, Daniel Gomez, Simona Vetter, Greg KH,
Fiona Behrens, Daniel Almeida, linux-modules, Stephen Rothwell,
linux-next
On 02/11/2025 10.56, Uwe Kleine-König wrote:
> Hello Daniel,
>
> [Adding Stephen and linux-next to Cc]
>
> On Sat, Nov 01, 2025 at 10:39:08PM +0100, Daniel Gomez wrote:
>> On 24/09/2025 14.39, Andreas Hindborg wrote:
>>> Extend the `module!` macro with support module parameters. Also add some
>>> string to integer parsing functions.
>>>
>>> Based on the original module parameter support by Miguel [1],
>>> later extended and generalized by Adam for more types [2][3].
>>> Originally tracked at [4].
>>>
>>> Link: https://github.com/Rust-for-Linux/linux/pull/7 [1]
>>> Link: https://github.com/Rust-for-Linux/linux/pull/82 [2]
>>> Link: https://github.com/Rust-for-Linux/linux/pull/87 [3]
>>> Link: https://github.com/Rust-for-Linux/linux/issues/11 [4]
>>> Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
>>
>> I tested this series with rust_minimal module. They LGTM,
>>
>> Tested-by: Daniel Gomez <da.gomez@samsung.com>
>>
>> The patches did not apply cleanly to v6.18-rc3, at least not when using b4.
>> However, when applying them to the base commit and then rebasing onto v6.18-rc3,
>> I didn't see any conflicts.
>
> I don't know how you use b4, but
>
> git checkout v6.18-rc3
> b4 am -3 49af6d76-bcb7-4343-8903-390040e2c49b@kernel.org
> git am -3 ./v18_20250924_a_hindborg_rust_extend_module_macro_with_integer_parameter_support.mbx
>
> works fine on my end. Using `-3` should have the same effect as applying
> the series on top of the original base and rebase it.
Right, that's what I did but manually. I didn't know about that argument :).
>
> git fetch https://git.kernel.org/pub/scm/linux/kernel/git/modules/linux.git rebase/20250924-module-params-v3-v18-0-bf512c35d910@kernel.org
> git range-diff FETCH_HEAD...HEAD
>
> confirms that.
>
>> I've created a temporary branch with this rebase here:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/modules/linux.git/log/?h=rebase/20250924-module-params-v3-v18-0-bf512c35d910@kernel.org
>>
>> Can you take a look when you can? I'll merge this shortly after checking with
>> Uwe, as there are some minor conflicts with his tree.
>>
>> + Uwe
>>
>> These are the conflicts I see when merging the patch series from Michal [1]
>> (Introduce import_ns support for Rust). I believe these are trivial things that
>> we will get notified from linux-next merging. But let me know what you think as
>> you have requested in that thread.
>>
>> [1] Link: https://lore.kernel.org/all/20251028-pwm_fixes-v1-0-25a532d31998@samsung.com/
>
> Yeah, I expect that Stephen will highlight the conflicts, but I prefer
> to not be surprised by that and consider linux-next more a fallback
> security net that I don't want to use. I like it to be the other way
> round and tell Stephen about conflicts to expect :-)
Please Stephen, check the proposed changes below. I plan to merge this series in
modules' tree and it will conflict with Uwe's tree on rust/macros/module.rs file.
>
>> ...
>> Applying: rust: macros: Add support for 'imports_ns' to module!
>> Patch failed at 0008 rust: macros: Add support for 'imports_ns' to module!
>> error: patch failed: rust/macros/module.rs:98
>> error: rust/macros/module.rs: patch does not apply
>> hint: Use 'git am --show-current-patch=diff' to see the failed patch
>> hint: When you have resolved this problem, run "git am --continue".
>> hint: If you prefer to skip this patch, run "git am --skip" instead.
>> hint: To restore the original branch and stop patching, run "git am --abort".
>> hint: Disable this message with "git config set advice.mergeConflict false"
>>
>> git am --show-current-patch=diff
>
> That command shows the patch to apply, but not the conflict, let alone
> your resolution.
>
>> ---
>> rust/macros/module.rs | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>> ---
>> rust/macros/module.rs | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/rust/macros/module.rs b/rust/macros/module.rs
>> index 5ee54a00c0b65699596e660b2d4d60e64be2a50c..408cd115487514c8be79724d901c676435696376 100644
>> --- a/rust/macros/module.rs
>> +++ b/rust/macros/module.rs
>> @@ -98,6 +98,7 @@ struct ModuleInfo {
>> description: Option<String>,
>> alias: Option<Vec<String>>,
>> firmware: Option<Vec<String>>,
>> + imports_ns: Option<Vec<String>>,
>> }
>
> So here the addition of `params` is missing.
>
>> [...]
>
> When I merge your branch mentioned above with my pwm/for-next and
> resolve the merge conflicts, the resolution looks as follows. The only
> non-trivial thing is that
>
> if let Some(imports) = info.imports_ns {
>
> now needs a & for `info`.
Correct.
In case it's necessary, I've merged your changes into the modules's -next
branch and attach the diff for you and Stephen. Not sure which order trees are
taken/merged, though.
>
> Best regards
> Uwe
>
> diff --cc rust/macros/module.rs
> index d62e9c1e2a89,408cd1154875..000000000000
> --- a/rust/macros/module.rs
> +++ b/rust/macros/module.rs
> @@@ -205,50 -98,7 +205,51 @@@ struct ModuleInfo
> description: Option<String>,
> alias: Option<Vec<String>>,
> firmware: Option<Vec<String>>,
> + imports_ns: Option<Vec<String>>,
> + params: Option<Vec<Parameter>>,
> +}
> +
> +#[derive(Debug)]
> +struct Parameter {
> + name: String,
> + ptype: String,
> + default: String,
> + description: String,
> +}
> +
> +fn expect_params(it: &mut token_stream::IntoIter) -> Vec<Parameter> {
> + let params = expect_group(it);
> + assert_eq!(params.delimiter(), Delimiter::Brace);
> + let mut it = params.stream().into_iter();
> + let mut parsed = Vec::new();
> +
> + loop {
> + let param_name = match it.next() {
> + Some(TokenTree::Ident(ident)) => ident.to_string(),
> + Some(_) => panic!("Expected Ident or end"),
> + None => break,
> + };
> +
> + assert_eq!(expect_punct(&mut it), ':');
> + let param_type = expect_ident(&mut it);
> + let group = expect_group(&mut it);
> + assert_eq!(group.delimiter(), Delimiter::Brace);
> + assert_eq!(expect_punct(&mut it), ',');
> +
> + let mut param_it = group.stream().into_iter();
> + let param_default = expect_param_default(&mut param_it);
> + let param_description = expect_string_field(&mut param_it, "description");
> + expect_end(&mut param_it);
> +
> + parsed.push(Parameter {
> + name: param_name,
> + ptype: param_type,
> + default: param_default,
> + description: param_description,
> + })
> + }
> +
> + parsed
> }
>
> impl ModuleInfo {
> @@@ -263,7 -113,7 +264,8 @@@
> "license",
> "alias",
> "firmware",
> + "imports_ns",
> + "params",
> ];
> const REQUIRED_KEYS: &[&str] = &["type", "name", "license"];
> let mut seen_keys = Vec::new();
> @@@ -289,7 -139,7 +291,8 @@@
> "license" => info.license = expect_string_ascii(it),
> "alias" => info.alias = Some(expect_string_array(it)),
> "firmware" => info.firmware = Some(expect_string_array(it)),
> + "imports_ns" => info.imports_ns = Some(expect_string_array(it)),
> + "params" => info.params = Some(expect_params(it)),
> _ => panic!("Unknown key \"{key}\". Valid keys are: {EXPECTED_KEYS:?}."),
> }
>
> @@@ -329,25 -179,30 +332,30 @@@ pub(crate) fn module(ts: TokenStream) -
> // Rust does not allow hyphens in identifiers, use underscore instead.
> let ident = info.name.replace('-', "_");
> let mut modinfo = ModInfoBuilder::new(ident.as_ref());
> - if let Some(authors) = info.authors {
> + if let Some(authors) = &info.authors {
> for author in authors {
> - modinfo.emit("author", &author);
> + modinfo.emit("author", author);
> }
> }
> - if let Some(description) = info.description {
> - modinfo.emit("description", &description);
> + if let Some(description) = &info.description {
> + modinfo.emit("description", description);
> }
> modinfo.emit("license", &info.license);
> - if let Some(aliases) = info.alias {
> + if let Some(aliases) = &info.alias {
> for alias in aliases {
> - modinfo.emit("alias", &alias);
> + modinfo.emit("alias", alias);
> }
> }
> - if let Some(firmware) = info.firmware {
> + if let Some(firmware) = &info.firmware {
> for fw in firmware {
> - modinfo.emit("firmware", &fw);
> + modinfo.emit("firmware", fw);
> }
> }
> - if let Some(imports) = info.imports_ns {
> ++ if let Some(imports) = &info.imports_ns {
> + for ns in imports {
> + modinfo.emit("import_ns", &ns);
> + }
> + }
>
> // Built-in modules also export the `file` modinfo string.
> let file =
The resolution looks good to me.
As I applied Michal's patch on top of Andreas changes, it looks like this on
my side:
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index d62e9c1e2a89..5bf0a487de50 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -206,6 +206,7 @@ struct ModuleInfo {
alias: Option<Vec<String>>,
firmware: Option<Vec<String>>,
params: Option<Vec<Parameter>>,
+ imports_ns: Option<Vec<String>>,
}
#[derive(Debug)]
@@ -264,6 +265,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
"alias",
"firmware",
"params",
+ "imports_ns",
];
const REQUIRED_KEYS: &[&str] = &["type", "name", "license"];
let mut seen_keys = Vec::new();
@@ -290,6 +292,7 @@ fn parse(it: &mut token_stream::IntoIter) -> Self {
"alias" => info.alias = Some(expect_string_array(it)),
"firmware" => info.firmware = Some(expect_string_array(it)),
"params" => info.params = Some(expect_params(it)),
+ "imports_ns" => info.imports_ns = Some(expect_string_array(it)),
_ => panic!("Unknown key \"{key}\". Valid keys are: {EXPECTED_KEYS:?}."),
}
@@ -348,6 +351,11 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
modinfo.emit("firmware", fw);
}
}
+ if let Some(imports) = &info.imports_ns {
+ for ns in imports {
+ modinfo.emit("import_ns", &ns);
+ }
+ }
// Built-in modules also export the `file` modinfo string.
let file =
^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
` (7 preceding siblings ...)
2025-11-01 21:39 ` [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Daniel Gomez
@ 2025-11-03 14:47 ` Daniel Gomez
8 siblings, 0 replies; 12+ messages in thread
From: Daniel Gomez @ 2025-11-03 14:47 UTC (permalink / raw)
To: Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Alice Ryhl, Masahiro Yamada,
Nathan Chancellor, Luis Chamberlain, Danilo Krummrich,
Benno Lossin, Benno Lossin, Nicolas Schier, Andreas Hindborg
Cc: Trevor Gross, Adam Bratschi-Kaye, rust-for-linux, linux-kernel,
linux-kbuild, Petr Pavlu, Sami Tolvanen, Daniel Gomez,
Simona Vetter, Greg KH, Fiona Behrens, Daniel Almeida,
linux-modules
On Wed, 24 Sep 2025 14:39:23 +0200, Andreas Hindborg wrote:
> Extend the `module!` macro with support module parameters. Also add some
> string to integer parsing functions.
>
> Based on the original module parameter support by Miguel [1],
> later extended and generalized by Adam for more types [2][3].
> Originally tracked at [4].
>
> [...]
Applied, thanks!
[1/7] rust: sync: add `SetOnce`
commit: 821fe7bf16c57d690f4f92997f4e51abb93e0347
[2/7] rust: str: add radix prefixed integer parsing functions
commit: 51d9ee90ea9060be240830eb28f5f117ad00318c
[3/7] rust: introduce module_param module
commit: 0b08fc292842a13aa496413b48c1efb83573b8c6
[4/7] rust: module: use a reference in macros::module::module
commit: 3809d7a89fe550bf4065c04adff6dac610daddad
[5/7] rust: module: update the module macro with module parameter support
commit: 0b24f9740f26ac7ad91ac0f4de27717c14de91bd
[6/7] rust: samples: add a module parameter to the rust_minimal sample
commit: e119c2fe8c78632188f6cdeae620951a7032855a
[7/7] modules: add rust modules files to MAINTAINERS
commit: ee3b8134b2bae848e03e56c090ceca4ae76cee06
Best regards,
--
Daniel Gomez <da.gomez@kernel.org>
^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2025-11-03 14:47 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-09-24 12:39 [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 1/7] rust: sync: add `SetOnce` Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 2/7] rust: str: add radix prefixed integer parsing functions Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 3/7] rust: introduce module_param module Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 4/7] rust: module: use a reference in macros::module::module Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 5/7] rust: module: update the module macro with module parameter support Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 6/7] rust: samples: add a module parameter to the rust_minimal sample Andreas Hindborg
2025-09-24 12:39 ` [PATCH v18 7/7] modules: add rust modules files to MAINTAINERS Andreas Hindborg
2025-11-01 21:39 ` [PATCH v18 0/7] rust: extend `module!` macro with integer parameter support Daniel Gomez
2025-11-02 9:56 ` Uwe Kleine-König
2025-11-02 21:19 ` Daniel Gomez
2025-11-03 14:47 ` Daniel Gomez
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