Commit Graph

535 Commits

Author SHA1 Message Date
Danilo Krummrich
4d320e30ee rust: platform: fix unrestricted &mut platform::Device
As by now, platform::Device is implemented as:

	#[derive(Clone)]
	pub struct Device(ARef<device::Device>);

This may be convenient, but has the implication that drivers can call
device methods that require a mutable reference concurrently at any
point of time.

Instead define platform::Device as

	pub struct Device<Ctx: DeviceContext = Normal>(
		Opaque<bindings::platform_dev>,
		PhantomData<Ctx>,
	);

and manually implement the AlwaysRefCounted trait.

With this we can implement methods that should only be called from
bus callbacks (such as probe()) for platform::Device<Core>. Consequently,
we make this type accessible in bus callbacks only.

Arbitrary references taken by the driver are still of type
ARef<platform::Device> and hence don't provide access to methods that are
reserved for bus callbacks.

Fixes: 683a63befc ("rust: platform: add basic platform device / driver abstractions")
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250314160932.100165-5-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-17 08:04:25 +01:00
Danilo Krummrich
7b948a2af6 rust: pci: fix unrestricted &mut pci::Device
As by now, pci::Device is implemented as:

	#[derive(Clone)]
	pub struct Device(ARef<device::Device>);

This may be convenient, but has the implication that drivers can call
device methods that require a mutable reference concurrently at any
point of time.

Instead define pci::Device as

	pub struct Device<Ctx: DeviceContext = Normal>(
		Opaque<bindings::pci_dev>,
		PhantomData<Ctx>,
	);

and manually implement the AlwaysRefCounted trait.

With this we can implement methods that should only be called from
bus callbacks (such as probe()) for pci::Device<Core>. Consequently, we
make this type accessible in bus callbacks only.

Arbitrary references taken by the driver are still of type
ARef<pci::Device> and hence don't provide access to methods that are
reserved for bus callbacks.

Fixes: 1bd8b6b2c5 ("rust: pci: add basic PCI device / driver abstractions")
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250314160932.100165-4-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-17 08:04:25 +01:00
Danilo Krummrich
4d032779ab rust: device: implement device context marker
Some bus device functions should only be called from bus callbacks,
such as probe(), remove(), resume(), suspend(), etc.

To ensure this add device context marker structs, that can be used as
generics for bus device implementations.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Suggested-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250314160932.100165-3-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-17 08:04:25 +01:00
Danilo Krummrich
d1f6d6c537 rust: pci: use to_result() in enable_device_mem()
Simplify enable_device_mem() by using to_result() to handle the return
value of the corresponding FFI call.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250314160932.100165-2-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-17 08:04:25 +01:00
Benno Lossin
dbd5058ba6 rust: make pin-init its own crate
Rename relative paths inside of the crate to still refer to the same
items, also rename paths inside of the kernel crate and adjust the build
system to build the crate.

[ Remove the `expect` (and thus the `lint_reasons` feature) since
  the tree now uses `quote!` from `rust/macros/export.rs`. Remove the
  `TokenStream` import removal, since it is now used as well.

  In addition, temporarily (i.e. just for this commit) use an `--extern
  force:alloc` to prevent an unknown `new_uninit` error in the `rustdoc`
  target. For context, please see a similar case in:

      https://lore.kernel.org/lkml/20240422090644.525520-1-ojeda@kernel.org/

  And adjusted the message above. - Miguel ]

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:19 +01:00
Benno Lossin
129e97be8e rust: pin-init: fix documentation links
Before switching to compile the `pin-init` crate directly, change
any links that would be invalid to links that are valid both before and
after the switch.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-12-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:19 +01:00
Benno Lossin
5657c3a9fa rust: add ZeroableOption and implement it instead of Zeroable for Option<Box<T, A>>
When making pin-init its own crate, `Zeroable` will no longer be defined
by the kernel crate and thus implementing it for `Option<Box<T, A>>` is
no longer possible due to the orphan rule.
For this reason introduce a new `ZeroableOption` trait that circumvents
this problem.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-11-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
9d29c682f0 rust: pin-init: move impl Zeroable for Opaque and Option<KBox<T>> into the kernel crate
In order to make pin-init a standalone crate, move kernel-specific code
directly into the kernel crate. Since `Opaque<T>` and `KBox<T>` are part
of the kernel, move their `Zeroable` implementation into the kernel
crate.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20250308110339.2997091-10-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
114ca41fe7 rust: pin-init: move InPlaceInit and impls of InPlaceWrite into the kernel crate
In order to make pin-init a standalone crate, move kernel-specific code
directly into the kernel crate. This includes the `InPlaceInit<T>`
trait, its implementations and the implementations of `InPlaceWrite` for
`Arc` and `UniqueArc`. All of these use the kernel's error type which
will become unavailable in pin-init.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-9-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
578eb8b6db rust: pin-init: move the default error behavior of try_[pin_]init
Move the ability to just write `try_pin_init!(Foo { a <- a_init })`
(note the missing `? Error` at the end) into the kernel crate.
Remove this notation from the pin-init crate, since the default when no
error is specified is the kernel-internal `Error` type. Instead add two
macros in the kernel crate that serve this default and are used instead
of the ones from `pin-init`.

This is done, because the `Error` type that is used as the default is
from the kernel crate and it thus prevents making the pin-init crate
standalone.

In order to not cause a build error due to a name overlap, the macros in
the pin-init crate are renamed, but this change is reverted in a future
commit when it is a standalone crate.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-8-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
86f7dacade rust: add extensions to the pin-init crate and move relevant documentation there
In preparation of splitting off the pin-init crate from the kernel
crate, move all kernel-specific documentation from pin-init back into
the kernel crate.

Also include an example from the user-space version [1] adapted to the
kernel.

The new `init.rs` file will also be populated by kernel-specific
extensions to the pin-init crate by the next commits.

Link: c1417c64c7/src/lib.rs (L161) [1]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-4-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
fbf8fb328d rust: move pin-init API into its own directory
In preparation of splitting off the pin-init crate from the kernel
crate, move all pin-init API code (including proc-macros) into
`rust/pin-init`.

Moved modules have their import path adjusted via the `#[path = "..."]`
attribute. This allows the files to still be imported in the kernel
crate even though the files are in different directories.

Code that is moved out of files (but the file itself stays where it is)
is imported via the `include!` macro. This also allows the code to be
moved while still being part of the kernel crate.

Note that this commit moves the generics parsing code out of the GPL-2.0
file `rust/macros/helpers.rs` into the Apache-2.0 OR MIT file
`rust/pin_init/internal/src/helpers.rs`. I am the sole author of that
code and it already is available with that license at [1].
The same is true for the entry-points of the proc-macros `pin_data`,
`pinned_drop` and `derive_zeroable` in `rust/macros/lib.rs` that are
moved to `rust/pin_data/internal/src/lib.rs`. Although there are some
smaller patches that fix the doctests.

Link: https://github.com/Rust-for-Linux/pinned-init [1]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-3-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
206dea39e5 rust: init: disable doctests
The build system cannot handle doctests in the kernel crate in files
outside of `rust/kernel/`. Subsequent commits will move files out of
that directory, but will still compile them as part of the kernel crate.
Thus ignore all doctests in the to-be-moved files.

Leave tests disabled until they are separated into their own crate and
they stop causing breakage.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-2-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Dirk Behme
dc60dd0c68 rust: error: extend the Result documentation
Extend the Result documentation by some guidelines and examples how
to handle Result error cases gracefully. And how to not handle them.

While at it fix one missing `Result` link in the existing documentation.

[ Moved links out-of-line for improved readability. Fixed `srctree`
  link. Sorted out-of-line links. Added newlines for consistency
  with other docs. Applied paragraph break suggestion. Reworded
  slightly the docs in a couple places. Added Markdown.

  In addition, added `#[allow(clippy::single_match)` for the first
  example. It cannot be an `expect` since due to a difference introduced
  in Rust 1.85.0 when there are comments in the arms of the `match`.
  Reported it upstream, but it was intended:

      https://github.com/rust-lang/rust-clippy/issues/14418

  Perhaps Clippy will lint about it in the future, but without autofix:

      https://github.com/rust-lang/rust-clippy/pull/14420

    - Miguel ]

Link: https://lore.kernel.org/rust-for-linux/CANiq72keOdXy0LFKk9SzYWwSjiD710v=hQO4xi+5E4xNALa6cA@mail.gmail.com/
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20250122054719.595878-1-dirk.behme@de.bosch.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 20:54:08 +01:00
Linus Torvalds
cd3a56ac2d Merge tag 'rust-fixes-6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull rust fixes from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Disallow BTF generation with Rust + LTO

   - Improve rust-analyzer support

  'kernel' crate:

   - 'init' module: remove 'Zeroable' implementation for a couple types
     that should not have it

   - 'alloc' module: fix macOS failure in host test by satisfying POSIX
     alignment requirement

   - Add missing '\n's to 'pr_*!()' calls

  And a couple other minor cleanups"

* tag 'rust-fixes-6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
  scripts: generate_rust_analyzer: add uapi crate
  scripts: generate_rust_analyzer: add missing include_dirs
  scripts: generate_rust_analyzer: add missing macros deps
  rust: Disallow BTF generation with Rust + LTO
  rust: task: fix `SAFETY` comment in `Task::wake_up`
  rust: workqueue: add missing newline to pr_info! examples
  rust: sync: add missing newline in locked_by log example
  rust: init: add missing newline to pr_info! calls
  rust: error: add missing newline to pr_warn! calls
  rust: docs: add missing newline to printing macro examples
  rust: alloc: satisfy POSIX alignment requirement
  rust: init: fix `Zeroable` implementation for `Option<NonNull<T>>` and `Option<KBox<T>>`
  rust: remove leftover mentions of the `alloc` crate
2025-03-15 15:40:42 -10:00
Andreas Hindborg
d7bf4786b5 rust: hrtimer: implement HrTimerPointer for Arc
Allow the use of intrusive `hrtimer` fields in structs that are managed by
an `Arc` by implementing `HrTimerPointer` and `RawTimerCallbck` for `Arc`.

Acked-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-3-73586e2bd5f1@kernel.org
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-11 21:00:42 +01:00
Andreas Hindborg
a0c6fa8b8a rust: sync: add Arc::as_ptr
Add a method to get a pointer to the data contained in an `Arc`.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-2-73586e2bd5f1@kernel.org
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-11 21:00:42 +01:00
Andreas Hindborg
8a8afe9349 rust: hrtimer: introduce hrtimer support
Add support for intrusive use of the hrtimer system. For now,
only add support for embedding one timer per Rust struct.

The hrtimer Rust API is based on the intrusive style pattern introduced by
the Rust workqueue API.

Acked-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-1-73586e2bd5f1@kernel.org
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-11 21:00:28 +01:00
Ethan Carter Edwards
10b20f2d1b rust/kernel/faux: mark Registration methods inline
When building the kernel on Arch Linux using on x86_64 with tools:
$ rustc --version
rustc 1.84.0 (9fc6b4312 2025-01-07)
$ clang --version
clang version 19.1.7
Target: x86_64-pc-linux-gnu

The following symbols are generated:
$ nm vmlinux | rg ' _R' | rustfilt | rg faux
ffffffff81959ae0 T <kernel::faux::Registration>::new
ffffffff81959b40 T <kernel::faux::Registration as core::ops::drop::Drop>::drop

However, these Rust symbols are wrappers around bindings in the C faux
code. Inlining these functions removes the middle-man wrapper function
After applying this patch, the above function signatures disappear.

Link: https://github.com/Rust-for-Linux/linux/issues/1145
Signed-off-by: Ethan Carter Edwards <ethan@ethancedwards.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/jesg4yu7m6fvzmgg5tlsktrrjm36l4qsranto5mdmnucx4pvf3@nhvt4juw5es3
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-11 10:42:23 +01:00
Panagiotis Foliadis
6fbafe1cbe rust: task: fix SAFETY comment in Task::wake_up
The `SAFETY` comment inside the `wake_up` method references
erroneously the `signal_pending` C function instead of the
`wake_up_process` which is actually called.

Fix the comment to reference the correct C function.

Fixes: fe95f58320 ("rust: task: adjust safety comments in Task methods")
Signed-off-by: Panagiotis Foliadis <pfoliadis@posteo.net>
Reviewed-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250308-comment-fix-v1-1-4bba709fd36d@posteo.net
[ Slightly reworded. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-10 18:07:40 +01:00
Dirk Behme
ab2ebb7bc9 rust: types: add intra-doc links for Opaque<T>
We use intra-doc links wherever possible. Thus add a couple missing ones
for `Opaque<T>`.

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250305053438.1532397-1-dirk.behme@de.bosch.com
[ Reworded. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-10 15:24:05 +01:00
Guilherme Giacomo Simoes
38559da6af rust: module: introduce authors key
In the `module!` macro, the `author` field is currently of type `String`.

Since modules can have multiple authors, this limitation prevents
specifying more than one.

Add an `authors` field as `Option<Vec<String>>` to allow creating
modules with multiple authors, and change the documentation and all
current users to use it. Eventually, the single `author` field may
be removed.

[ The `modinfo` key needs to still be `author`; otherwise, tooling
  may not work properly, e.g.:

      $ modinfo --author samples/rust/rust_print.ko
      Rust for Linux Contributors

  I have also kept the original `author` field (undocumented), so
  that we can drop it more easily in a kernel cycle or two.

    - Miguel ]

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/244
Reviewed-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Guilherme Giacomo Simoes <trintaeoitogc@gmail.com>
Link: https://lore.kernel.org/r/20250309175712.845622-2-trintaeoitogc@gmail.com
[ Fixed `modinfo` key. Kept `author` field. Reworded message
  accordingly. Updated my email. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-10 15:12:17 +01:00
Greg Kroah-Hartman
046cc01be6 Merge 6.14-rc6 into char-misc-next
We need the fixes in here as well to build on top of.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-10 07:31:51 +01:00
Alice Ryhl
92d2873bed print: use new #[export] macro for rust_fmt_argument
This moves the rust_fmt_argument function over to use the new #[export]
macro, which will verify at compile-time that the function signature
matches what is in the header file.

Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250303-export-macro-v3-4-41fbad85a27f@google.com
[ Removed period as requested by Andy. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-09 20:52:46 +01:00
Alice Ryhl
44e333fe46 rust: add #[export] macro
Rust has two different tools for generating function declarations to
call across the FFI boundary:

* bindgen. Generates Rust declarations from a C header.
* cbindgen. Generates C headers from Rust declarations.

However, we only use bindgen in the kernel. This means that when C code
calls a Rust function by name, its signature must be duplicated in both
Rust code and a C header, and the signature needs to be kept in sync
manually.

Introducing cbindgen as a mandatory dependency to build the kernel would
be a rather complex and large change, so we do not consider that at this
time. Instead, to eliminate this manual checking, introduce a new macro
that verifies at compile time that the two function declarations use the
same signature. The idea is to run the C declaration through bindgen,
and then have rustc verify that the function pointers have the same
type.

The signature must still be written twice, but at least you can no
longer get it wrong. If the signatures don't match, you will get errors
that look like this:

error[E0308]: `if` and `else` have incompatible types
  --> <linux>/rust/kernel/print.rs:22:22
   |
21 | #[export]
   | --------- expected because of this
22 | unsafe extern "C" fn rust_fmt_argument(
   |                      ^^^^^^^^^^^^^^^^^ expected `u8`, found `i8`
   |
   = note: expected fn item `unsafe extern "C" fn(*mut u8, *mut u8, *mut c_void) -> *mut u8 {bindings::rust_fmt_argument}`
              found fn item `unsafe extern "C" fn(*mut i8, *mut i8, *const c_void) -> *mut i8 {print::rust_fmt_argument}`

It is unfortunate that the error message starts out by saying "`if` and
`else` have incompatible types", but I believe the rest of the error
message is reasonably clear and not too confusing.

Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250303-export-macro-v3-3-41fbad85a27f@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-09 20:52:46 +01:00
Alice Ryhl
901b3290bd rust: fix signature of rust_fmt_argument
Without this change, the rest of this series will emit the following
error message:

error[E0308]: `if` and `else` have incompatible types
  --> <linux>/rust/kernel/print.rs:22:22
   |
21 | #[export]
   | --------- expected because of this
22 | unsafe extern "C" fn rust_fmt_argument(
   |                      ^^^^^^^^^^^^^^^^^ expected `u8`, found `i8`
   |
   = note: expected fn item `unsafe extern "C" fn(*mut u8, *mut u8, *mut c_void) -> *mut u8 {bindings::rust_fmt_argument}`
              found fn item `unsafe extern "C" fn(*mut i8, *mut i8, *const c_void) -> *mut i8 {print::rust_fmt_argument}`

The error may be different depending on the architecture.

To fix this, change the void pointer argument to use a const pointer,
and change the imports to use crate::ffi instead of core::ffi for
integer types.

Fixes: 787983da77 ("vsprintf: add new `%pA` format specifier")
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250303-export-macro-v3-1-41fbad85a27f@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-09 20:52:46 +01:00
Danilo Krummrich
1d121a33ad rust: firmware: add module_firmware! macro
Analogous to the `module!` macro `module_firmware!` adds additional
firmware path strings to the .modinfo section.

In contrast to `module!`, where path strings need to be string literals,
path strings can be composed with the `firmware::ModInfoBuilder`.

Some drivers require a lot of firmware files (such as nova-core) and
hence benefit from more flexibility composing firmware path strings.

Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lore.kernel.org/r/20250306222336.23482-4-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-03-09 19:23:31 +01:00
Danilo Krummrich
ef476b0dd9 rust: firmware: introduce firmware::ModInfoBuilder
The `firmware` field of the `module!` only accepts literal strings,
which is due to the fact that it is implemented as a proc macro.

Some drivers require a lot of firmware files (such as nova-core) and
hence benefit from more flexibility composing firmware path strings.

The `firmware::ModInfoBuilder` is a helper component to flexibly compose
firmware path strings for the .modinfo section in const context.

It is meant to be used in combination with `kernel::module_firmware!`.

Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250306222336.23482-3-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-03-09 19:21:08 +01:00
Borys Tyran
cd1ed11a67 rust: improve lifetimes markup
Improve lifetimes markup; e.g. from:

    /// ... 'a ...

to:

    /// ... `'a` ...

This will make lifetimes display as code span with Markdown and make it
more consistent with rest of the docs.

Link: https://github.com/Rust-for-Linux/linux/issues/1138
Signed-off-by: Borys Tyran <borys.tyran@protonmail.com>
Link: https://lore.kernel.org/r/20250207142437.112435-1-borys.tyran@protonmail.com
[ Reworded and changed Closes tag to Link. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-08 23:04:38 +01:00
Alice Ryhl
52ae96f518 rust: list: make the cursor point between elements
I've been using the linked list cursor for a few different things, and I
find it inconvenient to use because all of the functions have signatures
along the lines of `Self -> Option<Self>`. The root cause of these
signatures is that the cursor points *at* an element, rather than
*between* two elements.

Thus, change the cursor API to point between two elements. This is
inspired by the stdlib linked list (well, really by this guy [1]), which
also uses cursors that point between elements.

The `peek_next` method returns a helper that lets you look at and
optionally remove the element, as one common use-case of cursors is to
iterate a list to look for an element, then remove that element.

For many of the methods, this will reduce how many we need since they
now just need a prev/next method, instead of the current state where you
may end up needing all of curr/prev/next. Also, if we decide to add a
function for splitting a list into two lists at the cursor, then a
cursor that points between elements is exactly what makes the most
sense.

Another advantage is that this means you can now have a cursor into an
empty list.

Link: https://rust-unofficial.github.io/too-many-lists/sixth-cursors-intro.html [1]
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250210-cursor-between-v7-2-36f0215181ed@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-08 22:35:34 +01:00
Alice Ryhl
998c65733b rust: list: extract common code for insertion
To prepare for a new cursor API that has the ability to insert elements
into the list, extract the common code needed for this operation into a
new `insert_inner` method.

Both `push_back` and `push_front` are updated to use the new function.

Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250210-cursor-between-v7-1-36f0215181ed@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-08 22:35:34 +01:00
Mitchell Levy
f73ca66f0d rust: lockdep: Use Pin for all LockClassKey usages
Reintroduce dynamically-allocated LockClassKeys such that they are
automatically (de)registered. Require that all usages of LockClassKeys
ensure that they are Pin'd.

Currently, only `'static` LockClassKeys are supported, so Pin is
redundant. However, it is intended that dynamically-allocated
LockClassKeys will eventually be supported, so using Pin from the outset
will make that change simpler.

Closes: https://github.com/Rust-for-Linux/linux/issues/1102
Suggested-by: Benno Lossin <benno.lossin@proton.me>
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Mitchell Levy <levymitchell0@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250307232717.1759087-12-boqun.feng@gmail.com
2025-03-08 00:55:04 +01:00
Alice Ryhl
70b9c8563c rust: sync: condvar: Add wait_interruptible_freezable()
To support waiting for a `CondVar` as a freezable process, add a
wait_interruptible_freezable() function.

Binder needs this function in the appropriate places to freeze a process
where some of its threads are blocked on the Binder driver.

[ Boqun: Cleaned up the changelog and documentation. ]

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250307232717.1759087-10-boqun.feng@gmail.com
2025-03-08 00:55:04 +01:00
Boqun Feng
c2849afafd rust: sync: lock: Add an example for Guard:: Lock_ref()
To provide examples on usage of `Guard::lock_ref()` along with the unit
test, an "assert a lock is held by a guard" example is added.

(Also apply feedback from Benno.)

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250223072114.3715-1-boqun.feng@gmail.com
Link: https://lore.kernel.org/r/20250307232717.1759087-9-boqun.feng@gmail.com
2025-03-08 00:55:04 +01:00
Alice Ryhl
8f65291dae rust: sync: Add accessor for the lock behind a given guard
In order to assert a particular `Guard` is associated with a particular
`Lock`, add an accessor to obtain a reference to the underlying `Lock`
of a `Guard`.

Binder needs this assertion to ensure unsafe list operations are done
with the correct lock held.

[Boqun: Capitalize the title and reword the commit log]

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20250205-guard-get-lock-v2-1-ba32a8c1d5b7@google.com
Link: https://lore.kernel.org/r/20250307232717.1759087-8-boqun.feng@gmail.com
2025-03-08 00:55:04 +01:00
Mitchell Levy
966944f371 rust: lockdep: Remove support for dynamically allocated LockClassKeys
Currently, dynamically allocated LockCLassKeys can be used from the Rust
side without having them registered. This is a soundness issue, so
remove them.

Fixes: 6ea5aa0885 ("rust: sync: introduce `LockClassKey`")
Suggested-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Mitchell Levy <levymitchell0@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250307232717.1759087-11-boqun.feng@gmail.com
2025-03-08 00:52:00 +01:00
Alice Ryhl
74fc34937d rust: miscdevice: change how f_ops vtable is constructed
I was helping someone with writing a new Rust abstraction, and we were
using the miscdevice abstraction as an example. While doing this, it
became clear to me that the way I implemented the f_ops vtable is
confusing to new Rust users, and that the approach used by the block
abstractions is less confusing.

Thus, update the miscdevice abstractions to use the same approach as
rust/kernel/block/mq/operations.rs.

Sorry about the large diff. This changes the indentation of a large
amount of code.

Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250227-miscdevice-fops-change-v1-1-c9e9b75d67eb@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-07 18:20:36 +01:00
Alice Ryhl
6ad64bf917 rust: task: make Pid type alias public
The Pid type alias represents the integer type used for pids in the
kernel. It's the Rust equivalent to pid_t, and there are various methods
on Task that use Pid as the return type.

Binder needs to use Pid as the type for function arguments and struct
fields in many places. Thus, make the type public so that Binder can
access it.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20250130-task-pid-pub-v1-1-508808bcfcdc@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-06 20:59:45 +01:00
Gary Guo
41b6a8122d rust: alloc: make ReallocFunc::call inline
This function can be called with different function pointers when
different allocator (e.g. Kmalloc, Vmalloc, KVmalloc), however since
this function is not polymorphic, only one instance is generated,
and function pointers are used. Given that this function is called
for any Rust-side allocation/deallocation, performance matters a lot,
so making this function inlineable.

This is discovered when doing helper inlining work, since it's discovered
that even with helpers inlined, rust_helper_ symbols are still present
in final vmlinux binary, and it turns out this function is inhibiting
the inlining, and introducing indirect function calls.

Signed-off-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250105194054.545201-4-gary@garyguo.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-06 20:49:06 +01:00
Alban Kurti
0ea4c39064 rust: workqueue: add missing newline to pr_info! examples
The documentation examples in rust/kernel/workqueue.rs use pr_info!
calls that lack a trailing newline. To maintain consistency with
kernel logging practices, this patch adds the newline to all
affected examples.

Fixes: 15b286d1fd ("rust: workqueue: add examples")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1139
Signed-off-by: Alban Kurti <kurti@invicto.ai>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250206-printing_fix-v3-5-a85273b501ae@invicto.ai
[ Replaced Closes with Link since it fixes part of the issue. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-06 20:44:06 +01:00
Alban Kurti
50c3e77eb3 rust: sync: add missing newline in locked_by log example
The pr_info! example in rust/kernel/sync/locked_by.rs was missing
a newline. This patch appends the missing newline to ensure
that log messages for locked resources display correctly.

Fixes: 7b1f55e3a9 ("rust: sync: introduce `LockedBy`")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1139
Signed-off-by: Alban Kurti <kurti@invicto.ai>
Link: https://lore.kernel.org/r/20250206-printing_fix-v3-4-a85273b501ae@invicto.ai
[ Replaced Closes with Link since it fixes part of the issue. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-06 20:44:06 +01:00
Alban Kurti
6933c1067f rust: init: add missing newline to pr_info! calls
Several pr_info! calls in rust/kernel/init.rs (both in code examples
and macro documentation) were missing a newline, causing logs to
run together. This commit updates these calls to include a trailing
newline, improving readability and consistency with the C side.

Fixes: 6841d45a30 ("rust: init: add `stack_pin_init!` macro")
Fixes: 7f8977a7fe ("rust: init: add `{pin_}chain` functions to `{Pin}Init<T, E>`")
Fixes: d0fdc39612 ("rust: init: add `PinnedDrop` trait and macros")
Fixes: 4af84c6a85 ("rust: init: update expanded macro explanation")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1139
Signed-off-by: Alban Kurti <kurti@invicto.ai>
Link: https://lore.kernel.org/r/20250206-printing_fix-v3-3-a85273b501ae@invicto.ai
[ Replaced Closes with Link since it fixes part of the issue. Added
  one more Fixes tag (still same set of stable kernels). - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-06 20:42:52 +01:00
Alban Kurti
6f5c36f56d rust: error: add missing newline to pr_warn! calls
Added missing newline at the end of pr_warn! usage
so the log is not missed.

Fixes: 6551a7fe0a ("rust: error: Add Error::from_errno{_unchecked}()")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1139
Signed-off-by: Alban Kurti <kurti@invicto.ai>
Link: https://lore.kernel.org/r/20250206-printing_fix-v3-2-a85273b501ae@invicto.ai
[ Replaced Closes with Link since it fixes part of the issue. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-06 00:42:13 +01:00
Tamir Duberstein
ff64846bee rust: alloc: satisfy POSIX alignment requirement
ISO C's `aligned_alloc` is partially implementation-defined; on some
systems it inherits stricter requirements from POSIX's `posix_memalign`.

This causes the call added in commit dd09538fb4 ("rust: alloc:
implement `Cmalloc` in module allocator_test") to fail on macOS because
it doesn't meet the requirements of `posix_memalign`.

Adjust the call to meet the POSIX requirement and add a comment. This
fixes failures in `make rusttest` on macOS.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Cc: stable@vger.kernel.org
Fixes: dd09538fb4 ("rust: alloc: implement `Cmalloc` in module allocator_test")
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20250213-aligned-alloc-v7-1-d2a2d0be164b@gmail.com
[ Added Cc: stable. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-05 23:57:48 +01:00
Benno Lossin
df27cef153 rust: init: fix Zeroable implementation for Option<NonNull<T>> and Option<KBox<T>>
According to [1], `NonNull<T>` and `#[repr(transparent)]` wrapper types
such as our custom `KBox<T>` have the null pointer optimization only if
`T: Sized`. Thus remove the `Zeroable` implementation for the unsized
case.

Link: https://doc.rust-lang.org/stable/std/option/index.html#representation [1]
Reported-by: Alice Ryhl <aliceryhl@google.com>
Closes: https://lore.kernel.org/rust-for-linux/CAH5fLghL+qzrD8KiCF1V3vf2YcC6aWySzkmaE2Zzrnh1gKj-hw@mail.gmail.com/
Cc: stable@vger.kernel.org # v6.12+ (a custom patch will be needed for 6.6.y)
Fixes: 38cde0bd7b ("rust: init: add `Zeroable` trait and `init::zeroed` function")
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250305132836.2145476-1-benno.lossin@proton.me
[ Added Closes tag and moved up the Reported-by one. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-05 23:57:39 +01:00
Miguel Ojeda
374908a15a rust: remove leftover mentions of the alloc crate
In commit 392e34b6bc ("kbuild: rust: remove the `alloc` crate and
`GlobalAlloc`") we stopped using the upstream `alloc` crate.

Thus remove a few leftover mentions treewide.

Cc: stable@vger.kernel.org # Also to 6.12.y after the `alloc` backport lands
Fixes: 392e34b6bc ("kbuild: rust: remove the `alloc` crate and `GlobalAlloc`")
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250303171030.1081134-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-05 23:55:56 +01:00
Alice Ryhl
ab938b59e9 cred,rust: mark Credential methods inline
When you build the kernel using the llvm-19.1.4-rust-1.83.0-x86_64
toolchain provided by kernel.org with ARCH=arm64, the following symbols
are generated:

$ nm out-linux/vmlinux | grep ' _R'.*Credential | rustfilt
... T <kernel::cred::Credential>::get_secid
... T <kernel::cred::Credential as
        kernel::types::AlwaysRefCounted>::dec_ref
... T <kernel::cred::Credential as
        kernel::types::AlwaysRefCounted>::inc_ref

However, these Rust symbols are trivial wrappers around the functions
security_cred_getsecid, get_cred, and put_cred respectively. It doesn't
make sense to go through a trivial wrapper for these functions, so mark
them inline. Also mark other trivial methods inline to prevent similar
cases in the future.

After applying this patch, the above command will produce no output.

Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
[PM: subject tweak, description line trims]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-03-04 17:07:49 -05:00
Alice Ryhl
0a01beac92 lsm,rust: reword "destroy" -> "release" in SecurityCtx
What happens inside the individual LSMs for a given LSM hook can vary
quite a bit, so it is best to use the terminology "release" instead of
"destroy" or "free".

Suggested-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
[PM: subj tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-03-04 15:44:46 -05:00
Alice Ryhl
55e16418dd lsm,rust: mark SecurityCtx methods inline
When you build the kernel using the llvm-19.1.4-rust-1.83.0-x86_64
toolchain provided by kernel.org with ARCH=arm64, the following symbols
are generated:

$ nm vmlinux | grep ' _R'.*SecurityCtx | rustfilt
... T <kernel::security::SecurityCtx>::from_secid
... T <kernel::security::SecurityCtx as core::ops::drop::Drop>::drop

However, these Rust symbols are trivial wrappers around the functions
security_secid_to_secctx and security_release_secctx respectively. It
doesn't make sense to go through a trivial wrapper for these functions,
so mark them inline. Also mark other trivial methods inline to prevent
similar cases in the future.

After applying this patch, the above command will produce no output.

Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
[PM: trimmed long description lines, subj tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-03-04 15:42:36 -05:00
Lyude Paul
95cb0cb546 rust/faux: Add missing parent argument to Registration::new()
A little late in the review of the faux device interface, we added the
ability to specify a parent device when creating new faux devices - but
this never got ported over to the rust bindings. So, let's add the missing
argument now so we don't have to convert other users later down the line.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250227193522.198344-1-lyude@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-27 18:03:17 -08:00