In some cases, we need to call test-only code from outside the test
case, for example, to mock a function or a module.
In order to check whether we are in a test or not, we need to test if
`CONFIG_KUNIT` is set.
Unfortunately, we cannot rely only on this condition because:
- a test could be running in another thread,
- some distros compile KUnit in production kernels, so checking at runtime
that `current->kunit_test != NULL` is required.
Forturately, KUnit provides an optimised check in
`kunit_get_current_test()`, which checks CONFIG_KUNIT, a global static
key, and then the current thread's running KUnit test.
Add a safe wrapper function around this to know whether or not we are in
a KUnit test and examples showing how to mock a function and a module.
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Co-developed-by: David Gow <davidgow@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/r/20250307090103.918788-4-davidgow@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Add a new procedural macro (`#[kunit_tests(kunit_test_suit_name)]`) to
run KUnit tests using a user-space like syntax.
The macro, that should be used on modules, transforms every `#[test]`
in a `kunit_case!` and adds a `kunit_unsafe_test_suite!` registering
all of them.
The only difference with user-space tests is that instead of using
`#[cfg(test)]`, `#[kunit_tests(kunit_test_suit_name)]` is used.
Note that `#[cfg(CONFIG_KUNIT)]` is added so the test module is not
compiled when `CONFIG_KUNIT` is set to `n`.
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/r/20250307090103.918788-3-davidgow@google.com
[ Removed spurious (in rendered form) newline in docs. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Add a couple of Rust const functions and macros to allow to develop
KUnit tests without relying on generated C code:
- The `kunit_unsafe_test_suite!` Rust macro is similar to the
`kunit_test_suite` C macro. It requires a NULL-terminated array of
test cases (see below).
- The `kunit_case` Rust function is similar to the `KUNIT_CASE` C macro.
It generates as case from the name and function.
- The `kunit_case_null` Rust function generates a NULL test case, which
is to be used as delimiter in `kunit_test_suite!`.
While these functions and macros can be used on their own, a future
patch will introduce another macro to create KUnit tests using a
user-space like syntax.
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Co-developed-by: Matt Gilbride <mattgilbride@google.com>
Signed-off-by: Matt Gilbride <mattgilbride@google.com>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Co-developed-by: David Gow <davidgow@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/r/20250307090103.918788-2-davidgow@google.com
[ Applied Markdown in comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Commit 4d320e30ee ("rust: platform: fix unrestricted &mut
platform::Device") changed the definition of platform::Device and
discarded the implicitly derived Send and Sync traits.
This isn't required by upstream code yet, and hence did not cause any
issues. However, it is relied on by upcoming drivers, hence add it back
in.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250318212940.137577-2-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 7b948a2af6 ("rust: pci: fix unrestricted &mut pci::Device")
changed the definition of pci::Device and discarded the implicitly
derived Send and Sync traits.
This isn't required by upstream code yet, and hence did not cause any
issues. However, it is relied on by upcoming drivers, hence add it back
in.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250318212940.137577-1-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When build the kernel using the llvm-18.1.3-rust-1.85.0-x86_64
with ARCH=arm64, the following symbols are generated:
$ nm vmlinux | grep ' _R'.*FileDescriptorReservation | rustfilt
... T <kernel::fs::file::FileDescriptorReservation>::fd_install
... T <kernel::fs::file::FileDescriptorReservation>::get_unused_fd_flags
... T <kernel::fs::file::FileDescriptorReservation as core::ops::drop::Drop>::drop
These Rust symbols are trivial wrappers around the C functions
fd_install, put_unused_fd and put_task_struct. It
doesn't make sense to go through a trivial wrapper for these
functions, so mark them inline.
Link: https://github.com/Rust-for-Linux/linux/issues/1145
Suggested-by: Alice Ryhl <aliceryhl@google.com>
Co-developed-by: Grace Deng <Grace.Deng006@Gmail.com>
Signed-off-by: Grace Deng <Grace.Deng006@Gmail.com>
Signed-off-by: Kunwu Chan <kunwu.chan@hotmail.com>
Link: https://lore.kernel.org/r/20250317023702.2360726-1-kunwu.chan@linux.dev
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
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>
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>
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>
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>
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>
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>
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>
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
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>
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>
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>
