Commit graph

15 commits

Author SHA1 Message Date
Wedson Almeida Filho b6a006e21b rust: alloc: introduce allocation flags
We'll use them when allocating `Box`, `Arc`, and `UniqueArc` instances,
as well as when allocating memory for `Vec` elements. These changes will
come in subsequent patches.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-6-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:05:06 +02:00
Mika Westerberg 789809a3d5 rust: bindings: Order headers alphabetically
As the comment on top of the file suggests, sort the headers
alphabetically.

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://github.com/Rust-for-Linux/linux/issues/1002
Link: https://lore.kernel.org/r/20240216152723.993445-1-mika.westerberg@linux.intel.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-02-18 21:21:48 +01:00
Alice Ryhl 82e1708748 rust: time: add msecs to jiffies conversion
Defines type aliases and conversions for msecs and jiffies.

This is used by Rust Binder for process freezing. There, we want to
sleep until the freeze operation completes, but we want to be able to
abort the process freezing if it doesn't complete within some timeout.
The freeze timeout is supplied in msecs.

Note that we need to convert to jiffies in Binder. It is not enough to
introduce a variant of `CondVar::wait_timeout` that takes the timeout in
msecs because we need to be able to restart the sleep with the remaining
sleep duration if it is interrupted, and if the API takes msecs rather
than jiffies, then that would require a conversion roundtrip jiffies->
msecs->jiffies that is best avoided.

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Tiago Lam <tiagolam@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240108-rb-new-condvar-methods-v4-2-88e0c871cc05@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-01-28 19:50:48 +01:00
Linus Torvalds b6964fe239 Rust changes for v6.8
Another routine one in terms of features. In terms of lines, this time
 the 'alloc' version upgrade is less prominent, given that it was fairly
 small (and we did not have two upgrades).
 
 Toolchain and infrastructure:
 
  - Upgrade to Rust 1.74.1.
 
    The patch release includes a fix for an ICE that the Apple AGX GPU
    driver was hitting.
 
  - Support 'srctree'-relative links in Rust code documentation.
 
  - Automate part of the manual constants handling (i.e. the ones not
    recognised by 'bindgen').
 
  - Suppress searching builtin sysroot to avoid confusion with installed
    sysroots, needed for the to-be-merged arm64 support which uses
    a builtin target.
 
  - Ignore '__preserve_most' functions for 'bindgen'.
 
  - Reduce header inclusion bloat in exports.
 
 'kernel' crate:
 
  - Implement 'Debug' for 'CString'.
 
  - Make 'CondVar::wait()' an uninterruptible wait.
 
 'macros' crate:
 
  - Update 'paste!' to accept string literals.
 
  - Improve '#[vtable]' documentation.
 
 Documentation:
 
  - Add testing section (KUnit and 'rusttest' target).
 
  - Remove 'CC=clang' mentions.
 
  - Clarify that 'rustup override' applies to build directory.
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Merge tag 'rust-6.8' of https://github.com/Rust-for-Linux/linux

Pull Rust updates from Miguel Ojeda:
 "Another routine one in terms of features. In terms of lines, this time
  the 'alloc' version upgrade is less prominent, given that it was
  fairly small (and we did not have two upgrades)

  Toolchain and infrastructure:

   - Upgrade to Rust 1.74.1

     The patch release includes a fix for an ICE that the Apple AGX GPU
     driver was hitting

   - Support 'srctree'-relative links in Rust code documentation

   - Automate part of the manual constants handling (i.e. the ones not
     recognised by 'bindgen')

   - Suppress searching builtin sysroot to avoid confusion with
     installed sysroots, needed for the to-be-merged arm64 support which
     uses a builtin target

   - Ignore '__preserve_most' functions for 'bindgen'

   - Reduce header inclusion bloat in exports

  'kernel' crate:

   - Implement 'Debug' for 'CString'

   - Make 'CondVar::wait()' an uninterruptible wait

  'macros' crate:

   - Update 'paste!' to accept string literals

   - Improve '#[vtable]' documentation

  Documentation:

   - Add testing section (KUnit and 'rusttest' target)

   - Remove 'CC=clang' mentions

   - Clarify that 'rustup override' applies to build directory"

* tag 'rust-6.8' of https://github.com/Rust-for-Linux/linux:
  docs: rust: Clarify that 'rustup override' applies to build directory
  docs: rust: Add rusttest info
  docs: rust: remove `CC=clang` mentions
  rust: support `srctree`-relative links
  rust: sync: Makes `CondVar::wait()` an uninterruptible wait
  rust: upgrade to Rust 1.74.1
  rust: Suppress searching builtin sysroot
  rust: macros: improve `#[vtable]` documentation
  rust: macros: update 'paste!' macro to accept string literals
  rust: bindings: rename const binding using sed
  rust: Ignore preserve-most functions
  rust: replace <linux/module.h> with <linux/export.h> in rust/exports.c
  rust: kernel: str: Implement Debug for CString
2024-01-11 13:05:41 -08:00
FUJITA Tomonori f20fd5449a rust: core abstractions for network PHY drivers
This patch adds abstractions to implement network PHY drivers; the
driver registration and bindings for some of callback functions in
struct phy_driver and many genphy_ functions.

This feature is enabled with CONFIG_RUST_PHYLIB_ABSTRACTIONS=y.

This patch enables unstable const_maybe_uninit_zeroed feature for
kernel crate to enable unsafe code to handle a constant value with
uninitialized data. With the feature, the abstractions can initialize
a phy_driver structure with zero easily; instead of initializing all
the members by hand. It's supposed to be stable in the not so distant
future.

Link: https://github.com/rust-lang/rust/pull/116218

Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-15 09:35:50 +00:00
Gary Guo 743766565d rust: bindings: rename const binding using sed
Currently, for `const`s that bindgen doesn't recognise, we define a
helper constant with

    const <TYPE> BINDINGS_<NAME> = <NAME>;

in `bindings_helper.h` and then we put

    pub const <NAME>: <TYPE> = BINDINGS_<NAME>;

in `bindings/lib.rs`. This is fine since we currently only have 3
constants that are defined this way, but is going to be more annoying
when more constants are added since every new constant needs to be
defined in two places.

This patch changes the way we define constant helpers to

    const <TYPE> RUST_CONST_HELPER_<NAME> = <NAME>;

and then use `sed` to postprocess Rust code generated by bindgen to
remove the distinct prefix, so users of the `bindings` crate can refer
to the name directly.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20231104145700.2495176-1-gary@garyguo.net
[ Reworded for typos. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-14 20:14:01 +01:00
Alice Ryhl d4d791d4aa rust: workqueue: add low-level workqueue bindings
Define basic low-level bindings to a kernel workqueue. The API defined
here can only be used unsafely. Later commits will provide safe
wrappers.

Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25 09:46:42 -10:00
Linus Torvalds 815c24a085 linux-kselftest-kunit-6.6-rc1
This kunit update for Linux 6.6.rc1 consists of:
 
 -- Adds support for running Rust documentation tests as KUnit tests
 -- Makes init, str, sync, types doctests compilable/testable
 -- Adds support for attributes API which include speed, modules
    attributes, ability to filter and report attributes.
 -- Adds support for marking tests slow using attributes API.
 -- Adds attributes API documentation
 -- Fixes to wild-memory-access bug in kunit_filter_suites() and
    a possible memory leak in kunit_filter_suites()
 -- Adds support for counting number of test suites in a module, list
    action to kunit test modules, and test filtering on module tests.
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Merge tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kunit updates from Shuah Khan:

 - add support for running Rust documentation tests as KUnit tests

 - make init, str, sync, types doctests compilable/testable

 - add support for attributes API which include speed, modules
   attributes, ability to filter and report attributes

 - add support for marking tests slow using attributes API

 - add attributes API documentation

 - fix a wild-memory-access bug in kunit_filter_suites() and a possible
   memory leak in kunit_filter_suites()

 - add support for counting number of test suites in a module, list
   action to kunit test modules, and test filtering on module tests

* tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits)
  kunit: fix struct kunit_attr header
  kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT
  kunit: Allow kunit test modules to use test filtering
  kunit: Make 'list' action available to kunit test modules
  kunit: Report the count of test suites in a module
  kunit: fix uninitialized variables bug in attributes filtering
  kunit: fix possible memory leak in kunit_filter_suites()
  kunit: fix wild-memory-access bug in kunit_filter_suites()
  kunit: Add documentation of KUnit test attributes
  kunit: add tests for filtering attributes
  kunit: time: Mark test as slow using test attributes
  kunit: memcpy: Mark tests as slow using test attributes
  kunit: tool: Add command line interface to filter and report attributes
  kunit: Add ability to filter attributes
  kunit: Add module attribute
  kunit: Add speed attribute
  kunit: Add test attributes API structure
  MAINTAINERS: add Rust KUnit files to the KUnit entry
  rust: support running Rust documentation tests as KUnit ones
  rust: types: make doctests compilable/testable
  ...
2023-08-28 18:56:38 -07:00
Boqun Feng b3d8aa84bb rust: allocator: Prevent mis-aligned allocation
Currently the rust allocator simply passes the size of the type Layout
to krealloc(), and in theory the alignment requirement from the type
Layout may be larger than the guarantee provided by SLAB, which means
the allocated object is mis-aligned.

Fix this by adjusting the allocation size to the nearest power of two,
which SLAB always guarantees a size-aligned allocation. And because Rust
guarantees that the original size must be a multiple of alignment and
the alignment must be a power of two, then the alignment requirement is
satisfied.

Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Co-developed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Signed-off-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Cc: stable@vger.kernel.org # v6.1+
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 247b365dc8 ("rust: add `kernel` crate")
Link: https://github.com/Rust-for-Linux/linux/issues/974
Link: https://lore.kernel.org/r/20230730012905.643822-2-boqun.feng@gmail.com
[ Applied rewording of comment as discussed in the mailing list. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-04 17:10:31 +02:00
Miguel Ojeda a66d733da8 rust: support running Rust documentation tests as KUnit ones
Rust has documentation tests: these are typically examples of
usage of any item (e.g. function, struct, module...).

They are very convenient because they are just written
alongside the documentation. For instance:

    /// Sums two numbers.
    ///
    /// ```
    /// assert_eq!(mymod::f(10, 20), 30);
    /// ```
    pub fn f(a: i32, b: i32) -> i32 {
        a + b
    }

In userspace, the tests are collected and run via `rustdoc`.
Using the tool as-is would be useful already, since it allows
to compile-test most tests (thus enforcing they are kept
in sync with the code they document) and run those that do not
depend on in-kernel APIs.

However, by transforming the tests into a KUnit test suite,
they can also be run inside the kernel. Moreover, the tests
get to be compiled as other Rust kernel objects instead of
targeting userspace.

On top of that, the integration with KUnit means the Rust
support gets to reuse the existing testing facilities. For
instance, the kernel log would look like:

    KTAP version 1
    1..1
        KTAP version 1
        # Subtest: rust_doctests_kernel
        1..59
        # rust_doctest_kernel_build_assert_rs_0.location: rust/kernel/build_assert.rs:13
        ok 1 rust_doctest_kernel_build_assert_rs_0
        # rust_doctest_kernel_build_assert_rs_1.location: rust/kernel/build_assert.rs:56
        ok 2 rust_doctest_kernel_build_assert_rs_1
        # rust_doctest_kernel_init_rs_0.location: rust/kernel/init.rs:122
        ok 3 rust_doctest_kernel_init_rs_0
        ...
        # rust_doctest_kernel_types_rs_2.location: rust/kernel/types.rs:150
        ok 59 rust_doctest_kernel_types_rs_2
    # rust_doctests_kernel: pass:59 fail:0 skip:0 total:59
    # Totals: pass:59 fail:0 skip:0 total:59
    ok 1 rust_doctests_kernel

Therefore, add support for running Rust documentation tests
in KUnit. Some other notes about the current implementation
and support follow.

The transformation is performed by a couple scripts written
as Rust hostprogs.

Tests using the `?` operator are also supported as usual, e.g.:

    /// ```
    /// # use kernel::{spawn_work_item, workqueue};
    /// spawn_work_item!(workqueue::system(), || pr_info!("x"))?;
    /// # Ok::<(), Error>(())
    /// ```

The tests are also compiled with Clippy under `CLIPPY=1`, just
like normal code, thus also benefitting from extra linting.

The names of the tests are currently automatically generated.
This allows to reduce the burden for documentation writers,
while keeping them fairly stable for bisection. This is an
improvement over the `rustdoc`-generated names, which include
the line number; but ideally we would like to get `rustdoc` to
provide the Rust item path and a number (for multiple examples
in a single documented Rust item).

In order for developers to easily see from which original line
a failed doctests came from, a KTAP diagnostic line is printed
to the log, containing the location (file and line) of the
original test (i.e. instead of the location in the generated
Rust file):

    # rust_doctest_kernel_types_rs_2.location: rust/kernel/types.rs:150

This line follows the syntax for declaring test metadata in the
proposed KTAP v2 spec [1], which may be used for the proposed
KUnit test attributes API [2]. Thus hopefully this will make
migration easier later on (suggested by David [3]).

The original line in that test attribute is figured out by
providing an anchor (suggested by Boqun [4]). The original file
is found by walking the filesystem, checking directory prefixes
to reduce the amount of combinations to check, and it is only
done once per file. Ambiguities are detected and reported.

A notable difference from KUnit C tests is that the Rust tests
appear to assert using the usual `assert!` and `assert_eq!`
macros from the Rust standard library (`core`). We provide
a custom version that forwards the call to KUnit instead.
Importantly, these macros do not require passing context,
unlike the KUnit C ones (i.e. `struct kunit *`). This makes
them easier to use, and readers of the documentation do not need
to care about which testing framework is used. In addition, it
may allow us to test third-party code more easily in the future.

However, a current limitation is that KUnit does not support
assertions in other tasks. Thus we presently simply print an
error to the kernel log if an assertion actually failed. This
should be revisited to properly fail the test, perhaps saving
the context somewhere else, or letting KUnit handle it.

Link: https://lore.kernel.org/lkml/20230420205734.1288498-1-rmoar@google.com/ [1]
Link: https://lore.kernel.org/linux-kselftest/20230707210947.1208717-1-rmoar@google.com/ [2]
Link: https://lore.kernel.org/rust-for-linux/CABVgOSkOLO-8v6kdAGpmYnZUb+LKOX0CtYCo-Bge7r_2YTuXDQ@mail.gmail.com/ [3]
Link: https://lore.kernel.org/rust-for-linux/ZIps86MbJF%2FiGIzd@boqun-archlinux/ [4]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-07-19 09:32:53 -06:00
Gary Guo d2e3115d71 rust: error: impl Debug for Error with errname() integration
Integrate the `Error` type with `errname()` by providing a new
`name()` method.

Then, implement `Debug` for the type using the new method.

[ Miguel: under `CONFIG_SYMBOLIC_ERRNAME=n`, `errname()` is a
  `static inline`, so added a helper to support that case,
  like we had in the `rust` branch. Also moved `#include` up
  and reworded commit message for clarity. ]

Co-developed-by: Wedson Almeida Filho <walmeida@microsoft.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://lore.kernel.org/r/20230531174450.3733220-1-aliceryhl@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-06-13 01:24:42 +02:00
Wedson Almeida Filho 19096bce81 rust: sync: introduce CondVar
This is the traditional condition variable or monitor synchronisation
primitive. It is implemented with C's `wait_queue_head_t`.

It allows users to release a lock and go to sleep while guaranteeing
that notifications won't be missed. This is achieved by enqueuing a wait
entry before releasing the lock.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20230411054543.21278-12-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-22 01:46:45 +02:00
Wedson Almeida Filho 313c4281bc rust: add basic Task
It is an abstraction for C's `struct task_struct`. It implements
`AlwaysRefCounted`, so the refcount of the wrapped object is managed
safely on the Rust side.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20230411054543.21278-9-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-22 00:20:00 +02:00
Wedson Almeida Filho 9dc0436550 rust: sync: add Arc for ref-counted allocations
This is a basic implementation of `Arc` backed by C's `refcount_t`. It
allows Rust code to idiomatically allocate memory that is ref-counted.

Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-01-16 22:20:03 +01:00
Miguel Ojeda 8326ac05ee rust: add bindings crate
This crate contains the bindings to the C side of the kernel.

Calling C (in general, FFI) is assumed to be unsafe in Rust
and, in many cases, this is accurate. For instance, virtually
all C functions that take a pointer are unsafe since, typically,
it will be dereferenced at some point (and in most cases there
is no way for the callee to check its validity beforehand).

Since one of the goals of using Rust in the kernel is precisely
to avoid unsafe code in "leaf" kernel modules (e.g. drivers),
these bindings should not be used directly by them.

Instead, these bindings need to be wrapped into safe abstractions.
These abstractions provide a safe API that kernel modules can use.
In this way, unsafe code in kernel modules is minimized.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Maciej Falkowski <m.falkowski@samsung.com>
Signed-off-by: Maciej Falkowski <m.falkowski@samsung.com>
Co-developed-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-09-28 08:58:00 +02:00