Commit Graph
186 Commits
Author SHA1 Message Date
Kunwu ChanandBoqun Feng 11867144ff rust: sync: Mark PollCondVar::drop() inline
When building 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'.*PollCondVar  | rustfilt
... T <kernel::sync::poll::PollCondVar as kernel::init::PinnedDrop>::drop
...

This Rust symbol is trivial wrappers around the C functions
__wake_up_pollfree() and synchronize_rcu(). It doesn't make sense to go
through a trivial wrapper for its functions, so mark it inline.

[boqun: Reword the commit title and re-format the commit log per tip
tree's requirement, remove unnecessary information from "nm vmlinux"
result.]

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>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250317025205.2366518-1-kunwu.chan@linux.dev
2025-06-24 10:23:48 -07:00
Kunwu ChanandBoqun Feng 3f9ebeba98 rust: sync: Mark CondVar::notify_*() inline
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'.*CondVar | rustfilt
... T <kernel::sync::condvar::CondVar>::notify_all
... T <kernel::sync::condvar::CondVar>::notify_one
... T <kernel::sync::condvar::CondVar>::notify_sync
...

These notify_*() symbols are trivial wrappers around the C functions
__wake_up() and __wake_up_sync(). It doesn't make sense to go through
a trivial wrapper for these functions, so mark them inline.

[boqun: Reword the commit title for consistency and reformat the commit
log.]

Suggested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://github.com/Rust-for-Linux/linux/issues/1145
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>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250324061835.1693125-1-kunwu.chan@linux.dev
2025-06-24 10:23:48 -07:00
Tamir DubersteinandMiguel Ojeda fcad9bbf9e rust: enable clippy::ptr_as_ptr lint
In Rust 1.51.0, Clippy introduced the `ptr_as_ptr` lint [1]:

> Though `as` casts between raw pointers are not terrible,
> `pointer::cast` is safer because it cannot accidentally change the
> pointer's mutability, nor cast the pointer to other types like `usize`.

There are a few classes of changes required:
- Modules generated by bindgen are marked
  `#[allow(clippy::ptr_as_ptr)]`.
- Inferred casts (` as _`) are replaced with `.cast()`.
- Ascribed casts (` as *... T`) are replaced with `.cast::<T>()`.
- Multistep casts from references (` as *const _ as *const T`) are
  replaced with `core::ptr::from_ref(&x).cast()` with or without `::<T>`
  according to the previous rules. The `core::ptr::from_ref` call is
  required because `(x as *const _).cast::<T>()` results in inference
  failure.
- Native literal C strings are replaced with `c_str!().as_char_ptr()`.
- `*mut *mut T as _` is replaced with `let *mut *const T = (*mut *mut
  T)`.cast();` since pointer to pointer can be confusing.

Apply these changes and enable the lint -- no functional change
intended.

Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_as_ptr [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-1-f43b024581e8@gmail.com
[ Added `.cast()` for `opp`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-06-22 23:08:42 +02:00
Danilo Krummrich 1b56e765bf rust: completion: implement initial abstraction
Implement a minimal abstraction for the completion synchronization
primitive.

This initial abstraction only adds complete_all() and
wait_for_completion(), since that is what is required for the subsequent
Devres patch.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250612121817.1621-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-13 23:46:56 +02:00
Linus Torvalds ec7714e494 Merge tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - KUnit '#[test]'s:

      - Support KUnit-mapped 'assert!' macros.

        The support that landed last cycle was very basic, and the
        'assert!' macros panicked since they were the standard library
        ones. Now, they are mapped to the KUnit ones in a similar way to
        how is done for doctests, reusing the infrastructure there.

        With this, a failing test like:

            #[test]
            fn my_first_test() {
                assert_eq!(42, 43);
            }

        will report:

            # my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251
            Expected 42 == 43 to be true, but is false
            # my_first_test.speed: normal
            not ok 1 my_first_test

      - Support tests with checked 'Result' return types.

        The return value of test functions that return a 'Result' will
        be checked, thus one can now easily catch errors when e.g. using
        the '?' operator in tests.

        With this, a failing test like:

            #[test]
            fn my_test() -> Result {
                f()?;
                Ok(())
            }

        will report:

            # my_test: ASSERTION FAILED at rust/kernel/lib.rs:321
            Expected is_test_result_ok(my_test()) to be true, but is false
            # my_test.speed: normal
            not ok 1 my_test

      - Add 'kunit_tests' to the prelude.

   - Clarify the remaining language unstable features in use.

   - Compile 'core' with edition 2024 for Rust >= 1.87.

   - Workaround 'bindgen' issue with forward references to 'enum' types.

   - objtool: relax slice condition to cover more 'noreturn' functions.

   - Use absolute paths in macros referencing 'core' and 'kernel'
     crates.

   - Skip '-mno-fdpic' flag for bindgen in GCC 32-bit arm builds.

   - Clean some 'doc_markdown' lint hits -- we may enable it later on.

  'kernel' crate:

   - 'alloc' module:

      - 'Box': support for type coercion, e.g. 'Box<T>' to 'Box<dyn U>'
        if 'T' implements 'U'.

      - 'Vec': implement new methods (prerequisites for nova-core and
        binder): 'truncate', 'resize', 'clear', 'pop',
        'push_within_capacity' (with new error type 'PushError'),
        'drain_all', 'retain', 'remove' (with new error type
        'RemoveError'), insert_within_capacity' (with new error type
        'InsertError').

        In addition, simplify 'push' using 'spare_capacity_mut', split
        'set_len' into 'inc_len' and 'dec_len', add type invariant 'len
        <= capacity' and simplify 'truncate' using 'dec_len'.

   - 'time' module:

      - Morph the Rust hrtimer subsystem into the Rust timekeeping
        subsystem, covering delay, sleep, timekeeping, timers. This new
        subsystem has all the relevant timekeeping C maintainers listed
        in the entry.

      - Replace 'Ktime' with 'Delta' and 'Instant' types to represent a
        duration of time and a point in time.

      - Temporarily add 'Ktime' to 'hrtimer' module to allow 'hrtimer'
        to delay converting to 'Instant' and 'Delta'.

   - 'xarray' module:

      - Add a Rust abstraction for the 'xarray' data structure. This
        abstraction allows Rust code to leverage the 'xarray' to store
        types that implement 'ForeignOwnable'. This support is a
        dependency for memory backing feature of the Rust null block
        driver, which is waiting to be merged.

      - Set up an entry in 'MAINTAINERS' for the XArray Rust support.
        Patches will go to the new Rust XArray tree and then via the
        Rust subsystem tree for now.

      - Allow 'ForeignOwnable' to carry information about the pointed-to
        type. This helps asserting alignment requirements for the
        pointer passed to the foreign language.

   - 'container_of!': retain pointer mut-ness and add a compile-time
     check of the type of the first parameter ('$field_ptr').

   - Support optional message in 'static_assert!'.

   - Add C FFI types (e.g. 'c_int') to the prelude.

   - 'str' module: simplify KUnit tests 'format!' macro, convert
     'rusttest' tests into KUnit, take advantage of the '-> Result'
     support in KUnit '#[test]'s.

   - 'list' module: add examples for 'List', fix path of
     'assert_pinned!' (so far unused macro rule).

   - 'workqueue' module: remove 'HasWork::OFFSET'.

   - 'page' module: add 'inline' attribute.

  'macros' crate:

   - 'module' macro: place 'cleanup_module()' in '.exit.text' section.

  'pin-init' crate:

   - Add 'Wrapper<T>' trait for creating pin-initializers for wrapper
     structs with a structurally pinned value such as 'UnsafeCell<T>' or
     'MaybeUninit<T>'.

   - Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but
     not error if not all fields implement it. This is needed to derive
     'Zeroable' for all bindgen-generated structs.

   - Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the
     initialized type of an initializer. These are utilized by the
     'Wrapper<T>' implementations.

   - Add support for visibility in 'Zeroable' derive macro.

   - Add support for 'union's in 'Zeroable' derive macro.

   - Upstream dev news: streamline CI, fix some bugs. Add new workflows
     to check if the user-space version and the one in the kernel tree
     have diverged. Use the issues tab [1] to track them, which should
     help folks report and diagnose issues w.r.t. 'pin-init' better.

       [1] https://github.com/rust-for-linux/pin-init/issues

  Documentation:

   - Testing: add docs on the new KUnit '#[test]' tests.

   - Coding guidelines: explain that '///' vs. '//' applies to private
     items too. Add section on C FFI types.

   - Quick Start guide: update Ubuntu instructions and split them into
     "25.04" and "24.04 LTS and older".

  And a few other cleanups and improvements"

* tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (78 commits)
  rust: list: Fix typo `much` in arc.rs
  rust: check type of `$ptr` in `container_of!`
  rust: workqueue: remove HasWork::OFFSET
  rust: retain pointer mut-ness in `container_of!`
  Documentation: rust: testing: add docs on the new KUnit `#[test]` tests
  Documentation: rust: rename `#[test]`s to "`rusttest` host tests"
  rust: str: take advantage of the `-> Result` support in KUnit `#[test]`'s
  rust: str: simplify KUnit tests `format!` macro
  rust: str: convert `rusttest` tests into KUnit
  rust: add `kunit_tests` to the prelude
  rust: kunit: support checked `-> Result`s in KUnit `#[test]`s
  rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s
  rust: make section names plural
  rust: list: fix path of `assert_pinned!`
  rust: compile libcore with edition 2024 for 1.87+
  rust: dma: add missing Markdown code span
  rust: task: add missing Markdown code spans and intra-doc links
  rust: pci: fix docs related to missing Markdown code spans
  rust: alloc: add missing Markdown code span
  rust: alloc: add missing Markdown code spans
  ...
2025-06-04 21:18:37 -07:00
Patrick MillerandMiguel Ojeda 4bf7b97eb3 rust: make section names plural
Clean Rust documentation section headers to use plural names.

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1110
Signed-off-by: Patrick Miller <paddymills@proton.me>
Link: https://lore.kernel.org/r/20241002022749.390836-1-paddymills@proton.me
[ Removed the `init` one that doesn't apply anymore and
  reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-26 18:03:09 +02:00
Miguel Ojeda 06ff274f25 Merge tag 'rust-xarray-for-v6.16' of https://github.com/Rust-for-Linux/linux into rust-next
Pull XArray updates from Andreas Hindborg:
 "Introduce Rust support for the 'xarray' data structure:

   - Add a Rust abstraction for the 'xarray' data structure. This
     abstraction allows Rust code to leverage the 'xarray' to store
     types that implement 'ForeignOwnable'. This support is a dependency
     for memory backing feature of the Rust null block driver, which is
     waiting to be merged.

   - Set up an entry in MAINTAINERS for the XArray Rust support. Patches
     will go to the new Rust XArray tree and then via the Rust subsystem
     tree for now.

  'kernel' crate:

   - Allow 'ForeignOwnable' to carry information about the pointed-to
     type. This helps asserting alignment requirements for the pointer
     passed to the foreign language."

* tag 'rust-xarray-for-v6.16' of https://github.com/Rust-for-Linux/linux:
  MAINTAINERS: add entry for Rust XArray API
  rust: xarray: Add an abstraction for XArray
  rust: types: add `ForeignOwnable::PointedTo`
2025-05-18 20:36:56 +02:00
I Hsin ChengandJoel Fernandes 9520371e3d rust: sync: rcu: Mark Guard methods as inline
Currently the implementation of "Guard" methods are basically wrappers
around rcu's function within kernel. Building the kernel with llvm
18.1.8 on x86_64 machine will generate the following symbols:

$ nm vmlinux | grep ' _R'.*Guard | rustfilt
ffffffff817b6c90 T <kernel::sync::rcu::Guard>::new
ffffffff817b6cb0 T <kernel::sync::rcu::Guard>::unlock
ffffffff817b6cd0 T <kernel::sync::rcu::Guard as core::ops::drop::Drop>::drop
ffffffff817b6c90 T <kernel::sync::rcu::Guard as core::default::Default>::default

These Rust symbols are basically wrappers around functions
"rcu_read_lock" and "rcu_read_unlock". Marking them as inline can
reduce the generation of these symbols, and saves the size of code
generation for 132 bytes.

$ ./scripts/bloat-o-meter vmlinux_old vmlinux_new
(Output is demangled for readability)

add/remove: 0/10 grow/shrink: 0/1 up/down: 0/-132 (-132)
Function                                     old     new   delta
rust_driver_pci::SampleDriver::probe        1041    1034      -7
kernel::sync::rcu::Guard::default             9       -      -9
kernel::sync::rcu::Guard::drop                9       -      -9
kernel::sync::rcu::read_lock                  9       -      -9
kernel::sync::rcu::Guard::unlock              9       -      -9
kernel::sync::rcu::Guard::new                 9       -      -9
__pfx__kernel::sync::rcu::Guard::default     16       -     -16
__pfx__kernel::sync::rcu::Guard::drop        16       -     -16
__pfx__kernel::sync::rcu::read_lock          16       -     -16
__pfx__kernel::sync::rcu::Guard::unlock      16       -     -16
__pfx__kernel::sync::rcu::Guard::new         16       -     -16
Total: Before=23365955, After=23365823, chg -0.00%

Link: https://github.com/Rust-for-Linux/linux/issues/1145
Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Charalampos Mitrodimas <charmitro@posteo.net>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
2025-05-16 09:00:54 -04:00
Xizhe YinandMiguel Ojeda 86d990c7b6 rust: convert raw URLs to Markdown autolinks in comments
Some comments in Rust files use raw URLs (http://example.com) rather
than Markdown autolinks <URL>. This inconsistency makes the
documentation less uniform and harder to maintain.

This patch converts all remaining raw URLs in Rust code comments to use
the Markdown autolink format, maintaining consistency with the rest of
the codebase which already uses this style.

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1153
Signed-off-by: Xizhe Yin <xizheyin@smail.nju.edu.cn>
Link: https://lore.kernel.org/r/509F0B66E3C1575D+20250407033441.5567-1-xizheyin@smail.nju.edu.cn
[ Used From form for Signed-off-by. Sorted tags. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-12 00:20:25 +02:00
Tamir DubersteinandAndreas Hindborg 1a4736c3d8 rust: types: add ForeignOwnable::PointedTo
Allow implementors to specify the foreign pointer type; this exposes
information about the pointed-to type such as its alignment.

This requires the trait to be `unsafe` since it is now possible for
implementors to break soundness by returning a misaligned pointer.

Encoding the pointer type in the trait (and avoiding pointer casts)
allows the compiler to check that implementors return the correct
pointer type. This is preferable to directly encoding the alignment in
the trait using a constant as the compiler would be unable to check it.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250423-rust-xarray-bindings-v19-1-83cdcf11c114@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-05-01 11:35:49 +02:00
Linus Torvalds 4e82c87058 Merge tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Extract the 'pin-init' API from the 'kernel' crate and make it into
     a standalone crate.

     In order to do this, the contents are rearranged so that they can
     easily be kept in sync with the version maintained out-of-tree that
     other projects have started to use too (or plan to, like QEMU).

     This will reduce the maintenance burden for Benno, who will now
     have his own sub-tree, and will simplify future expected changes
     like the move to use 'syn' to simplify the implementation.

   - Add '#[test]'-like support based on KUnit.

     We already had doctests support based on KUnit, which takes the
     examples in our Rust documentation and runs them under KUnit.

     Now, we are adding the beginning of the support for "normal" tests,
     similar to those the '#[test]' tests in userspace Rust. For
     instance:

         #[kunit_tests(my_suite)]
         mod tests {
             #[test]
             fn my_test() {
                 assert_eq!(1 + 1, 2);
             }
         }

     Unlike with doctests, the 'assert*!'s do not map to the KUnit
     assertion APIs yet.

   - Check Rust signatures at compile time for functions called from C
     by name.

     In particular, introduce a new '#[export]' macro that can be placed
     in the Rust function definition. It will ensure that the function
     declaration on the C side matches the signature on the Rust
     function:

         #[export]
         pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize {
             // ...
         }

     The macro essentially forces the compiler to compare the types of
     the actual Rust function and the 'bindgen'-processed C signature.

     These cases are rare so far. In the future, we may consider
     introducing another tool, 'cbindgen', to generate C headers
     automatically. Even then, having these functions explicitly marked
     may be a good idea anyway.

   - Enable the 'raw_ref_op' Rust feature: it is already stable, and
     allows us to use the new '&raw' syntax, avoiding a couple macros.
     After everyone has migrated, we will disallow the macros.

   - Pass the correct target to 'bindgen' on Usermode Linux.

   - Fix 'rusttest' build in macOS.

  'kernel' crate:

   - New 'hrtimer' module: add support for setting up intrusive timers
     without allocating when starting the timer. Add support for
     'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer
     types for use with timer callbacks. Add support for setting clock
     source and timer mode.

   - New 'dma' module: add a simple DMA coherent allocator abstraction
     and a test sample driver.

   - 'list' module: make the linked list 'Cursor' point between
     elements, rather than at an element, which is more convenient to us
     and allows for cursors to empty lists; and document it with
     examples of how to perform common operations with the provided
     methods.

   - 'str' module: implement a few traits for 'BStr' as well as the
     'strip_prefix()' method.

   - 'sync' module: add 'Arc::as_ptr'.

   - 'alloc' module: add 'Box::into_pin'.

   - 'error' module: extend the 'Result' documentation, including a few
     examples on different ways of handling errors, a warning about
     using methods that may panic, and links to external documentation.

  'macros' crate:

   - 'module' macro: add the 'authors' key to support multiple authors.
     The original key will be kept until everyone has migrated.

  Documentation:

   - Add error handling sections.

  MAINTAINERS:

   - Add Danilo Krummrich as reviewer of the Rust "subsystem".

   - Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has
     its own sub-tree.

   - Add sub-tree for 'RUST [ALLOC]'.

   - Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with
     Abdiel Janulgue as primary maintainer. It will go through the
     sub-tree of the 'RUST [ALLOC]' entry.

   - Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as
     maintainer. It has its own sub-tree.

  And a few other cleanups and improvements"

* tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (71 commits)
  rust: dma: add `Send` implementation for `CoherentAllocation`
  rust: macros: fix `make rusttest` build on macOS
  rust: block: refactor to use `&raw mut`
  rust: enable `raw_ref_op` feature
  rust: uaccess: name the correct function
  rust: rbtree: fix comments referring to Box instead of KBox
  rust: hrtimer: add maintainer entry
  rust: hrtimer: add clocksource selection through `ClockId`
  rust: hrtimer: add `HrTimerMode`
  rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
  rust: alloc: add `Box::into_pin`
  rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
  rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
  rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
  rust: hrtimer: add `UnsafeHrTimerPointer`
  rust: hrtimer: allow timer restart from timer handler
  rust: str: implement `strip_prefix` for `BStr`
  rust: str: implement `AsRef<BStr>` for `[u8]` and `BStr`
  rust: str: implement `Index` for `BStr`
  rust: str: implement `PartialEq` for `BStr`
  ...
2025-03-30 17:03:26 -07:00
Miguel Ojeda e6ea10d5db Merge tag 'rust-hrtimer-for-v6.15-v3' of https://github.com/Rust-for-Linux/linux into rust-next
Pull rust-hrtimer updates from Andreas Hindborg:
 "Introduce Rust support for the 'hrtimer' subsystem:

   - Add a way to use the 'hrtimer' subsystem from Rust. Rust code can
     now set up intrusive timers without allocating when starting the
     timer.

   - Add support for 'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and
     'Pin<&mut _>' as pointer types for use with timer callbacks.

   - Add support for setting clock source and timer mode.

  'kernel' crate:

   - Add 'Arc::as_ptr' for converting an 'Arc' to a raw pointer. This is
     a dependency for the 'hrtimer' API.

   - Add 'Box::into_pin' for converting a 'Box<_>' into a 'Pin<Box<_>>'
     to align with Rust 'alloc'. This is a dependency for the 'hrtimer'
     API."

* tag 'rust-hrtimer-for-v6.15-v3' of https://github.com/Rust-for-Linux/linux:
  rust: hrtimer: add maintainer entry
  rust: hrtimer: add clocksource selection through `ClockId`
  rust: hrtimer: add `HrTimerMode`
  rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
  rust: alloc: add `Box::into_pin`
  rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
  rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
  rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
  rust: hrtimer: add `UnsafeHrTimerPointer`
  rust: hrtimer: allow timer restart from timer handler
  rust: hrtimer: implement `HrTimerPointer` for `Arc`
  rust: sync: add `Arc::as_ptr`
  rust: hrtimer: introduce hrtimer support
2025-03-25 23:41:14 +01:00
Linus Torvalds 23608993bb Merge tag 'locking-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "Locking primitives:
   - Micro-optimize percpu_{,try_}cmpxchg{64,128}_op() and
     {,try_}cmpxchg{64,128} on x86 (Uros Bizjak)
   - mutexes: extend debug checks in mutex_lock() (Yunhui Cui)
   - Misc cleanups (Uros Bizjak)

  Lockdep:
   - Fix might_fault() lockdep check of current->mm->mmap_lock (Peter
     Zijlstra)
   - Don't disable interrupts on RT in disable_irq_nosync_lockdep.*()
     (Sebastian Andrzej Siewior)
   - Disable KASAN instrumentation of lockdep.c (Waiman Long)
   - Add kasan_check_byte() check in lock_acquire() (Waiman Long)
   - Misc cleanups (Sebastian Andrzej Siewior)

  Rust runtime integration:
   - Use Pin for all LockClassKey usages (Mitchell Levy)
   - sync: Add accessor for the lock behind a given guard (Alice Ryhl)
   - sync: condvar: Add wait_interruptible_freezable() (Alice Ryhl)
   - sync: lock: Add an example for Guard:: Lock_ref() (Boqun Feng)

  Split-lock detection feature (x86):
   - Fix warning mode with disabled mitigation mode (Maksim Davydov)

  Locking events:
   - Add locking events for rtmutex slow paths (Waiman Long)
   - Add locking events for lockdep (Waiman Long)"

* tag 'locking-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Remove disable_irq_lockdep()
  lockdep: Don't disable interrupts on RT in disable_irq_nosync_lockdep.*()
  rust: lockdep: Use Pin for all LockClassKey usages
  rust: sync: condvar: Add wait_interruptible_freezable()
  rust: sync: lock: Add an example for Guard:: Lock_ref()
  rust: sync: Add accessor for the lock behind a given guard
  locking/lockdep: Add kasan_check_byte() check in lock_acquire()
  locking/lockdep: Disable KASAN instrumentation of lockdep.c
  locking/lock_events: Add locking events for lockdep
  locking/lock_events: Add locking events for rtmutex slow paths
  x86/split_lock: Fix the delayed detection logic
  lockdep/mm: Fix might_fault() lockdep check of current->mm->mmap_lock
  x86/locking: Remove semicolon from "lock" prefix
  locking/mutex: Add MUTEX_WARN_ON() into fast path
  x86/locking: Use asm_inline for {,try_}cmpxchg{64,128} emulations
  x86/locking: Use ALT_OUTPUT_SP() for percpu_{,try_}cmpxchg{64,128}_op()
2025-03-24 20:55:03 -07:00
Benno LossinandMiguel Ojeda 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 LossinandMiguel Ojeda 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 LossinandMiguel Ojeda 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
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
Borys TyranandMiguel Ojeda 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
Mitchell LevyandIngo Molnar 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 RyhlandIngo Molnar 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 FengandIngo Molnar 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 RyhlandIngo Molnar 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
Alban KurtiandMiguel Ojeda 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
Linus Torvalds 2ab002c755 Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and debugfs updates from Greg KH:
 "Here is the big set of driver core and debugfs updates for 6.14-rc1.

  Included in here is a bunch of driver core, PCI, OF, and platform rust
  bindings (all acked by the different subsystem maintainers), hence the
  merge conflict with the rust tree, and some driver core api updates to
  mark things as const, which will also require some fixups due to new
  stuff coming in through other trees in this merge window.

  There are also a bunch of debugfs updates from Al, and there is at
  least one user that does have a regression with these, but Al is
  working on tracking down the fix for it. In my use (and everyone
  else's linux-next use), it does not seem like a big issue at the
  moment.

  Here's a short list of the things in here:

   - driver core rust bindings for PCI, platform, OF, and some i/o
     functions.

     We are almost at the "write a real driver in rust" stage now,
     depending on what you want to do.

   - misc device rust bindings and a sample driver to show how to use
     them

   - debugfs cleanups in the fs as well as the users of the fs api for
     places where drivers got it wrong or were unnecessarily doing
     things in complex ways.

   - driver core const work, making more of the api take const * for
     different parameters to make the rust bindings easier overall.

   - other small fixes and updates

  All of these have been in linux-next with all of the aforementioned
  merge conflicts, and the one debugfs issue, which looks to be resolved
  "soon""

* tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
  rust: device: Use as_char_ptr() to avoid explicit cast
  rust: device: Replace CString with CStr in property_present()
  devcoredump: Constify 'struct bin_attribute'
  devcoredump: Define 'struct bin_attribute' through macro
  rust: device: Add property_present()
  saner replacement for debugfs_rename()
  orangefs-debugfs: don't mess with ->d_name
  octeontx2: don't mess with ->d_parent or ->d_parent->d_name
  arm_scmi: don't mess with ->d_parent->d_name
  slub: don't mess with ->d_name
  sof-client-ipc-flood-test: don't mess with ->d_name
  qat: don't mess with ->d_name
  xhci: don't mess with ->d_iname
  mtu3: don't mess wiht ->d_iname
  greybus/camera - stop messing with ->d_iname
  mediatek: stop messing with ->d_iname
  netdevsim: don't embed file_operations into your structs
  b43legacy: make use of debugfs_get_aux()
  b43: stop embedding struct file_operations into their objects
  carl9170: stop embedding file_operations into their objects
  ...
2025-01-28 12:25:12 -08:00
Linus Torvalds e3610441d1 Merge tag 'rust-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Finish the move to custom FFI integer types started in the previous
     cycle and finally map 'long' to 'isize' and 'char' to 'u8'. Do a
     few cleanups on top thanks to that.

   - Start to use 'derive(CoercePointee)' on Rust >= 1.84.0.

     This is a major milestone on the path to build the kernel using
     only stable Rust features. In particular, previously we were using
     the unstable features 'coerce_unsized', 'dispatch_from_dyn' and
     'unsize', and now we will use the new 'derive_coerce_pointee' one,
     which is on track to stabilization. This new feature is a macro
     that essentially expands into code that internally uses the
     unstable features that we were using before, without having to
     expose those.

     With it, stable Rust users, including the kernel, will be able to
     build custom smart pointers that work with trait objects, e.g.:

         fn f(p: &Arc<dyn Display>) {
             pr_info!("{p}\n");
         }

         let a: Arc<dyn Display> = Arc::new(42i32, GFP_KERNEL)?;
         let b: Arc<dyn Display> = Arc::new("hello there", GFP_KERNEL)?;

         f(&a); // Prints "42".
         f(&b); // Prints "hello there".

     Together with the 'arbitrary_self_types' feature that we started
     using in the previous cycle, using our custom smart pointers like
     'Arc' will eventually only rely in stable Rust.

   - Introduce 'PROCMACROLDFLAGS' environment variable to allow to link
     Rust proc macros using different flags than those used for linking
     Rust host programs (e.g. when 'rustc' uses a different C library
     than the host programs' one), which Android needs.

   - Help kernel builds under macOS with Rust enabled by accomodating
     other naming conventions for dynamic libraries (i.e. '.so' vs.
     '.dylib') which are used for Rust procedural macros. The actual
     support for macOS (i.e. the rest of the pieces needed) is provided
     out-of-tree by others, following the policy used for other parts of
     the kernel by Kbuild.

   - Run Clippy for 'rusttest' code too and clean the bits it spotted.

   - Provide Clippy with the minimum supported Rust version to improve
     the suggestions it gives.

   - Document 'bindgen' 0.71.0 regression.

  'kernel' crate:

   - 'build_error!': move users of the hidden function to the documented
     macro, prevent such uses in the future by moving the function
     elsewhere and add the macro to the prelude.

   - 'types' module: add improved version of 'ForeignOwnable::borrow_mut'
     (which was removed in the past since it was problematic); change
     'ForeignOwnable' pointer type to '*mut'.

   - 'alloc' module: implement 'Display' for 'Box' and align the 'Debug'
     implementation to it; add example (doctest) for 'ArrayLayout::new()'

   - 'sync' module: document 'PhantomData' in 'Arc'; use
     'NonNull::new_unchecked' in 'ForeignOwnable for Arc' impl.

   - 'uaccess' module: accept 'Vec's with different allocators in
     'UserSliceReader::read_all'.

   - 'workqueue' module: enable run-testing a couple more doctests.

   - 'error' module: simplify 'from_errno()'.

   - 'block' module: fix formatting in code documentation (a lint to catch
     these is being implemented).

   - Avoid 'unwrap()'s in doctests, which also improves the examples by
     showing how kernel code is supposed to be written.

   - Avoid 'as' casts with 'cast{,_mut}' calls which are a bit safer.

  And a few other cleanups"

* tag 'rust-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (32 commits)
  kbuild: rust: add PROCMACROLDFLAGS
  rust: uaccess: generalize userSliceReader to support any Vec
  rust: kernel: add improved version of `ForeignOwnable::borrow_mut`
  rust: kernel: reorder `ForeignOwnable` items
  rust: kernel: change `ForeignOwnable` pointer to mut
  rust: arc: split unsafe block, add missing comment
  rust: types: avoid `as` casts
  rust: arc: use `NonNull::new_unchecked`
  rust: use derive(CoercePointee) on rustc >= 1.84.0
  rust: alloc: add doctest for `ArrayLayout::new()`
  rust: init: update `stack_try_pin_init` examples
  rust: error: import `kernel`'s `LayoutError` instead of `core`'s
  rust: str: replace unwraps with question mark operators
  rust: page: remove unnecessary helper function from doctest
  rust: rbtree: remove unwrap in asserts
  rust: init: replace unwraps with question mark operators
  rust: use host dylib naming convention to support macOS
  rust: add `build_error!` to the prelude
  rust: kernel: move `build_error` hidden function to prevent mistakes
  rust: use the `build_error!` macro, not the hidden function
  ...
2025-01-21 17:48:03 -08:00