Commit graph

27 commits

Author SHA1 Message Date
Linus Torvalds
352af6a011 Rust changes for v6.17
Toolchain and infrastructure:
 
  - Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness',
    'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and 'ref_as_ptr'.
 
    These are intended to avoid type casts with the 'as' operator, which
    are quite powerful, into restricted variants that are less powerful
    and thus should help to avoid mistakes.
 
  - Remove the 'author' key now that most instances were moved to the
    plural one in the previous cycle.
 
 'kernel' crate:
 
  - New 'bug' module: add 'warn_on!' macro which reuses the existing
    'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and
    kernel parameters:
 
        warn_on!(value == 42);
 
    To avoid duplicating the assembly code, the same strategy is followed
    as for the static branch code in order to share the assembly between
    both C and Rust. This required a few rearrangements on C arch headers
    -- the existing C macros should still generate the same outputs, thus
    no functional change expected there.
 
  - 'workqueue' module: add delayed work items, including a 'DelayedWork'
    struct, a 'impl_has_delayed_work!' macro and an 'enqueue_delayed'
    method, e.g.:
 
        /// Enqueue the struct for execution on the system workqueue,
        /// where its value will be printed 42 jiffies later.
        fn print_later(value: Arc<MyStruct>) {
            let _ = workqueue::system().enqueue_delayed(value, 42);
        }
 
  - New 'bits' module: add support for 'bit' and 'genmask' functions,
    with runtime- and compile-time variants, e.g.:
 
        static_assert!(0b00010000 == bit_u8(4));
        static_assert!(0b00011110 == genmask_u8(1..=4));
 
        assert!(checked_bit_u32(u32::BITS).is_none());
 
  - 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which reads
    NUL-terminated strings from userspace into a '&CStr'.
 
    Introduce 'UserPtr' newtype, similar in purpose to '__user' in C, to
    minimize mistakes handling userspace pointers, including mixing them
    up with integers and leaking them via the 'Debug' trait. Add it to
    the prelude, too.
 
  - Start preparations for the replacement of our custom 'CStr' type
    with the analogous type in the 'core' standard library. This will
    take place across several cycles to make it easier. For this one,
    it includes a new 'fmt' module, using upstream method names and some
    other cleanups.
 
    Replace 'fmt!' with a re-export, which helps Clippy lint properly,
    and clean up the found 'uninlined-format-args' instances.
 
  - 'dma' module:
 
    - Clarify wording and be consistent in 'coherent' nomenclature.
 
    - Convert the 'read!()' and 'write!()' macros to return a 'Result'.
 
    - Add 'as_slice()', 'write()' methods in 'CoherentAllocation'.
 
    - Expose 'count()' and 'size()' in 'CoherentAllocation' and add the
      corresponding type invariants.
 
    - Implement 'CoherentAllocation::dma_handle_with_offset()'.
 
  - 'time' module:
 
    - Make 'Instant' generic over clock source. This allows the compiler
      to assert that arithmetic expressions involving the 'Instant' use
      'Instants' based on the same clock source.
 
    - Make 'HrTimer' generic over the timer mode. 'HrTimer' timers take a
      'Duration' or an 'Instant' when setting the expiry time, depending
      on the timer mode. With this change, the compiler can check the
      type matches the timer mode.
 
    - Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep
      function that will select an appropriate sleep method depending on
      the requested sleep time.
 
    - Avoid 64-bit divisions on 32-bit hardware when calculating
      timestamps.
 
    - Seal the 'HrTimerMode' trait. This prevents users of the
      'HrTimerMode' from implementing the trait on their own types.
 
    - Pass the correct timer mode ID to 'hrtimer_start_range_ns()'.
 
  - 'list' module: remove 'OFFSET' constants, allowing to remove pointer
    arithmetic; now 'impl_list_item!' invokes 'impl_has_list_links!' or
    'impl_has_list_links_self_ptr!'. Other simplifications too.
 
  - 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a
    constant, which avoids exposing the type of the opaque pointer, and
    require 'into_foreign' to return non-null.
 
    Remove the 'Either<L, R>' type as well. It is unused, and we want to
    encourage the use of custom enums for concrete use cases.
 
  - 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types
    to allow them to be used in generic APIs.
 
  - 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box<T, A>';
     and 'Borrow', 'BorrowMut' and 'Default' for 'Vec<T, A>'.
 
  - 'Opaque' type: add 'cast_from' method to perform a restricted cast
    that cannot change the inner type and use it in callers of
    'container_of!'. Rename 'raw_get' to 'cast_into' to match it.
 
  - 'rbtree' module: add 'is_empty' method.
 
  - 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and
    'ARef', which are moved from the too general 'types' module which we
    want to reduce or eventually remove. Also fix a safety comment in
    'static_lock_class'.
 
 'pin-init' crate:
 
  - Add 'impl<T, E> [Pin]Init<T, E> for Result<T, E>', so results are now
    (pin-)initializers.
 
  - Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()'.
 
  - New 'zeroed()', a safe version of 'mem::zeroed()' and also provide
    it via 'Zeroable::zeroed()'.
 
  - Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for
    'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for '"Rust"'
    and '"C"' ABIs and up to 20 arguments.
 
  - Changed blanket impls of 'Init' and 'PinInit' from 'impl<T, E>
    [Pin]Init<T, E> for T' to 'impl<T> [Pin]Init<T> for T'.
 
  - Renamed 'zeroed()' to 'init_zeroed()'.
 
  - Upstream dev news: improve CI more to deny warnings, use
    '--all-targets'. Check the synchronization status of the two '-next'
    branches in upstream and the kernel.
 
 MAINTAINERS:
 
  - Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo
    Stoakes as reviewers (thanks everyone).
 
 And a few other cleanups and improvements.
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Merge tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness',
     'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and
     'ref_as_ptr'

     These are intended to avoid type casts with the 'as' operator,
     which are quite powerful, into restricted variants that are less
     powerful and thus should help to avoid mistakes

   - Remove the 'author' key now that most instances were moved to the
     plural one in the previous cycle

  'kernel' crate:

   - New 'bug' module: add 'warn_on!' macro which reuses the existing
     'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and
     kernel parameters:

         warn_on!(value == 42);

     To avoid duplicating the assembly code, the same strategy is
     followed as for the static branch code in order to share the
     assembly between both C and Rust

     This required a few rearrangements on C arch headers -- the
     existing C macros should still generate the same outputs, thus no
     functional change expected there

   - 'workqueue' module: add delayed work items, including a
     'DelayedWork' struct, a 'impl_has_delayed_work!' macro and an
     'enqueue_delayed' method, e.g.:

         /// Enqueue the struct for execution on the system workqueue,
         /// where its value will be printed 42 jiffies later.
         fn print_later(value: Arc<MyStruct>) {
             let _ = workqueue::system().enqueue_delayed(value, 42);
         }

   - New 'bits' module: add support for 'bit' and 'genmask' functions,
     with runtime- and compile-time variants, e.g.:

         static_assert!(0b00010000 == bit_u8(4));
         static_assert!(0b00011110 == genmask_u8(1..=4));

         assert!(checked_bit_u32(u32::BITS).is_none());

   - 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which
     reads NUL-terminated strings from userspace into a '&CStr'

     Introduce 'UserPtr' newtype, similar in purpose to '__user' in C,
     to minimize mistakes handling userspace pointers, including mixing
     them up with integers and leaking them via the 'Debug' trait. Add
     it to the prelude, too

   - Start preparations for the replacement of our custom 'CStr' type
     with the analogous type in the 'core' standard library. This will
     take place across several cycles to make it easier. For this one,
     it includes a new 'fmt' module, using upstream method names and
     some other cleanups

     Replace 'fmt!' with a re-export, which helps Clippy lint properly,
     and clean up the found 'uninlined-format-args' instances

   - 'dma' module:

      - Clarify wording and be consistent in 'coherent' nomenclature

      - Convert the 'read!()' and 'write!()' macros to return a 'Result'

      - Add 'as_slice()', 'write()' methods in 'CoherentAllocation'

      - Expose 'count()' and 'size()' in 'CoherentAllocation' and add
        the corresponding type invariants

      - Implement 'CoherentAllocation::dma_handle_with_offset()'

   - 'time' module:

      - Make 'Instant' generic over clock source. This allows the
        compiler to assert that arithmetic expressions involving the
        'Instant' use 'Instants' based on the same clock source

      - Make 'HrTimer' generic over the timer mode. 'HrTimer' timers
        take a 'Duration' or an 'Instant' when setting the expiry time,
        depending on the timer mode. With this change, the compiler can
        check the type matches the timer mode

      - Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep
        function that will select an appropriate sleep method depending
        on the requested sleep time

      - Avoid 64-bit divisions on 32-bit hardware when calculating
        timestamps

      - Seal the 'HrTimerMode' trait. This prevents users of the
        'HrTimerMode' from implementing the trait on their own types

      - Pass the correct timer mode ID to 'hrtimer_start_range_ns()'

   - 'list' module: remove 'OFFSET' constants, allowing to remove
     pointer arithmetic; now 'impl_list_item!' invokes
     'impl_has_list_links!' or 'impl_has_list_links_self_ptr!'. Other
     simplifications too

   - 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a
     constant, which avoids exposing the type of the opaque pointer, and
     require 'into_foreign' to return non-null

     Remove the 'Either<L, R>' type as well. It is unused, and we want
     to encourage the use of custom enums for concrete use cases

   - 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types
     to allow them to be used in generic APIs

   - 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box<T, A>';
     and 'Borrow', 'BorrowMut' and 'Default' for 'Vec<T, A>'

   - 'Opaque' type: add 'cast_from' method to perform a restricted cast
     that cannot change the inner type and use it in callers of
     'container_of!'. Rename 'raw_get' to 'cast_into' to match it

   - 'rbtree' module: add 'is_empty' method

   - 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and
     'ARef', which are moved from the too general 'types' module which
     we want to reduce or eventually remove. Also fix a safety comment
     in 'static_lock_class'

  'pin-init' crate:

   - Add 'impl<T, E> [Pin]Init<T, E> for Result<T, E>', so results are
     now (pin-)initializers

   - Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()'

   - New 'zeroed()', a safe version of 'mem::zeroed()' and also provide
     it via 'Zeroable::zeroed()'

   - Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for
     'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for
     '"Rust"' and '"C"' ABIs and up to 20 arguments

   - Changed blanket impls of 'Init' and 'PinInit' from 'impl<T, E>
     [Pin]Init<T, E> for T' to 'impl<T> [Pin]Init<T> for T'

   - Renamed 'zeroed()' to 'init_zeroed()'

   - Upstream dev news: improve CI more to deny warnings, use
     '--all-targets'. Check the synchronization status of the two
     '-next' branches in upstream and the kernel

  MAINTAINERS:

   - Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo
     Stoakes as reviewers (thanks everyone)

  And a few other cleanups and improvements"

* tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (76 commits)
  rust: Add warn_on macro
  arm64/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
  riscv/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
  x86/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
  rust: kernel: move ARef and AlwaysRefCounted to sync::aref
  rust: sync: fix safety comment for `static_lock_class`
  rust: types: remove `Either<L, R>`
  rust: kernel: use `core::ffi::CStr` method names
  rust: str: add `CStr` methods matching `core::ffi::CStr`
  rust: str: remove unnecessary qualification
  rust: use `kernel::{fmt,prelude::fmt!}`
  rust: kernel: add `fmt` module
  rust: kernel: remove `fmt!`, fix clippy::uninlined-format-args
  scripts: rust: emit path candidates in panic message
  scripts: rust: replace length checks with match
  rust: list: remove nonexistent generic parameter in link
  rust: bits: add support for bits/genmask macros
  rust: list: remove OFFSET constants
  rust: list: add `impl_list_item!` examples
  rust: list: use fully qualified path
  ...
2025-08-03 13:49:10 -07:00
Daniel Almeida
bc4f9045a5 rust: platform: add resource accessors
The previous patches have added the abstractions for Resources and the
ability to map them and therefore read and write the underlying memory .

The only thing missing to make this accessible for platform devices is
to provide accessors that return instances of IoRequest<'a>. These
ensure that the resource are valid only for the lifetime of the platform
device, and that the platform device is in the Bound state.

Therefore, add these accessors. Also make it possible to retrieve
resources from platform devices in Rust using either a name or an index.

Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://lore.kernel.org/r/20250717-topics-tyr-platform_iomem-v15-3-beca780b77e3@collabora.com
[ Remove #[expect(dead_code)] from IoRequest::new() and move SAFETY
  comments right on top of unsafe blocks to avoid clippy warnings for
  some (older) clippy versions. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-20 19:43:14 +02:00
Danilo Krummrich
256de48f2c rust: platform: implement the dma::Device trait
The platform bus is potentially capable of performing DMA, hence implement
the `dma:Device` trait for `platform::Device`.

Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250716150354.51081-5-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-19 19:37:17 +02:00
Alice Ryhl
2f5606afa4 device: rust: rename Device::as_ref() to Device::from_raw()
The prefix as_* should not be used for a constructor. Constructors
usually use the prefix from_* instead.

Some prior art in the stdlib: Box::from_raw, CString::from_raw,
Rc::from_raw, Arc::from_raw, Waker::from_raw, File::from_raw_fd.

There is also prior art in the kernel crate: cpufreq::Policy::from_raw,
fs::File::from_raw_file, Kuid::from_raw, ARef::from_raw,
SeqFile::from_raw, VmaNew::from_raw, Io::from_raw.

Link: https://lore.kernel.org/r/aCd8D5IA0RXZvtcv@pollux
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250711-device-as-ref-v2-1-1b16ab6402d7@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-16 23:37:49 +02:00
Andreas Hindborg
12717ebeff rust: types: add FOREIGN_ALIGN to ForeignOwnable
The current implementation of `ForeignOwnable` is leaking the type of the
opaque pointer to consumers of the API. This allows consumers of the opaque
pointer to rely on the information that can be extracted from the pointer
type.

To prevent this, change the API to the version suggested by Maira
Canal (link below): Remove `ForeignOwnable::PointedTo` in favor of a
constant, which specifies the alignment of the pointers returned by
`into_foreign`.

With this change, `ArcInner` no longer needs `pub` visibility, so change it
to private.

Suggested-by: Alice Ryhl <aliceryhl@google.com>
Suggested-by: Maíra Canal <mcanal@igalia.com>
Link: https://lore.kernel.org/r/20240309235927.168915-3-mcanal@igalia.com
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250612-pointed-to-v3-1-b009006d86a1@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-07-14 23:55:24 +02:00
Danilo Krummrich
4be5f3fff1 rust: platform: implement Driver::unbind()
Currently, there's really only one core callback for drivers, which is
probe().

Now, this isn't entirely true, since there is also the drop() callback of
the driver type (serving as the driver's private data), which is returned
by probe() and is dropped in remove().

On the C side remove() mainly serves two purposes:

  (1) Tear down the device that is operated by the driver, e.g. call bus
      specific functions, write I/O memory to reset the device, etc.

  (2) Free the resources that have been allocated by a driver for a
      specific device.

The drop() callback mentioned above is intended to cover (2) as the Rust
idiomatic way.

However, it is partially insufficient and inefficient to cover (1)
properly, since drop() can't be called with additional arguments, such as
the reference to the corresponding device that has the correct device
context, i.e. the Core device context.

This makes it inefficient (but not impossible) to access device
resources, e.g. to write device registers, and impossible to call device
methods, which are only accessible under the Core device context.

In order to solve this, add an additional callback for (1), which we
call unbind().

The reason for calling it unbind() is that, unlike remove(), it is *only*
meant to be used to perform teardown operations on the device (1), but
*not* to release resources (2).

Link: https://lore.kernel.org/r/20250621195118.124245-7-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-09 00:04:33 +02:00
Danilo Krummrich
f0a68a912c rust: platform: use generic device drvdata accessors
Take advantage of the generic drvdata accessors of the generic Device
type.

While at it, use from_result() instead of match.

Link: https://lore.kernel.org/r/20250621195118.124245-4-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-09 00:04:33 +02:00
Tamir Duberstein
8ae33576ea rust: platform: remove unnecessary import
`kernel::str::CStr` is included in the prelude.

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250704-cstr-include-platform-v1-1-ff7803ee7a81@gmail.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-07-05 17:07:24 +02:00
Igor Korotin
8411e6f06a rust: platform: Add ACPI match table support to Driver trait
Extend the `platform::Driver` trait to support ACPI device matching by
adding the `ACPI_ID_TABLE` constant.

This allows Rust platform drivers to define ACPI match tables alongside
their existing OF match tables. These changes mirror the existing OF
support and allow Rust platform drivers to match devices based on ACPI
identifiers.

Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com>
Link: https://lore.kernel.org/r/20250620154334.298320-1-igor.korotin.linux@gmail.com
[ Use 'LNUXBEEF' as ACPI ID. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-26 23:26:15 +02:00
Igor Korotin
ec3ef2175e rust: platform: Set OF_ID_TABLE default to None in Driver trait
Provide a default value of `None` for `Driver::OF_ID_TABLE` to simplify
driver implementations.

Drivers that do not require OpenFirmware matching no longer need to
import the `of` module or define the constant explicitly.

This reduces unnecessary boilerplate and avoids pulling in unused
dependencies.

Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com>
Link: https://lore.kernel.org/r/20250620154124.297158-1-igor.korotin.linux@gmail.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-26 23:26:15 +02:00
Igor Korotin
7a5cb145a9 rust: driver: Add ACPI id table support to Adapter trait
Extend the `Adapter` trait to support ACPI device identification.

This mirrors the existing Open Firmware (OF) support (`of_id_table`) and
enables Rust drivers to match and retrieve ACPI-specific device data
when `CONFIG_ACPI` is enabled.

To avoid breaking compilation, a stub implementation of `acpi_id_table()`
is added to the Platform adapter; the full implementation will be provided
in a subsequent patch.

Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com>
Link: https://lore.kernel.org/r/20250620153914.295679-1-igor.korotin.linux@gmail.com
[ Fix clippy warning if #[cfg(not(CONFIG_OF))]; fix checkpatch.pl line
  length warnings. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-26 23:26:10 +02:00
Viresh Kumar
b6985083be rust: Use consistent "# Examples" heading style in rustdoc
Use a consistent `# Examples` heading in rustdoc across the codebase.

Some modules previously used `## Examples` (even when they should be
available as top-level headers), while others used `# Example`, which
deviates from the preferred `# Examples` style.

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/ddd5ce0ac20c99a72a4f1e4322d3de3911056922.1749545815.git.viresh.kumar@linaro.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-06-24 01:02:30 +02:00
Tamir Duberstein
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
Linus Torvalds
ec7714e494 Rust changes for v6.16
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.
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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
Miguel Ojeda
9f04763683 rust: platform: fix docs related to missing Markdown code spans
Convert `TODO` from documentation to a normal comment, and put code in
block.

This was found using the Clippy `doc_markdown` lint, which we may want
to enable.

Fixes: 683a63befc ("rust: platform: add basic platform device / driver abstractions")
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250324210359.1199574-9-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-25 22:58:35 +02:00
Tamir Duberstein
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
Danilo Krummrich
a38dfd60fe rust: platform: impl TryFrom<&Device> for &platform::Device
Implement TryFrom<&device::Device> for &Device.

This allows us to get a &platform::Device from a generic &Device in a safe
way; the conversion fails if the device' bus type does not match with
the platform bus type.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250321214826.140946-4-dakr@kernel.org
[ Support device context types, use dev_is_platform() helper. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-19 10:20:25 +02:00
Danilo Krummrich
da6c47c6cb rust: platform: preserve device context in AsRef
Since device::Device has a generic over its context, preserve this
device context in AsRef.

For instance, when calling platform::Device<Core> the new AsRef
implementation returns device::Device<Core>.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-5-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:45 +02:00
Danilo Krummrich
fbb92b6a53 rust: device: implement impl_device_context_into_aref!
Implement a macro to implement all From conversions of a certain device
to ARef<Device>.

This avoids unnecessary boiler plate code for every device
implementation.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-3-dakr@kernel.org
[ Add missing `::` prefix in macros. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:27 +02:00
Danilo Krummrich
cb271c2edf rust: device: implement impl_device_context_deref!
The Deref hierarchy for device context generics is the same for every
(bus specific) device.

Implement those with a generic macro to avoid duplicated boiler plate
code and ensure the correct Deref hierarchy for every device
implementation.

Co-developed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Link: https://lore.kernel.org/r/20250413173758.12068-2-dakr@kernel.org
[ Add missing `::` prefix in macros. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:11 +02:00
Linus Torvalds
2cd5769fb0 Driver core updates for 6.15-rc1
Here is the big set of driver core updates for 6.15-rc1.  Lots of stuff
 happened this development cycle, including:
   - kernfs scaling changes to make it even faster thanks to rcu
   - bin_attribute constify work in many subsystems
   - faux bus minor tweaks for the rust bindings
   - rust binding updates for driver core, pci, and platform busses,
     making more functionaliy available to rust drivers.  These are all
     due to people actually trying to use the bindings that were in 6.14.
   - make Rafael and Danilo full co-maintainers of the driver core
     codebase
   - other minor fixes and updates.
 
 This has been in linux-next for a while now, with the only reported
 issue being some merge conflicts with the rust tree.  Depending on which
 tree you pull first, you will have conflicts in one of them.  The merge
 resolution has been in linux-next as an example of what to do, or can be
 found here:
 	https://lore.kernel.org/r/CANiq72n3Xe8JcnEjirDhCwQgvWoE65dddWecXnfdnbrmuah-RQ@mail.gmail.com
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updatesk from Greg KH:
 "Here is the big set of driver core updates for 6.15-rc1. Lots of stuff
  happened this development cycle, including:

   - kernfs scaling changes to make it even faster thanks to rcu

   - bin_attribute constify work in many subsystems

   - faux bus minor tweaks for the rust bindings

   - rust binding updates for driver core, pci, and platform busses,
     making more functionaliy available to rust drivers. These are all
     due to people actually trying to use the bindings that were in
     6.14.

   - make Rafael and Danilo full co-maintainers of the driver core
     codebase

   - other minor fixes and updates"

* tag 'driver-core-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (52 commits)
  rust: platform: require Send for Driver trait implementers
  rust: pci: require Send for Driver trait implementers
  rust: platform: impl Send + Sync for platform::Device
  rust: pci: impl Send + Sync for pci::Device
  rust: platform: fix unrestricted &mut platform::Device
  rust: pci: fix unrestricted &mut pci::Device
  rust: device: implement device context marker
  rust: pci: use to_result() in enable_device_mem()
  MAINTAINERS: driver core: mark Rafael and Danilo as co-maintainers
  rust/kernel/faux: mark Registration methods inline
  driver core: faux: only create the device if probe() succeeds
  rust/faux: Add missing parent argument to Registration::new()
  rust/faux: Drop #[repr(transparent)] from faux::Registration
  rust: io: fix devres test with new io accessor functions
  rust: io: rename `io::Io` accessors
  kernfs: Move dput() outside of the RCU section.
  efi: rci2: mark bin_attribute as __ro_after_init
  rapidio: constify 'struct bin_attribute'
  firmware: qemu_fw_cfg: constify 'struct bin_attribute'
  powerpc/perf/hv-24x7: Constify 'struct bin_attribute'
  ...
2025-04-01 11:02:03 -07:00
Danilo Krummrich
51d0de7596 rust: platform: require Send for Driver trait implementers
The instance of Self, returned and created by Driver::probe() is
dropped in the bus' remove() callback.

Request implementers of the Driver trait to implement Send, since the
remove() callback is not guaranteed to run from the same thread as
probe().

Fixes: 683a63befc ("rust: platform: add basic platform device / driver abstractions")
Cc: stable <stable@kernel.org>
Reported-by: Alice Ryhl <aliceryhl@google.com>
Closes: https://lore.kernel.org/lkml/Z9rDxOJ2V2bPjj5i@google.com/
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250319145350.69543-2-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20 07:41:11 -07:00
Danilo Krummrich
455943aa18 rust: platform: impl Send + Sync for platform::Device
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>
2025-03-18 16:55:12 -07:00
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
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
Danilo Krummrich
e1a51c2bf4 rust: driver: address soundness issue in RegistrationOps
The `RegistrationOps` trait holds some obligations to the caller and
implementers. While being documented, the trait and the corresponding
functions haven't been marked as unsafe.

Hence, markt the trait and functions unsafe and add the corresponding
safety comments.

This patch does not include any fuctional changes.

Reported-by: Gary Guo <gary@garyguo.net>
Closes: https://lore.kernel.org/rust-for-linux/20241224195821.3b43302b.gary@garyguo.net/
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20250103164655.96590-4-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-07 11:31:45 +01:00
Danilo Krummrich
683a63befc rust: platform: add basic platform device / driver abstractions
Implement the basic platform bus abstractions required to write a basic
platform driver. This includes the following data structures:

The `platform::Driver` trait represents the interface to the driver and
provides `platform::Driver::probe` for the driver to implement.

The `platform::Device` abstraction represents a `struct platform_device`.

In order to provide the platform bus specific parts to a generic
`driver::Registration` the `driver::RegistrationOps` trait is implemented
by `platform::Adapter`.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-15-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20 17:21:05 +01:00