Commit Graph

16 Commits

Author SHA1 Message Date
Linus Torvalds
22c5696e3f Merge tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Remove unneeded debugfs_file_{get,put}() instances
   - Remove last remnants of debugfs_real_fops()
   - Allow storing non-const void * in struct debugfs_inode_info::aux

  sysfs:
   - Switch back to attribute_group::bin_attrs (treewide)
   - Switch back to bin_attribute::read()/write() (treewide)
   - Constify internal references to 'struct bin_attribute'

  Support cache-ids for device-tree systems:
   - Add arch hook arch_compact_of_hwid()
   - Use arch_compact_of_hwid() to compact MPIDR values on arm64

  Rust:
   - Device:
       - Introduce CoreInternal device context (for bus internal methods)
       - Provide generic drvdata accessors for bus devices
       - Provide Driver::unbind() callbacks
       - Use the infrastructure above for auxiliary, PCI and platform
       - Implement Device::as_bound()
       - Rename Device::as_ref() to Device::from_raw() (treewide)
       - Implement fwnode and device property abstractions
       - Implement example usage in the Rust platform sample driver
   - Devres:
       - Remove the inner reference count (Arc) and use pin-init instead
       - Replace Devres::new_foreign_owned() with devres::register()
       - Require T to be Send in Devres<T>
       - Initialize the data kept inside a Devres last
       - Provide an accessor for the Devres associated Device
   - Device ID:
       - Add support for ACPI device IDs and driver match tables
       - Split up generic device ID infrastructure
       - Use generic device ID infrastructure in net::phy
   - DMA:
       - Implement the dma::Device trait
       - Add DMA mask accessors to dma::Device
       - Implement dma::Device for PCI and platform devices
       - Use DMA masks from the DMA sample module
   - I/O:
       - Implement abstraction for resource regions (struct resource)
       - Implement resource-based ioremap() abstractions
       - Provide platform device accessors for I/O (remap) requests
   - Misc:
       - Support fallible PinInit types in Revocable
       - Implement Wrapper<T> for Opaque<T>
       - Merge pin-init blanket dependencies (for Devres)

  Misc:
   - Fix OF node leak in auxiliary_device_create()
   - Use util macros in device property iterators
   - Improve kobject sample code
   - Add device_link_test() for testing device link flags
   - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
   - Hint to prefer container_of_const() over container_of()"

* tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (84 commits)
  rust: io: fix broken intra-doc links to `platform::Device`
  rust: io: fix broken intra-doc link to missing `flags` module
  rust: io: mem: enable IoRequest doc-tests
  rust: platform: add resource accessors
  rust: io: mem: add a generic iomem abstraction
  rust: io: add resource abstraction
  rust: samples: dma: set DMA mask
  rust: platform: implement the `dma::Device` trait
  rust: pci: implement the `dma::Device` trait
  rust: dma: add DMA addressing capabilities
  rust: dma: implement `dma::Device` trait
  rust: net::phy Change module_phy_driver macro to use module_device_table macro
  rust: net::phy represent DeviceId as transparent wrapper over mdio_device_id
  rust: device_id: split out index support into a separate trait
  device: rust: rename Device::as_ref() to Device::from_raw()
  arm64: cacheinfo: Provide helper to compress MPIDR value into u32
  cacheinfo: Add arch hook to compress CPU h/w id into 32 bits for cache-id
  cacheinfo: Set cache 'id' based on DT data
  container_of: Document container_of() is not to be used in new code
  driver core: auxiliary bus: fix OF node leak
  ...
2025-07-29 12:15:39 -07:00
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
Tamir Duberstein
3d44147494 rust: drm: remove unnecessary imports
`kernel::str::CStr` is included in the prelude.

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250704-cstr-include-drm-v1-1-a279dfc4d753@gmail.com
2025-07-05 13:01:59 +02:00
Danilo Krummrich
2e9fdbe5ec rust: drm: device: drop_in_place() the drm::Device in release()
In drm::Device::new() we allocate with __drm_dev_alloc() and return an
ARef<drm::Device>.

When the reference count of the drm::Device falls to zero, the C code
automatically calls drm_dev_release(), which eventually frees the memory
allocated in drm::Device::new().

However, due to that, drm::Device::drop() is never called. As a result
the destructor of the user's private data, i.e. drm::Device::data is
never called. Hence, fix this by calling drop_in_place() from the DRM
device's release callback.

Fixes: 1e4b8896c0 ("rust: drm: add device abstraction")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250629153747.72536-1-dakr@kernel.org
2025-07-04 00:33:56 +02:00
Danilo Krummrich
46ae8fd738 rust: devres: replace Devres::new_foreign_owned()
Replace Devres::new_foreign_owned() with devres::register().

The current implementation of Devres::new_foreign_owned() creates a full
Devres container instance, including the internal Revocable and
completion.

However, none of that is necessary for the intended use of giving full
ownership of an object to devres and getting it dropped once the given
device is unbound.

Hence, implement devres::register(), which is limited to consume the
given data, wrap it in a KBox and drop the KBox once the given device is
unbound, without any other synchronization.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Simona Vetter <simona.vetter@ffwll.ch>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250626200054.243480-3-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-28 18:06:53 +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
Lyude Paul
38cb08c3fc rust: drm: gem: Implement AlwaysRefCounted for all gem objects automatically
Currently we are requiring AlwaysRefCounted in most trait bounds for gem
objects, and implementing it by hand for our only current type of gem
object. However, all gem objects use the same functions for reference
counting - and all gem objects support reference counting.

We're planning on adding support for shmem gem objects, let's move this
around a bit by instead making IntoGEMObject require AlwaysRefCounted as a
trait bound, and then provide a blanket AlwaysRefCounted implementation for
any object that implements IntoGEMObject so all gem object types can use
the same AlwaysRefCounted implementation. This also makes things less
verbose by making the AlwaysRefCounted trait bound implicit for any
IntoGEMObject bound.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://lore.kernel.org/r/20250513221046.903358-5-lyude@redhat.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-05-14 00:37:16 +02:00
Lyude Paul
b36ff40b4a rust: drm: gem: s/into_gem_obj()/as_raw()/
There's a few changes here:
* The rename, of course (this should also let us drop the clippy annotation
  here)
* Return *mut bindings::drm_gem_object instead of
  &Opaque<bindings::drm_gem_object> - the latter doesn't really have any
  benefit and just results in conversion from the rust type to the C type
  having to be more verbose than necessary.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://lore.kernel.org/r/20250513221046.903358-4-lyude@redhat.com
[ Fixup s/into_gem_obj()/as_raw()/ in safety comment. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-05-14 00:35:58 +02:00
Lyude Paul
36b1ccbfa0 rust: drm: gem: Refactor IntoGEMObject::from_gem_obj() to as_ref()
There's a few issues with this function, mainly:

* This function -probably- should have been unsafe from the start. Pointers
  are not always necessarily valid, but you want a function that does
  field-projection for a pointer that can travel outside of the original
  struct to be unsafe, at least if I understand properly.
* *mut Self is not terribly useful in this context, the majority of uses of
  from_gem_obj() grab a *mut Self and then immediately convert it into a
  &'a Self. It also goes against the ffi conventions we've set in the rest
  of the kernel thus far.
* from_gem_obj() also doesn't follow the naming conventions in the rest of
  the DRM bindings at the moment, as_ref() would be a better name.

So, let's:

* Make from_gem_obj() unsafe
* Convert it to return &'a Self
* Rename it to as_ref()
* Update all call locations

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://lore.kernel.org/r/20250513221046.903358-3-lyude@redhat.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-05-14 00:26:16 +02:00
Lyude Paul
6ee48aee8c rust: drm: gem: Use NonNull for Object::dev
There is usually not much of a reason to use a raw pointer in a data
struct, so move this to NonNull instead.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://lore.kernel.org/r/20250513221046.903358-2-lyude@redhat.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-05-14 00:26:08 +02:00
Asahi Lina
c284d3e423 rust: drm: gem: Add GEM object abstraction
DRM GEM is the DRM memory management subsystem used by most modern
drivers; add a Rust abstraction for DRM GEM.

This includes the BaseObject trait, which contains operations shared by
all GEM object classes.

Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-8-dakr@kernel.org
[ Rework of GEM object abstractions
    * switch to the Opaque<T> type
    * fix (mutable) references to struct drm_gem_object (which in this
      context is UB)
    * drop all custom reference types in favor of AlwaysRefCounted
    * bunch of minor changes and simplifications (e.g. IntoGEMObject
      trait)
    * write and fix safety and invariant comments
    * remove necessity for and convert 'as' casts
    * original source archive: https://archive.is/dD5SL

  - Danilo ]
[ Fix missing CONFIG_DRM guards in rust/helpers/drm.c. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-28 10:08:23 +02:00
Asahi Lina
a98a73be9e rust: drm: file: Add File abstraction
A DRM File is the DRM counterpart to a kernel file structure,
representing an open DRM file descriptor.

Add a Rust abstraction to allow drivers to implement their own File types
that implement the DriverFile trait.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-7-dakr@kernel.org
[ Rework of drm::File
    * switch to the Opaque<T> type
    * fix (mutable) references to struct drm_file (which in this context
      is UB)
    * restructure and rename functions to align with common kernel
      schemes
    * write and fix safety and invariant comments
    * remove necessity for and convert 'as' casts
    * original source archive: https://archive.is/GH8oy

  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-24 14:11:58 +02:00
Asahi Lina
0600032c54 rust: drm: add DRM driver registration
Implement the DRM driver `Registration`.

The `Registration` structure is responsible to register and unregister a
DRM driver. It makes use of the `Devres` container in order to allow the
`Registration` to be owned by devres, such that it is automatically
dropped (and the DRM driver unregistered) once the parent device is
unbound.

Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-6-dakr@kernel.org
[ Rework of drm::Registration
    * move VTABLE to drm::Device to prevent use-after-free bugs; VTABLE
      needs to be bound to the lifetime of drm::Device, not the
      drm::Registration
    * combine new() and register() to get rid of the registered boolean
    * remove file_operations
    * move struct drm_device creation to drm::Device
    * introduce Devres
    * original source archive: https://archive.is/Pl9ys

  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-24 14:00:13 +02:00
Asahi Lina
1e4b8896c0 rust: drm: add device abstraction
Implement the abstraction for a `struct drm_device`.

A `drm::Device` creates a static const `struct drm_driver` filled with
the data from the `drm::Driver` trait implementation of the actual
driver creating the `drm::Device`.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-5-dakr@kernel.org
[ Rewrite of drm::Device
    * full rewrite of the drm::Device abstraction using the subclassing
      pattern
    * original source archive: http://archive.today/5NxBo

  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-24 14:00:10 +02:00
Asahi Lina
07c9016085 rust: drm: add driver abstractions
Implement the DRM driver abstractions.

The `Driver` trait provides the interface to the actual driver to fill
in the driver specific data, such as the `DriverInfo`, driver features
and IOCTLs.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-4-dakr@kernel.org
[ MISC changes
    * remove unnecessary DRM features; make remaining ones crate private
    * add #[expect(unused)] to avoid warnings
    * add sealed trait
    * remove shmem::Object references
    * original source archive: https://archive.is/Pl9ys

  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-24 13:50:10 +02:00
Asahi Lina
9a69570682 rust: drm: ioctl: Add DRM ioctl abstraction
DRM drivers need to be able to declare which driver-specific ioctls they
support. Add an abstraction implementing the required types and a helper
macro to generate the ioctl definition inside the DRM driver.

Note that this macro is not usable until further bits of the abstraction
are in place (but it will not fail to compile on its own, if not called).

Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-3-dakr@kernel.org
[ MISC fixes
    * wrap raw_data in Opaque to avoid UB when creating a reference
    * fix IOCTL sample declaration
    * fix safety comment of IOCTL argument
    * original source archive: https://archive.is/LqHDQ

  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-24 13:50:05 +02:00