linux/rust/kernel/miscdevice.rs, branch v6.16

Merge tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2025-06-06T18:50:47Z

Pull char / misc / iio driver updates from Greg KH: "Here is the big char/misc/iio and other small driver subsystem pull request for 6.16-rc1. Overall, a lot of individual changes, but nothing major, just the normal constant forward progress of new device support and cleanups to existing subsystems. Highlights in here are: - Large IIO driver updates and additions and device tree changes - Android binder bugfixes and logfile fixes - mhi driver updates - comedi driver updates - counter driver updates and additions - coresight driver updates and additions - echo driver removal as there are no in-kernel users of it - nvmem driver updates - spmi driver updates - new amd-sbi driver "subsystem" and drivers added - rust miscdriver binding documentation fix - other small driver fixes and updates (uio, w1, acrn, hpet, xillybus, cardreader drivers, fastrpc and others) All of these have been in linux-next for quite a while with no reported problems" * tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (390 commits) binder: fix yet another UAF in binder_devices counter: microchip-tcb-capture: Add watch validation support dt-bindings: iio: adc: Add ROHM BD79100G iio: adc: add support for Nuvoton NCT7201 dt-bindings: iio: adc: add NCT7201 ADCs iio: chemical: Add driver for SEN0322 dt-bindings: trivial-devices: Document SEN0322 iio: adc: ad7768-1: reorganize driver headers iio: bmp280: zero-init buffer iio: ssp_sensors: optimalize -> optimize HID: sensor-hub: Fix typo and improve documentation iio: admv1013: replace redundant ternary operator with just len iio: chemical: mhz19b: Fix error code in probe() iio: adc: at91-sama5d2: use IIO_DECLARE_BUFFER_WITH_TS iio: accel: sca3300: use IIO_DECLARE_BUFFER_WITH_TS iio: adc: ad7380: use IIO_DECLARE_DMA_BUFFER_WITH_TS iio: adc: ad4695: rename AD4695_MAX_VIN_CHANNELS iio: adc: ad4695: use IIO_DECLARE_DMA_BUFFER_WITH_TS iio: introduce IIO_DECLARE_BUFFER_WITH_TS macros iio: make IIO_DMA_MINALIGN minimum of 8 bytes ...

Merge tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

2025-06-05T04:18:37Z

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' to 'Box' 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 ('$field_ptr'). - Support optional message in 'static_assert!'. - Add C FFI types (e.g. 'c_int') to the prelude. - 'str' module: simplify KUnit tests 'format!' macro, convert 'rusttest' tests into KUnit, take advantage of the '-> Result' support in KUnit '#[test]'s. - 'list' module: add examples for 'List', fix path of 'assert_pinned!' (so far unused macro rule). - 'workqueue' module: remove 'HasWork::OFFSET'. - 'page' module: add 'inline' attribute. 'macros' crate: - 'module' macro: place 'cleanup_module()' in '.exit.text' section. 'pin-init' crate: - Add 'Wrapper' trait for creating pin-initializers for wrapper structs with a structurally pinned value such as 'UnsafeCell' or 'MaybeUninit'. - Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but not error if not all fields implement it. This is needed to derive 'Zeroable' for all bindgen-generated structs. - Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the initialized type of an initializer. These are utilized by the 'Wrapper' implementations. - Add support for visibility in 'Zeroable' derive macro. - Add support for 'union's in 'Zeroable' derive macro. - Upstream dev news: streamline CI, fix some bugs. Add new workflows to check if the user-space version and the one in the kernel tree have diverged. Use the issues tab [1] to track them, which should help folks report and diagnose issues w.r.t. 'pin-init' better. [1] https://github.com/rust-for-linux/pin-init/issues Documentation: - Testing: add docs on the new KUnit '#[test]' tests. - Coding guidelines: explain that '///' vs. '//' applies to private items too. Add section on C FFI types. - Quick Start guide: update Ubuntu instructions and split them into "25.04" and "24.04 LTS and older". And a few other cleanups and improvements" * tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (78 commits) rust: list: Fix typo `much` in arc.rs rust: check type of `$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 ...

rust: miscdevice: fix typo in MiscDevice::ioctl documentation

2025-05-21T12:03:20Z

Fixes one small typo (`utilties` to `utilities`) in the documentation of `MiscDevice::ioctl`. Fixes: f893691e7426 ("rust: miscdevice: add base miscdevice abstraction") Signed-off-by: Christian Schrefl Reviewed-by: Benno Lossin Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250517-rust_miscdevice_fix_typo-v1-1-8c30a6237ba9@gmail.com Signed-off-by: Greg Kroah-Hartman

rust: miscdevice: add mmap support

2025-05-12T00:48:25Z

Add the ability to write a file_operations->mmap hook in Rust when using the miscdevice abstraction. The `vma` argument to the `mmap` hook uses the `VmaNew` type from the previous commit; this type provides the correct set of operations for a file_operations->mmap hook. Link: https://lkml.kernel.org/r/20250408-vma-v16-7-d8b446e885d9@google.com Signed-off-by: Alice Ryhl Acked-by: Greg Kroah-Hartman Acked-by: Lorenzo Stoakes Acked-by: Liam R. Howlett Reviewed-by: Andreas Hindborg Reviewed-by: Gary Guo Cc: Alex Gaynor Cc: Arnd Bergmann Cc: Balbir Singh Cc: Benno Lossin Cc: Björn Roy Baron Cc: Boqun Feng Cc: Jann Horn Cc: John Hubbard Cc: Matthew Wilcox (Oracle) Cc: Miguel Ojeda Cc: Suren Baghdasaryan Cc: Trevor Gross Cc: Vlastimil Babka Signed-off-by: Andrew Morton

rust: types: add `ForeignOwnable::PointedTo`

2025-05-01T09:35:49Z

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 Signed-off-by: Tamir Duberstein Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250423-rust-xarray-bindings-v19-1-83cdcf11c114@gmail.com Signed-off-by: Andreas Hindborg

rust: miscdevice: change how f_ops vtable is constructed

2025-03-07T17:20:36Z

I was helping someone with writing a new Rust abstraction, and we were using the miscdevice abstraction as an example. While doing this, it became clear to me that the way I implemented the f_ops vtable is confusing to new Rust users, and that the approach used by the block abstractions is less confusing. Thus, update the miscdevice abstractions to use the same approach as rust/kernel/block/mq/operations.rs. Sorry about the large diff. This changes the indentation of a large amount of code. Reviewed-by: Christian Schrefl Signed-off-by: Alice Ryhl Link: https://lore.kernel.org/r/20250227-miscdevice-fops-change-v1-1-c9e9b75d67eb@google.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2025-01-28T20:25:12Z

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 ...

rust: kernel: change `ForeignOwnable` pointer to mut

2025-01-13T22:45:31Z

It is slightly more convenient to operate on mut pointers, and this also properly conveys the desired ownership semantics of the trait. Reviewed-by: Alice Ryhl Reviewed-by: Andreas Hindborg Signed-off-by: Tamir Duberstein Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241120-borrow-mut-v6-4-80dbadd00951@gmail.com [ Reworded title slightly. - Miguel ] Signed-off-by: Miguel Ojeda

miscdevice: rust: use build_error! macro instead of function

2025-01-10T12:23:57Z

The function called build_error is an implementation detail of the macro of the same name. Thus, update miscdevice to use the macro rather than the function. See [1] for more information on this. These use the macro with the kernel:: prefix as it has not yet been added to the prelude. Reported-by: Stephen Rothwell Link: https://lore.kernel.org/r/20250110162828.38614c1b@canb.auug.org.au Link: https://lore.kernel.org/all/20241123222849.350287-2-ojeda@kernel.org/ [1] Signed-off-by: Alice Ryhl Acked-by: Miguel Ojeda Link: https://lore.kernel.org/r/20250110101459.536726-1-aliceryhl@google.com Signed-off-by: Greg Kroah-Hartman

rust: add `build_error!` to the prelude

2025-01-09T23:19:09Z

The sibling `build_assert!` is already in the prelude, it makes sense that a "core"/"language" facility like this is part of the prelude and users should not be defining their own one (thus there should be no risk of future name collisions and we would want to be aware of them anyway). Thus add `build_error!` into the prelude. Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20241123222849.350287-3-ojeda@kernel.org [ Applied the change to the new miscdevice cases. - Miguel ] Signed-off-by: Miguel Ojeda