Commit Graph

1278 Commits

Author SHA1 Message Date
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
Miguel Ojeda
fc55584e00 rust: device: conditionally expect dead_code for parent()
When `CONFIG_AUXILIARY_BUS` is disabled, `parent()` is still dead code:

    error: method `parent` is never used
      --> rust/kernel/device.rs:71:19
       |
    64 | impl<Ctx: DeviceContext> Device<Ctx> {
       | ------------------------------------ method in this implementation
    ...
    71 |     pub(crate) fn parent(&self) -> Option<&Self> {
       |                   ^^^^^^
       |
       = note: `-D dead-code` implied by `-D warnings`
       = help: to override `-D warnings` add `#[allow(dead_code)]`

Thus reintroduce the `expect`, but now as a conditional one. Do so as
`dead_code` since that is narrower.

An `allow` would also be possible, but Danilo wants to catch new users
in the future [1].

Link: https://lore.kernel.org/rust-for-linux/aBE8qQrpXOfru_K3@pollux/ [1]
Fixes: ce735e73dd ("rust: auxiliary: add auxiliary device / driver abstractions")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250429210629.513521-1-ojeda@kernel.org
[ Adjust commit subject to "rust: device: conditionally expect
  `dead_code` for `parent()`". - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-29 23:45:54 +02:00
FUJITA Tomonori
ddc6715064 rust: time: Introduce Instant type
Introduce a type representing a specific point in time. We could use
the Ktime type but C's ktime_t is used for both timestamp and
timedelta. To avoid confusion, introduce a new Instant type for
timestamp.

Rename Ktime to Instant and modify their methods for timestamp.

Implement the subtraction operator for Instant:

Delta = Instant A - Instant B

Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Link: https://lore.kernel.org/r/20250423192857.199712-5-fujita.tomonori@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-04-29 15:31:07 +02:00
FUJITA Tomonori
fae0cdc123 rust: time: Introduce Delta type
Introduce a type representing a span of time. Define our own type
because `core::time::Duration` is large and could panic during
creation.

time::Ktime could be also used for time duration but timestamp and
timedelta are different so better to use a new type.

i64 is used instead of u64 to represent a span of time; some C drivers
uses negative Deltas and i64 is more compatible with Ktime using i64
too (e.g., ktime_[us|ms]_delta() APIs return i64 so we create Delta
object without type conversion.

i64 is used instead of bindings::ktime_t because when the ktime_t
type is used as timestamp, it represents values from 0 to
KTIME_MAX, which is different from Delta.

as_millis() method isn't used in this patchset. It's planned to be
used in Binder driver.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Link: https://lore.kernel.org/r/20250423192857.199712-4-fujita.tomonori@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-04-29 15:31:07 +02:00
FUJITA Tomonori
3caad57d29 rust: time: Add PartialEq/Eq/PartialOrd/Ord trait to Ktime
Add PartialEq/Eq/PartialOrd/Ord trait to Ktime so two Ktime instances
can be compared to determine whether a timeout is met or not.

Use the derive implements; we directly touch C's ktime_t rather than
using the C's accessors because it is more efficient and we already do
in the existing code (Ktime::sub).

Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Link: https://lore.kernel.org/r/20250423192857.199712-3-fujita.tomonori@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-04-29 15:31:07 +02:00
FUJITA Tomonori
1116f0c5ff rust: hrtimer: Add Ktime temporarily
Add Ktime temporarily until hrtimer is refactored to use Instant and
Delta types.

Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Link: https://lore.kernel.org/r/20250423192857.199712-2-fujita.tomonori@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-04-29 15:31:07 +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
Linus Torvalds
3ae7f5093e Merge tag 'driver-core-6.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core fixes from Greg KH:
 "Here are some small driver core fixes to resolve a number of reported
  problems. Included in here are:

   - driver core sync fix revert to resolve a much reported problem,
     hopefully this is finally resolved

   - MAINTAINERS file update, documenting that the driver-core tree is
     now under a "shared" maintainership model, thanks to Rafael and
     Danilo for offering to do this!

   - auxbus documentation and MAINTAINERS file update

   - MAINTAINERS file update for Rust PCI code

   - firmware rust binding fixup

   - software node link fix

  All of these have been in linux-next for over a week with no reported
  issues"

* tag 'driver-core-6.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
  drivers/base/memory: Avoid overhead from for_each_present_section_nr()
  software node: Prevent link creation failure from causing kobj reference count imbalance
  device property: Add a note to the fwnode.h
  drivers/base: Add myself as auxiliary bus reviewer
  drivers/base: Extend documentation with preferred way to use auxbus
  driver core: fix potential NULL pointer dereference in dev_uevent()
  driver core: introduce device_set_driver() helper
  Revert "drivers: core: synchronize really_probe() and dev_uevent()"
  MAINTAINERS: update the location of the driver-core git tree
  rust: firmware: Use `ffi::c_char` type in `FwFunc`
  MAINTAINERS: pci: add entry for Rust PCI code
2025-04-25 10:02:59 -07:00
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
Tamir Duberstein
88d5d6a38d rust: alloc: replace Vec::set_len with inc_len
Rename `set_len` to `inc_len` and simplify its safety contract.

Note that the usage in `CString::try_from_fmt` remains correct as the
receiver is known to have `len == 0`.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250416-vec-set-len-v4-4-112b222604cd@gmail.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-23 12:05:23 +02:00
Tamir Duberstein
1b04b466c8 rust: alloc: refactor Vec::truncate using dec_len
Use `checked_sub` to satisfy the safety requirements of `dec_len` and
replace nearly the whole body of `truncate` with a call to `dec_len`.

Reviewed-by: Andrew Ballance <andrewjballance@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250416-vec-set-len-v4-3-112b222604cd@gmail.com
[ Remove #[expect(unused)] from dec_len(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-23 12:05:22 +02:00
Tamir Duberstein
dbb0b840a0 rust: alloc: add Vec::dec_len
Add `Vec::dec_len` that reduces the length of the receiver. This method
is intended to be used from methods that remove elements from `Vec` such
as `truncate`, `pop`, `remove`, and others. This method is intentionally
not `pub`.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250416-vec-set-len-v4-2-112b222604cd@gmail.com
[ Add #[expect(unused)] to dec_len(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-23 12:05:22 +02:00
Tamir Duberstein
47a17a63f9 rust: alloc: add Vec::len() <= Vec::capacity invariant
Document the invariant that the vector's length is always less than or
equal to its capacity. This is already implied by these other
invariants:

- `self.len` always represents the exact number of elements stored in
  the vector.
- `self.layout` represents the absolute number of elements that can be
  stored within the vector without re-allocation.

but it doesn't hurt to spell it out. Note that the language references
`self.capacity` rather than `self.layout.len` as the latter is zero for
a vector of ZSTs.

Update a safety comment touched by this patch to correctly reference
`realloc` rather than `alloc` and replace "leaves" with "leave" to
improve grammar.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250416-vec-set-len-v4-1-112b222604cd@gmail.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-23 12:05:15 +02:00
Alexandre Courbot
85f8e98dbb rust: alloc: allow coercion from Box<T> to Box<dyn U> if T implements U
This enables the creation of trait objects backed by a Box, similarly to
what can be done with the standard library.

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://lore.kernel.org/r/20250412-box_trait_objs-v3-1-f67ced62d520@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-22 17:29:37 +02:00
Alexandre Courbot
80e62fcea4 rust/revocable: add try_access_with() convenience method
Revocable::try_access() returns a guard through which the wrapped object
can be accessed. Code that can sleep is not allowed while the guard is
held; thus, it is common for the caller to explicitly drop it before
running sleepable code, e.g:

    let b = bar.try_access()?;
    let reg = b.readl(...);

    // Don't forget this or things could go wrong!
    drop(b);

    something_that_might_sleep();

    let b = bar.try_access()?;
    let reg2 = b.readl(...);

This is arguably error-prone. try_access_with() provides an arguably
safer alternative, by taking a closure that is run while the guard is
held, and by dropping the guard automatically after the closure
completes. This way, code can be organized more clearly around the
critical sections and the risk of forgetting to release the guard when
needed is considerably reduced:

    let reg = bar.try_access_with(|b| b.readl(...))?;

    something_that_might_sleep();

    let reg2 = bar.try_access_with(|b| b.readl(...))?;

The closure can return nothing, or any value including a Result which is
then wrapped inside the Option returned by try_access_with. Error
management is driver-specific, so users are encouraged to create their
own macros that map and flatten the returned values to something
appropriate for the code they are working on.

Suggested-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250411-try_with-v4-1-f470ac79e2e2@nvidia.com
[ Link `None`, `Some`, `Option` in doc-comment. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-22 17:20:28 +02:00
Benno Lossin
39051adb07 rust: pin-init: examples: use allow instead of expect
Rust 1.78 doesn't emit a `dead_code` error on the annotated element,
resulting in the `unfulfilled_lint_expectations` error. Rust 1.85 does
emit the `dead_code` error, so we still need an `allow`.

Link: 0e28cbb895
Link: https://lore.kernel.org/all/20250414195928.129040-4-benno.lossin@proton.me
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
2025-04-21 23:19:22 +02:00
Benno Lossin
5c4167b405 rust: pin-init: examples: conditionally enable feature(lint_reasons)
`lint_reasons` is unstable in Rust 1.80 and earlier, enable it
conditionally in the examples to allow compiling them with older
compilers.

Link: ec494fe686
Link: https://lore.kernel.org/all/20250414195928.129040-3-benno.lossin@proton.me
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
2025-04-21 23:19:12 +02:00
Benno Lossin
31005209b8 rust: pin-init: internal: skip rustfmt formatting of kernel-only module
The `quote` module only is available in the kernel and thus running
`cargo fmt` or `rustfmt internal/src/lib.rs` in the user-space
repository [1] results in:

    error: couldn't read `~/pin-init/internal/src/../../../macros/quote.rs`: No such file or directory (os error 2)
      --> ~/pin-init/internal/src/lib.rs:25:1
       |
    25 | mod quote;
       | ^^^^^^^^^^

    Error writing files: failed to resolve mod `quote`: ~/pin-init/internal/src/../../../macros/quote.rs does not exist

Thus mark it with `rustfmt::skip` when compiling without kernel support.

Link: https://github.com/Rust-for-Linux/pin-init [1]
Link: a6caf1945e
Link: https://lore.kernel.org/all/20250414195928.129040-2-benno.lossin@proton.me
Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
2025-04-21 23:18:42 +02:00
Benno Lossin
2cce50f5ab rust: pin-init: synchronize README.md
The upstream version of the `README.md` differs by this change, so
synchronize it.

The reason that this wasn't in the original sync patch is that this was
a late change that I didn't port back to the kernel repo, since it was
generated by `cargo rdme`.

Link: https://lore.kernel.org/all/20250416225002.25253-1-benno.lossin@proton.me
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
2025-04-21 23:07:27 +02:00
Danilo Krummrich
0d1803d25f rust: auxiliary: add auxiliary registration
Implement the `auxiliary::Registration` type, which provides an API to
create and register new auxiliary devices in the system.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250414131934.28418-5-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-19 10:54:46 +02:00
Danilo Krummrich
ce735e73dd rust: auxiliary: add auxiliary device / driver abstractions
Implement the basic auxiliary abstractions required to implement a
driver matching an auxiliary device.

The design and implementation is analogous to PCI and platform and is
based on the generic device / driver abstractions.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250414131934.28418-4-dakr@kernel.org
[ Fix typos, `let _ =` => `drop()`, use `kernel::ffi`. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-19 10:54:25 +02:00
Danilo Krummrich
a4c9f71e34 rust: device: implement Device::parent()
Device::parent() returns a reference to the device' parent device, if
any.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250414131934.28418-3-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-19 10:41:28 +02:00
Danilo Krummrich
9647b6c509 rust: types: add Opaque::zeroed
Analogous to `Opaque::uninit` add `Opaque::zeroed`, which sets the
corresponding memory to zero. In contrast to `Opaque::uninit`, the
corresponding value, depending on its type, may be initialized.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250414131934.28418-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-19 10:41:28 +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
a095d0d1e4 rust: pci: impl TryFrom<&Device> for &pci::Device
Implement TryFrom<&device::Device> for &Device.

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

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250321214826.140946-3-dakr@kernel.org
[ Support device context types, use dev_is_pci() helper. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-19 10:20:16 +02:00
Danilo Krummrich
7bd1710aac rust: dma: require a bound device
Require the Bound device context to be able to create new
dma::CoherentAllocation instances.

DMA memory allocations are only valid to be created for bound devices.

Link: https://lore.kernel.org/r/20250413173758.12068-10-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:54 +02:00
Danilo Krummrich
f720efda2d rust: devres: require a bound device
Require the Bound device context to be able to a new Devres container.
This ensures that we can't register devres callbacks for unbound
devices.

Link: https://lore.kernel.org/r/20250413173758.12068-9-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:52 +02:00
Danilo Krummrich
f2a399d7b6 rust: pci: move iomap_region() to impl Device<Bound>
Require the Bound device context to be able to call iomap_region() and
iomap_region_sized(). Creating I/O mapping requires the device to be
bound.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-8-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:50 +02:00
Danilo Krummrich
f933b7489f rust: device: implement Bound device context
The Bound device context indicates that a device is bound to a driver.
It must be used for APIs that require the device to be bound, such as
Devres or dma::CoherentAllocation.

Implement Bound and add the corresponding Deref hierarchy, as well as the
corresponding ARef conversion for this device context.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-7-dakr@kernel.org
[ Add missing `::` prefix in macros. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:48 +02:00
Danilo Krummrich
3edaefbf2b rust: pci: preserve device context in AsRef
Since device::Device has a generic over its context, preserve this
device context in AsRef.

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

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-6-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:47 +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
d32e4c24a7 rust: device: implement device context for Device
Analogous to bus specific device, implement the DeviceContext generic
for generic devices.

This is used for APIs that work with generic devices (such as Devres) to
evaluate the device's context.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-4-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-17 15:21:39 +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
FUJITA Tomonori
c1b4071ec3 rust: helpers: Add dma_alloc_attrs() and dma_free_attrs()
Add dma_alloc_attrs() and dma_free_attrs() helpers to fix a build
error when CONFIG_HAS_DMA is not enabled.

Note that when CONFIG_HAS_DMA is enabled, dma_alloc_attrs() and
dma_free_attrs() are included in both bindings_generated.rs and
bindings_helpers_generated.rs. The former takes precedence so behavior
remains unchanged in that case.

This fixes the following build error on UML:

error[E0425]: cannot find function `dma_alloc_attrs` in crate `bindings`
     --> rust/kernel/dma.rs:171:23
      |
171   |               bindings::dma_alloc_attrs(
      |                         ^^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_alloc_pages`
      |
     ::: rust/bindings/bindings_generated.rs:44568:5
      |
44568 | /     pub fn dma_alloc_pages(
44569 | |         dev: *mut device,
44570 | |         size: usize,
44571 | |         dma_handle: *mut dma_addr_t,
44572 | |         dir: dma_data_direction,
44573 | |         gfp: gfp_t,
44574 | |     ) -> *mut page;
      | |___________________- similarly named function `dma_alloc_pages` defined here

error[E0425]: cannot find function `dma_free_attrs` in crate `bindings`
     --> rust/kernel/dma.rs:293:23
      |
293   |               bindings::dma_free_attrs(
      |                         ^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_free_pages`
      |
     ::: rust/bindings/bindings_generated.rs:44577:5
      |
44577 | /     pub fn dma_free_pages(
44578 | |         dev: *mut device,
44579 | |         size: usize,
44580 | |         page: *mut page,
44581 | |         dma_handle: dma_addr_t,
44582 | |         dir: dma_data_direction,
44583 | |     );
      | |______- similarly named function `dma_free_pages` defined here

Fixes: ad2907b4e3 ("rust: add dma coherent allocator abstraction")
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250412000507.157000-1-fujita.tomonori@gmail.com
[ Reworded for relative paths. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-04-15 23:06:03 +02:00
FUJITA Tomonori
584e61452f rust: helpers: Remove volatile qualifier from io helpers
Remove the `volatile` qualifier used with __iomem in helper functions
in io.c. These helper functions are just wrappers around the
corresponding accessors so they are unnecessary.

This fixes the following UML build error with CONFIG_RUST enabled:

In file included from rust/helpers/helpers.c:19:
rust/helpers/io.c:12:10: error: passing 'volatile void *' to parameter of type 'void *' discards qualifiers [-Werror,-Wincompatible-pointer-types-discards-qualifiers]
   12 |         iounmap(addr);
      |                 ^~~~
arch/um/include/asm/io.h:19:42: note: passing argument to parameter 'addr' here
   19 | static inline void iounmap(void __iomem *addr)
      |                                          ^
1 error generated.

[ Arnd explains [1] that removing the qualifier is the way forward
  (thanks!):

    Rihgt, I tried this last week when it came up first, removing the
    'volatile' annotations in the asm-generic/io.h header and then
    all the ones that caused build regressions on arm/arm64/x86
    randconfig and allmodconfig builds.  This patch is a little
    longer than my original version as I did run into a few
    regressions later.

    As far as I can tell, none of these volatile annotations have
    any actual effect, and most of them date back to ancient kernels
    where this may have been required.

    Leaving it out of the rust interface is clearly the right way,
    and it shouldn't be too hard to upstream the changes below
    when we need to, but I also don't see any priority to send these.
    If anyone wants to help out, I can send them the whole patch.

  I created an issue [2] in case someone wants to help. - Miguel ]

Fixes: ce30d94e68 ("rust: add `io::{Io, IoRaw}` base types")
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/rust-for-linux/0c844b70-19c7-4b14-ba29-fc99ae0d69f0@app.fastmail.com/ [1]
Link: https://github.com/Rust-for-Linux/linux/issues/1156 [2]
Link: https://lore.kernel.org/r/20250412005341.157150-1-fujita.tomonori@gmail.com
[ Reworded for relative paths. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-04-15 23:03:00 +02:00
Christian Schrefl
53bd978016 rust: firmware: Use ffi::c_char type in FwFunc
The `FwFunc` struct contains an function with a char pointer argument,
for which a `*const u8` pointer was used. This is not really the
"proper" type for this, so use a `*const kernel::ffi::c_char` pointer
instead.

This has no real functionality changes, since now `kernel::ffi::c_char`
(which bindgen uses for `char`) is now a type alias to `u8` anyways,
but before commit 1bae8729e5 ("rust: map `long` to `isize` and `char`
to `u8`") the concrete type of `kernel::ffi::c_char` depended on the
architecture (However all supported architectures at the time mapped to
`i8`).

This caused problems on the v6.13 tag when building for 32 bit arm (with
my patches), since back then `*const i8` was used in the function
argument and the function that bindgen generated used
`*const core::ffi::c_char` which Rust mapped to `*const u8` on 32 bit
arm. The stable v6.13.y branch does not have this issue since commit
1bae8729e5 ("rust: map `long` to `isize` and `char` to `u8`") was
backported.

This caused the following build error:
```
error[E0308]: mismatched types
  --> rust/kernel/firmware.rs:20:4
   |
20 |         Self(bindings::request_firmware)
   |         ---- ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected fn pointer, found fn item
   |         |
   |         arguments to this function are incorrect
   |
   = note: expected fn pointer `unsafe extern "C" fn(_, *const i8, _) -> _`
                 found fn item `unsafe extern "C" fn(_, *const u8, _) -> _ {request_firmware}`
note: tuple struct defined here
  --> rust/kernel/firmware.rs:14:8
   |
14 | struct FwFunc(
   |        ^^^^^^

error[E0308]: mismatched types
  --> rust/kernel/firmware.rs:24:14
   |
24 |         Self(bindings::firmware_request_nowarn)
   |         ---- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected fn pointer, found fn item
   |         |
   |         arguments to this function are incorrect
   |
   = note: expected fn pointer `unsafe extern "C" fn(_, *const i8, _) -> _`
                 found fn item `unsafe extern "C" fn(_, *const u8, _) -> _ {firmware_request_nowarn}`
note: tuple struct defined here
  --> rust/kernel/firmware.rs:14:8
   |
14 | struct FwFunc(
   |        ^^^^^^

error[E0308]: mismatched types
  --> rust/kernel/firmware.rs:64:45
   |
64 |         let ret = unsafe { func.0(pfw as _, name.as_char_ptr(), dev.as_raw()) };
   |                            ------           ^^^^^^^^^^^^^^^^^^ expected `*const i8`, found `*const u8`
   |                            |
   |                            arguments to this function are incorrect
   |
   = note: expected raw pointer `*const i8`
              found raw pointer `*const u8`

error: aborting due to 3 previous errors
```

Fixes: de6582833d ("rust: add firmware abstractions")
Cc: stable@vger.kernel.org
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250413-rust_arm_fix_fw_abstaction-v3-1-8dd7c0bbcd47@gmail.com
[ Add firmware prefix to commit subject. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-14 14:13:23 +02:00
Sami Tolvanen
c59026c057 rust: kbuild: Don't export __pfx symbols
With CONFIG_PREFIX_SYMBOLS, objtool adds __pfx prefix symbols
to claim the compiler emitted call padding bytes. When
CONFIG_X86_KERNEL_IBT is not selected, the symbols are added to
individual object files and for Rust objects, they end up being
exported, resulting in warnings with CONFIG_GENDWARFKSYMS as the
symbols have no debugging information:

warning: gendwarfksyms: symbol_print_versions: no information for symbol __pfx_rust_helper_put_task_struct
warning: gendwarfksyms: symbol_print_versions: no information for symbol __pfx_rust_helper_task_euid
warning: gendwarfksyms: symbol_print_versions: no information for symbol __pfx_rust_helper_readq_relaxed
...

Filter out the __pfx prefix from exported symbols similarly to
the existing __cfi and __odr_asan prefixes.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Cc: stable@vger.kernel.org
Fixes: ac61506bf2 ("rust: Use gendwarfksyms + extended modversions for CONFIG_MODVERSIONS")
Link: https://lore.kernel.org/r/20250318231815.917621-2-samitolvanen@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-04-08 21:44:20 +02:00
Miguel Ojeda
193b5a7574 rust: pin-init: use Markdown autolinks in Rust comments
"Normal" comments in Rust (`//`) are also formatted in Markdown, like
the documentation (`///` and `//!`), see
Documentation/rust/coding-guidelines.rst

Thus use Markdown autolinks for a couple links that were missing it.

It also helps to get proper linking in some software like kitty [1].

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://github.com/Rust-for-Linux/pin-init/pull/32#discussion_r2023103712 [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: dd230d61bf
Fixes: 84837cf6fa ("rust: pin-init: change examples to the user-space version")
Cc: stable@vger.kernel.org
[ Change case in title. Reworded commit message. - Benno ]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250407201755.649153-3-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-04-08 21:12:58 +02:00
Miguel Ojeda
3c75fff196 rust: pin-init: alloc: restrict impl ZeroableOption for Box to T: Sized
Similar to what was done for `Zeroable<NonNull<T>>` in commit
df27cef153 ("rust: init: fix `Zeroable` implementation for
`Option<NonNull<T>>` and `Option<KBox<T>>`"), the latest Rust
documentation [1] says it guarantees that `transmute::<_,
Option<T>>([0u8; size_of::<T>()])` is sound and produces
`Option::<T>::None` only in some cases. In particular, it says:

    `Box<U>` (specifically, only `Box<U, Global>`) when `U: Sized`

Thus restrict the `impl` to `Sized`, and use similar wording as in that
commit too.

Link: https://doc.rust-lang.org/stable/std/option/index.html#representation [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: a6007cf555
Fixes: 9b2299af3b ("rust: pin-init: add `std` and `alloc` support from the user-space version")
Cc: stable@vger.kernel.org
[ Adjust mentioned commit to the one from the kernel. - Benno ]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250407201755.649153-2-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-04-08 21:12:58 +02:00
Tamir Duberstein
c3152988c0 rust: alloc: use spare_capacity_mut to reduce unsafe
Use `spare_capacity_mut` in the implementation of `push` to reduce the
use of `unsafe`. Both methods were added in commit 2aac4cd7da ("rust:
alloc: implement kernel `Vec` type").

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250318-vec-push-use-spare-v3-1-68741671d1af@gmail.com
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-07 16:59:06 +02:00
Andrew Ballance
1679b71593 rust: alloc: add Vec::resize method
Implement the equivalent of the rust std's Vec::resize on the kernel's
Vec type.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250316111644.154602-3-andrewjballance@gmail.com
Signed-off-by: Andrew Ballance <andrewjballance@gmail.com>
[ Use checked_sub(), as suggested by Tamir. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-07 14:41:10 +02:00
Andrew Ballance
81e1c4dab5 rust: alloc: add Vec::truncate method
Implement the equivalent to the std's Vec::truncate on the kernel's Vec
type.

Link: https://lore.kernel.org/r/20250316111644.154602-2-andrewjballance@gmail.com
Signed-off-by: Andrew Ballance <andrewjballance@gmail.com>
[ Rewrote safety comment of set_len(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-07 14:38:02 +02:00
Danilo Krummrich
fb1bf1067d rust: alloc: add missing invariant in Vec::set_len()
When setting a new length, we have to justify that the set length
represents the exact number of elements stored in the vector.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reported-by: Alice Ryhl <aliceryhl@google.com>
Closes: https://lore.kernel.org/rust-for-linux/20250311-iov-iter-v1-4-f6c9134ea824@google.com
Fixes: 2aac4cd7da ("rust: alloc: implement kernel `Vec` type")
Link: https://lore.kernel.org/r/20250315154436.65065-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-07 14:02:56 +02:00
Linus Torvalds
f4d2ef4825 Merge tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

 - Improve performance in gendwarfksyms

 - Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS

 - Support CONFIG_HEADERS_INSTALL for ARCH=um

 - Use more relative paths to sources files for better reproducibility

 - Support the loong64 Debian architecture

 - Add Kbuild bash completion

 - Introduce intermediate vmlinux.unstripped for architectures that need
   static relocations to be stripped from the final vmlinux

 - Fix versioning in Debian packages for -rc releases

 - Treat missing MODULE_DESCRIPTION() as an error

 - Convert Nios2 Makefiles to use the generic rule for built-in DTB

 - Add debuginfo support to the RPM package

* tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
  kbuild: rpm-pkg: build a debuginfo RPM
  kconfig: merge_config: use an empty file as initfile
  nios2: migrate to the generic rule for built-in DTB
  rust: kbuild: skip `--remap-path-prefix` for `rustdoc`
  kbuild: pacman-pkg: hardcode module installation path
  kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally
  modpost: require a MODULE_DESCRIPTION()
  kbuild: make all file references relative to source root
  x86: drop unnecessary prefix map configuration
  kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS
  kbuild: Add a help message for "headers"
  kbuild: deb-pkg: remove "version" variable in mkdebian
  kbuild: deb-pkg: fix versioning for -rc releases
  Documentation/kbuild: Fix indentation in modules.rst example
  x86: Get rid of Makefile.postlink
  kbuild: Create intermediate vmlinux build with relocations preserved
  kbuild: Introduce Kconfig symbol for linking vmlinux with relocations
  kbuild: link-vmlinux.sh: Make output file name configurable
  kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y
  Revert "kheaders: Ignore silly-rename files"
  ...
2025-04-05 15:46:50 -07:00
Linus Torvalds
e8b4712852 Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux
Pull ARM and clkdev updates from Russell King:

 - Simplify ARM_MMU_KEEP usage

 - Add Rust support for ARM architecture version 7

 - Align IPIs reported in /proc/interrupts

 - require linker to support KEEP within OVERLAY

 - add KEEP() for ARM vectors

 - add __printf() attribute for clkdev functions

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
  ARM: 9445/1: clkdev: Mark some functions with __printf() attribute
  ARM: 9444/1: add KEEP() keyword to ARM_VECTORS
  ARM: 9443/1: Require linker to support KEEP within OVERLAY for DCE
  ARM: 9442/1: smp: Fix IPI alignment in /proc/interrupts
  ARM: 9441/1: rust: Enable Rust support for ARMv7
  ARM: 9439/1: arm32: simplify ARM_MMU_KEEP usage
2025-04-03 12:21:44 -07:00