After initializing a field in an initializer macro, create a variable
holding a reference that points at that field. The type is either
`Pin<&mut T>` or `&mut T` depending on the field's structural pinning
kind.
[ Applied fixes to devres and rust_driver_pci sample - Benno]
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Benno Lossin <lossin@kernel.org>
Make the `#[pin_data]` macro generate a `*Projection` struct that holds
either `Pin<&mut Field>` or `&mut Field` for every field of the original
struct. Which version is chosen depends on weather there is a `#[pin]`
or not respectively. Access to this projected version is enabled through
generating `fn project(self: Pin<&mut Self>) -> SelfProjection<'_>`.
[ Adapt workqueue to use the new projection instead of its own, custom
one - Benno ]
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Benno Lossin <lossin@kernel.org>
The next commit makes the `#[pin_data]` attribute generate a `project`
function that would collide with any existing ones.
Signed-off-by: Benno Lossin <lossin@kernel.org>
When running this example with no cargo features enabled, the compiler
warns on 1.89:
error: struct `Error` is never constructed
--> examples/error.rs:11:12
|
11 | pub struct Error;
| ^^^^^
|
= note: `-D dead-code` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(dead_code)]`
Thus use the error in the main function to avoid this warning.
Signed-off-by: Benno Lossin <lossin@kernel.org>
Add a Rust driver for ARM Mali CSF-based GPUs. It is a port of Panthor
and therefore exposes Panthor's uAPI and name to userspace, and the
product of a joint effort between Collabora, Arm and Google engineers.
The aim is to incrementally develop Tyr with the abstractions that are
currently available until it is consider to be in parity with Panthor
feature-wise.
The development of Tyr itself started in January, after a few failed
attempts of converting Panthor piecewise through a mix of Rust and C
code. There is a downstream branch that's much further ahead in terms of
capabilities than this initial patch.
The downstream code is capable of booting the MCU, doing sync VM_BINDS
through the work-in-progress GPUVM abstraction and also doing (trivial)
submits through Asahi's drm_scheduler and dma_fence abstractions. So
basically, most of what one would expect a modern GPU driver to do,
except for power management and some other very important adjacent
pieces. It is not at the point where submits can correctly deal with
dependencies, or at the point where it can rotate access to the GPU
hardware fairly through a software scheduler, but that is simply a
matter of writing more code.
This first patch, however, only implements a subset of the current
features available downstream, as the rest is not implementable without
pulling in even more abstractions. In particular, a lot of things depend
on properly mapping memory on a given VA range, which itself depends on
the GPUVM abstraction that is currently work-in-progress. For this
reason, we still cannot boot the MCU and thus, cannot do much for the
moment.
This constitutes a change in the overall strategy that we have been
using to develop Tyr so far. By submitting small parts of the driver
upstream iteratively, we aim to:
a) evolve together with Nova and rvkms, hopefully reducing regressions
due to upstream changes (that may break us because we were not there, in
the first place)
b) prove any work-in-progress abstractions by having them run on a real
driver and hardware and,
c) provide a reason to work on and review said abstractions by providing
a user, which would be tyr itself.
Despite its limited feature-set, we offer IGT tests. It is only tested
on the rk3588, so any other SoC is probably not going to work at all for
now.
The skeleton is basically taken from Nova and also
rust_platform_driver.rs.
Lastly, the name "Tyr" is inspired by Norse mythology, reflecting ARM's
tradition of naming their GPUs after Nordic mythological figures and
places.
Co-developed-by: Beata Michalska <beata.michalska@arm.com>
Signed-off-by: Beata Michalska <beata.michalska@arm.com>
Co-developed-by: Carsten Haitzler <carsten.haitzler@foss.arm.com>
Signed-off-by: Carsten Haitzler <carsten.haitzler@foss.arm.com>
Co-developed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://www.collabora.com/news-and-blog/news-and-events/introducing-tyr-a-new-rust-drm-driver.html
Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com>
Acked-by: Boris Brezillon <boris.brezillon@collabora.com>
[aliceryhl: minor Kconfig update on apply]
[aliceryhl: s/drm::device::/drm::/]
Link: https://lore.kernel.org/r/20250910-tyr-v3-1-dba3bc2ae623@collabora.com
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
A lot of drivers only care about enabling the regulator for as long as
the underlying Device is bound. This can be easily observed due to the
extensive use of `devm_regulator_get_enable` and
`devm_regulator_get_enable_optional` throughout the kernel.
Therefore, make this helper available in Rust. Also add an example
noting how it should be the default API unless the driver needs more
fine-grained control over the regulator.
Suggested-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://patch.msgid.link/20250910-regulator-remove-dynamic-v3-2-07af4dfa97cc@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Introduces the concept of a `ScopedDir`, which allows for the creation
of debugfs directories and files that are tied to the lifetime of a
particular data structure. This ensures that debugfs entries do not
outlive the data they refer to.
The new `Dir::scope` method creates a new directory that is owned by a
`Scope` handle. All files and subdirectories created within this scope
are automatically cleaned up when the `Scope` is dropped.
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250904-debugfs-rust-v11-6-7d12a165685a@google.com
[ Fix up Result<(), Error> -> Result; fix spurious backtick in
doc-comment. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Extends the `debugfs` API to support creating files with content
generated and updated by callbacks. This is done via the
`read_callback_file`, `write_callback_file`, and
`read_write_callback_file` methods.
These methods allow for more flexible file definition, either because
the type already has a `Writer` or `Reader` method that doesn't
do what you'd like, or because you cannot implement it (e.g. because
it's a type defined in another crate or a primitive type).
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250904-debugfs-rust-v11-4-7d12a165685a@google.com
[ Fix up Result<(), Error> -> Result. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Extends the `debugfs` API to support creating read-only files. This
is done via the `Dir::read_only_file` method, which takes a data object
that implements the `Writer` trait.
The file's content is generated by the `Writer` implementation, and the
file is automatically removed when the returned `File` handle is
dropped.
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250904-debugfs-rust-v11-2-7d12a165685a@google.com
[ Fixup build failure when CONFIG_DEBUGFS=n. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
We need the DRM Rust changes that went into drm-misc before the
existence of the drm-rust tree in here as well.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Core functions like `to_result` should have good documentation.
Thus improve it, including adding an example of how to perform early
returns with it.
Reviewed-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This constructor is public since commit 5ed1474734 ("rust: error:
make conversion functions public"), and we will refer to it from the
documentation of `to_result` in a later commit.
Thus improve its documentation, including adding examples.
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Now that my rust skills have been honed, I noticed that there's a lot of
generics in our gem bindings that don't actually need to be here. Currently
the hierarchy of traits in our gem bindings looks like this:
* Drivers implement:
* BaseDriverObject<T: DriverObject> (has the callbacks)
* DriverObject (has the drm::Driver type)
* Crate implements:
* IntoGEMObject for Object<T> where T: DriverObject
Handles conversion to/from raw object pointers
* BaseObject for T where T: IntoGEMObject
Provides methods common to all gem interfaces
Also of note, this leaves us with two different drm::Driver associated
types:
* DriverObject::Driver
* IntoGEMObject::Driver
I'm not entirely sure of the original intent here unfortunately (if anyone
is, please let me know!), but my guess is that the idea would be that some
objects can implement IntoGEMObject using a different ::Driver than
DriverObject - presumably to enable the usage of gem objects from different
drivers. A reasonable usecase of course.
However - if I'm not mistaken, I don't think that this is actually how
things would go in practice. Driver implementations are of course
implemented by their associated drivers, and generally drivers are not
linked to each-other when building the kernel. Which is to say that even in
a situation where we would theoretically deal with gem objects from another
driver, we still wouldn't have access to its drm::driver::Driver
implementation. It's more likely we would simply want a variant of gem
objects in such a situation that have no association with a
drm::driver::Driver type.
Taking that into consideration, we can assume the following:
* Anything that implements BaseDriverObject will implement DriverObject
In other words, all BaseDriverObjects indirectly have an associated
::Driver type - so the two traits can be combined into one with no
generics.
* Not everything that implements IntoGEMObject will have an associated
::Driver, and that's OK.
And with this, we now can do quite a bit of cleanup with the use of
generics here. As such, this commit:
* Removes the generics on BaseDriverObject
* Moves DriverObject::Driver into BaseDriverObject
* Removes DriverObject
* Removes IntoGEMObject::Driver
* Add AllocImpl::Driver, which we can use as a binding to figure out the
correct File type for BaseObject
Leaving us with a simpler trait hierarchy that now looks like this:
* Drivers implement: BaseDriverObject
* Crate implements:
* IntoGEMObject for Object<T> where T: DriverObject
* BaseObject for T where T: IntoGEMObject
Which makes the code a lot easier to understand and build on :).
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250908185239.135849-2-lyude@redhat.com
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
All types in `bindings` implement `Zeroable` if they can, so use
`pin_init::zeroed` instead of relying on `unsafe` code.
If this ends up not compiling in the future, something in bindgen or on
the C side changed and is most likely incorrect.
Signed-off-by: Benno Lossin <lossin@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Using the `--with-derive-custom-{struct,union}` option of bindgen, add
`#[derive(MaybeZeroable)]` to every struct & union. This makes those
types implement `Zeroable` if all their fields implement it.
Sadly bindgen doesn't add custom derives to the `__BindgenBitfieldUnit`
struct. So manually implement `Zeroable` for that.
Signed-off-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The error codes come from several headers.
Thus, add the other header links.
Signed-off-by: Onur Özkan <work@onurozkan.dev>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
[ Sorted headers. Added line breaks. Reworded commit message. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`srctree/` links may point to nonexistent files, e.g. due to renames
that missed to update the files or simply because of typos.
Since they can be easily checked for validity, do so and print a warning
in the file does not exist.
This found the following cases already in-tree:
warning: srctree/ link to include/linux/blk_mq.h does not exist
warning: srctree/ link to include/linux/drm/drm_gem.h does not exist
warning: srctree/ link to include/linux/drm/drm_drv.h does not exist
warning: srctree/ link to include/linux/drm/drm_ioctl.h does not exist
warning: srctree/ link to include/linux/drm/drm_file.h does not exist
warning: srctree/ link to include/linux/drm/drm_device.h does not exist
Inspired-by: Onur Özkan <work@onurozkan.dev>
Link: https://lore.kernel.org/rust-for-linux/CANiq72=xCYA7z7_rxpzzKkkhJs6m7L_xEaLMuArVn3ZAcyeHdA@mail.gmail.com/
Reviewed-by: Onur Özkan <work@onurozkan.dev>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This `srctree/` link pointed to a file with an underscore, but the header
used a dash instead.
Thus fix it.
This cleans a future warning that will check our `srctree/` links.
Cc: stable@vger.kernel.org
Fixes: 3253aba340 ("rust: block: introduce `kernel::block::mq` module")
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull alloc and DMA updates from Danilo Krummrich:
Allocator:
- Provide information about the minimum alignment guarantees of
'Kmalloc', 'Vmalloc' and 'KVmalloc'.
- Take minimum alignment guarantees of allocators for
'ForeignOwnable' into account.
- Remove the 'allocator_test' incl. 'Cmalloc'.
Box:
- Implement 'Box::pin_slice()', which constructs a pinned slice of
elements.
Vec:
- Simplify KUnit test module name to 'rust_kvec'.
- Add doc-test for 'Vec::as_slice()'.
- Constify various methods.
DMA:
- Update 'ARef' and 'AlwaysRefCounted' imports.
MISC:
- Remove support for unused host '#[test]'s.
- Constify 'ArrayLayout::new_unchecked()'.
* tag 'alloc-next-v6.18-2025-09-04' of https://github.com/Rust-for-Linux/linux:
rust: alloc: remove `allocator_test`
rust: kernel: remove support for unused host `#[test]`s
rust: alloc: implement Box::pin_slice()
rust: alloc: add ARCH_KMALLOC_MINALIGN to bindgen blocklist
rust: dma: Update ARef and AlwaysRefCounted imports from sync::aref
rust: alloc: take the allocator into account for FOREIGN_ALIGN
rust: alloc: specify the minimum alignment of each allocator
rust: make `kvec::Vec` functions `const fn`
rust: make `ArrayLayout::new_unchecked` a `const fn`
rust: alloc: kvec: simplify KUnit test module name to "rust_kvec"
rust: alloc: kvec: add doc example for as_slice method
Pull rust fixes from Miguel Ojeda:
- Two changes to prepare for the future Rust 1.91.0 release (expected
2025-10-30, currently in nightly): a target specification format
change and a renamed, soon-to-be-stabilized 'core' function.
* tag 'rust-fixes-6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
rust: support Rust >= 1.91.0 target spec
rust: use the new name Location::file_as_c_str() in Rust >= 1.91.0
Alice Ryhl <aliceryhl@google.com> says:
This series adds support for the `struct iov_iter` type. This type
represents an IO buffer for reading or writing, and can be configured
for either direction of communication.
In Rust, we define separate types for reading and writing. This will
ensure that you cannot mix them up and e.g. call copy_from_iter in a
read_iter syscall.
To use the new abstractions, miscdevices are given new methods read_iter
and write_iter that can be used to implement the read/write syscalls on
a miscdevice. The miscdevice sample is updated to provide read/write
operations.
Intended for Greg's miscdevice tree.
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-0-6ce4819c2977@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds abstractions for the iov_iter type in the case where
data_source is ITER_DEST. This will make Rust implementations of
fops->read_iter possible.
This series only has support for using existing IO vectors created by C
code. Additional abstractions will be needed to support the creation of
IO vectors in Rust code.
These abstractions make the assumption that `struct iov_iter` does not
have internal self-references, which implies that it is valid to move it
between different local variables.
This patch adds an IovIterDest struct that is very similar to the
IovIterSource from the previous patch. However, as the methods on the
two structs have very little overlap (just getting the length and
advance/revert), I do not think it is worth it to try and deduplicate
this logic.
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-2-6ce4819c2977@google.com
This adds abstractions for the iov_iter type in the case where
data_source is ITER_SOURCE. This will make Rust implementations of
fops->write_iter possible.
This series only has support for using existing IO vectors created by C
code. Additional abstractions will be needed to support the creation of
IO vectors in Rust code.
These abstractions make the assumption that `struct iov_iter` does not
have internal self-references, which implies that it is valid to move it
between different local variables.
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-1-6ce4819c2977@google.com
Merge series from Woodrow Douglass <wdouglass@carnegierobotics.com>:
I wrote this driver to read settings and state from the nxp pf530x
regulator. Please consider it for inclusion, any criticism is welcome.
Add a safe Rust abstraction for the kernel's scatter-gather list
facilities (`struct scatterlist` and `struct sg_table`).
This commit introduces `SGTable<T>`, a wrapper that uses a generic
parameter to provide compile-time guarantees about ownership and lifetime.
The abstraction provides two primary states:
- `SGTable<Owned<P>>`: Represents a table whose resources are fully
managed by Rust. It takes ownership of a page provider `P`, allocates
the underlying `struct sg_table`, maps it for DMA, and handles all
cleanup automatically upon drop. The DMA mapping's lifetime is tied to
the associated device using `Devres`, ensuring it is correctly unmapped
before the device is unbound.
- `SGTable<Borrowed>` (or just `SGTable`): A zero-cost representation of
an externally managed `struct sg_table`. It is created from a raw
pointer using `SGTable::from_raw()` and provides a lifetime-bound
reference (`&'a SGTable`) for operations like iteration.
The API exposes a safe iterator that yields `&SGEntry` references,
allowing drivers to easily access the DMA address and length of each
segment in the list.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Co-developed-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Link: https://lore.kernel.org/r/20250828133323.53311-4-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Introduce the VmallocPageIter type; an instance of VmallocPageIter may
be exposed by owners of vmalloc allocations to provide borrowed access
to its backing pages.
For instance, this is useful to access and borrow the backing pages of
allocation primitives, such as Box and Vec, backing a scatterlist.
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Suggested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250820145434.94745-4-dakr@kernel.org
[ Drop VmallocPageIter::base_address(), move to allocator/iter.rs and
stub VmallocPageIter for allocator_test.rs. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Merge OPP (operating performance points) updates for 6.18 from Viresh
Kumar:
"- Add support to find OPP for a set of keys (Krishna Chaitanya Chundru).
- Minor optimization to OPP Rust implementation (Onur Özkan)."
* tag 'opp-updates-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
OPP: Add support to find OPP for a set of keys
rust: opp: use to_result for error handling
Merge CPUFreq updates for 6.18 from Viresh Kumar:
"- Minor improvements to Rust Cpumask APIs (Alice Ryhl, Baptiste Lepers,
and Shankari Anand).
- Minor cleanups and optimizations to various cpufreq drivers (Akhilesh
Patil, BowenYu, Dennis Beier, Liao Yuanhong, Zihuan Zhang, Florian
Fainelli, Taniya Das, Md Sadre Alam, and Christian Marangi).
- Enhancements for TI cpufreq driver (Judith Mendez, and Paresh Bhagat).
- Enhancements for mediatek cpufreq driver (Nicolas Frattaroli).
- Remove outdated cpufreq-dt.txt (Frank Li).
- Update MAINTAINERS for virtual-cpufreq maintainer (Saravana Kannan)."
* tag 'cpufreq-arm-updates-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: (28 commits)
cpufreq: mediatek: avoid redundant conditions
cpufreq/longhaul: handle NULL policy in longhaul_exit
cpufreq: tegra186: Use scope-based cleanup helper
cpufreq: mediatek: Use scope-based cleanup helper
cpufreq: s5pv210: Use scope-based cleanup helper
cpufreq: CPPC: Use scope-based cleanup helper
cpufreq: brcmstb-avs: Use scope-based cleanup helper
dt-bindings: Remove outdated cpufreq-dt.txt
arm64: dts: ti: k3-am62p: Fix supported hardware for 1GHz OPP
cpufreq: ti: Allow all silicon revisions to support OPPs
cpufreq: ti: Support more speed grades on AM62Px SoC
cpufreq: ti: Add support for AM62D2
cpufreq: dt-platdev: Blacklist ti,am62d2 SoC
rust: opp: update ARef and AlwaysRefCounted imports from sync::aref
cpufreq: mediatek-hw: don't use error path on NULL fdvfs
cpufreq: scmi: Account for malformed DT in scmi_dev_used_by_cpus()
rust: cpumask: Mark CpumaskVar as transparent
rust: cpumask: rename CpumaskVar::as[_mut]_ref to from_raw[_mut]
dt-bindings: cpufreq: cpufreq-qcom-hw: Add QCS615 compatible
MAINTAINERS: Add myself as virtual-cpufreq maintainer
...
