This is needed to inline these helpers into Rust code.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-19-51da5f454a67@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is needed to inline these helpers into Rust code.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-12-51da5f454a67@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is needed to inline these helpers into Rust code.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-11-51da5f454a67@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is needed to inline these helpers into Rust code.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Andrew Ballance <andrewjballance@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-10-51da5f454a67@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is needed to inline these helpers into Rust code.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-8-51da5f454a67@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is needed to inline these helpers into Rust code.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-3-51da5f454a67@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is useful when using types that may or may not be empty in generic
code relying on these traits. It is also safe because technically a
no-op.
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://patch.msgid.link/20251215-transmute_unit-v4-1-477d71ec7c23@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Some doc comments use `NULL` while others use plain NULL. Make it
consistent by adding backticks everywhere, matching the majority of
existing usage.
Signed-off-by: Peter Novak <seimun018r@gmail.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: David Gow <davidgow@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20251130211233.367946-1-seimun018r@gmail.com
[ Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Following commit 3a1ec424dd ("rust: num: bounded: mark __new as
unsafe"), remove the redundant paragraph in the documentation of __new now
that the Safety section explicitly covers the requirement.
Additionally, add an INVARIANT comment inside the function body where
the Bounded instance is actually constructed to document that the type
invariant is upheld.
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/rust-for-linux/CANiq72mUCUh72BWP4eD1PTDpwdb1ML+Xgfom-Ys6thJooqQPwQ@mail.gmail.com/
Signed-off-by: Shivam Kalra <shivamklr@cock.li>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260123132132.53854-1-shivamklr@cock.li
[ Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
For arm32, on a x86_64 builder, running the `rusttest` target yields:
error[E0080]: evaluation of constant value failed
--> rust/kernel/static_assert.rs:37:23
|
37 | const _: () = ::core::assert!($condition $(,$arg)?);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'assertion failed: size_of::<isize>() == size_of::<isize_atomic_repr>()', rust/kernel/sync/atomic/predefine.rs:68:1
|
::: rust/kernel/sync/atomic/predefine.rs:68:1
|
68 | static_assert!(size_of::<isize>() == size_of::<isize_atomic_repr>());
| -------------------------------------------------------------------- in this macro invocation
|
= note: this error originates in the macro `::core::assert` which comes from the expansion of the macro `static_assert` (in Nightly builds, run with -Z macro-backtrace for more info)
The reason is that `rusttest` runs on the host, so for e.g. a x86_64
builder `isize` is 64 bits but it is not a `CONFIG_64BIT` build.
Fix it by providing a stub for `rusttest` as usual.
Fixes: 84c6d36bca ("rust: sync: atomic: Add Atomic<{usize,isize}>")
Cc: stable@vger.kernel.org
Reviewed-by: Onur Özkan <work@onurozkan.dev>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20260123233432.22703-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
- Always inline I/O and IRQ methods using build_assert!() to avoid
false positive build errors.
- Do not free the driver's device private data in I2C shutdown()
avoiding race conditions that can lead to UAF bugs.
- Drop the driver's device private data after the driver has been
fully unbound from its device to avoid UAF bugs from &Device<Bound>
scopes, such as IRQ callbacks.
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Merge tag 'driver-core-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core fixes from Danilo Krummrich:
- Always inline I/O and IRQ methods using build_assert!() to avoid
false positive build errors
- Do not free the driver's device private data in I2C shutdown()
avoiding race conditions that can lead to UAF bugs
- Drop the driver's device private data after the driver has been
fully unbound from its device to avoid UAF bugs from &Device<Bound>
scopes, such as IRQ callbacks
* tag 'driver-core-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
rust: driver: drop device private data post unbind
rust: driver: add DriverData type to the DriverLayout trait
rust: driver: add DEVICE_DRIVER_OFFSET to the DriverLayout trait
rust: driver: introduce a DriverLayout trait
rust: auxiliary: add Driver::unbind() callback
rust: i2c: do not drop device private data on shutdown()
rust: irq: always inline functions using build_assert with arguments
rust: io: always inline functions using build_assert with arguments
Currently, `dev_*` only works on the core `Device`, but not on any other
bus or class device objects. This causes a pattern of
`dev_info!(pdev.as_ref())` which is not ideal.
This adds support of using these devices directly with `dev_*` macros, by
adding `AsRef` call inside the macro. To make sure we can still use just
`kernel::device::Device`, as `AsRef` implementation is added for it; this
is typical for types that is designed to use with `AsRef` anyway, for
example, `str` implements `AsRef<str>` and `Path` implements `AsRef<Path>`.
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260123175854.176735-1-gary@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Drivers might need to access PCI config space for querying capability
structures and access the registers inside the structures.
For Rust drivers need to access PCI config space, the Rust PCI abstraction
needs to support it in a way that upholds Rust's safety principles.
Introduce a `ConfigSpace` wrapper in Rust PCI abstraction to provide safe
accessors for PCI config space. The new type implements the `Io` trait and
`IoCapable<T>` for u8, u16, and u32 to share offset validation and
bound-checking logic with other I/O backends.
The `ConfigSpace` type uses marker types (`Normal` and `Extended`) to
represent configuration space sizes at the type level.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/all/DFV4IJDQC2J6.1Q91JOAL6CJSG@kernel.org/ [1]
Link: https://patch.msgid.link/20260121202212.4438-5-zhiw@nvidia.com
[ Applied the diff from [1], considering subsequent comment; remove
#[expect(unused)] from define_{read,write}!(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Refactor the existing MMIO accessors to use common call macros
instead of inlining the bindings calls in each `define_{read,write}!`
expansion.
This factoring separates the common offset/bounds checks from the
low-level call pattern, making it easier to add additional I/O accessor
families.
No functional change intended.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260121202212.4438-4-zhiw@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The previous Io<SIZE> type combined both the generic I/O access helpers
and MMIO implementation details in a single struct. This coupling prevented
reusing the I/O helpers for other backends, such as PCI configuration
space.
Establish a clean separation between the I/O interface and concrete
backends by separating generic I/O helpers from MMIO implementation.
Introduce a new trait hierarchy to handle different access capabilities:
- IoCapable<T>: A marker trait indicating that a backend supports I/O
operations of a certain type (u8, u16, u32, or u64).
- Io trait: Defines fallible (try_read8, try_write8, etc.) and infallibile
(read8, write8, etc.) I/O methods with runtime bounds checking and
compile-time bounds checking.
- IoKnownSize trait: The marker trait for types support infallible I/O
methods.
Move the MMIO-specific logic into a dedicated Mmio<SIZE> type that
implements the Io traits. Rename IoRaw to MmioRaw and update consumers to
use the new types.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260121202212.4438-3-zhiw@nvidia.com
[ Add #[expect(unused)] to define_{read,write}!(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Looks like we've actually had a malformed rustdoc reference in the rustdocs
for Registration::new_foreign_owned() for a while that, when fixed, still
couldn't resolve properly because it refers to a private item.
This is probably leftover from when Registration::new() was public, so drop
the documentation from that function and fixup the documentation for
Registration::new_foreign_owned().
Signed-off-by: Lyude Paul <lyude@redhat.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Fixes: 0600032c54 ("rust: drm: add DRM driver registration")
Cc: <stable@vger.kernel.org> # v6.16+
Link: https://patch.msgid.link/20260122221037.3462081-1-lyude@redhat.com
Convert all imports in the devres to use "kernel vertical" style.
Cc: Gary Guo <gary@garyguo.net>
Cc: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260121202212.4438-2-zhiw@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The Rust compiler cannot use dependencies built by other versions, e.g.:
error[E0514]: found crate `proc_macro2` compiled by an incompatible version of rustc
--> rust/quote/ext.rs:5:5
|
5 | use proc_macro2::{TokenStream, TokenTree};
| ^^^^^^^^^^^
|
= note: the following crate versions were found:
crate `proc_macro2` compiled by rustc 1.92.0 (ded5c06cf 2025-12-08): ./rust/libproc_macro2.rlib
= help: please recompile that crate using this compiler (rustc 1.93.0 (254b59607 2026-01-19)) (consider running `cargo clean` first)
Thus trigger a rebuild if the version text changes like we do in other
top-level cases (e.g. see commit aeb0e24abb ("kbuild: rust: replace
proc macros dependency on `core.o` with the version text")).
The build errors for now are hard to trigger, since we do not yet use
the new crates we just introduced (the use cases are coming in the next
merge window), but they can still be seen if e.g. one manually removes
one of the targets, so fix it already.
Fixes: 158a3b7211 ("rust: proc-macro2: enable support in kbuild")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260122054135.138445-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The Rust kernel code should be kept `rustdoc`-clean [1].
Our custom `srctree` link checker in the `rustdoc` target reports:
warning: srctree/ link to include/io-pgtable.h does not exist
Thus fix it.
Link: https://rust-for-linux.com/contributing#submit-checklist-addendum [1]
Fixes: 2e2f6b0ef8 ("rust: iommu: add io_pgtable abstraction")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The Rust kernel code should be kept `rustfmt`-clean [1].
Thus run the `rustfmt` target to fix the formatting issue.
Link: https://rust-for-linux.com/contributing#submit-checklist-addendum [1]
Fixes: 2e2f6b0ef8 ("rust: iommu: add io_pgtable abstraction")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Replace unsafe core::mem::zeroed() with pin_init::zeroed() for
blk_mq_tag_set initialization.
Signed-off-by: Ke Sun <sunke@kylinos.cn>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20260120083824.477339-4-sunke@kylinos.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace unsafe core::mem::zeroed() with pin_init::zeroed() for
queue_limits initialization.
Signed-off-by: Ke Sun <sunke@kylinos.cn>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20260120083824.477339-3-sunke@kylinos.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
HIPPI has not been relevant for over two decades. It was rapidly
eclipsed by Fibre Channel, and even when it was new, it was
confined to very high-end hardware. The HIPPI code has only
received tree-wide changes and fixes by inspection in the entire
Git history. Remove HIPPI support and the rrunner HIPPI driver,
and move the former maintainer to the CREDITS file. Keep the
include/uapi/linux/if_hippi.h header because it is used by the TUN
code, and to avoid breaking userspace, however unlikely that may be.
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Link: https://patch.msgid.link/20260119022451.22344-1-enelsonmoore@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Remove unnecessary temporary variables around to_result() calls and move
trailing semicolons outside unsafe blocks to improve readability and
produce cleaner rustfmt output.
No functional change intended.
Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Acked-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://patch.msgid.link/20260102-pwm-rust-v2-2-2702ce57d571@gmail.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
When initializing a PWM chip using pwmchip_alloc(), the allocated device
owns an initial reference that must be released on all error paths.
If __pinned_init() were to fail, the allocated pwm_chip would currently
leak because the error path returns without calling pwmchip_put().
Fixes: 7b3dce814a ("rust: pwm: Add Kconfig and basic data structures")
Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Acked-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://patch.msgid.link/20260102-pwm-rust-v2-1-2702ce57d571@gmail.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The `pwm::Registration::register` function provides no guarantee that the
function isn't called twice with the same pwm chip, which is considered
unsafe.
Add `pwm::UnregisteredChip` as wrapper around `pwm::Chip`.
Implement `pwm::UnregisteredChip::register` for the registration. This
function takes ownership of `pwm::UnregisteredChip` and therefore
guarantees that the registration can't be called twice on the same pwm
chip.
Signed-off-by: Markus Probst <markus.probst@posteo.de>
Tested-by: Michal Wilczynski <m.wilczynski@samsung.com>
Acked-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://patch.msgid.link/20251202-pwm_safe_register-v2-1-7a2e0d1e287f@posteo.de
[ukleinek: fixes a typo that Michal pointed out during review]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Update call sites in `pwm.rs` to import `ARef` and `AlwaysRefCounted`
from `sync::aref` instead of `types`.
This aligns with the ongoing effort to move `ARef` and
`AlwaysRefCounted` to sync.
Suggested-by: Benno Lossin <lossin@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1173
Signed-off-by: Shankari Anand <shankari.ak0208@gmail.com>
Acked-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://patch.msgid.link/20251123092438.182251-7-shankari.ak0208@gmail.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Switch the read_callback_file() documentation example from
core::sync::atomic::AtomicU32 to the kernel's Atomic because Rust
native atomics are not allowed to use in kernel.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251203000411.30434-1-fujita.tomonori@gmail.com
[ Use kernel vertical import style. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This will be used by the Tyr driver to create and modify the page table
of each address space on the GPU. Each time a mapping gets created or
removed by userspace, Tyr will call into GPUVM, which will figure out
which calls to map_pages and unmap_pages are required to map the data in
question in the page table so that the GPU may access those pages when
using that address space.
The Rust type wraps the struct using a raw pointer rather than the usual
Opaque+ARef approach because Opaque+ARef requires the target type to be
refcounted.
Signed-off-by: Asahi Lina <lina+kernel@asahilina.net>
Acked-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Tested-by: Deborah Brouwer <deborah.brouwer@collabora.com>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
[joro: Fixed up Rust import style]
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Refactors parts of the get() and find_best_match()
traversal logic to minimize the scope of unsafe blocks
and avoid duplicating same safety comments.
One of the removed comments was also misleading:
// SAFETY: `node` is a non-null node...
Ordering::Equal => return Some(unsafe { &(*this).value }),
as `node` should have been `this`.
No functional changes intended; this is purely a safety
improvement that reduces the amount of unsafe blocks
while keeping all invariants intact.
[ Alice writes:
"One consequence of creating a &_ to the bindings::rb_node struct means
that we assert immutability for the entire struct and not just the
rb_left/rb_right fields, but I have verified that this is ok."
- Miguel ]
Signed-off-by: Onur Özkan <work@onurozkan.dev>
Reviewed-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251113144547.502-1-work@onurozkan.dev
[ Reworded title and replaced `cursor_lower_bound()` with
`find_best_match()` in message. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
C-String literals were added in Rust 1.77. Replace instances of
`kernel::c_str!` with C-String literals where possible.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Igor Korotin <igor.korotin.linux@gmail.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Link: https://patch.msgid.link/20251222-cstr-i2c-v1-1-df1c258d4615@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Since `ALIGN` is a const parameter, this assertion can be done in const
context using the `assert!` macro.
Suggested-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251216-ptr_assert-v1-1-d8b2d5c5741d@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`build_assert` relies on the compiler to optimize out its error path,
lest build fails with the dreaded error:
ERROR: modpost: "rust_build_error" [path/to/module.ko] undefined!
It has been observed that very trivial code performing I/O accesses
(sometimes even using an immediate value) would seemingly randomly fail
with this error whenever `CLIPPY=1` was set. The same behavior was also
observed until different, very similar conditions [1][2].
The cause appears to be that the failing function is eventually using
`build_assert` with its argument, but is only annotated with
`#[inline]`. This gives the compiler freedom to not inline the function,
which it notably did when Clippy was active, triggering the error.
The fix is to annotate functions passing their argument to
`build_assert` with `#[inline(always)]`, telling the compiler to be as
aggressive as possible with their inlining. This is also the correct
behavior as inlining is mandatory for correct behavior in these cases.
Add a paragraph instructing to annotate such functions with
`#[inline(always)]` in `build_assert`'s documentation, and split its
example to illustrate.
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251208-io-build-assert-v3-1-98aded02c1ea@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This code is always inlined to avoid a build error if the error path of
`build_assert` cannot be optimized out. Add a comment justifying the
`#[inline(always)]` property to avoid it being taken away by mistake.
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251208-io-build-assert-v3-7-98aded02c1ea@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`build_assert` relies on the compiler to optimize out its error path.
Functions using it with its arguments must thus always be inlined,
otherwise the error path of `build_assert` might not be optimized out,
triggering a build error.
Cc: stable@vger.kernel.org
Fixes: bb38f35b35 ("rust: implement `kernel::sync::Refcount`")
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251208-io-build-assert-v3-5-98aded02c1ea@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`build_assert` relies on the compiler to optimize out its error path.
Functions using it with its arguments must thus always be inlined,
otherwise the error path of `build_assert` might not be optimized out,
triggering a build error.
Cc: stable@vger.kernel.org
Fixes: cc84ef3b88 ("rust: bits: add support for bits/genmask macros")
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251208-io-build-assert-v3-4-98aded02c1ea@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This feature allows users to use `&'static mut MaybeUninit<T>` as a
place to initialize the value. It mirrors an existing implemetation
for `Box<MaybeUninit>`, but enables users to use external allocation
mechanisms such as `static_cell` [1].
Signed-off-by: Oleksandr Babak <alexanderbabak@proton.me>
Link: https://crates.io/crates/static_cell [1]
[ Added link to `static_cell` - Benno ]
Signed-off-by: Benno Lossin <lossin@kernel.org>
The `Zeroable` type check uses a small dance with a raw pointer to aid
type inference. It turns out that this is not necessary and type
inference is powerful enough to resolve any ambiguity. Thus remove it.
Suggested-by: Gary Guo <gary@garyguo.net>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <lossin@kernel.org>
The initializer macro emits mutable references for already initialized
fields, which allows modifying or accessing them later in code blocks or
when initializing other fields. This behavior results in compiler errors
when combining with packed structs, since those do not permit creating
references to misaligned fields. For example:
#[repr(C, packed)]
struct Foo {
a: i8,
b: i32,
}
fn main() {
let _ = init!(Foo { a: -42, b: 42 });
}
This will lead to an error like this:
error[E0793]: reference to field of packed struct is unaligned
--> tests/ui/compile-fail/init/packed_struct.rs:10:13
|
10 | let _ = init!(Foo { a: -42, b: 42 });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: this struct is 1-byte aligned, but the type of this field may require higher alignment
= note: creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
= help: copy the field contents to a local variable, or replace the reference with a raw pointer and use `read_unaligned`/`write_unaligned` (loads and stores via `*p` must be properly aligned even when using raw pointers)
= note: this error originates in the macro `init` (in Nightly builds, run with -Z macro-backtrace for more info)
This was requested by Janne Grunau [1] and will most certainly be used
by the kernel when we eventually end up with trying to initialize packed
structs.
Thus add an initializer attribute `#[disable_initialized_field_access]`
that does what the name suggests: do not generate references to already
initialized fields.
There is space for future work: add yet another attribute which can be
applied on fields of initializers that ask for said field to be made
accessible. We can add that when the need arises.
Requested-by: Janne Grunau <j@jannau.net>
Link: https://lore.kernel.org/all/20251206170214.GE1097212@robin.jannau.net [1]
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <lossin@kernel.org>
Initializer fields ought to support the same attributes that are allowed
in struct initializers on fields. For example, `cfg` or lint levels such
as `expect`, `allow` etc. Add parsing support for these attributes using
syn to initializer fields and adjust the macro expansion accordingly.
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <lossin@kernel.org>
Initializer macros should use this attribute instead of manually parsing
the macro's input. This is because the syntax is now parsed using `syn`,
which permits more complex constructs to be parsed. In addition, this
ensures that the kernel's initializer marcos will have the exact same
syntax as the ones from pin-init.
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <lossin@kernel.org>
The `#[default_error(<type>)]` attribute can be used to supply a default
type as the error used for the `[pin_]init!` macros. This way one can
easily define custom `try_[pin_]init!` variants that default to your
project specific error type. Just write the following declarative macro:
macro_rules! try_init {
($($args:tt)*) => {
::pin_init::init!(
#[default_error(YourCustomErrorType)]
$($args)*
)
}
}
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <lossin@kernel.org>
Rewrite the initializer macros `[pin_]init!` using `syn`. No functional
changes intended aside from improved error messages on syntactic and
semantical errors. For example if one forgets to use `<-` with an
initializer (and instead uses `:`):
impl Bar {
fn new() -> impl PinInit<Self> { ... }
}
impl Foo {
fn new() -> impl PinInit<Self> {
pin_init!(Self { bar: Bar::new() })
}
}
Then the declarative macro would report:
error[E0308]: mismatched types
--> tests/ui/compile-fail/init/colon_instead_of_arrow.rs:21:9
|
14 | fn new() -> impl PinInit<Self> {
| ------------------ the found opaque type
...
21 | pin_init!(Self { bar: Bar::new() })
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| |
| expected `Bar`, found opaque type
| arguments to this function are incorrect
|
= note: expected struct `Bar`
found opaque type `impl pin_init::PinInit<Bar>`
note: function defined here
--> $RUST/core/src/ptr/mod.rs
|
| pub const unsafe fn write<T>(dst: *mut T, src: T) {
| ^^^^^
= note: this error originates in the macro `$crate::__init_internal` which comes from the expansion of the macro `pin_init` (in Nightly builds, run with -Z macro-backtrace for more info)
And the new error is:
error[E0308]: mismatched types
--> tests/ui/compile-fail/init/colon_instead_of_arrow.rs:21:31
|
14 | fn new() -> impl PinInit<Self> {
| ------------------ the found opaque type
...
21 | pin_init!(Self { bar: Bar::new() })
| --- ^^^^^^^^^^ expected `Bar`, found opaque type
| |
| arguments to this function are incorrect
|
= note: expected struct `Bar`
found opaque type `impl pin_init::PinInit<Bar>`
note: function defined here
--> $RUST/core/src/ptr/mod.rs
|
| pub const unsafe fn write<T>(dst: *mut T, src: T) {
| ^^^^^
Importantly, this error gives much more accurate span locations,
pointing to the offending field, rather than the entire macro
invocation.
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <lossin@kernel.org>
