The relative paths like the following are bothersome and don't work
with `O=` builds:
//! C headers: [`include/linux/phy.h`](../../../../../../../include/linux/phy.h).
This updates such links by using the `srctree`-relative link feature
introduced in 6.8-rc1 like:
//! C headers: [`include/linux/phy.h`](srctree/include/linux/phy.h).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in
Rust 1.75.0, which we were using in the PHYLIB abstractions.
The only unstable features allowed to be used outside the `kernel` crate
are still `new_uninit,offset_of`, though other code to be upstreamed
may increase the list.
Please see [4] for details.
# Other improvements
Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could
potentially use as an alternative for `ptr_metadata` in the future.
# Required changes
For this upgrade, no changes were required (i.e. on our side).
# `alloc` upgrade and reviewing
The vast majority of changes are due to our `alloc` fork being upgraded
at once.
There are two kinds of changes to be aware of: the ones coming from
upstream, which we should follow as closely as possible, and the updates
needed in our added fallible APIs to keep them matching the newer
infallible APIs coming from upstream.
Instead of taking a look at the diff of this patch, an alternative
approach is reviewing a diff of the changes between upstream `alloc` and
the kernel's. This allows to easily inspect the kernel additions only,
especially to check if the fallible methods we already have still match
the infallible ones in the new version coming from upstream.
Another approach is reviewing the changes introduced in the additions in
the kernel fork between the two versions. This is useful to spot
potentially unintended changes to our additions.
To apply these approaches, one may follow steps similar to the following
to generate a pair of patches that show the differences between upstream
Rust and the kernel (for the subset of `alloc` we use) before and after
applying this patch:
# Get the difference with respect to the old version.
git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
cut -d/ -f3- |
grep -Fv README.md |
xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
git -C linux diff --patch-with-stat --summary -R > old.patch
git -C linux restore rust/alloc
# Apply this patch.
git -C linux am rust-upgrade.patch
# Get the difference with respect to the new version.
git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
cut -d/ -f3- |
grep -Fv README.md |
xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
git -C linux diff --patch-with-stat --summary -R > new.patch
git -C linux restore rust/alloc
Now one may check the `new.patch` to take a look at the additions (first
approach) or at the difference between those two patches (second
approach). For the latter, a side-by-side tool is recommended.
Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/rust-lang/rust/issues/91850 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/issues/96283 [5]
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull Rust updates from Miguel Ojeda:
"Another routine one in terms of features. In terms of lines, this time
the 'alloc' version upgrade is less prominent, given that it was
fairly small (and we did not have two upgrades)
Toolchain and infrastructure:
- Upgrade to Rust 1.74.1
The patch release includes a fix for an ICE that the Apple AGX GPU
driver was hitting
- Support 'srctree'-relative links in Rust code documentation
- Automate part of the manual constants handling (i.e. the ones not
recognised by 'bindgen')
- Suppress searching builtin sysroot to avoid confusion with
installed sysroots, needed for the to-be-merged arm64 support which
uses a builtin target
- Ignore '__preserve_most' functions for 'bindgen'
- Reduce header inclusion bloat in exports
'kernel' crate:
- Implement 'Debug' for 'CString'
- Make 'CondVar::wait()' an uninterruptible wait
'macros' crate:
- Update 'paste!' to accept string literals
- Improve '#[vtable]' documentation
Documentation:
- Add testing section (KUnit and 'rusttest' target)
- Remove 'CC=clang' mentions
- Clarify that 'rustup override' applies to build directory"
* tag 'rust-6.8' of https://github.com/Rust-for-Linux/linux:
docs: rust: Clarify that 'rustup override' applies to build directory
docs: rust: Add rusttest info
docs: rust: remove `CC=clang` mentions
rust: support `srctree`-relative links
rust: sync: Makes `CondVar::wait()` an uninterruptible wait
rust: upgrade to Rust 1.74.1
rust: Suppress searching builtin sysroot
rust: macros: improve `#[vtable]` documentation
rust: macros: update 'paste!' macro to accept string literals
rust: bindings: rename const binding using sed
rust: Ignore preserve-most functions
rust: replace <linux/module.h> with <linux/export.h> in rust/exports.c
rust: kernel: str: Implement Debug for CString
This macro creates an array of kernel's `struct phy_driver` and
registers it. This also corresponds to the kernel's
`MODULE_DEVICE_TABLE` macro, which embeds the information for module
loading into the module binary file.
A PHY driver should use this macro.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds abstractions to implement network PHY drivers; the
driver registration and bindings for some of callback functions in
struct phy_driver and many genphy_ functions.
This feature is enabled with CONFIG_RUST_PHYLIB_ABSTRACTIONS=y.
This patch enables unstable const_maybe_uninit_zeroed feature for
kernel crate to enable unsafe code to handle a constant value with
uninitialized data. With the feature, the abstractions can initialize
a phy_driver structure with zero easily; instead of initializing all
the members by hand. It's supposed to be stable in the not so distant
future.
Link: https://github.com/rust-lang/rust/pull/116218
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Traits marked with `#[vtable]` need to provide default implementations
for optional functions. The C side represents these with `NULL` in the
vtable, so the default functions are never actually called. We do not
want to replicate the default behavior from C in Rust, because that is
not maintainable. Therefore we should use `build_error` in those default
implementations. The error message for that is provided at
`kernel::error::VTABLE_DEFAULT_ERROR`.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Finn Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20231026201855.1497680-1-benno.lossin@proton.me
[ Wrapped paragraph to 80 as requested and capitalized sentence. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Currently, for `const`s that bindgen doesn't recognise, we define a
helper constant with
const <TYPE> BINDINGS_<NAME> = <NAME>;
in `bindings_helper.h` and then we put
pub const <NAME>: <TYPE> = BINDINGS_<NAME>;
in `bindings/lib.rs`. This is fine since we currently only have 3
constants that are defined this way, but is going to be more annoying
when more constants are added since every new constant needs to be
defined in two places.
This patch changes the way we define constant helpers to
const <TYPE> RUST_CONST_HELPER_<NAME> = <NAME>;
and then use `sed` to postprocess Rust code generated by bindgen to
remove the distinct prefix, so users of the `bindings` crate can refer
to the name directly.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20231104145700.2495176-1-gary@garyguo.net
[ Reworded for typos. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull workqueue rust bindings from Tejun Heo:
"Add rust bindings to allow rust code to schedule work items on
workqueues.
While the current bindings don't cover all of the workqueue API, it
provides enough for basic usage and can be expanded as needed"
* tag 'wq-for-6.7-rust-bindings' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
rust: workqueue: add examples
rust: workqueue: add `try_spawn` helper method
rust: workqueue: implement `WorkItemPointer` for pointer types
rust: workqueue: add helper for defining work_struct fields
rust: workqueue: define built-in queues
rust: workqueue: add low-level workqueue bindings
rust: sync: add `Arc::{from_raw, into_raw}`
Pull rust updates from Miguel Ojeda:
"A small one compared to the previous one in terms of features. In
terms of lines, as usual, the 'alloc' version upgrade accounts for
most of them.
Toolchain and infrastructure:
- Upgrade to Rust 1.73.0
This time around, due to how the kernel and Rust schedules have
aligned, there are two upgrades in fact. They contain the fixes for
a few issues we reported to the Rust project.
In addition, a few cleanups indicated by the upgraded compiler or
possible thanks to it. For instance, the compiler now detects
redundant explicit links.
- A couple changes to the Rust 'Makefile' so that it can be used with
toybox tools, allowing Rust to be used in the Android kernel build.
x86:
- Enable IBT if enabled in C
Documentation:
- Add "The Rust experiment" section to the Rust index page
MAINTAINERS:
- Add Maintainer Entry Profile field ('P:').
- Update our 'W:' field to point to the webpage we have been building
this year"
* tag 'rust-6.7' of https://github.com/Rust-for-Linux/linux:
docs: rust: add "The Rust experiment" section
x86: Enable IBT in Rust if enabled in C
rust: Use grep -Ev rather than relying on GNU grep
rust: Use awk instead of recent xargs
rust: upgrade to Rust 1.73.0
rust: print: use explicit link in documentation
rust: task: remove redundant explicit link
rust: kernel: remove `#[allow(clippy::new_ret_no_self)]`
MAINTAINERS: add Maintainer Entry Profile field for Rust
MAINTAINERS: update Rust webpage
rust: upgrade to Rust 1.72.1
rust: arc: add explicit `drop()` around `Box::from_raw()`
The future `rustdoc` in the Rust 1.73.0 upgrade requires an explicit
link for `pr_info!`:
error: unresolved link to `pr_info`
--> rust/kernel/print.rs:395:63
|
395 | /// Use only when continuing a previous `pr_*!` macro (e.g. [`pr_info!`]).
| ^^^^^^^^ no item named `pr_info` in scope
|
= note: `macro_rules` named `pr_info` exists in this crate, but it is not in scope at this link's location
= note: `-D rustdoc::broken-intra-doc-links` implied by `-D warnings`
Thus do so to avoid a broken link while upgrading.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Finn Behrens <me@kloenk.dev>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://lore.kernel.org/r/20231005210556.466856-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Starting with Rust 1.73.0, `rustdoc` detects redundant explicit
links with its new lint `redundant_explicit_links` [1]:
error: redundant explicit link target
--> rust/kernel/task.rs:85:21
|
85 | /// [`current`](crate::current) macro because it is safe.
| --------- ^^^^^^^^^^^^^^ explicit target is redundant
| |
| because label contains path that resolves to same destination
|
= note: when a link's destination is not specified,
the label is used to resolve intra-doc links
= note: `-D rustdoc::redundant-explicit-links` implied by `-D warnings`
help: remove explicit link target
|
85 | /// [`current`] macro because it is safe.
In order to avoid the warning in the compiler upgrade commit,
make it an intra-doc link as the tool suggests.
Link: https://github.com/rust-lang/rust/pull/113167 [1]
Reviewed-by: Finn Behrens <me@kloenk.dev>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Link: https://lore.kernel.org/r/20231005210556.466856-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`Box::from_raw()` is `#[must_use]`, which means the result cannot
go unused.
In Rust 1.71.0, this was not detected because the block expression
swallows the diagnostic [1]:
unsafe { Box::from_raw(self.ptr.as_ptr()) };
It would have been detected, however, if the line had been instead:
unsafe { Box::from_raw(self.ptr.as_ptr()); }
i.e. the semicolon being inside the `unsafe` block, rather than
outside.
In Rust 1.72.0, the compiler started warning about this [2], so
without this patch we will get:
error: unused return value of `alloc::boxed::Box::<T>::from_raw` that must be used
--> rust/kernel/sync/arc.rs:302:22
|
302 | unsafe { Box::from_raw(self.ptr.as_ptr()) };
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: call `drop(Box::from_raw(ptr))` if you intend to drop the `Box`
= note: `-D unused-must-use` implied by `-D warnings`
help: use `let _ = ...` to ignore the resulting value
|
302 | unsafe { let _ = Box::from_raw(self.ptr.as_ptr()); };
| +++++++ +
Thus add an add an explicit `drop()` as the `#[must_use]`'s
annotation suggests (instead of the more general help line).
Link: https://github.com/rust-lang/rust/issues/104253 [1]
Link: https://github.com/rust-lang/rust/pull/112529 [2]
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Link: https://lore.kernel.org/r/20230823160244.188033-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This adds two examples of how to use the workqueue. The first example
shows how to use it when you only have one `work_struct` field, and the
second example shows how to use it when you have multiple `work_struct`
fields.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This adds a convenience method that lets you spawn a closure for
execution on a workqueue. This will be the most convenient way to use
workqueues, but it is fallible because it needs to allocate memory.
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This implements the `WorkItemPointer` trait for the pointer types that
you are likely to use the workqueue with. The `Arc` type is for
reference counted objects, and the `Pin<Box<T>>` type is for objects
where the caller has exclusive ownership of the object.
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The main challenge with defining `work_struct` fields is making sure
that the function pointer stored in the `work_struct` is appropriate for
the work item type it is embedded in. It needs to know the offset of the
`work_struct` field being used (even if there are several!) so that it
can do a `container_of`, and it needs to know the type of the work item
so that it can call into the right user-provided code. All of this needs
to happen in a way that provides a safe API to the user, so that users
of the workqueue cannot mix up the function pointers.
There are three important pieces that are relevant when doing this:
* The pointer type.
* The work item struct. This is what the pointer points at.
* The `work_struct` field. This is a field of the work item struct.
This patch introduces a separate trait for each piece. The pointer type
is given a `WorkItemPointer` trait, which pointer types need to
implement to be usable with the workqueue. This trait will be
implemented for `Arc` and `Box` in a later patch in this patchset.
Implementing this trait is unsafe because this is where the
`container_of` operation happens, but user-code will not need to
implement it themselves.
The work item struct should then implement the `WorkItem` trait. This
trait is where user-code specifies what they want to happen when a work
item is executed. It also specifies what the correct pointer type is.
Finally, to make the work item struct know the offset of its
`work_struct` field, we use a trait called `HasWork<T, ID>`. If a type
implements this trait, then the type declares that, at the given offset,
there is a field of type `Work<T, ID>`. The trait is marked unsafe
because the OFFSET constant must be correct, but we provide an
`impl_has_work!` macro that can safely implement `HasWork<T>` on a type.
The macro expands to something that only compiles if the specified field
really has the type `Work<T>`. It is used like this:
```
struct MyWorkItem {
work_field: Work<MyWorkItem, 1>,
}
impl_has_work! {
impl HasWork<MyWorkItem, 1> for MyWorkItem { self.work_field }
}
```
Note that since the `Work` type is annotated with an id, you can have
several `work_struct` fields by using a different id for each one.
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
We provide these methods because it lets us access these queues from
Rust without using unsafe code.
These methods return `&'static Queue`. References annotated with the
'static lifetime are used when the referent will stay alive forever.
That is ok for these queues because they are global variables and cannot
be destroyed.
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
FUJITA TomonoriandDavid S. Miller
Charalampos MitrodimasandMiguel Ojeda
Linus Torvalds
Boqun FengandMiguel Ojeda
Benno LossinandMiguel Ojeda
Gary GuoandMiguel Ojeda
Asahi LinaandMiguel Ojeda
Manmohan ShuklaandMiguel Ojeda
Wedson Almeida FilhoandMiguel Ojeda
Alice RyhlandTejun Heo