Add missing Markdown code span.
This was found using the Clippy `doc_markdown` lint, which we may want
to enable.
Fixes: dd09538fb4 ("rust: alloc: implement `Cmalloc` in module allocator_test")
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250324210359.1199574-5-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
For the Rust 1.87.0 release, Clippy was expected to warn with:
error: use `core::ptr::eq` when comparing raw pointers
--> rust/kernel/list.rs:438:12
|
438 | if self.first == item {
| ^^^^^^^^^^^^^^^^^^ help: try: `core::ptr::eq(self.first, item)`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_eq
= note: `-D clippy::ptr-eq` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::ptr_eq)]`
However, a backport to relax a bit the `clippy::ptr_eq` finally landed,
and thus Clippy did not warn by the time the release happened.
Thus remove the `allow`s added back then, which were added just in case
the backport did not land in time.
See commit a39f308709 ("rust: allow Rust 1.87.0's `clippy::ptr_eq`
lint") for details.
Link: https://github.com/rust-lang/rust/pull/140859 [1]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250520182125.806758-1-ojeda@kernel.org
[ Reworded for clarity. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Introduce Rust support for the `xarray` data structure:
- Add a rust abstraction for the `xarray` data structure. This abstraction
allows rust code to leverage the `xarray` to store types that implement
`ForeignOwnable`. This support is a dependency for memory backing feature of
the rust null block driver, which is waiting to be merged.
- Set up an entry in MAINTAINERS for the xarray rust support. Patches will go
to the new rust xarray tree and then via the rust subsystem tree for now.
`kernel` crate:
- Allow `ForeignOwnable` to carry information about the pointed-to type. This
helps asserting alignment requirements for the pointer passed to the foreign
language.
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Merge tag 'rust-xarray-for-v6.16' of https://github.com/Rust-for-Linux/linux into rust-next
Pull XArray updates from Andreas Hindborg:
"Introduce Rust support for the 'xarray' data structure:
- Add a Rust abstraction for the 'xarray' data structure. This
abstraction allows Rust code to leverage the 'xarray' to store
types that implement 'ForeignOwnable'. This support is a dependency
for memory backing feature of the Rust null block driver, which is
waiting to be merged.
- Set up an entry in MAINTAINERS for the XArray Rust support. Patches
will go to the new Rust XArray tree and then via the Rust subsystem
tree for now.
'kernel' crate:
- Allow 'ForeignOwnable' to carry information about the pointed-to
type. This helps asserting alignment requirements for the pointer
passed to the foreign language."
* tag 'rust-xarray-for-v6.16' of https://github.com/Rust-for-Linux/linux:
MAINTAINERS: add entry for Rust XArray API
rust: xarray: Add an abstraction for XArray
rust: types: add `ForeignOwnable::PointedTo`
Some comments in Rust files use raw URLs (http://example.com) rather
than Markdown autolinks <URL>. This inconsistency makes the
documentation less uniform and harder to maintain.
This patch converts all remaining raw URLs in Rust code comments to use
the Markdown autolink format, maintaining consistency with the rest of
the codebase which already uses this style.
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1153
Signed-off-by: Xizhe Yin <xizheyin@smail.nju.edu.cn>
Link: https://lore.kernel.org/r/509F0B66E3C1575D+20250407033441.5567-1-xizheyin@smail.nju.edu.cn
[ Used From form for Signed-off-by. Sorted tags. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This adds a variant of Vec::insert that does not allocate memory. This
makes it safe to use this function while holding a spinlock. Rust Binder
uses it for the range allocator fast path.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-7-06d20ad9366f@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This is needed by Rust Binder in the range allocator, and by upcoming
GPU drivers during firmware initialization.
Panics in the kernel are best avoided when possible, so an error is
returned if the index is out of bounds. An error type is used rather
than just returning Option<T> to let callers handle errors with ?.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-6-06d20ad9366f@google.com
[ Remove `# Panics` section; `Vec::remove() handles the error properly.`
- Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This adds a common Vec method called `retain` that removes all elements
that don't match a certain condition. Rust Binder uses it to find all
processes that match a given pid.
The stdlib retain method takes &T rather than &mut T and has a separate
retain_mut for the &mut T case. However, this is considered an API
mistake that can't be fixed now due to backwards compatibility. There's
no reason for us to repeat that mistake.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-5-06d20ad9366f@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This is like the stdlib method drain, except that it's hard-coded to use
the entire vector's range. Rust Binder uses it in the range allocator to
take ownership of everything in a vector in a case where reusing the
vector is desirable.
Implementing `DrainAll` in terms of `slice::IterMut` lets us reuse some
nice optimizations in core for the case where T is a ZST.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-4-06d20ad9366f@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This introduces a new method called `push_within_capacity` for appending
to a vector without attempting to allocate if the capacity is full. Rust
Binder will use this in various places to safely push to a vector while
holding a spinlock.
The implementation is moved to a push_within_capacity_unchecked method.
This is preferred over having push() call push_within_capacity()
followed by an unwrap_unchecked() for simpler unsafe.
Panics in the kernel are best avoided when possible, so an error is
returned if the vector does not have sufficient capacity. An error type
is used rather than just returning Result<(),T> to make it more
convenient for callers (i.e. they can use ? or unwrap).
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-3-06d20ad9366f@google.com
[ Remove public visibility from `Vec::push_within_capacity_unchecked()`.
- Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This introduces a basic method that our custom Vec is missing. I expect
that it will be used in many places, but at the time of writing, Rust
Binder has six calls to Vec::pop.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-2-06d20ad9366f@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Our custom Vec type is missing the stdlib method `clear`, thus add it.
It will be used in the miscdevice sample.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250502-vec-methods-v5-1-06d20ad9366f@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Toolchain and infrastructure:
- Extract the 'pin-init' API from the 'kernel' crate and make it into
a standalone crate.
In order to do this, the contents are rearranged so that they can
easily be kept in sync with the version maintained out-of-tree that
other projects have started to use too (or plan to, like QEMU).
This will reduce the maintenance burden for Benno, who will now have
his own sub-tree, and will simplify future expected changes like the
move to use 'syn' to simplify the implementation.
- Add '#[test]'-like support based on KUnit.
We already had doctests support based on KUnit, which takes the
examples in our Rust documentation and runs them under KUnit.
Now, we are adding the beginning of the support for "normal" tests,
similar to those the '#[test]' tests in userspace Rust. For instance:
#[kunit_tests(my_suite)]
mod tests {
#[test]
fn my_test() {
assert_eq!(1 + 1, 2);
}
}
Unlike with doctests, the 'assert*!'s do not map to the KUnit
assertion APIs yet.
- Check Rust signatures at compile time for functions called from C by
name.
In particular, introduce a new '#[export]' macro that can be placed
in the Rust function definition. It will ensure that the function
declaration on the C side matches the signature on the Rust function:
#[export]
pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize {
// ...
}
The macro essentially forces the compiler to compare the types of
the actual Rust function and the 'bindgen'-processed C signature.
These cases are rare so far. In the future, we may consider
introducing another tool, 'cbindgen', to generate C headers
automatically. Even then, having these functions explicitly marked
may be a good idea anyway.
- Enable the 'raw_ref_op' Rust feature: it is already stable, and
allows us to use the new '&raw' syntax, avoiding a couple macros.
After everyone has migrated, we will disallow the macros.
- Pass the correct target to 'bindgen' on Usermode Linux.
- Fix 'rusttest' build in macOS.
'kernel' crate:
- New 'hrtimer' module: add support for setting up intrusive timers
without allocating when starting the timer. Add support for
'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer types
for use with timer callbacks. Add support for setting clock source
and timer mode.
- New 'dma' module: add a simple DMA coherent allocator abstraction and
a test sample driver.
- 'list' module: make the linked list 'Cursor' point between elements,
rather than at an element, which is more convenient to us and allows
for cursors to empty lists; and document it with examples of how to
perform common operations with the provided methods.
- 'str' module: implement a few traits for 'BStr' as well as the
'strip_prefix()' method.
- 'sync' module: add 'Arc::as_ptr'.
- 'alloc' module: add 'Box::into_pin'.
- 'error' module: extend the 'Result' documentation, including a few
examples on different ways of handling errors, a warning about using
methods that may panic, and links to external documentation.
'macros' crate:
- 'module' macro: add the 'authors' key to support multiple authors.
The original key will be kept until everyone has migrated.
Documentation:
- Add error handling sections.
MAINTAINERS:
- Add Danilo Krummrich as reviewer of the Rust "subsystem".
- Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has
its own sub-tree.
- Add sub-tree for 'RUST [ALLOC]'.
- Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with Abdiel
Janulgue as primary maintainer. It will go through the sub-tree of
the 'RUST [ALLOC]' entry.
- Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as
maintainer. It has its own sub-tree.
And a few other cleanups and improvements.
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Merge tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Extract the 'pin-init' API from the 'kernel' crate and make it into
a standalone crate.
In order to do this, the contents are rearranged so that they can
easily be kept in sync with the version maintained out-of-tree that
other projects have started to use too (or plan to, like QEMU).
This will reduce the maintenance burden for Benno, who will now
have his own sub-tree, and will simplify future expected changes
like the move to use 'syn' to simplify the implementation.
- Add '#[test]'-like support based on KUnit.
We already had doctests support based on KUnit, which takes the
examples in our Rust documentation and runs them under KUnit.
Now, we are adding the beginning of the support for "normal" tests,
similar to those the '#[test]' tests in userspace Rust. For
instance:
#[kunit_tests(my_suite)]
mod tests {
#[test]
fn my_test() {
assert_eq!(1 + 1, 2);
}
}
Unlike with doctests, the 'assert*!'s do not map to the KUnit
assertion APIs yet.
- Check Rust signatures at compile time for functions called from C
by name.
In particular, introduce a new '#[export]' macro that can be placed
in the Rust function definition. It will ensure that the function
declaration on the C side matches the signature on the Rust
function:
#[export]
pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize {
// ...
}
The macro essentially forces the compiler to compare the types of
the actual Rust function and the 'bindgen'-processed C signature.
These cases are rare so far. In the future, we may consider
introducing another tool, 'cbindgen', to generate C headers
automatically. Even then, having these functions explicitly marked
may be a good idea anyway.
- Enable the 'raw_ref_op' Rust feature: it is already stable, and
allows us to use the new '&raw' syntax, avoiding a couple macros.
After everyone has migrated, we will disallow the macros.
- Pass the correct target to 'bindgen' on Usermode Linux.
- Fix 'rusttest' build in macOS.
'kernel' crate:
- New 'hrtimer' module: add support for setting up intrusive timers
without allocating when starting the timer. Add support for
'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer
types for use with timer callbacks. Add support for setting clock
source and timer mode.
- New 'dma' module: add a simple DMA coherent allocator abstraction
and a test sample driver.
- 'list' module: make the linked list 'Cursor' point between
elements, rather than at an element, which is more convenient to us
and allows for cursors to empty lists; and document it with
examples of how to perform common operations with the provided
methods.
- 'str' module: implement a few traits for 'BStr' as well as the
'strip_prefix()' method.
- 'sync' module: add 'Arc::as_ptr'.
- 'alloc' module: add 'Box::into_pin'.
- 'error' module: extend the 'Result' documentation, including a few
examples on different ways of handling errors, a warning about
using methods that may panic, and links to external documentation.
'macros' crate:
- 'module' macro: add the 'authors' key to support multiple authors.
The original key will be kept until everyone has migrated.
Documentation:
- Add error handling sections.
MAINTAINERS:
- Add Danilo Krummrich as reviewer of the Rust "subsystem".
- Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has
its own sub-tree.
- Add sub-tree for 'RUST [ALLOC]'.
- Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with
Abdiel Janulgue as primary maintainer. It will go through the
sub-tree of the 'RUST [ALLOC]' entry.
- Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as
maintainer. It has its own sub-tree.
And a few other cleanups and improvements"
* tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (71 commits)
rust: dma: add `Send` implementation for `CoherentAllocation`
rust: macros: fix `make rusttest` build on macOS
rust: block: refactor to use `&raw mut`
rust: enable `raw_ref_op` feature
rust: uaccess: name the correct function
rust: rbtree: fix comments referring to Box instead of KBox
rust: hrtimer: add maintainer entry
rust: hrtimer: add clocksource selection through `ClockId`
rust: hrtimer: add `HrTimerMode`
rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
rust: alloc: add `Box::into_pin`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
rust: hrtimer: add `UnsafeHrTimerPointer`
rust: hrtimer: allow timer restart from timer handler
rust: str: implement `strip_prefix` for `BStr`
rust: str: implement `AsRef<BStr>` for `[u8]` and `BStr`
rust: str: implement `Index` for `BStr`
rust: str: implement `PartialEq` for `BStr`
...
Introduce Rust support for the `hrtimer` subsystem:
- Add a way to use the `hrtimer` subsystem from Rust. Rust code can now set up
intrusive timers without allocating when starting the timer.
- Add support for `Pin<Box<_>>`, `Arc<_>`, `Pin<&_>` and `Pin<&mut _>` as
pointer types for use with timer callbacks.
- Add support for setting clock source and timer mode.
`kernel` crate:
- Add `Arc::as_ptr` for converting an `Arc` to a raw pointer. This is a
dependency for the `hrtimer` API.
- Add `Box::into_pin` for converting a `Box<_>` into a `Pin<Box<_>>` to align
with Rust `alloc`. This is a dependency for the `hrtimer` API.
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Merge tag 'rust-hrtimer-for-v6.15-v3' of https://github.com/Rust-for-Linux/linux into rust-next
Pull rust-hrtimer updates from Andreas Hindborg:
"Introduce Rust support for the 'hrtimer' subsystem:
- Add a way to use the 'hrtimer' subsystem from Rust. Rust code can
now set up intrusive timers without allocating when starting the
timer.
- Add support for 'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and
'Pin<&mut _>' as pointer types for use with timer callbacks.
- Add support for setting clock source and timer mode.
'kernel' crate:
- Add 'Arc::as_ptr' for converting an 'Arc' to a raw pointer. This is
a dependency for the 'hrtimer' API.
- Add 'Box::into_pin' for converting a 'Box<_>' into a 'Pin<Box<_>>'
to align with Rust 'alloc'. This is a dependency for the 'hrtimer'
API."
* tag 'rust-hrtimer-for-v6.15-v3' of https://github.com/Rust-for-Linux/linux:
rust: hrtimer: add maintainer entry
rust: hrtimer: add clocksource selection through `ClockId`
rust: hrtimer: add `HrTimerMode`
rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
rust: alloc: add `Box::into_pin`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
rust: hrtimer: add `UnsafeHrTimerPointer`
rust: hrtimer: allow timer restart from timer handler
rust: hrtimer: implement `HrTimerPointer` for `Arc`
rust: sync: add `Arc::as_ptr`
rust: hrtimer: introduce hrtimer support
Add an associated function to convert a `Box<T>` into a `Pin<Box<T>>`.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-9-73586e2bd5f1@kernel.org
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
Rename relative paths inside of the crate to still refer to the same
items, also rename paths inside of the kernel crate and adjust the build
system to build the crate.
[ Remove the `expect` (and thus the `lint_reasons` feature) since
the tree now uses `quote!` from `rust/macros/export.rs`. Remove the
`TokenStream` import removal, since it is now used as well.
In addition, temporarily (i.e. just for this commit) use an `--extern
force:alloc` to prevent an unknown `new_uninit` error in the `rustdoc`
target. For context, please see a similar case in:
https://lore.kernel.org/lkml/20240422090644.525520-1-ojeda@kernel.org/
And adjusted the message above. - Miguel ]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
When making pin-init its own crate, `Zeroable` will no longer be defined
by the kernel crate and thus implementing it for `Option<Box<T, A>>` is
no longer possible due to the orphan rule.
For this reason introduce a new `ZeroableOption` trait that circumvents
this problem.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-11-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In order to make pin-init a standalone crate, move kernel-specific code
directly into the kernel crate. Since `Opaque<T>` and `KBox<T>` are part
of the kernel, move their `Zeroable` implementation into the kernel
crate.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20250308110339.2997091-10-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In order to make pin-init a standalone crate, move kernel-specific code
directly into the kernel crate. This includes the `InPlaceInit<T>`
trait, its implementations and the implementations of `InPlaceWrite` for
`Arc` and `UniqueArc`. All of these use the kernel's error type which
will become unavailable in pin-init.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-9-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This function can be called with different function pointers when
different allocator (e.g. Kmalloc, Vmalloc, KVmalloc), however since
this function is not polymorphic, only one instance is generated,
and function pointers are used. Given that this function is called
for any Rust-side allocation/deallocation, performance matters a lot,
so making this function inlineable.
This is discovered when doing helper inlining work, since it's discovered
that even with helpers inlined, rust_helper_ symbols are still present
in final vmlinux binary, and it turns out this function is inhibiting
the inlining, and introducing indirect function calls.
Signed-off-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250105194054.545201-4-gary@garyguo.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
ISO C's `aligned_alloc` is partially implementation-defined; on some
systems it inherits stricter requirements from POSIX's `posix_memalign`.
This causes the call added in commit dd09538fb4 ("rust: alloc:
implement `Cmalloc` in module allocator_test") to fail on macOS because
it doesn't meet the requirements of `posix_memalign`.
Adjust the call to meet the POSIX requirement and add a comment. This
fixes failures in `make rusttest` on macOS.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Cc: stable@vger.kernel.org
Fixes: dd09538fb4 ("rust: alloc: implement `Cmalloc` in module allocator_test")
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20250213-aligned-alloc-v7-1-d2a2d0be164b@gmail.com
[ Added Cc: stable. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Previously, the `ForeignOwnable` trait had a method called `borrow_mut`
that was intended to provide mutable access to the inner value. However,
the method accidentally made it possible to change the address of the
object being modified, which usually isn't what we want. (And when we
want that, it can be done by calling `from_foreign` and `into_foreign`,
like how the old `borrow_mut` was implemented.)
In this patch, we introduce an alternate definition of `borrow_mut` that
solves the previous problem. Conceptually, given a pointer type `P` that
implements `ForeignOwnable`, the `borrow_mut` method gives you the same
kind of access as an `&mut P` would, except that it does not let you
change the pointer `P` itself.
This is analogous to how the existing `borrow` method provides the same
kind of access to the inner value as an `&P`.
Note that for types like `Arc`, having an `&mut Arc<T>` only gives you
immutable access to the inner `T`. This is because mutable references
assume exclusive access, but there might be other handles to the same
reference counted value, so the access isn't exclusive. The `Arc` type
implements this by making `borrow_mut` return the same type as `borrow`.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241120-borrow-mut-v6-6-80dbadd00951@gmail.com
[ Updated to `crate::ffi::`. Reworded title slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
It is slightly more convenient to operate on mut pointers, and this also
properly conveys the desired ownership semantics of the trait.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241120-borrow-mut-v6-4-80dbadd00951@gmail.com
[ Reworded title slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Replace `as` casts with `cast{,_mut}` calls which are a bit safer.
In one instance, remove an unnecessary `as` cast without replacement.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241120-borrow-mut-v6-2-80dbadd00951@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Add a rustdoc example and Kunit test to the `ArrayLayout` struct's
`ArrayLayout::new()` function.
This patch depends on the first patch in this series in order for the
KUnit test to compile.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://github.com/Rust-for-Linux/linux/issues/1131
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Jimmy Ostler <jtostler1@gmail.com>
Link: https://lore.kernel.org/r/f1564da5bcaa6be87aee312767a1d1694a03d1b7.1734674670.git.jtostler1@gmail.com
[ Added periods to example comments. Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Ensure consistency between `Debug` and `Display` for `Box` by
updating `Debug` to match the new `Display` style.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Guangbo Cui <2407018371@qq.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/tencent_1FC0BC283DA65DD81A8A14EEF25563934E05@qq.com
[ Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Currently `impl Display` is missing for `Box<T, A>`, as a result,
things like using `Box<..>` directly as an operand in `pr_info!()`
are impossible, which is less ergonomic compared to `Box` in Rust
std.
Therefore add `impl Display` for `Box`.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://github.com/Rust-for-Linux/linux/issues/1126
Signed-off-by: Guangbo Cui <2407018371@qq.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/tencent_2AD25C6A6898D3A598CBA54BB6AF59BB900A@qq.com
[ Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
We were accidentally allocating a layout for the *square* of the object
size due to a variable shadowing mishap.
Fixes memory bloat and page allocation failures in drm/asahi.
Reported-by: Janne Grunau <j@jannau.net>
Fixes: 9e7bbfa182 ("rust: alloc: introduce `ArrayLayout`")
Signed-off-by: Asahi Lina <lina@asahilina.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Link: https://lore.kernel.org/r/20241123-rust-fix-arraylayout-v1-1-197e64c95bd4@asahilina.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Currently FFI integer types are defined in libcore. This commit creates
the `ffi` crate and asks bindgen to use that crate for FFI integer types
instead of `core::ffi`.
This commit is preparatory and no type changes are made in this commit
yet.
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-4-gary@garyguo.net
[ Added `rustdoc`, `rusttest` and KUnit tests support. Rebased on top of
`rust-next` (e.g. migrated more `core::ffi` cases). Reworded crate
docs slightly and formatted. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Now that we have our own `Allocator`, `Box` and `Vec` types we can remove
Rust's `alloc` crate and the `new_uninit` unstable feature.
Also remove `Kmalloc`'s `GlobalAlloc` implementation -- we can't remove
this in a separate patch, since the `alloc` crate requires a
`#[global_allocator]` to set, that implements `GlobalAlloc`.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-29-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
So far the kernel's `Box` and `Vec` types can't be used by userspace
test cases, since all users of those types (e.g. `CString`) use kernel
allocators for instantiation.
In order to allow userspace test cases to make use of such types as
well, implement the `Cmalloc` allocator within the allocator_test module
and type alias all kernel allocators to `Cmalloc`. The `Cmalloc`
allocator uses libc's `realloc()` function as allocator backend.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-26-dakr@kernel.org
[ Removed the temporary `allow(dead_code)` as discussed in the list and
fixed typo, added backticks. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Now that all existing `Vec` users were moved to the kernel `Vec` type,
remove the `VecExt` extension.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-21-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Currently, we can't implement `FromIterator`. There are a couple of
issues with this trait in the kernel, namely:
- Rust's specialization feature is unstable. This prevents us to
optimize for the special case where `I::IntoIter` equals `Vec`'s
`IntoIter` type.
- We also can't use `I::IntoIter`'s type ID either to work around this,
since `FromIterator` doesn't require this type to be `'static`.
- `FromIterator::from_iter` does return `Self` instead of
`Result<Self, AllocError>`, hence we can't properly handle allocation
failures.
- Neither `Iterator::collect` nor `FromIterator::from_iter` can handle
additional allocation flags.
Instead, provide `IntoIter::collect`, such that we can at least convert
`IntoIter` into a `Vec` again.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-19-dakr@kernel.org
[ Added newline in documentation, changed case of section to be
consistent with an existing one, fixed typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Implement `IntoIterator` for `Vec`, `Vec`'s `IntoIter` type, as well as
`Iterator` for `IntoIter`.
`Vec::into_iter` disassembles the `Vec` into its raw parts; additionally,
`IntoIter` keeps track of a separate pointer, which is incremented
correspondingly as the iterator advances, while the length, or the count
of elements, is decremented.
This also means that `IntoIter` takes the ownership of the backing
buffer and is responsible to drop the remaining elements and free the
backing buffer, if it's dropped.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-18-dakr@kernel.org
[ Fixed typos. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`Vec` provides a contiguous growable array type with contents allocated
with the kernel's allocators (e.g. `Kmalloc`, `Vmalloc` or `KVmalloc`).
In contrast to Rust's stdlib `Vec` type, the kernel `Vec` type considers
the kernel's GFP flags for all appropriate functions, always reports
allocation failures through `Result<_, AllocError>` and remains
independent from unstable features.
[ This patch starts using a new unstable feature, `inline_const`, but
it was stabilized in Rust 1.79.0, i.e. the next version after the
minimum one, thus it will not be an issue. - Miguel ]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-17-dakr@kernel.org
[ Cleaned `rustdoc` unescaped backtick warning, added a couple more
backticks elsewhere, fixed typos, sorted `feature`s, rewrapped
documentation lines. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
When allocating memory for arrays using allocators, the `Layout::array`
function is typically used. It returns a result, since the given size
might be too big. However, `Vec` and its iterators store their allocated
capacity and thus they already did check that the size is not too big.
The `ArrayLayout` type provides this exact behavior, as it can be
infallibly converted into a `Layout`. Instead of a `usize` capacity,
`Vec` and other similar array-storing types can use `ArrayLayout`
instead.
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-16-dakr@kernel.org
[ Formatted a few comments. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Now that all existing `Box` users were moved to the kernel `Box` type,
remove the `BoxExt` extension and all other related extensions.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-14-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`Box` provides the simplest way to allocate memory for a generic type
with one of the kernel's allocators, e.g. `Kmalloc`, `Vmalloc` or
`KVmalloc`.
In contrast to Rust's `Box` type, the kernel `Box` type considers the
kernel's GFP flags for all appropriate functions, always reports
allocation failures through `Result<_, AllocError>` and remains
independent from unstable features.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-12-dakr@kernel.org
[ Added backticks, fixed typos. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Implement `Allocator` for `KVmalloc`, an `Allocator` that tries to
allocate memory with `kmalloc` first and, on failure, falls back to
`vmalloc`.
All memory allocations made with `KVmalloc` end up in
`kvrealloc_noprof()`; all frees in `kvfree()`.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-10-dakr@kernel.org
[ Reworded typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
