Merge tag 'rust-6.10' of https://github.com/Rust-for-Linux/linux

Pull Rust updates from Miguel Ojeda:
 "The most notable change is the drop of the 'alloc' in-tree fork. This
  is nicely reflected in the diffstat as a ~10k lines drop. In turn,
  this makes the version upgrades way simpler and smaller in the future,
  e.g. the latest one in commit 56f64b37 ("rust: upgrade to Rust
  1.78.0").

  More importantly, this increases the chances that a newer compiler
  version just works, which in turn means supporting several compiler
  versions is easier now. Thus we will look into finally setting a
  minimum version in the near future.

  Toolchain and infrastructure:

   - Upgrade to Rust 1.78.0

     This time around, due to how the kernel and Rust schedules have
     aligned, there are two upgrades in fact. These allow us to remove
     one more unstable feature ('offset_of') from the list, among other
     improvements

   - Drop 'alloc' in-tree fork of the standard library crate, which
     means all the unstable features used by 'alloc' (~30 language ones,
     ~60 library ones) are not a concern anymore

   - Support DWARFv5 via the '-Zdwarf-version' flag

   - Support zlib and zstd debuginfo compression via the
     '-Zdebuginfo-compression' flag

  'kernel' crate:

   - Support allocation flags ('GFP_*'), particularly in 'Box' (via
     'BoxExt'), 'Vec' (via 'VecExt'), 'Arc' and 'UniqueArc', as well as
     in the 'init' module APIs

   - Remove usage of the 'allocator_api' unstable feature

   - Remove 'try_' prefix in allocation APIs' names

   - Add 'VecExt' (an extension trait) to be able to drop the 'alloc'
     fork

   - Add the '{make,to}_{upper,lower}case()' methods to 'CStr'/'CString'

   - Add the 'as_ptr' method to 'ThisModule'

   - Add the 'from_raw' method to 'ArcBorrow'

   - Add the 'into_unique_or_drop' method to 'Arc'

   - Display column number in the 'dbg!' macro output by applying the
     equivalent change done to the standard library one

   - Migrate 'Work' to '#[pin_data]' thanks to the changes in the
     'macros' crate, which allows to remove an unsafe call in its 'new'
     associated function

   - Prevent namespacing issues when using the '[try_][pin_]init!'
     macros by changing the generated name of guard variables

   - Make the 'get' method in 'Opaque' const

   - Implement the 'Default' trait for 'LockClassKey'

   - Remove unneeded 'kernel::prelude' imports from doctests

   - Remove redundant imports

  'macros' crate:

   - Add 'decl_generics' to 'parse_generics()' to support default
     values, and use that to allow them in '#[pin_data]'

  Helpers:

   - Trivial English grammar fix

  Documentation:

   - Add section on Rust Kselftests to the 'Testing' document

   - Expand the 'Abstractions vs. bindings' section of the 'General
     Information' document"

* tag 'rust-6.10' of https://github.com/Rust-for-Linux/linux: (31 commits)
  rust: alloc: fix dangling pointer in VecExt<T>::reserve()
  rust: upgrade to Rust 1.78.0
  rust: kernel: remove redundant imports
  rust: sync: implement `Default` for `LockClassKey`
  docs: rust: extend abstraction and binding documentation
  docs: rust: Add instructions for the Rust kselftest
  rust: remove unneeded `kernel::prelude` imports from doctests
  rust: update `dbg!()` to format column number
  rust: helpers: Fix grammar in comment
  rust: init: change the generated name of guard variables
  rust: sync: add `Arc::into_unique_or_drop`
  rust: sync: add `ArcBorrow::from_raw`
  rust: types: Make Opaque::get const
  rust: kernel: remove usage of `allocator_api` unstable feature
  rust: init: update `init` module to take allocation flags
  rust: sync: update `Arc` and `UniqueArc` to take allocation flags
  rust: alloc: update `VecExt` to take allocation flags
  rust: alloc: introduce the `BoxExt` trait
  rust: alloc: introduce allocation flags
  rust: alloc: remove our fork of the `alloc` crate
  ...

Documentation/process/changes.rst

@@ -31,7 +31,7 @@ you probably needn't concern yourself with pcmciautils.
 ====================== ===============  ========================================
 GNU C                  5.1              gcc --version
 Clang/LLVM (optional)  13.0.1           clang --version
-Rust (optional)        1.76.0           rustc --version
+Rust (optional)        1.78.0           rustc --version
 bindgen (optional)     0.65.1           bindgen --version
 GNU make               3.82             make --version
 bash                   4.2              bash --version

Documentation/rust/general-information.rst

@@ -64,6 +64,63 @@ but it is intended that coverage is expanded as time goes on. "Leaf" modules
 (e.g. drivers) should not use the C bindings directly. Instead, subsystems
 should provide as-safe-as-possible abstractions as needed.
 
+.. code-block::
+
+	                                                rust/bindings/
+	                                               (rust/helpers.c)
+
+	                                                   include/ -----+ <-+
+	                                                                 |   |
+	  drivers/              rust/kernel/              +----------+ <-+   |
+	    fs/                                           | bindgen  |       |
+	   .../            +-------------------+          +----------+ --+   |
+	                   |    Abstractions   |                         |   |
+	+---------+        | +------+ +------+ |          +----------+   |   |
+	| my_foo  | -----> | | foo  | | bar  | | -------> | Bindings | <-+   |
+	| driver  |  Safe  | | sub- | | sub- | |  Unsafe  |          |       |
+	+---------+        | |system| |system| |          | bindings | <-----+
+	     |             | +------+ +------+ |          |  crate   |       |
+	     |             |   kernel crate    |          +----------+       |
+	     |             +-------------------+                             |
+	     |                                                               |
+	     +------------------# FORBIDDEN #--------------------------------+
+
+The main idea is to encapsulate all direct interaction with the kernel's C APIs
+into carefully reviewed and documented abstractions. Then users of these
+abstractions cannot introduce undefined behavior (UB) as long as:
+
+#. The abstractions are correct ("sound").
+#. Any ``unsafe`` blocks respect the safety contract necessary to call the
+   operations inside the block. Similarly, any ``unsafe impl``\ s respect the
+   safety contract necessary to implement the trait.
+
+Bindings
+~~~~~~~~
+
+By including a C header from ``include/`` into
+``rust/bindings/bindings_helper.h``, the ``bindgen`` tool will auto-generate the
+bindings for the included subsystem. After building, see the ``*_generated.rs``
+output files in the ``rust/bindings/`` directory.
+
+For parts of the C header that ``bindgen`` does not auto generate, e.g. C
+``inline`` functions or non-trivial macros, it is acceptable to add a small
+wrapper function to ``rust/helpers.c`` to make it available for the Rust side as
+well.
+
+Abstractions
+~~~~~~~~~~~~
+
+Abstractions are the layer between the bindings and the in-kernel users. They
+are located in ``rust/kernel/`` and their role is to encapsulate the unsafe
+access to the bindings into an as-safe-as-possible API that they expose to their
+users. Users of the abstractions include things like drivers or file systems
+written in Rust.
+
+Besides the safety aspect, the abstractions are supposed to be "ergonomic", in
+the sense that they turn the C interfaces into "idiomatic" Rust code. Basic
+examples are to turn the C resource acquisition and release into Rust
+constructors and destructors or C integer error codes into Rust's ``Result``\ s.
+
 
 Conditional compilation
 -----------------------

Documentation/rust/testing.rst

@@ -6,10 +6,11 @@ Testing
 This document contains useful information how to test the Rust code in the
 kernel.
 
-There are two sorts of tests:
+There are three sorts of tests:
 
 - The KUnit tests.
 - The ``#[test]`` tests.
+- The Kselftests.
 
 The KUnit tests
 ---------------
@@ -133,3 +134,25 @@ Additionally, there are the ``#[test]`` tests. These can be run using the
 This requires the kernel ``.config`` and downloads external repositories. It
 runs the ``#[test]`` tests on the host (currently) and thus is fairly limited in
 what these tests can test.
+
+The Kselftests
+--------------
+
+Kselftests are also available in the ``tools/testing/selftests/rust`` folder.
+
+The kernel config options required for the tests are listed in the
+``tools/testing/selftests/rust/config`` file and can be included with the aid
+of the ``merge_config.sh`` script::
+
+	./scripts/kconfig/merge_config.sh .config tools/testing/selftests/rust/config
+
+The kselftests are built within the kernel source tree and are intended to
+be executed on a system that is running the same kernel.
+
+Once a kernel matching the source tree has been installed and booted, the
+tests can be compiled and executed using the following command::
+
+	make TARGETS="rust" kselftest
+
+Refer to Documentation/dev-tools/kselftest.rst for the general Kselftest
+documentation.

rust/Makefile

@@ -61,15 +61,9 @@ core-cfgs = \
     --cfg no_fp_fmt_parse
 
 alloc-cfgs = \
-    --cfg no_borrow \
-    --cfg no_fmt \
     --cfg no_global_oom_handling \
-    --cfg no_macros \
     --cfg no_rc \
-    --cfg no_str \
-    --cfg no_string \
-    --cfg no_sync \
-    --cfg no_thin
+    --cfg no_sync
 
 quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $<
       cmd_rustdoc = \
@@ -123,7 +117,7 @@ rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE
 # due to things that are "configured out" vs. entirely non-existing ones.
 rustdoc-alloc: private rustc_target_flags = $(alloc-cfgs) \
     -Arustdoc::broken_intra_doc_links
-rustdoc-alloc: $(src)/alloc/lib.rs rustdoc-core rustdoc-compiler_builtins FORCE
+rustdoc-alloc: $(RUST_LIB_SRC)/alloc/src/lib.rs rustdoc-core rustdoc-compiler_builtins FORCE
 	+$(call if_changed,rustdoc)
 
 rustdoc-kernel: private rustc_target_flags = --extern alloc \
@@ -218,8 +212,6 @@ rusttest: rusttest-macros rusttest-kernel
 #   - `cargo` only considers the use case of building the standard library
 #     to use it in a given package. Thus we need to create a dummy package
 #     and pick the generated libraries from there.
-#   - Since we only keep a subset of upstream `alloc` in-tree, we need
-#     to recreate it on the fly by putting our sources on top.
 #   - The usual ways of modifying the dependency graph in `cargo` do not seem
 #     to apply for the `-Zbuild-std` steps, thus we have to mislead it
 #     by modifying the sources in the sysroot.
@@ -238,8 +230,6 @@ quiet_cmd_rustsysroot = RUSTSYSROOT
 	rm -rf $(objtree)/$(obj)/test; \
 	mkdir -p $(objtree)/$(obj)/test; \
 	cp -a $(rustc_sysroot) $(objtree)/$(obj)/test/sysroot; \
-	cp -r $(srctree)/$(src)/alloc/* \
-		$(objtree)/$(obj)/test/sysroot/lib/rustlib/src/rust/library/alloc/src; \
 	echo '\#!/bin/sh' > $(objtree)/$(obj)/test/rustc_sysroot; \
 	echo "$(RUSTC) --sysroot=$(abspath $(objtree)/$(obj)/test/sysroot) \"\$$@\"" \
 		>> $(objtree)/$(obj)/test/rustc_sysroot; \
@@ -447,7 +437,7 @@ $(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE
 $(obj)/alloc.o: private skip_clippy = 1
 $(obj)/alloc.o: private skip_flags = -Dunreachable_pub
 $(obj)/alloc.o: private rustc_target_flags = $(alloc-cfgs)
-$(obj)/alloc.o: $(src)/alloc/lib.rs $(obj)/compiler_builtins.o FORCE
+$(obj)/alloc.o: $(RUST_LIB_SRC)/alloc/src/lib.rs $(obj)/compiler_builtins.o FORCE
 	+$(call if_changed_dep,rustc_library)
 
 $(obj)/build_error.o: $(src)/build_error.rs $(obj)/compiler_builtins.o FORCE

rust/alloc/README.md

-# `alloc`
-
-These source files come from the Rust standard library, hosted in
-the <https://github.com/rust-lang/rust> repository, licensed under
-"Apache-2.0 OR MIT" and adapted for kernel use. For copyright details,
-see <https://github.com/rust-lang/rust/blob/master/COPYRIGHT>.
-
-Please note that these files should be kept as close as possible to
-upstream. In general, only additions should be performed (e.g. new
-methods). Eventually, changes should make it into upstream so that,
-at some point, this fork can be dropped from the kernel tree.
-
-The Rust upstream version on top of which these files are based matches
-the output of `scripts/min-tool-version.sh rustc`.
-
-
-## Rationale
-
-On one hand, kernel folks wanted to keep `alloc` in-tree to have more
-freedom in both workflow and actual features if actually needed
-(e.g. receiver types if we ended up using them), which is reasonable.
-
-On the other hand, Rust folks wanted to keep `alloc` as close as
-upstream as possible and avoid as much divergence as possible, which
-is also reasonable.
-
-We agreed on a middle-ground: we would keep a subset of `alloc`
-in-tree that would be as small and as close as possible to upstream.
-Then, upstream can start adding the functions that we add to `alloc`
-etc., until we reach a point where the kernel already knows exactly
-what it needs in `alloc` and all the new methods are merged into
-upstream, so that we can drop `alloc` from the kernel tree and go back
-to using the upstream one.
-
-By doing this, the kernel can go a bit faster now, and Rust can
-slowly incorporate and discuss the changes as needed.

rust/alloc/collections/mod.rs

-// SPDX-License-Identifier: Apache-2.0 OR MIT
-
-//! Collection types.
-
-#![stable(feature = "rust1", since = "1.0.0")]
-
-#[cfg(not(no_global_oom_handling))]
-pub mod binary_heap;
-#[cfg(not(no_global_oom_handling))]
-mod btree;
-#[cfg(not(no_global_oom_handling))]
-pub mod linked_list;
-#[cfg(not(no_global_oom_handling))]
-pub mod vec_deque;
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-pub mod btree_map {
-    //! An ordered map based on a B-Tree.
-    #[stable(feature = "rust1", since = "1.0.0")]
-    pub use super::btree::map::*;
-}
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-pub mod btree_set {
-    //! An ordered set based on a B-Tree.
-    #[stable(feature = "rust1", since = "1.0.0")]
-    pub use super::btree::set::*;
-}
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(no_inline)]
-pub use binary_heap::BinaryHeap;
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(no_inline)]
-pub use btree_map::BTreeMap;
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(no_inline)]
-pub use btree_set::BTreeSet;
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(no_inline)]
-pub use linked_list::LinkedList;
-
-#[cfg(not(no_global_oom_handling))]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(no_inline)]
-pub use vec_deque::VecDeque;
-
-use crate::alloc::{Layout, LayoutError};
-use core::fmt::Display;
-
-/// The error type for `try_reserve` methods.
-#[derive(Clone, PartialEq, Eq, Debug)]
-#[stable(feature = "try_reserve", since = "1.57.0")]
-pub struct TryReserveError {
-    kind: TryReserveErrorKind,
-}
-
-impl TryReserveError {
-    /// Details about the allocation that caused the error
-    #[inline]
-    #[must_use]
-    #[unstable(
-        feature = "try_reserve_kind",
-        reason = "Uncertain how much info should be exposed",
-        issue = "48043"
-    )]
-    pub fn kind(&self) -> TryReserveErrorKind {
-        self.kind.clone()
-    }
-}
-
-/// Details of the allocation that caused a `TryReserveError`
-#[derive(Clone, PartialEq, Eq, Debug)]
-#[unstable(
-    feature = "try_reserve_kind",
-    reason = "Uncertain how much info should be exposed",
-    issue = "48043"
-)]
-pub enum TryReserveErrorKind {
-    /// Error due to the computed capacity exceeding the collection's maximum
-    /// (usually `isize::MAX` bytes).
-    CapacityOverflow,
-
-    /// The memory allocator returned an error
-    AllocError {
-        /// The layout of allocation request that failed
-        layout: Layout,
-
-        #[doc(hidden)]
-        #[unstable(
-            feature = "container_error_extra",
-            issue = "none",
-            reason = "\
-            Enable exposing the allocator’s custom error value \
-            if an associated type is added in the future: \
-            https://github.com/rust-lang/wg-allocators/issues/23"
-        )]
-        non_exhaustive: (),
-    },
-}
-
-#[unstable(
-    feature = "try_reserve_kind",
-    reason = "Uncertain how much info should be exposed",
-    issue = "48043"
-)]
-impl From<TryReserveErrorKind> for TryReserveError {
-    #[inline]
-    fn from(kind: TryReserveErrorKind) -> Self {
-        Self { kind }
-    }
-}
-
-#[unstable(feature = "try_reserve_kind", reason = "new API", issue = "48043")]
-impl From<LayoutError> for TryReserveErrorKind {
-    /// Always evaluates to [`TryReserveErrorKind::CapacityOverflow`].
-    #[inline]
-    fn from(_: LayoutError) -> Self {
-        TryReserveErrorKind::CapacityOverflow
-    }
-}
-
-#[stable(feature = "try_reserve", since = "1.57.0")]
-impl Display for TryReserveError {
-    fn fmt(
-        &self,
-        fmt: &mut core::fmt::Formatter<'_>,
-    ) -> core::result::Result<(), core::fmt::Error> {
-        fmt.write_str("memory allocation failed")?;
-        let reason = match self.kind {
-            TryReserveErrorKind::CapacityOverflow => {
-                " because the computed capacity exceeded the collection's maximum"
-            }
-            TryReserveErrorKind::AllocError { .. } => {
-                " because the memory allocator returned an error"
-            }
-        };
-        fmt.write_str(reason)
-    }
-}
-
-/// An intermediate trait for specialization of `Extend`.
-#[doc(hidden)]
-#[cfg(not(no_global_oom_handling))]
-trait SpecExtend<I: IntoIterator> {
-    /// Extends `self` with the contents of the given iterator.
-    fn spec_extend(&mut self, iter: I);
-}
-
-#[stable(feature = "try_reserve", since = "1.57.0")]
-impl core::error::Error for TryReserveError {}

rust/alloc/lib.rs

-// SPDX-License-Identifier: Apache-2.0 OR MIT
-
-//! # The Rust core allocation and collections library
-//!
-//! This library provides smart pointers and collections for managing
-//! heap-allocated values.
-//!
-//! This library, like core, normally doesn’t need to be used directly
-//! since its contents are re-exported in the [`std` crate](../std/index.html).
-//! Crates that use the `#![no_std]` attribute however will typically
-//! not depend on `std`, so they’d use this crate instead.
-//!
-//! ## Boxed values
-//!
-//! The [`Box`] type is a smart pointer type. There can only be one owner of a
-//! [`Box`], and the owner can decide to mutate the contents, which live on the
-//! heap.
-//!
-//! This type can be sent among threads efficiently as the size of a `Box` value
-//! is the same as that of a pointer. Tree-like data structures are often built
-//! with boxes because each node often has only one owner, the parent.
-//!
-//! ## Reference counted pointers
-//!
-//! The [`Rc`] type is a non-threadsafe reference-counted pointer type intended
-//! for sharing memory within a thread. An [`Rc`] pointer wraps a type, `T`, and
-//! only allows access to `&T`, a shared reference.
-//!
-//! This type is useful when inherited mutability (such as using [`Box`]) is too
-//! constraining for an application, and is often paired with the [`Cell`] or
-//! [`RefCell`] types in order to allow mutation.
-//!
-//! ## Atomically reference counted pointers
-//!
-//! The [`Arc`] type is the threadsafe equivalent of the [`Rc`] type. It
-//! provides all the same functionality of [`Rc`], except it requires that the
-//! contained type `T` is shareable. Additionally, [`Arc<T>`][`Arc`] is itself
-//! sendable while [`Rc<T>`][`Rc`] is not.
-//!
-//! This type allows for shared access to the contained data, and is often
-//! paired with synchronization primitives such as mutexes to allow mutation of
-//! shared resources.
-//!
-//! ## Collections
-//!
-//! Implementations of the most common general purpose data structures are
-//! defined in this library. They are re-exported through the
-//! [standard collections library](../std/collections/index.html).
-//!
-//! ## Heap interfaces
-//!
-//! The [`alloc`](alloc/index.html) module defines the low-level interface to the
-//! default global allocator. It is not compatible with the libc allocator API.
-//!
-//! [`Arc`]: sync
-//! [`Box`]: boxed
-//! [`Cell`]: core::cell
-//! [`Rc`]: rc
-//! [`RefCell`]: core::cell
-
-// To run alloc tests without x.py without ending up with two copies of alloc, Miri needs to be
-// able to "empty" this crate. See <https://github.com/rust-lang/miri-test-libstd/issues/4>.
-// rustc itself never sets the feature, so this line has no effect there.
-#![cfg(any(not(feature = "miri-test-libstd"), test, doctest))]
-//
-#![allow(unused_attributes)]
-#![stable(feature = "alloc", since = "1.36.0")]
-#![doc(
-    html_playground_url = "https://play.rust-lang.org/",
-    issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
-    test(no_crate_inject, attr(allow(unused_variables), deny(warnings)))
-)]
-#![doc(cfg_hide(
-    not(test),
-    not(any(test, bootstrap)),
-    any(not(feature = "miri-test-libstd"), test, doctest),
-    no_global_oom_handling,
-    not(no_global_oom_handling),
-    not(no_rc),
-    not(no_sync),
-    target_has_atomic = "ptr"
-))]
-#![doc(rust_logo)]
-#![feature(rustdoc_internals)]
-#![no_std]
-#![needs_allocator]
-// Lints:
-#![deny(unsafe_op_in_unsafe_fn)]
-#![deny(fuzzy_provenance_casts)]
-#![warn(deprecated_in_future)]
-#![warn(missing_debug_implementations)]
-#![warn(missing_docs)]
-#![allow(explicit_outlives_requirements)]
-#![warn(multiple_supertrait_upcastable)]
-#![allow(internal_features)]
-#![allow(rustdoc::redundant_explicit_links)]
-//
-// Library features:
-// tidy-alphabetical-start
-#![cfg_attr(not(no_global_oom_handling), feature(const_alloc_error))]
-#![cfg_attr(not(no_global_oom_handling), feature(const_btree_len))]
-#![cfg_attr(test, feature(is_sorted))]
-#![cfg_attr(test, feature(new_uninit))]
-#![feature(alloc_layout_extra)]
-#![feature(allocator_api)]
-#![feature(array_chunks)]
-#![feature(array_into_iter_constructors)]
-#![feature(array_methods)]
-#![feature(array_windows)]
-#![feature(ascii_char)]
-#![feature(assert_matches)]
-#![feature(async_iterator)]
-#![feature(coerce_unsized)]
-#![feature(const_align_of_val)]
-#![feature(const_box)]
-#![cfg_attr(not(no_borrow), feature(const_cow_is_borrowed))]
-#![feature(const_eval_select)]
-#![feature(const_maybe_uninit_as_mut_ptr)]
-#![feature(const_maybe_uninit_write)]
-#![feature(const_pin)]
-#![feature(const_refs_to_cell)]
-#![feature(const_size_of_val)]
-#![feature(const_waker)]
-#![feature(core_intrinsics)]
-#![feature(core_panic)]
-#![feature(deprecated_suggestion)]
-#![feature(dispatch_from_dyn)]
-#![feature(error_generic_member_access)]
-#![feature(error_in_core)]
-#![feature(exact_size_is_empty)]
-#![feature(extend_one)]
-#![feature(fmt_internals)]
-#![feature(fn_traits)]
-#![feature(hasher_prefixfree_extras)]
-#![feature(inline_const)]
-#![feature(inplace_iteration)]
-#![feature(iter_advance_by)]
-#![feature(iter_next_chunk)]
-#![feature(iter_repeat_n)]
-#![feature(layout_for_ptr)]
-#![feature(maybe_uninit_slice)]
-#![feature(maybe_uninit_uninit_array)]
-#![feature(maybe_uninit_uninit_array_transpose)]
-#![feature(pattern)]
-#![feature(ptr_internals)]
-#![feature(ptr_metadata)]
-#![feature(ptr_sub_ptr)]
-#![feature(receiver_trait)]
-#![feature(set_ptr_value)]
-#![feature(sized_type_properties)]
-#![feature(slice_from_ptr_range)]
-#![feature(slice_group_by)]
-#![feature(slice_ptr_get)]
-#![feature(slice_ptr_len)]
-#![feature(slice_range)]
-#![feature(std_internals)]
-#![feature(str_internals)]
-#![feature(strict_provenance)]
-#![feature(trusted_fused)]
-#![feature(trusted_len)]
-#![feature(trusted_random_access)]
-#![feature(try_trait_v2)]
-#![feature(tuple_trait)]
-#![feature(unchecked_math)]
-#![feature(unicode_internals)]
-#![feature(unsize)]
-#![feature(utf8_chunks)]
-// tidy-alphabetical-end
-//
-// Language features:
-// tidy-alphabetical-start
-#![cfg_attr(not(test), feature(coroutine_trait))]
-#![cfg_attr(test, feature(panic_update_hook))]
-#![cfg_attr(test, feature(test))]
-#![feature(allocator_internals)]
-#![feature(allow_internal_unstable)]
-#![feature(associated_type_bounds)]
-#![feature(c_unwind)]
-#![feature(cfg_sanitize)]
-#![feature(const_mut_refs)]
-#![feature(const_precise_live_drops)]
-#![feature(const_ptr_write)]
-#![feature(const_trait_impl)]
-#![feature(const_try)]
-#![feature(dropck_eyepatch)]
-#![feature(exclusive_range_pattern)]
-#![feature(fundamental)]
-#![feature(hashmap_internals)]
-#![feature(lang_items)]
-#![feature(min_specialization)]
-#![feature(multiple_supertrait_upcastable)]
-#![feature(negative_impls)]
-#![feature(never_type)]
-#![feature(pointer_is_aligned)]
-#![feature(rustc_allow_const_fn_unstable)]
-#![feature(rustc_attrs)]
-#![feature(slice_internals)]
-#![feature(staged_api)]
-#![feature(stmt_expr_attributes)]
-#![feature(unboxed_closures)]
-#![feature(unsized_fn_params)]
-#![feature(with_negative_coherence)]
-// tidy-alphabetical-end
-//
-// Rustdoc features:
-#![feature(doc_cfg)]
-#![feature(doc_cfg_hide)]
-// Technically, this is a bug in rustdoc: rustdoc sees the documentation on `#[lang = slice_alloc]`
-// blocks is for `&[T]`, which also has documentation using this feature in `core`, and gets mad
-// that the feature-gate isn't enabled. Ideally, it wouldn't check for the feature gate for docs
-// from other crates, but since this can only appear for lang items, it doesn't seem worth fixing.
-#![feature(intra_doc_pointers)]
-
-// Allow testing this library
-#[cfg(test)]
-#[macro_use]
-extern crate std;
-#[cfg(test)]
-extern crate test;
-#[cfg(test)]
-mod testing;
-
-// Module with internal macros used by other modules (needs to be included before other modules).
-#[cfg(not(no_macros))]
-#[macro_use]
-mod macros;
-
-mod raw_vec;
-
-// Heaps provided for low-level allocation strategies
-
-pub mod alloc;
-
-// Primitive types using the heaps above
-
-// Need to conditionally define the mod from `boxed.rs` to avoid
-// duplicating the lang-items when building in test cfg; but also need
-// to allow code to have `use boxed::Box;` declarations.
-#[cfg(not(test))]
-pub mod boxed;
-#[cfg(test)]
-mod boxed {
-    pub use std::boxed::Box;
-}
-#[cfg(not(no_borrow))]
-pub mod borrow;
-pub mod collections;
-#[cfg(all(not(no_rc), not(no_sync), not(no_global_oom_handling)))]
-pub mod ffi;
-#[cfg(not(no_fmt))]
-pub mod fmt;
-#[cfg(not(no_rc))]
-pub mod rc;
-pub mod slice;
-#[cfg(not(no_str))]
-pub mod str;
-#[cfg(not(no_string))]
-pub mod string;
-#[cfg(all(not(no_rc), not(no_sync), target_has_atomic = "ptr"))]
-pub mod sync;
-#[cfg(all(not(no_global_oom_handling), not(no_rc), not(no_sync), target_has_atomic = "ptr"))]
-pub mod task;
-#[cfg(test)]
-mod tests;
-pub mod vec;
-
-#[doc(hidden)]
-#[unstable(feature = "liballoc_internals", issue = "none", reason = "implementation detail")]
-pub mod __export {
-    pub use core::format_args;
-}
-
-#[cfg(test)]
-#[allow(dead_code)] // Not used in all configurations
-pub(crate) mod test_helpers {
-    /// Copied from `std::test_helpers::test_rng`, since these tests rely on the
-    /// seed not being the same for every RNG invocation too.
-    pub(crate) fn test_rng() -> rand_xorshift::XorShiftRng {
-        use std::hash::{BuildHasher, Hash, Hasher};
-        let mut hasher = std::hash::RandomState::new().build_hasher();
-        std::panic::Location::caller().hash(&mut hasher);
-        let hc64 = hasher.finish();
-        let seed_vec =
-            hc64.to_le_bytes().into_iter().chain(0u8..8).collect::<crate::vec::Vec<u8>>();
-        let seed: [u8; 16] = seed_vec.as_slice().try_into().unwrap();
-        rand::SeedableRng::from_seed(seed)
-    }
-}

rust/alloc/vec/drain.rs

-// SPDX-License-Identifier: Apache-2.0 OR MIT
-
-use crate::alloc::{Allocator, Global};
-use core::fmt;
-use core::iter::{FusedIterator, TrustedLen};
-use core::mem::{self, ManuallyDrop, SizedTypeProperties};
-use core::ptr::{self, NonNull};
-use core::slice::{self};
-
-use super::Vec;
-
-/// A draining iterator for `Vec<T>`.
-///
-/// This `struct` is created by [`Vec::drain`].
-/// See its documentation for more.
-///
-/// # Example
-///
-/// ```
-/// let mut v = vec![0, 1, 2];
-/// let iter: std::vec::Drain<'_, _> = v.drain(..);
-/// ```
-#[stable(feature = "drain", since = "1.6.0")]
-pub struct Drain<
-    'a,
-    T: 'a,
-    #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator + 'a = Global,
-> {
-    /// Index of tail to preserve
-    pub(super) tail_start: usize,
-    /// Length of tail
-    pub(super) tail_len: usize,
-    /// Current remaining range to remove
-    pub(super) iter: slice::Iter<'a, T>,
-    pub(super) vec: NonNull<Vec<T, A>>,
-}
-
-#[stable(feature = "collection_debug", since = "1.17.0")]
-impl<T: fmt::Debug, A: Allocator> fmt::Debug for Drain<'_, T, A> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_tuple("Drain").field(&self.iter.as_slice()).finish()
-    }
-}
-
-impl<'a, T, A: Allocator> Drain<'a, T, A> {
-    /// Returns the remaining items of this iterator as a slice.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// let mut vec = vec!['a', 'b', 'c'];
-    /// let mut drain = vec.drain(..);
-    /// assert_eq!(drain.as_slice(), &['a', 'b', 'c']);
-    /// let _ = drain.next().unwrap();
-    /// assert_eq!(drain.as_slice(), &['b', 'c']);
-    /// ```
-    #[must_use]
-    #[stable(feature = "vec_drain_as_slice", since = "1.46.0")]
-    pub fn as_slice(&self) -> &[T] {
-        self.iter.as_slice()
-    }
-
-    /// Returns a reference to the underlying allocator.
-    #[unstable(feature = "allocator_api", issue = "32838")]
-    #[must_use]
-    #[inline]
-    pub fn allocator(&self) -> &A {
-        unsafe { self.vec.as_ref().allocator() }
-    }
-
-    /// Keep unyielded elements in the source `Vec`.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(drain_keep_rest)]
-    ///
-    /// let mut vec = vec!['a', 'b', 'c'];
-    /// let mut drain = vec.drain(..);
-    ///
-    /// assert_eq!(drain.next().unwrap(), 'a');
-    ///
-    /// // This call keeps 'b' and 'c' in the vec.
-    /// drain.keep_rest();
-    ///
-    /// // If we wouldn't call `keep_rest()`,
-    /// // `vec` would be empty.
-    /// assert_eq!(vec, ['b', 'c']);
-    /// ```
-    #[unstable(feature = "drain_keep_rest", issue = "101122")]
-    pub fn keep_rest(self) {
-        // At this moment layout looks like this:
-        //
-        // [head] [yielded by next] [unyielded] [yielded by next_back] [tail]
-        //        ^-- start         \_________/-- unyielded_len        \____/-- self.tail_len
-        //                          ^-- unyielded_ptr                  ^-- tail
-        //
-        // Normally `Drop` impl would drop [unyielded] and then move [tail] to the `start`.
-        // Here we want to
-        // 1. Move [unyielded] to `start`
-        // 2. Move [tail] to a new start at `start + len(unyielded)`
-        // 3. Update length of the original vec to `len(head) + len(unyielded) + len(tail)`
-        //    a. In case of ZST, this is the only thing we want to do
-        // 4. Do *not* drop self, as everything is put in a consistent state already, there is nothing to do
-        let mut this = ManuallyDrop::new(self);
-
-        unsafe {
-            let source_vec = this.vec.as_mut();
-
-            let start = source_vec.len();
-            let tail = this.tail_start;
-
-            let unyielded_len = this.iter.len();
-            let unyielded_ptr = this.iter.as_slice().as_ptr();
-
-            // ZSTs have no identity, so we don't need to move them around.
-            if !T::IS_ZST {
-                let start_ptr = source_vec.as_mut_ptr().add(start);
-
-                // memmove back unyielded elements
-                if unyielded_ptr != start_ptr {
-                    let src = unyielded_ptr;
-                    let dst = start_ptr;
-
-                    ptr::copy(src, dst, unyielded_len);
-                }
-
-                // memmove back untouched tail
-                if tail != (start + unyielded_len) {
-                    let src = source_vec.as_ptr().add(tail);
-                    let dst = start_ptr.add(unyielded_len);
-                    ptr::copy(src, dst, this.tail_len);
-                }
-            }
-
-            source_vec.set_len(start + unyielded_len + this.tail_len);
-        }
-    }
-}
-
-#[stable(feature = "vec_drain_as_slice", since = "1.46.0")]
-impl<'a, T, A: Allocator> AsRef<[T]> for Drain<'a, T, A> {
-    fn as_ref(&self) -> &[T] {
-        self.as_slice()
-    }
-}
-
-#[stable(feature = "drain", since = "1.6.0")]
-unsafe impl<T: Sync, A: Sync + Allocator> Sync for Drain<'_, T, A> {}
-#[stable(feature = "drain", since = "1.6.0")]
-unsafe impl<T: Send, A: Send + Allocator> Send for Drain<'_, T, A> {}
-
-#[stable(feature = "drain", since = "1.6.0")]
-impl<T, A: Allocator> Iterator for Drain<'_, T, A> {
-    type Item = T;
-
-    #[inline]
-    fn next(&mut self) -> Option<T> {
-        self.iter.next().map(|elt| unsafe { ptr::read(elt as *const _) })
-    }
-
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        self.iter.size_hint()
-    }
-}
-
-#[stable(feature = "drain", since = "1.6.0")]
-impl<T, A: Allocator> DoubleEndedIterator for Drain<'_, T, A> {
-    #[inline]
-    fn next_back(&mut self) -> Option<T> {
-        self.iter.next_back().map(|elt| unsafe { ptr::read(elt as *const _) })
-    }
-}
-
-#[stable(feature = "drain", since = "1.6.0")]
-impl<T, A: Allocator> Drop for Drain<'_, T, A> {
-    fn drop(&mut self) {
-        /// Moves back the un-`Drain`ed elements to restore the original `Vec`.
-        struct DropGuard<'r, 'a, T, A: Allocator>(&'r mut Drain<'a, T, A>);
-
-        impl<'r, 'a, T, A: Allocator> Drop for DropGuard<'r, 'a, T, A> {
-            fn drop(&mut self) {
-                if self.0.tail_len > 0 {
-                    unsafe {
-                        let source_vec = self.0.vec.as_mut();
-                        // memmove back untouched tail, update to new length
-                        let start = source_vec.len();
-                        let tail = self.0.tail_start;
-                        if tail != start {
-                            let src = source_vec.as_ptr().add(tail);
-                            let dst = source_vec.as_mut_ptr().add(start);
-                            ptr::copy(src, dst, self.0.tail_len);
-                        }
-                        source_vec.set_len(start + self.0.tail_len);
-                    }
-                }
-            }
-        }
-
-        let iter = mem::take(&mut self.iter);
-        let drop_len = iter.len();
-
-        let mut vec = self.vec;
-
-        if T::IS_ZST {
-            // ZSTs have no identity, so we don't need to move them around, we only need to drop the correct amount.
-            // this can be achieved by manipulating the Vec length instead of moving values out from `iter`.
-            unsafe {
-                let vec = vec.as_mut();
-                let old_len = vec.len();
-                vec.set_len(old_len + drop_len + self.tail_len);
-                vec.truncate(old_len + self.tail_len);
-            }
-
-            return;
-        }
-
-        // ensure elements are moved back into their appropriate places, even when drop_in_place panics
-        let _guard = DropGuard(self);
-
-        if drop_len == 0 {
-            return;
-        }
-
-        // as_slice() must only be called when iter.len() is > 0 because
-        // it also gets touched by vec::Splice which may turn it into a dangling pointer
-        // which would make it and the vec pointer point to different allocations which would
-        // lead to invalid pointer arithmetic below.
-        let drop_ptr = iter.as_slice().as_ptr();
-
-        unsafe {
-            // drop_ptr comes from a slice::Iter which only gives us a &[T] but for drop_in_place
-            // a pointer with mutable provenance is necessary. Therefore we must reconstruct
-            // it from the original vec but also avoid creating a &mut to the front since that could
-            // invalidate raw pointers to it which some unsafe code might rely on.
-            let vec_ptr = vec.as_mut().as_mut_ptr();
-            let drop_offset = drop_ptr.sub_ptr(vec_ptr);
-            let to_drop = ptr::slice_from_raw_parts_mut(vec_ptr.add(drop_offset), drop_len);
-            ptr::drop_in_place(to_drop);
-        }
-    }
-}
-
-#[stable(feature = "drain", since = "1.6.0")]
-impl<T, A: Allocator> ExactSizeIterator for Drain<'_, T, A> {
-    fn is_empty(&self) -> bool {
-        self.iter.is_empty()
-    }
-}
-
-#[unstable(feature = "trusted_len", issue = "37572")]
-unsafe impl<T, A: Allocator> TrustedLen for Drain<'_, T, A> {}
-
-#[stable(feature = "fused", since = "1.26.0")]
-impl<T, A: Allocator> FusedIterator for Drain<'_, T, A> {}

rust/alloc/vec/extract_if.rs

-// SPDX-License-Identifier: Apache-2.0 OR MIT
-
-use crate::alloc::{Allocator, Global};
-use core::ptr;
-use core::slice;
-
-use super::Vec;
-
-/// An iterator which uses a closure to determine if an element should be removed.
-///
-/// This struct is created by [`Vec::extract_if`].
-/// See its documentation for more.
-///
-/// # Example
-///
-/// ```
-/// #![feature(extract_if)]
-///
-/// let mut v = vec![0, 1, 2];
-/// let iter: std::vec::ExtractIf<'_, _, _> = v.extract_if(|x| *x % 2 == 0);
-/// ```
-#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")]
-#[derive(Debug)]
-#[must_use = "iterators are lazy and do nothing unless consumed"]
-pub struct ExtractIf<
-    'a,
-    T,
-    F,
-    #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global,
-> where
-    F: FnMut(&mut T) -> bool,
-{
-    pub(super) vec: &'a mut Vec<T, A>,
-    /// The index of the item that will be inspected by the next call to `next`.
-    pub(super) idx: usize,
-    /// The number of items that have been drained (removed) thus far.
-    pub(super) del: usize,
-    /// The original length of `vec` prior to draining.
-    pub(super) old_len: usize,
-    /// The filter test predicate.
-    pub(super) pred: F,
-}
-
-impl<T, F, A: Allocator> ExtractIf<'_, T, F, A>
-where
-    F: FnMut(&mut T) -> bool,
-{
-    /// Returns a reference to the underlying allocator.
-    #[unstable(feature = "allocator_api", issue = "32838")]
-    #[inline]
-    pub fn allocator(&self) -> &A {
-        self.vec.allocator()
-    }
-}
-
-#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")]
-impl<T, F, A: Allocator> Iterator for ExtractIf<'_, T, F, A>
-where
-    F: FnMut(&mut T) -> bool,
-{
-    type Item = T;
-
-    fn next(&mut self) -> Option<T> {
-        unsafe {
-            while self.idx < self.old_len {
-                let i = self.idx;
-                let v = slice::from_raw_parts_mut(self.vec.as_mut_ptr(), self.old_len);
-                let drained = (self.pred)(&mut v[i]);
-                // Update the index *after* the predicate is called. If the index
-                // is updated prior and the predicate panics, the element at this
-                // index would be leaked.
-                self.idx += 1;
-                if drained {
-                    self.del += 1;
-                    return Some(ptr::read(&v[i]));
-                } else if self.del > 0 {
-                    let del = self.del;
-                    let src: *const T = &v[i];
-                    let dst: *mut T = &mut v[i - del];
-                    ptr::copy_nonoverlapping(src, dst, 1);
-                }
-            }
-            None
-        }
-    }
-
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        (0, Some(self.old_len - self.idx))
-    }
-}
-
-#[unstable(feature = "extract_if", reason = "recently added", issue = "43244")]
-impl<T, F, A: Allocator> Drop for ExtractIf<'_, T, F, A>
-where
-    F: FnMut(&mut T) -> bool,
-{
-    fn drop(&mut self) {
-        unsafe {
-            if self.idx < self.old_len && self.del > 0 {
-                // This is a pretty messed up state, and there isn't really an
-                // obviously right thing to do. We don't want to keep trying
-                // to execute `pred`, so we just backshift all the unprocessed
-                // elements and tell the vec that they still exist. The backshift
-                // is required to prevent a double-drop of the last successfully
-                // drained item prior to a panic in the predicate.
-                let ptr = self.vec.as_mut_ptr();
-                let src = ptr.add(self.idx);
-                let dst = src.sub(self.del);
-                let tail_len = self.old_len - self.idx;
-                src.copy_to(dst, tail_len);
-            }
-            self.vec.set_len(self.old_len - self.del);
-        }
-    }
-}

rust/bindings/bindings_helper.h

@@ -20,5 +20,8 @@
 
 /* `bindgen` gets confused at certain things. */
 const size_t RUST_CONST_HELPER_ARCH_SLAB_MINALIGN = ARCH_SLAB_MINALIGN;
+const gfp_t RUST_CONST_HELPER_GFP_ATOMIC = GFP_ATOMIC;
 const gfp_t RUST_CONST_HELPER_GFP_KERNEL = GFP_KERNEL;
+const gfp_t RUST_CONST_HELPER_GFP_KERNEL_ACCOUNT = GFP_KERNEL_ACCOUNT;
+const gfp_t RUST_CONST_HELPER_GFP_NOWAIT = GFP_NOWAIT;
 const gfp_t RUST_CONST_HELPER___GFP_ZERO = __GFP_ZERO;