Commit f1d3703f authored by Miguel Ojeda's avatar Miguel Ojeda
Browse files

Merge tag 'alloc-next-v6.18-2025-09-04' of https://github.com/Rust-for-Linux/linux into rust-next 

Pull alloc and DMA updates from Danilo Krummrich:

  Allocator:
   - Provide information about the minimum alignment guarantees of
     'Kmalloc', 'Vmalloc' and 'KVmalloc'.
   - Take minimum alignment guarantees of allocators for
     'ForeignOwnable' into account.
   - Remove the 'allocator_test' incl. 'Cmalloc'.

  Box:
   - Implement 'Box::pin_slice()', which constructs a pinned slice of
     elements.

  Vec:
   - Simplify KUnit test module name to 'rust_kvec'.
   - Add doc-test for 'Vec::as_slice()'.
   - Constify various methods.

  DMA:
   - Update 'ARef' and 'AlwaysRefCounted' imports.

  MISC:
   - Remove support for unused host '#[test]'s.
   - Constify 'ArrayLayout::new_unchecked()'.

* tag 'alloc-next-v6.18-2025-09-04' of https://github.com/Rust-for-Linux/linux:
  rust: alloc: remove `allocator_test`
  rust: kernel: remove support for unused host `#[test]`s
  rust: alloc: implement Box::pin_slice()
  rust: alloc: add ARCH_KMALLOC_MINALIGN to bindgen blocklist
  rust: dma: Update ARef and AlwaysRefCounted imports from sync::aref
  rust: alloc: take the allocator into account for FOREIGN_ALIGN
  rust: alloc: specify the minimum alignment of each allocator
  rust: make `kvec::Vec` functions `const fn`
  rust: make `ArrayLayout::new_unchecked` a `const fn`
  rust: alloc: kvec: simplify KUnit test module name to "rust_kvec"
  rust: alloc: kvec: add doc example for as_slice method
parents 76eeb9b8 fe927def

rust/Makefile

+1 −8
Original line number Diff line number Diff line
@@ -248,7 +248,7 @@ quiet_cmd_rustc_test = $(RUSTC_OR_CLIPPY_QUIET) T $< 
	$(objtree)/$(obj)/test/$(subst rusttest-,,$@) $(rust_test_quiet) \

		$(rustc_test_run_flags)



rusttest: rusttest-macros rusttest-kernel

rusttest: rusttest-macros



rusttest-macros: private rustc_target_flags = --extern proc_macro \

	--extern macros --extern kernel --extern pin_init
@@ -258,13 +258,6 @@ rusttest-macros: $(src)/macros/lib.rs \ 
	+$(call if_changed,rustc_test)

	+$(call if_changed,rustdoc_test)



rusttest-kernel: private rustc_target_flags = --extern ffi --extern pin_init \

    --extern build_error --extern macros --extern bindings --extern uapi

rusttest-kernel: $(src)/kernel/lib.rs rusttestlib-ffi rusttestlib-kernel \

    rusttestlib-build_error rusttestlib-macros rusttestlib-bindings \

    rusttestlib-uapi rusttestlib-pin_init FORCE

	+$(call if_changed,rustc_test)



ifdef CONFIG_CC_IS_CLANG

bindgen_c_flags = $(c_flags)

else

rust/bindgen_parameters

+1 −0
Original line number Diff line number Diff line
@@ -34,3 +34,4 @@ 
# We use const helpers to aid bindgen, to avoid conflicts when constants are

# recognized, block generation of the non-helper constants.

--blocklist-item ARCH_SLAB_MINALIGN

--blocklist-item ARCH_KMALLOC_MINALIGN

rust/bindings/bindings_helper.h

+1 −0
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ 


/* `bindgen` gets confused at certain things. */

const size_t RUST_CONST_HELPER_ARCH_SLAB_MINALIGN = ARCH_SLAB_MINALIGN;

const size_t RUST_CONST_HELPER_ARCH_KMALLOC_MINALIGN = ARCH_KMALLOC_MINALIGN;

const size_t RUST_CONST_HELPER_PAGE_SIZE = PAGE_SIZE;

const gfp_t RUST_CONST_HELPER_GFP_ATOMIC = GFP_ATOMIC;

const gfp_t RUST_CONST_HELPER_GFP_KERNEL = GFP_KERNEL;

rust/kernel/alloc.rs

+8 −7
Original line number Diff line number Diff line
@@ -2,18 +2,11 @@ 


//! Implementation of the kernel's memory allocation infrastructure.



#[cfg(not(any(test, testlib)))]

pub mod allocator;

pub mod kbox;

pub mod kvec;

pub mod layout;



#[cfg(any(test, testlib))]

pub mod allocator_test;



#[cfg(any(test, testlib))]

pub use self::allocator_test as allocator;



pub use self::kbox::Box;

pub use self::kbox::KBox;

pub use self::kbox::KVBox;
@@ -137,6 +130,14 @@ pub mod flags { 
/// - Implementers must ensure that all trait functions abide by the guarantees documented in the

///   `# Guarantees` sections.

pub unsafe trait Allocator {

    /// The minimum alignment satisfied by all allocations from this allocator.

    ///

    /// # Guarantees

    ///

    /// Any pointer allocated by this allocator is guaranteed to be aligned to `MIN_ALIGN` even if

    /// the requested layout has a smaller alignment.

    const MIN_ALIGN: usize;



    /// Allocate memory based on `layout` and `flags`.

    ///

    /// On success, returns a buffer represented as `NonNull<[u8]>` that satisfies the layout

rust/kernel/alloc/allocator.rs

+8 −0
Original line number Diff line number Diff line
@@ -17,6 +17,8 @@ 
use crate::bindings;

use crate::pr_warn;



const ARCH_KMALLOC_MINALIGN: usize = bindings::ARCH_KMALLOC_MINALIGN;



/// The contiguous kernel allocator.

///

/// `Kmalloc` is typically used for physically contiguous allocations up to page size, but also
@@ -128,6 +130,8 @@ pub fn aligned_layout(layout: Layout) -> Layout { 
// - passing a pointer to a valid memory allocation is OK,

// - `realloc` satisfies the guarantees, since `ReallocFunc::call` has the same.

unsafe impl Allocator for Kmalloc {

    const MIN_ALIGN: usize = ARCH_KMALLOC_MINALIGN;



    #[inline]

    unsafe fn realloc(

        ptr: Option<NonNull<u8>>,
@@ -147,6 +151,8 @@ unsafe fn realloc( 
// - passing a pointer to a valid memory allocation is OK,

// - `realloc` satisfies the guarantees, since `ReallocFunc::call` has the same.

unsafe impl Allocator for Vmalloc {

    const MIN_ALIGN: usize = kernel::page::PAGE_SIZE;



    #[inline]

    unsafe fn realloc(

        ptr: Option<NonNull<u8>>,
@@ -171,6 +177,8 @@ unsafe fn realloc( 
// - passing a pointer to a valid memory allocation is OK,

// - `realloc` satisfies the guarantees, since `ReallocFunc::call` has the same.

unsafe impl Allocator for KVmalloc {

    const MIN_ALIGN: usize = ARCH_KMALLOC_MINALIGN;



    #[inline]

    unsafe fn realloc(

        ptr: Option<NonNull<u8>>,