Introduce `CpuId::current()`, a constructor that wraps the C function
`raw_smp_processor_id()` to retrieve the current CPU identifier without
guaranteeing stability.
This function should be used only when the caller can ensure that
the CPU ID won't change unexpectedly due to preemption or migration.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Toolchain and infrastructure:
- KUnit '#[test]'s:
- Support KUnit-mapped 'assert!' macros.
The support that landed last cycle was very basic, and the
'assert!' macros panicked since they were the standard library
ones. Now, they are mapped to the KUnit ones in a similar way to
how is done for doctests, reusing the infrastructure there.
With this, a failing test like:
#[test]
fn my_first_test() {
assert_eq!(42, 43);
}
will report:
# my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251
Expected 42 == 43 to be true, but is false
# my_first_test.speed: normal
not ok 1 my_first_test
- Support tests with checked 'Result' return types.
The return value of test functions that return a 'Result' will be
checked, thus one can now easily catch errors when e.g. using the
'?' operator in tests.
With this, a failing test like:
#[test]
fn my_test() -> Result {
f()?;
Ok(())
}
will report:
# my_test: ASSERTION FAILED at rust/kernel/lib.rs:321
Expected is_test_result_ok(my_test()) to be true, but is false
# my_test.speed: normal
not ok 1 my_test
- Add 'kunit_tests' to the prelude.
- Clarify the remaining language unstable features in use.
- Compile 'core' with edition 2024 for Rust >= 1.87.
- Workaround 'bindgen' issue with forward references to 'enum' types.
- objtool: relax slice condition to cover more 'noreturn' functions.
- Use absolute paths in macros referencing 'core' and 'kernel' crates.
- Skip '-mno-fdpic' flag for bindgen in GCC 32-bit arm builds.
- Clean some 'doc_markdown' lint hits -- we may enable it later on.
'kernel' crate:
- 'alloc' module:
- 'Box': support for type coercion, e.g. 'Box<T>' to 'Box<dyn U>' if
'T' implements 'U'.
- 'Vec': implement new methods (prerequisites for nova-core and
binder): 'truncate', 'resize', 'clear', 'pop',
'push_within_capacity' (with new error type 'PushError'),
'drain_all', 'retain', 'remove' (with new error type
'RemoveError'), insert_within_capacity' (with new error type
'InsertError').
In addition, simplify 'push' using 'spare_capacity_mut', split
'set_len' into 'inc_len' and 'dec_len', add type invariant
'len <= capacity' and simplify 'truncate' using 'dec_len'.
- 'time' module:
- Morph the Rust hrtimer subsystem into the Rust timekeeping
subsystem, covering delay, sleep, timekeeping, timers. This new
subsystem has all the relevant timekeeping C maintainers listed in
the entry.
- Replace 'Ktime' with 'Delta' and 'Instant' types to represent a
duration of time and a point in time.
- Temporarily add 'Ktime' to 'hrtimer' module to allow 'hrtimer' to
delay converting to 'Instant' and 'Delta'.
- 'xarray' module:
- 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.
- Allow 'ForeignOwnable' to carry information about the pointed-to
type. This helps asserting alignment requirements for the pointer
passed to the foreign language.
- 'container_of!': retain pointer mut-ness and add a compile-time check
of the type of the first parameter ('$field_ptr').
- Support optional message in 'static_assert!'.
- Add C FFI types (e.g. 'c_int') to the prelude.
- 'str' module: simplify KUnit tests 'format!' macro, convert
'rusttest' tests into KUnit, take advantage of the '-> Result'
support in KUnit '#[test]'s.
- 'list' module: add examples for 'List', fix path of 'assert_pinned!'
(so far unused macro rule).
- 'workqueue' module: remove 'HasWork::OFFSET'.
- 'page' module: add 'inline' attribute.
'macros' crate:
- 'module' macro: place 'cleanup_module()' in '.exit.text' section.
'pin-init' crate:
- Add 'Wrapper<T>' trait for creating pin-initializers for wrapper
structs with a structurally pinned value such as 'UnsafeCell<T>' or
'MaybeUninit<T>'.
- Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but
not error if not all fields implement it. This is needed to derive
'Zeroable' for all bindgen-generated structs.
- Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the
initialized type of an initializer. These are utilized by the
'Wrapper<T>' implementations.
- Add support for visibility in 'Zeroable' derive macro.
- Add support for 'union's in 'Zeroable' derive macro.
- Upstream dev news: streamline CI, fix some bugs. Add new workflows
to check if the user-space version and the one in the kernel tree
have diverged. Use the issues tab [1] to track them, which should
help folks report and diagnose issues w.r.t. 'pin-init' better.
[1] https://github.com/rust-for-linux/pin-init/issues
Documentation:
- Testing: add docs on the new KUnit '#[test]' tests.
- Coding guidelines: explain that '///' vs. '//' applies to private
items too. Add section on C FFI types.
- Quick Start guide: update Ubuntu instructions and split them into
"25.04" and "24.04 LTS and older".
And a few other cleanups and improvements.
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Merge tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- KUnit '#[test]'s:
- Support KUnit-mapped 'assert!' macros.
The support that landed last cycle was very basic, and the
'assert!' macros panicked since they were the standard library
ones. Now, they are mapped to the KUnit ones in a similar way to
how is done for doctests, reusing the infrastructure there.
With this, a failing test like:
#[test]
fn my_first_test() {
assert_eq!(42, 43);
}
will report:
# my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251
Expected 42 == 43 to be true, but is false
# my_first_test.speed: normal
not ok 1 my_first_test
- Support tests with checked 'Result' return types.
The return value of test functions that return a 'Result' will
be checked, thus one can now easily catch errors when e.g. using
the '?' operator in tests.
With this, a failing test like:
#[test]
fn my_test() -> Result {
f()?;
Ok(())
}
will report:
# my_test: ASSERTION FAILED at rust/kernel/lib.rs:321
Expected is_test_result_ok(my_test()) to be true, but is false
# my_test.speed: normal
not ok 1 my_test
- Add 'kunit_tests' to the prelude.
- Clarify the remaining language unstable features in use.
- Compile 'core' with edition 2024 for Rust >= 1.87.
- Workaround 'bindgen' issue with forward references to 'enum' types.
- objtool: relax slice condition to cover more 'noreturn' functions.
- Use absolute paths in macros referencing 'core' and 'kernel'
crates.
- Skip '-mno-fdpic' flag for bindgen in GCC 32-bit arm builds.
- Clean some 'doc_markdown' lint hits -- we may enable it later on.
'kernel' crate:
- 'alloc' module:
- 'Box': support for type coercion, e.g. 'Box<T>' to 'Box<dyn U>'
if 'T' implements 'U'.
- 'Vec': implement new methods (prerequisites for nova-core and
binder): 'truncate', 'resize', 'clear', 'pop',
'push_within_capacity' (with new error type 'PushError'),
'drain_all', 'retain', 'remove' (with new error type
'RemoveError'), insert_within_capacity' (with new error type
'InsertError').
In addition, simplify 'push' using 'spare_capacity_mut', split
'set_len' into 'inc_len' and 'dec_len', add type invariant 'len
<= capacity' and simplify 'truncate' using 'dec_len'.
- 'time' module:
- Morph the Rust hrtimer subsystem into the Rust timekeeping
subsystem, covering delay, sleep, timekeeping, timers. This new
subsystem has all the relevant timekeeping C maintainers listed
in the entry.
- Replace 'Ktime' with 'Delta' and 'Instant' types to represent a
duration of time and a point in time.
- Temporarily add 'Ktime' to 'hrtimer' module to allow 'hrtimer'
to delay converting to 'Instant' and 'Delta'.
- 'xarray' module:
- 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.
- Allow 'ForeignOwnable' to carry information about the pointed-to
type. This helps asserting alignment requirements for the
pointer passed to the foreign language.
- 'container_of!': retain pointer mut-ness and add a compile-time
check of the type of the first parameter ('$field_ptr').
- Support optional message in 'static_assert!'.
- Add C FFI types (e.g. 'c_int') to the prelude.
- 'str' module: simplify KUnit tests 'format!' macro, convert
'rusttest' tests into KUnit, take advantage of the '-> Result'
support in KUnit '#[test]'s.
- 'list' module: add examples for 'List', fix path of
'assert_pinned!' (so far unused macro rule).
- 'workqueue' module: remove 'HasWork::OFFSET'.
- 'page' module: add 'inline' attribute.
'macros' crate:
- 'module' macro: place 'cleanup_module()' in '.exit.text' section.
'pin-init' crate:
- Add 'Wrapper<T>' trait for creating pin-initializers for wrapper
structs with a structurally pinned value such as 'UnsafeCell<T>' or
'MaybeUninit<T>'.
- Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but
not error if not all fields implement it. This is needed to derive
'Zeroable' for all bindgen-generated structs.
- Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the
initialized type of an initializer. These are utilized by the
'Wrapper<T>' implementations.
- Add support for visibility in 'Zeroable' derive macro.
- Add support for 'union's in 'Zeroable' derive macro.
- Upstream dev news: streamline CI, fix some bugs. Add new workflows
to check if the user-space version and the one in the kernel tree
have diverged. Use the issues tab [1] to track them, which should
help folks report and diagnose issues w.r.t. 'pin-init' better.
[1] https://github.com/rust-for-linux/pin-init/issues
Documentation:
- Testing: add docs on the new KUnit '#[test]' tests.
- Coding guidelines: explain that '///' vs. '//' applies to private
items too. Add section on C FFI types.
- Quick Start guide: update Ubuntu instructions and split them into
"25.04" and "24.04 LTS and older".
And a few other cleanups and improvements"
* tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (78 commits)
rust: list: Fix typo `much` in arc.rs
rust: check type of `$ptr` in `container_of!`
rust: workqueue: remove HasWork::OFFSET
rust: retain pointer mut-ness in `container_of!`
Documentation: rust: testing: add docs on the new KUnit `#[test]` tests
Documentation: rust: rename `#[test]`s to "`rusttest` host tests"
rust: str: take advantage of the `-> Result` support in KUnit `#[test]`'s
rust: str: simplify KUnit tests `format!` macro
rust: str: convert `rusttest` tests into KUnit
rust: add `kunit_tests` to the prelude
rust: kunit: support checked `-> Result`s in KUnit `#[test]`s
rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s
rust: make section names plural
rust: list: fix path of `assert_pinned!`
rust: compile libcore with edition 2024 for 1.87+
rust: dma: add missing Markdown code span
rust: task: add missing Markdown code spans and intra-doc links
rust: pci: fix docs related to missing Markdown code spans
rust: alloc: add missing Markdown code span
rust: alloc: add missing Markdown code spans
...
simplifies the act of creating a pte which addresses the first page in a
folio and reduces the amount of plumbing which architecture must
implement to provide this.
- The 8 patch series "Misc folio patches for 6.16" from Matthew Wilcox
is a shower of largely unrelated folio infrastructure changes which
clean things up and better prepare us for future work.
- The 3 patch series "memory,x86,acpi: hotplug memory alignment
advisement" from Gregory Price adds early-init code to prevent x86 from
leaving physical memory unused when physical address regions are not
aligned to memory block size.
- The 2 patch series "mm/compaction: allow more aggressive proactive
compaction" from Michal Clapinski provides some tuning of the (sadly,
hard-coded (more sadly, not auto-tuned)) thresholds for our invokation
of proactive compaction. In a simple test case, the reduction of a guest
VM's memory consumption was dramatic.
- The 8 patch series "Minor cleanups and improvements to swap freeing
code" from Kemeng Shi provides some code cleaups and a small efficiency
improvement to this part of our swap handling code.
- The 6 patch series "ptrace: introduce PTRACE_SET_SYSCALL_INFO API"
from Dmitry Levin adds the ability for a ptracer to modify syscalls
arguments. At this time we can alter only "system call information that
are used by strace system call tampering, namely, syscall number,
syscall arguments, and syscall return value.
This series should have been incorporated into mm.git's "non-MM"
branch, but I goofed.
- The 3 patch series "fs/proc: extend the PAGEMAP_SCAN ioctl to report
guard regions" from Andrei Vagin extends the info returned by the
PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more
efficiently get at the info about guard regions.
- The 2 patch series "Fix parameter passed to page_mapcount_is_type()"
from Gavin Shan implements that fix. No runtime effect is expected
because validate_page_before_insert() happens to fix up this error.
- The 3 patch series "kernel/events/uprobes: uprobe_write_opcode()
rewrite" from David Hildenbrand basically brings uprobe text poking into
the current decade. Remove a bunch of hand-rolled implementation in
favor of using more current facilities.
- The 3 patch series "mm/ptdump: Drop assumption that pxd_val() is u64"
from Anshuman Khandual provides enhancements and generalizations to the
pte dumping code. This might be needed when 128-bit Page Table
Descriptors are enabled for ARM.
- The 12 patch series "Always call constructor for kernel page tables"
from Kevin Brodsky "ensures that the ctor/dtor is always called for
kernel pgtables, as it already is for user pgtables". This permits the
addition of more functionality such as "insert hooks to protect page
tables". This change does result in various architectures performing
unnecesary work, but this is fixed up where it is anticipated to occur.
- The 9 patch series "Rust support for mm_struct, vm_area_struct, and
mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM
structures.
- The 3 patch series "fix incorrectly disallowed anonymous VMA merges"
from Lorenzo Stoakes takes advantage of some VMA merging opportunities
which we've been missing for 15 years.
- The 4 patch series "mm/madvise: batch tlb flushes for MADV_DONTNEED
and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB
flushing. Instead of flushing each address range in the provided iovec,
we batch the flushing across all the iovec entries. The syscall's cost
was approximately halved with a microbenchmark which was designed to
load this particular operation.
- The 6 patch series "Track node vacancy to reduce worst case allocation
counts" from Sidhartha Kumar makes the maple tree smarter about its node
preallocation. stress-ng mmap performance increased by single-digit
percentages and the amount of unnecessarily preallocated memory was
dramaticelly reduced.
- The 3 patch series "mm/gup: Minor fix, cleanup and improvements" from
Baoquan He removes a few unnecessary things which Baoquan noted when
reading the code.
- The 3 patch series ""Enhance sysfs handling for memory hotplug in
weighted interleave" from Rakie Kim "enhances the weighted interleave
policy in the memory management subsystem by improving sysfs handling,
fixing memory leaks, and introducing dynamic sysfs updates for memory
hotplug support". Fixes things on error paths which we are unlikely to
hit.
- The 7 patch series "mm/damon: auto-tune DAMOS for NUMA setups
including tiered memory" from SeongJae Park introduces new DAMOS quota
goal metrics which eliminate the manual tuning which is required when
utilizing DAMON for memory tiering.
- The 5 patch series "mm/vmalloc.c: code cleanup and improvements" from
Baoquan He provides cleanups and small efficiency improvements which
Baoquan found via code inspection.
- The 2 patch series "vmscan: enforce mems_effective during demotion"
from Gregory Price "changes reclaim to respect cpuset.mems_effective
during demotion when possible". because "presently, reclaim explicitly
ignores cpuset.mems_effective when demoting, which may cause the cpuset
settings to violated." "This is useful for isolating workloads on a
multi-tenant system from certain classes of memory more consistently."
- The 2 patch series ""Clean up split_huge_pmd_locked() and remove
unnecessary folio pointers" from Gavin Guo provides minor cleanups and
efficiency gains in in the huge page splitting and migrating code.
- The 3 patch series "Use kmem_cache for memcg alloc" from Huan Yang
creates a slab cache for `struct mem_cgroup', yielding improved memory
utilization.
- The 4 patch series "add max arg to swappiness in memory.reclaim and
lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness="
argument for memory.reclaim MGLRU's lru_gen. This directs proactive
reclaim to reclaim from only anon folios rather than file-backed folios.
- The 17 patch series "kexec: introduce Kexec HandOver (KHO)" from Mike
Rapoport is the first step on the path to permitting the kernel to
maintain existing VMs while replacing the host kernel via file-based
kexec. At this time only memblock's reserve_mem is preserved.
- The 7 patch series "mm: Introduce for_each_valid_pfn()" from David
Woodhouse provides and uses a smarter way of looping over a pfn range.
By skipping ranges of invalid pfns.
- The 2 patch series "sched/numa: Skip VMA scanning on memory pinned to
one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless
VMA scanning when a task is pinned a single NUMA mode. Dramatic
performance benefits were seen in some real world cases.
- The 2 patch series "JFS: Implement migrate_folio for
jfs_metapage_aops" from Shivank Garg addresses a warning which occurs
during memory compaction when using JFS.
- The 4 patch series "move all VMA allocation, freeing and duplication
logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c
into the more appropriate mm/vma.c.
- The 6 patch series "mm, swap: clean up swap cache mapping helper" from
Kairui Song provides code consolidation and cleanups related to the
folio_index() function.
- The 2 patch series "mm/gup: Cleanup memfd_pin_folios()" from Vishal
Moola does that.
- The 8 patch series "memcg: Fix test_memcg_min/low test failures" from
Waiman Long addresses some bogus failures which are being reported by
the test_memcontrol selftest.
- The 3 patch series "eliminate mmap() retry merge, add .mmap_prepare
hook" from Lorenzo Stoakes commences the deprecation of
file_operations.mmap() in favor of the new
file_operations.mmap_prepare(). The latter is more restrictive and
prevents drivers from messing with things in ways which, amongst other
problems, may defeat VMA merging.
- The 4 patch series "memcg: decouple memcg and objcg stocks"" from
Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's
one. This is a step along the way to making memcg and objcg charging
NMI-safe, which is a BPF requirement.
- The 6 patch series "mm/damon: minor fixups and improvements for code,
tests, and documents" from SeongJae Park is "yet another batch of
miscellaneous DAMON changes. Fix and improve minor problems in code,
tests and documents."
- The 7 patch series "memcg: make memcg stats irq safe" from Shakeel
Butt converts memcg stats to be irq safe. Another step along the way to
making memcg charging and stats updates NMI-safe, a BPF requirement.
- The 4 patch series "Let unmap_hugepage_range() and several related
functions take folio instead of page" from Fan Ni provides folio
conversions in the hugetlb code.
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Merge tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of
creating a pte which addresses the first page in a folio and reduces
the amount of plumbing which architecture must implement to provide
this.
- "Misc folio patches for 6.16" from Matthew Wilcox is a shower of
largely unrelated folio infrastructure changes which clean things up
and better prepare us for future work.
- "memory,x86,acpi: hotplug memory alignment advisement" from Gregory
Price adds early-init code to prevent x86 from leaving physical
memory unused when physical address regions are not aligned to memory
block size.
- "mm/compaction: allow more aggressive proactive compaction" from
Michal Clapinski provides some tuning of the (sadly, hard-coded (more
sadly, not auto-tuned)) thresholds for our invokation of proactive
compaction. In a simple test case, the reduction of a guest VM's
memory consumption was dramatic.
- "Minor cleanups and improvements to swap freeing code" from Kemeng
Shi provides some code cleaups and a small efficiency improvement to
this part of our swap handling code.
- "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin
adds the ability for a ptracer to modify syscalls arguments. At this
time we can alter only "system call information that are used by
strace system call tampering, namely, syscall number, syscall
arguments, and syscall return value.
This series should have been incorporated into mm.git's "non-MM"
branch, but I goofed.
- "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from
Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl
against /proc/pid/pagemap. This permits CRIU to more efficiently get
at the info about guard regions.
- "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan
implements that fix. No runtime effect is expected because
validate_page_before_insert() happens to fix up this error.
- "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David
Hildenbrand basically brings uprobe text poking into the current
decade. Remove a bunch of hand-rolled implementation in favor of
using more current facilities.
- "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman
Khandual provides enhancements and generalizations to the pte dumping
code. This might be needed when 128-bit Page Table Descriptors are
enabled for ARM.
- "Always call constructor for kernel page tables" from Kevin Brodsky
ensures that the ctor/dtor is always called for kernel pgtables, as
it already is for user pgtables.
This permits the addition of more functionality such as "insert hooks
to protect page tables". This change does result in various
architectures performing unnecesary work, but this is fixed up where
it is anticipated to occur.
- "Rust support for mm_struct, vm_area_struct, and mmap" from Alice
Ryhl adds plumbing to permit Rust access to core MM structures.
- "fix incorrectly disallowed anonymous VMA merges" from Lorenzo
Stoakes takes advantage of some VMA merging opportunities which we've
been missing for 15 years.
- "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from
SeongJae Park optimizes process_madvise()'s TLB flushing.
Instead of flushing each address range in the provided iovec, we
batch the flushing across all the iovec entries. The syscall's cost
was approximately halved with a microbenchmark which was designed to
load this particular operation.
- "Track node vacancy to reduce worst case allocation counts" from
Sidhartha Kumar makes the maple tree smarter about its node
preallocation.
stress-ng mmap performance increased by single-digit percentages and
the amount of unnecessarily preallocated memory was dramaticelly
reduced.
- "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes
a few unnecessary things which Baoquan noted when reading the code.
- ""Enhance sysfs handling for memory hotplug in weighted interleave"
from Rakie Kim "enhances the weighted interleave policy in the memory
management subsystem by improving sysfs handling, fixing memory
leaks, and introducing dynamic sysfs updates for memory hotplug
support". Fixes things on error paths which we are unlikely to hit.
- "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory"
from SeongJae Park introduces new DAMOS quota goal metrics which
eliminate the manual tuning which is required when utilizing DAMON
for memory tiering.
- "mm/vmalloc.c: code cleanup and improvements" from Baoquan He
provides cleanups and small efficiency improvements which Baoquan
found via code inspection.
- "vmscan: enforce mems_effective during demotion" from Gregory Price
changes reclaim to respect cpuset.mems_effective during demotion when
possible. because presently, reclaim explicitly ignores
cpuset.mems_effective when demoting, which may cause the cpuset
settings to violated.
This is useful for isolating workloads on a multi-tenant system from
certain classes of memory more consistently.
- "Clean up split_huge_pmd_locked() and remove unnecessary folio
pointers" from Gavin Guo provides minor cleanups and efficiency gains
in in the huge page splitting and migrating code.
- "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache
for `struct mem_cgroup', yielding improved memory utilization.
- "add max arg to swappiness in memory.reclaim and lru_gen" from
Zhongkun He adds a new "max" argument to the "swappiness=" argument
for memory.reclaim MGLRU's lru_gen.
This directs proactive reclaim to reclaim from only anon folios
rather than file-backed folios.
- "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the
first step on the path to permitting the kernel to maintain existing
VMs while replacing the host kernel via file-based kexec. At this
time only memblock's reserve_mem is preserved.
- "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides
and uses a smarter way of looping over a pfn range. By skipping
ranges of invalid pfns.
- "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via
cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning
when a task is pinned a single NUMA mode.
Dramatic performance benefits were seen in some real world cases.
- "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank
Garg addresses a warning which occurs during memory compaction when
using JFS.
- "move all VMA allocation, freeing and duplication logic to mm" from
Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more
appropriate mm/vma.c.
- "mm, swap: clean up swap cache mapping helper" from Kairui Song
provides code consolidation and cleanups related to the folio_index()
function.
- "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that.
- "memcg: Fix test_memcg_min/low test failures" from Waiman Long
addresses some bogus failures which are being reported by the
test_memcontrol selftest.
- "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo
Stoakes commences the deprecation of file_operations.mmap() in favor
of the new file_operations.mmap_prepare().
The latter is more restrictive and prevents drivers from messing with
things in ways which, amongst other problems, may defeat VMA merging.
- "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples
the per-cpu memcg charge cache from the objcg's one.
This is a step along the way to making memcg and objcg charging
NMI-safe, which is a BPF requirement.
- "mm/damon: minor fixups and improvements for code, tests, and
documents" from SeongJae Park is yet another batch of miscellaneous
DAMON changes. Fix and improve minor problems in code, tests and
documents.
- "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg
stats to be irq safe. Another step along the way to making memcg
charging and stats updates NMI-safe, a BPF requirement.
- "Let unmap_hugepage_range() and several related functions take folio
instead of page" from Fan Ni provides folio conversions in the
hugetlb code.
* tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits)
mm: pcp: increase pcp->free_count threshold to trigger free_high
mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range()
mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page
mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page
mm/hugetlb: pass folio instead of page to unmap_ref_private()
memcg: objcg stock trylock without irq disabling
memcg: no stock lock for cpu hot-unplug
memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs
memcg: make count_memcg_events re-entrant safe against irqs
memcg: make mod_memcg_state re-entrant safe against irqs
memcg: move preempt disable to callers of memcg_rstat_updated
memcg: memcg_rstat_updated re-entrant safe against irqs
mm: khugepaged: decouple SHMEM and file folios' collapse
selftests/eventfd: correct test name and improve messages
alloc_tag: check mem_profiling_support in alloc_tag_init
Docs/damon: update titles and brief introductions to explain DAMOS
selftests/damon/_damon_sysfs: read tried regions directories in order
mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject()
mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat()
mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs
...
Merge Rust support for cpufreq and OPP, a new Rust-based cpufreq-dt
driver, an SCMI cpufreq driver cleanup, and an ACPI cpufreq driver
regression fix:
- Add Rust abstractions for CPUFreq framework (Viresh Kumar).
- Add Rust abstractions for OPP framework (Viresh Kumar).
- Add basic Rust abstractions for Clk and Cpumask frameworks (Viresh
Kumar).
- Clean up the SCMI cpufreq driver somewhat (Mike Tipton).
- Use KHz as the nominal_freq units in get_max_boost_ratio() in the
ACPI cpufreq driver (iGautham Shenoy).
* pm-cpufreq:
acpi-cpufreq: Fix nominal_freq units to KHz in get_max_boost_ratio()
rust: opp: Move `cfg(CONFIG_OF)` attribute to the top of doc test
rust: opp: Make the doctest example depend on CONFIG_OF
cpufreq: scmi: Skip SCMI devices that aren't used by the CPUs
cpufreq: Add Rust-based cpufreq-dt driver
rust: opp: Extend OPP abstractions with cpufreq support
rust: cpufreq: Extend abstractions for driver registration
rust: cpufreq: Extend abstractions for policy and driver ops
rust: cpufreq: Add initial abstractions for cpufreq framework
rust: opp: Add abstractions for the configuration options
rust: opp: Add abstractions for the OPP table
rust: opp: Add initial abstractions for OPP framework
rust: cpu: Add from_cpu()
rust: macros: enable use of hyphens in module names
rust: clk: Add initial abstractions
rust: clk: Add helpers for Rust code
MAINTAINERS: Add entry for Rust cpumask API
rust: cpumask: Add initial abstractions
rust: cpumask: Add few more helpers
- Rust abstractions for CPUFreq framework (Viresh Kumar).
- Rust abstractions for OPP framework (Viresh Kumar).
- Basic Rust abstractions for Clk and Cpumask frameworks (Viresh Kumar).
- Minor cleanup to the SCMI cpufreq driver (Mike Tipton).
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Merge tag 'cpufreq-arm-updates-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm
Merge ARM CPUFreq updates for 6.16 from Viresh Kumar:
"- Rust abstractions for CPUFreq framework (Viresh Kumar).
- Rust abstractions for OPP framework (Viresh Kumar).
- Basic Rust abstractions for Clk and Cpumask frameworks (Viresh Kumar).
- Minor cleanup to the SCMI cpufreq driver (Mike Tipton)."
* tag 'cpufreq-arm-updates-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: (24 commits)
cpufreq: scmi: Skip SCMI devices that aren't used by the CPUs
cpufreq: Add Rust-based cpufreq-dt driver
rust: opp: Extend OPP abstractions with cpufreq support
rust: cpufreq: Extend abstractions for driver registration
rust: cpufreq: Extend abstractions for policy and driver ops
rust: cpufreq: Add initial abstractions for cpufreq framework
rust: opp: Add abstractions for the configuration options
rust: opp: Add abstractions for the OPP table
rust: opp: Add initial abstractions for OPP framework
rust: cpu: Add from_cpu()
rust: macros: enable use of hyphens in module names
rust: clk: Add initial abstractions
rust: clk: Add helpers for Rust code
MAINTAINERS: Add entry for Rust cpumask API
rust: cpumask: Add initial abstractions
rust: cpumask: Add few more helpers
rust: devres: require a bound device
rust: pci: move iomap_region() to impl Device<Bound>
rust: device: implement Bound device context
rust: pci: preserve device context in AsRef
...
Introduce initial Rust abstractions for the cpufreq core. This includes
basic representations for cpufreq flags, relation types, and the cpufreq
table.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Non-trivial C macros and inlined C functions cannot be used directly
in the Rust code and are used via functions ("helpers") that wrap
those so that they can be called from Rust.
In order to prepare for adding Rust abstractions for the clock APIs,
add clock helpers required by the Rust implementation.
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Patch series "Rust support for mm_struct, vm_area_struct, and mmap", v16.
This updates the vm_area_struct support to use the approach we discussed
at LPC where there are several different Rust wrappers for vm_area_struct
depending on the kind of access you have to the vma. Each case allows a
different set of operations on the vma.
This includes an MM MAINTAINERS entry as proposed by Lorenzo:
https://lore.kernel.org/all/33e64b12-aa07-4e78-933a-b07c37ff1d84@lucifer.local/
This patch (of 9):
These abstractions allow you to reference a `struct mm_struct` using both
mmgrab and mmget refcounts. This is done using two Rust types:
* Mm - represents an mm_struct where you don't know anything about the
value of mm_users.
* MmWithUser - represents an mm_struct where you know at compile time
that mm_users is non-zero.
This allows us to encode in the type system whether a method requires that
mm_users is non-zero or not. For instance, you can always call
`mmget_not_zero` but you can only call `mmap_read_lock` when mm_users is
non-zero.
The struct is called Mm to keep consistency with the C side.
The ability to obtain `current->mm` is added later in this series.
The mm module is defined to only exist when CONFIG_MMU is set. This
avoids various errors due to missing types and functions when CONFIG_MMU
is disabled. More fine-grained cfgs can be considered in the future. See
the thread at [1] for more info.
Link: https://lkml.kernel.org/r/20250408-vma-v16-9-d8b446e885d9@google.com
Link: https://lkml.kernel.org/r/20250408-vma-v16-1-d8b446e885d9@google.com
Link: https://lore.kernel.org/all/202503091916.QousmtcY-lkp@intel.com/
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Balbir Singh <balbirs@nvidia.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jann Horn <jannh@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
`XArray` is an efficient sparse array of pointers. Add a Rust
abstraction for this type.
This implementation bounds the element type on `ForeignOwnable` and
requires explicit locking for all operations. Future work may leverage
RCU to enable lockless operation.
Inspired-by: Maíra Canal <mcanal@igalia.com>
Inspired-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250423-rust-xarray-bindings-v19-2-83cdcf11c114@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
DRM GEM is the DRM memory management subsystem used by most modern
drivers; add a Rust abstraction for DRM GEM.
This includes the BaseObject trait, which contains operations shared by
all GEM object classes.
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-8-dakr@kernel.org
[ Rework of GEM object abstractions
* switch to the Opaque<T> type
* fix (mutable) references to struct drm_gem_object (which in this
context is UB)
* drop all custom reference types in favor of AlwaysRefCounted
* bunch of minor changes and simplifications (e.g. IntoGEMObject
trait)
* write and fix safety and invariant comments
* remove necessity for and convert 'as' casts
* original source archive: https://archive.is/dD5SL
- Danilo ]
[ Fix missing CONFIG_DRM guards in rust/helpers/drm.c. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement the basic auxiliary abstractions required to implement a
driver matching an auxiliary device.
The design and implementation is analogous to PCI and platform and is
based on the generic device / driver abstractions.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250414131934.28418-4-dakr@kernel.org
[ Fix typos, `let _ =` => `drop()`, use `kernel::ffi`. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Add dma_alloc_attrs() and dma_free_attrs() helpers to fix a build
error when CONFIG_HAS_DMA is not enabled.
Note that when CONFIG_HAS_DMA is enabled, dma_alloc_attrs() and
dma_free_attrs() are included in both bindings_generated.rs and
bindings_helpers_generated.rs. The former takes precedence so behavior
remains unchanged in that case.
This fixes the following build error on UML:
error[E0425]: cannot find function `dma_alloc_attrs` in crate `bindings`
--> rust/kernel/dma.rs:171:23
|
171 | bindings::dma_alloc_attrs(
| ^^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_alloc_pages`
|
::: rust/bindings/bindings_generated.rs:44568:5
|
44568 | / pub fn dma_alloc_pages(
44569 | | dev: *mut device,
44570 | | size: usize,
44571 | | dma_handle: *mut dma_addr_t,
44572 | | dir: dma_data_direction,
44573 | | gfp: gfp_t,
44574 | | ) -> *mut page;
| |___________________- similarly named function `dma_alloc_pages` defined here
error[E0425]: cannot find function `dma_free_attrs` in crate `bindings`
--> rust/kernel/dma.rs:293:23
|
293 | bindings::dma_free_attrs(
| ^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_free_pages`
|
::: rust/bindings/bindings_generated.rs:44577:5
|
44577 | / pub fn dma_free_pages(
44578 | | dev: *mut device,
44579 | | size: usize,
44580 | | page: *mut page,
44581 | | dma_handle: dma_addr_t,
44582 | | dir: dma_data_direction,
44583 | | );
| |______- similarly named function `dma_free_pages` defined here
Fixes: ad2907b4e3 ("rust: add dma coherent allocator abstraction")
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250412000507.157000-1-fujita.tomonori@gmail.com
[ Reworded for relative paths. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reintroduce dynamically-allocated LockClassKeys such that they are
automatically (de)registered. Require that all usages of LockClassKeys
ensure that they are Pin'd.
Currently, only `'static` LockClassKeys are supported, so Pin is
redundant. However, it is intended that dynamically-allocated
LockClassKeys will eventually be supported, so using Pin from the outset
will make that change simpler.
Closes: https://github.com/Rust-for-Linux/linux/issues/1102
Suggested-by: Benno Lossin <benno.lossin@proton.me>
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Mitchell Levy <levymitchell0@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250307232717.1759087-12-boqun.feng@gmail.com
In order to prepare for adding Rust abstractions for cpumask, add
the required helpers for inline cpumask functions that cannot be
called by rust code directly.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
Implement the basic platform bus abstractions required to write a basic
platform driver. This includes the following data structures:
The `platform::Driver` trait represents the interface to the driver and
provides `platform::Driver::probe` for the driver to implement.
The `platform::Device` abstraction represents a `struct platform_device`.
In order to provide the platform bus specific parts to a generic
`driver::Registration` the `driver::RegistrationOps` trait is implemented
by `platform::Adapter`.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-15-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the basic PCI abstractions required to write a basic PCI
driver. This includes the following data structures:
The `pci::Driver` trait represents the interface to the driver and
provides `pci::Driver::probe` for the driver to implement.
The `pci::Device` abstraction represents a `struct pci_dev` and provides
abstractions for common functions, such as `pci::Device::set_master`.
In order to provide the PCI specific parts to a generic
`driver::Registration` the `driver::RegistrationOps` trait is implemented
by `pci::Adapter`.
`pci::DeviceId` implements PCI device IDs based on the generic
`device_id::RawDevceId` abstraction.
Co-developed-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-10-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a Rust abstraction for the kernel's devres (device resource
management) implementation.
The Devres type acts as a container to manage the lifetime and
accessibility of device bound resources. Therefore it registers a
devres callback and revokes access to the resource on invocation.
Users of the Devres abstraction can simply free the corresponding
resources in their Drop implementation, which is invoked when either the
Devres instance goes out of scope or the devres callback leads to the
resource being revoked, which implies a call to drop_in_place().
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-9-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I/O memory is typically either mapped through direct calls to ioremap()
or subsystem / bus specific ones such as pci_iomap().
Even though subsystem / bus specific functions to map I/O memory are
based on ioremap() / iounmap() it is not desirable to re-implement them
in Rust.
Instead, implement a base type for I/O mapped memory, which generically
provides the corresponding accessors, such as `Io::readb` or
`Io:try_readb`.
`Io` supports an optional const generic, such that a driver can indicate
the minimal expected and required size of the mapping at compile time.
Correspondingly, calls to the 'non-try' accessors, support compile time
checks of the I/O memory offset to read / write, while the 'try'
accessors, provide boundary checks on runtime.
`IoRaw` is meant to be embedded into a structure (e.g. pci::Bar or
io::IoMem) which creates the actual I/O memory mapping and initializes
`IoRaw` accordingly.
To ensure that I/O mapped memory can't out-live the device it may be
bound to, subsystems must embed the corresponding I/O memory type (e.g.
pci::Bar) into a `Devres` container, such that it gets revoked once the
device is unbound.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-8-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Toolchain and infrastructure:
- Enable a series of lints, including safety-related ones, e.g. the
compiler will now warn about missing safety comments, as well as
unnecessary ones. How safety documentation is organized is a frequent
source of review comments, thus having the compiler guide new
developers on where they are expected (and where not) is very nice.
- Start using '#[expect]': an interesting feature in Rust (stabilized
in 1.81.0) that makes the compiler warn if an expected warning was
_not_ emitted. This is useful to avoid forgetting cleaning up locally
ignored diagnostics ('#[allow]'s).
- Introduce '.clippy.toml' configuration file for Clippy, the Rust
linter, which will allow us to tweak its behaviour. For instance, our
first use cases are declaring a disallowed macro and, more
importantly, enabling the checking of private items.
- Lints-related fixes and cleanups related to the items above.
- Migrate from 'receiver_trait' to 'arbitrary_self_types': to get the
kernel into stable Rust, one of the major pieces of the puzzle is the
support to write custom types that can be used as 'self', i.e. as
receivers, since the kernel needs to write types such as 'Arc' that
common userspace Rust would not. 'arbitrary_self_types' has been
accepted to become stable, and this is one of the steps required to
get there.
- Remove usage of the 'new_uninit' unstable feature.
- Use custom C FFI types. Includes a new 'ffi' crate to contain our
custom mapping, instead of using the standard library 'core::ffi'
one. The actual remapping will be introduced in a later cycle.
- Map '__kernel_{size_t,ssize_t,ptrdiff_t}' to 'usize'/'isize' instead
of 32/64-bit integers.
- Fix 'size_t' in bindgen generated prototypes of C builtins.
- Warn on bindgen < 0.69.5 and libclang >= 19.1 due to a double issue
in the projects, which we managed to trigger with the upcoming
tracepoint support. It includes a build test since some distributions
backported the fix (e.g. Debian -- thanks!). All major distributions
we list should be now OK except Ubuntu non-LTS.
'macros' crate:
- Adapt the build system to be able run the doctests there too; and
clean up and enable the corresponding doctests.
'kernel' crate:
- Add 'alloc' module with generic kernel allocator support and remove
the dependency on the Rust standard library 'alloc' and the extension
traits we used to provide fallible methods with flags.
Add the 'Allocator' trait and its implementations '{K,V,KV}malloc'.
Add the 'Box' type (a heap allocation for a single value of type 'T'
that is also generic over an allocator and considers the kernel's GFP
flags) and its shorthand aliases '{K,V,KV}Box'. Add 'ArrayLayout'
type. Add 'Vec' (a contiguous growable array type) and its shorthand
aliases '{K,V,KV}Vec', including iterator support.
For instance, now we may write code such as:
let mut v = KVec::new();
v.push(1, GFP_KERNEL)?;
assert_eq!(&v, &[1]);
Treewide, move as well old users to these new types.
- 'sync' module: add global lock support, including the
'GlobalLockBackend' trait; the 'Global{Lock,Guard,LockedBy}' types
and the 'global_lock!' macro. Add the 'Lock::try_lock' method.
- 'error' module: optimize 'Error' type to use 'NonZeroI32' and make
conversion functions public.
- 'page' module: add 'page_align' function.
- Add 'transmute' module with the existing 'FromBytes' and 'AsBytes'
traits.
- 'block::mq::request' module: improve rendered documentation.
- 'types' module: extend 'Opaque' type documentation and add simple
examples for the 'Either' types.
drm/panic:
- Clean up a series of Clippy warnings.
Documentation:
- Add coding guidelines for lints and the '#[expect]' feature.
- Add Ubuntu to the list of distributions in the Quick Start guide.
MAINTAINERS:
- Add Danilo Krummrich as maintainer of the new 'alloc' module.
And a few other small cleanups and fixes.
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Merge tag 'rust-6.13' of https://github.com/Rust-for-Linux/linux
Pull rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Enable a series of lints, including safety-related ones, e.g. the
compiler will now warn about missing safety comments, as well as
unnecessary ones. How safety documentation is organized is a
frequent source of review comments, thus having the compiler guide
new developers on where they are expected (and where not) is very
nice.
- Start using '#[expect]': an interesting feature in Rust (stabilized
in 1.81.0) that makes the compiler warn if an expected warning was
_not_ emitted. This is useful to avoid forgetting cleaning up
locally ignored diagnostics ('#[allow]'s).
- Introduce '.clippy.toml' configuration file for Clippy, the Rust
linter, which will allow us to tweak its behaviour. For instance,
our first use cases are declaring a disallowed macro and, more
importantly, enabling the checking of private items.
- Lints-related fixes and cleanups related to the items above.
- Migrate from 'receiver_trait' to 'arbitrary_self_types': to get the
kernel into stable Rust, one of the major pieces of the puzzle is
the support to write custom types that can be used as 'self', i.e.
as receivers, since the kernel needs to write types such as 'Arc'
that common userspace Rust would not. 'arbitrary_self_types' has
been accepted to become stable, and this is one of the steps
required to get there.
- Remove usage of the 'new_uninit' unstable feature.
- Use custom C FFI types. Includes a new 'ffi' crate to contain our
custom mapping, instead of using the standard library 'core::ffi'
one. The actual remapping will be introduced in a later cycle.
- Map '__kernel_{size_t,ssize_t,ptrdiff_t}' to 'usize'/'isize'
instead of 32/64-bit integers.
- Fix 'size_t' in bindgen generated prototypes of C builtins.
- Warn on bindgen < 0.69.5 and libclang >= 19.1 due to a double issue
in the projects, which we managed to trigger with the upcoming
tracepoint support. It includes a build test since some
distributions backported the fix (e.g. Debian -- thanks!). All
major distributions we list should be now OK except Ubuntu non-LTS.
'macros' crate:
- Adapt the build system to be able run the doctests there too; and
clean up and enable the corresponding doctests.
'kernel' crate:
- Add 'alloc' module with generic kernel allocator support and remove
the dependency on the Rust standard library 'alloc' and the
extension traits we used to provide fallible methods with flags.
Add the 'Allocator' trait and its implementations '{K,V,KV}malloc'.
Add the 'Box' type (a heap allocation for a single value of type
'T' that is also generic over an allocator and considers the
kernel's GFP flags) and its shorthand aliases '{K,V,KV}Box'. Add
'ArrayLayout' type. Add 'Vec' (a contiguous growable array type)
and its shorthand aliases '{K,V,KV}Vec', including iterator
support.
For instance, now we may write code such as:
let mut v = KVec::new();
v.push(1, GFP_KERNEL)?;
assert_eq!(&v, &[1]);
Treewide, move as well old users to these new types.
- 'sync' module: add global lock support, including the
'GlobalLockBackend' trait; the 'Global{Lock,Guard,LockedBy}' types
and the 'global_lock!' macro. Add the 'Lock::try_lock' method.
- 'error' module: optimize 'Error' type to use 'NonZeroI32' and make
conversion functions public.
- 'page' module: add 'page_align' function.
- Add 'transmute' module with the existing 'FromBytes' and 'AsBytes'
traits.
- 'block::mq::request' module: improve rendered documentation.
- 'types' module: extend 'Opaque' type documentation and add simple
examples for the 'Either' types.
drm/panic:
- Clean up a series of Clippy warnings.
Documentation:
- Add coding guidelines for lints and the '#[expect]' feature.
- Add Ubuntu to the list of distributions in the Quick Start guide.
MAINTAINERS:
- Add Danilo Krummrich as maintainer of the new 'alloc' module.
And a few other small cleanups and fixes"
* tag 'rust-6.13' of https://github.com/Rust-for-Linux/linux: (82 commits)
rust: alloc: Fix `ArrayLayout` allocations
docs: rust: remove spurious item in `expect` list
rust: allow `clippy::needless_lifetimes`
rust: warn on bindgen < 0.69.5 and libclang >= 19.1
rust: use custom FFI integer types
rust: map `__kernel_size_t` and friends also to usize/isize
rust: fix size_t in bindgen prototypes of C builtins
rust: sync: add global lock support
rust: macros: enable the rest of the tests
rust: macros: enable paste! use from macro_rules!
rust: enable macros::module! tests
rust: kbuild: expand rusttest target for macros
rust: types: extend `Opaque` documentation
rust: block: fix formatting of `kernel::block::mq::request` module
rust: macros: fix documentation of the paste! macro
rust: kernel: fix THIS_MODULE header path in ThisModule doc comment
rust: page: add Rust version of PAGE_ALIGN
rust: helpers: remove unnecessary header includes
rust: exports: improve grammar in commentary
drm/panic: allow verbose version check
...
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Merge tag 'vfs-6.13.rust.pid_namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull pid_namespace rust bindings from Christian Brauner:
"This contains my Rust bindings for pid namespaces needed for various
rust drivers. Here's a description of the basic C semantics and how
they are mapped to Rust.
The pid namespace of a task doesn't ever change once the task is
alive. A unshare(CLONE_NEWPID) or setns(fd_pidns/pidfd, CLONE_NEWPID)
will not have an effect on the calling task's pid namespace. It will
only effect the pid namespace of children created by the calling task.
This invariant guarantees that after having acquired a reference to a
task's pid namespace it will remain unchanged.
When a task has exited and been reaped release_task() will be called.
This will set the pid namespace of the task to NULL. So retrieving the
pid namespace of a task that is dead will return NULL. Note, that
neither holding the RCU lock nor holding a reference count to the task
will prevent release_task() from being called.
In order to retrieve the pid namespace of a task the
task_active_pid_ns() function can be used. There are two cases to
consider:
(1) retrieving the pid namespace of the current task
(2) retrieving the pid namespace of a non-current task
From system call context retrieving the pid namespace for case (1) is
always safe and requires neither RCU locking nor a reference count to
be held. Retrieving the pid namespace after release_task() for current
will return NULL but no codepath like that is exposed to Rust.
Retrieving the pid namespace from system call context for (2) requires
RCU protection. Accessing a pid namespace outside of RCU protection
requires a reference count that must've been acquired while holding
the RCU lock. Note that accessing a non-current task means NULL can be
returned as the non-current task could have already passed through
release_task().
To retrieve (1) the current_pid_ns!() macro should be used. It ensures
that the returned pid namespace cannot outlive the calling scope. The
associated current_pid_ns() function should not be called directly as
it could be abused to created an unbounded lifetime for the pid
namespace. The current_pid_ns!() macro allows Rust to handle the
common case of accessing current's pid namespace without RCU
protection and without having to acquire a reference count.
For (2) the task_get_pid_ns() method must be used. This will always
acquire a reference on the pid namespace and will return an Option to
force the caller to explicitly handle the case where pid namespace is
None. Something that tends to be forgotten when doing the equivalent
operation in C.
Missing RCU primitives make it difficult to perform operations that
are otherwise safe without holding a reference count as long as RCU
protection is guaranteed. But it is not important currently. But we do
want it in the future.
Note that for (2) the required RCU protection around calling
task_active_pid_ns() synchronizes against putting the last reference
of the associated struct pid of task->thread_pid. The struct pid
stored in that field is used to retrieve the pid namespace of the
caller. When release_task() is called task->thread_pid will be NULLed
and put_pid() on said struct pid will be delayed in free_pid() via
call_rcu() allowing everyone with an RCU protected access to the
struct pid acquired from task->thread_pid to finish"
* tag 'vfs-6.13.rust.pid_namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
rust: add PidNamespace
- Allow Rust code to have trace events
Trace events is a popular way to debug what is happening inside the kernel
or just to find out what is happening. Rust code is being added to the
Linux kernel but it currently does not support the tracing infrastructure.
Add support of trace events inside Rust code.
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Merge tag 'trace-rust-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull rust trace event support from Steven Rostedt:
"Allow Rust code to have trace events
Trace events is a popular way to debug what is happening inside the
kernel or just to find out what is happening. Rust code is being added
to the Linux kernel but it currently does not support the tracing
infrastructure. Add support of trace events inside Rust code"
* tag 'trace-rust-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
rust: jump_label: skip formatting generated file
jump_label: rust: pass a mut ptr to `static_key_count`
samples: rust: fix `rust_print` build making it a combined module
rust: add arch_static_branch
jump_label: adjust inline asm to be consistent
rust: samples: add tracepoint to Rust sample
rust: add tracepoint support
rust: add static_branch_unlikely for static_key_false
Add just enough support for static key so that we can use it from
tracepoints. Tracepoints rely on `static_branch_unlikely` with a `struct
static_key_false`, so we add the same functionality to Rust.
This patch only provides a generic implementation without code patching
(matching the one used when CONFIG_JUMP_LABEL is disabled). Later
patches add support for inline asm implementations that use runtime
patching.
When CONFIG_JUMP_LABEL is unset, `static_key_count` is a static inline
function, so a Rust helper is defined for `static_key_count` in this
case. If Rust is compiled with LTO, this call should get inlined. The
helper can be eliminated once we have the necessary inline asm to make
atomic operations from Rust.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " <bjorn3_gh@protonmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anup Patel <apatel@ventanamicro.com>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Conor Dooley <conor.dooley@microchip.com>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tianrui Zhao <zhaotianrui@loongson.cn>
Link: https://lore.kernel.org/20241030-tracepoint-v12-1-eec7f0f8ad22@google.com
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous
allocator, typically used for larger objects, (much) larger than page
size.
All memory allocations made with `Vmalloc` end up in `vrealloc()`.
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/20241004154149.93856-9-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The lifetime of `PidNamespace` is bound to `Task` and `struct pid`.
The `PidNamespace` of a `Task` doesn't ever change once the `Task` is
alive. A `unshare(CLONE_NEWPID)` or `setns(fd_pidns/pidfd, CLONE_NEWPID)`
will not have an effect on the calling `Task`'s pid namespace. It will
only effect the pid namespace of children created by the calling `Task`.
This invariant guarantees that after having acquired a reference to a
`Task`'s pid namespace it will remain unchanged.
When a task has exited and been reaped `release_task()` will be called.
This will set the `PidNamespace` of the task to `NULL`. So retrieving
the `PidNamespace` of a task that is dead will return `NULL`. Note, that
neither holding the RCU lock nor holding a referencing count to the
`Task` will prevent `release_task()` being called.
In order to retrieve the `PidNamespace` of a `Task` the
`task_active_pid_ns()` function can be used. There are two cases to
consider:
(1) retrieving the `PidNamespace` of the `current` task (2) retrieving
the `PidNamespace` of a non-`current` task
From system call context retrieving the `PidNamespace` for case (1) is
always safe and requires neither RCU locking nor a reference count to be
held. Retrieving the `PidNamespace` after `release_task()` for current
will return `NULL` but no codepath like that is exposed to Rust.
Retrieving the `PidNamespace` from system call context for (2) requires
RCU protection. Accessing `PidNamespace` outside of RCU protection
requires a reference count that must've been acquired while holding the
RCU lock. Note that accessing a non-`current` task means `NULL` can be
returned as the non-`current` task could have already passed through
`release_task()`.
To retrieve (1) the `current_pid_ns!()` macro should be used which
ensure that the returned `PidNamespace` cannot outlive the calling
scope. The associated `current_pid_ns()` function should not be called
directly as it could be abused to created an unbounded lifetime for
`PidNamespace`. The `current_pid_ns!()` macro allows Rust to handle the
common case of accessing `current`'s `PidNamespace` without RCU
protection and without having to acquire a reference count.
For (2) the `task_get_pid_ns()` method must be used. This will always
acquire a reference on `PidNamespace` and will return an `Option` to
force the caller to explicitly handle the case where `PidNamespace` is
`None`, something that tends to be forgotten when doing the equivalent
operation in `C`. Missing RCU primitives make it difficult to perform
operations that are otherwise safe without holding a reference count as
long as RCU protection is guaranteed. But it is not important currently.
But we do want it in the future.
Note for (2) the required RCU protection around calling
`task_active_pid_ns()` synchronizes against putting the last reference
of the associated `struct pid` of `task->thread_pid`. The `struct pid`
stored in that field is used to retrieve the `PidNamespace` of the
caller. When `release_task()` is called `task->thread_pid` will be
`NULL`ed and `put_pid()` on said `struct pid` will be delayed in
`free_pid()` via `call_rcu()` allowing everyone with an RCU protected
access to the `struct pid` acquired from `task->thread_pid` to finish.
Link: https://lore.kernel.org/r/20241002-brauner-rust-pid_namespace-v5-1-a90e70d44fde@kernel.org
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add an abstraction for viewing the string representation of a security
context.
This is needed by Rust Binder because it has a feature where a process
can view the string representation of the security context for incoming
transactions. The process can use that to authenticate incoming
transactions, and since the feature is provided by the kernel, the
process can trust that the security context is legitimate.
This abstraction makes the following assumptions about the C side:
* When a call to `security_secid_to_secctx` is successful, it returns a
pointer and length. The pointer references a byte string and is valid
for reading for that many bytes.
* The string may be referenced until `security_release_secctx` is
called.
* If CONFIG_SECURITY is set, then the three methods mentioned in
rust/helpers are available without a helper. (That is, they are not a
#define or `static inline`.)
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915-alice-file-v10-5-88484f7a3dcf@google.com
Acked-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add a wrapper around `struct cred` called `Credential`, and provide
functionality to get the `Credential` associated with a `File`.
Rust Binder must check the credentials of processes when they attempt to
perform various operations, and these checks usually take a
`&Credential` as parameter. The security_binder_set_context_mgr function
would be one example. This patch is necessary to access these security_*
methods from Rust.
This Rust abstraction makes the following assumptions about the C side:
* `struct cred` is refcounted with `get_cred`/`put_cred`.
* It's okay to transfer a `struct cred` across threads, that is, you do
not need to call `put_cred` on the same thread as where you called
`get_cred`.
* The `euid` field of a `struct cred` never changes after
initialization.
* The `f_cred` field of a `struct file` never changes after
initialization.
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915-alice-file-v10-4-88484f7a3dcf@google.com
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This abstraction makes it possible to manipulate the open files for a
process. The new `File` struct wraps the C `struct file`. When accessing
it using the smart pointer `ARef<File>`, the pointer will own a
reference count to the file. When accessing it as `&File`, then the
reference does not own a refcount, but the borrow checker will ensure
that the reference count does not hit zero while the `&File` is live.
Since this is intended to manipulate the open files of a process, we
introduce an `fget` constructor that corresponds to the C `fget`
method. In future patches, it will become possible to create a new fd in
a process and bind it to a `File`. Rust Binder will use these to send
fds from one process to another.
We also provide a method for accessing the file's flags. Rust Binder
will use this to access the flags of the Binder fd to check whether the
non-blocking flag is set, which affects what the Binder ioctl does.
This introduces a struct for the EBADF error type, rather than just
using the Error type directly. This has two advantages:
* `File::fget` returns a `Result<ARef<File>, BadFdError>`, which the
compiler will represent as a single pointer, with null being an error.
This is possible because the compiler understands that `BadFdError`
has only one possible value, and it also understands that the
`ARef<File>` smart pointer is guaranteed non-null.
* Additionally, we promise to users of the method that the method can
only fail with EBADF, which means that they can rely on this promise
without having to inspect its implementation.
That said, there are also two disadvantages:
* Defining additional error types involves boilerplate.
* The question mark operator will only utilize the `From` trait once,
which prevents you from using the question mark operator on
`BadFdError` in methods that return some third error type that the
kernel `Error` is convertible into. (However, it works fine in methods
that return `Error`.)
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915-alice-file-v10-3-88484f7a3dcf@google.com
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The rust rbtree exposes a map-like interface over keys and values,
backed by the kernel red-black tree implementation. Values can be
inserted, deleted, and retrieved from a `RBTree` by key.
This base abstraction is used by binder to store key/value
pairs and perform lookups, for example the patch
"[PATCH RFC 03/20] rust_binder: add threading support"
in the binder RFC [1].
Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-3-08ba9197f637@google.com/ [1]
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Matt Gilbride <mattgilbride@google.com>
Link: https://lore.kernel.org/r/20240822-b4-rbtree-v12-1-014561758a57@google.com
[ Updated link to docs.kernel.org. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This removes the need to explicitly export all symbols.
Generate helper exports similarly to what's currently done for Rust
crates. These helpers are exclusively called from within Rust code and
therefore can be treated similar as other Rust symbols.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240817165302.3852499-1-gary@garyguo.net
[ Fixed dependency path, reworded slightly, edited comment a bit and
rebased on top of the changes made when applying Andreas' patch
(e.g. no `README.md` anymore, so moved the edits). - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This patch splits up the rust helpers C file. When rebasing patch sets on
upstream linux, merge conflicts in helpers.c is common and time consuming
[1]. Thus, split the file so that each kernel component can live in a
separate file.
This patch lists helper files explicitly and thus conflicts in the file
list is still likely. However, they should be more simple to resolve than
the conflicts usually seen in helpers.c.
[ Removed `README.md` and undeleted the original comment since now,
in v3 of the series, we have a `helpers.c` again; which also allows
us to keep the "Sorted alphabetically" line and makes the diff easier.
In addition, updated the Documentation/ mentions of the file, reworded
title and removed blank lines at the end of `page.c`. - Miguel ]
Link: https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/Splitting.20up.20helpers.2Ec/near/426694012 [1]
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240815103016.2771842-1-nmi@metaspace.dk
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Viresh Kumar
Linus Torvalds
Rafael J. Wysocki
Dave Airlie
Alice Ryhl
Tamir Duberstein
Asahi Lina
Danilo Krummrich
FUJITA Tomonori
Mitchell Levy
Wedson Almeida Filho
Christian Brauner
Gary Guo
Andreas Hindborg