Commit graph

113 commits

Author SHA1 Message Date
Linus Torvalds
ec7714e494 Rust changes for v6.16
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
  ...
2025-06-04 21:18:37 -07:00
Linus Torvalds
00c010e130 - The 11 patch series "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.
 
 - 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
  ...
2025-05-31 15:44:16 -07:00
Rafael J. Wysocki
25961ae6c8 Merge branch 'pm-cpufreq'
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
2025-05-30 20:11:09 +02:00
Tamir Duberstein
b20fbbc08a rust: check type of $ptr in container_of!
Add a compile-time check that `*$ptr` is of the type of `$type->$($f)*`.
Rename those placeholders for clarity.

Given the incorrect usage:

> diff --git a/rust/kernel/rbtree.rs b/rust/kernel/rbtree.rs
> index 8d978c896747..6a7089149878 100644
> --- a/rust/kernel/rbtree.rs
> +++ b/rust/kernel/rbtree.rs
> @@ -329,7 +329,7 @@ fn raw_entry(&mut self, key: &K) -> RawEntry<'_, K, V> {
>          while !(*child_field_of_parent).is_null() {
>              let curr = *child_field_of_parent;
>              // SAFETY: All links fields we create are in a `Node<K, V>`.
> -            let node = unsafe { container_of!(curr, Node<K, V>, links) };
> +            let node = unsafe { container_of!(curr, Node<K, V>, key) };
>
>              // SAFETY: `node` is a non-null node so it is valid by the type invariants.
>              match key.cmp(unsafe { &(*node).key }) {

this patch produces the compilation error:

> error[E0308]: mismatched types
>    --> rust/kernel/lib.rs:220:45
>     |
> 220 |         $crate::assert_same_type(field_ptr, (&raw const (*container_ptr).$($fields)*).cast_mut());
>     |         ------------------------ ---------  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `*mut rb_node`, found `*mut K`
>     |         |                        |
>     |         |                        expected all arguments to be this `*mut bindings::rb_node` type because they need to match the type of this parameter
>     |         arguments to this function are incorrect
>     |
>    ::: rust/kernel/rbtree.rs:270:6
>     |
> 270 | impl<K, V> RBTree<K, V>
>     |      - found this type parameter
> ...
> 332 |             let node = unsafe { container_of!(curr, Node<K, V>, key) };
>     |                                 ------------------------------------ in this macro invocation
>     |
>     = note: expected raw pointer `*mut bindings::rb_node`
>                found raw pointer `*mut K`
> note: function defined here
>    --> rust/kernel/lib.rs:227:8
>     |
> 227 | pub fn assert_same_type<T>(_: T, _: T) {}
>     |        ^^^^^^^^^^^^^^^^ -  ----  ---- this parameter needs to match the `*mut bindings::rb_node` type of parameter #1
>     |                         |  |
>     |                         |  parameter #2 needs to match the `*mut bindings::rb_node` type of this parameter
>     |                         parameter #1 and parameter #2 both reference this parameter `T`
>     = note: this error originates in the macro `container_of` (in Nightly builds, run with -Z macro-backtrace for more info)

[ We decided to go with a variation of v1 [1] that became v4, since it
  seems like the obvious approach, the error messages seem good enough
  and the debug performance should be fine, given the kernel is always
  built with -O2.

  In the future, we may want to make the helper non-hidden, with
  proper documentation, for others to use.

  [1] https://lore.kernel.org/rust-for-linux/CANiq72kQWNfSV0KK6qs6oJt+aGdgY=hXg=wJcmK3zYcokY1LNw@mail.gmail.com/

    - Miguel ]

Suggested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/all/CAH5fLgh6gmqGBhPMi2SKn7mCmMWfOSiS0WP5wBuGPYh9ZTAiww@mail.gmail.com/
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250529-b4-container-of-type-check-v4-1-bf3a7ad73cec@gmail.com
[ Added intra-doc link. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-29 23:16:38 +02:00
Tamir Duberstein
74d6a606c2 rust: retain pointer mut-ness in container_of!
Avoid casting the input pointer to `*const _`, allowing the output
pointer to be `*mut` if the input is `*mut`. This allows a number of
`*const` to `*mut` conversions to be removed at the cost of slightly
worse ergonomics when the macro is used with a reference rather than a
pointer; the only example of this was in the macro's own doctest.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250409-container-of-mutness-v1-1-64f472b94534@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-28 18:54:09 +02:00
Linus Torvalds
b08494a8f7 drm for 6.16-rc1
new drivers:
 - bring in the asahi uapi header standalone
 - nova-drm: stub driver
 
 rust dependencies (for nova-core):
 - auxiliary
   - bus abstractions
   - driver registration
   - sample driver
 - devres changes from driver-core
 - revocable changes
 
 core:
 - add Apple fourcc modifiers
 - add virtio capset definitions
 - extend EXPORT_SYNC_FILE for timeline syncobjs
 - convert to devm_platform_ioremap_resource
 - refactor shmem helper page pinning
 - DP powerup/down link helpers
 - remove disgusting turds
 - extended %p4cc in vsprintf.c to support fourcc prints
 - change vsprintf %p4cn to %p4chR, remove %p4cn
 - Add drm_file_err function
 - IN_FORMATS_ASYNC property
 - move sitronix from tiny to their own subdir
 
 rust:
 - add drm core infrastructure rust abstractions
   (device/driver, ioctl, file, gem)
 
 dma-buf:
 - adjust sg handling to not cache map on attach
 - allow setting dma-device for import
 - Add a helper to sort and deduplicate dma_fence arrays
 
 docs:
 - updated drm scheduler docs
 - fbdev todo update
 - fb rendering
 - actual brightness
 
 ttm:
 - fix delayed destroy resv object
 
 bridge:
 - add kunit tests
 - convert tc358775 to atomic
 - convert drivers to devm_drm_bridge_alloc
 - convert rk3066_hdmi to bridge driver
 
 scheduler:
 - add kunit tests
 
 panel:
 - refcount panels to improve lifetime handling
 - Powertip PH128800T004-ZZA01
 - NLT NL13676BC25-03F, Tianma TM070JDHG34-00
 - Himax HX8279/HX8279-D DDIC
 - Visionox G2647FB105
 - Sitronix ST7571
 - ZOTAC rotation quirk
 
 vkms:
 - allow attaching more displays
 
 i915:
 - xe3lpd display updates
 - vrr refactor
 - intel_display struct conversions
 - xe2hpd memory type identification
 - add link rate/count to i915_display_info
 - cleanup VGA plane handling
 - refactor HDCP GSC
 - fix SLPC wait boosting reference counting
 - add 20ms delay to engine reset
 - fix fence release on early probe errors
 
 xe:
 - SRIOV updates
 - BMG PCI ID update
 - support separate firmware for each GT
 - SVM fix, prelim SVM multi-device work
 - export fan speed
 - temp disable d3cold on BMG
 - backup VRAM in PM notifier instead of suspend/freeze
 - update xe_ttm_access_memory to use GPU for non-visible access
 - fix guc_info debugfs for VFs
 - use copy_from_user instead of __copy_from_user
 - append PCIe gen5 limitations to xe_firmware document
 
 amdgpu:
 - DSC cleanup
 - DC Scaling updates
 - Fused I2C-over-AUX updates
 - DMUB updates
 - Use drm_file_err in amdgpu
 - Enforce isolation updates
 - Use new dma_fence helpers
 - USERQ fixes
 - Documentation updates
 - SR-IOV updates
 - RAS updates
 - PSP 12 cleanups
 - GC 9.5 updates
 - SMU 13.x updates
 - VCN / JPEG SR-IOV updates
 
 amdkfd:
 - Update error messages for SDMA
 - Userptr updates
 - XNACK fixes
 
 radeon:
 - CIK doorbell cleanup
 
 nouveau:
 - add support for NVIDIA r570 GSP firmware
 - enable Hopper/Blackwell support
 
 nova-core:
 - fix task list
 - register definition infrastructure
 - move firmware into own rust module
 - register auxiliary device for nova-drm
 
 nova-drm:
 - initial driver skeleton
 
 msm:
 - GPU:
   - ACD (adaptive clock distribution) for X1-85
   - drop fictional address_space_size
   - improve GMU HFI response time out robustness
   - fix crash when throttling during boot
 - DPU:
   - use single CTL path for flushing on DPU 5.x+
   - improve SSPP allocation code for better sharing
   - Enabled SmartDMA on SM8150, SC8180X, SC8280XP, SM8550
   - Added SAR2130P support
   - Disabled DSC support on MSM8937, MSM8917, MSM8953, SDM660
 - DP:
   - switch to new audio helpers
   - better LTTPR handling
 - DSI:
   - Added support for SA8775P
   - Added SAR2130P support
 - HDMI:
   - Switched to use new helpers for ACR data
   - Fixed old standing issue of HPD not working in some cases
 
 amdxdna:
 - add dma-buf support
 - allow empty command submits
 
 renesas:
 - add dma-buf support
 - add zpos, alpha, blend support
 
 panthor:
 - fail properly for NO_MMAP bos
 - add SET_LABEL ioctl
 - debugfs BO dumping support
 
 imagination:
 - update DT bindings
 - support TI AM68 GPU
 
 hibmc:
 - improve interrupt handling and HPD support
 
 virtio:
 - add panic handler support
 
 rockchip:
 - add RK3588 support
 - add DP AUX bus panel support
 
 ivpu:
 - add heartbeat based hangcheck
 
 mediatek:
 - prepares support for MT8195/99 HDMIv2/DDCv2
 
 anx7625:
 - improve HPD
 
 tegra:
 - speed up firmware loading
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Merge tag 'drm-next-2025-05-28' of https://gitlab.freedesktop.org/drm/kernel

Pull drm updates from Dave Airlie:
 "As part of building up nova-core/nova-drm pieces we've brought in some
  rust abstractions through this tree, aux bus being the main one, with
  devres changes also in the driver-core tree. Along with the drm core
  abstractions and enough nova-core/nova-drm to use them. This is still
  all stub work under construction, to build the nova driver upstream.

  The other big NVIDIA related one is nouveau adds support for
  Hopper/Blackwell GPUs, this required a new GSP firmware update to
  570.144, and a bunch of rework in order to support multiple fw
  interfaces.

  There is also the introduction of an asahi uapi header file as a
  precursor to getting the real driver in later, but to unblock
  userspace mesa packages while the driver is trapped behind rust
  enablement.

  Otherwise it's the usual mixture of stuff all over, amdgpu, i915/xe,
  and msm being the main ones, and some changes to vsprintf.

  new drivers:
   - bring in the asahi uapi header standalone
   - nova-drm: stub driver

  rust dependencies (for nova-core):
   - auxiliary
       - bus abstractions
       - driver registration
       - sample driver
   - devres changes from driver-core
   - revocable changes

  core:
   - add Apple fourcc modifiers
   - add virtio capset definitions
   - extend EXPORT_SYNC_FILE for timeline syncobjs
   - convert to devm_platform_ioremap_resource
   - refactor shmem helper page pinning
   - DP powerup/down link helpers
   - extended %p4cc in vsprintf.c to support fourcc prints
   - change vsprintf %p4cn to %p4chR, remove %p4cn
   - Add drm_file_err function
   - IN_FORMATS_ASYNC property
   - move sitronix from tiny to their own subdir

  rust:
   - add drm core infrastructure rust abstractions
     (device/driver, ioctl, file, gem)

  dma-buf:
   - adjust sg handling to not cache map on attach
   - allow setting dma-device for import
   - Add a helper to sort and deduplicate dma_fence arrays

  docs:
   - updated drm scheduler docs
   - fbdev todo update
   - fb rendering
   - actual brightness

  ttm:
   - fix delayed destroy resv object

  bridge:
   - add kunit tests
   - convert tc358775 to atomic
   - convert drivers to devm_drm_bridge_alloc
   - convert rk3066_hdmi to bridge driver

  scheduler:
   - add kunit tests

  panel:
   - refcount panels to improve lifetime handling
   - Powertip PH128800T004-ZZA01
   - NLT NL13676BC25-03F, Tianma TM070JDHG34-00
   - Himax HX8279/HX8279-D DDIC
   - Visionox G2647FB105
   - Sitronix ST7571
   - ZOTAC rotation quirk

  vkms:
   - allow attaching more displays

  i915:
   - xe3lpd display updates
   - vrr refactor
   - intel_display struct conversions
   - xe2hpd memory type identification
   - add link rate/count to i915_display_info
   - cleanup VGA plane handling
   - refactor HDCP GSC
   - fix SLPC wait boosting reference counting
   - add 20ms delay to engine reset
   - fix fence release on early probe errors

  xe:
   - SRIOV updates
   - BMG PCI ID update
   - support separate firmware for each GT
   - SVM fix, prelim SVM multi-device work
   - export fan speed
   - temp disable d3cold on BMG
   - backup VRAM in PM notifier instead of suspend/freeze
   - update xe_ttm_access_memory to use GPU for non-visible access
   - fix guc_info debugfs for VFs
   - use copy_from_user instead of __copy_from_user
   - append PCIe gen5 limitations to xe_firmware document

  amdgpu:
   - DSC cleanup
   - DC Scaling updates
   - Fused I2C-over-AUX updates
   - DMUB updates
   - Use drm_file_err in amdgpu
   - Enforce isolation updates
   - Use new dma_fence helpers
   - USERQ fixes
   - Documentation updates
   - SR-IOV updates
   - RAS updates
   - PSP 12 cleanups
   - GC 9.5 updates
   - SMU 13.x updates
   - VCN / JPEG SR-IOV updates

  amdkfd:
   - Update error messages for SDMA
   - Userptr updates
   - XNACK fixes

  radeon:
   - CIK doorbell cleanup

  nouveau:
   - add support for NVIDIA r570 GSP firmware
   - enable Hopper/Blackwell support

  nova-core:
   - fix task list
   - register definition infrastructure
   - move firmware into own rust module
   - register auxiliary device for nova-drm

  nova-drm:
   - initial driver skeleton

  msm:
   - GPU:
       - ACD (adaptive clock distribution) for X1-85
       - drop fictional address_space_size
       - improve GMU HFI response time out robustness
       - fix crash when throttling during boot
   - DPU:
       - use single CTL path for flushing on DPU 5.x+
       - improve SSPP allocation code for better sharing
       - Enabled SmartDMA on SM8150, SC8180X, SC8280XP, SM8550
       - Added SAR2130P support
       - Disabled DSC support on MSM8937, MSM8917, MSM8953, SDM660
   - DP:
       - switch to new audio helpers
       - better LTTPR handling
   - DSI:
       - Added support for SA8775P
       - Added SAR2130P support
   - HDMI:
       - Switched to use new helpers for ACR data
       - Fixed old standing issue of HPD not working in some cases

  amdxdna:
   - add dma-buf support
   - allow empty command submits

  renesas:
   - add dma-buf support
   - add zpos, alpha, blend support

  panthor:
   - fail properly for NO_MMAP bos
   - add SET_LABEL ioctl
   - debugfs BO dumping support

  imagination:
   - update DT bindings
   - support TI AM68 GPU

  hibmc:
   - improve interrupt handling and HPD support

  virtio:
   - add panic handler support

  rockchip:
   - add RK3588 support
   - add DP AUX bus panel support

  ivpu:
   - add heartbeat based hangcheck

  mediatek:
   - prepares support for MT8195/99 HDMIv2/DDCv2

  anx7625:
   - improve HPD

  tegra:
   - speed up firmware loading

* tag 'drm-next-2025-05-28' of https://gitlab.freedesktop.org/drm/kernel: (1627 commits)
  drm/nouveau/tegra: Fix error pointer vs NULL return in nvkm_device_tegra_resource_addr()
  drm/xe: Default auto_link_downgrade status to false
  drm/xe/guc: Make creation of SLPC debugfs files conditional
  drm/i915/display: Add check for alloc_ordered_workqueue() and alloc_workqueue()
  drm/i915/dp_mst: Work around Thunderbolt sink disconnect after SINK_COUNT_ESI read
  drm/i915/ptl: Use everywhere the correct DDI port clock select mask
  drm/nouveau/kms: add support for GB20x
  drm/dp: add option to disable zero sized address only transactions.
  drm/nouveau: add support for GB20x
  drm/nouveau/gsp: add hal for fifo.chan.doorbell_handle
  drm/nouveau: add support for GB10x
  drm/nouveau/gf100-: track chan progress with non-WFI semaphore release
  drm/nouveau/nv50-: separate CHANNEL_GPFIFO handling out from CHANNEL_DMA
  drm/nouveau: add helper functions for allocating pinned/cpu-mapped bos
  drm/nouveau: add support for GH100
  drm/nouveau: improve handling of 64-bit BARs
  drm/nouveau/gv100-: switch to volta semaphore methods
  drm/nouveau/gsp: support deeper page tables in COPY_SERVER_RESERVED_PDES
  drm/nouveau/gsp: init client VMMs with NV0080_CTRL_DMA_SET_PAGE_DIRECTORY
  drm/nouveau/gsp: fetch level shift and PDE from BAR2 VMM
  ...
2025-05-28 09:46:39 -07:00
Viresh Kumar
2207856ff0 rust: cpufreq: Add initial abstractions for cpufreq framework
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>
2025-05-20 11:21:10 +05:30
Viresh Kumar
8f835497b3 rust: opp: Add initial abstractions for OPP framework
Introduce initial Rust abstractions for the Operating Performance Points
(OPP) framework. This includes bindings for `struct dev_pm_opp` and
`struct dev_pm_opp_data`, laying the groundwork for further OPP
integration.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-05-20 10:04:06 +05:30
Viresh Kumar
3accb57d56 rust: cpu: Add from_cpu()
This implements cpu::from_cpu(), which returns a reference to
Device for a CPU. The C struct is created at initialization time for
CPUs and is never freed and so ARef isn't returned from this function.

The new helper will be used by Rust based cpufreq drivers.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-05-20 10:04:06 +05:30
Viresh Kumar
d01d702056 rust: clk: Add initial abstractions
Add initial abstractions for the clk APIs. These provide the minimal
functionality needed for common use cases, making them straightforward
to introduce in the first iteration.

These will be used by Rust based cpufreq / OPP layers to begin with.

Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-05-19 12:55:40 +05:30
Viresh Kumar
8961b8cb30 rust: cpumask: Add initial abstractions
Add initial Rust abstractions for struct cpumask, covering a subset of
its APIs. Additional APIs can be added as needed.

These abstractions will be used in upcoming Rust support for cpufreq and
OPP frameworks.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
2025-05-19 12:55:40 +05:30
Miguel Ojeda
06ff274f25 Rust xarray API for v6.16
Introduce Rust support for the `xarray` data structure:
 
  - Add a rust abstraction for the `xarray` data structure. This abstraction
    allows rust code to leverage the `xarray` to store types that implement
    `ForeignOwnable`. This support is a dependency for memory backing feature of
    the rust null block driver, which is waiting to be merged.
 
  - Set up an entry in MAINTAINERS for the xarray rust support. Patches will go
    to the new rust xarray tree and then via the rust subsystem tree for now.
 
 `kernel` crate:
 
  - Allow `ForeignOwnable` to carry information about the pointed-to type. This
    helps asserting alignment requirements for the pointer passed to the foreign
    language.
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Merge tag 'rust-xarray-for-v6.16' of https://github.com/Rust-for-Linux/linux into rust-next

Pull XArray updates from Andreas Hindborg:
 "Introduce Rust support for the 'xarray' data structure:

   - Add a Rust abstraction for the 'xarray' data structure. This
     abstraction allows Rust code to leverage the 'xarray' to store
     types that implement 'ForeignOwnable'. This support is a dependency
     for memory backing feature of the Rust null block driver, which is
     waiting to be merged.

   - Set up an entry in MAINTAINERS for the XArray Rust support. Patches
     will go to the new Rust XArray tree and then via the Rust subsystem
     tree for now.

  'kernel' crate:

   - Allow 'ForeignOwnable' to carry information about the pointed-to
     type. This helps asserting alignment requirements for the pointer
     passed to the foreign language."

* tag 'rust-xarray-for-v6.16' of https://github.com/Rust-for-Linux/linux:
  MAINTAINERS: add entry for Rust XArray API
  rust: xarray: Add an abstraction for XArray
  rust: types: add `ForeignOwnable::PointedTo`
2025-05-18 20:36:56 +02:00
Andreas Hindborg
446cafc295 rust: configfs: introduce rust support for configfs
Add a Rust API for configfs, thus allowing Rust modules to use configfs for
configuration. Make the implementation a shim on top of the C configfs
implementation, allowing safe use of the C infrastructure from Rust.

Link: https://lore.kernel.org/r/20250508-configfs-v8-1-8ebde6180edc@kernel.org
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-05-12 11:05:07 +02:00
Alice Ryhl
5bb9ed6cdf mm: rust: add abstraction for struct mm_struct
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>
2025-05-11 17:48:24 -07:00
Miguel Ojeda
b9b701fce4 rust: clarify the language unstable features in use
We track the details of which Rust features we use at our usual "live
list" [1] (and its sub-lists), but in light of a discussion in the LWN
article [2], it would help to clarify it in the source code.

In particular, we are very close to rely only on stable Rust language-wise
-- essentially only two language features remain (including the `kernel`
crate).

Thus add some details in both the feature list of the `kernel` crate as
well as the list of allowed features.

This does not over every single feature, and there are quite a few
non-language features that we use too. To have the full picture, please
refer to [1].

Link: https://github.com/Rust-for-Linux/linux/issues/2 [1]
Link: https://lwn.net/Articles/1015409/ [2]
Suggested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250327211302.286313-1-ojeda@kernel.org
[ Improved comments with suggestions from the list. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-12 00:20:25 +02:00
Tamir Duberstein
210b81578e rust: xarray: Add an abstraction for XArray
`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>
2025-05-01 11:37:59 +02:00
Asahi Lina
9a69570682 rust: drm: ioctl: Add DRM ioctl abstraction
DRM drivers need to be able to declare which driver-specific ioctls they
support. Add an abstraction implementing the required types and a helper
macro to generate the ioctl definition inside the DRM driver.

Note that this macro is not usable until further bits of the abstraction
are in place (but it will not fail to compile on its own, if not called).

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/20250410235546.43736-3-dakr@kernel.org
[ MISC fixes
    * wrap raw_data in Opaque to avoid UB when creating a reference
    * fix IOCTL sample declaration
    * fix safety comment of IOCTL argument
    * original source archive: https://archive.is/LqHDQ

  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-04-24 13:50:05 +02:00
Danilo Krummrich
ce735e73dd rust: auxiliary: add auxiliary device / driver abstractions
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>
2025-04-19 10:54:25 +02:00
Linus Torvalds
4e82c87058 Rust changes for v6.15
Toolchain and infrastructure:
 
  - Extract the 'pin-init' API from the 'kernel' crate and make it into
    a standalone crate.
 
    In order to do this, the contents are rearranged so that they can
    easily be kept in sync with the version maintained out-of-tree that
    other projects have started to use too (or plan to, like QEMU).
 
    This will reduce the maintenance burden for Benno, who will now have
    his own sub-tree, and will simplify future expected changes like the
    move to use 'syn' to simplify the implementation.
 
  - Add '#[test]'-like support based on KUnit.
 
    We already had doctests support based on KUnit, which takes the
    examples in our Rust documentation and runs them under KUnit.
 
    Now, we are adding the beginning of the support for "normal" tests,
    similar to those the '#[test]' tests in userspace Rust. For instance:
 
        #[kunit_tests(my_suite)]
        mod tests {
            #[test]
            fn my_test() {
                assert_eq!(1 + 1, 2);
            }
        }
 
    Unlike with doctests, the 'assert*!'s do not map to the KUnit
    assertion APIs yet.
 
  - Check Rust signatures at compile time for functions called from C by
    name.
 
    In particular, introduce a new '#[export]' macro that can be placed
    in the Rust function definition. It will ensure that the function
    declaration on the C side matches the signature on the Rust function:
 
        #[export]
        pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize {
            // ...
        }
 
    The macro essentially forces the compiler to compare the types of
    the actual Rust function and the 'bindgen'-processed C signature.
 
    These cases are rare so far. In the future, we may consider
    introducing another tool, 'cbindgen', to generate C headers
    automatically. Even then, having these functions explicitly marked
    may be a good idea anyway.
 
  - Enable the 'raw_ref_op' Rust feature: it is already stable, and
    allows us to use the new '&raw' syntax, avoiding a couple macros.
    After everyone has migrated, we will disallow the macros.
 
  - Pass the correct target to 'bindgen' on Usermode Linux.
 
  - Fix 'rusttest' build in macOS.
 
 'kernel' crate:
 
  - New 'hrtimer' module: add support for setting up intrusive timers
    without allocating when starting the timer. Add support for
    'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer types
    for use with timer callbacks. Add support for setting clock source
    and timer mode.
 
  - New 'dma' module: add a simple DMA coherent allocator abstraction and
    a test sample driver.
 
  - 'list' module: make the linked list 'Cursor' point between elements,
    rather than at an element, which is more convenient to us and allows
    for cursors to empty lists; and document it with examples of how to
    perform common operations with the provided methods.
 
  - 'str' module: implement a few traits for 'BStr' as well as the
    'strip_prefix()' method.
 
  - 'sync' module: add 'Arc::as_ptr'.
 
  - 'alloc' module: add 'Box::into_pin'.
 
  - 'error' module: extend the 'Result' documentation, including a few
    examples on different ways of handling errors, a warning about using
    methods that may panic, and links to external documentation.
 
 'macros' crate:
 
   - 'module' macro: add the 'authors' key to support multiple authors.
     The original key will be kept until everyone has migrated.
 
 Documentation:
 
  - Add error handling sections.
 
 MAINTAINERS:
 
  - Add Danilo Krummrich as reviewer of the Rust "subsystem".
 
  - Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has
    its own sub-tree.
 
  - Add sub-tree for 'RUST [ALLOC]'.
 
  - Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with Abdiel
    Janulgue as primary maintainer. It will go through the sub-tree of
    the 'RUST [ALLOC]' entry.
 
  - Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as
    maintainer. It has its own sub-tree.
 
 And a few other cleanups and improvements.
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Merge tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Extract the 'pin-init' API from the 'kernel' crate and make it into
     a standalone crate.

     In order to do this, the contents are rearranged so that they can
     easily be kept in sync with the version maintained out-of-tree that
     other projects have started to use too (or plan to, like QEMU).

     This will reduce the maintenance burden for Benno, who will now
     have his own sub-tree, and will simplify future expected changes
     like the move to use 'syn' to simplify the implementation.

   - Add '#[test]'-like support based on KUnit.

     We already had doctests support based on KUnit, which takes the
     examples in our Rust documentation and runs them under KUnit.

     Now, we are adding the beginning of the support for "normal" tests,
     similar to those the '#[test]' tests in userspace Rust. For
     instance:

         #[kunit_tests(my_suite)]
         mod tests {
             #[test]
             fn my_test() {
                 assert_eq!(1 + 1, 2);
             }
         }

     Unlike with doctests, the 'assert*!'s do not map to the KUnit
     assertion APIs yet.

   - Check Rust signatures at compile time for functions called from C
     by name.

     In particular, introduce a new '#[export]' macro that can be placed
     in the Rust function definition. It will ensure that the function
     declaration on the C side matches the signature on the Rust
     function:

         #[export]
         pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize {
             // ...
         }

     The macro essentially forces the compiler to compare the types of
     the actual Rust function and the 'bindgen'-processed C signature.

     These cases are rare so far. In the future, we may consider
     introducing another tool, 'cbindgen', to generate C headers
     automatically. Even then, having these functions explicitly marked
     may be a good idea anyway.

   - Enable the 'raw_ref_op' Rust feature: it is already stable, and
     allows us to use the new '&raw' syntax, avoiding a couple macros.
     After everyone has migrated, we will disallow the macros.

   - Pass the correct target to 'bindgen' on Usermode Linux.

   - Fix 'rusttest' build in macOS.

  'kernel' crate:

   - New 'hrtimer' module: add support for setting up intrusive timers
     without allocating when starting the timer. Add support for
     'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer
     types for use with timer callbacks. Add support for setting clock
     source and timer mode.

   - New 'dma' module: add a simple DMA coherent allocator abstraction
     and a test sample driver.

   - 'list' module: make the linked list 'Cursor' point between
     elements, rather than at an element, which is more convenient to us
     and allows for cursors to empty lists; and document it with
     examples of how to perform common operations with the provided
     methods.

   - 'str' module: implement a few traits for 'BStr' as well as the
     'strip_prefix()' method.

   - 'sync' module: add 'Arc::as_ptr'.

   - 'alloc' module: add 'Box::into_pin'.

   - 'error' module: extend the 'Result' documentation, including a few
     examples on different ways of handling errors, a warning about
     using methods that may panic, and links to external documentation.

  'macros' crate:

   - 'module' macro: add the 'authors' key to support multiple authors.
     The original key will be kept until everyone has migrated.

  Documentation:

   - Add error handling sections.

  MAINTAINERS:

   - Add Danilo Krummrich as reviewer of the Rust "subsystem".

   - Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has
     its own sub-tree.

   - Add sub-tree for 'RUST [ALLOC]'.

   - Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with
     Abdiel Janulgue as primary maintainer. It will go through the
     sub-tree of the 'RUST [ALLOC]' entry.

   - Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as
     maintainer. It has its own sub-tree.

  And a few other cleanups and improvements"

* tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (71 commits)
  rust: dma: add `Send` implementation for `CoherentAllocation`
  rust: macros: fix `make rusttest` build on macOS
  rust: block: refactor to use `&raw mut`
  rust: enable `raw_ref_op` feature
  rust: uaccess: name the correct function
  rust: rbtree: fix comments referring to Box instead of KBox
  rust: hrtimer: add maintainer entry
  rust: hrtimer: add clocksource selection through `ClockId`
  rust: hrtimer: add `HrTimerMode`
  rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
  rust: alloc: add `Box::into_pin`
  rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
  rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
  rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
  rust: hrtimer: add `UnsafeHrTimerPointer`
  rust: hrtimer: allow timer restart from timer handler
  rust: str: implement `strip_prefix` for `BStr`
  rust: str: implement `AsRef<BStr>` for `[u8]` and `BStr`
  rust: str: implement `Index` for `BStr`
  rust: str: implement `PartialEq` for `BStr`
  ...
2025-03-30 17:03:26 -07:00
Antonio Hickey
e1dfaa33fd rust: enable raw_ref_op feature
Since Rust 1.82.0 the `raw_ref_op` feature is stable [1].

By enabling this feature we can use `&raw const place` and
`&raw mut place` instead of using `addr_of!(place)` and
`addr_of_mut!(place)` macros.

Allowing us to reduce macro complexity, and improve consistency
with existing reference syntax as `&raw const`, `&raw mut` are
similar to `&`, `&mut` making it fit more naturally with other
existing code.

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://github.com/Rust-for-Linux/linux/issues/1148
Link: https://blog.rust-lang.org/2024/10/17/Rust-1.82.0.html#native-syntax-for-creating-a-raw-pointer [1]
Signed-off-by: Antonio Hickey <contact@antoniohickey.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250320020740.1631171-2-contact@antoniohickey.com
[ Removed dashed line change as discussed. Added Link to the explanation
  of the feature in the Rust 1.82.0 release blog post. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-23 19:56:45 +01:00
Abdiel Janulgue
ad2907b4e3 rust: add dma coherent allocator abstraction
Add a simple dma coherent allocator rust abstraction. Based on
Andreas Hindborg's dma abstractions from the rnvme driver, which
was also based on earlier work by Wedson Almeida Filho.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250317185345.2608976-3-abdiel.janulgue@gmail.com
Nacked-by: Christoph Hellwig <hch@lst.de>
[ Removed period. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-20 21:44:46 +01:00
Benno Lossin
dbd5058ba6 rust: make pin-init its own crate
Rename relative paths inside of the crate to still refer to the same
items, also rename paths inside of the kernel crate and adjust the build
system to build the crate.

[ Remove the `expect` (and thus the `lint_reasons` feature) since
  the tree now uses `quote!` from `rust/macros/export.rs`. Remove the
  `TokenStream` import removal, since it is now used as well.

  In addition, temporarily (i.e. just for this commit) use an `--extern
  force:alloc` to prevent an unknown `new_uninit` error in the `rustdoc`
  target. For context, please see a similar case in:

      https://lore.kernel.org/lkml/20240422090644.525520-1-ojeda@kernel.org/

  And adjusted the message above. - Miguel ]

Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:19 +01:00
Benno Lossin
86f7dacade rust: add extensions to the pin-init crate and move relevant documentation there
In preparation of splitting off the pin-init crate from the kernel
crate, move all kernel-specific documentation from pin-init back into
the kernel crate.

Also include an example from the user-space version [1] adapted to the
kernel.

The new `init.rs` file will also be populated by kernel-specific
extensions to the pin-init crate by the next commits.

Link: c1417c64c7/src/lib.rs (L161) [1]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-4-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Benno Lossin
fbf8fb328d rust: move pin-init API into its own directory
In preparation of splitting off the pin-init crate from the kernel
crate, move all pin-init API code (including proc-macros) into
`rust/pin-init`.

Moved modules have their import path adjusted via the `#[path = "..."]`
attribute. This allows the files to still be imported in the kernel
crate even though the files are in different directories.

Code that is moved out of files (but the file itself stays where it is)
is imported via the `include!` macro. This also allows the code to be
moved while still being part of the kernel crate.

Note that this commit moves the generics parsing code out of the GPL-2.0
file `rust/macros/helpers.rs` into the Apache-2.0 OR MIT file
`rust/pin_init/internal/src/helpers.rs`. I am the sole author of that
code and it already is available with that license at [1].
The same is true for the entry-points of the proc-macros `pin_data`,
`pinned_drop` and `derive_zeroable` in `rust/macros/lib.rs` that are
moved to `rust/pin_data/internal/src/lib.rs`. Although there are some
smaller patches that fix the doctests.

Link: https://github.com/Rust-for-Linux/pinned-init [1]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-3-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-16 21:59:18 +01:00
Miguel Ojeda
374908a15a rust: remove leftover mentions of the alloc crate
In commit 392e34b6bc ("kbuild: rust: remove the `alloc` crate and
`GlobalAlloc`") we stopped using the upstream `alloc` crate.

Thus remove a few leftover mentions treewide.

Cc: stable@vger.kernel.org # Also to 6.12.y after the `alloc` backport lands
Fixes: 392e34b6bc ("kbuild: rust: remove the `alloc` crate and `GlobalAlloc`")
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250303171030.1081134-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-03-05 23:55:56 +01:00
Lyude Paul
78418f300d rust/kernel: Add faux device bindings
This introduces a module for working with faux devices in rust, along with
adding sample code to show how the API is used. Unlike other types of
devices, we don't provide any hooks for device probe/removal - since these
are optional for the faux API and are unnecessary in rust.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Maíra Canal <mairacanal@riseup.net>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/2025021026-exert-accent-b4c6@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-13 16:58:58 +01:00
Linus Torvalds
2ab002c755 Driver core and debugfs updates
Here is the big set of driver core and debugfs updates for 6.14-rc1.
 It's coming late in the merge cycle as there are a number of merge
 conflicts with your tree now, and I wanted to make sure they were
 working properly.  To resolve them, look in linux-next, and I will send
 the "fixup" patch as a response to the pull request.
 
 Included in here is a bunch of driver core, PCI, OF, and platform rust
 bindings (all acked by the different subsystem maintainers), hence the
 merge conflict with the rust tree, and some driver core api updates to
 mark things as const, which will also require some fixups due to new
 stuff coming in through other trees in this merge window.
 
 There are also a bunch of debugfs updates from Al, and there is at least
 one user that does have a regression with these, but Al is working on
 tracking down the fix for it.  In my use (and everyone else's linux-next
 use), it does not seem like a big issue at the moment.
 
 Here's a short list of the things in here:
   - driver core bindings for PCI, platform, OF, and some i/o functions.
     We are almost at the "write a real driver in rust" stage now,
     depending on what you want to do.
   - misc device rust bindings and a sample driver to show how to use
     them
   - debugfs cleanups in the fs as well as the users of the fs api for
     places where drivers got it wrong or were unnecessarily doing things
     in complex ways.
   - driver core const work, making more of the api take const * for
     different parameters to make the rust bindings easier overall.
   - other small fixes and updates
 
 All of these have been in linux-next with all of the aforementioned
 merge conflicts, and the one debugfs issue, which looks to be resolved
 "soon".
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the big set of driver core and debugfs updates for 6.14-rc1.

  Included in here is a bunch of driver core, PCI, OF, and platform rust
  bindings (all acked by the different subsystem maintainers), hence the
  merge conflict with the rust tree, and some driver core api updates to
  mark things as const, which will also require some fixups due to new
  stuff coming in through other trees in this merge window.

  There are also a bunch of debugfs updates from Al, and there is at
  least one user that does have a regression with these, but Al is
  working on tracking down the fix for it. In my use (and everyone
  else's linux-next use), it does not seem like a big issue at the
  moment.

  Here's a short list of the things in here:

   - driver core rust bindings for PCI, platform, OF, and some i/o
     functions.

     We are almost at the "write a real driver in rust" stage now,
     depending on what you want to do.

   - misc device rust bindings and a sample driver to show how to use
     them

   - debugfs cleanups in the fs as well as the users of the fs api for
     places where drivers got it wrong or were unnecessarily doing
     things in complex ways.

   - driver core const work, making more of the api take const * for
     different parameters to make the rust bindings easier overall.

   - other small fixes and updates

  All of these have been in linux-next with all of the aforementioned
  merge conflicts, and the one debugfs issue, which looks to be resolved
  "soon""

* tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
  rust: device: Use as_char_ptr() to avoid explicit cast
  rust: device: Replace CString with CStr in property_present()
  devcoredump: Constify 'struct bin_attribute'
  devcoredump: Define 'struct bin_attribute' through macro
  rust: device: Add property_present()
  saner replacement for debugfs_rename()
  orangefs-debugfs: don't mess with ->d_name
  octeontx2: don't mess with ->d_parent or ->d_parent->d_name
  arm_scmi: don't mess with ->d_parent->d_name
  slub: don't mess with ->d_name
  sof-client-ipc-flood-test: don't mess with ->d_name
  qat: don't mess with ->d_name
  xhci: don't mess with ->d_iname
  mtu3: don't mess wiht ->d_iname
  greybus/camera - stop messing with ->d_iname
  mediatek: stop messing with ->d_iname
  netdevsim: don't embed file_operations into your structs
  b43legacy: make use of debugfs_get_aux()
  b43: stop embedding struct file_operations into their objects
  carl9170: stop embedding file_operations into their objects
  ...
2025-01-28 12:25:12 -08:00
Xiangfei Ding
47cb6bf786 rust: use derive(CoercePointee) on rustc >= 1.84.0
The `kernel` crate relies on both `coerce_unsized` and `dispatch_from_dyn`
unstable features.

Alice Ryhl has proposed [1] the introduction of the unstable macro
`SmartPointer` to reduce such dependence, along with a RFC patch [2].
Since Rust 1.81.0 this macro, later renamed to `CoercePointee` in
Rust 1.84.0 [3], has been fully implemented with the naming discussion
resolved.

This feature is now on track to stabilization in the language.
In order to do so, we shall start using this macro in the `kernel` crate
to prove the functionality and utility of the macro as the justification
of its stabilization.

This patch makes this switch in such a way that the crate remains
backward compatible with older Rust compiler versions,
via the new Kconfig option `RUSTC_HAS_COERCE_POINTEE`.

A minimal demonstration example is added to the
`samples/rust/rust_print_main.rs` module.

Link: https://rust-lang.github.io/rfcs/3621-derive-smart-pointer.html [1]
Link: https://lore.kernel.org/all/20240823-derive-smart-pointer-v1-1-53769cd37239@google.com/ [2]
Link: https://github.com/rust-lang/rust/pull/131284 [3]
Signed-off-by: Xiangfei Ding <dingxiangfei2009@gmail.com>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20241203205050.679106-2-dingxiangfei2009@gmail.com
[ Fixed version to 1.84. Renamed option to `RUSTC_HAS_COERCE_POINTEE`
  to match `CC_HAS_*` ones. Moved up new config option, closer to the
  `CC_HAS_*` ones. Simplified Kconfig line. Fixed typos and slightly
  reworded example and commit. Added Link to PR. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-01-13 23:45:30 +01:00
Miguel Ojeda
614724e780 rust: kernel: move build_error hidden function to prevent mistakes
Users were using the hidden exported `kernel::build_error` function
instead of the intended `kernel::build_error!` macro, e.g. see the
previous commit.

To force to use the macro, move it into the `build_assert` module,
thus making it a compilation error and avoiding a collision in the same
"namespace". Using the function now would require typing the module name
(which is hidden), not just a single character.

Now attempting to use the function will trigger this error with the
right suggestion by the compiler:

      error[E0423]: expected function, found macro `kernel::build_error`
      --> samples/rust/rust_minimal.rs:29:9
         |
      29 |         kernel::build_error();
         |         ^^^^^^^^^^^^^^^^^^^ not a function
         |
      help: use `!` to invoke the macro
         |
      29 |         kernel::build_error!();
         |                            +

An alternative would be using an alias, but it would be more complex
and moving it into the module seems right since it belongs there and
reduces the amount of code at the crate root.

Keep the `#[doc(hidden)]` inside `build_assert` in case the module is
not hidden in the future.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20241123222849.350287-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-01-10 00:19:09 +01:00
Danilo Krummrich
9b88018932 rust: io: move module entry to its correct location
The module entry of `io` falsely ended up in the "use" block instead of
the "mod" block, hence move it to its correct location.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250103164655.96590-3-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-07 11:31:45 +01:00
Danilo Krummrich
7e16820fe5 rust: pci: do not depend on CONFIG_PCI_MSI
The PCI abstractions do not actually depend on CONFIG_PCI_MSI; it also
breaks drivers that only depend on CONFIG_PCI, hence drop it.

While at it, move the module entry to its correct location.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501030744.4ucqC1cB-lkp@intel.com/
Fixes: 1bd8b6b2c5 ("rust: pci: add basic PCI device / driver abstractions")
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250103164655.96590-2-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-07 11:31:39 +01:00
Danilo Krummrich
683a63befc rust: platform: add basic platform device / driver abstractions
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>
2024-12-20 17:21:05 +01:00
Danilo Krummrich
bbe3b4d158 rust: of: add of::DeviceId abstraction
`of::DeviceId` is an abstraction around `struct of_device_id`.

This is used by subsequent patches, in particular the platform bus
abstractions, to create OF device ID tables.

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>
Tested-by: Fabien Parent <fabien.parent@linaro.org>
Link: https://lore.kernel.org/r/20241219170425.12036-13-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20 17:21:04 +01:00
Danilo Krummrich
1bd8b6b2c5 rust: pci: add basic PCI device / driver abstractions
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>
2024-12-20 17:19:26 +01:00
Danilo Krummrich
76c01ded72 rust: add devres abstraction
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>
2024-12-20 17:19:26 +01:00
Danilo Krummrich
ce30d94e68 rust: add io::{Io, IoRaw} base types
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>
2024-12-20 17:19:26 +01:00
Wedson Almeida Filho
0494d9c82b rust: add Revocable type
Revocable allows access to objects to be safely revoked at run time.

This is useful, for example, for resources allocated during device probe;
when the device is removed, the driver should stop accessing the device
resources even if another state is kept in memory due to existing
references (i.e., device context data is ref-counted and has a non-zero
refcount after removal of the device).

Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Danilo Krummrich <dakr@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/20241219170425.12036-7-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20 17:19:26 +01:00
Danilo Krummrich
9b90864bb4 rust: implement IdArray, IdTable and RawDeviceId
Most subsystems use some kind of ID to match devices and drivers. Hence,
we have to provide Rust drivers an abstraction to register an ID table
for the driver to match.

Generally, those IDs are subsystem specific and hence need to be
implemented by the corresponding subsystem. However, the `IdArray`,
`IdTable` and `RawDeviceId` types provide a generalized implementation
that makes the life of subsystems easier to do so.

Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Fabien Parent <fabien.parent@linaro.org>
Signed-off-by: Fabien Parent <fabien.parent@linaro.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Tested-by: Fabien Parent <fabien.parent@linaro.org>
Link: https://lore.kernel.org/r/20241219170425.12036-4-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20 17:19:25 +01:00
Danilo Krummrich
ea7e18289f rust: implement generic driver registration
Implement the generic `Registration` type and the `RegistrationOps`
trait.

The `Registration` structure is the common type that represents a driver
registration and is typically bound to the lifetime of a module. However,
it doesn't implement actual calls to the kernel's driver core to register
drivers itself.

Instead the `RegistrationOps` trait is provided to subsystems, which have
to implement `RegistrationOps::register` and
`RegistrationOps::unregister`. Subsystems have to provide an
implementation for both of those methods where the subsystem specific
variants to register / unregister a driver have to implemented.

For instance, the PCI subsystem would call __pci_register_driver() from
`RegistrationOps::register` and pci_unregister_driver() from
`DrvierOps::unregister`.

Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Tested-by: Fabien Parent <fabien.parent@linaro.org>
Link: https://lore.kernel.org/r/20241219170425.12036-3-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20 17:19:25 +01:00
Danilo Krummrich
a790265c7f rust: module: add trait ModuleMetadata
In order to access static metadata of a Rust kernel module, add the
`ModuleMetadata` trait.

In particular, this trait provides the name of a Rust kernel module as
specified by the `module!` macro.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Tested-by: Fabien Parent <fabien.parent@linaro.org>
Link: https://lore.kernel.org/r/20241219170425.12036-2-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-20 17:19:25 +01:00
Linus Torvalds
2eff01ee28 Char/Misc/IIO/Whatever driver subsystem updates for 6.13-rc1
Here is the "big and hairy" char/misc/iio and other small driver
 subsystem updates for 6.13-rc1.  Sorry for doing this at the end of the
 merge window, conference and holiday travel got in the way on my side
 (hence the 5am pull request emails...)
 
 Loads of things in here, and even a fun merge conflict!
   - rust misc driver bindings and other rust changes to make misc
     drivers actually possible.  I think this is the tipping point,
     expect to see way more rust drivers going forward now that these
     bindings are present.  Next merge window hopefully we will have pci
     and platform drivers working, which will fully enable almost all
     driver subsystems to start accepting (or at least getting) rust
     drivers.  This is the end result of a lot of work from a lot of
     people, congrats to all of them for getting this far, you've proved
     many of us wrong in the best way possible, working code :)
   - IIO driver updates, too many to list individually, that subsystem
     keeps growing and growing...
   - Interconnect driver updates
   - nvmem driver updates
   - pwm driver updates
   - platform_driver::remove() fixups, loads of them
   - counter driver updates
   - misc driver updates (keba?)
   - binder driver updates and fixes
   - loads of other small char/misc/etc driver updates and additions,
     full details in the shortlog.
 
 Note, there is a semi-hairy rust merge conflict when pulling this.  The
 resolution has been in linux-next for a while and can be seen here:
 	https://lore.kernel.org/all/20241111173459.2646d4af@canb.auug.org.au/
 
 All of these have been in linux-next for a while, with no other reported
 issues other than that merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc/IIO/whatever driver subsystem updates from Greg KH:
 "Here is the 'big and hairy' char/misc/iio and other small driver
  subsystem updates for 6.13-rc1.

  Loads of things in here, and even a fun merge conflict!

   - rust misc driver bindings and other rust changes to make misc
     drivers actually possible.

     I think this is the tipping point, expect to see way more rust
     drivers going forward now that these bindings are present. Next
     merge window hopefully we will have pci and platform drivers
     working, which will fully enable almost all driver subsystems to
     start accepting (or at least getting) rust drivers.

     This is the end result of a lot of work from a lot of people,
     congrats to all of them for getting this far, you've proved many of
     us wrong in the best way possible, working code :)

   - IIO driver updates, too many to list individually, that subsystem
     keeps growing and growing...

   - Interconnect driver updates

   - nvmem driver updates

   - pwm driver updates

   - platform_driver::remove() fixups, loads of them

   - counter driver updates

   - misc driver updates (keba?)

   - binder driver updates and fixes

   - loads of other small char/misc/etc driver updates and additions,
     full details in the shortlog.

  All of these have been in linux-next for a while, with no other
  reported issues other than that merge conflict"

* tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (401 commits)
  mei: vsc: Fix typo "maintstepping" -> "mainstepping"
  firmware: Switch back to struct platform_driver::remove()
  misc: isl29020: Fix the wrong format specifier
  scripts/tags.sh: Don't tag usages of DEFINE_MUTEX
  fpga: Switch back to struct platform_driver::remove()
  mei: vsc: Improve error logging in vsc_identify_silicon()
  mei: vsc: Do not re-enable interrupt from vsc_tp_reset()
  dt-bindings: spmi: qcom,x1e80100-spmi-pmic-arb: Add SAR2130P compatible
  dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8188
  spmi: pmic-arb: fix return path in for_each_available_child_of_node()
  iio: Move __private marking before struct element priv in struct iio_dev
  docs: iio: ad7380: add adaq4370-4 and adaq4380-4
  iio: adc: ad7380: add support for adaq4370-4 and adaq4380-4
  iio: adc: ad7380: use local dev variable to shorten long lines
  iio: adc: ad7380: fix oversampling formula
  dt-bindings: iio: adc: ad7380: add adaq4370-4 and adaq4380-4 compatible parts
  bus: mhi: host: pci_generic: Use pcim_iomap_region() to request and map MHI BAR
  bus: mhi: host: Switch trace_mhi_gen_tre fields to native endian
  misc: atmel-ssc: Use of_property_present() for non-boolean properties
  misc: keba: Add hardware dependency
  ...
2024-11-29 11:58:27 -08:00
Linus Torvalds
798bb342e0 Rust changes for v6.13
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
  ...
2024-11-26 14:00:26 -08:00
Linus Torvalds
9ad8d22f2f vfs-6.13.rust.pid_namespace
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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
2024-11-26 13:18:00 -08:00
Linus Torvalds
7f4f3b14e8 Add Rust support for trace events:
- 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
2024-11-25 15:44:29 -08:00
Gary Guo
d072acda48 rust: use custom FFI integer types
Currently FFI integer types are defined in libcore. This commit creates
the `ffi` crate and asks bindgen to use that crate for FFI integer types
instead of `core::ffi`.

This commit is preparatory and no type changes are made in this commit
yet.

Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-4-gary@garyguo.net
[ Added `rustdoc`, `rusttest` and KUnit tests support. Rebased on top of
  `rust-next` (e.g. migrated more `core::ffi` cases). Reworded crate
  docs slightly and formatted. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-11-10 23:58:00 +01:00
Wedson Almeida Filho
7f15c46a57 rust: introduce InPlaceModule
This allows modules to be initialised in-place in pinned memory, which
enables the usage of pinned types (e.g., mutexes, spinlocks, driver
registrations, etc.) in modules without any extra allocations.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20241022213221.2383-3-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05 05:33:41 +01:00
Alice Ryhl
169484ab66 rust: add arch_static_branch
To allow the Rust implementation of static_key_false to use runtime code
patching instead of the generic implementation, pull in the relevant
inline assembly from the jump_label.h header by running the C
preprocessor on a .rs.S file. Build rules are added for .rs.S files.

Since the relevant inline asm has been adjusted to export the inline asm
via the ARCH_STATIC_BRANCH_ASM macro in a consistent way, the Rust side
does not need architecture specific code to pull in the asm.

It is not possible to use the existing C implementation of
arch_static_branch via a Rust helper because it passes the argument
`key` to inline assembly as an 'i' parameter. Any attempt to add a C
helper for this function will fail to compile because the value of `key`
must be known at compile-time.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
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-v12-5-eec7f0f8ad22@google.com
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-11-04 16:21:45 -05:00
Alice Ryhl
ad37bcd965 rust: add tracepoint support
Make it possible to have Rust code call into tracepoints defined by C
code. It is still required that the tracepoint is declared in a C
header, and that this header is included in the input to bindgen.

Instead of calling __DO_TRACE directly, the exported rust_do_trace_
function calls an inline helper function. This is because the `cond`
argument does not exist at the callsite of DEFINE_RUST_DO_TRACE.

__DECLARE_TRACE always emits an inline static and an extern declaration
that is only used when CREATE_RUST_TRACE_POINTS is set. These should not
end up in the final binary so it is not a problem that they sometimes
are emitted without a user.

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-v12-2-eec7f0f8ad22@google.com
Reviewed-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-11-04 16:21:44 -05:00
Alice Ryhl
6e59bcc9c8 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>
2024-11-04 16:21:44 -05:00
Yutaro Ohno
8b55dc8610 rust: kernel: fix THIS_MODULE header path in ThisModule doc comment
The doc comment for `ThisModule` incorrectly states the C header file
for `THIS_MODULE` as `include/linux/export.h`, while the correct path is
`include/linux/init.h`. This is because `THIS_MODULE` was moved in
commit 5b20755b77 ("init: move THIS_MODULE from <linux/export.h> to
<linux/init.h>").

Update the doc comment for `ThisModule` to reflect the correct header
file path for `THIS_MODULE`.

Fixes: 5b20755b77 ("init: move THIS_MODULE from <linux/export.h> to <linux/init.h>")
Signed-off-by: Yutaro Ohno <yutaro.ono.418@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/ZxXDZwxWgoEiIYkj@ohnotp
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-10-21 20:35:53 +02:00