Commit Graph

12 Commits

Author SHA1 Message Date
Linus Torvalds
4793dae01f Merge tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Fix NULL pointer dereference in debugfs_create_str()
   - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str()
   - Fix soundwire debugfs NULL pointer dereference from uninitialized
     firmware_file

  device property:
   - Make fwnode flags modifications thread safe; widen the field to
     unsigned long and use set_bit() / clear_bit() based accessors
   - Document how to check for the property presence

  devres:
   - Separate struct devres_node from its "subclasses" (struct devres,
     struct devres_group); give struct devres_node its own release and
     free callbacks for per-type dispatch
   - Introduce struct devres_action for devres actions, avoiding the
     ARCH_DMA_MINALIGN alignment overhead of struct devres
   - Export struct devres_node and its init/add/remove/dbginfo
     primitives for use by Rust Devres<T>
   - Fix missing node debug info in devm_krealloc()
   - Use guard(spinlock_irqsave) where applicable; consolidate unlock
     paths in devres_release_group()

  driver_override:
   - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the
     generic driver_override infrastructure, replacing per-bus
     driver_override strings, sysfs attributes, and match logic; fixes a
     potential UAF from unsynchronized access to driver_override in bus
     match() callbacks
   - Simplify __device_set_driver_override() logic

  kernfs:
   - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs file
     and directory removal
   - Add corresponding selftests for memcg

  platform:
   - Allow attaching software nodes when creating platform devices via a
     new 'swnode' field in struct platform_device_info
   - Add kerneldoc for struct platform_device_info

  software node:
   - Move software node initialization from postcore_initcall() to
     driver_init(), making it available early in the boot process
   - Move kernel_kobj initialization (ksysfs_init) earlier to support
     the above
   - Remove software_node_exit(); dead code in a built-in unit

  SoC:
   - Introduce of_machine_read_compatible() and of_machine_read_model()
     OF helpers and export soc_attr_read_machine() to replace direct
     accesses to of_root from SoC drivers; also enables
     CONFIG_COMPILE_TEST coverage for these drivers

  sysfs:
   - Constify attribute group array pointers to
     'const struct attribute_group *const *' in sysfs functions,
     device_add_groups() / device_remove_groups(), and struct class

  Rust:
   - Devres:
      - Embed struct devres_node directly in Devres<T> instead of going
        through devm_add_action(), avoiding the extra allocation and the
        unnecessary ARCH_DMA_MINALIGN alignment

   - I/O:
      - Turn IoCapable from a marker trait into a functional trait
        carrying the raw I/O accessor implementation (io_read /
        io_write), providing working defaults for the per-type Io
        methods
      - Add RelaxedMmio wrapper type, making relaxed accessors usable in
        code generic over the Io trait
      - Remove overloaded per-type Io methods and per-backend macros
        from Mmio and PCI ConfigSpace

   - I/O (Register):
      - Add IoLoc trait and generic read/write/update methods to the Io
        trait, making I/O operations parameterizable by typed locations
      - Add register! macro for defining hardware register types with
        typed bitfield accessors backed by Bounded values; supports
        direct, relative, and array register addressing
      - Add write_reg() / try_write_reg() and LocatedRegister trait
      - Update PCI sample driver to demonstrate the register! macro

         Example:

         ```
             register! {
                 /// UART control register.
                 CTRL(u32) @ 0x18 {
                     /// Receiver enable.
                     19:19   rx_enable => bool;
                     /// Parity configuration.
                     14:13   parity ?=> Parity;
                 }

                 /// FIFO watermark and counter register.
                 WATER(u32) @ 0x2c {
                     /// Number of datawords in the receive FIFO.
                     26:24   rx_count;
                     /// RX interrupt threshold.
                     17:16   rx_water;
                 }
             }

             impl WATER {
                 fn rx_above_watermark(&self) -> bool {
                     self.rx_count() > self.rx_water()
                 }
             }

             fn init(bar: &pci::Bar<BAR0_SIZE>) {
                 let water = WATER::zeroed()
                     .with_const_rx_water::<1>(); // > 3 would not compile
                 bar.write_reg(water);

                 let ctrl = CTRL::zeroed()
                     .with_parity(Parity::Even)
                     .with_rx_enable(true);
                 bar.write_reg(ctrl);
             }

             fn handle_rx(bar: &pci::Bar<BAR0_SIZE>) {
                 if bar.read(WATER).rx_above_watermark() {
                     // drain the FIFO
                 }
             }

             fn set_parity(bar: &pci::Bar<BAR0_SIZE>, parity: Parity) {
                 bar.update(CTRL, |r| r.with_parity(parity));
             }
         ```

   - IRQ:
      - Move 'static bounds from where clauses to trait declarations for
        IRQ handler traits

   - Misc:
      - Enable the generic_arg_infer Rust feature
      - Extend Bounded with shift operations, single-bit bool
        conversion, and const get()

  Misc:
   - Make deferred_probe_timeout default a Kconfig option
   - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM
     callbacks when no bus type PM ops are set
   - Add conditional guard support for device_lock()
   - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry
   - Fix kernel-doc warnings in base.h
   - Fix stale reference to memory_block_add_nid() in documentation"

* tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (67 commits)
  bus: fsl-mc: use generic driver_override infrastructure
  s390/ap: use generic driver_override infrastructure
  s390/cio: use generic driver_override infrastructure
  vdpa: use generic driver_override infrastructure
  platform/wmi: use generic driver_override infrastructure
  PCI: use generic driver_override infrastructure
  driver core: make software nodes available earlier
  software node: remove software_node_exit()
  kernel: ksysfs: initialize kernel_kobj earlier
  MAINTAINERS: add ksysfs.c to the DRIVER CORE entry
  drivers/base/memory: fix stale reference to memory_block_add_nid()
  device property: Document how to check for the property presence
  soundwire: debugfs: initialize firmware_file to empty string
  debugfs: fix placement of EXPORT_SYMBOL_GPL for debugfs_create_str()
  debugfs: check for NULL pointer in debugfs_create_str()
  driver core: Make deferred_probe_timeout default a Kconfig option
  driver core: simplify __device_set_driver_override() clearing logic
  driver core: auxiliary bus: Drop auxiliary_dev_pm_ops
  device property: Make modifications of fwnode "flags" thread safe
  rust: devres: embed struct devres_node directly
  ...
2026-04-13 19:03:11 -07:00
Gary Guo
560a7a9b92 rust: add const_assert! macro
The macro is a more powerful version of `static_assert!` for use inside
function contexts. This is powered by inline consts, so enable the feature
for old compiler versions that does not have it stably.

While it is possible already to write `const { assert!(...) }`, this
provides a short hand that is more uniform with other assertions. It also
formats nicer with rustfmt where it will not be formatted into multiple
lines.

Two users that would route via the Rust tree are converted.

Reviewed-by: Yury Norov <ynorov@nvidia.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260319121653.2975748-3-gary@kernel.org
[ Rebased. Fixed period typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-03-30 02:03:49 +02:00
Alexandre Courbot
7836ec76ec rust: num: make Bounded::get const
There is a need to access the inner value of a `Bounded` in const
context, notably for bitfields and registers. Remove the invariant check
of `Bounded::get`, which allows us to make it const.

Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260314-register-v9-4-86805b2f7e9d@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-03-17 20:04:11 +01:00
Alexandre Courbot
164f8634bf rust: num: add into_bool method to Bounded
Single-bit numbers are typically treated as booleans. There is an
`Into<bool>` implementation for those, but invoking it from contexts
that lack type expectations is not always convenient.

Add an `into_bool` method as a simpler shortcut.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260314-register-v9-3-86805b2f7e9d@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-03-17 20:04:11 +01:00
Alexandre Courbot
c59a2d14cd rust: num: add shr and shl methods to Bounded
Shifting a `Bounded` left or right changes the number of bits required
to represent the value. Add methods that perform the shift and return a
`Bounded` with the appropriately adjusted bit width.

These methods are particularly useful for bitfield extraction.

Suggested-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Yury Norov <ynorov@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260314-register-v9-2-86805b2f7e9d@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-03-17 20:04:11 +01:00
Shivam Kalra
5016cae970 rust: num: bounded: clean __new documentation and comments
Following commit 3a1ec424dd ("rust: num: bounded: mark __new as
unsafe"), remove the redundant paragraph in the documentation of __new now
that the Safety section explicitly covers the requirement.

Additionally, add an INVARIANT comment inside the function body where
the Bounded instance is actually constructed to document that the type
invariant is upheld.

Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/rust-for-linux/CANiq72mUCUh72BWP4eD1PTDpwdb1ML+Xgfom-Ys6thJooqQPwQ@mail.gmail.com/
Signed-off-by: Shivam Kalra <shivamklr@cock.li>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260123132132.53854-1-shivamklr@cock.li
[ Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-01-26 02:53:16 +01:00
Alexandre Courbot
2af6ad09fc rust: num: bounded: add missing comment for always inlined function
This code is always inlined to avoid a build error if the error path of
`build_assert` cannot be optimized out. Add a comment justifying the
`#[inline(always)]` property to avoid it being taken away by mistake.

Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251208-io-build-assert-v3-7-98aded02c1ea@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-01-18 20:40:12 +01:00
Hsiu Che Yu
3a1ec424dd rust: num: bounded: mark __new as unsafe
The `Bounded::__new()` constructor relies on the caller to ensure the
value can be represented within N bits. Failing to uphold this
requirement breaks the type invariant. Mark it as unsafe and document
this requirement in a Safety section to make the contract explicit.

Update all call sites to use unsafe blocks and change their comments
from `INVARIANT:` to `SAFETY:`, as they are now justifying unsafe
operations rather than establishing type invariants.

Fixes: 01e345e82e ("rust: num: add Bounded integer wrapping type")
Link: https://lore.kernel.org/all/aS1qC_ol2XEpZ44b@google.com/
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://github.com/Rust-for-Linux/linux/issues/1211
Signed-off-by: Hsiu Che Yu <yu.whisper.personal@gmail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251204033849.23480-1-yu.whisper.personal@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-01-06 21:01:47 +01:00
Nakamura Shuta
f6b8d4b7e5 rust: num: fix typos in Bounded documentation
Fix several typos and grammatical errors in the Bounded type documentation:
- "less significant bits" -> "least significant bits"
- "with in" -> "within"
- "withheld" -> "upheld"
- "//  This" -> "// This" (double space)
- "doesn't fits" -> "doesn't fit" (2 occurrences)

Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://github.com/Rust-for-Linux/linux/issues/1210
Signed-off-by: Nakamura Shuta <nakamura.shuta@gmail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Yury Norov (NVIDIA) <yury.norov@nvidia.com>
Fixes: 01e345e82e ("rust: num: add Bounded integer wrapping type")
Link: https://patch.msgid.link/20251204024336.246587-1-nakamura.shuta@gmail.com
[ Removed Link tag due to duplicated URL. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-01-04 23:51:35 +01:00
Alexandre Courbot
841f31d298 rust: num: bounded: rename try_into_bitint to try_into_bounded
This is a remnant from when `Bounded` was called `BitInt` which I didn't
rename. Fix this.

Fixes: 01e345e82e ("rust: num: add Bounded integer wrapping type")
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251124-bounded_fix-v1-1-d8e34e1c727f@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-11-24 16:38:23 +01:00
Alexandre Courbot
bc197e24a3 rust: num: bounded: Always inline fits_within and from_expr
`from_expr` relies on `build_assert` to infer that the passed expression
fits the type's boundaries at build time. That inference can only be
successful its code (and that of `fits_within`, which performs the
check) is inlined, as a dedicated function would need to work with a
variable and cannot verify that property.

While inlining happens as expected in most cases, it is not guaranteed.
In particular, kernel options that optimize for size like
`CONFIG_CC_OPTIMIZE_FOR_SIZE` can result in `from_expr` not being
inlined.

Add `#[inline(always)]` attributes to both `fits_within` and `from_expr`
to make the compiler inline these functions more aggressively, as it
does not make sense to use them non-inlined anyway.

[ For reference, the errors look like:

    ld.lld: error: undefined symbol: rust_build_error
    >>> referenced by build_assert.rs:83 (rust/kernel/build_assert.rs:83)
    >>>               rust/doctests_kernel_generated.o:(<kernel::num::bounded::Bounded<u8, 1>>::from_expr) in archive vmlinux.a

      - Miguel ]

Fixes: 01e345e82e ("rust: num: add Bounded integer wrapping type")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202511210055.RUsFNku1-lkp@intel.com/
Suggested-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251122-bounded_ints_fix-v1-1-1e07589d4955@nvidia.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-11-23 22:49:55 +01:00
Alexandre Courbot
01e345e82e rust: num: add Bounded integer wrapping type
Add the `Bounded` integer wrapper type, which restricts the number of
bits allowed to represent of value.

This is useful to e.g. enforce guarantees when working with bitfields
that have an arbitrary number of bits.

Alongside this type, provide many `From` and `TryFrom` implementations
are to reduce friction when using with regular integer types. Proxy
implementations of common integer operations are also provided.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251108-bounded_ints-v4-2-c9342ac7ebd1@nvidia.com
[ Added intra-doc link. Fixed a few other nits. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-11-19 00:22:24 +01:00