linux-stable.git/rust/kernel/prelude.rs, branch linux-7.0.y

Merge tag 'drm-next-2025-12-03' of https://gitlab.freedesktop.org/drm/kernel

2025-12-04T16:53:30+00:00

Pull drm updates from Dave Airlie:
 "There was a rather late merge of a new color pipeline feature, that
  some userspace projects are blocked on, and has seen a lot of work in
  amdgpu. This should have seen some time in -next. There is additional
  support for this for Intel, that if it arrives in the next day or two
  I'll pass it on in another pull request and you can decide if you want
  to take it.

  Highlights:
   - Arm Ethos NPU accelerator driver
   - new DRM color pipeline support
   - amdgpu will now run discrete SI/CIK cards instead of radeon, which
     enables vulkan support in userspace
   - msm gets gen8 gpu support
   - initial Xe3P support in xe

  Full detail summary:

  New driver:
   - Arm Ethos-U65/U85 accel driver

  Core:
   - support the drm color pipeline in vkms/amdgfx
   - add support for drm colorop pipeline
   - add COLOR PIPELINE plane property
   - add DRM_CLIENT_CAP_PLANE_COLOR_PIPELINE
   - throttle dirty worker with vblank
   - use drm_for_each_bridge_in_chain_scoped in drm's bridge code
   - Ensure drm_client_modeset tests are enabled in UML
   - add simulated vblank interrupt - use in drivers
   - dumb buffer sizing helper
   - move freeing of drm client memory to driver
   - crtc sharpness strength property
   - stop using system_wq in scheduler/drivers
   - support emergency restore in drm-client

  Rust:
   - make slice::as_flattened usable on all supported rustc
   - add FromBytes::from_bytes_prefix() method
   - remove redundant device ptr from Rust GEM object
   - Change how AlwaysRefCounted is implemented for GEM objects

  gpuvm:
   - Add deferred vm_bo cleanup to GPUVM (for rust)

  atomic:
   - cleanup and improve state handling interfaces

  buddy:
   - optimize block management

  dma-buf:
   - heaps: Create heap per CMA reserved location
   - improve userspace documentation

  dp:
   - add POST_LT_ADJ_REQ training sequence
   - DPCD dSC quirk for synaptics panamera devices
   - helpers to query branch DSC max throughput

  ttm:
   - Rename ttm_bo_put to ttm_bo_fini
   - allow page protection flags on risc-v
   - rework pipelined eviction fence handling

  amdgpu:
   - enable amdgpu by default for SI/CI dGPUs
   - enable DC by default on SI
   - refactor CIK/SI enablement
   - add ABM KMS property
   - Re-enable DM idle optimizations
   - DC Analog encoders support
   - Powerplay fixes for fiji/iceland
   - Enable DC on bonaire by default
   - HMM cleanup
   - Add new RAS framework
   - DML2.1 updates
   - YCbCr420 fixes
   - DC FP fixes
   - DMUB fixes
   - LTTPR fixes
   - DTBCLK fixes
   - DMU cursor offload handling
   - Userq validation improvements
   - Unify shutdown callback handling
   - Suspend improvements
   - Power limit code cleanup
   - SR-IOV fixes
   - AUX backlight fixes
   - DCN 3.5 fixes
   - HDMI compliance fixes
   - DCN 4.0.1 cursor updates
   - DCN interrupt fix
   - DC KMS full update improvements
   - Add additional HDCP traces
   - DCN 3.2 fixes
   - DP MST fixes
   - Add support for new SR-IOV mailbox interface
   - UQ reset support
   - HDP flush rework
   - VCE1 support

  amdkfd:
   - HMM cleanups
   - Relax checks on save area overallocations
   - Fix GPU mappings after prefetch

  radeon:
   - refactor CIK/SI enablement

  xe:
   - Initial Xe3P support
   - panic support on VRAM for display
   - fix stolen size check
   - Loosen used tracking restriction
   - New SR-IOV debugfs structure and debugfs updates
   - Hide the GPU madvise flag behind a VM_BIND flag
   - Always expose VRAM provisioning data on discrete GPUs
   - Allow VRAM mappings for userptr when used with SVM
   - Allow pinning of p2p dma-buf
   - Use per-tile debugfs where appropriate
   - Add documentation for Execution Queues
   - PF improvements
   - VF migration recovery redesign work
   - User / Kernel VRAM partitioning
   - Update Tile-based messages
   - Allow configfs to disable specific GT types
   - VF provisioning and migration improvements
   - use SVM range helpers in PT layer
   - Initial CRI support
   - access VF registers using dedicated MMIO view
   - limit number of jobs per exec queue
   - add sriov_admin sysfs tree
   - more crescent island specific support
   - debugfs residency counter
   - SRIOV migration work
   - runtime registers for GFX 35

  i915:
   - add initial Xe3p_LPD display version 35 support
   - Enable LNL+ content adaptive sharpness filter
   - Use optimized VRR guardband
   - Enable Xe3p LT PHY
   - enable FBC support for Xe3p_LPD display
   - add display 30.02 firmware support
   - refactor SKL+ watermark latency setup
   - refactor fbdev handling
   - call i915/xe runtime PM via function pointers
   - refactor i915/xe stolen memory/display interfaces
   - use display version instead of gfx version in display code
   - extend i915_display_info with Type-C port details
   - lots of display cleanups/refactorings
   - set O_LARGEFILE in __create_shmem
   - skuip guc communication warning on reset
   - fix time conversions
   - defeature DRRS on LNL+
   - refactor intel_frontbuffer split between i915/xe/display
   - convert inteL_rom interfaces to struct drm_device
   - unify display register polling interfaces
   - aovid lock inversion when pinning to GGTT on CHV/BXT+VTD

  panel:
   - Add KD116N3730A08/A12, chromebook mt8189
   - JT101TM023, LQ079L1SX01,
   - GLD070WX3-SL01 MIPI DSI
   - Samsung LTL106AL0, Samsung LTL106AL01
   - Raystar RFF500F-AWH-DNN
   - Winstar WF70A8SYJHLNGA
   - Wanchanglong w552946aaa
   - Samsung SOFEF00
   - Lenovo X13s panel
   - ilitek-ili9881c - add rpi 5" support
   - visionx-rm69299 - add backlight support
   - edp - support AUI B116XAN02.0

  bridge:
   - improve ref counting
   - ti-sn65dsi86 - add support for DP mode with HPD
   - synopsis: support CEC, init timer with correct freq
   - ASL CS5263 DP-to-HDMI bridge support

  nova-core:
   - introduce bitfield! macro
   - introduce safe integer converters
   - GSP inits to fully booted state on Ampere
   - Use more future-proof register for GPU identification

  nova-drm:
   - select NOVA_CORE
   - 64-bit only

  nouveau:
   - improve reclocking on tegra 186+
   - add large page and compression support

  msm:
   - GPU:
      - Gen8 support: A840 (Kaanapali) and X2-85 (Glymur)
      - A612 support
   - MDSS:
      - Added support for Glymur and QCS8300 platforms
   - DPU:
      - Enabled Quad-Pipe support, unlocking higher resolutions support
      - Added support for Glymur platform
      - Documented DPU on QCS8300 platform as supported
   - DisplayPort:
      - Added support for Glymur platform
      - Added support lame remapping inside DP block
      - Documented DisplayPort controller on QCS8300 and SM6150/QCS615
        as supported

  tegra:
   - NVJPG driver

  panfrost:
   - display JM contexts over debugfs
   - export JM contexts to userspace
   - improve error and job handling

  panthor:
   - support custom ASN_HASH for mt8196
   - support mali-G1 GPU
   - flush shmem write before mapping buffers uncached
   - make timeout per-queue instead of per-job

  mediatek:
   - MT8195/88 HDMIv2/DDCv2 support

  rockchip:
   - dsi: add support for RK3368

  amdxdna:
   - enhance runtime PM
   - last hardware error reading uapi
   - support firmware debug output
   - add resource and telemetry data uapi
   - preemption support

  imx:
   - add driver for HDMI TX Parallel audio interface

  ivpu:
   - add support for user-managed preemption buffer
   - add userptr support
   - update JSM firware API to 3.33.0
   - add better alloc/free warnings
   - fix page fault in unbind all bos
   - rework bind/unbind of imported buffers
   - enable MCA ECC signalling
   - split fw runtime and global memory buffers
   - add fdinfo memory statistics

  tidss:
   - convert to drm logging
   - logging cleanup

  ast:
   - refactor generation init paths
   - add per chip generation detect_tx_chip
   - set quirks for each chip model

  atmel-hlcdc:
   - set LCDC_ATTRE register in plane disable
   - set correct values for plane scaler

  solomon:
   - use drm helper for get_modes and move_valid

  sitronix:
   - fix output position when clearing screens

  qaic:
   - support dma-buf exports
   - support new firmware's READ_DATA implementation
   - sahara AIC200 image table update
   - add sysfs support
   - add coredump support
   - add uevents support
   - PM support

  sun4i:
   - layer refactors to decouple plane from output
   - improve DE33 support

  vc4:
   - switch to generic CEC helpers

  komeda:
   - use drm_ logging functions

  vkms:
   - configfs support for display configuration

  vgem:
   - fix fence timer deadlock

  etnaviv:
   - add HWDB entry for GC8000 Nano Ultra VIP r6205"

* tag 'drm-next-2025-12-03' of https://gitlab.freedesktop.org/drm/kernel: (1869 commits)
  Revert "drm/amd: Skip power ungate during suspend for VPE"
  drm/amdgpu: use common defines for HUB faults
  drm/amdgpu/gmc12: add amdgpu_vm_handle_fault() handling
  drm/amdgpu/gmc11: add amdgpu_vm_handle_fault() handling
  drm/amdgpu: use static ids for ACP platform devs
  drm/amdgpu/sdma6: Update SDMA 6.0.3 FW version to include UMQ protected-fence fix
  drm/amdgpu: Forward VMID reservation errors
  drm/amdgpu/gmc8: Delegate VM faults to soft IRQ handler ring
  drm/amdgpu/gmc7: Delegate VM faults to soft IRQ handler ring
  drm/amdgpu/gmc6: Delegate VM faults to soft IRQ handler ring
  drm/amdgpu/gmc6: Cache VM fault info
  drm/amdgpu/gmc6: Don't print MC client as it's unknown
  drm/amdgpu/cz_ih: Enable soft IRQ handler ring
  drm/amdgpu/tonga_ih: Enable soft IRQ handler ring
  drm/amdgpu/iceland_ih: Enable soft IRQ handler ring
  drm/amdgpu/cik_ih: Enable soft IRQ handler ring
  drm/amdgpu/si_ih: Enable soft IRQ handler ring
  drm/amd/display: fix typo in display_mode_core_structs.h
  drm/amd/display: fix Smart Power OLED not working after S4
  drm/amd/display: Move RGB-type check for audio sync to DCE HW sequence
  ...

rust: enable slice_flatten feature and provide it through an extension trait

2025-11-14T11:25:57+00:00

In Rust 1.80, the previously unstable `slice::flatten` family of methods
have been stabilized and renamed to `slice::as_flattened`.

This creates an issue as we want to use `as_flattened`, but need to
support the MSRV (which at the moment is Rust 1.78) where it is named
`flatten`.

Solve this by enabling the `slice_flatten` feature, and providing an
`as_flattened` implementation through an extension trait for compiler
versions where it is not available.

The trait is then exported from the prelude, making the `as_flattened`
family of methods transparently available for all supported compiler
versions.

This extension trait can be removed once the MSRV passes 1.80.

Suggested-by: Miguel Ojeda 
Link: https://lore.kernel.org/all/CANiq72kK4pG=O35NwxPNoTO17oRcg1yfGcvr3==Fi4edr+sfmw@mail.gmail.com/
Acked-by: Danilo Krummrich 
Acked-by: Miguel Ojeda 
Reviewed-by: Alice Ryhl 
Signed-off-by: Alexandre Courbot 
Message-ID: <20251110-gsp_boot-v9-8-8ae4058e3c0e@nvidia.com>
Message-ID: <20251104-b4-as-flattened-v3-1-6cb9c26b45cd@nvidia.com>

rust: replace `CStr` with `core::ffi::CStr`

2025-10-22T05:47:27+00:00

`kernel::ffi::CStr` was introduced in commit d126d2380131 ("rust: str:
add `CStr` type") in November 2022 as an upstreaming of earlier work
that was done in May 2021[0]. That earlier work, having predated the
inclusion of `CStr` in `core`, largely duplicated the implementation of
`std::ffi::CStr`.

`std::ffi::CStr` was moved to `core::ffi::CStr` in Rust 1.64 in
September 2022. Hence replace `kernel::str::CStr` with `core::ffi::CStr`
to reduce our custom code footprint, and retain needed custom
functionality through an extension trait.

Add `CStr` to `ffi` and the kernel prelude.

Link: https://github.com/Rust-for-Linux/linux/commit/faa3cbcca03d0dec8f8e43f1d8d5c0860d98a23f [0]
Acked-by: Greg Kroah-Hartman 
Reviewed-by: Alice Ryhl 
Acked-by: Danilo Krummrich 
Reviewed-by: Benno Lossin 
Signed-off-by: Tamir Duberstein 
Link: https://patch.msgid.link/20251018-cstr-core-v18-16-9378a54385f8@gmail.com
[ Removed assert that would now depend on the Rust version. - Miguel ]
Signed-off-by: Miguel Ojeda

rust: support formatting of foreign types

2025-10-22T05:15:31+00:00

Introduce a `fmt!` macro which wraps all arguments in
`kernel::fmt::Adapter` and a `kernel::fmt::Display` trait. This enables
formatting of foreign types (like `core::ffi::CStr`) that do not
implement `core::fmt::Display` due to concerns around lossy conversions
which do not apply in the kernel.

Suggested-by: Alice Ryhl 
Link: https://rust-for-linux.zulipchat.com/#narrow/channel/288089-General/topic/Custom.20formatting/with/516476467
Acked-by: Greg Kroah-Hartman 
Reviewed-by: Alice Ryhl 
Acked-by: Danilo Krummrich 
Reviewed-by: Benno Lossin 
Signed-off-by: Tamir Duberstein 
Link: https://patch.msgid.link/20251018-cstr-core-v18-15-9378a54385f8@gmail.com
Signed-off-by: Miguel Ojeda

rust: prelude: re-export `core::mem::{align,size}_of{,_val}`

2025-09-07T22:11:19+00:00

Rust 1.80.0 added:

    align_of
    align_of_val
    size_of
    size_of_val

from `core::mem` to the prelude [1].

For similar reasons, and to minimize potential confusion when code may
work in later versions but not in our current minimum, add it to our
prelude too.

Link: https://github.com/rust-lang/rust/pull/123168 [1]
Link: https://lore.kernel.org/rust-for-linux/CANiq72kOLYR2A95o0ji2mDmEqOKh9e9_60zZKmgF=vZmsW6DRg@mail.gmail.com/ [2]
Reviewed-by: Alice Ryhl 
Reviewed-by: Alexandre Courbot 
Reviewed-by: Andreas Hindborg 
Reviewed-by: Daniel Almeida 
Reviewed-by: Benno Lossin 
Signed-off-by: Miguel Ojeda

rust: kernel: remove `fmt!`, fix clippy::uninlined-format-args

2025-07-20T23:15:51+00:00

Rather than export a macro that delegates to `core::format_args`, simply
re-export `core::format_args` as `fmt` from the prelude. This exposes
clippy warnings which were previously obscured by this macro, such as:

    warning: variables can be used directly in the `format!` string
      --> ../drivers/cpufreq/rcpufreq_dt.rs:21:43
       |
    21 |     let prop_name = CString::try_from_fmt(fmt!("{}-supply", name)).ok()?;
       |                                           ^^^^^^^^^^^^^^^^^^^^^^^
       |
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
       = note: `-W clippy::uninlined-format-args` implied by `-W clippy::all`
       = help: to override `-W clippy::all` add `#[allow(clippy::uninlined_format_args)]`
    help: change this to
       |
    21 -     let prop_name = CString::try_from_fmt(fmt!("{}-supply", name)).ok()?;
    21 +     let prop_name = CString::try_from_fmt(fmt!("{name}-supply")).ok()?;
       |

Thus fix them in the same commit. This could possibly be fixed in two
stages, but the diff is small enough (outside of kernel/str.rs) that I
hope it can be taken in a single commit.

Signed-off-by: Tamir Duberstein 
Reviewed-by: Benno Lossin 
Reviewed-by: Alice Ryhl 
Acked-by: Danilo Krummrich 
Link: https://lore.kernel.org/r/20250704-core-cstr-prepare-v1-1-a91524037783@gmail.com
Signed-off-by: Miguel Ojeda

rust: uaccess: use newtype for user pointers

2025-07-14T21:52:45+00:00

Currently, Rust code uses a typedef for unsigned long to represent
userspace addresses. This is unfortunate because it means that userspace
addresses could accidentally be mixed up with other integers. To
alleviate that, we introduce a new UserPtr struct that wraps a raw
pointer to represent a userspace address. By using a struct, type
checking enforces that userspace addresses cannot be mixed up with
anything else.

This is similar to the __user annotation in C that detects cases where
user pointers are mixed with non-user pointers.

Note that unlike __user pointers in C, this type is just a pointer
without a target type. This means that it can't detect cases such as
mixing up which struct this user pointer references. However, that is
okay due to the way this is intended to be used - generally, you create
a UserPtr in your ioctl callback from the provided usize *before*
dispatching on which ioctl is in use, and then after dispatching on the
ioctl you pass the UserPtr into a UserSliceReader or UserSliceWriter;
selecting the target type does not happen until you have obtained the
UserSliceReader/Writer.

The UserPtr type is not marked with #[derive(Debug)], which means that
it's not possible to print values of this type. This avoids ASLR
leakage.

The type is added to the prelude as it is a fairly fundamental type
similar to c_int. The wrapping_add() method is renamed to
wrapping_byte_add() for consistency with the method name found on raw
pointers.

Reviewed-by: Benno Lossin 
Reviewed-by: Danilo Krummrich 
Reviewed-by: Christian Schrefl 
Reviewed-by: Boqun Feng 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Alice Ryhl 
Link: https://lore.kernel.org/r/20250616-userptr-newtype-v3-1-5ff7b2d18d9e@google.com
[ Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda

rust: add `kunit_tests` to the prelude

2025-05-27T18:09:59+00:00

It is convenient to have certain things in the `kernel` prelude, and
means kernel developers will find it even easier to start writing tests.

And, anyway, nobody should need to use this identifier for anything else.

Thus add it to the prelude.

Reviewed-by: David Gow 
Acked-by: Danilo Krummrich 
Link: https://lore.kernel.org/r/20250502215133.1923676-4-ojeda@kernel.org
Signed-off-by: Miguel Ojeda

rust: add C FFI types to the prelude

2025-05-23T14:31:43+00:00

Rust kernel code is supposed to use the custom mapping of C FFI types,
i.e. those from the `ffi` crate, rather than the ones coming from `core`.

Thus, to minimize mistakes and to simplify the code everywhere, just
provide them in the `kernel` prelude and ask in the Coding Guidelines
to use them directly, i.e. as a single segment path.

After this lands, we can start cleaning up the existing users.

Ideally, we would use something like Clippy's `disallowed-types` to
prevent the use of the `core` ones, but that one sees through aliases.

Link: https://lore.kernel.org/rust-for-linux/CANiq72kc4gzfieD-FjuWfELRDXXD2vLgPv4wqk3nt4pjdPQ=qg@mail.gmail.com/
Reviewed-by: Danilo Krummrich 
Reviewed-by: Alice Ryhl 
Link: https://lore.kernel.org/r/20250413005650.1745894-1-ojeda@kernel.org
[ Reworded content of the documentation to focus on how to use the
  aliases first. - Miguel ]
Signed-off-by: Miguel Ojeda

rust: make pin-init its own crate

2025-03-16T20:59:19+00:00

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 
Reviewed-by: Fiona Behrens 
Tested-by: Andreas Hindborg 
Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda