[PATCH v2 1/5] rust: acpi: add `acpi::DeviceId` abstraction

Igor Korotin posted 5 patches 6 months, 2 weeks ago
There is a newer version of this series
[PATCH v2 1/5] rust: acpi: add `acpi::DeviceId` abstraction
Posted by Igor Korotin 6 months, 2 weeks ago
`acpi::DeviceId` is an abstraction around `struct acpi_device_id`.

This is used by subsequent patches, in particular the i2c driver
abstractions, to create ACPI device ID tables.

Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com>
---
 MAINTAINERS         |  1 +
 rust/kernel/acpi.rs | 62 +++++++++++++++++++++++++++++++++++++++++++++
 rust/kernel/lib.rs  |  1 +
 3 files changed, 64 insertions(+)
 create mode 100644 rust/kernel/acpi.rs

diff --git a/MAINTAINERS b/MAINTAINERS
index b659fb27ab63..5f8dfae08454 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -302,6 +302,7 @@ F:	include/linux/acpi.h
 F:	include/linux/fwnode.h
 F:	include/linux/fw_table.h
 F:	lib/fw_table.c
+F:	rust/kernel/acpi.rs
 F:	tools/power/acpi/
 
 ACPI APEI
diff --git a/rust/kernel/acpi.rs b/rust/kernel/acpi.rs
new file mode 100644
index 000000000000..2f526a0b2ed9
--- /dev/null
+++ b/rust/kernel/acpi.rs
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Advanced Configuration and Power Interface abstractions.
+
+use crate::{bindings, device_id::RawDeviceId, prelude::*};
+
+/// IdTable type for ACPI drivers.
+pub type IdTable<T> = &'static dyn kernel::device_id::IdTable<DeviceId, T>;
+
+/// An ACPI device id.
+#[repr(transparent)]
+#[derive(Clone, Copy)]
+pub struct DeviceId(bindings::acpi_device_id);
+
+// SAFETY:
+// * `DeviceId` is a `#[repr(transparent)` wrapper of `struct acpi_device_id` and does not add
+//   additional invariants, so it's safe to transmute to `RawType`.
+// * `DRIVER_DATA_OFFSET` is the offset to the `data` field.
+unsafe impl RawDeviceId for DeviceId {
+    type RawType = bindings::acpi_device_id;
+
+    const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::acpi_device_id, driver_data);
+
+    fn index(&self) -> usize {
+        self.0.driver_data as _
+    }
+}
+
+impl DeviceId {
+    const ACPI_ID_LEN: usize = 16;
+
+    /// Create a new device id from an ACPI 'id' string.
+    pub const fn new(id: &'static CStr) -> Self {
+        assert!(id.len() <= Self::ACPI_ID_LEN, "ID exceeds 16 bytes");
+        let src = id.as_bytes_with_nul();
+        // Replace with `bindings::acpi_device_id::default()` once stabilized for `const`.
+        // SAFETY: FFI type is valid to be zero-initialized.
+        let mut acpi: bindings::acpi_device_id = unsafe { core::mem::zeroed() };
+        let mut i = 0;
+        while i < src.len() {
+            acpi.id[i] = src[i];
+            i += 1;
+        }
+
+        Self(acpi)
+    }
+}
+
+/// Create an ACPI `IdTable` with an "alias" for modpost.
+#[macro_export]
+macro_rules! acpi_device_table {
+    ($table_name:ident, $module_table_name:ident, $id_info_type: ty, $table_data: expr) => {
+        const $table_name: $crate::device_id::IdArray<
+            $crate::acpi::DeviceId,
+            $id_info_type,
+            { $table_data.len() },
+        > = $crate::device_id::IdArray::new($table_data);
+
+        $crate::module_device_table!("acpi", $module_table_name, $table_name);
+    };
+}
+
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 6e9287136cac..c2761bc7cfe6 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -51,6 +51,7 @@
 
 pub use ffi;
 
+pub mod acpi;
 pub mod alloc;
 #[cfg(CONFIG_BLOCK)]
 pub mod block;
-- 
2.43.0
Re: [PATCH v2 1/5] rust: acpi: add `acpi::DeviceId` abstraction
Posted by kernel test robot 6 months, 2 weeks ago
Hi Igor,

kernel test robot noticed the following build errors:

[auto build test ERROR on char-misc/char-misc-testing]
[also build test ERROR on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.15 next-20250605]
[cannot apply to rust/rust-next driver-core/driver-core-testing driver-core/driver-core-next driver-core/driver-core-linus]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Igor-Korotin/rust-acpi-add-acpi-DeviceId-abstraction/20250606-042551
base:   char-misc/char-misc-testing
patch link:    https://lore.kernel.org/r/20250605162326.3659046-1-igor.korotin.linux%40gmail.com
patch subject: [PATCH v2 1/5] rust: acpi: add `acpi::DeviceId` abstraction
config: x86_64-rhel-9.4-rust (https://download.01.org/0day-ci/archive/20250606/202506060925.Thw3s9xE-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
rustc: rustc 1.78.0 (9b00956e5 2024-04-29)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250606/202506060925.Thw3s9xE-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202506060925.Thw3s9xE-lkp@intel.com/

All errors (new ones prefixed by >>):

   PATH=/opt/cross/clang-18/bin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
   INFO PATH=/opt/cross/rustc-1.78.0-bindgen-0.65.1/cargo/bin:/opt/cross/clang-18/bin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
   /usr/bin/timeout -k 100 12h /usr/bin/make KCFLAGS= -Wno-error=return-type -Wreturn-type -funsigned-char -Wundef W=1 --keep-going LLVM=1 -j32 -C source O=/kbuild/obj/consumer/x86_64-rhel-9.4-rust ARCH=x86_64 SHELL=/bin/bash rustfmtcheck
   make: Entering directory '/kbuild/src/consumer'
   make[1]: Entering directory '/kbuild/obj/consumer/x86_64-rhel-9.4-rust'
>> Diff in rust/kernel/acpi.rs at line 59:
            $crate::module_device_table!("acpi", $module_table_name, $table_name);
        };
    }
   -
    
>> Diff in rust/kernel/acpi.rs at line 59:
            $crate::module_device_table!("acpi", $module_table_name, $table_name);
        };
    }
   -
    
   make[2]: *** [Makefile:1826: rustfmt] Error 123
   make[2]: Target 'rustfmtcheck' not remade because of errors.
   make[1]: Leaving directory '/kbuild/obj/consumer/x86_64-rhel-9.4-rust'
   make[1]: *** [Makefile:248: __sub-make] Error 2
   make[1]: Target 'rustfmtcheck' not remade because of errors.
   make: *** [Makefile:248: __sub-make] Error 2
   make: Target 'rustfmtcheck' not remade because of errors.
   make: Leaving directory '/kbuild/src/consumer'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki