aboutsummaryrefslogtreecommitdiffstats
path: root/rust
diff options
context:
space:
mode:
Diffstat (limited to 'rust')
-rw-r--r--rust/Makefile1
-rw-r--r--rust/bindings/bindings_helper.h1
-rw-r--r--rust/helpers/completion.c8
-rw-r--r--rust/helpers/cpu.c8
-rw-r--r--rust/helpers/helpers.c3
-rw-r--r--rust/helpers/poll.c10
-rw-r--r--rust/kernel/cpu.rs125
-rw-r--r--rust/kernel/cpufreq.rs199
-rw-r--r--rust/kernel/cpumask.rs64
-rw-r--r--rust/kernel/devres.rs60
-rw-r--r--rust/kernel/drm/device.rs12
-rw-r--r--rust/kernel/drm/driver.rs1
-rw-r--r--rust/kernel/firmware.rs2
-rw-r--r--rust/kernel/init.rs8
-rw-r--r--rust/kernel/kunit.rs2
-rw-r--r--rust/kernel/lib.rs3
-rw-r--r--rust/kernel/opp.rs8
-rw-r--r--rust/kernel/revocable.rs18
-rw-r--r--rust/kernel/sync.rs2
-rw-r--r--rust/kernel/sync/completion.rs112
-rw-r--r--rust/kernel/sync/poll.rs68
-rw-r--r--rust/kernel/time/hrtimer.rs2
-rw-r--r--rust/macros/module.rs10
23 files changed, 556 insertions, 171 deletions
diff --git a/rust/Makefile b/rust/Makefile
index 27dec7904c3a..115b63b7d1e3 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -194,6 +194,7 @@ quiet_cmd_rustdoc_test = RUSTDOC T $<
RUST_MODFILE=test.rs \
OBJTREE=$(abspath $(objtree)) \
$(RUSTDOC) --test $(rust_common_flags) \
+ -Zcrate-attr='feature(used_with_arg)' \
@$(objtree)/include/generated/rustc_cfg \
$(rustc_target_flags) $(rustdoc_test_target_flags) \
$(rustdoc_test_quiet) \
diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index bc494745f67b..8cbb660e2ec2 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -39,6 +39,7 @@
#include <linux/blk_types.h>
#include <linux/blkdev.h>
#include <linux/clk.h>
+#include <linux/completion.h>
#include <linux/configfs.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
diff --git a/rust/helpers/completion.c b/rust/helpers/completion.c
new file mode 100644
index 000000000000..b2443262a2ae
--- /dev/null
+++ b/rust/helpers/completion.c
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/completion.h>
+
+void rust_helper_init_completion(struct completion *x)
+{
+ init_completion(x);
+}
diff --git a/rust/helpers/cpu.c b/rust/helpers/cpu.c
new file mode 100644
index 000000000000..824e0adb19d4
--- /dev/null
+++ b/rust/helpers/cpu.c
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/smp.h>
+
+unsigned int rust_helper_raw_smp_processor_id(void)
+{
+ return raw_smp_processor_id();
+}
diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c
index 0f1b5d115985..d2887e3b2826 100644
--- a/rust/helpers/helpers.c
+++ b/rust/helpers/helpers.c
@@ -13,6 +13,8 @@
#include "build_assert.c"
#include "build_bug.c"
#include "clk.c"
+#include "completion.c"
+#include "cpu.c"
#include "cpufreq.c"
#include "cpumask.c"
#include "cred.c"
@@ -30,6 +32,7 @@
#include "platform.c"
#include "pci.c"
#include "pid_namespace.c"
+#include "poll.c"
#include "rbtree.c"
#include "rcu.c"
#include "refcount.c"
diff --git a/rust/helpers/poll.c b/rust/helpers/poll.c
new file mode 100644
index 000000000000..7e5b1751c2d5
--- /dev/null
+++ b/rust/helpers/poll.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/export.h>
+#include <linux/poll.h>
+
+void rust_helper_poll_wait(struct file *filp, wait_queue_head_t *wait_address,
+ poll_table *p)
+{
+ poll_wait(filp, wait_address, p);
+}
diff --git a/rust/kernel/cpu.rs b/rust/kernel/cpu.rs
index 10c5c3b25873..b75403b0eb56 100644
--- a/rust/kernel/cpu.rs
+++ b/rust/kernel/cpu.rs
@@ -6,6 +6,127 @@
use crate::{bindings, device::Device, error::Result, prelude::ENODEV};
+/// Returns the maximum number of possible CPUs in the current system configuration.
+#[inline]
+pub fn nr_cpu_ids() -> u32 {
+ #[cfg(any(NR_CPUS_1, CONFIG_FORCE_NR_CPUS))]
+ {
+ bindings::NR_CPUS
+ }
+
+ #[cfg(not(any(NR_CPUS_1, CONFIG_FORCE_NR_CPUS)))]
+ // SAFETY: `nr_cpu_ids` is a valid global provided by the kernel.
+ unsafe {
+ bindings::nr_cpu_ids
+ }
+}
+
+/// The CPU ID.
+///
+/// Represents a CPU identifier as a wrapper around an [`u32`].
+///
+/// # Invariants
+///
+/// The CPU ID lies within the range `[0, nr_cpu_ids())`.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::cpu::CpuId;
+///
+/// let cpu = 0;
+///
+/// // SAFETY: 0 is always a valid CPU number.
+/// let id = unsafe { CpuId::from_u32_unchecked(cpu) };
+///
+/// assert_eq!(id.as_u32(), cpu);
+/// assert!(CpuId::from_i32(0).is_some());
+/// assert!(CpuId::from_i32(-1).is_none());
+/// ```
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+pub struct CpuId(u32);
+
+impl CpuId {
+ /// Creates a new [`CpuId`] from the given `id` without checking bounds.
+ ///
+ /// # Safety
+ ///
+ /// The caller must ensure that `id` is a valid CPU ID (i.e., `0 <= id < nr_cpu_ids()`).
+ #[inline]
+ pub unsafe fn from_i32_unchecked(id: i32) -> Self {
+ debug_assert!(id >= 0);
+ debug_assert!((id as u32) < nr_cpu_ids());
+
+ // INVARIANT: The function safety guarantees `id` is a valid CPU id.
+ Self(id as u32)
+ }
+
+ /// Creates a new [`CpuId`] from the given `id`, checking that it is valid.
+ pub fn from_i32(id: i32) -> Option<Self> {
+ if id < 0 || id as u32 >= nr_cpu_ids() {
+ None
+ } else {
+ // INVARIANT: `id` has just been checked as a valid CPU ID.
+ Some(Self(id as u32))
+ }
+ }
+
+ /// Creates a new [`CpuId`] from the given `id` without checking bounds.
+ ///
+ /// # Safety
+ ///
+ /// The caller must ensure that `id` is a valid CPU ID (i.e., `0 <= id < nr_cpu_ids()`).
+ #[inline]
+ pub unsafe fn from_u32_unchecked(id: u32) -> Self {
+ debug_assert!(id < nr_cpu_ids());
+
+ // Ensure the `id` fits in an [`i32`] as it's also representable that way.
+ debug_assert!(id <= i32::MAX as u32);
+
+ // INVARIANT: The function safety guarantees `id` is a valid CPU id.
+ Self(id)
+ }
+
+ /// Creates a new [`CpuId`] from the given `id`, checking that it is valid.
+ pub fn from_u32(id: u32) -> Option<Self> {
+ if id >= nr_cpu_ids() {
+ None
+ } else {
+ // INVARIANT: `id` has just been checked as a valid CPU ID.
+ Some(Self(id))
+ }
+ }
+
+ /// Returns CPU number.
+ #[inline]
+ pub fn as_u32(&self) -> u32 {
+ self.0
+ }
+
+ /// Returns the ID of the CPU the code is currently running on.
+ ///
+ /// The returned value is considered unstable because it may change
+ /// unexpectedly due to preemption or CPU migration. It should only be
+ /// used when the context ensures that the task remains on the same CPU
+ /// or the users could use a stale (yet valid) CPU ID.
+ pub fn current() -> Self {
+ // SAFETY: raw_smp_processor_id() always returns a valid CPU ID.
+ unsafe { Self::from_u32_unchecked(bindings::raw_smp_processor_id()) }
+ }
+}
+
+impl From<CpuId> for u32 {
+ fn from(id: CpuId) -> Self {
+ id.as_u32()
+ }
+}
+
+impl From<CpuId> for i32 {
+ fn from(id: CpuId) -> Self {
+ id.as_u32() as i32
+ }
+}
+
/// Creates a new instance of CPU's device.
///
/// # Safety
@@ -17,9 +138,9 @@ use crate::{bindings, device::Device, error::Result, prelude::ENODEV};
/// Callers must ensure that the CPU device is not used after it has been unregistered.
/// This can be achieved, for example, by registering a CPU hotplug notifier and removing
/// any references to the CPU device within the notifier's callback.
-pub unsafe fn from_cpu(cpu: u32) -> Result<&'static Device> {
+pub unsafe fn from_cpu(cpu: CpuId) -> Result<&'static Device> {
// SAFETY: It is safe to call `get_cpu_device()` for any CPU.
- let ptr = unsafe { bindings::get_cpu_device(cpu) };
+ let ptr = unsafe { bindings::get_cpu_device(u32::from(cpu)) };
if ptr.is_null() {
return Err(ENODEV);
}
diff --git a/rust/kernel/cpufreq.rs b/rust/kernel/cpufreq.rs
index b0a9c6182aec..d6a14239f4ba 100644
--- a/rust/kernel/cpufreq.rs
+++ b/rust/kernel/cpufreq.rs
@@ -10,6 +10,7 @@
use crate::{
clk::Hertz,
+ cpu::CpuId,
cpumask,
device::{Bound, Device},
devres::Devres,
@@ -465,8 +466,9 @@ impl Policy {
/// Returns the primary CPU for the [`Policy`].
#[inline]
- pub fn cpu(&self) -> u32 {
- self.as_ref().cpu
+ pub fn cpu(&self) -> CpuId {
+ // SAFETY: The C API guarantees that `cpu` refers to a valid CPU number.
+ unsafe { CpuId::from_u32_unchecked(self.as_ref().cpu) }
}
/// Returns the minimum frequency for the [`Policy`].
@@ -525,7 +527,7 @@ impl Policy {
#[inline]
pub fn generic_get(&self) -> Result<u32> {
// SAFETY: By the type invariant, the pointer stored in `self` is valid.
- Ok(unsafe { bindings::cpufreq_generic_get(self.cpu()) })
+ Ok(unsafe { bindings::cpufreq_generic_get(u32::from(self.cpu())) })
}
/// Provides a wrapper to the register with energy model using the OPP core.
@@ -678,9 +680,9 @@ impl Policy {
struct PolicyCpu<'a>(&'a mut Policy);
impl<'a> PolicyCpu<'a> {
- fn from_cpu(cpu: u32) -> Result<Self> {
+ fn from_cpu(cpu: CpuId) -> Result<Self> {
// SAFETY: It is safe to call `cpufreq_cpu_get` for any valid CPU.
- let ptr = from_err_ptr(unsafe { bindings::cpufreq_cpu_get(cpu) })?;
+ let ptr = from_err_ptr(unsafe { bindings::cpufreq_cpu_get(u32::from(cpu)) })?;
Ok(Self(
// SAFETY: The `ptr` is guaranteed to be valid and remains valid for the lifetime of
@@ -1055,8 +1057,11 @@ impl<T: Driver> Registration<T> {
impl<T: Driver> Registration<T> {
/// Driver's `init` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn init_callback(ptr: *mut bindings::cpufreq_policy) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn init_callback(ptr: *mut bindings::cpufreq_policy) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1070,8 +1075,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `exit` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn exit_callback(ptr: *mut bindings::cpufreq_policy) {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn exit_callback(ptr: *mut bindings::cpufreq_policy) {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
let policy = unsafe { Policy::from_raw_mut(ptr) };
@@ -1082,8 +1090,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `online` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn online_callback(ptr: *mut bindings::cpufreq_policy) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn online_callback(ptr: *mut bindings::cpufreq_policy) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1094,8 +1105,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `offline` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn offline_callback(ptr: *mut bindings::cpufreq_policy) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn offline_callback(ptr: *mut bindings::cpufreq_policy) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1106,8 +1120,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `suspend` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn suspend_callback(ptr: *mut bindings::cpufreq_policy) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn suspend_callback(ptr: *mut bindings::cpufreq_policy) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1118,8 +1135,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `resume` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn resume_callback(ptr: *mut bindings::cpufreq_policy) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn resume_callback(ptr: *mut bindings::cpufreq_policy) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1130,8 +1150,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `ready` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn ready_callback(ptr: *mut bindings::cpufreq_policy) {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn ready_callback(ptr: *mut bindings::cpufreq_policy) {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
let policy = unsafe { Policy::from_raw_mut(ptr) };
@@ -1140,8 +1163,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `verify` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn verify_callback(ptr: *mut bindings::cpufreq_policy_data) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn verify_callback(ptr: *mut bindings::cpufreq_policy_data) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1152,8 +1178,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `setpolicy` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn setpolicy_callback(ptr: *mut bindings::cpufreq_policy) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn setpolicy_callback(ptr: *mut bindings::cpufreq_policy) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1164,12 +1193,15 @@ impl<T: Driver> Registration<T> {
/// Driver's `target` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn target_callback(
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn target_callback(
ptr: *mut bindings::cpufreq_policy,
- target_freq: u32,
- relation: u32,
- ) -> kernel::ffi::c_int {
+ target_freq: c_uint,
+ relation: c_uint,
+ ) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1180,11 +1212,14 @@ impl<T: Driver> Registration<T> {
/// Driver's `target_index` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn target_index_callback(
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn target_index_callback(
ptr: *mut bindings::cpufreq_policy,
- index: u32,
- ) -> kernel::ffi::c_int {
+ index: c_uint,
+ ) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1200,11 +1235,14 @@ impl<T: Driver> Registration<T> {
/// Driver's `fast_switch` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn fast_switch_callback(
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn fast_switch_callback(
ptr: *mut bindings::cpufreq_policy,
- target_freq: u32,
- ) -> kernel::ffi::c_uint {
+ target_freq: c_uint,
+ ) -> c_uint {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
let policy = unsafe { Policy::from_raw_mut(ptr) };
@@ -1212,24 +1250,34 @@ impl<T: Driver> Registration<T> {
}
/// Driver's `adjust_perf` callback.
- extern "C" fn adjust_perf_callback(
- cpu: u32,
- min_perf: usize,
- target_perf: usize,
- capacity: usize,
+ ///
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ unsafe extern "C" fn adjust_perf_callback(
+ cpu: c_uint,
+ min_perf: c_ulong,
+ target_perf: c_ulong,
+ capacity: c_ulong,
) {
- if let Ok(mut policy) = PolicyCpu::from_cpu(cpu) {
+ // SAFETY: The C API guarantees that `cpu` refers to a valid CPU number.
+ let cpu_id = unsafe { CpuId::from_u32_unchecked(cpu) };
+
+ if let Ok(mut policy) = PolicyCpu::from_cpu(cpu_id) {
T::adjust_perf(&mut policy, min_perf, target_perf, capacity);
}
}
/// Driver's `get_intermediate` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn get_intermediate_callback(
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn get_intermediate_callback(
ptr: *mut bindings::cpufreq_policy,
- index: u32,
- ) -> kernel::ffi::c_uint {
+ index: c_uint,
+ ) -> c_uint {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
let policy = unsafe { Policy::from_raw_mut(ptr) };
@@ -1243,11 +1291,14 @@ impl<T: Driver> Registration<T> {
/// Driver's `target_intermediate` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn target_intermediate_callback(
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn target_intermediate_callback(
ptr: *mut bindings::cpufreq_policy,
- index: u32,
- ) -> kernel::ffi::c_int {
+ index: c_uint,
+ ) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1262,12 +1313,24 @@ impl<T: Driver> Registration<T> {
}
/// Driver's `get` callback.
- extern "C" fn get_callback(cpu: u32) -> kernel::ffi::c_uint {
- PolicyCpu::from_cpu(cpu).map_or(0, |mut policy| T::get(&mut policy).map_or(0, |f| f))
+ ///
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ unsafe extern "C" fn get_callback(cpu: c_uint) -> c_uint {
+ // SAFETY: The C API guarantees that `cpu` refers to a valid CPU number.
+ let cpu_id = unsafe { CpuId::from_u32_unchecked(cpu) };
+
+ PolicyCpu::from_cpu(cpu_id).map_or(0, |mut policy| T::get(&mut policy).map_or(0, |f| f))
}
/// Driver's `update_limit` callback.
- extern "C" fn update_limits_callback(ptr: *mut bindings::cpufreq_policy) {
+ ///
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn update_limits_callback(ptr: *mut bindings::cpufreq_policy) {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
let policy = unsafe { Policy::from_raw_mut(ptr) };
@@ -1276,10 +1339,16 @@ impl<T: Driver> Registration<T> {
/// Driver's `bios_limit` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn bios_limit_callback(cpu: i32, limit: *mut u32) -> kernel::ffi::c_int {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn bios_limit_callback(cpu: c_int, limit: *mut c_uint) -> c_int {
+ // SAFETY: The C API guarantees that `cpu` refers to a valid CPU number.
+ let cpu_id = unsafe { CpuId::from_i32_unchecked(cpu) };
+
from_result(|| {
- let mut policy = PolicyCpu::from_cpu(cpu as u32)?;
+ let mut policy = PolicyCpu::from_cpu(cpu_id)?;
// SAFETY: `limit` is guaranteed by the C code to be valid.
T::bios_limit(&mut policy, &mut (unsafe { *limit })).map(|()| 0)
@@ -1288,11 +1357,14 @@ impl<T: Driver> Registration<T> {
/// Driver's `set_boost` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn set_boost_callback(
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn set_boost_callback(
ptr: *mut bindings::cpufreq_policy,
- state: i32,
- ) -> kernel::ffi::c_int {
+ state: c_int,
+ ) -> c_int {
from_result(|| {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
@@ -1303,8 +1375,11 @@ impl<T: Driver> Registration<T> {
/// Driver's `register_em` callback.
///
- /// SAFETY: Called from C. Inputs must be valid pointers.
- extern "C" fn register_em_callback(ptr: *mut bindings::cpufreq_policy) {
+ /// # Safety
+ ///
+ /// - This function may only be called from the cpufreq C infrastructure.
+ /// - The pointer arguments must be valid pointers.
+ unsafe extern "C" fn register_em_callback(ptr: *mut bindings::cpufreq_policy) {
// SAFETY: The `ptr` is guaranteed to be valid by the contract with the C code for the
// lifetime of `policy`.
let policy = unsafe { Policy::from_raw_mut(ptr) };
diff --git a/rust/kernel/cpumask.rs b/rust/kernel/cpumask.rs
index c90bfac9346a..e07f8ff5e3fd 100644
--- a/rust/kernel/cpumask.rs
+++ b/rust/kernel/cpumask.rs
@@ -6,6 +6,7 @@
use crate::{
alloc::{AllocError, Flags},
+ cpu::CpuId,
prelude::*,
types::Opaque,
};
@@ -13,9 +14,6 @@ use crate::{
#[cfg(CONFIG_CPUMASK_OFFSTACK)]
use core::ptr::{self, NonNull};
-#[cfg(not(CONFIG_CPUMASK_OFFSTACK))]
-use core::mem::MaybeUninit;
-
use core::ops::{Deref, DerefMut};
/// A CPU Mask.
@@ -35,9 +33,10 @@ use core::ops::{Deref, DerefMut};
///
/// ```
/// use kernel::bindings;
+/// use kernel::cpu::CpuId;
/// use kernel::cpumask::Cpumask;
///
-/// fn set_clear_cpu(ptr: *mut bindings::cpumask, set_cpu: u32, clear_cpu: i32) {
+/// fn set_clear_cpu(ptr: *mut bindings::cpumask, set_cpu: CpuId, clear_cpu: CpuId) {
/// // SAFETY: The `ptr` is valid for writing and remains valid for the lifetime of the
/// // returned reference.
/// let mask = unsafe { Cpumask::as_mut_ref(ptr) };
@@ -90,9 +89,9 @@ impl Cpumask {
/// This mismatches kernel naming convention and corresponds to the C
/// function `__cpumask_set_cpu()`.
#[inline]
- pub fn set(&mut self, cpu: u32) {
+ pub fn set(&mut self, cpu: CpuId) {
// SAFETY: By the type invariant, `self.as_raw` is a valid argument to `__cpumask_set_cpu`.
- unsafe { bindings::__cpumask_set_cpu(cpu, self.as_raw()) };
+ unsafe { bindings::__cpumask_set_cpu(u32::from(cpu), self.as_raw()) };
}
/// Clear `cpu` in the cpumask.
@@ -101,19 +100,19 @@ impl Cpumask {
/// This mismatches kernel naming convention and corresponds to the C
/// function `__cpumask_clear_cpu()`.
#[inline]
- pub fn clear(&mut self, cpu: i32) {
+ pub fn clear(&mut self, cpu: CpuId) {
// SAFETY: By the type invariant, `self.as_raw` is a valid argument to
// `__cpumask_clear_cpu`.
- unsafe { bindings::__cpumask_clear_cpu(cpu, self.as_raw()) };
+ unsafe { bindings::__cpumask_clear_cpu(i32::from(cpu), self.as_raw()) };
}
/// Test `cpu` in the cpumask.
///
/// Equivalent to the kernel's `cpumask_test_cpu` API.
#[inline]
- pub fn test(&self, cpu: i32) -> bool {
+ pub fn test(&self, cpu: CpuId) -> bool {
// SAFETY: By the type invariant, `self.as_raw` is a valid argument to `cpumask_test_cpu`.
- unsafe { bindings::cpumask_test_cpu(cpu, self.as_raw()) }
+ unsafe { bindings::cpumask_test_cpu(i32::from(cpu), self.as_raw()) }
}
/// Set all CPUs in the cpumask.
@@ -178,21 +177,40 @@ impl Cpumask {
/// The following example demonstrates how to create and update a [`CpumaskVar`].
///
/// ```
+/// use kernel::cpu::CpuId;
/// use kernel::cpumask::CpumaskVar;
///
/// let mut mask = CpumaskVar::new_zero(GFP_KERNEL).unwrap();
///
/// assert!(mask.empty());
-/// mask.set(2);
-/// assert!(mask.test(2));
-/// mask.set(3);
-/// assert!(mask.test(3));
-/// assert_eq!(mask.weight(), 2);
+/// let mut count = 0;
+///
+/// let cpu2 = CpuId::from_u32(2);
+/// if let Some(cpu) = cpu2 {
+/// mask.set(cpu);
+/// assert!(mask.test(cpu));
+/// count += 1;
+/// }
+///
+/// let cpu3 = CpuId::from_u32(3);
+/// if let Some(cpu) = cpu3 {
+/// mask.set(cpu);
+/// assert!(mask.test(cpu));
+/// count += 1;
+/// }
+///
+/// assert_eq!(mask.weight(), count);
///
/// let mask2 = CpumaskVar::try_clone(&mask).unwrap();
-/// assert!(mask2.test(2));
-/// assert!(mask2.test(3));
-/// assert_eq!(mask2.weight(), 2);
+///
+/// if let Some(cpu) = cpu2 {
+/// assert!(mask2.test(cpu));
+/// }
+///
+/// if let Some(cpu) = cpu3 {
+/// assert!(mask2.test(cpu));
+/// }
+/// assert_eq!(mask2.weight(), count);
/// ```
pub struct CpumaskVar {
#[cfg(CONFIG_CPUMASK_OFFSTACK)]
@@ -218,10 +236,7 @@ impl CpumaskVar {
},
#[cfg(not(CONFIG_CPUMASK_OFFSTACK))]
- // SAFETY: FFI type is valid to be zero-initialized.
- //
- // INVARIANT: The associated memory is freed when the `CpumaskVar` goes out of scope.
- mask: unsafe { core::mem::zeroed() },
+ mask: Cpumask(Opaque::zeroed()),
})
}
@@ -245,10 +260,7 @@ impl CpumaskVar {
NonNull::new(ptr.cast()).ok_or(AllocError)?
},
#[cfg(not(CONFIG_CPUMASK_OFFSTACK))]
- // SAFETY: Guaranteed by the safety requirements of the function.
- //
- // INVARIANT: The associated memory is freed when the `CpumaskVar` goes out of scope.
- mask: unsafe { MaybeUninit::uninit().assume_init() },
+ mask: Cpumask(Opaque::uninit()),
})
}
diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs
index 0f79a2ec9474..57502534d985 100644
--- a/rust/kernel/devres.rs
+++ b/rust/kernel/devres.rs
@@ -12,26 +12,28 @@ use crate::{
error::{Error, Result},
ffi::c_void,
prelude::*,
- revocable::Revocable,
- sync::Arc,
+ revocable::{Revocable, RevocableGuard},
+ sync::{rcu, Arc, Completion},
types::ARef,
};
-use core::ops::Deref;
-
#[pin_data]
struct DevresInner<T> {
dev: ARef<Device>,
callback: unsafe extern "C" fn(*mut c_void),
#[pin]
data: Revocable<T>,
+ #[pin]
+ revoke: Completion,
}
/// This abstraction is meant to be used by subsystems to containerize [`Device`] bound resources to
/// manage their lifetime.
///
/// [`Device`] bound resources should be freed when either the resource goes out of scope or the
-/// [`Device`] is unbound respectively, depending on what happens first.
+/// [`Device`] is unbound respectively, depending on what happens first. In any case, it is always
+/// guaranteed that revoking the device resource is completed before the corresponding [`Device`]
+/// is unbound.
///
/// To achieve that [`Devres`] registers a devres callback on creation, which is called once the
/// [`Device`] is unbound, revoking access to the encapsulated resource (see also [`Revocable`]).
@@ -102,6 +104,7 @@ impl<T> DevresInner<T> {
dev: dev.into(),
callback: Self::devres_callback,
data <- Revocable::new(data),
+ revoke <- Completion::new(),
}),
flags,
)?;
@@ -130,26 +133,28 @@ impl<T> DevresInner<T> {
self as _
}
- fn remove_action(this: &Arc<Self>) {
+ fn remove_action(this: &Arc<Self>) -> bool {
// SAFETY:
// - `self.inner.dev` is a valid `Device`,
// - the `action` and `data` pointers are the exact same ones as given to devm_add_action()
// previously,
// - `self` is always valid, even if the action has been released already.
- let ret = unsafe {
+ let success = unsafe {
bindings::devm_remove_action_nowarn(
this.dev.as_raw(),
Some(this.callback),
this.as_ptr() as _,
)
- };
+ } == 0;
- if ret == 0 {
+ if success {
// SAFETY: We leaked an `Arc` reference to devm_add_action() in `DevresInner::new`; if
// devm_remove_action_nowarn() was successful we can (and have to) claim back ownership
// of this reference.
let _ = unsafe { Arc::from_raw(this.as_ptr()) };
}
+
+ success
}
#[allow(clippy::missing_safety_doc)]
@@ -161,7 +166,12 @@ impl<T> DevresInner<T> {
// `DevresInner::new`.
let inner = unsafe { Arc::from_raw(ptr) };
- inner.data.revoke();
+ if !inner.data.revoke() {
+ // If `revoke()` returns false, it means that `Devres::drop` already started revoking
+ // `inner.data` for us. Hence we have to wait until `Devres::drop()` signals that it
+ // completed revoking `inner.data`.
+ inner.revoke.wait_for_completion();
+ }
}
}
@@ -218,20 +228,36 @@ impl<T> Devres<T> {
// SAFETY: `dev` being the same device as the device this `Devres` has been created for
// proves that `self.0.data` hasn't been revoked and is guaranteed to not be revoked as
// long as `dev` lives; `dev` lives at least as long as `self`.
- Ok(unsafe { self.deref().access() })
+ Ok(unsafe { self.0.data.access() })
}
-}
-impl<T> Deref for Devres<T> {
- type Target = Revocable<T>;
+ /// [`Devres`] accessor for [`Revocable::try_access`].
+ pub fn try_access(&self) -> Option<RevocableGuard<'_, T>> {
+ self.0.data.try_access()
+ }
+
+ /// [`Devres`] accessor for [`Revocable::try_access_with`].
+ pub fn try_access_with<R, F: FnOnce(&T) -> R>(&self, f: F) -> Option<R> {
+ self.0.data.try_access_with(f)
+ }
- fn deref(&self) -> &Self::Target {
- &self.0.data
+ /// [`Devres`] accessor for [`Revocable::try_access_with_guard`].
+ pub fn try_access_with_guard<'a>(&'a self, guard: &'a rcu::Guard) -> Option<&'a T> {
+ self.0.data.try_access_with_guard(guard)
}
}
impl<T> Drop for Devres<T> {
fn drop(&mut self) {
- DevresInner::remove_action(&self.0);
+ // SAFETY: When `drop` runs, it is guaranteed that nobody is accessing the revocable data
+ // anymore, hence it is safe not to wait for the grace period to finish.
+ if unsafe { self.0.data.revoke_nosync() } {
+ // We revoked `self.0.data` before the devres action did, hence try to remove it.
+ if !DevresInner::remove_action(&self.0) {
+ // We could not remove the devres action, which means that it now runs concurrently,
+ // hence signal that `self.0.data` has been revoked successfully.
+ self.0.revoke.complete_all();
+ }
+ }
}
}
diff --git a/rust/kernel/drm/device.rs b/rust/kernel/drm/device.rs
index 624d7a4c83ea..14c1aa402951 100644
--- a/rust/kernel/drm/device.rs
+++ b/rust/kernel/drm/device.rs
@@ -66,7 +66,7 @@ impl<T: drm::Driver> Device<T> {
open: Some(drm::File::<T::File>::open_callback),
postclose: Some(drm::File::<T::File>::postclose_callback),
unload: None,
- release: None,
+ release: Some(Self::release),
master_set: None,
master_drop: None,
debugfs_init: None,
@@ -162,6 +162,16 @@ impl<T: drm::Driver> Device<T> {
// SAFETY: `ptr` is valid by the safety requirements of this function.
unsafe { &*ptr.cast() }
}
+
+ extern "C" fn release(ptr: *mut bindings::drm_device) {
+ // SAFETY: `ptr` is a valid pointer to a `struct drm_device` and embedded in `Self`.
+ let this = unsafe { Self::from_drm_device(ptr) };
+
+ // SAFETY:
+ // - When `release` runs it is guaranteed that there is no further access to `this`.
+ // - `this` is valid for dropping.
+ unsafe { core::ptr::drop_in_place(this) };
+ }
}
impl<T: drm::Driver> Deref for Device<T> {
diff --git a/rust/kernel/drm/driver.rs b/rust/kernel/drm/driver.rs
index acb638086131..af93d46d03d3 100644
--- a/rust/kernel/drm/driver.rs
+++ b/rust/kernel/drm/driver.rs
@@ -10,7 +10,6 @@ use crate::{
drm,
error::{to_result, Result},
prelude::*,
- str::CStr,
types::ARef,
};
use macros::vtable;
diff --git a/rust/kernel/firmware.rs b/rust/kernel/firmware.rs
index 2494c96e105f..4fe621f35716 100644
--- a/rust/kernel/firmware.rs
+++ b/rust/kernel/firmware.rs
@@ -202,7 +202,7 @@ macro_rules! module_firmware {
};
#[link_section = ".modinfo"]
- #[used]
+ #[used(compiler)]
static __MODULE_FIRMWARE: [u8; $($builder)*::create(__MODULE_FIRMWARE_PREFIX)
.build_length()] = $($builder)*::create(__MODULE_FIRMWARE_PREFIX).build();
};
diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index 8d228c237954..21ef202ab0db 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -231,14 +231,14 @@ macro_rules! try_init {
($(&$this:ident in)? $t:ident $(::<$($generics:ty),* $(,)?>)? {
$($fields:tt)*
}) => {
- ::pin_init::try_init!($(&$this in)? $t $(::<$($generics),* $(,)?>)? {
+ ::pin_init::try_init!($(&$this in)? $t $(::<$($generics),*>)? {
$($fields)*
}? $crate::error::Error)
};
($(&$this:ident in)? $t:ident $(::<$($generics:ty),* $(,)?>)? {
$($fields:tt)*
}? $err:ty) => {
- ::pin_init::try_init!($(&$this in)? $t $(::<$($generics),* $(,)?>)? {
+ ::pin_init::try_init!($(&$this in)? $t $(::<$($generics),*>)? {
$($fields)*
}? $err)
};
@@ -291,14 +291,14 @@ macro_rules! try_pin_init {
($(&$this:ident in)? $t:ident $(::<$($generics:ty),* $(,)?>)? {
$($fields:tt)*
}) => {
- ::pin_init::try_pin_init!($(&$this in)? $t $(::<$($generics),* $(,)?>)? {
+ ::pin_init::try_pin_init!($(&$this in)? $t $(::<$($generics),*>)? {
$($fields)*
}? $crate::error::Error)
};
($(&$this:ident in)? $t:ident $(::<$($generics:ty),* $(,)?>)? {
$($fields:tt)*
}? $err:ty) => {
- ::pin_init::try_pin_init!($(&$this in)? $t $(::<$($generics),* $(,)?>)? {
+ ::pin_init::try_pin_init!($(&$this in)? $t $(::<$($generics),*>)? {
$($fields)*
}? $err)
};
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 4b8cdcb21e77..b9e65905e121 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -302,7 +302,7 @@ macro_rules! kunit_unsafe_test_suite {
is_init: false,
};
- #[used]
+ #[used(compiler)]
#[allow(unused_unsafe)]
#[cfg_attr(not(target_os = "macos"), link_section = ".kunit_test_suites")]
static mut KUNIT_TEST_SUITE_ENTRY: *const ::kernel::bindings::kunit_suite =
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 6b4774b2b1c3..e13d6ed88fa6 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -34,6 +34,9 @@
// Expected to become stable.
#![feature(arbitrary_self_types)]
//
+// To be determined.
+#![feature(used_with_arg)]
+//
// `feature(derive_coerce_pointee)` is expected to become stable. Before Rust
// 1.84.0, it did not exist, so enable the predecessor features.
#![cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, feature(derive_coerce_pointee))]
diff --git a/rust/kernel/opp.rs b/rust/kernel/opp.rs
index a566fc3e7dcb..846583da9a2f 100644
--- a/rust/kernel/opp.rs
+++ b/rust/kernel/opp.rs
@@ -514,9 +514,9 @@ impl<T: ConfigOps + Default> Config<T> {
dev: *mut bindings::device,
opp_table: *mut bindings::opp_table,
opp: *mut bindings::dev_pm_opp,
- _data: *mut kernel::ffi::c_void,
+ _data: *mut c_void,
scaling_down: bool,
- ) -> kernel::ffi::c_int {
+ ) -> c_int {
from_result(|| {
// SAFETY: 'dev' is guaranteed by the C code to be valid.
let dev = unsafe { Device::get_device(dev) };
@@ -540,8 +540,8 @@ impl<T: ConfigOps + Default> Config<T> {
old_opp: *mut bindings::dev_pm_opp,
new_opp: *mut bindings::dev_pm_opp,
regulators: *mut *mut bindings::regulator,
- count: kernel::ffi::c_uint,
- ) -> kernel::ffi::c_int {
+ count: c_uint,
+ ) -> c_int {
from_result(|| {
// SAFETY: 'dev' is guaranteed by the C code to be valid.
let dev = unsafe { Device::get_device(dev) };
diff --git a/rust/kernel/revocable.rs b/rust/kernel/revocable.rs
index db4aa46bb121..06a3cdfce344 100644
--- a/rust/kernel/revocable.rs
+++ b/rust/kernel/revocable.rs
@@ -154,8 +154,10 @@ impl<T> Revocable<T> {
/// # Safety
///
/// Callers must ensure that there are no more concurrent users of the revocable object.
- unsafe fn revoke_internal<const SYNC: bool>(&self) {
- if self.is_available.swap(false, Ordering::Relaxed) {
+ unsafe fn revoke_internal<const SYNC: bool>(&self) -> bool {
+ let revoke = self.is_available.swap(false, Ordering::Relaxed);
+
+ if revoke {
if SYNC {
// SAFETY: Just an FFI call, there are no further requirements.
unsafe { bindings::synchronize_rcu() };
@@ -165,6 +167,8 @@ impl<T> Revocable<T> {
// `compare_exchange` above that takes `is_available` from `true` to `false`.
unsafe { drop_in_place(self.data.get()) };
}
+
+ revoke
}
/// Revokes access to and drops the wrapped object.
@@ -172,10 +176,13 @@ impl<T> Revocable<T> {
/// Access to the object is revoked immediately to new callers of [`Revocable::try_access`],
/// expecting that there are no concurrent users of the object.
///
+ /// Returns `true` if `&self` has been revoked with this call, `false` if it was revoked
+ /// already.
+ ///
/// # Safety
///
/// Callers must ensure that there are no more concurrent users of the revocable object.
- pub unsafe fn revoke_nosync(&self) {
+ pub unsafe fn revoke_nosync(&self) -> bool {
// SAFETY: By the safety requirement of this function, the caller ensures that nobody is
// accessing the data anymore and hence we don't have to wait for the grace period to
// finish.
@@ -189,7 +196,10 @@ impl<T> Revocable<T> {
/// If there are concurrent users of the object (i.e., ones that called
/// [`Revocable::try_access`] beforehand and still haven't dropped the returned guard), this
/// function waits for the concurrent access to complete before dropping the wrapped object.
- pub fn revoke(&self) {
+ ///
+ /// Returns `true` if `&self` has been revoked with this call, `false` if it was revoked
+ /// already.
+ pub fn revoke(&self) -> bool {
// SAFETY: By passing `true` we ask `revoke_internal` to wait for the grace period to
// finish.
unsafe { self.revoke_internal::<true>() }
diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
index 36a719015583..c23a12639924 100644
--- a/rust/kernel/sync.rs
+++ b/rust/kernel/sync.rs
@@ -10,6 +10,7 @@ use crate::types::Opaque;
use pin_init;
mod arc;
+pub mod completion;
mod condvar;
pub mod lock;
mod locked_by;
@@ -17,6 +18,7 @@ pub mod poll;
pub mod rcu;
pub use arc::{Arc, ArcBorrow, UniqueArc};
+pub use completion::Completion;
pub use condvar::{new_condvar, CondVar, CondVarTimeoutResult};
pub use lock::global::{global_lock, GlobalGuard, GlobalLock, GlobalLockBackend, GlobalLockedBy};
pub use lock::mutex::{new_mutex, Mutex, MutexGuard};
diff --git a/rust/kernel/sync/completion.rs b/rust/kernel/sync/completion.rs
new file mode 100644
index 000000000000..c50012a940a3
--- /dev/null
+++ b/rust/kernel/sync/completion.rs
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Completion support.
+//!
+//! Reference: <https://docs.kernel.org/scheduler/completion.html>
+//!
+//! C header: [`include/linux/completion.h`](srctree/include/linux/completion.h)
+
+use crate::{bindings, prelude::*, types::Opaque};
+
+/// Synchronization primitive to signal when a certain task has been completed.
+///
+/// The [`Completion`] synchronization primitive signals when a certain task has been completed by
+/// waking up other tasks that have been queued up to wait for the [`Completion`] to be completed.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::sync::{Arc, Completion};
+/// use kernel::workqueue::{self, impl_has_work, new_work, Work, WorkItem};
+///
+/// #[pin_data]
+/// struct MyTask {
+/// #[pin]
+/// work: Work<MyTask>,
+/// #[pin]
+/// done: Completion,
+/// }
+///
+/// impl_has_work! {
+/// impl HasWork<Self> for MyTask { self.work }
+/// }
+///
+/// impl MyTask {
+/// fn new() -> Result<Arc<Self>> {
+/// let this = Arc::pin_init(pin_init!(MyTask {
+/// work <- new_work!("MyTask::work"),
+/// done <- Completion::new(),
+/// }), GFP_KERNEL)?;
+///
+/// let _ = workqueue::system().enqueue(this.clone());
+///
+/// Ok(this)
+/// }
+///
+/// fn wait_for_completion(&self) {
+/// self.done.wait_for_completion();
+///
+/// pr_info!("Completion: task complete\n");
+/// }
+/// }
+///
+/// impl WorkItem for MyTask {
+/// type Pointer = Arc<MyTask>;
+///
+/// fn run(this: Arc<MyTask>) {
+/// // process this task
+/// this.done.complete_all();
+/// }
+/// }
+///
+/// let task = MyTask::new()?;
+/// task.wait_for_completion();
+/// # Ok::<(), Error>(())
+/// ```
+#[pin_data]
+pub struct Completion {
+ #[pin]
+ inner: Opaque<bindings::completion>,
+}
+
+// SAFETY: `Completion` is safe to be send to any task.
+unsafe impl Send for Completion {}
+
+// SAFETY: `Completion` is safe to be accessed concurrently.
+unsafe impl Sync for Completion {}
+
+impl Completion {
+ /// Create an initializer for a new [`Completion`].
+ pub fn new() -> impl PinInit<Self> {
+ pin_init!(Self {
+ inner <- Opaque::ffi_init(|slot: *mut bindings::completion| {
+ // SAFETY: `slot` is a valid pointer to an uninitialized `struct completion`.
+ unsafe { bindings::init_completion(slot) };
+ }),
+ })
+ }
+
+ fn as_raw(&self) -> *mut bindings::completion {
+ self.inner.get()
+ }
+
+ /// Signal all tasks waiting on this completion.
+ ///
+ /// This method wakes up all tasks waiting on this completion; after this operation the
+ /// completion is permanently done, i.e. signals all current and future waiters.
+ pub fn complete_all(&self) {
+ // SAFETY: `self.as_raw()` is a pointer to a valid `struct completion`.
+ unsafe { bindings::complete_all(self.as_raw()) };
+ }
+
+ /// Wait for completion of a task.
+ ///
+ /// This method waits for the completion of a task; it is not interruptible and there is no
+ /// timeout.
+ ///
+ /// See also [`Completion::complete_all`].
+ pub fn wait_for_completion(&self) {
+ // SAFETY: `self.as_raw()` is a pointer to a valid `struct completion`.
+ unsafe { bindings::wait_for_completion(self.as_raw()) };
+ }
+}
diff --git a/rust/kernel/sync/poll.rs b/rust/kernel/sync/poll.rs
index d7e6e59e124b..69f1368a2151 100644
--- a/rust/kernel/sync/poll.rs
+++ b/rust/kernel/sync/poll.rs
@@ -9,9 +9,8 @@ use crate::{
fs::File,
prelude::*,
sync::{CondVar, LockClassKey},
- types::Opaque,
};
-use core::ops::Deref;
+use core::{marker::PhantomData, ops::Deref};
/// Creates a [`PollCondVar`] initialiser with the given name and a newly-created lock class.
#[macro_export]
@@ -23,58 +22,43 @@ macro_rules! new_poll_condvar {
};
}
-/// Wraps the kernel's `struct poll_table`.
+/// Wraps the kernel's `poll_table`.
///
/// # Invariants
///
-/// This struct contains a valid `struct poll_table`.
-///
-/// For a `struct poll_table` to be valid, its `_qproc` function must follow the safety
-/// requirements of `_qproc` functions:
-///
-/// * The `_qproc` function is given permission to enqueue a waiter to the provided `poll_table`
-/// during the call. Once the waiter is removed and an rcu grace period has passed, it must no
-/// longer access the `wait_queue_head`.
+/// The pointer must be null or reference a valid `poll_table`.
#[repr(transparent)]
-pub struct PollTable(Opaque<bindings::poll_table>);
+pub struct PollTable<'a> {
+ table: *mut bindings::poll_table,
+ _lifetime: PhantomData<&'a bindings::poll_table>,
+}
-impl PollTable {
- /// Creates a reference to a [`PollTable`] from a valid pointer.
+impl<'a> PollTable<'a> {
+ /// Creates a [`PollTable`] from a valid pointer.
///
/// # Safety
///
- /// The caller must ensure that for the duration of `'a`, the pointer will point at a valid poll
- /// table (as defined in the type invariants).
- ///
- /// The caller must also ensure that the `poll_table` is only accessed via the returned
- /// reference for the duration of `'a`.
- pub unsafe fn from_ptr<'a>(ptr: *mut bindings::poll_table) -> &'a mut PollTable {
- // SAFETY: The safety requirements guarantee the validity of the dereference, while the
- // `PollTable` type being transparent makes the cast ok.
- unsafe { &mut *ptr.cast() }
- }
-
- fn get_qproc(&self) -> bindings::poll_queue_proc {
- let ptr = self.0.get();
- // SAFETY: The `ptr` is valid because it originates from a reference, and the `_qproc`
- // field is not modified concurrently with this call since we have an immutable reference.
- unsafe { (*ptr)._qproc }
+ /// The pointer must be null or reference a valid `poll_table` for the duration of `'a`.
+ pub unsafe fn from_raw(table: *mut bindings::poll_table) -> Self {
+ // INVARIANTS: The safety requirements are the same as the struct invariants.
+ PollTable {
+ table,
+ _lifetime: PhantomData,
+ }
}
/// Register this [`PollTable`] with the provided [`PollCondVar`], so that it can be notified
/// using the condition variable.
- pub fn register_wait(&mut self, file: &File, cv: &PollCondVar) {
- if let Some(qproc) = self.get_qproc() {
- // SAFETY: The pointers to `file` and `self` need to be valid for the duration of this
- // call to `qproc`, which they are because they are references.
- //
- // The `cv.wait_queue_head` pointer must be valid until an rcu grace period after the
- // waiter is removed. The `PollCondVar` is pinned, so before `cv.wait_queue_head` can
- // be destroyed, the destructor must run. That destructor first removes all waiters,
- // and then waits for an rcu grace period. Therefore, `cv.wait_queue_head` is valid for
- // long enough.
- unsafe { qproc(file.as_ptr() as _, cv.wait_queue_head.get(), self.0.get()) };
- }
+ pub fn register_wait(&self, file: &File, cv: &PollCondVar) {
+ // SAFETY:
+ // * `file.as_ptr()` references a valid file for the duration of this call.
+ // * `self.table` is null or references a valid poll_table for the duration of this call.
+ // * Since `PollCondVar` is pinned, its destructor is guaranteed to run before the memory
+ // containing `cv.wait_queue_head` is invalidated. Since the destructor clears all
+ // waiters and then waits for an rcu grace period, it's guaranteed that
+ // `cv.wait_queue_head` remains valid for at least an rcu grace period after the removal
+ // of the last waiter.
+ unsafe { bindings::poll_wait(file.as_ptr(), cv.wait_queue_head.get(), self.table) }
}
}
diff --git a/rust/kernel/time/hrtimer.rs b/rust/kernel/time/hrtimer.rs
index 9df3dcd2fa39..36e1290cd079 100644
--- a/rust/kernel/time/hrtimer.rs
+++ b/rust/kernel/time/hrtimer.rs
@@ -517,7 +517,7 @@ macro_rules! impl_has_hr_timer {
) -> *mut Self {
// SAFETY: As per the safety requirement of this function, `ptr`
// is pointing inside a `$timer_type`.
- unsafe { ::kernel::container_of!(ptr, $timer_type, $field).cast_mut() }
+ unsafe { ::kernel::container_of!(ptr, $timer_type, $field) }
}
}
}
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index 2ddd2eeb2852..75efc6eeeafc 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -57,7 +57,7 @@ impl<'a> ModInfoBuilder<'a> {
{cfg}
#[doc(hidden)]
#[cfg_attr(not(target_os = \"macos\"), link_section = \".modinfo\")]
- #[used]
+ #[used(compiler)]
pub static __{module}_{counter}: [u8; {length}] = *{string};
",
cfg = if builtin {
@@ -249,7 +249,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
// key or a new section. For the moment, keep it simple.
#[cfg(MODULE)]
#[doc(hidden)]
- #[used]
+ #[used(compiler)]
static __IS_RUST_MODULE: () = ();
static mut __MOD: ::core::mem::MaybeUninit<{type_}> =
@@ -273,7 +273,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
#[cfg(MODULE)]
#[doc(hidden)]
- #[used]
+ #[used(compiler)]
#[link_section = \".init.data\"]
static __UNIQUE_ID___addressable_init_module: unsafe extern \"C\" fn() -> i32 = init_module;
@@ -293,7 +293,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
#[cfg(MODULE)]
#[doc(hidden)]
- #[used]
+ #[used(compiler)]
#[link_section = \".exit.data\"]
static __UNIQUE_ID___addressable_cleanup_module: extern \"C\" fn() = cleanup_module;
@@ -303,7 +303,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
#[cfg(not(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS))]
#[doc(hidden)]
#[link_section = \"{initcall_section}\"]
- #[used]
+ #[used(compiler)]
pub static __{ident}_initcall: extern \"C\" fn() ->
::kernel::ffi::c_int = __{ident}_init;
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-12 02:02:31 +0000