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-rw-r--r--rust/kernel/pci/id.rs6
-rw-r--r--rust/kernel/pci/io.rs144
-rw-r--r--rust/kernel/pci/irq.rs252
3 files changed, 401 insertions, 1 deletions
diff --git a/rust/kernel/pci/id.rs b/rust/kernel/pci/id.rs
index 5f5d59ff49fc..c09125946d9e 100644
--- a/rust/kernel/pci/id.rs
+++ b/rust/kernel/pci/id.rs
@@ -4,7 +4,11 @@
//!
//! This module contains PCI class codes, Vendor IDs, and supporting types.
-use crate::{bindings, error::code::EINVAL, error::Error, fmt, prelude::*};
+use crate::{
+ bindings,
+ fmt,
+ prelude::*, //
+};
/// PCI device class codes.
///
diff --git a/rust/kernel/pci/io.rs b/rust/kernel/pci/io.rs
new file mode 100644
index 000000000000..0d55c3139b6f
--- /dev/null
+++ b/rust/kernel/pci/io.rs
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! PCI memory-mapped I/O infrastructure.
+
+use super::Device;
+use crate::{
+ bindings,
+ device,
+ devres::Devres,
+ io::{
+ Io,
+ IoRaw, //
+ },
+ prelude::*,
+ sync::aref::ARef, //
+};
+use core::ops::Deref;
+
+/// A PCI BAR to perform I/O-Operations on.
+///
+/// # Invariants
+///
+/// `Bar` always holds an `IoRaw` inststance that holds a valid pointer to the start of the I/O
+/// memory mapped PCI BAR and its size.
+pub struct Bar<const SIZE: usize = 0> {
+ pdev: ARef<Device>,
+ io: IoRaw<SIZE>,
+ num: i32,
+}
+
+impl<const SIZE: usize> Bar<SIZE> {
+ pub(super) fn new(pdev: &Device, num: u32, name: &CStr) -> Result<Self> {
+ let len = pdev.resource_len(num)?;
+ if len == 0 {
+ return Err(ENOMEM);
+ }
+
+ // Convert to `i32`, since that's what all the C bindings use.
+ let num = i32::try_from(num)?;
+
+ // SAFETY:
+ // `pdev` is valid by the invariants of `Device`.
+ // `num` is checked for validity by a previous call to `Device::resource_len`.
+ // `name` is always valid.
+ let ret = unsafe { bindings::pci_request_region(pdev.as_raw(), num, name.as_char_ptr()) };
+ if ret != 0 {
+ return Err(EBUSY);
+ }
+
+ // SAFETY:
+ // `pdev` is valid by the invariants of `Device`.
+ // `num` is checked for validity by a previous call to `Device::resource_len`.
+ // `name` is always valid.
+ let ioptr: usize = unsafe { bindings::pci_iomap(pdev.as_raw(), num, 0) } as usize;
+ if ioptr == 0 {
+ // SAFETY:
+ // `pdev` valid by the invariants of `Device`.
+ // `num` is checked for validity by a previous call to `Device::resource_len`.
+ unsafe { bindings::pci_release_region(pdev.as_raw(), num) };
+ return Err(ENOMEM);
+ }
+
+ let io = match IoRaw::new(ioptr, len as usize) {
+ Ok(io) => io,
+ Err(err) => {
+ // SAFETY:
+ // `pdev` is valid by the invariants of `Device`.
+ // `ioptr` is guaranteed to be the start of a valid I/O mapped memory region.
+ // `num` is checked for validity by a previous call to `Device::resource_len`.
+ unsafe { Self::do_release(pdev, ioptr, num) };
+ return Err(err);
+ }
+ };
+
+ Ok(Bar {
+ pdev: pdev.into(),
+ io,
+ num,
+ })
+ }
+
+ /// # Safety
+ ///
+ /// `ioptr` must be a valid pointer to the memory mapped PCI BAR number `num`.
+ unsafe fn do_release(pdev: &Device, ioptr: usize, num: i32) {
+ // SAFETY:
+ // `pdev` is valid by the invariants of `Device`.
+ // `ioptr` is valid by the safety requirements.
+ // `num` is valid by the safety requirements.
+ unsafe {
+ bindings::pci_iounmap(pdev.as_raw(), ioptr as *mut c_void);
+ bindings::pci_release_region(pdev.as_raw(), num);
+ }
+ }
+
+ fn release(&self) {
+ // SAFETY: The safety requirements are guaranteed by the type invariant of `self.pdev`.
+ unsafe { Self::do_release(&self.pdev, self.io.addr(), self.num) };
+ }
+}
+
+impl Bar {
+ #[inline]
+ pub(super) fn index_is_valid(index: u32) -> bool {
+ // A `struct pci_dev` owns an array of resources with at most `PCI_NUM_RESOURCES` entries.
+ index < bindings::PCI_NUM_RESOURCES
+ }
+}
+
+impl<const SIZE: usize> Drop for Bar<SIZE> {
+ fn drop(&mut self) {
+ self.release();
+ }
+}
+
+impl<const SIZE: usize> Deref for Bar<SIZE> {
+ type Target = Io<SIZE>;
+
+ fn deref(&self) -> &Self::Target {
+ // SAFETY: By the type invariant of `Self`, the MMIO range in `self.io` is properly mapped.
+ unsafe { Io::from_raw(&self.io) }
+ }
+}
+
+impl Device<device::Bound> {
+ /// Maps an entire PCI BAR after performing a region-request on it. I/O operation bound checks
+ /// can be performed on compile time for offsets (plus the requested type size) < SIZE.
+ pub fn iomap_region_sized<'a, const SIZE: usize>(
+ &'a self,
+ bar: u32,
+ name: &'a CStr,
+ ) -> impl PinInit<Devres<Bar<SIZE>>, Error> + 'a {
+ Devres::new(self.as_ref(), Bar::<SIZE>::new(self, bar, name))
+ }
+
+ /// Maps an entire PCI BAR after performing a region-request on it.
+ pub fn iomap_region<'a>(
+ &'a self,
+ bar: u32,
+ name: &'a CStr,
+ ) -> impl PinInit<Devres<Bar>, Error> + 'a {
+ self.iomap_region_sized::<0>(bar, name)
+ }
+}
diff --git a/rust/kernel/pci/irq.rs b/rust/kernel/pci/irq.rs
new file mode 100644
index 000000000000..d9230e105541
--- /dev/null
+++ b/rust/kernel/pci/irq.rs
@@ -0,0 +1,252 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! PCI interrupt infrastructure.
+
+use super::Device;
+use crate::{
+ bindings,
+ device,
+ device::Bound,
+ devres,
+ error::to_result,
+ irq::{
+ self,
+ IrqRequest, //
+ },
+ prelude::*,
+ str::CStr,
+ sync::aref::ARef, //
+};
+use core::ops::RangeInclusive;
+
+/// IRQ type flags for PCI interrupt allocation.
+#[derive(Debug, Clone, Copy)]
+pub enum IrqType {
+ /// INTx interrupts.
+ Intx,
+ /// Message Signaled Interrupts (MSI).
+ Msi,
+ /// Extended Message Signaled Interrupts (MSI-X).
+ MsiX,
+}
+
+impl IrqType {
+ /// Convert to the corresponding kernel flags.
+ const fn as_raw(self) -> u32 {
+ match self {
+ IrqType::Intx => bindings::PCI_IRQ_INTX,
+ IrqType::Msi => bindings::PCI_IRQ_MSI,
+ IrqType::MsiX => bindings::PCI_IRQ_MSIX,
+ }
+ }
+}
+
+/// Set of IRQ types that can be used for PCI interrupt allocation.
+#[derive(Debug, Clone, Copy, Default)]
+pub struct IrqTypes(u32);
+
+impl IrqTypes {
+ /// Create a set containing all IRQ types (MSI-X, MSI, and INTx).
+ pub const fn all() -> Self {
+ Self(bindings::PCI_IRQ_ALL_TYPES)
+ }
+
+ /// Build a set of IRQ types.
+ ///
+ /// # Examples
+ ///
+ /// ```ignore
+ /// // Create a set with only MSI and MSI-X (no INTx interrupts).
+ /// let msi_only = IrqTypes::default()
+ /// .with(IrqType::Msi)
+ /// .with(IrqType::MsiX);
+ /// ```
+ pub const fn with(self, irq_type: IrqType) -> Self {
+ Self(self.0 | irq_type.as_raw())
+ }
+
+ /// Get the raw flags value.
+ const fn as_raw(self) -> u32 {
+ self.0
+ }
+}
+
+/// Represents an allocated IRQ vector for a specific PCI device.
+///
+/// This type ties an IRQ vector to the device it was allocated for,
+/// ensuring the vector is only used with the correct device.
+#[derive(Clone, Copy)]
+pub struct IrqVector<'a> {
+ dev: &'a Device<Bound>,
+ index: u32,
+}
+
+impl<'a> IrqVector<'a> {
+ /// Creates a new [`IrqVector`] for the given device and index.
+ ///
+ /// # Safety
+ ///
+ /// - `index` must be a valid IRQ vector index for `dev`.
+ /// - `dev` must point to a [`Device`] that has successfully allocated IRQ vectors.
+ unsafe fn new(dev: &'a Device<Bound>, index: u32) -> Self {
+ Self { dev, index }
+ }
+
+ /// Returns the raw vector index.
+ fn index(&self) -> u32 {
+ self.index
+ }
+}
+
+impl<'a> TryInto<IrqRequest<'a>> for IrqVector<'a> {
+ type Error = Error;
+
+ fn try_into(self) -> Result<IrqRequest<'a>> {
+ // SAFETY: `self.as_raw` returns a valid pointer to a `struct pci_dev`.
+ let irq = unsafe { bindings::pci_irq_vector(self.dev.as_raw(), self.index()) };
+ if irq < 0 {
+ return Err(crate::error::Error::from_errno(irq));
+ }
+ // SAFETY: `irq` is guaranteed to be a valid IRQ number for `&self`.
+ Ok(unsafe { IrqRequest::new(self.dev.as_ref(), irq as u32) })
+ }
+}
+
+/// Represents an IRQ vector allocation for a PCI device.
+///
+/// This type ensures that IRQ vectors are properly allocated and freed by
+/// tying the allocation to the lifetime of this registration object.
+///
+/// # Invariants
+///
+/// The [`Device`] has successfully allocated IRQ vectors.
+struct IrqVectorRegistration {
+ dev: ARef<Device>,
+}
+
+impl IrqVectorRegistration {
+ /// Allocate and register IRQ vectors for the given PCI device.
+ ///
+ /// Allocates IRQ vectors and registers them with devres for automatic cleanup.
+ /// Returns a range of valid IRQ vectors.
+ fn register<'a>(
+ dev: &'a Device<Bound>,
+ min_vecs: u32,
+ max_vecs: u32,
+ irq_types: IrqTypes,
+ ) -> Result<RangeInclusive<IrqVector<'a>>> {
+ // SAFETY:
+ // - `dev.as_raw()` is guaranteed to be a valid pointer to a `struct pci_dev`
+ // by the type invariant of `Device`.
+ // - `pci_alloc_irq_vectors` internally validates all other parameters
+ // and returns error codes.
+ let ret = unsafe {
+ bindings::pci_alloc_irq_vectors(dev.as_raw(), min_vecs, max_vecs, irq_types.as_raw())
+ };
+
+ to_result(ret)?;
+ let count = ret as u32;
+
+ // SAFETY:
+ // - `pci_alloc_irq_vectors` returns the number of allocated vectors on success.
+ // - Vectors are 0-based, so valid indices are [0, count-1].
+ // - `pci_alloc_irq_vectors` guarantees `count >= min_vecs > 0`, so both `0` and
+ // `count - 1` are valid IRQ vector indices for `dev`.
+ let range = unsafe { IrqVector::new(dev, 0)..=IrqVector::new(dev, count - 1) };
+
+ // INVARIANT: The IRQ vector allocation for `dev` above was successful.
+ let irq_vecs = Self { dev: dev.into() };
+ devres::register(dev.as_ref(), irq_vecs, GFP_KERNEL)?;
+
+ Ok(range)
+ }
+}
+
+impl Drop for IrqVectorRegistration {
+ fn drop(&mut self) {
+ // SAFETY:
+ // - By the type invariant, `self.dev.as_raw()` is a valid pointer to a `struct pci_dev`.
+ // - `self.dev` has successfully allocated IRQ vectors.
+ unsafe { bindings::pci_free_irq_vectors(self.dev.as_raw()) };
+ }
+}
+
+impl Device<device::Bound> {
+ /// Returns a [`kernel::irq::Registration`] for the given IRQ vector.
+ pub fn request_irq<'a, T: crate::irq::Handler + 'static>(
+ &'a self,
+ vector: IrqVector<'a>,
+ flags: irq::Flags,
+ name: &'static CStr,
+ handler: impl PinInit<T, Error> + 'a,
+ ) -> impl PinInit<irq::Registration<T>, Error> + 'a {
+ pin_init::pin_init_scope(move || {
+ let request = vector.try_into()?;
+
+ Ok(irq::Registration::<T>::new(request, flags, name, handler))
+ })
+ }
+
+ /// Returns a [`kernel::irq::ThreadedRegistration`] for the given IRQ vector.
+ pub fn request_threaded_irq<'a, T: crate::irq::ThreadedHandler + 'static>(
+ &'a self,
+ vector: IrqVector<'a>,
+ flags: irq::Flags,
+ name: &'static CStr,
+ handler: impl PinInit<T, Error> + 'a,
+ ) -> impl PinInit<irq::ThreadedRegistration<T>, Error> + 'a {
+ pin_init::pin_init_scope(move || {
+ let request = vector.try_into()?;
+
+ Ok(irq::ThreadedRegistration::<T>::new(
+ request, flags, name, handler,
+ ))
+ })
+ }
+
+ /// Allocate IRQ vectors for this PCI device with automatic cleanup.
+ ///
+ /// Allocates between `min_vecs` and `max_vecs` interrupt vectors for the device.
+ /// The allocation will use MSI-X, MSI, or INTx interrupts based on the `irq_types`
+ /// parameter and hardware capabilities. When multiple types are specified, the kernel
+ /// will try them in order of preference: MSI-X first, then MSI, then INTx interrupts.
+ ///
+ /// The allocated vectors are automatically freed when the device is unbound, using the
+ /// devres (device resource management) system.
+ ///
+ /// # Arguments
+ ///
+ /// * `min_vecs` - Minimum number of vectors required.
+ /// * `max_vecs` - Maximum number of vectors to allocate.
+ /// * `irq_types` - Types of interrupts that can be used.
+ ///
+ /// # Returns
+ ///
+ /// Returns a range of IRQ vectors that were successfully allocated, or an error if the
+ /// allocation fails or cannot meet the minimum requirement.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// # use kernel::{ device::Bound, pci};
+ /// # fn no_run(dev: &pci::Device<Bound>) -> Result {
+ /// // Allocate using any available interrupt type in the order mentioned above.
+ /// let vectors = dev.alloc_irq_vectors(1, 32, pci::IrqTypes::all())?;
+ ///
+ /// // Allocate MSI or MSI-X only (no INTx interrupts).
+ /// let msi_only = pci::IrqTypes::default()
+ /// .with(pci::IrqType::Msi)
+ /// .with(pci::IrqType::MsiX);
+ /// let vectors = dev.alloc_irq_vectors(4, 16, msi_only)?;
+ /// # Ok(())
+ /// # }
+ /// ```
+ pub fn alloc_irq_vectors(
+ &self,
+ min_vecs: u32,
+ max_vecs: u32,
+ irq_types: IrqTypes,
+ ) -> Result<RangeInclusive<IrqVector<'_>>> {
+ IrqVectorRegistration::register(self, min_vecs, max_vecs, irq_types)
+ }
+}
generated by cgit (git 2.34.1) at 2025-12-06 10:51:50 +0000