Re: [PATCH v9 1/1] rust: pci: add extended capability and SR-IOV support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Missing `#[inline]` attribute on small abstraction functions or functions forwarding to a C binding.
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commit d6c524351183fb31a687066514aecd0e51e1aadf
Author: Zhi Wang <zhiw@nvidia.com>

rust: pci: add extended capability and SR-IOV support

Rust PCI drivers have no typed interface for locating and accessing PCIe
extended capabilities. The SR-IOV extended capability describes VF topology
and VF BARs. Expose this information through the Rust PCI abstraction so
drivers can use the existing typed configuration-space accessors instead of
raw bindings.

Link: https://lore.kernel.org/rust-for-linux/20260818084633.1673214-2-zhiw@nvidia.com/

> diff --git a/rust/kernel/pci/cap.rs b/rust/kernel/pci/cap.rs
> new file mode 100644
> index 0000000000000..74cd9e50e919b
> --- /dev/null
> +++ b/rust/kernel/pci/cap.rs
[ ... ]
> +    ///     Ok(())
> +    /// }
> +    /// ```
> +    pub fn find_ext_capability<C: ExtCapability>(&self) -> Result<Option<ConfigSpace<'a, C>>> {

[Severity: Low]
Should this function be annotated with #[inline]?

This abstraction method in rust/kernel/pci/cap.rs forwards directly to the
bindings::pci_find_ext_capability C call. According to the Rust subsystem
guidelines, small functions or functions forwarding to a C binding call in
abstraction crates should be annotated with #[inline].

> +        let offset = usize::from(
> +            // SAFETY: `self.pdev` is valid by the type invariant of `ConfigSpace`.
> +            unsafe {
> +                bindings::pci_find_ext_capability(self.pdev.as_raw(), i32::from(C::ID.as_raw()))
> +            },
> +        );
[ ... ]
> +    /// Calculates the size of the extended capability at `offset`.
> +    ///
> +    /// The capability extends to the next extended capability, or to the end of the extended
> +    /// configuration space if it is the last one. `offset` must be a DWORD-aligned offset within
> +    /// the extended configuration space returned by `pci_find_ext_capability`. Returns an error if
> +    /// the capability header is outside the extended configuration space.
> +    fn calculate_ext_cap_size(&self, offset: usize) -> Result<usize> {

[Severity: Low]
Would it be appropriate to add the #[inline] attribute to this small
internal helper function as well?

> +        let header = self.try_read32(offset)?;
> +        // SAFETY: Pure bit manipulation, no preconditions.
> +        let next = casts::u32_as_usize(unsafe { bindings::pci_ext_cap_next(header) });
> +
> +        Ok(if next > offset {

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/2e9d992509299c2f13de48109c4c933f53817acb.1787830828.git.zhiw@nvidia.com?part=1