Re: [PATCH 1/8] rust: pci: add is_virtfn(), to check for VFs

Joel Fernandes
2025-12-07T06:28:23Z

On Wed, Nov 19, 2025 at 05:19:05PM -0500, Peter Colberg wrote:
> From: John Hubbard <jhubbard@nvidia.com>
>
> Add a method to check if a PCI device is a Virtual Function (VF) created
> through Single Root I/O Virtualization (SR-IOV).
>
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> Reviewed-by: Alistair Popple <apopple@nvidia.com>
> Signed-off-by: Peter Colberg <pcolberg@redhat.com>
> ---
> This patch was originally part of the series "rust: pci: expose
> is_virtfn() and reject VFs in nova-core" and modified as follows:
> - Replace true -> `true` in doc comment.
> - Shorten description and omit justification specific to nova-core.
>
> Link: https://lore.kernel.org/rust-for-linux/20250930220759.288528-2-jhubbard@nvidia.com/
> ---
> rust/kernel/pci.rs | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs
> index 82e128431f080fde78a06dc5c284ab12739e747e..c20b8daeb7aadbef9f6ecfc48c972436efac9a08 100644
> --- a/rust/kernel/pci.rs
> +++ b/rust/kernel/pci.rs
> @@ -409,6 +409,12 @@ pub fn resource_start(&self, bar: u32) -> Result<bindings::resource_size_t> {
> Ok(unsafe { bindings::pci_resource_start(self.as_raw(), bar.try_into()?) })
> }
>
> + /// Returns `true` if this device is a Virtual Function (VF).
> + pub fn is_virtfn(&self) -> bool {

Add #[inline] here and to `is_physfn()` similar to other methods in this struct?

With that,

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>

thanks,

- Joel

> + // SAFETY: `self.as_raw` is a valid pointer to a `struct pci_dev`.
> + unsafe { (*self.as_raw()).is_virtfn() != 0 }
> + }
> +
> /// Returns the size of the given PCI BAR resource.
> pub fn resource_len(&self, bar: u32) -> Result<bindings::resource_size_t> {
> if !Bar::index_is_valid(bar) {
>
> --
> 2.51.1
>