Re: [PATCH v2 1/1] vfio/pci: Remove the core dependency on driver data

[Danilo Krummrich]

On Wed Sep 30, 2026 at 4:36 PM CEST, Simon Song wrote:
> vfio-pci-core currently has runtime functions that interpret pci
> driver_data as a pointer to vfio_pci_core_device, and enforce vfio
> variant drivers must set vfio_pci_core_device to their pci driver_data.
> This constrains variant drivers' private-data layout, including the
> typed driver data used by the Rust PCI infrastructure.
>
> Added VFIO_PCI_CORE_DEFINE_CALLBACKS marcos to generate wrapper code for
> each vfio variant driver, update vfio variant drivers to store their
> private strctures in driver_data and use generated wrapper to pass the
> vfio core device to helpers.
>
> Select the vga decode callback during vfio_pci_vga_init based on if
> vfio_vga_disabled, the callback only use pci_dev and does not require
> driver_data
>
> Assisted-by: LLM
> Link: https://lore.kernel.org/all/DLFD2ZDSK9YQ.3A4R66G8UJMD8@xxxxxxxxxx/
> Co-developed-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> Signed-off-by: Simon Song <xinmengs@xxxxxxxxxx>

I like that this moves the PM ops to static initialization. One nit below, but
either way:

Reviewed-by: Danilo Krummrich <dakr@xxxxxxxxxx>

> @@ -2332,10 +2324,9 @@ void vfio_pci_core_unregister_device(struct vfio_pci_core_device *vdev)
>  }
>  EXPORT_SYMBOL_GPL(vfio_pci_core_unregister_device);
>  
> -pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev,
> +pci_ers_result_t vfio_pci_core_aer_err_detected(struct vfio_pci_core_device *vdev,
>  						pci_channel_state_t state)

The state argument is unused. Since this is not installed as a direct PCI
callback anymore it technically doesn't need to retain its signature.