Re: [PATCH 4/5] vfio: Introduce vfio_device_ops.get_unmapped_area hook

[Jason Gunthorpe <jgg@nvidia.com>]

On Tue, Jun 17, 2025 at 11:39:07AM -0400, Peter Xu wrote:
>  
> +#ifdef CONFIG_ARCH_SUPPORTS_HUGE_PFNMAP
>  static unsigned long vfio_device_get_unmapped_area(struct file *file,
>                                                    unsigned long addr,
>                                                    unsigned long len,
> @@ -1370,6 +1371,7 @@ static unsigned long vfio_device_get_unmapped_area(struct file *file,
>         return device->ops->get_unmapped_area(device, file, addr, len,
>                                               pgoff, flags);
>  }
> +#endif
>  
>  const struct file_operations vfio_device_fops = {
>         .owner          = THIS_MODULE,
> @@ -1380,7 +1382,9 @@ const struct file_operations vfio_device_fops = {
>         .unlocked_ioctl = vfio_device_fops_unl_ioctl,
>         .compat_ioctl   = compat_ptr_ioctl,
>         .mmap           = vfio_device_fops_mmap,
> +#ifdef CONFIG_ARCH_SUPPORTS_HUGE_PFNMAP
>         .get_unmapped_area = vfio_device_get_unmapped_area,
> +#endif
>  };

IMHO this also seems like something the core code should be dealing
with and not putting weird ifdefs in drivers.

Jason