Re: [PATCH 2/7] vfio: Export unmap_mapping_range() wrapper

Peter Xu
2021-08-10T18:56:13Z

On Thu, Aug 05, 2021 at 11:07:22AM -0600, Alex Williamson wrote:
> +void vfio_device_unmap_mapping_range(struct vfio_device *device,
> + loff_t start, loff_t len)
> +{
> + unmap_mapping_range(device->inode->i_mapping, start, len, true);

(not a big deal, but still raise this up)

It seems to me VFIO MMIO regions do not allow private maps, so even_cow==true
should be the same with even_cow==false. even_cow==true will just check the
page mapping for each pte even though they should just all match, imho, so
logically "false" should work the same and should be tiny-little faster.

Thanks,

> +}
> +EXPORT_SYMBOL_GPL(vfio_device_unmap_mapping_range);

--
Peter Xu