On Thu, Aug 05, 2021 at 11:07:47AM -0600, Alex Williamson wrote: > diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c > index 1e4fc69fee7d..42ca93be152a 100644 > +++ b/drivers/vfio/vfio.c > @@ -875,6 +875,22 @@ struct vfio_device *vfio_device_get_from_dev(struct device *dev) > } > EXPORT_SYMBOL_GPL(vfio_device_get_from_dev); > > +static const struct file_operations vfio_device_fops; > + > +int vfio_device_vma_to_pfn(struct vfio_device *device, > + struct vm_area_struct *vma, unsigned long *pfn) A comment here describing the locking conditions the caller must meet would be a good addition.. It looks like this can only work under the i_mmap_lock and the returned pfn can only be taken outside that lock if it is placed in a VMA Maybe this is not a great API then? Should it be 'populate vma' and call io_remap_pfn_range under the op? Jason
