```
// Writes the root directory of the volume referred to by this object into
// directory.
status_t
BVolume::GetRootDirectory(BDirectory *directory) const
{
	// check parameter and initialization
	status_t error = (directory && InitCheck() == B_OK ? B_OK : B_BAD_VALUE);
	// get FS stat
	fs_info info;
	if (error == B_OK && fs_stat_dev(fDevice, &info) != 0)
		error = errno;
	// init the directory
	if (error == B_OK) {
		node_ref ref;
		ref.device = info.dev;
		ref.node = info.root;
		error = directory->SetTo(&ref);
	}
	return error;
}
```

Seems like it's safe to synthesize an `entry_ref` from information from `fs_stat_dev`.