Implementation restriction: ContentDocumentLink requires a filter by a single Id on ContentDocumentId or LinkedEntityId using the equals operator or multiple Id's using the IN operator.
Map<Id, ContentVersion> mapCV = new Map<Id, ContentVersion>();
Set<Id> setId = mapCV.keyset();
List<ContentDocumentLink> listCDL = [SELECT LinkedEntityId, ContentDocumentId, Visibility
FROM ContentDocumentLink WHERE ContentDocumentId IN: setId];