/* Take pin on all head pages to avoid freeing them under us */
list_for_each_safe(pos, next, &list) {
page = list_entry((void *)pos, struct page, mapping);
page = compound_head(page);
/* Take pin on all head pages to avoid freeing them under us */
list_for_each_safe(pos, next, &list) {
page = list_entry((void *)pos, struct page, mapping);
page = compound_head(page);