static __poll_t ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
			       void *priv)
{
	struct ep_send_events_data *esed = priv;
	__poll_t revents;
	struct epitem *epi, *tmp;
	struct epoll_event __user *uevent = esed->events;
	struct wakeup_source *ws;
	poll_table pt;

	init_poll_funcptr(&pt, NULL);
	esed->res = 0;

	/*
	 * We can loop without lock because we are passed a task private list.
	 * Items cannot vanish during the loop because ep_scan_ready_list() is
	 * holding "mtx" during this call.
	 */
	lockdep_assert_held(&ep->mtx);

	list_for_each_entry_safe(epi, tmp, head, rdllink) {
		if (esed->res >= esed->maxevents)
			break;

		/*
		 * Activate ep->ws before deactivating epi->ws to prevent
		 * triggering auto-suspend here (in case we reactive epi->ws
		 * below).
		 *
		 * This could be rearranged to delay the deactivation of epi->ws
		 * instead, but then epi->ws would temporarily be out of sync
		 * with ep_is_linked().
		 */
		ws = ep_wakeup_source(epi);
		if (ws) {
			if (ws->active)
				__pm_stay_awake(ep->ws);
			__pm_relax(ws);
		}

		list_del_init(&epi->rdllink);

		/*
		 * If the event mask intersect the caller-requested one,
		 * deliver the event to userspace. Again, ep_scan_ready_list()
		 * is holding ep->mtx, so no operations coming from userspace
		 * can change the item.
		 */
		revents = ep_item_poll(epi, &pt, 1);
		if (!revents)
			continue;

		if (__put_user(revents, &uevent->events) ||
		    __put_user(epi->event.data, &uevent->data)) {
			list_add(&epi->rdllink, head);
			ep_pm_stay_awake(epi);
			if (!esed->res)
				esed->res = -EFAULT;
			return 0;
		}
		esed->res++;
		uevent++;
		if (epi->event.events & EPOLLONESHOT)
			epi->event.events &= EP_PRIVATE_BITS;
		else if (!(epi->event.events & EPOLLET)) {
			/*
			 * If this file has been added with Level
			 * Trigger mode, we need to insert back inside
			 * the ready list, so that the next call to
			 * epoll_wait() will check again the events
			 * availability. At this point, no one can insert
			 * into ep->rdllist besides us. The epoll_ctl()
			 * callers are locked out by
			 * ep_scan_ready_list() holding "mtx" and the
			 * poll callback will queue them in ep->ovflist.
			 */
			list_add_tail(&epi->rdllink, &ep->rdllist);
			ep_pm_stay_awake(epi);
		}
	}

	return 0;
}
static __poll_t ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
			       void *priv)
{
	struct ep_send_events_data *esed = priv;
	__poll_t revents;
	struct epitem *epi, *tmp;
	struct epoll_event __user *uevent = esed->events;
	struct wakeup_source *ws;
	poll_table pt;

	init_poll_funcptr(&pt, NULL);
	esed->res = 0;

	 
	lockdep_assert_held(&ep->mtx);

	list_for_each_entry_safe(epi, tmp, head, rdllink) {
		if (esed->res >= esed->maxevents)
			break;

		 
		ws = ep_wakeup_source(epi);
		if (ws) {
			if (ws->active)
				__pm_stay_awake(ep->ws);
			__pm_relax(ws);
		}

		list_del_init(&epi->rdllink);

		 
		revents = ep_item_poll(epi, &pt, 1);
		if (!revents)
			continue;

		if (__put_user(revents, &uevent->events) ||
		    __put_user(epi->event.data, &uevent->data)) {
			list_add(&epi->rdllink, head);
			ep_pm_stay_awake(epi);
			if (!esed->res)
				esed->res = -EFAULT;
			return 0;
		}
		esed->res++;
		uevent++;
		if (epi->event.events & EPOLLONESHOT)
			epi->event.events &= EP_PRIVATE_BITS;
		else if (!(epi->event.events & EPOLLET)) {
			 
			list_add_tail(&epi->rdllink, &ep->rdllist);
			ep_pm_stay_awake(epi);
		}
	}

	return 0;
}