1158 static int queue_empty(struct apm_user *as)  in queue_empty()  argument
1160 	return as->event_head == as->event_tail;  in queue_empty()
1163 static apm_event_t get_queued_event(struct apm_user *as)  in get_queued_event()  argument
1165 	if (++as->event_tail >= APM_MAX_EVENTS)  in get_queued_event()
1166 		as->event_tail = 0;  in get_queued_event()
1167 	return as->events[as->event_tail];  in get_queued_event()
1172 	struct apm_user *as;  in queue_event()  local
1177 	for (as = user_list; as != NULL; as = as->next) {  in queue_event()
1178 		if ((as == sender) || (!as->reader))  in queue_event()
1180 		if (++as->event_head >= APM_MAX_EVENTS)  in queue_event()
1181 			as->event_head = 0;  in queue_event()
1183 		if (as->event_head == as->event_tail) {  in queue_event()
1188 			if (++as->event_tail >= APM_MAX_EVENTS)  in queue_event()
1189 				as->event_tail = 0;  in queue_event()
1191 		as->events[as->event_head] = event;  in queue_event()
1192 		if (!as->suser || !as->writer)  in queue_event()
1197 			as->suspends_pending++;  in queue_event()
1203 			as->standbys_pending++;  in queue_event()
1233 	struct apm_user	*as;  in suspend()  local
1265 	for (as = user_list; as != NULL; as = as->next) {  in suspend()
1266 		as->suspend_wait = 0;  in suspend()
1267 		as->suspend_result = err;  in suspend()
1447 static int check_apm_user(struct apm_user *as, const char *func)  in check_apm_user()  argument
1449 	if (as == NULL || as->magic != APM_BIOS_MAGIC) {  in check_apm_user()
1458 	struct apm_user *as;  in do_read()  local
1462 	as = fp->private_data;  in do_read()
1463 	if (check_apm_user(as, "read"))  in do_read()
1467 	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))  in do_read()
1469 	wait_event_interruptible(apm_waitqueue, !queue_empty(as));  in do_read()
1471 	while ((i >= sizeof(event)) && !queue_empty(as)) {  in do_read()
1472 		event = get_queued_event(as);  in do_read()
1481 			as->suspends_read++;  in do_read()
1486 			as->standbys_read++;  in do_read()
1501 	struct apm_user *as;  in do_poll()  local
1503 	as = fp->private_data;  in do_poll()
1504 	if (check_apm_user(as, "poll"))  in do_poll()
1507 	if (!queue_empty(as))  in do_poll()
1514 	struct apm_user *as;  in do_ioctl()  local
1517 	as = filp->private_data;  in do_ioctl()
1518 	if (check_apm_user(as, "ioctl"))  in do_ioctl()
1520 	if (!as->suser || !as->writer)  in do_ioctl()
1525 		if (as->standbys_read > 0) {  in do_ioctl()
1526 			as->standbys_read--;  in do_ioctl()
1527 			as->standbys_pending--;  in do_ioctl()
1530 			queue_event(APM_USER_STANDBY, as);  in do_ioctl()
1537 		if (as->suspends_read > 0) {  in do_ioctl()
1538 			as->suspends_read--;  in do_ioctl()
1539 			as->suspends_pending--;  in do_ioctl()
1542 			queue_event(APM_USER_SUSPEND, as);  in do_ioctl()
1547 			as->suspend_wait = 1;  in do_ioctl()
1550 					as->suspend_wait == 0);  in do_ioctl()
1551 			ret = as->suspend_result;  in do_ioctl()
1562 	struct apm_user *as;  in do_release()  local
1564 	as = filp->private_data;  in do_release()
1565 	if (check_apm_user(as, "release"))  in do_release()
1568 	if (as->standbys_pending > 0) {  in do_release()
1569 		standbys_pending -= as->standbys_pending;  in do_release()
1573 	if (as->suspends_pending > 0) {  in do_release()
1574 		suspends_pending -= as->suspends_pending;  in do_release()
1579 	if (user_list == as)  in do_release()
1580 		user_list = as->next;  in do_release()
1585 		     (as1 != NULL) && (as1->next != as);  in do_release()
1591 			as1->next = as->next;  in do_release()
1594 	kfree(as);  in do_release()
1600 	struct apm_user *as;  in do_open()  local
1602 	as = kmalloc(sizeof(*as), GFP_KERNEL);  in do_open()
1603 	if (as == NULL) {  in do_open()
1605 		       sizeof(*as));  in do_open()
1608 	as->magic = APM_BIOS_MAGIC;  in do_open()
1609 	as->event_tail = as->event_head = 0;  in do_open()
1610 	as->suspends_pending = as->standbys_pending = 0;  in do_open()
1611 	as->suspends_read = as->standbys_read = 0;  in do_open()
1619 	as->suser = capable(CAP_SYS_ADMIN);  in do_open()
1620 	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;  in do_open()
1621 	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;  in do_open()
1623 	as->next = user_list;  in do_open()
1624 	user_list = as;  in do_open()
1626 	filp->private_data = as;  in do_open()