+/*
+ * This function is called when the system is being rebooted.
+ */
+static int
+xpc_system_reboot(struct notifier_block *nb, unsigned long event, void *unused)
+{
+ enum xpc_retval reason;
+
+
+ switch (event) {
+ case SYS_RESTART:
+ reason = xpcSystemReboot;
+ break;
+ case SYS_HALT:
+ reason = xpcSystemHalt;
+ break;
+ case SYS_POWER_OFF:
+ reason = xpcSystemPoweroff;
+ break;
+ default:
+ reason = xpcSystemGoingDown;
+ }
+
+ xpc_do_exit(reason);
+ return NOTIFY_DONE;
+}
+
+
+/*
+ * Notify other partitions to disengage from all references to our memory.
+ */
+static void
+xpc_die_disengage(void)
+{
+ struct xpc_partition *part;
+ partid_t partid;
+ unsigned long engaged;
+ long time, printmsg_time, disengage_request_timeout;
+
+
+ /* keep xpc_hb_checker thread from doing anything (just in case) */
+ xpc_exiting = 1;
+
+ xpc_vars->heartbeating_to_mask = 0; /* indicate we're deactivated */
+
+ for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
+ part = &xpc_partitions[partid];
+
+ if (!XPC_SUPPORTS_DISENGAGE_REQUEST(part->
+ remote_vars_version)) {
+
+ /* just in case it was left set by an earlier XPC */
+ xpc_clear_partition_engaged(1UL << partid);
+ continue;
+ }
+
+ if (xpc_partition_engaged(1UL << partid) ||
+ part->act_state != XPC_P_INACTIVE) {
+ xpc_request_partition_disengage(part);
+ xpc_mark_partition_disengaged(part);
+ xpc_IPI_send_disengage(part);
+ }
+ }
+
+ time = rtc_time();
+ printmsg_time = time +
+ (XPC_DISENGAGE_PRINTMSG_INTERVAL * sn_rtc_cycles_per_second);
+ disengage_request_timeout = time +
+ (xpc_disengage_request_timelimit * sn_rtc_cycles_per_second);
+
+ /* wait for all other partitions to disengage from us */
+
+ while (1) {
+ engaged = xpc_partition_engaged(-1UL);
+ if (!engaged) {
+ dev_info(xpc_part, "all partitions have disengaged\n");
+ break;
+ }
+
+ time = rtc_time();
+ if (time >= disengage_request_timeout) {
+ for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
+ if (engaged & (1UL << partid)) {
+ dev_info(xpc_part, "disengage from "
+ "remote partition %d timed "
+ "out\n", partid);
+ }
+ }
+ break;
+ }
+
+ if (time >= printmsg_time) {
+ dev_info(xpc_part, "waiting for remote partitions to "
+ "disengage, timeout in %ld seconds\n",
+ (disengage_request_timeout - time) /
+ sn_rtc_cycles_per_second);
+ printmsg_time = time +
+ (XPC_DISENGAGE_PRINTMSG_INTERVAL *
+ sn_rtc_cycles_per_second);
+ }
+ }
+}
+
+
+/*
+ * This function is called when the system is being restarted or halted due
+ * to some sort of system failure. If this is the case we need to notify the
+ * other partitions to disengage from all references to our memory.
+ * This function can also be called when our heartbeater could be offlined
+ * for a time. In this case we need to notify other partitions to not worry
+ * about the lack of a heartbeat.
+ */
+static int
+xpc_system_die(struct notifier_block *nb, unsigned long event, void *unused)
+{
+ switch (event) {
+ case DIE_MACHINE_RESTART:
+ case DIE_MACHINE_HALT:
+ xpc_die_disengage();
+ break;
+
+ case DIE_KDEBUG_ENTER:
+ /* Should lack of heartbeat be ignored by other partitions? */
+ if (!xpc_kdebug_ignore) {
+ break;
+ }
+ /* fall through */
+ case DIE_MCA_MONARCH_ENTER:
+ case DIE_INIT_MONARCH_ENTER:
+ xpc_vars->heartbeat++;
+ xpc_vars->heartbeat_offline = 1;
+ break;
+
+ case DIE_KDEBUG_LEAVE:
+ /* Is lack of heartbeat being ignored by other partitions? */
+ if (!xpc_kdebug_ignore) {
+ break;
+ }
+ /* fall through */
+ case DIE_MCA_MONARCH_LEAVE:
+ case DIE_INIT_MONARCH_LEAVE:
+ xpc_vars->heartbeat++;
+ xpc_vars->heartbeat_offline = 0;
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+