s390/char/sclp_quiesce.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *     signal quiesce handler
0004  *
0005  *  Copyright IBM Corp. 1999, 2004
0006  *  Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
0007  *             Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
0008  */
0009
0010 #include <linux/types.h>
0011 #include <linux/cpumask.h>
0012 #include <linux/smp.h>
0013 #include <linux/init.h>
0014 #include <linux/reboot.h>
0015 #include <linux/atomic.h>
0016 #include <asm/ptrace.h>
0017 #include <asm/smp.h>
0018
0019 #include "sclp.h"
0020
0021 /* Shutdown handler. Signal completion of shutdown by loading special PSW. */
0022 static void do_machine_quiesce(void)
0023 {
0024     psw_t quiesce_psw;
0025
0026     smp_send_stop();
0027     quiesce_psw.mask =
0028         PSW_MASK_BASE | PSW_MASK_EA | PSW_MASK_BA | PSW_MASK_WAIT;
0029     quiesce_psw.addr = 0xfff;
0030     __load_psw(quiesce_psw);
0031 }
0032
0033 /* Handler for quiesce event. Start shutdown procedure. */
0034 static void sclp_quiesce_handler(struct evbuf_header *evbuf)
0035 {
0036     _machine_restart = (void *) do_machine_quiesce;
0037     _machine_halt = do_machine_quiesce;
0038     _machine_power_off = do_machine_quiesce;
0039     ctrl_alt_del();
0040 }
0041
0042 static struct sclp_register sclp_quiesce_event = {
0043     .receive_mask = EVTYP_SIGQUIESCE_MASK,
0044     .receiver_fn = sclp_quiesce_handler,
0045 };
0046
0047 /* Initialize quiesce driver. */
0048 static int __init sclp_quiesce_init(void)
0049 {
0050     return sclp_register(&sclp_quiesce_event);
0051 }
0052 device_initcall(sclp_quiesce_init);