Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 83 insertions, 0 deletions

diff --git a/drivers/s390/char/sclp_quiesce.c b/drivers/s390/char/sclp_quiesce.c
new file mode 100644
index 000000000..76956c213
--- /dev/null
+++ b/drivers/s390/char/sclp_quiesce.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *     signal quiesce handler
+ *
+ *  Copyright IBM Corp. 1999, 2004
+ *  Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *             Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <linux/cpumask.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/reboot.h>
+#include <linux/atomic.h>
+#include <asm/ptrace.h>
+#include <asm/smp.h>
+
+#include "sclp.h"
+
+static void (*old_machine_restart)(char *);
+static void (*old_machine_halt)(void);
+static void (*old_machine_power_off)(void);
+
+/* Shutdown handler. Signal completion of shutdown by loading special PSW. */
+static void do_machine_quiesce(void)
+{
+	psw_t quiesce_psw;
+
+	smp_send_stop();
+	quiesce_psw.mask =
+		PSW_MASK_BASE | PSW_MASK_EA | PSW_MASK_BA | PSW_MASK_WAIT;
+	quiesce_psw.addr = 0xfff;
+	__load_psw(quiesce_psw);
+}
+
+/* Handler for quiesce event. Start shutdown procedure. */
+static void sclp_quiesce_handler(struct evbuf_header *evbuf)
+{
+	if (_machine_restart != (void *) do_machine_quiesce) {
+		old_machine_restart = _machine_restart;
+		old_machine_halt = _machine_halt;
+		old_machine_power_off = _machine_power_off;
+		_machine_restart = (void *) do_machine_quiesce;
+		_machine_halt = do_machine_quiesce;
+		_machine_power_off = do_machine_quiesce;
+	}
+	ctrl_alt_del();
+}
+
+/* Undo machine restart/halt/power_off modification on resume */
+static void sclp_quiesce_pm_event(struct sclp_register *reg,
+				  enum sclp_pm_event sclp_pm_event)
+{
+	switch (sclp_pm_event) {
+	case SCLP_PM_EVENT_RESTORE:
+		if (old_machine_restart) {
+			_machine_restart = old_machine_restart;
+			_machine_halt = old_machine_halt;
+			_machine_power_off = old_machine_power_off;
+			old_machine_restart = NULL;
+			old_machine_halt = NULL;
+			old_machine_power_off = NULL;
+		}
+		break;
+	case SCLP_PM_EVENT_FREEZE:
+	case SCLP_PM_EVENT_THAW:
+		break;
+	}
+}
+
+static struct sclp_register sclp_quiesce_event = {
+	.receive_mask = EVTYP_SIGQUIESCE_MASK,
+	.receiver_fn = sclp_quiesce_handler,
+	.pm_event_fn = sclp_quiesce_pm_event
+};
+
+/* Initialize quiesce driver. */
+static int __init sclp_quiesce_init(void)
+{
+	return sclp_register(&sclp_quiesce_event);
+}
+device_initcall(sclp_quiesce_init);