summaryrefslogtreecommitdiff
path: root/drivers/s390/char/sclp_quiesce.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/s390/char/sclp_quiesce.c')
-rw-r--r--drivers/s390/char/sclp_quiesce.c84
1 files changed, 84 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..475e470d9
--- /dev/null
+++ b/drivers/s390/char/sclp_quiesce.c
@@ -0,0 +1,84 @@
+/*
+ * 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/module.h>
+#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);
+}
+
+module_init(sclp_quiesce_init);