diff options
Diffstat (limited to 'drivers/s390/char/sclp_quiesce.c')
| -rw-r--r-- | drivers/s390/char/sclp_quiesce.c | 83 |
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); |