1/* 2 * signal quiesce handler 3 * 4 * Copyright IBM Corp. 1999, 2004 5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 6 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com> 7 */ 8 9#include <linux/module.h> 10#include <linux/types.h> 11#include <linux/cpumask.h> 12#include <linux/smp.h> 13#include <linux/init.h> 14#include <linux/reboot.h> 15#include <linux/atomic.h> 16#include <asm/ptrace.h> 17#include <asm/smp.h> 18 19#include "sclp.h" 20 21static void (*old_machine_restart)(char *); 22static void (*old_machine_halt)(void); 23static void (*old_machine_power_off)(void); 24 25/* Shutdown handler. Signal completion of shutdown by loading special PSW. */ 26static void do_machine_quiesce(void) 27{ 28 psw_t quiesce_psw; 29 30 smp_send_stop(); 31 quiesce_psw.mask = 32 PSW_MASK_BASE | PSW_MASK_EA | PSW_MASK_BA | PSW_MASK_WAIT; 33 quiesce_psw.addr = 0xfff; 34 __load_psw(quiesce_psw); 35} 36 37/* Handler for quiesce event. Start shutdown procedure. */ 38static void sclp_quiesce_handler(struct evbuf_header *evbuf) 39{ 40 if (_machine_restart != (void *) do_machine_quiesce) { 41 old_machine_restart = _machine_restart; 42 old_machine_halt = _machine_halt; 43 old_machine_power_off = _machine_power_off; 44 _machine_restart = (void *) do_machine_quiesce; 45 _machine_halt = do_machine_quiesce; 46 _machine_power_off = do_machine_quiesce; 47 } 48 ctrl_alt_del(); 49} 50 51/* Undo machine restart/halt/power_off modification on resume */ 52static void sclp_quiesce_pm_event(struct sclp_register *reg, 53 enum sclp_pm_event sclp_pm_event) 54{ 55 switch (sclp_pm_event) { 56 case SCLP_PM_EVENT_RESTORE: 57 if (old_machine_restart) { 58 _machine_restart = old_machine_restart; 59 _machine_halt = old_machine_halt; 60 _machine_power_off = old_machine_power_off; 61 old_machine_restart = NULL; 62 old_machine_halt = NULL; 63 old_machine_power_off = NULL; 64 } 65 break; 66 case SCLP_PM_EVENT_FREEZE: 67 case SCLP_PM_EVENT_THAW: 68 break; 69 } 70} 71 72static struct sclp_register sclp_quiesce_event = { 73 .receive_mask = EVTYP_SIGQUIESCE_MASK, 74 .receiver_fn = sclp_quiesce_handler, 75 .pm_event_fn = sclp_quiesce_pm_event 76}; 77 78/* Initialize quiesce driver. */ 79static int __init sclp_quiesce_init(void) 80{ 81 return sclp_register(&sclp_quiesce_event); 82} 83 84module_init(sclp_quiesce_init); 85