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