drivers/s390/char/sclp_quiesce.c

   1 /*
   2  *  drivers/s390/char/sclp_quiesce.c
   3  *     signal quiesce handler
   4  *
   5  *  (C) Copyright IBM Corp. 1999,2004
   6  *  Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   7  *             Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/types.h>
  12 #include <linux/cpumask.h>
  13 #include <linux/smp.h>
  14 #include <linux/init.h>
  15 #include <linux/reboot.h>
  16 #include <asm/atomic.h>
  17 #include <asm/ptrace.h>
  18 #include <asm/sigp.h>
  19
  20 #include "sclp.h"
  21
  22 /* Shutdown handler. Signal completion of shutdown by loading special PSW. */
  23 static void
  24 do_machine_quiesce(void)
  25 {
  26         psw_t quiesce_psw;
  27
  28         smp_send_stop();
  29         quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
  30         quiesce_psw.addr = 0xfff;
  31         __load_psw(quiesce_psw);
  32 }
  33
  34 /* Handler for quiesce event. Start shutdown procedure. */
  35 static void
  36 sclp_quiesce_handler(struct evbuf_header *evbuf)
  37 {
  38         _machine_restart = (void *) do_machine_quiesce;
  39         _machine_halt = do_machine_quiesce;
  40         _machine_power_off = do_machine_quiesce;
  41         ctrl_alt_del();
  42 }
  43
  44 static struct sclp_register sclp_quiesce_event = {
  45         .receive_mask = EvTyp_SigQuiesce_Mask,
  46         .receiver_fn = sclp_quiesce_handler
  47 };
  48
  49 /* Initialize quiesce driver. */
  50 static int __init
  51 sclp_quiesce_init(void)
  52 {
  53         int rc;
  54
  55         rc = sclp_register(&sclp_quiesce_event);
  56         if (rc)
  57                 printk(KERN_WARNING "sclp: could not register quiesce handler "
  58                        "(rc=%d)\n", rc);
  59         return rc;
  60 }
  61
  62 module_init(sclp_quiesce_init);