drivers/s390/char/sclp_config.c

   1 /*
   2  *  drivers/s390/char/sclp_config.c
   3  *
   4  *    Copyright IBM Corp. 2007
   5  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
   6  */
   7
   8 #define KMSG_COMPONENT "sclp_config"
   9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  10
  11 #include <linux/init.h>
  12 #include <linux/errno.h>
  13 #include <linux/cpu.h>
  14 #include <linux/sysdev.h>
  15 #include <linux/workqueue.h>
  16 #include <asm/smp.h>
  17
  18 #include "sclp.h"
  19
  20 struct conf_mgm_data {
  21         u8 reserved;
  22         u8 ev_qualifier;
  23 } __attribute__((packed));
  24
  25 #define EV_QUAL_CPU_CHANGE      1
  26 #define EV_QUAL_CAP_CHANGE      3
  27
  28 static struct work_struct sclp_cpu_capability_work;
  29 static struct work_struct sclp_cpu_change_work;
  30
  31 static void sclp_cpu_capability_notify(struct work_struct *work)
  32 {
  33         int cpu;
  34         struct sys_device *sysdev;
  35
  36         pr_warning("cpu capability changed.\n");
  37         get_online_cpus();
  38         for_each_online_cpu(cpu) {
  39                 sysdev = get_cpu_sysdev(cpu);
  40                 kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
  41         }
  42         put_online_cpus();
  43 }
  44
  45 static void __ref sclp_cpu_change_notify(struct work_struct *work)
  46 {
  47         smp_rescan_cpus();
  48 }
  49
  50 static void sclp_conf_receiver_fn(struct evbuf_header *evbuf)
  51 {
  52         struct conf_mgm_data *cdata;
  53
  54         cdata = (struct conf_mgm_data *)(evbuf + 1);
  55         switch (cdata->ev_qualifier) {
  56         case EV_QUAL_CPU_CHANGE:
  57                 schedule_work(&sclp_cpu_change_work);
  58                 break;
  59         case EV_QUAL_CAP_CHANGE:
  60                 schedule_work(&sclp_cpu_capability_work);
  61                 break;
  62         }
  63 }
  64
  65 static struct sclp_register sclp_conf_register =
  66 {
  67         .receive_mask = EVTYP_CONFMGMDATA_MASK,
  68         .receiver_fn  = sclp_conf_receiver_fn,
  69 };
  70
  71 static int __init sclp_conf_init(void)
  72 {
  73         int rc;
  74
  75         INIT_WORK(&sclp_cpu_capability_work, sclp_cpu_capability_notify);
  76         INIT_WORK(&sclp_cpu_change_work, sclp_cpu_change_notify);
  77
  78         rc = sclp_register(&sclp_conf_register);
  79         if (rc)
  80                 return rc;
  81
  82         if (!(sclp_conf_register.sclp_send_mask & EVTYP_CONFMGMDATA_MASK)) {
  83                 pr_warning("no configuration management.\n");
  84                 sclp_unregister(&sclp_conf_register);
  85                 rc = -ENOSYS;
  86         }
  87         return rc;
  88 }
  89
  90 __initcall(sclp_conf_init);