drivers/s390/char/sclp_config.c

   1 /*
   2  *    Copyright IBM Corp. 2007
   3  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
   4  */
   5
   6 #define KMSG_COMPONENT "sclp_config"
   7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
   8
   9 #include <linux/init.h>
  10 #include <linux/errno.h>
  11 #include <linux/cpu.h>
  12 #include <linux/device.h>
  13 #include <linux/workqueue.h>
  14 #include <asm/smp.h>
  15
  16 #include "sclp.h"
  17
  18 struct conf_mgm_data {
  19         u8 reserved;
  20         u8 ev_qualifier;
  21 } __attribute__((packed));
  22
  23 #define EV_QUAL_CPU_CHANGE      1
  24 #define EV_QUAL_CAP_CHANGE      3
  25
  26 static struct work_struct sclp_cpu_capability_work;
  27 static struct work_struct sclp_cpu_change_work;
  28
  29 static void sclp_cpu_capability_notify(struct work_struct *work)
  30 {
  31         int cpu;
  32         struct device *dev;
  33
  34         s390_adjust_jiffies();
  35         pr_info("CPU capability may have changed\n");
  36         get_online_cpus();
  37         for_each_online_cpu(cpu) {
  38                 dev = get_cpu_device(cpu);
  39                 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
  40         }
  41         put_online_cpus();
  42 }
  43
  44 static void __ref sclp_cpu_change_notify(struct work_struct *work)
  45 {
  46         lock_device_hotplug();
  47         smp_rescan_cpus();
  48         unlock_device_hotplug();
  49 }
  50
  51 static void sclp_conf_receiver_fn(struct evbuf_header *evbuf)
  52 {
  53         struct conf_mgm_data *cdata;
  54
  55         cdata = (struct conf_mgm_data *)(evbuf + 1);
  56         switch (cdata->ev_qualifier) {
  57         case EV_QUAL_CPU_CHANGE:
  58                 schedule_work(&sclp_cpu_change_work);
  59                 break;
  60         case EV_QUAL_CAP_CHANGE:
  61                 schedule_work(&sclp_cpu_capability_work);
  62                 break;
  63         }
  64 }
  65
  66 static struct sclp_register sclp_conf_register =
  67 {
  68         .receive_mask = EVTYP_CONFMGMDATA_MASK,
  69         .receiver_fn  = sclp_conf_receiver_fn,
  70 };
  71
  72 static int __init sclp_conf_init(void)
  73 {
  74         INIT_WORK(&sclp_cpu_capability_work, sclp_cpu_capability_notify);
  75         INIT_WORK(&sclp_cpu_change_work, sclp_cpu_change_notify);
  76         return sclp_register(&sclp_conf_register);
  77 }
  78
  79 __initcall(sclp_conf_init);