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 #include <linux/init.h>
   9 #include <linux/errno.h>
  10 #include <linux/cpu.h>
  11 #include <linux/sysdev.h>
  12 #include <linux/workqueue.h>
  13 #include "sclp.h"
  14
  15 #define TAG     "sclp_config: "
  16
  17 struct conf_mgm_data {
  18         u8 reserved;
  19         u8 ev_qualifier;
  20 } __attribute__((packed));
  21
  22 #define EV_QUAL_CAP_CHANGE      3
  23
  24 static struct work_struct sclp_cpu_capability_work;
  25
  26 static void sclp_cpu_capability_notify(struct work_struct *work)
  27 {
  28         int cpu;
  29         struct sys_device *sysdev;
  30
  31         printk(KERN_WARNING TAG "cpu capability changed.\n");
  32         lock_cpu_hotplug();
  33         for_each_online_cpu(cpu) {
  34                 sysdev = get_cpu_sysdev(cpu);
  35                 kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
  36         }
  37         unlock_cpu_hotplug();
  38 }
  39
  40 static void sclp_conf_receiver_fn(struct evbuf_header *evbuf)
  41 {
  42         struct conf_mgm_data *cdata;
  43
  44         cdata = (struct conf_mgm_data *)(evbuf + 1);
  45         if (cdata->ev_qualifier == EV_QUAL_CAP_CHANGE)
  46                 schedule_work(&sclp_cpu_capability_work);
  47 }
  48
  49 static struct sclp_register sclp_conf_register =
  50 {
  51         .receive_mask = EVTYP_CONFMGMDATA_MASK,
  52         .receiver_fn  = sclp_conf_receiver_fn,
  53 };
  54
  55 static int __init sclp_conf_init(void)
  56 {
  57         int rc;
  58
  59         INIT_WORK(&sclp_cpu_capability_work, sclp_cpu_capability_notify);
  60
  61         rc = sclp_register(&sclp_conf_register);
  62         if (rc) {
  63                 printk(KERN_ERR TAG "failed to register (%d).\n", rc);
  64                 return rc;
  65         }
  66
  67         if (!(sclp_conf_register.sclp_receive_mask & EVTYP_CONFMGMDATA_MASK)) {
  68                 printk(KERN_WARNING TAG "no configuration management.\n");
  69                 sclp_unregister(&sclp_conf_register);
  70                 rc = -ENOSYS;
  71         }
  72         return rc;
  73 }
  74
  75 __initcall(sclp_conf_init);