hw/s390x/sclpquiesce.c

   1 /*
   2  * SCLP event type
   3  *    Signal Quiesce - trigger system powerdown request
   4  *
   5  * Copyright IBM, Corp. 2012
   6  *
   7  * Authors:
   8  *  Heinz Graalfs <graalfs@de.ibm.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2 or (at your
  11  * option) any later version.  See the COPYING file in the top-level directory.
  12  *
  13  */
  14
  15 #include "qemu/osdep.h"
  16 #include "hw/s390x/sclp.h"
  17 #include "migration/vmstate.h"
  18 #include "qemu/module.h"
  19 #include "sysemu/runstate.h"
  20 #include "hw/s390x/event-facility.h"
  21
  22 typedef struct SignalQuiesce {
  23     EventBufferHeader ebh;
  24     uint16_t timeout;
  25     uint8_t unit;
  26 } QEMU_PACKED SignalQuiesce;
  27
  28 static bool can_handle_event(uint8_t type)
  29 {
  30     return type == SCLP_EVENT_SIGNAL_QUIESCE;
  31 }
  32
  33 static sccb_mask_t send_mask(void)
  34 {
  35     return SCLP_EVENT_MASK_SIGNAL_QUIESCE;
  36 }
  37
  38 static sccb_mask_t receive_mask(void)
  39 {
  40     return 0;
  41 }
  42
  43 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
  44                            int *slen)
  45 {
  46     SignalQuiesce *sq = (SignalQuiesce *) evt_buf_hdr;
  47
  48     if (*slen < sizeof(SignalQuiesce)) {
  49         return 0;
  50     }
  51
  52     if (!event->event_pending) {
  53         return 0;
  54     }
  55     event->event_pending = false;
  56
  57     sq->ebh.length = cpu_to_be16(sizeof(SignalQuiesce));
  58     sq->ebh.type = SCLP_EVENT_SIGNAL_QUIESCE;
  59     sq->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
  60     /*
  61      * system_powerdown does not have a timeout. Fortunately the
  62      * timeout value is currently ignored by Linux, anyway
  63      */
  64     sq->timeout = cpu_to_be16(0);
  65     sq->unit = cpu_to_be16(0);
  66     *slen -= sizeof(SignalQuiesce);
  67
  68     return 1;
  69 }
  70
  71 static const VMStateDescription vmstate_sclpquiesce = {
  72     .name = TYPE_SCLP_QUIESCE,
  73     .version_id = 0,
  74     .minimum_version_id = 0,
  75     .fields = (VMStateField[]) {
  76         VMSTATE_BOOL(event_pending, SCLPEvent),
  77         VMSTATE_END_OF_LIST()
  78      }
  79 };
  80
  81 typedef struct QuiesceNotifier QuiesceNotifier;
  82
  83 static struct QuiesceNotifier {
  84     Notifier notifier;
  85     SCLPEvent *event;
  86 } qn;
  87
  88 static void quiesce_powerdown_req(Notifier *n, void *opaque)
  89 {
  90     QuiesceNotifier *qn = container_of(n, QuiesceNotifier, notifier);
  91     SCLPEvent *event = qn->event;
  92
  93     event->event_pending = true;
  94     /* trigger SCLP read operation */
  95     sclp_service_interrupt(0);
  96 }
  97
  98 static int quiesce_init(SCLPEvent *event)
  99 {
 100     qn.notifier.notify = quiesce_powerdown_req;
 101     qn.event = event;
 102
 103     qemu_register_powerdown_notifier(&qn.notifier);
 104
 105     return 0;
 106 }
 107
 108 static void quiesce_reset(DeviceState *dev)
 109 {
 110    SCLPEvent *event = SCLP_EVENT(dev);
 111
 112    event->event_pending = false;
 113 }
 114
 115 static void quiesce_class_init(ObjectClass *klass, void *data)
 116 {
 117     DeviceClass *dc = DEVICE_CLASS(klass);
 118     SCLPEventClass *k = SCLP_EVENT_CLASS(klass);
 119
 120     dc->reset = quiesce_reset;
 121     dc->vmsd = &vmstate_sclpquiesce;
 122     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 123     /*
 124      * Reason: This is just an internal device - the notifier should
 125      * not be registered multiple times in quiesce_init()
 126      */
 127     dc->user_creatable = false;
 128
 129     k->init = quiesce_init;
 130     k->get_send_mask = send_mask;
 131     k->get_receive_mask = receive_mask;
 132     k->can_handle_event = can_handle_event;
 133     k->read_event_data = read_event_data;
 134     k->write_event_data = NULL;
 135 }
 136
 137 static const TypeInfo sclp_quiesce_info = {
 138     .name          = TYPE_SCLP_QUIESCE,
 139     .parent        = TYPE_SCLP_EVENT,
 140     .instance_size = sizeof(SCLPEvent),
 141     .class_init    = quiesce_class_init,
 142     .class_size    = sizeof(SCLPEventClass),
 143 };
 144
 145 static void register_types(void)
 146 {
 147     type_register_static(&sclp_quiesce_info);
 148 }
 149
 150 type_init(register_types)