hw/s390x/event-facility.c

   1 /*
   2  * SCLP
   3  *    Event Facility
   4  *       handles SCLP event types
   5  *          - Signal Quiesce - system power down
   6  *          - ASCII Console Data - VT220 read and write
   7  *
   8  * Copyright IBM, Corp. 2012
   9  *
  10  * Authors:
  11  *  Heinz Graalfs <graalfs@de.ibm.com>
  12  *
  13  * This work is licensed under the terms of the GNU GPL, version 2 or (at your
  14  * option) any later version.  See the COPYING file in the top-level directory.
  15  *
  16  */
  17
  18 #include "monitor.h"
  19 #include "sysemu.h"
  20
  21 #include "sclp.h"
  22 #include "event-facility.h"
  23
  24 typedef struct EventTypesBus {
  25     BusState qbus;
  26 } EventTypesBus;
  27
  28 struct SCLPEventFacility {
  29     EventTypesBus sbus;
  30     DeviceState *qdev;
  31     /* guest' receive mask */
  32     unsigned int receive_mask;
  33 };
  34
  35 /* return true if any child has event pending set */
  36 static bool event_pending(SCLPEventFacility *ef)
  37 {
  38     BusChild *kid;
  39     SCLPEvent *event;
  40     SCLPEventClass *event_class;
  41
  42     QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
  43         DeviceState *qdev = kid->child;
  44         event = DO_UPCAST(SCLPEvent, qdev, qdev);
  45         event_class = SCLP_EVENT_GET_CLASS(event);
  46         if (event->event_pending &&
  47             event_class->get_send_mask() & ef->receive_mask) {
  48             return true;
  49         }
  50     }
  51     return false;
  52 }
  53
  54 static unsigned int get_host_send_mask(SCLPEventFacility *ef)
  55 {
  56     unsigned int mask;
  57     BusChild *kid;
  58     SCLPEventClass *child;
  59
  60     mask = 0;
  61
  62     QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
  63         DeviceState *qdev = kid->child;
  64         child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev);
  65         mask |= child->get_send_mask();
  66     }
  67     return mask;
  68 }
  69
  70 static unsigned int get_host_receive_mask(SCLPEventFacility *ef)
  71 {
  72     unsigned int mask;
  73     BusChild *kid;
  74     SCLPEventClass *child;
  75
  76     mask = 0;
  77
  78     QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
  79         DeviceState *qdev = kid->child;
  80         child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev);
  81         mask |= child->get_receive_mask();
  82     }
  83     return mask;
  84 }
  85
  86 static uint16_t write_event_length_check(SCCB *sccb)
  87 {
  88     int slen;
  89     unsigned elen = 0;
  90     EventBufferHeader *event;
  91     WriteEventData *wed = (WriteEventData *) sccb;
  92
  93     event = (EventBufferHeader *) &wed->ebh;
  94     for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) {
  95         elen = be16_to_cpu(event->length);
  96         if (elen < sizeof(*event) || elen > slen) {
  97             return SCLP_RC_EVENT_BUFFER_SYNTAX_ERROR;
  98         }
  99         event = (void *) event + elen;
 100     }
 101     if (slen) {
 102         return SCLP_RC_INCONSISTENT_LENGTHS;
 103     }
 104     return SCLP_RC_NORMAL_COMPLETION;
 105 }
 106
 107 static uint16_t handle_write_event_buf(SCLPEventFacility *ef,
 108                                        EventBufferHeader *event_buf, SCCB *sccb)
 109 {
 110     uint16_t rc;
 111     BusChild *kid;
 112     SCLPEvent *event;
 113     SCLPEventClass *ec;
 114
 115     QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
 116         DeviceState *qdev = kid->child;
 117         event = (SCLPEvent *) qdev;
 118         ec = SCLP_EVENT_GET_CLASS(event);
 119
 120         rc = SCLP_RC_INVALID_FUNCTION;
 121         if (ec->write_event_data &&
 122             ec->event_type() == event_buf->type) {
 123             rc = ec->write_event_data(event, event_buf);
 124             break;
 125         }
 126     }
 127     return rc;
 128 }
 129
 130 static uint16_t handle_sccb_write_events(SCLPEventFacility *ef, SCCB *sccb)
 131 {
 132     uint16_t rc;
 133     int slen;
 134     unsigned elen = 0;
 135     EventBufferHeader *event_buf;
 136     WriteEventData *wed = (WriteEventData *) sccb;
 137
 138     event_buf = &wed->ebh;
 139     rc = SCLP_RC_NORMAL_COMPLETION;
 140
 141     /* loop over all contained event buffers */
 142     for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) {
 143         elen = be16_to_cpu(event_buf->length);
 144
 145         /* in case of a previous error mark all trailing buffers
 146          * as not accepted */
 147         if (rc != SCLP_RC_NORMAL_COMPLETION) {
 148             event_buf->flags &= ~(SCLP_EVENT_BUFFER_ACCEPTED);
 149         } else {
 150             rc = handle_write_event_buf(ef, event_buf, sccb);
 151         }
 152         event_buf = (void *) event_buf + elen;
 153     }
 154     return rc;
 155 }
 156
 157 static void write_event_data(SCLPEventFacility *ef, SCCB *sccb)
 158 {
 159     if (sccb->h.function_code != SCLP_FC_NORMAL_WRITE) {
 160         sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION);
 161         goto out;
 162     }
 163     if (be16_to_cpu(sccb->h.length) < 8) {
 164         sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
 165         goto out;
 166     }
 167     /* first do a sanity check of the write events */
 168     sccb->h.response_code = cpu_to_be16(write_event_length_check(sccb));
 169
 170     /* if no early error, then execute */
 171     if (sccb->h.response_code == be16_to_cpu(SCLP_RC_NORMAL_COMPLETION)) {
 172         sccb->h.response_code =
 173                 cpu_to_be16(handle_sccb_write_events(ef, sccb));
 174     }
 175
 176 out:
 177     return;
 178 }
 179
 180 static uint16_t handle_sccb_read_events(SCLPEventFacility *ef, SCCB *sccb,
 181                                         unsigned int mask)
 182 {
 183     uint16_t rc;
 184     int slen;
 185     unsigned elen = 0;
 186     BusChild *kid;
 187     SCLPEvent *event;
 188     SCLPEventClass *ec;
 189     EventBufferHeader *event_buf;
 190     ReadEventData *red = (ReadEventData *) sccb;
 191
 192     event_buf = &red->ebh;
 193     event_buf->length = 0;
 194     slen = sizeof(sccb->data);
 195
 196     rc = SCLP_RC_NO_EVENT_BUFFERS_STORED;
 197
 198     QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) {
 199         DeviceState *qdev = kid->child;
 200         event = (SCLPEvent *) qdev;
 201         ec = SCLP_EVENT_GET_CLASS(event);
 202
 203         if (mask & ec->get_send_mask()) {
 204             if (ec->read_event_data(event, event_buf, &slen)) {
 205                 rc = SCLP_RC_NORMAL_COMPLETION;
 206             }
 207         }
 208         elen = be16_to_cpu(event_buf->length);
 209         event_buf = (void *) event_buf + elen;
 210     }
 211
 212     if (sccb->h.control_mask[2] & SCLP_VARIABLE_LENGTH_RESPONSE) {
 213         /* architecture suggests to reset variable-length-response bit */
 214         sccb->h.control_mask[2] &= ~SCLP_VARIABLE_LENGTH_RESPONSE;
 215         /* with a new length value */
 216         sccb->h.length = cpu_to_be16(SCCB_SIZE - slen);
 217     }
 218     return rc;
 219 }
 220
 221 static void read_event_data(SCLPEventFacility *ef, SCCB *sccb)
 222 {
 223     unsigned int sclp_active_selection_mask;
 224     unsigned int sclp_cp_receive_mask;
 225
 226     ReadEventData *red = (ReadEventData *) sccb;
 227
 228     if (be16_to_cpu(sccb->h.length) != SCCB_SIZE) {
 229         sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
 230         goto out;
 231     }
 232
 233     sclp_cp_receive_mask = ef->receive_mask;
 234
 235     /* get active selection mask */
 236     switch (sccb->h.function_code) {
 237     case SCLP_UNCONDITIONAL_READ:
 238         sclp_active_selection_mask = sclp_cp_receive_mask;
 239         break;
 240     case SCLP_SELECTIVE_READ:
 241         if (!(sclp_cp_receive_mask & be32_to_cpu(red->mask))) {
 242             sccb->h.response_code =
 243                     cpu_to_be16(SCLP_RC_INVALID_SELECTION_MASK);
 244             goto out;
 245         }
 246         sclp_active_selection_mask = be32_to_cpu(red->mask);
 247         break;
 248     default:
 249         sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION);
 250         goto out;
 251     }
 252     sccb->h.response_code = cpu_to_be16(
 253             handle_sccb_read_events(ef, sccb, sclp_active_selection_mask));
 254
 255 out:
 256     return;
 257 }
 258
 259 static void write_event_mask(SCLPEventFacility *ef, SCCB *sccb)
 260 {
 261     WriteEventMask *we_mask = (WriteEventMask *) sccb;
 262
 263     /* Attention: We assume that Linux uses 4-byte masks, what it actually
 264        does. Architecture allows for masks of variable size, though */
 265     if (be16_to_cpu(we_mask->mask_length) != 4) {
 266         sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_MASK_LENGTH);
 267         goto out;
 268     }
 269
 270     /* keep track of the guest's capability masks */
 271     ef->receive_mask = be32_to_cpu(we_mask->cp_receive_mask);
 272
 273     /* return the SCLP's capability masks to the guest */
 274     we_mask->send_mask = cpu_to_be32(get_host_send_mask(ef));
 275     we_mask->receive_mask = cpu_to_be32(get_host_receive_mask(ef));
 276
 277     sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_COMPLETION);
 278
 279 out:
 280     return;
 281 }
 282
 283 /* qemu object creation and initialization functions */
 284
 285 #define TYPE_SCLP_EVENTS_BUS "s390-sclp-events-bus"
 286
 287 static void sclp_events_bus_class_init(ObjectClass *klass, void *data)
 288 {
 289 }
 290
 291 static const TypeInfo s390_sclp_events_bus_info = {
 292     .name = TYPE_SCLP_EVENTS_BUS,
 293     .parent = TYPE_BUS,
 294     .class_init = sclp_events_bus_class_init,
 295 };
 296
 297 static void command_handler(SCLPEventFacility *ef, SCCB *sccb, uint64_t code)
 298 {
 299     switch (code) {
 300     case SCLP_CMD_READ_EVENT_DATA:
 301         read_event_data(ef, sccb);
 302         break;
 303     case SCLP_CMD_WRITE_EVENT_DATA:
 304         write_event_data(ef, sccb);
 305         break;
 306     case SCLP_CMD_WRITE_EVENT_MASK:
 307         write_event_mask(ef, sccb);
 308         break;
 309     default:
 310         sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND);
 311         break;
 312     }
 313 }
 314
 315 static int init_event_facility(S390SCLPDevice *sdev)
 316 {
 317     SCLPEventFacility *event_facility;
 318
 319     event_facility = g_malloc0(sizeof(SCLPEventFacility));
 320     sdev->ef = event_facility;
 321     sdev->sclp_command_handler = command_handler;
 322     sdev->event_pending = event_pending;
 323
 324     /* Spawn a new sclp-events facility */
 325     qbus_create_inplace(&event_facility->sbus.qbus,
 326                         TYPE_SCLP_EVENTS_BUS, (DeviceState *)sdev, NULL);
 327     event_facility->sbus.qbus.allow_hotplug = 0;
 328     event_facility->qdev = (DeviceState *) sdev;
 329
 330     return 0;
 331 }
 332
 333 static void init_event_facility_class(ObjectClass *klass, void *data)
 334 {
 335     S390SCLPDeviceClass *k = SCLP_S390_DEVICE_CLASS(klass);
 336
 337     k->init = init_event_facility;
 338 }
 339
 340 static TypeInfo s390_sclp_event_facility_info = {
 341     .name          = "s390-sclp-event-facility",
 342     .parent        = TYPE_DEVICE_S390_SCLP,
 343     .instance_size = sizeof(S390SCLPDevice),
 344     .class_init    = init_event_facility_class,
 345 };
 346
 347 static int event_qdev_init(DeviceState *qdev)
 348 {
 349     SCLPEvent *event = DO_UPCAST(SCLPEvent, qdev, qdev);
 350     SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event);
 351
 352     return child->init(event);
 353 }
 354
 355 static int event_qdev_exit(DeviceState *qdev)
 356 {
 357     SCLPEvent *event = DO_UPCAST(SCLPEvent, qdev, qdev);
 358     SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event);
 359     if (child->exit) {
 360         child->exit(event);
 361     }
 362     return 0;
 363 }
 364
 365 static void event_class_init(ObjectClass *klass, void *data)
 366 {
 367     DeviceClass *dc = DEVICE_CLASS(klass);
 368
 369     dc->bus_type = TYPE_SCLP_EVENTS_BUS;
 370     dc->unplug = qdev_simple_unplug_cb;
 371     dc->init = event_qdev_init;
 372     dc->exit = event_qdev_exit;
 373 }
 374
 375 static TypeInfo s390_sclp_event_type_info = {
 376     .name = TYPE_SCLP_EVENT,
 377     .parent = TYPE_DEVICE,
 378     .instance_size = sizeof(SCLPEvent),
 379     .class_init = event_class_init,
 380     .class_size = sizeof(SCLPEventClass),
 381     .abstract = true,
 382 };
 383
 384 static void register_types(void)
 385 {
 386     type_register_static(&s390_sclp_events_bus_info);
 387     type_register_static(&s390_sclp_event_facility_info);
 388     type_register_static(&s390_sclp_event_type_info);
 389 }
 390
 391 type_init(register_types)