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 "qemu/osdep.h" 19 #include "sysemu/sysemu.h" 20 21 #include "hw/s390x/sclp.h" 22 #include "hw/s390x/event-facility.h" 23 24 typedef struct SCLPEventsBus { 25 BusState qbus; 26 } SCLPEventsBus; 27 28 struct SCLPEventFacility { 29 SysBusDevice parent_obj; 30 SCLPEventsBus sbus; 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 rc = SCLP_RC_INVALID_FUNCTION; 116 117 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 118 DeviceState *qdev = kid->child; 119 event = (SCLPEvent *) qdev; 120 ec = SCLP_EVENT_GET_CLASS(event); 121 122 if (ec->write_event_data && 123 ec->can_handle_event(event_buf->type)) { 124 rc = ec->write_event_data(event, event_buf); 125 break; 126 } 127 } 128 return rc; 129 } 130 131 static uint16_t handle_sccb_write_events(SCLPEventFacility *ef, SCCB *sccb) 132 { 133 uint16_t rc; 134 int slen; 135 unsigned elen = 0; 136 EventBufferHeader *event_buf; 137 WriteEventData *wed = (WriteEventData *) sccb; 138 139 event_buf = &wed->ebh; 140 rc = SCLP_RC_NORMAL_COMPLETION; 141 142 /* loop over all contained event buffers */ 143 for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) { 144 elen = be16_to_cpu(event_buf->length); 145 146 /* in case of a previous error mark all trailing buffers 147 * as not accepted */ 148 if (rc != SCLP_RC_NORMAL_COMPLETION) { 149 event_buf->flags &= ~(SCLP_EVENT_BUFFER_ACCEPTED); 150 } else { 151 rc = handle_write_event_buf(ef, event_buf, sccb); 152 } 153 event_buf = (void *) event_buf + elen; 154 } 155 return rc; 156 } 157 158 static void write_event_data(SCLPEventFacility *ef, SCCB *sccb) 159 { 160 if (sccb->h.function_code != SCLP_FC_NORMAL_WRITE) { 161 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION); 162 goto out; 163 } 164 if (be16_to_cpu(sccb->h.length) < 8) { 165 sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); 166 goto out; 167 } 168 /* first do a sanity check of the write events */ 169 sccb->h.response_code = cpu_to_be16(write_event_length_check(sccb)); 170 171 /* if no early error, then execute */ 172 if (sccb->h.response_code == be16_to_cpu(SCLP_RC_NORMAL_COMPLETION)) { 173 sccb->h.response_code = 174 cpu_to_be16(handle_sccb_write_events(ef, sccb)); 175 } 176 177 out: 178 return; 179 } 180 181 static uint16_t handle_sccb_read_events(SCLPEventFacility *ef, SCCB *sccb, 182 unsigned int mask) 183 { 184 uint16_t rc; 185 int slen; 186 unsigned elen; 187 BusChild *kid; 188 SCLPEvent *event; 189 SCLPEventClass *ec; 190 EventBufferHeader *event_buf; 191 ReadEventData *red = (ReadEventData *) sccb; 192 193 event_buf = &red->ebh; 194 event_buf->length = 0; 195 slen = sizeof(sccb->data); 196 197 rc = SCLP_RC_NO_EVENT_BUFFERS_STORED; 198 199 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 200 DeviceState *qdev = kid->child; 201 event = (SCLPEvent *) qdev; 202 ec = SCLP_EVENT_GET_CLASS(event); 203 204 if (mask & ec->get_send_mask()) { 205 if (ec->read_event_data(event, event_buf, &slen)) { 206 elen = be16_to_cpu(event_buf->length); 207 event_buf = (EventBufferHeader *) ((char *)event_buf + elen); 208 rc = SCLP_RC_NORMAL_COMPLETION; 209 } 210 } 211 } 212 213 if (sccb->h.control_mask[2] & SCLP_VARIABLE_LENGTH_RESPONSE) { 214 /* architecture suggests to reset variable-length-response bit */ 215 sccb->h.control_mask[2] &= ~SCLP_VARIABLE_LENGTH_RESPONSE; 216 /* with a new length value */ 217 sccb->h.length = cpu_to_be16(SCCB_SIZE - slen); 218 } 219 return rc; 220 } 221 222 static void read_event_data(SCLPEventFacility *ef, SCCB *sccb) 223 { 224 unsigned int sclp_active_selection_mask; 225 unsigned int sclp_cp_receive_mask; 226 227 ReadEventData *red = (ReadEventData *) sccb; 228 229 if (be16_to_cpu(sccb->h.length) != SCCB_SIZE) { 230 sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); 231 goto out; 232 } 233 234 sclp_cp_receive_mask = ef->receive_mask; 235 236 /* get active selection mask */ 237 switch (sccb->h.function_code) { 238 case SCLP_UNCONDITIONAL_READ: 239 sclp_active_selection_mask = sclp_cp_receive_mask; 240 break; 241 case SCLP_SELECTIVE_READ: 242 sclp_active_selection_mask = be32_to_cpu(red->mask); 243 if (!sclp_cp_receive_mask || 244 (sclp_active_selection_mask & ~sclp_cp_receive_mask)) { 245 sccb->h.response_code = 246 cpu_to_be16(SCLP_RC_INVALID_SELECTION_MASK); 247 goto out; 248 } 249 break; 250 default: 251 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION); 252 goto out; 253 } 254 sccb->h.response_code = cpu_to_be16( 255 handle_sccb_read_events(ef, sccb, sclp_active_selection_mask)); 256 257 out: 258 return; 259 } 260 261 static void write_event_mask(SCLPEventFacility *ef, SCCB *sccb) 262 { 263 WriteEventMask *we_mask = (WriteEventMask *) sccb; 264 265 /* Attention: We assume that Linux uses 4-byte masks, what it actually 266 does. Architecture allows for masks of variable size, though */ 267 if (be16_to_cpu(we_mask->mask_length) != 4) { 268 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_MASK_LENGTH); 269 goto out; 270 } 271 272 /* keep track of the guest's capability masks */ 273 ef->receive_mask = be32_to_cpu(we_mask->cp_receive_mask); 274 275 /* return the SCLP's capability masks to the guest */ 276 we_mask->send_mask = cpu_to_be32(get_host_send_mask(ef)); 277 we_mask->receive_mask = cpu_to_be32(get_host_receive_mask(ef)); 278 279 sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_COMPLETION); 280 281 out: 282 return; 283 } 284 285 /* qemu object creation and initialization functions */ 286 287 #define TYPE_SCLP_EVENTS_BUS "s390-sclp-events-bus" 288 289 static void sclp_events_bus_realize(BusState *bus, Error **errp) 290 { 291 BusChild *kid; 292 293 /* TODO: recursive realization has to be done in common code */ 294 QTAILQ_FOREACH(kid, &bus->children, sibling) { 295 DeviceState *dev = kid->child; 296 297 object_property_set_bool(OBJECT(dev), true, "realized", errp); 298 if (*errp) { 299 return; 300 } 301 } 302 } 303 304 static void sclp_events_bus_class_init(ObjectClass *klass, void *data) 305 { 306 BusClass *bc = BUS_CLASS(klass); 307 308 bc->realize = sclp_events_bus_realize; 309 } 310 311 static const TypeInfo sclp_events_bus_info = { 312 .name = TYPE_SCLP_EVENTS_BUS, 313 .parent = TYPE_BUS, 314 .class_init = sclp_events_bus_class_init, 315 }; 316 317 static void command_handler(SCLPEventFacility *ef, SCCB *sccb, uint64_t code) 318 { 319 switch (code & SCLP_CMD_CODE_MASK) { 320 case SCLP_CMD_READ_EVENT_DATA: 321 read_event_data(ef, sccb); 322 break; 323 case SCLP_CMD_WRITE_EVENT_DATA: 324 write_event_data(ef, sccb); 325 break; 326 case SCLP_CMD_WRITE_EVENT_MASK: 327 write_event_mask(ef, sccb); 328 break; 329 default: 330 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND); 331 break; 332 } 333 } 334 335 static const VMStateDescription vmstate_event_facility = { 336 .name = "vmstate-event-facility", 337 .version_id = 0, 338 .minimum_version_id = 0, 339 .fields = (VMStateField[]) { 340 VMSTATE_UINT32(receive_mask, SCLPEventFacility), 341 VMSTATE_END_OF_LIST() 342 } 343 }; 344 345 static void init_event_facility(Object *obj) 346 { 347 SCLPEventFacility *event_facility = EVENT_FACILITY(obj); 348 DeviceState *sdev = DEVICE(obj); 349 Object *new; 350 351 /* Spawn a new bus for SCLP events */ 352 qbus_create_inplace(&event_facility->sbus, sizeof(event_facility->sbus), 353 TYPE_SCLP_EVENTS_BUS, sdev, NULL); 354 355 new = object_new(TYPE_SCLP_QUIESCE); 356 object_property_add_child(obj, TYPE_SCLP_QUIESCE, new, NULL); 357 object_unref(new); 358 qdev_set_parent_bus(DEVICE(new), &event_facility->sbus.qbus); 359 360 new = object_new(TYPE_SCLP_CPU_HOTPLUG); 361 object_property_add_child(obj, TYPE_SCLP_CPU_HOTPLUG, new, NULL); 362 object_unref(new); 363 qdev_set_parent_bus(DEVICE(new), &event_facility->sbus.qbus); 364 /* the facility will automatically realize the devices via the bus */ 365 } 366 367 static void reset_event_facility(DeviceState *dev) 368 { 369 SCLPEventFacility *sdev = EVENT_FACILITY(dev); 370 371 sdev->receive_mask = 0; 372 } 373 374 static void init_event_facility_class(ObjectClass *klass, void *data) 375 { 376 SysBusDeviceClass *sbdc = SYS_BUS_DEVICE_CLASS(klass); 377 DeviceClass *dc = DEVICE_CLASS(sbdc); 378 SCLPEventFacilityClass *k = EVENT_FACILITY_CLASS(dc); 379 380 dc->reset = reset_event_facility; 381 dc->vmsd = &vmstate_event_facility; 382 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 383 k->command_handler = command_handler; 384 k->event_pending = event_pending; 385 } 386 387 static const TypeInfo sclp_event_facility_info = { 388 .name = TYPE_SCLP_EVENT_FACILITY, 389 .parent = TYPE_SYS_BUS_DEVICE, 390 .instance_init = init_event_facility, 391 .instance_size = sizeof(SCLPEventFacility), 392 .class_init = init_event_facility_class, 393 .class_size = sizeof(SCLPEventFacilityClass), 394 }; 395 396 static void event_realize(DeviceState *qdev, Error **errp) 397 { 398 SCLPEvent *event = SCLP_EVENT(qdev); 399 SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event); 400 401 if (child->init) { 402 int rc = child->init(event); 403 if (rc < 0) { 404 error_setg(errp, "SCLP event initialization failed."); 405 return; 406 } 407 } 408 } 409 410 static void event_unrealize(DeviceState *qdev, Error **errp) 411 { 412 SCLPEvent *event = SCLP_EVENT(qdev); 413 SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event); 414 if (child->exit) { 415 int rc = child->exit(event); 416 if (rc < 0) { 417 error_setg(errp, "SCLP event exit failed."); 418 return; 419 } 420 } 421 } 422 423 static void event_class_init(ObjectClass *klass, void *data) 424 { 425 DeviceClass *dc = DEVICE_CLASS(klass); 426 427 dc->bus_type = TYPE_SCLP_EVENTS_BUS; 428 dc->realize = event_realize; 429 dc->unrealize = event_unrealize; 430 } 431 432 static const TypeInfo sclp_event_type_info = { 433 .name = TYPE_SCLP_EVENT, 434 .parent = TYPE_DEVICE, 435 .instance_size = sizeof(SCLPEvent), 436 .class_init = event_class_init, 437 .class_size = sizeof(SCLPEventClass), 438 .abstract = true, 439 }; 440 441 static void register_types(void) 442 { 443 type_register_static(&sclp_events_bus_info); 444 type_register_static(&sclp_event_facility_info); 445 type_register_static(&sclp_event_type_info); 446 } 447 448 type_init(register_types) 449