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 "qapi/error.h" 20 #include "qemu/module.h" 21 #include "sysemu/sysemu.h" 22 23 #include "hw/s390x/sclp.h" 24 #include "migration/vmstate.h" 25 #include "hw/s390x/event-facility.h" 26 27 typedef struct SCLPEventsBus { 28 BusState qbus; 29 } SCLPEventsBus; 30 31 /* we need to save 32 bit chunks for compatibility */ 32 #ifdef HOST_WORDS_BIGENDIAN 33 #define RECV_MASK_LOWER 1 34 #define RECV_MASK_UPPER 0 35 #else /* little endian host */ 36 #define RECV_MASK_LOWER 0 37 #define RECV_MASK_UPPER 1 38 #endif 39 40 struct SCLPEventFacility { 41 SysBusDevice parent_obj; 42 SCLPEventsBus sbus; 43 /* guest's receive mask */ 44 union { 45 uint32_t receive_mask_pieces[2]; 46 sccb_mask_t receive_mask; 47 }; 48 /* 49 * when false, we keep the same broken, backwards compatible behaviour as 50 * before, allowing only masks of size exactly 4; when true, we implement 51 * the architecture correctly, allowing all valid mask sizes. Needed for 52 * migration toward older versions. 53 */ 54 bool allow_all_mask_sizes; 55 /* length of the receive mask */ 56 uint16_t mask_length; 57 }; 58 59 /* return true if any child has event pending set */ 60 static bool event_pending(SCLPEventFacility *ef) 61 { 62 BusChild *kid; 63 SCLPEvent *event; 64 SCLPEventClass *event_class; 65 66 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 67 DeviceState *qdev = kid->child; 68 event = DO_UPCAST(SCLPEvent, qdev, qdev); 69 event_class = SCLP_EVENT_GET_CLASS(event); 70 if (event->event_pending && 71 event_class->get_send_mask() & ef->receive_mask) { 72 return true; 73 } 74 } 75 return false; 76 } 77 78 static sccb_mask_t get_host_send_mask(SCLPEventFacility *ef) 79 { 80 sccb_mask_t mask; 81 BusChild *kid; 82 SCLPEventClass *child; 83 84 mask = 0; 85 86 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 87 DeviceState *qdev = kid->child; 88 child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev); 89 mask |= child->get_send_mask(); 90 } 91 return mask; 92 } 93 94 static sccb_mask_t get_host_receive_mask(SCLPEventFacility *ef) 95 { 96 sccb_mask_t mask; 97 BusChild *kid; 98 SCLPEventClass *child; 99 100 mask = 0; 101 102 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 103 DeviceState *qdev = kid->child; 104 child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev); 105 mask |= child->get_receive_mask(); 106 } 107 return mask; 108 } 109 110 static uint16_t write_event_length_check(SCCB *sccb) 111 { 112 int slen; 113 unsigned elen = 0; 114 EventBufferHeader *event; 115 WriteEventData *wed = (WriteEventData *) sccb; 116 117 event = (EventBufferHeader *) &wed->ebh; 118 for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) { 119 elen = be16_to_cpu(event->length); 120 if (elen < sizeof(*event) || elen > slen) { 121 return SCLP_RC_EVENT_BUFFER_SYNTAX_ERROR; 122 } 123 event = (void *) event + elen; 124 } 125 if (slen) { 126 return SCLP_RC_INCONSISTENT_LENGTHS; 127 } 128 return SCLP_RC_NORMAL_COMPLETION; 129 } 130 131 static uint16_t handle_write_event_buf(SCLPEventFacility *ef, 132 EventBufferHeader *event_buf, SCCB *sccb) 133 { 134 uint16_t rc; 135 BusChild *kid; 136 SCLPEvent *event; 137 SCLPEventClass *ec; 138 139 rc = SCLP_RC_INVALID_FUNCTION; 140 141 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 142 DeviceState *qdev = kid->child; 143 event = (SCLPEvent *) qdev; 144 ec = SCLP_EVENT_GET_CLASS(event); 145 146 if (ec->write_event_data && 147 ec->can_handle_event(event_buf->type)) { 148 rc = ec->write_event_data(event, event_buf); 149 break; 150 } 151 } 152 return rc; 153 } 154 155 static uint16_t handle_sccb_write_events(SCLPEventFacility *ef, SCCB *sccb) 156 { 157 uint16_t rc; 158 int slen; 159 unsigned elen = 0; 160 EventBufferHeader *event_buf; 161 WriteEventData *wed = (WriteEventData *) sccb; 162 163 event_buf = &wed->ebh; 164 rc = SCLP_RC_NORMAL_COMPLETION; 165 166 /* loop over all contained event buffers */ 167 for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) { 168 elen = be16_to_cpu(event_buf->length); 169 170 /* in case of a previous error mark all trailing buffers 171 * as not accepted */ 172 if (rc != SCLP_RC_NORMAL_COMPLETION) { 173 event_buf->flags &= ~(SCLP_EVENT_BUFFER_ACCEPTED); 174 } else { 175 rc = handle_write_event_buf(ef, event_buf, sccb); 176 } 177 event_buf = (void *) event_buf + elen; 178 } 179 return rc; 180 } 181 182 static void write_event_data(SCLPEventFacility *ef, SCCB *sccb) 183 { 184 if (sccb->h.function_code != SCLP_FC_NORMAL_WRITE) { 185 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION); 186 goto out; 187 } 188 if (be16_to_cpu(sccb->h.length) < 8) { 189 sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); 190 goto out; 191 } 192 /* first do a sanity check of the write events */ 193 sccb->h.response_code = cpu_to_be16(write_event_length_check(sccb)); 194 195 /* if no early error, then execute */ 196 if (sccb->h.response_code == be16_to_cpu(SCLP_RC_NORMAL_COMPLETION)) { 197 sccb->h.response_code = 198 cpu_to_be16(handle_sccb_write_events(ef, sccb)); 199 } 200 201 out: 202 return; 203 } 204 205 static uint16_t handle_sccb_read_events(SCLPEventFacility *ef, SCCB *sccb, 206 sccb_mask_t mask) 207 { 208 uint16_t rc; 209 int slen; 210 unsigned elen; 211 BusChild *kid; 212 SCLPEvent *event; 213 SCLPEventClass *ec; 214 EventBufferHeader *event_buf; 215 ReadEventData *red = (ReadEventData *) sccb; 216 217 event_buf = &red->ebh; 218 event_buf->length = 0; 219 slen = sizeof(sccb->data); 220 221 rc = SCLP_RC_NO_EVENT_BUFFERS_STORED; 222 223 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 224 DeviceState *qdev = kid->child; 225 event = (SCLPEvent *) qdev; 226 ec = SCLP_EVENT_GET_CLASS(event); 227 228 if (mask & ec->get_send_mask()) { 229 if (ec->read_event_data(event, event_buf, &slen)) { 230 elen = be16_to_cpu(event_buf->length); 231 event_buf = (EventBufferHeader *) ((char *)event_buf + elen); 232 rc = SCLP_RC_NORMAL_COMPLETION; 233 } 234 } 235 } 236 237 if (sccb->h.control_mask[2] & SCLP_VARIABLE_LENGTH_RESPONSE) { 238 /* architecture suggests to reset variable-length-response bit */ 239 sccb->h.control_mask[2] &= ~SCLP_VARIABLE_LENGTH_RESPONSE; 240 /* with a new length value */ 241 sccb->h.length = cpu_to_be16(SCCB_SIZE - slen); 242 } 243 return rc; 244 } 245 246 /* copy up to src_len bytes and fill the rest of dst with zeroes */ 247 static void copy_mask(uint8_t *dst, uint8_t *src, uint16_t dst_len, 248 uint16_t src_len) 249 { 250 int i; 251 252 for (i = 0; i < dst_len; i++) { 253 dst[i] = i < src_len ? src[i] : 0; 254 } 255 } 256 257 static void read_event_data(SCLPEventFacility *ef, SCCB *sccb) 258 { 259 sccb_mask_t sclp_active_selection_mask; 260 sccb_mask_t sclp_cp_receive_mask; 261 262 ReadEventData *red = (ReadEventData *) sccb; 263 264 if (be16_to_cpu(sccb->h.length) != SCCB_SIZE) { 265 sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); 266 goto out; 267 } 268 269 sclp_cp_receive_mask = ef->receive_mask; 270 271 /* get active selection mask */ 272 switch (sccb->h.function_code) { 273 case SCLP_UNCONDITIONAL_READ: 274 sclp_active_selection_mask = sclp_cp_receive_mask; 275 break; 276 case SCLP_SELECTIVE_READ: 277 copy_mask((uint8_t *)&sclp_active_selection_mask, (uint8_t *)&red->mask, 278 sizeof(sclp_active_selection_mask), ef->mask_length); 279 sclp_active_selection_mask = be64_to_cpu(sclp_active_selection_mask); 280 if (!sclp_cp_receive_mask || 281 (sclp_active_selection_mask & ~sclp_cp_receive_mask)) { 282 sccb->h.response_code = 283 cpu_to_be16(SCLP_RC_INVALID_SELECTION_MASK); 284 goto out; 285 } 286 break; 287 default: 288 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION); 289 goto out; 290 } 291 sccb->h.response_code = cpu_to_be16( 292 handle_sccb_read_events(ef, sccb, sclp_active_selection_mask)); 293 294 out: 295 return; 296 } 297 298 static void write_event_mask(SCLPEventFacility *ef, SCCB *sccb) 299 { 300 WriteEventMask *we_mask = (WriteEventMask *) sccb; 301 uint16_t mask_length = be16_to_cpu(we_mask->mask_length); 302 sccb_mask_t tmp_mask; 303 304 if (!mask_length || (mask_length > SCLP_EVENT_MASK_LEN_MAX) || 305 ((mask_length != 4) && !ef->allow_all_mask_sizes)) { 306 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_MASK_LENGTH); 307 goto out; 308 } 309 310 /* 311 * Note: We currently only support masks up to 8 byte length; 312 * the remainder is filled up with zeroes. Older Linux 313 * kernels use a 4 byte mask length, newer ones can use both 314 * 8 or 4 depending on what is available on the host. 315 */ 316 317 /* keep track of the guest's capability masks */ 318 copy_mask((uint8_t *)&tmp_mask, WEM_CP_RECEIVE_MASK(we_mask, mask_length), 319 sizeof(tmp_mask), mask_length); 320 ef->receive_mask = be64_to_cpu(tmp_mask); 321 322 /* return the SCLP's capability masks to the guest */ 323 tmp_mask = cpu_to_be64(get_host_receive_mask(ef)); 324 copy_mask(WEM_RECEIVE_MASK(we_mask, mask_length), (uint8_t *)&tmp_mask, 325 mask_length, sizeof(tmp_mask)); 326 tmp_mask = cpu_to_be64(get_host_send_mask(ef)); 327 copy_mask(WEM_SEND_MASK(we_mask, mask_length), (uint8_t *)&tmp_mask, 328 mask_length, sizeof(tmp_mask)); 329 330 sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_COMPLETION); 331 ef->mask_length = mask_length; 332 333 out: 334 return; 335 } 336 337 /* qemu object creation and initialization functions */ 338 339 #define TYPE_SCLP_EVENTS_BUS "s390-sclp-events-bus" 340 341 static void sclp_events_bus_realize(BusState *bus, Error **errp) 342 { 343 BusChild *kid; 344 345 /* TODO: recursive realization has to be done in common code */ 346 QTAILQ_FOREACH(kid, &bus->children, sibling) { 347 DeviceState *dev = kid->child; 348 349 object_property_set_bool(OBJECT(dev), true, "realized", errp); 350 if (*errp) { 351 return; 352 } 353 } 354 } 355 356 static void sclp_events_bus_class_init(ObjectClass *klass, void *data) 357 { 358 BusClass *bc = BUS_CLASS(klass); 359 360 bc->realize = sclp_events_bus_realize; 361 } 362 363 static const TypeInfo sclp_events_bus_info = { 364 .name = TYPE_SCLP_EVENTS_BUS, 365 .parent = TYPE_BUS, 366 .class_init = sclp_events_bus_class_init, 367 }; 368 369 static void command_handler(SCLPEventFacility *ef, SCCB *sccb, uint64_t code) 370 { 371 switch (code & SCLP_CMD_CODE_MASK) { 372 case SCLP_CMD_READ_EVENT_DATA: 373 read_event_data(ef, sccb); 374 break; 375 case SCLP_CMD_WRITE_EVENT_DATA: 376 write_event_data(ef, sccb); 377 break; 378 case SCLP_CMD_WRITE_EVENT_MASK: 379 write_event_mask(ef, sccb); 380 break; 381 default: 382 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND); 383 break; 384 } 385 } 386 387 static bool vmstate_event_facility_mask64_needed(void *opaque) 388 { 389 SCLPEventFacility *ef = opaque; 390 391 return (ef->receive_mask & 0xFFFFFFFF) != 0; 392 } 393 394 static bool vmstate_event_facility_mask_length_needed(void *opaque) 395 { 396 SCLPEventFacility *ef = opaque; 397 398 return ef->allow_all_mask_sizes; 399 } 400 401 static const VMStateDescription vmstate_event_facility_mask64 = { 402 .name = "vmstate-event-facility/mask64", 403 .version_id = 0, 404 .minimum_version_id = 0, 405 .needed = vmstate_event_facility_mask64_needed, 406 .fields = (VMStateField[]) { 407 VMSTATE_UINT32(receive_mask_pieces[RECV_MASK_LOWER], SCLPEventFacility), 408 VMSTATE_END_OF_LIST() 409 } 410 }; 411 412 static const VMStateDescription vmstate_event_facility_mask_length = { 413 .name = "vmstate-event-facility/mask_length", 414 .version_id = 0, 415 .minimum_version_id = 0, 416 .needed = vmstate_event_facility_mask_length_needed, 417 .fields = (VMStateField[]) { 418 VMSTATE_UINT16(mask_length, SCLPEventFacility), 419 VMSTATE_END_OF_LIST() 420 } 421 }; 422 423 static const VMStateDescription vmstate_event_facility = { 424 .name = "vmstate-event-facility", 425 .version_id = 0, 426 .minimum_version_id = 0, 427 .fields = (VMStateField[]) { 428 VMSTATE_UINT32(receive_mask_pieces[RECV_MASK_UPPER], SCLPEventFacility), 429 VMSTATE_END_OF_LIST() 430 }, 431 .subsections = (const VMStateDescription * []) { 432 &vmstate_event_facility_mask64, 433 &vmstate_event_facility_mask_length, 434 NULL 435 } 436 }; 437 438 static void sclp_event_set_allow_all_mask_sizes(Object *obj, bool value, 439 Error **errp) 440 { 441 SCLPEventFacility *ef = (SCLPEventFacility *)obj; 442 443 ef->allow_all_mask_sizes = value; 444 } 445 446 static bool sclp_event_get_allow_all_mask_sizes(Object *obj, Error **e) 447 { 448 SCLPEventFacility *ef = (SCLPEventFacility *)obj; 449 450 return ef->allow_all_mask_sizes; 451 } 452 453 static void init_event_facility(Object *obj) 454 { 455 SCLPEventFacility *event_facility = EVENT_FACILITY(obj); 456 DeviceState *sdev = DEVICE(obj); 457 Object *new; 458 459 event_facility->mask_length = 4; 460 event_facility->allow_all_mask_sizes = true; 461 object_property_add_bool(obj, "allow_all_mask_sizes", 462 sclp_event_get_allow_all_mask_sizes, 463 sclp_event_set_allow_all_mask_sizes, NULL); 464 /* Spawn a new bus for SCLP events */ 465 qbus_create_inplace(&event_facility->sbus, sizeof(event_facility->sbus), 466 TYPE_SCLP_EVENTS_BUS, sdev, NULL); 467 468 new = object_new(TYPE_SCLP_QUIESCE); 469 object_property_add_child(obj, TYPE_SCLP_QUIESCE, new, NULL); 470 object_unref(new); 471 qdev_set_parent_bus(DEVICE(new), BUS(&event_facility->sbus)); 472 473 new = object_new(TYPE_SCLP_CPU_HOTPLUG); 474 object_property_add_child(obj, TYPE_SCLP_CPU_HOTPLUG, new, NULL); 475 object_unref(new); 476 qdev_set_parent_bus(DEVICE(new), BUS(&event_facility->sbus)); 477 /* the facility will automatically realize the devices via the bus */ 478 } 479 480 static void reset_event_facility(DeviceState *dev) 481 { 482 SCLPEventFacility *sdev = EVENT_FACILITY(dev); 483 484 sdev->receive_mask = 0; 485 } 486 487 static void init_event_facility_class(ObjectClass *klass, void *data) 488 { 489 SysBusDeviceClass *sbdc = SYS_BUS_DEVICE_CLASS(klass); 490 DeviceClass *dc = DEVICE_CLASS(sbdc); 491 SCLPEventFacilityClass *k = EVENT_FACILITY_CLASS(dc); 492 493 dc->reset = reset_event_facility; 494 dc->vmsd = &vmstate_event_facility; 495 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 496 k->command_handler = command_handler; 497 k->event_pending = event_pending; 498 } 499 500 static const TypeInfo sclp_event_facility_info = { 501 .name = TYPE_SCLP_EVENT_FACILITY, 502 .parent = TYPE_SYS_BUS_DEVICE, 503 .instance_init = init_event_facility, 504 .instance_size = sizeof(SCLPEventFacility), 505 .class_init = init_event_facility_class, 506 .class_size = sizeof(SCLPEventFacilityClass), 507 }; 508 509 static void event_realize(DeviceState *qdev, Error **errp) 510 { 511 SCLPEvent *event = SCLP_EVENT(qdev); 512 SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event); 513 514 if (child->init) { 515 int rc = child->init(event); 516 if (rc < 0) { 517 error_setg(errp, "SCLP event initialization failed."); 518 return; 519 } 520 } 521 } 522 523 static void event_class_init(ObjectClass *klass, void *data) 524 { 525 DeviceClass *dc = DEVICE_CLASS(klass); 526 527 dc->bus_type = TYPE_SCLP_EVENTS_BUS; 528 dc->realize = event_realize; 529 } 530 531 static const TypeInfo sclp_event_type_info = { 532 .name = TYPE_SCLP_EVENT, 533 .parent = TYPE_DEVICE, 534 .instance_size = sizeof(SCLPEvent), 535 .class_init = event_class_init, 536 .class_size = sizeof(SCLPEventClass), 537 .abstract = true, 538 }; 539 540 static void register_types(void) 541 { 542 type_register_static(&sclp_events_bus_info); 543 type_register_static(&sclp_event_facility_info); 544 type_register_static(&sclp_event_type_info); 545 } 546 547 type_init(register_types) 548 549 BusState *sclp_get_event_facility_bus(void) 550 { 551 Object *busobj; 552 SCLPEventsBus *sbus; 553 554 busobj = object_resolve_path_type("", TYPE_SCLP_EVENTS_BUS, NULL); 555 sbus = OBJECT_CHECK(SCLPEventsBus, busobj, TYPE_SCLP_EVENTS_BUS); 556 if (!sbus) { 557 return NULL; 558 } 559 560 return &sbus->qbus; 561 } 562