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 * - Control-Program Identification - Send OS data from guest to host 8 * 9 * Copyright IBM, Corp. 2012 10 * 11 * Authors: 12 * Heinz Graalfs <graalfs@de.ibm.com> 13 * 14 * This work is licensed under the terms of the GNU GPL, version 2 or (at your 15 * option) any later version. See the COPYING file in the top-level directory. 16 * 17 */ 18 19 #include "qemu/osdep.h" 20 #include "qapi/error.h" 21 #include "qemu/module.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 #if HOST_BIG_ENDIAN 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 SCLPEvent quiesce, cpu_hotplug; 44 SCLPEventCPI cpi; 45 /* guest's receive mask */ 46 union { 47 uint32_t receive_mask_pieces[2]; 48 sccb_mask_t receive_mask; 49 }; 50 /* length of the receive mask */ 51 uint16_t mask_length; 52 }; 53 54 /* return true if any child has event pending set */ 55 static bool event_pending(SCLPEventFacility *ef) 56 { 57 BusChild *kid; 58 SCLPEvent *event; 59 SCLPEventClass *event_class; 60 61 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 62 event = SCLP_EVENT(kid->child); 63 event_class = SCLP_EVENT_GET_CLASS(event); 64 if (event->event_pending && 65 event_class->get_send_mask() & ef->receive_mask) { 66 return true; 67 } 68 } 69 return false; 70 } 71 72 static sccb_mask_t get_host_send_mask(SCLPEventFacility *ef) 73 { 74 sccb_mask_t mask; 75 BusChild *kid; 76 SCLPEventClass *child; 77 78 mask = 0; 79 80 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 81 DeviceState *qdev = kid->child; 82 child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev); 83 mask |= child->get_send_mask(); 84 } 85 return mask; 86 } 87 88 static sccb_mask_t get_host_receive_mask(SCLPEventFacility *ef) 89 { 90 sccb_mask_t mask; 91 BusChild *kid; 92 SCLPEventClass *child; 93 94 mask = 0; 95 96 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 97 DeviceState *qdev = kid->child; 98 child = SCLP_EVENT_GET_CLASS((SCLPEvent *) qdev); 99 mask |= child->get_receive_mask(); 100 } 101 return mask; 102 } 103 104 static uint16_t write_event_length_check(SCCB *sccb) 105 { 106 int slen; 107 unsigned elen = 0; 108 EventBufferHeader *event; 109 WriteEventData *wed = (WriteEventData *) sccb; 110 111 event = (EventBufferHeader *) &wed->ebh; 112 for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) { 113 elen = be16_to_cpu(event->length); 114 if (elen < sizeof(*event) || elen > slen) { 115 return SCLP_RC_EVENT_BUFFER_SYNTAX_ERROR; 116 } 117 event = (void *) event + elen; 118 } 119 if (slen) { 120 return SCLP_RC_INCONSISTENT_LENGTHS; 121 } 122 return SCLP_RC_NORMAL_COMPLETION; 123 } 124 125 static uint16_t handle_write_event_buf(SCLPEventFacility *ef, 126 EventBufferHeader *event_buf, SCCB *sccb) 127 { 128 uint16_t rc; 129 BusChild *kid; 130 SCLPEvent *event; 131 SCLPEventClass *ec; 132 133 rc = SCLP_RC_INVALID_FUNCTION; 134 135 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 136 DeviceState *qdev = kid->child; 137 event = (SCLPEvent *) qdev; 138 ec = SCLP_EVENT_GET_CLASS(event); 139 140 if (ec->write_event_data && 141 ec->can_handle_event(event_buf->type)) { 142 rc = ec->write_event_data(event, event_buf); 143 break; 144 } 145 } 146 return rc; 147 } 148 149 static uint16_t handle_sccb_write_events(SCLPEventFacility *ef, SCCB *sccb) 150 { 151 uint16_t rc; 152 int slen; 153 unsigned elen = 0; 154 EventBufferHeader *event_buf; 155 WriteEventData *wed = (WriteEventData *) sccb; 156 157 event_buf = &wed->ebh; 158 rc = SCLP_RC_NORMAL_COMPLETION; 159 160 /* loop over all contained event buffers */ 161 for (slen = sccb_data_len(sccb); slen > 0; slen -= elen) { 162 elen = be16_to_cpu(event_buf->length); 163 164 /* in case of a previous error mark all trailing buffers 165 * as not accepted */ 166 if (rc != SCLP_RC_NORMAL_COMPLETION) { 167 event_buf->flags &= ~(SCLP_EVENT_BUFFER_ACCEPTED); 168 } else { 169 rc = handle_write_event_buf(ef, event_buf, sccb); 170 } 171 event_buf = (void *) event_buf + elen; 172 } 173 return rc; 174 } 175 176 static void write_event_data(SCLPEventFacility *ef, SCCB *sccb) 177 { 178 if (sccb->h.function_code != SCLP_FC_NORMAL_WRITE) { 179 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION); 180 return; 181 } 182 if (be16_to_cpu(sccb->h.length) < 8) { 183 sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); 184 return; 185 } 186 /* first do a sanity check of the write events */ 187 sccb->h.response_code = cpu_to_be16(write_event_length_check(sccb)); 188 189 /* if no early error, then execute */ 190 if (sccb->h.response_code == be16_to_cpu(SCLP_RC_NORMAL_COMPLETION)) { 191 sccb->h.response_code = 192 cpu_to_be16(handle_sccb_write_events(ef, sccb)); 193 } 194 } 195 196 static uint16_t handle_sccb_read_events(SCLPEventFacility *ef, SCCB *sccb, 197 sccb_mask_t mask) 198 { 199 uint16_t rc; 200 int slen; 201 unsigned elen; 202 BusChild *kid; 203 SCLPEvent *event; 204 SCLPEventClass *ec; 205 EventBufferHeader *event_buf; 206 ReadEventData *red = (ReadEventData *) sccb; 207 208 event_buf = &red->ebh; 209 event_buf->length = 0; 210 slen = sccb_data_len(sccb); 211 212 rc = SCLP_RC_NO_EVENT_BUFFERS_STORED; 213 214 QTAILQ_FOREACH(kid, &ef->sbus.qbus.children, sibling) { 215 DeviceState *qdev = kid->child; 216 event = (SCLPEvent *) qdev; 217 ec = SCLP_EVENT_GET_CLASS(event); 218 219 if (mask & ec->get_send_mask()) { 220 if (ec->read_event_data(event, event_buf, &slen)) { 221 elen = be16_to_cpu(event_buf->length); 222 event_buf = (EventBufferHeader *) ((char *)event_buf + elen); 223 rc = SCLP_RC_NORMAL_COMPLETION; 224 } 225 } 226 } 227 228 if (sccb->h.control_mask[2] & SCLP_VARIABLE_LENGTH_RESPONSE) { 229 /* architecture suggests to reset variable-length-response bit */ 230 sccb->h.control_mask[2] &= ~SCLP_VARIABLE_LENGTH_RESPONSE; 231 /* with a new length value */ 232 sccb->h.length = cpu_to_be16(SCCB_SIZE - slen); 233 } 234 return rc; 235 } 236 237 /* copy up to src_len bytes and fill the rest of dst with zeroes */ 238 static void copy_mask(uint8_t *dst, uint8_t *src, uint16_t dst_len, 239 uint16_t src_len) 240 { 241 int i; 242 243 for (i = 0; i < dst_len; i++) { 244 dst[i] = i < src_len ? src[i] : 0; 245 } 246 } 247 248 static void read_event_data(SCLPEventFacility *ef, SCCB *sccb) 249 { 250 sccb_mask_t sclp_active_selection_mask; 251 sccb_mask_t sclp_cp_receive_mask; 252 253 ReadEventData *red = (ReadEventData *) sccb; 254 255 if (be16_to_cpu(sccb->h.length) != SCCB_SIZE) { 256 sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); 257 return; 258 } 259 260 switch (sccb->h.function_code) { 261 case SCLP_UNCONDITIONAL_READ: 262 sccb->h.response_code = cpu_to_be16( 263 handle_sccb_read_events(ef, sccb, ef->receive_mask)); 264 break; 265 case SCLP_SELECTIVE_READ: 266 /* get active selection mask */ 267 sclp_cp_receive_mask = ef->receive_mask; 268 269 copy_mask((uint8_t *)&sclp_active_selection_mask, (uint8_t *)&red->mask, 270 sizeof(sclp_active_selection_mask), ef->mask_length); 271 sclp_active_selection_mask = be64_to_cpu(sclp_active_selection_mask); 272 if (!sclp_cp_receive_mask || 273 (sclp_active_selection_mask & ~sclp_cp_receive_mask)) { 274 sccb->h.response_code = 275 cpu_to_be16(SCLP_RC_INVALID_SELECTION_MASK); 276 } else { 277 sccb->h.response_code = cpu_to_be16( 278 handle_sccb_read_events(ef, sccb, sclp_active_selection_mask)); 279 } 280 break; 281 default: 282 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_FUNCTION); 283 } 284 } 285 286 static void write_event_mask(SCLPEventFacility *ef, SCCB *sccb) 287 { 288 WriteEventMask *we_mask = (WriteEventMask *) sccb; 289 uint16_t mask_length = be16_to_cpu(we_mask->mask_length); 290 sccb_mask_t tmp_mask; 291 292 if (!mask_length || mask_length > SCLP_EVENT_MASK_LEN_MAX) { 293 sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_MASK_LENGTH); 294 return; 295 } 296 297 /* 298 * Note: We currently only support masks up to 8 byte length; 299 * the remainder is filled up with zeroes. Older Linux 300 * kernels use a 4 byte mask length, newer ones can use both 301 * 8 or 4 depending on what is available on the host. 302 */ 303 304 /* keep track of the guest's capability masks */ 305 copy_mask((uint8_t *)&tmp_mask, WEM_CP_RECEIVE_MASK(we_mask, mask_length), 306 sizeof(tmp_mask), mask_length); 307 ef->receive_mask = be64_to_cpu(tmp_mask); 308 309 /* return the SCLP's capability masks to the guest */ 310 tmp_mask = cpu_to_be64(get_host_receive_mask(ef)); 311 copy_mask(WEM_RECEIVE_MASK(we_mask, mask_length), (uint8_t *)&tmp_mask, 312 mask_length, sizeof(tmp_mask)); 313 tmp_mask = cpu_to_be64(get_host_send_mask(ef)); 314 copy_mask(WEM_SEND_MASK(we_mask, mask_length), (uint8_t *)&tmp_mask, 315 mask_length, sizeof(tmp_mask)); 316 317 sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_COMPLETION); 318 ef->mask_length = mask_length; 319 } 320 321 /* qemu object creation and initialization functions */ 322 323 #define TYPE_SCLP_EVENTS_BUS "s390-sclp-events-bus" 324 325 static const TypeInfo sclp_events_bus_info = { 326 .name = TYPE_SCLP_EVENTS_BUS, 327 .parent = TYPE_BUS, 328 }; 329 330 static void command_handler(SCLPEventFacility *ef, SCCB *sccb, uint64_t code) 331 { 332 switch (code & SCLP_CMD_CODE_MASK) { 333 case SCLP_CMD_READ_EVENT_DATA: 334 read_event_data(ef, sccb); 335 break; 336 case SCLP_CMD_WRITE_EVENT_DATA: 337 write_event_data(ef, sccb); 338 break; 339 case SCLP_CMD_WRITE_EVENT_MASK: 340 write_event_mask(ef, sccb); 341 break; 342 } 343 } 344 345 static bool vmstate_event_facility_mask64_needed(void *opaque) 346 { 347 SCLPEventFacility *ef = opaque; 348 349 return (ef->receive_mask & 0xFFFFFFFF) != 0; 350 } 351 352 static const VMStateDescription vmstate_event_facility_mask64 = { 353 .name = "vmstate-event-facility/mask64", 354 .version_id = 0, 355 .minimum_version_id = 0, 356 .needed = vmstate_event_facility_mask64_needed, 357 .fields = (const VMStateField[]) { 358 VMSTATE_UINT32(receive_mask_pieces[RECV_MASK_LOWER], SCLPEventFacility), 359 VMSTATE_END_OF_LIST() 360 } 361 }; 362 363 static const VMStateDescription vmstate_event_facility_mask_length = { 364 .name = "vmstate-event-facility/mask_length", 365 .version_id = 0, 366 .minimum_version_id = 0, 367 .fields = (const VMStateField[]) { 368 VMSTATE_UINT16(mask_length, SCLPEventFacility), 369 VMSTATE_END_OF_LIST() 370 } 371 }; 372 373 static const VMStateDescription vmstate_event_facility = { 374 .name = "vmstate-event-facility", 375 .version_id = 0, 376 .minimum_version_id = 0, 377 .fields = (const VMStateField[]) { 378 VMSTATE_UINT32(receive_mask_pieces[RECV_MASK_UPPER], SCLPEventFacility), 379 VMSTATE_END_OF_LIST() 380 }, 381 .subsections = (const VMStateDescription * const []) { 382 &vmstate_event_facility_mask64, 383 &vmstate_event_facility_mask_length, 384 NULL 385 } 386 }; 387 388 static void init_event_facility(Object *obj) 389 { 390 SCLPEventFacility *event_facility = EVENT_FACILITY(obj); 391 DeviceState *sdev = DEVICE(obj); 392 393 event_facility->mask_length = 4; 394 395 /* Spawn a new bus for SCLP events */ 396 qbus_init(&event_facility->sbus, sizeof(event_facility->sbus), 397 TYPE_SCLP_EVENTS_BUS, sdev, NULL); 398 399 object_initialize_child(obj, TYPE_SCLP_QUIESCE, 400 &event_facility->quiesce, 401 TYPE_SCLP_QUIESCE); 402 403 object_initialize_child(obj, TYPE_SCLP_CPU_HOTPLUG, 404 &event_facility->cpu_hotplug, 405 TYPE_SCLP_CPU_HOTPLUG); 406 } 407 408 static void realize_event_facility(DeviceState *dev, Error **errp) 409 { 410 SCLPEventFacility *event_facility = EVENT_FACILITY(dev); 411 412 if (!qdev_realize(DEVICE(&event_facility->quiesce), 413 BUS(&event_facility->sbus), errp)) { 414 return; 415 } 416 if (!qdev_realize(DEVICE(&event_facility->cpu_hotplug), 417 BUS(&event_facility->sbus), errp)) { 418 qdev_unrealize(DEVICE(&event_facility->quiesce)); 419 return; 420 } 421 } 422 423 static void reset_event_facility(DeviceState *dev) 424 { 425 SCLPEventFacility *sdev = EVENT_FACILITY(dev); 426 427 sdev->receive_mask = 0; 428 } 429 430 static void init_event_facility_class(ObjectClass *klass, const void *data) 431 { 432 SysBusDeviceClass *sbdc = SYS_BUS_DEVICE_CLASS(klass); 433 DeviceClass *dc = DEVICE_CLASS(sbdc); 434 SCLPEventFacilityClass *k = EVENT_FACILITY_CLASS(dc); 435 436 dc->realize = realize_event_facility; 437 device_class_set_legacy_reset(dc, reset_event_facility); 438 dc->vmsd = &vmstate_event_facility; 439 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 440 k->command_handler = command_handler; 441 k->event_pending = event_pending; 442 } 443 444 static const TypeInfo sclp_event_facility_info = { 445 .name = TYPE_SCLP_EVENT_FACILITY, 446 .parent = TYPE_SYS_BUS_DEVICE, 447 .instance_init = init_event_facility, 448 .instance_size = sizeof(SCLPEventFacility), 449 .class_init = init_event_facility_class, 450 .class_size = sizeof(SCLPEventFacilityClass), 451 }; 452 453 static void event_realize(DeviceState *qdev, Error **errp) 454 { 455 SCLPEvent *event = SCLP_EVENT(qdev); 456 SCLPEventClass *child = SCLP_EVENT_GET_CLASS(event); 457 458 if (child->init) { 459 int rc = child->init(event); 460 if (rc < 0) { 461 error_setg(errp, "SCLP event initialization failed."); 462 return; 463 } 464 } 465 } 466 467 static void event_class_init(ObjectClass *klass, const void *data) 468 { 469 DeviceClass *dc = DEVICE_CLASS(klass); 470 471 dc->bus_type = TYPE_SCLP_EVENTS_BUS; 472 dc->realize = event_realize; 473 } 474 475 static const TypeInfo sclp_event_type_info = { 476 .name = TYPE_SCLP_EVENT, 477 .parent = TYPE_DEVICE, 478 .instance_size = sizeof(SCLPEvent), 479 .class_init = event_class_init, 480 .class_size = sizeof(SCLPEventClass), 481 .abstract = true, 482 }; 483 484 static void register_types(void) 485 { 486 type_register_static(&sclp_events_bus_info); 487 type_register_static(&sclp_event_facility_info); 488 type_register_static(&sclp_event_type_info); 489 } 490 491 type_init(register_types) 492 493 BusState *sclp_get_event_facility_bus(SCLPEventFacility *ef) 494 { 495 return BUS(&ef->sbus); 496 } 497