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