1 /* 2 * A bus for connecting virtio serial and console ports 3 * 4 * Copyright (C) 2009, 2010 Red Hat, Inc. 5 * 6 * Author(s): 7 * Amit Shah <amit.shah@redhat.com> 8 * 9 * Some earlier parts are: 10 * Copyright IBM, Corp. 2008 11 * authored by 12 * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> 13 * 14 * This work is licensed under the terms of the GNU GPL, version 2. See 15 * the COPYING file in the top-level directory. 16 * 17 * Contributions after 2012-01-13 are licensed under the terms of the 18 * GNU GPL, version 2 or (at your option) any later version. 19 */ 20 21 #include "qemu/iov.h" 22 #include "monitor/monitor.h" 23 #include "qemu/error-report.h" 24 #include "qemu/queue.h" 25 #include "hw/sysbus.h" 26 #include "trace.h" 27 #include "hw/virtio/virtio-serial.h" 28 #include "hw/virtio/virtio-access.h" 29 30 static struct VirtIOSerialDevices { 31 QLIST_HEAD(, VirtIOSerial) devices; 32 } vserdevices; 33 34 static VirtIOSerialPort *find_port_by_id(VirtIOSerial *vser, uint32_t id) 35 { 36 VirtIOSerialPort *port; 37 38 if (id == VIRTIO_CONSOLE_BAD_ID) { 39 return NULL; 40 } 41 42 QTAILQ_FOREACH(port, &vser->ports, next) { 43 if (port->id == id) 44 return port; 45 } 46 return NULL; 47 } 48 49 static VirtIOSerialPort *find_port_by_vq(VirtIOSerial *vser, VirtQueue *vq) 50 { 51 VirtIOSerialPort *port; 52 53 QTAILQ_FOREACH(port, &vser->ports, next) { 54 if (port->ivq == vq || port->ovq == vq) 55 return port; 56 } 57 return NULL; 58 } 59 60 static VirtIOSerialPort *find_port_by_name(char *name) 61 { 62 VirtIOSerial *vser; 63 64 QLIST_FOREACH(vser, &vserdevices.devices, next) { 65 VirtIOSerialPort *port; 66 67 QTAILQ_FOREACH(port, &vser->ports, next) { 68 if (port->name && !strcmp(port->name, name)) { 69 return port; 70 } 71 } 72 } 73 return NULL; 74 } 75 76 static bool use_multiport(VirtIOSerial *vser) 77 { 78 VirtIODevice *vdev = VIRTIO_DEVICE(vser); 79 return virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT); 80 } 81 82 static size_t write_to_port(VirtIOSerialPort *port, 83 const uint8_t *buf, size_t size) 84 { 85 VirtQueueElement elem; 86 VirtQueue *vq; 87 size_t offset; 88 89 vq = port->ivq; 90 if (!virtio_queue_ready(vq)) { 91 return 0; 92 } 93 94 offset = 0; 95 while (offset < size) { 96 size_t len; 97 98 if (!virtqueue_pop(vq, &elem)) { 99 break; 100 } 101 102 len = iov_from_buf(elem.in_sg, elem.in_num, 0, 103 buf + offset, size - offset); 104 offset += len; 105 106 virtqueue_push(vq, &elem, len); 107 } 108 109 virtio_notify(VIRTIO_DEVICE(port->vser), vq); 110 return offset; 111 } 112 113 static void discard_vq_data(VirtQueue *vq, VirtIODevice *vdev) 114 { 115 VirtQueueElement elem; 116 117 if (!virtio_queue_ready(vq)) { 118 return; 119 } 120 while (virtqueue_pop(vq, &elem)) { 121 virtqueue_push(vq, &elem, 0); 122 } 123 virtio_notify(vdev, vq); 124 } 125 126 static void do_flush_queued_data(VirtIOSerialPort *port, VirtQueue *vq, 127 VirtIODevice *vdev) 128 { 129 VirtIOSerialPortClass *vsc; 130 131 assert(port); 132 assert(virtio_queue_ready(vq)); 133 134 vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); 135 136 while (!port->throttled) { 137 unsigned int i; 138 139 /* Pop an elem only if we haven't left off a previous one mid-way */ 140 if (!port->elem.out_num) { 141 if (!virtqueue_pop(vq, &port->elem)) { 142 break; 143 } 144 port->iov_idx = 0; 145 port->iov_offset = 0; 146 } 147 148 for (i = port->iov_idx; i < port->elem.out_num; i++) { 149 size_t buf_size; 150 ssize_t ret; 151 152 buf_size = port->elem.out_sg[i].iov_len - port->iov_offset; 153 ret = vsc->have_data(port, 154 port->elem.out_sg[i].iov_base 155 + port->iov_offset, 156 buf_size); 157 if (port->throttled) { 158 port->iov_idx = i; 159 if (ret > 0) { 160 port->iov_offset += ret; 161 } 162 break; 163 } 164 port->iov_offset = 0; 165 } 166 if (port->throttled) { 167 break; 168 } 169 virtqueue_push(vq, &port->elem, 0); 170 port->elem.out_num = 0; 171 } 172 virtio_notify(vdev, vq); 173 } 174 175 static void flush_queued_data(VirtIOSerialPort *port) 176 { 177 assert(port); 178 179 if (!virtio_queue_ready(port->ovq)) { 180 return; 181 } 182 do_flush_queued_data(port, port->ovq, VIRTIO_DEVICE(port->vser)); 183 } 184 185 static size_t send_control_msg(VirtIOSerial *vser, void *buf, size_t len) 186 { 187 VirtQueueElement elem; 188 VirtQueue *vq; 189 190 vq = vser->c_ivq; 191 if (!virtio_queue_ready(vq)) { 192 return 0; 193 } 194 if (!virtqueue_pop(vq, &elem)) { 195 return 0; 196 } 197 198 memcpy(elem.in_sg[0].iov_base, buf, len); 199 200 virtqueue_push(vq, &elem, len); 201 virtio_notify(VIRTIO_DEVICE(vser), vq); 202 return len; 203 } 204 205 static size_t send_control_event(VirtIOSerial *vser, uint32_t port_id, 206 uint16_t event, uint16_t value) 207 { 208 VirtIODevice *vdev = VIRTIO_DEVICE(vser); 209 struct virtio_console_control cpkt; 210 211 virtio_stl_p(vdev, &cpkt.id, port_id); 212 virtio_stw_p(vdev, &cpkt.event, event); 213 virtio_stw_p(vdev, &cpkt.value, value); 214 215 trace_virtio_serial_send_control_event(port_id, event, value); 216 return send_control_msg(vser, &cpkt, sizeof(cpkt)); 217 } 218 219 /* Functions for use inside qemu to open and read from/write to ports */ 220 int virtio_serial_open(VirtIOSerialPort *port) 221 { 222 /* Don't allow opening an already-open port */ 223 if (port->host_connected) { 224 return 0; 225 } 226 /* Send port open notification to the guest */ 227 port->host_connected = true; 228 send_control_event(port->vser, port->id, VIRTIO_CONSOLE_PORT_OPEN, 1); 229 230 return 0; 231 } 232 233 int virtio_serial_close(VirtIOSerialPort *port) 234 { 235 port->host_connected = false; 236 /* 237 * If there's any data the guest sent which the app didn't 238 * consume, reset the throttling flag and discard the data. 239 */ 240 port->throttled = false; 241 discard_vq_data(port->ovq, VIRTIO_DEVICE(port->vser)); 242 243 send_control_event(port->vser, port->id, VIRTIO_CONSOLE_PORT_OPEN, 0); 244 245 return 0; 246 } 247 248 /* Individual ports/apps call this function to write to the guest. */ 249 ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf, 250 size_t size) 251 { 252 if (!port || !port->host_connected || !port->guest_connected) { 253 return 0; 254 } 255 return write_to_port(port, buf, size); 256 } 257 258 /* 259 * Readiness of the guest to accept data on a port. 260 * Returns max. data the guest can receive 261 */ 262 size_t virtio_serial_guest_ready(VirtIOSerialPort *port) 263 { 264 VirtIODevice *vdev = VIRTIO_DEVICE(port->vser); 265 VirtQueue *vq = port->ivq; 266 unsigned int bytes; 267 268 if (!virtio_queue_ready(vq) || 269 !(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) || 270 virtio_queue_empty(vq)) { 271 return 0; 272 } 273 if (use_multiport(port->vser) && !port->guest_connected) { 274 return 0; 275 } 276 virtqueue_get_avail_bytes(vq, &bytes, NULL, 4096, 0); 277 return bytes; 278 } 279 280 static void flush_queued_data_bh(void *opaque) 281 { 282 VirtIOSerialPort *port = opaque; 283 284 flush_queued_data(port); 285 } 286 287 void virtio_serial_throttle_port(VirtIOSerialPort *port, bool throttle) 288 { 289 if (!port) { 290 return; 291 } 292 293 trace_virtio_serial_throttle_port(port->id, throttle); 294 port->throttled = throttle; 295 if (throttle) { 296 return; 297 } 298 qemu_bh_schedule(port->bh); 299 } 300 301 /* Guest wants to notify us of some event */ 302 static void handle_control_message(VirtIOSerial *vser, void *buf, size_t len) 303 { 304 VirtIODevice *vdev = VIRTIO_DEVICE(vser); 305 struct VirtIOSerialPort *port; 306 VirtIOSerialPortClass *vsc; 307 struct virtio_console_control cpkt, *gcpkt; 308 uint8_t *buffer; 309 size_t buffer_len; 310 311 gcpkt = buf; 312 313 if (len < sizeof(cpkt)) { 314 /* The guest sent an invalid control packet */ 315 return; 316 } 317 318 cpkt.event = virtio_lduw_p(vdev, &gcpkt->event); 319 cpkt.value = virtio_lduw_p(vdev, &gcpkt->value); 320 321 trace_virtio_serial_handle_control_message(cpkt.event, cpkt.value); 322 323 if (cpkt.event == VIRTIO_CONSOLE_DEVICE_READY) { 324 if (!cpkt.value) { 325 error_report("virtio-serial-bus: Guest failure in adding device %s", 326 vser->bus.qbus.name); 327 return; 328 } 329 /* 330 * The device is up, we can now tell the device about all the 331 * ports we have here. 332 */ 333 QTAILQ_FOREACH(port, &vser->ports, next) { 334 send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_ADD, 1); 335 } 336 return; 337 } 338 339 port = find_port_by_id(vser, virtio_ldl_p(vdev, &gcpkt->id)); 340 if (!port) { 341 error_report("virtio-serial-bus: Unexpected port id %u for device %s", 342 virtio_ldl_p(vdev, &gcpkt->id), vser->bus.qbus.name); 343 return; 344 } 345 346 trace_virtio_serial_handle_control_message_port(port->id); 347 348 vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); 349 350 switch(cpkt.event) { 351 case VIRTIO_CONSOLE_PORT_READY: 352 if (!cpkt.value) { 353 error_report("virtio-serial-bus: Guest failure in adding port %u for device %s", 354 port->id, vser->bus.qbus.name); 355 break; 356 } 357 /* 358 * Now that we know the guest asked for the port name, we're 359 * sure the guest has initialised whatever state is necessary 360 * for this port. Now's a good time to let the guest know if 361 * this port is a console port so that the guest can hook it 362 * up to hvc. 363 */ 364 if (vsc->is_console) { 365 send_control_event(vser, port->id, VIRTIO_CONSOLE_CONSOLE_PORT, 1); 366 } 367 368 if (port->name) { 369 virtio_stl_p(vdev, &cpkt.id, port->id); 370 virtio_stw_p(vdev, &cpkt.event, VIRTIO_CONSOLE_PORT_NAME); 371 virtio_stw_p(vdev, &cpkt.value, 1); 372 373 buffer_len = sizeof(cpkt) + strlen(port->name) + 1; 374 buffer = g_malloc(buffer_len); 375 376 memcpy(buffer, &cpkt, sizeof(cpkt)); 377 memcpy(buffer + sizeof(cpkt), port->name, strlen(port->name)); 378 buffer[buffer_len - 1] = 0; 379 380 send_control_msg(vser, buffer, buffer_len); 381 g_free(buffer); 382 } 383 384 if (port->host_connected) { 385 send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_OPEN, 1); 386 } 387 388 /* 389 * When the guest has asked us for this information it means 390 * the guest is all setup and has its virtqueues 391 * initialised. If some app is interested in knowing about 392 * this event, let it know. 393 */ 394 if (vsc->guest_ready) { 395 vsc->guest_ready(port); 396 } 397 break; 398 399 case VIRTIO_CONSOLE_PORT_OPEN: 400 port->guest_connected = cpkt.value; 401 if (vsc->set_guest_connected) { 402 /* Send the guest opened notification if an app is interested */ 403 vsc->set_guest_connected(port, cpkt.value); 404 } 405 break; 406 } 407 } 408 409 static void control_in(VirtIODevice *vdev, VirtQueue *vq) 410 { 411 } 412 413 static void control_out(VirtIODevice *vdev, VirtQueue *vq) 414 { 415 VirtQueueElement elem; 416 VirtIOSerial *vser; 417 uint8_t *buf; 418 size_t len; 419 420 vser = VIRTIO_SERIAL(vdev); 421 422 len = 0; 423 buf = NULL; 424 while (virtqueue_pop(vq, &elem)) { 425 size_t cur_len; 426 427 cur_len = iov_size(elem.out_sg, elem.out_num); 428 /* 429 * Allocate a new buf only if we didn't have one previously or 430 * if the size of the buf differs 431 */ 432 if (cur_len > len) { 433 g_free(buf); 434 435 buf = g_malloc(cur_len); 436 len = cur_len; 437 } 438 iov_to_buf(elem.out_sg, elem.out_num, 0, buf, cur_len); 439 440 handle_control_message(vser, buf, cur_len); 441 virtqueue_push(vq, &elem, 0); 442 } 443 g_free(buf); 444 virtio_notify(vdev, vq); 445 } 446 447 /* Guest wrote something to some port. */ 448 static void handle_output(VirtIODevice *vdev, VirtQueue *vq) 449 { 450 VirtIOSerial *vser; 451 VirtIOSerialPort *port; 452 453 vser = VIRTIO_SERIAL(vdev); 454 port = find_port_by_vq(vser, vq); 455 456 if (!port || !port->host_connected) { 457 discard_vq_data(vq, vdev); 458 return; 459 } 460 461 if (!port->throttled) { 462 do_flush_queued_data(port, vq, vdev); 463 return; 464 } 465 } 466 467 static void handle_input(VirtIODevice *vdev, VirtQueue *vq) 468 { 469 /* 470 * Users of virtio-serial would like to know when guest becomes 471 * writable again -- i.e. if a vq had stuff queued up and the 472 * guest wasn't reading at all, the host would not be able to 473 * write to the vq anymore. Once the guest reads off something, 474 * we can start queueing things up again. However, this call is 475 * made for each buffer addition by the guest -- even though free 476 * buffers existed prior to the current buffer addition. This is 477 * done so as not to maintain previous state, which will need 478 * additional live-migration-related changes. 479 */ 480 VirtIOSerial *vser; 481 VirtIOSerialPort *port; 482 VirtIOSerialPortClass *vsc; 483 484 vser = VIRTIO_SERIAL(vdev); 485 port = find_port_by_vq(vser, vq); 486 487 if (!port) { 488 return; 489 } 490 vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); 491 492 /* 493 * If guest_connected is false, this call is being made by the 494 * early-boot queueing up of descriptors, which is just noise for 495 * the host apps -- don't disturb them in that case. 496 */ 497 if (port->guest_connected && port->host_connected && vsc->guest_writable) { 498 vsc->guest_writable(port); 499 } 500 } 501 502 static uint64_t get_features(VirtIODevice *vdev, uint64_t features) 503 { 504 VirtIOSerial *vser; 505 506 vser = VIRTIO_SERIAL(vdev); 507 508 if (vser->bus.max_nr_ports > 1) { 509 virtio_add_feature(&features, VIRTIO_CONSOLE_F_MULTIPORT); 510 } 511 return features; 512 } 513 514 /* Guest requested config info */ 515 static void get_config(VirtIODevice *vdev, uint8_t *config_data) 516 { 517 VirtIOSerial *vser = VIRTIO_SERIAL(vdev); 518 struct virtio_console_config *config = 519 (struct virtio_console_config *)config_data; 520 521 config->cols = 0; 522 config->rows = 0; 523 config->max_nr_ports = virtio_tswap32(vdev, 524 vser->serial.max_virtserial_ports); 525 } 526 527 static void guest_reset(VirtIOSerial *vser) 528 { 529 VirtIOSerialPort *port; 530 VirtIOSerialPortClass *vsc; 531 532 QTAILQ_FOREACH(port, &vser->ports, next) { 533 vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); 534 if (port->guest_connected) { 535 port->guest_connected = false; 536 if (vsc->set_guest_connected) { 537 vsc->set_guest_connected(port, false); 538 } 539 } 540 } 541 } 542 543 static void set_status(VirtIODevice *vdev, uint8_t status) 544 { 545 VirtIOSerial *vser; 546 VirtIOSerialPort *port; 547 548 vser = VIRTIO_SERIAL(vdev); 549 port = find_port_by_id(vser, 0); 550 551 if (port && !use_multiport(port->vser) 552 && (status & VIRTIO_CONFIG_S_DRIVER_OK)) { 553 /* 554 * Non-multiport guests won't be able to tell us guest 555 * open/close status. Such guests can only have a port at id 556 * 0, so set guest_connected for such ports as soon as guest 557 * is up. 558 */ 559 port->guest_connected = true; 560 } 561 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) { 562 guest_reset(vser); 563 } 564 } 565 566 static void vser_reset(VirtIODevice *vdev) 567 { 568 VirtIOSerial *vser; 569 570 vser = VIRTIO_SERIAL(vdev); 571 guest_reset(vser); 572 } 573 574 static void virtio_serial_save(QEMUFile *f, void *opaque) 575 { 576 /* The virtio device */ 577 virtio_save(VIRTIO_DEVICE(opaque), f); 578 } 579 580 static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f) 581 { 582 VirtIOSerial *s = VIRTIO_SERIAL(vdev); 583 VirtIOSerialPort *port; 584 uint32_t nr_active_ports; 585 unsigned int i, max_nr_ports; 586 struct virtio_console_config config; 587 588 /* The config space (ignored on the far end in current versions) */ 589 get_config(vdev, (uint8_t *)&config); 590 qemu_put_be16s(f, &config.cols); 591 qemu_put_be16s(f, &config.rows); 592 qemu_put_be32s(f, &config.max_nr_ports); 593 594 /* The ports map */ 595 max_nr_ports = s->serial.max_virtserial_ports; 596 for (i = 0; i < (max_nr_ports + 31) / 32; i++) { 597 qemu_put_be32s(f, &s->ports_map[i]); 598 } 599 600 /* Ports */ 601 602 nr_active_ports = 0; 603 QTAILQ_FOREACH(port, &s->ports, next) { 604 nr_active_ports++; 605 } 606 607 qemu_put_be32s(f, &nr_active_ports); 608 609 /* 610 * Items in struct VirtIOSerialPort. 611 */ 612 QTAILQ_FOREACH(port, &s->ports, next) { 613 uint32_t elem_popped; 614 615 qemu_put_be32s(f, &port->id); 616 qemu_put_byte(f, port->guest_connected); 617 qemu_put_byte(f, port->host_connected); 618 619 elem_popped = 0; 620 if (port->elem.out_num) { 621 elem_popped = 1; 622 } 623 qemu_put_be32s(f, &elem_popped); 624 if (elem_popped) { 625 qemu_put_be32s(f, &port->iov_idx); 626 qemu_put_be64s(f, &port->iov_offset); 627 628 qemu_put_buffer(f, (unsigned char *)&port->elem, 629 sizeof(port->elem)); 630 } 631 } 632 } 633 634 static void virtio_serial_post_load_timer_cb(void *opaque) 635 { 636 uint32_t i; 637 VirtIOSerial *s = VIRTIO_SERIAL(opaque); 638 VirtIOSerialPort *port; 639 uint8_t host_connected; 640 VirtIOSerialPortClass *vsc; 641 642 if (!s->post_load) { 643 return; 644 } 645 for (i = 0 ; i < s->post_load->nr_active_ports; ++i) { 646 port = s->post_load->connected[i].port; 647 host_connected = s->post_load->connected[i].host_connected; 648 if (host_connected != port->host_connected) { 649 /* 650 * We have to let the guest know of the host connection 651 * status change 652 */ 653 send_control_event(s, port->id, VIRTIO_CONSOLE_PORT_OPEN, 654 port->host_connected); 655 } 656 vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); 657 if (vsc->set_guest_connected) { 658 vsc->set_guest_connected(port, port->guest_connected); 659 } 660 } 661 g_free(s->post_load->connected); 662 timer_free(s->post_load->timer); 663 g_free(s->post_load); 664 s->post_load = NULL; 665 } 666 667 static int fetch_active_ports_list(QEMUFile *f, int version_id, 668 VirtIOSerial *s, uint32_t nr_active_ports) 669 { 670 uint32_t i; 671 672 s->post_load = g_malloc0(sizeof(*s->post_load)); 673 s->post_load->nr_active_ports = nr_active_ports; 674 s->post_load->connected = 675 g_malloc0(sizeof(*s->post_load->connected) * nr_active_ports); 676 677 s->post_load->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, 678 virtio_serial_post_load_timer_cb, 679 s); 680 681 /* Items in struct VirtIOSerialPort */ 682 for (i = 0; i < nr_active_ports; i++) { 683 VirtIOSerialPort *port; 684 uint32_t id; 685 686 id = qemu_get_be32(f); 687 port = find_port_by_id(s, id); 688 if (!port) { 689 return -EINVAL; 690 } 691 692 port->guest_connected = qemu_get_byte(f); 693 s->post_load->connected[i].port = port; 694 s->post_load->connected[i].host_connected = qemu_get_byte(f); 695 696 if (version_id > 2) { 697 uint32_t elem_popped; 698 699 qemu_get_be32s(f, &elem_popped); 700 if (elem_popped) { 701 qemu_get_be32s(f, &port->iov_idx); 702 qemu_get_be64s(f, &port->iov_offset); 703 704 qemu_get_buffer(f, (unsigned char *)&port->elem, 705 sizeof(port->elem)); 706 virtqueue_map_sg(port->elem.in_sg, port->elem.in_addr, 707 port->elem.in_num, 1); 708 virtqueue_map_sg(port->elem.out_sg, port->elem.out_addr, 709 port->elem.out_num, 1); 710 711 /* 712 * Port was throttled on source machine. Let's 713 * unthrottle it here so data starts flowing again. 714 */ 715 virtio_serial_throttle_port(port, false); 716 } 717 } 718 } 719 timer_mod(s->post_load->timer, 1); 720 return 0; 721 } 722 723 static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id) 724 { 725 if (version_id > 3) { 726 return -EINVAL; 727 } 728 729 /* The virtio device */ 730 return virtio_load(VIRTIO_DEVICE(opaque), f, version_id); 731 } 732 733 static int virtio_serial_load_device(VirtIODevice *vdev, QEMUFile *f, 734 int version_id) 735 { 736 VirtIOSerial *s = VIRTIO_SERIAL(vdev); 737 uint32_t max_nr_ports, nr_active_ports, ports_map; 738 unsigned int i; 739 int ret; 740 uint32_t tmp; 741 742 if (version_id < 2) { 743 return 0; 744 } 745 746 /* Unused */ 747 qemu_get_be16s(f, (uint16_t *) &tmp); 748 qemu_get_be16s(f, (uint16_t *) &tmp); 749 qemu_get_be32s(f, &tmp); 750 751 max_nr_ports = s->serial.max_virtserial_ports; 752 for (i = 0; i < (max_nr_ports + 31) / 32; i++) { 753 qemu_get_be32s(f, &ports_map); 754 755 if (ports_map != s->ports_map[i]) { 756 /* 757 * Ports active on source and destination don't 758 * match. Fail migration. 759 */ 760 return -EINVAL; 761 } 762 } 763 764 qemu_get_be32s(f, &nr_active_ports); 765 766 if (nr_active_ports) { 767 ret = fetch_active_ports_list(f, version_id, s, nr_active_ports); 768 if (ret) { 769 return ret; 770 } 771 } 772 return 0; 773 } 774 775 static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent); 776 777 static Property virtser_props[] = { 778 DEFINE_PROP_UINT32("nr", VirtIOSerialPort, id, VIRTIO_CONSOLE_BAD_ID), 779 DEFINE_PROP_STRING("name", VirtIOSerialPort, name), 780 DEFINE_PROP_END_OF_LIST() 781 }; 782 783 #define TYPE_VIRTIO_SERIAL_BUS "virtio-serial-bus" 784 #define VIRTIO_SERIAL_BUS(obj) \ 785 OBJECT_CHECK(VirtIOSerialBus, (obj), TYPE_VIRTIO_SERIAL_BUS) 786 787 static void virtser_bus_class_init(ObjectClass *klass, void *data) 788 { 789 BusClass *k = BUS_CLASS(klass); 790 k->print_dev = virtser_bus_dev_print; 791 } 792 793 static const TypeInfo virtser_bus_info = { 794 .name = TYPE_VIRTIO_SERIAL_BUS, 795 .parent = TYPE_BUS, 796 .instance_size = sizeof(VirtIOSerialBus), 797 .class_init = virtser_bus_class_init, 798 }; 799 800 static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent) 801 { 802 VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev); 803 804 monitor_printf(mon, "%*sport %d, guest %s, host %s, throttle %s\n", 805 indent, "", port->id, 806 port->guest_connected ? "on" : "off", 807 port->host_connected ? "on" : "off", 808 port->throttled ? "on" : "off"); 809 } 810 811 /* This function is only used if a port id is not provided by the user */ 812 static uint32_t find_free_port_id(VirtIOSerial *vser) 813 { 814 unsigned int i, max_nr_ports; 815 816 max_nr_ports = vser->serial.max_virtserial_ports; 817 for (i = 0; i < (max_nr_ports + 31) / 32; i++) { 818 uint32_t map, zeroes; 819 820 map = vser->ports_map[i]; 821 zeroes = ctz32(~map); 822 if (zeroes != 32) { 823 return zeroes + i * 32; 824 } 825 } 826 return VIRTIO_CONSOLE_BAD_ID; 827 } 828 829 static void mark_port_added(VirtIOSerial *vser, uint32_t port_id) 830 { 831 unsigned int i; 832 833 i = port_id / 32; 834 vser->ports_map[i] |= 1U << (port_id % 32); 835 } 836 837 static void add_port(VirtIOSerial *vser, uint32_t port_id) 838 { 839 mark_port_added(vser, port_id); 840 send_control_event(vser, port_id, VIRTIO_CONSOLE_PORT_ADD, 1); 841 } 842 843 static void remove_port(VirtIOSerial *vser, uint32_t port_id) 844 { 845 VirtIOSerialPort *port; 846 847 /* 848 * Don't mark port 0 removed -- we explicitly reserve it for 849 * backward compat with older guests, ensure a virtconsole device 850 * unplug retains the reservation. 851 */ 852 if (port_id) { 853 unsigned int i; 854 855 i = port_id / 32; 856 vser->ports_map[i] &= ~(1U << (port_id % 32)); 857 } 858 859 port = find_port_by_id(vser, port_id); 860 /* 861 * This function is only called from qdev's unplug callback; if we 862 * get a NULL port here, we're in trouble. 863 */ 864 assert(port); 865 866 /* Flush out any unconsumed buffers first */ 867 discard_vq_data(port->ovq, VIRTIO_DEVICE(port->vser)); 868 869 send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_REMOVE, 1); 870 } 871 872 static void virtser_port_device_realize(DeviceState *dev, Error **errp) 873 { 874 VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev); 875 VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); 876 VirtIOSerialBus *bus = VIRTIO_SERIAL_BUS(qdev_get_parent_bus(dev)); 877 int max_nr_ports; 878 bool plugging_port0; 879 Error *err = NULL; 880 881 port->vser = bus->vser; 882 port->bh = qemu_bh_new(flush_queued_data_bh, port); 883 884 assert(vsc->have_data); 885 886 /* 887 * Is the first console port we're seeing? If so, put it up at 888 * location 0. This is done for backward compatibility (old 889 * kernel, new qemu). 890 */ 891 plugging_port0 = vsc->is_console && !find_port_by_id(port->vser, 0); 892 893 if (find_port_by_id(port->vser, port->id)) { 894 error_setg(errp, "virtio-serial-bus: A port already exists at id %u", 895 port->id); 896 return; 897 } 898 899 if (port->name != NULL && find_port_by_name(port->name)) { 900 error_setg(errp, "virtio-serial-bus: A port already exists by name %s", 901 port->name); 902 return; 903 } 904 905 if (port->id == VIRTIO_CONSOLE_BAD_ID) { 906 if (plugging_port0) { 907 port->id = 0; 908 } else { 909 port->id = find_free_port_id(port->vser); 910 if (port->id == VIRTIO_CONSOLE_BAD_ID) { 911 error_setg(errp, "virtio-serial-bus: Maximum port limit for " 912 "this device reached"); 913 return; 914 } 915 } 916 } 917 918 max_nr_ports = port->vser->serial.max_virtserial_ports; 919 if (port->id >= max_nr_ports) { 920 error_setg(errp, "virtio-serial-bus: Out-of-range port id specified, " 921 "max. allowed: %u", max_nr_ports - 1); 922 return; 923 } 924 925 vsc->realize(dev, &err); 926 if (err != NULL) { 927 error_propagate(errp, err); 928 return; 929 } 930 931 port->elem.out_num = 0; 932 } 933 934 static void virtser_port_device_plug(HotplugHandler *hotplug_dev, 935 DeviceState *dev, Error **errp) 936 { 937 VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev); 938 939 QTAILQ_INSERT_TAIL(&port->vser->ports, port, next); 940 port->ivq = port->vser->ivqs[port->id]; 941 port->ovq = port->vser->ovqs[port->id]; 942 943 add_port(port->vser, port->id); 944 945 /* Send an update to the guest about this new port added */ 946 virtio_notify_config(VIRTIO_DEVICE(hotplug_dev)); 947 } 948 949 static void virtser_port_device_unrealize(DeviceState *dev, Error **errp) 950 { 951 VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev); 952 VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(dev); 953 VirtIOSerial *vser = port->vser; 954 955 qemu_bh_delete(port->bh); 956 remove_port(port->vser, port->id); 957 958 QTAILQ_REMOVE(&vser->ports, port, next); 959 960 if (vsc->unrealize) { 961 vsc->unrealize(dev, errp); 962 } 963 } 964 965 static void virtio_serial_device_realize(DeviceState *dev, Error **errp) 966 { 967 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 968 VirtIOSerial *vser = VIRTIO_SERIAL(dev); 969 uint32_t i, max_supported_ports; 970 971 if (!vser->serial.max_virtserial_ports) { 972 error_setg(errp, "Maximum number of serial ports not specified"); 973 return; 974 } 975 976 /* Each port takes 2 queues, and one pair is for the control queue */ 977 max_supported_ports = VIRTIO_QUEUE_MAX / 2 - 1; 978 979 if (vser->serial.max_virtserial_ports > max_supported_ports) { 980 error_setg(errp, "maximum ports supported: %u", max_supported_ports); 981 return; 982 } 983 984 /* We don't support emergency write, skip it for now. */ 985 /* TODO: cleaner fix, depending on host features. */ 986 virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE, 987 offsetof(struct virtio_console_config, emerg_wr)); 988 989 /* Spawn a new virtio-serial bus on which the ports will ride as devices */ 990 qbus_create_inplace(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS, 991 dev, vdev->bus_name); 992 qbus_set_hotplug_handler(BUS(&vser->bus), DEVICE(vser), errp); 993 vser->bus.vser = vser; 994 QTAILQ_INIT(&vser->ports); 995 996 vser->bus.max_nr_ports = vser->serial.max_virtserial_ports; 997 vser->ivqs = g_malloc(vser->serial.max_virtserial_ports 998 * sizeof(VirtQueue *)); 999 vser->ovqs = g_malloc(vser->serial.max_virtserial_ports 1000 * sizeof(VirtQueue *)); 1001 1002 /* Add a queue for host to guest transfers for port 0 (backward compat) */ 1003 vser->ivqs[0] = virtio_add_queue(vdev, 128, handle_input); 1004 /* Add a queue for guest to host transfers for port 0 (backward compat) */ 1005 vser->ovqs[0] = virtio_add_queue(vdev, 128, handle_output); 1006 1007 /* TODO: host to guest notifications can get dropped 1008 * if the queue fills up. Implement queueing in host, 1009 * this might also make it possible to reduce the control 1010 * queue size: as guest preposts buffers there, 1011 * this will save 4Kbyte of guest memory per entry. */ 1012 1013 /* control queue: host to guest */ 1014 vser->c_ivq = virtio_add_queue(vdev, 32, control_in); 1015 /* control queue: guest to host */ 1016 vser->c_ovq = virtio_add_queue(vdev, 32, control_out); 1017 1018 for (i = 1; i < vser->bus.max_nr_ports; i++) { 1019 /* Add a per-port queue for host to guest transfers */ 1020 vser->ivqs[i] = virtio_add_queue(vdev, 128, handle_input); 1021 /* Add a per-per queue for guest to host transfers */ 1022 vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output); 1023 } 1024 1025 vser->ports_map = g_malloc0(((vser->serial.max_virtserial_ports + 31) / 32) 1026 * sizeof(vser->ports_map[0])); 1027 /* 1028 * Reserve location 0 for a console port for backward compat 1029 * (old kernel, new qemu) 1030 */ 1031 mark_port_added(vser, 0); 1032 1033 vser->post_load = NULL; 1034 1035 /* 1036 * Register for the savevm section with the virtio-console name 1037 * to preserve backward compat 1038 */ 1039 register_savevm(dev, "virtio-console", -1, 3, virtio_serial_save, 1040 virtio_serial_load, vser); 1041 1042 QLIST_INSERT_HEAD(&vserdevices.devices, vser, next); 1043 } 1044 1045 static void virtio_serial_port_class_init(ObjectClass *klass, void *data) 1046 { 1047 DeviceClass *k = DEVICE_CLASS(klass); 1048 1049 set_bit(DEVICE_CATEGORY_INPUT, k->categories); 1050 k->bus_type = TYPE_VIRTIO_SERIAL_BUS; 1051 k->realize = virtser_port_device_realize; 1052 k->unrealize = virtser_port_device_unrealize; 1053 k->props = virtser_props; 1054 } 1055 1056 static const TypeInfo virtio_serial_port_type_info = { 1057 .name = TYPE_VIRTIO_SERIAL_PORT, 1058 .parent = TYPE_DEVICE, 1059 .instance_size = sizeof(VirtIOSerialPort), 1060 .abstract = true, 1061 .class_size = sizeof(VirtIOSerialPortClass), 1062 .class_init = virtio_serial_port_class_init, 1063 }; 1064 1065 static void virtio_serial_device_unrealize(DeviceState *dev, Error **errp) 1066 { 1067 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1068 VirtIOSerial *vser = VIRTIO_SERIAL(dev); 1069 1070 QLIST_REMOVE(vser, next); 1071 1072 unregister_savevm(dev, "virtio-console", vser); 1073 1074 g_free(vser->ivqs); 1075 g_free(vser->ovqs); 1076 g_free(vser->ports_map); 1077 if (vser->post_load) { 1078 g_free(vser->post_load->connected); 1079 timer_del(vser->post_load->timer); 1080 timer_free(vser->post_load->timer); 1081 g_free(vser->post_load); 1082 } 1083 virtio_cleanup(vdev); 1084 } 1085 1086 static Property virtio_serial_properties[] = { 1087 DEFINE_PROP_UINT32("max_ports", VirtIOSerial, serial.max_virtserial_ports, 1088 31), 1089 DEFINE_PROP_END_OF_LIST(), 1090 }; 1091 1092 static void virtio_serial_class_init(ObjectClass *klass, void *data) 1093 { 1094 DeviceClass *dc = DEVICE_CLASS(klass); 1095 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 1096 HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass); 1097 1098 QLIST_INIT(&vserdevices.devices); 1099 1100 dc->props = virtio_serial_properties; 1101 set_bit(DEVICE_CATEGORY_INPUT, dc->categories); 1102 vdc->realize = virtio_serial_device_realize; 1103 vdc->unrealize = virtio_serial_device_unrealize; 1104 vdc->get_features = get_features; 1105 vdc->get_config = get_config; 1106 vdc->set_status = set_status; 1107 vdc->reset = vser_reset; 1108 vdc->save = virtio_serial_save_device; 1109 vdc->load = virtio_serial_load_device; 1110 hc->plug = virtser_port_device_plug; 1111 hc->unplug = qdev_simple_device_unplug_cb; 1112 } 1113 1114 static const TypeInfo virtio_device_info = { 1115 .name = TYPE_VIRTIO_SERIAL, 1116 .parent = TYPE_VIRTIO_DEVICE, 1117 .instance_size = sizeof(VirtIOSerial), 1118 .class_init = virtio_serial_class_init, 1119 .interfaces = (InterfaceInfo[]) { 1120 { TYPE_HOTPLUG_HANDLER }, 1121 { } 1122 } 1123 }; 1124 1125 static void virtio_serial_register_types(void) 1126 { 1127 type_register_static(&virtser_bus_info); 1128 type_register_static(&virtio_serial_port_type_info); 1129 type_register_static(&virtio_device_info); 1130 } 1131 1132 type_init(virtio_serial_register_types) 1133