1 /* 2 * QEMU System Emulator 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * Copyright (c) 2009-2015 Red Hat Inc 6 * 7 * Authors: 8 * Juan Quintela <quintela@redhat.com> 9 * 10 * Permission is hereby granted, free of charge, to any person obtaining a copy 11 * of this software and associated documentation files (the "Software"), to deal 12 * in the Software without restriction, including without limitation the rights 13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 14 * copies of the Software, and to permit persons to whom the Software is 15 * furnished to do so, subject to the following conditions: 16 * 17 * The above copyright notice and this permission notice shall be included in 18 * all copies or substantial portions of the Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 26 * THE SOFTWARE. 27 */ 28 29 #include "config-host.h" 30 #include "qemu-common.h" 31 #include "hw/boards.h" 32 #include "hw/hw.h" 33 #include "hw/qdev.h" 34 #include "net/net.h" 35 #include "monitor/monitor.h" 36 #include "sysemu/sysemu.h" 37 #include "qemu/timer.h" 38 #include "audio/audio.h" 39 #include "migration/migration.h" 40 #include "migration/postcopy-ram.h" 41 #include "qapi/qmp/qerror.h" 42 #include "qemu/error-report.h" 43 #include "qemu/sockets.h" 44 #include "qemu/queue.h" 45 #include "sysemu/cpus.h" 46 #include "exec/memory.h" 47 #include "qmp-commands.h" 48 #include "trace.h" 49 #include "qemu/bitops.h" 50 #include "qemu/iov.h" 51 #include "block/snapshot.h" 52 #include "block/qapi.h" 53 54 55 #ifndef ETH_P_RARP 56 #define ETH_P_RARP 0x8035 57 #endif 58 #define ARP_HTYPE_ETH 0x0001 59 #define ARP_PTYPE_IP 0x0800 60 #define ARP_OP_REQUEST_REV 0x3 61 62 const unsigned int postcopy_ram_discard_version = 0; 63 64 static bool skip_section_footers; 65 66 static struct mig_cmd_args { 67 ssize_t len; /* -1 = variable */ 68 const char *name; 69 } mig_cmd_args[] = { 70 [MIG_CMD_INVALID] = { .len = -1, .name = "INVALID" }, 71 [MIG_CMD_OPEN_RETURN_PATH] = { .len = 0, .name = "OPEN_RETURN_PATH" }, 72 [MIG_CMD_PING] = { .len = sizeof(uint32_t), .name = "PING" }, 73 [MIG_CMD_POSTCOPY_ADVISE] = { .len = 16, .name = "POSTCOPY_ADVISE" }, 74 [MIG_CMD_POSTCOPY_LISTEN] = { .len = 0, .name = "POSTCOPY_LISTEN" }, 75 [MIG_CMD_POSTCOPY_RUN] = { .len = 0, .name = "POSTCOPY_RUN" }, 76 [MIG_CMD_POSTCOPY_RAM_DISCARD] = { 77 .len = -1, .name = "POSTCOPY_RAM_DISCARD" }, 78 [MIG_CMD_PACKAGED] = { .len = 4, .name = "PACKAGED" }, 79 [MIG_CMD_MAX] = { .len = -1, .name = "MAX" }, 80 }; 81 82 static int announce_self_create(uint8_t *buf, 83 uint8_t *mac_addr) 84 { 85 /* Ethernet header. */ 86 memset(buf, 0xff, 6); /* destination MAC addr */ 87 memcpy(buf + 6, mac_addr, 6); /* source MAC addr */ 88 *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */ 89 90 /* RARP header. */ 91 *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */ 92 *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */ 93 *(buf + 18) = 6; /* hardware addr length (ethernet) */ 94 *(buf + 19) = 4; /* protocol addr length (IPv4) */ 95 *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */ 96 memcpy(buf + 22, mac_addr, 6); /* source hw addr */ 97 memset(buf + 28, 0x00, 4); /* source protocol addr */ 98 memcpy(buf + 32, mac_addr, 6); /* target hw addr */ 99 memset(buf + 38, 0x00, 4); /* target protocol addr */ 100 101 /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */ 102 memset(buf + 42, 0x00, 18); 103 104 return 60; /* len (FCS will be added by hardware) */ 105 } 106 107 static void qemu_announce_self_iter(NICState *nic, void *opaque) 108 { 109 uint8_t buf[60]; 110 int len; 111 112 trace_qemu_announce_self_iter(qemu_ether_ntoa(&nic->conf->macaddr)); 113 len = announce_self_create(buf, nic->conf->macaddr.a); 114 115 qemu_send_packet_raw(qemu_get_queue(nic), buf, len); 116 } 117 118 119 static void qemu_announce_self_once(void *opaque) 120 { 121 static int count = SELF_ANNOUNCE_ROUNDS; 122 QEMUTimer *timer = *(QEMUTimer **)opaque; 123 124 qemu_foreach_nic(qemu_announce_self_iter, NULL); 125 126 if (--count) { 127 /* delay 50ms, 150ms, 250ms, ... */ 128 timer_mod(timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 129 self_announce_delay(count)); 130 } else { 131 timer_del(timer); 132 timer_free(timer); 133 } 134 } 135 136 void qemu_announce_self(void) 137 { 138 static QEMUTimer *timer; 139 timer = timer_new_ms(QEMU_CLOCK_REALTIME, qemu_announce_self_once, &timer); 140 qemu_announce_self_once(&timer); 141 } 142 143 /***********************************************************/ 144 /* savevm/loadvm support */ 145 146 static ssize_t block_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, 147 int64_t pos) 148 { 149 int ret; 150 QEMUIOVector qiov; 151 152 qemu_iovec_init_external(&qiov, iov, iovcnt); 153 ret = bdrv_writev_vmstate(opaque, &qiov, pos); 154 if (ret < 0) { 155 return ret; 156 } 157 158 return qiov.size; 159 } 160 161 static ssize_t block_put_buffer(void *opaque, const uint8_t *buf, 162 int64_t pos, size_t size) 163 { 164 bdrv_save_vmstate(opaque, buf, pos, size); 165 return size; 166 } 167 168 static ssize_t block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, 169 size_t size) 170 { 171 return bdrv_load_vmstate(opaque, buf, pos, size); 172 } 173 174 static int bdrv_fclose(void *opaque) 175 { 176 return bdrv_flush(opaque); 177 } 178 179 static const QEMUFileOps bdrv_read_ops = { 180 .get_buffer = block_get_buffer, 181 .close = bdrv_fclose 182 }; 183 184 static const QEMUFileOps bdrv_write_ops = { 185 .put_buffer = block_put_buffer, 186 .writev_buffer = block_writev_buffer, 187 .close = bdrv_fclose 188 }; 189 190 static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable) 191 { 192 if (is_writable) { 193 return qemu_fopen_ops(bs, &bdrv_write_ops); 194 } 195 return qemu_fopen_ops(bs, &bdrv_read_ops); 196 } 197 198 199 /* QEMUFile timer support. 200 * Not in qemu-file.c to not add qemu-timer.c as dependency to qemu-file.c 201 */ 202 203 void timer_put(QEMUFile *f, QEMUTimer *ts) 204 { 205 uint64_t expire_time; 206 207 expire_time = timer_expire_time_ns(ts); 208 qemu_put_be64(f, expire_time); 209 } 210 211 void timer_get(QEMUFile *f, QEMUTimer *ts) 212 { 213 uint64_t expire_time; 214 215 expire_time = qemu_get_be64(f); 216 if (expire_time != -1) { 217 timer_mod_ns(ts, expire_time); 218 } else { 219 timer_del(ts); 220 } 221 } 222 223 224 /* VMState timer support. 225 * Not in vmstate.c to not add qemu-timer.c as dependency to vmstate.c 226 */ 227 228 static int get_timer(QEMUFile *f, void *pv, size_t size) 229 { 230 QEMUTimer *v = pv; 231 timer_get(f, v); 232 return 0; 233 } 234 235 static void put_timer(QEMUFile *f, void *pv, size_t size) 236 { 237 QEMUTimer *v = pv; 238 timer_put(f, v); 239 } 240 241 const VMStateInfo vmstate_info_timer = { 242 .name = "timer", 243 .get = get_timer, 244 .put = put_timer, 245 }; 246 247 248 typedef struct CompatEntry { 249 char idstr[256]; 250 int instance_id; 251 } CompatEntry; 252 253 typedef struct SaveStateEntry { 254 QTAILQ_ENTRY(SaveStateEntry) entry; 255 char idstr[256]; 256 int instance_id; 257 int alias_id; 258 int version_id; 259 int section_id; 260 SaveVMHandlers *ops; 261 const VMStateDescription *vmsd; 262 void *opaque; 263 CompatEntry *compat; 264 int is_ram; 265 } SaveStateEntry; 266 267 typedef struct SaveState { 268 QTAILQ_HEAD(, SaveStateEntry) handlers; 269 int global_section_id; 270 bool skip_configuration; 271 uint32_t len; 272 const char *name; 273 } SaveState; 274 275 static SaveState savevm_state = { 276 .handlers = QTAILQ_HEAD_INITIALIZER(savevm_state.handlers), 277 .global_section_id = 0, 278 .skip_configuration = false, 279 }; 280 281 void savevm_skip_configuration(void) 282 { 283 savevm_state.skip_configuration = true; 284 } 285 286 287 static void configuration_pre_save(void *opaque) 288 { 289 SaveState *state = opaque; 290 const char *current_name = MACHINE_GET_CLASS(current_machine)->name; 291 292 state->len = strlen(current_name); 293 state->name = current_name; 294 } 295 296 static int configuration_post_load(void *opaque, int version_id) 297 { 298 SaveState *state = opaque; 299 const char *current_name = MACHINE_GET_CLASS(current_machine)->name; 300 301 if (strncmp(state->name, current_name, state->len) != 0) { 302 error_report("Machine type received is '%s' and local is '%s'", 303 state->name, current_name); 304 return -EINVAL; 305 } 306 return 0; 307 } 308 309 static const VMStateDescription vmstate_configuration = { 310 .name = "configuration", 311 .version_id = 1, 312 .post_load = configuration_post_load, 313 .pre_save = configuration_pre_save, 314 .fields = (VMStateField[]) { 315 VMSTATE_UINT32(len, SaveState), 316 VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, 0, len), 317 VMSTATE_END_OF_LIST() 318 }, 319 }; 320 321 static void dump_vmstate_vmsd(FILE *out_file, 322 const VMStateDescription *vmsd, int indent, 323 bool is_subsection); 324 325 static void dump_vmstate_vmsf(FILE *out_file, const VMStateField *field, 326 int indent) 327 { 328 fprintf(out_file, "%*s{\n", indent, ""); 329 indent += 2; 330 fprintf(out_file, "%*s\"field\": \"%s\",\n", indent, "", field->name); 331 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 332 field->version_id); 333 fprintf(out_file, "%*s\"field_exists\": %s,\n", indent, "", 334 field->field_exists ? "true" : "false"); 335 fprintf(out_file, "%*s\"size\": %zu", indent, "", field->size); 336 if (field->vmsd != NULL) { 337 fprintf(out_file, ",\n"); 338 dump_vmstate_vmsd(out_file, field->vmsd, indent, false); 339 } 340 fprintf(out_file, "\n%*s}", indent - 2, ""); 341 } 342 343 static void dump_vmstate_vmss(FILE *out_file, 344 const VMStateDescription **subsection, 345 int indent) 346 { 347 if (*subsection != NULL) { 348 dump_vmstate_vmsd(out_file, *subsection, indent, true); 349 } 350 } 351 352 static void dump_vmstate_vmsd(FILE *out_file, 353 const VMStateDescription *vmsd, int indent, 354 bool is_subsection) 355 { 356 if (is_subsection) { 357 fprintf(out_file, "%*s{\n", indent, ""); 358 } else { 359 fprintf(out_file, "%*s\"%s\": {\n", indent, "", "Description"); 360 } 361 indent += 2; 362 fprintf(out_file, "%*s\"name\": \"%s\",\n", indent, "", vmsd->name); 363 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 364 vmsd->version_id); 365 fprintf(out_file, "%*s\"minimum_version_id\": %d", indent, "", 366 vmsd->minimum_version_id); 367 if (vmsd->fields != NULL) { 368 const VMStateField *field = vmsd->fields; 369 bool first; 370 371 fprintf(out_file, ",\n%*s\"Fields\": [\n", indent, ""); 372 first = true; 373 while (field->name != NULL) { 374 if (field->flags & VMS_MUST_EXIST) { 375 /* Ignore VMSTATE_VALIDATE bits; these don't get migrated */ 376 field++; 377 continue; 378 } 379 if (!first) { 380 fprintf(out_file, ",\n"); 381 } 382 dump_vmstate_vmsf(out_file, field, indent + 2); 383 field++; 384 first = false; 385 } 386 fprintf(out_file, "\n%*s]", indent, ""); 387 } 388 if (vmsd->subsections != NULL) { 389 const VMStateDescription **subsection = vmsd->subsections; 390 bool first; 391 392 fprintf(out_file, ",\n%*s\"Subsections\": [\n", indent, ""); 393 first = true; 394 while (*subsection != NULL) { 395 if (!first) { 396 fprintf(out_file, ",\n"); 397 } 398 dump_vmstate_vmss(out_file, subsection, indent + 2); 399 subsection++; 400 first = false; 401 } 402 fprintf(out_file, "\n%*s]", indent, ""); 403 } 404 fprintf(out_file, "\n%*s}", indent - 2, ""); 405 } 406 407 static void dump_machine_type(FILE *out_file) 408 { 409 MachineClass *mc; 410 411 mc = MACHINE_GET_CLASS(current_machine); 412 413 fprintf(out_file, " \"vmschkmachine\": {\n"); 414 fprintf(out_file, " \"Name\": \"%s\"\n", mc->name); 415 fprintf(out_file, " },\n"); 416 } 417 418 void dump_vmstate_json_to_file(FILE *out_file) 419 { 420 GSList *list, *elt; 421 bool first; 422 423 fprintf(out_file, "{\n"); 424 dump_machine_type(out_file); 425 426 first = true; 427 list = object_class_get_list(TYPE_DEVICE, true); 428 for (elt = list; elt; elt = elt->next) { 429 DeviceClass *dc = OBJECT_CLASS_CHECK(DeviceClass, elt->data, 430 TYPE_DEVICE); 431 const char *name; 432 int indent = 2; 433 434 if (!dc->vmsd) { 435 continue; 436 } 437 438 if (!first) { 439 fprintf(out_file, ",\n"); 440 } 441 name = object_class_get_name(OBJECT_CLASS(dc)); 442 fprintf(out_file, "%*s\"%s\": {\n", indent, "", name); 443 indent += 2; 444 fprintf(out_file, "%*s\"Name\": \"%s\",\n", indent, "", name); 445 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 446 dc->vmsd->version_id); 447 fprintf(out_file, "%*s\"minimum_version_id\": %d,\n", indent, "", 448 dc->vmsd->minimum_version_id); 449 450 dump_vmstate_vmsd(out_file, dc->vmsd, indent, false); 451 452 fprintf(out_file, "\n%*s}", indent - 2, ""); 453 first = false; 454 } 455 fprintf(out_file, "\n}\n"); 456 fclose(out_file); 457 } 458 459 static int calculate_new_instance_id(const char *idstr) 460 { 461 SaveStateEntry *se; 462 int instance_id = 0; 463 464 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 465 if (strcmp(idstr, se->idstr) == 0 466 && instance_id <= se->instance_id) { 467 instance_id = se->instance_id + 1; 468 } 469 } 470 return instance_id; 471 } 472 473 static int calculate_compat_instance_id(const char *idstr) 474 { 475 SaveStateEntry *se; 476 int instance_id = 0; 477 478 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 479 if (!se->compat) { 480 continue; 481 } 482 483 if (strcmp(idstr, se->compat->idstr) == 0 484 && instance_id <= se->compat->instance_id) { 485 instance_id = se->compat->instance_id + 1; 486 } 487 } 488 return instance_id; 489 } 490 491 /* TODO: Individual devices generally have very little idea about the rest 492 of the system, so instance_id should be removed/replaced. 493 Meanwhile pass -1 as instance_id if you do not already have a clearly 494 distinguishing id for all instances of your device class. */ 495 int register_savevm_live(DeviceState *dev, 496 const char *idstr, 497 int instance_id, 498 int version_id, 499 SaveVMHandlers *ops, 500 void *opaque) 501 { 502 SaveStateEntry *se; 503 504 se = g_new0(SaveStateEntry, 1); 505 se->version_id = version_id; 506 se->section_id = savevm_state.global_section_id++; 507 se->ops = ops; 508 se->opaque = opaque; 509 se->vmsd = NULL; 510 /* if this is a live_savem then set is_ram */ 511 if (ops->save_live_setup != NULL) { 512 se->is_ram = 1; 513 } 514 515 if (dev) { 516 char *id = qdev_get_dev_path(dev); 517 if (id) { 518 pstrcpy(se->idstr, sizeof(se->idstr), id); 519 pstrcat(se->idstr, sizeof(se->idstr), "/"); 520 g_free(id); 521 522 se->compat = g_new0(CompatEntry, 1); 523 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr); 524 se->compat->instance_id = instance_id == -1 ? 525 calculate_compat_instance_id(idstr) : instance_id; 526 instance_id = -1; 527 } 528 } 529 pstrcat(se->idstr, sizeof(se->idstr), idstr); 530 531 if (instance_id == -1) { 532 se->instance_id = calculate_new_instance_id(se->idstr); 533 } else { 534 se->instance_id = instance_id; 535 } 536 assert(!se->compat || se->instance_id == 0); 537 /* add at the end of list */ 538 QTAILQ_INSERT_TAIL(&savevm_state.handlers, se, entry); 539 return 0; 540 } 541 542 int register_savevm(DeviceState *dev, 543 const char *idstr, 544 int instance_id, 545 int version_id, 546 SaveStateHandler *save_state, 547 LoadStateHandler *load_state, 548 void *opaque) 549 { 550 SaveVMHandlers *ops = g_new0(SaveVMHandlers, 1); 551 ops->save_state = save_state; 552 ops->load_state = load_state; 553 return register_savevm_live(dev, idstr, instance_id, version_id, 554 ops, opaque); 555 } 556 557 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque) 558 { 559 SaveStateEntry *se, *new_se; 560 char id[256] = ""; 561 562 if (dev) { 563 char *path = qdev_get_dev_path(dev); 564 if (path) { 565 pstrcpy(id, sizeof(id), path); 566 pstrcat(id, sizeof(id), "/"); 567 g_free(path); 568 } 569 } 570 pstrcat(id, sizeof(id), idstr); 571 572 QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { 573 if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) { 574 QTAILQ_REMOVE(&savevm_state.handlers, se, entry); 575 g_free(se->compat); 576 g_free(se->ops); 577 g_free(se); 578 } 579 } 580 } 581 582 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id, 583 const VMStateDescription *vmsd, 584 void *opaque, int alias_id, 585 int required_for_version) 586 { 587 SaveStateEntry *se; 588 589 /* If this triggers, alias support can be dropped for the vmsd. */ 590 assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id); 591 592 se = g_new0(SaveStateEntry, 1); 593 se->version_id = vmsd->version_id; 594 se->section_id = savevm_state.global_section_id++; 595 se->opaque = opaque; 596 se->vmsd = vmsd; 597 se->alias_id = alias_id; 598 599 if (dev) { 600 char *id = qdev_get_dev_path(dev); 601 if (id) { 602 pstrcpy(se->idstr, sizeof(se->idstr), id); 603 pstrcat(se->idstr, sizeof(se->idstr), "/"); 604 g_free(id); 605 606 se->compat = g_new0(CompatEntry, 1); 607 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name); 608 se->compat->instance_id = instance_id == -1 ? 609 calculate_compat_instance_id(vmsd->name) : instance_id; 610 instance_id = -1; 611 } 612 } 613 pstrcat(se->idstr, sizeof(se->idstr), vmsd->name); 614 615 if (instance_id == -1) { 616 se->instance_id = calculate_new_instance_id(se->idstr); 617 } else { 618 se->instance_id = instance_id; 619 } 620 assert(!se->compat || se->instance_id == 0); 621 /* add at the end of list */ 622 QTAILQ_INSERT_TAIL(&savevm_state.handlers, se, entry); 623 return 0; 624 } 625 626 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd, 627 void *opaque) 628 { 629 SaveStateEntry *se, *new_se; 630 631 QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { 632 if (se->vmsd == vmsd && se->opaque == opaque) { 633 QTAILQ_REMOVE(&savevm_state.handlers, se, entry); 634 g_free(se->compat); 635 g_free(se); 636 } 637 } 638 } 639 640 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) 641 { 642 trace_vmstate_load(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); 643 if (!se->vmsd) { /* Old style */ 644 return se->ops->load_state(f, se->opaque, version_id); 645 } 646 return vmstate_load_state(f, se->vmsd, se->opaque, version_id); 647 } 648 649 static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) 650 { 651 int64_t old_offset, size; 652 653 old_offset = qemu_ftell_fast(f); 654 se->ops->save_state(f, se->opaque); 655 size = qemu_ftell_fast(f) - old_offset; 656 657 if (vmdesc) { 658 json_prop_int(vmdesc, "size", size); 659 json_start_array(vmdesc, "fields"); 660 json_start_object(vmdesc, NULL); 661 json_prop_str(vmdesc, "name", "data"); 662 json_prop_int(vmdesc, "size", size); 663 json_prop_str(vmdesc, "type", "buffer"); 664 json_end_object(vmdesc); 665 json_end_array(vmdesc); 666 } 667 } 668 669 static void vmstate_save(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) 670 { 671 trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); 672 if (!se->vmsd) { 673 vmstate_save_old_style(f, se, vmdesc); 674 return; 675 } 676 vmstate_save_state(f, se->vmsd, se->opaque, vmdesc); 677 } 678 679 void savevm_skip_section_footers(void) 680 { 681 skip_section_footers = true; 682 } 683 684 /* 685 * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL) 686 */ 687 static void save_section_header(QEMUFile *f, SaveStateEntry *se, 688 uint8_t section_type) 689 { 690 qemu_put_byte(f, section_type); 691 qemu_put_be32(f, se->section_id); 692 693 if (section_type == QEMU_VM_SECTION_FULL || 694 section_type == QEMU_VM_SECTION_START) { 695 /* ID string */ 696 size_t len = strlen(se->idstr); 697 qemu_put_byte(f, len); 698 qemu_put_buffer(f, (uint8_t *)se->idstr, len); 699 700 qemu_put_be32(f, se->instance_id); 701 qemu_put_be32(f, se->version_id); 702 } 703 } 704 705 /* 706 * Write a footer onto device sections that catches cases misformatted device 707 * sections. 708 */ 709 static void save_section_footer(QEMUFile *f, SaveStateEntry *se) 710 { 711 if (!skip_section_footers) { 712 qemu_put_byte(f, QEMU_VM_SECTION_FOOTER); 713 qemu_put_be32(f, se->section_id); 714 } 715 } 716 717 /** 718 * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the 719 * command and associated data. 720 * 721 * @f: File to send command on 722 * @command: Command type to send 723 * @len: Length of associated data 724 * @data: Data associated with command. 725 */ 726 void qemu_savevm_command_send(QEMUFile *f, 727 enum qemu_vm_cmd command, 728 uint16_t len, 729 uint8_t *data) 730 { 731 trace_savevm_command_send(command, len); 732 qemu_put_byte(f, QEMU_VM_COMMAND); 733 qemu_put_be16(f, (uint16_t)command); 734 qemu_put_be16(f, len); 735 qemu_put_buffer(f, data, len); 736 qemu_fflush(f); 737 } 738 739 void qemu_savevm_send_ping(QEMUFile *f, uint32_t value) 740 { 741 uint32_t buf; 742 743 trace_savevm_send_ping(value); 744 buf = cpu_to_be32(value); 745 qemu_savevm_command_send(f, MIG_CMD_PING, sizeof(value), (uint8_t *)&buf); 746 } 747 748 void qemu_savevm_send_open_return_path(QEMUFile *f) 749 { 750 trace_savevm_send_open_return_path(); 751 qemu_savevm_command_send(f, MIG_CMD_OPEN_RETURN_PATH, 0, NULL); 752 } 753 754 /* We have a buffer of data to send; we don't want that all to be loaded 755 * by the command itself, so the command contains just the length of the 756 * extra buffer that we then send straight after it. 757 * TODO: Must be a better way to organise that 758 * 759 * Returns: 760 * 0 on success 761 * -ve on error 762 */ 763 int qemu_savevm_send_packaged(QEMUFile *f, const QEMUSizedBuffer *qsb) 764 { 765 size_t cur_iov; 766 size_t len = qsb_get_length(qsb); 767 uint32_t tmp; 768 769 if (len > MAX_VM_CMD_PACKAGED_SIZE) { 770 error_report("%s: Unreasonably large packaged state: %zu", 771 __func__, len); 772 return -1; 773 } 774 775 tmp = cpu_to_be32(len); 776 777 trace_qemu_savevm_send_packaged(); 778 qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); 779 780 /* all the data follows (concatinating the iov's) */ 781 for (cur_iov = 0; cur_iov < qsb->n_iov; cur_iov++) { 782 /* The iov entries are partially filled */ 783 size_t towrite = MIN(qsb->iov[cur_iov].iov_len, len); 784 len -= towrite; 785 786 if (!towrite) { 787 break; 788 } 789 790 qemu_put_buffer(f, qsb->iov[cur_iov].iov_base, towrite); 791 } 792 793 return 0; 794 } 795 796 /* Send prior to any postcopy transfer */ 797 void qemu_savevm_send_postcopy_advise(QEMUFile *f) 798 { 799 uint64_t tmp[2]; 800 tmp[0] = cpu_to_be64(getpagesize()); 801 tmp[1] = cpu_to_be64(1ul << qemu_target_page_bits()); 802 803 trace_qemu_savevm_send_postcopy_advise(); 804 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_ADVISE, 16, (uint8_t *)tmp); 805 } 806 807 /* Sent prior to starting the destination running in postcopy, discard pages 808 * that have already been sent but redirtied on the source. 809 * CMD_POSTCOPY_RAM_DISCARD consist of: 810 * byte version (0) 811 * byte Length of name field (not including 0) 812 * n x byte RAM block name 813 * byte 0 terminator (just for safety) 814 * n x Byte ranges within the named RAMBlock 815 * be64 Start of the range 816 * be64 Length 817 * 818 * name: RAMBlock name that these entries are part of 819 * len: Number of page entries 820 * start_list: 'len' addresses 821 * length_list: 'len' addresses 822 * 823 */ 824 void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name, 825 uint16_t len, 826 uint64_t *start_list, 827 uint64_t *length_list) 828 { 829 uint8_t *buf; 830 uint16_t tmplen; 831 uint16_t t; 832 size_t name_len = strlen(name); 833 834 trace_qemu_savevm_send_postcopy_ram_discard(name, len); 835 assert(name_len < 256); 836 buf = g_malloc0(1 + 1 + name_len + 1 + (8 + 8) * len); 837 buf[0] = postcopy_ram_discard_version; 838 buf[1] = name_len; 839 memcpy(buf + 2, name, name_len); 840 tmplen = 2 + name_len; 841 buf[tmplen++] = '\0'; 842 843 for (t = 0; t < len; t++) { 844 cpu_to_be64w((uint64_t *)(buf + tmplen), start_list[t]); 845 tmplen += 8; 846 cpu_to_be64w((uint64_t *)(buf + tmplen), length_list[t]); 847 tmplen += 8; 848 } 849 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RAM_DISCARD, tmplen, buf); 850 g_free(buf); 851 } 852 853 /* Get the destination into a state where it can receive postcopy data. */ 854 void qemu_savevm_send_postcopy_listen(QEMUFile *f) 855 { 856 trace_savevm_send_postcopy_listen(); 857 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_LISTEN, 0, NULL); 858 } 859 860 /* Kick the destination into running */ 861 void qemu_savevm_send_postcopy_run(QEMUFile *f) 862 { 863 trace_savevm_send_postcopy_run(); 864 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RUN, 0, NULL); 865 } 866 867 bool qemu_savevm_state_blocked(Error **errp) 868 { 869 SaveStateEntry *se; 870 871 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 872 if (se->vmsd && se->vmsd->unmigratable) { 873 error_setg(errp, "State blocked by non-migratable device '%s'", 874 se->idstr); 875 return true; 876 } 877 } 878 return false; 879 } 880 881 void qemu_savevm_state_header(QEMUFile *f) 882 { 883 trace_savevm_state_header(); 884 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 885 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 886 887 if (!savevm_state.skip_configuration) { 888 qemu_put_byte(f, QEMU_VM_CONFIGURATION); 889 vmstate_save_state(f, &vmstate_configuration, &savevm_state, 0); 890 } 891 892 } 893 894 void qemu_savevm_state_begin(QEMUFile *f, 895 const MigrationParams *params) 896 { 897 SaveStateEntry *se; 898 int ret; 899 900 trace_savevm_state_begin(); 901 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 902 if (!se->ops || !se->ops->set_params) { 903 continue; 904 } 905 se->ops->set_params(params, se->opaque); 906 } 907 908 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 909 if (!se->ops || !se->ops->save_live_setup) { 910 continue; 911 } 912 if (se->ops && se->ops->is_active) { 913 if (!se->ops->is_active(se->opaque)) { 914 continue; 915 } 916 } 917 save_section_header(f, se, QEMU_VM_SECTION_START); 918 919 ret = se->ops->save_live_setup(f, se->opaque); 920 save_section_footer(f, se); 921 if (ret < 0) { 922 qemu_file_set_error(f, ret); 923 break; 924 } 925 } 926 } 927 928 /* 929 * this function has three return values: 930 * negative: there was one error, and we have -errno. 931 * 0 : We haven't finished, caller have to go again 932 * 1 : We have finished, we can go to complete phase 933 */ 934 int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy) 935 { 936 SaveStateEntry *se; 937 int ret = 1; 938 939 trace_savevm_state_iterate(); 940 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 941 if (!se->ops || !se->ops->save_live_iterate) { 942 continue; 943 } 944 if (se->ops && se->ops->is_active) { 945 if (!se->ops->is_active(se->opaque)) { 946 continue; 947 } 948 } 949 /* 950 * In the postcopy phase, any device that doesn't know how to 951 * do postcopy should have saved it's state in the _complete 952 * call that's already run, it might get confused if we call 953 * iterate afterwards. 954 */ 955 if (postcopy && !se->ops->save_live_complete_postcopy) { 956 continue; 957 } 958 if (qemu_file_rate_limit(f)) { 959 return 0; 960 } 961 trace_savevm_section_start(se->idstr, se->section_id); 962 963 save_section_header(f, se, QEMU_VM_SECTION_PART); 964 965 ret = se->ops->save_live_iterate(f, se->opaque); 966 trace_savevm_section_end(se->idstr, se->section_id, ret); 967 save_section_footer(f, se); 968 969 if (ret < 0) { 970 qemu_file_set_error(f, ret); 971 } 972 if (ret <= 0) { 973 /* Do not proceed to the next vmstate before this one reported 974 completion of the current stage. This serializes the migration 975 and reduces the probability that a faster changing state is 976 synchronized over and over again. */ 977 break; 978 } 979 } 980 return ret; 981 } 982 983 static bool should_send_vmdesc(void) 984 { 985 MachineState *machine = MACHINE(qdev_get_machine()); 986 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 987 return !machine->suppress_vmdesc && !in_postcopy; 988 } 989 990 /* 991 * Calls the save_live_complete_postcopy methods 992 * causing the last few pages to be sent immediately and doing any associated 993 * cleanup. 994 * Note postcopy also calls qemu_savevm_state_complete_precopy to complete 995 * all the other devices, but that happens at the point we switch to postcopy. 996 */ 997 void qemu_savevm_state_complete_postcopy(QEMUFile *f) 998 { 999 SaveStateEntry *se; 1000 int ret; 1001 1002 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1003 if (!se->ops || !se->ops->save_live_complete_postcopy) { 1004 continue; 1005 } 1006 if (se->ops && se->ops->is_active) { 1007 if (!se->ops->is_active(se->opaque)) { 1008 continue; 1009 } 1010 } 1011 trace_savevm_section_start(se->idstr, se->section_id); 1012 /* Section type */ 1013 qemu_put_byte(f, QEMU_VM_SECTION_END); 1014 qemu_put_be32(f, se->section_id); 1015 1016 ret = se->ops->save_live_complete_postcopy(f, se->opaque); 1017 trace_savevm_section_end(se->idstr, se->section_id, ret); 1018 save_section_footer(f, se); 1019 if (ret < 0) { 1020 qemu_file_set_error(f, ret); 1021 return; 1022 } 1023 } 1024 1025 qemu_put_byte(f, QEMU_VM_EOF); 1026 qemu_fflush(f); 1027 } 1028 1029 void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) 1030 { 1031 QJSON *vmdesc; 1032 int vmdesc_len; 1033 SaveStateEntry *se; 1034 int ret; 1035 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 1036 1037 trace_savevm_state_complete_precopy(); 1038 1039 cpu_synchronize_all_states(); 1040 1041 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1042 if (!se->ops || 1043 (in_postcopy && se->ops->save_live_complete_postcopy) || 1044 (in_postcopy && !iterable_only) || 1045 !se->ops->save_live_complete_precopy) { 1046 continue; 1047 } 1048 1049 if (se->ops && se->ops->is_active) { 1050 if (!se->ops->is_active(se->opaque)) { 1051 continue; 1052 } 1053 } 1054 trace_savevm_section_start(se->idstr, se->section_id); 1055 1056 save_section_header(f, se, QEMU_VM_SECTION_END); 1057 1058 ret = se->ops->save_live_complete_precopy(f, se->opaque); 1059 trace_savevm_section_end(se->idstr, se->section_id, ret); 1060 save_section_footer(f, se); 1061 if (ret < 0) { 1062 qemu_file_set_error(f, ret); 1063 return; 1064 } 1065 } 1066 1067 if (iterable_only) { 1068 return; 1069 } 1070 1071 vmdesc = qjson_new(); 1072 json_prop_int(vmdesc, "page_size", TARGET_PAGE_SIZE); 1073 json_start_array(vmdesc, "devices"); 1074 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1075 1076 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1077 continue; 1078 } 1079 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1080 trace_savevm_section_skip(se->idstr, se->section_id); 1081 continue; 1082 } 1083 1084 trace_savevm_section_start(se->idstr, se->section_id); 1085 1086 json_start_object(vmdesc, NULL); 1087 json_prop_str(vmdesc, "name", se->idstr); 1088 json_prop_int(vmdesc, "instance_id", se->instance_id); 1089 1090 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1091 1092 vmstate_save(f, se, vmdesc); 1093 1094 json_end_object(vmdesc); 1095 trace_savevm_section_end(se->idstr, se->section_id, 0); 1096 save_section_footer(f, se); 1097 } 1098 1099 if (!in_postcopy) { 1100 /* Postcopy stream will still be going */ 1101 qemu_put_byte(f, QEMU_VM_EOF); 1102 } 1103 1104 json_end_array(vmdesc); 1105 qjson_finish(vmdesc); 1106 vmdesc_len = strlen(qjson_get_str(vmdesc)); 1107 1108 if (should_send_vmdesc()) { 1109 qemu_put_byte(f, QEMU_VM_VMDESCRIPTION); 1110 qemu_put_be32(f, vmdesc_len); 1111 qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len); 1112 } 1113 object_unref(OBJECT(vmdesc)); 1114 1115 qemu_fflush(f); 1116 } 1117 1118 /* Give an estimate of the amount left to be transferred, 1119 * the result is split into the amount for units that can and 1120 * for units that can't do postcopy. 1121 */ 1122 void qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size, 1123 uint64_t *res_non_postcopiable, 1124 uint64_t *res_postcopiable) 1125 { 1126 SaveStateEntry *se; 1127 1128 *res_non_postcopiable = 0; 1129 *res_postcopiable = 0; 1130 1131 1132 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1133 if (!se->ops || !se->ops->save_live_pending) { 1134 continue; 1135 } 1136 if (se->ops && se->ops->is_active) { 1137 if (!se->ops->is_active(se->opaque)) { 1138 continue; 1139 } 1140 } 1141 se->ops->save_live_pending(f, se->opaque, max_size, 1142 res_non_postcopiable, res_postcopiable); 1143 } 1144 } 1145 1146 void qemu_savevm_state_cleanup(void) 1147 { 1148 SaveStateEntry *se; 1149 1150 trace_savevm_state_cleanup(); 1151 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1152 if (se->ops && se->ops->cleanup) { 1153 se->ops->cleanup(se->opaque); 1154 } 1155 } 1156 } 1157 1158 static int qemu_savevm_state(QEMUFile *f, Error **errp) 1159 { 1160 int ret; 1161 MigrationParams params = { 1162 .blk = 0, 1163 .shared = 0 1164 }; 1165 MigrationState *ms = migrate_init(¶ms); 1166 ms->file = f; 1167 1168 if (qemu_savevm_state_blocked(errp)) { 1169 return -EINVAL; 1170 } 1171 1172 qemu_mutex_unlock_iothread(); 1173 qemu_savevm_state_header(f); 1174 qemu_savevm_state_begin(f, ¶ms); 1175 qemu_mutex_lock_iothread(); 1176 1177 while (qemu_file_get_error(f) == 0) { 1178 if (qemu_savevm_state_iterate(f, false) > 0) { 1179 break; 1180 } 1181 } 1182 1183 ret = qemu_file_get_error(f); 1184 if (ret == 0) { 1185 qemu_savevm_state_complete_precopy(f, false); 1186 ret = qemu_file_get_error(f); 1187 } 1188 qemu_savevm_state_cleanup(); 1189 if (ret != 0) { 1190 error_setg_errno(errp, -ret, "Error while writing VM state"); 1191 } 1192 return ret; 1193 } 1194 1195 static int qemu_save_device_state(QEMUFile *f) 1196 { 1197 SaveStateEntry *se; 1198 1199 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 1200 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 1201 1202 cpu_synchronize_all_states(); 1203 1204 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1205 if (se->is_ram) { 1206 continue; 1207 } 1208 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1209 continue; 1210 } 1211 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1212 continue; 1213 } 1214 1215 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1216 1217 vmstate_save(f, se, NULL); 1218 1219 save_section_footer(f, se); 1220 } 1221 1222 qemu_put_byte(f, QEMU_VM_EOF); 1223 1224 return qemu_file_get_error(f); 1225 } 1226 1227 static SaveStateEntry *find_se(const char *idstr, int instance_id) 1228 { 1229 SaveStateEntry *se; 1230 1231 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1232 if (!strcmp(se->idstr, idstr) && 1233 (instance_id == se->instance_id || 1234 instance_id == se->alias_id)) 1235 return se; 1236 /* Migrating from an older version? */ 1237 if (strstr(se->idstr, idstr) && se->compat) { 1238 if (!strcmp(se->compat->idstr, idstr) && 1239 (instance_id == se->compat->instance_id || 1240 instance_id == se->alias_id)) 1241 return se; 1242 } 1243 } 1244 return NULL; 1245 } 1246 1247 enum LoadVMExitCodes { 1248 /* Allow a command to quit all layers of nested loadvm loops */ 1249 LOADVM_QUIT = 1, 1250 }; 1251 1252 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis); 1253 1254 /* ------ incoming postcopy messages ------ */ 1255 /* 'advise' arrives before any transfers just to tell us that a postcopy 1256 * *might* happen - it might be skipped if precopy transferred everything 1257 * quickly. 1258 */ 1259 static int loadvm_postcopy_handle_advise(MigrationIncomingState *mis) 1260 { 1261 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1262 uint64_t remote_hps, remote_tps; 1263 1264 trace_loadvm_postcopy_handle_advise(); 1265 if (ps != POSTCOPY_INCOMING_NONE) { 1266 error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps); 1267 return -1; 1268 } 1269 1270 if (!postcopy_ram_supported_by_host()) { 1271 return -1; 1272 } 1273 1274 remote_hps = qemu_get_be64(mis->from_src_file); 1275 if (remote_hps != getpagesize()) { 1276 /* 1277 * Some combinations of mismatch are probably possible but it gets 1278 * a bit more complicated. In particular we need to place whole 1279 * host pages on the dest at once, and we need to ensure that we 1280 * handle dirtying to make sure we never end up sending part of 1281 * a hostpage on it's own. 1282 */ 1283 error_report("Postcopy needs matching host page sizes (s=%d d=%d)", 1284 (int)remote_hps, getpagesize()); 1285 return -1; 1286 } 1287 1288 remote_tps = qemu_get_be64(mis->from_src_file); 1289 if (remote_tps != (1ul << qemu_target_page_bits())) { 1290 /* 1291 * Again, some differences could be dealt with, but for now keep it 1292 * simple. 1293 */ 1294 error_report("Postcopy needs matching target page sizes (s=%d d=%d)", 1295 (int)remote_tps, 1 << qemu_target_page_bits()); 1296 return -1; 1297 } 1298 1299 if (ram_postcopy_incoming_init(mis)) { 1300 return -1; 1301 } 1302 1303 postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1304 1305 return 0; 1306 } 1307 1308 /* After postcopy we will be told to throw some pages away since they're 1309 * dirty and will have to be demand fetched. Must happen before CPU is 1310 * started. 1311 * There can be 0..many of these messages, each encoding multiple pages. 1312 */ 1313 static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState *mis, 1314 uint16_t len) 1315 { 1316 int tmp; 1317 char ramid[256]; 1318 PostcopyState ps = postcopy_state_get(); 1319 1320 trace_loadvm_postcopy_ram_handle_discard(); 1321 1322 switch (ps) { 1323 case POSTCOPY_INCOMING_ADVISE: 1324 /* 1st discard */ 1325 tmp = postcopy_ram_prepare_discard(mis); 1326 if (tmp) { 1327 return tmp; 1328 } 1329 break; 1330 1331 case POSTCOPY_INCOMING_DISCARD: 1332 /* Expected state */ 1333 break; 1334 1335 default: 1336 error_report("CMD_POSTCOPY_RAM_DISCARD in wrong postcopy state (%d)", 1337 ps); 1338 return -1; 1339 } 1340 /* We're expecting a 1341 * Version (0) 1342 * a RAM ID string (length byte, name, 0 term) 1343 * then at least 1 16 byte chunk 1344 */ 1345 if (len < (1 + 1 + 1 + 1 + 2 * 8)) { 1346 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1347 return -1; 1348 } 1349 1350 tmp = qemu_get_byte(mis->from_src_file); 1351 if (tmp != postcopy_ram_discard_version) { 1352 error_report("CMD_POSTCOPY_RAM_DISCARD invalid version (%d)", tmp); 1353 return -1; 1354 } 1355 1356 if (!qemu_get_counted_string(mis->from_src_file, ramid)) { 1357 error_report("CMD_POSTCOPY_RAM_DISCARD Failed to read RAMBlock ID"); 1358 return -1; 1359 } 1360 tmp = qemu_get_byte(mis->from_src_file); 1361 if (tmp != 0) { 1362 error_report("CMD_POSTCOPY_RAM_DISCARD missing nil (%d)", tmp); 1363 return -1; 1364 } 1365 1366 len -= 3 + strlen(ramid); 1367 if (len % 16) { 1368 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1369 return -1; 1370 } 1371 trace_loadvm_postcopy_ram_handle_discard_header(ramid, len); 1372 while (len) { 1373 uint64_t start_addr, block_length; 1374 start_addr = qemu_get_be64(mis->from_src_file); 1375 block_length = qemu_get_be64(mis->from_src_file); 1376 1377 len -= 16; 1378 int ret = ram_discard_range(mis, ramid, start_addr, 1379 block_length); 1380 if (ret) { 1381 return ret; 1382 } 1383 } 1384 trace_loadvm_postcopy_ram_handle_discard_end(); 1385 1386 return 0; 1387 } 1388 1389 /* 1390 * Triggered by a postcopy_listen command; this thread takes over reading 1391 * the input stream, leaving the main thread free to carry on loading the rest 1392 * of the device state (from RAM). 1393 * (TODO:This could do with being in a postcopy file - but there again it's 1394 * just another input loop, not that postcopy specific) 1395 */ 1396 static void *postcopy_ram_listen_thread(void *opaque) 1397 { 1398 QEMUFile *f = opaque; 1399 MigrationIncomingState *mis = migration_incoming_get_current(); 1400 int load_res; 1401 1402 qemu_sem_post(&mis->listen_thread_sem); 1403 trace_postcopy_ram_listen_thread_start(); 1404 1405 /* 1406 * Because we're a thread and not a coroutine we can't yield 1407 * in qemu_file, and thus we must be blocking now. 1408 */ 1409 qemu_file_set_blocking(f, true); 1410 load_res = qemu_loadvm_state_main(f, mis); 1411 /* And non-blocking again so we don't block in any cleanup */ 1412 qemu_file_set_blocking(f, false); 1413 1414 trace_postcopy_ram_listen_thread_exit(); 1415 if (load_res < 0) { 1416 error_report("%s: loadvm failed: %d", __func__, load_res); 1417 qemu_file_set_error(f, load_res); 1418 } else { 1419 /* 1420 * This looks good, but it's possible that the device loading in the 1421 * main thread hasn't finished yet, and so we might not be in 'RUN' 1422 * state yet; wait for the end of the main thread. 1423 */ 1424 qemu_event_wait(&mis->main_thread_load_event); 1425 } 1426 postcopy_ram_incoming_cleanup(mis); 1427 /* 1428 * If everything has worked fine, then the main thread has waited 1429 * for us to start, and we're the last use of the mis. 1430 * (If something broke then qemu will have to exit anyway since it's 1431 * got a bad migration state). 1432 */ 1433 migration_incoming_state_destroy(); 1434 1435 if (load_res < 0) { 1436 /* 1437 * If something went wrong then we have a bad state so exit; 1438 * depending how far we got it might be possible at this point 1439 * to leave the guest running and fire MCEs for pages that never 1440 * arrived as a desperate recovery step. 1441 */ 1442 exit(EXIT_FAILURE); 1443 } 1444 1445 return NULL; 1446 } 1447 1448 /* After this message we must be able to immediately receive postcopy data */ 1449 static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) 1450 { 1451 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING); 1452 trace_loadvm_postcopy_handle_listen(); 1453 if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) { 1454 error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps); 1455 return -1; 1456 } 1457 if (ps == POSTCOPY_INCOMING_ADVISE) { 1458 /* 1459 * A rare case, we entered listen without having to do any discards, 1460 * so do the setup that's normally done at the time of the 1st discard. 1461 */ 1462 postcopy_ram_prepare_discard(mis); 1463 } 1464 1465 /* 1466 * Sensitise RAM - can now generate requests for blocks that don't exist 1467 * However, at this point the CPU shouldn't be running, and the IO 1468 * shouldn't be doing anything yet so don't actually expect requests 1469 */ 1470 if (postcopy_ram_enable_notify(mis)) { 1471 return -1; 1472 } 1473 1474 if (mis->have_listen_thread) { 1475 error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread"); 1476 return -1; 1477 } 1478 1479 mis->have_listen_thread = true; 1480 /* Start up the listening thread and wait for it to signal ready */ 1481 qemu_sem_init(&mis->listen_thread_sem, 0); 1482 qemu_thread_create(&mis->listen_thread, "postcopy/listen", 1483 postcopy_ram_listen_thread, mis->from_src_file, 1484 QEMU_THREAD_JOINABLE); 1485 qemu_sem_wait(&mis->listen_thread_sem); 1486 qemu_sem_destroy(&mis->listen_thread_sem); 1487 1488 return 0; 1489 } 1490 1491 /* After all discards we can start running and asking for pages */ 1492 static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) 1493 { 1494 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_RUNNING); 1495 Error *local_err = NULL; 1496 1497 trace_loadvm_postcopy_handle_run(); 1498 if (ps != POSTCOPY_INCOMING_LISTENING) { 1499 error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps); 1500 return -1; 1501 } 1502 1503 /* TODO we should move all of this lot into postcopy_ram.c or a shared code 1504 * in migration.c 1505 */ 1506 cpu_synchronize_all_post_init(); 1507 1508 qemu_announce_self(); 1509 1510 /* Make sure all file formats flush their mutable metadata */ 1511 bdrv_invalidate_cache_all(&local_err); 1512 if (local_err) { 1513 error_report_err(local_err); 1514 return -1; 1515 } 1516 1517 trace_loadvm_postcopy_handle_run_cpu_sync(); 1518 cpu_synchronize_all_post_init(); 1519 1520 trace_loadvm_postcopy_handle_run_vmstart(); 1521 1522 if (autostart) { 1523 /* Hold onto your hats, starting the CPU */ 1524 vm_start(); 1525 } else { 1526 /* leave it paused and let management decide when to start the CPU */ 1527 runstate_set(RUN_STATE_PAUSED); 1528 } 1529 1530 /* We need to finish reading the stream from the package 1531 * and also stop reading anything more from the stream that loaded the 1532 * package (since it's now being read by the listener thread). 1533 * LOADVM_QUIT will quit all the layers of nested loadvm loops. 1534 */ 1535 return LOADVM_QUIT; 1536 } 1537 1538 /** 1539 * Immediately following this command is a blob of data containing an embedded 1540 * chunk of migration stream; read it and load it. 1541 * 1542 * @mis: Incoming state 1543 * @length: Length of packaged data to read 1544 * 1545 * Returns: Negative values on error 1546 * 1547 */ 1548 static int loadvm_handle_cmd_packaged(MigrationIncomingState *mis) 1549 { 1550 int ret; 1551 uint8_t *buffer; 1552 uint32_t length; 1553 QEMUSizedBuffer *qsb; 1554 1555 length = qemu_get_be32(mis->from_src_file); 1556 trace_loadvm_handle_cmd_packaged(length); 1557 1558 if (length > MAX_VM_CMD_PACKAGED_SIZE) { 1559 error_report("Unreasonably large packaged state: %u", length); 1560 return -1; 1561 } 1562 buffer = g_malloc0(length); 1563 ret = qemu_get_buffer(mis->from_src_file, buffer, (int)length); 1564 if (ret != length) { 1565 g_free(buffer); 1566 error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%d\n", 1567 ret, length); 1568 return (ret < 0) ? ret : -EAGAIN; 1569 } 1570 trace_loadvm_handle_cmd_packaged_received(ret); 1571 1572 /* Setup a dummy QEMUFile that actually reads from the buffer */ 1573 qsb = qsb_create(buffer, length); 1574 g_free(buffer); /* Because qsb_create copies */ 1575 if (!qsb) { 1576 error_report("Unable to create qsb"); 1577 } 1578 QEMUFile *packf = qemu_bufopen("r", qsb); 1579 1580 ret = qemu_loadvm_state_main(packf, mis); 1581 trace_loadvm_handle_cmd_packaged_main(ret); 1582 qemu_fclose(packf); 1583 qsb_free(qsb); 1584 1585 return ret; 1586 } 1587 1588 /* 1589 * Process an incoming 'QEMU_VM_COMMAND' 1590 * 0 just a normal return 1591 * LOADVM_QUIT All good, but exit the loop 1592 * <0 Error 1593 */ 1594 static int loadvm_process_command(QEMUFile *f) 1595 { 1596 MigrationIncomingState *mis = migration_incoming_get_current(); 1597 uint16_t cmd; 1598 uint16_t len; 1599 uint32_t tmp32; 1600 1601 cmd = qemu_get_be16(f); 1602 len = qemu_get_be16(f); 1603 1604 trace_loadvm_process_command(cmd, len); 1605 if (cmd >= MIG_CMD_MAX || cmd == MIG_CMD_INVALID) { 1606 error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd, len); 1607 return -EINVAL; 1608 } 1609 1610 if (mig_cmd_args[cmd].len != -1 && mig_cmd_args[cmd].len != len) { 1611 error_report("%s received with bad length - expecting %zu, got %d", 1612 mig_cmd_args[cmd].name, 1613 (size_t)mig_cmd_args[cmd].len, len); 1614 return -ERANGE; 1615 } 1616 1617 switch (cmd) { 1618 case MIG_CMD_OPEN_RETURN_PATH: 1619 if (mis->to_src_file) { 1620 error_report("CMD_OPEN_RETURN_PATH called when RP already open"); 1621 /* Not really a problem, so don't give up */ 1622 return 0; 1623 } 1624 mis->to_src_file = qemu_file_get_return_path(f); 1625 if (!mis->to_src_file) { 1626 error_report("CMD_OPEN_RETURN_PATH failed"); 1627 return -1; 1628 } 1629 break; 1630 1631 case MIG_CMD_PING: 1632 tmp32 = qemu_get_be32(f); 1633 trace_loadvm_process_command_ping(tmp32); 1634 if (!mis->to_src_file) { 1635 error_report("CMD_PING (0x%x) received with no return path", 1636 tmp32); 1637 return -1; 1638 } 1639 migrate_send_rp_pong(mis, tmp32); 1640 break; 1641 1642 case MIG_CMD_PACKAGED: 1643 return loadvm_handle_cmd_packaged(mis); 1644 1645 case MIG_CMD_POSTCOPY_ADVISE: 1646 return loadvm_postcopy_handle_advise(mis); 1647 1648 case MIG_CMD_POSTCOPY_LISTEN: 1649 return loadvm_postcopy_handle_listen(mis); 1650 1651 case MIG_CMD_POSTCOPY_RUN: 1652 return loadvm_postcopy_handle_run(mis); 1653 1654 case MIG_CMD_POSTCOPY_RAM_DISCARD: 1655 return loadvm_postcopy_ram_handle_discard(mis, len); 1656 } 1657 1658 return 0; 1659 } 1660 1661 struct LoadStateEntry { 1662 QLIST_ENTRY(LoadStateEntry) entry; 1663 SaveStateEntry *se; 1664 int section_id; 1665 int version_id; 1666 }; 1667 1668 /* 1669 * Read a footer off the wire and check that it matches the expected section 1670 * 1671 * Returns: true if the footer was good 1672 * false if there is a problem (and calls error_report to say why) 1673 */ 1674 static bool check_section_footer(QEMUFile *f, LoadStateEntry *le) 1675 { 1676 uint8_t read_mark; 1677 uint32_t read_section_id; 1678 1679 if (skip_section_footers) { 1680 /* No footer to check */ 1681 return true; 1682 } 1683 1684 read_mark = qemu_get_byte(f); 1685 1686 if (read_mark != QEMU_VM_SECTION_FOOTER) { 1687 error_report("Missing section footer for %s", le->se->idstr); 1688 return false; 1689 } 1690 1691 read_section_id = qemu_get_be32(f); 1692 if (read_section_id != le->section_id) { 1693 error_report("Mismatched section id in footer for %s -" 1694 " read 0x%x expected 0x%x", 1695 le->se->idstr, read_section_id, le->section_id); 1696 return false; 1697 } 1698 1699 /* All good */ 1700 return true; 1701 } 1702 1703 void loadvm_free_handlers(MigrationIncomingState *mis) 1704 { 1705 LoadStateEntry *le, *new_le; 1706 1707 QLIST_FOREACH_SAFE(le, &mis->loadvm_handlers, entry, new_le) { 1708 QLIST_REMOVE(le, entry); 1709 g_free(le); 1710 } 1711 } 1712 1713 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis) 1714 { 1715 uint8_t section_type; 1716 int ret; 1717 1718 while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) { 1719 uint32_t instance_id, version_id, section_id; 1720 SaveStateEntry *se; 1721 LoadStateEntry *le; 1722 char idstr[256]; 1723 1724 trace_qemu_loadvm_state_section(section_type); 1725 switch (section_type) { 1726 case QEMU_VM_SECTION_START: 1727 case QEMU_VM_SECTION_FULL: 1728 /* Read section start */ 1729 section_id = qemu_get_be32(f); 1730 if (!qemu_get_counted_string(f, idstr)) { 1731 error_report("Unable to read ID string for section %u", 1732 section_id); 1733 return -EINVAL; 1734 } 1735 instance_id = qemu_get_be32(f); 1736 version_id = qemu_get_be32(f); 1737 1738 trace_qemu_loadvm_state_section_startfull(section_id, idstr, 1739 instance_id, version_id); 1740 /* Find savevm section */ 1741 se = find_se(idstr, instance_id); 1742 if (se == NULL) { 1743 error_report("Unknown savevm section or instance '%s' %d", 1744 idstr, instance_id); 1745 return -EINVAL; 1746 } 1747 1748 /* Validate version */ 1749 if (version_id > se->version_id) { 1750 error_report("savevm: unsupported version %d for '%s' v%d", 1751 version_id, idstr, se->version_id); 1752 return -EINVAL; 1753 } 1754 1755 /* Add entry */ 1756 le = g_malloc0(sizeof(*le)); 1757 1758 le->se = se; 1759 le->section_id = section_id; 1760 le->version_id = version_id; 1761 QLIST_INSERT_HEAD(&mis->loadvm_handlers, le, entry); 1762 1763 ret = vmstate_load(f, le->se, le->version_id); 1764 if (ret < 0) { 1765 error_report("error while loading state for instance 0x%x of" 1766 " device '%s'", instance_id, idstr); 1767 return ret; 1768 } 1769 if (!check_section_footer(f, le)) { 1770 return -EINVAL; 1771 } 1772 break; 1773 case QEMU_VM_SECTION_PART: 1774 case QEMU_VM_SECTION_END: 1775 section_id = qemu_get_be32(f); 1776 1777 trace_qemu_loadvm_state_section_partend(section_id); 1778 QLIST_FOREACH(le, &mis->loadvm_handlers, entry) { 1779 if (le->section_id == section_id) { 1780 break; 1781 } 1782 } 1783 if (le == NULL) { 1784 error_report("Unknown savevm section %d", section_id); 1785 return -EINVAL; 1786 } 1787 1788 ret = vmstate_load(f, le->se, le->version_id); 1789 if (ret < 0) { 1790 error_report("error while loading state section id %d(%s)", 1791 section_id, le->se->idstr); 1792 return ret; 1793 } 1794 if (!check_section_footer(f, le)) { 1795 return -EINVAL; 1796 } 1797 break; 1798 case QEMU_VM_COMMAND: 1799 ret = loadvm_process_command(f); 1800 trace_qemu_loadvm_state_section_command(ret); 1801 if ((ret < 0) || (ret & LOADVM_QUIT)) { 1802 return ret; 1803 } 1804 break; 1805 default: 1806 error_report("Unknown savevm section type %d", section_type); 1807 return -EINVAL; 1808 } 1809 } 1810 1811 return 0; 1812 } 1813 1814 int qemu_loadvm_state(QEMUFile *f) 1815 { 1816 MigrationIncomingState *mis = migration_incoming_get_current(); 1817 Error *local_err = NULL; 1818 unsigned int v; 1819 int ret; 1820 1821 if (qemu_savevm_state_blocked(&local_err)) { 1822 error_report_err(local_err); 1823 return -EINVAL; 1824 } 1825 1826 v = qemu_get_be32(f); 1827 if (v != QEMU_VM_FILE_MAGIC) { 1828 error_report("Not a migration stream"); 1829 return -EINVAL; 1830 } 1831 1832 v = qemu_get_be32(f); 1833 if (v == QEMU_VM_FILE_VERSION_COMPAT) { 1834 error_report("SaveVM v2 format is obsolete and don't work anymore"); 1835 return -ENOTSUP; 1836 } 1837 if (v != QEMU_VM_FILE_VERSION) { 1838 error_report("Unsupported migration stream version"); 1839 return -ENOTSUP; 1840 } 1841 1842 if (!savevm_state.skip_configuration) { 1843 if (qemu_get_byte(f) != QEMU_VM_CONFIGURATION) { 1844 error_report("Configuration section missing"); 1845 return -EINVAL; 1846 } 1847 ret = vmstate_load_state(f, &vmstate_configuration, &savevm_state, 0); 1848 1849 if (ret) { 1850 return ret; 1851 } 1852 } 1853 1854 ret = qemu_loadvm_state_main(f, mis); 1855 qemu_event_set(&mis->main_thread_load_event); 1856 1857 trace_qemu_loadvm_state_post_main(ret); 1858 1859 if (mis->have_listen_thread) { 1860 /* Listen thread still going, can't clean up yet */ 1861 return ret; 1862 } 1863 1864 if (ret == 0) { 1865 ret = qemu_file_get_error(f); 1866 } 1867 1868 /* 1869 * Try to read in the VMDESC section as well, so that dumping tools that 1870 * intercept our migration stream have the chance to see it. 1871 */ 1872 1873 /* We've got to be careful; if we don't read the data and just shut the fd 1874 * then the sender can error if we close while it's still sending. 1875 * We also mustn't read data that isn't there; some transports (RDMA) 1876 * will stall waiting for that data when the source has already closed. 1877 */ 1878 if (ret == 0 && should_send_vmdesc()) { 1879 uint8_t *buf; 1880 uint32_t size; 1881 uint8_t section_type = qemu_get_byte(f); 1882 1883 if (section_type != QEMU_VM_VMDESCRIPTION) { 1884 error_report("Expected vmdescription section, but got %d", 1885 section_type); 1886 /* 1887 * It doesn't seem worth failing at this point since 1888 * we apparently have an otherwise valid VM state 1889 */ 1890 } else { 1891 buf = g_malloc(0x1000); 1892 size = qemu_get_be32(f); 1893 1894 while (size > 0) { 1895 uint32_t read_chunk = MIN(size, 0x1000); 1896 qemu_get_buffer(f, buf, read_chunk); 1897 size -= read_chunk; 1898 } 1899 g_free(buf); 1900 } 1901 } 1902 1903 cpu_synchronize_all_post_init(); 1904 1905 return ret; 1906 } 1907 1908 static BlockDriverState *find_vmstate_bs(void) 1909 { 1910 BlockDriverState *bs = NULL; 1911 while ((bs = bdrv_next(bs))) { 1912 if (bdrv_can_snapshot(bs)) { 1913 return bs; 1914 } 1915 } 1916 return NULL; 1917 } 1918 1919 /* 1920 * Deletes snapshots of a given name in all opened images. 1921 */ 1922 static int del_existing_snapshots(Monitor *mon, const char *name) 1923 { 1924 BlockDriverState *bs; 1925 QEMUSnapshotInfo sn1, *snapshot = &sn1; 1926 Error *err = NULL; 1927 1928 bs = NULL; 1929 while ((bs = bdrv_next(bs))) { 1930 if (bdrv_can_snapshot(bs) && 1931 bdrv_snapshot_find(bs, snapshot, name) >= 0) { 1932 bdrv_snapshot_delete_by_id_or_name(bs, name, &err); 1933 if (err) { 1934 monitor_printf(mon, 1935 "Error while deleting snapshot on device '%s':" 1936 " %s\n", 1937 bdrv_get_device_name(bs), 1938 error_get_pretty(err)); 1939 error_free(err); 1940 return -1; 1941 } 1942 } 1943 } 1944 1945 return 0; 1946 } 1947 1948 void hmp_savevm(Monitor *mon, const QDict *qdict) 1949 { 1950 BlockDriverState *bs, *bs1; 1951 QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1; 1952 int ret; 1953 QEMUFile *f; 1954 int saved_vm_running; 1955 uint64_t vm_state_size; 1956 qemu_timeval tv; 1957 struct tm tm; 1958 const char *name = qdict_get_try_str(qdict, "name"); 1959 Error *local_err = NULL; 1960 1961 /* Verify if there is a device that doesn't support snapshots and is writable */ 1962 bs = NULL; 1963 while ((bs = bdrv_next(bs))) { 1964 1965 if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) { 1966 continue; 1967 } 1968 1969 if (!bdrv_can_snapshot(bs)) { 1970 monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n", 1971 bdrv_get_device_name(bs)); 1972 return; 1973 } 1974 } 1975 1976 bs = find_vmstate_bs(); 1977 if (!bs) { 1978 monitor_printf(mon, "No block device can accept snapshots\n"); 1979 return; 1980 } 1981 1982 saved_vm_running = runstate_is_running(); 1983 1984 ret = global_state_store(); 1985 if (ret) { 1986 monitor_printf(mon, "Error saving global state\n"); 1987 return; 1988 } 1989 vm_stop(RUN_STATE_SAVE_VM); 1990 1991 memset(sn, 0, sizeof(*sn)); 1992 1993 /* fill auxiliary fields */ 1994 qemu_gettimeofday(&tv); 1995 sn->date_sec = tv.tv_sec; 1996 sn->date_nsec = tv.tv_usec * 1000; 1997 sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 1998 1999 if (name) { 2000 ret = bdrv_snapshot_find(bs, old_sn, name); 2001 if (ret >= 0) { 2002 pstrcpy(sn->name, sizeof(sn->name), old_sn->name); 2003 pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str); 2004 } else { 2005 pstrcpy(sn->name, sizeof(sn->name), name); 2006 } 2007 } else { 2008 /* cast below needed for OpenBSD where tv_sec is still 'long' */ 2009 localtime_r((const time_t *)&tv.tv_sec, &tm); 2010 strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm); 2011 } 2012 2013 /* Delete old snapshots of the same name */ 2014 if (name && del_existing_snapshots(mon, name) < 0) { 2015 goto the_end; 2016 } 2017 2018 /* save the VM state */ 2019 f = qemu_fopen_bdrv(bs, 1); 2020 if (!f) { 2021 monitor_printf(mon, "Could not open VM state file\n"); 2022 goto the_end; 2023 } 2024 ret = qemu_savevm_state(f, &local_err); 2025 vm_state_size = qemu_ftell(f); 2026 qemu_fclose(f); 2027 if (ret < 0) { 2028 monitor_printf(mon, "%s\n", error_get_pretty(local_err)); 2029 error_free(local_err); 2030 goto the_end; 2031 } 2032 2033 /* create the snapshots */ 2034 2035 bs1 = NULL; 2036 while ((bs1 = bdrv_next(bs1))) { 2037 if (bdrv_can_snapshot(bs1)) { 2038 /* Write VM state size only to the image that contains the state */ 2039 sn->vm_state_size = (bs == bs1 ? vm_state_size : 0); 2040 ret = bdrv_snapshot_create(bs1, sn); 2041 if (ret < 0) { 2042 monitor_printf(mon, "Error while creating snapshot on '%s'\n", 2043 bdrv_get_device_name(bs1)); 2044 } 2045 } 2046 } 2047 2048 the_end: 2049 if (saved_vm_running) { 2050 vm_start(); 2051 } 2052 } 2053 2054 void qmp_xen_save_devices_state(const char *filename, Error **errp) 2055 { 2056 QEMUFile *f; 2057 int saved_vm_running; 2058 int ret; 2059 2060 saved_vm_running = runstate_is_running(); 2061 vm_stop(RUN_STATE_SAVE_VM); 2062 global_state_store_running(); 2063 2064 f = qemu_fopen(filename, "wb"); 2065 if (!f) { 2066 error_setg_file_open(errp, errno, filename); 2067 goto the_end; 2068 } 2069 ret = qemu_save_device_state(f); 2070 qemu_fclose(f); 2071 if (ret < 0) { 2072 error_setg(errp, QERR_IO_ERROR); 2073 } 2074 2075 the_end: 2076 if (saved_vm_running) { 2077 vm_start(); 2078 } 2079 } 2080 2081 int load_vmstate(const char *name) 2082 { 2083 BlockDriverState *bs, *bs_vm_state; 2084 QEMUSnapshotInfo sn; 2085 QEMUFile *f; 2086 int ret; 2087 2088 bs_vm_state = find_vmstate_bs(); 2089 if (!bs_vm_state) { 2090 error_report("No block device supports snapshots"); 2091 return -ENOTSUP; 2092 } 2093 2094 /* Don't even try to load empty VM states */ 2095 ret = bdrv_snapshot_find(bs_vm_state, &sn, name); 2096 if (ret < 0) { 2097 return ret; 2098 } else if (sn.vm_state_size == 0) { 2099 error_report("This is a disk-only snapshot. Revert to it offline " 2100 "using qemu-img."); 2101 return -EINVAL; 2102 } 2103 2104 /* Verify if there is any device that doesn't support snapshots and is 2105 writable and check if the requested snapshot is available too. */ 2106 bs = NULL; 2107 while ((bs = bdrv_next(bs))) { 2108 2109 if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) { 2110 continue; 2111 } 2112 2113 if (!bdrv_can_snapshot(bs)) { 2114 error_report("Device '%s' is writable but does not support snapshots.", 2115 bdrv_get_device_name(bs)); 2116 return -ENOTSUP; 2117 } 2118 2119 ret = bdrv_snapshot_find(bs, &sn, name); 2120 if (ret < 0) { 2121 error_report("Device '%s' does not have the requested snapshot '%s'", 2122 bdrv_get_device_name(bs), name); 2123 return ret; 2124 } 2125 } 2126 2127 /* Flush all IO requests so they don't interfere with the new state. */ 2128 bdrv_drain_all(); 2129 2130 bs = NULL; 2131 while ((bs = bdrv_next(bs))) { 2132 if (bdrv_can_snapshot(bs)) { 2133 ret = bdrv_snapshot_goto(bs, name); 2134 if (ret < 0) { 2135 error_report("Error %d while activating snapshot '%s' on '%s'", 2136 ret, name, bdrv_get_device_name(bs)); 2137 return ret; 2138 } 2139 } 2140 } 2141 2142 /* restore the VM state */ 2143 f = qemu_fopen_bdrv(bs_vm_state, 0); 2144 if (!f) { 2145 error_report("Could not open VM state file"); 2146 return -EINVAL; 2147 } 2148 2149 qemu_system_reset(VMRESET_SILENT); 2150 migration_incoming_state_new(f); 2151 ret = qemu_loadvm_state(f); 2152 2153 qemu_fclose(f); 2154 migration_incoming_state_destroy(); 2155 if (ret < 0) { 2156 error_report("Error %d while loading VM state", ret); 2157 return ret; 2158 } 2159 2160 return 0; 2161 } 2162 2163 void hmp_delvm(Monitor *mon, const QDict *qdict) 2164 { 2165 BlockDriverState *bs; 2166 Error *err; 2167 const char *name = qdict_get_str(qdict, "name"); 2168 2169 if (!find_vmstate_bs()) { 2170 monitor_printf(mon, "No block device supports snapshots\n"); 2171 return; 2172 } 2173 2174 bs = NULL; 2175 while ((bs = bdrv_next(bs))) { 2176 if (bdrv_can_snapshot(bs)) { 2177 err = NULL; 2178 bdrv_snapshot_delete_by_id_or_name(bs, name, &err); 2179 if (err) { 2180 monitor_printf(mon, 2181 "Error while deleting snapshot on device '%s':" 2182 " %s\n", 2183 bdrv_get_device_name(bs), 2184 error_get_pretty(err)); 2185 error_free(err); 2186 } 2187 } 2188 } 2189 } 2190 2191 void hmp_info_snapshots(Monitor *mon, const QDict *qdict) 2192 { 2193 BlockDriverState *bs, *bs1; 2194 QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s; 2195 int nb_sns, i, ret, available; 2196 int total; 2197 int *available_snapshots; 2198 2199 bs = find_vmstate_bs(); 2200 if (!bs) { 2201 monitor_printf(mon, "No available block device supports snapshots\n"); 2202 return; 2203 } 2204 2205 nb_sns = bdrv_snapshot_list(bs, &sn_tab); 2206 if (nb_sns < 0) { 2207 monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns); 2208 return; 2209 } 2210 2211 if (nb_sns == 0) { 2212 monitor_printf(mon, "There is no snapshot available.\n"); 2213 return; 2214 } 2215 2216 available_snapshots = g_new0(int, nb_sns); 2217 total = 0; 2218 for (i = 0; i < nb_sns; i++) { 2219 sn = &sn_tab[i]; 2220 available = 1; 2221 bs1 = NULL; 2222 2223 while ((bs1 = bdrv_next(bs1))) { 2224 if (bdrv_can_snapshot(bs1) && bs1 != bs) { 2225 ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str); 2226 if (ret < 0) { 2227 available = 0; 2228 break; 2229 } 2230 } 2231 } 2232 2233 if (available) { 2234 available_snapshots[total] = i; 2235 total++; 2236 } 2237 } 2238 2239 if (total > 0) { 2240 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL); 2241 monitor_printf(mon, "\n"); 2242 for (i = 0; i < total; i++) { 2243 sn = &sn_tab[available_snapshots[i]]; 2244 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn); 2245 monitor_printf(mon, "\n"); 2246 } 2247 } else { 2248 monitor_printf(mon, "There is no suitable snapshot available\n"); 2249 } 2250 2251 g_free(sn_tab); 2252 g_free(available_snapshots); 2253 2254 } 2255 2256 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev) 2257 { 2258 qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK, 2259 memory_region_name(mr), dev); 2260 } 2261 2262 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev) 2263 { 2264 qemu_ram_unset_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK); 2265 } 2266 2267 void vmstate_register_ram_global(MemoryRegion *mr) 2268 { 2269 vmstate_register_ram(mr, NULL); 2270 } 2271