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 "qemu/osdep.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 (int) state->len, 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 static bool enforce_config_section(void) 882 { 883 MachineState *machine = MACHINE(qdev_get_machine()); 884 return machine->enforce_config_section; 885 } 886 887 void qemu_savevm_state_header(QEMUFile *f) 888 { 889 trace_savevm_state_header(); 890 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 891 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 892 893 if (!savevm_state.skip_configuration || enforce_config_section()) { 894 qemu_put_byte(f, QEMU_VM_CONFIGURATION); 895 vmstate_save_state(f, &vmstate_configuration, &savevm_state, 0); 896 } 897 898 } 899 900 void qemu_savevm_state_begin(QEMUFile *f, 901 const MigrationParams *params) 902 { 903 SaveStateEntry *se; 904 int ret; 905 906 trace_savevm_state_begin(); 907 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 908 if (!se->ops || !se->ops->set_params) { 909 continue; 910 } 911 se->ops->set_params(params, se->opaque); 912 } 913 914 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 915 if (!se->ops || !se->ops->save_live_setup) { 916 continue; 917 } 918 if (se->ops && se->ops->is_active) { 919 if (!se->ops->is_active(se->opaque)) { 920 continue; 921 } 922 } 923 save_section_header(f, se, QEMU_VM_SECTION_START); 924 925 ret = se->ops->save_live_setup(f, se->opaque); 926 save_section_footer(f, se); 927 if (ret < 0) { 928 qemu_file_set_error(f, ret); 929 break; 930 } 931 } 932 } 933 934 /* 935 * this function has three return values: 936 * negative: there was one error, and we have -errno. 937 * 0 : We haven't finished, caller have to go again 938 * 1 : We have finished, we can go to complete phase 939 */ 940 int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy) 941 { 942 SaveStateEntry *se; 943 int ret = 1; 944 945 trace_savevm_state_iterate(); 946 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 947 if (!se->ops || !se->ops->save_live_iterate) { 948 continue; 949 } 950 if (se->ops && se->ops->is_active) { 951 if (!se->ops->is_active(se->opaque)) { 952 continue; 953 } 954 } 955 /* 956 * In the postcopy phase, any device that doesn't know how to 957 * do postcopy should have saved it's state in the _complete 958 * call that's already run, it might get confused if we call 959 * iterate afterwards. 960 */ 961 if (postcopy && !se->ops->save_live_complete_postcopy) { 962 continue; 963 } 964 if (qemu_file_rate_limit(f)) { 965 return 0; 966 } 967 trace_savevm_section_start(se->idstr, se->section_id); 968 969 save_section_header(f, se, QEMU_VM_SECTION_PART); 970 971 ret = se->ops->save_live_iterate(f, se->opaque); 972 trace_savevm_section_end(se->idstr, se->section_id, ret); 973 save_section_footer(f, se); 974 975 if (ret < 0) { 976 qemu_file_set_error(f, ret); 977 } 978 if (ret <= 0) { 979 /* Do not proceed to the next vmstate before this one reported 980 completion of the current stage. This serializes the migration 981 and reduces the probability that a faster changing state is 982 synchronized over and over again. */ 983 break; 984 } 985 } 986 return ret; 987 } 988 989 static bool should_send_vmdesc(void) 990 { 991 MachineState *machine = MACHINE(qdev_get_machine()); 992 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 993 return !machine->suppress_vmdesc && !in_postcopy; 994 } 995 996 /* 997 * Calls the save_live_complete_postcopy methods 998 * causing the last few pages to be sent immediately and doing any associated 999 * cleanup. 1000 * Note postcopy also calls qemu_savevm_state_complete_precopy to complete 1001 * all the other devices, but that happens at the point we switch to postcopy. 1002 */ 1003 void qemu_savevm_state_complete_postcopy(QEMUFile *f) 1004 { 1005 SaveStateEntry *se; 1006 int ret; 1007 1008 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1009 if (!se->ops || !se->ops->save_live_complete_postcopy) { 1010 continue; 1011 } 1012 if (se->ops && se->ops->is_active) { 1013 if (!se->ops->is_active(se->opaque)) { 1014 continue; 1015 } 1016 } 1017 trace_savevm_section_start(se->idstr, se->section_id); 1018 /* Section type */ 1019 qemu_put_byte(f, QEMU_VM_SECTION_END); 1020 qemu_put_be32(f, se->section_id); 1021 1022 ret = se->ops->save_live_complete_postcopy(f, se->opaque); 1023 trace_savevm_section_end(se->idstr, se->section_id, ret); 1024 save_section_footer(f, se); 1025 if (ret < 0) { 1026 qemu_file_set_error(f, ret); 1027 return; 1028 } 1029 } 1030 1031 qemu_put_byte(f, QEMU_VM_EOF); 1032 qemu_fflush(f); 1033 } 1034 1035 void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) 1036 { 1037 QJSON *vmdesc; 1038 int vmdesc_len; 1039 SaveStateEntry *se; 1040 int ret; 1041 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 1042 1043 trace_savevm_state_complete_precopy(); 1044 1045 cpu_synchronize_all_states(); 1046 1047 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1048 if (!se->ops || 1049 (in_postcopy && se->ops->save_live_complete_postcopy) || 1050 (in_postcopy && !iterable_only) || 1051 !se->ops->save_live_complete_precopy) { 1052 continue; 1053 } 1054 1055 if (se->ops && se->ops->is_active) { 1056 if (!se->ops->is_active(se->opaque)) { 1057 continue; 1058 } 1059 } 1060 trace_savevm_section_start(se->idstr, se->section_id); 1061 1062 save_section_header(f, se, QEMU_VM_SECTION_END); 1063 1064 ret = se->ops->save_live_complete_precopy(f, se->opaque); 1065 trace_savevm_section_end(se->idstr, se->section_id, ret); 1066 save_section_footer(f, se); 1067 if (ret < 0) { 1068 qemu_file_set_error(f, ret); 1069 return; 1070 } 1071 } 1072 1073 if (iterable_only) { 1074 return; 1075 } 1076 1077 vmdesc = qjson_new(); 1078 json_prop_int(vmdesc, "page_size", TARGET_PAGE_SIZE); 1079 json_start_array(vmdesc, "devices"); 1080 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1081 1082 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1083 continue; 1084 } 1085 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1086 trace_savevm_section_skip(se->idstr, se->section_id); 1087 continue; 1088 } 1089 1090 trace_savevm_section_start(se->idstr, se->section_id); 1091 1092 json_start_object(vmdesc, NULL); 1093 json_prop_str(vmdesc, "name", se->idstr); 1094 json_prop_int(vmdesc, "instance_id", se->instance_id); 1095 1096 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1097 vmstate_save(f, se, vmdesc); 1098 trace_savevm_section_end(se->idstr, se->section_id, 0); 1099 save_section_footer(f, se); 1100 1101 json_end_object(vmdesc); 1102 } 1103 1104 if (!in_postcopy) { 1105 /* Postcopy stream will still be going */ 1106 qemu_put_byte(f, QEMU_VM_EOF); 1107 } 1108 1109 json_end_array(vmdesc); 1110 qjson_finish(vmdesc); 1111 vmdesc_len = strlen(qjson_get_str(vmdesc)); 1112 1113 if (should_send_vmdesc()) { 1114 qemu_put_byte(f, QEMU_VM_VMDESCRIPTION); 1115 qemu_put_be32(f, vmdesc_len); 1116 qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len); 1117 } 1118 object_unref(OBJECT(vmdesc)); 1119 1120 qemu_fflush(f); 1121 } 1122 1123 /* Give an estimate of the amount left to be transferred, 1124 * the result is split into the amount for units that can and 1125 * for units that can't do postcopy. 1126 */ 1127 void qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size, 1128 uint64_t *res_non_postcopiable, 1129 uint64_t *res_postcopiable) 1130 { 1131 SaveStateEntry *se; 1132 1133 *res_non_postcopiable = 0; 1134 *res_postcopiable = 0; 1135 1136 1137 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1138 if (!se->ops || !se->ops->save_live_pending) { 1139 continue; 1140 } 1141 if (se->ops && se->ops->is_active) { 1142 if (!se->ops->is_active(se->opaque)) { 1143 continue; 1144 } 1145 } 1146 se->ops->save_live_pending(f, se->opaque, max_size, 1147 res_non_postcopiable, res_postcopiable); 1148 } 1149 } 1150 1151 void qemu_savevm_state_cleanup(void) 1152 { 1153 SaveStateEntry *se; 1154 1155 trace_savevm_state_cleanup(); 1156 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1157 if (se->ops && se->ops->cleanup) { 1158 se->ops->cleanup(se->opaque); 1159 } 1160 } 1161 } 1162 1163 static int qemu_savevm_state(QEMUFile *f, Error **errp) 1164 { 1165 int ret; 1166 MigrationParams params = { 1167 .blk = 0, 1168 .shared = 0 1169 }; 1170 MigrationState *ms = migrate_init(¶ms); 1171 ms->to_dst_file = f; 1172 1173 if (qemu_savevm_state_blocked(errp)) { 1174 return -EINVAL; 1175 } 1176 1177 qemu_mutex_unlock_iothread(); 1178 qemu_savevm_state_header(f); 1179 qemu_savevm_state_begin(f, ¶ms); 1180 qemu_mutex_lock_iothread(); 1181 1182 while (qemu_file_get_error(f) == 0) { 1183 if (qemu_savevm_state_iterate(f, false) > 0) { 1184 break; 1185 } 1186 } 1187 1188 ret = qemu_file_get_error(f); 1189 if (ret == 0) { 1190 qemu_savevm_state_complete_precopy(f, false); 1191 ret = qemu_file_get_error(f); 1192 } 1193 qemu_savevm_state_cleanup(); 1194 if (ret != 0) { 1195 error_setg_errno(errp, -ret, "Error while writing VM state"); 1196 } 1197 return ret; 1198 } 1199 1200 static int qemu_save_device_state(QEMUFile *f) 1201 { 1202 SaveStateEntry *se; 1203 1204 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 1205 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 1206 1207 cpu_synchronize_all_states(); 1208 1209 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1210 if (se->is_ram) { 1211 continue; 1212 } 1213 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1214 continue; 1215 } 1216 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1217 continue; 1218 } 1219 1220 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1221 1222 vmstate_save(f, se, NULL); 1223 1224 save_section_footer(f, se); 1225 } 1226 1227 qemu_put_byte(f, QEMU_VM_EOF); 1228 1229 return qemu_file_get_error(f); 1230 } 1231 1232 static SaveStateEntry *find_se(const char *idstr, int instance_id) 1233 { 1234 SaveStateEntry *se; 1235 1236 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1237 if (!strcmp(se->idstr, idstr) && 1238 (instance_id == se->instance_id || 1239 instance_id == se->alias_id)) 1240 return se; 1241 /* Migrating from an older version? */ 1242 if (strstr(se->idstr, idstr) && se->compat) { 1243 if (!strcmp(se->compat->idstr, idstr) && 1244 (instance_id == se->compat->instance_id || 1245 instance_id == se->alias_id)) 1246 return se; 1247 } 1248 } 1249 return NULL; 1250 } 1251 1252 enum LoadVMExitCodes { 1253 /* Allow a command to quit all layers of nested loadvm loops */ 1254 LOADVM_QUIT = 1, 1255 }; 1256 1257 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis); 1258 1259 /* ------ incoming postcopy messages ------ */ 1260 /* 'advise' arrives before any transfers just to tell us that a postcopy 1261 * *might* happen - it might be skipped if precopy transferred everything 1262 * quickly. 1263 */ 1264 static int loadvm_postcopy_handle_advise(MigrationIncomingState *mis) 1265 { 1266 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1267 uint64_t remote_hps, remote_tps; 1268 1269 trace_loadvm_postcopy_handle_advise(); 1270 if (ps != POSTCOPY_INCOMING_NONE) { 1271 error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps); 1272 return -1; 1273 } 1274 1275 if (!postcopy_ram_supported_by_host()) { 1276 return -1; 1277 } 1278 1279 remote_hps = qemu_get_be64(mis->from_src_file); 1280 if (remote_hps != getpagesize()) { 1281 /* 1282 * Some combinations of mismatch are probably possible but it gets 1283 * a bit more complicated. In particular we need to place whole 1284 * host pages on the dest at once, and we need to ensure that we 1285 * handle dirtying to make sure we never end up sending part of 1286 * a hostpage on it's own. 1287 */ 1288 error_report("Postcopy needs matching host page sizes (s=%d d=%d)", 1289 (int)remote_hps, getpagesize()); 1290 return -1; 1291 } 1292 1293 remote_tps = qemu_get_be64(mis->from_src_file); 1294 if (remote_tps != (1ul << qemu_target_page_bits())) { 1295 /* 1296 * Again, some differences could be dealt with, but for now keep it 1297 * simple. 1298 */ 1299 error_report("Postcopy needs matching target page sizes (s=%d d=%d)", 1300 (int)remote_tps, 1 << qemu_target_page_bits()); 1301 return -1; 1302 } 1303 1304 if (ram_postcopy_incoming_init(mis)) { 1305 return -1; 1306 } 1307 1308 postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1309 1310 return 0; 1311 } 1312 1313 /* After postcopy we will be told to throw some pages away since they're 1314 * dirty and will have to be demand fetched. Must happen before CPU is 1315 * started. 1316 * There can be 0..many of these messages, each encoding multiple pages. 1317 */ 1318 static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState *mis, 1319 uint16_t len) 1320 { 1321 int tmp; 1322 char ramid[256]; 1323 PostcopyState ps = postcopy_state_get(); 1324 1325 trace_loadvm_postcopy_ram_handle_discard(); 1326 1327 switch (ps) { 1328 case POSTCOPY_INCOMING_ADVISE: 1329 /* 1st discard */ 1330 tmp = postcopy_ram_prepare_discard(mis); 1331 if (tmp) { 1332 return tmp; 1333 } 1334 break; 1335 1336 case POSTCOPY_INCOMING_DISCARD: 1337 /* Expected state */ 1338 break; 1339 1340 default: 1341 error_report("CMD_POSTCOPY_RAM_DISCARD in wrong postcopy state (%d)", 1342 ps); 1343 return -1; 1344 } 1345 /* We're expecting a 1346 * Version (0) 1347 * a RAM ID string (length byte, name, 0 term) 1348 * then at least 1 16 byte chunk 1349 */ 1350 if (len < (1 + 1 + 1 + 1 + 2 * 8)) { 1351 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1352 return -1; 1353 } 1354 1355 tmp = qemu_get_byte(mis->from_src_file); 1356 if (tmp != postcopy_ram_discard_version) { 1357 error_report("CMD_POSTCOPY_RAM_DISCARD invalid version (%d)", tmp); 1358 return -1; 1359 } 1360 1361 if (!qemu_get_counted_string(mis->from_src_file, ramid)) { 1362 error_report("CMD_POSTCOPY_RAM_DISCARD Failed to read RAMBlock ID"); 1363 return -1; 1364 } 1365 tmp = qemu_get_byte(mis->from_src_file); 1366 if (tmp != 0) { 1367 error_report("CMD_POSTCOPY_RAM_DISCARD missing nil (%d)", tmp); 1368 return -1; 1369 } 1370 1371 len -= 3 + strlen(ramid); 1372 if (len % 16) { 1373 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1374 return -1; 1375 } 1376 trace_loadvm_postcopy_ram_handle_discard_header(ramid, len); 1377 while (len) { 1378 uint64_t start_addr, block_length; 1379 start_addr = qemu_get_be64(mis->from_src_file); 1380 block_length = qemu_get_be64(mis->from_src_file); 1381 1382 len -= 16; 1383 int ret = ram_discard_range(mis, ramid, start_addr, 1384 block_length); 1385 if (ret) { 1386 return ret; 1387 } 1388 } 1389 trace_loadvm_postcopy_ram_handle_discard_end(); 1390 1391 return 0; 1392 } 1393 1394 /* 1395 * Triggered by a postcopy_listen command; this thread takes over reading 1396 * the input stream, leaving the main thread free to carry on loading the rest 1397 * of the device state (from RAM). 1398 * (TODO:This could do with being in a postcopy file - but there again it's 1399 * just another input loop, not that postcopy specific) 1400 */ 1401 static void *postcopy_ram_listen_thread(void *opaque) 1402 { 1403 QEMUFile *f = opaque; 1404 MigrationIncomingState *mis = migration_incoming_get_current(); 1405 int load_res; 1406 1407 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, 1408 MIGRATION_STATUS_POSTCOPY_ACTIVE); 1409 qemu_sem_post(&mis->listen_thread_sem); 1410 trace_postcopy_ram_listen_thread_start(); 1411 1412 /* 1413 * Because we're a thread and not a coroutine we can't yield 1414 * in qemu_file, and thus we must be blocking now. 1415 */ 1416 qemu_file_set_blocking(f, true); 1417 load_res = qemu_loadvm_state_main(f, mis); 1418 /* And non-blocking again so we don't block in any cleanup */ 1419 qemu_file_set_blocking(f, false); 1420 1421 trace_postcopy_ram_listen_thread_exit(); 1422 if (load_res < 0) { 1423 error_report("%s: loadvm failed: %d", __func__, load_res); 1424 qemu_file_set_error(f, load_res); 1425 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1426 MIGRATION_STATUS_FAILED); 1427 } else { 1428 /* 1429 * This looks good, but it's possible that the device loading in the 1430 * main thread hasn't finished yet, and so we might not be in 'RUN' 1431 * state yet; wait for the end of the main thread. 1432 */ 1433 qemu_event_wait(&mis->main_thread_load_event); 1434 } 1435 postcopy_ram_incoming_cleanup(mis); 1436 1437 if (load_res < 0) { 1438 /* 1439 * If something went wrong then we have a bad state so exit; 1440 * depending how far we got it might be possible at this point 1441 * to leave the guest running and fire MCEs for pages that never 1442 * arrived as a desperate recovery step. 1443 */ 1444 exit(EXIT_FAILURE); 1445 } 1446 1447 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1448 MIGRATION_STATUS_COMPLETED); 1449 /* 1450 * If everything has worked fine, then the main thread has waited 1451 * for us to start, and we're the last use of the mis. 1452 * (If something broke then qemu will have to exit anyway since it's 1453 * got a bad migration state). 1454 */ 1455 migration_incoming_state_destroy(); 1456 1457 1458 return NULL; 1459 } 1460 1461 /* After this message we must be able to immediately receive postcopy data */ 1462 static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) 1463 { 1464 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING); 1465 trace_loadvm_postcopy_handle_listen(); 1466 if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) { 1467 error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps); 1468 return -1; 1469 } 1470 if (ps == POSTCOPY_INCOMING_ADVISE) { 1471 /* 1472 * A rare case, we entered listen without having to do any discards, 1473 * so do the setup that's normally done at the time of the 1st discard. 1474 */ 1475 postcopy_ram_prepare_discard(mis); 1476 } 1477 1478 /* 1479 * Sensitise RAM - can now generate requests for blocks that don't exist 1480 * However, at this point the CPU shouldn't be running, and the IO 1481 * shouldn't be doing anything yet so don't actually expect requests 1482 */ 1483 if (postcopy_ram_enable_notify(mis)) { 1484 return -1; 1485 } 1486 1487 if (mis->have_listen_thread) { 1488 error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread"); 1489 return -1; 1490 } 1491 1492 mis->have_listen_thread = true; 1493 /* Start up the listening thread and wait for it to signal ready */ 1494 qemu_sem_init(&mis->listen_thread_sem, 0); 1495 qemu_thread_create(&mis->listen_thread, "postcopy/listen", 1496 postcopy_ram_listen_thread, mis->from_src_file, 1497 QEMU_THREAD_DETACHED); 1498 qemu_sem_wait(&mis->listen_thread_sem); 1499 qemu_sem_destroy(&mis->listen_thread_sem); 1500 1501 return 0; 1502 } 1503 1504 1505 typedef struct { 1506 QEMUBH *bh; 1507 } HandleRunBhData; 1508 1509 static void loadvm_postcopy_handle_run_bh(void *opaque) 1510 { 1511 Error *local_err = NULL; 1512 HandleRunBhData *data = opaque; 1513 1514 /* TODO we should move all of this lot into postcopy_ram.c or a shared code 1515 * in migration.c 1516 */ 1517 cpu_synchronize_all_post_init(); 1518 1519 qemu_announce_self(); 1520 1521 /* Make sure all file formats flush their mutable metadata */ 1522 bdrv_invalidate_cache_all(&local_err); 1523 if (local_err) { 1524 error_report_err(local_err); 1525 } 1526 1527 trace_loadvm_postcopy_handle_run_cpu_sync(); 1528 cpu_synchronize_all_post_init(); 1529 1530 trace_loadvm_postcopy_handle_run_vmstart(); 1531 1532 if (autostart) { 1533 /* Hold onto your hats, starting the CPU */ 1534 vm_start(); 1535 } else { 1536 /* leave it paused and let management decide when to start the CPU */ 1537 runstate_set(RUN_STATE_PAUSED); 1538 } 1539 1540 qemu_bh_delete(data->bh); 1541 g_free(data); 1542 } 1543 1544 /* After all discards we can start running and asking for pages */ 1545 static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) 1546 { 1547 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_RUNNING); 1548 HandleRunBhData *data; 1549 1550 trace_loadvm_postcopy_handle_run(); 1551 if (ps != POSTCOPY_INCOMING_LISTENING) { 1552 error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps); 1553 return -1; 1554 } 1555 1556 data = g_new(HandleRunBhData, 1); 1557 data->bh = qemu_bh_new(loadvm_postcopy_handle_run_bh, data); 1558 qemu_bh_schedule(data->bh); 1559 1560 /* We need to finish reading the stream from the package 1561 * and also stop reading anything more from the stream that loaded the 1562 * package (since it's now being read by the listener thread). 1563 * LOADVM_QUIT will quit all the layers of nested loadvm loops. 1564 */ 1565 return LOADVM_QUIT; 1566 } 1567 1568 /** 1569 * Immediately following this command is a blob of data containing an embedded 1570 * chunk of migration stream; read it and load it. 1571 * 1572 * @mis: Incoming state 1573 * @length: Length of packaged data to read 1574 * 1575 * Returns: Negative values on error 1576 * 1577 */ 1578 static int loadvm_handle_cmd_packaged(MigrationIncomingState *mis) 1579 { 1580 int ret; 1581 uint8_t *buffer; 1582 uint32_t length; 1583 QEMUSizedBuffer *qsb; 1584 1585 length = qemu_get_be32(mis->from_src_file); 1586 trace_loadvm_handle_cmd_packaged(length); 1587 1588 if (length > MAX_VM_CMD_PACKAGED_SIZE) { 1589 error_report("Unreasonably large packaged state: %u", length); 1590 return -1; 1591 } 1592 buffer = g_malloc0(length); 1593 ret = qemu_get_buffer(mis->from_src_file, buffer, (int)length); 1594 if (ret != length) { 1595 g_free(buffer); 1596 error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%d", 1597 ret, length); 1598 return (ret < 0) ? ret : -EAGAIN; 1599 } 1600 trace_loadvm_handle_cmd_packaged_received(ret); 1601 1602 /* Setup a dummy QEMUFile that actually reads from the buffer */ 1603 qsb = qsb_create(buffer, length); 1604 g_free(buffer); /* Because qsb_create copies */ 1605 if (!qsb) { 1606 error_report("Unable to create qsb"); 1607 } 1608 QEMUFile *packf = qemu_bufopen("r", qsb); 1609 1610 ret = qemu_loadvm_state_main(packf, mis); 1611 trace_loadvm_handle_cmd_packaged_main(ret); 1612 qemu_fclose(packf); 1613 qsb_free(qsb); 1614 1615 return ret; 1616 } 1617 1618 /* 1619 * Process an incoming 'QEMU_VM_COMMAND' 1620 * 0 just a normal return 1621 * LOADVM_QUIT All good, but exit the loop 1622 * <0 Error 1623 */ 1624 static int loadvm_process_command(QEMUFile *f) 1625 { 1626 MigrationIncomingState *mis = migration_incoming_get_current(); 1627 uint16_t cmd; 1628 uint16_t len; 1629 uint32_t tmp32; 1630 1631 cmd = qemu_get_be16(f); 1632 len = qemu_get_be16(f); 1633 1634 trace_loadvm_process_command(cmd, len); 1635 if (cmd >= MIG_CMD_MAX || cmd == MIG_CMD_INVALID) { 1636 error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd, len); 1637 return -EINVAL; 1638 } 1639 1640 if (mig_cmd_args[cmd].len != -1 && mig_cmd_args[cmd].len != len) { 1641 error_report("%s received with bad length - expecting %zu, got %d", 1642 mig_cmd_args[cmd].name, 1643 (size_t)mig_cmd_args[cmd].len, len); 1644 return -ERANGE; 1645 } 1646 1647 switch (cmd) { 1648 case MIG_CMD_OPEN_RETURN_PATH: 1649 if (mis->to_src_file) { 1650 error_report("CMD_OPEN_RETURN_PATH called when RP already open"); 1651 /* Not really a problem, so don't give up */ 1652 return 0; 1653 } 1654 mis->to_src_file = qemu_file_get_return_path(f); 1655 if (!mis->to_src_file) { 1656 error_report("CMD_OPEN_RETURN_PATH failed"); 1657 return -1; 1658 } 1659 break; 1660 1661 case MIG_CMD_PING: 1662 tmp32 = qemu_get_be32(f); 1663 trace_loadvm_process_command_ping(tmp32); 1664 if (!mis->to_src_file) { 1665 error_report("CMD_PING (0x%x) received with no return path", 1666 tmp32); 1667 return -1; 1668 } 1669 migrate_send_rp_pong(mis, tmp32); 1670 break; 1671 1672 case MIG_CMD_PACKAGED: 1673 return loadvm_handle_cmd_packaged(mis); 1674 1675 case MIG_CMD_POSTCOPY_ADVISE: 1676 return loadvm_postcopy_handle_advise(mis); 1677 1678 case MIG_CMD_POSTCOPY_LISTEN: 1679 return loadvm_postcopy_handle_listen(mis); 1680 1681 case MIG_CMD_POSTCOPY_RUN: 1682 return loadvm_postcopy_handle_run(mis); 1683 1684 case MIG_CMD_POSTCOPY_RAM_DISCARD: 1685 return loadvm_postcopy_ram_handle_discard(mis, len); 1686 } 1687 1688 return 0; 1689 } 1690 1691 struct LoadStateEntry { 1692 QLIST_ENTRY(LoadStateEntry) entry; 1693 SaveStateEntry *se; 1694 int section_id; 1695 int version_id; 1696 }; 1697 1698 /* 1699 * Read a footer off the wire and check that it matches the expected section 1700 * 1701 * Returns: true if the footer was good 1702 * false if there is a problem (and calls error_report to say why) 1703 */ 1704 static bool check_section_footer(QEMUFile *f, LoadStateEntry *le) 1705 { 1706 uint8_t read_mark; 1707 uint32_t read_section_id; 1708 1709 if (skip_section_footers) { 1710 /* No footer to check */ 1711 return true; 1712 } 1713 1714 read_mark = qemu_get_byte(f); 1715 1716 if (read_mark != QEMU_VM_SECTION_FOOTER) { 1717 error_report("Missing section footer for %s", le->se->idstr); 1718 return false; 1719 } 1720 1721 read_section_id = qemu_get_be32(f); 1722 if (read_section_id != le->section_id) { 1723 error_report("Mismatched section id in footer for %s -" 1724 " read 0x%x expected 0x%x", 1725 le->se->idstr, read_section_id, le->section_id); 1726 return false; 1727 } 1728 1729 /* All good */ 1730 return true; 1731 } 1732 1733 void loadvm_free_handlers(MigrationIncomingState *mis) 1734 { 1735 LoadStateEntry *le, *new_le; 1736 1737 QLIST_FOREACH_SAFE(le, &mis->loadvm_handlers, entry, new_le) { 1738 QLIST_REMOVE(le, entry); 1739 g_free(le); 1740 } 1741 } 1742 1743 static int 1744 qemu_loadvm_section_start_full(QEMUFile *f, MigrationIncomingState *mis) 1745 { 1746 uint32_t instance_id, version_id, section_id; 1747 SaveStateEntry *se; 1748 LoadStateEntry *le; 1749 char idstr[256]; 1750 int ret; 1751 1752 /* Read section start */ 1753 section_id = qemu_get_be32(f); 1754 if (!qemu_get_counted_string(f, idstr)) { 1755 error_report("Unable to read ID string for section %u", 1756 section_id); 1757 return -EINVAL; 1758 } 1759 instance_id = qemu_get_be32(f); 1760 version_id = qemu_get_be32(f); 1761 1762 trace_qemu_loadvm_state_section_startfull(section_id, idstr, 1763 instance_id, version_id); 1764 /* Find savevm section */ 1765 se = find_se(idstr, instance_id); 1766 if (se == NULL) { 1767 error_report("Unknown savevm section or instance '%s' %d", 1768 idstr, instance_id); 1769 return -EINVAL; 1770 } 1771 1772 /* Validate version */ 1773 if (version_id > se->version_id) { 1774 error_report("savevm: unsupported version %d for '%s' v%d", 1775 version_id, idstr, se->version_id); 1776 return -EINVAL; 1777 } 1778 1779 /* Add entry */ 1780 le = g_malloc0(sizeof(*le)); 1781 1782 le->se = se; 1783 le->section_id = section_id; 1784 le->version_id = version_id; 1785 QLIST_INSERT_HEAD(&mis->loadvm_handlers, le, entry); 1786 1787 ret = vmstate_load(f, le->se, le->version_id); 1788 if (ret < 0) { 1789 error_report("error while loading state for instance 0x%x of" 1790 " device '%s'", instance_id, idstr); 1791 return ret; 1792 } 1793 if (!check_section_footer(f, le)) { 1794 return -EINVAL; 1795 } 1796 1797 return 0; 1798 } 1799 1800 static int 1801 qemu_loadvm_section_part_end(QEMUFile *f, MigrationIncomingState *mis) 1802 { 1803 uint32_t section_id; 1804 LoadStateEntry *le; 1805 int ret; 1806 1807 section_id = qemu_get_be32(f); 1808 1809 trace_qemu_loadvm_state_section_partend(section_id); 1810 QLIST_FOREACH(le, &mis->loadvm_handlers, entry) { 1811 if (le->section_id == section_id) { 1812 break; 1813 } 1814 } 1815 if (le == NULL) { 1816 error_report("Unknown savevm section %d", section_id); 1817 return -EINVAL; 1818 } 1819 1820 ret = vmstate_load(f, le->se, le->version_id); 1821 if (ret < 0) { 1822 error_report("error while loading state section id %d(%s)", 1823 section_id, le->se->idstr); 1824 return ret; 1825 } 1826 if (!check_section_footer(f, le)) { 1827 return -EINVAL; 1828 } 1829 1830 return 0; 1831 } 1832 1833 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis) 1834 { 1835 uint8_t section_type; 1836 int ret; 1837 1838 while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) { 1839 1840 trace_qemu_loadvm_state_section(section_type); 1841 switch (section_type) { 1842 case QEMU_VM_SECTION_START: 1843 case QEMU_VM_SECTION_FULL: 1844 ret = qemu_loadvm_section_start_full(f, mis); 1845 if (ret < 0) { 1846 return ret; 1847 } 1848 break; 1849 case QEMU_VM_SECTION_PART: 1850 case QEMU_VM_SECTION_END: 1851 ret = qemu_loadvm_section_part_end(f, mis); 1852 if (ret < 0) { 1853 return ret; 1854 } 1855 break; 1856 case QEMU_VM_COMMAND: 1857 ret = loadvm_process_command(f); 1858 trace_qemu_loadvm_state_section_command(ret); 1859 if ((ret < 0) || (ret & LOADVM_QUIT)) { 1860 return ret; 1861 } 1862 break; 1863 default: 1864 error_report("Unknown savevm section type %d", section_type); 1865 return -EINVAL; 1866 } 1867 } 1868 1869 return 0; 1870 } 1871 1872 int qemu_loadvm_state(QEMUFile *f) 1873 { 1874 MigrationIncomingState *mis = migration_incoming_get_current(); 1875 Error *local_err = NULL; 1876 unsigned int v; 1877 int ret; 1878 1879 if (qemu_savevm_state_blocked(&local_err)) { 1880 error_report_err(local_err); 1881 return -EINVAL; 1882 } 1883 1884 v = qemu_get_be32(f); 1885 if (v != QEMU_VM_FILE_MAGIC) { 1886 error_report("Not a migration stream"); 1887 return -EINVAL; 1888 } 1889 1890 v = qemu_get_be32(f); 1891 if (v == QEMU_VM_FILE_VERSION_COMPAT) { 1892 error_report("SaveVM v2 format is obsolete and don't work anymore"); 1893 return -ENOTSUP; 1894 } 1895 if (v != QEMU_VM_FILE_VERSION) { 1896 error_report("Unsupported migration stream version"); 1897 return -ENOTSUP; 1898 } 1899 1900 if (!savevm_state.skip_configuration || enforce_config_section()) { 1901 if (qemu_get_byte(f) != QEMU_VM_CONFIGURATION) { 1902 error_report("Configuration section missing"); 1903 return -EINVAL; 1904 } 1905 ret = vmstate_load_state(f, &vmstate_configuration, &savevm_state, 0); 1906 1907 if (ret) { 1908 return ret; 1909 } 1910 } 1911 1912 ret = qemu_loadvm_state_main(f, mis); 1913 qemu_event_set(&mis->main_thread_load_event); 1914 1915 trace_qemu_loadvm_state_post_main(ret); 1916 1917 if (mis->have_listen_thread) { 1918 /* Listen thread still going, can't clean up yet */ 1919 return ret; 1920 } 1921 1922 if (ret == 0) { 1923 ret = qemu_file_get_error(f); 1924 } 1925 1926 /* 1927 * Try to read in the VMDESC section as well, so that dumping tools that 1928 * intercept our migration stream have the chance to see it. 1929 */ 1930 1931 /* We've got to be careful; if we don't read the data and just shut the fd 1932 * then the sender can error if we close while it's still sending. 1933 * We also mustn't read data that isn't there; some transports (RDMA) 1934 * will stall waiting for that data when the source has already closed. 1935 */ 1936 if (ret == 0 && should_send_vmdesc()) { 1937 uint8_t *buf; 1938 uint32_t size; 1939 uint8_t section_type = qemu_get_byte(f); 1940 1941 if (section_type != QEMU_VM_VMDESCRIPTION) { 1942 error_report("Expected vmdescription section, but got %d", 1943 section_type); 1944 /* 1945 * It doesn't seem worth failing at this point since 1946 * we apparently have an otherwise valid VM state 1947 */ 1948 } else { 1949 buf = g_malloc(0x1000); 1950 size = qemu_get_be32(f); 1951 1952 while (size > 0) { 1953 uint32_t read_chunk = MIN(size, 0x1000); 1954 qemu_get_buffer(f, buf, read_chunk); 1955 size -= read_chunk; 1956 } 1957 g_free(buf); 1958 } 1959 } 1960 1961 cpu_synchronize_all_post_init(); 1962 1963 return ret; 1964 } 1965 1966 void hmp_savevm(Monitor *mon, const QDict *qdict) 1967 { 1968 BlockDriverState *bs, *bs1; 1969 QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1; 1970 int ret; 1971 QEMUFile *f; 1972 int saved_vm_running; 1973 uint64_t vm_state_size; 1974 qemu_timeval tv; 1975 struct tm tm; 1976 const char *name = qdict_get_try_str(qdict, "name"); 1977 Error *local_err = NULL; 1978 AioContext *aio_context; 1979 1980 if (!bdrv_all_can_snapshot(&bs)) { 1981 monitor_printf(mon, "Device '%s' is writable but does not " 1982 "support snapshots.\n", bdrv_get_device_name(bs)); 1983 return; 1984 } 1985 1986 /* Delete old snapshots of the same name */ 1987 if (name && bdrv_all_delete_snapshot(name, &bs1, &local_err) < 0) { 1988 error_reportf_err(local_err, 1989 "Error while deleting snapshot on device '%s': ", 1990 bdrv_get_device_name(bs1)); 1991 return; 1992 } 1993 1994 bs = bdrv_all_find_vmstate_bs(); 1995 if (bs == NULL) { 1996 monitor_printf(mon, "No block device can accept snapshots\n"); 1997 return; 1998 } 1999 aio_context = bdrv_get_aio_context(bs); 2000 2001 saved_vm_running = runstate_is_running(); 2002 2003 ret = global_state_store(); 2004 if (ret) { 2005 monitor_printf(mon, "Error saving global state\n"); 2006 return; 2007 } 2008 vm_stop(RUN_STATE_SAVE_VM); 2009 2010 aio_context_acquire(aio_context); 2011 2012 memset(sn, 0, sizeof(*sn)); 2013 2014 /* fill auxiliary fields */ 2015 qemu_gettimeofday(&tv); 2016 sn->date_sec = tv.tv_sec; 2017 sn->date_nsec = tv.tv_usec * 1000; 2018 sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 2019 2020 if (name) { 2021 ret = bdrv_snapshot_find(bs, old_sn, name); 2022 if (ret >= 0) { 2023 pstrcpy(sn->name, sizeof(sn->name), old_sn->name); 2024 pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str); 2025 } else { 2026 pstrcpy(sn->name, sizeof(sn->name), name); 2027 } 2028 } else { 2029 /* cast below needed for OpenBSD where tv_sec is still 'long' */ 2030 localtime_r((const time_t *)&tv.tv_sec, &tm); 2031 strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm); 2032 } 2033 2034 /* save the VM state */ 2035 f = qemu_fopen_bdrv(bs, 1); 2036 if (!f) { 2037 monitor_printf(mon, "Could not open VM state file\n"); 2038 goto the_end; 2039 } 2040 ret = qemu_savevm_state(f, &local_err); 2041 vm_state_size = qemu_ftell(f); 2042 qemu_fclose(f); 2043 if (ret < 0) { 2044 error_report_err(local_err); 2045 goto the_end; 2046 } 2047 2048 ret = bdrv_all_create_snapshot(sn, bs, vm_state_size, &bs); 2049 if (ret < 0) { 2050 monitor_printf(mon, "Error while creating snapshot on '%s'\n", 2051 bdrv_get_device_name(bs)); 2052 } 2053 2054 the_end: 2055 aio_context_release(aio_context); 2056 if (saved_vm_running) { 2057 vm_start(); 2058 } 2059 } 2060 2061 void qmp_xen_save_devices_state(const char *filename, Error **errp) 2062 { 2063 QEMUFile *f; 2064 int saved_vm_running; 2065 int ret; 2066 2067 saved_vm_running = runstate_is_running(); 2068 vm_stop(RUN_STATE_SAVE_VM); 2069 global_state_store_running(); 2070 2071 f = qemu_fopen(filename, "wb"); 2072 if (!f) { 2073 error_setg_file_open(errp, errno, filename); 2074 goto the_end; 2075 } 2076 ret = qemu_save_device_state(f); 2077 qemu_fclose(f); 2078 if (ret < 0) { 2079 error_setg(errp, QERR_IO_ERROR); 2080 } 2081 2082 the_end: 2083 if (saved_vm_running) { 2084 vm_start(); 2085 } 2086 } 2087 2088 int load_vmstate(const char *name) 2089 { 2090 BlockDriverState *bs, *bs_vm_state; 2091 QEMUSnapshotInfo sn; 2092 QEMUFile *f; 2093 int ret; 2094 AioContext *aio_context; 2095 2096 if (!bdrv_all_can_snapshot(&bs)) { 2097 error_report("Device '%s' is writable but does not support snapshots.", 2098 bdrv_get_device_name(bs)); 2099 return -ENOTSUP; 2100 } 2101 ret = bdrv_all_find_snapshot(name, &bs); 2102 if (ret < 0) { 2103 error_report("Device '%s' does not have the requested snapshot '%s'", 2104 bdrv_get_device_name(bs), name); 2105 return ret; 2106 } 2107 2108 bs_vm_state = bdrv_all_find_vmstate_bs(); 2109 if (!bs_vm_state) { 2110 error_report("No block device supports snapshots"); 2111 return -ENOTSUP; 2112 } 2113 aio_context = bdrv_get_aio_context(bs_vm_state); 2114 2115 /* Don't even try to load empty VM states */ 2116 aio_context_acquire(aio_context); 2117 ret = bdrv_snapshot_find(bs_vm_state, &sn, name); 2118 aio_context_release(aio_context); 2119 if (ret < 0) { 2120 return ret; 2121 } else if (sn.vm_state_size == 0) { 2122 error_report("This is a disk-only snapshot. Revert to it offline " 2123 "using qemu-img."); 2124 return -EINVAL; 2125 } 2126 2127 /* Flush all IO requests so they don't interfere with the new state. */ 2128 bdrv_drain_all(); 2129 2130 ret = bdrv_all_goto_snapshot(name, &bs); 2131 if (ret < 0) { 2132 error_report("Error %d while activating snapshot '%s' on '%s'", 2133 ret, name, bdrv_get_device_name(bs)); 2134 return ret; 2135 } 2136 2137 /* restore the VM state */ 2138 f = qemu_fopen_bdrv(bs_vm_state, 0); 2139 if (!f) { 2140 error_report("Could not open VM state file"); 2141 return -EINVAL; 2142 } 2143 2144 qemu_system_reset(VMRESET_SILENT); 2145 migration_incoming_state_new(f); 2146 2147 aio_context_acquire(aio_context); 2148 ret = qemu_loadvm_state(f); 2149 qemu_fclose(f); 2150 aio_context_release(aio_context); 2151 2152 migration_incoming_state_destroy(); 2153 if (ret < 0) { 2154 error_report("Error %d while loading VM state", ret); 2155 return ret; 2156 } 2157 2158 return 0; 2159 } 2160 2161 void hmp_delvm(Monitor *mon, const QDict *qdict) 2162 { 2163 BlockDriverState *bs; 2164 Error *err; 2165 const char *name = qdict_get_str(qdict, "name"); 2166 2167 if (bdrv_all_delete_snapshot(name, &bs, &err) < 0) { 2168 error_reportf_err(err, 2169 "Error while deleting snapshot on device '%s': ", 2170 bdrv_get_device_name(bs)); 2171 } 2172 } 2173 2174 void hmp_info_snapshots(Monitor *mon, const QDict *qdict) 2175 { 2176 BlockDriverState *bs, *bs1; 2177 QEMUSnapshotInfo *sn_tab, *sn; 2178 int nb_sns, i; 2179 int total; 2180 int *available_snapshots; 2181 AioContext *aio_context; 2182 2183 bs = bdrv_all_find_vmstate_bs(); 2184 if (!bs) { 2185 monitor_printf(mon, "No available block device supports snapshots\n"); 2186 return; 2187 } 2188 aio_context = bdrv_get_aio_context(bs); 2189 2190 aio_context_acquire(aio_context); 2191 nb_sns = bdrv_snapshot_list(bs, &sn_tab); 2192 aio_context_release(aio_context); 2193 2194 if (nb_sns < 0) { 2195 monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns); 2196 return; 2197 } 2198 2199 if (nb_sns == 0) { 2200 monitor_printf(mon, "There is no snapshot available.\n"); 2201 return; 2202 } 2203 2204 available_snapshots = g_new0(int, nb_sns); 2205 total = 0; 2206 for (i = 0; i < nb_sns; i++) { 2207 if (bdrv_all_find_snapshot(sn_tab[i].id_str, &bs1) == 0) { 2208 available_snapshots[total] = i; 2209 total++; 2210 } 2211 } 2212 2213 if (total > 0) { 2214 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL); 2215 monitor_printf(mon, "\n"); 2216 for (i = 0; i < total; i++) { 2217 sn = &sn_tab[available_snapshots[i]]; 2218 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn); 2219 monitor_printf(mon, "\n"); 2220 } 2221 } else { 2222 monitor_printf(mon, "There is no suitable snapshot available\n"); 2223 } 2224 2225 g_free(sn_tab); 2226 g_free(available_snapshots); 2227 2228 } 2229 2230 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev) 2231 { 2232 qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK, 2233 memory_region_name(mr), dev); 2234 } 2235 2236 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev) 2237 { 2238 qemu_ram_unset_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK); 2239 } 2240 2241 void vmstate_register_ram_global(MemoryRegion *mr) 2242 { 2243 vmstate_register_ram(mr, NULL); 2244 } 2245