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 "cpu.h" 31 #include "hw/boards.h" 32 #include "hw/hw.h" 33 #include "hw/qdev.h" 34 #include "hw/xen/xen.h" 35 #include "net/net.h" 36 #include "monitor/monitor.h" 37 #include "sysemu/sysemu.h" 38 #include "qemu/timer.h" 39 #include "audio/audio.h" 40 #include "migration/migration.h" 41 #include "migration/postcopy-ram.h" 42 #include "qapi/qmp/qerror.h" 43 #include "qemu/error-report.h" 44 #include "qemu/sockets.h" 45 #include "qemu/queue.h" 46 #include "sysemu/cpus.h" 47 #include "exec/memory.h" 48 #include "qmp-commands.h" 49 #include "trace.h" 50 #include "qemu/bitops.h" 51 #include "qemu/iov.h" 52 #include "block/snapshot.h" 53 #include "block/qapi.h" 54 #include "qemu/cutils.h" 55 #include "io/channel-buffer.h" 56 #include "io/channel-file.h" 57 58 #ifndef ETH_P_RARP 59 #define ETH_P_RARP 0x8035 60 #endif 61 #define ARP_HTYPE_ETH 0x0001 62 #define ARP_PTYPE_IP 0x0800 63 #define ARP_OP_REQUEST_REV 0x3 64 65 const unsigned int postcopy_ram_discard_version = 0; 66 67 static bool skip_section_footers; 68 69 static struct mig_cmd_args { 70 ssize_t len; /* -1 = variable */ 71 const char *name; 72 } mig_cmd_args[] = { 73 [MIG_CMD_INVALID] = { .len = -1, .name = "INVALID" }, 74 [MIG_CMD_OPEN_RETURN_PATH] = { .len = 0, .name = "OPEN_RETURN_PATH" }, 75 [MIG_CMD_PING] = { .len = sizeof(uint32_t), .name = "PING" }, 76 [MIG_CMD_POSTCOPY_ADVISE] = { .len = 16, .name = "POSTCOPY_ADVISE" }, 77 [MIG_CMD_POSTCOPY_LISTEN] = { .len = 0, .name = "POSTCOPY_LISTEN" }, 78 [MIG_CMD_POSTCOPY_RUN] = { .len = 0, .name = "POSTCOPY_RUN" }, 79 [MIG_CMD_POSTCOPY_RAM_DISCARD] = { 80 .len = -1, .name = "POSTCOPY_RAM_DISCARD" }, 81 [MIG_CMD_PACKAGED] = { .len = 4, .name = "PACKAGED" }, 82 [MIG_CMD_MAX] = { .len = -1, .name = "MAX" }, 83 }; 84 85 static int announce_self_create(uint8_t *buf, 86 uint8_t *mac_addr) 87 { 88 /* Ethernet header. */ 89 memset(buf, 0xff, 6); /* destination MAC addr */ 90 memcpy(buf + 6, mac_addr, 6); /* source MAC addr */ 91 *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */ 92 93 /* RARP header. */ 94 *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */ 95 *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */ 96 *(buf + 18) = 6; /* hardware addr length (ethernet) */ 97 *(buf + 19) = 4; /* protocol addr length (IPv4) */ 98 *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */ 99 memcpy(buf + 22, mac_addr, 6); /* source hw addr */ 100 memset(buf + 28, 0x00, 4); /* source protocol addr */ 101 memcpy(buf + 32, mac_addr, 6); /* target hw addr */ 102 memset(buf + 38, 0x00, 4); /* target protocol addr */ 103 104 /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */ 105 memset(buf + 42, 0x00, 18); 106 107 return 60; /* len (FCS will be added by hardware) */ 108 } 109 110 static void qemu_announce_self_iter(NICState *nic, void *opaque) 111 { 112 uint8_t buf[60]; 113 int len; 114 115 trace_qemu_announce_self_iter(qemu_ether_ntoa(&nic->conf->macaddr)); 116 len = announce_self_create(buf, nic->conf->macaddr.a); 117 118 qemu_send_packet_raw(qemu_get_queue(nic), buf, len); 119 } 120 121 122 static void qemu_announce_self_once(void *opaque) 123 { 124 static int count = SELF_ANNOUNCE_ROUNDS; 125 QEMUTimer *timer = *(QEMUTimer **)opaque; 126 127 qemu_foreach_nic(qemu_announce_self_iter, NULL); 128 129 if (--count) { 130 /* delay 50ms, 150ms, 250ms, ... */ 131 timer_mod(timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 132 self_announce_delay(count)); 133 } else { 134 timer_del(timer); 135 timer_free(timer); 136 } 137 } 138 139 void qemu_announce_self(void) 140 { 141 static QEMUTimer *timer; 142 timer = timer_new_ms(QEMU_CLOCK_REALTIME, qemu_announce_self_once, &timer); 143 qemu_announce_self_once(&timer); 144 } 145 146 /***********************************************************/ 147 /* savevm/loadvm support */ 148 149 static ssize_t block_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, 150 int64_t pos) 151 { 152 int ret; 153 QEMUIOVector qiov; 154 155 qemu_iovec_init_external(&qiov, iov, iovcnt); 156 ret = bdrv_writev_vmstate(opaque, &qiov, pos); 157 if (ret < 0) { 158 return ret; 159 } 160 161 return qiov.size; 162 } 163 164 static ssize_t block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, 165 size_t size) 166 { 167 return bdrv_load_vmstate(opaque, buf, pos, size); 168 } 169 170 static int bdrv_fclose(void *opaque) 171 { 172 return bdrv_flush(opaque); 173 } 174 175 static const QEMUFileOps bdrv_read_ops = { 176 .get_buffer = block_get_buffer, 177 .close = bdrv_fclose 178 }; 179 180 static const QEMUFileOps bdrv_write_ops = { 181 .writev_buffer = block_writev_buffer, 182 .close = bdrv_fclose 183 }; 184 185 static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable) 186 { 187 if (is_writable) { 188 return qemu_fopen_ops(bs, &bdrv_write_ops); 189 } 190 return qemu_fopen_ops(bs, &bdrv_read_ops); 191 } 192 193 194 /* QEMUFile timer support. 195 * Not in qemu-file.c to not add qemu-timer.c as dependency to qemu-file.c 196 */ 197 198 void timer_put(QEMUFile *f, QEMUTimer *ts) 199 { 200 uint64_t expire_time; 201 202 expire_time = timer_expire_time_ns(ts); 203 qemu_put_be64(f, expire_time); 204 } 205 206 void timer_get(QEMUFile *f, QEMUTimer *ts) 207 { 208 uint64_t expire_time; 209 210 expire_time = qemu_get_be64(f); 211 if (expire_time != -1) { 212 timer_mod_ns(ts, expire_time); 213 } else { 214 timer_del(ts); 215 } 216 } 217 218 219 /* VMState timer support. 220 * Not in vmstate.c to not add qemu-timer.c as dependency to vmstate.c 221 */ 222 223 static int get_timer(QEMUFile *f, void *pv, size_t size, VMStateField *field) 224 { 225 QEMUTimer *v = pv; 226 timer_get(f, v); 227 return 0; 228 } 229 230 static int put_timer(QEMUFile *f, void *pv, size_t size, VMStateField *field, 231 QJSON *vmdesc) 232 { 233 QEMUTimer *v = pv; 234 timer_put(f, v); 235 236 return 0; 237 } 238 239 const VMStateInfo vmstate_info_timer = { 240 .name = "timer", 241 .get = get_timer, 242 .put = put_timer, 243 }; 244 245 246 typedef struct CompatEntry { 247 char idstr[256]; 248 int instance_id; 249 } CompatEntry; 250 251 typedef struct SaveStateEntry { 252 QTAILQ_ENTRY(SaveStateEntry) entry; 253 char idstr[256]; 254 int instance_id; 255 int alias_id; 256 int version_id; 257 int section_id; 258 SaveVMHandlers *ops; 259 const VMStateDescription *vmsd; 260 void *opaque; 261 CompatEntry *compat; 262 int is_ram; 263 } SaveStateEntry; 264 265 typedef struct SaveState { 266 QTAILQ_HEAD(, SaveStateEntry) handlers; 267 int global_section_id; 268 bool skip_configuration; 269 uint32_t len; 270 const char *name; 271 uint32_t target_page_bits; 272 } SaveState; 273 274 static SaveState savevm_state = { 275 .handlers = QTAILQ_HEAD_INITIALIZER(savevm_state.handlers), 276 .global_section_id = 0, 277 .skip_configuration = false, 278 }; 279 280 void savevm_skip_configuration(void) 281 { 282 savevm_state.skip_configuration = true; 283 } 284 285 286 static void configuration_pre_save(void *opaque) 287 { 288 SaveState *state = opaque; 289 const char *current_name = MACHINE_GET_CLASS(current_machine)->name; 290 291 state->len = strlen(current_name); 292 state->name = current_name; 293 state->target_page_bits = TARGET_PAGE_BITS; 294 } 295 296 static int configuration_pre_load(void *opaque) 297 { 298 SaveState *state = opaque; 299 300 /* If there is no target-page-bits subsection it means the source 301 * predates the variable-target-page-bits support and is using the 302 * minimum possible value for this CPU. 303 */ 304 state->target_page_bits = TARGET_PAGE_BITS_MIN; 305 return 0; 306 } 307 308 static int configuration_post_load(void *opaque, int version_id) 309 { 310 SaveState *state = opaque; 311 const char *current_name = MACHINE_GET_CLASS(current_machine)->name; 312 313 if (strncmp(state->name, current_name, state->len) != 0) { 314 error_report("Machine type received is '%.*s' and local is '%s'", 315 (int) state->len, state->name, current_name); 316 return -EINVAL; 317 } 318 319 if (state->target_page_bits != TARGET_PAGE_BITS) { 320 error_report("Received TARGET_PAGE_BITS is %d but local is %d", 321 state->target_page_bits, TARGET_PAGE_BITS); 322 return -EINVAL; 323 } 324 325 return 0; 326 } 327 328 /* The target-page-bits subsection is present only if the 329 * target page size is not the same as the default (ie the 330 * minimum page size for a variable-page-size guest CPU). 331 * If it is present then it contains the actual target page 332 * bits for the machine, and migration will fail if the 333 * two ends don't agree about it. 334 */ 335 static bool vmstate_target_page_bits_needed(void *opaque) 336 { 337 return TARGET_PAGE_BITS > TARGET_PAGE_BITS_MIN; 338 } 339 340 static const VMStateDescription vmstate_target_page_bits = { 341 .name = "configuration/target-page-bits", 342 .version_id = 1, 343 .minimum_version_id = 1, 344 .needed = vmstate_target_page_bits_needed, 345 .fields = (VMStateField[]) { 346 VMSTATE_UINT32(target_page_bits, SaveState), 347 VMSTATE_END_OF_LIST() 348 } 349 }; 350 351 static const VMStateDescription vmstate_configuration = { 352 .name = "configuration", 353 .version_id = 1, 354 .pre_load = configuration_pre_load, 355 .post_load = configuration_post_load, 356 .pre_save = configuration_pre_save, 357 .fields = (VMStateField[]) { 358 VMSTATE_UINT32(len, SaveState), 359 VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, 0, len), 360 VMSTATE_END_OF_LIST() 361 }, 362 .subsections = (const VMStateDescription*[]) { 363 &vmstate_target_page_bits, 364 NULL 365 } 366 }; 367 368 static void dump_vmstate_vmsd(FILE *out_file, 369 const VMStateDescription *vmsd, int indent, 370 bool is_subsection); 371 372 static void dump_vmstate_vmsf(FILE *out_file, const VMStateField *field, 373 int indent) 374 { 375 fprintf(out_file, "%*s{\n", indent, ""); 376 indent += 2; 377 fprintf(out_file, "%*s\"field\": \"%s\",\n", indent, "", field->name); 378 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 379 field->version_id); 380 fprintf(out_file, "%*s\"field_exists\": %s,\n", indent, "", 381 field->field_exists ? "true" : "false"); 382 fprintf(out_file, "%*s\"size\": %zu", indent, "", field->size); 383 if (field->vmsd != NULL) { 384 fprintf(out_file, ",\n"); 385 dump_vmstate_vmsd(out_file, field->vmsd, indent, false); 386 } 387 fprintf(out_file, "\n%*s}", indent - 2, ""); 388 } 389 390 static void dump_vmstate_vmss(FILE *out_file, 391 const VMStateDescription **subsection, 392 int indent) 393 { 394 if (*subsection != NULL) { 395 dump_vmstate_vmsd(out_file, *subsection, indent, true); 396 } 397 } 398 399 static void dump_vmstate_vmsd(FILE *out_file, 400 const VMStateDescription *vmsd, int indent, 401 bool is_subsection) 402 { 403 if (is_subsection) { 404 fprintf(out_file, "%*s{\n", indent, ""); 405 } else { 406 fprintf(out_file, "%*s\"%s\": {\n", indent, "", "Description"); 407 } 408 indent += 2; 409 fprintf(out_file, "%*s\"name\": \"%s\",\n", indent, "", vmsd->name); 410 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 411 vmsd->version_id); 412 fprintf(out_file, "%*s\"minimum_version_id\": %d", indent, "", 413 vmsd->minimum_version_id); 414 if (vmsd->fields != NULL) { 415 const VMStateField *field = vmsd->fields; 416 bool first; 417 418 fprintf(out_file, ",\n%*s\"Fields\": [\n", indent, ""); 419 first = true; 420 while (field->name != NULL) { 421 if (field->flags & VMS_MUST_EXIST) { 422 /* Ignore VMSTATE_VALIDATE bits; these don't get migrated */ 423 field++; 424 continue; 425 } 426 if (!first) { 427 fprintf(out_file, ",\n"); 428 } 429 dump_vmstate_vmsf(out_file, field, indent + 2); 430 field++; 431 first = false; 432 } 433 fprintf(out_file, "\n%*s]", indent, ""); 434 } 435 if (vmsd->subsections != NULL) { 436 const VMStateDescription **subsection = vmsd->subsections; 437 bool first; 438 439 fprintf(out_file, ",\n%*s\"Subsections\": [\n", indent, ""); 440 first = true; 441 while (*subsection != NULL) { 442 if (!first) { 443 fprintf(out_file, ",\n"); 444 } 445 dump_vmstate_vmss(out_file, subsection, indent + 2); 446 subsection++; 447 first = false; 448 } 449 fprintf(out_file, "\n%*s]", indent, ""); 450 } 451 fprintf(out_file, "\n%*s}", indent - 2, ""); 452 } 453 454 static void dump_machine_type(FILE *out_file) 455 { 456 MachineClass *mc; 457 458 mc = MACHINE_GET_CLASS(current_machine); 459 460 fprintf(out_file, " \"vmschkmachine\": {\n"); 461 fprintf(out_file, " \"Name\": \"%s\"\n", mc->name); 462 fprintf(out_file, " },\n"); 463 } 464 465 void dump_vmstate_json_to_file(FILE *out_file) 466 { 467 GSList *list, *elt; 468 bool first; 469 470 fprintf(out_file, "{\n"); 471 dump_machine_type(out_file); 472 473 first = true; 474 list = object_class_get_list(TYPE_DEVICE, true); 475 for (elt = list; elt; elt = elt->next) { 476 DeviceClass *dc = OBJECT_CLASS_CHECK(DeviceClass, elt->data, 477 TYPE_DEVICE); 478 const char *name; 479 int indent = 2; 480 481 if (!dc->vmsd) { 482 continue; 483 } 484 485 if (!first) { 486 fprintf(out_file, ",\n"); 487 } 488 name = object_class_get_name(OBJECT_CLASS(dc)); 489 fprintf(out_file, "%*s\"%s\": {\n", indent, "", name); 490 indent += 2; 491 fprintf(out_file, "%*s\"Name\": \"%s\",\n", indent, "", name); 492 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 493 dc->vmsd->version_id); 494 fprintf(out_file, "%*s\"minimum_version_id\": %d,\n", indent, "", 495 dc->vmsd->minimum_version_id); 496 497 dump_vmstate_vmsd(out_file, dc->vmsd, indent, false); 498 499 fprintf(out_file, "\n%*s}", indent - 2, ""); 500 first = false; 501 } 502 fprintf(out_file, "\n}\n"); 503 fclose(out_file); 504 } 505 506 static int calculate_new_instance_id(const char *idstr) 507 { 508 SaveStateEntry *se; 509 int instance_id = 0; 510 511 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 512 if (strcmp(idstr, se->idstr) == 0 513 && instance_id <= se->instance_id) { 514 instance_id = se->instance_id + 1; 515 } 516 } 517 return instance_id; 518 } 519 520 static int calculate_compat_instance_id(const char *idstr) 521 { 522 SaveStateEntry *se; 523 int instance_id = 0; 524 525 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 526 if (!se->compat) { 527 continue; 528 } 529 530 if (strcmp(idstr, se->compat->idstr) == 0 531 && instance_id <= se->compat->instance_id) { 532 instance_id = se->compat->instance_id + 1; 533 } 534 } 535 return instance_id; 536 } 537 538 static inline MigrationPriority save_state_priority(SaveStateEntry *se) 539 { 540 if (se->vmsd) { 541 return se->vmsd->priority; 542 } 543 return MIG_PRI_DEFAULT; 544 } 545 546 static void savevm_state_handler_insert(SaveStateEntry *nse) 547 { 548 MigrationPriority priority = save_state_priority(nse); 549 SaveStateEntry *se; 550 551 assert(priority <= MIG_PRI_MAX); 552 553 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 554 if (save_state_priority(se) < priority) { 555 break; 556 } 557 } 558 559 if (se) { 560 QTAILQ_INSERT_BEFORE(se, nse, entry); 561 } else { 562 QTAILQ_INSERT_TAIL(&savevm_state.handlers, nse, entry); 563 } 564 } 565 566 /* TODO: Individual devices generally have very little idea about the rest 567 of the system, so instance_id should be removed/replaced. 568 Meanwhile pass -1 as instance_id if you do not already have a clearly 569 distinguishing id for all instances of your device class. */ 570 int register_savevm_live(DeviceState *dev, 571 const char *idstr, 572 int instance_id, 573 int version_id, 574 SaveVMHandlers *ops, 575 void *opaque) 576 { 577 SaveStateEntry *se; 578 579 se = g_new0(SaveStateEntry, 1); 580 se->version_id = version_id; 581 se->section_id = savevm_state.global_section_id++; 582 se->ops = ops; 583 se->opaque = opaque; 584 se->vmsd = NULL; 585 /* if this is a live_savem then set is_ram */ 586 if (ops->save_live_setup != NULL) { 587 se->is_ram = 1; 588 } 589 590 if (dev) { 591 char *id = qdev_get_dev_path(dev); 592 if (id) { 593 pstrcpy(se->idstr, sizeof(se->idstr), id); 594 pstrcat(se->idstr, sizeof(se->idstr), "/"); 595 g_free(id); 596 597 se->compat = g_new0(CompatEntry, 1); 598 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr); 599 se->compat->instance_id = instance_id == -1 ? 600 calculate_compat_instance_id(idstr) : instance_id; 601 instance_id = -1; 602 } 603 } 604 pstrcat(se->idstr, sizeof(se->idstr), idstr); 605 606 if (instance_id == -1) { 607 se->instance_id = calculate_new_instance_id(se->idstr); 608 } else { 609 se->instance_id = instance_id; 610 } 611 assert(!se->compat || se->instance_id == 0); 612 savevm_state_handler_insert(se); 613 return 0; 614 } 615 616 int register_savevm(DeviceState *dev, 617 const char *idstr, 618 int instance_id, 619 int version_id, 620 SaveStateHandler *save_state, 621 LoadStateHandler *load_state, 622 void *opaque) 623 { 624 SaveVMHandlers *ops = g_new0(SaveVMHandlers, 1); 625 ops->save_state = save_state; 626 ops->load_state = load_state; 627 return register_savevm_live(dev, idstr, instance_id, version_id, 628 ops, opaque); 629 } 630 631 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque) 632 { 633 SaveStateEntry *se, *new_se; 634 char id[256] = ""; 635 636 if (dev) { 637 char *path = qdev_get_dev_path(dev); 638 if (path) { 639 pstrcpy(id, sizeof(id), path); 640 pstrcat(id, sizeof(id), "/"); 641 g_free(path); 642 } 643 } 644 pstrcat(id, sizeof(id), idstr); 645 646 QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { 647 if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) { 648 QTAILQ_REMOVE(&savevm_state.handlers, se, entry); 649 g_free(se->compat); 650 g_free(se->ops); 651 g_free(se); 652 } 653 } 654 } 655 656 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id, 657 const VMStateDescription *vmsd, 658 void *opaque, int alias_id, 659 int required_for_version) 660 { 661 SaveStateEntry *se; 662 663 /* If this triggers, alias support can be dropped for the vmsd. */ 664 assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id); 665 666 se = g_new0(SaveStateEntry, 1); 667 se->version_id = vmsd->version_id; 668 se->section_id = savevm_state.global_section_id++; 669 se->opaque = opaque; 670 se->vmsd = vmsd; 671 se->alias_id = alias_id; 672 673 if (dev) { 674 char *id = qdev_get_dev_path(dev); 675 if (id) { 676 pstrcpy(se->idstr, sizeof(se->idstr), id); 677 pstrcat(se->idstr, sizeof(se->idstr), "/"); 678 g_free(id); 679 680 se->compat = g_new0(CompatEntry, 1); 681 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name); 682 se->compat->instance_id = instance_id == -1 ? 683 calculate_compat_instance_id(vmsd->name) : instance_id; 684 instance_id = -1; 685 } 686 } 687 pstrcat(se->idstr, sizeof(se->idstr), vmsd->name); 688 689 if (instance_id == -1) { 690 se->instance_id = calculate_new_instance_id(se->idstr); 691 } else { 692 se->instance_id = instance_id; 693 } 694 assert(!se->compat || se->instance_id == 0); 695 savevm_state_handler_insert(se); 696 return 0; 697 } 698 699 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd, 700 void *opaque) 701 { 702 SaveStateEntry *se, *new_se; 703 704 QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { 705 if (se->vmsd == vmsd && se->opaque == opaque) { 706 QTAILQ_REMOVE(&savevm_state.handlers, se, entry); 707 g_free(se->compat); 708 g_free(se); 709 } 710 } 711 } 712 713 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) 714 { 715 trace_vmstate_load(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); 716 if (!se->vmsd) { /* Old style */ 717 return se->ops->load_state(f, se->opaque, version_id); 718 } 719 return vmstate_load_state(f, se->vmsd, se->opaque, version_id); 720 } 721 722 static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) 723 { 724 int64_t old_offset, size; 725 726 old_offset = qemu_ftell_fast(f); 727 se->ops->save_state(f, se->opaque); 728 size = qemu_ftell_fast(f) - old_offset; 729 730 if (vmdesc) { 731 json_prop_int(vmdesc, "size", size); 732 json_start_array(vmdesc, "fields"); 733 json_start_object(vmdesc, NULL); 734 json_prop_str(vmdesc, "name", "data"); 735 json_prop_int(vmdesc, "size", size); 736 json_prop_str(vmdesc, "type", "buffer"); 737 json_end_object(vmdesc); 738 json_end_array(vmdesc); 739 } 740 } 741 742 static void vmstate_save(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) 743 { 744 trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); 745 if (!se->vmsd) { 746 vmstate_save_old_style(f, se, vmdesc); 747 return; 748 } 749 vmstate_save_state(f, se->vmsd, se->opaque, vmdesc); 750 } 751 752 void savevm_skip_section_footers(void) 753 { 754 skip_section_footers = true; 755 } 756 757 /* 758 * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL) 759 */ 760 static void save_section_header(QEMUFile *f, SaveStateEntry *se, 761 uint8_t section_type) 762 { 763 qemu_put_byte(f, section_type); 764 qemu_put_be32(f, se->section_id); 765 766 if (section_type == QEMU_VM_SECTION_FULL || 767 section_type == QEMU_VM_SECTION_START) { 768 /* ID string */ 769 size_t len = strlen(se->idstr); 770 qemu_put_byte(f, len); 771 qemu_put_buffer(f, (uint8_t *)se->idstr, len); 772 773 qemu_put_be32(f, se->instance_id); 774 qemu_put_be32(f, se->version_id); 775 } 776 } 777 778 /* 779 * Write a footer onto device sections that catches cases misformatted device 780 * sections. 781 */ 782 static void save_section_footer(QEMUFile *f, SaveStateEntry *se) 783 { 784 if (!skip_section_footers) { 785 qemu_put_byte(f, QEMU_VM_SECTION_FOOTER); 786 qemu_put_be32(f, se->section_id); 787 } 788 } 789 790 /** 791 * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the 792 * command and associated data. 793 * 794 * @f: File to send command on 795 * @command: Command type to send 796 * @len: Length of associated data 797 * @data: Data associated with command. 798 */ 799 void qemu_savevm_command_send(QEMUFile *f, 800 enum qemu_vm_cmd command, 801 uint16_t len, 802 uint8_t *data) 803 { 804 trace_savevm_command_send(command, len); 805 qemu_put_byte(f, QEMU_VM_COMMAND); 806 qemu_put_be16(f, (uint16_t)command); 807 qemu_put_be16(f, len); 808 qemu_put_buffer(f, data, len); 809 qemu_fflush(f); 810 } 811 812 void qemu_savevm_send_ping(QEMUFile *f, uint32_t value) 813 { 814 uint32_t buf; 815 816 trace_savevm_send_ping(value); 817 buf = cpu_to_be32(value); 818 qemu_savevm_command_send(f, MIG_CMD_PING, sizeof(value), (uint8_t *)&buf); 819 } 820 821 void qemu_savevm_send_open_return_path(QEMUFile *f) 822 { 823 trace_savevm_send_open_return_path(); 824 qemu_savevm_command_send(f, MIG_CMD_OPEN_RETURN_PATH, 0, NULL); 825 } 826 827 /* We have a buffer of data to send; we don't want that all to be loaded 828 * by the command itself, so the command contains just the length of the 829 * extra buffer that we then send straight after it. 830 * TODO: Must be a better way to organise that 831 * 832 * Returns: 833 * 0 on success 834 * -ve on error 835 */ 836 int qemu_savevm_send_packaged(QEMUFile *f, const uint8_t *buf, size_t len) 837 { 838 uint32_t tmp; 839 840 if (len > MAX_VM_CMD_PACKAGED_SIZE) { 841 error_report("%s: Unreasonably large packaged state: %zu", 842 __func__, len); 843 return -1; 844 } 845 846 tmp = cpu_to_be32(len); 847 848 trace_qemu_savevm_send_packaged(); 849 qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); 850 851 qemu_put_buffer(f, buf, len); 852 853 return 0; 854 } 855 856 /* Send prior to any postcopy transfer */ 857 void qemu_savevm_send_postcopy_advise(QEMUFile *f) 858 { 859 uint64_t tmp[2]; 860 tmp[0] = cpu_to_be64(getpagesize()); 861 tmp[1] = cpu_to_be64(1ul << qemu_target_page_bits()); 862 863 trace_qemu_savevm_send_postcopy_advise(); 864 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_ADVISE, 16, (uint8_t *)tmp); 865 } 866 867 /* Sent prior to starting the destination running in postcopy, discard pages 868 * that have already been sent but redirtied on the source. 869 * CMD_POSTCOPY_RAM_DISCARD consist of: 870 * byte version (0) 871 * byte Length of name field (not including 0) 872 * n x byte RAM block name 873 * byte 0 terminator (just for safety) 874 * n x Byte ranges within the named RAMBlock 875 * be64 Start of the range 876 * be64 Length 877 * 878 * name: RAMBlock name that these entries are part of 879 * len: Number of page entries 880 * start_list: 'len' addresses 881 * length_list: 'len' addresses 882 * 883 */ 884 void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name, 885 uint16_t len, 886 uint64_t *start_list, 887 uint64_t *length_list) 888 { 889 uint8_t *buf; 890 uint16_t tmplen; 891 uint16_t t; 892 size_t name_len = strlen(name); 893 894 trace_qemu_savevm_send_postcopy_ram_discard(name, len); 895 assert(name_len < 256); 896 buf = g_malloc0(1 + 1 + name_len + 1 + (8 + 8) * len); 897 buf[0] = postcopy_ram_discard_version; 898 buf[1] = name_len; 899 memcpy(buf + 2, name, name_len); 900 tmplen = 2 + name_len; 901 buf[tmplen++] = '\0'; 902 903 for (t = 0; t < len; t++) { 904 stq_be_p(buf + tmplen, start_list[t]); 905 tmplen += 8; 906 stq_be_p(buf + tmplen, length_list[t]); 907 tmplen += 8; 908 } 909 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RAM_DISCARD, tmplen, buf); 910 g_free(buf); 911 } 912 913 /* Get the destination into a state where it can receive postcopy data. */ 914 void qemu_savevm_send_postcopy_listen(QEMUFile *f) 915 { 916 trace_savevm_send_postcopy_listen(); 917 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_LISTEN, 0, NULL); 918 } 919 920 /* Kick the destination into running */ 921 void qemu_savevm_send_postcopy_run(QEMUFile *f) 922 { 923 trace_savevm_send_postcopy_run(); 924 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RUN, 0, NULL); 925 } 926 927 bool qemu_savevm_state_blocked(Error **errp) 928 { 929 SaveStateEntry *se; 930 931 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 932 if (se->vmsd && se->vmsd->unmigratable) { 933 error_setg(errp, "State blocked by non-migratable device '%s'", 934 se->idstr); 935 return true; 936 } 937 } 938 return false; 939 } 940 941 static bool enforce_config_section(void) 942 { 943 MachineState *machine = MACHINE(qdev_get_machine()); 944 return machine->enforce_config_section; 945 } 946 947 void qemu_savevm_state_header(QEMUFile *f) 948 { 949 trace_savevm_state_header(); 950 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 951 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 952 953 if (!savevm_state.skip_configuration || enforce_config_section()) { 954 qemu_put_byte(f, QEMU_VM_CONFIGURATION); 955 vmstate_save_state(f, &vmstate_configuration, &savevm_state, 0); 956 } 957 958 } 959 960 void qemu_savevm_state_begin(QEMUFile *f, 961 const MigrationParams *params) 962 { 963 SaveStateEntry *se; 964 int ret; 965 966 trace_savevm_state_begin(); 967 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 968 if (!se->ops || !se->ops->set_params) { 969 continue; 970 } 971 se->ops->set_params(params, se->opaque); 972 } 973 974 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 975 if (!se->ops || !se->ops->save_live_setup) { 976 continue; 977 } 978 if (se->ops && se->ops->is_active) { 979 if (!se->ops->is_active(se->opaque)) { 980 continue; 981 } 982 } 983 save_section_header(f, se, QEMU_VM_SECTION_START); 984 985 ret = se->ops->save_live_setup(f, se->opaque); 986 save_section_footer(f, se); 987 if (ret < 0) { 988 qemu_file_set_error(f, ret); 989 break; 990 } 991 } 992 } 993 994 /* 995 * this function has three return values: 996 * negative: there was one error, and we have -errno. 997 * 0 : We haven't finished, caller have to go again 998 * 1 : We have finished, we can go to complete phase 999 */ 1000 int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy) 1001 { 1002 SaveStateEntry *se; 1003 int ret = 1; 1004 1005 trace_savevm_state_iterate(); 1006 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1007 if (!se->ops || !se->ops->save_live_iterate) { 1008 continue; 1009 } 1010 if (se->ops && se->ops->is_active) { 1011 if (!se->ops->is_active(se->opaque)) { 1012 continue; 1013 } 1014 } 1015 /* 1016 * In the postcopy phase, any device that doesn't know how to 1017 * do postcopy should have saved it's state in the _complete 1018 * call that's already run, it might get confused if we call 1019 * iterate afterwards. 1020 */ 1021 if (postcopy && !se->ops->save_live_complete_postcopy) { 1022 continue; 1023 } 1024 if (qemu_file_rate_limit(f)) { 1025 return 0; 1026 } 1027 trace_savevm_section_start(se->idstr, se->section_id); 1028 1029 save_section_header(f, se, QEMU_VM_SECTION_PART); 1030 1031 ret = se->ops->save_live_iterate(f, se->opaque); 1032 trace_savevm_section_end(se->idstr, se->section_id, ret); 1033 save_section_footer(f, se); 1034 1035 if (ret < 0) { 1036 qemu_file_set_error(f, ret); 1037 } 1038 if (ret <= 0) { 1039 /* Do not proceed to the next vmstate before this one reported 1040 completion of the current stage. This serializes the migration 1041 and reduces the probability that a faster changing state is 1042 synchronized over and over again. */ 1043 break; 1044 } 1045 } 1046 return ret; 1047 } 1048 1049 static bool should_send_vmdesc(void) 1050 { 1051 MachineState *machine = MACHINE(qdev_get_machine()); 1052 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 1053 return !machine->suppress_vmdesc && !in_postcopy; 1054 } 1055 1056 /* 1057 * Calls the save_live_complete_postcopy methods 1058 * causing the last few pages to be sent immediately and doing any associated 1059 * cleanup. 1060 * Note postcopy also calls qemu_savevm_state_complete_precopy to complete 1061 * all the other devices, but that happens at the point we switch to postcopy. 1062 */ 1063 void qemu_savevm_state_complete_postcopy(QEMUFile *f) 1064 { 1065 SaveStateEntry *se; 1066 int ret; 1067 1068 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1069 if (!se->ops || !se->ops->save_live_complete_postcopy) { 1070 continue; 1071 } 1072 if (se->ops && se->ops->is_active) { 1073 if (!se->ops->is_active(se->opaque)) { 1074 continue; 1075 } 1076 } 1077 trace_savevm_section_start(se->idstr, se->section_id); 1078 /* Section type */ 1079 qemu_put_byte(f, QEMU_VM_SECTION_END); 1080 qemu_put_be32(f, se->section_id); 1081 1082 ret = se->ops->save_live_complete_postcopy(f, se->opaque); 1083 trace_savevm_section_end(se->idstr, se->section_id, ret); 1084 save_section_footer(f, se); 1085 if (ret < 0) { 1086 qemu_file_set_error(f, ret); 1087 return; 1088 } 1089 } 1090 1091 qemu_put_byte(f, QEMU_VM_EOF); 1092 qemu_fflush(f); 1093 } 1094 1095 void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) 1096 { 1097 QJSON *vmdesc; 1098 int vmdesc_len; 1099 SaveStateEntry *se; 1100 int ret; 1101 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 1102 1103 trace_savevm_state_complete_precopy(); 1104 1105 cpu_synchronize_all_states(); 1106 1107 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1108 if (!se->ops || 1109 (in_postcopy && se->ops->save_live_complete_postcopy) || 1110 (in_postcopy && !iterable_only) || 1111 !se->ops->save_live_complete_precopy) { 1112 continue; 1113 } 1114 1115 if (se->ops && se->ops->is_active) { 1116 if (!se->ops->is_active(se->opaque)) { 1117 continue; 1118 } 1119 } 1120 trace_savevm_section_start(se->idstr, se->section_id); 1121 1122 save_section_header(f, se, QEMU_VM_SECTION_END); 1123 1124 ret = se->ops->save_live_complete_precopy(f, se->opaque); 1125 trace_savevm_section_end(se->idstr, se->section_id, ret); 1126 save_section_footer(f, se); 1127 if (ret < 0) { 1128 qemu_file_set_error(f, ret); 1129 return; 1130 } 1131 } 1132 1133 if (iterable_only) { 1134 return; 1135 } 1136 1137 vmdesc = qjson_new(); 1138 json_prop_int(vmdesc, "page_size", TARGET_PAGE_SIZE); 1139 json_start_array(vmdesc, "devices"); 1140 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1141 1142 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1143 continue; 1144 } 1145 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1146 trace_savevm_section_skip(se->idstr, se->section_id); 1147 continue; 1148 } 1149 1150 trace_savevm_section_start(se->idstr, se->section_id); 1151 1152 json_start_object(vmdesc, NULL); 1153 json_prop_str(vmdesc, "name", se->idstr); 1154 json_prop_int(vmdesc, "instance_id", se->instance_id); 1155 1156 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1157 vmstate_save(f, se, vmdesc); 1158 trace_savevm_section_end(se->idstr, se->section_id, 0); 1159 save_section_footer(f, se); 1160 1161 json_end_object(vmdesc); 1162 } 1163 1164 if (!in_postcopy) { 1165 /* Postcopy stream will still be going */ 1166 qemu_put_byte(f, QEMU_VM_EOF); 1167 } 1168 1169 json_end_array(vmdesc); 1170 qjson_finish(vmdesc); 1171 vmdesc_len = strlen(qjson_get_str(vmdesc)); 1172 1173 if (should_send_vmdesc()) { 1174 qemu_put_byte(f, QEMU_VM_VMDESCRIPTION); 1175 qemu_put_be32(f, vmdesc_len); 1176 qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len); 1177 } 1178 qjson_destroy(vmdesc); 1179 1180 qemu_fflush(f); 1181 } 1182 1183 /* Give an estimate of the amount left to be transferred, 1184 * the result is split into the amount for units that can and 1185 * for units that can't do postcopy. 1186 */ 1187 void qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size, 1188 uint64_t *res_non_postcopiable, 1189 uint64_t *res_postcopiable) 1190 { 1191 SaveStateEntry *se; 1192 1193 *res_non_postcopiable = 0; 1194 *res_postcopiable = 0; 1195 1196 1197 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1198 if (!se->ops || !se->ops->save_live_pending) { 1199 continue; 1200 } 1201 if (se->ops && se->ops->is_active) { 1202 if (!se->ops->is_active(se->opaque)) { 1203 continue; 1204 } 1205 } 1206 se->ops->save_live_pending(f, se->opaque, max_size, 1207 res_non_postcopiable, res_postcopiable); 1208 } 1209 } 1210 1211 void qemu_savevm_state_cleanup(void) 1212 { 1213 SaveStateEntry *se; 1214 1215 trace_savevm_state_cleanup(); 1216 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1217 if (se->ops && se->ops->cleanup) { 1218 se->ops->cleanup(se->opaque); 1219 } 1220 } 1221 } 1222 1223 static int qemu_savevm_state(QEMUFile *f, Error **errp) 1224 { 1225 int ret; 1226 MigrationParams params = { 1227 .blk = 0, 1228 .shared = 0 1229 }; 1230 MigrationState *ms = migrate_init(¶ms); 1231 MigrationStatus status; 1232 ms->to_dst_file = f; 1233 1234 if (migration_is_blocked(errp)) { 1235 ret = -EINVAL; 1236 goto done; 1237 } 1238 1239 qemu_mutex_unlock_iothread(); 1240 qemu_savevm_state_header(f); 1241 qemu_savevm_state_begin(f, ¶ms); 1242 qemu_mutex_lock_iothread(); 1243 1244 while (qemu_file_get_error(f) == 0) { 1245 if (qemu_savevm_state_iterate(f, false) > 0) { 1246 break; 1247 } 1248 } 1249 1250 ret = qemu_file_get_error(f); 1251 if (ret == 0) { 1252 qemu_savevm_state_complete_precopy(f, false); 1253 ret = qemu_file_get_error(f); 1254 } 1255 qemu_savevm_state_cleanup(); 1256 if (ret != 0) { 1257 error_setg_errno(errp, -ret, "Error while writing VM state"); 1258 } 1259 1260 done: 1261 if (ret != 0) { 1262 status = MIGRATION_STATUS_FAILED; 1263 } else { 1264 status = MIGRATION_STATUS_COMPLETED; 1265 } 1266 migrate_set_state(&ms->state, MIGRATION_STATUS_SETUP, status); 1267 return ret; 1268 } 1269 1270 static int qemu_save_device_state(QEMUFile *f) 1271 { 1272 SaveStateEntry *se; 1273 1274 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 1275 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 1276 1277 cpu_synchronize_all_states(); 1278 1279 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1280 if (se->is_ram) { 1281 continue; 1282 } 1283 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1284 continue; 1285 } 1286 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1287 continue; 1288 } 1289 1290 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1291 1292 vmstate_save(f, se, NULL); 1293 1294 save_section_footer(f, se); 1295 } 1296 1297 qemu_put_byte(f, QEMU_VM_EOF); 1298 1299 return qemu_file_get_error(f); 1300 } 1301 1302 static SaveStateEntry *find_se(const char *idstr, int instance_id) 1303 { 1304 SaveStateEntry *se; 1305 1306 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1307 if (!strcmp(se->idstr, idstr) && 1308 (instance_id == se->instance_id || 1309 instance_id == se->alias_id)) 1310 return se; 1311 /* Migrating from an older version? */ 1312 if (strstr(se->idstr, idstr) && se->compat) { 1313 if (!strcmp(se->compat->idstr, idstr) && 1314 (instance_id == se->compat->instance_id || 1315 instance_id == se->alias_id)) 1316 return se; 1317 } 1318 } 1319 return NULL; 1320 } 1321 1322 enum LoadVMExitCodes { 1323 /* Allow a command to quit all layers of nested loadvm loops */ 1324 LOADVM_QUIT = 1, 1325 }; 1326 1327 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis); 1328 1329 /* ------ incoming postcopy messages ------ */ 1330 /* 'advise' arrives before any transfers just to tell us that a postcopy 1331 * *might* happen - it might be skipped if precopy transferred everything 1332 * quickly. 1333 */ 1334 static int loadvm_postcopy_handle_advise(MigrationIncomingState *mis) 1335 { 1336 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1337 uint64_t remote_hps, remote_tps; 1338 1339 trace_loadvm_postcopy_handle_advise(); 1340 if (ps != POSTCOPY_INCOMING_NONE) { 1341 error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps); 1342 return -1; 1343 } 1344 1345 if (!postcopy_ram_supported_by_host()) { 1346 return -1; 1347 } 1348 1349 remote_hps = qemu_get_be64(mis->from_src_file); 1350 if (remote_hps != getpagesize()) { 1351 /* 1352 * Some combinations of mismatch are probably possible but it gets 1353 * a bit more complicated. In particular we need to place whole 1354 * host pages on the dest at once, and we need to ensure that we 1355 * handle dirtying to make sure we never end up sending part of 1356 * a hostpage on it's own. 1357 */ 1358 error_report("Postcopy needs matching host page sizes (s=%d d=%d)", 1359 (int)remote_hps, getpagesize()); 1360 return -1; 1361 } 1362 1363 remote_tps = qemu_get_be64(mis->from_src_file); 1364 if (remote_tps != (1ul << qemu_target_page_bits())) { 1365 /* 1366 * Again, some differences could be dealt with, but for now keep it 1367 * simple. 1368 */ 1369 error_report("Postcopy needs matching target page sizes (s=%d d=%d)", 1370 (int)remote_tps, 1 << qemu_target_page_bits()); 1371 return -1; 1372 } 1373 1374 if (ram_postcopy_incoming_init(mis)) { 1375 return -1; 1376 } 1377 1378 postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1379 1380 return 0; 1381 } 1382 1383 /* After postcopy we will be told to throw some pages away since they're 1384 * dirty and will have to be demand fetched. Must happen before CPU is 1385 * started. 1386 * There can be 0..many of these messages, each encoding multiple pages. 1387 */ 1388 static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState *mis, 1389 uint16_t len) 1390 { 1391 int tmp; 1392 char ramid[256]; 1393 PostcopyState ps = postcopy_state_get(); 1394 1395 trace_loadvm_postcopy_ram_handle_discard(); 1396 1397 switch (ps) { 1398 case POSTCOPY_INCOMING_ADVISE: 1399 /* 1st discard */ 1400 tmp = postcopy_ram_prepare_discard(mis); 1401 if (tmp) { 1402 return tmp; 1403 } 1404 break; 1405 1406 case POSTCOPY_INCOMING_DISCARD: 1407 /* Expected state */ 1408 break; 1409 1410 default: 1411 error_report("CMD_POSTCOPY_RAM_DISCARD in wrong postcopy state (%d)", 1412 ps); 1413 return -1; 1414 } 1415 /* We're expecting a 1416 * Version (0) 1417 * a RAM ID string (length byte, name, 0 term) 1418 * then at least 1 16 byte chunk 1419 */ 1420 if (len < (1 + 1 + 1 + 1 + 2 * 8)) { 1421 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1422 return -1; 1423 } 1424 1425 tmp = qemu_get_byte(mis->from_src_file); 1426 if (tmp != postcopy_ram_discard_version) { 1427 error_report("CMD_POSTCOPY_RAM_DISCARD invalid version (%d)", tmp); 1428 return -1; 1429 } 1430 1431 if (!qemu_get_counted_string(mis->from_src_file, ramid)) { 1432 error_report("CMD_POSTCOPY_RAM_DISCARD Failed to read RAMBlock ID"); 1433 return -1; 1434 } 1435 tmp = qemu_get_byte(mis->from_src_file); 1436 if (tmp != 0) { 1437 error_report("CMD_POSTCOPY_RAM_DISCARD missing nil (%d)", tmp); 1438 return -1; 1439 } 1440 1441 len -= 3 + strlen(ramid); 1442 if (len % 16) { 1443 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1444 return -1; 1445 } 1446 trace_loadvm_postcopy_ram_handle_discard_header(ramid, len); 1447 while (len) { 1448 uint64_t start_addr, block_length; 1449 start_addr = qemu_get_be64(mis->from_src_file); 1450 block_length = qemu_get_be64(mis->from_src_file); 1451 1452 len -= 16; 1453 int ret = ram_discard_range(mis, ramid, start_addr, 1454 block_length); 1455 if (ret) { 1456 return ret; 1457 } 1458 } 1459 trace_loadvm_postcopy_ram_handle_discard_end(); 1460 1461 return 0; 1462 } 1463 1464 /* 1465 * Triggered by a postcopy_listen command; this thread takes over reading 1466 * the input stream, leaving the main thread free to carry on loading the rest 1467 * of the device state (from RAM). 1468 * (TODO:This could do with being in a postcopy file - but there again it's 1469 * just another input loop, not that postcopy specific) 1470 */ 1471 static void *postcopy_ram_listen_thread(void *opaque) 1472 { 1473 QEMUFile *f = opaque; 1474 MigrationIncomingState *mis = migration_incoming_get_current(); 1475 int load_res; 1476 1477 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, 1478 MIGRATION_STATUS_POSTCOPY_ACTIVE); 1479 qemu_sem_post(&mis->listen_thread_sem); 1480 trace_postcopy_ram_listen_thread_start(); 1481 1482 /* 1483 * Because we're a thread and not a coroutine we can't yield 1484 * in qemu_file, and thus we must be blocking now. 1485 */ 1486 qemu_file_set_blocking(f, true); 1487 load_res = qemu_loadvm_state_main(f, mis); 1488 /* And non-blocking again so we don't block in any cleanup */ 1489 qemu_file_set_blocking(f, false); 1490 1491 trace_postcopy_ram_listen_thread_exit(); 1492 if (load_res < 0) { 1493 error_report("%s: loadvm failed: %d", __func__, load_res); 1494 qemu_file_set_error(f, load_res); 1495 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1496 MIGRATION_STATUS_FAILED); 1497 } else { 1498 /* 1499 * This looks good, but it's possible that the device loading in the 1500 * main thread hasn't finished yet, and so we might not be in 'RUN' 1501 * state yet; wait for the end of the main thread. 1502 */ 1503 qemu_event_wait(&mis->main_thread_load_event); 1504 } 1505 postcopy_ram_incoming_cleanup(mis); 1506 1507 if (load_res < 0) { 1508 /* 1509 * If something went wrong then we have a bad state so exit; 1510 * depending how far we got it might be possible at this point 1511 * to leave the guest running and fire MCEs for pages that never 1512 * arrived as a desperate recovery step. 1513 */ 1514 exit(EXIT_FAILURE); 1515 } 1516 1517 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1518 MIGRATION_STATUS_COMPLETED); 1519 /* 1520 * If everything has worked fine, then the main thread has waited 1521 * for us to start, and we're the last use of the mis. 1522 * (If something broke then qemu will have to exit anyway since it's 1523 * got a bad migration state). 1524 */ 1525 migration_incoming_state_destroy(); 1526 1527 1528 return NULL; 1529 } 1530 1531 /* After this message we must be able to immediately receive postcopy data */ 1532 static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) 1533 { 1534 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING); 1535 trace_loadvm_postcopy_handle_listen(); 1536 if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) { 1537 error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps); 1538 return -1; 1539 } 1540 if (ps == POSTCOPY_INCOMING_ADVISE) { 1541 /* 1542 * A rare case, we entered listen without having to do any discards, 1543 * so do the setup that's normally done at the time of the 1st discard. 1544 */ 1545 postcopy_ram_prepare_discard(mis); 1546 } 1547 1548 /* 1549 * Sensitise RAM - can now generate requests for blocks that don't exist 1550 * However, at this point the CPU shouldn't be running, and the IO 1551 * shouldn't be doing anything yet so don't actually expect requests 1552 */ 1553 if (postcopy_ram_enable_notify(mis)) { 1554 return -1; 1555 } 1556 1557 if (mis->have_listen_thread) { 1558 error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread"); 1559 return -1; 1560 } 1561 1562 mis->have_listen_thread = true; 1563 /* Start up the listening thread and wait for it to signal ready */ 1564 qemu_sem_init(&mis->listen_thread_sem, 0); 1565 qemu_thread_create(&mis->listen_thread, "postcopy/listen", 1566 postcopy_ram_listen_thread, mis->from_src_file, 1567 QEMU_THREAD_DETACHED); 1568 qemu_sem_wait(&mis->listen_thread_sem); 1569 qemu_sem_destroy(&mis->listen_thread_sem); 1570 1571 return 0; 1572 } 1573 1574 1575 typedef struct { 1576 QEMUBH *bh; 1577 } HandleRunBhData; 1578 1579 static void loadvm_postcopy_handle_run_bh(void *opaque) 1580 { 1581 Error *local_err = NULL; 1582 HandleRunBhData *data = opaque; 1583 1584 /* TODO we should move all of this lot into postcopy_ram.c or a shared code 1585 * in migration.c 1586 */ 1587 cpu_synchronize_all_post_init(); 1588 1589 qemu_announce_self(); 1590 1591 /* Make sure all file formats flush their mutable metadata */ 1592 bdrv_invalidate_cache_all(&local_err); 1593 if (local_err) { 1594 error_report_err(local_err); 1595 } 1596 1597 trace_loadvm_postcopy_handle_run_cpu_sync(); 1598 cpu_synchronize_all_post_init(); 1599 1600 trace_loadvm_postcopy_handle_run_vmstart(); 1601 1602 if (autostart) { 1603 /* Hold onto your hats, starting the CPU */ 1604 vm_start(); 1605 } else { 1606 /* leave it paused and let management decide when to start the CPU */ 1607 runstate_set(RUN_STATE_PAUSED); 1608 } 1609 1610 qemu_bh_delete(data->bh); 1611 g_free(data); 1612 } 1613 1614 /* After all discards we can start running and asking for pages */ 1615 static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) 1616 { 1617 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_RUNNING); 1618 HandleRunBhData *data; 1619 1620 trace_loadvm_postcopy_handle_run(); 1621 if (ps != POSTCOPY_INCOMING_LISTENING) { 1622 error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps); 1623 return -1; 1624 } 1625 1626 data = g_new(HandleRunBhData, 1); 1627 data->bh = qemu_bh_new(loadvm_postcopy_handle_run_bh, data); 1628 qemu_bh_schedule(data->bh); 1629 1630 /* We need to finish reading the stream from the package 1631 * and also stop reading anything more from the stream that loaded the 1632 * package (since it's now being read by the listener thread). 1633 * LOADVM_QUIT will quit all the layers of nested loadvm loops. 1634 */ 1635 return LOADVM_QUIT; 1636 } 1637 1638 /** 1639 * Immediately following this command is a blob of data containing an embedded 1640 * chunk of migration stream; read it and load it. 1641 * 1642 * @mis: Incoming state 1643 * @length: Length of packaged data to read 1644 * 1645 * Returns: Negative values on error 1646 * 1647 */ 1648 static int loadvm_handle_cmd_packaged(MigrationIncomingState *mis) 1649 { 1650 int ret; 1651 size_t length; 1652 QIOChannelBuffer *bioc; 1653 1654 length = qemu_get_be32(mis->from_src_file); 1655 trace_loadvm_handle_cmd_packaged(length); 1656 1657 if (length > MAX_VM_CMD_PACKAGED_SIZE) { 1658 error_report("Unreasonably large packaged state: %zu", length); 1659 return -1; 1660 } 1661 1662 bioc = qio_channel_buffer_new(length); 1663 qio_channel_set_name(QIO_CHANNEL(bioc), "migration-loadvm-buffer"); 1664 ret = qemu_get_buffer(mis->from_src_file, 1665 bioc->data, 1666 length); 1667 if (ret != length) { 1668 object_unref(OBJECT(bioc)); 1669 error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%zu", 1670 ret, length); 1671 return (ret < 0) ? ret : -EAGAIN; 1672 } 1673 bioc->usage += length; 1674 trace_loadvm_handle_cmd_packaged_received(ret); 1675 1676 QEMUFile *packf = qemu_fopen_channel_input(QIO_CHANNEL(bioc)); 1677 1678 ret = qemu_loadvm_state_main(packf, mis); 1679 trace_loadvm_handle_cmd_packaged_main(ret); 1680 qemu_fclose(packf); 1681 object_unref(OBJECT(bioc)); 1682 1683 return ret; 1684 } 1685 1686 /* 1687 * Process an incoming 'QEMU_VM_COMMAND' 1688 * 0 just a normal return 1689 * LOADVM_QUIT All good, but exit the loop 1690 * <0 Error 1691 */ 1692 static int loadvm_process_command(QEMUFile *f) 1693 { 1694 MigrationIncomingState *mis = migration_incoming_get_current(); 1695 uint16_t cmd; 1696 uint16_t len; 1697 uint32_t tmp32; 1698 1699 cmd = qemu_get_be16(f); 1700 len = qemu_get_be16(f); 1701 1702 trace_loadvm_process_command(cmd, len); 1703 if (cmd >= MIG_CMD_MAX || cmd == MIG_CMD_INVALID) { 1704 error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd, len); 1705 return -EINVAL; 1706 } 1707 1708 if (mig_cmd_args[cmd].len != -1 && mig_cmd_args[cmd].len != len) { 1709 error_report("%s received with bad length - expecting %zu, got %d", 1710 mig_cmd_args[cmd].name, 1711 (size_t)mig_cmd_args[cmd].len, len); 1712 return -ERANGE; 1713 } 1714 1715 switch (cmd) { 1716 case MIG_CMD_OPEN_RETURN_PATH: 1717 if (mis->to_src_file) { 1718 error_report("CMD_OPEN_RETURN_PATH called when RP already open"); 1719 /* Not really a problem, so don't give up */ 1720 return 0; 1721 } 1722 mis->to_src_file = qemu_file_get_return_path(f); 1723 if (!mis->to_src_file) { 1724 error_report("CMD_OPEN_RETURN_PATH failed"); 1725 return -1; 1726 } 1727 break; 1728 1729 case MIG_CMD_PING: 1730 tmp32 = qemu_get_be32(f); 1731 trace_loadvm_process_command_ping(tmp32); 1732 if (!mis->to_src_file) { 1733 error_report("CMD_PING (0x%x) received with no return path", 1734 tmp32); 1735 return -1; 1736 } 1737 migrate_send_rp_pong(mis, tmp32); 1738 break; 1739 1740 case MIG_CMD_PACKAGED: 1741 return loadvm_handle_cmd_packaged(mis); 1742 1743 case MIG_CMD_POSTCOPY_ADVISE: 1744 return loadvm_postcopy_handle_advise(mis); 1745 1746 case MIG_CMD_POSTCOPY_LISTEN: 1747 return loadvm_postcopy_handle_listen(mis); 1748 1749 case MIG_CMD_POSTCOPY_RUN: 1750 return loadvm_postcopy_handle_run(mis); 1751 1752 case MIG_CMD_POSTCOPY_RAM_DISCARD: 1753 return loadvm_postcopy_ram_handle_discard(mis, len); 1754 } 1755 1756 return 0; 1757 } 1758 1759 struct LoadStateEntry { 1760 QLIST_ENTRY(LoadStateEntry) entry; 1761 SaveStateEntry *se; 1762 int section_id; 1763 int version_id; 1764 }; 1765 1766 /* 1767 * Read a footer off the wire and check that it matches the expected section 1768 * 1769 * Returns: true if the footer was good 1770 * false if there is a problem (and calls error_report to say why) 1771 */ 1772 static bool check_section_footer(QEMUFile *f, LoadStateEntry *le) 1773 { 1774 uint8_t read_mark; 1775 uint32_t read_section_id; 1776 1777 if (skip_section_footers) { 1778 /* No footer to check */ 1779 return true; 1780 } 1781 1782 read_mark = qemu_get_byte(f); 1783 1784 if (read_mark != QEMU_VM_SECTION_FOOTER) { 1785 error_report("Missing section footer for %s", le->se->idstr); 1786 return false; 1787 } 1788 1789 read_section_id = qemu_get_be32(f); 1790 if (read_section_id != le->section_id) { 1791 error_report("Mismatched section id in footer for %s -" 1792 " read 0x%x expected 0x%x", 1793 le->se->idstr, read_section_id, le->section_id); 1794 return false; 1795 } 1796 1797 /* All good */ 1798 return true; 1799 } 1800 1801 void loadvm_free_handlers(MigrationIncomingState *mis) 1802 { 1803 LoadStateEntry *le, *new_le; 1804 1805 QLIST_FOREACH_SAFE(le, &mis->loadvm_handlers, entry, new_le) { 1806 QLIST_REMOVE(le, entry); 1807 g_free(le); 1808 } 1809 } 1810 1811 static int 1812 qemu_loadvm_section_start_full(QEMUFile *f, MigrationIncomingState *mis) 1813 { 1814 uint32_t instance_id, version_id, section_id; 1815 SaveStateEntry *se; 1816 LoadStateEntry *le; 1817 char idstr[256]; 1818 int ret; 1819 1820 /* Read section start */ 1821 section_id = qemu_get_be32(f); 1822 if (!qemu_get_counted_string(f, idstr)) { 1823 error_report("Unable to read ID string for section %u", 1824 section_id); 1825 return -EINVAL; 1826 } 1827 instance_id = qemu_get_be32(f); 1828 version_id = qemu_get_be32(f); 1829 1830 trace_qemu_loadvm_state_section_startfull(section_id, idstr, 1831 instance_id, version_id); 1832 /* Find savevm section */ 1833 se = find_se(idstr, instance_id); 1834 if (se == NULL) { 1835 error_report("Unknown savevm section or instance '%s' %d", 1836 idstr, instance_id); 1837 return -EINVAL; 1838 } 1839 1840 /* Validate version */ 1841 if (version_id > se->version_id) { 1842 error_report("savevm: unsupported version %d for '%s' v%d", 1843 version_id, idstr, se->version_id); 1844 return -EINVAL; 1845 } 1846 1847 /* Validate if it is a device's state */ 1848 if (xen_enabled() && se->is_ram) { 1849 error_report("loadvm: %s RAM loading not allowed on Xen", idstr); 1850 return -EINVAL; 1851 } 1852 1853 /* Add entry */ 1854 le = g_malloc0(sizeof(*le)); 1855 1856 le->se = se; 1857 le->section_id = section_id; 1858 le->version_id = version_id; 1859 QLIST_INSERT_HEAD(&mis->loadvm_handlers, le, entry); 1860 1861 ret = vmstate_load(f, le->se, le->version_id); 1862 if (ret < 0) { 1863 error_report("error while loading state for instance 0x%x of" 1864 " device '%s'", instance_id, idstr); 1865 return ret; 1866 } 1867 if (!check_section_footer(f, le)) { 1868 return -EINVAL; 1869 } 1870 1871 return 0; 1872 } 1873 1874 static int 1875 qemu_loadvm_section_part_end(QEMUFile *f, MigrationIncomingState *mis) 1876 { 1877 uint32_t section_id; 1878 LoadStateEntry *le; 1879 int ret; 1880 1881 section_id = qemu_get_be32(f); 1882 1883 trace_qemu_loadvm_state_section_partend(section_id); 1884 QLIST_FOREACH(le, &mis->loadvm_handlers, entry) { 1885 if (le->section_id == section_id) { 1886 break; 1887 } 1888 } 1889 if (le == NULL) { 1890 error_report("Unknown savevm section %d", section_id); 1891 return -EINVAL; 1892 } 1893 1894 ret = vmstate_load(f, le->se, le->version_id); 1895 if (ret < 0) { 1896 error_report("error while loading state section id %d(%s)", 1897 section_id, le->se->idstr); 1898 return ret; 1899 } 1900 if (!check_section_footer(f, le)) { 1901 return -EINVAL; 1902 } 1903 1904 return 0; 1905 } 1906 1907 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis) 1908 { 1909 uint8_t section_type; 1910 int ret = 0; 1911 1912 while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) { 1913 ret = 0; 1914 trace_qemu_loadvm_state_section(section_type); 1915 switch (section_type) { 1916 case QEMU_VM_SECTION_START: 1917 case QEMU_VM_SECTION_FULL: 1918 ret = qemu_loadvm_section_start_full(f, mis); 1919 if (ret < 0) { 1920 goto out; 1921 } 1922 break; 1923 case QEMU_VM_SECTION_PART: 1924 case QEMU_VM_SECTION_END: 1925 ret = qemu_loadvm_section_part_end(f, mis); 1926 if (ret < 0) { 1927 goto out; 1928 } 1929 break; 1930 case QEMU_VM_COMMAND: 1931 ret = loadvm_process_command(f); 1932 trace_qemu_loadvm_state_section_command(ret); 1933 if ((ret < 0) || (ret & LOADVM_QUIT)) { 1934 goto out; 1935 } 1936 break; 1937 default: 1938 error_report("Unknown savevm section type %d", section_type); 1939 ret = -EINVAL; 1940 goto out; 1941 } 1942 } 1943 1944 out: 1945 if (ret < 0) { 1946 qemu_file_set_error(f, ret); 1947 } 1948 return ret; 1949 } 1950 1951 int qemu_loadvm_state(QEMUFile *f) 1952 { 1953 MigrationIncomingState *mis = migration_incoming_get_current(); 1954 Error *local_err = NULL; 1955 unsigned int v; 1956 int ret; 1957 1958 if (qemu_savevm_state_blocked(&local_err)) { 1959 error_report_err(local_err); 1960 return -EINVAL; 1961 } 1962 1963 v = qemu_get_be32(f); 1964 if (v != QEMU_VM_FILE_MAGIC) { 1965 error_report("Not a migration stream"); 1966 return -EINVAL; 1967 } 1968 1969 v = qemu_get_be32(f); 1970 if (v == QEMU_VM_FILE_VERSION_COMPAT) { 1971 error_report("SaveVM v2 format is obsolete and don't work anymore"); 1972 return -ENOTSUP; 1973 } 1974 if (v != QEMU_VM_FILE_VERSION) { 1975 error_report("Unsupported migration stream version"); 1976 return -ENOTSUP; 1977 } 1978 1979 if (!savevm_state.skip_configuration || enforce_config_section()) { 1980 if (qemu_get_byte(f) != QEMU_VM_CONFIGURATION) { 1981 error_report("Configuration section missing"); 1982 return -EINVAL; 1983 } 1984 ret = vmstate_load_state(f, &vmstate_configuration, &savevm_state, 0); 1985 1986 if (ret) { 1987 return ret; 1988 } 1989 } 1990 1991 ret = qemu_loadvm_state_main(f, mis); 1992 qemu_event_set(&mis->main_thread_load_event); 1993 1994 trace_qemu_loadvm_state_post_main(ret); 1995 1996 if (mis->have_listen_thread) { 1997 /* Listen thread still going, can't clean up yet */ 1998 return ret; 1999 } 2000 2001 if (ret == 0) { 2002 ret = qemu_file_get_error(f); 2003 } 2004 2005 /* 2006 * Try to read in the VMDESC section as well, so that dumping tools that 2007 * intercept our migration stream have the chance to see it. 2008 */ 2009 2010 /* We've got to be careful; if we don't read the data and just shut the fd 2011 * then the sender can error if we close while it's still sending. 2012 * We also mustn't read data that isn't there; some transports (RDMA) 2013 * will stall waiting for that data when the source has already closed. 2014 */ 2015 if (ret == 0 && should_send_vmdesc()) { 2016 uint8_t *buf; 2017 uint32_t size; 2018 uint8_t section_type = qemu_get_byte(f); 2019 2020 if (section_type != QEMU_VM_VMDESCRIPTION) { 2021 error_report("Expected vmdescription section, but got %d", 2022 section_type); 2023 /* 2024 * It doesn't seem worth failing at this point since 2025 * we apparently have an otherwise valid VM state 2026 */ 2027 } else { 2028 buf = g_malloc(0x1000); 2029 size = qemu_get_be32(f); 2030 2031 while (size > 0) { 2032 uint32_t read_chunk = MIN(size, 0x1000); 2033 qemu_get_buffer(f, buf, read_chunk); 2034 size -= read_chunk; 2035 } 2036 g_free(buf); 2037 } 2038 } 2039 2040 cpu_synchronize_all_post_init(); 2041 2042 return ret; 2043 } 2044 2045 void hmp_savevm(Monitor *mon, const QDict *qdict) 2046 { 2047 BlockDriverState *bs, *bs1; 2048 QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1; 2049 int ret; 2050 QEMUFile *f; 2051 int saved_vm_running; 2052 uint64_t vm_state_size; 2053 qemu_timeval tv; 2054 struct tm tm; 2055 const char *name = qdict_get_try_str(qdict, "name"); 2056 Error *local_err = NULL; 2057 AioContext *aio_context; 2058 2059 if (!bdrv_all_can_snapshot(&bs)) { 2060 monitor_printf(mon, "Device '%s' is writable but does not " 2061 "support snapshots.\n", bdrv_get_device_name(bs)); 2062 return; 2063 } 2064 2065 /* Delete old snapshots of the same name */ 2066 if (name && bdrv_all_delete_snapshot(name, &bs1, &local_err) < 0) { 2067 error_reportf_err(local_err, 2068 "Error while deleting snapshot on device '%s': ", 2069 bdrv_get_device_name(bs1)); 2070 return; 2071 } 2072 2073 bs = bdrv_all_find_vmstate_bs(); 2074 if (bs == NULL) { 2075 monitor_printf(mon, "No block device can accept snapshots\n"); 2076 return; 2077 } 2078 aio_context = bdrv_get_aio_context(bs); 2079 2080 saved_vm_running = runstate_is_running(); 2081 2082 ret = global_state_store(); 2083 if (ret) { 2084 monitor_printf(mon, "Error saving global state\n"); 2085 return; 2086 } 2087 vm_stop(RUN_STATE_SAVE_VM); 2088 2089 aio_context_acquire(aio_context); 2090 2091 memset(sn, 0, sizeof(*sn)); 2092 2093 /* fill auxiliary fields */ 2094 qemu_gettimeofday(&tv); 2095 sn->date_sec = tv.tv_sec; 2096 sn->date_nsec = tv.tv_usec * 1000; 2097 sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 2098 2099 if (name) { 2100 ret = bdrv_snapshot_find(bs, old_sn, name); 2101 if (ret >= 0) { 2102 pstrcpy(sn->name, sizeof(sn->name), old_sn->name); 2103 pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str); 2104 } else { 2105 pstrcpy(sn->name, sizeof(sn->name), name); 2106 } 2107 } else { 2108 /* cast below needed for OpenBSD where tv_sec is still 'long' */ 2109 localtime_r((const time_t *)&tv.tv_sec, &tm); 2110 strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm); 2111 } 2112 2113 /* save the VM state */ 2114 f = qemu_fopen_bdrv(bs, 1); 2115 if (!f) { 2116 monitor_printf(mon, "Could not open VM state file\n"); 2117 goto the_end; 2118 } 2119 ret = qemu_savevm_state(f, &local_err); 2120 vm_state_size = qemu_ftell(f); 2121 qemu_fclose(f); 2122 if (ret < 0) { 2123 error_report_err(local_err); 2124 goto the_end; 2125 } 2126 2127 ret = bdrv_all_create_snapshot(sn, bs, vm_state_size, &bs); 2128 if (ret < 0) { 2129 monitor_printf(mon, "Error while creating snapshot on '%s'\n", 2130 bdrv_get_device_name(bs)); 2131 } 2132 2133 the_end: 2134 aio_context_release(aio_context); 2135 if (saved_vm_running) { 2136 vm_start(); 2137 } 2138 } 2139 2140 void qmp_xen_save_devices_state(const char *filename, Error **errp) 2141 { 2142 QEMUFile *f; 2143 QIOChannelFile *ioc; 2144 int saved_vm_running; 2145 int ret; 2146 2147 saved_vm_running = runstate_is_running(); 2148 vm_stop(RUN_STATE_SAVE_VM); 2149 global_state_store_running(); 2150 2151 ioc = qio_channel_file_new_path(filename, O_WRONLY | O_CREAT, 0660, errp); 2152 if (!ioc) { 2153 goto the_end; 2154 } 2155 qio_channel_set_name(QIO_CHANNEL(ioc), "migration-xen-save-state"); 2156 f = qemu_fopen_channel_output(QIO_CHANNEL(ioc)); 2157 ret = qemu_save_device_state(f); 2158 qemu_fclose(f); 2159 if (ret < 0) { 2160 error_setg(errp, QERR_IO_ERROR); 2161 } 2162 2163 the_end: 2164 if (saved_vm_running) { 2165 vm_start(); 2166 } 2167 } 2168 2169 void qmp_xen_load_devices_state(const char *filename, Error **errp) 2170 { 2171 QEMUFile *f; 2172 QIOChannelFile *ioc; 2173 int ret; 2174 2175 /* Guest must be paused before loading the device state; the RAM state 2176 * will already have been loaded by xc 2177 */ 2178 if (runstate_is_running()) { 2179 error_setg(errp, "Cannot update device state while vm is running"); 2180 return; 2181 } 2182 vm_stop(RUN_STATE_RESTORE_VM); 2183 2184 ioc = qio_channel_file_new_path(filename, O_RDONLY | O_BINARY, 0, errp); 2185 if (!ioc) { 2186 return; 2187 } 2188 qio_channel_set_name(QIO_CHANNEL(ioc), "migration-xen-load-state"); 2189 f = qemu_fopen_channel_input(QIO_CHANNEL(ioc)); 2190 2191 migration_incoming_state_new(f); 2192 ret = qemu_loadvm_state(f); 2193 qemu_fclose(f); 2194 if (ret < 0) { 2195 error_setg(errp, QERR_IO_ERROR); 2196 } 2197 migration_incoming_state_destroy(); 2198 } 2199 2200 int load_vmstate(const char *name) 2201 { 2202 BlockDriverState *bs, *bs_vm_state; 2203 QEMUSnapshotInfo sn; 2204 QEMUFile *f; 2205 int ret; 2206 AioContext *aio_context; 2207 2208 if (!bdrv_all_can_snapshot(&bs)) { 2209 error_report("Device '%s' is writable but does not support snapshots.", 2210 bdrv_get_device_name(bs)); 2211 return -ENOTSUP; 2212 } 2213 ret = bdrv_all_find_snapshot(name, &bs); 2214 if (ret < 0) { 2215 error_report("Device '%s' does not have the requested snapshot '%s'", 2216 bdrv_get_device_name(bs), name); 2217 return ret; 2218 } 2219 2220 bs_vm_state = bdrv_all_find_vmstate_bs(); 2221 if (!bs_vm_state) { 2222 error_report("No block device supports snapshots"); 2223 return -ENOTSUP; 2224 } 2225 aio_context = bdrv_get_aio_context(bs_vm_state); 2226 2227 /* Don't even try to load empty VM states */ 2228 aio_context_acquire(aio_context); 2229 ret = bdrv_snapshot_find(bs_vm_state, &sn, name); 2230 aio_context_release(aio_context); 2231 if (ret < 0) { 2232 return ret; 2233 } else if (sn.vm_state_size == 0) { 2234 error_report("This is a disk-only snapshot. Revert to it offline " 2235 "using qemu-img."); 2236 return -EINVAL; 2237 } 2238 2239 /* Flush all IO requests so they don't interfere with the new state. */ 2240 bdrv_drain_all(); 2241 2242 ret = bdrv_all_goto_snapshot(name, &bs); 2243 if (ret < 0) { 2244 error_report("Error %d while activating snapshot '%s' on '%s'", 2245 ret, name, bdrv_get_device_name(bs)); 2246 return ret; 2247 } 2248 2249 /* restore the VM state */ 2250 f = qemu_fopen_bdrv(bs_vm_state, 0); 2251 if (!f) { 2252 error_report("Could not open VM state file"); 2253 return -EINVAL; 2254 } 2255 2256 qemu_system_reset(VMRESET_SILENT); 2257 migration_incoming_state_new(f); 2258 2259 aio_context_acquire(aio_context); 2260 ret = qemu_loadvm_state(f); 2261 qemu_fclose(f); 2262 aio_context_release(aio_context); 2263 2264 migration_incoming_state_destroy(); 2265 if (ret < 0) { 2266 error_report("Error %d while loading VM state", ret); 2267 return ret; 2268 } 2269 2270 return 0; 2271 } 2272 2273 void hmp_delvm(Monitor *mon, const QDict *qdict) 2274 { 2275 BlockDriverState *bs; 2276 Error *err; 2277 const char *name = qdict_get_str(qdict, "name"); 2278 2279 if (bdrv_all_delete_snapshot(name, &bs, &err) < 0) { 2280 error_reportf_err(err, 2281 "Error while deleting snapshot on device '%s': ", 2282 bdrv_get_device_name(bs)); 2283 } 2284 } 2285 2286 void hmp_info_snapshots(Monitor *mon, const QDict *qdict) 2287 { 2288 BlockDriverState *bs, *bs1; 2289 BdrvNextIterator it1; 2290 QEMUSnapshotInfo *sn_tab, *sn; 2291 bool no_snapshot = true; 2292 int nb_sns, i; 2293 int total; 2294 int *global_snapshots; 2295 AioContext *aio_context; 2296 2297 typedef struct SnapshotEntry { 2298 QEMUSnapshotInfo sn; 2299 QTAILQ_ENTRY(SnapshotEntry) next; 2300 } SnapshotEntry; 2301 2302 typedef struct ImageEntry { 2303 const char *imagename; 2304 QTAILQ_ENTRY(ImageEntry) next; 2305 QTAILQ_HEAD(, SnapshotEntry) snapshots; 2306 } ImageEntry; 2307 2308 QTAILQ_HEAD(, ImageEntry) image_list = 2309 QTAILQ_HEAD_INITIALIZER(image_list); 2310 2311 ImageEntry *image_entry, *next_ie; 2312 SnapshotEntry *snapshot_entry; 2313 2314 bs = bdrv_all_find_vmstate_bs(); 2315 if (!bs) { 2316 monitor_printf(mon, "No available block device supports snapshots\n"); 2317 return; 2318 } 2319 aio_context = bdrv_get_aio_context(bs); 2320 2321 aio_context_acquire(aio_context); 2322 nb_sns = bdrv_snapshot_list(bs, &sn_tab); 2323 aio_context_release(aio_context); 2324 2325 if (nb_sns < 0) { 2326 monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns); 2327 return; 2328 } 2329 2330 for (bs1 = bdrv_first(&it1); bs1; bs1 = bdrv_next(&it1)) { 2331 int bs1_nb_sns = 0; 2332 ImageEntry *ie; 2333 SnapshotEntry *se; 2334 AioContext *ctx = bdrv_get_aio_context(bs1); 2335 2336 aio_context_acquire(ctx); 2337 if (bdrv_can_snapshot(bs1)) { 2338 sn = NULL; 2339 bs1_nb_sns = bdrv_snapshot_list(bs1, &sn); 2340 if (bs1_nb_sns > 0) { 2341 no_snapshot = false; 2342 ie = g_new0(ImageEntry, 1); 2343 ie->imagename = bdrv_get_device_name(bs1); 2344 QTAILQ_INIT(&ie->snapshots); 2345 QTAILQ_INSERT_TAIL(&image_list, ie, next); 2346 for (i = 0; i < bs1_nb_sns; i++) { 2347 se = g_new0(SnapshotEntry, 1); 2348 se->sn = sn[i]; 2349 QTAILQ_INSERT_TAIL(&ie->snapshots, se, next); 2350 } 2351 } 2352 g_free(sn); 2353 } 2354 aio_context_release(ctx); 2355 } 2356 2357 if (no_snapshot) { 2358 monitor_printf(mon, "There is no snapshot available.\n"); 2359 return; 2360 } 2361 2362 global_snapshots = g_new0(int, nb_sns); 2363 total = 0; 2364 for (i = 0; i < nb_sns; i++) { 2365 SnapshotEntry *next_sn; 2366 if (bdrv_all_find_snapshot(sn_tab[i].name, &bs1) == 0) { 2367 global_snapshots[total] = i; 2368 total++; 2369 QTAILQ_FOREACH(image_entry, &image_list, next) { 2370 QTAILQ_FOREACH_SAFE(snapshot_entry, &image_entry->snapshots, 2371 next, next_sn) { 2372 if (!strcmp(sn_tab[i].name, snapshot_entry->sn.name)) { 2373 QTAILQ_REMOVE(&image_entry->snapshots, snapshot_entry, 2374 next); 2375 g_free(snapshot_entry); 2376 } 2377 } 2378 } 2379 } 2380 } 2381 2382 monitor_printf(mon, "List of snapshots present on all disks:\n"); 2383 2384 if (total > 0) { 2385 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL); 2386 monitor_printf(mon, "\n"); 2387 for (i = 0; i < total; i++) { 2388 sn = &sn_tab[global_snapshots[i]]; 2389 /* The ID is not guaranteed to be the same on all images, so 2390 * overwrite it. 2391 */ 2392 pstrcpy(sn->id_str, sizeof(sn->id_str), "--"); 2393 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn); 2394 monitor_printf(mon, "\n"); 2395 } 2396 } else { 2397 monitor_printf(mon, "None\n"); 2398 } 2399 2400 QTAILQ_FOREACH(image_entry, &image_list, next) { 2401 if (QTAILQ_EMPTY(&image_entry->snapshots)) { 2402 continue; 2403 } 2404 monitor_printf(mon, 2405 "\nList of partial (non-loadable) snapshots on '%s':\n", 2406 image_entry->imagename); 2407 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL); 2408 monitor_printf(mon, "\n"); 2409 QTAILQ_FOREACH(snapshot_entry, &image_entry->snapshots, next) { 2410 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, 2411 &snapshot_entry->sn); 2412 monitor_printf(mon, "\n"); 2413 } 2414 } 2415 2416 QTAILQ_FOREACH_SAFE(image_entry, &image_list, next, next_ie) { 2417 SnapshotEntry *next_sn; 2418 QTAILQ_FOREACH_SAFE(snapshot_entry, &image_entry->snapshots, next, 2419 next_sn) { 2420 g_free(snapshot_entry); 2421 } 2422 g_free(image_entry); 2423 } 2424 g_free(sn_tab); 2425 g_free(global_snapshots); 2426 2427 } 2428 2429 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev) 2430 { 2431 qemu_ram_set_idstr(mr->ram_block, 2432 memory_region_name(mr), dev); 2433 } 2434 2435 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev) 2436 { 2437 qemu_ram_unset_idstr(mr->ram_block); 2438 } 2439 2440 void vmstate_register_ram_global(MemoryRegion *mr) 2441 { 2442 vmstate_register_ram(mr, NULL); 2443 } 2444