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) 224 { 225 QEMUTimer *v = pv; 226 timer_get(f, v); 227 return 0; 228 } 229 230 static void put_timer(QEMUFile *f, void *pv, size_t size) 231 { 232 QEMUTimer *v = pv; 233 timer_put(f, v); 234 } 235 236 const VMStateInfo vmstate_info_timer = { 237 .name = "timer", 238 .get = get_timer, 239 .put = put_timer, 240 }; 241 242 243 typedef struct CompatEntry { 244 char idstr[256]; 245 int instance_id; 246 } CompatEntry; 247 248 typedef struct SaveStateEntry { 249 QTAILQ_ENTRY(SaveStateEntry) entry; 250 char idstr[256]; 251 int instance_id; 252 int alias_id; 253 int version_id; 254 int section_id; 255 SaveVMHandlers *ops; 256 const VMStateDescription *vmsd; 257 void *opaque; 258 CompatEntry *compat; 259 int is_ram; 260 } SaveStateEntry; 261 262 typedef struct SaveState { 263 QTAILQ_HEAD(, SaveStateEntry) handlers; 264 int global_section_id; 265 bool skip_configuration; 266 uint32_t len; 267 const char *name; 268 } SaveState; 269 270 static SaveState savevm_state = { 271 .handlers = QTAILQ_HEAD_INITIALIZER(savevm_state.handlers), 272 .global_section_id = 0, 273 .skip_configuration = false, 274 }; 275 276 void savevm_skip_configuration(void) 277 { 278 savevm_state.skip_configuration = true; 279 } 280 281 282 static void configuration_pre_save(void *opaque) 283 { 284 SaveState *state = opaque; 285 const char *current_name = MACHINE_GET_CLASS(current_machine)->name; 286 287 state->len = strlen(current_name); 288 state->name = current_name; 289 } 290 291 static int configuration_post_load(void *opaque, int version_id) 292 { 293 SaveState *state = opaque; 294 const char *current_name = MACHINE_GET_CLASS(current_machine)->name; 295 296 if (strncmp(state->name, current_name, state->len) != 0) { 297 error_report("Machine type received is '%.*s' and local is '%s'", 298 (int) state->len, state->name, current_name); 299 return -EINVAL; 300 } 301 return 0; 302 } 303 304 static const VMStateDescription vmstate_configuration = { 305 .name = "configuration", 306 .version_id = 1, 307 .post_load = configuration_post_load, 308 .pre_save = configuration_pre_save, 309 .fields = (VMStateField[]) { 310 VMSTATE_UINT32(len, SaveState), 311 VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, 0, len), 312 VMSTATE_END_OF_LIST() 313 }, 314 }; 315 316 static void dump_vmstate_vmsd(FILE *out_file, 317 const VMStateDescription *vmsd, int indent, 318 bool is_subsection); 319 320 static void dump_vmstate_vmsf(FILE *out_file, const VMStateField *field, 321 int indent) 322 { 323 fprintf(out_file, "%*s{\n", indent, ""); 324 indent += 2; 325 fprintf(out_file, "%*s\"field\": \"%s\",\n", indent, "", field->name); 326 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 327 field->version_id); 328 fprintf(out_file, "%*s\"field_exists\": %s,\n", indent, "", 329 field->field_exists ? "true" : "false"); 330 fprintf(out_file, "%*s\"size\": %zu", indent, "", field->size); 331 if (field->vmsd != NULL) { 332 fprintf(out_file, ",\n"); 333 dump_vmstate_vmsd(out_file, field->vmsd, indent, false); 334 } 335 fprintf(out_file, "\n%*s}", indent - 2, ""); 336 } 337 338 static void dump_vmstate_vmss(FILE *out_file, 339 const VMStateDescription **subsection, 340 int indent) 341 { 342 if (*subsection != NULL) { 343 dump_vmstate_vmsd(out_file, *subsection, indent, true); 344 } 345 } 346 347 static void dump_vmstate_vmsd(FILE *out_file, 348 const VMStateDescription *vmsd, int indent, 349 bool is_subsection) 350 { 351 if (is_subsection) { 352 fprintf(out_file, "%*s{\n", indent, ""); 353 } else { 354 fprintf(out_file, "%*s\"%s\": {\n", indent, "", "Description"); 355 } 356 indent += 2; 357 fprintf(out_file, "%*s\"name\": \"%s\",\n", indent, "", vmsd->name); 358 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 359 vmsd->version_id); 360 fprintf(out_file, "%*s\"minimum_version_id\": %d", indent, "", 361 vmsd->minimum_version_id); 362 if (vmsd->fields != NULL) { 363 const VMStateField *field = vmsd->fields; 364 bool first; 365 366 fprintf(out_file, ",\n%*s\"Fields\": [\n", indent, ""); 367 first = true; 368 while (field->name != NULL) { 369 if (field->flags & VMS_MUST_EXIST) { 370 /* Ignore VMSTATE_VALIDATE bits; these don't get migrated */ 371 field++; 372 continue; 373 } 374 if (!first) { 375 fprintf(out_file, ",\n"); 376 } 377 dump_vmstate_vmsf(out_file, field, indent + 2); 378 field++; 379 first = false; 380 } 381 fprintf(out_file, "\n%*s]", indent, ""); 382 } 383 if (vmsd->subsections != NULL) { 384 const VMStateDescription **subsection = vmsd->subsections; 385 bool first; 386 387 fprintf(out_file, ",\n%*s\"Subsections\": [\n", indent, ""); 388 first = true; 389 while (*subsection != NULL) { 390 if (!first) { 391 fprintf(out_file, ",\n"); 392 } 393 dump_vmstate_vmss(out_file, subsection, indent + 2); 394 subsection++; 395 first = false; 396 } 397 fprintf(out_file, "\n%*s]", indent, ""); 398 } 399 fprintf(out_file, "\n%*s}", indent - 2, ""); 400 } 401 402 static void dump_machine_type(FILE *out_file) 403 { 404 MachineClass *mc; 405 406 mc = MACHINE_GET_CLASS(current_machine); 407 408 fprintf(out_file, " \"vmschkmachine\": {\n"); 409 fprintf(out_file, " \"Name\": \"%s\"\n", mc->name); 410 fprintf(out_file, " },\n"); 411 } 412 413 void dump_vmstate_json_to_file(FILE *out_file) 414 { 415 GSList *list, *elt; 416 bool first; 417 418 fprintf(out_file, "{\n"); 419 dump_machine_type(out_file); 420 421 first = true; 422 list = object_class_get_list(TYPE_DEVICE, true); 423 for (elt = list; elt; elt = elt->next) { 424 DeviceClass *dc = OBJECT_CLASS_CHECK(DeviceClass, elt->data, 425 TYPE_DEVICE); 426 const char *name; 427 int indent = 2; 428 429 if (!dc->vmsd) { 430 continue; 431 } 432 433 if (!first) { 434 fprintf(out_file, ",\n"); 435 } 436 name = object_class_get_name(OBJECT_CLASS(dc)); 437 fprintf(out_file, "%*s\"%s\": {\n", indent, "", name); 438 indent += 2; 439 fprintf(out_file, "%*s\"Name\": \"%s\",\n", indent, "", name); 440 fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", 441 dc->vmsd->version_id); 442 fprintf(out_file, "%*s\"minimum_version_id\": %d,\n", indent, "", 443 dc->vmsd->minimum_version_id); 444 445 dump_vmstate_vmsd(out_file, dc->vmsd, indent, false); 446 447 fprintf(out_file, "\n%*s}", indent - 2, ""); 448 first = false; 449 } 450 fprintf(out_file, "\n}\n"); 451 fclose(out_file); 452 } 453 454 static int calculate_new_instance_id(const char *idstr) 455 { 456 SaveStateEntry *se; 457 int instance_id = 0; 458 459 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 460 if (strcmp(idstr, se->idstr) == 0 461 && instance_id <= se->instance_id) { 462 instance_id = se->instance_id + 1; 463 } 464 } 465 return instance_id; 466 } 467 468 static int calculate_compat_instance_id(const char *idstr) 469 { 470 SaveStateEntry *se; 471 int instance_id = 0; 472 473 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 474 if (!se->compat) { 475 continue; 476 } 477 478 if (strcmp(idstr, se->compat->idstr) == 0 479 && instance_id <= se->compat->instance_id) { 480 instance_id = se->compat->instance_id + 1; 481 } 482 } 483 return instance_id; 484 } 485 486 /* TODO: Individual devices generally have very little idea about the rest 487 of the system, so instance_id should be removed/replaced. 488 Meanwhile pass -1 as instance_id if you do not already have a clearly 489 distinguishing id for all instances of your device class. */ 490 int register_savevm_live(DeviceState *dev, 491 const char *idstr, 492 int instance_id, 493 int version_id, 494 SaveVMHandlers *ops, 495 void *opaque) 496 { 497 SaveStateEntry *se; 498 499 se = g_new0(SaveStateEntry, 1); 500 se->version_id = version_id; 501 se->section_id = savevm_state.global_section_id++; 502 se->ops = ops; 503 se->opaque = opaque; 504 se->vmsd = NULL; 505 /* if this is a live_savem then set is_ram */ 506 if (ops->save_live_setup != NULL) { 507 se->is_ram = 1; 508 } 509 510 if (dev) { 511 char *id = qdev_get_dev_path(dev); 512 if (id) { 513 pstrcpy(se->idstr, sizeof(se->idstr), id); 514 pstrcat(se->idstr, sizeof(se->idstr), "/"); 515 g_free(id); 516 517 se->compat = g_new0(CompatEntry, 1); 518 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr); 519 se->compat->instance_id = instance_id == -1 ? 520 calculate_compat_instance_id(idstr) : instance_id; 521 instance_id = -1; 522 } 523 } 524 pstrcat(se->idstr, sizeof(se->idstr), idstr); 525 526 if (instance_id == -1) { 527 se->instance_id = calculate_new_instance_id(se->idstr); 528 } else { 529 se->instance_id = instance_id; 530 } 531 assert(!se->compat || se->instance_id == 0); 532 /* add at the end of list */ 533 QTAILQ_INSERT_TAIL(&savevm_state.handlers, se, entry); 534 return 0; 535 } 536 537 int register_savevm(DeviceState *dev, 538 const char *idstr, 539 int instance_id, 540 int version_id, 541 SaveStateHandler *save_state, 542 LoadStateHandler *load_state, 543 void *opaque) 544 { 545 SaveVMHandlers *ops = g_new0(SaveVMHandlers, 1); 546 ops->save_state = save_state; 547 ops->load_state = load_state; 548 return register_savevm_live(dev, idstr, instance_id, version_id, 549 ops, opaque); 550 } 551 552 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque) 553 { 554 SaveStateEntry *se, *new_se; 555 char id[256] = ""; 556 557 if (dev) { 558 char *path = qdev_get_dev_path(dev); 559 if (path) { 560 pstrcpy(id, sizeof(id), path); 561 pstrcat(id, sizeof(id), "/"); 562 g_free(path); 563 } 564 } 565 pstrcat(id, sizeof(id), idstr); 566 567 QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { 568 if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) { 569 QTAILQ_REMOVE(&savevm_state.handlers, se, entry); 570 g_free(se->compat); 571 g_free(se->ops); 572 g_free(se); 573 } 574 } 575 } 576 577 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id, 578 const VMStateDescription *vmsd, 579 void *opaque, int alias_id, 580 int required_for_version) 581 { 582 SaveStateEntry *se; 583 584 /* If this triggers, alias support can be dropped for the vmsd. */ 585 assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id); 586 587 se = g_new0(SaveStateEntry, 1); 588 se->version_id = vmsd->version_id; 589 se->section_id = savevm_state.global_section_id++; 590 se->opaque = opaque; 591 se->vmsd = vmsd; 592 se->alias_id = alias_id; 593 594 if (dev) { 595 char *id = qdev_get_dev_path(dev); 596 if (id) { 597 pstrcpy(se->idstr, sizeof(se->idstr), id); 598 pstrcat(se->idstr, sizeof(se->idstr), "/"); 599 g_free(id); 600 601 se->compat = g_new0(CompatEntry, 1); 602 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name); 603 se->compat->instance_id = instance_id == -1 ? 604 calculate_compat_instance_id(vmsd->name) : instance_id; 605 instance_id = -1; 606 } 607 } 608 pstrcat(se->idstr, sizeof(se->idstr), vmsd->name); 609 610 if (instance_id == -1) { 611 se->instance_id = calculate_new_instance_id(se->idstr); 612 } else { 613 se->instance_id = instance_id; 614 } 615 assert(!se->compat || se->instance_id == 0); 616 /* add at the end of list */ 617 QTAILQ_INSERT_TAIL(&savevm_state.handlers, se, entry); 618 return 0; 619 } 620 621 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd, 622 void *opaque) 623 { 624 SaveStateEntry *se, *new_se; 625 626 QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { 627 if (se->vmsd == vmsd && se->opaque == opaque) { 628 QTAILQ_REMOVE(&savevm_state.handlers, se, entry); 629 g_free(se->compat); 630 g_free(se); 631 } 632 } 633 } 634 635 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) 636 { 637 trace_vmstate_load(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); 638 if (!se->vmsd) { /* Old style */ 639 return se->ops->load_state(f, se->opaque, version_id); 640 } 641 return vmstate_load_state(f, se->vmsd, se->opaque, version_id); 642 } 643 644 static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) 645 { 646 int64_t old_offset, size; 647 648 old_offset = qemu_ftell_fast(f); 649 se->ops->save_state(f, se->opaque); 650 size = qemu_ftell_fast(f) - old_offset; 651 652 if (vmdesc) { 653 json_prop_int(vmdesc, "size", size); 654 json_start_array(vmdesc, "fields"); 655 json_start_object(vmdesc, NULL); 656 json_prop_str(vmdesc, "name", "data"); 657 json_prop_int(vmdesc, "size", size); 658 json_prop_str(vmdesc, "type", "buffer"); 659 json_end_object(vmdesc); 660 json_end_array(vmdesc); 661 } 662 } 663 664 static void vmstate_save(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) 665 { 666 trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); 667 if (!se->vmsd) { 668 vmstate_save_old_style(f, se, vmdesc); 669 return; 670 } 671 vmstate_save_state(f, se->vmsd, se->opaque, vmdesc); 672 } 673 674 void savevm_skip_section_footers(void) 675 { 676 skip_section_footers = true; 677 } 678 679 /* 680 * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL) 681 */ 682 static void save_section_header(QEMUFile *f, SaveStateEntry *se, 683 uint8_t section_type) 684 { 685 qemu_put_byte(f, section_type); 686 qemu_put_be32(f, se->section_id); 687 688 if (section_type == QEMU_VM_SECTION_FULL || 689 section_type == QEMU_VM_SECTION_START) { 690 /* ID string */ 691 size_t len = strlen(se->idstr); 692 qemu_put_byte(f, len); 693 qemu_put_buffer(f, (uint8_t *)se->idstr, len); 694 695 qemu_put_be32(f, se->instance_id); 696 qemu_put_be32(f, se->version_id); 697 } 698 } 699 700 /* 701 * Write a footer onto device sections that catches cases misformatted device 702 * sections. 703 */ 704 static void save_section_footer(QEMUFile *f, SaveStateEntry *se) 705 { 706 if (!skip_section_footers) { 707 qemu_put_byte(f, QEMU_VM_SECTION_FOOTER); 708 qemu_put_be32(f, se->section_id); 709 } 710 } 711 712 /** 713 * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the 714 * command and associated data. 715 * 716 * @f: File to send command on 717 * @command: Command type to send 718 * @len: Length of associated data 719 * @data: Data associated with command. 720 */ 721 void qemu_savevm_command_send(QEMUFile *f, 722 enum qemu_vm_cmd command, 723 uint16_t len, 724 uint8_t *data) 725 { 726 trace_savevm_command_send(command, len); 727 qemu_put_byte(f, QEMU_VM_COMMAND); 728 qemu_put_be16(f, (uint16_t)command); 729 qemu_put_be16(f, len); 730 qemu_put_buffer(f, data, len); 731 qemu_fflush(f); 732 } 733 734 void qemu_savevm_send_ping(QEMUFile *f, uint32_t value) 735 { 736 uint32_t buf; 737 738 trace_savevm_send_ping(value); 739 buf = cpu_to_be32(value); 740 qemu_savevm_command_send(f, MIG_CMD_PING, sizeof(value), (uint8_t *)&buf); 741 } 742 743 void qemu_savevm_send_open_return_path(QEMUFile *f) 744 { 745 trace_savevm_send_open_return_path(); 746 qemu_savevm_command_send(f, MIG_CMD_OPEN_RETURN_PATH, 0, NULL); 747 } 748 749 /* We have a buffer of data to send; we don't want that all to be loaded 750 * by the command itself, so the command contains just the length of the 751 * extra buffer that we then send straight after it. 752 * TODO: Must be a better way to organise that 753 * 754 * Returns: 755 * 0 on success 756 * -ve on error 757 */ 758 int qemu_savevm_send_packaged(QEMUFile *f, const uint8_t *buf, size_t len) 759 { 760 uint32_t tmp; 761 762 if (len > MAX_VM_CMD_PACKAGED_SIZE) { 763 error_report("%s: Unreasonably large packaged state: %zu", 764 __func__, len); 765 return -1; 766 } 767 768 tmp = cpu_to_be32(len); 769 770 trace_qemu_savevm_send_packaged(); 771 qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); 772 773 qemu_put_buffer(f, buf, len); 774 775 return 0; 776 } 777 778 /* Send prior to any postcopy transfer */ 779 void qemu_savevm_send_postcopy_advise(QEMUFile *f) 780 { 781 uint64_t tmp[2]; 782 tmp[0] = cpu_to_be64(getpagesize()); 783 tmp[1] = cpu_to_be64(1ul << qemu_target_page_bits()); 784 785 trace_qemu_savevm_send_postcopy_advise(); 786 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_ADVISE, 16, (uint8_t *)tmp); 787 } 788 789 /* Sent prior to starting the destination running in postcopy, discard pages 790 * that have already been sent but redirtied on the source. 791 * CMD_POSTCOPY_RAM_DISCARD consist of: 792 * byte version (0) 793 * byte Length of name field (not including 0) 794 * n x byte RAM block name 795 * byte 0 terminator (just for safety) 796 * n x Byte ranges within the named RAMBlock 797 * be64 Start of the range 798 * be64 Length 799 * 800 * name: RAMBlock name that these entries are part of 801 * len: Number of page entries 802 * start_list: 'len' addresses 803 * length_list: 'len' addresses 804 * 805 */ 806 void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name, 807 uint16_t len, 808 uint64_t *start_list, 809 uint64_t *length_list) 810 { 811 uint8_t *buf; 812 uint16_t tmplen; 813 uint16_t t; 814 size_t name_len = strlen(name); 815 816 trace_qemu_savevm_send_postcopy_ram_discard(name, len); 817 assert(name_len < 256); 818 buf = g_malloc0(1 + 1 + name_len + 1 + (8 + 8) * len); 819 buf[0] = postcopy_ram_discard_version; 820 buf[1] = name_len; 821 memcpy(buf + 2, name, name_len); 822 tmplen = 2 + name_len; 823 buf[tmplen++] = '\0'; 824 825 for (t = 0; t < len; t++) { 826 cpu_to_be64w((uint64_t *)(buf + tmplen), start_list[t]); 827 tmplen += 8; 828 cpu_to_be64w((uint64_t *)(buf + tmplen), length_list[t]); 829 tmplen += 8; 830 } 831 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RAM_DISCARD, tmplen, buf); 832 g_free(buf); 833 } 834 835 /* Get the destination into a state where it can receive postcopy data. */ 836 void qemu_savevm_send_postcopy_listen(QEMUFile *f) 837 { 838 trace_savevm_send_postcopy_listen(); 839 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_LISTEN, 0, NULL); 840 } 841 842 /* Kick the destination into running */ 843 void qemu_savevm_send_postcopy_run(QEMUFile *f) 844 { 845 trace_savevm_send_postcopy_run(); 846 qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RUN, 0, NULL); 847 } 848 849 bool qemu_savevm_state_blocked(Error **errp) 850 { 851 SaveStateEntry *se; 852 853 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 854 if (se->vmsd && se->vmsd->unmigratable) { 855 error_setg(errp, "State blocked by non-migratable device '%s'", 856 se->idstr); 857 return true; 858 } 859 } 860 return false; 861 } 862 863 static bool enforce_config_section(void) 864 { 865 MachineState *machine = MACHINE(qdev_get_machine()); 866 return machine->enforce_config_section; 867 } 868 869 void qemu_savevm_state_header(QEMUFile *f) 870 { 871 trace_savevm_state_header(); 872 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 873 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 874 875 if (!savevm_state.skip_configuration || enforce_config_section()) { 876 qemu_put_byte(f, QEMU_VM_CONFIGURATION); 877 vmstate_save_state(f, &vmstate_configuration, &savevm_state, 0); 878 } 879 880 } 881 882 void qemu_savevm_state_begin(QEMUFile *f, 883 const MigrationParams *params) 884 { 885 SaveStateEntry *se; 886 int ret; 887 888 trace_savevm_state_begin(); 889 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 890 if (!se->ops || !se->ops->set_params) { 891 continue; 892 } 893 se->ops->set_params(params, se->opaque); 894 } 895 896 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 897 if (!se->ops || !se->ops->save_live_setup) { 898 continue; 899 } 900 if (se->ops && se->ops->is_active) { 901 if (!se->ops->is_active(se->opaque)) { 902 continue; 903 } 904 } 905 save_section_header(f, se, QEMU_VM_SECTION_START); 906 907 ret = se->ops->save_live_setup(f, se->opaque); 908 save_section_footer(f, se); 909 if (ret < 0) { 910 qemu_file_set_error(f, ret); 911 break; 912 } 913 } 914 } 915 916 /* 917 * this function has three return values: 918 * negative: there was one error, and we have -errno. 919 * 0 : We haven't finished, caller have to go again 920 * 1 : We have finished, we can go to complete phase 921 */ 922 int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy) 923 { 924 SaveStateEntry *se; 925 int ret = 1; 926 927 trace_savevm_state_iterate(); 928 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 929 if (!se->ops || !se->ops->save_live_iterate) { 930 continue; 931 } 932 if (se->ops && se->ops->is_active) { 933 if (!se->ops->is_active(se->opaque)) { 934 continue; 935 } 936 } 937 /* 938 * In the postcopy phase, any device that doesn't know how to 939 * do postcopy should have saved it's state in the _complete 940 * call that's already run, it might get confused if we call 941 * iterate afterwards. 942 */ 943 if (postcopy && !se->ops->save_live_complete_postcopy) { 944 continue; 945 } 946 if (qemu_file_rate_limit(f)) { 947 return 0; 948 } 949 trace_savevm_section_start(se->idstr, se->section_id); 950 951 save_section_header(f, se, QEMU_VM_SECTION_PART); 952 953 ret = se->ops->save_live_iterate(f, se->opaque); 954 trace_savevm_section_end(se->idstr, se->section_id, ret); 955 save_section_footer(f, se); 956 957 if (ret < 0) { 958 qemu_file_set_error(f, ret); 959 } 960 if (ret <= 0) { 961 /* Do not proceed to the next vmstate before this one reported 962 completion of the current stage. This serializes the migration 963 and reduces the probability that a faster changing state is 964 synchronized over and over again. */ 965 break; 966 } 967 } 968 return ret; 969 } 970 971 static bool should_send_vmdesc(void) 972 { 973 MachineState *machine = MACHINE(qdev_get_machine()); 974 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 975 return !machine->suppress_vmdesc && !in_postcopy; 976 } 977 978 /* 979 * Calls the save_live_complete_postcopy methods 980 * causing the last few pages to be sent immediately and doing any associated 981 * cleanup. 982 * Note postcopy also calls qemu_savevm_state_complete_precopy to complete 983 * all the other devices, but that happens at the point we switch to postcopy. 984 */ 985 void qemu_savevm_state_complete_postcopy(QEMUFile *f) 986 { 987 SaveStateEntry *se; 988 int ret; 989 990 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 991 if (!se->ops || !se->ops->save_live_complete_postcopy) { 992 continue; 993 } 994 if (se->ops && se->ops->is_active) { 995 if (!se->ops->is_active(se->opaque)) { 996 continue; 997 } 998 } 999 trace_savevm_section_start(se->idstr, se->section_id); 1000 /* Section type */ 1001 qemu_put_byte(f, QEMU_VM_SECTION_END); 1002 qemu_put_be32(f, se->section_id); 1003 1004 ret = se->ops->save_live_complete_postcopy(f, se->opaque); 1005 trace_savevm_section_end(se->idstr, se->section_id, ret); 1006 save_section_footer(f, se); 1007 if (ret < 0) { 1008 qemu_file_set_error(f, ret); 1009 return; 1010 } 1011 } 1012 1013 qemu_put_byte(f, QEMU_VM_EOF); 1014 qemu_fflush(f); 1015 } 1016 1017 void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) 1018 { 1019 QJSON *vmdesc; 1020 int vmdesc_len; 1021 SaveStateEntry *se; 1022 int ret; 1023 bool in_postcopy = migration_in_postcopy(migrate_get_current()); 1024 1025 trace_savevm_state_complete_precopy(); 1026 1027 cpu_synchronize_all_states(); 1028 1029 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1030 if (!se->ops || 1031 (in_postcopy && se->ops->save_live_complete_postcopy) || 1032 (in_postcopy && !iterable_only) || 1033 !se->ops->save_live_complete_precopy) { 1034 continue; 1035 } 1036 1037 if (se->ops && se->ops->is_active) { 1038 if (!se->ops->is_active(se->opaque)) { 1039 continue; 1040 } 1041 } 1042 trace_savevm_section_start(se->idstr, se->section_id); 1043 1044 save_section_header(f, se, QEMU_VM_SECTION_END); 1045 1046 ret = se->ops->save_live_complete_precopy(f, se->opaque); 1047 trace_savevm_section_end(se->idstr, se->section_id, ret); 1048 save_section_footer(f, se); 1049 if (ret < 0) { 1050 qemu_file_set_error(f, ret); 1051 return; 1052 } 1053 } 1054 1055 if (iterable_only) { 1056 return; 1057 } 1058 1059 vmdesc = qjson_new(); 1060 json_prop_int(vmdesc, "page_size", TARGET_PAGE_SIZE); 1061 json_start_array(vmdesc, "devices"); 1062 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1063 1064 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1065 continue; 1066 } 1067 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1068 trace_savevm_section_skip(se->idstr, se->section_id); 1069 continue; 1070 } 1071 1072 trace_savevm_section_start(se->idstr, se->section_id); 1073 1074 json_start_object(vmdesc, NULL); 1075 json_prop_str(vmdesc, "name", se->idstr); 1076 json_prop_int(vmdesc, "instance_id", se->instance_id); 1077 1078 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1079 vmstate_save(f, se, vmdesc); 1080 trace_savevm_section_end(se->idstr, se->section_id, 0); 1081 save_section_footer(f, se); 1082 1083 json_end_object(vmdesc); 1084 } 1085 1086 if (!in_postcopy) { 1087 /* Postcopy stream will still be going */ 1088 qemu_put_byte(f, QEMU_VM_EOF); 1089 } 1090 1091 json_end_array(vmdesc); 1092 qjson_finish(vmdesc); 1093 vmdesc_len = strlen(qjson_get_str(vmdesc)); 1094 1095 if (should_send_vmdesc()) { 1096 qemu_put_byte(f, QEMU_VM_VMDESCRIPTION); 1097 qemu_put_be32(f, vmdesc_len); 1098 qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len); 1099 } 1100 qjson_destroy(vmdesc); 1101 1102 qemu_fflush(f); 1103 } 1104 1105 /* Give an estimate of the amount left to be transferred, 1106 * the result is split into the amount for units that can and 1107 * for units that can't do postcopy. 1108 */ 1109 void qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size, 1110 uint64_t *res_non_postcopiable, 1111 uint64_t *res_postcopiable) 1112 { 1113 SaveStateEntry *se; 1114 1115 *res_non_postcopiable = 0; 1116 *res_postcopiable = 0; 1117 1118 1119 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1120 if (!se->ops || !se->ops->save_live_pending) { 1121 continue; 1122 } 1123 if (se->ops && se->ops->is_active) { 1124 if (!se->ops->is_active(se->opaque)) { 1125 continue; 1126 } 1127 } 1128 se->ops->save_live_pending(f, se->opaque, max_size, 1129 res_non_postcopiable, res_postcopiable); 1130 } 1131 } 1132 1133 void qemu_savevm_state_cleanup(void) 1134 { 1135 SaveStateEntry *se; 1136 1137 trace_savevm_state_cleanup(); 1138 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1139 if (se->ops && se->ops->cleanup) { 1140 se->ops->cleanup(se->opaque); 1141 } 1142 } 1143 } 1144 1145 static int qemu_savevm_state(QEMUFile *f, Error **errp) 1146 { 1147 int ret; 1148 MigrationParams params = { 1149 .blk = 0, 1150 .shared = 0 1151 }; 1152 MigrationState *ms = migrate_init(¶ms); 1153 ms->to_dst_file = f; 1154 1155 if (migration_is_blocked(errp)) { 1156 return -EINVAL; 1157 } 1158 1159 qemu_mutex_unlock_iothread(); 1160 qemu_savevm_state_header(f); 1161 qemu_savevm_state_begin(f, ¶ms); 1162 qemu_mutex_lock_iothread(); 1163 1164 while (qemu_file_get_error(f) == 0) { 1165 if (qemu_savevm_state_iterate(f, false) > 0) { 1166 break; 1167 } 1168 } 1169 1170 ret = qemu_file_get_error(f); 1171 if (ret == 0) { 1172 qemu_savevm_state_complete_precopy(f, false); 1173 ret = qemu_file_get_error(f); 1174 } 1175 qemu_savevm_state_cleanup(); 1176 if (ret != 0) { 1177 error_setg_errno(errp, -ret, "Error while writing VM state"); 1178 } 1179 return ret; 1180 } 1181 1182 static int qemu_save_device_state(QEMUFile *f) 1183 { 1184 SaveStateEntry *se; 1185 1186 qemu_put_be32(f, QEMU_VM_FILE_MAGIC); 1187 qemu_put_be32(f, QEMU_VM_FILE_VERSION); 1188 1189 cpu_synchronize_all_states(); 1190 1191 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1192 if (se->is_ram) { 1193 continue; 1194 } 1195 if ((!se->ops || !se->ops->save_state) && !se->vmsd) { 1196 continue; 1197 } 1198 if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { 1199 continue; 1200 } 1201 1202 save_section_header(f, se, QEMU_VM_SECTION_FULL); 1203 1204 vmstate_save(f, se, NULL); 1205 1206 save_section_footer(f, se); 1207 } 1208 1209 qemu_put_byte(f, QEMU_VM_EOF); 1210 1211 return qemu_file_get_error(f); 1212 } 1213 1214 static SaveStateEntry *find_se(const char *idstr, int instance_id) 1215 { 1216 SaveStateEntry *se; 1217 1218 QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { 1219 if (!strcmp(se->idstr, idstr) && 1220 (instance_id == se->instance_id || 1221 instance_id == se->alias_id)) 1222 return se; 1223 /* Migrating from an older version? */ 1224 if (strstr(se->idstr, idstr) && se->compat) { 1225 if (!strcmp(se->compat->idstr, idstr) && 1226 (instance_id == se->compat->instance_id || 1227 instance_id == se->alias_id)) 1228 return se; 1229 } 1230 } 1231 return NULL; 1232 } 1233 1234 enum LoadVMExitCodes { 1235 /* Allow a command to quit all layers of nested loadvm loops */ 1236 LOADVM_QUIT = 1, 1237 }; 1238 1239 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis); 1240 1241 /* ------ incoming postcopy messages ------ */ 1242 /* 'advise' arrives before any transfers just to tell us that a postcopy 1243 * *might* happen - it might be skipped if precopy transferred everything 1244 * quickly. 1245 */ 1246 static int loadvm_postcopy_handle_advise(MigrationIncomingState *mis) 1247 { 1248 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1249 uint64_t remote_hps, remote_tps; 1250 1251 trace_loadvm_postcopy_handle_advise(); 1252 if (ps != POSTCOPY_INCOMING_NONE) { 1253 error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps); 1254 return -1; 1255 } 1256 1257 if (!postcopy_ram_supported_by_host()) { 1258 return -1; 1259 } 1260 1261 remote_hps = qemu_get_be64(mis->from_src_file); 1262 if (remote_hps != getpagesize()) { 1263 /* 1264 * Some combinations of mismatch are probably possible but it gets 1265 * a bit more complicated. In particular we need to place whole 1266 * host pages on the dest at once, and we need to ensure that we 1267 * handle dirtying to make sure we never end up sending part of 1268 * a hostpage on it's own. 1269 */ 1270 error_report("Postcopy needs matching host page sizes (s=%d d=%d)", 1271 (int)remote_hps, getpagesize()); 1272 return -1; 1273 } 1274 1275 remote_tps = qemu_get_be64(mis->from_src_file); 1276 if (remote_tps != (1ul << qemu_target_page_bits())) { 1277 /* 1278 * Again, some differences could be dealt with, but for now keep it 1279 * simple. 1280 */ 1281 error_report("Postcopy needs matching target page sizes (s=%d d=%d)", 1282 (int)remote_tps, 1 << qemu_target_page_bits()); 1283 return -1; 1284 } 1285 1286 if (ram_postcopy_incoming_init(mis)) { 1287 return -1; 1288 } 1289 1290 postcopy_state_set(POSTCOPY_INCOMING_ADVISE); 1291 1292 return 0; 1293 } 1294 1295 /* After postcopy we will be told to throw some pages away since they're 1296 * dirty and will have to be demand fetched. Must happen before CPU is 1297 * started. 1298 * There can be 0..many of these messages, each encoding multiple pages. 1299 */ 1300 static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState *mis, 1301 uint16_t len) 1302 { 1303 int tmp; 1304 char ramid[256]; 1305 PostcopyState ps = postcopy_state_get(); 1306 1307 trace_loadvm_postcopy_ram_handle_discard(); 1308 1309 switch (ps) { 1310 case POSTCOPY_INCOMING_ADVISE: 1311 /* 1st discard */ 1312 tmp = postcopy_ram_prepare_discard(mis); 1313 if (tmp) { 1314 return tmp; 1315 } 1316 break; 1317 1318 case POSTCOPY_INCOMING_DISCARD: 1319 /* Expected state */ 1320 break; 1321 1322 default: 1323 error_report("CMD_POSTCOPY_RAM_DISCARD in wrong postcopy state (%d)", 1324 ps); 1325 return -1; 1326 } 1327 /* We're expecting a 1328 * Version (0) 1329 * a RAM ID string (length byte, name, 0 term) 1330 * then at least 1 16 byte chunk 1331 */ 1332 if (len < (1 + 1 + 1 + 1 + 2 * 8)) { 1333 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1334 return -1; 1335 } 1336 1337 tmp = qemu_get_byte(mis->from_src_file); 1338 if (tmp != postcopy_ram_discard_version) { 1339 error_report("CMD_POSTCOPY_RAM_DISCARD invalid version (%d)", tmp); 1340 return -1; 1341 } 1342 1343 if (!qemu_get_counted_string(mis->from_src_file, ramid)) { 1344 error_report("CMD_POSTCOPY_RAM_DISCARD Failed to read RAMBlock ID"); 1345 return -1; 1346 } 1347 tmp = qemu_get_byte(mis->from_src_file); 1348 if (tmp != 0) { 1349 error_report("CMD_POSTCOPY_RAM_DISCARD missing nil (%d)", tmp); 1350 return -1; 1351 } 1352 1353 len -= 3 + strlen(ramid); 1354 if (len % 16) { 1355 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); 1356 return -1; 1357 } 1358 trace_loadvm_postcopy_ram_handle_discard_header(ramid, len); 1359 while (len) { 1360 uint64_t start_addr, block_length; 1361 start_addr = qemu_get_be64(mis->from_src_file); 1362 block_length = qemu_get_be64(mis->from_src_file); 1363 1364 len -= 16; 1365 int ret = ram_discard_range(mis, ramid, start_addr, 1366 block_length); 1367 if (ret) { 1368 return ret; 1369 } 1370 } 1371 trace_loadvm_postcopy_ram_handle_discard_end(); 1372 1373 return 0; 1374 } 1375 1376 /* 1377 * Triggered by a postcopy_listen command; this thread takes over reading 1378 * the input stream, leaving the main thread free to carry on loading the rest 1379 * of the device state (from RAM). 1380 * (TODO:This could do with being in a postcopy file - but there again it's 1381 * just another input loop, not that postcopy specific) 1382 */ 1383 static void *postcopy_ram_listen_thread(void *opaque) 1384 { 1385 QEMUFile *f = opaque; 1386 MigrationIncomingState *mis = migration_incoming_get_current(); 1387 int load_res; 1388 1389 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, 1390 MIGRATION_STATUS_POSTCOPY_ACTIVE); 1391 qemu_sem_post(&mis->listen_thread_sem); 1392 trace_postcopy_ram_listen_thread_start(); 1393 1394 /* 1395 * Because we're a thread and not a coroutine we can't yield 1396 * in qemu_file, and thus we must be blocking now. 1397 */ 1398 qemu_file_set_blocking(f, true); 1399 load_res = qemu_loadvm_state_main(f, mis); 1400 /* And non-blocking again so we don't block in any cleanup */ 1401 qemu_file_set_blocking(f, false); 1402 1403 trace_postcopy_ram_listen_thread_exit(); 1404 if (load_res < 0) { 1405 error_report("%s: loadvm failed: %d", __func__, load_res); 1406 qemu_file_set_error(f, load_res); 1407 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1408 MIGRATION_STATUS_FAILED); 1409 } else { 1410 /* 1411 * This looks good, but it's possible that the device loading in the 1412 * main thread hasn't finished yet, and so we might not be in 'RUN' 1413 * state yet; wait for the end of the main thread. 1414 */ 1415 qemu_event_wait(&mis->main_thread_load_event); 1416 } 1417 postcopy_ram_incoming_cleanup(mis); 1418 1419 if (load_res < 0) { 1420 /* 1421 * If something went wrong then we have a bad state so exit; 1422 * depending how far we got it might be possible at this point 1423 * to leave the guest running and fire MCEs for pages that never 1424 * arrived as a desperate recovery step. 1425 */ 1426 exit(EXIT_FAILURE); 1427 } 1428 1429 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1430 MIGRATION_STATUS_COMPLETED); 1431 /* 1432 * If everything has worked fine, then the main thread has waited 1433 * for us to start, and we're the last use of the mis. 1434 * (If something broke then qemu will have to exit anyway since it's 1435 * got a bad migration state). 1436 */ 1437 migration_incoming_state_destroy(); 1438 1439 1440 return NULL; 1441 } 1442 1443 /* After this message we must be able to immediately receive postcopy data */ 1444 static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) 1445 { 1446 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING); 1447 trace_loadvm_postcopy_handle_listen(); 1448 if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) { 1449 error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps); 1450 return -1; 1451 } 1452 if (ps == POSTCOPY_INCOMING_ADVISE) { 1453 /* 1454 * A rare case, we entered listen without having to do any discards, 1455 * so do the setup that's normally done at the time of the 1st discard. 1456 */ 1457 postcopy_ram_prepare_discard(mis); 1458 } 1459 1460 /* 1461 * Sensitise RAM - can now generate requests for blocks that don't exist 1462 * However, at this point the CPU shouldn't be running, and the IO 1463 * shouldn't be doing anything yet so don't actually expect requests 1464 */ 1465 if (postcopy_ram_enable_notify(mis)) { 1466 return -1; 1467 } 1468 1469 if (mis->have_listen_thread) { 1470 error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread"); 1471 return -1; 1472 } 1473 1474 mis->have_listen_thread = true; 1475 /* Start up the listening thread and wait for it to signal ready */ 1476 qemu_sem_init(&mis->listen_thread_sem, 0); 1477 qemu_thread_create(&mis->listen_thread, "postcopy/listen", 1478 postcopy_ram_listen_thread, mis->from_src_file, 1479 QEMU_THREAD_DETACHED); 1480 qemu_sem_wait(&mis->listen_thread_sem); 1481 qemu_sem_destroy(&mis->listen_thread_sem); 1482 1483 return 0; 1484 } 1485 1486 1487 typedef struct { 1488 QEMUBH *bh; 1489 } HandleRunBhData; 1490 1491 static void loadvm_postcopy_handle_run_bh(void *opaque) 1492 { 1493 Error *local_err = NULL; 1494 HandleRunBhData *data = opaque; 1495 1496 /* TODO we should move all of this lot into postcopy_ram.c or a shared code 1497 * in migration.c 1498 */ 1499 cpu_synchronize_all_post_init(); 1500 1501 qemu_announce_self(); 1502 1503 /* Make sure all file formats flush their mutable metadata */ 1504 bdrv_invalidate_cache_all(&local_err); 1505 if (local_err) { 1506 error_report_err(local_err); 1507 } 1508 1509 trace_loadvm_postcopy_handle_run_cpu_sync(); 1510 cpu_synchronize_all_post_init(); 1511 1512 trace_loadvm_postcopy_handle_run_vmstart(); 1513 1514 if (autostart) { 1515 /* Hold onto your hats, starting the CPU */ 1516 vm_start(); 1517 } else { 1518 /* leave it paused and let management decide when to start the CPU */ 1519 runstate_set(RUN_STATE_PAUSED); 1520 } 1521 1522 qemu_bh_delete(data->bh); 1523 g_free(data); 1524 } 1525 1526 /* After all discards we can start running and asking for pages */ 1527 static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) 1528 { 1529 PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_RUNNING); 1530 HandleRunBhData *data; 1531 1532 trace_loadvm_postcopy_handle_run(); 1533 if (ps != POSTCOPY_INCOMING_LISTENING) { 1534 error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps); 1535 return -1; 1536 } 1537 1538 data = g_new(HandleRunBhData, 1); 1539 data->bh = qemu_bh_new(loadvm_postcopy_handle_run_bh, data); 1540 qemu_bh_schedule(data->bh); 1541 1542 /* We need to finish reading the stream from the package 1543 * and also stop reading anything more from the stream that loaded the 1544 * package (since it's now being read by the listener thread). 1545 * LOADVM_QUIT will quit all the layers of nested loadvm loops. 1546 */ 1547 return LOADVM_QUIT; 1548 } 1549 1550 /** 1551 * Immediately following this command is a blob of data containing an embedded 1552 * chunk of migration stream; read it and load it. 1553 * 1554 * @mis: Incoming state 1555 * @length: Length of packaged data to read 1556 * 1557 * Returns: Negative values on error 1558 * 1559 */ 1560 static int loadvm_handle_cmd_packaged(MigrationIncomingState *mis) 1561 { 1562 int ret; 1563 size_t length; 1564 QIOChannelBuffer *bioc; 1565 1566 length = qemu_get_be32(mis->from_src_file); 1567 trace_loadvm_handle_cmd_packaged(length); 1568 1569 if (length > MAX_VM_CMD_PACKAGED_SIZE) { 1570 error_report("Unreasonably large packaged state: %zu", length); 1571 return -1; 1572 } 1573 1574 bioc = qio_channel_buffer_new(length); 1575 ret = qemu_get_buffer(mis->from_src_file, 1576 bioc->data, 1577 length); 1578 if (ret != length) { 1579 object_unref(OBJECT(bioc)); 1580 error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%zu", 1581 ret, length); 1582 return (ret < 0) ? ret : -EAGAIN; 1583 } 1584 bioc->usage += length; 1585 trace_loadvm_handle_cmd_packaged_received(ret); 1586 1587 QEMUFile *packf = qemu_fopen_channel_input(QIO_CHANNEL(bioc)); 1588 1589 ret = qemu_loadvm_state_main(packf, mis); 1590 trace_loadvm_handle_cmd_packaged_main(ret); 1591 qemu_fclose(packf); 1592 object_unref(OBJECT(bioc)); 1593 1594 return ret; 1595 } 1596 1597 /* 1598 * Process an incoming 'QEMU_VM_COMMAND' 1599 * 0 just a normal return 1600 * LOADVM_QUIT All good, but exit the loop 1601 * <0 Error 1602 */ 1603 static int loadvm_process_command(QEMUFile *f) 1604 { 1605 MigrationIncomingState *mis = migration_incoming_get_current(); 1606 uint16_t cmd; 1607 uint16_t len; 1608 uint32_t tmp32; 1609 1610 cmd = qemu_get_be16(f); 1611 len = qemu_get_be16(f); 1612 1613 trace_loadvm_process_command(cmd, len); 1614 if (cmd >= MIG_CMD_MAX || cmd == MIG_CMD_INVALID) { 1615 error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd, len); 1616 return -EINVAL; 1617 } 1618 1619 if (mig_cmd_args[cmd].len != -1 && mig_cmd_args[cmd].len != len) { 1620 error_report("%s received with bad length - expecting %zu, got %d", 1621 mig_cmd_args[cmd].name, 1622 (size_t)mig_cmd_args[cmd].len, len); 1623 return -ERANGE; 1624 } 1625 1626 switch (cmd) { 1627 case MIG_CMD_OPEN_RETURN_PATH: 1628 if (mis->to_src_file) { 1629 error_report("CMD_OPEN_RETURN_PATH called when RP already open"); 1630 /* Not really a problem, so don't give up */ 1631 return 0; 1632 } 1633 mis->to_src_file = qemu_file_get_return_path(f); 1634 if (!mis->to_src_file) { 1635 error_report("CMD_OPEN_RETURN_PATH failed"); 1636 return -1; 1637 } 1638 break; 1639 1640 case MIG_CMD_PING: 1641 tmp32 = qemu_get_be32(f); 1642 trace_loadvm_process_command_ping(tmp32); 1643 if (!mis->to_src_file) { 1644 error_report("CMD_PING (0x%x) received with no return path", 1645 tmp32); 1646 return -1; 1647 } 1648 migrate_send_rp_pong(mis, tmp32); 1649 break; 1650 1651 case MIG_CMD_PACKAGED: 1652 return loadvm_handle_cmd_packaged(mis); 1653 1654 case MIG_CMD_POSTCOPY_ADVISE: 1655 return loadvm_postcopy_handle_advise(mis); 1656 1657 case MIG_CMD_POSTCOPY_LISTEN: 1658 return loadvm_postcopy_handle_listen(mis); 1659 1660 case MIG_CMD_POSTCOPY_RUN: 1661 return loadvm_postcopy_handle_run(mis); 1662 1663 case MIG_CMD_POSTCOPY_RAM_DISCARD: 1664 return loadvm_postcopy_ram_handle_discard(mis, len); 1665 } 1666 1667 return 0; 1668 } 1669 1670 struct LoadStateEntry { 1671 QLIST_ENTRY(LoadStateEntry) entry; 1672 SaveStateEntry *se; 1673 int section_id; 1674 int version_id; 1675 }; 1676 1677 /* 1678 * Read a footer off the wire and check that it matches the expected section 1679 * 1680 * Returns: true if the footer was good 1681 * false if there is a problem (and calls error_report to say why) 1682 */ 1683 static bool check_section_footer(QEMUFile *f, LoadStateEntry *le) 1684 { 1685 uint8_t read_mark; 1686 uint32_t read_section_id; 1687 1688 if (skip_section_footers) { 1689 /* No footer to check */ 1690 return true; 1691 } 1692 1693 read_mark = qemu_get_byte(f); 1694 1695 if (read_mark != QEMU_VM_SECTION_FOOTER) { 1696 error_report("Missing section footer for %s", le->se->idstr); 1697 return false; 1698 } 1699 1700 read_section_id = qemu_get_be32(f); 1701 if (read_section_id != le->section_id) { 1702 error_report("Mismatched section id in footer for %s -" 1703 " read 0x%x expected 0x%x", 1704 le->se->idstr, read_section_id, le->section_id); 1705 return false; 1706 } 1707 1708 /* All good */ 1709 return true; 1710 } 1711 1712 void loadvm_free_handlers(MigrationIncomingState *mis) 1713 { 1714 LoadStateEntry *le, *new_le; 1715 1716 QLIST_FOREACH_SAFE(le, &mis->loadvm_handlers, entry, new_le) { 1717 QLIST_REMOVE(le, entry); 1718 g_free(le); 1719 } 1720 } 1721 1722 static int 1723 qemu_loadvm_section_start_full(QEMUFile *f, MigrationIncomingState *mis) 1724 { 1725 uint32_t instance_id, version_id, section_id; 1726 SaveStateEntry *se; 1727 LoadStateEntry *le; 1728 char idstr[256]; 1729 int ret; 1730 1731 /* Read section start */ 1732 section_id = qemu_get_be32(f); 1733 if (!qemu_get_counted_string(f, idstr)) { 1734 error_report("Unable to read ID string for section %u", 1735 section_id); 1736 return -EINVAL; 1737 } 1738 instance_id = qemu_get_be32(f); 1739 version_id = qemu_get_be32(f); 1740 1741 trace_qemu_loadvm_state_section_startfull(section_id, idstr, 1742 instance_id, version_id); 1743 /* Find savevm section */ 1744 se = find_se(idstr, instance_id); 1745 if (se == NULL) { 1746 error_report("Unknown savevm section or instance '%s' %d", 1747 idstr, instance_id); 1748 return -EINVAL; 1749 } 1750 1751 /* Validate version */ 1752 if (version_id > se->version_id) { 1753 error_report("savevm: unsupported version %d for '%s' v%d", 1754 version_id, idstr, se->version_id); 1755 return -EINVAL; 1756 } 1757 1758 /* Validate if it is a device's state */ 1759 if (xen_enabled() && se->is_ram) { 1760 error_report("loadvm: %s RAM loading not allowed on Xen", idstr); 1761 return -EINVAL; 1762 } 1763 1764 /* Add entry */ 1765 le = g_malloc0(sizeof(*le)); 1766 1767 le->se = se; 1768 le->section_id = section_id; 1769 le->version_id = version_id; 1770 QLIST_INSERT_HEAD(&mis->loadvm_handlers, le, entry); 1771 1772 ret = vmstate_load(f, le->se, le->version_id); 1773 if (ret < 0) { 1774 error_report("error while loading state for instance 0x%x of" 1775 " device '%s'", instance_id, idstr); 1776 return ret; 1777 } 1778 if (!check_section_footer(f, le)) { 1779 return -EINVAL; 1780 } 1781 1782 return 0; 1783 } 1784 1785 static int 1786 qemu_loadvm_section_part_end(QEMUFile *f, MigrationIncomingState *mis) 1787 { 1788 uint32_t section_id; 1789 LoadStateEntry *le; 1790 int ret; 1791 1792 section_id = qemu_get_be32(f); 1793 1794 trace_qemu_loadvm_state_section_partend(section_id); 1795 QLIST_FOREACH(le, &mis->loadvm_handlers, entry) { 1796 if (le->section_id == section_id) { 1797 break; 1798 } 1799 } 1800 if (le == NULL) { 1801 error_report("Unknown savevm section %d", section_id); 1802 return -EINVAL; 1803 } 1804 1805 ret = vmstate_load(f, le->se, le->version_id); 1806 if (ret < 0) { 1807 error_report("error while loading state section id %d(%s)", 1808 section_id, le->se->idstr); 1809 return ret; 1810 } 1811 if (!check_section_footer(f, le)) { 1812 return -EINVAL; 1813 } 1814 1815 return 0; 1816 } 1817 1818 static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis) 1819 { 1820 uint8_t section_type; 1821 int ret; 1822 1823 while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) { 1824 1825 trace_qemu_loadvm_state_section(section_type); 1826 switch (section_type) { 1827 case QEMU_VM_SECTION_START: 1828 case QEMU_VM_SECTION_FULL: 1829 ret = qemu_loadvm_section_start_full(f, mis); 1830 if (ret < 0) { 1831 return ret; 1832 } 1833 break; 1834 case QEMU_VM_SECTION_PART: 1835 case QEMU_VM_SECTION_END: 1836 ret = qemu_loadvm_section_part_end(f, mis); 1837 if (ret < 0) { 1838 return ret; 1839 } 1840 break; 1841 case QEMU_VM_COMMAND: 1842 ret = loadvm_process_command(f); 1843 trace_qemu_loadvm_state_section_command(ret); 1844 if ((ret < 0) || (ret & LOADVM_QUIT)) { 1845 return ret; 1846 } 1847 break; 1848 default: 1849 error_report("Unknown savevm section type %d", section_type); 1850 return -EINVAL; 1851 } 1852 } 1853 1854 return 0; 1855 } 1856 1857 int qemu_loadvm_state(QEMUFile *f) 1858 { 1859 MigrationIncomingState *mis = migration_incoming_get_current(); 1860 Error *local_err = NULL; 1861 unsigned int v; 1862 int ret; 1863 1864 if (qemu_savevm_state_blocked(&local_err)) { 1865 error_report_err(local_err); 1866 return -EINVAL; 1867 } 1868 1869 v = qemu_get_be32(f); 1870 if (v != QEMU_VM_FILE_MAGIC) { 1871 error_report("Not a migration stream"); 1872 return -EINVAL; 1873 } 1874 1875 v = qemu_get_be32(f); 1876 if (v == QEMU_VM_FILE_VERSION_COMPAT) { 1877 error_report("SaveVM v2 format is obsolete and don't work anymore"); 1878 return -ENOTSUP; 1879 } 1880 if (v != QEMU_VM_FILE_VERSION) { 1881 error_report("Unsupported migration stream version"); 1882 return -ENOTSUP; 1883 } 1884 1885 if (!savevm_state.skip_configuration || enforce_config_section()) { 1886 if (qemu_get_byte(f) != QEMU_VM_CONFIGURATION) { 1887 error_report("Configuration section missing"); 1888 return -EINVAL; 1889 } 1890 ret = vmstate_load_state(f, &vmstate_configuration, &savevm_state, 0); 1891 1892 if (ret) { 1893 return ret; 1894 } 1895 } 1896 1897 ret = qemu_loadvm_state_main(f, mis); 1898 qemu_event_set(&mis->main_thread_load_event); 1899 1900 trace_qemu_loadvm_state_post_main(ret); 1901 1902 if (mis->have_listen_thread) { 1903 /* Listen thread still going, can't clean up yet */ 1904 return ret; 1905 } 1906 1907 if (ret == 0) { 1908 ret = qemu_file_get_error(f); 1909 } 1910 1911 /* 1912 * Try to read in the VMDESC section as well, so that dumping tools that 1913 * intercept our migration stream have the chance to see it. 1914 */ 1915 1916 /* We've got to be careful; if we don't read the data and just shut the fd 1917 * then the sender can error if we close while it's still sending. 1918 * We also mustn't read data that isn't there; some transports (RDMA) 1919 * will stall waiting for that data when the source has already closed. 1920 */ 1921 if (ret == 0 && should_send_vmdesc()) { 1922 uint8_t *buf; 1923 uint32_t size; 1924 uint8_t section_type = qemu_get_byte(f); 1925 1926 if (section_type != QEMU_VM_VMDESCRIPTION) { 1927 error_report("Expected vmdescription section, but got %d", 1928 section_type); 1929 /* 1930 * It doesn't seem worth failing at this point since 1931 * we apparently have an otherwise valid VM state 1932 */ 1933 } else { 1934 buf = g_malloc(0x1000); 1935 size = qemu_get_be32(f); 1936 1937 while (size > 0) { 1938 uint32_t read_chunk = MIN(size, 0x1000); 1939 qemu_get_buffer(f, buf, read_chunk); 1940 size -= read_chunk; 1941 } 1942 g_free(buf); 1943 } 1944 } 1945 1946 cpu_synchronize_all_post_init(); 1947 1948 return ret; 1949 } 1950 1951 void hmp_savevm(Monitor *mon, const QDict *qdict) 1952 { 1953 BlockDriverState *bs, *bs1; 1954 QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1; 1955 int ret; 1956 QEMUFile *f; 1957 int saved_vm_running; 1958 uint64_t vm_state_size; 1959 qemu_timeval tv; 1960 struct tm tm; 1961 const char *name = qdict_get_try_str(qdict, "name"); 1962 Error *local_err = NULL; 1963 AioContext *aio_context; 1964 1965 if (!bdrv_all_can_snapshot(&bs)) { 1966 monitor_printf(mon, "Device '%s' is writable but does not " 1967 "support snapshots.\n", bdrv_get_device_name(bs)); 1968 return; 1969 } 1970 1971 /* Delete old snapshots of the same name */ 1972 if (name && bdrv_all_delete_snapshot(name, &bs1, &local_err) < 0) { 1973 error_reportf_err(local_err, 1974 "Error while deleting snapshot on device '%s': ", 1975 bdrv_get_device_name(bs1)); 1976 return; 1977 } 1978 1979 bs = bdrv_all_find_vmstate_bs(); 1980 if (bs == NULL) { 1981 monitor_printf(mon, "No block device can accept snapshots\n"); 1982 return; 1983 } 1984 aio_context = bdrv_get_aio_context(bs); 1985 1986 saved_vm_running = runstate_is_running(); 1987 1988 ret = global_state_store(); 1989 if (ret) { 1990 monitor_printf(mon, "Error saving global state\n"); 1991 return; 1992 } 1993 vm_stop(RUN_STATE_SAVE_VM); 1994 1995 aio_context_acquire(aio_context); 1996 1997 memset(sn, 0, sizeof(*sn)); 1998 1999 /* fill auxiliary fields */ 2000 qemu_gettimeofday(&tv); 2001 sn->date_sec = tv.tv_sec; 2002 sn->date_nsec = tv.tv_usec * 1000; 2003 sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 2004 2005 if (name) { 2006 ret = bdrv_snapshot_find(bs, old_sn, name); 2007 if (ret >= 0) { 2008 pstrcpy(sn->name, sizeof(sn->name), old_sn->name); 2009 pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str); 2010 } else { 2011 pstrcpy(sn->name, sizeof(sn->name), name); 2012 } 2013 } else { 2014 /* cast below needed for OpenBSD where tv_sec is still 'long' */ 2015 localtime_r((const time_t *)&tv.tv_sec, &tm); 2016 strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm); 2017 } 2018 2019 /* save the VM state */ 2020 f = qemu_fopen_bdrv(bs, 1); 2021 if (!f) { 2022 monitor_printf(mon, "Could not open VM state file\n"); 2023 goto the_end; 2024 } 2025 ret = qemu_savevm_state(f, &local_err); 2026 vm_state_size = qemu_ftell(f); 2027 qemu_fclose(f); 2028 if (ret < 0) { 2029 error_report_err(local_err); 2030 goto the_end; 2031 } 2032 2033 ret = bdrv_all_create_snapshot(sn, bs, vm_state_size, &bs); 2034 if (ret < 0) { 2035 monitor_printf(mon, "Error while creating snapshot on '%s'\n", 2036 bdrv_get_device_name(bs)); 2037 } 2038 2039 the_end: 2040 aio_context_release(aio_context); 2041 if (saved_vm_running) { 2042 vm_start(); 2043 } 2044 } 2045 2046 void qmp_xen_save_devices_state(const char *filename, Error **errp) 2047 { 2048 QEMUFile *f; 2049 QIOChannelFile *ioc; 2050 int saved_vm_running; 2051 int ret; 2052 2053 saved_vm_running = runstate_is_running(); 2054 vm_stop(RUN_STATE_SAVE_VM); 2055 global_state_store_running(); 2056 2057 ioc = qio_channel_file_new_path(filename, O_WRONLY | O_CREAT, 0660, errp); 2058 if (!ioc) { 2059 goto the_end; 2060 } 2061 f = qemu_fopen_channel_output(QIO_CHANNEL(ioc)); 2062 ret = qemu_save_device_state(f); 2063 qemu_fclose(f); 2064 if (ret < 0) { 2065 error_setg(errp, QERR_IO_ERROR); 2066 } 2067 2068 the_end: 2069 if (saved_vm_running) { 2070 vm_start(); 2071 } 2072 } 2073 2074 void qmp_xen_load_devices_state(const char *filename, Error **errp) 2075 { 2076 QEMUFile *f; 2077 QIOChannelFile *ioc; 2078 int ret; 2079 2080 /* Guest must be paused before loading the device state; the RAM state 2081 * will already have been loaded by xc 2082 */ 2083 if (runstate_is_running()) { 2084 error_setg(errp, "Cannot update device state while vm is running"); 2085 return; 2086 } 2087 vm_stop(RUN_STATE_RESTORE_VM); 2088 2089 ioc = qio_channel_file_new_path(filename, O_RDONLY | O_BINARY, 0, errp); 2090 if (!ioc) { 2091 return; 2092 } 2093 f = qemu_fopen_channel_input(QIO_CHANNEL(ioc)); 2094 2095 migration_incoming_state_new(f); 2096 ret = qemu_loadvm_state(f); 2097 qemu_fclose(f); 2098 if (ret < 0) { 2099 error_setg(errp, QERR_IO_ERROR); 2100 } 2101 migration_incoming_state_destroy(); 2102 } 2103 2104 int load_vmstate(const char *name) 2105 { 2106 BlockDriverState *bs, *bs_vm_state; 2107 QEMUSnapshotInfo sn; 2108 QEMUFile *f; 2109 int ret; 2110 AioContext *aio_context; 2111 2112 if (!bdrv_all_can_snapshot(&bs)) { 2113 error_report("Device '%s' is writable but does not support snapshots.", 2114 bdrv_get_device_name(bs)); 2115 return -ENOTSUP; 2116 } 2117 ret = bdrv_all_find_snapshot(name, &bs); 2118 if (ret < 0) { 2119 error_report("Device '%s' does not have the requested snapshot '%s'", 2120 bdrv_get_device_name(bs), name); 2121 return ret; 2122 } 2123 2124 bs_vm_state = bdrv_all_find_vmstate_bs(); 2125 if (!bs_vm_state) { 2126 error_report("No block device supports snapshots"); 2127 return -ENOTSUP; 2128 } 2129 aio_context = bdrv_get_aio_context(bs_vm_state); 2130 2131 /* Don't even try to load empty VM states */ 2132 aio_context_acquire(aio_context); 2133 ret = bdrv_snapshot_find(bs_vm_state, &sn, name); 2134 aio_context_release(aio_context); 2135 if (ret < 0) { 2136 return ret; 2137 } else if (sn.vm_state_size == 0) { 2138 error_report("This is a disk-only snapshot. Revert to it offline " 2139 "using qemu-img."); 2140 return -EINVAL; 2141 } 2142 2143 /* Flush all IO requests so they don't interfere with the new state. */ 2144 bdrv_drain_all(); 2145 2146 ret = bdrv_all_goto_snapshot(name, &bs); 2147 if (ret < 0) { 2148 error_report("Error %d while activating snapshot '%s' on '%s'", 2149 ret, name, bdrv_get_device_name(bs)); 2150 return ret; 2151 } 2152 2153 /* restore the VM state */ 2154 f = qemu_fopen_bdrv(bs_vm_state, 0); 2155 if (!f) { 2156 error_report("Could not open VM state file"); 2157 return -EINVAL; 2158 } 2159 2160 qemu_system_reset(VMRESET_SILENT); 2161 migration_incoming_state_new(f); 2162 2163 aio_context_acquire(aio_context); 2164 ret = qemu_loadvm_state(f); 2165 qemu_fclose(f); 2166 aio_context_release(aio_context); 2167 2168 migration_incoming_state_destroy(); 2169 if (ret < 0) { 2170 error_report("Error %d while loading VM state", ret); 2171 return ret; 2172 } 2173 2174 return 0; 2175 } 2176 2177 void hmp_delvm(Monitor *mon, const QDict *qdict) 2178 { 2179 BlockDriverState *bs; 2180 Error *err; 2181 const char *name = qdict_get_str(qdict, "name"); 2182 2183 if (bdrv_all_delete_snapshot(name, &bs, &err) < 0) { 2184 error_reportf_err(err, 2185 "Error while deleting snapshot on device '%s': ", 2186 bdrv_get_device_name(bs)); 2187 } 2188 } 2189 2190 void hmp_info_snapshots(Monitor *mon, const QDict *qdict) 2191 { 2192 BlockDriverState *bs, *bs1; 2193 QEMUSnapshotInfo *sn_tab, *sn; 2194 int nb_sns, i; 2195 int total; 2196 int *available_snapshots; 2197 AioContext *aio_context; 2198 2199 bs = bdrv_all_find_vmstate_bs(); 2200 if (!bs) { 2201 monitor_printf(mon, "No available block device supports snapshots\n"); 2202 return; 2203 } 2204 aio_context = bdrv_get_aio_context(bs); 2205 2206 aio_context_acquire(aio_context); 2207 nb_sns = bdrv_snapshot_list(bs, &sn_tab); 2208 aio_context_release(aio_context); 2209 2210 if (nb_sns < 0) { 2211 monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns); 2212 return; 2213 } 2214 2215 if (nb_sns == 0) { 2216 monitor_printf(mon, "There is no snapshot available.\n"); 2217 return; 2218 } 2219 2220 available_snapshots = g_new0(int, nb_sns); 2221 total = 0; 2222 for (i = 0; i < nb_sns; i++) { 2223 if (bdrv_all_find_snapshot(sn_tab[i].id_str, &bs1) == 0) { 2224 available_snapshots[total] = i; 2225 total++; 2226 } 2227 } 2228 2229 if (total > 0) { 2230 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL); 2231 monitor_printf(mon, "\n"); 2232 for (i = 0; i < total; i++) { 2233 sn = &sn_tab[available_snapshots[i]]; 2234 bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn); 2235 monitor_printf(mon, "\n"); 2236 } 2237 } else { 2238 monitor_printf(mon, "There is no suitable snapshot available\n"); 2239 } 2240 2241 g_free(sn_tab); 2242 g_free(available_snapshots); 2243 2244 } 2245 2246 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev) 2247 { 2248 qemu_ram_set_idstr(mr->ram_block, 2249 memory_region_name(mr), dev); 2250 } 2251 2252 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev) 2253 { 2254 qemu_ram_unset_idstr(mr->ram_block); 2255 } 2256 2257 void vmstate_register_ram_global(MemoryRegion *mr) 2258 { 2259 vmstate_register_ram(mr, NULL); 2260 } 2261