savevm.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "config-host.h"
  26 #include "qemu-common.h"
  27 #include "hw/boards.h"
  28 #include "hw/hw.h"
  29 #include "hw/qdev.h"
  30 #include "net/net.h"
  31 #include "monitor/monitor.h"
  32 #include "sysemu/sysemu.h"
  33 #include "qemu/timer.h"
  34 #include "audio/audio.h"
  35 #include "migration/migration.h"
  36 #include "qemu/sockets.h"
  37 #include "qemu/queue.h"
  38 #include "sysemu/cpus.h"
  39 #include "exec/memory.h"
  40 #include "qmp-commands.h"
  41 #include "trace.h"
  42 #include "qemu/iov.h"
  43 #include "block/snapshot.h"
  44 #include "block/qapi.h"
  45
  46
  47 #ifndef ETH_P_RARP
  48 #define ETH_P_RARP 0x8035
  49 #endif
  50 #define ARP_HTYPE_ETH 0x0001
  51 #define ARP_PTYPE_IP 0x0800
  52 #define ARP_OP_REQUEST_REV 0x3
  53
  54 static int announce_self_create(uint8_t *buf,
  55                                 uint8_t *mac_addr)
  56 {
  57     /* Ethernet header. */
  58     memset(buf, 0xff, 6);         /* destination MAC addr */
  59     memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
  60     *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */
  61
  62     /* RARP header. */
  63     *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
  64     *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
  65     *(buf + 18) = 6; /* hardware addr length (ethernet) */
  66     *(buf + 19) = 4; /* protocol addr length (IPv4) */
  67     *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
  68     memcpy(buf + 22, mac_addr, 6); /* source hw addr */
  69     memset(buf + 28, 0x00, 4);     /* source protocol addr */
  70     memcpy(buf + 32, mac_addr, 6); /* target hw addr */
  71     memset(buf + 38, 0x00, 4);     /* target protocol addr */
  72
  73     /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
  74     memset(buf + 42, 0x00, 18);
  75
  76     return 60; /* len (FCS will be added by hardware) */
  77 }
  78
  79 static void qemu_announce_self_iter(NICState *nic, void *opaque)
  80 {
  81     uint8_t buf[60];
  82     int len;
  83
  84     trace_qemu_announce_self_iter(qemu_ether_ntoa(&nic->conf->macaddr));
  85     len = announce_self_create(buf, nic->conf->macaddr.a);
  86
  87     qemu_send_packet_raw(qemu_get_queue(nic), buf, len);
  88 }
  89
  90
  91 static void qemu_announce_self_once(void *opaque)
  92 {
  93     static int count = SELF_ANNOUNCE_ROUNDS;
  94     QEMUTimer *timer = *(QEMUTimer **)opaque;
  95
  96     qemu_foreach_nic(qemu_announce_self_iter, NULL);
  97
  98     if (--count) {
  99         /* delay 50ms, 150ms, 250ms, ... */
 100         timer_mod(timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) +
 101                   self_announce_delay(count));
 102     } else {
 103             timer_del(timer);
 104             timer_free(timer);
 105     }
 106 }
 107
 108 void qemu_announce_self(void)
 109 {
 110     static QEMUTimer *timer;
 111     timer = timer_new_ms(QEMU_CLOCK_REALTIME, qemu_announce_self_once, &timer);
 112     qemu_announce_self_once(&timer);
 113 }
 114
 115 /***********************************************************/
 116 /* savevm/loadvm support */
 117
 118 static ssize_t block_writev_buffer(void *opaque, struct iovec *iov, int iovcnt,
 119                                    int64_t pos)
 120 {
 121     int ret;
 122     QEMUIOVector qiov;
 123
 124     qemu_iovec_init_external(&qiov, iov, iovcnt);
 125     ret = bdrv_writev_vmstate(opaque, &qiov, pos);
 126     if (ret < 0) {
 127         return ret;
 128     }
 129
 130     return qiov.size;
 131 }
 132
 133 static int block_put_buffer(void *opaque, const uint8_t *buf,
 134                            int64_t pos, int size)
 135 {
 136     bdrv_save_vmstate(opaque, buf, pos, size);
 137     return size;
 138 }
 139
 140 static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 141 {
 142     return bdrv_load_vmstate(opaque, buf, pos, size);
 143 }
 144
 145 static int bdrv_fclose(void *opaque)
 146 {
 147     return bdrv_flush(opaque);
 148 }
 149
 150 static const QEMUFileOps bdrv_read_ops = {
 151     .get_buffer = block_get_buffer,
 152     .close =      bdrv_fclose
 153 };
 154
 155 static const QEMUFileOps bdrv_write_ops = {
 156     .put_buffer     = block_put_buffer,
 157     .writev_buffer  = block_writev_buffer,
 158     .close          = bdrv_fclose
 159 };
 160
 161 static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
 162 {
 163     if (is_writable) {
 164         return qemu_fopen_ops(bs, &bdrv_write_ops);
 165     }
 166     return qemu_fopen_ops(bs, &bdrv_read_ops);
 167 }
 168
 169
 170 /* QEMUFile timer support.
 171  * Not in qemu-file.c to not add qemu-timer.c as dependency to qemu-file.c
 172  */
 173
 174 void timer_put(QEMUFile *f, QEMUTimer *ts)
 175 {
 176     uint64_t expire_time;
 177
 178     expire_time = timer_expire_time_ns(ts);
 179     qemu_put_be64(f, expire_time);
 180 }
 181
 182 void timer_get(QEMUFile *f, QEMUTimer *ts)
 183 {
 184     uint64_t expire_time;
 185
 186     expire_time = qemu_get_be64(f);
 187     if (expire_time != -1) {
 188         timer_mod_ns(ts, expire_time);
 189     } else {
 190         timer_del(ts);
 191     }
 192 }
 193
 194
 195 /* VMState timer support.
 196  * Not in vmstate.c to not add qemu-timer.c as dependency to vmstate.c
 197  */
 198
 199 static int get_timer(QEMUFile *f, void *pv, size_t size)
 200 {
 201     QEMUTimer *v = pv;
 202     timer_get(f, v);
 203     return 0;
 204 }
 205
 206 static void put_timer(QEMUFile *f, void *pv, size_t size)
 207 {
 208     QEMUTimer *v = pv;
 209     timer_put(f, v);
 210 }
 211
 212 const VMStateInfo vmstate_info_timer = {
 213     .name = "timer",
 214     .get  = get_timer,
 215     .put  = put_timer,
 216 };
 217
 218
 219 typedef struct CompatEntry {
 220     char idstr[256];
 221     int instance_id;
 222 } CompatEntry;
 223
 224 typedef struct SaveStateEntry {
 225     QTAILQ_ENTRY(SaveStateEntry) entry;
 226     char idstr[256];
 227     int instance_id;
 228     int alias_id;
 229     int version_id;
 230     int section_id;
 231     SaveVMHandlers *ops;
 232     const VMStateDescription *vmsd;
 233     void *opaque;
 234     CompatEntry *compat;
 235     int is_ram;
 236 } SaveStateEntry;
 237
 238
 239 static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
 240     QTAILQ_HEAD_INITIALIZER(savevm_handlers);
 241 static int global_section_id;
 242
 243 static void dump_vmstate_vmsd(FILE *out_file,
 244                               const VMStateDescription *vmsd, int indent,
 245                               bool is_subsection);
 246
 247 static void dump_vmstate_vmsf(FILE *out_file, const VMStateField *field,
 248                               int indent)
 249 {
 250     fprintf(out_file, "%*s{\n", indent, "");
 251     indent += 2;
 252     fprintf(out_file, "%*s\"field\": \"%s\",\n", indent, "", field->name);
 253     fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "",
 254             field->version_id);
 255     fprintf(out_file, "%*s\"field_exists\": %s,\n", indent, "",
 256             field->field_exists ? "true" : "false");
 257     fprintf(out_file, "%*s\"size\": %zu", indent, "", field->size);
 258     if (field->vmsd != NULL) {
 259         fprintf(out_file, ",\n");
 260         dump_vmstate_vmsd(out_file, field->vmsd, indent, false);
 261     }
 262     fprintf(out_file, "\n%*s}", indent - 2, "");
 263 }
 264
 265 static void dump_vmstate_vmss(FILE *out_file,
 266                               const VMStateSubsection *subsection,
 267                               int indent)
 268 {
 269     if (subsection->vmsd != NULL) {
 270         dump_vmstate_vmsd(out_file, subsection->vmsd, indent, true);
 271     }
 272 }
 273
 274 static void dump_vmstate_vmsd(FILE *out_file,
 275                               const VMStateDescription *vmsd, int indent,
 276                               bool is_subsection)
 277 {
 278     if (is_subsection) {
 279         fprintf(out_file, "%*s{\n", indent, "");
 280     } else {
 281         fprintf(out_file, "%*s\"%s\": {\n", indent, "", "Description");
 282     }
 283     indent += 2;
 284     fprintf(out_file, "%*s\"name\": \"%s\",\n", indent, "", vmsd->name);
 285     fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "",
 286             vmsd->version_id);
 287     fprintf(out_file, "%*s\"minimum_version_id\": %d", indent, "",
 288             vmsd->minimum_version_id);
 289     if (vmsd->fields != NULL) {
 290         const VMStateField *field = vmsd->fields;
 291         bool first;
 292
 293         fprintf(out_file, ",\n%*s\"Fields\": [\n", indent, "");
 294         first = true;
 295         while (field->name != NULL) {
 296             if (field->flags & VMS_MUST_EXIST) {
 297                 /* Ignore VMSTATE_VALIDATE bits; these don't get migrated */
 298                 field++;
 299                 continue;
 300             }
 301             if (!first) {
 302                 fprintf(out_file, ",\n");
 303             }
 304             dump_vmstate_vmsf(out_file, field, indent + 2);
 305             field++;
 306             first = false;
 307         }
 308         fprintf(out_file, "\n%*s]", indent, "");
 309     }
 310     if (vmsd->subsections != NULL) {
 311         const VMStateSubsection *subsection = vmsd->subsections;
 312         bool first;
 313
 314         fprintf(out_file, ",\n%*s\"Subsections\": [\n", indent, "");
 315         first = true;
 316         while (subsection->vmsd != NULL) {
 317             if (!first) {
 318                 fprintf(out_file, ",\n");
 319             }
 320             dump_vmstate_vmss(out_file, subsection, indent + 2);
 321             subsection++;
 322             first = false;
 323         }
 324         fprintf(out_file, "\n%*s]", indent, "");
 325     }
 326     fprintf(out_file, "\n%*s}", indent - 2, "");
 327 }
 328
 329 static void dump_machine_type(FILE *out_file)
 330 {
 331     MachineClass *mc;
 332
 333     mc = MACHINE_GET_CLASS(current_machine);
 334
 335     fprintf(out_file, "  \"vmschkmachine\": {\n");
 336     fprintf(out_file, "    \"Name\": \"%s\"\n", mc->name);
 337     fprintf(out_file, "  },\n");
 338 }
 339
 340 void dump_vmstate_json_to_file(FILE *out_file)
 341 {
 342     GSList *list, *elt;
 343     bool first;
 344
 345     fprintf(out_file, "{\n");
 346     dump_machine_type(out_file);
 347
 348     first = true;
 349     list = object_class_get_list(TYPE_DEVICE, true);
 350     for (elt = list; elt; elt = elt->next) {
 351         DeviceClass *dc = OBJECT_CLASS_CHECK(DeviceClass, elt->data,
 352                                              TYPE_DEVICE);
 353         const char *name;
 354         int indent = 2;
 355
 356         if (!dc->vmsd) {
 357             continue;
 358         }
 359
 360         if (!first) {
 361             fprintf(out_file, ",\n");
 362         }
 363         name = object_class_get_name(OBJECT_CLASS(dc));
 364         fprintf(out_file, "%*s\"%s\": {\n", indent, "", name);
 365         indent += 2;
 366         fprintf(out_file, "%*s\"Name\": \"%s\",\n", indent, "", name);
 367         fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "",
 368                 dc->vmsd->version_id);
 369         fprintf(out_file, "%*s\"minimum_version_id\": %d,\n", indent, "",
 370                 dc->vmsd->minimum_version_id);
 371
 372         dump_vmstate_vmsd(out_file, dc->vmsd, indent, false);
 373
 374         fprintf(out_file, "\n%*s}", indent - 2, "");
 375         first = false;
 376     }
 377     fprintf(out_file, "\n}\n");
 378     fclose(out_file);
 379 }
 380
 381 static int calculate_new_instance_id(const char *idstr)
 382 {
 383     SaveStateEntry *se;
 384     int instance_id = 0;
 385
 386     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 387         if (strcmp(idstr, se->idstr) == 0
 388             && instance_id <= se->instance_id) {
 389             instance_id = se->instance_id + 1;
 390         }
 391     }
 392     return instance_id;
 393 }
 394
 395 static int calculate_compat_instance_id(const char *idstr)
 396 {
 397     SaveStateEntry *se;
 398     int instance_id = 0;
 399
 400     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 401         if (!se->compat) {
 402             continue;
 403         }
 404
 405         if (strcmp(idstr, se->compat->idstr) == 0
 406             && instance_id <= se->compat->instance_id) {
 407             instance_id = se->compat->instance_id + 1;
 408         }
 409     }
 410     return instance_id;
 411 }
 412
 413 /* TODO: Individual devices generally have very little idea about the rest
 414    of the system, so instance_id should be removed/replaced.
 415    Meanwhile pass -1 as instance_id if you do not already have a clearly
 416    distinguishing id for all instances of your device class. */
 417 int register_savevm_live(DeviceState *dev,
 418                          const char *idstr,
 419                          int instance_id,
 420                          int version_id,
 421                          SaveVMHandlers *ops,
 422                          void *opaque)
 423 {
 424     SaveStateEntry *se;
 425
 426     se = g_malloc0(sizeof(SaveStateEntry));
 427     se->version_id = version_id;
 428     se->section_id = global_section_id++;
 429     se->ops = ops;
 430     se->opaque = opaque;
 431     se->vmsd = NULL;
 432     /* if this is a live_savem then set is_ram */
 433     if (ops->save_live_setup != NULL) {
 434         se->is_ram = 1;
 435     }
 436
 437     if (dev) {
 438         char *id = qdev_get_dev_path(dev);
 439         if (id) {
 440             pstrcpy(se->idstr, sizeof(se->idstr), id);
 441             pstrcat(se->idstr, sizeof(se->idstr), "/");
 442             g_free(id);
 443
 444             se->compat = g_malloc0(sizeof(CompatEntry));
 445             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
 446             se->compat->instance_id = instance_id == -1 ?
 447                          calculate_compat_instance_id(idstr) : instance_id;
 448             instance_id = -1;
 449         }
 450     }
 451     pstrcat(se->idstr, sizeof(se->idstr), idstr);
 452
 453     if (instance_id == -1) {
 454         se->instance_id = calculate_new_instance_id(se->idstr);
 455     } else {
 456         se->instance_id = instance_id;
 457     }
 458     assert(!se->compat || se->instance_id == 0);
 459     /* add at the end of list */
 460     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
 461     return 0;
 462 }
 463
 464 int register_savevm(DeviceState *dev,
 465                     const char *idstr,
 466                     int instance_id,
 467                     int version_id,
 468                     SaveStateHandler *save_state,
 469                     LoadStateHandler *load_state,
 470                     void *opaque)
 471 {
 472     SaveVMHandlers *ops = g_malloc0(sizeof(SaveVMHandlers));
 473     ops->save_state = save_state;
 474     ops->load_state = load_state;
 475     return register_savevm_live(dev, idstr, instance_id, version_id,
 476                                 ops, opaque);
 477 }
 478
 479 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
 480 {
 481     SaveStateEntry *se, *new_se;
 482     char id[256] = "";
 483
 484     if (dev) {
 485         char *path = qdev_get_dev_path(dev);
 486         if (path) {
 487             pstrcpy(id, sizeof(id), path);
 488             pstrcat(id, sizeof(id), "/");
 489             g_free(path);
 490         }
 491     }
 492     pstrcat(id, sizeof(id), idstr);
 493
 494     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
 495         if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
 496             QTAILQ_REMOVE(&savevm_handlers, se, entry);
 497             if (se->compat) {
 498                 g_free(se->compat);
 499             }
 500             g_free(se->ops);
 501             g_free(se);
 502         }
 503     }
 504 }
 505
 506 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
 507                                    const VMStateDescription *vmsd,
 508                                    void *opaque, int alias_id,
 509                                    int required_for_version)
 510 {
 511     SaveStateEntry *se;
 512
 513     /* If this triggers, alias support can be dropped for the vmsd. */
 514     assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);
 515
 516     se = g_malloc0(sizeof(SaveStateEntry));
 517     se->version_id = vmsd->version_id;
 518     se->section_id = global_section_id++;
 519     se->opaque = opaque;
 520     se->vmsd = vmsd;
 521     se->alias_id = alias_id;
 522
 523     if (dev) {
 524         char *id = qdev_get_dev_path(dev);
 525         if (id) {
 526             pstrcpy(se->idstr, sizeof(se->idstr), id);
 527             pstrcat(se->idstr, sizeof(se->idstr), "/");
 528             g_free(id);
 529
 530             se->compat = g_malloc0(sizeof(CompatEntry));
 531             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
 532             se->compat->instance_id = instance_id == -1 ?
 533                          calculate_compat_instance_id(vmsd->name) : instance_id;
 534             instance_id = -1;
 535         }
 536     }
 537     pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
 538
 539     if (instance_id == -1) {
 540         se->instance_id = calculate_new_instance_id(se->idstr);
 541     } else {
 542         se->instance_id = instance_id;
 543     }
 544     assert(!se->compat || se->instance_id == 0);
 545     /* add at the end of list */
 546     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
 547     return 0;
 548 }
 549
 550 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
 551                         void *opaque)
 552 {
 553     SaveStateEntry *se, *new_se;
 554
 555     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
 556         if (se->vmsd == vmsd && se->opaque == opaque) {
 557             QTAILQ_REMOVE(&savevm_handlers, se, entry);
 558             if (se->compat) {
 559                 g_free(se->compat);
 560             }
 561             g_free(se);
 562         }
 563     }
 564 }
 565
 566 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
 567 {
 568     trace_vmstate_load(se->idstr, se->vmsd ? se->vmsd->name : "(old)");
 569     if (!se->vmsd) {         /* Old style */
 570         return se->ops->load_state(f, se->opaque, version_id);
 571     }
 572     return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
 573 }
 574
 575 static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc)
 576 {
 577     int64_t old_offset, size;
 578
 579     old_offset = qemu_ftell_fast(f);
 580     se->ops->save_state(f, se->opaque);
 581     size = qemu_ftell_fast(f) - old_offset;
 582
 583     if (vmdesc) {
 584         json_prop_int(vmdesc, "size", size);
 585         json_start_array(vmdesc, "fields");
 586         json_start_object(vmdesc, NULL);
 587         json_prop_str(vmdesc, "name", "data");
 588         json_prop_int(vmdesc, "size", size);
 589         json_prop_str(vmdesc, "type", "buffer");
 590         json_end_object(vmdesc);
 591         json_end_array(vmdesc);
 592     }
 593 }
 594
 595 static void vmstate_save(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc)
 596 {
 597     trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)");
 598     if (!se->vmsd) {
 599         vmstate_save_old_style(f, se, vmdesc);
 600         return;
 601     }
 602     vmstate_save_state(f, se->vmsd, se->opaque, vmdesc);
 603 }
 604
 605 bool qemu_savevm_state_blocked(Error **errp)
 606 {
 607     SaveStateEntry *se;
 608
 609     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 610         if (se->vmsd && se->vmsd->unmigratable) {
 611             error_setg(errp, "State blocked by non-migratable device '%s'",
 612                        se->idstr);
 613             return true;
 614         }
 615     }
 616     return false;
 617 }
 618
 619 void qemu_savevm_state_begin(QEMUFile *f,
 620                              const MigrationParams *params)
 621 {
 622     SaveStateEntry *se;
 623     int ret;
 624
 625     trace_savevm_state_begin();
 626     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 627         if (!se->ops || !se->ops->set_params) {
 628             continue;
 629         }
 630         se->ops->set_params(params, se->opaque);
 631     }
 632
 633     qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
 634     qemu_put_be32(f, QEMU_VM_FILE_VERSION);
 635
 636     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 637         int len;
 638
 639         if (!se->ops || !se->ops->save_live_setup) {
 640             continue;
 641         }
 642         if (se->ops && se->ops->is_active) {
 643             if (!se->ops->is_active(se->opaque)) {
 644                 continue;
 645             }
 646         }
 647         /* Section type */
 648         qemu_put_byte(f, QEMU_VM_SECTION_START);
 649         qemu_put_be32(f, se->section_id);
 650
 651         /* ID string */
 652         len = strlen(se->idstr);
 653         qemu_put_byte(f, len);
 654         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
 655
 656         qemu_put_be32(f, se->instance_id);
 657         qemu_put_be32(f, se->version_id);
 658
 659         ret = se->ops->save_live_setup(f, se->opaque);
 660         if (ret < 0) {
 661             qemu_file_set_error(f, ret);
 662             break;
 663         }
 664     }
 665 }
 666
 667 /*
 668  * this function has three return values:
 669  *   negative: there was one error, and we have -errno.
 670  *   0 : We haven't finished, caller have to go again
 671  *   1 : We have finished, we can go to complete phase
 672  */
 673 int qemu_savevm_state_iterate(QEMUFile *f)
 674 {
 675     SaveStateEntry *se;
 676     int ret = 1;
 677
 678     trace_savevm_state_iterate();
 679     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 680         if (!se->ops || !se->ops->save_live_iterate) {
 681             continue;
 682         }
 683         if (se->ops && se->ops->is_active) {
 684             if (!se->ops->is_active(se->opaque)) {
 685                 continue;
 686             }
 687         }
 688         if (qemu_file_rate_limit(f)) {
 689             return 0;
 690         }
 691         trace_savevm_section_start(se->idstr, se->section_id);
 692         /* Section type */
 693         qemu_put_byte(f, QEMU_VM_SECTION_PART);
 694         qemu_put_be32(f, se->section_id);
 695
 696         ret = se->ops->save_live_iterate(f, se->opaque);
 697         trace_savevm_section_end(se->idstr, se->section_id, ret);
 698
 699         if (ret < 0) {
 700             qemu_file_set_error(f, ret);
 701         }
 702         if (ret <= 0) {
 703             /* Do not proceed to the next vmstate before this one reported
 704                completion of the current stage. This serializes the migration
 705                and reduces the probability that a faster changing state is
 706                synchronized over and over again. */
 707             break;
 708         }
 709     }
 710     return ret;
 711 }
 712
 713 void qemu_savevm_state_complete(QEMUFile *f)
 714 {
 715     QJSON *vmdesc;
 716     int vmdesc_len;
 717     SaveStateEntry *se;
 718     int ret;
 719
 720     trace_savevm_state_complete();
 721
 722     cpu_synchronize_all_states();
 723
 724     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 725         if (!se->ops || !se->ops->save_live_complete) {
 726             continue;
 727         }
 728         if (se->ops && se->ops->is_active) {
 729             if (!se->ops->is_active(se->opaque)) {
 730                 continue;
 731             }
 732         }
 733         trace_savevm_section_start(se->idstr, se->section_id);
 734         /* Section type */
 735         qemu_put_byte(f, QEMU_VM_SECTION_END);
 736         qemu_put_be32(f, se->section_id);
 737
 738         ret = se->ops->save_live_complete(f, se->opaque);
 739         trace_savevm_section_end(se->idstr, se->section_id, ret);
 740         if (ret < 0) {
 741             qemu_file_set_error(f, ret);
 742             return;
 743         }
 744     }
 745
 746     vmdesc = qjson_new();
 747     json_prop_int(vmdesc, "page_size", TARGET_PAGE_SIZE);
 748     json_start_array(vmdesc, "devices");
 749     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 750         int len;
 751
 752         if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
 753             continue;
 754         }
 755         trace_savevm_section_start(se->idstr, se->section_id);
 756
 757         json_start_object(vmdesc, NULL);
 758         json_prop_str(vmdesc, "name", se->idstr);
 759         json_prop_int(vmdesc, "instance_id", se->instance_id);
 760
 761         /* Section type */
 762         qemu_put_byte(f, QEMU_VM_SECTION_FULL);
 763         qemu_put_be32(f, se->section_id);
 764
 765         /* ID string */
 766         len = strlen(se->idstr);
 767         qemu_put_byte(f, len);
 768         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
 769
 770         qemu_put_be32(f, se->instance_id);
 771         qemu_put_be32(f, se->version_id);
 772
 773         vmstate_save(f, se, vmdesc);
 774
 775         json_end_object(vmdesc);
 776         trace_savevm_section_end(se->idstr, se->section_id, 0);
 777     }
 778
 779     qemu_put_byte(f, QEMU_VM_EOF);
 780
 781     json_end_array(vmdesc);
 782     qjson_finish(vmdesc);
 783     vmdesc_len = strlen(qjson_get_str(vmdesc));
 784
 785     qemu_put_byte(f, QEMU_VM_VMDESCRIPTION);
 786     qemu_put_be32(f, vmdesc_len);
 787     qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len);
 788     object_unref(OBJECT(vmdesc));
 789
 790     qemu_fflush(f);
 791 }
 792
 793 uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size)
 794 {
 795     SaveStateEntry *se;
 796     uint64_t ret = 0;
 797
 798     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 799         if (!se->ops || !se->ops->save_live_pending) {
 800             continue;
 801         }
 802         if (se->ops && se->ops->is_active) {
 803             if (!se->ops->is_active(se->opaque)) {
 804                 continue;
 805             }
 806         }
 807         ret += se->ops->save_live_pending(f, se->opaque, max_size);
 808     }
 809     return ret;
 810 }
 811
 812 void qemu_savevm_state_cancel(void)
 813 {
 814     SaveStateEntry *se;
 815
 816     trace_savevm_state_cancel();
 817     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 818         if (se->ops && se->ops->cancel) {
 819             se->ops->cancel(se->opaque);
 820         }
 821     }
 822 }
 823
 824 static int qemu_savevm_state(QEMUFile *f, Error **errp)
 825 {
 826     int ret;
 827     MigrationParams params = {
 828         .blk = 0,
 829         .shared = 0
 830     };
 831
 832     if (qemu_savevm_state_blocked(errp)) {
 833         return -EINVAL;
 834     }
 835
 836     qemu_mutex_unlock_iothread();
 837     qemu_savevm_state_begin(f, &params);
 838     qemu_mutex_lock_iothread();
 839
 840     while (qemu_file_get_error(f) == 0) {
 841         if (qemu_savevm_state_iterate(f) > 0) {
 842             break;
 843         }
 844     }
 845
 846     ret = qemu_file_get_error(f);
 847     if (ret == 0) {
 848         qemu_savevm_state_complete(f);
 849         ret = qemu_file_get_error(f);
 850     }
 851     if (ret != 0) {
 852         qemu_savevm_state_cancel();
 853         error_setg_errno(errp, -ret, "Error while writing VM state");
 854     }
 855     return ret;
 856 }
 857
 858 static int qemu_save_device_state(QEMUFile *f)
 859 {
 860     SaveStateEntry *se;
 861
 862     qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
 863     qemu_put_be32(f, QEMU_VM_FILE_VERSION);
 864
 865     cpu_synchronize_all_states();
 866
 867     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 868         int len;
 869
 870         if (se->is_ram) {
 871             continue;
 872         }
 873         if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
 874             continue;
 875         }
 876
 877         /* Section type */
 878         qemu_put_byte(f, QEMU_VM_SECTION_FULL);
 879         qemu_put_be32(f, se->section_id);
 880
 881         /* ID string */
 882         len = strlen(se->idstr);
 883         qemu_put_byte(f, len);
 884         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
 885
 886         qemu_put_be32(f, se->instance_id);
 887         qemu_put_be32(f, se->version_id);
 888
 889         vmstate_save(f, se, NULL);
 890     }
 891
 892     qemu_put_byte(f, QEMU_VM_EOF);
 893
 894     return qemu_file_get_error(f);
 895 }
 896
 897 static SaveStateEntry *find_se(const char *idstr, int instance_id)
 898 {
 899     SaveStateEntry *se;
 900
 901     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 902         if (!strcmp(se->idstr, idstr) &&
 903             (instance_id == se->instance_id ||
 904              instance_id == se->alias_id))
 905             return se;
 906         /* Migrating from an older version? */
 907         if (strstr(se->idstr, idstr) && se->compat) {
 908             if (!strcmp(se->compat->idstr, idstr) &&
 909                 (instance_id == se->compat->instance_id ||
 910                  instance_id == se->alias_id))
 911                 return se;
 912         }
 913     }
 914     return NULL;
 915 }
 916
 917 typedef struct LoadStateEntry {
 918     QLIST_ENTRY(LoadStateEntry) entry;
 919     SaveStateEntry *se;
 920     int section_id;
 921     int version_id;
 922 } LoadStateEntry;
 923
 924 int qemu_loadvm_state(QEMUFile *f)
 925 {
 926     QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
 927         QLIST_HEAD_INITIALIZER(loadvm_handlers);
 928     LoadStateEntry *le, *new_le;
 929     Error *local_err = NULL;
 930     uint8_t section_type;
 931     unsigned int v;
 932     int ret;
 933
 934     if (qemu_savevm_state_blocked(&local_err)) {
 935         error_report("%s", error_get_pretty(local_err));
 936         error_free(local_err);
 937         return -EINVAL;
 938     }
 939
 940     v = qemu_get_be32(f);
 941     if (v != QEMU_VM_FILE_MAGIC) {
 942         error_report("Not a migration stream");
 943         return -EINVAL;
 944     }
 945
 946     v = qemu_get_be32(f);
 947     if (v == QEMU_VM_FILE_VERSION_COMPAT) {
 948         error_report("SaveVM v2 format is obsolete and don't work anymore");
 949         return -ENOTSUP;
 950     }
 951     if (v != QEMU_VM_FILE_VERSION) {
 952         error_report("Unsupported migration stream version");
 953         return -ENOTSUP;
 954     }
 955
 956     while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
 957         uint32_t instance_id, version_id, section_id;
 958         SaveStateEntry *se;
 959         char idstr[257];
 960         int len;
 961
 962         trace_qemu_loadvm_state_section(section_type);
 963         switch (section_type) {
 964         case QEMU_VM_SECTION_START:
 965         case QEMU_VM_SECTION_FULL:
 966             /* Read section start */
 967             section_id = qemu_get_be32(f);
 968             len = qemu_get_byte(f);
 969             qemu_get_buffer(f, (uint8_t *)idstr, len);
 970             idstr[len] = 0;
 971             instance_id = qemu_get_be32(f);
 972             version_id = qemu_get_be32(f);
 973
 974             trace_qemu_loadvm_state_section_startfull(section_id, idstr,
 975                                                       instance_id, version_id);
 976             /* Find savevm section */
 977             se = find_se(idstr, instance_id);
 978             if (se == NULL) {
 979                 error_report("Unknown savevm section or instance '%s' %d",
 980                              idstr, instance_id);
 981                 ret = -EINVAL;
 982                 goto out;
 983             }
 984
 985             /* Validate version */
 986             if (version_id > se->version_id) {
 987                 error_report("savevm: unsupported version %d for '%s' v%d",
 988                              version_id, idstr, se->version_id);
 989                 ret = -EINVAL;
 990                 goto out;
 991             }
 992
 993             /* Add entry */
 994             le = g_malloc0(sizeof(*le));
 995
 996             le->se = se;
 997             le->section_id = section_id;
 998             le->version_id = version_id;
 999             QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
1000
1001             ret = vmstate_load(f, le->se, le->version_id);
1002             if (ret < 0) {
1003                 error_report("error while loading state for instance 0x%x of"
1004                              " device '%s'", instance_id, idstr);
1005                 goto out;
1006             }
1007             break;
1008         case QEMU_VM_SECTION_PART:
1009         case QEMU_VM_SECTION_END:
1010             section_id = qemu_get_be32(f);
1011
1012             trace_qemu_loadvm_state_section_partend(section_id);
1013             QLIST_FOREACH(le, &loadvm_handlers, entry) {
1014                 if (le->section_id == section_id) {
1015                     break;
1016                 }
1017             }
1018             if (le == NULL) {
1019                 error_report("Unknown savevm section %d", section_id);
1020                 ret = -EINVAL;
1021                 goto out;
1022             }
1023
1024             ret = vmstate_load(f, le->se, le->version_id);
1025             if (ret < 0) {
1026                 error_report("error while loading state section id %d(%s)",
1027                              section_id, le->se->idstr);
1028                 goto out;
1029             }
1030             break;
1031         default:
1032             error_report("Unknown savevm section type %d", section_type);
1033             ret = -EINVAL;
1034             goto out;
1035         }
1036     }
1037
1038     cpu_synchronize_all_post_init();
1039
1040     ret = 0;
1041
1042 out:
1043     QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
1044         QLIST_REMOVE(le, entry);
1045         g_free(le);
1046     }
1047
1048     if (ret == 0) {
1049         ret = qemu_file_get_error(f);
1050     }
1051
1052     return ret;
1053 }
1054
1055 static BlockDriverState *find_vmstate_bs(void)
1056 {
1057     BlockDriverState *bs = NULL;
1058     while ((bs = bdrv_next(bs))) {
1059         if (bdrv_can_snapshot(bs)) {
1060             return bs;
1061         }
1062     }
1063     return NULL;
1064 }
1065
1066 /*
1067  * Deletes snapshots of a given name in all opened images.
1068  */
1069 static int del_existing_snapshots(Monitor *mon, const char *name)
1070 {
1071     BlockDriverState *bs;
1072     QEMUSnapshotInfo sn1, *snapshot = &sn1;
1073     Error *err = NULL;
1074
1075     bs = NULL;
1076     while ((bs = bdrv_next(bs))) {
1077         if (bdrv_can_snapshot(bs) &&
1078             bdrv_snapshot_find(bs, snapshot, name) >= 0) {
1079             bdrv_snapshot_delete_by_id_or_name(bs, name, &err);
1080             if (err) {
1081                 monitor_printf(mon,
1082                                "Error while deleting snapshot on device '%s':"
1083                                " %s\n",
1084                                bdrv_get_device_name(bs),
1085                                error_get_pretty(err));
1086                 error_free(err);
1087                 return -1;
1088             }
1089         }
1090     }
1091
1092     return 0;
1093 }
1094
1095 void hmp_savevm(Monitor *mon, const QDict *qdict)
1096 {
1097     BlockDriverState *bs, *bs1;
1098     QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
1099     int ret;
1100     QEMUFile *f;
1101     int saved_vm_running;
1102     uint64_t vm_state_size;
1103     qemu_timeval tv;
1104     struct tm tm;
1105     const char *name = qdict_get_try_str(qdict, "name");
1106     Error *local_err = NULL;
1107
1108     /* Verify if there is a device that doesn't support snapshots and is writable */
1109     bs = NULL;
1110     while ((bs = bdrv_next(bs))) {
1111
1112         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
1113             continue;
1114         }
1115
1116         if (!bdrv_can_snapshot(bs)) {
1117             monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
1118                                bdrv_get_device_name(bs));
1119             return;
1120         }
1121     }
1122
1123     bs = find_vmstate_bs();
1124     if (!bs) {
1125         monitor_printf(mon, "No block device can accept snapshots\n");
1126         return;
1127     }
1128
1129     saved_vm_running = runstate_is_running();
1130     vm_stop(RUN_STATE_SAVE_VM);
1131
1132     memset(sn, 0, sizeof(*sn));
1133
1134     /* fill auxiliary fields */
1135     qemu_gettimeofday(&tv);
1136     sn->date_sec = tv.tv_sec;
1137     sn->date_nsec = tv.tv_usec * 1000;
1138     sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
1139
1140     if (name) {
1141         ret = bdrv_snapshot_find(bs, old_sn, name);
1142         if (ret >= 0) {
1143             pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
1144             pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
1145         } else {
1146             pstrcpy(sn->name, sizeof(sn->name), name);
1147         }
1148     } else {
1149         /* cast below needed for OpenBSD where tv_sec is still 'long' */
1150         localtime_r((const time_t *)&tv.tv_sec, &tm);
1151         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
1152     }
1153
1154     /* Delete old snapshots of the same name */
1155     if (name && del_existing_snapshots(mon, name) < 0) {
1156         goto the_end;
1157     }
1158
1159     /* save the VM state */
1160     f = qemu_fopen_bdrv(bs, 1);
1161     if (!f) {
1162         monitor_printf(mon, "Could not open VM state file\n");
1163         goto the_end;
1164     }
1165     ret = qemu_savevm_state(f, &local_err);
1166     vm_state_size = qemu_ftell(f);
1167     qemu_fclose(f);
1168     if (ret < 0) {
1169         monitor_printf(mon, "%s\n", error_get_pretty(local_err));
1170         error_free(local_err);
1171         goto the_end;
1172     }
1173
1174     /* create the snapshots */
1175
1176     bs1 = NULL;
1177     while ((bs1 = bdrv_next(bs1))) {
1178         if (bdrv_can_snapshot(bs1)) {
1179             /* Write VM state size only to the image that contains the state */
1180             sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
1181             ret = bdrv_snapshot_create(bs1, sn);
1182             if (ret < 0) {
1183                 monitor_printf(mon, "Error while creating snapshot on '%s'\n",
1184                                bdrv_get_device_name(bs1));
1185             }
1186         }
1187     }
1188
1189  the_end:
1190     if (saved_vm_running) {
1191         vm_start();
1192     }
1193 }
1194
1195 void qmp_xen_save_devices_state(const char *filename, Error **errp)
1196 {
1197     QEMUFile *f;
1198     int saved_vm_running;
1199     int ret;
1200
1201     saved_vm_running = runstate_is_running();
1202     vm_stop(RUN_STATE_SAVE_VM);
1203
1204     f = qemu_fopen(filename, "wb");
1205     if (!f) {
1206         error_setg_file_open(errp, errno, filename);
1207         goto the_end;
1208     }
1209     ret = qemu_save_device_state(f);
1210     qemu_fclose(f);
1211     if (ret < 0) {
1212         error_set(errp, QERR_IO_ERROR);
1213     }
1214
1215  the_end:
1216     if (saved_vm_running) {
1217         vm_start();
1218     }
1219 }
1220
1221 int load_vmstate(const char *name)
1222 {
1223     BlockDriverState *bs, *bs_vm_state;
1224     QEMUSnapshotInfo sn;
1225     QEMUFile *f;
1226     int ret;
1227
1228     bs_vm_state = find_vmstate_bs();
1229     if (!bs_vm_state) {
1230         error_report("No block device supports snapshots");
1231         return -ENOTSUP;
1232     }
1233
1234     /* Don't even try to load empty VM states */
1235     ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
1236     if (ret < 0) {
1237         return ret;
1238     } else if (sn.vm_state_size == 0) {
1239         error_report("This is a disk-only snapshot. Revert to it offline "
1240             "using qemu-img.");
1241         return -EINVAL;
1242     }
1243
1244     /* Verify if there is any device that doesn't support snapshots and is
1245     writable and check if the requested snapshot is available too. */
1246     bs = NULL;
1247     while ((bs = bdrv_next(bs))) {
1248
1249         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
1250             continue;
1251         }
1252
1253         if (!bdrv_can_snapshot(bs)) {
1254             error_report("Device '%s' is writable but does not support snapshots.",
1255                                bdrv_get_device_name(bs));
1256             return -ENOTSUP;
1257         }
1258
1259         ret = bdrv_snapshot_find(bs, &sn, name);
1260         if (ret < 0) {
1261             error_report("Device '%s' does not have the requested snapshot '%s'",
1262                            bdrv_get_device_name(bs), name);
1263             return ret;
1264         }
1265     }
1266
1267     /* Flush all IO requests so they don't interfere with the new state.  */
1268     bdrv_drain_all();
1269
1270     bs = NULL;
1271     while ((bs = bdrv_next(bs))) {
1272         if (bdrv_can_snapshot(bs)) {
1273             ret = bdrv_snapshot_goto(bs, name);
1274             if (ret < 0) {
1275                 error_report("Error %d while activating snapshot '%s' on '%s'",
1276                              ret, name, bdrv_get_device_name(bs));
1277                 return ret;
1278             }
1279         }
1280     }
1281
1282     /* restore the VM state */
1283     f = qemu_fopen_bdrv(bs_vm_state, 0);
1284     if (!f) {
1285         error_report("Could not open VM state file");
1286         return -EINVAL;
1287     }
1288
1289     qemu_system_reset(VMRESET_SILENT);
1290     ret = qemu_loadvm_state(f);
1291
1292     qemu_fclose(f);
1293     if (ret < 0) {
1294         error_report("Error %d while loading VM state", ret);
1295         return ret;
1296     }
1297
1298     return 0;
1299 }
1300
1301 void hmp_delvm(Monitor *mon, const QDict *qdict)
1302 {
1303     BlockDriverState *bs;
1304     Error *err;
1305     const char *name = qdict_get_str(qdict, "name");
1306
1307     if (!find_vmstate_bs()) {
1308         monitor_printf(mon, "No block device supports snapshots\n");
1309         return;
1310     }
1311
1312     bs = NULL;
1313     while ((bs = bdrv_next(bs))) {
1314         if (bdrv_can_snapshot(bs)) {
1315             err = NULL;
1316             bdrv_snapshot_delete_by_id_or_name(bs, name, &err);
1317             if (err) {
1318                 monitor_printf(mon,
1319                                "Error while deleting snapshot on device '%s':"
1320                                " %s\n",
1321                                bdrv_get_device_name(bs),
1322                                error_get_pretty(err));
1323                 error_free(err);
1324             }
1325         }
1326     }
1327 }
1328
1329 void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
1330 {
1331     BlockDriverState *bs, *bs1;
1332     QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
1333     int nb_sns, i, ret, available;
1334     int total;
1335     int *available_snapshots;
1336
1337     bs = find_vmstate_bs();
1338     if (!bs) {
1339         monitor_printf(mon, "No available block device supports snapshots\n");
1340         return;
1341     }
1342
1343     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1344     if (nb_sns < 0) {
1345         monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
1346         return;
1347     }
1348
1349     if (nb_sns == 0) {
1350         monitor_printf(mon, "There is no snapshot available.\n");
1351         return;
1352     }
1353
1354     available_snapshots = g_malloc0(sizeof(int) * nb_sns);
1355     total = 0;
1356     for (i = 0; i < nb_sns; i++) {
1357         sn = &sn_tab[i];
1358         available = 1;
1359         bs1 = NULL;
1360
1361         while ((bs1 = bdrv_next(bs1))) {
1362             if (bdrv_can_snapshot(bs1) && bs1 != bs) {
1363                 ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
1364                 if (ret < 0) {
1365                     available = 0;
1366                     break;
1367                 }
1368             }
1369         }
1370
1371         if (available) {
1372             available_snapshots[total] = i;
1373             total++;
1374         }
1375     }
1376
1377     if (total > 0) {
1378         bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL);
1379         monitor_printf(mon, "\n");
1380         for (i = 0; i < total; i++) {
1381             sn = &sn_tab[available_snapshots[i]];
1382             bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn);
1383             monitor_printf(mon, "\n");
1384         }
1385     } else {
1386         monitor_printf(mon, "There is no suitable snapshot available\n");
1387     }
1388
1389     g_free(sn_tab);
1390     g_free(available_snapshots);
1391
1392 }
1393
1394 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev)
1395 {
1396     qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK,
1397                        memory_region_name(mr), dev);
1398 }
1399
1400 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev)
1401 {
1402     qemu_ram_unset_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK);
1403 }
1404
1405 void vmstate_register_ram_global(MemoryRegion *mr)
1406 {
1407     vmstate_register_ram(mr, NULL);
1408 }