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 #include <unistd.h>
  25 #include <fcntl.h>
  26 #include <time.h>
  27 #include <errno.h>
  28 #include <sys/time.h>
  29 #include <zlib.h>
  30
  31 /* Needed early for CONFIG_BSD etc. */
  32 #include "config-host.h"
  33
  34 #ifndef _WIN32
  35 #include <sys/times.h>
  36 #include <sys/wait.h>
  37 #include <termios.h>
  38 #include <sys/mman.h>
  39 #include <sys/ioctl.h>
  40 #include <sys/resource.h>
  41 #include <sys/socket.h>
  42 #include <netinet/in.h>
  43 #include <net/if.h>
  44 #include <arpa/inet.h>
  45 #include <dirent.h>
  46 #include <netdb.h>
  47 #include <sys/select.h>
  48 #ifdef CONFIG_BSD
  49 #include <sys/stat.h>
  50 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
  51 #include <libutil.h>
  52 #else
  53 #include <util.h>
  54 #endif
  55 #ifdef __linux__
  56 #include <pty.h>
  57 #include <malloc.h>
  58 #include <linux/rtc.h>
  59 #endif
  60 #endif
  61 #endif
  62
  63 #ifdef _WIN32
  64 #include <windows.h>
  65 #include <malloc.h>
  66 #include <sys/timeb.h>
  67 #include <mmsystem.h>
  68 #define getopt_long_only getopt_long
  69 #define memalign(align, size) malloc(size)
  70 #endif
  71
  72 #include "qemu-common.h"
  73 #include "hw/hw.h"
  74 #include "hw/qdev.h"
  75 #include "net.h"
  76 #include "monitor.h"
  77 #include "sysemu.h"
  78 #include "qemu-timer.h"
  79 #include "qemu-char.h"
  80 #include "audio/audio.h"
  81 #include "migration.h"
  82 #include "qemu_socket.h"
  83 #include "qemu-queue.h"
  84 #include "cpus.h"
  85
  86 #define SELF_ANNOUNCE_ROUNDS 5
  87
  88 #ifndef ETH_P_RARP
  89 #define ETH_P_RARP 0x8035
  90 #endif
  91 #define ARP_HTYPE_ETH 0x0001
  92 #define ARP_PTYPE_IP 0x0800
  93 #define ARP_OP_REQUEST_REV 0x3
  94
  95 static int announce_self_create(uint8_t *buf,
  96                                 uint8_t *mac_addr)
  97 {
  98     /* Ethernet header. */
  99     memset(buf, 0xff, 6);         /* destination MAC addr */
 100     memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
 101     *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */
 102
 103     /* RARP header. */
 104     *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
 105     *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
 106     *(buf + 18) = 6; /* hardware addr length (ethernet) */
 107     *(buf + 19) = 4; /* protocol addr length (IPv4) */
 108     *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
 109     memcpy(buf + 22, mac_addr, 6); /* source hw addr */
 110     memset(buf + 28, 0x00, 4);     /* source protocol addr */
 111     memcpy(buf + 32, mac_addr, 6); /* target hw addr */
 112     memset(buf + 38, 0x00, 4);     /* target protocol addr */
 113
 114     /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
 115     memset(buf + 42, 0x00, 18);
 116
 117     return 60; /* len (FCS will be added by hardware) */
 118 }
 119
 120 static void qemu_announce_self_iter(NICState *nic, void *opaque)
 121 {
 122     uint8_t buf[60];
 123     int len;
 124
 125     len = announce_self_create(buf, nic->conf->macaddr.a);
 126
 127     qemu_send_packet_raw(&nic->nc, buf, len);
 128 }
 129
 130
 131 static void qemu_announce_self_once(void *opaque)
 132 {
 133     static int count = SELF_ANNOUNCE_ROUNDS;
 134     QEMUTimer *timer = *(QEMUTimer **)opaque;
 135
 136     qemu_foreach_nic(qemu_announce_self_iter, NULL);
 137
 138     if (--count) {
 139         /* delay 50ms, 150ms, 250ms, ... */
 140         qemu_mod_timer(timer, qemu_get_clock_ms(rt_clock) +
 141                        50 + (SELF_ANNOUNCE_ROUNDS - count - 1) * 100);
 142     } else {
 143             qemu_del_timer(timer);
 144             qemu_free_timer(timer);
 145     }
 146 }
 147
 148 void qemu_announce_self(void)
 149 {
 150         static QEMUTimer *timer;
 151         timer = qemu_new_timer_ms(rt_clock, qemu_announce_self_once, &timer);
 152         qemu_announce_self_once(&timer);
 153 }
 154
 155 /***********************************************************/
 156 /* savevm/loadvm support */
 157
 158 #define IO_BUF_SIZE 32768
 159
 160 struct QEMUFile {
 161     QEMUFilePutBufferFunc *put_buffer;
 162     QEMUFileGetBufferFunc *get_buffer;
 163     QEMUFileCloseFunc *close;
 164     QEMUFileRateLimit *rate_limit;
 165     QEMUFileSetRateLimit *set_rate_limit;
 166     QEMUFileGetRateLimit *get_rate_limit;
 167     void *opaque;
 168     int is_write;
 169
 170     int64_t buf_offset; /* start of buffer when writing, end of buffer
 171                            when reading */
 172     int buf_index;
 173     int buf_size; /* 0 when writing */
 174     uint8_t buf[IO_BUF_SIZE];
 175
 176     int has_error;
 177 };
 178
 179 typedef struct QEMUFileStdio
 180 {
 181     FILE *stdio_file;
 182     QEMUFile *file;
 183 } QEMUFileStdio;
 184
 185 typedef struct QEMUFileSocket
 186 {
 187     int fd;
 188     QEMUFile *file;
 189 } QEMUFileSocket;
 190
 191 static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 192 {
 193     QEMUFileSocket *s = opaque;
 194     ssize_t len;
 195
 196     do {
 197         len = qemu_recv(s->fd, buf, size, 0);
 198     } while (len == -1 && socket_error() == EINTR);
 199
 200     if (len == -1)
 201         len = -socket_error();
 202
 203     return len;
 204 }
 205
 206 static int socket_close(void *opaque)
 207 {
 208     QEMUFileSocket *s = opaque;
 209     g_free(s);
 210     return 0;
 211 }
 212
 213 static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
 214 {
 215     QEMUFileStdio *s = opaque;
 216     return fwrite(buf, 1, size, s->stdio_file);
 217 }
 218
 219 static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 220 {
 221     QEMUFileStdio *s = opaque;
 222     FILE *fp = s->stdio_file;
 223     int bytes;
 224
 225     do {
 226         clearerr(fp);
 227         bytes = fread(buf, 1, size, fp);
 228     } while ((bytes == 0) && ferror(fp) && (errno == EINTR));
 229     return bytes;
 230 }
 231
 232 static int stdio_pclose(void *opaque)
 233 {
 234     QEMUFileStdio *s = opaque;
 235     int ret;
 236     ret = pclose(s->stdio_file);
 237     g_free(s);
 238     return ret;
 239 }
 240
 241 static int stdio_fclose(void *opaque)
 242 {
 243     QEMUFileStdio *s = opaque;
 244     fclose(s->stdio_file);
 245     g_free(s);
 246     return 0;
 247 }
 248
 249 QEMUFile *qemu_popen(FILE *stdio_file, const char *mode)
 250 {
 251     QEMUFileStdio *s;
 252
 253     if (stdio_file == NULL || mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) {
 254         fprintf(stderr, "qemu_popen: Argument validity check failed\n");
 255         return NULL;
 256     }
 257
 258     s = g_malloc0(sizeof(QEMUFileStdio));
 259
 260     s->stdio_file = stdio_file;
 261
 262     if(mode[0] == 'r') {
 263         s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_pclose,
 264                                  NULL, NULL, NULL);
 265     } else {
 266         s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_pclose,
 267                                  NULL, NULL, NULL);
 268     }
 269     return s->file;
 270 }
 271
 272 QEMUFile *qemu_popen_cmd(const char *command, const char *mode)
 273 {
 274     FILE *popen_file;
 275
 276     popen_file = popen(command, mode);
 277     if(popen_file == NULL) {
 278         return NULL;
 279     }
 280
 281     return qemu_popen(popen_file, mode);
 282 }
 283
 284 int qemu_stdio_fd(QEMUFile *f)
 285 {
 286     QEMUFileStdio *p;
 287     int fd;
 288
 289     p = (QEMUFileStdio *)f->opaque;
 290     fd = fileno(p->stdio_file);
 291
 292     return fd;
 293 }
 294
 295 QEMUFile *qemu_fdopen(int fd, const char *mode)
 296 {
 297     QEMUFileStdio *s;
 298
 299     if (mode == NULL ||
 300         (mode[0] != 'r' && mode[0] != 'w') ||
 301         mode[1] != 'b' || mode[2] != 0) {
 302         fprintf(stderr, "qemu_fdopen: Argument validity check failed\n");
 303         return NULL;
 304     }
 305
 306     s = g_malloc0(sizeof(QEMUFileStdio));
 307     s->stdio_file = fdopen(fd, mode);
 308     if (!s->stdio_file)
 309         goto fail;
 310
 311     if(mode[0] == 'r') {
 312         s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_fclose,
 313                                  NULL, NULL, NULL);
 314     } else {
 315         s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_fclose,
 316                                  NULL, NULL, NULL);
 317     }
 318     return s->file;
 319
 320 fail:
 321     g_free(s);
 322     return NULL;
 323 }
 324
 325 QEMUFile *qemu_fopen_socket(int fd)
 326 {
 327     QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
 328
 329     s->fd = fd;
 330     s->file = qemu_fopen_ops(s, NULL, socket_get_buffer, socket_close,
 331                              NULL, NULL, NULL);
 332     return s->file;
 333 }
 334
 335 static int file_put_buffer(void *opaque, const uint8_t *buf,
 336                             int64_t pos, int size)
 337 {
 338     QEMUFileStdio *s = opaque;
 339     fseek(s->stdio_file, pos, SEEK_SET);
 340     return fwrite(buf, 1, size, s->stdio_file);
 341 }
 342
 343 static int file_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 344 {
 345     QEMUFileStdio *s = opaque;
 346     fseek(s->stdio_file, pos, SEEK_SET);
 347     return fread(buf, 1, size, s->stdio_file);
 348 }
 349
 350 QEMUFile *qemu_fopen(const char *filename, const char *mode)
 351 {
 352     QEMUFileStdio *s;
 353
 354     if (mode == NULL ||
 355         (mode[0] != 'r' && mode[0] != 'w') ||
 356         mode[1] != 'b' || mode[2] != 0) {
 357         fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
 358         return NULL;
 359     }
 360
 361     s = g_malloc0(sizeof(QEMUFileStdio));
 362
 363     s->stdio_file = fopen(filename, mode);
 364     if (!s->stdio_file)
 365         goto fail;
 366
 367     if(mode[0] == 'w') {
 368         s->file = qemu_fopen_ops(s, file_put_buffer, NULL, stdio_fclose,
 369                                  NULL, NULL, NULL);
 370     } else {
 371         s->file = qemu_fopen_ops(s, NULL, file_get_buffer, stdio_fclose,
 372                                NULL, NULL, NULL);
 373     }
 374     return s->file;
 375 fail:
 376     g_free(s);
 377     return NULL;
 378 }
 379
 380 static int block_put_buffer(void *opaque, const uint8_t *buf,
 381                            int64_t pos, int size)
 382 {
 383     bdrv_save_vmstate(opaque, buf, pos, size);
 384     return size;
 385 }
 386
 387 static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 388 {
 389     return bdrv_load_vmstate(opaque, buf, pos, size);
 390 }
 391
 392 static int bdrv_fclose(void *opaque)
 393 {
 394     return 0;
 395 }
 396
 397 static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
 398 {
 399     if (is_writable)
 400         return qemu_fopen_ops(bs, block_put_buffer, NULL, bdrv_fclose,
 401                               NULL, NULL, NULL);
 402     return qemu_fopen_ops(bs, NULL, block_get_buffer, bdrv_fclose, NULL, NULL, NULL);
 403 }
 404
 405 QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer,
 406                          QEMUFileGetBufferFunc *get_buffer,
 407                          QEMUFileCloseFunc *close,
 408                          QEMUFileRateLimit *rate_limit,
 409                          QEMUFileSetRateLimit *set_rate_limit,
 410                          QEMUFileGetRateLimit *get_rate_limit)
 411 {
 412     QEMUFile *f;
 413
 414     f = g_malloc0(sizeof(QEMUFile));
 415
 416     f->opaque = opaque;
 417     f->put_buffer = put_buffer;
 418     f->get_buffer = get_buffer;
 419     f->close = close;
 420     f->rate_limit = rate_limit;
 421     f->set_rate_limit = set_rate_limit;
 422     f->get_rate_limit = get_rate_limit;
 423     f->is_write = 0;
 424
 425     return f;
 426 }
 427
 428 int qemu_file_has_error(QEMUFile *f)
 429 {
 430     return f->has_error;
 431 }
 432
 433 void qemu_file_set_error(QEMUFile *f)
 434 {
 435     f->has_error = 1;
 436 }
 437
 438 void qemu_fflush(QEMUFile *f)
 439 {
 440     if (!f->put_buffer)
 441         return;
 442
 443     if (f->is_write && f->buf_index > 0) {
 444         int len;
 445
 446         len = f->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index);
 447         if (len > 0)
 448             f->buf_offset += f->buf_index;
 449         else
 450             f->has_error = 1;
 451         f->buf_index = 0;
 452     }
 453 }
 454
 455 static void qemu_fill_buffer(QEMUFile *f)
 456 {
 457     int len;
 458     int pending;
 459
 460     if (!f->get_buffer)
 461         return;
 462
 463     if (f->is_write)
 464         abort();
 465
 466     pending = f->buf_size - f->buf_index;
 467     if (pending > 0) {
 468         memmove(f->buf, f->buf + f->buf_index, pending);
 469     }
 470     f->buf_index = 0;
 471     f->buf_size = pending;
 472
 473     len = f->get_buffer(f->opaque, f->buf + pending, f->buf_offset,
 474                         IO_BUF_SIZE - pending);
 475     if (len > 0) {
 476         f->buf_size += len;
 477         f->buf_offset += len;
 478     } else if (len != -EAGAIN)
 479         f->has_error = 1;
 480 }
 481
 482 int qemu_fclose(QEMUFile *f)
 483 {
 484     int ret = 0;
 485     qemu_fflush(f);
 486     if (f->close)
 487         ret = f->close(f->opaque);
 488     g_free(f);
 489     return ret;
 490 }
 491
 492 void qemu_file_put_notify(QEMUFile *f)
 493 {
 494     f->put_buffer(f->opaque, NULL, 0, 0);
 495 }
 496
 497 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
 498 {
 499     int l;
 500
 501     if (!f->has_error && f->is_write == 0 && f->buf_index > 0) {
 502         fprintf(stderr,
 503                 "Attempted to write to buffer while read buffer is not empty\n");
 504         abort();
 505     }
 506
 507     while (!f->has_error && size > 0) {
 508         l = IO_BUF_SIZE - f->buf_index;
 509         if (l > size)
 510             l = size;
 511         memcpy(f->buf + f->buf_index, buf, l);
 512         f->is_write = 1;
 513         f->buf_index += l;
 514         buf += l;
 515         size -= l;
 516         if (f->buf_index >= IO_BUF_SIZE)
 517             qemu_fflush(f);
 518     }
 519 }
 520
 521 void qemu_put_byte(QEMUFile *f, int v)
 522 {
 523     if (!f->has_error && f->is_write == 0 && f->buf_index > 0) {
 524         fprintf(stderr,
 525                 "Attempted to write to buffer while read buffer is not empty\n");
 526         abort();
 527     }
 528
 529     f->buf[f->buf_index++] = v;
 530     f->is_write = 1;
 531     if (f->buf_index >= IO_BUF_SIZE)
 532         qemu_fflush(f);
 533 }
 534
 535 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size1)
 536 {
 537     int size, l;
 538
 539     if (f->is_write) {
 540         abort();
 541     }
 542
 543     size = size1;
 544     while (size > 0) {
 545         l = f->buf_size - f->buf_index;
 546         if (l == 0) {
 547             qemu_fill_buffer(f);
 548             l = f->buf_size - f->buf_index;
 549             if (l == 0) {
 550                 break;
 551             }
 552         }
 553         if (l > size) {
 554             l = size;
 555         }
 556         memcpy(buf, f->buf + f->buf_index, l);
 557         f->buf_index += l;
 558         buf += l;
 559         size -= l;
 560     }
 561     return size1 - size;
 562 }
 563
 564 static int qemu_peek_byte(QEMUFile *f)
 565 {
 566     if (f->is_write) {
 567         abort();
 568     }
 569
 570     if (f->buf_index >= f->buf_size) {
 571         qemu_fill_buffer(f);
 572         if (f->buf_index >= f->buf_size) {
 573             return 0;
 574         }
 575     }
 576     return f->buf[f->buf_index];
 577 }
 578
 579 int qemu_get_byte(QEMUFile *f)
 580 {
 581     int result;
 582
 583     result = qemu_peek_byte(f);
 584
 585     if (f->buf_index < f->buf_size) {
 586         f->buf_index++;
 587     }
 588     return result;
 589 }
 590
 591 int64_t qemu_ftell(QEMUFile *f)
 592 {
 593     return f->buf_offset - f->buf_size + f->buf_index;
 594 }
 595
 596 int64_t qemu_fseek(QEMUFile *f, int64_t pos, int whence)
 597 {
 598     if (whence == SEEK_SET) {
 599         /* nothing to do */
 600     } else if (whence == SEEK_CUR) {
 601         pos += qemu_ftell(f);
 602     } else {
 603         /* SEEK_END not supported */
 604         return -1;
 605     }
 606     if (f->put_buffer) {
 607         qemu_fflush(f);
 608         f->buf_offset = pos;
 609     } else {
 610         f->buf_offset = pos;
 611         f->buf_index = 0;
 612         f->buf_size = 0;
 613     }
 614     return pos;
 615 }
 616
 617 int qemu_file_rate_limit(QEMUFile *f)
 618 {
 619     if (f->rate_limit)
 620         return f->rate_limit(f->opaque);
 621
 622     return 0;
 623 }
 624
 625 int64_t qemu_file_get_rate_limit(QEMUFile *f)
 626 {
 627     if (f->get_rate_limit)
 628         return f->get_rate_limit(f->opaque);
 629
 630     return 0;
 631 }
 632
 633 int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate)
 634 {
 635     /* any failed or completed migration keeps its state to allow probing of
 636      * migration data, but has no associated file anymore */
 637     if (f && f->set_rate_limit)
 638         return f->set_rate_limit(f->opaque, new_rate);
 639
 640     return 0;
 641 }
 642
 643 void qemu_put_be16(QEMUFile *f, unsigned int v)
 644 {
 645     qemu_put_byte(f, v >> 8);
 646     qemu_put_byte(f, v);
 647 }
 648
 649 void qemu_put_be32(QEMUFile *f, unsigned int v)
 650 {
 651     qemu_put_byte(f, v >> 24);
 652     qemu_put_byte(f, v >> 16);
 653     qemu_put_byte(f, v >> 8);
 654     qemu_put_byte(f, v);
 655 }
 656
 657 void qemu_put_be64(QEMUFile *f, uint64_t v)
 658 {
 659     qemu_put_be32(f, v >> 32);
 660     qemu_put_be32(f, v);
 661 }
 662
 663 unsigned int qemu_get_be16(QEMUFile *f)
 664 {
 665     unsigned int v;
 666     v = qemu_get_byte(f) << 8;
 667     v |= qemu_get_byte(f);
 668     return v;
 669 }
 670
 671 unsigned int qemu_get_be32(QEMUFile *f)
 672 {
 673     unsigned int v;
 674     v = qemu_get_byte(f) << 24;
 675     v |= qemu_get_byte(f) << 16;
 676     v |= qemu_get_byte(f) << 8;
 677     v |= qemu_get_byte(f);
 678     return v;
 679 }
 680
 681 uint64_t qemu_get_be64(QEMUFile *f)
 682 {
 683     uint64_t v;
 684     v = (uint64_t)qemu_get_be32(f) << 32;
 685     v |= qemu_get_be32(f);
 686     return v;
 687 }
 688
 689 /* bool */
 690
 691 static int get_bool(QEMUFile *f, void *pv, size_t size)
 692 {
 693     bool *v = pv;
 694     *v = qemu_get_byte(f);
 695     return 0;
 696 }
 697
 698 static void put_bool(QEMUFile *f, void *pv, size_t size)
 699 {
 700     bool *v = pv;
 701     qemu_put_byte(f, *v);
 702 }
 703
 704 const VMStateInfo vmstate_info_bool = {
 705     .name = "bool",
 706     .get  = get_bool,
 707     .put  = put_bool,
 708 };
 709
 710 /* 8 bit int */
 711
 712 static int get_int8(QEMUFile *f, void *pv, size_t size)
 713 {
 714     int8_t *v = pv;
 715     qemu_get_s8s(f, v);
 716     return 0;
 717 }
 718
 719 static void put_int8(QEMUFile *f, void *pv, size_t size)
 720 {
 721     int8_t *v = pv;
 722     qemu_put_s8s(f, v);
 723 }
 724
 725 const VMStateInfo vmstate_info_int8 = {
 726     .name = "int8",
 727     .get  = get_int8,
 728     .put  = put_int8,
 729 };
 730
 731 /* 16 bit int */
 732
 733 static int get_int16(QEMUFile *f, void *pv, size_t size)
 734 {
 735     int16_t *v = pv;
 736     qemu_get_sbe16s(f, v);
 737     return 0;
 738 }
 739
 740 static void put_int16(QEMUFile *f, void *pv, size_t size)
 741 {
 742     int16_t *v = pv;
 743     qemu_put_sbe16s(f, v);
 744 }
 745
 746 const VMStateInfo vmstate_info_int16 = {
 747     .name = "int16",
 748     .get  = get_int16,
 749     .put  = put_int16,
 750 };
 751
 752 /* 32 bit int */
 753
 754 static int get_int32(QEMUFile *f, void *pv, size_t size)
 755 {
 756     int32_t *v = pv;
 757     qemu_get_sbe32s(f, v);
 758     return 0;
 759 }
 760
 761 static void put_int32(QEMUFile *f, void *pv, size_t size)
 762 {
 763     int32_t *v = pv;
 764     qemu_put_sbe32s(f, v);
 765 }
 766
 767 const VMStateInfo vmstate_info_int32 = {
 768     .name = "int32",
 769     .get  = get_int32,
 770     .put  = put_int32,
 771 };
 772
 773 /* 32 bit int. See that the received value is the same than the one
 774    in the field */
 775
 776 static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
 777 {
 778     int32_t *v = pv;
 779     int32_t v2;
 780     qemu_get_sbe32s(f, &v2);
 781
 782     if (*v == v2)
 783         return 0;
 784     return -EINVAL;
 785 }
 786
 787 const VMStateInfo vmstate_info_int32_equal = {
 788     .name = "int32 equal",
 789     .get  = get_int32_equal,
 790     .put  = put_int32,
 791 };
 792
 793 /* 32 bit int. See that the received value is the less or the same
 794    than the one in the field */
 795
 796 static int get_int32_le(QEMUFile *f, void *pv, size_t size)
 797 {
 798     int32_t *old = pv;
 799     int32_t new;
 800     qemu_get_sbe32s(f, &new);
 801
 802     if (*old <= new)
 803         return 0;
 804     return -EINVAL;
 805 }
 806
 807 const VMStateInfo vmstate_info_int32_le = {
 808     .name = "int32 equal",
 809     .get  = get_int32_le,
 810     .put  = put_int32,
 811 };
 812
 813 /* 64 bit int */
 814
 815 static int get_int64(QEMUFile *f, void *pv, size_t size)
 816 {
 817     int64_t *v = pv;
 818     qemu_get_sbe64s(f, v);
 819     return 0;
 820 }
 821
 822 static void put_int64(QEMUFile *f, void *pv, size_t size)
 823 {
 824     int64_t *v = pv;
 825     qemu_put_sbe64s(f, v);
 826 }
 827
 828 const VMStateInfo vmstate_info_int64 = {
 829     .name = "int64",
 830     .get  = get_int64,
 831     .put  = put_int64,
 832 };
 833
 834 /* 8 bit unsigned int */
 835
 836 static int get_uint8(QEMUFile *f, void *pv, size_t size)
 837 {
 838     uint8_t *v = pv;
 839     qemu_get_8s(f, v);
 840     return 0;
 841 }
 842
 843 static void put_uint8(QEMUFile *f, void *pv, size_t size)
 844 {
 845     uint8_t *v = pv;
 846     qemu_put_8s(f, v);
 847 }
 848
 849 const VMStateInfo vmstate_info_uint8 = {
 850     .name = "uint8",
 851     .get  = get_uint8,
 852     .put  = put_uint8,
 853 };
 854
 855 /* 16 bit unsigned int */
 856
 857 static int get_uint16(QEMUFile *f, void *pv, size_t size)
 858 {
 859     uint16_t *v = pv;
 860     qemu_get_be16s(f, v);
 861     return 0;
 862 }
 863
 864 static void put_uint16(QEMUFile *f, void *pv, size_t size)
 865 {
 866     uint16_t *v = pv;
 867     qemu_put_be16s(f, v);
 868 }
 869
 870 const VMStateInfo vmstate_info_uint16 = {
 871     .name = "uint16",
 872     .get  = get_uint16,
 873     .put  = put_uint16,
 874 };
 875
 876 /* 32 bit unsigned int */
 877
 878 static int get_uint32(QEMUFile *f, void *pv, size_t size)
 879 {
 880     uint32_t *v = pv;
 881     qemu_get_be32s(f, v);
 882     return 0;
 883 }
 884
 885 static void put_uint32(QEMUFile *f, void *pv, size_t size)
 886 {
 887     uint32_t *v = pv;
 888     qemu_put_be32s(f, v);
 889 }
 890
 891 const VMStateInfo vmstate_info_uint32 = {
 892     .name = "uint32",
 893     .get  = get_uint32,
 894     .put  = put_uint32,
 895 };
 896
 897 /* 32 bit uint. See that the received value is the same than the one
 898    in the field */
 899
 900 static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
 901 {
 902     uint32_t *v = pv;
 903     uint32_t v2;
 904     qemu_get_be32s(f, &v2);
 905
 906     if (*v == v2) {
 907         return 0;
 908     }
 909     return -EINVAL;
 910 }
 911
 912 const VMStateInfo vmstate_info_uint32_equal = {
 913     .name = "uint32 equal",
 914     .get  = get_uint32_equal,
 915     .put  = put_uint32,
 916 };
 917
 918 /* 64 bit unsigned int */
 919
 920 static int get_uint64(QEMUFile *f, void *pv, size_t size)
 921 {
 922     uint64_t *v = pv;
 923     qemu_get_be64s(f, v);
 924     return 0;
 925 }
 926
 927 static void put_uint64(QEMUFile *f, void *pv, size_t size)
 928 {
 929     uint64_t *v = pv;
 930     qemu_put_be64s(f, v);
 931 }
 932
 933 const VMStateInfo vmstate_info_uint64 = {
 934     .name = "uint64",
 935     .get  = get_uint64,
 936     .put  = put_uint64,
 937 };
 938
 939 /* 8 bit int. See that the received value is the same than the one
 940    in the field */
 941
 942 static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
 943 {
 944     uint8_t *v = pv;
 945     uint8_t v2;
 946     qemu_get_8s(f, &v2);
 947
 948     if (*v == v2)
 949         return 0;
 950     return -EINVAL;
 951 }
 952
 953 const VMStateInfo vmstate_info_uint8_equal = {
 954     .name = "uint8 equal",
 955     .get  = get_uint8_equal,
 956     .put  = put_uint8,
 957 };
 958
 959 /* 16 bit unsigned int int. See that the received value is the same than the one
 960    in the field */
 961
 962 static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
 963 {
 964     uint16_t *v = pv;
 965     uint16_t v2;
 966     qemu_get_be16s(f, &v2);
 967
 968     if (*v == v2)
 969         return 0;
 970     return -EINVAL;
 971 }
 972
 973 const VMStateInfo vmstate_info_uint16_equal = {
 974     .name = "uint16 equal",
 975     .get  = get_uint16_equal,
 976     .put  = put_uint16,
 977 };
 978
 979 /* timers  */
 980
 981 static int get_timer(QEMUFile *f, void *pv, size_t size)
 982 {
 983     QEMUTimer *v = pv;
 984     qemu_get_timer(f, v);
 985     return 0;
 986 }
 987
 988 static void put_timer(QEMUFile *f, void *pv, size_t size)
 989 {
 990     QEMUTimer *v = pv;
 991     qemu_put_timer(f, v);
 992 }
 993
 994 const VMStateInfo vmstate_info_timer = {
 995     .name = "timer",
 996     .get  = get_timer,
 997     .put  = put_timer,
 998 };
 999
1000 /* uint8_t buffers */
1001
1002 static int get_buffer(QEMUFile *f, void *pv, size_t size)
1003 {
1004     uint8_t *v = pv;
1005     qemu_get_buffer(f, v, size);
1006     return 0;
1007 }
1008
1009 static void put_buffer(QEMUFile *f, void *pv, size_t size)
1010 {
1011     uint8_t *v = pv;
1012     qemu_put_buffer(f, v, size);
1013 }
1014
1015 const VMStateInfo vmstate_info_buffer = {
1016     .name = "buffer",
1017     .get  = get_buffer,
1018     .put  = put_buffer,
1019 };
1020
1021 /* unused buffers: space that was used for some fields that are
1022    not useful anymore */
1023
1024 static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
1025 {
1026     uint8_t buf[1024];
1027     int block_len;
1028
1029     while (size > 0) {
1030         block_len = MIN(sizeof(buf), size);
1031         size -= block_len;
1032         qemu_get_buffer(f, buf, block_len);
1033     }
1034    return 0;
1035 }
1036
1037 static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
1038 {
1039     static const uint8_t buf[1024];
1040     int block_len;
1041
1042     while (size > 0) {
1043         block_len = MIN(sizeof(buf), size);
1044         size -= block_len;
1045         qemu_put_buffer(f, buf, block_len);
1046     }
1047 }
1048
1049 const VMStateInfo vmstate_info_unused_buffer = {
1050     .name = "unused_buffer",
1051     .get  = get_unused_buffer,
1052     .put  = put_unused_buffer,
1053 };
1054
1055 typedef struct CompatEntry {
1056     char idstr[256];
1057     int instance_id;
1058 } CompatEntry;
1059
1060 typedef struct SaveStateEntry {
1061     QTAILQ_ENTRY(SaveStateEntry) entry;
1062     char idstr[256];
1063     int instance_id;
1064     int alias_id;
1065     int version_id;
1066     int section_id;
1067     SaveSetParamsHandler *set_params;
1068     SaveLiveStateHandler *save_live_state;
1069     SaveStateHandler *save_state;
1070     LoadStateHandler *load_state;
1071     const VMStateDescription *vmsd;
1072     void *opaque;
1073     CompatEntry *compat;
1074     int no_migrate;
1075 } SaveStateEntry;
1076
1077
1078 static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
1079     QTAILQ_HEAD_INITIALIZER(savevm_handlers);
1080 static int global_section_id;
1081
1082 static int calculate_new_instance_id(const char *idstr)
1083 {
1084     SaveStateEntry *se;
1085     int instance_id = 0;
1086
1087     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1088         if (strcmp(idstr, se->idstr) == 0
1089             && instance_id <= se->instance_id) {
1090             instance_id = se->instance_id + 1;
1091         }
1092     }
1093     return instance_id;
1094 }
1095
1096 static int calculate_compat_instance_id(const char *idstr)
1097 {
1098     SaveStateEntry *se;
1099     int instance_id = 0;
1100
1101     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1102         if (!se->compat)
1103             continue;
1104
1105         if (strcmp(idstr, se->compat->idstr) == 0
1106             && instance_id <= se->compat->instance_id) {
1107             instance_id = se->compat->instance_id + 1;
1108         }
1109     }
1110     return instance_id;
1111 }
1112
1113 /* TODO: Individual devices generally have very little idea about the rest
1114    of the system, so instance_id should be removed/replaced.
1115    Meanwhile pass -1 as instance_id if you do not already have a clearly
1116    distinguishing id for all instances of your device class. */
1117 int register_savevm_live(DeviceState *dev,
1118                          const char *idstr,
1119                          int instance_id,
1120                          int version_id,
1121                          SaveSetParamsHandler *set_params,
1122                          SaveLiveStateHandler *save_live_state,
1123                          SaveStateHandler *save_state,
1124                          LoadStateHandler *load_state,
1125                          void *opaque)
1126 {
1127     SaveStateEntry *se;
1128
1129     se = g_malloc0(sizeof(SaveStateEntry));
1130     se->version_id = version_id;
1131     se->section_id = global_section_id++;
1132     se->set_params = set_params;
1133     se->save_live_state = save_live_state;
1134     se->save_state = save_state;
1135     se->load_state = load_state;
1136     se->opaque = opaque;
1137     se->vmsd = NULL;
1138     se->no_migrate = 0;
1139
1140     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1141         char *id = dev->parent_bus->info->get_dev_path(dev);
1142         if (id) {
1143             pstrcpy(se->idstr, sizeof(se->idstr), id);
1144             pstrcat(se->idstr, sizeof(se->idstr), "/");
1145             g_free(id);
1146
1147             se->compat = g_malloc0(sizeof(CompatEntry));
1148             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
1149             se->compat->instance_id = instance_id == -1 ?
1150                          calculate_compat_instance_id(idstr) : instance_id;
1151             instance_id = -1;
1152         }
1153     }
1154     pstrcat(se->idstr, sizeof(se->idstr), idstr);
1155
1156     if (instance_id == -1) {
1157         se->instance_id = calculate_new_instance_id(se->idstr);
1158     } else {
1159         se->instance_id = instance_id;
1160     }
1161     assert(!se->compat || se->instance_id == 0);
1162     /* add at the end of list */
1163     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1164     return 0;
1165 }
1166
1167 int register_savevm(DeviceState *dev,
1168                     const char *idstr,
1169                     int instance_id,
1170                     int version_id,
1171                     SaveStateHandler *save_state,
1172                     LoadStateHandler *load_state,
1173                     void *opaque)
1174 {
1175     return register_savevm_live(dev, idstr, instance_id, version_id,
1176                                 NULL, NULL, save_state, load_state, opaque);
1177 }
1178
1179 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
1180 {
1181     SaveStateEntry *se, *new_se;
1182     char id[256] = "";
1183
1184     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1185         char *path = dev->parent_bus->info->get_dev_path(dev);
1186         if (path) {
1187             pstrcpy(id, sizeof(id), path);
1188             pstrcat(id, sizeof(id), "/");
1189             g_free(path);
1190         }
1191     }
1192     pstrcat(id, sizeof(id), idstr);
1193
1194     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1195         if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1196             QTAILQ_REMOVE(&savevm_handlers, se, entry);
1197             if (se->compat) {
1198                 g_free(se->compat);
1199             }
1200             g_free(se);
1201         }
1202     }
1203 }
1204
1205 /* mark a device as not to be migrated, that is the device should be
1206    unplugged before migration */
1207 void register_device_unmigratable(DeviceState *dev, const char *idstr,
1208                                                             void *opaque)
1209 {
1210     SaveStateEntry *se;
1211     char id[256] = "";
1212
1213     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1214         char *path = dev->parent_bus->info->get_dev_path(dev);
1215         if (path) {
1216             pstrcpy(id, sizeof(id), path);
1217             pstrcat(id, sizeof(id), "/");
1218             g_free(path);
1219         }
1220     }
1221     pstrcat(id, sizeof(id), idstr);
1222
1223     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1224         if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1225             se->no_migrate = 1;
1226         }
1227     }
1228 }
1229
1230 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
1231                                    const VMStateDescription *vmsd,
1232                                    void *opaque, int alias_id,
1233                                    int required_for_version)
1234 {
1235     SaveStateEntry *se;
1236
1237     /* If this triggers, alias support can be dropped for the vmsd. */
1238     assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);
1239
1240     se = g_malloc0(sizeof(SaveStateEntry));
1241     se->version_id = vmsd->version_id;
1242     se->section_id = global_section_id++;
1243     se->save_live_state = NULL;
1244     se->save_state = NULL;
1245     se->load_state = NULL;
1246     se->opaque = opaque;
1247     se->vmsd = vmsd;
1248     se->alias_id = alias_id;
1249     se->no_migrate = vmsd->unmigratable;
1250
1251     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1252         char *id = dev->parent_bus->info->get_dev_path(dev);
1253         if (id) {
1254             pstrcpy(se->idstr, sizeof(se->idstr), id);
1255             pstrcat(se->idstr, sizeof(se->idstr), "/");
1256             g_free(id);
1257
1258             se->compat = g_malloc0(sizeof(CompatEntry));
1259             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
1260             se->compat->instance_id = instance_id == -1 ?
1261                          calculate_compat_instance_id(vmsd->name) : instance_id;
1262             instance_id = -1;
1263         }
1264     }
1265     pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
1266
1267     if (instance_id == -1) {
1268         se->instance_id = calculate_new_instance_id(se->idstr);
1269     } else {
1270         se->instance_id = instance_id;
1271     }
1272     assert(!se->compat || se->instance_id == 0);
1273     /* add at the end of list */
1274     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1275     return 0;
1276 }
1277
1278 int vmstate_register(DeviceState *dev, int instance_id,
1279                      const VMStateDescription *vmsd, void *opaque)
1280 {
1281     return vmstate_register_with_alias_id(dev, instance_id, vmsd,
1282                                           opaque, -1, 0);
1283 }
1284
1285 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
1286                         void *opaque)
1287 {
1288     SaveStateEntry *se, *new_se;
1289
1290     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1291         if (se->vmsd == vmsd && se->opaque == opaque) {
1292             QTAILQ_REMOVE(&savevm_handlers, se, entry);
1293             if (se->compat) {
1294                 g_free(se->compat);
1295             }
1296             g_free(se);
1297         }
1298     }
1299 }
1300
1301 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1302                                     void *opaque);
1303 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1304                                    void *opaque);
1305
1306 int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
1307                        void *opaque, int version_id)
1308 {
1309     VMStateField *field = vmsd->fields;
1310     int ret;
1311
1312     if (version_id > vmsd->version_id) {
1313         return -EINVAL;
1314     }
1315     if (version_id < vmsd->minimum_version_id_old) {
1316         return -EINVAL;
1317     }
1318     if  (version_id < vmsd->minimum_version_id) {
1319         return vmsd->load_state_old(f, opaque, version_id);
1320     }
1321     if (vmsd->pre_load) {
1322         int ret = vmsd->pre_load(opaque);
1323         if (ret)
1324             return ret;
1325     }
1326     while(field->name) {
1327         if ((field->field_exists &&
1328              field->field_exists(opaque, version_id)) ||
1329             (!field->field_exists &&
1330              field->version_id <= version_id)) {
1331             void *base_addr = opaque + field->offset;
1332             int i, n_elems = 1;
1333             int size = field->size;
1334
1335             if (field->flags & VMS_VBUFFER) {
1336                 size = *(int32_t *)(opaque+field->size_offset);
1337                 if (field->flags & VMS_MULTIPLY) {
1338                     size *= field->size;
1339                 }
1340             }
1341             if (field->flags & VMS_ARRAY) {
1342                 n_elems = field->num;
1343             } else if (field->flags & VMS_VARRAY_INT32) {
1344                 n_elems = *(int32_t *)(opaque+field->num_offset);
1345             } else if (field->flags & VMS_VARRAY_UINT32) {
1346                 n_elems = *(uint32_t *)(opaque+field->num_offset);
1347             } else if (field->flags & VMS_VARRAY_UINT16) {
1348                 n_elems = *(uint16_t *)(opaque+field->num_offset);
1349             } else if (field->flags & VMS_VARRAY_UINT8) {
1350                 n_elems = *(uint8_t *)(opaque+field->num_offset);
1351             }
1352             if (field->flags & VMS_POINTER) {
1353                 base_addr = *(void **)base_addr + field->start;
1354             }
1355             for (i = 0; i < n_elems; i++) {
1356                 void *addr = base_addr + size * i;
1357
1358                 if (field->flags & VMS_ARRAY_OF_POINTER) {
1359                     addr = *(void **)addr;
1360                 }
1361                 if (field->flags & VMS_STRUCT) {
1362                     ret = vmstate_load_state(f, field->vmsd, addr, field->vmsd->version_id);
1363                 } else {
1364                     ret = field->info->get(f, addr, size);
1365
1366                 }
1367                 if (ret < 0) {
1368                     return ret;
1369                 }
1370             }
1371         }
1372         field++;
1373     }
1374     ret = vmstate_subsection_load(f, vmsd, opaque);
1375     if (ret != 0) {
1376         return ret;
1377     }
1378     if (vmsd->post_load) {
1379         return vmsd->post_load(opaque, version_id);
1380     }
1381     return 0;
1382 }
1383
1384 void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
1385                         void *opaque)
1386 {
1387     VMStateField *field = vmsd->fields;
1388
1389     if (vmsd->pre_save) {
1390         vmsd->pre_save(opaque);
1391     }
1392     while(field->name) {
1393         if (!field->field_exists ||
1394             field->field_exists(opaque, vmsd->version_id)) {
1395             void *base_addr = opaque + field->offset;
1396             int i, n_elems = 1;
1397             int size = field->size;
1398
1399             if (field->flags & VMS_VBUFFER) {
1400                 size = *(int32_t *)(opaque+field->size_offset);
1401                 if (field->flags & VMS_MULTIPLY) {
1402                     size *= field->size;
1403                 }
1404             }
1405             if (field->flags & VMS_ARRAY) {
1406                 n_elems = field->num;
1407             } else if (field->flags & VMS_VARRAY_INT32) {
1408                 n_elems = *(int32_t *)(opaque+field->num_offset);
1409             } else if (field->flags & VMS_VARRAY_UINT16) {
1410                 n_elems = *(uint16_t *)(opaque+field->num_offset);
1411             } else if (field->flags & VMS_VARRAY_UINT8) {
1412                 n_elems = *(uint8_t *)(opaque+field->num_offset);
1413             }
1414             if (field->flags & VMS_POINTER) {
1415                 base_addr = *(void **)base_addr + field->start;
1416             }
1417             for (i = 0; i < n_elems; i++) {
1418                 void *addr = base_addr + size * i;
1419
1420                 if (field->flags & VMS_ARRAY_OF_POINTER) {
1421                     addr = *(void **)addr;
1422                 }
1423                 if (field->flags & VMS_STRUCT) {
1424                     vmstate_save_state(f, field->vmsd, addr);
1425                 } else {
1426                     field->info->put(f, addr, size);
1427                 }
1428             }
1429         }
1430         field++;
1431     }
1432     vmstate_subsection_save(f, vmsd, opaque);
1433 }
1434
1435 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
1436 {
1437     if (!se->vmsd) {         /* Old style */
1438         return se->load_state(f, se->opaque, version_id);
1439     }
1440     return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
1441 }
1442
1443 static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
1444 {
1445     if (!se->vmsd) {         /* Old style */
1446         se->save_state(f, se->opaque);
1447         return;
1448     }
1449     vmstate_save_state(f,se->vmsd, se->opaque);
1450 }
1451
1452 #define QEMU_VM_FILE_MAGIC           0x5145564d
1453 #define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
1454 #define QEMU_VM_FILE_VERSION         0x00000003
1455
1456 #define QEMU_VM_EOF                  0x00
1457 #define QEMU_VM_SECTION_START        0x01
1458 #define QEMU_VM_SECTION_PART         0x02
1459 #define QEMU_VM_SECTION_END          0x03
1460 #define QEMU_VM_SECTION_FULL         0x04
1461 #define QEMU_VM_SUBSECTION           0x05
1462
1463 bool qemu_savevm_state_blocked(Monitor *mon)
1464 {
1465     SaveStateEntry *se;
1466
1467     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1468         if (se->no_migrate) {
1469             monitor_printf(mon, "state blocked by non-migratable device '%s'\n",
1470                            se->idstr);
1471             return true;
1472         }
1473     }
1474     return false;
1475 }
1476
1477 int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable,
1478                             int shared)
1479 {
1480     SaveStateEntry *se;
1481
1482     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1483         if(se->set_params == NULL) {
1484             continue;
1485         }
1486         se->set_params(blk_enable, shared, se->opaque);
1487     }
1488
1489     qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1490     qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1491
1492     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1493         int len;
1494
1495         if (se->save_live_state == NULL)
1496             continue;
1497
1498         /* Section type */
1499         qemu_put_byte(f, QEMU_VM_SECTION_START);
1500         qemu_put_be32(f, se->section_id);
1501
1502         /* ID string */
1503         len = strlen(se->idstr);
1504         qemu_put_byte(f, len);
1505         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1506
1507         qemu_put_be32(f, se->instance_id);
1508         qemu_put_be32(f, se->version_id);
1509
1510         se->save_live_state(mon, f, QEMU_VM_SECTION_START, se->opaque);
1511     }
1512
1513     if (qemu_file_has_error(f)) {
1514         qemu_savevm_state_cancel(mon, f);
1515         return -EIO;
1516     }
1517
1518     return 0;
1519 }
1520
1521 int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f)
1522 {
1523     SaveStateEntry *se;
1524     int ret = 1;
1525
1526     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1527         if (se->save_live_state == NULL)
1528             continue;
1529
1530         /* Section type */
1531         qemu_put_byte(f, QEMU_VM_SECTION_PART);
1532         qemu_put_be32(f, se->section_id);
1533
1534         ret = se->save_live_state(mon, f, QEMU_VM_SECTION_PART, se->opaque);
1535         if (!ret) {
1536             /* Do not proceed to the next vmstate before this one reported
1537                completion of the current stage. This serializes the migration
1538                and reduces the probability that a faster changing state is
1539                synchronized over and over again. */
1540             break;
1541         }
1542     }
1543
1544     if (ret)
1545         return 1;
1546
1547     if (qemu_file_has_error(f)) {
1548         qemu_savevm_state_cancel(mon, f);
1549         return -EIO;
1550     }
1551
1552     return 0;
1553 }
1554
1555 int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f)
1556 {
1557     SaveStateEntry *se;
1558
1559     cpu_synchronize_all_states();
1560
1561     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1562         if (se->save_live_state == NULL)
1563             continue;
1564
1565         /* Section type */
1566         qemu_put_byte(f, QEMU_VM_SECTION_END);
1567         qemu_put_be32(f, se->section_id);
1568
1569         se->save_live_state(mon, f, QEMU_VM_SECTION_END, se->opaque);
1570     }
1571
1572     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1573         int len;
1574
1575         if (se->save_state == NULL && se->vmsd == NULL)
1576             continue;
1577
1578         /* Section type */
1579         qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1580         qemu_put_be32(f, se->section_id);
1581
1582         /* ID string */
1583         len = strlen(se->idstr);
1584         qemu_put_byte(f, len);
1585         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1586
1587         qemu_put_be32(f, se->instance_id);
1588         qemu_put_be32(f, se->version_id);
1589
1590         vmstate_save(f, se);
1591     }
1592
1593     qemu_put_byte(f, QEMU_VM_EOF);
1594
1595     if (qemu_file_has_error(f))
1596         return -EIO;
1597
1598     return 0;
1599 }
1600
1601 void qemu_savevm_state_cancel(Monitor *mon, QEMUFile *f)
1602 {
1603     SaveStateEntry *se;
1604
1605     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1606         if (se->save_live_state) {
1607             se->save_live_state(mon, f, -1, se->opaque);
1608         }
1609     }
1610 }
1611
1612 static int qemu_savevm_state(Monitor *mon, QEMUFile *f)
1613 {
1614     int saved_vm_running;
1615     int ret;
1616
1617     saved_vm_running = runstate_is_running();
1618     vm_stop(RUN_STATE_SAVE_VM);
1619
1620     if (qemu_savevm_state_blocked(mon)) {
1621         ret = -EINVAL;
1622         goto out;
1623     }
1624
1625     ret = qemu_savevm_state_begin(mon, f, 0, 0);
1626     if (ret < 0)
1627         goto out;
1628
1629     do {
1630         ret = qemu_savevm_state_iterate(mon, f);
1631         if (ret < 0)
1632             goto out;
1633     } while (ret == 0);
1634
1635     ret = qemu_savevm_state_complete(mon, f);
1636
1637 out:
1638     if (qemu_file_has_error(f))
1639         ret = -EIO;
1640
1641     if (!ret && saved_vm_running)
1642         vm_start();
1643
1644     return ret;
1645 }
1646
1647 static SaveStateEntry *find_se(const char *idstr, int instance_id)
1648 {
1649     SaveStateEntry *se;
1650
1651     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1652         if (!strcmp(se->idstr, idstr) &&
1653             (instance_id == se->instance_id ||
1654              instance_id == se->alias_id))
1655             return se;
1656         /* Migrating from an older version? */
1657         if (strstr(se->idstr, idstr) && se->compat) {
1658             if (!strcmp(se->compat->idstr, idstr) &&
1659                 (instance_id == se->compat->instance_id ||
1660                  instance_id == se->alias_id))
1661                 return se;
1662         }
1663     }
1664     return NULL;
1665 }
1666
1667 static const VMStateDescription *vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
1668 {
1669     while(sub && sub->needed) {
1670         if (strcmp(idstr, sub->vmsd->name) == 0) {
1671             return sub->vmsd;
1672         }
1673         sub++;
1674     }
1675     return NULL;
1676 }
1677
1678 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1679                                    void *opaque)
1680 {
1681     const VMStateSubsection *sub = vmsd->subsections;
1682
1683     if (!sub || !sub->needed) {
1684         return 0;
1685     }
1686
1687     while (qemu_peek_byte(f) == QEMU_VM_SUBSECTION) {
1688         char idstr[256];
1689         int ret;
1690         uint8_t version_id, len;
1691         const VMStateDescription *sub_vmsd;
1692
1693         qemu_get_byte(f); /* subsection */
1694         len = qemu_get_byte(f);
1695         qemu_get_buffer(f, (uint8_t *)idstr, len);
1696         idstr[len] = 0;
1697         version_id = qemu_get_be32(f);
1698
1699         sub_vmsd = vmstate_get_subsection(sub, idstr);
1700         if (sub_vmsd == NULL) {
1701             return -ENOENT;
1702         }
1703         assert(!sub_vmsd->subsections);
1704         ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
1705         if (ret) {
1706             return ret;
1707         }
1708     }
1709     return 0;
1710 }
1711
1712 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1713                                     void *opaque)
1714 {
1715     const VMStateSubsection *sub = vmsd->subsections;
1716
1717     while (sub && sub->needed) {
1718         if (sub->needed(opaque)) {
1719             const VMStateDescription *vmsd = sub->vmsd;
1720             uint8_t len;
1721
1722             qemu_put_byte(f, QEMU_VM_SUBSECTION);
1723             len = strlen(vmsd->name);
1724             qemu_put_byte(f, len);
1725             qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
1726             qemu_put_be32(f, vmsd->version_id);
1727             assert(!vmsd->subsections);
1728             vmstate_save_state(f, vmsd, opaque);
1729         }
1730         sub++;
1731     }
1732 }
1733
1734 typedef struct LoadStateEntry {
1735     QLIST_ENTRY(LoadStateEntry) entry;
1736     SaveStateEntry *se;
1737     int section_id;
1738     int version_id;
1739 } LoadStateEntry;
1740
1741 int qemu_loadvm_state(QEMUFile *f)
1742 {
1743     QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
1744         QLIST_HEAD_INITIALIZER(loadvm_handlers);
1745     LoadStateEntry *le, *new_le;
1746     uint8_t section_type;
1747     unsigned int v;
1748     int ret;
1749
1750     if (qemu_savevm_state_blocked(default_mon)) {
1751         return -EINVAL;
1752     }
1753
1754     v = qemu_get_be32(f);
1755     if (v != QEMU_VM_FILE_MAGIC)
1756         return -EINVAL;
1757
1758     v = qemu_get_be32(f);
1759     if (v == QEMU_VM_FILE_VERSION_COMPAT) {
1760         fprintf(stderr, "SaveVM v2 format is obsolete and don't work anymore\n");
1761         return -ENOTSUP;
1762     }
1763     if (v != QEMU_VM_FILE_VERSION)
1764         return -ENOTSUP;
1765
1766     while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
1767         uint32_t instance_id, version_id, section_id;
1768         SaveStateEntry *se;
1769         char idstr[257];
1770         int len;
1771
1772         switch (section_type) {
1773         case QEMU_VM_SECTION_START:
1774         case QEMU_VM_SECTION_FULL:
1775             /* Read section start */
1776             section_id = qemu_get_be32(f);
1777             len = qemu_get_byte(f);
1778             qemu_get_buffer(f, (uint8_t *)idstr, len);
1779             idstr[len] = 0;
1780             instance_id = qemu_get_be32(f);
1781             version_id = qemu_get_be32(f);
1782
1783             /* Find savevm section */
1784             se = find_se(idstr, instance_id);
1785             if (se == NULL) {
1786                 fprintf(stderr, "Unknown savevm section or instance '%s' %d\n", idstr, instance_id);
1787                 ret = -EINVAL;
1788                 goto out;
1789             }
1790
1791             /* Validate version */
1792             if (version_id > se->version_id) {
1793                 fprintf(stderr, "savevm: unsupported version %d for '%s' v%d\n",
1794                         version_id, idstr, se->version_id);
1795                 ret = -EINVAL;
1796                 goto out;
1797             }
1798
1799             /* Add entry */
1800             le = g_malloc0(sizeof(*le));
1801
1802             le->se = se;
1803             le->section_id = section_id;
1804             le->version_id = version_id;
1805             QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
1806
1807             ret = vmstate_load(f, le->se, le->version_id);
1808             if (ret < 0) {
1809                 fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
1810                         instance_id, idstr);
1811                 goto out;
1812             }
1813             break;
1814         case QEMU_VM_SECTION_PART:
1815         case QEMU_VM_SECTION_END:
1816             section_id = qemu_get_be32(f);
1817
1818             QLIST_FOREACH(le, &loadvm_handlers, entry) {
1819                 if (le->section_id == section_id) {
1820                     break;
1821                 }
1822             }
1823             if (le == NULL) {
1824                 fprintf(stderr, "Unknown savevm section %d\n", section_id);
1825                 ret = -EINVAL;
1826                 goto out;
1827             }
1828
1829             ret = vmstate_load(f, le->se, le->version_id);
1830             if (ret < 0) {
1831                 fprintf(stderr, "qemu: warning: error while loading state section id %d\n",
1832                         section_id);
1833                 goto out;
1834             }
1835             break;
1836         default:
1837             fprintf(stderr, "Unknown savevm section type %d\n", section_type);
1838             ret = -EINVAL;
1839             goto out;
1840         }
1841     }
1842
1843     cpu_synchronize_all_post_init();
1844
1845     ret = 0;
1846
1847 out:
1848     QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
1849         QLIST_REMOVE(le, entry);
1850         g_free(le);
1851     }
1852
1853     if (qemu_file_has_error(f))
1854         ret = -EIO;
1855
1856     return ret;
1857 }
1858
1859 static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
1860                               const char *name)
1861 {
1862     QEMUSnapshotInfo *sn_tab, *sn;
1863     int nb_sns, i, ret;
1864
1865     ret = -ENOENT;
1866     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1867     if (nb_sns < 0)
1868         return ret;
1869     for(i = 0; i < nb_sns; i++) {
1870         sn = &sn_tab[i];
1871         if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
1872             *sn_info = *sn;
1873             ret = 0;
1874             break;
1875         }
1876     }
1877     g_free(sn_tab);
1878     return ret;
1879 }
1880
1881 /*
1882  * Deletes snapshots of a given name in all opened images.
1883  */
1884 static int del_existing_snapshots(Monitor *mon, const char *name)
1885 {
1886     BlockDriverState *bs;
1887     QEMUSnapshotInfo sn1, *snapshot = &sn1;
1888     int ret;
1889
1890     bs = NULL;
1891     while ((bs = bdrv_next(bs))) {
1892         if (bdrv_can_snapshot(bs) &&
1893             bdrv_snapshot_find(bs, snapshot, name) >= 0)
1894         {
1895             ret = bdrv_snapshot_delete(bs, name);
1896             if (ret < 0) {
1897                 monitor_printf(mon,
1898                                "Error while deleting snapshot on '%s'\n",
1899                                bdrv_get_device_name(bs));
1900                 return -1;
1901             }
1902         }
1903     }
1904
1905     return 0;
1906 }
1907
1908 void do_savevm(Monitor *mon, const QDict *qdict)
1909 {
1910     BlockDriverState *bs, *bs1;
1911     QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
1912     int ret;
1913     QEMUFile *f;
1914     int saved_vm_running;
1915     uint32_t vm_state_size;
1916 #ifdef _WIN32
1917     struct _timeb tb;
1918     struct tm *ptm;
1919 #else
1920     struct timeval tv;
1921     struct tm tm;
1922 #endif
1923     const char *name = qdict_get_try_str(qdict, "name");
1924
1925     /* Verify if there is a device that doesn't support snapshots and is writable */
1926     bs = NULL;
1927     while ((bs = bdrv_next(bs))) {
1928
1929         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
1930             continue;
1931         }
1932
1933         if (!bdrv_can_snapshot(bs)) {
1934             monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
1935                                bdrv_get_device_name(bs));
1936             return;
1937         }
1938     }
1939
1940     bs = bdrv_snapshots();
1941     if (!bs) {
1942         monitor_printf(mon, "No block device can accept snapshots\n");
1943         return;
1944     }
1945
1946     saved_vm_running = runstate_is_running();
1947     vm_stop(RUN_STATE_SAVE_VM);
1948
1949     memset(sn, 0, sizeof(*sn));
1950
1951     /* fill auxiliary fields */
1952 #ifdef _WIN32
1953     _ftime(&tb);
1954     sn->date_sec = tb.time;
1955     sn->date_nsec = tb.millitm * 1000000;
1956 #else
1957     gettimeofday(&tv, NULL);
1958     sn->date_sec = tv.tv_sec;
1959     sn->date_nsec = tv.tv_usec * 1000;
1960 #endif
1961     sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
1962
1963     if (name) {
1964         ret = bdrv_snapshot_find(bs, old_sn, name);
1965         if (ret >= 0) {
1966             pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
1967             pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
1968         } else {
1969             pstrcpy(sn->name, sizeof(sn->name), name);
1970         }
1971     } else {
1972 #ifdef _WIN32
1973         ptm = localtime(&tb.time);
1974         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", ptm);
1975 #else
1976         /* cast below needed for OpenBSD where tv_sec is still 'long' */
1977         localtime_r((const time_t *)&tv.tv_sec, &tm);
1978         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
1979 #endif
1980     }
1981
1982     /* Delete old snapshots of the same name */
1983     if (name && del_existing_snapshots(mon, name) < 0) {
1984         goto the_end;
1985     }
1986
1987     /* save the VM state */
1988     f = qemu_fopen_bdrv(bs, 1);
1989     if (!f) {
1990         monitor_printf(mon, "Could not open VM state file\n");
1991         goto the_end;
1992     }
1993     ret = qemu_savevm_state(mon, f);
1994     vm_state_size = qemu_ftell(f);
1995     qemu_fclose(f);
1996     if (ret < 0) {
1997         monitor_printf(mon, "Error %d while writing VM\n", ret);
1998         goto the_end;
1999     }
2000
2001     /* create the snapshots */
2002
2003     bs1 = NULL;
2004     while ((bs1 = bdrv_next(bs1))) {
2005         if (bdrv_can_snapshot(bs1)) {
2006             /* Write VM state size only to the image that contains the state */
2007             sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
2008             ret = bdrv_snapshot_create(bs1, sn);
2009             if (ret < 0) {
2010                 monitor_printf(mon, "Error while creating snapshot on '%s'\n",
2011                                bdrv_get_device_name(bs1));
2012             }
2013         }
2014     }
2015
2016  the_end:
2017     if (saved_vm_running)
2018         vm_start();
2019 }
2020
2021 int load_vmstate(const char *name)
2022 {
2023     BlockDriverState *bs, *bs_vm_state;
2024     QEMUSnapshotInfo sn;
2025     QEMUFile *f;
2026     int ret;
2027
2028     bs_vm_state = bdrv_snapshots();
2029     if (!bs_vm_state) {
2030         error_report("No block device supports snapshots");
2031         return -ENOTSUP;
2032     }
2033
2034     /* Don't even try to load empty VM states */
2035     ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
2036     if (ret < 0) {
2037         return ret;
2038     } else if (sn.vm_state_size == 0) {
2039         error_report("This is a disk-only snapshot. Revert to it offline "
2040             "using qemu-img.");
2041         return -EINVAL;
2042     }
2043
2044     /* Verify if there is any device that doesn't support snapshots and is
2045     writable and check if the requested snapshot is available too. */
2046     bs = NULL;
2047     while ((bs = bdrv_next(bs))) {
2048
2049         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2050             continue;
2051         }
2052
2053         if (!bdrv_can_snapshot(bs)) {
2054             error_report("Device '%s' is writable but does not support snapshots.",
2055                                bdrv_get_device_name(bs));
2056             return -ENOTSUP;
2057         }
2058
2059         ret = bdrv_snapshot_find(bs, &sn, name);
2060         if (ret < 0) {
2061             error_report("Device '%s' does not have the requested snapshot '%s'",
2062                            bdrv_get_device_name(bs), name);
2063             return ret;
2064         }
2065     }
2066
2067     /* Flush all IO requests so they don't interfere with the new state.  */
2068     qemu_aio_flush();
2069
2070     bs = NULL;
2071     while ((bs = bdrv_next(bs))) {
2072         if (bdrv_can_snapshot(bs)) {
2073             ret = bdrv_snapshot_goto(bs, name);
2074             if (ret < 0) {
2075                 error_report("Error %d while activating snapshot '%s' on '%s'",
2076                              ret, name, bdrv_get_device_name(bs));
2077                 return ret;
2078             }
2079         }
2080     }
2081
2082     /* restore the VM state */
2083     f = qemu_fopen_bdrv(bs_vm_state, 0);
2084     if (!f) {
2085         error_report("Could not open VM state file");
2086         return -EINVAL;
2087     }
2088
2089     qemu_system_reset(VMRESET_SILENT);
2090     ret = qemu_loadvm_state(f);
2091
2092     qemu_fclose(f);
2093     if (ret < 0) {
2094         error_report("Error %d while loading VM state", ret);
2095         return ret;
2096     }
2097
2098     return 0;
2099 }
2100
2101 void do_delvm(Monitor *mon, const QDict *qdict)
2102 {
2103     BlockDriverState *bs, *bs1;
2104     int ret;
2105     const char *name = qdict_get_str(qdict, "name");
2106
2107     bs = bdrv_snapshots();
2108     if (!bs) {
2109         monitor_printf(mon, "No block device supports snapshots\n");
2110         return;
2111     }
2112
2113     bs1 = NULL;
2114     while ((bs1 = bdrv_next(bs1))) {
2115         if (bdrv_can_snapshot(bs1)) {
2116             ret = bdrv_snapshot_delete(bs1, name);
2117             if (ret < 0) {
2118                 if (ret == -ENOTSUP)
2119                     monitor_printf(mon,
2120                                    "Snapshots not supported on device '%s'\n",
2121                                    bdrv_get_device_name(bs1));
2122                 else
2123                     monitor_printf(mon, "Error %d while deleting snapshot on "
2124                                    "'%s'\n", ret, bdrv_get_device_name(bs1));
2125             }
2126         }
2127     }
2128 }
2129
2130 void do_info_snapshots(Monitor *mon)
2131 {
2132     BlockDriverState *bs, *bs1;
2133     QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
2134     int nb_sns, i, ret, available;
2135     int total;
2136     int *available_snapshots;
2137     char buf[256];
2138
2139     bs = bdrv_snapshots();
2140     if (!bs) {
2141         monitor_printf(mon, "No available block device supports snapshots\n");
2142         return;
2143     }
2144
2145     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2146     if (nb_sns < 0) {
2147         monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
2148         return;
2149     }
2150
2151     if (nb_sns == 0) {
2152         monitor_printf(mon, "There is no snapshot available.\n");
2153         return;
2154     }
2155
2156     available_snapshots = g_malloc0(sizeof(int) * nb_sns);
2157     total = 0;
2158     for (i = 0; i < nb_sns; i++) {
2159         sn = &sn_tab[i];
2160         available = 1;
2161         bs1 = NULL;
2162
2163         while ((bs1 = bdrv_next(bs1))) {
2164             if (bdrv_can_snapshot(bs1) && bs1 != bs) {
2165                 ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
2166                 if (ret < 0) {
2167                     available = 0;
2168                     break;
2169                 }
2170             }
2171         }
2172
2173         if (available) {
2174             available_snapshots[total] = i;
2175             total++;
2176         }
2177     }
2178
2179     if (total > 0) {
2180         monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
2181         for (i = 0; i < total; i++) {
2182             sn = &sn_tab[available_snapshots[i]];
2183             monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
2184         }
2185     } else {
2186         monitor_printf(mon, "There is no suitable snapshot available\n");
2187     }
2188
2189     g_free(sn_tab);
2190     g_free(available_snapshots);
2191
2192 }