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 static void qemu_file_skip(QEMUFile *f, int size)
 536 {
 537     if (f->buf_index + size <= f->buf_size) {
 538         f->buf_index += size;
 539     }
 540 }
 541
 542 static int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset)
 543 {
 544     int pending;
 545     int index;
 546
 547     if (f->is_write) {
 548         abort();
 549     }
 550
 551     index = f->buf_index + offset;
 552     pending = f->buf_size - index;
 553     if (pending < size) {
 554         qemu_fill_buffer(f);
 555         index = f->buf_index + offset;
 556         pending = f->buf_size - index;
 557     }
 558
 559     if (pending <= 0) {
 560         return 0;
 561     }
 562     if (size > pending) {
 563         size = pending;
 564     }
 565
 566     memcpy(buf, f->buf + index, size);
 567     return size;
 568 }
 569
 570 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size)
 571 {
 572     int pending = size;
 573     int done = 0;
 574
 575     while (pending > 0) {
 576         int res;
 577
 578         res = qemu_peek_buffer(f, buf, pending, 0);
 579         if (res == 0) {
 580             return done;
 581         }
 582         qemu_file_skip(f, res);
 583         buf += res;
 584         pending -= res;
 585         done += res;
 586     }
 587     return done;
 588 }
 589
 590 static int qemu_peek_byte(QEMUFile *f, int offset)
 591 {
 592     int index = f->buf_index + offset;
 593
 594     if (f->is_write) {
 595         abort();
 596     }
 597
 598     if (index >= f->buf_size) {
 599         qemu_fill_buffer(f);
 600         index = f->buf_index + offset;
 601         if (index >= f->buf_size) {
 602             return 0;
 603         }
 604     }
 605     return f->buf[index];
 606 }
 607
 608 int qemu_get_byte(QEMUFile *f)
 609 {
 610     int result;
 611
 612     result = qemu_peek_byte(f, 0);
 613     qemu_file_skip(f, 1);
 614     return result;
 615 }
 616
 617 int64_t qemu_ftell(QEMUFile *f)
 618 {
 619     return f->buf_offset - f->buf_size + f->buf_index;
 620 }
 621
 622 int64_t qemu_fseek(QEMUFile *f, int64_t pos, int whence)
 623 {
 624     if (whence == SEEK_SET) {
 625         /* nothing to do */
 626     } else if (whence == SEEK_CUR) {
 627         pos += qemu_ftell(f);
 628     } else {
 629         /* SEEK_END not supported */
 630         return -1;
 631     }
 632     if (f->put_buffer) {
 633         qemu_fflush(f);
 634         f->buf_offset = pos;
 635     } else {
 636         f->buf_offset = pos;
 637         f->buf_index = 0;
 638         f->buf_size = 0;
 639     }
 640     return pos;
 641 }
 642
 643 int qemu_file_rate_limit(QEMUFile *f)
 644 {
 645     if (f->rate_limit)
 646         return f->rate_limit(f->opaque);
 647
 648     return 0;
 649 }
 650
 651 int64_t qemu_file_get_rate_limit(QEMUFile *f)
 652 {
 653     if (f->get_rate_limit)
 654         return f->get_rate_limit(f->opaque);
 655
 656     return 0;
 657 }
 658
 659 int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate)
 660 {
 661     /* any failed or completed migration keeps its state to allow probing of
 662      * migration data, but has no associated file anymore */
 663     if (f && f->set_rate_limit)
 664         return f->set_rate_limit(f->opaque, new_rate);
 665
 666     return 0;
 667 }
 668
 669 void qemu_put_be16(QEMUFile *f, unsigned int v)
 670 {
 671     qemu_put_byte(f, v >> 8);
 672     qemu_put_byte(f, v);
 673 }
 674
 675 void qemu_put_be32(QEMUFile *f, unsigned int v)
 676 {
 677     qemu_put_byte(f, v >> 24);
 678     qemu_put_byte(f, v >> 16);
 679     qemu_put_byte(f, v >> 8);
 680     qemu_put_byte(f, v);
 681 }
 682
 683 void qemu_put_be64(QEMUFile *f, uint64_t v)
 684 {
 685     qemu_put_be32(f, v >> 32);
 686     qemu_put_be32(f, v);
 687 }
 688
 689 unsigned int qemu_get_be16(QEMUFile *f)
 690 {
 691     unsigned int v;
 692     v = qemu_get_byte(f) << 8;
 693     v |= qemu_get_byte(f);
 694     return v;
 695 }
 696
 697 unsigned int qemu_get_be32(QEMUFile *f)
 698 {
 699     unsigned int v;
 700     v = qemu_get_byte(f) << 24;
 701     v |= qemu_get_byte(f) << 16;
 702     v |= qemu_get_byte(f) << 8;
 703     v |= qemu_get_byte(f);
 704     return v;
 705 }
 706
 707 uint64_t qemu_get_be64(QEMUFile *f)
 708 {
 709     uint64_t v;
 710     v = (uint64_t)qemu_get_be32(f) << 32;
 711     v |= qemu_get_be32(f);
 712     return v;
 713 }
 714
 715 /* bool */
 716
 717 static int get_bool(QEMUFile *f, void *pv, size_t size)
 718 {
 719     bool *v = pv;
 720     *v = qemu_get_byte(f);
 721     return 0;
 722 }
 723
 724 static void put_bool(QEMUFile *f, void *pv, size_t size)
 725 {
 726     bool *v = pv;
 727     qemu_put_byte(f, *v);
 728 }
 729
 730 const VMStateInfo vmstate_info_bool = {
 731     .name = "bool",
 732     .get  = get_bool,
 733     .put  = put_bool,
 734 };
 735
 736 /* 8 bit int */
 737
 738 static int get_int8(QEMUFile *f, void *pv, size_t size)
 739 {
 740     int8_t *v = pv;
 741     qemu_get_s8s(f, v);
 742     return 0;
 743 }
 744
 745 static void put_int8(QEMUFile *f, void *pv, size_t size)
 746 {
 747     int8_t *v = pv;
 748     qemu_put_s8s(f, v);
 749 }
 750
 751 const VMStateInfo vmstate_info_int8 = {
 752     .name = "int8",
 753     .get  = get_int8,
 754     .put  = put_int8,
 755 };
 756
 757 /* 16 bit int */
 758
 759 static int get_int16(QEMUFile *f, void *pv, size_t size)
 760 {
 761     int16_t *v = pv;
 762     qemu_get_sbe16s(f, v);
 763     return 0;
 764 }
 765
 766 static void put_int16(QEMUFile *f, void *pv, size_t size)
 767 {
 768     int16_t *v = pv;
 769     qemu_put_sbe16s(f, v);
 770 }
 771
 772 const VMStateInfo vmstate_info_int16 = {
 773     .name = "int16",
 774     .get  = get_int16,
 775     .put  = put_int16,
 776 };
 777
 778 /* 32 bit int */
 779
 780 static int get_int32(QEMUFile *f, void *pv, size_t size)
 781 {
 782     int32_t *v = pv;
 783     qemu_get_sbe32s(f, v);
 784     return 0;
 785 }
 786
 787 static void put_int32(QEMUFile *f, void *pv, size_t size)
 788 {
 789     int32_t *v = pv;
 790     qemu_put_sbe32s(f, v);
 791 }
 792
 793 const VMStateInfo vmstate_info_int32 = {
 794     .name = "int32",
 795     .get  = get_int32,
 796     .put  = put_int32,
 797 };
 798
 799 /* 32 bit int. See that the received value is the same than the one
 800    in the field */
 801
 802 static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
 803 {
 804     int32_t *v = pv;
 805     int32_t v2;
 806     qemu_get_sbe32s(f, &v2);
 807
 808     if (*v == v2)
 809         return 0;
 810     return -EINVAL;
 811 }
 812
 813 const VMStateInfo vmstate_info_int32_equal = {
 814     .name = "int32 equal",
 815     .get  = get_int32_equal,
 816     .put  = put_int32,
 817 };
 818
 819 /* 32 bit int. See that the received value is the less or the same
 820    than the one in the field */
 821
 822 static int get_int32_le(QEMUFile *f, void *pv, size_t size)
 823 {
 824     int32_t *old = pv;
 825     int32_t new;
 826     qemu_get_sbe32s(f, &new);
 827
 828     if (*old <= new)
 829         return 0;
 830     return -EINVAL;
 831 }
 832
 833 const VMStateInfo vmstate_info_int32_le = {
 834     .name = "int32 equal",
 835     .get  = get_int32_le,
 836     .put  = put_int32,
 837 };
 838
 839 /* 64 bit int */
 840
 841 static int get_int64(QEMUFile *f, void *pv, size_t size)
 842 {
 843     int64_t *v = pv;
 844     qemu_get_sbe64s(f, v);
 845     return 0;
 846 }
 847
 848 static void put_int64(QEMUFile *f, void *pv, size_t size)
 849 {
 850     int64_t *v = pv;
 851     qemu_put_sbe64s(f, v);
 852 }
 853
 854 const VMStateInfo vmstate_info_int64 = {
 855     .name = "int64",
 856     .get  = get_int64,
 857     .put  = put_int64,
 858 };
 859
 860 /* 8 bit unsigned int */
 861
 862 static int get_uint8(QEMUFile *f, void *pv, size_t size)
 863 {
 864     uint8_t *v = pv;
 865     qemu_get_8s(f, v);
 866     return 0;
 867 }
 868
 869 static void put_uint8(QEMUFile *f, void *pv, size_t size)
 870 {
 871     uint8_t *v = pv;
 872     qemu_put_8s(f, v);
 873 }
 874
 875 const VMStateInfo vmstate_info_uint8 = {
 876     .name = "uint8",
 877     .get  = get_uint8,
 878     .put  = put_uint8,
 879 };
 880
 881 /* 16 bit unsigned int */
 882
 883 static int get_uint16(QEMUFile *f, void *pv, size_t size)
 884 {
 885     uint16_t *v = pv;
 886     qemu_get_be16s(f, v);
 887     return 0;
 888 }
 889
 890 static void put_uint16(QEMUFile *f, void *pv, size_t size)
 891 {
 892     uint16_t *v = pv;
 893     qemu_put_be16s(f, v);
 894 }
 895
 896 const VMStateInfo vmstate_info_uint16 = {
 897     .name = "uint16",
 898     .get  = get_uint16,
 899     .put  = put_uint16,
 900 };
 901
 902 /* 32 bit unsigned int */
 903
 904 static int get_uint32(QEMUFile *f, void *pv, size_t size)
 905 {
 906     uint32_t *v = pv;
 907     qemu_get_be32s(f, v);
 908     return 0;
 909 }
 910
 911 static void put_uint32(QEMUFile *f, void *pv, size_t size)
 912 {
 913     uint32_t *v = pv;
 914     qemu_put_be32s(f, v);
 915 }
 916
 917 const VMStateInfo vmstate_info_uint32 = {
 918     .name = "uint32",
 919     .get  = get_uint32,
 920     .put  = put_uint32,
 921 };
 922
 923 /* 32 bit uint. See that the received value is the same than the one
 924    in the field */
 925
 926 static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
 927 {
 928     uint32_t *v = pv;
 929     uint32_t v2;
 930     qemu_get_be32s(f, &v2);
 931
 932     if (*v == v2) {
 933         return 0;
 934     }
 935     return -EINVAL;
 936 }
 937
 938 const VMStateInfo vmstate_info_uint32_equal = {
 939     .name = "uint32 equal",
 940     .get  = get_uint32_equal,
 941     .put  = put_uint32,
 942 };
 943
 944 /* 64 bit unsigned int */
 945
 946 static int get_uint64(QEMUFile *f, void *pv, size_t size)
 947 {
 948     uint64_t *v = pv;
 949     qemu_get_be64s(f, v);
 950     return 0;
 951 }
 952
 953 static void put_uint64(QEMUFile *f, void *pv, size_t size)
 954 {
 955     uint64_t *v = pv;
 956     qemu_put_be64s(f, v);
 957 }
 958
 959 const VMStateInfo vmstate_info_uint64 = {
 960     .name = "uint64",
 961     .get  = get_uint64,
 962     .put  = put_uint64,
 963 };
 964
 965 /* 8 bit int. See that the received value is the same than the one
 966    in the field */
 967
 968 static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
 969 {
 970     uint8_t *v = pv;
 971     uint8_t v2;
 972     qemu_get_8s(f, &v2);
 973
 974     if (*v == v2)
 975         return 0;
 976     return -EINVAL;
 977 }
 978
 979 const VMStateInfo vmstate_info_uint8_equal = {
 980     .name = "uint8 equal",
 981     .get  = get_uint8_equal,
 982     .put  = put_uint8,
 983 };
 984
 985 /* 16 bit unsigned int int. See that the received value is the same than the one
 986    in the field */
 987
 988 static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
 989 {
 990     uint16_t *v = pv;
 991     uint16_t v2;
 992     qemu_get_be16s(f, &v2);
 993
 994     if (*v == v2)
 995         return 0;
 996     return -EINVAL;
 997 }
 998
 999 const VMStateInfo vmstate_info_uint16_equal = {
1000     .name = "uint16 equal",
1001     .get  = get_uint16_equal,
1002     .put  = put_uint16,
1003 };
1004
1005 /* timers  */
1006
1007 static int get_timer(QEMUFile *f, void *pv, size_t size)
1008 {
1009     QEMUTimer *v = pv;
1010     qemu_get_timer(f, v);
1011     return 0;
1012 }
1013
1014 static void put_timer(QEMUFile *f, void *pv, size_t size)
1015 {
1016     QEMUTimer *v = pv;
1017     qemu_put_timer(f, v);
1018 }
1019
1020 const VMStateInfo vmstate_info_timer = {
1021     .name = "timer",
1022     .get  = get_timer,
1023     .put  = put_timer,
1024 };
1025
1026 /* uint8_t buffers */
1027
1028 static int get_buffer(QEMUFile *f, void *pv, size_t size)
1029 {
1030     uint8_t *v = pv;
1031     qemu_get_buffer(f, v, size);
1032     return 0;
1033 }
1034
1035 static void put_buffer(QEMUFile *f, void *pv, size_t size)
1036 {
1037     uint8_t *v = pv;
1038     qemu_put_buffer(f, v, size);
1039 }
1040
1041 const VMStateInfo vmstate_info_buffer = {
1042     .name = "buffer",
1043     .get  = get_buffer,
1044     .put  = put_buffer,
1045 };
1046
1047 /* unused buffers: space that was used for some fields that are
1048    not useful anymore */
1049
1050 static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
1051 {
1052     uint8_t buf[1024];
1053     int block_len;
1054
1055     while (size > 0) {
1056         block_len = MIN(sizeof(buf), size);
1057         size -= block_len;
1058         qemu_get_buffer(f, buf, block_len);
1059     }
1060    return 0;
1061 }
1062
1063 static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
1064 {
1065     static const uint8_t buf[1024];
1066     int block_len;
1067
1068     while (size > 0) {
1069         block_len = MIN(sizeof(buf), size);
1070         size -= block_len;
1071         qemu_put_buffer(f, buf, block_len);
1072     }
1073 }
1074
1075 const VMStateInfo vmstate_info_unused_buffer = {
1076     .name = "unused_buffer",
1077     .get  = get_unused_buffer,
1078     .put  = put_unused_buffer,
1079 };
1080
1081 typedef struct CompatEntry {
1082     char idstr[256];
1083     int instance_id;
1084 } CompatEntry;
1085
1086 typedef struct SaveStateEntry {
1087     QTAILQ_ENTRY(SaveStateEntry) entry;
1088     char idstr[256];
1089     int instance_id;
1090     int alias_id;
1091     int version_id;
1092     int section_id;
1093     SaveSetParamsHandler *set_params;
1094     SaveLiveStateHandler *save_live_state;
1095     SaveStateHandler *save_state;
1096     LoadStateHandler *load_state;
1097     const VMStateDescription *vmsd;
1098     void *opaque;
1099     CompatEntry *compat;
1100     int no_migrate;
1101 } SaveStateEntry;
1102
1103
1104 static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
1105     QTAILQ_HEAD_INITIALIZER(savevm_handlers);
1106 static int global_section_id;
1107
1108 static int calculate_new_instance_id(const char *idstr)
1109 {
1110     SaveStateEntry *se;
1111     int instance_id = 0;
1112
1113     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1114         if (strcmp(idstr, se->idstr) == 0
1115             && instance_id <= se->instance_id) {
1116             instance_id = se->instance_id + 1;
1117         }
1118     }
1119     return instance_id;
1120 }
1121
1122 static int calculate_compat_instance_id(const char *idstr)
1123 {
1124     SaveStateEntry *se;
1125     int instance_id = 0;
1126
1127     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1128         if (!se->compat)
1129             continue;
1130
1131         if (strcmp(idstr, se->compat->idstr) == 0
1132             && instance_id <= se->compat->instance_id) {
1133             instance_id = se->compat->instance_id + 1;
1134         }
1135     }
1136     return instance_id;
1137 }
1138
1139 /* TODO: Individual devices generally have very little idea about the rest
1140    of the system, so instance_id should be removed/replaced.
1141    Meanwhile pass -1 as instance_id if you do not already have a clearly
1142    distinguishing id for all instances of your device class. */
1143 int register_savevm_live(DeviceState *dev,
1144                          const char *idstr,
1145                          int instance_id,
1146                          int version_id,
1147                          SaveSetParamsHandler *set_params,
1148                          SaveLiveStateHandler *save_live_state,
1149                          SaveStateHandler *save_state,
1150                          LoadStateHandler *load_state,
1151                          void *opaque)
1152 {
1153     SaveStateEntry *se;
1154
1155     se = g_malloc0(sizeof(SaveStateEntry));
1156     se->version_id = version_id;
1157     se->section_id = global_section_id++;
1158     se->set_params = set_params;
1159     se->save_live_state = save_live_state;
1160     se->save_state = save_state;
1161     se->load_state = load_state;
1162     se->opaque = opaque;
1163     se->vmsd = NULL;
1164     se->no_migrate = 0;
1165
1166     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1167         char *id = dev->parent_bus->info->get_dev_path(dev);
1168         if (id) {
1169             pstrcpy(se->idstr, sizeof(se->idstr), id);
1170             pstrcat(se->idstr, sizeof(se->idstr), "/");
1171             g_free(id);
1172
1173             se->compat = g_malloc0(sizeof(CompatEntry));
1174             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
1175             se->compat->instance_id = instance_id == -1 ?
1176                          calculate_compat_instance_id(idstr) : instance_id;
1177             instance_id = -1;
1178         }
1179     }
1180     pstrcat(se->idstr, sizeof(se->idstr), idstr);
1181
1182     if (instance_id == -1) {
1183         se->instance_id = calculate_new_instance_id(se->idstr);
1184     } else {
1185         se->instance_id = instance_id;
1186     }
1187     assert(!se->compat || se->instance_id == 0);
1188     /* add at the end of list */
1189     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1190     return 0;
1191 }
1192
1193 int register_savevm(DeviceState *dev,
1194                     const char *idstr,
1195                     int instance_id,
1196                     int version_id,
1197                     SaveStateHandler *save_state,
1198                     LoadStateHandler *load_state,
1199                     void *opaque)
1200 {
1201     return register_savevm_live(dev, idstr, instance_id, version_id,
1202                                 NULL, NULL, save_state, load_state, opaque);
1203 }
1204
1205 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
1206 {
1207     SaveStateEntry *se, *new_se;
1208     char id[256] = "";
1209
1210     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1211         char *path = dev->parent_bus->info->get_dev_path(dev);
1212         if (path) {
1213             pstrcpy(id, sizeof(id), path);
1214             pstrcat(id, sizeof(id), "/");
1215             g_free(path);
1216         }
1217     }
1218     pstrcat(id, sizeof(id), idstr);
1219
1220     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1221         if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1222             QTAILQ_REMOVE(&savevm_handlers, se, entry);
1223             if (se->compat) {
1224                 g_free(se->compat);
1225             }
1226             g_free(se);
1227         }
1228     }
1229 }
1230
1231 /* mark a device as not to be migrated, that is the device should be
1232    unplugged before migration */
1233 void register_device_unmigratable(DeviceState *dev, const char *idstr,
1234                                                             void *opaque)
1235 {
1236     SaveStateEntry *se;
1237     char id[256] = "";
1238
1239     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1240         char *path = dev->parent_bus->info->get_dev_path(dev);
1241         if (path) {
1242             pstrcpy(id, sizeof(id), path);
1243             pstrcat(id, sizeof(id), "/");
1244             g_free(path);
1245         }
1246     }
1247     pstrcat(id, sizeof(id), idstr);
1248
1249     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1250         if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1251             se->no_migrate = 1;
1252         }
1253     }
1254 }
1255
1256 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
1257                                    const VMStateDescription *vmsd,
1258                                    void *opaque, int alias_id,
1259                                    int required_for_version)
1260 {
1261     SaveStateEntry *se;
1262
1263     /* If this triggers, alias support can be dropped for the vmsd. */
1264     assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);
1265
1266     se = g_malloc0(sizeof(SaveStateEntry));
1267     se->version_id = vmsd->version_id;
1268     se->section_id = global_section_id++;
1269     se->save_live_state = NULL;
1270     se->save_state = NULL;
1271     se->load_state = NULL;
1272     se->opaque = opaque;
1273     se->vmsd = vmsd;
1274     se->alias_id = alias_id;
1275     se->no_migrate = vmsd->unmigratable;
1276
1277     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1278         char *id = dev->parent_bus->info->get_dev_path(dev);
1279         if (id) {
1280             pstrcpy(se->idstr, sizeof(se->idstr), id);
1281             pstrcat(se->idstr, sizeof(se->idstr), "/");
1282             g_free(id);
1283
1284             se->compat = g_malloc0(sizeof(CompatEntry));
1285             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
1286             se->compat->instance_id = instance_id == -1 ?
1287                          calculate_compat_instance_id(vmsd->name) : instance_id;
1288             instance_id = -1;
1289         }
1290     }
1291     pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
1292
1293     if (instance_id == -1) {
1294         se->instance_id = calculate_new_instance_id(se->idstr);
1295     } else {
1296         se->instance_id = instance_id;
1297     }
1298     assert(!se->compat || se->instance_id == 0);
1299     /* add at the end of list */
1300     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1301     return 0;
1302 }
1303
1304 int vmstate_register(DeviceState *dev, int instance_id,
1305                      const VMStateDescription *vmsd, void *opaque)
1306 {
1307     return vmstate_register_with_alias_id(dev, instance_id, vmsd,
1308                                           opaque, -1, 0);
1309 }
1310
1311 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
1312                         void *opaque)
1313 {
1314     SaveStateEntry *se, *new_se;
1315
1316     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1317         if (se->vmsd == vmsd && se->opaque == opaque) {
1318             QTAILQ_REMOVE(&savevm_handlers, se, entry);
1319             if (se->compat) {
1320                 g_free(se->compat);
1321             }
1322             g_free(se);
1323         }
1324     }
1325 }
1326
1327 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1328                                     void *opaque);
1329 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1330                                    void *opaque);
1331
1332 int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
1333                        void *opaque, int version_id)
1334 {
1335     VMStateField *field = vmsd->fields;
1336     int ret;
1337
1338     if (version_id > vmsd->version_id) {
1339         return -EINVAL;
1340     }
1341     if (version_id < vmsd->minimum_version_id_old) {
1342         return -EINVAL;
1343     }
1344     if  (version_id < vmsd->minimum_version_id) {
1345         return vmsd->load_state_old(f, opaque, version_id);
1346     }
1347     if (vmsd->pre_load) {
1348         int ret = vmsd->pre_load(opaque);
1349         if (ret)
1350             return ret;
1351     }
1352     while(field->name) {
1353         if ((field->field_exists &&
1354              field->field_exists(opaque, version_id)) ||
1355             (!field->field_exists &&
1356              field->version_id <= version_id)) {
1357             void *base_addr = opaque + field->offset;
1358             int i, n_elems = 1;
1359             int size = field->size;
1360
1361             if (field->flags & VMS_VBUFFER) {
1362                 size = *(int32_t *)(opaque+field->size_offset);
1363                 if (field->flags & VMS_MULTIPLY) {
1364                     size *= field->size;
1365                 }
1366             }
1367             if (field->flags & VMS_ARRAY) {
1368                 n_elems = field->num;
1369             } else if (field->flags & VMS_VARRAY_INT32) {
1370                 n_elems = *(int32_t *)(opaque+field->num_offset);
1371             } else if (field->flags & VMS_VARRAY_UINT32) {
1372                 n_elems = *(uint32_t *)(opaque+field->num_offset);
1373             } else if (field->flags & VMS_VARRAY_UINT16) {
1374                 n_elems = *(uint16_t *)(opaque+field->num_offset);
1375             } else if (field->flags & VMS_VARRAY_UINT8) {
1376                 n_elems = *(uint8_t *)(opaque+field->num_offset);
1377             }
1378             if (field->flags & VMS_POINTER) {
1379                 base_addr = *(void **)base_addr + field->start;
1380             }
1381             for (i = 0; i < n_elems; i++) {
1382                 void *addr = base_addr + size * i;
1383
1384                 if (field->flags & VMS_ARRAY_OF_POINTER) {
1385                     addr = *(void **)addr;
1386                 }
1387                 if (field->flags & VMS_STRUCT) {
1388                     ret = vmstate_load_state(f, field->vmsd, addr, field->vmsd->version_id);
1389                 } else {
1390                     ret = field->info->get(f, addr, size);
1391
1392                 }
1393                 if (ret < 0) {
1394                     return ret;
1395                 }
1396             }
1397         }
1398         field++;
1399     }
1400     ret = vmstate_subsection_load(f, vmsd, opaque);
1401     if (ret != 0) {
1402         return ret;
1403     }
1404     if (vmsd->post_load) {
1405         return vmsd->post_load(opaque, version_id);
1406     }
1407     return 0;
1408 }
1409
1410 void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
1411                         void *opaque)
1412 {
1413     VMStateField *field = vmsd->fields;
1414
1415     if (vmsd->pre_save) {
1416         vmsd->pre_save(opaque);
1417     }
1418     while(field->name) {
1419         if (!field->field_exists ||
1420             field->field_exists(opaque, vmsd->version_id)) {
1421             void *base_addr = opaque + field->offset;
1422             int i, n_elems = 1;
1423             int size = field->size;
1424
1425             if (field->flags & VMS_VBUFFER) {
1426                 size = *(int32_t *)(opaque+field->size_offset);
1427                 if (field->flags & VMS_MULTIPLY) {
1428                     size *= field->size;
1429                 }
1430             }
1431             if (field->flags & VMS_ARRAY) {
1432                 n_elems = field->num;
1433             } else if (field->flags & VMS_VARRAY_INT32) {
1434                 n_elems = *(int32_t *)(opaque+field->num_offset);
1435             } else if (field->flags & VMS_VARRAY_UINT16) {
1436                 n_elems = *(uint16_t *)(opaque+field->num_offset);
1437             } else if (field->flags & VMS_VARRAY_UINT8) {
1438                 n_elems = *(uint8_t *)(opaque+field->num_offset);
1439             }
1440             if (field->flags & VMS_POINTER) {
1441                 base_addr = *(void **)base_addr + field->start;
1442             }
1443             for (i = 0; i < n_elems; i++) {
1444                 void *addr = base_addr + size * i;
1445
1446                 if (field->flags & VMS_ARRAY_OF_POINTER) {
1447                     addr = *(void **)addr;
1448                 }
1449                 if (field->flags & VMS_STRUCT) {
1450                     vmstate_save_state(f, field->vmsd, addr);
1451                 } else {
1452                     field->info->put(f, addr, size);
1453                 }
1454             }
1455         }
1456         field++;
1457     }
1458     vmstate_subsection_save(f, vmsd, opaque);
1459 }
1460
1461 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
1462 {
1463     if (!se->vmsd) {         /* Old style */
1464         return se->load_state(f, se->opaque, version_id);
1465     }
1466     return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
1467 }
1468
1469 static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
1470 {
1471     if (!se->vmsd) {         /* Old style */
1472         se->save_state(f, se->opaque);
1473         return;
1474     }
1475     vmstate_save_state(f,se->vmsd, se->opaque);
1476 }
1477
1478 #define QEMU_VM_FILE_MAGIC           0x5145564d
1479 #define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
1480 #define QEMU_VM_FILE_VERSION         0x00000003
1481
1482 #define QEMU_VM_EOF                  0x00
1483 #define QEMU_VM_SECTION_START        0x01
1484 #define QEMU_VM_SECTION_PART         0x02
1485 #define QEMU_VM_SECTION_END          0x03
1486 #define QEMU_VM_SECTION_FULL         0x04
1487 #define QEMU_VM_SUBSECTION           0x05
1488
1489 bool qemu_savevm_state_blocked(Monitor *mon)
1490 {
1491     SaveStateEntry *se;
1492
1493     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1494         if (se->no_migrate) {
1495             monitor_printf(mon, "state blocked by non-migratable device '%s'\n",
1496                            se->idstr);
1497             return true;
1498         }
1499     }
1500     return false;
1501 }
1502
1503 int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable,
1504                             int shared)
1505 {
1506     SaveStateEntry *se;
1507
1508     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1509         if(se->set_params == NULL) {
1510             continue;
1511         }
1512         se->set_params(blk_enable, shared, se->opaque);
1513     }
1514
1515     qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1516     qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1517
1518     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1519         int len;
1520
1521         if (se->save_live_state == NULL)
1522             continue;
1523
1524         /* Section type */
1525         qemu_put_byte(f, QEMU_VM_SECTION_START);
1526         qemu_put_be32(f, se->section_id);
1527
1528         /* ID string */
1529         len = strlen(se->idstr);
1530         qemu_put_byte(f, len);
1531         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1532
1533         qemu_put_be32(f, se->instance_id);
1534         qemu_put_be32(f, se->version_id);
1535
1536         se->save_live_state(mon, f, QEMU_VM_SECTION_START, se->opaque);
1537     }
1538
1539     if (qemu_file_has_error(f)) {
1540         qemu_savevm_state_cancel(mon, f);
1541         return -EIO;
1542     }
1543
1544     return 0;
1545 }
1546
1547 int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f)
1548 {
1549     SaveStateEntry *se;
1550     int ret = 1;
1551
1552     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1553         if (se->save_live_state == NULL)
1554             continue;
1555
1556         /* Section type */
1557         qemu_put_byte(f, QEMU_VM_SECTION_PART);
1558         qemu_put_be32(f, se->section_id);
1559
1560         ret = se->save_live_state(mon, f, QEMU_VM_SECTION_PART, se->opaque);
1561         if (!ret) {
1562             /* Do not proceed to the next vmstate before this one reported
1563                completion of the current stage. This serializes the migration
1564                and reduces the probability that a faster changing state is
1565                synchronized over and over again. */
1566             break;
1567         }
1568     }
1569
1570     if (ret)
1571         return 1;
1572
1573     if (qemu_file_has_error(f)) {
1574         qemu_savevm_state_cancel(mon, f);
1575         return -EIO;
1576     }
1577
1578     return 0;
1579 }
1580
1581 int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f)
1582 {
1583     SaveStateEntry *se;
1584
1585     cpu_synchronize_all_states();
1586
1587     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1588         if (se->save_live_state == NULL)
1589             continue;
1590
1591         /* Section type */
1592         qemu_put_byte(f, QEMU_VM_SECTION_END);
1593         qemu_put_be32(f, se->section_id);
1594
1595         se->save_live_state(mon, f, QEMU_VM_SECTION_END, se->opaque);
1596     }
1597
1598     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1599         int len;
1600
1601         if (se->save_state == NULL && se->vmsd == NULL)
1602             continue;
1603
1604         /* Section type */
1605         qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1606         qemu_put_be32(f, se->section_id);
1607
1608         /* ID string */
1609         len = strlen(se->idstr);
1610         qemu_put_byte(f, len);
1611         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1612
1613         qemu_put_be32(f, se->instance_id);
1614         qemu_put_be32(f, se->version_id);
1615
1616         vmstate_save(f, se);
1617     }
1618
1619     qemu_put_byte(f, QEMU_VM_EOF);
1620
1621     if (qemu_file_has_error(f))
1622         return -EIO;
1623
1624     return 0;
1625 }
1626
1627 void qemu_savevm_state_cancel(Monitor *mon, QEMUFile *f)
1628 {
1629     SaveStateEntry *se;
1630
1631     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1632         if (se->save_live_state) {
1633             se->save_live_state(mon, f, -1, se->opaque);
1634         }
1635     }
1636 }
1637
1638 static int qemu_savevm_state(Monitor *mon, QEMUFile *f)
1639 {
1640     int saved_vm_running;
1641     int ret;
1642
1643     saved_vm_running = runstate_is_running();
1644     vm_stop(RUN_STATE_SAVE_VM);
1645
1646     if (qemu_savevm_state_blocked(mon)) {
1647         ret = -EINVAL;
1648         goto out;
1649     }
1650
1651     ret = qemu_savevm_state_begin(mon, f, 0, 0);
1652     if (ret < 0)
1653         goto out;
1654
1655     do {
1656         ret = qemu_savevm_state_iterate(mon, f);
1657         if (ret < 0)
1658             goto out;
1659     } while (ret == 0);
1660
1661     ret = qemu_savevm_state_complete(mon, f);
1662
1663 out:
1664     if (qemu_file_has_error(f))
1665         ret = -EIO;
1666
1667     if (!ret && saved_vm_running)
1668         vm_start();
1669
1670     return ret;
1671 }
1672
1673 static SaveStateEntry *find_se(const char *idstr, int instance_id)
1674 {
1675     SaveStateEntry *se;
1676
1677     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1678         if (!strcmp(se->idstr, idstr) &&
1679             (instance_id == se->instance_id ||
1680              instance_id == se->alias_id))
1681             return se;
1682         /* Migrating from an older version? */
1683         if (strstr(se->idstr, idstr) && se->compat) {
1684             if (!strcmp(se->compat->idstr, idstr) &&
1685                 (instance_id == se->compat->instance_id ||
1686                  instance_id == se->alias_id))
1687                 return se;
1688         }
1689     }
1690     return NULL;
1691 }
1692
1693 static const VMStateDescription *vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
1694 {
1695     while(sub && sub->needed) {
1696         if (strcmp(idstr, sub->vmsd->name) == 0) {
1697             return sub->vmsd;
1698         }
1699         sub++;
1700     }
1701     return NULL;
1702 }
1703
1704 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1705                                    void *opaque)
1706 {
1707     const VMStateSubsection *sub = vmsd->subsections;
1708
1709     if (!sub || !sub->needed) {
1710         return 0;
1711     }
1712
1713     while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
1714         char idstr[256];
1715         int ret;
1716         uint8_t version_id, len, size;
1717         const VMStateDescription *sub_vmsd;
1718
1719         len = qemu_peek_byte(f, 1);
1720         if (len < strlen(vmsd->name) + 1) {
1721             /* subsection name has be be "section_name/a" */
1722             return 0;
1723         }
1724         size = qemu_peek_buffer(f, (uint8_t *)idstr, len, 2);
1725         if (size != len) {
1726             return 0;
1727         }
1728         idstr[size] = 0;
1729
1730         if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
1731             /* it don't have a valid subsection name */
1732             return 0;
1733         }
1734         sub_vmsd = vmstate_get_subsection(sub, idstr);
1735         if (sub_vmsd == NULL) {
1736             return -ENOENT;
1737         }
1738         qemu_file_skip(f, 1); /* subsection */
1739         qemu_file_skip(f, 1); /* len */
1740         qemu_file_skip(f, len); /* idstr */
1741         version_id = qemu_get_be32(f);
1742
1743         assert(!sub_vmsd->subsections);
1744         ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
1745         if (ret) {
1746             return ret;
1747         }
1748     }
1749     return 0;
1750 }
1751
1752 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1753                                     void *opaque)
1754 {
1755     const VMStateSubsection *sub = vmsd->subsections;
1756
1757     while (sub && sub->needed) {
1758         if (sub->needed(opaque)) {
1759             const VMStateDescription *vmsd = sub->vmsd;
1760             uint8_t len;
1761
1762             qemu_put_byte(f, QEMU_VM_SUBSECTION);
1763             len = strlen(vmsd->name);
1764             qemu_put_byte(f, len);
1765             qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
1766             qemu_put_be32(f, vmsd->version_id);
1767             assert(!vmsd->subsections);
1768             vmstate_save_state(f, vmsd, opaque);
1769         }
1770         sub++;
1771     }
1772 }
1773
1774 typedef struct LoadStateEntry {
1775     QLIST_ENTRY(LoadStateEntry) entry;
1776     SaveStateEntry *se;
1777     int section_id;
1778     int version_id;
1779 } LoadStateEntry;
1780
1781 int qemu_loadvm_state(QEMUFile *f)
1782 {
1783     QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
1784         QLIST_HEAD_INITIALIZER(loadvm_handlers);
1785     LoadStateEntry *le, *new_le;
1786     uint8_t section_type;
1787     unsigned int v;
1788     int ret;
1789
1790     if (qemu_savevm_state_blocked(default_mon)) {
1791         return -EINVAL;
1792     }
1793
1794     v = qemu_get_be32(f);
1795     if (v != QEMU_VM_FILE_MAGIC)
1796         return -EINVAL;
1797
1798     v = qemu_get_be32(f);
1799     if (v == QEMU_VM_FILE_VERSION_COMPAT) {
1800         fprintf(stderr, "SaveVM v2 format is obsolete and don't work anymore\n");
1801         return -ENOTSUP;
1802     }
1803     if (v != QEMU_VM_FILE_VERSION)
1804         return -ENOTSUP;
1805
1806     while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
1807         uint32_t instance_id, version_id, section_id;
1808         SaveStateEntry *se;
1809         char idstr[257];
1810         int len;
1811
1812         switch (section_type) {
1813         case QEMU_VM_SECTION_START:
1814         case QEMU_VM_SECTION_FULL:
1815             /* Read section start */
1816             section_id = qemu_get_be32(f);
1817             len = qemu_get_byte(f);
1818             qemu_get_buffer(f, (uint8_t *)idstr, len);
1819             idstr[len] = 0;
1820             instance_id = qemu_get_be32(f);
1821             version_id = qemu_get_be32(f);
1822
1823             /* Find savevm section */
1824             se = find_se(idstr, instance_id);
1825             if (se == NULL) {
1826                 fprintf(stderr, "Unknown savevm section or instance '%s' %d\n", idstr, instance_id);
1827                 ret = -EINVAL;
1828                 goto out;
1829             }
1830
1831             /* Validate version */
1832             if (version_id > se->version_id) {
1833                 fprintf(stderr, "savevm: unsupported version %d for '%s' v%d\n",
1834                         version_id, idstr, se->version_id);
1835                 ret = -EINVAL;
1836                 goto out;
1837             }
1838
1839             /* Add entry */
1840             le = g_malloc0(sizeof(*le));
1841
1842             le->se = se;
1843             le->section_id = section_id;
1844             le->version_id = version_id;
1845             QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
1846
1847             ret = vmstate_load(f, le->se, le->version_id);
1848             if (ret < 0) {
1849                 fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
1850                         instance_id, idstr);
1851                 goto out;
1852             }
1853             break;
1854         case QEMU_VM_SECTION_PART:
1855         case QEMU_VM_SECTION_END:
1856             section_id = qemu_get_be32(f);
1857
1858             QLIST_FOREACH(le, &loadvm_handlers, entry) {
1859                 if (le->section_id == section_id) {
1860                     break;
1861                 }
1862             }
1863             if (le == NULL) {
1864                 fprintf(stderr, "Unknown savevm section %d\n", section_id);
1865                 ret = -EINVAL;
1866                 goto out;
1867             }
1868
1869             ret = vmstate_load(f, le->se, le->version_id);
1870             if (ret < 0) {
1871                 fprintf(stderr, "qemu: warning: error while loading state section id %d\n",
1872                         section_id);
1873                 goto out;
1874             }
1875             break;
1876         default:
1877             fprintf(stderr, "Unknown savevm section type %d\n", section_type);
1878             ret = -EINVAL;
1879             goto out;
1880         }
1881     }
1882
1883     cpu_synchronize_all_post_init();
1884
1885     ret = 0;
1886
1887 out:
1888     QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
1889         QLIST_REMOVE(le, entry);
1890         g_free(le);
1891     }
1892
1893     if (qemu_file_has_error(f))
1894         ret = -EIO;
1895
1896     return ret;
1897 }
1898
1899 static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
1900                               const char *name)
1901 {
1902     QEMUSnapshotInfo *sn_tab, *sn;
1903     int nb_sns, i, ret;
1904
1905     ret = -ENOENT;
1906     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1907     if (nb_sns < 0)
1908         return ret;
1909     for(i = 0; i < nb_sns; i++) {
1910         sn = &sn_tab[i];
1911         if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
1912             *sn_info = *sn;
1913             ret = 0;
1914             break;
1915         }
1916     }
1917     g_free(sn_tab);
1918     return ret;
1919 }
1920
1921 /*
1922  * Deletes snapshots of a given name in all opened images.
1923  */
1924 static int del_existing_snapshots(Monitor *mon, const char *name)
1925 {
1926     BlockDriverState *bs;
1927     QEMUSnapshotInfo sn1, *snapshot = &sn1;
1928     int ret;
1929
1930     bs = NULL;
1931     while ((bs = bdrv_next(bs))) {
1932         if (bdrv_can_snapshot(bs) &&
1933             bdrv_snapshot_find(bs, snapshot, name) >= 0)
1934         {
1935             ret = bdrv_snapshot_delete(bs, name);
1936             if (ret < 0) {
1937                 monitor_printf(mon,
1938                                "Error while deleting snapshot on '%s'\n",
1939                                bdrv_get_device_name(bs));
1940                 return -1;
1941             }
1942         }
1943     }
1944
1945     return 0;
1946 }
1947
1948 void do_savevm(Monitor *mon, const QDict *qdict)
1949 {
1950     BlockDriverState *bs, *bs1;
1951     QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
1952     int ret;
1953     QEMUFile *f;
1954     int saved_vm_running;
1955     uint32_t vm_state_size;
1956 #ifdef _WIN32
1957     struct _timeb tb;
1958     struct tm *ptm;
1959 #else
1960     struct timeval tv;
1961     struct tm tm;
1962 #endif
1963     const char *name = qdict_get_try_str(qdict, "name");
1964
1965     /* Verify if there is a device that doesn't support snapshots and is writable */
1966     bs = NULL;
1967     while ((bs = bdrv_next(bs))) {
1968
1969         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
1970             continue;
1971         }
1972
1973         if (!bdrv_can_snapshot(bs)) {
1974             monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
1975                                bdrv_get_device_name(bs));
1976             return;
1977         }
1978     }
1979
1980     bs = bdrv_snapshots();
1981     if (!bs) {
1982         monitor_printf(mon, "No block device can accept snapshots\n");
1983         return;
1984     }
1985
1986     saved_vm_running = runstate_is_running();
1987     vm_stop(RUN_STATE_SAVE_VM);
1988
1989     memset(sn, 0, sizeof(*sn));
1990
1991     /* fill auxiliary fields */
1992 #ifdef _WIN32
1993     _ftime(&tb);
1994     sn->date_sec = tb.time;
1995     sn->date_nsec = tb.millitm * 1000000;
1996 #else
1997     gettimeofday(&tv, NULL);
1998     sn->date_sec = tv.tv_sec;
1999     sn->date_nsec = tv.tv_usec * 1000;
2000 #endif
2001     sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
2002
2003     if (name) {
2004         ret = bdrv_snapshot_find(bs, old_sn, name);
2005         if (ret >= 0) {
2006             pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
2007             pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
2008         } else {
2009             pstrcpy(sn->name, sizeof(sn->name), name);
2010         }
2011     } else {
2012 #ifdef _WIN32
2013         ptm = localtime(&tb.time);
2014         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", ptm);
2015 #else
2016         /* cast below needed for OpenBSD where tv_sec is still 'long' */
2017         localtime_r((const time_t *)&tv.tv_sec, &tm);
2018         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
2019 #endif
2020     }
2021
2022     /* Delete old snapshots of the same name */
2023     if (name && del_existing_snapshots(mon, name) < 0) {
2024         goto the_end;
2025     }
2026
2027     /* save the VM state */
2028     f = qemu_fopen_bdrv(bs, 1);
2029     if (!f) {
2030         monitor_printf(mon, "Could not open VM state file\n");
2031         goto the_end;
2032     }
2033     ret = qemu_savevm_state(mon, f);
2034     vm_state_size = qemu_ftell(f);
2035     qemu_fclose(f);
2036     if (ret < 0) {
2037         monitor_printf(mon, "Error %d while writing VM\n", ret);
2038         goto the_end;
2039     }
2040
2041     /* create the snapshots */
2042
2043     bs1 = NULL;
2044     while ((bs1 = bdrv_next(bs1))) {
2045         if (bdrv_can_snapshot(bs1)) {
2046             /* Write VM state size only to the image that contains the state */
2047             sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
2048             ret = bdrv_snapshot_create(bs1, sn);
2049             if (ret < 0) {
2050                 monitor_printf(mon, "Error while creating snapshot on '%s'\n",
2051                                bdrv_get_device_name(bs1));
2052             }
2053         }
2054     }
2055
2056  the_end:
2057     if (saved_vm_running)
2058         vm_start();
2059 }
2060
2061 int load_vmstate(const char *name)
2062 {
2063     BlockDriverState *bs, *bs_vm_state;
2064     QEMUSnapshotInfo sn;
2065     QEMUFile *f;
2066     int ret;
2067
2068     bs_vm_state = bdrv_snapshots();
2069     if (!bs_vm_state) {
2070         error_report("No block device supports snapshots");
2071         return -ENOTSUP;
2072     }
2073
2074     /* Don't even try to load empty VM states */
2075     ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
2076     if (ret < 0) {
2077         return ret;
2078     } else if (sn.vm_state_size == 0) {
2079         error_report("This is a disk-only snapshot. Revert to it offline "
2080             "using qemu-img.");
2081         return -EINVAL;
2082     }
2083
2084     /* Verify if there is any device that doesn't support snapshots and is
2085     writable and check if the requested snapshot is available too. */
2086     bs = NULL;
2087     while ((bs = bdrv_next(bs))) {
2088
2089         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2090             continue;
2091         }
2092
2093         if (!bdrv_can_snapshot(bs)) {
2094             error_report("Device '%s' is writable but does not support snapshots.",
2095                                bdrv_get_device_name(bs));
2096             return -ENOTSUP;
2097         }
2098
2099         ret = bdrv_snapshot_find(bs, &sn, name);
2100         if (ret < 0) {
2101             error_report("Device '%s' does not have the requested snapshot '%s'",
2102                            bdrv_get_device_name(bs), name);
2103             return ret;
2104         }
2105     }
2106
2107     /* Flush all IO requests so they don't interfere with the new state.  */
2108     qemu_aio_flush();
2109
2110     bs = NULL;
2111     while ((bs = bdrv_next(bs))) {
2112         if (bdrv_can_snapshot(bs)) {
2113             ret = bdrv_snapshot_goto(bs, name);
2114             if (ret < 0) {
2115                 error_report("Error %d while activating snapshot '%s' on '%s'",
2116                              ret, name, bdrv_get_device_name(bs));
2117                 return ret;
2118             }
2119         }
2120     }
2121
2122     /* restore the VM state */
2123     f = qemu_fopen_bdrv(bs_vm_state, 0);
2124     if (!f) {
2125         error_report("Could not open VM state file");
2126         return -EINVAL;
2127     }
2128
2129     qemu_system_reset(VMRESET_SILENT);
2130     ret = qemu_loadvm_state(f);
2131
2132     qemu_fclose(f);
2133     if (ret < 0) {
2134         error_report("Error %d while loading VM state", ret);
2135         return ret;
2136     }
2137
2138     return 0;
2139 }
2140
2141 void do_delvm(Monitor *mon, const QDict *qdict)
2142 {
2143     BlockDriverState *bs, *bs1;
2144     int ret;
2145     const char *name = qdict_get_str(qdict, "name");
2146
2147     bs = bdrv_snapshots();
2148     if (!bs) {
2149         monitor_printf(mon, "No block device supports snapshots\n");
2150         return;
2151     }
2152
2153     bs1 = NULL;
2154     while ((bs1 = bdrv_next(bs1))) {
2155         if (bdrv_can_snapshot(bs1)) {
2156             ret = bdrv_snapshot_delete(bs1, name);
2157             if (ret < 0) {
2158                 if (ret == -ENOTSUP)
2159                     monitor_printf(mon,
2160                                    "Snapshots not supported on device '%s'\n",
2161                                    bdrv_get_device_name(bs1));
2162                 else
2163                     monitor_printf(mon, "Error %d while deleting snapshot on "
2164                                    "'%s'\n", ret, bdrv_get_device_name(bs1));
2165             }
2166         }
2167     }
2168 }
2169
2170 void do_info_snapshots(Monitor *mon)
2171 {
2172     BlockDriverState *bs, *bs1;
2173     QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
2174     int nb_sns, i, ret, available;
2175     int total;
2176     int *available_snapshots;
2177     char buf[256];
2178
2179     bs = bdrv_snapshots();
2180     if (!bs) {
2181         monitor_printf(mon, "No available block device supports snapshots\n");
2182         return;
2183     }
2184
2185     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2186     if (nb_sns < 0) {
2187         monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
2188         return;
2189     }
2190
2191     if (nb_sns == 0) {
2192         monitor_printf(mon, "There is no snapshot available.\n");
2193         return;
2194     }
2195
2196     available_snapshots = g_malloc0(sizeof(int) * nb_sns);
2197     total = 0;
2198     for (i = 0; i < nb_sns; i++) {
2199         sn = &sn_tab[i];
2200         available = 1;
2201         bs1 = NULL;
2202
2203         while ((bs1 = bdrv_next(bs1))) {
2204             if (bdrv_can_snapshot(bs1) && bs1 != bs) {
2205                 ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
2206                 if (ret < 0) {
2207                     available = 0;
2208                     break;
2209                 }
2210             }
2211         }
2212
2213         if (available) {
2214             available_snapshots[total] = i;
2215             total++;
2216         }
2217     }
2218
2219     if (total > 0) {
2220         monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
2221         for (i = 0; i < total; i++) {
2222             sn = &sn_tab[available_snapshots[i]];
2223             monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
2224         }
2225     } else {
2226         monitor_printf(mon, "There is no suitable snapshot available\n");
2227     }
2228
2229     g_free(sn_tab);
2230     g_free(available_snapshots);
2231
2232 }