qemu/savevm.c
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   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 "qemu-timer.h"
  85#include "cpus.h"
  86
  87#define SELF_ANNOUNCE_ROUNDS 5
  88
  89#ifndef ETH_P_RARP
  90#define ETH_P_RARP 0x8035
  91#endif
  92#define ARP_HTYPE_ETH 0x0001
  93#define ARP_PTYPE_IP 0x0800
  94#define ARP_OP_REQUEST_REV 0x3
  95
  96static int announce_self_create(uint8_t *buf,
  97                                uint8_t *mac_addr)
  98{
  99    /* Ethernet header. */
 100    memset(buf, 0xff, 6);         /* destination MAC addr */
 101    memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
 102    *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */
 103
 104    /* RARP header. */
 105    *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
 106    *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
 107    *(buf + 18) = 6; /* hardware addr length (ethernet) */
 108    *(buf + 19) = 4; /* protocol addr length (IPv4) */
 109    *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
 110    memcpy(buf + 22, mac_addr, 6); /* source hw addr */
 111    memset(buf + 28, 0x00, 4);     /* source protocol addr */
 112    memcpy(buf + 32, mac_addr, 6); /* target hw addr */
 113    memset(buf + 38, 0x00, 4);     /* target protocol addr */
 114
 115    /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
 116    memset(buf + 42, 0x00, 18);
 117
 118    return 60; /* len (FCS will be added by hardware) */
 119}
 120
 121static void qemu_announce_self_iter(NICState *nic, void *opaque)
 122{
 123    uint8_t buf[60];
 124    int len;
 125
 126    len = announce_self_create(buf, nic->conf->macaddr.a);
 127
 128    qemu_send_packet_raw(&nic->nc, buf, len);
 129}
 130
 131
 132static void qemu_announce_self_once(void *opaque)
 133{
 134    static int count = SELF_ANNOUNCE_ROUNDS;
 135    QEMUTimer *timer = *(QEMUTimer **)opaque;
 136
 137    qemu_foreach_nic(qemu_announce_self_iter, NULL);
 138
 139    if (--count) {
 140        /* delay 50ms, 150ms, 250ms, ... */
 141        qemu_mod_timer(timer, qemu_get_clock_ms(rt_clock) +
 142                       50 + (SELF_ANNOUNCE_ROUNDS - count - 1) * 100);
 143    } else {
 144            qemu_del_timer(timer);
 145            qemu_free_timer(timer);
 146    }
 147}
 148
 149void qemu_announce_self(void)
 150{
 151        static QEMUTimer *timer;
 152        timer = qemu_new_timer_ms(rt_clock, qemu_announce_self_once, &timer);
 153        qemu_announce_self_once(&timer);
 154}
 155
 156/***********************************************************/
 157/* savevm/loadvm support */
 158
 159#define IO_BUF_SIZE 32768
 160
 161struct QEMUFile {
 162    QEMUFilePutBufferFunc *put_buffer;
 163    QEMUFileGetBufferFunc *get_buffer;
 164    QEMUFileCloseFunc *close;
 165    QEMUFileRateLimit *rate_limit;
 166    QEMUFileSetRateLimit *set_rate_limit;
 167    QEMUFileGetRateLimit *get_rate_limit;
 168    void *opaque;
 169    int is_write;
 170
 171    int64_t buf_offset; /* start of buffer when writing, end of buffer
 172                           when reading */
 173    int buf_index;
 174    int buf_size; /* 0 when writing */
 175    uint8_t buf[IO_BUF_SIZE];
 176
 177    int last_error;
 178};
 179
 180typedef struct QEMUFileStdio
 181{
 182    FILE *stdio_file;
 183    QEMUFile *file;
 184} QEMUFileStdio;
 185
 186typedef struct QEMUFileSocket
 187{
 188    int fd;
 189    QEMUFile *file;
 190} QEMUFileSocket;
 191
 192static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 193{
 194    QEMUFileSocket *s = opaque;
 195    ssize_t len;
 196
 197    do {
 198        len = qemu_recv(s->fd, buf, size, 0);
 199    } while (len == -1 && socket_error() == EINTR);
 200
 201    if (len == -1)
 202        len = -socket_error();
 203
 204    return len;
 205}
 206
 207static int socket_close(void *opaque)
 208{
 209    QEMUFileSocket *s = opaque;
 210    g_free(s);
 211    return 0;
 212}
 213
 214static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
 215{
 216    QEMUFileStdio *s = opaque;
 217    return fwrite(buf, 1, size, s->stdio_file);
 218}
 219
 220static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 221{
 222    QEMUFileStdio *s = opaque;
 223    FILE *fp = s->stdio_file;
 224    int bytes;
 225
 226    do {
 227        clearerr(fp);
 228        bytes = fread(buf, 1, size, fp);
 229    } while ((bytes == 0) && ferror(fp) && (errno == EINTR));
 230    return bytes;
 231}
 232
 233static int stdio_pclose(void *opaque)
 234{
 235    QEMUFileStdio *s = opaque;
 236    int ret;
 237    ret = pclose(s->stdio_file);
 238    g_free(s);
 239    return ret;
 240}
 241
 242static int stdio_fclose(void *opaque)
 243{
 244    QEMUFileStdio *s = opaque;
 245    fclose(s->stdio_file);
 246    g_free(s);
 247    return 0;
 248}
 249
 250QEMUFile *qemu_popen(FILE *stdio_file, const char *mode)
 251{
 252    QEMUFileStdio *s;
 253
 254    if (stdio_file == NULL || mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) {
 255        fprintf(stderr, "qemu_popen: Argument validity check failed\n");
 256        return NULL;
 257    }
 258
 259    s = g_malloc0(sizeof(QEMUFileStdio));
 260
 261    s->stdio_file = stdio_file;
 262
 263    if(mode[0] == 'r') {
 264        s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_pclose, 
 265                                 NULL, NULL, NULL);
 266    } else {
 267        s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_pclose, 
 268                                 NULL, NULL, NULL);
 269    }
 270    return s->file;
 271}
 272
 273QEMUFile *qemu_popen_cmd(const char *command, const char *mode)
 274{
 275    FILE *popen_file;
 276
 277    popen_file = popen(command, mode);
 278    if(popen_file == NULL) {
 279        return NULL;
 280    }
 281
 282    return qemu_popen(popen_file, mode);
 283}
 284
 285int qemu_stdio_fd(QEMUFile *f)
 286{
 287    QEMUFileStdio *p;
 288    int fd;
 289
 290    p = (QEMUFileStdio *)f->opaque;
 291    fd = fileno(p->stdio_file);
 292
 293    return fd;
 294}
 295
 296QEMUFile *qemu_fdopen(int fd, const char *mode)
 297{
 298    QEMUFileStdio *s;
 299
 300    if (mode == NULL ||
 301        (mode[0] != 'r' && mode[0] != 'w') ||
 302        mode[1] != 'b' || mode[2] != 0) {
 303        fprintf(stderr, "qemu_fdopen: Argument validity check failed\n");
 304        return NULL;
 305    }
 306
 307    s = g_malloc0(sizeof(QEMUFileStdio));
 308    s->stdio_file = fdopen(fd, mode);
 309    if (!s->stdio_file)
 310        goto fail;
 311
 312    if(mode[0] == 'r') {
 313        s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_fclose, 
 314                                 NULL, NULL, NULL);
 315    } else {
 316        s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_fclose, 
 317                                 NULL, NULL, NULL);
 318    }
 319    return s->file;
 320
 321fail:
 322    g_free(s);
 323    return NULL;
 324}
 325
 326QEMUFile *qemu_fopen_socket(int fd)
 327{
 328    QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
 329
 330    s->fd = fd;
 331    s->file = qemu_fopen_ops(s, NULL, socket_get_buffer, socket_close, 
 332                             NULL, NULL, NULL);
 333    return s->file;
 334}
 335
 336static int file_put_buffer(void *opaque, const uint8_t *buf,
 337                            int64_t pos, int size)
 338{
 339    QEMUFileStdio *s = opaque;
 340    fseek(s->stdio_file, pos, SEEK_SET);
 341    return fwrite(buf, 1, size, s->stdio_file);
 342}
 343
 344static int file_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 345{
 346    QEMUFileStdio *s = opaque;
 347    fseek(s->stdio_file, pos, SEEK_SET);
 348    return fread(buf, 1, size, s->stdio_file);
 349}
 350
 351QEMUFile *qemu_fopen(const char *filename, const char *mode)
 352{
 353    QEMUFileStdio *s;
 354
 355    if (mode == NULL ||
 356        (mode[0] != 'r' && mode[0] != 'w') ||
 357        mode[1] != 'b' || mode[2] != 0) {
 358        fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
 359        return NULL;
 360    }
 361
 362    s = g_malloc0(sizeof(QEMUFileStdio));
 363
 364    s->stdio_file = fopen(filename, mode);
 365    if (!s->stdio_file)
 366        goto fail;
 367    
 368    if(mode[0] == 'w') {
 369        s->file = qemu_fopen_ops(s, file_put_buffer, NULL, stdio_fclose, 
 370                                 NULL, NULL, NULL);
 371    } else {
 372        s->file = qemu_fopen_ops(s, NULL, file_get_buffer, stdio_fclose, 
 373                               NULL, NULL, NULL);
 374    }
 375    return s->file;
 376fail:
 377    g_free(s);
 378    return NULL;
 379}
 380
 381static int block_put_buffer(void *opaque, const uint8_t *buf,
 382                           int64_t pos, int size)
 383{
 384    bdrv_save_vmstate(opaque, buf, pos, size);
 385    return size;
 386}
 387
 388static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 389{
 390    return bdrv_load_vmstate(opaque, buf, pos, size);
 391}
 392
 393static int bdrv_fclose(void *opaque)
 394{
 395    return 0;
 396}
 397
 398static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
 399{
 400    if (is_writable)
 401        return qemu_fopen_ops(bs, block_put_buffer, NULL, bdrv_fclose, 
 402                              NULL, NULL, NULL);
 403    return qemu_fopen_ops(bs, NULL, block_get_buffer, bdrv_fclose, NULL, NULL, NULL);
 404}
 405
 406QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer,
 407                         QEMUFileGetBufferFunc *get_buffer,
 408                         QEMUFileCloseFunc *close,
 409                         QEMUFileRateLimit *rate_limit,
 410                         QEMUFileSetRateLimit *set_rate_limit,
 411                         QEMUFileGetRateLimit *get_rate_limit)
 412{
 413    QEMUFile *f;
 414
 415    f = g_malloc0(sizeof(QEMUFile));
 416
 417    f->opaque = opaque;
 418    f->put_buffer = put_buffer;
 419    f->get_buffer = get_buffer;
 420    f->close = close;
 421    f->rate_limit = rate_limit;
 422    f->set_rate_limit = set_rate_limit;
 423    f->get_rate_limit = get_rate_limit;
 424    f->is_write = 0;
 425
 426    return f;
 427}
 428
 429int qemu_file_get_error(QEMUFile *f)
 430{
 431    return f->last_error;
 432}
 433
 434void qemu_file_set_error(QEMUFile *f, int ret)
 435{
 436    f->last_error = ret;
 437}
 438
 439void qemu_fflush(QEMUFile *f)
 440{
 441    if (!f->put_buffer)
 442        return;
 443
 444    if (f->is_write && f->buf_index > 0) {
 445        int len;
 446
 447        len = f->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index);
 448        if (len > 0)
 449            f->buf_offset += f->buf_index;
 450        else
 451            f->last_error = -EINVAL;
 452        f->buf_index = 0;
 453    }
 454}
 455
 456static void qemu_fill_buffer(QEMUFile *f)
 457{
 458    int len;
 459    int pending;
 460
 461    if (!f->get_buffer)
 462        return;
 463
 464    if (f->is_write)
 465        abort();
 466
 467    pending = f->buf_size - f->buf_index;
 468    if (pending > 0) {
 469        memmove(f->buf, f->buf + f->buf_index, pending);
 470    }
 471    f->buf_index = 0;
 472    f->buf_size = pending;
 473
 474    len = f->get_buffer(f->opaque, f->buf + pending, f->buf_offset,
 475                        IO_BUF_SIZE - pending);
 476    if (len > 0) {
 477        f->buf_size += len;
 478        f->buf_offset += len;
 479    } else if (len == 0) {
 480        f->last_error = -EIO;
 481    } else if (len != -EAGAIN)
 482        f->last_error = len;
 483}
 484
 485int qemu_fclose(QEMUFile *f)
 486{
 487    int ret = 0;
 488    qemu_fflush(f);
 489    if (f->close)
 490        ret = f->close(f->opaque);
 491    g_free(f);
 492    return ret;
 493}
 494
 495void qemu_file_put_notify(QEMUFile *f)
 496{
 497    f->put_buffer(f->opaque, NULL, 0, 0);
 498}
 499
 500void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
 501{
 502    int l;
 503
 504    if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
 505        fprintf(stderr,
 506                "Attempted to write to buffer while read buffer is not empty\n");
 507        abort();
 508    }
 509
 510    while (!f->last_error && size > 0) {
 511        l = IO_BUF_SIZE - f->buf_index;
 512        if (l > size)
 513            l = size;
 514        memcpy(f->buf + f->buf_index, buf, l);
 515        f->is_write = 1;
 516        f->buf_index += l;
 517        buf += l;
 518        size -= l;
 519        if (f->buf_index >= IO_BUF_SIZE)
 520            qemu_fflush(f);
 521    }
 522}
 523
 524void qemu_put_byte(QEMUFile *f, int v)
 525{
 526    if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
 527        fprintf(stderr,
 528                "Attempted to write to buffer while read buffer is not empty\n");
 529        abort();
 530    }
 531
 532    f->buf[f->buf_index++] = v;
 533    f->is_write = 1;
 534    if (f->buf_index >= IO_BUF_SIZE)
 535        qemu_fflush(f);
 536}
 537
 538static void qemu_file_skip(QEMUFile *f, int size)
 539{
 540    if (f->buf_index + size <= f->buf_size) {
 541        f->buf_index += size;
 542    }
 543}
 544
 545static int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset)
 546{
 547    int pending;
 548    int index;
 549
 550    if (f->is_write) {
 551        abort();
 552    }
 553
 554    index = f->buf_index + offset;
 555    pending = f->buf_size - index;
 556    if (pending < size) {
 557        qemu_fill_buffer(f);
 558        index = f->buf_index + offset;
 559        pending = f->buf_size - index;
 560    }
 561
 562    if (pending <= 0) {
 563        return 0;
 564    }
 565    if (size > pending) {
 566        size = pending;
 567    }
 568
 569    memcpy(buf, f->buf + index, size);
 570    return size;
 571}
 572
 573int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size)
 574{
 575    int pending = size;
 576    int done = 0;
 577
 578    while (pending > 0) {
 579        int res;
 580
 581        res = qemu_peek_buffer(f, buf, pending, 0);
 582        if (res == 0) {
 583            return done;
 584        }
 585        qemu_file_skip(f, res);
 586        buf += res;
 587        pending -= res;
 588        done += res;
 589    }
 590    return done;
 591}
 592
 593static int qemu_peek_byte(QEMUFile *f, int offset)
 594{
 595    int index = f->buf_index + offset;
 596
 597    if (f->is_write) {
 598        abort();
 599    }
 600
 601    if (index >= f->buf_size) {
 602        qemu_fill_buffer(f);
 603        index = f->buf_index + offset;
 604        if (index >= f->buf_size) {
 605            return 0;
 606        }
 607    }
 608    return f->buf[index];
 609}
 610
 611int qemu_get_byte(QEMUFile *f)
 612{
 613    int result;
 614
 615    result = qemu_peek_byte(f, 0);
 616    qemu_file_skip(f, 1);
 617    return result;
 618}
 619
 620int64_t qemu_ftell(QEMUFile *f)
 621{
 622    return f->buf_offset - f->buf_size + f->buf_index;
 623}
 624
 625int64_t qemu_fseek(QEMUFile *f, int64_t pos, int whence)
 626{
 627    if (whence == SEEK_SET) {
 628        /* nothing to do */
 629    } else if (whence == SEEK_CUR) {
 630        pos += qemu_ftell(f);
 631    } else {
 632        /* SEEK_END not supported */
 633        return -1;
 634    }
 635    if (f->put_buffer) {
 636        qemu_fflush(f);
 637        f->buf_offset = pos;
 638    } else {
 639        f->buf_offset = pos;
 640        f->buf_index = 0;
 641        f->buf_size = 0;
 642    }
 643    return pos;
 644}
 645
 646int qemu_file_rate_limit(QEMUFile *f)
 647{
 648    if (f->rate_limit)
 649        return f->rate_limit(f->opaque);
 650
 651    return 0;
 652}
 653
 654int64_t qemu_file_get_rate_limit(QEMUFile *f)
 655{
 656    if (f->get_rate_limit)
 657        return f->get_rate_limit(f->opaque);
 658
 659    return 0;
 660}
 661
 662int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate)
 663{
 664    /* any failed or completed migration keeps its state to allow probing of
 665     * migration data, but has no associated file anymore */
 666    if (f && f->set_rate_limit)
 667        return f->set_rate_limit(f->opaque, new_rate);
 668
 669    return 0;
 670}
 671
 672void qemu_put_be16(QEMUFile *f, unsigned int v)
 673{
 674    qemu_put_byte(f, v >> 8);
 675    qemu_put_byte(f, v);
 676}
 677
 678void qemu_put_be32(QEMUFile *f, unsigned int v)
 679{
 680    qemu_put_byte(f, v >> 24);
 681    qemu_put_byte(f, v >> 16);
 682    qemu_put_byte(f, v >> 8);
 683    qemu_put_byte(f, v);
 684}
 685
 686void qemu_put_be64(QEMUFile *f, uint64_t v)
 687{
 688    qemu_put_be32(f, v >> 32);
 689    qemu_put_be32(f, v);
 690}
 691
 692unsigned int qemu_get_be16(QEMUFile *f)
 693{
 694    unsigned int v;
 695    v = qemu_get_byte(f) << 8;
 696    v |= qemu_get_byte(f);
 697    return v;
 698}
 699
 700unsigned int qemu_get_be32(QEMUFile *f)
 701{
 702    unsigned int v;
 703    v = qemu_get_byte(f) << 24;
 704    v |= qemu_get_byte(f) << 16;
 705    v |= qemu_get_byte(f) << 8;
 706    v |= qemu_get_byte(f);
 707    return v;
 708}
 709
 710uint64_t qemu_get_be64(QEMUFile *f)
 711{
 712    uint64_t v;
 713    v = (uint64_t)qemu_get_be32(f) << 32;
 714    v |= qemu_get_be32(f);
 715    return v;
 716}
 717
 718
 719/* timer */
 720
 721void qemu_put_timer(QEMUFile *f, QEMUTimer *ts)
 722{
 723    uint64_t expire_time;
 724
 725    expire_time = qemu_timer_expire_time_ns(ts);
 726    qemu_put_be64(f, expire_time);
 727}
 728
 729void qemu_get_timer(QEMUFile *f, QEMUTimer *ts)
 730{
 731    uint64_t expire_time;
 732
 733    expire_time = qemu_get_be64(f);
 734    if (expire_time != -1) {
 735        qemu_mod_timer_ns(ts, expire_time);
 736    } else {
 737        qemu_del_timer(ts);
 738    }
 739}
 740
 741
 742/* bool */
 743
 744static int get_bool(QEMUFile *f, void *pv, size_t size)
 745{
 746    bool *v = pv;
 747    *v = qemu_get_byte(f);
 748    return 0;
 749}
 750
 751static void put_bool(QEMUFile *f, void *pv, size_t size)
 752{
 753    bool *v = pv;
 754    qemu_put_byte(f, *v);
 755}
 756
 757const VMStateInfo vmstate_info_bool = {
 758    .name = "bool",
 759    .get  = get_bool,
 760    .put  = put_bool,
 761};
 762
 763/* 8 bit int */
 764
 765static int get_int8(QEMUFile *f, void *pv, size_t size)
 766{
 767    int8_t *v = pv;
 768    qemu_get_s8s(f, v);
 769    return 0;
 770}
 771
 772static void put_int8(QEMUFile *f, void *pv, size_t size)
 773{
 774    int8_t *v = pv;
 775    qemu_put_s8s(f, v);
 776}
 777
 778const VMStateInfo vmstate_info_int8 = {
 779    .name = "int8",
 780    .get  = get_int8,
 781    .put  = put_int8,
 782};
 783
 784/* 16 bit int */
 785
 786static int get_int16(QEMUFile *f, void *pv, size_t size)
 787{
 788    int16_t *v = pv;
 789    qemu_get_sbe16s(f, v);
 790    return 0;
 791}
 792
 793static void put_int16(QEMUFile *f, void *pv, size_t size)
 794{
 795    int16_t *v = pv;
 796    qemu_put_sbe16s(f, v);
 797}
 798
 799const VMStateInfo vmstate_info_int16 = {
 800    .name = "int16",
 801    .get  = get_int16,
 802    .put  = put_int16,
 803};
 804
 805/* 32 bit int */
 806
 807static int get_int32(QEMUFile *f, void *pv, size_t size)
 808{
 809    int32_t *v = pv;
 810    qemu_get_sbe32s(f, v);
 811    return 0;
 812}
 813
 814static void put_int32(QEMUFile *f, void *pv, size_t size)
 815{
 816    int32_t *v = pv;
 817    qemu_put_sbe32s(f, v);
 818}
 819
 820const VMStateInfo vmstate_info_int32 = {
 821    .name = "int32",
 822    .get  = get_int32,
 823    .put  = put_int32,
 824};
 825
 826/* 32 bit int. See that the received value is the same than the one
 827   in the field */
 828
 829static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
 830{
 831    int32_t *v = pv;
 832    int32_t v2;
 833    qemu_get_sbe32s(f, &v2);
 834
 835    if (*v == v2)
 836        return 0;
 837    return -EINVAL;
 838}
 839
 840const VMStateInfo vmstate_info_int32_equal = {
 841    .name = "int32 equal",
 842    .get  = get_int32_equal,
 843    .put  = put_int32,
 844};
 845
 846/* 32 bit int. See that the received value is the less or the same
 847   than the one in the field */
 848
 849static int get_int32_le(QEMUFile *f, void *pv, size_t size)
 850{
 851    int32_t *old = pv;
 852    int32_t new;
 853    qemu_get_sbe32s(f, &new);
 854
 855    if (*old <= new)
 856        return 0;
 857    return -EINVAL;
 858}
 859
 860const VMStateInfo vmstate_info_int32_le = {
 861    .name = "int32 equal",
 862    .get  = get_int32_le,
 863    .put  = put_int32,
 864};
 865
 866/* 64 bit int */
 867
 868static int get_int64(QEMUFile *f, void *pv, size_t size)
 869{
 870    int64_t *v = pv;
 871    qemu_get_sbe64s(f, v);
 872    return 0;
 873}
 874
 875static void put_int64(QEMUFile *f, void *pv, size_t size)
 876{
 877    int64_t *v = pv;
 878    qemu_put_sbe64s(f, v);
 879}
 880
 881const VMStateInfo vmstate_info_int64 = {
 882    .name = "int64",
 883    .get  = get_int64,
 884    .put  = put_int64,
 885};
 886
 887/* 8 bit unsigned int */
 888
 889static int get_uint8(QEMUFile *f, void *pv, size_t size)
 890{
 891    uint8_t *v = pv;
 892    qemu_get_8s(f, v);
 893    return 0;
 894}
 895
 896static void put_uint8(QEMUFile *f, void *pv, size_t size)
 897{
 898    uint8_t *v = pv;
 899    qemu_put_8s(f, v);
 900}
 901
 902const VMStateInfo vmstate_info_uint8 = {
 903    .name = "uint8",
 904    .get  = get_uint8,
 905    .put  = put_uint8,
 906};
 907
 908/* 16 bit unsigned int */
 909
 910static int get_uint16(QEMUFile *f, void *pv, size_t size)
 911{
 912    uint16_t *v = pv;
 913    qemu_get_be16s(f, v);
 914    return 0;
 915}
 916
 917static void put_uint16(QEMUFile *f, void *pv, size_t size)
 918{
 919    uint16_t *v = pv;
 920    qemu_put_be16s(f, v);
 921}
 922
 923const VMStateInfo vmstate_info_uint16 = {
 924    .name = "uint16",
 925    .get  = get_uint16,
 926    .put  = put_uint16,
 927};
 928
 929/* 32 bit unsigned int */
 930
 931static int get_uint32(QEMUFile *f, void *pv, size_t size)
 932{
 933    uint32_t *v = pv;
 934    qemu_get_be32s(f, v);
 935    return 0;
 936}
 937
 938static void put_uint32(QEMUFile *f, void *pv, size_t size)
 939{
 940    uint32_t *v = pv;
 941    qemu_put_be32s(f, v);
 942}
 943
 944const VMStateInfo vmstate_info_uint32 = {
 945    .name = "uint32",
 946    .get  = get_uint32,
 947    .put  = put_uint32,
 948};
 949
 950/* 32 bit uint. See that the received value is the same than the one
 951   in the field */
 952
 953static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
 954{
 955    uint32_t *v = pv;
 956    uint32_t v2;
 957    qemu_get_be32s(f, &v2);
 958
 959    if (*v == v2) {
 960        return 0;
 961    }
 962    return -EINVAL;
 963}
 964
 965const VMStateInfo vmstate_info_uint32_equal = {
 966    .name = "uint32 equal",
 967    .get  = get_uint32_equal,
 968    .put  = put_uint32,
 969};
 970
 971/* 64 bit unsigned int */
 972
 973static int get_uint64(QEMUFile *f, void *pv, size_t size)
 974{
 975    uint64_t *v = pv;
 976    qemu_get_be64s(f, v);
 977    return 0;
 978}
 979
 980static void put_uint64(QEMUFile *f, void *pv, size_t size)
 981{
 982    uint64_t *v = pv;
 983    qemu_put_be64s(f, v);
 984}
 985
 986const VMStateInfo vmstate_info_uint64 = {
 987    .name = "uint64",
 988    .get  = get_uint64,
 989    .put  = put_uint64,
 990};
 991
 992/* 8 bit int. See that the received value is the same than the one
 993   in the field */
 994
 995static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
 996{
 997    uint8_t *v = pv;
 998    uint8_t v2;
 999    qemu_get_8s(f, &v2);
1000
1001    if (*v == v2)
1002        return 0;
1003    return -EINVAL;
1004}
1005
1006const VMStateInfo vmstate_info_uint8_equal = {
1007    .name = "uint8 equal",
1008    .get  = get_uint8_equal,
1009    .put  = put_uint8,
1010};
1011
1012/* 16 bit unsigned int int. See that the received value is the same than the one
1013   in the field */
1014
1015static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
1016{
1017    uint16_t *v = pv;
1018    uint16_t v2;
1019    qemu_get_be16s(f, &v2);
1020
1021    if (*v == v2)
1022        return 0;
1023    return -EINVAL;
1024}
1025
1026const VMStateInfo vmstate_info_uint16_equal = {
1027    .name = "uint16 equal",
1028    .get  = get_uint16_equal,
1029    .put  = put_uint16,
1030};
1031
1032/* timers  */
1033
1034static int get_timer(QEMUFile *f, void *pv, size_t size)
1035{
1036    QEMUTimer *v = pv;
1037    qemu_get_timer(f, v);
1038    return 0;
1039}
1040
1041static void put_timer(QEMUFile *f, void *pv, size_t size)
1042{
1043    QEMUTimer *v = pv;
1044    qemu_put_timer(f, v);
1045}
1046
1047const VMStateInfo vmstate_info_timer = {
1048    .name = "timer",
1049    .get  = get_timer,
1050    .put  = put_timer,
1051};
1052
1053/* uint8_t buffers */
1054
1055static int get_buffer(QEMUFile *f, void *pv, size_t size)
1056{
1057    uint8_t *v = pv;
1058    qemu_get_buffer(f, v, size);
1059    return 0;
1060}
1061
1062static void put_buffer(QEMUFile *f, void *pv, size_t size)
1063{
1064    uint8_t *v = pv;
1065    qemu_put_buffer(f, v, size);
1066}
1067
1068const VMStateInfo vmstate_info_buffer = {
1069    .name = "buffer",
1070    .get  = get_buffer,
1071    .put  = put_buffer,
1072};
1073
1074/* unused buffers: space that was used for some fields that are
1075   not useful anymore */
1076
1077static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
1078{
1079    uint8_t buf[1024];
1080    int block_len;
1081
1082    while (size > 0) {
1083        block_len = MIN(sizeof(buf), size);
1084        size -= block_len;
1085        qemu_get_buffer(f, buf, block_len);
1086    }
1087   return 0;
1088}
1089
1090static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
1091{
1092    static const uint8_t buf[1024];
1093    int block_len;
1094
1095    while (size > 0) {
1096        block_len = MIN(sizeof(buf), size);
1097        size -= block_len;
1098        qemu_put_buffer(f, buf, block_len);
1099    }
1100}
1101
1102const VMStateInfo vmstate_info_unused_buffer = {
1103    .name = "unused_buffer",
1104    .get  = get_unused_buffer,
1105    .put  = put_unused_buffer,
1106};
1107
1108typedef struct CompatEntry {
1109    char idstr[256];
1110    int instance_id;
1111} CompatEntry;
1112
1113typedef struct SaveStateEntry {
1114    QTAILQ_ENTRY(SaveStateEntry) entry;
1115    char idstr[256];
1116    int instance_id;
1117    int alias_id;
1118    int version_id;
1119    int section_id;
1120    SaveSetParamsHandler *set_params;
1121    SaveLiveStateHandler *save_live_state;
1122    SaveStateHandler *save_state;
1123    LoadStateHandler *load_state;
1124    const VMStateDescription *vmsd;
1125    void *opaque;
1126    CompatEntry *compat;
1127    int no_migrate;
1128} SaveStateEntry;
1129
1130
1131static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
1132    QTAILQ_HEAD_INITIALIZER(savevm_handlers);
1133static int global_section_id;
1134
1135static int calculate_new_instance_id(const char *idstr)
1136{
1137    SaveStateEntry *se;
1138    int instance_id = 0;
1139
1140    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1141        if (strcmp(idstr, se->idstr) == 0
1142            && instance_id <= se->instance_id) {
1143            instance_id = se->instance_id + 1;
1144        }
1145    }
1146    return instance_id;
1147}
1148
1149static int calculate_compat_instance_id(const char *idstr)
1150{
1151    SaveStateEntry *se;
1152    int instance_id = 0;
1153
1154    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1155        if (!se->compat)
1156            continue;
1157
1158        if (strcmp(idstr, se->compat->idstr) == 0
1159            && instance_id <= se->compat->instance_id) {
1160            instance_id = se->compat->instance_id + 1;
1161        }
1162    }
1163    return instance_id;
1164}
1165
1166/* TODO: Individual devices generally have very little idea about the rest
1167   of the system, so instance_id should be removed/replaced.
1168   Meanwhile pass -1 as instance_id if you do not already have a clearly
1169   distinguishing id for all instances of your device class. */
1170int register_savevm_live(DeviceState *dev,
1171                         const char *idstr,
1172                         int instance_id,
1173                         int version_id,
1174                         SaveSetParamsHandler *set_params,
1175                         SaveLiveStateHandler *save_live_state,
1176                         SaveStateHandler *save_state,
1177                         LoadStateHandler *load_state,
1178                         void *opaque)
1179{
1180    SaveStateEntry *se;
1181
1182    se = g_malloc0(sizeof(SaveStateEntry));
1183    se->version_id = version_id;
1184    se->section_id = global_section_id++;
1185    se->set_params = set_params;
1186    se->save_live_state = save_live_state;
1187    se->save_state = save_state;
1188    se->load_state = load_state;
1189    se->opaque = opaque;
1190    se->vmsd = NULL;
1191    se->no_migrate = 0;
1192
1193    if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1194        char *id = dev->parent_bus->info->get_dev_path(dev);
1195        if (id) {
1196            pstrcpy(se->idstr, sizeof(se->idstr), id);
1197            pstrcat(se->idstr, sizeof(se->idstr), "/");
1198            g_free(id);
1199
1200            se->compat = g_malloc0(sizeof(CompatEntry));
1201            pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
1202            se->compat->instance_id = instance_id == -1 ?
1203                         calculate_compat_instance_id(idstr) : instance_id;
1204            instance_id = -1;
1205        }
1206    }
1207    pstrcat(se->idstr, sizeof(se->idstr), idstr);
1208
1209    if (instance_id == -1) {
1210        se->instance_id = calculate_new_instance_id(se->idstr);
1211    } else {
1212        se->instance_id = instance_id;
1213    }
1214    assert(!se->compat || se->instance_id == 0);
1215    /* add at the end of list */
1216    QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1217    return 0;
1218}
1219
1220int register_savevm(DeviceState *dev,
1221                    const char *idstr,
1222                    int instance_id,
1223                    int version_id,
1224                    SaveStateHandler *save_state,
1225                    LoadStateHandler *load_state,
1226                    void *opaque)
1227{
1228    return register_savevm_live(dev, idstr, instance_id, version_id,
1229                                NULL, NULL, save_state, load_state, opaque);
1230}
1231
1232void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
1233{
1234    SaveStateEntry *se, *new_se;
1235    char id[256] = "";
1236
1237    if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1238        char *path = dev->parent_bus->info->get_dev_path(dev);
1239        if (path) {
1240            pstrcpy(id, sizeof(id), path);
1241            pstrcat(id, sizeof(id), "/");
1242            g_free(path);
1243        }
1244    }
1245    pstrcat(id, sizeof(id), idstr);
1246
1247    QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1248        if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1249            QTAILQ_REMOVE(&savevm_handlers, se, entry);
1250            if (se->compat) {
1251                g_free(se->compat);
1252            }
1253            g_free(se);
1254        }
1255    }
1256}
1257
1258int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
1259                                   const VMStateDescription *vmsd,
1260                                   void *opaque, int alias_id,
1261                                   int required_for_version)
1262{
1263    SaveStateEntry *se;
1264
1265    /* If this triggers, alias support can be dropped for the vmsd. */
1266    assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);
1267
1268    se = g_malloc0(sizeof(SaveStateEntry));
1269    se->version_id = vmsd->version_id;
1270    se->section_id = global_section_id++;
1271    se->save_live_state = NULL;
1272    se->save_state = NULL;
1273    se->load_state = NULL;
1274    se->opaque = opaque;
1275    se->vmsd = vmsd;
1276    se->alias_id = alias_id;
1277    se->no_migrate = vmsd->unmigratable;
1278
1279    if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1280        char *id = dev->parent_bus->info->get_dev_path(dev);
1281        if (id) {
1282            pstrcpy(se->idstr, sizeof(se->idstr), id);
1283            pstrcat(se->idstr, sizeof(se->idstr), "/");
1284            g_free(id);
1285
1286            se->compat = g_malloc0(sizeof(CompatEntry));
1287            pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
1288            se->compat->instance_id = instance_id == -1 ?
1289                         calculate_compat_instance_id(vmsd->name) : instance_id;
1290            instance_id = -1;
1291        }
1292    }
1293    pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
1294
1295    if (instance_id == -1) {
1296        se->instance_id = calculate_new_instance_id(se->idstr);
1297    } else {
1298        se->instance_id = instance_id;
1299    }
1300    assert(!se->compat || se->instance_id == 0);
1301    /* add at the end of list */
1302    QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1303    return 0;
1304}
1305
1306int vmstate_register(DeviceState *dev, int instance_id,
1307                     const VMStateDescription *vmsd, void *opaque)
1308{
1309    return vmstate_register_with_alias_id(dev, instance_id, vmsd,
1310                                          opaque, -1, 0);
1311}
1312
1313void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
1314                        void *opaque)
1315{
1316    SaveStateEntry *se, *new_se;
1317
1318    QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1319        if (se->vmsd == vmsd && se->opaque == opaque) {
1320            QTAILQ_REMOVE(&savevm_handlers, se, entry);
1321            if (se->compat) {
1322                g_free(se->compat);
1323            }
1324            g_free(se);
1325        }
1326    }
1327}
1328
1329static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1330                                    void *opaque);
1331static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1332                                   void *opaque);
1333
1334int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
1335                       void *opaque, int version_id)
1336{
1337    VMStateField *field = vmsd->fields;
1338    int ret;
1339
1340    if (version_id > vmsd->version_id) {
1341        return -EINVAL;
1342    }
1343    if (version_id < vmsd->minimum_version_id_old) {
1344        return -EINVAL;
1345    }
1346    if  (version_id < vmsd->minimum_version_id) {
1347        return vmsd->load_state_old(f, opaque, version_id);
1348    }
1349    if (vmsd->pre_load) {
1350        int ret = vmsd->pre_load(opaque);
1351        if (ret)
1352            return ret;
1353    }
1354    while(field->name) {
1355        if ((field->field_exists &&
1356             field->field_exists(opaque, version_id)) ||
1357            (!field->field_exists &&
1358             field->version_id <= version_id)) {
1359            void *base_addr = opaque + field->offset;
1360            int i, n_elems = 1;
1361            int size = field->size;
1362
1363            if (field->flags & VMS_VBUFFER) {
1364                size = *(int32_t *)(opaque+field->size_offset);
1365                if (field->flags & VMS_MULTIPLY) {
1366                    size *= field->size;
1367                }
1368            }
1369            if (field->flags & VMS_ARRAY) {
1370                n_elems = field->num;
1371            } else if (field->flags & VMS_VARRAY_INT32) {
1372                n_elems = *(int32_t *)(opaque+field->num_offset);
1373            } else if (field->flags & VMS_VARRAY_UINT32) {
1374                n_elems = *(uint32_t *)(opaque+field->num_offset);
1375            } else if (field->flags & VMS_VARRAY_UINT16) {
1376                n_elems = *(uint16_t *)(opaque+field->num_offset);
1377            } else if (field->flags & VMS_VARRAY_UINT8) {
1378                n_elems = *(uint8_t *)(opaque+field->num_offset);
1379            }
1380            if (field->flags & VMS_POINTER) {
1381                base_addr = *(void **)base_addr + field->start;
1382            }
1383            for (i = 0; i < n_elems; i++) {
1384                void *addr = base_addr + size * i;
1385
1386                if (field->flags & VMS_ARRAY_OF_POINTER) {
1387                    addr = *(void **)addr;
1388                }
1389                if (field->flags & VMS_STRUCT) {
1390                    ret = vmstate_load_state(f, field->vmsd, addr, field->vmsd->version_id);
1391                } else {
1392                    ret = field->info->get(f, addr, size);
1393
1394                }
1395                if (ret < 0) {
1396                    return ret;
1397                }
1398            }
1399        }
1400        field++;
1401    }
1402    ret = vmstate_subsection_load(f, vmsd, opaque);
1403    if (ret != 0) {
1404        return ret;
1405    }
1406    if (vmsd->post_load) {
1407        return vmsd->post_load(opaque, version_id);
1408    }
1409    return 0;
1410}
1411
1412void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
1413                        void *opaque)
1414{
1415    VMStateField *field = vmsd->fields;
1416
1417    if (vmsd->pre_save) {
1418        vmsd->pre_save(opaque);
1419    }
1420    while(field->name) {
1421        if (!field->field_exists ||
1422            field->field_exists(opaque, vmsd->version_id)) {
1423            void *base_addr = opaque + field->offset;
1424            int i, n_elems = 1;
1425            int size = field->size;
1426
1427            if (field->flags & VMS_VBUFFER) {
1428                size = *(int32_t *)(opaque+field->size_offset);
1429                if (field->flags & VMS_MULTIPLY) {
1430                    size *= field->size;
1431                }
1432            }
1433            if (field->flags & VMS_ARRAY) {
1434                n_elems = field->num;
1435            } else if (field->flags & VMS_VARRAY_INT32) {
1436                n_elems = *(int32_t *)(opaque+field->num_offset);
1437            } else if (field->flags & VMS_VARRAY_UINT16) {
1438                n_elems = *(uint16_t *)(opaque+field->num_offset);
1439            } else if (field->flags & VMS_VARRAY_UINT8) {
1440                n_elems = *(uint8_t *)(opaque+field->num_offset);
1441            }
1442            if (field->flags & VMS_POINTER) {
1443                base_addr = *(void **)base_addr + field->start;
1444            }
1445            for (i = 0; i < n_elems; i++) {
1446                void *addr = base_addr + size * i;
1447
1448                if (field->flags & VMS_ARRAY_OF_POINTER) {
1449                    addr = *(void **)addr;
1450                }
1451                if (field->flags & VMS_STRUCT) {
1452                    vmstate_save_state(f, field->vmsd, addr);
1453                } else {
1454                    field->info->put(f, addr, size);
1455                }
1456            }
1457        }
1458        field++;
1459    }
1460    vmstate_subsection_save(f, vmsd, opaque);
1461}
1462
1463static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
1464{
1465    if (!se->vmsd) {         /* Old style */
1466        return se->load_state(f, se->opaque, version_id);
1467    }
1468    return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
1469}
1470
1471static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
1472{
1473    if (!se->vmsd) {         /* Old style */
1474        se->save_state(f, se->opaque);
1475        return;
1476    }
1477    vmstate_save_state(f,se->vmsd, se->opaque);
1478}
1479
1480#define QEMU_VM_FILE_MAGIC           0x5145564d
1481#define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
1482#define QEMU_VM_FILE_VERSION         0x00000003
1483
1484#define QEMU_VM_EOF                  0x00
1485#define QEMU_VM_SECTION_START        0x01
1486#define QEMU_VM_SECTION_PART         0x02
1487#define QEMU_VM_SECTION_END          0x03
1488#define QEMU_VM_SECTION_FULL         0x04
1489#define QEMU_VM_SUBSECTION           0x05
1490
1491bool qemu_savevm_state_blocked(Monitor *mon)
1492{
1493    SaveStateEntry *se;
1494
1495    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1496        if (se->no_migrate) {
1497            monitor_printf(mon, "state blocked by non-migratable device '%s'\n",
1498                           se->idstr);
1499            return true;
1500        }
1501    }
1502    return false;
1503}
1504
1505int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable,
1506                            int shared)
1507{
1508    SaveStateEntry *se;
1509    int ret;
1510
1511    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1512        if(se->set_params == NULL) {
1513            continue;
1514        }
1515        se->set_params(blk_enable, shared, se->opaque);
1516    }
1517    
1518    qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1519    qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1520
1521    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1522        int len;
1523
1524        if (se->save_live_state == NULL)
1525            continue;
1526
1527        /* Section type */
1528        qemu_put_byte(f, QEMU_VM_SECTION_START);
1529        qemu_put_be32(f, se->section_id);
1530
1531        /* ID string */
1532        len = strlen(se->idstr);
1533        qemu_put_byte(f, len);
1534        qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1535
1536        qemu_put_be32(f, se->instance_id);
1537        qemu_put_be32(f, se->version_id);
1538
1539        ret = se->save_live_state(mon, f, QEMU_VM_SECTION_START, se->opaque);
1540        if (ret < 0) {
1541            qemu_savevm_state_cancel(mon, f);
1542            return ret;
1543        }
1544    }
1545    ret = qemu_file_get_error(f);
1546    if (ret != 0) {
1547        qemu_savevm_state_cancel(mon, f);
1548    }
1549
1550    return ret;
1551
1552}
1553
1554/*
1555 * this funtion has three return values:
1556 *   negative: there was one error, and we have -errno.
1557 *   0 : We haven't finished, caller have to go again
1558 *   1 : We have finished, we can go to complete phase
1559 */
1560int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f)
1561{
1562    SaveStateEntry *se;
1563    int ret = 1;
1564
1565    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1566        if (se->save_live_state == NULL)
1567            continue;
1568
1569        /* Section type */
1570        qemu_put_byte(f, QEMU_VM_SECTION_PART);
1571        qemu_put_be32(f, se->section_id);
1572
1573        ret = se->save_live_state(mon, f, QEMU_VM_SECTION_PART, se->opaque);
1574        if (ret <= 0) {
1575            /* Do not proceed to the next vmstate before this one reported
1576               completion of the current stage. This serializes the migration
1577               and reduces the probability that a faster changing state is
1578               synchronized over and over again. */
1579            break;
1580        }
1581    }
1582    if (ret != 0) {
1583        return ret;
1584    }
1585    ret = qemu_file_get_error(f);
1586    if (ret != 0) {
1587        qemu_savevm_state_cancel(mon, f);
1588    }
1589    return ret;
1590}
1591
1592int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f)
1593{
1594    SaveStateEntry *se;
1595    int ret;
1596
1597    cpu_synchronize_all_states();
1598
1599    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1600        if (se->save_live_state == NULL)
1601            continue;
1602
1603        /* Section type */
1604        qemu_put_byte(f, QEMU_VM_SECTION_END);
1605        qemu_put_be32(f, se->section_id);
1606
1607        ret = se->save_live_state(mon, f, QEMU_VM_SECTION_END, se->opaque);
1608        if (ret < 0) {
1609            return ret;
1610        }
1611    }
1612
1613    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1614        int len;
1615
1616        if (se->save_state == NULL && se->vmsd == NULL)
1617            continue;
1618
1619        /* Section type */
1620        qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1621        qemu_put_be32(f, se->section_id);
1622
1623        /* ID string */
1624        len = strlen(se->idstr);
1625        qemu_put_byte(f, len);
1626        qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1627
1628        qemu_put_be32(f, se->instance_id);
1629        qemu_put_be32(f, se->version_id);
1630
1631        vmstate_save(f, se);
1632    }
1633
1634    qemu_put_byte(f, QEMU_VM_EOF);
1635
1636    return qemu_file_get_error(f);
1637}
1638
1639void qemu_savevm_state_cancel(Monitor *mon, QEMUFile *f)
1640{
1641    SaveStateEntry *se;
1642
1643    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1644        if (se->save_live_state) {
1645            se->save_live_state(mon, f, -1, se->opaque);
1646        }
1647    }
1648}
1649
1650static int qemu_savevm_state(Monitor *mon, QEMUFile *f)
1651{
1652    int ret;
1653
1654    if (qemu_savevm_state_blocked(mon)) {
1655        ret = -EINVAL;
1656        goto out;
1657    }
1658
1659    ret = qemu_savevm_state_begin(mon, f, 0, 0);
1660    if (ret < 0)
1661        goto out;
1662
1663    do {
1664        ret = qemu_savevm_state_iterate(mon, f);
1665        if (ret < 0)
1666            goto out;
1667    } while (ret == 0);
1668
1669    ret = qemu_savevm_state_complete(mon, f);
1670
1671out:
1672    if (ret == 0) {
1673        ret = qemu_file_get_error(f);
1674    }
1675
1676    return ret;
1677}
1678
1679static SaveStateEntry *find_se(const char *idstr, int instance_id)
1680{
1681    SaveStateEntry *se;
1682
1683    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1684        if (!strcmp(se->idstr, idstr) &&
1685            (instance_id == se->instance_id ||
1686             instance_id == se->alias_id))
1687            return se;
1688        /* Migrating from an older version? */
1689        if (strstr(se->idstr, idstr) && se->compat) {
1690            if (!strcmp(se->compat->idstr, idstr) &&
1691                (instance_id == se->compat->instance_id ||
1692                 instance_id == se->alias_id))
1693                return se;
1694        }
1695    }
1696    return NULL;
1697}
1698
1699static const VMStateDescription *vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
1700{
1701    while(sub && sub->needed) {
1702        if (strcmp(idstr, sub->vmsd->name) == 0) {
1703            return sub->vmsd;
1704        }
1705        sub++;
1706    }
1707    return NULL;
1708}
1709
1710static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1711                                   void *opaque)
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(vmsd->subsections, 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        ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
1744        if (ret) {
1745            return ret;
1746        }
1747    }
1748    return 0;
1749}
1750
1751static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1752                                    void *opaque)
1753{
1754    const VMStateSubsection *sub = vmsd->subsections;
1755
1756    while (sub && sub->needed) {
1757        if (sub->needed(opaque)) {
1758            const VMStateDescription *vmsd = sub->vmsd;
1759            uint8_t len;
1760
1761            qemu_put_byte(f, QEMU_VM_SUBSECTION);
1762            len = strlen(vmsd->name);
1763            qemu_put_byte(f, len);
1764            qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
1765            qemu_put_be32(f, vmsd->version_id);
1766            vmstate_save_state(f, vmsd, opaque);
1767        }
1768        sub++;
1769    }
1770}
1771
1772typedef struct LoadStateEntry {
1773    QLIST_ENTRY(LoadStateEntry) entry;
1774    SaveStateEntry *se;
1775    int section_id;
1776    int version_id;
1777} LoadStateEntry;
1778
1779int qemu_loadvm_state(QEMUFile *f)
1780{
1781    QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
1782        QLIST_HEAD_INITIALIZER(loadvm_handlers);
1783    LoadStateEntry *le, *new_le;
1784    uint8_t section_type;
1785    unsigned int v;
1786    int ret;
1787
1788    if (qemu_savevm_state_blocked(default_mon)) {
1789        return -EINVAL;
1790    }
1791
1792    v = qemu_get_be32(f);
1793    if (v != QEMU_VM_FILE_MAGIC)
1794        return -EINVAL;
1795
1796    v = qemu_get_be32(f);
1797    if (v == QEMU_VM_FILE_VERSION_COMPAT) {
1798        fprintf(stderr, "SaveVM v2 format is obsolete and don't work anymore\n");
1799        return -ENOTSUP;
1800    }
1801    if (v != QEMU_VM_FILE_VERSION)
1802        return -ENOTSUP;
1803
1804    while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
1805        uint32_t instance_id, version_id, section_id;
1806        SaveStateEntry *se;
1807        char idstr[257];
1808        int len;
1809
1810        switch (section_type) {
1811        case QEMU_VM_SECTION_START:
1812        case QEMU_VM_SECTION_FULL:
1813            /* Read section start */
1814            section_id = qemu_get_be32(f);
1815            len = qemu_get_byte(f);
1816            qemu_get_buffer(f, (uint8_t *)idstr, len);
1817            idstr[len] = 0;
1818            instance_id = qemu_get_be32(f);
1819            version_id = qemu_get_be32(f);
1820
1821            /* Find savevm section */
1822            se = find_se(idstr, instance_id);
1823            if (se == NULL) {
1824                fprintf(stderr, "Unknown savevm section or instance '%s' %d\n", idstr, instance_id);
1825                ret = -EINVAL;
1826                goto out;
1827            }
1828
1829            /* Validate version */
1830            if (version_id > se->version_id) {
1831                fprintf(stderr, "savevm: unsupported version %d for '%s' v%d\n",
1832                        version_id, idstr, se->version_id);
1833                ret = -EINVAL;
1834                goto out;
1835            }
1836
1837            /* Add entry */
1838            le = g_malloc0(sizeof(*le));
1839
1840            le->se = se;
1841            le->section_id = section_id;
1842            le->version_id = version_id;
1843            QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
1844
1845            ret = vmstate_load(f, le->se, le->version_id);
1846            if (ret < 0) {
1847                fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
1848                        instance_id, idstr);
1849                goto out;
1850            }
1851            break;
1852        case QEMU_VM_SECTION_PART:
1853        case QEMU_VM_SECTION_END:
1854            section_id = qemu_get_be32(f);
1855
1856            QLIST_FOREACH(le, &loadvm_handlers, entry) {
1857                if (le->section_id == section_id) {
1858                    break;
1859                }
1860            }
1861            if (le == NULL) {
1862                fprintf(stderr, "Unknown savevm section %d\n", section_id);
1863                ret = -EINVAL;
1864                goto out;
1865            }
1866
1867            ret = vmstate_load(f, le->se, le->version_id);
1868            if (ret < 0) {
1869                fprintf(stderr, "qemu: warning: error while loading state section id %d\n",
1870                        section_id);
1871                goto out;
1872            }
1873            break;
1874        default:
1875            fprintf(stderr, "Unknown savevm section type %d\n", section_type);
1876            ret = -EINVAL;
1877            goto out;
1878        }
1879    }
1880
1881    cpu_synchronize_all_post_init();
1882
1883    ret = 0;
1884
1885out:
1886    QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
1887        QLIST_REMOVE(le, entry);
1888        g_free(le);
1889    }
1890
1891    if (ret == 0) {
1892        ret = qemu_file_get_error(f);
1893    }
1894
1895    return ret;
1896}
1897
1898static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
1899                              const char *name)
1900{
1901    QEMUSnapshotInfo *sn_tab, *sn;
1902    int nb_sns, i, ret;
1903
1904    ret = -ENOENT;
1905    nb_sns = bdrv_snapshot_list(bs, &sn_tab);
1906    if (nb_sns < 0)
1907        return ret;
1908    for(i = 0; i < nb_sns; i++) {
1909        sn = &sn_tab[i];
1910        if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
1911            *sn_info = *sn;
1912            ret = 0;
1913            break;
1914        }
1915    }
1916    g_free(sn_tab);
1917    return ret;
1918}
1919
1920/*
1921 * Deletes snapshots of a given name in all opened images.
1922 */
1923static int del_existing_snapshots(Monitor *mon, const char *name)
1924{
1925    BlockDriverState *bs;
1926    QEMUSnapshotInfo sn1, *snapshot = &sn1;
1927    int ret;
1928
1929    bs = NULL;
1930    while ((bs = bdrv_next(bs))) {
1931        if (bdrv_can_snapshot(bs) &&
1932            bdrv_snapshot_find(bs, snapshot, name) >= 0)
1933        {
1934            ret = bdrv_snapshot_delete(bs, name);
1935            if (ret < 0) {
1936                monitor_printf(mon,
1937                               "Error while deleting snapshot on '%s'\n",
1938                               bdrv_get_device_name(bs));
1939                return -1;
1940            }
1941        }
1942    }
1943
1944    return 0;
1945}
1946
1947void do_savevm(Monitor *mon, const QDict *qdict)
1948{
1949    BlockDriverState *bs, *bs1;
1950    QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
1951    int ret;
1952    QEMUFile *f;
1953    int saved_vm_running;
1954    uint32_t vm_state_size;
1955#ifdef _WIN32
1956    struct _timeb tb;
1957    struct tm *ptm;
1958#else
1959    struct timeval tv;
1960    struct tm tm;
1961#endif
1962    const char *name = qdict_get_try_str(qdict, "name");
1963
1964    /* Verify if there is a device that doesn't support snapshots and is writable */
1965    bs = NULL;
1966    while ((bs = bdrv_next(bs))) {
1967
1968        if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
1969            continue;
1970        }
1971
1972        if (!bdrv_can_snapshot(bs)) {
1973            monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
1974                               bdrv_get_device_name(bs));
1975            return;
1976        }
1977    }
1978
1979    bs = bdrv_snapshots();
1980    if (!bs) {
1981        monitor_printf(mon, "No block device can accept snapshots\n");
1982        return;
1983    }
1984
1985    saved_vm_running = runstate_is_running();
1986    vm_stop(RUN_STATE_SAVE_VM);
1987
1988    memset(sn, 0, sizeof(*sn));
1989
1990    /* fill auxiliary fields */
1991#ifdef _WIN32
1992    _ftime(&tb);
1993    sn->date_sec = tb.time;
1994    sn->date_nsec = tb.millitm * 1000000;
1995#else
1996    gettimeofday(&tv, NULL);
1997    sn->date_sec = tv.tv_sec;
1998    sn->date_nsec = tv.tv_usec * 1000;
1999#endif
2000    sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
2001
2002    if (name) {
2003        ret = bdrv_snapshot_find(bs, old_sn, name);
2004        if (ret >= 0) {
2005            pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
2006            pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
2007        } else {
2008            pstrcpy(sn->name, sizeof(sn->name), name);
2009        }
2010    } else {
2011#ifdef _WIN32
2012        ptm = localtime(&tb.time);
2013        strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", ptm);
2014#else
2015        /* cast below needed for OpenBSD where tv_sec is still 'long' */
2016        localtime_r((const time_t *)&tv.tv_sec, &tm);
2017        strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
2018#endif
2019    }
2020
2021    /* Delete old snapshots of the same name */
2022    if (name && del_existing_snapshots(mon, name) < 0) {
2023        goto the_end;
2024    }
2025
2026    /* save the VM state */
2027    f = qemu_fopen_bdrv(bs, 1);
2028    if (!f) {
2029        monitor_printf(mon, "Could not open VM state file\n");
2030        goto the_end;
2031    }
2032    ret = qemu_savevm_state(mon, f);
2033    vm_state_size = qemu_ftell(f);
2034    qemu_fclose(f);
2035    if (ret < 0) {
2036        monitor_printf(mon, "Error %d while writing VM\n", ret);
2037        goto the_end;
2038    }
2039
2040    /* create the snapshots */
2041
2042    bs1 = NULL;
2043    while ((bs1 = bdrv_next(bs1))) {
2044        if (bdrv_can_snapshot(bs1)) {
2045            /* Write VM state size only to the image that contains the state */
2046            sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
2047            ret = bdrv_snapshot_create(bs1, sn);
2048            if (ret < 0) {
2049                monitor_printf(mon, "Error while creating snapshot on '%s'\n",
2050                               bdrv_get_device_name(bs1));
2051            }
2052        }
2053    }
2054
2055 the_end:
2056    if (saved_vm_running)
2057        vm_start();
2058}
2059
2060int load_vmstate(const char *name)
2061{
2062    BlockDriverState *bs, *bs_vm_state;
2063    QEMUSnapshotInfo sn;
2064    QEMUFile *f;
2065    int ret;
2066
2067    bs_vm_state = bdrv_snapshots();
2068    if (!bs_vm_state) {
2069        error_report("No block device supports snapshots");
2070        return -ENOTSUP;
2071    }
2072
2073    /* Don't even try to load empty VM states */
2074    ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
2075    if (ret < 0) {
2076        return ret;
2077    } else if (sn.vm_state_size == 0) {
2078        error_report("This is a disk-only snapshot. Revert to it offline "
2079            "using qemu-img.");
2080        return -EINVAL;
2081    }
2082
2083    /* Verify if there is any device that doesn't support snapshots and is
2084    writable and check if the requested snapshot is available too. */
2085    bs = NULL;
2086    while ((bs = bdrv_next(bs))) {
2087
2088        if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2089            continue;
2090        }
2091
2092        if (!bdrv_can_snapshot(bs)) {
2093            error_report("Device '%s' is writable but does not support snapshots.",
2094                               bdrv_get_device_name(bs));
2095            return -ENOTSUP;
2096        }
2097
2098        ret = bdrv_snapshot_find(bs, &sn, name);
2099        if (ret < 0) {
2100            error_report("Device '%s' does not have the requested snapshot '%s'",
2101                           bdrv_get_device_name(bs), name);
2102            return ret;
2103        }
2104    }
2105
2106    /* Flush all IO requests so they don't interfere with the new state.  */
2107    qemu_aio_flush();
2108
2109    bs = NULL;
2110    while ((bs = bdrv_next(bs))) {
2111        if (bdrv_can_snapshot(bs)) {
2112            ret = bdrv_snapshot_goto(bs, name);
2113            if (ret < 0) {
2114                error_report("Error %d while activating snapshot '%s' on '%s'",
2115                             ret, name, bdrv_get_device_name(bs));
2116                return ret;
2117            }
2118        }
2119    }
2120
2121    /* restore the VM state */
2122    f = qemu_fopen_bdrv(bs_vm_state, 0);
2123    if (!f) {
2124        error_report("Could not open VM state file");
2125        return -EINVAL;
2126    }
2127
2128    qemu_system_reset(VMRESET_SILENT);
2129    ret = qemu_loadvm_state(f);
2130
2131    qemu_fclose(f);
2132    if (ret < 0) {
2133        error_report("Error %d while loading VM state", ret);
2134        return ret;
2135    }
2136
2137    return 0;
2138}
2139
2140void do_delvm(Monitor *mon, const QDict *qdict)
2141{
2142    BlockDriverState *bs, *bs1;
2143    int ret;
2144    const char *name = qdict_get_str(qdict, "name");
2145
2146    bs = bdrv_snapshots();
2147    if (!bs) {
2148        monitor_printf(mon, "No block device supports snapshots\n");
2149        return;
2150    }
2151
2152    bs1 = NULL;
2153    while ((bs1 = bdrv_next(bs1))) {
2154        if (bdrv_can_snapshot(bs1)) {
2155            ret = bdrv_snapshot_delete(bs1, name);
2156            if (ret < 0) {
2157                if (ret == -ENOTSUP)
2158                    monitor_printf(mon,
2159                                   "Snapshots not supported on device '%s'\n",
2160                                   bdrv_get_device_name(bs1));
2161                else
2162                    monitor_printf(mon, "Error %d while deleting snapshot on "
2163                                   "'%s'\n", ret, bdrv_get_device_name(bs1));
2164            }
2165        }
2166    }
2167}
2168
2169void do_info_snapshots(Monitor *mon)
2170{
2171    BlockDriverState *bs, *bs1;
2172    QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
2173    int nb_sns, i, ret, available;
2174    int total;
2175    int *available_snapshots;
2176    char buf[256];
2177
2178    bs = bdrv_snapshots();
2179    if (!bs) {
2180        monitor_printf(mon, "No available block device supports snapshots\n");
2181        return;
2182    }
2183
2184    nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2185    if (nb_sns < 0) {
2186        monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
2187        return;
2188    }
2189
2190    if (nb_sns == 0) {
2191        monitor_printf(mon, "There is no snapshot available.\n");
2192        return;
2193    }
2194
2195    available_snapshots = g_malloc0(sizeof(int) * nb_sns);
2196    total = 0;
2197    for (i = 0; i < nb_sns; i++) {
2198        sn = &sn_tab[i];
2199        available = 1;
2200        bs1 = NULL;
2201
2202        while ((bs1 = bdrv_next(bs1))) {
2203            if (bdrv_can_snapshot(bs1) && bs1 != bs) {
2204                ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
2205                if (ret < 0) {
2206                    available = 0;
2207                    break;
2208                }
2209            }
2210        }
2211
2212        if (available) {
2213            available_snapshots[total] = i;
2214            total++;
2215        }
2216    }
2217
2218    if (total > 0) {
2219        monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
2220        for (i = 0; i < total; i++) {
2221            sn = &sn_tab[available_snapshots[i]];
2222            monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
2223        }
2224    } else {
2225        monitor_printf(mon, "There is no suitable snapshot available\n");
2226    }
2227
2228    g_free(sn_tab);
2229    g_free(available_snapshots);
2230
2231}
2232