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 "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
  96 static 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
 121 static 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
 132 static 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
 149 void 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
 161 struct 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
 180 typedef struct QEMUFileStdio
 181 {
 182     FILE *stdio_file;
 183     QEMUFile *file;
 184 } QEMUFileStdio;
 185
 186 typedef struct QEMUFileSocket
 187 {
 188     int fd;
 189     QEMUFile *file;
 190 } QEMUFileSocket;
 191
 192 static 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
 207 static int socket_close(void *opaque)
 208 {
 209     QEMUFileSocket *s = opaque;
 210     g_free(s);
 211     return 0;
 212 }
 213
 214 static 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
 220 static 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
 233 static 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
 242 static int stdio_fclose(void *opaque)
 243 {
 244     QEMUFileStdio *s = opaque;
 245     fclose(s->stdio_file);
 246     g_free(s);
 247     return 0;
 248 }
 249
 250 QEMUFile *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
 273 QEMUFile *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
 285 int 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
 296 QEMUFile *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
 321 fail:
 322     g_free(s);
 323     return NULL;
 324 }
 325
 326 QEMUFile *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
 336 static 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
 344 static 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
 351 QEMUFile *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;
 376 fail:
 377     g_free(s);
 378     return NULL;
 379 }
 380
 381 static 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
 388 static 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
 393 static int bdrv_fclose(void *opaque)
 394 {
 395     return 0;
 396 }
 397
 398 static 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
 406 QEMUFile *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
 429 int qemu_file_get_error(QEMUFile *f)
 430 {
 431     return f->last_error;
 432 }
 433
 434 void qemu_file_set_error(QEMUFile *f, int ret)
 435 {
 436     f->last_error = ret;
 437 }
 438
 439 void 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
 456 static 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
 485 int 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
 495 void qemu_file_put_notify(QEMUFile *f)
 496 {
 497     f->put_buffer(f->opaque, NULL, 0, 0);
 498 }
 499
 500 void 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
 524 void 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
 538 static 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
 545 static 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
 573 int 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
 593 static 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
 611 int 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
 620 int64_t qemu_ftell(QEMUFile *f)
 621 {
 622     return f->buf_offset - f->buf_size + f->buf_index;
 623 }
 624
 625 int64_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
 646 int 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
 654 int64_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
 662 int64_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
 672 void qemu_put_be16(QEMUFile *f, unsigned int v)
 673 {
 674     qemu_put_byte(f, v >> 8);
 675     qemu_put_byte(f, v);
 676 }
 677
 678 void 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
 686 void qemu_put_be64(QEMUFile *f, uint64_t v)
 687 {
 688     qemu_put_be32(f, v >> 32);
 689     qemu_put_be32(f, v);
 690 }
 691
 692 unsigned 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
 700 unsigned 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
 710 uint64_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
 721 void 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
 729 void 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
 744 static 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
 751 static void put_bool(QEMUFile *f, void *pv, size_t size)
 752 {
 753     bool *v = pv;
 754     qemu_put_byte(f, *v);
 755 }
 756
 757 const VMStateInfo vmstate_info_bool = {
 758     .name = "bool",
 759     .get  = get_bool,
 760     .put  = put_bool,
 761 };
 762
 763 /* 8 bit int */
 764
 765 static 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
 772 static void put_int8(QEMUFile *f, void *pv, size_t size)
 773 {
 774     int8_t *v = pv;
 775     qemu_put_s8s(f, v);
 776 }
 777
 778 const VMStateInfo vmstate_info_int8 = {
 779     .name = "int8",
 780     .get  = get_int8,
 781     .put  = put_int8,
 782 };
 783
 784 /* 16 bit int */
 785
 786 static 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
 793 static void put_int16(QEMUFile *f, void *pv, size_t size)
 794 {
 795     int16_t *v = pv;
 796     qemu_put_sbe16s(f, v);
 797 }
 798
 799 const VMStateInfo vmstate_info_int16 = {
 800     .name = "int16",
 801     .get  = get_int16,
 802     .put  = put_int16,
 803 };
 804
 805 /* 32 bit int */
 806
 807 static 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
 814 static void put_int32(QEMUFile *f, void *pv, size_t size)
 815 {
 816     int32_t *v = pv;
 817     qemu_put_sbe32s(f, v);
 818 }
 819
 820 const 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
 829 static 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
 840 const 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
 849 static 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
 860 const 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
 868 static 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
 875 static void put_int64(QEMUFile *f, void *pv, size_t size)
 876 {
 877     int64_t *v = pv;
 878     qemu_put_sbe64s(f, v);
 879 }
 880
 881 const VMStateInfo vmstate_info_int64 = {
 882     .name = "int64",
 883     .get  = get_int64,
 884     .put  = put_int64,
 885 };
 886
 887 /* 8 bit unsigned int */
 888
 889 static 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
 896 static void put_uint8(QEMUFile *f, void *pv, size_t size)
 897 {
 898     uint8_t *v = pv;
 899     qemu_put_8s(f, v);
 900 }
 901
 902 const VMStateInfo vmstate_info_uint8 = {
 903     .name = "uint8",
 904     .get  = get_uint8,
 905     .put  = put_uint8,
 906 };
 907
 908 /* 16 bit unsigned int */
 909
 910 static 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
 917 static void put_uint16(QEMUFile *f, void *pv, size_t size)
 918 {
 919     uint16_t *v = pv;
 920     qemu_put_be16s(f, v);
 921 }
 922
 923 const VMStateInfo vmstate_info_uint16 = {
 924     .name = "uint16",
 925     .get  = get_uint16,
 926     .put  = put_uint16,
 927 };
 928
 929 /* 32 bit unsigned int */
 930
 931 static 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
 938 static void put_uint32(QEMUFile *f, void *pv, size_t size)
 939 {
 940     uint32_t *v = pv;
 941     qemu_put_be32s(f, v);
 942 }
 943
 944 const 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
 953 static 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
 965 const 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
 973 static 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
 980 static void put_uint64(QEMUFile *f, void *pv, size_t size)
 981 {
 982     uint64_t *v = pv;
 983     qemu_put_be64s(f, v);
 984 }
 985
 986 const 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
 995 static 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
1006 const 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
1015 static 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
1026 const VMStateInfo vmstate_info_uint16_equal = {
1027     .name = "uint16 equal",
1028     .get  = get_uint16_equal,
1029     .put  = put_uint16,
1030 };
1031
1032 /* timers  */
1033
1034 static 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
1041 static void put_timer(QEMUFile *f, void *pv, size_t size)
1042 {
1043     QEMUTimer *v = pv;
1044     qemu_put_timer(f, v);
1045 }
1046
1047 const VMStateInfo vmstate_info_timer = {
1048     .name = "timer",
1049     .get  = get_timer,
1050     .put  = put_timer,
1051 };
1052
1053 /* uint8_t buffers */
1054
1055 static 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
1062 static 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
1068 const 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
1077 static 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
1090 static 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
1102 const VMStateInfo vmstate_info_unused_buffer = {
1103     .name = "unused_buffer",
1104     .get  = get_unused_buffer,
1105     .put  = put_unused_buffer,
1106 };
1107
1108 typedef struct CompatEntry {
1109     char idstr[256];
1110     int instance_id;
1111 } CompatEntry;
1112
1113 typedef 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
1131 static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
1132     QTAILQ_HEAD_INITIALIZER(savevm_handlers);
1133 static int global_section_id;
1134
1135 static 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
1149 static 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. */
1170 int 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
1220 int 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
1232 void 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
1258 int 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
1306 int 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
1313 void 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
1329 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1330                                     void *opaque);
1331 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1332                                    void *opaque);
1333
1334 int 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
1412 void 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
1463 static 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
1471 static 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
1491 bool 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
1505 int 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 function 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  */
1560 int 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
1592 int 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
1639 void 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
1650 static 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
1671 out:
1672     if (ret == 0) {
1673         ret = qemu_file_get_error(f);
1674     }
1675
1676     return ret;
1677 }
1678
1679 static 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
1699 static 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
1710 static 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
1751 static 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
1772 typedef struct LoadStateEntry {
1773     QLIST_ENTRY(LoadStateEntry) entry;
1774     SaveStateEntry *se;
1775     int section_id;
1776     int version_id;
1777 } LoadStateEntry;
1778
1779 int 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
1885 out:
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
1898 static 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  */
1923 static 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
1947 void 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
2060 int 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     bdrv_drain_all();
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
2140 void 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
2169 void 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 }