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 #include "memory.h"
  87 #include "qmp-commands.h"
  88
  89 #define SELF_ANNOUNCE_ROUNDS 5
  90
  91 #ifndef ETH_P_RARP
  92 #define ETH_P_RARP 0x8035
  93 #endif
  94 #define ARP_HTYPE_ETH 0x0001
  95 #define ARP_PTYPE_IP 0x0800
  96 #define ARP_OP_REQUEST_REV 0x3
  97
  98 static int announce_self_create(uint8_t *buf,
  99                                 uint8_t *mac_addr)
 100 {
 101     /* Ethernet header. */
 102     memset(buf, 0xff, 6);         /* destination MAC addr */
 103     memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
 104     *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */
 105
 106     /* RARP header. */
 107     *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
 108     *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
 109     *(buf + 18) = 6; /* hardware addr length (ethernet) */
 110     *(buf + 19) = 4; /* protocol addr length (IPv4) */
 111     *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
 112     memcpy(buf + 22, mac_addr, 6); /* source hw addr */
 113     memset(buf + 28, 0x00, 4);     /* source protocol addr */
 114     memcpy(buf + 32, mac_addr, 6); /* target hw addr */
 115     memset(buf + 38, 0x00, 4);     /* target protocol addr */
 116
 117     /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
 118     memset(buf + 42, 0x00, 18);
 119
 120     return 60; /* len (FCS will be added by hardware) */
 121 }
 122
 123 static void qemu_announce_self_iter(NICState *nic, void *opaque)
 124 {
 125     uint8_t buf[60];
 126     int len;
 127
 128     len = announce_self_create(buf, nic->conf->macaddr.a);
 129
 130     qemu_send_packet_raw(&nic->nc, buf, len);
 131 }
 132
 133
 134 static void qemu_announce_self_once(void *opaque)
 135 {
 136     static int count = SELF_ANNOUNCE_ROUNDS;
 137     QEMUTimer *timer = *(QEMUTimer **)opaque;
 138
 139     qemu_foreach_nic(qemu_announce_self_iter, NULL);
 140
 141     if (--count) {
 142         /* delay 50ms, 150ms, 250ms, ... */
 143         qemu_mod_timer(timer, qemu_get_clock_ms(rt_clock) +
 144                        50 + (SELF_ANNOUNCE_ROUNDS - count - 1) * 100);
 145     } else {
 146             qemu_del_timer(timer);
 147             qemu_free_timer(timer);
 148     }
 149 }
 150
 151 void qemu_announce_self(void)
 152 {
 153         static QEMUTimer *timer;
 154         timer = qemu_new_timer_ms(rt_clock, qemu_announce_self_once, &timer);
 155         qemu_announce_self_once(&timer);
 156 }
 157
 158 /***********************************************************/
 159 /* savevm/loadvm support */
 160
 161 #define IO_BUF_SIZE 32768
 162
 163 struct QEMUFile {
 164     QEMUFilePutBufferFunc *put_buffer;
 165     QEMUFileGetBufferFunc *get_buffer;
 166     QEMUFileCloseFunc *close;
 167     QEMUFileRateLimit *rate_limit;
 168     QEMUFileSetRateLimit *set_rate_limit;
 169     QEMUFileGetRateLimit *get_rate_limit;
 170     void *opaque;
 171     int is_write;
 172
 173     int64_t buf_offset; /* start of buffer when writing, end of buffer
 174                            when reading */
 175     int buf_index;
 176     int buf_size; /* 0 when writing */
 177     uint8_t buf[IO_BUF_SIZE];
 178
 179     int last_error;
 180 };
 181
 182 typedef struct QEMUFileStdio
 183 {
 184     FILE *stdio_file;
 185     QEMUFile *file;
 186 } QEMUFileStdio;
 187
 188 typedef struct QEMUFileSocket
 189 {
 190     int fd;
 191     QEMUFile *file;
 192 } QEMUFileSocket;
 193
 194 static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 195 {
 196     QEMUFileSocket *s = opaque;
 197     ssize_t len;
 198
 199     do {
 200         len = qemu_recv(s->fd, buf, size, 0);
 201     } while (len == -1 && socket_error() == EINTR);
 202
 203     if (len == -1)
 204         len = -socket_error();
 205
 206     return len;
 207 }
 208
 209 static int socket_close(void *opaque)
 210 {
 211     QEMUFileSocket *s = opaque;
 212     g_free(s);
 213     return 0;
 214 }
 215
 216 static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
 217 {
 218     QEMUFileStdio *s = opaque;
 219     return fwrite(buf, 1, size, s->stdio_file);
 220 }
 221
 222 static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 223 {
 224     QEMUFileStdio *s = opaque;
 225     FILE *fp = s->stdio_file;
 226     int bytes;
 227
 228     do {
 229         clearerr(fp);
 230         bytes = fread(buf, 1, size, fp);
 231     } while ((bytes == 0) && ferror(fp) && (errno == EINTR));
 232     return bytes;
 233 }
 234
 235 static int stdio_pclose(void *opaque)
 236 {
 237     QEMUFileStdio *s = opaque;
 238     int ret;
 239     ret = pclose(s->stdio_file);
 240     if (ret == -1) {
 241         ret = -errno;
 242     }
 243     g_free(s);
 244     return ret;
 245 }
 246
 247 static int stdio_fclose(void *opaque)
 248 {
 249     QEMUFileStdio *s = opaque;
 250     int ret = 0;
 251     if (fclose(s->stdio_file) == EOF) {
 252         ret = -errno;
 253     }
 254     g_free(s);
 255     return ret;
 256 }
 257
 258 QEMUFile *qemu_popen(FILE *stdio_file, const char *mode)
 259 {
 260     QEMUFileStdio *s;
 261
 262     if (stdio_file == NULL || mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) {
 263         fprintf(stderr, "qemu_popen: Argument validity check failed\n");
 264         return NULL;
 265     }
 266
 267     s = g_malloc0(sizeof(QEMUFileStdio));
 268
 269     s->stdio_file = stdio_file;
 270
 271     if(mode[0] == 'r') {
 272         s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_pclose,
 273                                  NULL, NULL, NULL);
 274     } else {
 275         s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_pclose,
 276                                  NULL, NULL, NULL);
 277     }
 278     return s->file;
 279 }
 280
 281 QEMUFile *qemu_popen_cmd(const char *command, const char *mode)
 282 {
 283     FILE *popen_file;
 284
 285     popen_file = popen(command, mode);
 286     if(popen_file == NULL) {
 287         return NULL;
 288     }
 289
 290     return qemu_popen(popen_file, mode);
 291 }
 292
 293 int qemu_stdio_fd(QEMUFile *f)
 294 {
 295     QEMUFileStdio *p;
 296     int fd;
 297
 298     p = (QEMUFileStdio *)f->opaque;
 299     fd = fileno(p->stdio_file);
 300
 301     return fd;
 302 }
 303
 304 QEMUFile *qemu_fdopen(int fd, const char *mode)
 305 {
 306     QEMUFileStdio *s;
 307
 308     if (mode == NULL ||
 309         (mode[0] != 'r' && mode[0] != 'w') ||
 310         mode[1] != 'b' || mode[2] != 0) {
 311         fprintf(stderr, "qemu_fdopen: Argument validity check failed\n");
 312         return NULL;
 313     }
 314
 315     s = g_malloc0(sizeof(QEMUFileStdio));
 316     s->stdio_file = fdopen(fd, mode);
 317     if (!s->stdio_file)
 318         goto fail;
 319
 320     if(mode[0] == 'r') {
 321         s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_fclose,
 322                                  NULL, NULL, NULL);
 323     } else {
 324         s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_fclose,
 325                                  NULL, NULL, NULL);
 326     }
 327     return s->file;
 328
 329 fail:
 330     g_free(s);
 331     return NULL;
 332 }
 333
 334 QEMUFile *qemu_fopen_socket(int fd)
 335 {
 336     QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
 337
 338     s->fd = fd;
 339     s->file = qemu_fopen_ops(s, NULL, socket_get_buffer, socket_close,
 340                              NULL, NULL, NULL);
 341     return s->file;
 342 }
 343
 344 static int file_put_buffer(void *opaque, const uint8_t *buf,
 345                             int64_t pos, int size)
 346 {
 347     QEMUFileStdio *s = opaque;
 348     fseek(s->stdio_file, pos, SEEK_SET);
 349     return fwrite(buf, 1, size, s->stdio_file);
 350 }
 351
 352 static int file_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 353 {
 354     QEMUFileStdio *s = opaque;
 355     fseek(s->stdio_file, pos, SEEK_SET);
 356     return fread(buf, 1, size, s->stdio_file);
 357 }
 358
 359 QEMUFile *qemu_fopen(const char *filename, const char *mode)
 360 {
 361     QEMUFileStdio *s;
 362
 363     if (mode == NULL ||
 364         (mode[0] != 'r' && mode[0] != 'w') ||
 365         mode[1] != 'b' || mode[2] != 0) {
 366         fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
 367         return NULL;
 368     }
 369
 370     s = g_malloc0(sizeof(QEMUFileStdio));
 371
 372     s->stdio_file = fopen(filename, mode);
 373     if (!s->stdio_file)
 374         goto fail;
 375
 376     if(mode[0] == 'w') {
 377         s->file = qemu_fopen_ops(s, file_put_buffer, NULL, stdio_fclose,
 378                                  NULL, NULL, NULL);
 379     } else {
 380         s->file = qemu_fopen_ops(s, NULL, file_get_buffer, stdio_fclose,
 381                                NULL, NULL, NULL);
 382     }
 383     return s->file;
 384 fail:
 385     g_free(s);
 386     return NULL;
 387 }
 388
 389 static int block_put_buffer(void *opaque, const uint8_t *buf,
 390                            int64_t pos, int size)
 391 {
 392     bdrv_save_vmstate(opaque, buf, pos, size);
 393     return size;
 394 }
 395
 396 static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 397 {
 398     return bdrv_load_vmstate(opaque, buf, pos, size);
 399 }
 400
 401 static int bdrv_fclose(void *opaque)
 402 {
 403     return 0;
 404 }
 405
 406 static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
 407 {
 408     if (is_writable)
 409         return qemu_fopen_ops(bs, block_put_buffer, NULL, bdrv_fclose,
 410                               NULL, NULL, NULL);
 411     return qemu_fopen_ops(bs, NULL, block_get_buffer, bdrv_fclose, NULL, NULL, NULL);
 412 }
 413
 414 QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer,
 415                          QEMUFileGetBufferFunc *get_buffer,
 416                          QEMUFileCloseFunc *close,
 417                          QEMUFileRateLimit *rate_limit,
 418                          QEMUFileSetRateLimit *set_rate_limit,
 419                          QEMUFileGetRateLimit *get_rate_limit)
 420 {
 421     QEMUFile *f;
 422
 423     f = g_malloc0(sizeof(QEMUFile));
 424
 425     f->opaque = opaque;
 426     f->put_buffer = put_buffer;
 427     f->get_buffer = get_buffer;
 428     f->close = close;
 429     f->rate_limit = rate_limit;
 430     f->set_rate_limit = set_rate_limit;
 431     f->get_rate_limit = get_rate_limit;
 432     f->is_write = 0;
 433
 434     return f;
 435 }
 436
 437 int qemu_file_get_error(QEMUFile *f)
 438 {
 439     return f->last_error;
 440 }
 441
 442 void qemu_file_set_error(QEMUFile *f, int ret)
 443 {
 444     f->last_error = ret;
 445 }
 446
 447 /** Sets last_error conditionally
 448  *
 449  * Sets last_error only if ret is negative _and_ no error
 450  * was set before.
 451  */
 452 static void qemu_file_set_if_error(QEMUFile *f, int ret)
 453 {
 454     if (ret < 0 && !f->last_error) {
 455         qemu_file_set_error(f, ret);
 456     }
 457 }
 458
 459 /** Flushes QEMUFile buffer
 460  *
 461  * In case of error, last_error is set.
 462  */
 463 void qemu_fflush(QEMUFile *f)
 464 {
 465     if (!f->put_buffer)
 466         return;
 467
 468     if (f->is_write && f->buf_index > 0) {
 469         int len;
 470
 471         len = f->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index);
 472         if (len > 0)
 473             f->buf_offset += f->buf_index;
 474         else
 475             qemu_file_set_error(f, -EINVAL);
 476         f->buf_index = 0;
 477     }
 478 }
 479
 480 static void qemu_fill_buffer(QEMUFile *f)
 481 {
 482     int len;
 483     int pending;
 484
 485     if (!f->get_buffer)
 486         return;
 487
 488     if (f->is_write)
 489         abort();
 490
 491     pending = f->buf_size - f->buf_index;
 492     if (pending > 0) {
 493         memmove(f->buf, f->buf + f->buf_index, pending);
 494     }
 495     f->buf_index = 0;
 496     f->buf_size = pending;
 497
 498     len = f->get_buffer(f->opaque, f->buf + pending, f->buf_offset,
 499                         IO_BUF_SIZE - pending);
 500     if (len > 0) {
 501         f->buf_size += len;
 502         f->buf_offset += len;
 503     } else if (len == 0) {
 504         f->last_error = -EIO;
 505     } else if (len != -EAGAIN)
 506         qemu_file_set_error(f, len);
 507 }
 508
 509 /** Calls close function and set last_error if needed
 510  *
 511  * Internal function. qemu_fflush() must be called before this.
 512  *
 513  * Returns f->close() return value, or 0 if close function is not set.
 514  */
 515 static int qemu_close(QEMUFile *f)
 516 {
 517     int ret = 0;
 518     if (f->close) {
 519         ret = f->close(f->opaque);
 520         qemu_file_set_if_error(f, ret);
 521     }
 522     return ret;
 523 }
 524
 525 /** Closes the file
 526  *
 527  * Returns negative error value if any error happened on previous operations or
 528  * while closing the file. Returns 0 or positive number on success.
 529  *
 530  * The meaning of return value on success depends on the specific backend
 531  * being used.
 532  */
 533 int qemu_fclose(QEMUFile *f)
 534 {
 535     int ret;
 536     qemu_fflush(f);
 537     ret = qemu_close(f);
 538     /* If any error was spotted before closing, we should report it
 539      * instead of the close() return value.
 540      */
 541     if (f->last_error) {
 542         ret = f->last_error;
 543     }
 544     g_free(f);
 545     return ret;
 546 }
 547
 548 void qemu_file_put_notify(QEMUFile *f)
 549 {
 550     f->put_buffer(f->opaque, NULL, 0, 0);
 551 }
 552
 553 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
 554 {
 555     int l;
 556
 557     if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
 558         fprintf(stderr,
 559                 "Attempted to write to buffer while read buffer is not empty\n");
 560         abort();
 561     }
 562
 563     while (!f->last_error && size > 0) {
 564         l = IO_BUF_SIZE - f->buf_index;
 565         if (l > size)
 566             l = size;
 567         memcpy(f->buf + f->buf_index, buf, l);
 568         f->is_write = 1;
 569         f->buf_index += l;
 570         buf += l;
 571         size -= l;
 572         if (f->buf_index >= IO_BUF_SIZE)
 573             qemu_fflush(f);
 574     }
 575 }
 576
 577 void qemu_put_byte(QEMUFile *f, int v)
 578 {
 579     if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
 580         fprintf(stderr,
 581                 "Attempted to write to buffer while read buffer is not empty\n");
 582         abort();
 583     }
 584
 585     f->buf[f->buf_index++] = v;
 586     f->is_write = 1;
 587     if (f->buf_index >= IO_BUF_SIZE)
 588         qemu_fflush(f);
 589 }
 590
 591 static void qemu_file_skip(QEMUFile *f, int size)
 592 {
 593     if (f->buf_index + size <= f->buf_size) {
 594         f->buf_index += size;
 595     }
 596 }
 597
 598 static int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset)
 599 {
 600     int pending;
 601     int index;
 602
 603     if (f->is_write) {
 604         abort();
 605     }
 606
 607     index = f->buf_index + offset;
 608     pending = f->buf_size - index;
 609     if (pending < size) {
 610         qemu_fill_buffer(f);
 611         index = f->buf_index + offset;
 612         pending = f->buf_size - index;
 613     }
 614
 615     if (pending <= 0) {
 616         return 0;
 617     }
 618     if (size > pending) {
 619         size = pending;
 620     }
 621
 622     memcpy(buf, f->buf + index, size);
 623     return size;
 624 }
 625
 626 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size)
 627 {
 628     int pending = size;
 629     int done = 0;
 630
 631     while (pending > 0) {
 632         int res;
 633
 634         res = qemu_peek_buffer(f, buf, pending, 0);
 635         if (res == 0) {
 636             return done;
 637         }
 638         qemu_file_skip(f, res);
 639         buf += res;
 640         pending -= res;
 641         done += res;
 642     }
 643     return done;
 644 }
 645
 646 static int qemu_peek_byte(QEMUFile *f, int offset)
 647 {
 648     int index = f->buf_index + offset;
 649
 650     if (f->is_write) {
 651         abort();
 652     }
 653
 654     if (index >= f->buf_size) {
 655         qemu_fill_buffer(f);
 656         index = f->buf_index + offset;
 657         if (index >= f->buf_size) {
 658             return 0;
 659         }
 660     }
 661     return f->buf[index];
 662 }
 663
 664 int qemu_get_byte(QEMUFile *f)
 665 {
 666     int result;
 667
 668     result = qemu_peek_byte(f, 0);
 669     qemu_file_skip(f, 1);
 670     return result;
 671 }
 672
 673 int64_t qemu_ftell(QEMUFile *f)
 674 {
 675     return f->buf_offset - f->buf_size + f->buf_index;
 676 }
 677
 678 int64_t qemu_fseek(QEMUFile *f, int64_t pos, int whence)
 679 {
 680     if (whence == SEEK_SET) {
 681         /* nothing to do */
 682     } else if (whence == SEEK_CUR) {
 683         pos += qemu_ftell(f);
 684     } else {
 685         /* SEEK_END not supported */
 686         return -1;
 687     }
 688     if (f->put_buffer) {
 689         qemu_fflush(f);
 690         f->buf_offset = pos;
 691     } else {
 692         f->buf_offset = pos;
 693         f->buf_index = 0;
 694         f->buf_size = 0;
 695     }
 696     return pos;
 697 }
 698
 699 int qemu_file_rate_limit(QEMUFile *f)
 700 {
 701     if (f->rate_limit)
 702         return f->rate_limit(f->opaque);
 703
 704     return 0;
 705 }
 706
 707 int64_t qemu_file_get_rate_limit(QEMUFile *f)
 708 {
 709     if (f->get_rate_limit)
 710         return f->get_rate_limit(f->opaque);
 711
 712     return 0;
 713 }
 714
 715 int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate)
 716 {
 717     /* any failed or completed migration keeps its state to allow probing of
 718      * migration data, but has no associated file anymore */
 719     if (f && f->set_rate_limit)
 720         return f->set_rate_limit(f->opaque, new_rate);
 721
 722     return 0;
 723 }
 724
 725 void qemu_put_be16(QEMUFile *f, unsigned int v)
 726 {
 727     qemu_put_byte(f, v >> 8);
 728     qemu_put_byte(f, v);
 729 }
 730
 731 void qemu_put_be32(QEMUFile *f, unsigned int v)
 732 {
 733     qemu_put_byte(f, v >> 24);
 734     qemu_put_byte(f, v >> 16);
 735     qemu_put_byte(f, v >> 8);
 736     qemu_put_byte(f, v);
 737 }
 738
 739 void qemu_put_be64(QEMUFile *f, uint64_t v)
 740 {
 741     qemu_put_be32(f, v >> 32);
 742     qemu_put_be32(f, v);
 743 }
 744
 745 unsigned int qemu_get_be16(QEMUFile *f)
 746 {
 747     unsigned int v;
 748     v = qemu_get_byte(f) << 8;
 749     v |= qemu_get_byte(f);
 750     return v;
 751 }
 752
 753 unsigned int qemu_get_be32(QEMUFile *f)
 754 {
 755     unsigned int v;
 756     v = qemu_get_byte(f) << 24;
 757     v |= qemu_get_byte(f) << 16;
 758     v |= qemu_get_byte(f) << 8;
 759     v |= qemu_get_byte(f);
 760     return v;
 761 }
 762
 763 uint64_t qemu_get_be64(QEMUFile *f)
 764 {
 765     uint64_t v;
 766     v = (uint64_t)qemu_get_be32(f) << 32;
 767     v |= qemu_get_be32(f);
 768     return v;
 769 }
 770
 771
 772 /* timer */
 773
 774 void qemu_put_timer(QEMUFile *f, QEMUTimer *ts)
 775 {
 776     uint64_t expire_time;
 777
 778     expire_time = qemu_timer_expire_time_ns(ts);
 779     qemu_put_be64(f, expire_time);
 780 }
 781
 782 void qemu_get_timer(QEMUFile *f, QEMUTimer *ts)
 783 {
 784     uint64_t expire_time;
 785
 786     expire_time = qemu_get_be64(f);
 787     if (expire_time != -1) {
 788         qemu_mod_timer_ns(ts, expire_time);
 789     } else {
 790         qemu_del_timer(ts);
 791     }
 792 }
 793
 794
 795 /* bool */
 796
 797 static int get_bool(QEMUFile *f, void *pv, size_t size)
 798 {
 799     bool *v = pv;
 800     *v = qemu_get_byte(f);
 801     return 0;
 802 }
 803
 804 static void put_bool(QEMUFile *f, void *pv, size_t size)
 805 {
 806     bool *v = pv;
 807     qemu_put_byte(f, *v);
 808 }
 809
 810 const VMStateInfo vmstate_info_bool = {
 811     .name = "bool",
 812     .get  = get_bool,
 813     .put  = put_bool,
 814 };
 815
 816 /* 8 bit int */
 817
 818 static int get_int8(QEMUFile *f, void *pv, size_t size)
 819 {
 820     int8_t *v = pv;
 821     qemu_get_s8s(f, v);
 822     return 0;
 823 }
 824
 825 static void put_int8(QEMUFile *f, void *pv, size_t size)
 826 {
 827     int8_t *v = pv;
 828     qemu_put_s8s(f, v);
 829 }
 830
 831 const VMStateInfo vmstate_info_int8 = {
 832     .name = "int8",
 833     .get  = get_int8,
 834     .put  = put_int8,
 835 };
 836
 837 /* 16 bit int */
 838
 839 static int get_int16(QEMUFile *f, void *pv, size_t size)
 840 {
 841     int16_t *v = pv;
 842     qemu_get_sbe16s(f, v);
 843     return 0;
 844 }
 845
 846 static void put_int16(QEMUFile *f, void *pv, size_t size)
 847 {
 848     int16_t *v = pv;
 849     qemu_put_sbe16s(f, v);
 850 }
 851
 852 const VMStateInfo vmstate_info_int16 = {
 853     .name = "int16",
 854     .get  = get_int16,
 855     .put  = put_int16,
 856 };
 857
 858 /* 32 bit int */
 859
 860 static int get_int32(QEMUFile *f, void *pv, size_t size)
 861 {
 862     int32_t *v = pv;
 863     qemu_get_sbe32s(f, v);
 864     return 0;
 865 }
 866
 867 static void put_int32(QEMUFile *f, void *pv, size_t size)
 868 {
 869     int32_t *v = pv;
 870     qemu_put_sbe32s(f, v);
 871 }
 872
 873 const VMStateInfo vmstate_info_int32 = {
 874     .name = "int32",
 875     .get  = get_int32,
 876     .put  = put_int32,
 877 };
 878
 879 /* 32 bit int. See that the received value is the same than the one
 880    in the field */
 881
 882 static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
 883 {
 884     int32_t *v = pv;
 885     int32_t v2;
 886     qemu_get_sbe32s(f, &v2);
 887
 888     if (*v == v2)
 889         return 0;
 890     return -EINVAL;
 891 }
 892
 893 const VMStateInfo vmstate_info_int32_equal = {
 894     .name = "int32 equal",
 895     .get  = get_int32_equal,
 896     .put  = put_int32,
 897 };
 898
 899 /* 32 bit int. See that the received value is the less or the same
 900    than the one in the field */
 901
 902 static int get_int32_le(QEMUFile *f, void *pv, size_t size)
 903 {
 904     int32_t *old = pv;
 905     int32_t new;
 906     qemu_get_sbe32s(f, &new);
 907
 908     if (*old <= new)
 909         return 0;
 910     return -EINVAL;
 911 }
 912
 913 const VMStateInfo vmstate_info_int32_le = {
 914     .name = "int32 equal",
 915     .get  = get_int32_le,
 916     .put  = put_int32,
 917 };
 918
 919 /* 64 bit int */
 920
 921 static int get_int64(QEMUFile *f, void *pv, size_t size)
 922 {
 923     int64_t *v = pv;
 924     qemu_get_sbe64s(f, v);
 925     return 0;
 926 }
 927
 928 static void put_int64(QEMUFile *f, void *pv, size_t size)
 929 {
 930     int64_t *v = pv;
 931     qemu_put_sbe64s(f, v);
 932 }
 933
 934 const VMStateInfo vmstate_info_int64 = {
 935     .name = "int64",
 936     .get  = get_int64,
 937     .put  = put_int64,
 938 };
 939
 940 /* 8 bit unsigned int */
 941
 942 static int get_uint8(QEMUFile *f, void *pv, size_t size)
 943 {
 944     uint8_t *v = pv;
 945     qemu_get_8s(f, v);
 946     return 0;
 947 }
 948
 949 static void put_uint8(QEMUFile *f, void *pv, size_t size)
 950 {
 951     uint8_t *v = pv;
 952     qemu_put_8s(f, v);
 953 }
 954
 955 const VMStateInfo vmstate_info_uint8 = {
 956     .name = "uint8",
 957     .get  = get_uint8,
 958     .put  = put_uint8,
 959 };
 960
 961 /* 16 bit unsigned int */
 962
 963 static int get_uint16(QEMUFile *f, void *pv, size_t size)
 964 {
 965     uint16_t *v = pv;
 966     qemu_get_be16s(f, v);
 967     return 0;
 968 }
 969
 970 static void put_uint16(QEMUFile *f, void *pv, size_t size)
 971 {
 972     uint16_t *v = pv;
 973     qemu_put_be16s(f, v);
 974 }
 975
 976 const VMStateInfo vmstate_info_uint16 = {
 977     .name = "uint16",
 978     .get  = get_uint16,
 979     .put  = put_uint16,
 980 };
 981
 982 /* 32 bit unsigned int */
 983
 984 static int get_uint32(QEMUFile *f, void *pv, size_t size)
 985 {
 986     uint32_t *v = pv;
 987     qemu_get_be32s(f, v);
 988     return 0;
 989 }
 990
 991 static void put_uint32(QEMUFile *f, void *pv, size_t size)
 992 {
 993     uint32_t *v = pv;
 994     qemu_put_be32s(f, v);
 995 }
 996
 997 const VMStateInfo vmstate_info_uint32 = {
 998     .name = "uint32",
 999     .get  = get_uint32,
1000     .put  = put_uint32,
1001 };
1002
1003 /* 32 bit uint. See that the received value is the same than the one
1004    in the field */
1005
1006 static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
1007 {
1008     uint32_t *v = pv;
1009     uint32_t v2;
1010     qemu_get_be32s(f, &v2);
1011
1012     if (*v == v2) {
1013         return 0;
1014     }
1015     return -EINVAL;
1016 }
1017
1018 const VMStateInfo vmstate_info_uint32_equal = {
1019     .name = "uint32 equal",
1020     .get  = get_uint32_equal,
1021     .put  = put_uint32,
1022 };
1023
1024 /* 64 bit unsigned int */
1025
1026 static int get_uint64(QEMUFile *f, void *pv, size_t size)
1027 {
1028     uint64_t *v = pv;
1029     qemu_get_be64s(f, v);
1030     return 0;
1031 }
1032
1033 static void put_uint64(QEMUFile *f, void *pv, size_t size)
1034 {
1035     uint64_t *v = pv;
1036     qemu_put_be64s(f, v);
1037 }
1038
1039 const VMStateInfo vmstate_info_uint64 = {
1040     .name = "uint64",
1041     .get  = get_uint64,
1042     .put  = put_uint64,
1043 };
1044
1045 /* 8 bit int. See that the received value is the same than the one
1046    in the field */
1047
1048 static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
1049 {
1050     uint8_t *v = pv;
1051     uint8_t v2;
1052     qemu_get_8s(f, &v2);
1053
1054     if (*v == v2)
1055         return 0;
1056     return -EINVAL;
1057 }
1058
1059 const VMStateInfo vmstate_info_uint8_equal = {
1060     .name = "uint8 equal",
1061     .get  = get_uint8_equal,
1062     .put  = put_uint8,
1063 };
1064
1065 /* 16 bit unsigned int int. See that the received value is the same than the one
1066    in the field */
1067
1068 static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
1069 {
1070     uint16_t *v = pv;
1071     uint16_t v2;
1072     qemu_get_be16s(f, &v2);
1073
1074     if (*v == v2)
1075         return 0;
1076     return -EINVAL;
1077 }
1078
1079 const VMStateInfo vmstate_info_uint16_equal = {
1080     .name = "uint16 equal",
1081     .get  = get_uint16_equal,
1082     .put  = put_uint16,
1083 };
1084
1085 /* timers  */
1086
1087 static int get_timer(QEMUFile *f, void *pv, size_t size)
1088 {
1089     QEMUTimer *v = pv;
1090     qemu_get_timer(f, v);
1091     return 0;
1092 }
1093
1094 static void put_timer(QEMUFile *f, void *pv, size_t size)
1095 {
1096     QEMUTimer *v = pv;
1097     qemu_put_timer(f, v);
1098 }
1099
1100 const VMStateInfo vmstate_info_timer = {
1101     .name = "timer",
1102     .get  = get_timer,
1103     .put  = put_timer,
1104 };
1105
1106 /* uint8_t buffers */
1107
1108 static int get_buffer(QEMUFile *f, void *pv, size_t size)
1109 {
1110     uint8_t *v = pv;
1111     qemu_get_buffer(f, v, size);
1112     return 0;
1113 }
1114
1115 static void put_buffer(QEMUFile *f, void *pv, size_t size)
1116 {
1117     uint8_t *v = pv;
1118     qemu_put_buffer(f, v, size);
1119 }
1120
1121 const VMStateInfo vmstate_info_buffer = {
1122     .name = "buffer",
1123     .get  = get_buffer,
1124     .put  = put_buffer,
1125 };
1126
1127 /* unused buffers: space that was used for some fields that are
1128    not useful anymore */
1129
1130 static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
1131 {
1132     uint8_t buf[1024];
1133     int block_len;
1134
1135     while (size > 0) {
1136         block_len = MIN(sizeof(buf), size);
1137         size -= block_len;
1138         qemu_get_buffer(f, buf, block_len);
1139     }
1140    return 0;
1141 }
1142
1143 static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
1144 {
1145     static const uint8_t buf[1024];
1146     int block_len;
1147
1148     while (size > 0) {
1149         block_len = MIN(sizeof(buf), size);
1150         size -= block_len;
1151         qemu_put_buffer(f, buf, block_len);
1152     }
1153 }
1154
1155 const VMStateInfo vmstate_info_unused_buffer = {
1156     .name = "unused_buffer",
1157     .get  = get_unused_buffer,
1158     .put  = put_unused_buffer,
1159 };
1160
1161 typedef struct CompatEntry {
1162     char idstr[256];
1163     int instance_id;
1164 } CompatEntry;
1165
1166 typedef struct SaveStateEntry {
1167     QTAILQ_ENTRY(SaveStateEntry) entry;
1168     char idstr[256];
1169     int instance_id;
1170     int alias_id;
1171     int version_id;
1172     int section_id;
1173     SaveSetParamsHandler *set_params;
1174     SaveLiveStateHandler *save_live_state;
1175     SaveStateHandler *save_state;
1176     LoadStateHandler *load_state;
1177     const VMStateDescription *vmsd;
1178     void *opaque;
1179     CompatEntry *compat;
1180     int no_migrate;
1181     int is_ram;
1182 } SaveStateEntry;
1183
1184
1185 static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
1186     QTAILQ_HEAD_INITIALIZER(savevm_handlers);
1187 static int global_section_id;
1188
1189 static int calculate_new_instance_id(const char *idstr)
1190 {
1191     SaveStateEntry *se;
1192     int instance_id = 0;
1193
1194     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1195         if (strcmp(idstr, se->idstr) == 0
1196             && instance_id <= se->instance_id) {
1197             instance_id = se->instance_id + 1;
1198         }
1199     }
1200     return instance_id;
1201 }
1202
1203 static int calculate_compat_instance_id(const char *idstr)
1204 {
1205     SaveStateEntry *se;
1206     int instance_id = 0;
1207
1208     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1209         if (!se->compat)
1210             continue;
1211
1212         if (strcmp(idstr, se->compat->idstr) == 0
1213             && instance_id <= se->compat->instance_id) {
1214             instance_id = se->compat->instance_id + 1;
1215         }
1216     }
1217     return instance_id;
1218 }
1219
1220 /* TODO: Individual devices generally have very little idea about the rest
1221    of the system, so instance_id should be removed/replaced.
1222    Meanwhile pass -1 as instance_id if you do not already have a clearly
1223    distinguishing id for all instances of your device class. */
1224 int register_savevm_live(DeviceState *dev,
1225                          const char *idstr,
1226                          int instance_id,
1227                          int version_id,
1228                          SaveSetParamsHandler *set_params,
1229                          SaveLiveStateHandler *save_live_state,
1230                          SaveStateHandler *save_state,
1231                          LoadStateHandler *load_state,
1232                          void *opaque)
1233 {
1234     SaveStateEntry *se;
1235
1236     se = g_malloc0(sizeof(SaveStateEntry));
1237     se->version_id = version_id;
1238     se->section_id = global_section_id++;
1239     se->set_params = set_params;
1240     se->save_live_state = save_live_state;
1241     se->save_state = save_state;
1242     se->load_state = load_state;
1243     se->opaque = opaque;
1244     se->vmsd = NULL;
1245     se->no_migrate = 0;
1246     /* if this is a live_savem then set is_ram */
1247     if (save_live_state != NULL) {
1248         se->is_ram = 1;
1249     }
1250
1251     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1252         char *id = dev->parent_bus->info->get_dev_path(dev);
1253         if (id) {
1254             pstrcpy(se->idstr, sizeof(se->idstr), id);
1255             pstrcat(se->idstr, sizeof(se->idstr), "/");
1256             g_free(id);
1257
1258             se->compat = g_malloc0(sizeof(CompatEntry));
1259             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
1260             se->compat->instance_id = instance_id == -1 ?
1261                          calculate_compat_instance_id(idstr) : instance_id;
1262             instance_id = -1;
1263         }
1264     }
1265     pstrcat(se->idstr, sizeof(se->idstr), idstr);
1266
1267     if (instance_id == -1) {
1268         se->instance_id = calculate_new_instance_id(se->idstr);
1269     } else {
1270         se->instance_id = instance_id;
1271     }
1272     assert(!se->compat || se->instance_id == 0);
1273     /* add at the end of list */
1274     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1275     return 0;
1276 }
1277
1278 int register_savevm(DeviceState *dev,
1279                     const char *idstr,
1280                     int instance_id,
1281                     int version_id,
1282                     SaveStateHandler *save_state,
1283                     LoadStateHandler *load_state,
1284                     void *opaque)
1285 {
1286     return register_savevm_live(dev, idstr, instance_id, version_id,
1287                                 NULL, NULL, save_state, load_state, opaque);
1288 }
1289
1290 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
1291 {
1292     SaveStateEntry *se, *new_se;
1293     char id[256] = "";
1294
1295     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1296         char *path = dev->parent_bus->info->get_dev_path(dev);
1297         if (path) {
1298             pstrcpy(id, sizeof(id), path);
1299             pstrcat(id, sizeof(id), "/");
1300             g_free(path);
1301         }
1302     }
1303     pstrcat(id, sizeof(id), idstr);
1304
1305     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1306         if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1307             QTAILQ_REMOVE(&savevm_handlers, se, entry);
1308             if (se->compat) {
1309                 g_free(se->compat);
1310             }
1311             g_free(se);
1312         }
1313     }
1314 }
1315
1316 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
1317                                    const VMStateDescription *vmsd,
1318                                    void *opaque, int alias_id,
1319                                    int required_for_version)
1320 {
1321     SaveStateEntry *se;
1322
1323     /* If this triggers, alias support can be dropped for the vmsd. */
1324     assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);
1325
1326     se = g_malloc0(sizeof(SaveStateEntry));
1327     se->version_id = vmsd->version_id;
1328     se->section_id = global_section_id++;
1329     se->save_live_state = NULL;
1330     se->save_state = NULL;
1331     se->load_state = NULL;
1332     se->opaque = opaque;
1333     se->vmsd = vmsd;
1334     se->alias_id = alias_id;
1335     se->no_migrate = vmsd->unmigratable;
1336
1337     if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
1338         char *id = dev->parent_bus->info->get_dev_path(dev);
1339         if (id) {
1340             pstrcpy(se->idstr, sizeof(se->idstr), id);
1341             pstrcat(se->idstr, sizeof(se->idstr), "/");
1342             g_free(id);
1343
1344             se->compat = g_malloc0(sizeof(CompatEntry));
1345             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
1346             se->compat->instance_id = instance_id == -1 ?
1347                          calculate_compat_instance_id(vmsd->name) : instance_id;
1348             instance_id = -1;
1349         }
1350     }
1351     pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
1352
1353     if (instance_id == -1) {
1354         se->instance_id = calculate_new_instance_id(se->idstr);
1355     } else {
1356         se->instance_id = instance_id;
1357     }
1358     assert(!se->compat || se->instance_id == 0);
1359     /* add at the end of list */
1360     QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1361     return 0;
1362 }
1363
1364 int vmstate_register(DeviceState *dev, int instance_id,
1365                      const VMStateDescription *vmsd, void *opaque)
1366 {
1367     return vmstate_register_with_alias_id(dev, instance_id, vmsd,
1368                                           opaque, -1, 0);
1369 }
1370
1371 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
1372                         void *opaque)
1373 {
1374     SaveStateEntry *se, *new_se;
1375
1376     QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1377         if (se->vmsd == vmsd && se->opaque == opaque) {
1378             QTAILQ_REMOVE(&savevm_handlers, se, entry);
1379             if (se->compat) {
1380                 g_free(se->compat);
1381             }
1382             g_free(se);
1383         }
1384     }
1385 }
1386
1387 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1388                                     void *opaque);
1389 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1390                                    void *opaque);
1391
1392 int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
1393                        void *opaque, int version_id)
1394 {
1395     VMStateField *field = vmsd->fields;
1396     int ret;
1397
1398     if (version_id > vmsd->version_id) {
1399         return -EINVAL;
1400     }
1401     if (version_id < vmsd->minimum_version_id_old) {
1402         return -EINVAL;
1403     }
1404     if  (version_id < vmsd->minimum_version_id) {
1405         return vmsd->load_state_old(f, opaque, version_id);
1406     }
1407     if (vmsd->pre_load) {
1408         int ret = vmsd->pre_load(opaque);
1409         if (ret)
1410             return ret;
1411     }
1412     while(field->name) {
1413         if ((field->field_exists &&
1414              field->field_exists(opaque, version_id)) ||
1415             (!field->field_exists &&
1416              field->version_id <= version_id)) {
1417             void *base_addr = opaque + field->offset;
1418             int i, n_elems = 1;
1419             int size = field->size;
1420
1421             if (field->flags & VMS_VBUFFER) {
1422                 size = *(int32_t *)(opaque+field->size_offset);
1423                 if (field->flags & VMS_MULTIPLY) {
1424                     size *= field->size;
1425                 }
1426             }
1427             if (field->flags & VMS_ARRAY) {
1428                 n_elems = field->num;
1429             } else if (field->flags & VMS_VARRAY_INT32) {
1430                 n_elems = *(int32_t *)(opaque+field->num_offset);
1431             } else if (field->flags & VMS_VARRAY_UINT32) {
1432                 n_elems = *(uint32_t *)(opaque+field->num_offset);
1433             } else if (field->flags & VMS_VARRAY_UINT16) {
1434                 n_elems = *(uint16_t *)(opaque+field->num_offset);
1435             } else if (field->flags & VMS_VARRAY_UINT8) {
1436                 n_elems = *(uint8_t *)(opaque+field->num_offset);
1437             }
1438             if (field->flags & VMS_POINTER) {
1439                 base_addr = *(void **)base_addr + field->start;
1440             }
1441             for (i = 0; i < n_elems; i++) {
1442                 void *addr = base_addr + size * i;
1443
1444                 if (field->flags & VMS_ARRAY_OF_POINTER) {
1445                     addr = *(void **)addr;
1446                 }
1447                 if (field->flags & VMS_STRUCT) {
1448                     ret = vmstate_load_state(f, field->vmsd, addr, field->vmsd->version_id);
1449                 } else {
1450                     ret = field->info->get(f, addr, size);
1451
1452                 }
1453                 if (ret < 0) {
1454                     return ret;
1455                 }
1456             }
1457         }
1458         field++;
1459     }
1460     ret = vmstate_subsection_load(f, vmsd, opaque);
1461     if (ret != 0) {
1462         return ret;
1463     }
1464     if (vmsd->post_load) {
1465         return vmsd->post_load(opaque, version_id);
1466     }
1467     return 0;
1468 }
1469
1470 void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
1471                         void *opaque)
1472 {
1473     VMStateField *field = vmsd->fields;
1474
1475     if (vmsd->pre_save) {
1476         vmsd->pre_save(opaque);
1477     }
1478     while(field->name) {
1479         if (!field->field_exists ||
1480             field->field_exists(opaque, vmsd->version_id)) {
1481             void *base_addr = opaque + field->offset;
1482             int i, n_elems = 1;
1483             int size = field->size;
1484
1485             if (field->flags & VMS_VBUFFER) {
1486                 size = *(int32_t *)(opaque+field->size_offset);
1487                 if (field->flags & VMS_MULTIPLY) {
1488                     size *= field->size;
1489                 }
1490             }
1491             if (field->flags & VMS_ARRAY) {
1492                 n_elems = field->num;
1493             } else if (field->flags & VMS_VARRAY_INT32) {
1494                 n_elems = *(int32_t *)(opaque+field->num_offset);
1495             } else if (field->flags & VMS_VARRAY_UINT32) {
1496                 n_elems = *(uint32_t *)(opaque+field->num_offset);
1497             } else if (field->flags & VMS_VARRAY_UINT16) {
1498                 n_elems = *(uint16_t *)(opaque+field->num_offset);
1499             } else if (field->flags & VMS_VARRAY_UINT8) {
1500                 n_elems = *(uint8_t *)(opaque+field->num_offset);
1501             }
1502             if (field->flags & VMS_POINTER) {
1503                 base_addr = *(void **)base_addr + field->start;
1504             }
1505             for (i = 0; i < n_elems; i++) {
1506                 void *addr = base_addr + size * i;
1507
1508                 if (field->flags & VMS_ARRAY_OF_POINTER) {
1509                     addr = *(void **)addr;
1510                 }
1511                 if (field->flags & VMS_STRUCT) {
1512                     vmstate_save_state(f, field->vmsd, addr);
1513                 } else {
1514                     field->info->put(f, addr, size);
1515                 }
1516             }
1517         }
1518         field++;
1519     }
1520     vmstate_subsection_save(f, vmsd, opaque);
1521 }
1522
1523 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
1524 {
1525     if (!se->vmsd) {         /* Old style */
1526         return se->load_state(f, se->opaque, version_id);
1527     }
1528     return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
1529 }
1530
1531 static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
1532 {
1533     if (!se->vmsd) {         /* Old style */
1534         se->save_state(f, se->opaque);
1535         return;
1536     }
1537     vmstate_save_state(f,se->vmsd, se->opaque);
1538 }
1539
1540 #define QEMU_VM_FILE_MAGIC           0x5145564d
1541 #define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
1542 #define QEMU_VM_FILE_VERSION         0x00000003
1543
1544 #define QEMU_VM_EOF                  0x00
1545 #define QEMU_VM_SECTION_START        0x01
1546 #define QEMU_VM_SECTION_PART         0x02
1547 #define QEMU_VM_SECTION_END          0x03
1548 #define QEMU_VM_SECTION_FULL         0x04
1549 #define QEMU_VM_SUBSECTION           0x05
1550
1551 bool qemu_savevm_state_blocked(Error **errp)
1552 {
1553     SaveStateEntry *se;
1554
1555     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1556         if (se->no_migrate) {
1557             error_set(errp, QERR_MIGRATION_NOT_SUPPORTED, se->idstr);
1558             return true;
1559         }
1560     }
1561     return false;
1562 }
1563
1564 int qemu_savevm_state_begin(QEMUFile *f, int blk_enable, int shared)
1565 {
1566     SaveStateEntry *se;
1567     int ret;
1568
1569     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1570         if(se->set_params == NULL) {
1571             continue;
1572         }
1573         se->set_params(blk_enable, shared, se->opaque);
1574     }
1575
1576     qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1577     qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1578
1579     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1580         int len;
1581
1582         if (se->save_live_state == NULL)
1583             continue;
1584
1585         /* Section type */
1586         qemu_put_byte(f, QEMU_VM_SECTION_START);
1587         qemu_put_be32(f, se->section_id);
1588
1589         /* ID string */
1590         len = strlen(se->idstr);
1591         qemu_put_byte(f, len);
1592         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1593
1594         qemu_put_be32(f, se->instance_id);
1595         qemu_put_be32(f, se->version_id);
1596
1597         ret = se->save_live_state(f, QEMU_VM_SECTION_START, se->opaque);
1598         if (ret < 0) {
1599             qemu_savevm_state_cancel(f);
1600             return ret;
1601         }
1602     }
1603     ret = qemu_file_get_error(f);
1604     if (ret != 0) {
1605         qemu_savevm_state_cancel(f);
1606     }
1607
1608     return ret;
1609
1610 }
1611
1612 /*
1613  * this function has three return values:
1614  *   negative: there was one error, and we have -errno.
1615  *   0 : We haven't finished, caller have to go again
1616  *   1 : We have finished, we can go to complete phase
1617  */
1618 int qemu_savevm_state_iterate(QEMUFile *f)
1619 {
1620     SaveStateEntry *se;
1621     int ret = 1;
1622
1623     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1624         if (se->save_live_state == NULL)
1625             continue;
1626
1627         /* Section type */
1628         qemu_put_byte(f, QEMU_VM_SECTION_PART);
1629         qemu_put_be32(f, se->section_id);
1630
1631         ret = se->save_live_state(f, QEMU_VM_SECTION_PART, se->opaque);
1632         if (ret <= 0) {
1633             /* Do not proceed to the next vmstate before this one reported
1634                completion of the current stage. This serializes the migration
1635                and reduces the probability that a faster changing state is
1636                synchronized over and over again. */
1637             break;
1638         }
1639     }
1640     if (ret != 0) {
1641         return ret;
1642     }
1643     ret = qemu_file_get_error(f);
1644     if (ret != 0) {
1645         qemu_savevm_state_cancel(f);
1646     }
1647     return ret;
1648 }
1649
1650 int qemu_savevm_state_complete(QEMUFile *f)
1651 {
1652     SaveStateEntry *se;
1653     int ret;
1654
1655     cpu_synchronize_all_states();
1656
1657     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1658         if (se->save_live_state == NULL)
1659             continue;
1660
1661         /* Section type */
1662         qemu_put_byte(f, QEMU_VM_SECTION_END);
1663         qemu_put_be32(f, se->section_id);
1664
1665         ret = se->save_live_state(f, QEMU_VM_SECTION_END, se->opaque);
1666         if (ret < 0) {
1667             return ret;
1668         }
1669     }
1670
1671     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1672         int len;
1673
1674         if (se->save_state == NULL && se->vmsd == NULL)
1675             continue;
1676
1677         /* Section type */
1678         qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1679         qemu_put_be32(f, se->section_id);
1680
1681         /* ID string */
1682         len = strlen(se->idstr);
1683         qemu_put_byte(f, len);
1684         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1685
1686         qemu_put_be32(f, se->instance_id);
1687         qemu_put_be32(f, se->version_id);
1688
1689         vmstate_save(f, se);
1690     }
1691
1692     qemu_put_byte(f, QEMU_VM_EOF);
1693
1694     return qemu_file_get_error(f);
1695 }
1696
1697 void qemu_savevm_state_cancel(QEMUFile *f)
1698 {
1699     SaveStateEntry *se;
1700
1701     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1702         if (se->save_live_state) {
1703             se->save_live_state(f, -1, se->opaque);
1704         }
1705     }
1706 }
1707
1708 static int qemu_savevm_state(QEMUFile *f)
1709 {
1710     int ret;
1711
1712     if (qemu_savevm_state_blocked(NULL)) {
1713         ret = -EINVAL;
1714         goto out;
1715     }
1716
1717     ret = qemu_savevm_state_begin(f, 0, 0);
1718     if (ret < 0)
1719         goto out;
1720
1721     do {
1722         ret = qemu_savevm_state_iterate(f);
1723         if (ret < 0)
1724             goto out;
1725     } while (ret == 0);
1726
1727     ret = qemu_savevm_state_complete(f);
1728
1729 out:
1730     if (ret == 0) {
1731         ret = qemu_file_get_error(f);
1732     }
1733
1734     return ret;
1735 }
1736
1737 static int qemu_save_device_state(QEMUFile *f)
1738 {
1739     SaveStateEntry *se;
1740
1741     qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1742     qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1743
1744     cpu_synchronize_all_states();
1745
1746     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1747         int len;
1748
1749         if (se->is_ram) {
1750             continue;
1751         }
1752         if (se->save_state == NULL && se->vmsd == NULL) {
1753             continue;
1754         }
1755
1756         /* Section type */
1757         qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1758         qemu_put_be32(f, se->section_id);
1759
1760         /* ID string */
1761         len = strlen(se->idstr);
1762         qemu_put_byte(f, len);
1763         qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1764
1765         qemu_put_be32(f, se->instance_id);
1766         qemu_put_be32(f, se->version_id);
1767
1768         vmstate_save(f, se);
1769     }
1770
1771     qemu_put_byte(f, QEMU_VM_EOF);
1772
1773     return qemu_file_get_error(f);
1774 }
1775
1776 static SaveStateEntry *find_se(const char *idstr, int instance_id)
1777 {
1778     SaveStateEntry *se;
1779
1780     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1781         if (!strcmp(se->idstr, idstr) &&
1782             (instance_id == se->instance_id ||
1783              instance_id == se->alias_id))
1784             return se;
1785         /* Migrating from an older version? */
1786         if (strstr(se->idstr, idstr) && se->compat) {
1787             if (!strcmp(se->compat->idstr, idstr) &&
1788                 (instance_id == se->compat->instance_id ||
1789                  instance_id == se->alias_id))
1790                 return se;
1791         }
1792     }
1793     return NULL;
1794 }
1795
1796 static const VMStateDescription *vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
1797 {
1798     while(sub && sub->needed) {
1799         if (strcmp(idstr, sub->vmsd->name) == 0) {
1800             return sub->vmsd;
1801         }
1802         sub++;
1803     }
1804     return NULL;
1805 }
1806
1807 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1808                                    void *opaque)
1809 {
1810     while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
1811         char idstr[256];
1812         int ret;
1813         uint8_t version_id, len, size;
1814         const VMStateDescription *sub_vmsd;
1815
1816         len = qemu_peek_byte(f, 1);
1817         if (len < strlen(vmsd->name) + 1) {
1818             /* subsection name has be be "section_name/a" */
1819             return 0;
1820         }
1821         size = qemu_peek_buffer(f, (uint8_t *)idstr, len, 2);
1822         if (size != len) {
1823             return 0;
1824         }
1825         idstr[size] = 0;
1826
1827         if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
1828             /* it don't have a valid subsection name */
1829             return 0;
1830         }
1831         sub_vmsd = vmstate_get_subsection(vmsd->subsections, idstr);
1832         if (sub_vmsd == NULL) {
1833             return -ENOENT;
1834         }
1835         qemu_file_skip(f, 1); /* subsection */
1836         qemu_file_skip(f, 1); /* len */
1837         qemu_file_skip(f, len); /* idstr */
1838         version_id = qemu_get_be32(f);
1839
1840         ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
1841         if (ret) {
1842             return ret;
1843         }
1844     }
1845     return 0;
1846 }
1847
1848 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1849                                     void *opaque)
1850 {
1851     const VMStateSubsection *sub = vmsd->subsections;
1852
1853     while (sub && sub->needed) {
1854         if (sub->needed(opaque)) {
1855             const VMStateDescription *vmsd = sub->vmsd;
1856             uint8_t len;
1857
1858             qemu_put_byte(f, QEMU_VM_SUBSECTION);
1859             len = strlen(vmsd->name);
1860             qemu_put_byte(f, len);
1861             qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
1862             qemu_put_be32(f, vmsd->version_id);
1863             vmstate_save_state(f, vmsd, opaque);
1864         }
1865         sub++;
1866     }
1867 }
1868
1869 typedef struct LoadStateEntry {
1870     QLIST_ENTRY(LoadStateEntry) entry;
1871     SaveStateEntry *se;
1872     int section_id;
1873     int version_id;
1874 } LoadStateEntry;
1875
1876 int qemu_loadvm_state(QEMUFile *f)
1877 {
1878     QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
1879         QLIST_HEAD_INITIALIZER(loadvm_handlers);
1880     LoadStateEntry *le, *new_le;
1881     uint8_t section_type;
1882     unsigned int v;
1883     int ret;
1884
1885     if (qemu_savevm_state_blocked(NULL)) {
1886         return -EINVAL;
1887     }
1888
1889     v = qemu_get_be32(f);
1890     if (v != QEMU_VM_FILE_MAGIC)
1891         return -EINVAL;
1892
1893     v = qemu_get_be32(f);
1894     if (v == QEMU_VM_FILE_VERSION_COMPAT) {
1895         fprintf(stderr, "SaveVM v2 format is obsolete and don't work anymore\n");
1896         return -ENOTSUP;
1897     }
1898     if (v != QEMU_VM_FILE_VERSION)
1899         return -ENOTSUP;
1900
1901     while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
1902         uint32_t instance_id, version_id, section_id;
1903         SaveStateEntry *se;
1904         char idstr[257];
1905         int len;
1906
1907         switch (section_type) {
1908         case QEMU_VM_SECTION_START:
1909         case QEMU_VM_SECTION_FULL:
1910             /* Read section start */
1911             section_id = qemu_get_be32(f);
1912             len = qemu_get_byte(f);
1913             qemu_get_buffer(f, (uint8_t *)idstr, len);
1914             idstr[len] = 0;
1915             instance_id = qemu_get_be32(f);
1916             version_id = qemu_get_be32(f);
1917
1918             /* Find savevm section */
1919             se = find_se(idstr, instance_id);
1920             if (se == NULL) {
1921                 fprintf(stderr, "Unknown savevm section or instance '%s' %d\n", idstr, instance_id);
1922                 ret = -EINVAL;
1923                 goto out;
1924             }
1925
1926             /* Validate version */
1927             if (version_id > se->version_id) {
1928                 fprintf(stderr, "savevm: unsupported version %d for '%s' v%d\n",
1929                         version_id, idstr, se->version_id);
1930                 ret = -EINVAL;
1931                 goto out;
1932             }
1933
1934             /* Add entry */
1935             le = g_malloc0(sizeof(*le));
1936
1937             le->se = se;
1938             le->section_id = section_id;
1939             le->version_id = version_id;
1940             QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
1941
1942             ret = vmstate_load(f, le->se, le->version_id);
1943             if (ret < 0) {
1944                 fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
1945                         instance_id, idstr);
1946                 goto out;
1947             }
1948             break;
1949         case QEMU_VM_SECTION_PART:
1950         case QEMU_VM_SECTION_END:
1951             section_id = qemu_get_be32(f);
1952
1953             QLIST_FOREACH(le, &loadvm_handlers, entry) {
1954                 if (le->section_id == section_id) {
1955                     break;
1956                 }
1957             }
1958             if (le == NULL) {
1959                 fprintf(stderr, "Unknown savevm section %d\n", section_id);
1960                 ret = -EINVAL;
1961                 goto out;
1962             }
1963
1964             ret = vmstate_load(f, le->se, le->version_id);
1965             if (ret < 0) {
1966                 fprintf(stderr, "qemu: warning: error while loading state section id %d\n",
1967                         section_id);
1968                 goto out;
1969             }
1970             break;
1971         default:
1972             fprintf(stderr, "Unknown savevm section type %d\n", section_type);
1973             ret = -EINVAL;
1974             goto out;
1975         }
1976     }
1977
1978     cpu_synchronize_all_post_init();
1979
1980     ret = 0;
1981
1982 out:
1983     QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
1984         QLIST_REMOVE(le, entry);
1985         g_free(le);
1986     }
1987
1988     if (ret == 0) {
1989         ret = qemu_file_get_error(f);
1990     }
1991
1992     return ret;
1993 }
1994
1995 static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
1996                               const char *name)
1997 {
1998     QEMUSnapshotInfo *sn_tab, *sn;
1999     int nb_sns, i, ret;
2000
2001     ret = -ENOENT;
2002     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2003     if (nb_sns < 0)
2004         return ret;
2005     for(i = 0; i < nb_sns; i++) {
2006         sn = &sn_tab[i];
2007         if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
2008             *sn_info = *sn;
2009             ret = 0;
2010             break;
2011         }
2012     }
2013     g_free(sn_tab);
2014     return ret;
2015 }
2016
2017 /*
2018  * Deletes snapshots of a given name in all opened images.
2019  */
2020 static int del_existing_snapshots(Monitor *mon, const char *name)
2021 {
2022     BlockDriverState *bs;
2023     QEMUSnapshotInfo sn1, *snapshot = &sn1;
2024     int ret;
2025
2026     bs = NULL;
2027     while ((bs = bdrv_next(bs))) {
2028         if (bdrv_can_snapshot(bs) &&
2029             bdrv_snapshot_find(bs, snapshot, name) >= 0)
2030         {
2031             ret = bdrv_snapshot_delete(bs, name);
2032             if (ret < 0) {
2033                 monitor_printf(mon,
2034                                "Error while deleting snapshot on '%s'\n",
2035                                bdrv_get_device_name(bs));
2036                 return -1;
2037             }
2038         }
2039     }
2040
2041     return 0;
2042 }
2043
2044 void do_savevm(Monitor *mon, const QDict *qdict)
2045 {
2046     BlockDriverState *bs, *bs1;
2047     QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
2048     int ret;
2049     QEMUFile *f;
2050     int saved_vm_running;
2051     uint64_t vm_state_size;
2052 #ifdef _WIN32
2053     struct _timeb tb;
2054     struct tm *ptm;
2055 #else
2056     struct timeval tv;
2057     struct tm tm;
2058 #endif
2059     const char *name = qdict_get_try_str(qdict, "name");
2060
2061     /* Verify if there is a device that doesn't support snapshots and is writable */
2062     bs = NULL;
2063     while ((bs = bdrv_next(bs))) {
2064
2065         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2066             continue;
2067         }
2068
2069         if (!bdrv_can_snapshot(bs)) {
2070             monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
2071                                bdrv_get_device_name(bs));
2072             return;
2073         }
2074     }
2075
2076     bs = bdrv_snapshots();
2077     if (!bs) {
2078         monitor_printf(mon, "No block device can accept snapshots\n");
2079         return;
2080     }
2081
2082     saved_vm_running = runstate_is_running();
2083     vm_stop(RUN_STATE_SAVE_VM);
2084
2085     memset(sn, 0, sizeof(*sn));
2086
2087     /* fill auxiliary fields */
2088 #ifdef _WIN32
2089     _ftime(&tb);
2090     sn->date_sec = tb.time;
2091     sn->date_nsec = tb.millitm * 1000000;
2092 #else
2093     gettimeofday(&tv, NULL);
2094     sn->date_sec = tv.tv_sec;
2095     sn->date_nsec = tv.tv_usec * 1000;
2096 #endif
2097     sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
2098
2099     if (name) {
2100         ret = bdrv_snapshot_find(bs, old_sn, name);
2101         if (ret >= 0) {
2102             pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
2103             pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
2104         } else {
2105             pstrcpy(sn->name, sizeof(sn->name), name);
2106         }
2107     } else {
2108 #ifdef _WIN32
2109         ptm = localtime(&tb.time);
2110         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", ptm);
2111 #else
2112         /* cast below needed for OpenBSD where tv_sec is still 'long' */
2113         localtime_r((const time_t *)&tv.tv_sec, &tm);
2114         strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
2115 #endif
2116     }
2117
2118     /* Delete old snapshots of the same name */
2119     if (name && del_existing_snapshots(mon, name) < 0) {
2120         goto the_end;
2121     }
2122
2123     /* save the VM state */
2124     f = qemu_fopen_bdrv(bs, 1);
2125     if (!f) {
2126         monitor_printf(mon, "Could not open VM state file\n");
2127         goto the_end;
2128     }
2129     ret = qemu_savevm_state(f);
2130     vm_state_size = qemu_ftell(f);
2131     qemu_fclose(f);
2132     if (ret < 0) {
2133         monitor_printf(mon, "Error %d while writing VM\n", ret);
2134         goto the_end;
2135     }
2136
2137     /* create the snapshots */
2138
2139     bs1 = NULL;
2140     while ((bs1 = bdrv_next(bs1))) {
2141         if (bdrv_can_snapshot(bs1)) {
2142             /* Write VM state size only to the image that contains the state */
2143             sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
2144             ret = bdrv_snapshot_create(bs1, sn);
2145             if (ret < 0) {
2146                 monitor_printf(mon, "Error while creating snapshot on '%s'\n",
2147                                bdrv_get_device_name(bs1));
2148             }
2149         }
2150     }
2151
2152  the_end:
2153     if (saved_vm_running)
2154         vm_start();
2155 }
2156
2157 void qmp_xen_save_devices_state(const char *filename, Error **errp)
2158 {
2159     QEMUFile *f;
2160     int saved_vm_running;
2161     int ret;
2162
2163     saved_vm_running = runstate_is_running();
2164     vm_stop(RUN_STATE_SAVE_VM);
2165
2166     f = qemu_fopen(filename, "wb");
2167     if (!f) {
2168         error_set(errp, QERR_OPEN_FILE_FAILED, filename);
2169         goto the_end;
2170     }
2171     ret = qemu_save_device_state(f);
2172     qemu_fclose(f);
2173     if (ret < 0) {
2174         error_set(errp, QERR_IO_ERROR);
2175     }
2176
2177  the_end:
2178     if (saved_vm_running)
2179         vm_start();
2180     return;
2181 }
2182
2183 int load_vmstate(const char *name)
2184 {
2185     BlockDriverState *bs, *bs_vm_state;
2186     QEMUSnapshotInfo sn;
2187     QEMUFile *f;
2188     int ret;
2189
2190     bs_vm_state = bdrv_snapshots();
2191     if (!bs_vm_state) {
2192         error_report("No block device supports snapshots");
2193         return -ENOTSUP;
2194     }
2195
2196     /* Don't even try to load empty VM states */
2197     ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
2198     if (ret < 0) {
2199         return ret;
2200     } else if (sn.vm_state_size == 0) {
2201         error_report("This is a disk-only snapshot. Revert to it offline "
2202             "using qemu-img.");
2203         return -EINVAL;
2204     }
2205
2206     /* Verify if there is any device that doesn't support snapshots and is
2207     writable and check if the requested snapshot is available too. */
2208     bs = NULL;
2209     while ((bs = bdrv_next(bs))) {
2210
2211         if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2212             continue;
2213         }
2214
2215         if (!bdrv_can_snapshot(bs)) {
2216             error_report("Device '%s' is writable but does not support snapshots.",
2217                                bdrv_get_device_name(bs));
2218             return -ENOTSUP;
2219         }
2220
2221         ret = bdrv_snapshot_find(bs, &sn, name);
2222         if (ret < 0) {
2223             error_report("Device '%s' does not have the requested snapshot '%s'",
2224                            bdrv_get_device_name(bs), name);
2225             return ret;
2226         }
2227     }
2228
2229     /* Flush all IO requests so they don't interfere with the new state.  */
2230     bdrv_drain_all();
2231
2232     bs = NULL;
2233     while ((bs = bdrv_next(bs))) {
2234         if (bdrv_can_snapshot(bs)) {
2235             ret = bdrv_snapshot_goto(bs, name);
2236             if (ret < 0) {
2237                 error_report("Error %d while activating snapshot '%s' on '%s'",
2238                              ret, name, bdrv_get_device_name(bs));
2239                 return ret;
2240             }
2241         }
2242     }
2243
2244     /* restore the VM state */
2245     f = qemu_fopen_bdrv(bs_vm_state, 0);
2246     if (!f) {
2247         error_report("Could not open VM state file");
2248         return -EINVAL;
2249     }
2250
2251     qemu_system_reset(VMRESET_SILENT);
2252     ret = qemu_loadvm_state(f);
2253
2254     qemu_fclose(f);
2255     if (ret < 0) {
2256         error_report("Error %d while loading VM state", ret);
2257         return ret;
2258     }
2259
2260     return 0;
2261 }
2262
2263 void do_delvm(Monitor *mon, const QDict *qdict)
2264 {
2265     BlockDriverState *bs, *bs1;
2266     int ret;
2267     const char *name = qdict_get_str(qdict, "name");
2268
2269     bs = bdrv_snapshots();
2270     if (!bs) {
2271         monitor_printf(mon, "No block device supports snapshots\n");
2272         return;
2273     }
2274
2275     bs1 = NULL;
2276     while ((bs1 = bdrv_next(bs1))) {
2277         if (bdrv_can_snapshot(bs1)) {
2278             ret = bdrv_snapshot_delete(bs1, name);
2279             if (ret < 0) {
2280                 if (ret == -ENOTSUP)
2281                     monitor_printf(mon,
2282                                    "Snapshots not supported on device '%s'\n",
2283                                    bdrv_get_device_name(bs1));
2284                 else
2285                     monitor_printf(mon, "Error %d while deleting snapshot on "
2286                                    "'%s'\n", ret, bdrv_get_device_name(bs1));
2287             }
2288         }
2289     }
2290 }
2291
2292 void do_info_snapshots(Monitor *mon)
2293 {
2294     BlockDriverState *bs, *bs1;
2295     QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
2296     int nb_sns, i, ret, available;
2297     int total;
2298     int *available_snapshots;
2299     char buf[256];
2300
2301     bs = bdrv_snapshots();
2302     if (!bs) {
2303         monitor_printf(mon, "No available block device supports snapshots\n");
2304         return;
2305     }
2306
2307     nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2308     if (nb_sns < 0) {
2309         monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
2310         return;
2311     }
2312
2313     if (nb_sns == 0) {
2314         monitor_printf(mon, "There is no snapshot available.\n");
2315         return;
2316     }
2317
2318     available_snapshots = g_malloc0(sizeof(int) * nb_sns);
2319     total = 0;
2320     for (i = 0; i < nb_sns; i++) {
2321         sn = &sn_tab[i];
2322         available = 1;
2323         bs1 = NULL;
2324
2325         while ((bs1 = bdrv_next(bs1))) {
2326             if (bdrv_can_snapshot(bs1) && bs1 != bs) {
2327                 ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
2328                 if (ret < 0) {
2329                     available = 0;
2330                     break;
2331                 }
2332             }
2333         }
2334
2335         if (available) {
2336             available_snapshots[total] = i;
2337             total++;
2338         }
2339     }
2340
2341     if (total > 0) {
2342         monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
2343         for (i = 0; i < total; i++) {
2344             sn = &sn_tab[available_snapshots[i]];
2345             monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
2346         }
2347     } else {
2348         monitor_printf(mon, "There is no suitable snapshot available\n");
2349     }
2350
2351     g_free(sn_tab);
2352     g_free(available_snapshots);
2353
2354 }
2355
2356 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev)
2357 {
2358     qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK,
2359                        memory_region_name(mr), dev);
2360 }
2361
2362 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev)
2363 {
2364     /* Nothing do to while the implementation is in RAMBlock */
2365 }
2366
2367 void vmstate_register_ram_global(MemoryRegion *mr)
2368 {
2369     vmstate_register_ram(mr, NULL);
2370 }