debian/patches/internal-snapshot-async.patch

   1 From 46fd4bb673a91d40352c95e9d3f62f63b5021053 Mon Sep 17 00:00:00 2001
   2 From: Stefan Priebe <s.priebe@profihost.ag>
   3 Date: Fri, 29 Nov 2013 22:17:03 +0100
   4 Subject: [PATCH] internal-snapshot-async-qemu1.7.patch
   5
   6 ---
   7  Makefile.objs           |    1 +
   8  block.c                 |    2 +-
   9  hmp-commands.hx         |   34 ++++
  10  hmp.c                   |   57 ++++++
  11  hmp.h                   |    5 +
  12  include/block/block.h   |    1 +
  13  include/sysemu/sysemu.h |    5 +-
  14  monitor.c               |    7 +
  15  qapi-schema.json        |   46 +++++
  16  qemu-options.hx         |   13 ++
  17  qmp-commands.hx         |   31 +++
  18  savevm-async.c          |  478 +++++++++++++++++++++++++++++++++++++++++++++++
  19  savevm.c                |   10 +-
  20  vl.c                    |    9 +
  21  14 files changed, 692 insertions(+), 7 deletions(-)
  22  create mode 100644 savevm-async.c
  23
  24 Index: new/Makefile.objs
  25 ===================================================================
  26 --- new.orig/Makefile.objs      2014-05-05 09:49:29.000000000 +0200
  27 +++ new/Makefile.objs   2014-05-05 09:54:17.000000000 +0200
  28 @@ -55,6 +55,7 @@
  29  common-obj-y += qemu-char.o #aio.o
  30  common-obj-y += block-migration.o
  31  common-obj-y += page_cache.o xbzrle.o
  32 +common-obj-y += savevm-async.o
  33
  34  common-obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o migration-fd.o
  35
  36 Index: new/block.c
  37 ===================================================================
  38 --- new.orig/block.c    2014-05-05 09:49:29.000000000 +0200
  39 +++ new/block.c 2014-05-05 09:54:17.000000000 +0200
  40 @@ -1967,7 +1967,7 @@
  41              bs_new->drv ? bs_new->drv->format_name : "");
  42  }
  43
  44 -static void bdrv_delete(BlockDriverState *bs)
  45 +void bdrv_delete(BlockDriverState *bs)
  46  {
  47      assert(!bs->dev);
  48      assert(!bs->job);
  49 Index: new/hmp-commands.hx
  50 ===================================================================
  51 --- new.orig/hmp-commands.hx    2014-05-05 09:49:29.000000000 +0200
  52 +++ new/hmp-commands.hx 2014-05-05 09:54:17.000000000 +0200
  53 @@ -1777,6 +1777,8 @@
  54  show current migration capabilities
  55  @item info migrate_cache_size
  56  show current migration XBZRLE cache size
  57 +@item info savevm
  58 +show savevm status
  59  @item info balloon
  60  show balloon information
  61  @item info qtree
  62 @@ -1798,3 +1800,35 @@
  63  STEXI
  64  @end table
  65  ETEXI
  66 +
  67 +    {
  68 +        .name       = "savevm-start",
  69 +        .args_type  = "statefile:s?",
  70 +        .params     = "[statefile]",
  71 +        .help       = "Prepare for snapshot and halt VM. Save VM state to statefile.",
  72 +        .mhandler.cmd = hmp_savevm_start,
  73 +    },
  74 +
  75 +    {
  76 +        .name       = "snapshot-drive",
  77 +        .args_type  = "device:s,name:s",
  78 +        .params     = "device name",
  79 +        .help       = "Create internal snapshot.",
  80 +        .mhandler.cmd = hmp_snapshot_drive,
  81 +    },
  82 +
  83 +    {
  84 +        .name       = "delete-drive-snapshot",
  85 +        .args_type  = "device:s,name:s",
  86 +        .params     = "device name",
  87 +        .help       = "Delete internal snapshot.",
  88 +        .mhandler.cmd = hmp_delete_drive_snapshot,
  89 +    },
  90 +
  91 +    {
  92 +        .name       = "savevm-end",
  93 +        .args_type  = "",
  94 +        .params     = "",
  95 +        .help       = "Resume VM after snaphot.",
  96 +        .mhandler.cmd = hmp_savevm_end,
  97 +    },
  98 Index: new/hmp.c
  99 ===================================================================
 100 --- new.orig/hmp.c      2014-05-05 09:49:29.000000000 +0200
 101 +++ new/hmp.c   2014-05-05 09:54:17.000000000 +0200
 102 @@ -1738,3 +1738,60 @@
 103      qmp_object_del(id, &err);
 104      hmp_handle_error(mon, &err);
 105  }
 106 +
 107 +void hmp_savevm_start(Monitor *mon, const QDict *qdict)
 108 +{
 109 +    Error *errp = NULL;
 110 +    const char *statefile = qdict_get_try_str(qdict, "statefile");
 111 +
 112 +    qmp_savevm_start(statefile != NULL, statefile, &errp);
 113 +    hmp_handle_error(mon, &errp);
 114 +}
 115 +
 116 +void hmp_snapshot_drive(Monitor *mon, const QDict *qdict)
 117 +{
 118 +    Error *errp = NULL;
 119 +    const char *name = qdict_get_str(qdict, "name");
 120 +    const char *device = qdict_get_str(qdict, "device");
 121 +
 122 +    qmp_snapshot_drive(device, name, &errp);
 123 +    hmp_handle_error(mon, &errp);
 124 +}
 125 +
 126 +void hmp_delete_drive_snapshot(Monitor *mon, const QDict *qdict)
 127 +{
 128 +    Error *errp = NULL;
 129 +    const char *name = qdict_get_str(qdict, "name");
 130 +    const char *device = qdict_get_str(qdict, "device");
 131 +
 132 +    qmp_delete_drive_snapshot(device, name, &errp);
 133 +    hmp_handle_error(mon, &errp);
 134 +}
 135 +
 136 +void hmp_savevm_end(Monitor *mon, const QDict *qdict)
 137 +{
 138 +    Error *errp = NULL;
 139 +
 140 +    qmp_savevm_end(&errp);
 141 +    hmp_handle_error(mon, &errp);
 142 +}
 143 +
 144 +void hmp_info_savevm(Monitor *mon, const QDict *qdict)
 145 +{
 146 +    SaveVMInfo *info;
 147 +    info = qmp_query_savevm(NULL);
 148 +
 149 +    if (info->has_status) {
 150 +        monitor_printf(mon, "savevm status: %s\n", info->status);
 151 +        monitor_printf(mon, "total time: %" PRIu64 " milliseconds\n",
 152 +                       info->total_time);
 153 +    } else {
 154 +        monitor_printf(mon, "savevm status: not running\n");
 155 +    }
 156 +    if (info->has_bytes) {
 157 +        monitor_printf(mon, "Bytes saved: %"PRIu64"\n", info->bytes);
 158 +    }
 159 +    if (info->has_error) {
 160 +        monitor_printf(mon, "Error: %s\n", info->error);
 161 +    }
 162 +}
 163 Index: new/hmp.h
 164 ===================================================================
 165 --- new.orig/hmp.h      2014-05-05 09:49:29.000000000 +0200
 166 +++ new/hmp.h   2014-05-05 09:54:17.000000000 +0200
 167 @@ -25,6 +25,7 @@
 168  void hmp_info_uuid(Monitor *mon, const QDict *qdict);
 169  void hmp_info_chardev(Monitor *mon, const QDict *qdict);
 170  void hmp_info_mice(Monitor *mon, const QDict *qdict);
 171 +void hmp_info_savevm(Monitor *mon, const QDict *qdict);
 172  void hmp_info_migrate(Monitor *mon, const QDict *qdict);
 173  void hmp_info_migrate_capabilities(Monitor *mon, const QDict *qdict);
 174  void hmp_info_migrate_cache_size(Monitor *mon, const QDict *qdict);
 175 @@ -84,6 +85,10 @@
 176  void hmp_netdev_del(Monitor *mon, const QDict *qdict);
 177  void hmp_getfd(Monitor *mon, const QDict *qdict);
 178  void hmp_closefd(Monitor *mon, const QDict *qdict);
 179 +void hmp_savevm_start(Monitor *mon, const QDict *qdict);
 180 +void hmp_snapshot_drive(Monitor *mon, const QDict *qdict);
 181 +void hmp_delete_drive_snapshot(Monitor *mon, const QDict *qdict);
 182 +void hmp_savevm_end(Monitor *mon, const QDict *qdict);
 183  void hmp_send_key(Monitor *mon, const QDict *qdict);
 184  void hmp_screen_dump(Monitor *mon, const QDict *qdict);
 185  void hmp_nbd_server_start(Monitor *mon, const QDict *qdict);
 186 Index: new/include/block/block.h
 187 ===================================================================
 188 --- new.orig/include/block/block.h      2014-05-05 09:49:29.000000000 +0200
 189 +++ new/include/block/block.h   2014-05-05 09:54:17.000000000 +0200
 190 @@ -251,6 +251,7 @@
 191      const char *backing_file);
 192  int bdrv_get_backing_file_depth(BlockDriverState *bs);
 193  int bdrv_truncate(BlockDriverState *bs, int64_t offset);
 194 +void bdrv_delete(BlockDriverState *bs);
 195  int64_t bdrv_getlength(BlockDriverState *bs);
 196  int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
 197  void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
 198 Index: new/include/sysemu/sysemu.h
 199 ===================================================================
 200 --- new.orig/include/sysemu/sysemu.h    2014-05-05 09:49:29.000000000 +0200
 201 +++ new/include/sysemu/sysemu.h 2014-05-05 09:54:17.000000000 +0200
 202 @@ -73,16 +73,17 @@
 203
 204  void do_savevm(Monitor *mon, const QDict *qdict);
 205  int load_vmstate(const char *name);
 206 +int load_state_from_blockdev(const char *filename);
 207  void do_delvm(Monitor *mon, const QDict *qdict);
 208  void do_info_snapshots(Monitor *mon, const QDict *qdict);
 209
 210  void qemu_announce_self(void);
 211
 212  bool qemu_savevm_state_blocked(Error **errp);
 213 -void qemu_savevm_state_begin(QEMUFile *f,
 214 +int qemu_savevm_state_begin(QEMUFile *f,
 215                               const MigrationParams *params);
 216  int qemu_savevm_state_iterate(QEMUFile *f);
 217 -void qemu_savevm_state_complete(QEMUFile *f);
 218 +int qemu_savevm_state_complete(QEMUFile *f);
 219  void qemu_savevm_state_cancel(void);
 220  uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size);
 221  int qemu_loadvm_state(QEMUFile *f);
 222 Index: new/monitor.c
 223 ===================================================================
 224 --- new.orig/monitor.c  2014-05-05 09:49:29.000000000 +0200
 225 +++ new/monitor.c       2014-05-05 09:54:17.000000000 +0200
 226 @@ -2931,6 +2931,13 @@
 227          .mhandler.cmd = hmp_info_migrate_cache_size,
 228      },
 229      {
 230 +        .name       = "savevm",
 231 +        .args_type  = "",
 232 +        .params     = "",
 233 +        .help       = "show savevm status",
 234 +        .mhandler.cmd = hmp_info_savevm,
 235 +    },
 236 +    {
 237          .name       = "balloon",
 238          .args_type  = "",
 239          .params     = "",
 240 Index: new/qapi-schema.json
 241 ===================================================================
 242 --- new.orig/qapi-schema.json   2014-05-05 09:49:29.000000000 +0200
 243 +++ new/qapi-schema.json        2014-05-05 09:54:17.000000000 +0200
 244 @@ -820,6 +820,42 @@
 245             '*downtime': 'int',
 246             '*setup-time': 'int'} }
 247
 248 +
 249 +# @SaveVMInfo
 250 +#
 251 +# Information about current migration process.
 252 +#
 253 +# @status: #optional string describing the current savevm status.
 254 +#          This can be 'active', 'completed', 'failed'.
 255 +#          If this field is not returned, no savevm process
 256 +#          has been initiated
 257 +#
 258 +# @error: #optional string containing error message is status is failed.
 259 +#
 260 +# @total-time: #optional total amount of milliseconds since savevm started.
 261 +#        If savevm has ended, it returns the total save time
 262 +#
 263 +# @bytes: #optional total amount of data transfered
 264 +#
 265 +# Since: 1.3
 266 +##
 267 +{ 'type': 'SaveVMInfo',
 268 +  'data': {'*status': 'str', '*error': 'str',
 269 +           '*total-time': 'int', '*bytes': 'int'} }
 270 +
 271 +##
 272 +# @query-savevm
 273 +#
 274 +# Returns information about current savevm process.
 275 +#
 276 +# Returns: @SaveVMInfo
 277 +#
 278 +# Since: 1.3
 279 +##
 280 +{ 'command': 'query-savevm', 'returns': 'SaveVMInfo' }
 281 +
 282 +##
 283 +
 284  ##
 285  # @query-migrate
 286  #
 287 @@ -3687,8 +3723,18 @@
 288  #
 289  # Since: 1.2.0
 290  ##
 291 +
 292  { 'command': 'query-target', 'returns': 'TargetInfo' }
 293
 294 +{ 'command': 'savevm-start', 'data': { '*statefile': 'str' } }
 295 +
 296 +{ 'command': 'snapshot-drive', 'data': { 'device': 'str', 'name': 'str' } }
 297 +
 298 +{ 'command': 'delete-drive-snapshot', 'data': { 'device': 'str', 'name': 'str' } }
 299 +
 300 +{ 'command': 'savevm-end' }
 301 +
 302 +
 303  ##
 304  # @QKeyCode:
 305  #
 306 Index: new/qemu-options.hx
 307 ===================================================================
 308 --- new.orig/qemu-options.hx    2014-05-05 09:49:29.000000000 +0200
 309 +++ new/qemu-options.hx 2014-05-05 09:54:17.000000000 +0200
 310 @@ -2759,6 +2759,19 @@
 311  Start right away with a saved state (@code{loadvm} in monitor)
 312  ETEXI
 313
 314 +DEF("loadstate", HAS_ARG, QEMU_OPTION_loadstate, \
 315 +    "-loadstate file\n" \
 316 +    "                start right away with a saved state\n",
 317 +    QEMU_ARCH_ALL)
 318 +STEXI
 319 +@item -loadstate @var{file}
 320 +@findex -loadstate
 321 +Start right away with a saved state. This option does not rollback
 322 +disk state like @code{loadvm}, so user must make sure that disk
 323 +have correct state. @var{file} can be any valid device URL. See the section
 324 +for "Device URL Syntax" for more information.
 325 +ETEXI
 326 +
 327  #ifndef _WIN32
 328  DEF("daemonize", 0, QEMU_OPTION_daemonize, \
 329      "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
 330 Index: new/qmp-commands.hx
 331 ===================================================================
 332 --- new.orig/qmp-commands.hx    2014-05-05 09:49:29.000000000 +0200
 333 +++ new/qmp-commands.hx 2014-05-05 09:54:17.000000000 +0200
 334 @@ -3593,3 +3593,34 @@
 335                     } } ] }
 336
 337  EQMP
 338 +
 339 +
 340 +    {
 341 +        .name       = "savevm-start",
 342 +        .args_type  = "statefile:s?",
 343 +        .mhandler.cmd_new = qmp_marshal_input_savevm_start,
 344 +    },
 345 +
 346 +    {
 347 +        .name       = "snapshot-drive",
 348 +        .args_type  = "device:s,name:s",
 349 +        .mhandler.cmd_new = qmp_marshal_input_snapshot_drive,
 350 +    },
 351 +
 352 +    {
 353 +        .name       = "delete-drive-snapshot",
 354 +        .args_type  = "device:s,name:s",
 355 +        .mhandler.cmd_new = qmp_marshal_input_delete_drive_snapshot,
 356 +    },
 357 +
 358 +    {
 359 +        .name       = "savevm-end",
 360 +        .args_type  = "",
 361 +        .mhandler.cmd_new = qmp_marshal_input_savevm_end,
 362 +    },
 363 +
 364 +    {
 365 +        .name       = "query-savevm",
 366 +        .args_type  = "",
 367 +        .mhandler.cmd_new = qmp_marshal_input_query_savevm,
 368 +    },
 369 Index: new/savevm-async.c
 370 ===================================================================
 371 --- /dev/null   1970-01-01 00:00:00.000000000 +0000
 372 +++ new/savevm-async.c  2014-05-05 09:55:53.000000000 +0200
 373 @@ -0,0 +1,478 @@
 374 +#include "qemu-common.h"
 375 +#include "qapi/qmp/qerror.h"
 376 +#include "sysemu/sysemu.h"
 377 +#include "qmp-commands.h"
 378 +#include "qemu-options.h"
 379 +#include "migration/qemu-file.h"
 380 +#include "qom/qom-qobject.h"
 381 +#include "migration/migration.h"
 382 +#include "block/snapshot.h"
 383 +#include "block/qapi.h"
 384 +#include "block/block.h"
 385 +#include "qemu/timer.h"
 386 +
 387 +/* #define DEBUG_SAVEVM_STATE */
 388 +
 389 +#ifdef DEBUG_SAVEVM_STATE
 390 +#define DPRINTF(fmt, ...) \
 391 +    do { printf("savevm-async: " fmt, ## __VA_ARGS__); } while (0)
 392 +#else
 393 +#define DPRINTF(fmt, ...) \
 394 +    do { } while (0)
 395 +#endif
 396 +
 397 +enum {
 398 +    SAVE_STATE_DONE,
 399 +    SAVE_STATE_ERROR,
 400 +    SAVE_STATE_ACTIVE,
 401 +    SAVE_STATE_COMPLETED,
 402 +};
 403 +
 404 +
 405 +static struct SnapshotState {
 406 +    BlockDriverState *bs;
 407 +    size_t bs_pos;
 408 +    int state;
 409 +    Error *error;
 410 +    int saved_vm_running;
 411 +    QEMUFile *file;
 412 +    int64_t total_time;
 413 +} snap_state;
 414 +
 415 +SaveVMInfo *qmp_query_savevm(Error **errp)
 416 +{
 417 +    SaveVMInfo *info = g_malloc0(sizeof(*info));
 418 +    struct SnapshotState *s = &snap_state;
 419 +
 420 +    if (s->state != SAVE_STATE_DONE) {
 421 +        info->has_bytes = true;
 422 +        info->bytes = s->bs_pos;
 423 +        switch (s->state) {
 424 +        case SAVE_STATE_ERROR:
 425 +            info->has_status = true;
 426 +            info->status = g_strdup("failed");
 427 +            info->has_total_time = true;
 428 +            info->total_time = s->total_time;
 429 +            if (s->error) {
 430 +                info->has_error = true;
 431 +                info->error = g_strdup(error_get_pretty(s->error));
 432 +            }
 433 +            break;
 434 +        case SAVE_STATE_ACTIVE:
 435 +            info->has_status = true;
 436 +            info->status = g_strdup("active");
 437 +            info->has_total_time = true;
 438 +            info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME)
 439 +                - s->total_time;
 440 +            break;
 441 +        case SAVE_STATE_COMPLETED:
 442 +            info->has_status = true;
 443 +            info->status = g_strdup("completed");
 444 +            info->has_total_time = true;
 445 +            info->total_time = s->total_time;
 446 +            break;
 447 +        }
 448 +    }
 449 +
 450 +    return info;
 451 +}
 452 +
 453 +static int save_snapshot_cleanup(void)
 454 +{
 455 +    int ret = 0;
 456 +
 457 +    DPRINTF("save_snapshot_cleanup\n");
 458 +
 459 +    snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) -
 460 +        snap_state.total_time;
 461 +
 462 +    if (snap_state.file) {
 463 +        ret = qemu_fclose(snap_state.file);
 464 +    }
 465 +
 466 +    if (snap_state.bs) {
 467 +        /* try to truncate, but ignore errors (will fail on block devices).
 468 +         * note: bdrv_read() need whole blocks, so we round up
 469 +         */
 470 +        size_t size = (snap_state.bs_pos + BDRV_SECTOR_SIZE) & BDRV_SECTOR_MASK;
 471 +        bdrv_truncate(snap_state.bs, size);
 472 +        bdrv_set_in_use(snap_state.bs, 0);
 473 +        bdrv_unref(snap_state.bs);
 474 +        snap_state.bs = NULL;
 475 +    }
 476 +
 477 +    return ret;
 478 +}
 479 +
 480 +static void save_snapshot_error(const char *fmt, ...)
 481 +{
 482 +    va_list ap;
 483 +    char *msg;
 484 +
 485 +    va_start(ap, fmt);
 486 +    msg = g_strdup_vprintf(fmt, ap);
 487 +    va_end(ap);
 488 +
 489 +    DPRINTF("save_snapshot_error: %s\n", msg);
 490 +
 491 +    if (!snap_state.error) {
 492 +        error_set(&snap_state.error, ERROR_CLASS_GENERIC_ERROR, "%s", msg);
 493 +    }
 494 +
 495 +    g_free (msg);
 496 +
 497 +    snap_state.state = SAVE_STATE_ERROR;
 498 +
 499 +    save_snapshot_cleanup();
 500 +}
 501 +
 502 +static void save_snapshot_completed(void)
 503 +{
 504 +    DPRINTF("save_snapshot_completed\n");
 505 +
 506 +    if (save_snapshot_cleanup() < 0) {
 507 +        snap_state.state = SAVE_STATE_ERROR;
 508 +    } else {
 509 +        snap_state.state = SAVE_STATE_COMPLETED;
 510 +    }
 511 +}
 512 +
 513 +static int block_state_close(void *opaque)
 514 +{
 515 +    snap_state.file = NULL;
 516 +    return bdrv_flush(snap_state.bs);
 517 +}
 518 +
 519 +static int block_state_put_buffer(void *opaque, const uint8_t *buf,
 520 +                                  int64_t pos, int size)
 521 +{
 522 +    int ret;
 523 +
 524 +    assert(pos == snap_state.bs_pos);
 525 +
 526 +    if ((ret = bdrv_pwrite(snap_state.bs, snap_state.bs_pos, buf, size)) > 0) {
 527 +        snap_state.bs_pos += ret;
 528 +    }
 529 +
 530 +    return ret;
 531 +}
 532 +
 533 +static void process_savevm_co(void *opaque)
 534 +{
 535 +    int ret;
 536 +    int64_t maxlen;
 537 +    MigrationParams params = {
 538 +        .blk = 0,
 539 +        .shared = 0
 540 +    };
 541 +
 542 +    snap_state.state = SAVE_STATE_ACTIVE;
 543 +
 544 +    qemu_mutex_unlock_iothread();
 545 +    ret = qemu_savevm_state_begin(snap_state.file, &params);
 546 +    qemu_mutex_lock_iothread();
 547 +
 548 +    if (ret < 0) {
 549 +        save_snapshot_error("qemu_savevm_state_begin failed");
 550 +        return;
 551 +    }
 552 +
 553 +    while (snap_state.state == SAVE_STATE_ACTIVE) {
 554 +        uint64_t pending_size;
 555 +
 556 +        pending_size = qemu_savevm_state_pending(snap_state.file, 0);
 557 +
 558 +        if (pending_size) {
 559 +                ret = qemu_savevm_state_iterate(snap_state.file);
 560 +                if (ret < 0) {
 561 +                    save_snapshot_error("qemu_savevm_state_iterate error %d", ret);
 562 +                    break;
 563 +                }
 564 +                DPRINTF("savevm inerate pending size %lu ret %d\n", pending_size, ret);
 565 +        } else {
 566 +            DPRINTF("done iterating\n");
 567 +            if (runstate_is_running()) {
 568 +                vm_stop(RUN_STATE_SAVE_VM);
 569 +            }
 570 +            DPRINTF("savevm inerate finished\n");
 571 +            qemu_savevm_state_complete(snap_state.file);
 572 +            DPRINTF("save complete\n");
 573 +            save_snapshot_completed();
 574 +            break;
 575 +        }
 576 +
 577 +        /* stop the VM if we get to the end of available space,
 578 +         * or if pending_size is just a few MB
 579 +         */
 580 +        maxlen = bdrv_getlength(snap_state.bs) - 30*1024*1024;
 581 +        if ((pending_size < 100000) ||
 582 +            ((snap_state.bs_pos + pending_size) >= maxlen)) {
 583 +            if (runstate_is_running()) {
 584 +                vm_stop(RUN_STATE_SAVE_VM);
 585 +            }
 586 +        }
 587 +    }
 588 +}
 589 +
 590 +static const QEMUFileOps block_file_ops = {
 591 +    .put_buffer =     block_state_put_buffer,
 592 +    .close =          block_state_close,
 593 +};
 594 +
 595 +
 596 +void qmp_savevm_start(bool has_statefile, const char *statefile, Error **errp)
 597 +{
 598 +    BlockDriver *drv = NULL;
 599 +    Error *local_err = NULL;
 600 +
 601 +    int bdrv_oflags = BDRV_O_CACHE_WB | BDRV_O_RDWR;
 602 +    int ret;
 603 +
 604 +    if (snap_state.state != SAVE_STATE_DONE) {
 605 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 606 +                  "VM snapshot already started\n");
 607 +        return;
 608 +    }
 609 +
 610 +    /* initialize snapshot info */
 611 +    snap_state.saved_vm_running = runstate_is_running();
 612 +    snap_state.bs_pos = 0;
 613 +    snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 614 +
 615 +    if (snap_state.error) {
 616 +        error_free(snap_state.error);
 617 +        snap_state.error = NULL;
 618 +    }
 619 +
 620 +    if (!has_statefile) {
 621 +        vm_stop(RUN_STATE_SAVE_VM);
 622 +        snap_state.state = SAVE_STATE_COMPLETED;
 623 +        return;
 624 +    }
 625 +
 626 +    if (qemu_savevm_state_blocked(errp)) {
 627 +        return;
 628 +    }
 629 +
 630 +    /* Open the image */
 631 +    snap_state.bs = bdrv_new("vmstate");
 632 +    ret = bdrv_open(&snap_state.bs, statefile, NULL, NULL, bdrv_oflags, drv, &local_err);
 633 +
 634 +    if (ret < 0) {
 635 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR, "failed to open '%s'", statefile);
 636 +        goto restart;
 637 +    }
 638 +
 639 +    snap_state.file = qemu_fopen_ops(&snap_state, &block_file_ops);
 640 +
 641 +    if (!snap_state.file) {
 642 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR, "failed to open '%s'", statefile);
 643 +        goto restart;
 644 +    }
 645 +
 646 +
 647 +    bdrv_set_in_use(snap_state.bs, 1);
 648 +    bdrv_ref(snap_state.bs);
 649 +
 650 +    Coroutine *co = qemu_coroutine_create(process_savevm_co);
 651 +    qemu_coroutine_enter(co, NULL);
 652 +
 653 +    return;
 654 +
 655 +restart:
 656 +
 657 +    save_snapshot_error("setup failed");
 658 +
 659 +    if (snap_state.saved_vm_running) {
 660 +        vm_start();
 661 +    }
 662 +}
 663 +
 664 +void qmp_savevm_end(Error **errp)
 665 +{
 666 +    if (snap_state.state == SAVE_STATE_DONE) {
 667 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 668 +                  "VM snapshot not started\n");
 669 +        return;
 670 +    }
 671 +
 672 +    if (snap_state.saved_vm_running) {
 673 +        vm_start();
 674 +    }
 675 +
 676 +    snap_state.state = SAVE_STATE_DONE;
 677 +}
 678 +
 679 +void qmp_snapshot_drive(const char *device, const char *name, Error **errp)
 680 +{
 681 +    BlockDriverState *bs;
 682 +    QEMUSnapshotInfo sn1, *sn = &sn1;
 683 +    int ret;
 684 +#ifdef _WIN32
 685 +    struct _timeb tb;
 686 +#else
 687 +    struct timeval tv;
 688 +#endif
 689 +
 690 +    if (snap_state.state != SAVE_STATE_COMPLETED) {
 691 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 692 +                  "VM snapshot not ready/started\n");
 693 +        return;
 694 +    }
 695 +
 696 +    bs = bdrv_find(device);
 697 +    if (!bs) {
 698 +        error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 699 +        return;
 700 +    }
 701 +
 702 +    if (!bdrv_is_inserted(bs)) {
 703 +        error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
 704 +        return;
 705 +    }
 706 +
 707 +    if (bdrv_is_read_only(bs)) {
 708 +        error_set(errp, QERR_DEVICE_IS_READ_ONLY, device);
 709 +        return;
 710 +    }
 711 +
 712 +    if (!bdrv_can_snapshot(bs)) {
 713 +        error_set(errp, QERR_NOT_SUPPORTED);
 714 +        return;
 715 +    }
 716 +
 717 +    if (bdrv_snapshot_find(bs, sn, name) >= 0) {
 718 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 719 +                  "snapshot '%s' already exists", name);
 720 +        return;
 721 +    }
 722 +
 723 +    sn = &sn1;
 724 +    memset(sn, 0, sizeof(*sn));
 725 +
 726 +#ifdef _WIN32
 727 +    _ftime(&tb);
 728 +    sn->date_sec = tb.time;
 729 +    sn->date_nsec = tb.millitm * 1000000;
 730 +#else
 731 +    gettimeofday(&tv, NULL);
 732 +    sn->date_sec = tv.tv_sec;
 733 +    sn->date_nsec = tv.tv_usec * 1000;
 734 +#endif
 735 +    sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 736 +
 737 +    pstrcpy(sn->name, sizeof(sn->name), name);
 738 +
 739 +    sn->vm_state_size = 0; /* do not save state */
 740 +
 741 +    ret = bdrv_snapshot_create(bs, sn);
 742 +    if (ret < 0) {
 743 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 744 +                  "Error while creating snapshot on '%s'\n", device);
 745 +        return;
 746 +    }
 747 +}
 748 +
 749 +void qmp_delete_drive_snapshot(const char *device, const char *name,
 750 +                               Error **errp)
 751 +{
 752 +    BlockDriverState *bs;
 753 +    QEMUSnapshotInfo sn1, *sn = &sn1;
 754 +    Error *local_err = NULL;
 755 +
 756 +    int ret;
 757 +
 758 +    bs = bdrv_find(device);
 759 +    if (!bs) {
 760 +        error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 761 +        return;
 762 +    }
 763 +    if (bdrv_is_read_only(bs)) {
 764 +        error_set(errp, QERR_DEVICE_IS_READ_ONLY, device);
 765 +        return;
 766 +    }
 767 +
 768 +    if (!bdrv_can_snapshot(bs)) {
 769 +        error_set(errp, QERR_NOT_SUPPORTED);
 770 +        return;
 771 +    }
 772 +
 773 +    if (bdrv_snapshot_find(bs, sn, name) < 0) {
 774 +        /* return success if snapshot does not exists */
 775 +        return;
 776 +    }
 777 +
 778 +    ret = bdrv_snapshot_delete(bs, NULL, name, &local_err);
 779 +    if (ret < 0) {
 780 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 781 +                  "Error while deleting snapshot on '%s'\n", device);
 782 +        return;
 783 +    }
 784 +}
 785 +
 786 +static int loadstate_get_buffer(void *opaque, uint8_t *buf, int64_t pos,
 787 +                                int size)
 788 +{
 789 +    BlockDriverState *bs = (BlockDriverState *)opaque;
 790 +    int64_t maxlen = bdrv_getlength(bs);
 791 +    if (pos > maxlen) {
 792 +        return -EIO;
 793 +    }
 794 +    if ((pos + size) > maxlen) {
 795 +        size = maxlen - pos - 1;
 796 +    }
 797 +    if (size == 0) {
 798 +        return 0;
 799 +    }
 800 +    return bdrv_pread(bs, pos, buf, size);
 801 +}
 802 +
 803 +static const QEMUFileOps loadstate_file_ops = {
 804 +    .get_buffer = loadstate_get_buffer,
 805 +};
 806 +
 807 +int load_state_from_blockdev(const char *filename)
 808 +{
 809 +    BlockDriverState *bs = NULL;
 810 +    BlockDriver *drv = NULL;
 811 +    Error *local_err = NULL;
 812 +
 813 +    QEMUFile *f;
 814 +    int ret = -1;
 815 +
 816 +    bs = bdrv_new("vmstate");
 817 +    ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_CACHE_WB, drv, &local_err);
 818 +    bdrv_set_in_use(bs, 1);
 819 +    bdrv_ref(bs);
 820 +
 821 +    if (ret < 0) {
 822 +        error_report("Could not open VM state file");
 823 +        goto the_end;
 824 +    }
 825 +
 826 +    /* restore the VM state */
 827 +    f = qemu_fopen_ops(bs, &loadstate_file_ops);
 828 +    if (!f) {
 829 +        error_report("Could not open VM state file");
 830 +        ret = -EINVAL;
 831 +        goto the_end;
 832 +    }
 833 +
 834 +    qemu_system_reset(VMRESET_SILENT);
 835 +    ret = qemu_loadvm_state(f);
 836 +
 837 +    qemu_fclose(f);
 838 +    if (ret < 0) {
 839 +        error_report("Error %d while loading VM state", ret);
 840 +        goto the_end;
 841 +    }
 842 +
 843 +    ret = 0;
 844 +
 845 + the_end:
 846 +    if (bs) {
 847 +        bdrv_set_in_use(bs, 0);
 848 +        bdrv_unref(bs);
 849 +    }
 850 +    return ret;
 851 +}
 852 Index: new/savevm.c
 853 ===================================================================
 854 --- new.orig/savevm.c   2014-05-05 09:49:29.000000000 +0200
 855 +++ new/savevm.c        2014-05-05 09:54:17.000000000 +0200
 856 @@ -460,11 +460,11 @@
 857      return false;
 858  }
 859
 860 -void qemu_savevm_state_begin(QEMUFile *f,
 861 +int qemu_savevm_state_begin(QEMUFile *f,
 862                               const MigrationParams *params)
 863  {
 864      SaveStateEntry *se;
 865 -    int ret;
 866 +    int ret = 0;
 867
 868      trace_savevm_state_begin();
 869      QTAILQ_FOREACH(se, &savevm_handlers, entry) {
 870 @@ -506,6 +506,7 @@
 871              break;
 872          }
 873      }
 874 +    return ret;
 875  }
 876
 877  /*
 878 @@ -554,7 +555,7 @@
 879      return ret;
 880  }
 881
 882 -void qemu_savevm_state_complete(QEMUFile *f)
 883 +int qemu_savevm_state_complete(QEMUFile *f)
 884  {
 885      SaveStateEntry *se;
 886      int ret;
 887 @@ -581,7 +582,7 @@
 888          trace_savevm_section_end(se->idstr, se->section_id);
 889          if (ret < 0) {
 890              qemu_file_set_error(f, ret);
 891 -            return;
 892 +            return ret;
 893          }
 894      }
 895
 896 @@ -610,6 +611,7 @@
 897
 898      qemu_put_byte(f, QEMU_VM_EOF);
 899      qemu_fflush(f);
 900 +    return qemu_file_get_error(f);
 901  }
 902
 903  uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size)
 904 Index: new/vl.c
 905 ===================================================================
 906 --- new.orig/vl.c       2014-05-05 09:49:29.000000000 +0200
 907 +++ new/vl.c    2014-05-05 09:54:17.000000000 +0200
 908 @@ -2953,6 +2953,7 @@
 909      int optind;
 910      const char *optarg;
 911      const char *loadvm = NULL;
 912 +    const char *loadstate = NULL;
 913      MachineClass *machine_class;
 914      QEMUMachine *machine;
 915      const char *cpu_model;
 916 @@ -3574,6 +3575,9 @@
 917             case QEMU_OPTION_loadvm:
 918                 loadvm = optarg;
 919                 break;
 920 +            case QEMU_OPTION_loadstate:
 921 +                loadstate = optarg;
 922 +                break;
 923              case QEMU_OPTION_full_screen:
 924                  full_screen = 1;
 925                  break;
 926 @@ -4541,6 +4545,10 @@
 927          if (load_vmstate(loadvm) < 0) {
 928              autostart = 0;
 929          }
 930 +    } else if (loadstate) {
 931 +        if (load_state_from_blockdev(loadstate) < 0) {
 932 +            autostart = 0;
 933 +        }
 934      }
 935
 936      if (incoming) {