debian/patches/pve/0010-internal-snapshot-async.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Wolfgang Bumiller <w.bumiller@proxmox.com>
   3 Date: Wed, 9 Dec 2015 16:04:32 +0100
   4 Subject: [PATCH] internal snapshot async
   5
   6 ---
   7  Makefile.objs                |   2 +-
   8  hmp-commands-info.hx         |  13 ++
   9  hmp-commands.hx              |  32 +++
  10  hmp.c                        |  57 +++++
  11  hmp.h                        |   5 +
  12  include/migration/snapshot.h |   1 +
  13  qapi-schema.json             |  32 +++
  14  qapi/migration.json          |  34 +++
  15  qemu-options.hx              |  13 ++
  16  savevm-async.c               | 524 +++++++++++++++++++++++++++++++++++++++++++
  17  vl.c                         |  10 +
  18  11 files changed, 722 insertions(+), 1 deletion(-)
  19  create mode 100644 savevm-async.c
  20
  21 diff --git a/Makefile.objs b/Makefile.objs
  22 index 285c6f3c15..686247b556 100644
  23 --- a/Makefile.objs
  24 +++ b/Makefile.objs
  25 @@ -41,6 +41,7 @@ io-obj-y = io/
  26  ifeq ($(CONFIG_SOFTMMU),y)
  27  common-obj-y = blockdev.o blockdev-nbd.o block/
  28  common-obj-y += bootdevice.o iothread.o
  29 +common-obj-y += savevm-async.o
  30  common-obj-y += net/
  31  common-obj-y += qdev-monitor.o device-hotplug.o
  32  common-obj-$(CONFIG_WIN32) += os-win32.o
  33 @@ -49,7 +50,6 @@ common-obj-$(CONFIG_POSIX) += os-posix.o
  34  common-obj-$(CONFIG_LINUX) += fsdev/
  35
  36  common-obj-y += migration/
  37 -
  38  common-obj-y += audio/
  39  common-obj-y += hw/
  40
  41 diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx
  42 index 54c3e5eac6..3bf69a193c 100644
  43 --- a/hmp-commands-info.hx
  44 +++ b/hmp-commands-info.hx
  45 @@ -566,6 +566,19 @@ Show current migration xbzrle cache size.
  46  ETEXI
  47
  48      {
  49 +        .name       = "savevm",
  50 +        .args_type  = "",
  51 +        .params     = "",
  52 +        .help       = "show savevm status",
  53 +        .cmd = hmp_info_savevm,
  54 +    },
  55 +
  56 +STEXI
  57 +@item info savevm
  58 +show savevm status
  59 +ETEXI
  60 +
  61 +    {
  62          .name       = "balloon",
  63          .args_type  = "",
  64          .params     = "",
  65 diff --git a/hmp-commands.hx b/hmp-commands.hx
  66 index 4afd57cf5f..b35bc6ab6c 100644
  67 --- a/hmp-commands.hx
  68 +++ b/hmp-commands.hx
  69 @@ -1873,3 +1873,35 @@ ETEXI
  70  STEXI
  71  @end table
  72  ETEXI
  73 +
  74 +    {
  75 +        .name       = "savevm-start",
  76 +        .args_type  = "statefile:s?",
  77 +        .params     = "[statefile]",
  78 +        .help       = "Prepare for snapshot and halt VM. Save VM state to statefile.",
  79 +        .cmd = hmp_savevm_start,
  80 +    },
  81 +
  82 +    {
  83 +        .name       = "snapshot-drive",
  84 +        .args_type  = "device:s,name:s",
  85 +        .params     = "device name",
  86 +        .help       = "Create internal snapshot.",
  87 +        .cmd = hmp_snapshot_drive,
  88 +    },
  89 +
  90 +    {
  91 +        .name       = "delete-drive-snapshot",
  92 +        .args_type  = "device:s,name:s",
  93 +        .params     = "device name",
  94 +        .help       = "Delete internal snapshot.",
  95 +        .cmd = hmp_delete_drive_snapshot,
  96 +    },
  97 +
  98 +    {
  99 +        .name       = "savevm-end",
 100 +        .args_type  = "",
 101 +        .params     = "",
 102 +        .help       = "Resume VM after snaphot.",
 103 +        .cmd = hmp_savevm_end,
 104 +    },
 105 diff --git a/hmp.c b/hmp.c
 106 index 4e1d571003..b9ade681f0 100644
 107 --- a/hmp.c
 108 +++ b/hmp.c
 109 @@ -2486,6 +2486,63 @@ void hmp_info_memory_devices(Monitor *mon, const QDict *qdict)
 110      hmp_handle_error(mon, &err);
 111  }
 112
 113 +void hmp_savevm_start(Monitor *mon, const QDict *qdict)
 114 +{
 115 +    Error *errp = NULL;
 116 +    const char *statefile = qdict_get_try_str(qdict, "statefile");
 117 +
 118 +    qmp_savevm_start(statefile != NULL, statefile, &errp);
 119 +    hmp_handle_error(mon, &errp);
 120 +}
 121 +
 122 +void hmp_snapshot_drive(Monitor *mon, const QDict *qdict)
 123 +{
 124 +    Error *errp = NULL;
 125 +    const char *name = qdict_get_str(qdict, "name");
 126 +    const char *device = qdict_get_str(qdict, "device");
 127 +
 128 +    qmp_snapshot_drive(device, name, &errp);
 129 +    hmp_handle_error(mon, &errp);
 130 +}
 131 +
 132 +void hmp_delete_drive_snapshot(Monitor *mon, const QDict *qdict)
 133 +{
 134 +    Error *errp = NULL;
 135 +    const char *name = qdict_get_str(qdict, "name");
 136 +    const char *device = qdict_get_str(qdict, "device");
 137 +
 138 +    qmp_delete_drive_snapshot(device, name, &errp);
 139 +    hmp_handle_error(mon, &errp);
 140 +}
 141 +
 142 +void hmp_savevm_end(Monitor *mon, const QDict *qdict)
 143 +{
 144 +    Error *errp = NULL;
 145 +
 146 +    qmp_savevm_end(&errp);
 147 +    hmp_handle_error(mon, &errp);
 148 +}
 149 +
 150 +void hmp_info_savevm(Monitor *mon, const QDict *qdict)
 151 +{
 152 +    SaveVMInfo *info;
 153 +    info = qmp_query_savevm(NULL);
 154 +
 155 +    if (info->has_status) {
 156 +        monitor_printf(mon, "savevm status: %s\n", info->status);
 157 +        monitor_printf(mon, "total time: %" PRIu64 " milliseconds\n",
 158 +                       info->total_time);
 159 +    } else {
 160 +        monitor_printf(mon, "savevm status: not running\n");
 161 +    }
 162 +    if (info->has_bytes) {
 163 +        monitor_printf(mon, "Bytes saved: %"PRIu64"\n", info->bytes);
 164 +    }
 165 +    if (info->has_error) {
 166 +        monitor_printf(mon, "Error: %s\n", info->error);
 167 +    }
 168 +}
 169 +
 170  void hmp_info_iothreads(Monitor *mon, const QDict *qdict)
 171  {
 172      IOThreadInfoList *info_list = qmp_query_iothreads(NULL);
 173 diff --git a/hmp.h b/hmp.h
 174 index a6f56b1f29..45ada581b6 100644
 175 --- a/hmp.h
 176 +++ b/hmp.h
 177 @@ -26,6 +26,7 @@ void hmp_info_status(Monitor *mon, const QDict *qdict);
 178  void hmp_info_uuid(Monitor *mon, const QDict *qdict);
 179  void hmp_info_chardev(Monitor *mon, const QDict *qdict);
 180  void hmp_info_mice(Monitor *mon, const QDict *qdict);
 181 +void hmp_info_savevm(Monitor *mon, const QDict *qdict);
 182  void hmp_info_migrate(Monitor *mon, const QDict *qdict);
 183  void hmp_info_migrate_capabilities(Monitor *mon, const QDict *qdict);
 184  void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict);
 185 @@ -97,6 +98,10 @@ void hmp_netdev_add(Monitor *mon, const QDict *qdict);
 186  void hmp_netdev_del(Monitor *mon, const QDict *qdict);
 187  void hmp_getfd(Monitor *mon, const QDict *qdict);
 188  void hmp_closefd(Monitor *mon, const QDict *qdict);
 189 +void hmp_savevm_start(Monitor *mon, const QDict *qdict);
 190 +void hmp_snapshot_drive(Monitor *mon, const QDict *qdict);
 191 +void hmp_delete_drive_snapshot(Monitor *mon, const QDict *qdict);
 192 +void hmp_savevm_end(Monitor *mon, const QDict *qdict);
 193  void hmp_sendkey(Monitor *mon, const QDict *qdict);
 194  void hmp_screendump(Monitor *mon, const QDict *qdict);
 195  void hmp_nbd_server_start(Monitor *mon, const QDict *qdict);
 196 diff --git a/include/migration/snapshot.h b/include/migration/snapshot.h
 197 index c85b6ec75b..4411b7121d 100644
 198 --- a/include/migration/snapshot.h
 199 +++ b/include/migration/snapshot.h
 200 @@ -17,5 +17,6 @@
 201
 202  int save_snapshot(const char *name, Error **errp);
 203  int load_snapshot(const char *name, Error **errp);
 204 +int load_snapshot_from_blockdev(const char *filename, Error **errp);
 205
 206  #endif
 207 diff --git a/qapi-schema.json b/qapi-schema.json
 208 index 8f436ba1f3..348b527681 100644
 209 --- a/qapi-schema.json
 210 +++ b/qapi-schema.json
 211 @@ -2439,6 +2439,38 @@
 212  { 'command': 'query-target', 'returns': 'TargetInfo' }
 213
 214  ##
 215 +# @savevm-start:
 216 +#
 217 +# Prepare for snapshot and halt VM. Save VM state to statefile.
 218 +#
 219 +##
 220 +{ 'command': 'savevm-start', 'data': { '*statefile': 'str' } }
 221 +
 222 +##
 223 +# @snapshot-drive:
 224 +#
 225 +# Create an internal drive snapshot.
 226 +#
 227 +##
 228 +{ 'command': 'snapshot-drive', 'data': { 'device': 'str', 'name': 'str' } }
 229 +
 230 +##
 231 +# @delete-drive-snapshot:
 232 +#
 233 +# Delete a drive snapshot.
 234 +#
 235 +##
 236 +{ 'command': 'delete-drive-snapshot', 'data': { 'device': 'str', 'name': 'str' } }
 237 +
 238 +##
 239 +# @savevm-end:
 240 +#
 241 +# Resume VM after a snapshot.
 242 +#
 243 +##
 244 +{ 'command': 'savevm-end' }
 245 +
 246 +##
 247  # @AcpiTableOptions:
 248  #
 249  # Specify an ACPI table on the command line to load.
 250 diff --git a/qapi/migration.json b/qapi/migration.json
 251 index 03f57c9616..9ae55b81a2 100644
 252 --- a/qapi/migration.json
 253 +++ b/qapi/migration.json
 254 @@ -170,6 +170,40 @@
 255             '*error-desc': 'str'} }
 256
 257  ##
 258 +# @SaveVMInfo:
 259 +#
 260 +# Information about current migration process.
 261 +#
 262 +# @status: string describing the current savevm status.
 263 +#          This can be 'active', 'completed', 'failed'.
 264 +#          If this field is not returned, no savevm process
 265 +#          has been initiated
 266 +#
 267 +# @error: string containing error message is status is failed.
 268 +#
 269 +# @total-time: total amount of milliseconds since savevm started.
 270 +#        If savevm has ended, it returns the total save time
 271 +#
 272 +# @bytes: total amount of data transfered
 273 +#
 274 +# Since: 1.3
 275 +##
 276 +{ 'struct': 'SaveVMInfo',
 277 +  'data': {'*status': 'str', '*error': 'str',
 278 +           '*total-time': 'int', '*bytes': 'int'} }
 279 +
 280 +##
 281 +# @query-savevm:
 282 +#
 283 +# Returns information about current savevm process.
 284 +#
 285 +# Returns: @SaveVMInfo
 286 +#
 287 +# Since: 1.3
 288 +##
 289 +{ 'command': 'query-savevm', 'returns': 'SaveVMInfo' }
 290 +
 291 +##
 292  # @query-migrate:
 293  #
 294  # Returns information about current migration process. If migration
 295 diff --git a/qemu-options.hx b/qemu-options.hx
 296 index 57f2c6a75f..7c054af8f9 100644
 297 --- a/qemu-options.hx
 298 +++ b/qemu-options.hx
 299 @@ -3698,6 +3698,19 @@ STEXI
 300  Start right away with a saved state (@code{loadvm} in monitor)
 301  ETEXI
 302
 303 +DEF("loadstate", HAS_ARG, QEMU_OPTION_loadstate, \
 304 +    "-loadstate file\n" \
 305 +    "                start right away with a saved state\n",
 306 +    QEMU_ARCH_ALL)
 307 +STEXI
 308 +@item -loadstate @var{file}
 309 +@findex -loadstate
 310 +Start right away with a saved state. This option does not rollback
 311 +disk state like @code{loadvm}, so user must make sure that disk
 312 +have correct state. @var{file} can be any valid device URL. See the section
 313 +for "Device URL Syntax" for more information.
 314 +ETEXI
 315 +
 316  #ifndef _WIN32
 317  DEF("daemonize", 0, QEMU_OPTION_daemonize, \
 318      "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
 319 diff --git a/savevm-async.c b/savevm-async.c
 320 new file mode 100644
 321 index 0000000000..897134ab5a
 322 --- /dev/null
 323 +++ b/savevm-async.c
 324 @@ -0,0 +1,524 @@
 325 +#include "qemu/osdep.h"
 326 +#include "migration/migration.h"
 327 +#include "migration/savevm.h"
 328 +#include "migration/snapshot.h"
 329 +#include "migration/global_state.h"
 330 +#include "migration/ram.h"
 331 +#include "migration/qemu-file.h"
 332 +#include "qapi/qmp/qerror.h"
 333 +#include "sysemu/sysemu.h"
 334 +#include "qmp-commands.h"
 335 +#include "block/block.h"
 336 +#include "sysemu/block-backend.h"
 337 +#include "qapi/qmp/qstring.h"
 338 +#include "qemu/cutils.h"
 339 +
 340 +/* #define DEBUG_SAVEVM_STATE */
 341 +
 342 +#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
 343 +
 344 +#ifdef DEBUG_SAVEVM_STATE
 345 +#define DPRINTF(fmt, ...) \
 346 +    do { printf("savevm-async: " fmt, ## __VA_ARGS__); } while (0)
 347 +#else
 348 +#define DPRINTF(fmt, ...) \
 349 +    do { } while (0)
 350 +#endif
 351 +
 352 +enum {
 353 +    SAVE_STATE_DONE,
 354 +    SAVE_STATE_ERROR,
 355 +    SAVE_STATE_ACTIVE,
 356 +    SAVE_STATE_COMPLETED,
 357 +    SAVE_STATE_CANCELLED
 358 +};
 359 +
 360 +
 361 +static struct SnapshotState {
 362 +    BlockBackend *target;
 363 +    size_t bs_pos;
 364 +    int state;
 365 +    Error *error;
 366 +    Error *blocker;
 367 +    int saved_vm_running;
 368 +    QEMUFile *file;
 369 +    int64_t total_time;
 370 +} snap_state;
 371 +
 372 +SaveVMInfo *qmp_query_savevm(Error **errp)
 373 +{
 374 +    SaveVMInfo *info = g_malloc0(sizeof(*info));
 375 +    struct SnapshotState *s = &snap_state;
 376 +
 377 +    if (s->state != SAVE_STATE_DONE) {
 378 +        info->has_bytes = true;
 379 +        info->bytes = s->bs_pos;
 380 +        switch (s->state) {
 381 +        case SAVE_STATE_ERROR:
 382 +            info->has_status = true;
 383 +            info->status = g_strdup("failed");
 384 +            info->has_total_time = true;
 385 +            info->total_time = s->total_time;
 386 +            if (s->error) {
 387 +                info->has_error = true;
 388 +                info->error = g_strdup(error_get_pretty(s->error));
 389 +            }
 390 +            break;
 391 +        case SAVE_STATE_ACTIVE:
 392 +            info->has_status = true;
 393 +            info->status = g_strdup("active");
 394 +            info->has_total_time = true;
 395 +            info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME)
 396 +                - s->total_time;
 397 +            break;
 398 +        case SAVE_STATE_COMPLETED:
 399 +            info->has_status = true;
 400 +            info->status = g_strdup("completed");
 401 +            info->has_total_time = true;
 402 +            info->total_time = s->total_time;
 403 +            break;
 404 +        }
 405 +    }
 406 +
 407 +    return info;
 408 +}
 409 +
 410 +static int save_snapshot_cleanup(void)
 411 +{
 412 +    int ret = 0;
 413 +
 414 +    DPRINTF("save_snapshot_cleanup\n");
 415 +
 416 +    snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) -
 417 +        snap_state.total_time;
 418 +
 419 +    if (snap_state.file) {
 420 +        ret = qemu_fclose(snap_state.file);
 421 +    }
 422 +
 423 +    if (snap_state.target) {
 424 +        /* try to truncate, but ignore errors (will fail on block devices).
 425 +         * note: bdrv_read() need whole blocks, so we round up
 426 +         */
 427 +        size_t size = (snap_state.bs_pos + BDRV_SECTOR_SIZE) & BDRV_SECTOR_MASK;
 428 +        blk_truncate(snap_state.target, size, PREALLOC_MODE_OFF, NULL);
 429 +        blk_op_unblock_all(snap_state.target, snap_state.blocker);
 430 +        error_free(snap_state.blocker);
 431 +        snap_state.blocker = NULL;
 432 +        blk_unref(snap_state.target);
 433 +        snap_state.target = NULL;
 434 +    }
 435 +
 436 +    return ret;
 437 +}
 438 +
 439 +static void save_snapshot_error(const char *fmt, ...)
 440 +{
 441 +    va_list ap;
 442 +    char *msg;
 443 +
 444 +    va_start(ap, fmt);
 445 +    msg = g_strdup_vprintf(fmt, ap);
 446 +    va_end(ap);
 447 +
 448 +    DPRINTF("save_snapshot_error: %s\n", msg);
 449 +
 450 +    if (!snap_state.error) {
 451 +        error_set(&snap_state.error, ERROR_CLASS_GENERIC_ERROR, "%s", msg);
 452 +    }
 453 +
 454 +    g_free (msg);
 455 +
 456 +    snap_state.state = SAVE_STATE_ERROR;
 457 +
 458 +    save_snapshot_cleanup();
 459 +}
 460 +
 461 +static void save_snapshot_completed(void)
 462 +{
 463 +    DPRINTF("save_snapshot_completed\n");
 464 +
 465 +    if (save_snapshot_cleanup() < 0) {
 466 +        snap_state.state = SAVE_STATE_ERROR;
 467 +    } else {
 468 +        snap_state.state = SAVE_STATE_COMPLETED;
 469 +    }
 470 +}
 471 +
 472 +static int block_state_close(void *opaque)
 473 +{
 474 +    snap_state.file = NULL;
 475 +    return blk_flush(snap_state.target);
 476 +}
 477 +
 478 +static ssize_t block_state_writev_buffer(void *opaque, struct iovec *iov,
 479 +                                         int iovcnt, int64_t pos)
 480 +{
 481 +    int ret;
 482 +    QEMUIOVector qiov;
 483 +
 484 +    qemu_iovec_init_external(&qiov, iov, iovcnt);
 485 +    ret = blk_co_pwritev(snap_state.target, pos, qiov.size, &qiov, 0);
 486 +    if (ret < 0) {
 487 +        return ret;
 488 +    }
 489 +    snap_state.bs_pos += qiov.size;
 490 +    return qiov.size;
 491 +}
 492 +
 493 +static int store_and_stop(void) {
 494 +    if (global_state_store()) {
 495 +        save_snapshot_error("Error saving global state");
 496 +        return 1;
 497 +    }
 498 +    if (runstate_is_running()) {
 499 +        vm_stop(RUN_STATE_SAVE_VM);
 500 +    }
 501 +    return 0;
 502 +}
 503 +
 504 +static void process_savevm_co(void *opaque)
 505 +{
 506 +    int ret;
 507 +    int64_t maxlen;
 508 +
 509 +    snap_state.state = SAVE_STATE_ACTIVE;
 510 +
 511 +    qemu_mutex_unlock_iothread();
 512 +    qemu_savevm_state_header(snap_state.file);
 513 +    qemu_savevm_state_setup(snap_state.file);
 514 +    ret = qemu_file_get_error(snap_state.file);
 515 +    qemu_mutex_lock_iothread();
 516 +
 517 +    if (ret < 0) {
 518 +        save_snapshot_error("qemu_savevm_state_setup failed");
 519 +        return;
 520 +    }
 521 +
 522 +    while (snap_state.state == SAVE_STATE_ACTIVE) {
 523 +        uint64_t pending_size, pend_post, pend_nonpost;
 524 +
 525 +        qemu_savevm_state_pending(snap_state.file, 0, &pend_nonpost, &pend_post);
 526 +        pending_size = pend_post + pend_nonpost;
 527 +
 528 +        if (pending_size) {
 529 +                ret = qemu_savevm_state_iterate(snap_state.file, false);
 530 +                if (ret < 0) {
 531 +                    save_snapshot_error("qemu_savevm_state_iterate error %d", ret);
 532 +                    break;
 533 +                }
 534 +                DPRINTF("savevm inerate pending size %lu ret %d\n", pending_size, ret);
 535 +        } else {
 536 +            DPRINTF("done iterating\n");
 537 +            if (store_and_stop())
 538 +                break;
 539 +            DPRINTF("savevm inerate finished\n");
 540 +            /* upstream made the return value here inconsistent
 541 +             * (-1 instead of 'ret' in one case and 0 after flush which can
 542 +             * still set a file error...)
 543 +             */
 544 +            (void)qemu_savevm_state_complete_precopy(snap_state.file, false, false);
 545 +            ret = qemu_file_get_error(snap_state.file);
 546 +            if (ret < 0) {
 547 +                    save_snapshot_error("qemu_savevm_state_iterate error %d", ret);
 548 +                    break;
 549 +            }
 550 +            DPRINTF("save complete\n");
 551 +            save_snapshot_completed();
 552 +            break;
 553 +        }
 554 +
 555 +        /* stop the VM if we get to the end of available space,
 556 +         * or if pending_size is just a few MB
 557 +         */
 558 +        maxlen = blk_getlength(snap_state.target) - 30*1024*1024;
 559 +        if ((pending_size < 100000) ||
 560 +            ((snap_state.bs_pos + pending_size) >= maxlen)) {
 561 +            if (store_and_stop())
 562 +                break;
 563 +        }
 564 +    }
 565 +
 566 +    if(snap_state.state == SAVE_STATE_CANCELLED) {
 567 +        save_snapshot_completed();
 568 +        Error *errp = NULL;
 569 +        qmp_savevm_end(&errp);
 570 +    }
 571 +
 572 +}
 573 +
 574 +static const QEMUFileOps block_file_ops = {
 575 +    .writev_buffer =  block_state_writev_buffer,
 576 +    .close =          block_state_close,
 577 +};
 578 +
 579 +
 580 +void qmp_savevm_start(bool has_statefile, const char *statefile, Error **errp)
 581 +{
 582 +    Error *local_err = NULL;
 583 +
 584 +    int bdrv_oflags = BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_NO_FLUSH;
 585 +
 586 +    if (snap_state.state != SAVE_STATE_DONE) {
 587 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 588 +                  "VM snapshot already started\n");
 589 +        return;
 590 +    }
 591 +
 592 +    /* initialize snapshot info */
 593 +    snap_state.saved_vm_running = runstate_is_running();
 594 +    snap_state.bs_pos = 0;
 595 +    snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 596 +    snap_state.blocker = NULL;
 597 +
 598 +    if (snap_state.error) {
 599 +        error_free(snap_state.error);
 600 +        snap_state.error = NULL;
 601 +    }
 602 +
 603 +    if (!has_statefile) {
 604 +        vm_stop(RUN_STATE_SAVE_VM);
 605 +        snap_state.state = SAVE_STATE_COMPLETED;
 606 +        return;
 607 +    }
 608 +
 609 +    if (qemu_savevm_state_blocked(errp)) {
 610 +        return;
 611 +    }
 612 +
 613 +    /* Open the image */
 614 +    QDict *options = NULL;
 615 +    options = qdict_new();
 616 +    qdict_put(options, "driver", qstring_from_str("raw"));
 617 +    snap_state.target = blk_new_open(statefile, NULL, options, bdrv_oflags, &local_err);
 618 +    if (!snap_state.target) {
 619 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR, "failed to open '%s'", statefile);
 620 +        goto restart;
 621 +    }
 622 +
 623 +    snap_state.file = qemu_fopen_ops(&snap_state, &block_file_ops);
 624 +
 625 +    if (!snap_state.file) {
 626 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR, "failed to open '%s'", statefile);
 627 +        goto restart;
 628 +    }
 629 +
 630 +
 631 +    error_setg(&snap_state.blocker, "block device is in use by savevm");
 632 +    blk_op_block_all(snap_state.target, snap_state.blocker);
 633 +
 634 +    Coroutine *co = qemu_coroutine_create(process_savevm_co, NULL);
 635 +    qemu_coroutine_enter(co);
 636 +
 637 +    return;
 638 +
 639 +restart:
 640 +
 641 +    save_snapshot_error("setup failed");
 642 +
 643 +    if (snap_state.saved_vm_running) {
 644 +        vm_start();
 645 +    }
 646 +}
 647 +
 648 +void qmp_savevm_end(Error **errp)
 649 +{
 650 +    if (snap_state.state == SAVE_STATE_DONE) {
 651 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 652 +                  "VM snapshot not started\n");
 653 +        return;
 654 +    }
 655 +
 656 +    if (snap_state.state == SAVE_STATE_ACTIVE) {
 657 +        snap_state.state = SAVE_STATE_CANCELLED;
 658 +        return;
 659 +    }
 660 +
 661 +    if (snap_state.saved_vm_running) {
 662 +        vm_start();
 663 +    }
 664 +
 665 +    snap_state.state = SAVE_STATE_DONE;
 666 +}
 667 +
 668 +void qmp_snapshot_drive(const char *device, const char *name, Error **errp)
 669 +{
 670 +    BlockBackend *blk;
 671 +    BlockDriverState *bs;
 672 +    QEMUSnapshotInfo sn1, *sn = &sn1;
 673 +    int ret;
 674 +#ifdef _WIN32
 675 +    struct _timeb tb;
 676 +#else
 677 +    struct timeval tv;
 678 +#endif
 679 +
 680 +    if (snap_state.state != SAVE_STATE_COMPLETED) {
 681 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 682 +                  "VM snapshot not ready/started\n");
 683 +        return;
 684 +    }
 685 +
 686 +    blk = blk_by_name(device);
 687 +    if (!blk) {
 688 +        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
 689 +                  "Device '%s' not found", device);
 690 +        return;
 691 +    }
 692 +
 693 +    bs = blk_bs(blk);
 694 +    if (!bdrv_is_inserted(bs)) {
 695 +        error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
 696 +        return;
 697 +    }
 698 +
 699 +    if (bdrv_is_read_only(bs)) {
 700 +        error_setg(errp, "Node '%s' is read only", device);
 701 +        return;
 702 +    }
 703 +
 704 +    if (!bdrv_can_snapshot(bs)) {
 705 +        error_setg(errp, QERR_UNSUPPORTED);
 706 +        return;
 707 +    }
 708 +
 709 +    if (bdrv_snapshot_find(bs, sn, name) >= 0) {
 710 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 711 +                  "snapshot '%s' already exists", name);
 712 +        return;
 713 +    }
 714 +
 715 +    sn = &sn1;
 716 +    memset(sn, 0, sizeof(*sn));
 717 +
 718 +#ifdef _WIN32
 719 +    _ftime(&tb);
 720 +    sn->date_sec = tb.time;
 721 +    sn->date_nsec = tb.millitm * 1000000;
 722 +#else
 723 +    gettimeofday(&tv, NULL);
 724 +    sn->date_sec = tv.tv_sec;
 725 +    sn->date_nsec = tv.tv_usec * 1000;
 726 +#endif
 727 +    sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 728 +
 729 +    pstrcpy(sn->name, sizeof(sn->name), name);
 730 +
 731 +    sn->vm_state_size = 0; /* do not save state */
 732 +
 733 +    ret = bdrv_snapshot_create(bs, sn);
 734 +    if (ret < 0) {
 735 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 736 +                  "Error while creating snapshot on '%s'\n", device);
 737 +        return;
 738 +    }
 739 +}
 740 +
 741 +void qmp_delete_drive_snapshot(const char *device, const char *name,
 742 +                               Error **errp)
 743 +{
 744 +    BlockBackend *blk;
 745 +    BlockDriverState *bs;
 746 +    QEMUSnapshotInfo sn1, *sn = &sn1;
 747 +    Error *local_err = NULL;
 748 +
 749 +    int ret;
 750 +
 751 +    blk = blk_by_name(device);
 752 +    if (!blk) {
 753 +        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
 754 +                  "Device '%s' not found", device);
 755 +        return;
 756 +    }
 757 +
 758 +    bs = blk_bs(blk);
 759 +    if (bdrv_is_read_only(bs)) {
 760 +        error_setg(errp, "Node '%s' is read only", device);
 761 +        return;
 762 +    }
 763 +
 764 +    if (!bdrv_can_snapshot(bs)) {
 765 +        error_setg(errp, QERR_UNSUPPORTED);
 766 +        return;
 767 +    }
 768 +
 769 +    if (bdrv_snapshot_find(bs, sn, name) < 0) {
 770 +        /* return success if snapshot does not exists */
 771 +        return;
 772 +    }
 773 +
 774 +    ret = bdrv_snapshot_delete(bs, NULL, name, &local_err);
 775 +    if (ret < 0) {
 776 +        error_set(errp, ERROR_CLASS_GENERIC_ERROR,
 777 +                  "Error while deleting snapshot on '%s'\n", device);
 778 +        return;
 779 +    }
 780 +}
 781 +
 782 +static ssize_t loadstate_get_buffer(void *opaque, uint8_t *buf, int64_t pos,
 783 +                                    size_t size)
 784 +{
 785 +    BlockBackend *be = opaque;
 786 +    int64_t maxlen = blk_getlength(be);
 787 +    if (pos > maxlen) {
 788 +        return -EIO;
 789 +    }
 790 +    if ((pos + size) > maxlen) {
 791 +        size = maxlen - pos - 1;
 792 +    }
 793 +    if (size == 0) {
 794 +        return 0;
 795 +    }
 796 +    return blk_pread(be, pos, buf, size);
 797 +}
 798 +
 799 +static const QEMUFileOps loadstate_file_ops = {
 800 +    .get_buffer = loadstate_get_buffer,
 801 +};
 802 +
 803 +int load_snapshot_from_blockdev(const char *filename, Error **errp)
 804 +{
 805 +    BlockBackend *be;
 806 +    Error *local_err = NULL;
 807 +    Error *blocker = NULL;
 808 +
 809 +    QEMUFile *f;
 810 +    int ret = -EINVAL;
 811 +
 812 +    be = blk_new_open(filename, NULL, NULL, 0, &local_err);
 813 +
 814 +    if (!be) {
 815 +        error_setg(errp, "Could not open VM state file");
 816 +        goto the_end;
 817 +    }
 818 +
 819 +    error_setg(&blocker, "block device is in use by load state");
 820 +    blk_op_block_all(be, blocker);
 821 +
 822 +    /* restore the VM state */
 823 +    f = qemu_fopen_ops(be, &loadstate_file_ops);
 824 +    if (!f) {
 825 +        error_setg(errp, "Could not open VM state file");
 826 +        goto the_end;
 827 +    }
 828 +
 829 +    qemu_system_reset(SHUTDOWN_CAUSE_NONE);
 830 +    ret = qemu_loadvm_state(f);
 831 +
 832 +    qemu_fclose(f);
 833 +    migration_incoming_state_destroy();
 834 +    if (ret < 0) {
 835 +        error_setg_errno(errp, -ret, "Error while loading VM state");
 836 +        goto the_end;
 837 +    }
 838 +
 839 +    ret = 0;
 840 +
 841 + the_end:
 842 +    if (be) {
 843 +        blk_op_unblock_all(be, blocker);
 844 +        error_free(blocker);
 845 +        blk_unref(be);
 846 +    }
 847 +    return ret;
 848 +}
 849 diff --git a/vl.c b/vl.c
 850 index 2e0fe15978..1bfbe95b22 100644
 851 --- a/vl.c
 852 +++ b/vl.c
 853 @@ -3109,6 +3109,7 @@ int main(int argc, char **argv, char **envp)
 854      int optind;
 855      const char *optarg;
 856      const char *loadvm = NULL;
 857 +    const char *loadstate = NULL;
 858      MachineClass *machine_class;
 859      const char *cpu_model;
 860      const char *vga_model = NULL;
 861 @@ -3785,6 +3786,9 @@ int main(int argc, char **argv, char **envp)
 862              case QEMU_OPTION_loadvm:
 863                  loadvm = optarg;
 864                  break;
 865 +            case QEMU_OPTION_loadstate:
 866 +                loadstate = optarg;
 867 +                break;
 868              case QEMU_OPTION_full_screen:
 869                  full_screen = 1;
 870                  break;
 871 @@ -4891,6 +4895,12 @@ int main(int argc, char **argv, char **envp)
 872              error_report_err(local_err);
 873              autostart = 0;
 874          }
 875 +    } else if (loadstate) {
 876 +        Error *local_err = NULL;
 877 +        if (load_snapshot_from_blockdev(loadstate, &local_err) < 0) {
 878 +            error_report_err(local_err);
 879 +            autostart = 0;
 880 +        }
 881      }
 882
 883      qdev_prop_check_globals();
 884 --
 885 2.11.0
 886