blockdev.c

   1 /*
   2  * QEMU host block devices
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or
   7  * later.  See the COPYING file in the top-level directory.
   8  */
   9
  10 #include "block.h"
  11 #include "blockdev.h"
  12 #include "monitor.h"
  13 #include "qerror.h"
  14 #include "qemu-option.h"
  15 #include "qemu-config.h"
  16 #include "sysemu.h"
  17 #include "hw/qdev.h"
  18 #include "block_int.h"
  19
  20 static QTAILQ_HEAD(drivelist, DriveInfo) drives = QTAILQ_HEAD_INITIALIZER(drives);
  21
  22 /*
  23  * We automatically delete the drive when a device using it gets
  24  * unplugged.  Questionable feature, but we can't just drop it.
  25  * Device models call blockdev_mark_auto_del() to schedule the
  26  * automatic deletion, and generic qdev code calls blockdev_auto_del()
  27  * when deletion is actually safe.
  28  */
  29 void blockdev_mark_auto_del(BlockDriverState *bs)
  30 {
  31     DriveInfo *dinfo = drive_get_by_blockdev(bs);
  32
  33     if (dinfo) {
  34         dinfo->auto_del = 1;
  35     }
  36 }
  37
  38 void blockdev_auto_del(BlockDriverState *bs)
  39 {
  40     DriveInfo *dinfo = drive_get_by_blockdev(bs);
  41
  42     if (dinfo && dinfo->auto_del) {
  43         drive_uninit(dinfo);
  44     }
  45 }
  46
  47 QemuOpts *drive_add(const char *file, const char *fmt, ...)
  48 {
  49     va_list ap;
  50     char optstr[1024];
  51     QemuOpts *opts;
  52
  53     va_start(ap, fmt);
  54     vsnprintf(optstr, sizeof(optstr), fmt, ap);
  55     va_end(ap);
  56
  57     opts = qemu_opts_parse(qemu_find_opts("drive"), optstr, 0);
  58     if (!opts) {
  59         return NULL;
  60     }
  61     if (file)
  62         qemu_opt_set(opts, "file", file);
  63     return opts;
  64 }
  65
  66 DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
  67 {
  68     DriveInfo *dinfo;
  69
  70     /* seek interface, bus and unit */
  71
  72     QTAILQ_FOREACH(dinfo, &drives, next) {
  73         if (dinfo->type == type &&
  74             dinfo->bus == bus &&
  75             dinfo->unit == unit)
  76             return dinfo;
  77     }
  78
  79     return NULL;
  80 }
  81
  82 int drive_get_max_bus(BlockInterfaceType type)
  83 {
  84     int max_bus;
  85     DriveInfo *dinfo;
  86
  87     max_bus = -1;
  88     QTAILQ_FOREACH(dinfo, &drives, next) {
  89         if(dinfo->type == type &&
  90            dinfo->bus > max_bus)
  91             max_bus = dinfo->bus;
  92     }
  93     return max_bus;
  94 }
  95
  96 DriveInfo *drive_get_by_blockdev(BlockDriverState *bs)
  97 {
  98     DriveInfo *dinfo;
  99
 100     QTAILQ_FOREACH(dinfo, &drives, next) {
 101         if (dinfo->bdrv == bs) {
 102             return dinfo;
 103         }
 104     }
 105     return NULL;
 106 }
 107
 108 static void bdrv_format_print(void *opaque, const char *name)
 109 {
 110     error_printf(" %s", name);
 111 }
 112
 113 void drive_uninit(DriveInfo *dinfo)
 114 {
 115     qemu_opts_del(dinfo->opts);
 116     bdrv_delete(dinfo->bdrv);
 117     QTAILQ_REMOVE(&drives, dinfo, next);
 118     qemu_free(dinfo);
 119 }
 120
 121 static int parse_block_error_action(const char *buf, int is_read)
 122 {
 123     if (!strcmp(buf, "ignore")) {
 124         return BLOCK_ERR_IGNORE;
 125     } else if (!is_read && !strcmp(buf, "enospc")) {
 126         return BLOCK_ERR_STOP_ENOSPC;
 127     } else if (!strcmp(buf, "stop")) {
 128         return BLOCK_ERR_STOP_ANY;
 129     } else if (!strcmp(buf, "report")) {
 130         return BLOCK_ERR_REPORT;
 131     } else {
 132         error_report("'%s' invalid %s error action",
 133                      buf, is_read ? "read" : "write");
 134         return -1;
 135     }
 136 }
 137
 138 DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error)
 139 {
 140     const char *buf;
 141     const char *file = NULL;
 142     char devname[128];
 143     const char *serial;
 144     const char *mediastr = "";
 145     BlockInterfaceType type;
 146     enum { MEDIA_DISK, MEDIA_CDROM } media;
 147     int bus_id, unit_id;
 148     int cyls, heads, secs, translation;
 149     BlockDriver *drv = NULL;
 150     int max_devs;
 151     int index;
 152     int ro = 0;
 153     int bdrv_flags = 0;
 154     int on_read_error, on_write_error;
 155     const char *devaddr;
 156     DriveInfo *dinfo;
 157     int snapshot = 0;
 158     int ret;
 159
 160     *fatal_error = 1;
 161
 162     translation = BIOS_ATA_TRANSLATION_AUTO;
 163
 164     if (default_to_scsi) {
 165         type = IF_SCSI;
 166         max_devs = MAX_SCSI_DEVS;
 167         pstrcpy(devname, sizeof(devname), "scsi");
 168     } else {
 169         type = IF_IDE;
 170         max_devs = MAX_IDE_DEVS;
 171         pstrcpy(devname, sizeof(devname), "ide");
 172     }
 173     media = MEDIA_DISK;
 174
 175     /* extract parameters */
 176     bus_id  = qemu_opt_get_number(opts, "bus", 0);
 177     unit_id = qemu_opt_get_number(opts, "unit", -1);
 178     index   = qemu_opt_get_number(opts, "index", -1);
 179
 180     cyls  = qemu_opt_get_number(opts, "cyls", 0);
 181     heads = qemu_opt_get_number(opts, "heads", 0);
 182     secs  = qemu_opt_get_number(opts, "secs", 0);
 183
 184     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
 185     ro = qemu_opt_get_bool(opts, "readonly", 0);
 186
 187     file = qemu_opt_get(opts, "file");
 188     serial = qemu_opt_get(opts, "serial");
 189
 190     if ((buf = qemu_opt_get(opts, "if")) != NULL) {
 191         pstrcpy(devname, sizeof(devname), buf);
 192         if (!strcmp(buf, "ide")) {
 193             type = IF_IDE;
 194             max_devs = MAX_IDE_DEVS;
 195         } else if (!strcmp(buf, "scsi")) {
 196             type = IF_SCSI;
 197             max_devs = MAX_SCSI_DEVS;
 198         } else if (!strcmp(buf, "floppy")) {
 199             type = IF_FLOPPY;
 200             max_devs = 0;
 201         } else if (!strcmp(buf, "pflash")) {
 202             type = IF_PFLASH;
 203             max_devs = 0;
 204         } else if (!strcmp(buf, "mtd")) {
 205             type = IF_MTD;
 206             max_devs = 0;
 207         } else if (!strcmp(buf, "sd")) {
 208             type = IF_SD;
 209             max_devs = 0;
 210         } else if (!strcmp(buf, "virtio")) {
 211             type = IF_VIRTIO;
 212             max_devs = 0;
 213         } else if (!strcmp(buf, "xen")) {
 214             type = IF_XEN;
 215             max_devs = 0;
 216         } else if (!strcmp(buf, "none")) {
 217             type = IF_NONE;
 218             max_devs = 0;
 219         } else {
 220             error_report("unsupported bus type '%s'", buf);
 221             return NULL;
 222         }
 223     }
 224
 225     if (cyls || heads || secs) {
 226         if (cyls < 1 || (type == IF_IDE && cyls > 16383)) {
 227             error_report("invalid physical cyls number");
 228             return NULL;
 229         }
 230         if (heads < 1 || (type == IF_IDE && heads > 16)) {
 231             error_report("invalid physical heads number");
 232             return NULL;
 233         }
 234         if (secs < 1 || (type == IF_IDE && secs > 63)) {
 235             error_report("invalid physical secs number");
 236             return NULL;
 237         }
 238     }
 239
 240     if ((buf = qemu_opt_get(opts, "trans")) != NULL) {
 241         if (!cyls) {
 242             error_report("'%s' trans must be used with cyls,heads and secs",
 243                          buf);
 244             return NULL;
 245         }
 246         if (!strcmp(buf, "none"))
 247             translation = BIOS_ATA_TRANSLATION_NONE;
 248         else if (!strcmp(buf, "lba"))
 249             translation = BIOS_ATA_TRANSLATION_LBA;
 250         else if (!strcmp(buf, "auto"))
 251             translation = BIOS_ATA_TRANSLATION_AUTO;
 252         else {
 253             error_report("'%s' invalid translation type", buf);
 254             return NULL;
 255         }
 256     }
 257
 258     if ((buf = qemu_opt_get(opts, "media")) != NULL) {
 259         if (!strcmp(buf, "disk")) {
 260             media = MEDIA_DISK;
 261         } else if (!strcmp(buf, "cdrom")) {
 262             if (cyls || secs || heads) {
 263                 error_report("'%s' invalid physical CHS format", buf);
 264                 return NULL;
 265             }
 266             media = MEDIA_CDROM;
 267         } else {
 268             error_report("'%s' invalid media", buf);
 269             return NULL;
 270         }
 271     }
 272
 273     if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
 274         if (!strcmp(buf, "off") || !strcmp(buf, "none")) {
 275             bdrv_flags |= BDRV_O_NOCACHE;
 276         } else if (!strcmp(buf, "writeback")) {
 277             bdrv_flags |= BDRV_O_CACHE_WB;
 278         } else if (!strcmp(buf, "unsafe")) {
 279             bdrv_flags |= BDRV_O_CACHE_WB;
 280             bdrv_flags |= BDRV_O_NO_FLUSH;
 281         } else if (!strcmp(buf, "writethrough")) {
 282             /* this is the default */
 283         } else {
 284            error_report("invalid cache option");
 285            return NULL;
 286         }
 287     }
 288
 289 #ifdef CONFIG_LINUX_AIO
 290     if ((buf = qemu_opt_get(opts, "aio")) != NULL) {
 291         if (!strcmp(buf, "native")) {
 292             bdrv_flags |= BDRV_O_NATIVE_AIO;
 293         } else if (!strcmp(buf, "threads")) {
 294             /* this is the default */
 295         } else {
 296            error_report("invalid aio option");
 297            return NULL;
 298         }
 299     }
 300 #endif
 301
 302     if ((buf = qemu_opt_get(opts, "format")) != NULL) {
 303        if (strcmp(buf, "?") == 0) {
 304            error_printf("Supported formats:");
 305            bdrv_iterate_format(bdrv_format_print, NULL);
 306            error_printf("\n");
 307            return NULL;
 308         }
 309         drv = bdrv_find_whitelisted_format(buf);
 310         if (!drv) {
 311             error_report("'%s' invalid format", buf);
 312             return NULL;
 313         }
 314     }
 315
 316     on_write_error = BLOCK_ERR_STOP_ENOSPC;
 317     if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
 318         if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO && type != IF_NONE) {
 319             error_report("werror is not supported by this bus type");
 320             return NULL;
 321         }
 322
 323         on_write_error = parse_block_error_action(buf, 0);
 324         if (on_write_error < 0) {
 325             return NULL;
 326         }
 327     }
 328
 329     on_read_error = BLOCK_ERR_REPORT;
 330     if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
 331         if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI && type != IF_NONE) {
 332             error_report("rerror is not supported by this bus type");
 333             return NULL;
 334         }
 335
 336         on_read_error = parse_block_error_action(buf, 1);
 337         if (on_read_error < 0) {
 338             return NULL;
 339         }
 340     }
 341
 342     if ((devaddr = qemu_opt_get(opts, "addr")) != NULL) {
 343         if (type != IF_VIRTIO) {
 344             error_report("addr is not supported by this bus type");
 345             return NULL;
 346         }
 347     }
 348
 349     /* compute bus and unit according index */
 350
 351     if (index != -1) {
 352         if (bus_id != 0 || unit_id != -1) {
 353             error_report("index cannot be used with bus and unit");
 354             return NULL;
 355         }
 356         if (max_devs == 0)
 357         {
 358             unit_id = index;
 359             bus_id = 0;
 360         } else {
 361             unit_id = index % max_devs;
 362             bus_id = index / max_devs;
 363         }
 364     }
 365
 366     /* if user doesn't specify a unit_id,
 367      * try to find the first free
 368      */
 369
 370     if (unit_id == -1) {
 371        unit_id = 0;
 372        while (drive_get(type, bus_id, unit_id) != NULL) {
 373            unit_id++;
 374            if (max_devs && unit_id >= max_devs) {
 375                unit_id -= max_devs;
 376                bus_id++;
 377            }
 378        }
 379     }
 380
 381     /* check unit id */
 382
 383     if (max_devs && unit_id >= max_devs) {
 384         error_report("unit %d too big (max is %d)",
 385                      unit_id, max_devs - 1);
 386         return NULL;
 387     }
 388
 389     /*
 390      * ignore multiple definitions
 391      */
 392
 393     if (drive_get(type, bus_id, unit_id) != NULL) {
 394         *fatal_error = 0;
 395         return NULL;
 396     }
 397
 398     /* init */
 399
 400     dinfo = qemu_mallocz(sizeof(*dinfo));
 401     if ((buf = qemu_opts_id(opts)) != NULL) {
 402         dinfo->id = qemu_strdup(buf);
 403     } else {
 404         /* no id supplied -> create one */
 405         dinfo->id = qemu_mallocz(32);
 406         if (type == IF_IDE || type == IF_SCSI)
 407             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
 408         if (max_devs)
 409             snprintf(dinfo->id, 32, "%s%i%s%i",
 410                      devname, bus_id, mediastr, unit_id);
 411         else
 412             snprintf(dinfo->id, 32, "%s%s%i",
 413                      devname, mediastr, unit_id);
 414     }
 415     dinfo->bdrv = bdrv_new(dinfo->id);
 416     dinfo->devaddr = devaddr;
 417     dinfo->type = type;
 418     dinfo->bus = bus_id;
 419     dinfo->unit = unit_id;
 420     dinfo->opts = opts;
 421     if (serial)
 422         strncpy(dinfo->serial, serial, sizeof(dinfo->serial) - 1);
 423     QTAILQ_INSERT_TAIL(&drives, dinfo, next);
 424
 425     bdrv_set_on_error(dinfo->bdrv, on_read_error, on_write_error);
 426
 427     switch(type) {
 428     case IF_IDE:
 429     case IF_SCSI:
 430     case IF_XEN:
 431     case IF_NONE:
 432         switch(media) {
 433         case MEDIA_DISK:
 434             if (cyls != 0) {
 435                 bdrv_set_geometry_hint(dinfo->bdrv, cyls, heads, secs);
 436                 bdrv_set_translation_hint(dinfo->bdrv, translation);
 437             }
 438             break;
 439         case MEDIA_CDROM:
 440             bdrv_set_type_hint(dinfo->bdrv, BDRV_TYPE_CDROM);
 441             break;
 442         }
 443         break;
 444     case IF_SD:
 445         /* FIXME: This isn't really a floppy, but it's a reasonable
 446            approximation.  */
 447     case IF_FLOPPY:
 448         bdrv_set_type_hint(dinfo->bdrv, BDRV_TYPE_FLOPPY);
 449         break;
 450     case IF_PFLASH:
 451     case IF_MTD:
 452         break;
 453     case IF_VIRTIO:
 454         /* add virtio block device */
 455         opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0);
 456         qemu_opt_set(opts, "driver", "virtio-blk-pci");
 457         qemu_opt_set(opts, "drive", dinfo->id);
 458         if (devaddr)
 459             qemu_opt_set(opts, "addr", devaddr);
 460         break;
 461     case IF_COUNT:
 462         abort();
 463     }
 464     if (!file || !*file) {
 465         *fatal_error = 0;
 466         return NULL;
 467     }
 468     if (snapshot) {
 469         /* always use cache=unsafe with snapshot */
 470         bdrv_flags &= ~BDRV_O_CACHE_MASK;
 471         bdrv_flags |= (BDRV_O_SNAPSHOT|BDRV_O_CACHE_WB|BDRV_O_NO_FLUSH);
 472     }
 473
 474     if (media == MEDIA_CDROM) {
 475         /* CDROM is fine for any interface, don't check.  */
 476         ro = 1;
 477     } else if (ro == 1) {
 478         if (type != IF_SCSI && type != IF_VIRTIO && type != IF_FLOPPY && type != IF_NONE) {
 479             error_report("readonly not supported by this bus type");
 480             return NULL;
 481         }
 482     }
 483
 484     bdrv_flags |= ro ? 0 : BDRV_O_RDWR;
 485
 486     ret = bdrv_open(dinfo->bdrv, file, bdrv_flags, drv);
 487     if (ret < 0) {
 488         error_report("could not open disk image %s: %s",
 489                      file, strerror(-ret));
 490         return NULL;
 491     }
 492
 493     if (bdrv_key_required(dinfo->bdrv))
 494         autostart = 0;
 495     *fatal_error = 0;
 496     return dinfo;
 497 }
 498
 499 void do_commit(Monitor *mon, const QDict *qdict)
 500 {
 501     const char *device = qdict_get_str(qdict, "device");
 502     BlockDriverState *bs;
 503
 504     if (!strcmp(device, "all")) {
 505         bdrv_commit_all();
 506     } else {
 507         bs = bdrv_find(device);
 508         if (!bs) {
 509             qerror_report(QERR_DEVICE_NOT_FOUND, device);
 510             return;
 511         }
 512         bdrv_commit(bs);
 513     }
 514 }
 515
 516 int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
 517 {
 518     const char *device = qdict_get_str(qdict, "device");
 519     const char *filename = qdict_get_try_str(qdict, "snapshot_file");
 520     const char *format = qdict_get_try_str(qdict, "format");
 521     BlockDriverState *bs;
 522     BlockDriver *drv, *proto_drv;
 523     int ret = 0;
 524     int flags;
 525
 526     if (!filename) {
 527         qerror_report(QERR_MISSING_PARAMETER, "snapshot_file");
 528         ret = -1;
 529         goto out;
 530     }
 531
 532     bs = bdrv_find(device);
 533     if (!bs) {
 534         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 535         ret = -1;
 536         goto out;
 537     }
 538
 539     if (!format) {
 540         format = "qcow2";
 541     }
 542
 543     drv = bdrv_find_format(format);
 544     if (!drv) {
 545         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 546         ret = -1;
 547         goto out;
 548     }
 549
 550     proto_drv = bdrv_find_protocol(filename);
 551     if (!proto_drv) {
 552         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 553         ret = -1;
 554         goto out;
 555     }
 556
 557     ret = bdrv_img_create(filename, format, bs->filename,
 558                           bs->drv->format_name, NULL, -1, bs->open_flags);
 559     if (ret) {
 560         goto out;
 561     }
 562
 563     qemu_aio_flush();
 564     bdrv_flush(bs);
 565
 566     flags = bs->open_flags;
 567     bdrv_close(bs);
 568     ret = bdrv_open(bs, filename, flags, drv);
 569     /*
 570      * If reopening the image file we just created fails, we really
 571      * are in trouble :(
 572      */
 573     if (ret != 0) {
 574         abort();
 575     }
 576 out:
 577     if (ret) {
 578         ret = -1;
 579     }
 580
 581     return ret;
 582 }
 583
 584 static int eject_device(Monitor *mon, BlockDriverState *bs, int force)
 585 {
 586     if (!force) {
 587         if (!bdrv_is_removable(bs)) {
 588             qerror_report(QERR_DEVICE_NOT_REMOVABLE,
 589                            bdrv_get_device_name(bs));
 590             return -1;
 591         }
 592         if (bdrv_is_locked(bs)) {
 593             qerror_report(QERR_DEVICE_LOCKED, bdrv_get_device_name(bs));
 594             return -1;
 595         }
 596     }
 597     bdrv_close(bs);
 598     return 0;
 599 }
 600
 601 int do_eject(Monitor *mon, const QDict *qdict, QObject **ret_data)
 602 {
 603     BlockDriverState *bs;
 604     int force = qdict_get_try_bool(qdict, "force", 0);
 605     const char *filename = qdict_get_str(qdict, "device");
 606
 607     bs = bdrv_find(filename);
 608     if (!bs) {
 609         qerror_report(QERR_DEVICE_NOT_FOUND, filename);
 610         return -1;
 611     }
 612     return eject_device(mon, bs, force);
 613 }
 614
 615 int do_block_set_passwd(Monitor *mon, const QDict *qdict,
 616                         QObject **ret_data)
 617 {
 618     BlockDriverState *bs;
 619     int err;
 620
 621     bs = bdrv_find(qdict_get_str(qdict, "device"));
 622     if (!bs) {
 623         qerror_report(QERR_DEVICE_NOT_FOUND, qdict_get_str(qdict, "device"));
 624         return -1;
 625     }
 626
 627     err = bdrv_set_key(bs, qdict_get_str(qdict, "password"));
 628     if (err == -EINVAL) {
 629         qerror_report(QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
 630         return -1;
 631     } else if (err < 0) {
 632         qerror_report(QERR_INVALID_PASSWORD);
 633         return -1;
 634     }
 635
 636     return 0;
 637 }
 638
 639 int do_change_block(Monitor *mon, const char *device,
 640                     const char *filename, const char *fmt)
 641 {
 642     BlockDriverState *bs;
 643     BlockDriver *drv = NULL;
 644     int bdrv_flags;
 645
 646     bs = bdrv_find(device);
 647     if (!bs) {
 648         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 649         return -1;
 650     }
 651     if (fmt) {
 652         drv = bdrv_find_whitelisted_format(fmt);
 653         if (!drv) {
 654             qerror_report(QERR_INVALID_BLOCK_FORMAT, fmt);
 655             return -1;
 656         }
 657     }
 658     if (eject_device(mon, bs, 0) < 0) {
 659         return -1;
 660     }
 661     bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
 662     bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
 663     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
 664         qerror_report(QERR_OPEN_FILE_FAILED, filename);
 665         return -1;
 666     }
 667     return monitor_read_bdrv_key_start(mon, bs, NULL, NULL);
 668 }
 669
 670 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
 671 {
 672     const char *id = qdict_get_str(qdict, "id");
 673     BlockDriverState *bs;
 674     BlockDriverState **ptr;
 675     Property *prop;
 676
 677     bs = bdrv_find(id);
 678     if (!bs) {
 679         qerror_report(QERR_DEVICE_NOT_FOUND, id);
 680         return -1;
 681     }
 682
 683     /* quiesce block driver; prevent further io */
 684     qemu_aio_flush();
 685     bdrv_flush(bs);
 686     bdrv_close(bs);
 687
 688     /* clean up guest state from pointing to host resource by
 689      * finding and removing DeviceState "drive" property */
 690     if (bs->peer) {
 691         for (prop = bs->peer->info->props; prop && prop->name; prop++) {
 692             if (prop->info->type == PROP_TYPE_DRIVE) {
 693                 ptr = qdev_get_prop_ptr(bs->peer, prop);
 694                 if (*ptr == bs) {
 695                     bdrv_detach(bs, bs->peer);
 696                     *ptr = NULL;
 697                     break;
 698                 }
 699             }
 700         }
 701     }
 702
 703     /* clean up host side */
 704     drive_uninit(drive_get_by_blockdev(bs));
 705
 706     return 0;
 707 }
 708
 709 /*
 710  * XXX: replace the QERR_UNDEFINED_ERROR errors with real values once the
 711  * existing QERR_ macro mess is cleaned up.  A good example for better
 712  * error reports can be found in the qemu-img resize code.
 713  */
 714 int do_block_resize(Monitor *mon, const QDict *qdict, QObject **ret_data)
 715 {
 716     const char *device = qdict_get_str(qdict, "device");
 717     int64_t size = qdict_get_int(qdict, "size");
 718     BlockDriverState *bs;
 719
 720     bs = bdrv_find(device);
 721     if (!bs) {
 722         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 723         return -1;
 724     }
 725
 726     if (size < 0) {
 727         qerror_report(QERR_UNDEFINED_ERROR);
 728         return -1;
 729     }
 730
 731     if (bdrv_truncate(bs, size)) {
 732         qerror_report(QERR_UNDEFINED_ERROR);
 733         return -1;
 734     }
 735
 736     return 0;
 737 }