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 static const char *const if_name[IF_COUNT] = {
  23     [IF_NONE] = "none",
  24     [IF_IDE] = "ide",
  25     [IF_SCSI] = "scsi",
  26     [IF_FLOPPY] = "floppy",
  27     [IF_PFLASH] = "pflash",
  28     [IF_MTD] = "mtd",
  29     [IF_SD] = "sd",
  30     [IF_VIRTIO] = "virtio",
  31     [IF_XEN] = "xen",
  32 };
  33
  34 static const int if_max_devs[IF_COUNT] = {
  35     /*
  36      * Do not change these numbers!  They govern how drive option
  37      * index maps to unit and bus.  That mapping is ABI.
  38      *
  39      * All controllers used to imlement if=T drives need to support
  40      * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
  41      * Otherwise, some index values map to "impossible" bus, unit
  42      * values.
  43      *
  44      * For instance, if you change [IF_SCSI] to 255, -drive
  45      * if=scsi,index=12 no longer means bus=1,unit=5, but
  46      * bus=0,unit=12.  With an lsi53c895a controller (7 units max),
  47      * the drive can't be set up.  Regression.
  48      */
  49     [IF_IDE] = 2,
  50     [IF_SCSI] = 7,
  51 };
  52
  53 /*
  54  * We automatically delete the drive when a device using it gets
  55  * unplugged.  Questionable feature, but we can't just drop it.
  56  * Device models call blockdev_mark_auto_del() to schedule the
  57  * automatic deletion, and generic qdev code calls blockdev_auto_del()
  58  * when deletion is actually safe.
  59  */
  60 void blockdev_mark_auto_del(BlockDriverState *bs)
  61 {
  62     DriveInfo *dinfo = drive_get_by_blockdev(bs);
  63
  64     if (dinfo) {
  65         dinfo->auto_del = 1;
  66     }
  67 }
  68
  69 void blockdev_auto_del(BlockDriverState *bs)
  70 {
  71     DriveInfo *dinfo = drive_get_by_blockdev(bs);
  72
  73     if (dinfo && dinfo->auto_del) {
  74         drive_uninit(dinfo);
  75     }
  76 }
  77
  78 static int drive_index_to_bus_id(BlockInterfaceType type, int index)
  79 {
  80     int max_devs = if_max_devs[type];
  81     return max_devs ? index / max_devs : 0;
  82 }
  83
  84 static int drive_index_to_unit_id(BlockInterfaceType type, int index)
  85 {
  86     int max_devs = if_max_devs[type];
  87     return max_devs ? index % max_devs : index;
  88 }
  89
  90 QemuOpts *drive_def(const char *optstr)
  91 {
  92     return qemu_opts_parse(qemu_find_opts("drive"), optstr, 0);
  93 }
  94
  95 QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
  96                     const char *fmt, ...)
  97 {
  98     va_list ap;
  99     char optstr[1024];
 100     QemuOpts *opts;
 101     char buf[32];
 102
 103     va_start(ap, fmt);
 104     vsnprintf(optstr, sizeof(optstr), fmt, ap);
 105     va_end(ap);
 106
 107     opts = drive_def(optstr);
 108     if (!opts) {
 109         return NULL;
 110     }
 111     if (type != IF_DEFAULT) {
 112         qemu_opt_set(opts, "if", if_name[type]);
 113     }
 114     if (index >= 0) {
 115         snprintf(buf, sizeof(buf), "%d", index);
 116         qemu_opt_set(opts, "index", buf);
 117     }
 118     if (file)
 119         qemu_opt_set(opts, "file", file);
 120     return opts;
 121 }
 122
 123 DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
 124 {
 125     DriveInfo *dinfo;
 126
 127     /* seek interface, bus and unit */
 128
 129     QTAILQ_FOREACH(dinfo, &drives, next) {
 130         if (dinfo->type == type &&
 131             dinfo->bus == bus &&
 132             dinfo->unit == unit)
 133             return dinfo;
 134     }
 135
 136     return NULL;
 137 }
 138
 139 int drive_get_max_bus(BlockInterfaceType type)
 140 {
 141     int max_bus;
 142     DriveInfo *dinfo;
 143
 144     max_bus = -1;
 145     QTAILQ_FOREACH(dinfo, &drives, next) {
 146         if(dinfo->type == type &&
 147            dinfo->bus > max_bus)
 148             max_bus = dinfo->bus;
 149     }
 150     return max_bus;
 151 }
 152
 153 /* Get a block device.  This should only be used for single-drive devices
 154    (e.g. SD/Floppy/MTD).  Multi-disk devices (scsi/ide) should use the
 155    appropriate bus.  */
 156 DriveInfo *drive_get_next(BlockInterfaceType type)
 157 {
 158     static int next_block_unit[IF_COUNT];
 159
 160     return drive_get(type, 0, next_block_unit[type]++);
 161 }
 162
 163 DriveInfo *drive_get_by_blockdev(BlockDriverState *bs)
 164 {
 165     DriveInfo *dinfo;
 166
 167     QTAILQ_FOREACH(dinfo, &drives, next) {
 168         if (dinfo->bdrv == bs) {
 169             return dinfo;
 170         }
 171     }
 172     return NULL;
 173 }
 174
 175 static void bdrv_format_print(void *opaque, const char *name)
 176 {
 177     error_printf(" %s", name);
 178 }
 179
 180 void drive_uninit(DriveInfo *dinfo)
 181 {
 182     qemu_opts_del(dinfo->opts);
 183     bdrv_delete(dinfo->bdrv);
 184     QTAILQ_REMOVE(&drives, dinfo, next);
 185     qemu_free(dinfo);
 186 }
 187
 188 static int parse_block_error_action(const char *buf, int is_read)
 189 {
 190     if (!strcmp(buf, "ignore")) {
 191         return BLOCK_ERR_IGNORE;
 192     } else if (!is_read && !strcmp(buf, "enospc")) {
 193         return BLOCK_ERR_STOP_ENOSPC;
 194     } else if (!strcmp(buf, "stop")) {
 195         return BLOCK_ERR_STOP_ANY;
 196     } else if (!strcmp(buf, "report")) {
 197         return BLOCK_ERR_REPORT;
 198     } else {
 199         error_report("'%s' invalid %s error action",
 200                      buf, is_read ? "read" : "write");
 201         return -1;
 202     }
 203 }
 204
 205 DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error)
 206 {
 207     const char *buf;
 208     const char *file = NULL;
 209     char devname[128];
 210     const char *serial;
 211     const char *mediastr = "";
 212     BlockInterfaceType type;
 213     enum { MEDIA_DISK, MEDIA_CDROM } media;
 214     int bus_id, unit_id;
 215     int cyls, heads, secs, translation;
 216     BlockDriver *drv = NULL;
 217     int max_devs;
 218     int index;
 219     int ro = 0;
 220     int bdrv_flags = 0;
 221     int on_read_error, on_write_error;
 222     const char *devaddr;
 223     DriveInfo *dinfo;
 224     int snapshot = 0;
 225     int ret;
 226
 227     *fatal_error = 1;
 228
 229     translation = BIOS_ATA_TRANSLATION_AUTO;
 230
 231     if (default_to_scsi) {
 232         type = IF_SCSI;
 233         pstrcpy(devname, sizeof(devname), "scsi");
 234     } else {
 235         type = IF_IDE;
 236         pstrcpy(devname, sizeof(devname), "ide");
 237     }
 238     media = MEDIA_DISK;
 239
 240     /* extract parameters */
 241     bus_id  = qemu_opt_get_number(opts, "bus", 0);
 242     unit_id = qemu_opt_get_number(opts, "unit", -1);
 243     index   = qemu_opt_get_number(opts, "index", -1);
 244
 245     cyls  = qemu_opt_get_number(opts, "cyls", 0);
 246     heads = qemu_opt_get_number(opts, "heads", 0);
 247     secs  = qemu_opt_get_number(opts, "secs", 0);
 248
 249     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
 250     ro = qemu_opt_get_bool(opts, "readonly", 0);
 251
 252     file = qemu_opt_get(opts, "file");
 253     serial = qemu_opt_get(opts, "serial");
 254
 255     if ((buf = qemu_opt_get(opts, "if")) != NULL) {
 256         pstrcpy(devname, sizeof(devname), buf);
 257         for (type = 0; type < IF_COUNT && strcmp(buf, if_name[type]); type++)
 258             ;
 259         if (type == IF_COUNT) {
 260             error_report("unsupported bus type '%s'", buf);
 261             return NULL;
 262         }
 263     }
 264     max_devs = if_max_devs[type];
 265
 266     if (cyls || heads || secs) {
 267         if (cyls < 1 || (type == IF_IDE && cyls > 16383)) {
 268             error_report("invalid physical cyls number");
 269             return NULL;
 270         }
 271         if (heads < 1 || (type == IF_IDE && heads > 16)) {
 272             error_report("invalid physical heads number");
 273             return NULL;
 274         }
 275         if (secs < 1 || (type == IF_IDE && secs > 63)) {
 276             error_report("invalid physical secs number");
 277             return NULL;
 278         }
 279     }
 280
 281     if ((buf = qemu_opt_get(opts, "trans")) != NULL) {
 282         if (!cyls) {
 283             error_report("'%s' trans must be used with cyls,heads and secs",
 284                          buf);
 285             return NULL;
 286         }
 287         if (!strcmp(buf, "none"))
 288             translation = BIOS_ATA_TRANSLATION_NONE;
 289         else if (!strcmp(buf, "lba"))
 290             translation = BIOS_ATA_TRANSLATION_LBA;
 291         else if (!strcmp(buf, "auto"))
 292             translation = BIOS_ATA_TRANSLATION_AUTO;
 293         else {
 294             error_report("'%s' invalid translation type", buf);
 295             return NULL;
 296         }
 297     }
 298
 299     if ((buf = qemu_opt_get(opts, "media")) != NULL) {
 300         if (!strcmp(buf, "disk")) {
 301             media = MEDIA_DISK;
 302         } else if (!strcmp(buf, "cdrom")) {
 303             if (cyls || secs || heads) {
 304                 error_report("'%s' invalid physical CHS format", buf);
 305                 return NULL;
 306             }
 307             media = MEDIA_CDROM;
 308         } else {
 309             error_report("'%s' invalid media", buf);
 310             return NULL;
 311         }
 312     }
 313
 314     if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
 315         if (!strcmp(buf, "off") || !strcmp(buf, "none")) {
 316             bdrv_flags |= BDRV_O_NOCACHE;
 317         } else if (!strcmp(buf, "writeback")) {
 318             bdrv_flags |= BDRV_O_CACHE_WB;
 319         } else if (!strcmp(buf, "unsafe")) {
 320             bdrv_flags |= BDRV_O_CACHE_WB;
 321             bdrv_flags |= BDRV_O_NO_FLUSH;
 322         } else if (!strcmp(buf, "writethrough")) {
 323             /* this is the default */
 324         } else {
 325            error_report("invalid cache option");
 326            return NULL;
 327         }
 328     }
 329
 330 #ifdef CONFIG_LINUX_AIO
 331     if ((buf = qemu_opt_get(opts, "aio")) != NULL) {
 332         if (!strcmp(buf, "native")) {
 333             bdrv_flags |= BDRV_O_NATIVE_AIO;
 334         } else if (!strcmp(buf, "threads")) {
 335             /* this is the default */
 336         } else {
 337            error_report("invalid aio option");
 338            return NULL;
 339         }
 340     }
 341 #endif
 342
 343     if ((buf = qemu_opt_get(opts, "format")) != NULL) {
 344        if (strcmp(buf, "?") == 0) {
 345            error_printf("Supported formats:");
 346            bdrv_iterate_format(bdrv_format_print, NULL);
 347            error_printf("\n");
 348            return NULL;
 349         }
 350         drv = bdrv_find_whitelisted_format(buf);
 351         if (!drv) {
 352             error_report("'%s' invalid format", buf);
 353             return NULL;
 354         }
 355     }
 356
 357     on_write_error = BLOCK_ERR_STOP_ENOSPC;
 358     if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
 359         if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO && type != IF_NONE) {
 360             error_report("werror is not supported by this bus type");
 361             return NULL;
 362         }
 363
 364         on_write_error = parse_block_error_action(buf, 0);
 365         if (on_write_error < 0) {
 366             return NULL;
 367         }
 368     }
 369
 370     on_read_error = BLOCK_ERR_REPORT;
 371     if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
 372         if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI && type != IF_NONE) {
 373             error_report("rerror is not supported by this bus type");
 374             return NULL;
 375         }
 376
 377         on_read_error = parse_block_error_action(buf, 1);
 378         if (on_read_error < 0) {
 379             return NULL;
 380         }
 381     }
 382
 383     if ((devaddr = qemu_opt_get(opts, "addr")) != NULL) {
 384         if (type != IF_VIRTIO) {
 385             error_report("addr is not supported by this bus type");
 386             return NULL;
 387         }
 388     }
 389
 390     /* compute bus and unit according index */
 391
 392     if (index != -1) {
 393         if (bus_id != 0 || unit_id != -1) {
 394             error_report("index cannot be used with bus and unit");
 395             return NULL;
 396         }
 397         bus_id = drive_index_to_bus_id(type, index);
 398         unit_id = drive_index_to_unit_id(type, index);
 399     }
 400
 401     /* if user doesn't specify a unit_id,
 402      * try to find the first free
 403      */
 404
 405     if (unit_id == -1) {
 406        unit_id = 0;
 407        while (drive_get(type, bus_id, unit_id) != NULL) {
 408            unit_id++;
 409            if (max_devs && unit_id >= max_devs) {
 410                unit_id -= max_devs;
 411                bus_id++;
 412            }
 413        }
 414     }
 415
 416     /* check unit id */
 417
 418     if (max_devs && unit_id >= max_devs) {
 419         error_report("unit %d too big (max is %d)",
 420                      unit_id, max_devs - 1);
 421         return NULL;
 422     }
 423
 424     /*
 425      * ignore multiple definitions
 426      */
 427
 428     if (drive_get(type, bus_id, unit_id) != NULL) {
 429         *fatal_error = 0;
 430         return NULL;
 431     }
 432
 433     /* init */
 434
 435     dinfo = qemu_mallocz(sizeof(*dinfo));
 436     if ((buf = qemu_opts_id(opts)) != NULL) {
 437         dinfo->id = qemu_strdup(buf);
 438     } else {
 439         /* no id supplied -> create one */
 440         dinfo->id = qemu_mallocz(32);
 441         if (type == IF_IDE || type == IF_SCSI)
 442             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
 443         if (max_devs)
 444             snprintf(dinfo->id, 32, "%s%i%s%i",
 445                      devname, bus_id, mediastr, unit_id);
 446         else
 447             snprintf(dinfo->id, 32, "%s%s%i",
 448                      devname, mediastr, unit_id);
 449     }
 450     dinfo->bdrv = bdrv_new(dinfo->id);
 451     dinfo->devaddr = devaddr;
 452     dinfo->type = type;
 453     dinfo->bus = bus_id;
 454     dinfo->unit = unit_id;
 455     dinfo->opts = opts;
 456     if (serial)
 457         strncpy(dinfo->serial, serial, sizeof(dinfo->serial) - 1);
 458     QTAILQ_INSERT_TAIL(&drives, dinfo, next);
 459
 460     bdrv_set_on_error(dinfo->bdrv, on_read_error, on_write_error);
 461
 462     switch(type) {
 463     case IF_IDE:
 464     case IF_SCSI:
 465     case IF_XEN:
 466     case IF_NONE:
 467         switch(media) {
 468         case MEDIA_DISK:
 469             if (cyls != 0) {
 470                 bdrv_set_geometry_hint(dinfo->bdrv, cyls, heads, secs);
 471                 bdrv_set_translation_hint(dinfo->bdrv, translation);
 472             }
 473             break;
 474         case MEDIA_CDROM:
 475             bdrv_set_type_hint(dinfo->bdrv, BDRV_TYPE_CDROM);
 476             break;
 477         }
 478         break;
 479     case IF_SD:
 480         /* FIXME: This isn't really a floppy, but it's a reasonable
 481            approximation.  */
 482     case IF_FLOPPY:
 483         bdrv_set_type_hint(dinfo->bdrv, BDRV_TYPE_FLOPPY);
 484         break;
 485     case IF_PFLASH:
 486     case IF_MTD:
 487         break;
 488     case IF_VIRTIO:
 489         /* add virtio block device */
 490         opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0);
 491         qemu_opt_set(opts, "driver", "virtio-blk-pci");
 492         qemu_opt_set(opts, "drive", dinfo->id);
 493         if (devaddr)
 494             qemu_opt_set(opts, "addr", devaddr);
 495         break;
 496     default:
 497         abort();
 498     }
 499     if (!file || !*file) {
 500         *fatal_error = 0;
 501         return NULL;
 502     }
 503     if (snapshot) {
 504         /* always use cache=unsafe with snapshot */
 505         bdrv_flags &= ~BDRV_O_CACHE_MASK;
 506         bdrv_flags |= (BDRV_O_SNAPSHOT|BDRV_O_CACHE_WB|BDRV_O_NO_FLUSH);
 507     }
 508
 509     if (media == MEDIA_CDROM) {
 510         /* CDROM is fine for any interface, don't check.  */
 511         ro = 1;
 512     } else if (ro == 1) {
 513         if (type != IF_SCSI && type != IF_VIRTIO && type != IF_FLOPPY && type != IF_NONE) {
 514             error_report("readonly not supported by this bus type");
 515             return NULL;
 516         }
 517     }
 518
 519     bdrv_flags |= ro ? 0 : BDRV_O_RDWR;
 520
 521     ret = bdrv_open(dinfo->bdrv, file, bdrv_flags, drv);
 522     if (ret < 0) {
 523         error_report("could not open disk image %s: %s",
 524                      file, strerror(-ret));
 525         return NULL;
 526     }
 527
 528     if (bdrv_key_required(dinfo->bdrv))
 529         autostart = 0;
 530     *fatal_error = 0;
 531     return dinfo;
 532 }
 533
 534 void do_commit(Monitor *mon, const QDict *qdict)
 535 {
 536     const char *device = qdict_get_str(qdict, "device");
 537     BlockDriverState *bs;
 538
 539     if (!strcmp(device, "all")) {
 540         bdrv_commit_all();
 541     } else {
 542         bs = bdrv_find(device);
 543         if (!bs) {
 544             qerror_report(QERR_DEVICE_NOT_FOUND, device);
 545             return;
 546         }
 547         bdrv_commit(bs);
 548     }
 549 }
 550
 551 int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
 552 {
 553     const char *device = qdict_get_str(qdict, "device");
 554     const char *filename = qdict_get_try_str(qdict, "snapshot_file");
 555     const char *format = qdict_get_try_str(qdict, "format");
 556     BlockDriverState *bs;
 557     BlockDriver *drv, *proto_drv;
 558     int ret = 0;
 559     int flags;
 560
 561     if (!filename) {
 562         qerror_report(QERR_MISSING_PARAMETER, "snapshot_file");
 563         ret = -1;
 564         goto out;
 565     }
 566
 567     bs = bdrv_find(device);
 568     if (!bs) {
 569         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 570         ret = -1;
 571         goto out;
 572     }
 573
 574     if (!format) {
 575         format = "qcow2";
 576     }
 577
 578     drv = bdrv_find_format(format);
 579     if (!drv) {
 580         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 581         ret = -1;
 582         goto out;
 583     }
 584
 585     proto_drv = bdrv_find_protocol(filename);
 586     if (!proto_drv) {
 587         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 588         ret = -1;
 589         goto out;
 590     }
 591
 592     ret = bdrv_img_create(filename, format, bs->filename,
 593                           bs->drv->format_name, NULL, -1, bs->open_flags);
 594     if (ret) {
 595         goto out;
 596     }
 597
 598     qemu_aio_flush();
 599     bdrv_flush(bs);
 600
 601     flags = bs->open_flags;
 602     bdrv_close(bs);
 603     ret = bdrv_open(bs, filename, flags, drv);
 604     /*
 605      * If reopening the image file we just created fails, we really
 606      * are in trouble :(
 607      */
 608     if (ret != 0) {
 609         abort();
 610     }
 611 out:
 612     if (ret) {
 613         ret = -1;
 614     }
 615
 616     return ret;
 617 }
 618
 619 static int eject_device(Monitor *mon, BlockDriverState *bs, int force)
 620 {
 621     if (!force) {
 622         if (!bdrv_is_removable(bs)) {
 623             qerror_report(QERR_DEVICE_NOT_REMOVABLE,
 624                            bdrv_get_device_name(bs));
 625             return -1;
 626         }
 627         if (bdrv_is_locked(bs)) {
 628             qerror_report(QERR_DEVICE_LOCKED, bdrv_get_device_name(bs));
 629             return -1;
 630         }
 631     }
 632     bdrv_close(bs);
 633     return 0;
 634 }
 635
 636 int do_eject(Monitor *mon, const QDict *qdict, QObject **ret_data)
 637 {
 638     BlockDriverState *bs;
 639     int force = qdict_get_try_bool(qdict, "force", 0);
 640     const char *filename = qdict_get_str(qdict, "device");
 641
 642     bs = bdrv_find(filename);
 643     if (!bs) {
 644         qerror_report(QERR_DEVICE_NOT_FOUND, filename);
 645         return -1;
 646     }
 647     return eject_device(mon, bs, force);
 648 }
 649
 650 int do_block_set_passwd(Monitor *mon, const QDict *qdict,
 651                         QObject **ret_data)
 652 {
 653     BlockDriverState *bs;
 654     int err;
 655
 656     bs = bdrv_find(qdict_get_str(qdict, "device"));
 657     if (!bs) {
 658         qerror_report(QERR_DEVICE_NOT_FOUND, qdict_get_str(qdict, "device"));
 659         return -1;
 660     }
 661
 662     err = bdrv_set_key(bs, qdict_get_str(qdict, "password"));
 663     if (err == -EINVAL) {
 664         qerror_report(QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
 665         return -1;
 666     } else if (err < 0) {
 667         qerror_report(QERR_INVALID_PASSWORD);
 668         return -1;
 669     }
 670
 671     return 0;
 672 }
 673
 674 int do_change_block(Monitor *mon, const char *device,
 675                     const char *filename, const char *fmt)
 676 {
 677     BlockDriverState *bs;
 678     BlockDriver *drv = NULL;
 679     int bdrv_flags;
 680
 681     bs = bdrv_find(device);
 682     if (!bs) {
 683         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 684         return -1;
 685     }
 686     if (fmt) {
 687         drv = bdrv_find_whitelisted_format(fmt);
 688         if (!drv) {
 689             qerror_report(QERR_INVALID_BLOCK_FORMAT, fmt);
 690             return -1;
 691         }
 692     }
 693     if (eject_device(mon, bs, 0) < 0) {
 694         return -1;
 695     }
 696     bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
 697     bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
 698     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
 699         qerror_report(QERR_OPEN_FILE_FAILED, filename);
 700         return -1;
 701     }
 702     return monitor_read_bdrv_key_start(mon, bs, NULL, NULL);
 703 }
 704
 705 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
 706 {
 707     const char *id = qdict_get_str(qdict, "id");
 708     BlockDriverState *bs;
 709     BlockDriverState **ptr;
 710     Property *prop;
 711
 712     bs = bdrv_find(id);
 713     if (!bs) {
 714         qerror_report(QERR_DEVICE_NOT_FOUND, id);
 715         return -1;
 716     }
 717
 718     /* quiesce block driver; prevent further io */
 719     qemu_aio_flush();
 720     bdrv_flush(bs);
 721     bdrv_close(bs);
 722
 723     /* clean up guest state from pointing to host resource by
 724      * finding and removing DeviceState "drive" property */
 725     if (bs->peer) {
 726         for (prop = bs->peer->info->props; prop && prop->name; prop++) {
 727             if (prop->info->type == PROP_TYPE_DRIVE) {
 728                 ptr = qdev_get_prop_ptr(bs->peer, prop);
 729                 if (*ptr == bs) {
 730                     bdrv_detach(bs, bs->peer);
 731                     *ptr = NULL;
 732                     break;
 733                 }
 734             }
 735         }
 736     }
 737
 738     /* clean up host side */
 739     drive_uninit(drive_get_by_blockdev(bs));
 740
 741     return 0;
 742 }
 743
 744 /*
 745  * XXX: replace the QERR_UNDEFINED_ERROR errors with real values once the
 746  * existing QERR_ macro mess is cleaned up.  A good example for better
 747  * error reports can be found in the qemu-img resize code.
 748  */
 749 int do_block_resize(Monitor *mon, const QDict *qdict, QObject **ret_data)
 750 {
 751     const char *device = qdict_get_str(qdict, "device");
 752     int64_t size = qdict_get_int(qdict, "size");
 753     BlockDriverState *bs;
 754
 755     bs = bdrv_find(device);
 756     if (!bs) {
 757         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 758         return -1;
 759     }
 760
 761     if (size < 0) {
 762         qerror_report(QERR_UNDEFINED_ERROR);
 763         return -1;
 764     }
 765
 766     if (bdrv_truncate(bs, size)) {
 767         qerror_report(QERR_UNDEFINED_ERROR);
 768         return -1;
 769     }
 770
 771     return 0;
 772 }