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_put_ref(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 *optstr)
  97 {
  98     QemuOpts *opts;
  99     char buf[32];
 100
 101     opts = drive_def(optstr);
 102     if (!opts) {
 103         return NULL;
 104     }
 105     if (type != IF_DEFAULT) {
 106         qemu_opt_set(opts, "if", if_name[type]);
 107     }
 108     if (index >= 0) {
 109         snprintf(buf, sizeof(buf), "%d", index);
 110         qemu_opt_set(opts, "index", buf);
 111     }
 112     if (file)
 113         qemu_opt_set(opts, "file", file);
 114     return opts;
 115 }
 116
 117 DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
 118 {
 119     DriveInfo *dinfo;
 120
 121     /* seek interface, bus and unit */
 122
 123     QTAILQ_FOREACH(dinfo, &drives, next) {
 124         if (dinfo->type == type &&
 125             dinfo->bus == bus &&
 126             dinfo->unit == unit)
 127             return dinfo;
 128     }
 129
 130     return NULL;
 131 }
 132
 133 DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
 134 {
 135     return drive_get(type,
 136                      drive_index_to_bus_id(type, index),
 137                      drive_index_to_unit_id(type, index));
 138 }
 139
 140 int drive_get_max_bus(BlockInterfaceType type)
 141 {
 142     int max_bus;
 143     DriveInfo *dinfo;
 144
 145     max_bus = -1;
 146     QTAILQ_FOREACH(dinfo, &drives, next) {
 147         if(dinfo->type == type &&
 148            dinfo->bus > max_bus)
 149             max_bus = dinfo->bus;
 150     }
 151     return max_bus;
 152 }
 153
 154 /* Get a block device.  This should only be used for single-drive devices
 155    (e.g. SD/Floppy/MTD).  Multi-disk devices (scsi/ide) should use the
 156    appropriate bus.  */
 157 DriveInfo *drive_get_next(BlockInterfaceType type)
 158 {
 159     static int next_block_unit[IF_COUNT];
 160
 161     return drive_get(type, 0, next_block_unit[type]++);
 162 }
 163
 164 DriveInfo *drive_get_by_blockdev(BlockDriverState *bs)
 165 {
 166     DriveInfo *dinfo;
 167
 168     QTAILQ_FOREACH(dinfo, &drives, next) {
 169         if (dinfo->bdrv == bs) {
 170             return dinfo;
 171         }
 172     }
 173     return NULL;
 174 }
 175
 176 static void bdrv_format_print(void *opaque, const char *name)
 177 {
 178     error_printf(" %s", name);
 179 }
 180
 181 static void drive_uninit(DriveInfo *dinfo)
 182 {
 183     qemu_opts_del(dinfo->opts);
 184     bdrv_delete(dinfo->bdrv);
 185     g_free(dinfo->id);
 186     QTAILQ_REMOVE(&drives, dinfo, next);
 187     g_free(dinfo);
 188 }
 189
 190 void drive_put_ref(DriveInfo *dinfo)
 191 {
 192     assert(dinfo->refcount);
 193     if (--dinfo->refcount == 0) {
 194         drive_uninit(dinfo);
 195     }
 196 }
 197
 198 void drive_get_ref(DriveInfo *dinfo)
 199 {
 200     dinfo->refcount++;
 201 }
 202
 203 static int parse_block_error_action(const char *buf, int is_read)
 204 {
 205     if (!strcmp(buf, "ignore")) {
 206         return BLOCK_ERR_IGNORE;
 207     } else if (!is_read && !strcmp(buf, "enospc")) {
 208         return BLOCK_ERR_STOP_ENOSPC;
 209     } else if (!strcmp(buf, "stop")) {
 210         return BLOCK_ERR_STOP_ANY;
 211     } else if (!strcmp(buf, "report")) {
 212         return BLOCK_ERR_REPORT;
 213     } else {
 214         error_report("'%s' invalid %s error action",
 215                      buf, is_read ? "read" : "write");
 216         return -1;
 217     }
 218 }
 219
 220 DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
 221 {
 222     const char *buf;
 223     const char *file = NULL;
 224     char devname[128];
 225     const char *serial;
 226     const char *mediastr = "";
 227     BlockInterfaceType type;
 228     enum { MEDIA_DISK, MEDIA_CDROM } media;
 229     int bus_id, unit_id;
 230     int cyls, heads, secs, translation;
 231     BlockDriver *drv = NULL;
 232     int max_devs;
 233     int index;
 234     int ro = 0;
 235     int bdrv_flags = 0;
 236     int on_read_error, on_write_error;
 237     const char *devaddr;
 238     DriveInfo *dinfo;
 239     int snapshot = 0;
 240     int ret;
 241
 242     translation = BIOS_ATA_TRANSLATION_AUTO;
 243     media = MEDIA_DISK;
 244
 245     /* extract parameters */
 246     bus_id  = qemu_opt_get_number(opts, "bus", 0);
 247     unit_id = qemu_opt_get_number(opts, "unit", -1);
 248     index   = qemu_opt_get_number(opts, "index", -1);
 249
 250     cyls  = qemu_opt_get_number(opts, "cyls", 0);
 251     heads = qemu_opt_get_number(opts, "heads", 0);
 252     secs  = qemu_opt_get_number(opts, "secs", 0);
 253
 254     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
 255     ro = qemu_opt_get_bool(opts, "readonly", 0);
 256
 257     file = qemu_opt_get(opts, "file");
 258     serial = qemu_opt_get(opts, "serial");
 259
 260     if ((buf = qemu_opt_get(opts, "if")) != NULL) {
 261         pstrcpy(devname, sizeof(devname), buf);
 262         for (type = 0; type < IF_COUNT && strcmp(buf, if_name[type]); type++)
 263             ;
 264         if (type == IF_COUNT) {
 265             error_report("unsupported bus type '%s'", buf);
 266             return NULL;
 267         }
 268     } else {
 269         type = default_to_scsi ? IF_SCSI : IF_IDE;
 270         pstrcpy(devname, sizeof(devname), if_name[type]);
 271     }
 272
 273     max_devs = if_max_devs[type];
 274
 275     if (cyls || heads || secs) {
 276         if (cyls < 1 || (type == IF_IDE && cyls > 16383)) {
 277             error_report("invalid physical cyls number");
 278             return NULL;
 279         }
 280         if (heads < 1 || (type == IF_IDE && heads > 16)) {
 281             error_report("invalid physical heads number");
 282             return NULL;
 283         }
 284         if (secs < 1 || (type == IF_IDE && secs > 63)) {
 285             error_report("invalid physical secs number");
 286             return NULL;
 287         }
 288     }
 289
 290     if ((buf = qemu_opt_get(opts, "trans")) != NULL) {
 291         if (!cyls) {
 292             error_report("'%s' trans must be used with cyls, heads and secs",
 293                          buf);
 294             return NULL;
 295         }
 296         if (!strcmp(buf, "none"))
 297             translation = BIOS_ATA_TRANSLATION_NONE;
 298         else if (!strcmp(buf, "lba"))
 299             translation = BIOS_ATA_TRANSLATION_LBA;
 300         else if (!strcmp(buf, "auto"))
 301             translation = BIOS_ATA_TRANSLATION_AUTO;
 302         else {
 303             error_report("'%s' invalid translation type", buf);
 304             return NULL;
 305         }
 306     }
 307
 308     if ((buf = qemu_opt_get(opts, "media")) != NULL) {
 309         if (!strcmp(buf, "disk")) {
 310             media = MEDIA_DISK;
 311         } else if (!strcmp(buf, "cdrom")) {
 312             if (cyls || secs || heads) {
 313                 error_report("CHS can't be set with media=%s", buf);
 314                 return NULL;
 315             }
 316             media = MEDIA_CDROM;
 317         } else {
 318             error_report("'%s' invalid media", buf);
 319             return NULL;
 320         }
 321     }
 322
 323     if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
 324         if (bdrv_parse_cache_flags(buf, &bdrv_flags) != 0) {
 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      * catch multiple definitions
 426      */
 427
 428     if (drive_get(type, bus_id, unit_id) != NULL) {
 429         error_report("drive with bus=%d, unit=%d (index=%d) exists",
 430                      bus_id, unit_id, index);
 431         return NULL;
 432     }
 433
 434     /* init */
 435
 436     dinfo = g_malloc0(sizeof(*dinfo));
 437     if ((buf = qemu_opts_id(opts)) != NULL) {
 438         dinfo->id = g_strdup(buf);
 439     } else {
 440         /* no id supplied -> create one */
 441         dinfo->id = g_malloc0(32);
 442         if (type == IF_IDE || type == IF_SCSI)
 443             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
 444         if (max_devs)
 445             snprintf(dinfo->id, 32, "%s%i%s%i",
 446                      devname, bus_id, mediastr, unit_id);
 447         else
 448             snprintf(dinfo->id, 32, "%s%s%i",
 449                      devname, mediastr, unit_id);
 450     }
 451     dinfo->bdrv = bdrv_new(dinfo->id);
 452     dinfo->devaddr = devaddr;
 453     dinfo->type = type;
 454     dinfo->bus = bus_id;
 455     dinfo->unit = unit_id;
 456     dinfo->opts = opts;
 457     dinfo->refcount = 1;
 458     if (serial)
 459         strncpy(dinfo->serial, serial, sizeof(dinfo->serial) - 1);
 460     QTAILQ_INSERT_TAIL(&drives, dinfo, next);
 461
 462     bdrv_set_on_error(dinfo->bdrv, on_read_error, on_write_error);
 463
 464     switch(type) {
 465     case IF_IDE:
 466     case IF_SCSI:
 467     case IF_XEN:
 468     case IF_NONE:
 469         switch(media) {
 470         case MEDIA_DISK:
 471             if (cyls != 0) {
 472                 bdrv_set_geometry_hint(dinfo->bdrv, cyls, heads, secs);
 473                 bdrv_set_translation_hint(dinfo->bdrv, translation);
 474             }
 475             break;
 476         case MEDIA_CDROM:
 477             bdrv_set_removable(dinfo->bdrv, 1);
 478             dinfo->media_cd = 1;
 479             break;
 480         }
 481         break;
 482     case IF_SD:
 483         /* FIXME: This isn't really a floppy, but it's a reasonable
 484            approximation.  */
 485     case IF_FLOPPY:
 486         bdrv_set_removable(dinfo->bdrv, 1);
 487         break;
 488     case IF_PFLASH:
 489     case IF_MTD:
 490         break;
 491     case IF_VIRTIO:
 492         /* add virtio block device */
 493         opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0);
 494         qemu_opt_set(opts, "driver", "virtio-blk");
 495         qemu_opt_set(opts, "drive", dinfo->id);
 496         if (devaddr)
 497             qemu_opt_set(opts, "addr", devaddr);
 498         break;
 499     default:
 500         abort();
 501     }
 502     if (!file || !*file) {
 503         return dinfo;
 504     }
 505     if (snapshot) {
 506         /* always use cache=unsafe with snapshot */
 507         bdrv_flags &= ~BDRV_O_CACHE_MASK;
 508         bdrv_flags |= (BDRV_O_SNAPSHOT|BDRV_O_CACHE_WB|BDRV_O_NO_FLUSH);
 509     }
 510
 511     if (media == MEDIA_CDROM) {
 512         /* CDROM is fine for any interface, don't check.  */
 513         ro = 1;
 514     } else if (ro == 1) {
 515         if (type != IF_SCSI && type != IF_VIRTIO && type != IF_FLOPPY && type != IF_NONE) {
 516             error_report("readonly not supported by this bus type");
 517             goto err;
 518         }
 519     }
 520
 521     bdrv_flags |= ro ? 0 : BDRV_O_RDWR;
 522
 523     ret = bdrv_open(dinfo->bdrv, file, bdrv_flags, drv);
 524     if (ret < 0) {
 525         error_report("could not open disk image %s: %s",
 526                      file, strerror(-ret));
 527         goto err;
 528     }
 529
 530     if (bdrv_key_required(dinfo->bdrv))
 531         autostart = 0;
 532     return dinfo;
 533
 534 err:
 535     bdrv_delete(dinfo->bdrv);
 536     g_free(dinfo->id);
 537     QTAILQ_REMOVE(&drives, dinfo, next);
 538     g_free(dinfo);
 539     return NULL;
 540 }
 541
 542 void do_commit(Monitor *mon, const QDict *qdict)
 543 {
 544     const char *device = qdict_get_str(qdict, "device");
 545     BlockDriverState *bs;
 546
 547     if (!strcmp(device, "all")) {
 548         bdrv_commit_all();
 549     } else {
 550         bs = bdrv_find(device);
 551         if (!bs) {
 552             qerror_report(QERR_DEVICE_NOT_FOUND, device);
 553             return;
 554         }
 555         bdrv_commit(bs);
 556     }
 557 }
 558
 559 int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
 560 {
 561     const char *device = qdict_get_str(qdict, "device");
 562     const char *filename = qdict_get_try_str(qdict, "snapshot-file");
 563     const char *format = qdict_get_try_str(qdict, "format");
 564     BlockDriverState *bs;
 565     BlockDriver *drv, *old_drv, *proto_drv;
 566     int ret = 0;
 567     int flags;
 568     char old_filename[1024];
 569
 570     if (!filename) {
 571         qerror_report(QERR_MISSING_PARAMETER, "snapshot-file");
 572         ret = -1;
 573         goto out;
 574     }
 575
 576     bs = bdrv_find(device);
 577     if (!bs) {
 578         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 579         ret = -1;
 580         goto out;
 581     }
 582
 583     pstrcpy(old_filename, sizeof(old_filename), bs->filename);
 584
 585     old_drv = bs->drv;
 586     flags = bs->open_flags;
 587
 588     if (!format) {
 589         format = "qcow2";
 590     }
 591
 592     drv = bdrv_find_format(format);
 593     if (!drv) {
 594         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 595         ret = -1;
 596         goto out;
 597     }
 598
 599     proto_drv = bdrv_find_protocol(filename);
 600     if (!proto_drv) {
 601         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 602         ret = -1;
 603         goto out;
 604     }
 605
 606     ret = bdrv_img_create(filename, format, bs->filename,
 607                           bs->drv->format_name, NULL, -1, flags);
 608     if (ret) {
 609         goto out;
 610     }
 611
 612     qemu_aio_flush();
 613     bdrv_flush(bs);
 614
 615     bdrv_close(bs);
 616     ret = bdrv_open(bs, filename, flags, drv);
 617     /*
 618      * If reopening the image file we just created fails, fall back
 619      * and try to re-open the original image. If that fails too, we
 620      * are in serious trouble.
 621      */
 622     if (ret != 0) {
 623         ret = bdrv_open(bs, old_filename, flags, old_drv);
 624         if (ret != 0) {
 625             qerror_report(QERR_OPEN_FILE_FAILED, old_filename);
 626         } else {
 627             qerror_report(QERR_OPEN_FILE_FAILED, filename);
 628         }
 629     }
 630 out:
 631     if (ret) {
 632         ret = -1;
 633     }
 634
 635     return ret;
 636 }
 637
 638 static int eject_device(Monitor *mon, BlockDriverState *bs, int force)
 639 {
 640     if (!bdrv_is_removable(bs)) {
 641         qerror_report(QERR_DEVICE_NOT_REMOVABLE, bdrv_get_device_name(bs));
 642         return -1;
 643     }
 644     if (!force && bdrv_is_locked(bs)) {
 645         qerror_report(QERR_DEVICE_LOCKED, bdrv_get_device_name(bs));
 646         return -1;
 647     }
 648     bdrv_close(bs);
 649     return 0;
 650 }
 651
 652 int do_eject(Monitor *mon, const QDict *qdict, QObject **ret_data)
 653 {
 654     BlockDriverState *bs;
 655     int force = qdict_get_try_bool(qdict, "force", 0);
 656     const char *filename = qdict_get_str(qdict, "device");
 657
 658     bs = bdrv_find(filename);
 659     if (!bs) {
 660         qerror_report(QERR_DEVICE_NOT_FOUND, filename);
 661         return -1;
 662     }
 663     return eject_device(mon, bs, force);
 664 }
 665
 666 int do_block_set_passwd(Monitor *mon, const QDict *qdict,
 667                         QObject **ret_data)
 668 {
 669     BlockDriverState *bs;
 670     int err;
 671
 672     bs = bdrv_find(qdict_get_str(qdict, "device"));
 673     if (!bs) {
 674         qerror_report(QERR_DEVICE_NOT_FOUND, qdict_get_str(qdict, "device"));
 675         return -1;
 676     }
 677
 678     err = bdrv_set_key(bs, qdict_get_str(qdict, "password"));
 679     if (err == -EINVAL) {
 680         qerror_report(QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
 681         return -1;
 682     } else if (err < 0) {
 683         qerror_report(QERR_INVALID_PASSWORD);
 684         return -1;
 685     }
 686
 687     return 0;
 688 }
 689
 690 int do_change_block(Monitor *mon, const char *device,
 691                     const char *filename, const char *fmt)
 692 {
 693     BlockDriverState *bs;
 694     BlockDriver *drv = NULL;
 695     int bdrv_flags;
 696
 697     bs = bdrv_find(device);
 698     if (!bs) {
 699         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 700         return -1;
 701     }
 702     if (fmt) {
 703         drv = bdrv_find_whitelisted_format(fmt);
 704         if (!drv) {
 705             qerror_report(QERR_INVALID_BLOCK_FORMAT, fmt);
 706             return -1;
 707         }
 708     }
 709     if (eject_device(mon, bs, 0) < 0) {
 710         return -1;
 711     }
 712     bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
 713     bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
 714     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
 715         qerror_report(QERR_OPEN_FILE_FAILED, filename);
 716         return -1;
 717     }
 718     return monitor_read_bdrv_key_start(mon, bs, NULL, NULL);
 719 }
 720
 721 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
 722 {
 723     const char *id = qdict_get_str(qdict, "id");
 724     BlockDriverState *bs;
 725
 726     bs = bdrv_find(id);
 727     if (!bs) {
 728         qerror_report(QERR_DEVICE_NOT_FOUND, id);
 729         return -1;
 730     }
 731     if (bdrv_in_use(bs)) {
 732         qerror_report(QERR_DEVICE_IN_USE, id);
 733         return -1;
 734     }
 735
 736     /* quiesce block driver; prevent further io */
 737     qemu_aio_flush();
 738     bdrv_flush(bs);
 739     bdrv_close(bs);
 740
 741     /* if we have a device associated with this BlockDriverState (bs->peer)
 742      * then we need to make the drive anonymous until the device
 743      * can be removed.  If this is a drive with no device backing
 744      * then we can just get rid of the block driver state right here.
 745      */
 746     if (bs->peer) {
 747         bdrv_make_anon(bs);
 748     } else {
 749         drive_uninit(drive_get_by_blockdev(bs));
 750     }
 751
 752     return 0;
 753 }
 754
 755 /*
 756  * XXX: replace the QERR_UNDEFINED_ERROR errors with real values once the
 757  * existing QERR_ macro mess is cleaned up.  A good example for better
 758  * error reports can be found in the qemu-img resize code.
 759  */
 760 int do_block_resize(Monitor *mon, const QDict *qdict, QObject **ret_data)
 761 {
 762     const char *device = qdict_get_str(qdict, "device");
 763     int64_t size = qdict_get_int(qdict, "size");
 764     BlockDriverState *bs;
 765
 766     bs = bdrv_find(device);
 767     if (!bs) {
 768         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 769         return -1;
 770     }
 771
 772     if (size < 0) {
 773         qerror_report(QERR_UNDEFINED_ERROR);
 774         return -1;
 775     }
 776
 777     if (bdrv_truncate(bs, size)) {
 778         qerror_report(QERR_UNDEFINED_ERROR);
 779         return -1;
 780     }
 781
 782     return 0;
 783 }