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 *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 void drive_uninit(DriveInfo *dinfo)
 182 {
 183     qemu_opts_del(dinfo->opts);
 184     bdrv_delete(dinfo->bdrv);
 185     QTAILQ_REMOVE(&drives, dinfo, next);
 186     qemu_free(dinfo);
 187 }
 188
 189 static int parse_block_error_action(const char *buf, int is_read)
 190 {
 191     if (!strcmp(buf, "ignore")) {
 192         return BLOCK_ERR_IGNORE;
 193     } else if (!is_read && !strcmp(buf, "enospc")) {
 194         return BLOCK_ERR_STOP_ENOSPC;
 195     } else if (!strcmp(buf, "stop")) {
 196         return BLOCK_ERR_STOP_ANY;
 197     } else if (!strcmp(buf, "report")) {
 198         return BLOCK_ERR_REPORT;
 199     } else {
 200         error_report("'%s' invalid %s error action",
 201                      buf, is_read ? "read" : "write");
 202         return -1;
 203     }
 204 }
 205
 206 DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error)
 207 {
 208     const char *buf;
 209     const char *file = NULL;
 210     char devname[128];
 211     const char *serial;
 212     const char *mediastr = "";
 213     BlockInterfaceType type;
 214     enum { MEDIA_DISK, MEDIA_CDROM } media;
 215     int bus_id, unit_id;
 216     int cyls, heads, secs, translation;
 217     BlockDriver *drv = NULL;
 218     int max_devs;
 219     int index;
 220     int ro = 0;
 221     int bdrv_flags = 0;
 222     int on_read_error, on_write_error;
 223     const char *devaddr;
 224     DriveInfo *dinfo;
 225     int snapshot = 0;
 226     int ret;
 227
 228     *fatal_error = 1;
 229
 230     translation = BIOS_ATA_TRANSLATION_AUTO;
 231
 232     if (default_to_scsi) {
 233         type = IF_SCSI;
 234         pstrcpy(devname, sizeof(devname), "scsi");
 235     } else {
 236         type = IF_IDE;
 237         pstrcpy(devname, sizeof(devname), "ide");
 238     }
 239     media = MEDIA_DISK;
 240
 241     /* extract parameters */
 242     bus_id  = qemu_opt_get_number(opts, "bus", 0);
 243     unit_id = qemu_opt_get_number(opts, "unit", -1);
 244     index   = qemu_opt_get_number(opts, "index", -1);
 245
 246     cyls  = qemu_opt_get_number(opts, "cyls", 0);
 247     heads = qemu_opt_get_number(opts, "heads", 0);
 248     secs  = qemu_opt_get_number(opts, "secs", 0);
 249
 250     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
 251     ro = qemu_opt_get_bool(opts, "readonly", 0);
 252
 253     file = qemu_opt_get(opts, "file");
 254     serial = qemu_opt_get(opts, "serial");
 255
 256     if ((buf = qemu_opt_get(opts, "if")) != NULL) {
 257         pstrcpy(devname, sizeof(devname), buf);
 258         for (type = 0; type < IF_COUNT && strcmp(buf, if_name[type]); type++)
 259             ;
 260         if (type == IF_COUNT) {
 261             error_report("unsupported bus type '%s'", buf);
 262             return NULL;
 263         }
 264     }
 265     max_devs = if_max_devs[type];
 266
 267     if (cyls || heads || secs) {
 268         if (cyls < 1 || (type == IF_IDE && cyls > 16383)) {
 269             error_report("invalid physical cyls number");
 270             return NULL;
 271         }
 272         if (heads < 1 || (type == IF_IDE && heads > 16)) {
 273             error_report("invalid physical heads number");
 274             return NULL;
 275         }
 276         if (secs < 1 || (type == IF_IDE && secs > 63)) {
 277             error_report("invalid physical secs number");
 278             return NULL;
 279         }
 280     }
 281
 282     if ((buf = qemu_opt_get(opts, "trans")) != NULL) {
 283         if (!cyls) {
 284             error_report("'%s' trans must be used with cyls,heads and secs",
 285                          buf);
 286             return NULL;
 287         }
 288         if (!strcmp(buf, "none"))
 289             translation = BIOS_ATA_TRANSLATION_NONE;
 290         else if (!strcmp(buf, "lba"))
 291             translation = BIOS_ATA_TRANSLATION_LBA;
 292         else if (!strcmp(buf, "auto"))
 293             translation = BIOS_ATA_TRANSLATION_AUTO;
 294         else {
 295             error_report("'%s' invalid translation type", buf);
 296             return NULL;
 297         }
 298     }
 299
 300     if ((buf = qemu_opt_get(opts, "media")) != NULL) {
 301         if (!strcmp(buf, "disk")) {
 302             media = MEDIA_DISK;
 303         } else if (!strcmp(buf, "cdrom")) {
 304             if (cyls || secs || heads) {
 305                 error_report("'%s' invalid physical CHS format", buf);
 306                 return NULL;
 307             }
 308             media = MEDIA_CDROM;
 309         } else {
 310             error_report("'%s' invalid media", buf);
 311             return NULL;
 312         }
 313     }
 314
 315     if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
 316         if (!strcmp(buf, "off") || !strcmp(buf, "none")) {
 317             bdrv_flags |= BDRV_O_NOCACHE;
 318         } else if (!strcmp(buf, "writeback")) {
 319             bdrv_flags |= BDRV_O_CACHE_WB;
 320         } else if (!strcmp(buf, "unsafe")) {
 321             bdrv_flags |= BDRV_O_CACHE_WB;
 322             bdrv_flags |= BDRV_O_NO_FLUSH;
 323         } else if (!strcmp(buf, "writethrough")) {
 324             /* this is the default */
 325         } else {
 326            error_report("invalid cache option");
 327            return NULL;
 328         }
 329     }
 330
 331 #ifdef CONFIG_LINUX_AIO
 332     if ((buf = qemu_opt_get(opts, "aio")) != NULL) {
 333         if (!strcmp(buf, "native")) {
 334             bdrv_flags |= BDRV_O_NATIVE_AIO;
 335         } else if (!strcmp(buf, "threads")) {
 336             /* this is the default */
 337         } else {
 338            error_report("invalid aio option");
 339            return NULL;
 340         }
 341     }
 342 #endif
 343
 344     if ((buf = qemu_opt_get(opts, "format")) != NULL) {
 345        if (strcmp(buf, "?") == 0) {
 346            error_printf("Supported formats:");
 347            bdrv_iterate_format(bdrv_format_print, NULL);
 348            error_printf("\n");
 349            return NULL;
 350         }
 351         drv = bdrv_find_whitelisted_format(buf);
 352         if (!drv) {
 353             error_report("'%s' invalid format", buf);
 354             return NULL;
 355         }
 356     }
 357
 358     on_write_error = BLOCK_ERR_STOP_ENOSPC;
 359     if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
 360         if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO && type != IF_NONE) {
 361             error_report("werror is not supported by this bus type");
 362             return NULL;
 363         }
 364
 365         on_write_error = parse_block_error_action(buf, 0);
 366         if (on_write_error < 0) {
 367             return NULL;
 368         }
 369     }
 370
 371     on_read_error = BLOCK_ERR_REPORT;
 372     if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
 373         if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI && type != IF_NONE) {
 374             error_report("rerror is not supported by this bus type");
 375             return NULL;
 376         }
 377
 378         on_read_error = parse_block_error_action(buf, 1);
 379         if (on_read_error < 0) {
 380             return NULL;
 381         }
 382     }
 383
 384     if ((devaddr = qemu_opt_get(opts, "addr")) != NULL) {
 385         if (type != IF_VIRTIO) {
 386             error_report("addr is not supported by this bus type");
 387             return NULL;
 388         }
 389     }
 390
 391     /* compute bus and unit according index */
 392
 393     if (index != -1) {
 394         if (bus_id != 0 || unit_id != -1) {
 395             error_report("index cannot be used with bus and unit");
 396             return NULL;
 397         }
 398         bus_id = drive_index_to_bus_id(type, index);
 399         unit_id = drive_index_to_unit_id(type, index);
 400     }
 401
 402     /* if user doesn't specify a unit_id,
 403      * try to find the first free
 404      */
 405
 406     if (unit_id == -1) {
 407        unit_id = 0;
 408        while (drive_get(type, bus_id, unit_id) != NULL) {
 409            unit_id++;
 410            if (max_devs && unit_id >= max_devs) {
 411                unit_id -= max_devs;
 412                bus_id++;
 413            }
 414        }
 415     }
 416
 417     /* check unit id */
 418
 419     if (max_devs && unit_id >= max_devs) {
 420         error_report("unit %d too big (max is %d)",
 421                      unit_id, max_devs - 1);
 422         return NULL;
 423     }
 424
 425     /*
 426      * catch multiple definitions
 427      */
 428
 429     if (drive_get(type, bus_id, unit_id) != NULL) {
 430         error_report("drive with bus=%d, unit=%d (index=%d) exists",
 431                      bus_id, unit_id, index);
 432         return NULL;
 433     }
 434
 435     /* init */
 436
 437     dinfo = qemu_mallocz(sizeof(*dinfo));
 438     if ((buf = qemu_opts_id(opts)) != NULL) {
 439         dinfo->id = qemu_strdup(buf);
 440     } else {
 441         /* no id supplied -> create one */
 442         dinfo->id = qemu_mallocz(32);
 443         if (type == IF_IDE || type == IF_SCSI)
 444             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
 445         if (max_devs)
 446             snprintf(dinfo->id, 32, "%s%i%s%i",
 447                      devname, bus_id, mediastr, unit_id);
 448         else
 449             snprintf(dinfo->id, 32, "%s%s%i",
 450                      devname, mediastr, unit_id);
 451     }
 452     dinfo->bdrv = bdrv_new(dinfo->id);
 453     dinfo->devaddr = devaddr;
 454     dinfo->type = type;
 455     dinfo->bus = bus_id;
 456     dinfo->unit = unit_id;
 457     dinfo->opts = opts;
 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_type_hint(dinfo->bdrv, BDRV_TYPE_CDROM);
 478             break;
 479         }
 480         break;
 481     case IF_SD:
 482         /* FIXME: This isn't really a floppy, but it's a reasonable
 483            approximation.  */
 484     case IF_FLOPPY:
 485         bdrv_set_type_hint(dinfo->bdrv, BDRV_TYPE_FLOPPY);
 486         break;
 487     case IF_PFLASH:
 488     case IF_MTD:
 489         break;
 490     case IF_VIRTIO:
 491         /* add virtio block device */
 492         opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0);
 493         qemu_opt_set(opts, "driver", "virtio-blk-pci");
 494         qemu_opt_set(opts, "drive", dinfo->id);
 495         if (devaddr)
 496             qemu_opt_set(opts, "addr", devaddr);
 497         break;
 498     default:
 499         abort();
 500     }
 501     if (!file || !*file) {
 502         *fatal_error = 0;
 503         return NULL;
 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             return NULL;
 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         return NULL;
 528     }
 529
 530     if (bdrv_key_required(dinfo->bdrv))
 531         autostart = 0;
 532     *fatal_error = 0;
 533     return dinfo;
 534 }
 535
 536 void do_commit(Monitor *mon, const QDict *qdict)
 537 {
 538     const char *device = qdict_get_str(qdict, "device");
 539     BlockDriverState *bs;
 540
 541     if (!strcmp(device, "all")) {
 542         bdrv_commit_all();
 543     } else {
 544         bs = bdrv_find(device);
 545         if (!bs) {
 546             qerror_report(QERR_DEVICE_NOT_FOUND, device);
 547             return;
 548         }
 549         bdrv_commit(bs);
 550     }
 551 }
 552
 553 int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
 554 {
 555     const char *device = qdict_get_str(qdict, "device");
 556     const char *filename = qdict_get_try_str(qdict, "snapshot_file");
 557     const char *format = qdict_get_try_str(qdict, "format");
 558     BlockDriverState *bs;
 559     BlockDriver *drv, *proto_drv;
 560     int ret = 0;
 561     int flags;
 562
 563     if (!filename) {
 564         qerror_report(QERR_MISSING_PARAMETER, "snapshot_file");
 565         ret = -1;
 566         goto out;
 567     }
 568
 569     bs = bdrv_find(device);
 570     if (!bs) {
 571         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 572         ret = -1;
 573         goto out;
 574     }
 575
 576     if (!format) {
 577         format = "qcow2";
 578     }
 579
 580     drv = bdrv_find_format(format);
 581     if (!drv) {
 582         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 583         ret = -1;
 584         goto out;
 585     }
 586
 587     proto_drv = bdrv_find_protocol(filename);
 588     if (!proto_drv) {
 589         qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
 590         ret = -1;
 591         goto out;
 592     }
 593
 594     ret = bdrv_img_create(filename, format, bs->filename,
 595                           bs->drv->format_name, NULL, -1, bs->open_flags);
 596     if (ret) {
 597         goto out;
 598     }
 599
 600     qemu_aio_flush();
 601     bdrv_flush(bs);
 602
 603     flags = bs->open_flags;
 604     bdrv_close(bs);
 605     ret = bdrv_open(bs, filename, flags, drv);
 606     /*
 607      * If reopening the image file we just created fails, we really
 608      * are in trouble :(
 609      */
 610     if (ret != 0) {
 611         abort();
 612     }
 613 out:
 614     if (ret) {
 615         ret = -1;
 616     }
 617
 618     return ret;
 619 }
 620
 621 static int eject_device(Monitor *mon, BlockDriverState *bs, int force)
 622 {
 623     if (!force) {
 624         if (!bdrv_is_removable(bs)) {
 625             qerror_report(QERR_DEVICE_NOT_REMOVABLE,
 626                            bdrv_get_device_name(bs));
 627             return -1;
 628         }
 629         if (bdrv_is_locked(bs)) {
 630             qerror_report(QERR_DEVICE_LOCKED, bdrv_get_device_name(bs));
 631             return -1;
 632         }
 633     }
 634     bdrv_close(bs);
 635     return 0;
 636 }
 637
 638 int do_eject(Monitor *mon, const QDict *qdict, QObject **ret_data)
 639 {
 640     BlockDriverState *bs;
 641     int force = qdict_get_try_bool(qdict, "force", 0);
 642     const char *filename = qdict_get_str(qdict, "device");
 643
 644     bs = bdrv_find(filename);
 645     if (!bs) {
 646         qerror_report(QERR_DEVICE_NOT_FOUND, filename);
 647         return -1;
 648     }
 649     return eject_device(mon, bs, force);
 650 }
 651
 652 int do_block_set_passwd(Monitor *mon, const QDict *qdict,
 653                         QObject **ret_data)
 654 {
 655     BlockDriverState *bs;
 656     int err;
 657
 658     bs = bdrv_find(qdict_get_str(qdict, "device"));
 659     if (!bs) {
 660         qerror_report(QERR_DEVICE_NOT_FOUND, qdict_get_str(qdict, "device"));
 661         return -1;
 662     }
 663
 664     err = bdrv_set_key(bs, qdict_get_str(qdict, "password"));
 665     if (err == -EINVAL) {
 666         qerror_report(QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
 667         return -1;
 668     } else if (err < 0) {
 669         qerror_report(QERR_INVALID_PASSWORD);
 670         return -1;
 671     }
 672
 673     return 0;
 674 }
 675
 676 int do_change_block(Monitor *mon, const char *device,
 677                     const char *filename, const char *fmt)
 678 {
 679     BlockDriverState *bs;
 680     BlockDriver *drv = NULL;
 681     int bdrv_flags;
 682
 683     bs = bdrv_find(device);
 684     if (!bs) {
 685         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 686         return -1;
 687     }
 688     if (fmt) {
 689         drv = bdrv_find_whitelisted_format(fmt);
 690         if (!drv) {
 691             qerror_report(QERR_INVALID_BLOCK_FORMAT, fmt);
 692             return -1;
 693         }
 694     }
 695     if (eject_device(mon, bs, 0) < 0) {
 696         return -1;
 697     }
 698     bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
 699     bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
 700     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
 701         qerror_report(QERR_OPEN_FILE_FAILED, filename);
 702         return -1;
 703     }
 704     return monitor_read_bdrv_key_start(mon, bs, NULL, NULL);
 705 }
 706
 707 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
 708 {
 709     const char *id = qdict_get_str(qdict, "id");
 710     BlockDriverState *bs;
 711     BlockDriverState **ptr;
 712     Property *prop;
 713
 714     bs = bdrv_find(id);
 715     if (!bs) {
 716         qerror_report(QERR_DEVICE_NOT_FOUND, id);
 717         return -1;
 718     }
 719
 720     /* quiesce block driver; prevent further io */
 721     qemu_aio_flush();
 722     bdrv_flush(bs);
 723     bdrv_close(bs);
 724
 725     /* clean up guest state from pointing to host resource by
 726      * finding and removing DeviceState "drive" property */
 727     if (bs->peer) {
 728         for (prop = bs->peer->info->props; prop && prop->name; prop++) {
 729             if (prop->info->type == PROP_TYPE_DRIVE) {
 730                 ptr = qdev_get_prop_ptr(bs->peer, prop);
 731                 if (*ptr == bs) {
 732                     bdrv_detach(bs, bs->peer);
 733                     *ptr = NULL;
 734                     break;
 735                 }
 736             }
 737         }
 738     }
 739
 740     /* clean up host side */
 741     drive_uninit(drive_get_by_blockdev(bs));
 742
 743     return 0;
 744 }
 745
 746 /*
 747  * XXX: replace the QERR_UNDEFINED_ERROR errors with real values once the
 748  * existing QERR_ macro mess is cleaned up.  A good example for better
 749  * error reports can be found in the qemu-img resize code.
 750  */
 751 int do_block_resize(Monitor *mon, const QDict *qdict, QObject **ret_data)
 752 {
 753     const char *device = qdict_get_str(qdict, "device");
 754     int64_t size = qdict_get_int(qdict, "size");
 755     BlockDriverState *bs;
 756
 757     bs = bdrv_find(device);
 758     if (!bs) {
 759         qerror_report(QERR_DEVICE_NOT_FOUND, device);
 760         return -1;
 761     }
 762
 763     if (size < 0) {
 764         qerror_report(QERR_UNDEFINED_ERROR);
 765         return -1;
 766     }
 767
 768     if (bdrv_truncate(bs, size)) {
 769         qerror_report(QERR_UNDEFINED_ERROR);
 770         return -1;
 771     }
 772
 773     return 0;
 774 }