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 "blockdev.h"
  11 #include "hw/block-common.h"
  12 #include "monitor.h"
  13 #include "qerror.h"
  14 #include "qemu-option.h"
  15 #include "qemu-config.h"
  16 #include "qemu-objects.h"
  17 #include "sysemu.h"
  18 #include "block_int.h"
  19 #include "qmp-commands.h"
  20 #include "trace.h"
  21 #include "arch_init.h"
  22
  23 static QTAILQ_HEAD(drivelist, DriveInfo) drives = QTAILQ_HEAD_INITIALIZER(drives);
  24
  25 static const char *const if_name[IF_COUNT] = {
  26     [IF_NONE] = "none",
  27     [IF_IDE] = "ide",
  28     [IF_SCSI] = "scsi",
  29     [IF_FLOPPY] = "floppy",
  30     [IF_PFLASH] = "pflash",
  31     [IF_MTD] = "mtd",
  32     [IF_SD] = "sd",
  33     [IF_VIRTIO] = "virtio",
  34     [IF_XEN] = "xen",
  35 };
  36
  37 static const int if_max_devs[IF_COUNT] = {
  38     /*
  39      * Do not change these numbers!  They govern how drive option
  40      * index maps to unit and bus.  That mapping is ABI.
  41      *
  42      * All controllers used to imlement if=T drives need to support
  43      * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
  44      * Otherwise, some index values map to "impossible" bus, unit
  45      * values.
  46      *
  47      * For instance, if you change [IF_SCSI] to 255, -drive
  48      * if=scsi,index=12 no longer means bus=1,unit=5, but
  49      * bus=0,unit=12.  With an lsi53c895a controller (7 units max),
  50      * the drive can't be set up.  Regression.
  51      */
  52     [IF_IDE] = 2,
  53     [IF_SCSI] = 7,
  54 };
  55
  56 /*
  57  * We automatically delete the drive when a device using it gets
  58  * unplugged.  Questionable feature, but we can't just drop it.
  59  * Device models call blockdev_mark_auto_del() to schedule the
  60  * automatic deletion, and generic qdev code calls blockdev_auto_del()
  61  * when deletion is actually safe.
  62  */
  63 void blockdev_mark_auto_del(BlockDriverState *bs)
  64 {
  65     DriveInfo *dinfo = drive_get_by_blockdev(bs);
  66
  67     if (bs->job) {
  68         block_job_cancel(bs->job);
  69     }
  70     if (dinfo) {
  71         dinfo->auto_del = 1;
  72     }
  73 }
  74
  75 void blockdev_auto_del(BlockDriverState *bs)
  76 {
  77     DriveInfo *dinfo = drive_get_by_blockdev(bs);
  78
  79     if (dinfo && dinfo->auto_del) {
  80         drive_put_ref(dinfo);
  81     }
  82 }
  83
  84 static int drive_index_to_bus_id(BlockInterfaceType type, int index)
  85 {
  86     int max_devs = if_max_devs[type];
  87     return max_devs ? index / max_devs : 0;
  88 }
  89
  90 static int drive_index_to_unit_id(BlockInterfaceType type, int index)
  91 {
  92     int max_devs = if_max_devs[type];
  93     return max_devs ? index % max_devs : index;
  94 }
  95
  96 QemuOpts *drive_def(const char *optstr)
  97 {
  98     return qemu_opts_parse(qemu_find_opts("drive"), optstr, 0);
  99 }
 100
 101 QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
 102                     const char *optstr)
 103 {
 104     QemuOpts *opts;
 105     char buf[32];
 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 DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
 140 {
 141     return drive_get(type,
 142                      drive_index_to_bus_id(type, index),
 143                      drive_index_to_unit_id(type, index));
 144 }
 145
 146 int drive_get_max_bus(BlockInterfaceType type)
 147 {
 148     int max_bus;
 149     DriveInfo *dinfo;
 150
 151     max_bus = -1;
 152     QTAILQ_FOREACH(dinfo, &drives, next) {
 153         if(dinfo->type == type &&
 154            dinfo->bus > max_bus)
 155             max_bus = dinfo->bus;
 156     }
 157     return max_bus;
 158 }
 159
 160 /* Get a block device.  This should only be used for single-drive devices
 161    (e.g. SD/Floppy/MTD).  Multi-disk devices (scsi/ide) should use the
 162    appropriate bus.  */
 163 DriveInfo *drive_get_next(BlockInterfaceType type)
 164 {
 165     static int next_block_unit[IF_COUNT];
 166
 167     return drive_get(type, 0, next_block_unit[type]++);
 168 }
 169
 170 DriveInfo *drive_get_by_blockdev(BlockDriverState *bs)
 171 {
 172     DriveInfo *dinfo;
 173
 174     QTAILQ_FOREACH(dinfo, &drives, next) {
 175         if (dinfo->bdrv == bs) {
 176             return dinfo;
 177         }
 178     }
 179     return NULL;
 180 }
 181
 182 static void bdrv_format_print(void *opaque, const char *name)
 183 {
 184     error_printf(" %s", name);
 185 }
 186
 187 static void drive_uninit(DriveInfo *dinfo)
 188 {
 189     qemu_opts_del(dinfo->opts);
 190     bdrv_delete(dinfo->bdrv);
 191     g_free(dinfo->id);
 192     QTAILQ_REMOVE(&drives, dinfo, next);
 193     g_free(dinfo);
 194 }
 195
 196 void drive_put_ref(DriveInfo *dinfo)
 197 {
 198     assert(dinfo->refcount);
 199     if (--dinfo->refcount == 0) {
 200         drive_uninit(dinfo);
 201     }
 202 }
 203
 204 void drive_get_ref(DriveInfo *dinfo)
 205 {
 206     dinfo->refcount++;
 207 }
 208
 209 typedef struct {
 210     QEMUBH *bh;
 211     DriveInfo *dinfo;
 212 } DrivePutRefBH;
 213
 214 static void drive_put_ref_bh(void *opaque)
 215 {
 216     DrivePutRefBH *s = opaque;
 217
 218     drive_put_ref(s->dinfo);
 219     qemu_bh_delete(s->bh);
 220     g_free(s);
 221 }
 222
 223 /*
 224  * Release a drive reference in a BH
 225  *
 226  * It is not possible to use drive_put_ref() from a callback function when the
 227  * callers still need the drive.  In such cases we schedule a BH to release the
 228  * reference.
 229  */
 230 static void drive_put_ref_bh_schedule(DriveInfo *dinfo)
 231 {
 232     DrivePutRefBH *s;
 233
 234     s = g_new(DrivePutRefBH, 1);
 235     s->bh = qemu_bh_new(drive_put_ref_bh, s);
 236     s->dinfo = dinfo;
 237     qemu_bh_schedule(s->bh);
 238 }
 239
 240 static int parse_block_error_action(const char *buf, int is_read)
 241 {
 242     if (!strcmp(buf, "ignore")) {
 243         return BLOCK_ERR_IGNORE;
 244     } else if (!is_read && !strcmp(buf, "enospc")) {
 245         return BLOCK_ERR_STOP_ENOSPC;
 246     } else if (!strcmp(buf, "stop")) {
 247         return BLOCK_ERR_STOP_ANY;
 248     } else if (!strcmp(buf, "report")) {
 249         return BLOCK_ERR_REPORT;
 250     } else {
 251         error_report("'%s' invalid %s error action",
 252                      buf, is_read ? "read" : "write");
 253         return -1;
 254     }
 255 }
 256
 257 static bool do_check_io_limits(BlockIOLimit *io_limits)
 258 {
 259     bool bps_flag;
 260     bool iops_flag;
 261
 262     assert(io_limits);
 263
 264     bps_flag  = (io_limits->bps[BLOCK_IO_LIMIT_TOTAL] != 0)
 265                  && ((io_limits->bps[BLOCK_IO_LIMIT_READ] != 0)
 266                  || (io_limits->bps[BLOCK_IO_LIMIT_WRITE] != 0));
 267     iops_flag = (io_limits->iops[BLOCK_IO_LIMIT_TOTAL] != 0)
 268                  && ((io_limits->iops[BLOCK_IO_LIMIT_READ] != 0)
 269                  || (io_limits->iops[BLOCK_IO_LIMIT_WRITE] != 0));
 270     if (bps_flag || iops_flag) {
 271         return false;
 272     }
 273
 274     return true;
 275 }
 276
 277 DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
 278 {
 279     const char *buf;
 280     const char *file = NULL;
 281     const char *serial;
 282     const char *mediastr = "";
 283     BlockInterfaceType type;
 284     enum { MEDIA_DISK, MEDIA_CDROM } media;
 285     int bus_id, unit_id;
 286     int cyls, heads, secs, translation;
 287     BlockDriver *drv = NULL;
 288     int max_devs;
 289     int index;
 290     int ro = 0;
 291     int bdrv_flags = 0;
 292     int on_read_error, on_write_error;
 293     const char *devaddr;
 294     DriveInfo *dinfo;
 295     BlockIOLimit io_limits;
 296     int snapshot = 0;
 297     bool copy_on_read;
 298     int ret;
 299
 300     translation = BIOS_ATA_TRANSLATION_AUTO;
 301     media = MEDIA_DISK;
 302
 303     /* extract parameters */
 304     bus_id  = qemu_opt_get_number(opts, "bus", 0);
 305     unit_id = qemu_opt_get_number(opts, "unit", -1);
 306     index   = qemu_opt_get_number(opts, "index", -1);
 307
 308     cyls  = qemu_opt_get_number(opts, "cyls", 0);
 309     heads = qemu_opt_get_number(opts, "heads", 0);
 310     secs  = qemu_opt_get_number(opts, "secs", 0);
 311
 312     snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
 313     ro = qemu_opt_get_bool(opts, "readonly", 0);
 314     copy_on_read = qemu_opt_get_bool(opts, "copy-on-read", false);
 315
 316     file = qemu_opt_get(opts, "file");
 317     serial = qemu_opt_get(opts, "serial");
 318
 319     if ((buf = qemu_opt_get(opts, "if")) != NULL) {
 320         for (type = 0; type < IF_COUNT && strcmp(buf, if_name[type]); type++)
 321             ;
 322         if (type == IF_COUNT) {
 323             error_report("unsupported bus type '%s'", buf);
 324             return NULL;
 325         }
 326     } else {
 327         type = default_to_scsi ? IF_SCSI : IF_IDE;
 328     }
 329
 330     max_devs = if_max_devs[type];
 331
 332     if (cyls || heads || secs) {
 333         if (cyls < 1) {
 334             error_report("invalid physical cyls number");
 335             return NULL;
 336         }
 337         if (heads < 1) {
 338             error_report("invalid physical heads number");
 339             return NULL;
 340         }
 341         if (secs < 1) {
 342             error_report("invalid physical secs number");
 343             return NULL;
 344         }
 345     }
 346
 347     if ((buf = qemu_opt_get(opts, "trans")) != NULL) {
 348         if (!cyls) {
 349             error_report("'%s' trans must be used with cyls, heads and secs",
 350                          buf);
 351             return NULL;
 352         }
 353         if (!strcmp(buf, "none"))
 354             translation = BIOS_ATA_TRANSLATION_NONE;
 355         else if (!strcmp(buf, "lba"))
 356             translation = BIOS_ATA_TRANSLATION_LBA;
 357         else if (!strcmp(buf, "auto"))
 358             translation = BIOS_ATA_TRANSLATION_AUTO;
 359         else {
 360             error_report("'%s' invalid translation type", buf);
 361             return NULL;
 362         }
 363     }
 364
 365     if ((buf = qemu_opt_get(opts, "media")) != NULL) {
 366         if (!strcmp(buf, "disk")) {
 367             media = MEDIA_DISK;
 368         } else if (!strcmp(buf, "cdrom")) {
 369             if (cyls || secs || heads) {
 370                 error_report("CHS can't be set with media=%s", buf);
 371                 return NULL;
 372             }
 373             media = MEDIA_CDROM;
 374         } else {
 375             error_report("'%s' invalid media", buf);
 376             return NULL;
 377         }
 378     }
 379
 380     if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
 381         if (bdrv_parse_cache_flags(buf, &bdrv_flags) != 0) {
 382             error_report("invalid cache option");
 383             return NULL;
 384         }
 385     }
 386
 387 #ifdef CONFIG_LINUX_AIO
 388     if ((buf = qemu_opt_get(opts, "aio")) != NULL) {
 389         if (!strcmp(buf, "native")) {
 390             bdrv_flags |= BDRV_O_NATIVE_AIO;
 391         } else if (!strcmp(buf, "threads")) {
 392             /* this is the default */
 393         } else {
 394            error_report("invalid aio option");
 395            return NULL;
 396         }
 397     }
 398 #endif
 399
 400     if ((buf = qemu_opt_get(opts, "format")) != NULL) {
 401        if (strcmp(buf, "?") == 0) {
 402            error_printf("Supported formats:");
 403            bdrv_iterate_format(bdrv_format_print, NULL);
 404            error_printf("\n");
 405            return NULL;
 406         }
 407         drv = bdrv_find_whitelisted_format(buf);
 408         if (!drv) {
 409             error_report("'%s' invalid format", buf);
 410             return NULL;
 411         }
 412     }
 413
 414     /* disk I/O throttling */
 415     io_limits.bps[BLOCK_IO_LIMIT_TOTAL]  =
 416                            qemu_opt_get_number(opts, "bps", 0);
 417     io_limits.bps[BLOCK_IO_LIMIT_READ]   =
 418                            qemu_opt_get_number(opts, "bps_rd", 0);
 419     io_limits.bps[BLOCK_IO_LIMIT_WRITE]  =
 420                            qemu_opt_get_number(opts, "bps_wr", 0);
 421     io_limits.iops[BLOCK_IO_LIMIT_TOTAL] =
 422                            qemu_opt_get_number(opts, "iops", 0);
 423     io_limits.iops[BLOCK_IO_LIMIT_READ]  =
 424                            qemu_opt_get_number(opts, "iops_rd", 0);
 425     io_limits.iops[BLOCK_IO_LIMIT_WRITE] =
 426                            qemu_opt_get_number(opts, "iops_wr", 0);
 427
 428     if (!do_check_io_limits(&io_limits)) {
 429         error_report("bps(iops) and bps_rd/bps_wr(iops_rd/iops_wr) "
 430                      "cannot be used at the same time");
 431         return NULL;
 432     }
 433
 434     on_write_error = BLOCK_ERR_STOP_ENOSPC;
 435     if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
 436         if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO && type != IF_NONE) {
 437             error_report("werror is not supported by this bus type");
 438             return NULL;
 439         }
 440
 441         on_write_error = parse_block_error_action(buf, 0);
 442         if (on_write_error < 0) {
 443             return NULL;
 444         }
 445     }
 446
 447     on_read_error = BLOCK_ERR_REPORT;
 448     if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
 449         if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI && type != IF_NONE) {
 450             error_report("rerror is not supported by this bus type");
 451             return NULL;
 452         }
 453
 454         on_read_error = parse_block_error_action(buf, 1);
 455         if (on_read_error < 0) {
 456             return NULL;
 457         }
 458     }
 459
 460     if ((devaddr = qemu_opt_get(opts, "addr")) != NULL) {
 461         if (type != IF_VIRTIO) {
 462             error_report("addr is not supported by this bus type");
 463             return NULL;
 464         }
 465     }
 466
 467     /* compute bus and unit according index */
 468
 469     if (index != -1) {
 470         if (bus_id != 0 || unit_id != -1) {
 471             error_report("index cannot be used with bus and unit");
 472             return NULL;
 473         }
 474         bus_id = drive_index_to_bus_id(type, index);
 475         unit_id = drive_index_to_unit_id(type, index);
 476     }
 477
 478     /* if user doesn't specify a unit_id,
 479      * try to find the first free
 480      */
 481
 482     if (unit_id == -1) {
 483        unit_id = 0;
 484        while (drive_get(type, bus_id, unit_id) != NULL) {
 485            unit_id++;
 486            if (max_devs && unit_id >= max_devs) {
 487                unit_id -= max_devs;
 488                bus_id++;
 489            }
 490        }
 491     }
 492
 493     /* check unit id */
 494
 495     if (max_devs && unit_id >= max_devs) {
 496         error_report("unit %d too big (max is %d)",
 497                      unit_id, max_devs - 1);
 498         return NULL;
 499     }
 500
 501     /*
 502      * catch multiple definitions
 503      */
 504
 505     if (drive_get(type, bus_id, unit_id) != NULL) {
 506         error_report("drive with bus=%d, unit=%d (index=%d) exists",
 507                      bus_id, unit_id, index);
 508         return NULL;
 509     }
 510
 511     /* init */
 512
 513     dinfo = g_malloc0(sizeof(*dinfo));
 514     if ((buf = qemu_opts_id(opts)) != NULL) {
 515         dinfo->id = g_strdup(buf);
 516     } else {
 517         /* no id supplied -> create one */
 518         dinfo->id = g_malloc0(32);
 519         if (type == IF_IDE || type == IF_SCSI)
 520             mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
 521         if (max_devs)
 522             snprintf(dinfo->id, 32, "%s%i%s%i",
 523                      if_name[type], bus_id, mediastr, unit_id);
 524         else
 525             snprintf(dinfo->id, 32, "%s%s%i",
 526                      if_name[type], mediastr, unit_id);
 527     }
 528     dinfo->bdrv = bdrv_new(dinfo->id);
 529     dinfo->devaddr = devaddr;
 530     dinfo->type = type;
 531     dinfo->bus = bus_id;
 532     dinfo->unit = unit_id;
 533     dinfo->cyls = cyls;
 534     dinfo->heads = heads;
 535     dinfo->secs = secs;
 536     dinfo->trans = translation;
 537     dinfo->opts = opts;
 538     dinfo->refcount = 1;
 539     if (serial) {
 540         pstrcpy(dinfo->serial, sizeof(dinfo->serial), serial);
 541     }
 542     QTAILQ_INSERT_TAIL(&drives, dinfo, next);
 543
 544     bdrv_set_on_error(dinfo->bdrv, on_read_error, on_write_error);
 545
 546     /* disk I/O throttling */
 547     bdrv_set_io_limits(dinfo->bdrv, &io_limits);
 548
 549     switch(type) {
 550     case IF_IDE:
 551     case IF_SCSI:
 552     case IF_XEN:
 553     case IF_NONE:
 554         dinfo->media_cd = media == MEDIA_CDROM;
 555         break;
 556     case IF_SD:
 557     case IF_FLOPPY:
 558     case IF_PFLASH:
 559     case IF_MTD:
 560         break;
 561     case IF_VIRTIO:
 562         /* add virtio block device */
 563         opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0, NULL);
 564         if (arch_type == QEMU_ARCH_S390X) {
 565             qemu_opt_set(opts, "driver", "virtio-blk-s390");
 566         } else {
 567             qemu_opt_set(opts, "driver", "virtio-blk-pci");
 568         }
 569         qemu_opt_set(opts, "drive", dinfo->id);
 570         if (devaddr)
 571             qemu_opt_set(opts, "addr", devaddr);
 572         break;
 573     default:
 574         abort();
 575     }
 576     if (!file || !*file) {
 577         return dinfo;
 578     }
 579     if (snapshot) {
 580         /* always use cache=unsafe with snapshot */
 581         bdrv_flags &= ~BDRV_O_CACHE_MASK;
 582         bdrv_flags |= (BDRV_O_SNAPSHOT|BDRV_O_CACHE_WB|BDRV_O_NO_FLUSH);
 583     }
 584
 585     if (copy_on_read) {
 586         bdrv_flags |= BDRV_O_COPY_ON_READ;
 587     }
 588
 589     if (runstate_check(RUN_STATE_INMIGRATE)) {
 590         bdrv_flags |= BDRV_O_INCOMING;
 591     }
 592
 593     if (media == MEDIA_CDROM) {
 594         /* CDROM is fine for any interface, don't check.  */
 595         ro = 1;
 596     } else if (ro == 1) {
 597         if (type != IF_SCSI && type != IF_VIRTIO && type != IF_FLOPPY &&
 598             type != IF_NONE && type != IF_PFLASH) {
 599             error_report("readonly not supported by this bus type");
 600             goto err;
 601         }
 602     }
 603
 604     bdrv_flags |= ro ? 0 : BDRV_O_RDWR;
 605
 606     if (ro && copy_on_read) {
 607         error_report("warning: disabling copy_on_read on readonly drive");
 608     }
 609
 610     ret = bdrv_open(dinfo->bdrv, file, bdrv_flags, drv);
 611     if (ret < 0) {
 612         error_report("could not open disk image %s: %s",
 613                      file, strerror(-ret));
 614         goto err;
 615     }
 616
 617     if (bdrv_key_required(dinfo->bdrv))
 618         autostart = 0;
 619     return dinfo;
 620
 621 err:
 622     bdrv_delete(dinfo->bdrv);
 623     g_free(dinfo->id);
 624     QTAILQ_REMOVE(&drives, dinfo, next);
 625     g_free(dinfo);
 626     return NULL;
 627 }
 628
 629 void do_commit(Monitor *mon, const QDict *qdict)
 630 {
 631     const char *device = qdict_get_str(qdict, "device");
 632     BlockDriverState *bs;
 633     int ret;
 634
 635     if (!strcmp(device, "all")) {
 636         ret = bdrv_commit_all();
 637         if (ret == -EBUSY) {
 638             qerror_report(QERR_DEVICE_IN_USE, device);
 639             return;
 640         }
 641     } else {
 642         bs = bdrv_find(device);
 643         if (!bs) {
 644             qerror_report(QERR_DEVICE_NOT_FOUND, device);
 645             return;
 646         }
 647         ret = bdrv_commit(bs);
 648         if (ret == -EBUSY) {
 649             qerror_report(QERR_DEVICE_IN_USE, device);
 650             return;
 651         }
 652     }
 653 }
 654
 655 static void blockdev_do_action(int kind, void *data, Error **errp)
 656 {
 657     BlockdevAction action;
 658     BlockdevActionList list;
 659
 660     action.kind = kind;
 661     action.data = data;
 662     list.value = &action;
 663     list.next = NULL;
 664     qmp_transaction(&list, errp);
 665 }
 666
 667 void qmp_blockdev_snapshot_sync(const char *device, const char *snapshot_file,
 668                                 bool has_format, const char *format,
 669                                 bool has_mode, enum NewImageMode mode,
 670                                 Error **errp)
 671 {
 672     BlockdevSnapshot snapshot = {
 673         .device = (char *) device,
 674         .snapshot_file = (char *) snapshot_file,
 675         .has_format = has_format,
 676         .format = (char *) format,
 677         .has_mode = has_mode,
 678         .mode = mode,
 679     };
 680     blockdev_do_action(BLOCKDEV_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC, &snapshot,
 681                        errp);
 682 }
 683
 684
 685 /* New and old BlockDriverState structs for group snapshots */
 686 typedef struct BlkTransactionStates {
 687     BlockDriverState *old_bs;
 688     BlockDriverState *new_bs;
 689     QSIMPLEQ_ENTRY(BlkTransactionStates) entry;
 690 } BlkTransactionStates;
 691
 692 /*
 693  * 'Atomic' group snapshots.  The snapshots are taken as a set, and if any fail
 694  *  then we do not pivot any of the devices in the group, and abandon the
 695  *  snapshots
 696  */
 697 void qmp_transaction(BlockdevActionList *dev_list, Error **errp)
 698 {
 699     int ret = 0;
 700     BlockdevActionList *dev_entry = dev_list;
 701     BlkTransactionStates *states, *next;
 702
 703     QSIMPLEQ_HEAD(snap_bdrv_states, BlkTransactionStates) snap_bdrv_states;
 704     QSIMPLEQ_INIT(&snap_bdrv_states);
 705
 706     /* drain all i/o before any snapshots */
 707     bdrv_drain_all();
 708
 709     /* We don't do anything in this loop that commits us to the snapshot */
 710     while (NULL != dev_entry) {
 711         BlockdevAction *dev_info = NULL;
 712         BlockDriver *proto_drv;
 713         BlockDriver *drv;
 714         int flags;
 715         enum NewImageMode mode;
 716         const char *new_image_file;
 717         const char *device;
 718         const char *format = "qcow2";
 719
 720         dev_info = dev_entry->value;
 721         dev_entry = dev_entry->next;
 722
 723         states = g_malloc0(sizeof(BlkTransactionStates));
 724         QSIMPLEQ_INSERT_TAIL(&snap_bdrv_states, states, entry);
 725
 726         switch (dev_info->kind) {
 727         case BLOCKDEV_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
 728             device = dev_info->blockdev_snapshot_sync->device;
 729             if (!dev_info->blockdev_snapshot_sync->has_mode) {
 730                 dev_info->blockdev_snapshot_sync->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
 731             }
 732             new_image_file = dev_info->blockdev_snapshot_sync->snapshot_file;
 733             if (dev_info->blockdev_snapshot_sync->has_format) {
 734                 format = dev_info->blockdev_snapshot_sync->format;
 735             }
 736             mode = dev_info->blockdev_snapshot_sync->mode;
 737             break;
 738         default:
 739             abort();
 740         }
 741
 742         drv = bdrv_find_format(format);
 743         if (!drv) {
 744             error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
 745             goto delete_and_fail;
 746         }
 747
 748         states->old_bs = bdrv_find(device);
 749         if (!states->old_bs) {
 750             error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 751             goto delete_and_fail;
 752         }
 753
 754         if (!bdrv_is_inserted(states->old_bs)) {
 755             error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
 756             goto delete_and_fail;
 757         }
 758
 759         if (bdrv_in_use(states->old_bs)) {
 760             error_set(errp, QERR_DEVICE_IN_USE, device);
 761             goto delete_and_fail;
 762         }
 763
 764         if (!bdrv_is_read_only(states->old_bs)) {
 765             if (bdrv_flush(states->old_bs)) {
 766                 error_set(errp, QERR_IO_ERROR);
 767                 goto delete_and_fail;
 768             }
 769         }
 770
 771         flags = states->old_bs->open_flags;
 772
 773         proto_drv = bdrv_find_protocol(new_image_file);
 774         if (!proto_drv) {
 775             error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
 776             goto delete_and_fail;
 777         }
 778
 779         /* create new image w/backing file */
 780         if (mode != NEW_IMAGE_MODE_EXISTING) {
 781             ret = bdrv_img_create(new_image_file, format,
 782                                   states->old_bs->filename,
 783                                   states->old_bs->drv->format_name,
 784                                   NULL, -1, flags);
 785             if (ret) {
 786                 error_set(errp, QERR_OPEN_FILE_FAILED, new_image_file);
 787                 goto delete_and_fail;
 788             }
 789         }
 790
 791         /* We will manually add the backing_hd field to the bs later */
 792         states->new_bs = bdrv_new("");
 793         ret = bdrv_open(states->new_bs, new_image_file,
 794                         flags | BDRV_O_NO_BACKING, drv);
 795         if (ret != 0) {
 796             error_set(errp, QERR_OPEN_FILE_FAILED, new_image_file);
 797             goto delete_and_fail;
 798         }
 799     }
 800
 801
 802     /* Now we are going to do the actual pivot.  Everything up to this point
 803      * is reversible, but we are committed at this point */
 804     QSIMPLEQ_FOREACH(states, &snap_bdrv_states, entry) {
 805         /* This removes our old bs from the bdrv_states, and adds the new bs */
 806         bdrv_append(states->new_bs, states->old_bs);
 807     }
 808
 809     /* success */
 810     goto exit;
 811
 812 delete_and_fail:
 813     /*
 814     * failure, and it is all-or-none; abandon each new bs, and keep using
 815     * the original bs for all images
 816     */
 817     QSIMPLEQ_FOREACH(states, &snap_bdrv_states, entry) {
 818         if (states->new_bs) {
 819              bdrv_delete(states->new_bs);
 820         }
 821     }
 822 exit:
 823     QSIMPLEQ_FOREACH_SAFE(states, &snap_bdrv_states, entry, next) {
 824         g_free(states);
 825     }
 826     return;
 827 }
 828
 829
 830 static void eject_device(BlockDriverState *bs, int force, Error **errp)
 831 {
 832     if (bdrv_in_use(bs)) {
 833         error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
 834         return;
 835     }
 836     if (!bdrv_dev_has_removable_media(bs)) {
 837         error_set(errp, QERR_DEVICE_NOT_REMOVABLE, bdrv_get_device_name(bs));
 838         return;
 839     }
 840
 841     if (bdrv_dev_is_medium_locked(bs) && !bdrv_dev_is_tray_open(bs)) {
 842         bdrv_dev_eject_request(bs, force);
 843         if (!force) {
 844             error_set(errp, QERR_DEVICE_LOCKED, bdrv_get_device_name(bs));
 845             return;
 846         }
 847     }
 848
 849     bdrv_close(bs);
 850 }
 851
 852 void qmp_eject(const char *device, bool has_force, bool force, Error **errp)
 853 {
 854     BlockDriverState *bs;
 855
 856     bs = bdrv_find(device);
 857     if (!bs) {
 858         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 859         return;
 860     }
 861
 862     eject_device(bs, force, errp);
 863 }
 864
 865 void qmp_block_passwd(const char *device, const char *password, Error **errp)
 866 {
 867     BlockDriverState *bs;
 868     int err;
 869
 870     bs = bdrv_find(device);
 871     if (!bs) {
 872         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 873         return;
 874     }
 875
 876     err = bdrv_set_key(bs, password);
 877     if (err == -EINVAL) {
 878         error_set(errp, QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
 879         return;
 880     } else if (err < 0) {
 881         error_set(errp, QERR_INVALID_PASSWORD);
 882         return;
 883     }
 884 }
 885
 886 static void qmp_bdrv_open_encrypted(BlockDriverState *bs, const char *filename,
 887                                     int bdrv_flags, BlockDriver *drv,
 888                                     const char *password, Error **errp)
 889 {
 890     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
 891         error_set(errp, QERR_OPEN_FILE_FAILED, filename);
 892         return;
 893     }
 894
 895     if (bdrv_key_required(bs)) {
 896         if (password) {
 897             if (bdrv_set_key(bs, password) < 0) {
 898                 error_set(errp, QERR_INVALID_PASSWORD);
 899             }
 900         } else {
 901             error_set(errp, QERR_DEVICE_ENCRYPTED, bdrv_get_device_name(bs),
 902                       bdrv_get_encrypted_filename(bs));
 903         }
 904     } else if (password) {
 905         error_set(errp, QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
 906     }
 907 }
 908
 909 void qmp_change_blockdev(const char *device, const char *filename,
 910                          bool has_format, const char *format, Error **errp)
 911 {
 912     BlockDriverState *bs;
 913     BlockDriver *drv = NULL;
 914     int bdrv_flags;
 915     Error *err = NULL;
 916
 917     bs = bdrv_find(device);
 918     if (!bs) {
 919         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 920         return;
 921     }
 922
 923     if (format) {
 924         drv = bdrv_find_whitelisted_format(format);
 925         if (!drv) {
 926             error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
 927             return;
 928         }
 929     }
 930
 931     eject_device(bs, 0, &err);
 932     if (error_is_set(&err)) {
 933         error_propagate(errp, err);
 934         return;
 935     }
 936
 937     bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
 938     bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
 939
 940     qmp_bdrv_open_encrypted(bs, filename, bdrv_flags, drv, NULL, errp);
 941 }
 942
 943 /* throttling disk I/O limits */
 944 void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd,
 945                                int64_t bps_wr, int64_t iops, int64_t iops_rd,
 946                                int64_t iops_wr, Error **errp)
 947 {
 948     BlockIOLimit io_limits;
 949     BlockDriverState *bs;
 950
 951     bs = bdrv_find(device);
 952     if (!bs) {
 953         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
 954         return;
 955     }
 956
 957     io_limits.bps[BLOCK_IO_LIMIT_TOTAL] = bps;
 958     io_limits.bps[BLOCK_IO_LIMIT_READ]  = bps_rd;
 959     io_limits.bps[BLOCK_IO_LIMIT_WRITE] = bps_wr;
 960     io_limits.iops[BLOCK_IO_LIMIT_TOTAL]= iops;
 961     io_limits.iops[BLOCK_IO_LIMIT_READ] = iops_rd;
 962     io_limits.iops[BLOCK_IO_LIMIT_WRITE]= iops_wr;
 963
 964     if (!do_check_io_limits(&io_limits)) {
 965         error_set(errp, QERR_INVALID_PARAMETER_COMBINATION);
 966         return;
 967     }
 968
 969     bs->io_limits = io_limits;
 970     bs->slice_time = BLOCK_IO_SLICE_TIME;
 971
 972     if (!bs->io_limits_enabled && bdrv_io_limits_enabled(bs)) {
 973         bdrv_io_limits_enable(bs);
 974     } else if (bs->io_limits_enabled && !bdrv_io_limits_enabled(bs)) {
 975         bdrv_io_limits_disable(bs);
 976     } else {
 977         if (bs->block_timer) {
 978             qemu_mod_timer(bs->block_timer, qemu_get_clock_ns(vm_clock));
 979         }
 980     }
 981 }
 982
 983 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
 984 {
 985     const char *id = qdict_get_str(qdict, "id");
 986     BlockDriverState *bs;
 987
 988     bs = bdrv_find(id);
 989     if (!bs) {
 990         qerror_report(QERR_DEVICE_NOT_FOUND, id);
 991         return -1;
 992     }
 993     if (bdrv_in_use(bs)) {
 994         qerror_report(QERR_DEVICE_IN_USE, id);
 995         return -1;
 996     }
 997
 998     /* quiesce block driver; prevent further io */
 999     bdrv_drain_all();
1000     bdrv_flush(bs);
1001     bdrv_close(bs);
1002
1003     /* if we have a device attached to this BlockDriverState
1004      * then we need to make the drive anonymous until the device
1005      * can be removed.  If this is a drive with no device backing
1006      * then we can just get rid of the block driver state right here.
1007      */
1008     if (bdrv_get_attached_dev(bs)) {
1009         bdrv_make_anon(bs);
1010     } else {
1011         drive_uninit(drive_get_by_blockdev(bs));
1012     }
1013
1014     return 0;
1015 }
1016
1017 void qmp_block_resize(const char *device, int64_t size, Error **errp)
1018 {
1019     BlockDriverState *bs;
1020
1021     bs = bdrv_find(device);
1022     if (!bs) {
1023         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
1024         return;
1025     }
1026
1027     if (size < 0) {
1028         error_set(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
1029         return;
1030     }
1031
1032     switch (bdrv_truncate(bs, size)) {
1033     case 0:
1034         break;
1035     case -ENOMEDIUM:
1036         error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
1037         break;
1038     case -ENOTSUP:
1039         error_set(errp, QERR_UNSUPPORTED);
1040         break;
1041     case -EACCES:
1042         error_set(errp, QERR_DEVICE_IS_READ_ONLY, device);
1043         break;
1044     case -EBUSY:
1045         error_set(errp, QERR_DEVICE_IN_USE, device);
1046         break;
1047     default:
1048         error_set(errp, QERR_UNDEFINED_ERROR);
1049         break;
1050     }
1051 }
1052
1053 static QObject *qobject_from_block_job(BlockJob *job)
1054 {
1055     return qobject_from_jsonf("{ 'type': %s,"
1056                               "'device': %s,"
1057                               "'len': %" PRId64 ","
1058                               "'offset': %" PRId64 ","
1059                               "'speed': %" PRId64 " }",
1060                               job->job_type->job_type,
1061                               bdrv_get_device_name(job->bs),
1062                               job->len,
1063                               job->offset,
1064                               job->speed);
1065 }
1066
1067 static void block_stream_cb(void *opaque, int ret)
1068 {
1069     BlockDriverState *bs = opaque;
1070     QObject *obj;
1071
1072     trace_block_stream_cb(bs, bs->job, ret);
1073
1074     assert(bs->job);
1075     obj = qobject_from_block_job(bs->job);
1076     if (ret < 0) {
1077         QDict *dict = qobject_to_qdict(obj);
1078         qdict_put(dict, "error", qstring_from_str(strerror(-ret)));
1079     }
1080
1081     if (block_job_is_cancelled(bs->job)) {
1082         monitor_protocol_event(QEVENT_BLOCK_JOB_CANCELLED, obj);
1083     } else {
1084         monitor_protocol_event(QEVENT_BLOCK_JOB_COMPLETED, obj);
1085     }
1086     qobject_decref(obj);
1087
1088     drive_put_ref_bh_schedule(drive_get_by_blockdev(bs));
1089 }
1090
1091 void qmp_block_stream(const char *device, bool has_base,
1092                       const char *base, bool has_speed,
1093                       int64_t speed, Error **errp)
1094 {
1095     BlockDriverState *bs;
1096     BlockDriverState *base_bs = NULL;
1097     Error *local_err = NULL;
1098
1099     bs = bdrv_find(device);
1100     if (!bs) {
1101         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
1102         return;
1103     }
1104
1105     if (base) {
1106         base_bs = bdrv_find_backing_image(bs, base);
1107         if (base_bs == NULL) {
1108             error_set(errp, QERR_BASE_NOT_FOUND, base);
1109             return;
1110         }
1111     }
1112
1113     stream_start(bs, base_bs, base, has_speed ? speed : 0,
1114                  block_stream_cb, bs, &local_err);
1115     if (error_is_set(&local_err)) {
1116         error_propagate(errp, local_err);
1117         return;
1118     }
1119
1120     /* Grab a reference so hotplug does not delete the BlockDriverState from
1121      * underneath us.
1122      */
1123     drive_get_ref(drive_get_by_blockdev(bs));
1124
1125     trace_qmp_block_stream(bs, bs->job);
1126 }
1127
1128 static BlockJob *find_block_job(const char *device)
1129 {
1130     BlockDriverState *bs;
1131
1132     bs = bdrv_find(device);
1133     if (!bs || !bs->job) {
1134         return NULL;
1135     }
1136     return bs->job;
1137 }
1138
1139 void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
1140 {
1141     BlockJob *job = find_block_job(device);
1142
1143     if (!job) {
1144         error_set(errp, QERR_DEVICE_NOT_ACTIVE, device);
1145         return;
1146     }
1147
1148     block_job_set_speed(job, speed, errp);
1149 }
1150
1151 void qmp_block_job_cancel(const char *device, Error **errp)
1152 {
1153     BlockJob *job = find_block_job(device);
1154
1155     if (!job) {
1156         error_set(errp, QERR_DEVICE_NOT_ACTIVE, device);
1157         return;
1158     }
1159
1160     trace_qmp_block_job_cancel(job);
1161     block_job_cancel(job);
1162 }
1163
1164 static void do_qmp_query_block_jobs_one(void *opaque, BlockDriverState *bs)
1165 {
1166     BlockJobInfoList **prev = opaque;
1167     BlockJob *job = bs->job;
1168
1169     if (job) {
1170         BlockJobInfoList *elem;
1171         BlockJobInfo *info = g_new(BlockJobInfo, 1);
1172         *info = (BlockJobInfo){
1173             .type   = g_strdup(job->job_type->job_type),
1174             .device = g_strdup(bdrv_get_device_name(bs)),
1175             .len    = job->len,
1176             .offset = job->offset,
1177             .speed  = job->speed,
1178         };
1179
1180         elem = g_new0(BlockJobInfoList, 1);
1181         elem->value = info;
1182
1183         (*prev)->next = elem;
1184         *prev = elem;
1185     }
1186 }
1187
1188 BlockJobInfoList *qmp_query_block_jobs(Error **errp)
1189 {
1190     /* Dummy is a fake list element for holding the head pointer */
1191     BlockJobInfoList dummy = {};
1192     BlockJobInfoList *prev = &dummy;
1193     bdrv_iterate(do_qmp_query_block_jobs_one, &prev);
1194     return dummy.next;
1195 }