block/parallels.c

   1 /*
   2  * Block driver for Parallels disk image format
   3  *
   4  * Copyright (c) 2007 Alex Beregszaszi
   5  * Copyright (c) 2015 Denis V. Lunev <den@openvz.org>
   6  *
   7  * This code was originally based on comparing different disk images created
   8  * by Parallels. Currently it is based on opened OpenVZ sources
   9  * available at
  10  *     http://git.openvz.org/?p=ploop;a=summary
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a copy
  13  * of this software and associated documentation files (the "Software"), to deal
  14  * in the Software without restriction, including without limitation the rights
  15  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  16  * copies of the Software, and to permit persons to whom the Software is
  17  * furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included in
  20  * all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  25  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  26  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  27  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  28  * THE SOFTWARE.
  29  */
  30 #include "qemu/osdep.h"
  31 #include "qapi/error.h"
  32 #include "qemu-common.h"
  33 #include "block/block_int.h"
  34 #include "sysemu/block-backend.h"
  35 #include "qemu/module.h"
  36 #include "qemu/bswap.h"
  37 #include "qemu/bitmap.h"
  38 #include "qapi/util.h"
  39
  40 /**************************************************************/
  41
  42 #define HEADER_MAGIC "WithoutFreeSpace"
  43 #define HEADER_MAGIC2 "WithouFreSpacExt"
  44 #define HEADER_VERSION 2
  45 #define HEADER_INUSE_MAGIC  (0x746F6E59)
  46 #define MAX_PARALLELS_IMAGE_FACTOR (1ull << 32)
  47
  48 #define DEFAULT_CLUSTER_SIZE 1048576        /* 1 MiB */
  49
  50
  51 // always little-endian
  52 typedef struct ParallelsHeader {
  53     char magic[16]; // "WithoutFreeSpace"
  54     uint32_t version;
  55     uint32_t heads;
  56     uint32_t cylinders;
  57     uint32_t tracks;
  58     uint32_t bat_entries;
  59     uint64_t nb_sectors;
  60     uint32_t inuse;
  61     uint32_t data_off;
  62     char padding[12];
  63 } QEMU_PACKED ParallelsHeader;
  64
  65
  66 typedef enum ParallelsPreallocMode {
  67     PRL_PREALLOC_MODE_FALLOCATE = 0,
  68     PRL_PREALLOC_MODE_TRUNCATE = 1,
  69     PRL_PREALLOC_MODE__MAX = 2,
  70 } ParallelsPreallocMode;
  71
  72 static const char *prealloc_mode_lookup[] = {
  73     "falloc",
  74     "truncate",
  75     NULL,
  76 };
  77
  78
  79 typedef struct BDRVParallelsState {
  80     /** Locking is conservative, the lock protects
  81      *   - image file extending (truncate, fallocate)
  82      *   - any access to block allocation table
  83      */
  84     CoMutex lock;
  85
  86     ParallelsHeader *header;
  87     uint32_t header_size;
  88     bool header_unclean;
  89
  90     unsigned long *bat_dirty_bmap;
  91     unsigned int  bat_dirty_block;
  92
  93     uint32_t *bat_bitmap;
  94     unsigned int bat_size;
  95
  96     int64_t  data_end;
  97     uint64_t prealloc_size;
  98     ParallelsPreallocMode prealloc_mode;
  99
 100     unsigned int tracks;
 101
 102     unsigned int off_multiplier;
 103 } BDRVParallelsState;
 104
 105
 106 #define PARALLELS_OPT_PREALLOC_MODE     "prealloc-mode"
 107 #define PARALLELS_OPT_PREALLOC_SIZE     "prealloc-size"
 108
 109 static QemuOptsList parallels_runtime_opts = {
 110     .name = "parallels",
 111     .head = QTAILQ_HEAD_INITIALIZER(parallels_runtime_opts.head),
 112     .desc = {
 113         {
 114             .name = PARALLELS_OPT_PREALLOC_SIZE,
 115             .type = QEMU_OPT_SIZE,
 116             .help = "Preallocation size on image expansion",
 117             .def_value_str = "128MiB",
 118         },
 119         {
 120             .name = PARALLELS_OPT_PREALLOC_MODE,
 121             .type = QEMU_OPT_STRING,
 122             .help = "Preallocation mode on image expansion "
 123                     "(allowed values: falloc, truncate)",
 124             .def_value_str = "falloc",
 125         },
 126         { /* end of list */ },
 127     },
 128 };
 129
 130
 131 static int64_t bat2sect(BDRVParallelsState *s, uint32_t idx)
 132 {
 133     return (uint64_t)le32_to_cpu(s->bat_bitmap[idx]) * s->off_multiplier;
 134 }
 135
 136 static uint32_t bat_entry_off(uint32_t idx)
 137 {
 138     return sizeof(ParallelsHeader) + sizeof(uint32_t) * idx;
 139 }
 140
 141 static int64_t seek_to_sector(BDRVParallelsState *s, int64_t sector_num)
 142 {
 143     uint32_t index, offset;
 144
 145     index = sector_num / s->tracks;
 146     offset = sector_num % s->tracks;
 147
 148     /* not allocated */
 149     if ((index >= s->bat_size) || (s->bat_bitmap[index] == 0)) {
 150         return -1;
 151     }
 152     return bat2sect(s, index) + offset;
 153 }
 154
 155 static int cluster_remainder(BDRVParallelsState *s, int64_t sector_num,
 156         int nb_sectors)
 157 {
 158     int ret = s->tracks - sector_num % s->tracks;
 159     return MIN(nb_sectors, ret);
 160 }
 161
 162 static int64_t block_status(BDRVParallelsState *s, int64_t sector_num,
 163                             int nb_sectors, int *pnum)
 164 {
 165     int64_t start_off = -2, prev_end_off = -2;
 166
 167     *pnum = 0;
 168     while (nb_sectors > 0 || start_off == -2) {
 169         int64_t offset = seek_to_sector(s, sector_num);
 170         int to_end;
 171
 172         if (start_off == -2) {
 173             start_off = offset;
 174             prev_end_off = offset;
 175         } else if (offset != prev_end_off) {
 176             break;
 177         }
 178
 179         to_end = cluster_remainder(s, sector_num, nb_sectors);
 180         nb_sectors -= to_end;
 181         sector_num += to_end;
 182         *pnum += to_end;
 183
 184         if (offset > 0) {
 185             prev_end_off += to_end;
 186         }
 187     }
 188     return start_off;
 189 }
 190
 191 static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num,
 192                                  int nb_sectors, int *pnum)
 193 {
 194     BDRVParallelsState *s = bs->opaque;
 195     uint32_t idx, to_allocate, i;
 196     int64_t pos, space;
 197
 198     pos = block_status(s, sector_num, nb_sectors, pnum);
 199     if (pos > 0) {
 200         return pos;
 201     }
 202
 203     idx = sector_num / s->tracks;
 204     if (idx >= s->bat_size) {
 205         return -EINVAL;
 206     }
 207
 208     to_allocate = DIV_ROUND_UP(sector_num + *pnum, s->tracks) - idx;
 209     space = to_allocate * s->tracks;
 210     if (s->data_end + space > bdrv_getlength(bs->file->bs) >> BDRV_SECTOR_BITS) {
 211         int ret;
 212         space += s->prealloc_size;
 213         if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) {
 214             ret = bdrv_pwrite_zeroes(bs->file,
 215                                      s->data_end << BDRV_SECTOR_BITS,
 216                                      space << BDRV_SECTOR_BITS, 0);
 217         } else {
 218             ret = bdrv_truncate(bs->file->bs,
 219                                 (s->data_end + space) << BDRV_SECTOR_BITS);
 220         }
 221         if (ret < 0) {
 222             return ret;
 223         }
 224     }
 225
 226     for (i = 0; i < to_allocate; i++) {
 227         s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier);
 228         s->data_end += s->tracks;
 229         bitmap_set(s->bat_dirty_bmap,
 230                    bat_entry_off(idx + i) / s->bat_dirty_block, 1);
 231     }
 232
 233     return bat2sect(s, idx) + sector_num % s->tracks;
 234 }
 235
 236
 237 static coroutine_fn int parallels_co_flush_to_os(BlockDriverState *bs)
 238 {
 239     BDRVParallelsState *s = bs->opaque;
 240     unsigned long size = DIV_ROUND_UP(s->header_size, s->bat_dirty_block);
 241     unsigned long bit;
 242
 243     qemu_co_mutex_lock(&s->lock);
 244
 245     bit = find_first_bit(s->bat_dirty_bmap, size);
 246     while (bit < size) {
 247         uint32_t off = bit * s->bat_dirty_block;
 248         uint32_t to_write = s->bat_dirty_block;
 249         int ret;
 250
 251         if (off + to_write > s->header_size) {
 252             to_write = s->header_size - off;
 253         }
 254         ret = bdrv_pwrite(bs->file, off, (uint8_t *)s->header + off,
 255                           to_write);
 256         if (ret < 0) {
 257             qemu_co_mutex_unlock(&s->lock);
 258             return ret;
 259         }
 260         bit = find_next_bit(s->bat_dirty_bmap, size, bit + 1);
 261     }
 262     bitmap_zero(s->bat_dirty_bmap, size);
 263
 264     qemu_co_mutex_unlock(&s->lock);
 265     return 0;
 266 }
 267
 268
 269 static int64_t coroutine_fn parallels_co_get_block_status(BlockDriverState *bs,
 270         int64_t sector_num, int nb_sectors, int *pnum, BlockDriverState **file)
 271 {
 272     BDRVParallelsState *s = bs->opaque;
 273     int64_t offset;
 274
 275     qemu_co_mutex_lock(&s->lock);
 276     offset = block_status(s, sector_num, nb_sectors, pnum);
 277     qemu_co_mutex_unlock(&s->lock);
 278
 279     if (offset < 0) {
 280         return 0;
 281     }
 282
 283     *file = bs->file->bs;
 284     return (offset << BDRV_SECTOR_BITS) |
 285         BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
 286 }
 287
 288 static coroutine_fn int parallels_co_writev(BlockDriverState *bs,
 289         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
 290 {
 291     BDRVParallelsState *s = bs->opaque;
 292     uint64_t bytes_done = 0;
 293     QEMUIOVector hd_qiov;
 294     int ret = 0;
 295
 296     qemu_iovec_init(&hd_qiov, qiov->niov);
 297
 298     while (nb_sectors > 0) {
 299         int64_t position;
 300         int n, nbytes;
 301
 302         qemu_co_mutex_lock(&s->lock);
 303         position = allocate_clusters(bs, sector_num, nb_sectors, &n);
 304         qemu_co_mutex_unlock(&s->lock);
 305         if (position < 0) {
 306             ret = (int)position;
 307             break;
 308         }
 309
 310         nbytes = n << BDRV_SECTOR_BITS;
 311
 312         qemu_iovec_reset(&hd_qiov);
 313         qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);
 314
 315         ret = bdrv_co_writev(bs->file, position, n, &hd_qiov);
 316         if (ret < 0) {
 317             break;
 318         }
 319
 320         nb_sectors -= n;
 321         sector_num += n;
 322         bytes_done += nbytes;
 323     }
 324
 325     qemu_iovec_destroy(&hd_qiov);
 326     return ret;
 327 }
 328
 329 static coroutine_fn int parallels_co_readv(BlockDriverState *bs,
 330         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
 331 {
 332     BDRVParallelsState *s = bs->opaque;
 333     uint64_t bytes_done = 0;
 334     QEMUIOVector hd_qiov;
 335     int ret = 0;
 336
 337     qemu_iovec_init(&hd_qiov, qiov->niov);
 338
 339     while (nb_sectors > 0) {
 340         int64_t position;
 341         int n, nbytes;
 342
 343         qemu_co_mutex_lock(&s->lock);
 344         position = block_status(s, sector_num, nb_sectors, &n);
 345         qemu_co_mutex_unlock(&s->lock);
 346
 347         nbytes = n << BDRV_SECTOR_BITS;
 348
 349         if (position < 0) {
 350             qemu_iovec_memset(qiov, bytes_done, 0, nbytes);
 351         } else {
 352             qemu_iovec_reset(&hd_qiov);
 353             qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);
 354
 355             ret = bdrv_co_readv(bs->file, position, n, &hd_qiov);
 356             if (ret < 0) {
 357                 break;
 358             }
 359         }
 360
 361         nb_sectors -= n;
 362         sector_num += n;
 363         bytes_done += nbytes;
 364     }
 365
 366     qemu_iovec_destroy(&hd_qiov);
 367     return ret;
 368 }
 369
 370
 371 static int parallels_check(BlockDriverState *bs, BdrvCheckResult *res,
 372                            BdrvCheckMode fix)
 373 {
 374     BDRVParallelsState *s = bs->opaque;
 375     int64_t size, prev_off, high_off;
 376     int ret;
 377     uint32_t i;
 378     bool flush_bat = false;
 379     int cluster_size = s->tracks << BDRV_SECTOR_BITS;
 380
 381     size = bdrv_getlength(bs->file->bs);
 382     if (size < 0) {
 383         res->check_errors++;
 384         return size;
 385     }
 386
 387     if (s->header_unclean) {
 388         fprintf(stderr, "%s image was not closed correctly\n",
 389                 fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR");
 390         res->corruptions++;
 391         if (fix & BDRV_FIX_ERRORS) {
 392             /* parallels_close will do the job right */
 393             res->corruptions_fixed++;
 394             s->header_unclean = false;
 395         }
 396     }
 397
 398     res->bfi.total_clusters = s->bat_size;
 399     res->bfi.compressed_clusters = 0; /* compression is not supported */
 400
 401     high_off = 0;
 402     prev_off = 0;
 403     for (i = 0; i < s->bat_size; i++) {
 404         int64_t off = bat2sect(s, i) << BDRV_SECTOR_BITS;
 405         if (off == 0) {
 406             prev_off = 0;
 407             continue;
 408         }
 409
 410         /* cluster outside the image */
 411         if (off > size) {
 412             fprintf(stderr, "%s cluster %u is outside image\n",
 413                     fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", i);
 414             res->corruptions++;
 415             if (fix & BDRV_FIX_ERRORS) {
 416                 prev_off = 0;
 417                 s->bat_bitmap[i] = 0;
 418                 res->corruptions_fixed++;
 419                 flush_bat = true;
 420                 continue;
 421             }
 422         }
 423
 424         res->bfi.allocated_clusters++;
 425         if (off > high_off) {
 426             high_off = off;
 427         }
 428
 429         if (prev_off != 0 && (prev_off + cluster_size) != off) {
 430             res->bfi.fragmented_clusters++;
 431         }
 432         prev_off = off;
 433     }
 434
 435     if (flush_bat) {
 436         ret = bdrv_pwrite_sync(bs->file, 0, s->header, s->header_size);
 437         if (ret < 0) {
 438             res->check_errors++;
 439             return ret;
 440         }
 441     }
 442
 443     res->image_end_offset = high_off + cluster_size;
 444     if (size > res->image_end_offset) {
 445         int64_t count;
 446         count = DIV_ROUND_UP(size - res->image_end_offset, cluster_size);
 447         fprintf(stderr, "%s space leaked at the end of the image %" PRId64 "\n",
 448                 fix & BDRV_FIX_LEAKS ? "Repairing" : "ERROR",
 449                 size - res->image_end_offset);
 450         res->leaks += count;
 451         if (fix & BDRV_FIX_LEAKS) {
 452             ret = bdrv_truncate(bs->file->bs, res->image_end_offset);
 453             if (ret < 0) {
 454                 res->check_errors++;
 455                 return ret;
 456             }
 457             res->leaks_fixed += count;
 458         }
 459     }
 460
 461     return 0;
 462 }
 463
 464
 465 static int parallels_create(const char *filename, QemuOpts *opts, Error **errp)
 466 {
 467     int64_t total_size, cl_size;
 468     uint8_t tmp[BDRV_SECTOR_SIZE];
 469     Error *local_err = NULL;
 470     BlockBackend *file;
 471     uint32_t bat_entries, bat_sectors;
 472     ParallelsHeader header;
 473     int ret;
 474
 475     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
 476                           BDRV_SECTOR_SIZE);
 477     cl_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE,
 478                           DEFAULT_CLUSTER_SIZE), BDRV_SECTOR_SIZE);
 479     if (total_size >= MAX_PARALLELS_IMAGE_FACTOR * cl_size) {
 480         error_propagate(errp, local_err);
 481         return -E2BIG;
 482     }
 483
 484     ret = bdrv_create_file(filename, opts, &local_err);
 485     if (ret < 0) {
 486         error_propagate(errp, local_err);
 487         return ret;
 488     }
 489
 490     file = blk_new_open(filename, NULL, NULL,
 491                         BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err);
 492     if (file == NULL) {
 493         error_propagate(errp, local_err);
 494         return -EIO;
 495     }
 496
 497     blk_set_allow_write_beyond_eof(file, true);
 498
 499     ret = blk_truncate(file, 0);
 500     if (ret < 0) {
 501         goto exit;
 502     }
 503
 504     bat_entries = DIV_ROUND_UP(total_size, cl_size);
 505     bat_sectors = DIV_ROUND_UP(bat_entry_off(bat_entries), cl_size);
 506     bat_sectors = (bat_sectors *  cl_size) >> BDRV_SECTOR_BITS;
 507
 508     memset(&header, 0, sizeof(header));
 509     memcpy(header.magic, HEADER_MAGIC2, sizeof(header.magic));
 510     header.version = cpu_to_le32(HEADER_VERSION);
 511     /* don't care much about geometry, it is not used on image level */
 512     header.heads = cpu_to_le32(16);
 513     header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE / 16 / 32);
 514     header.tracks = cpu_to_le32(cl_size >> BDRV_SECTOR_BITS);
 515     header.bat_entries = cpu_to_le32(bat_entries);
 516     header.nb_sectors = cpu_to_le64(DIV_ROUND_UP(total_size, BDRV_SECTOR_SIZE));
 517     header.data_off = cpu_to_le32(bat_sectors);
 518
 519     /* write all the data */
 520     memset(tmp, 0, sizeof(tmp));
 521     memcpy(tmp, &header, sizeof(header));
 522
 523     ret = blk_pwrite(file, 0, tmp, BDRV_SECTOR_SIZE, 0);
 524     if (ret < 0) {
 525         goto exit;
 526     }
 527     ret = blk_pwrite_zeroes(file, BDRV_SECTOR_SIZE,
 528                             (bat_sectors - 1) << BDRV_SECTOR_BITS, 0);
 529     if (ret < 0) {
 530         goto exit;
 531     }
 532     ret = 0;
 533
 534 done:
 535     blk_unref(file);
 536     return ret;
 537
 538 exit:
 539     error_setg_errno(errp, -ret, "Failed to create Parallels image");
 540     goto done;
 541 }
 542
 543
 544 static int parallels_probe(const uint8_t *buf, int buf_size,
 545                            const char *filename)
 546 {
 547     const ParallelsHeader *ph = (const void *)buf;
 548
 549     if (buf_size < sizeof(ParallelsHeader)) {
 550         return 0;
 551     }
 552
 553     if ((!memcmp(ph->magic, HEADER_MAGIC, 16) ||
 554            !memcmp(ph->magic, HEADER_MAGIC2, 16)) &&
 555            (le32_to_cpu(ph->version) == HEADER_VERSION)) {
 556         return 100;
 557     }
 558
 559     return 0;
 560 }
 561
 562 static int parallels_update_header(BlockDriverState *bs)
 563 {
 564     BDRVParallelsState *s = bs->opaque;
 565     unsigned size = MAX(bdrv_opt_mem_align(bs->file->bs),
 566                         sizeof(ParallelsHeader));
 567
 568     if (size > s->header_size) {
 569         size = s->header_size;
 570     }
 571     return bdrv_pwrite_sync(bs->file, 0, s->header, size);
 572 }
 573
 574 static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
 575                           Error **errp)
 576 {
 577     BDRVParallelsState *s = bs->opaque;
 578     ParallelsHeader ph;
 579     int ret, size, i;
 580     QemuOpts *opts = NULL;
 581     Error *local_err = NULL;
 582     char *buf;
 583
 584     ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
 585     if (ret < 0) {
 586         goto fail;
 587     }
 588
 589     bs->total_sectors = le64_to_cpu(ph.nb_sectors);
 590
 591     if (le32_to_cpu(ph.version) != HEADER_VERSION) {
 592         goto fail_format;
 593     }
 594     if (!memcmp(ph.magic, HEADER_MAGIC, 16)) {
 595         s->off_multiplier = 1;
 596         bs->total_sectors = 0xffffffff & bs->total_sectors;
 597     } else if (!memcmp(ph.magic, HEADER_MAGIC2, 16)) {
 598         s->off_multiplier = le32_to_cpu(ph.tracks);
 599     } else {
 600         goto fail_format;
 601     }
 602
 603     s->tracks = le32_to_cpu(ph.tracks);
 604     if (s->tracks == 0) {
 605         error_setg(errp, "Invalid image: Zero sectors per track");
 606         ret = -EINVAL;
 607         goto fail;
 608     }
 609     if (s->tracks > INT32_MAX/513) {
 610         error_setg(errp, "Invalid image: Too big cluster");
 611         ret = -EFBIG;
 612         goto fail;
 613     }
 614
 615     s->bat_size = le32_to_cpu(ph.bat_entries);
 616     if (s->bat_size > INT_MAX / sizeof(uint32_t)) {
 617         error_setg(errp, "Catalog too large");
 618         ret = -EFBIG;
 619         goto fail;
 620     }
 621
 622     size = bat_entry_off(s->bat_size);
 623     s->header_size = ROUND_UP(size, bdrv_opt_mem_align(bs->file->bs));
 624     s->header = qemu_try_blockalign(bs->file->bs, s->header_size);
 625     if (s->header == NULL) {
 626         ret = -ENOMEM;
 627         goto fail;
 628     }
 629     s->data_end = le32_to_cpu(ph.data_off);
 630     if (s->data_end == 0) {
 631         s->data_end = ROUND_UP(bat_entry_off(s->bat_size), BDRV_SECTOR_SIZE);
 632     }
 633     if (s->data_end < s->header_size) {
 634         /* there is not enough unused space to fit to block align between BAT
 635            and actual data. We can't avoid read-modify-write... */
 636         s->header_size = size;
 637     }
 638
 639     ret = bdrv_pread(bs->file, 0, s->header, s->header_size);
 640     if (ret < 0) {
 641         goto fail;
 642     }
 643     s->bat_bitmap = (uint32_t *)(s->header + 1);
 644
 645     for (i = 0; i < s->bat_size; i++) {
 646         int64_t off = bat2sect(s, i);
 647         if (off >= s->data_end) {
 648             s->data_end = off + s->tracks;
 649         }
 650     }
 651
 652     if (le32_to_cpu(ph.inuse) == HEADER_INUSE_MAGIC) {
 653         /* Image was not closed correctly. The check is mandatory */
 654         s->header_unclean = true;
 655         if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) {
 656             error_setg(errp, "parallels: Image was not closed correctly; "
 657                        "cannot be opened read/write");
 658             ret = -EACCES;
 659             goto fail;
 660         }
 661     }
 662
 663     opts = qemu_opts_create(&parallels_runtime_opts, NULL, 0, &local_err);
 664     if (local_err != NULL) {
 665         goto fail_options;
 666     }
 667
 668     qemu_opts_absorb_qdict(opts, options, &local_err);
 669     if (local_err != NULL) {
 670         goto fail_options;
 671     }
 672
 673     s->prealloc_size =
 674         qemu_opt_get_size_del(opts, PARALLELS_OPT_PREALLOC_SIZE, 0);
 675     s->prealloc_size = MAX(s->tracks, s->prealloc_size >> BDRV_SECTOR_BITS);
 676     buf = qemu_opt_get_del(opts, PARALLELS_OPT_PREALLOC_MODE);
 677     s->prealloc_mode = qapi_enum_parse(prealloc_mode_lookup, buf,
 678             PRL_PREALLOC_MODE__MAX, PRL_PREALLOC_MODE_FALLOCATE, &local_err);
 679     g_free(buf);
 680     if (local_err != NULL) {
 681         goto fail_options;
 682     }
 683     if (!bdrv_has_zero_init(bs->file->bs) ||
 684             bdrv_truncate(bs->file->bs, bdrv_getlength(bs->file->bs)) != 0) {
 685         s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE;
 686     }
 687
 688     if (flags & BDRV_O_RDWR) {
 689         s->header->inuse = cpu_to_le32(HEADER_INUSE_MAGIC);
 690         ret = parallels_update_header(bs);
 691         if (ret < 0) {
 692             goto fail;
 693         }
 694     }
 695
 696     s->bat_dirty_block = 4 * getpagesize();
 697     s->bat_dirty_bmap =
 698         bitmap_new(DIV_ROUND_UP(s->header_size, s->bat_dirty_block));
 699
 700     qemu_co_mutex_init(&s->lock);
 701     return 0;
 702
 703 fail_format:
 704     error_setg(errp, "Image not in Parallels format");
 705     ret = -EINVAL;
 706 fail:
 707     qemu_vfree(s->header);
 708     return ret;
 709
 710 fail_options:
 711     error_propagate(errp, local_err);
 712     ret = -EINVAL;
 713     goto fail;
 714 }
 715
 716
 717 static void parallels_close(BlockDriverState *bs)
 718 {
 719     BDRVParallelsState *s = bs->opaque;
 720
 721     if (bs->open_flags & BDRV_O_RDWR) {
 722         s->header->inuse = 0;
 723         parallels_update_header(bs);
 724     }
 725
 726     if (bs->open_flags & BDRV_O_RDWR) {
 727         bdrv_truncate(bs->file->bs, s->data_end << BDRV_SECTOR_BITS);
 728     }
 729
 730     g_free(s->bat_dirty_bmap);
 731     qemu_vfree(s->header);
 732 }
 733
 734 static QemuOptsList parallels_create_opts = {
 735     .name = "parallels-create-opts",
 736     .head = QTAILQ_HEAD_INITIALIZER(parallels_create_opts.head),
 737     .desc = {
 738         {
 739             .name = BLOCK_OPT_SIZE,
 740             .type = QEMU_OPT_SIZE,
 741             .help = "Virtual disk size",
 742         },
 743         {
 744             .name = BLOCK_OPT_CLUSTER_SIZE,
 745             .type = QEMU_OPT_SIZE,
 746             .help = "Parallels image cluster size",
 747             .def_value_str = stringify(DEFAULT_CLUSTER_SIZE),
 748         },
 749         { /* end of list */ }
 750     }
 751 };
 752
 753 static BlockDriver bdrv_parallels = {
 754     .format_name        = "parallels",
 755     .instance_size      = sizeof(BDRVParallelsState),
 756     .bdrv_probe         = parallels_probe,
 757     .bdrv_open          = parallels_open,
 758     .bdrv_close         = parallels_close,
 759     .bdrv_co_get_block_status = parallels_co_get_block_status,
 760     .bdrv_has_zero_init       = bdrv_has_zero_init_1,
 761     .bdrv_co_flush_to_os      = parallels_co_flush_to_os,
 762     .bdrv_co_readv  = parallels_co_readv,
 763     .bdrv_co_writev = parallels_co_writev,
 764
 765     .bdrv_create    = parallels_create,
 766     .bdrv_check     = parallels_check,
 767     .create_opts    = &parallels_create_opts,
 768 };
 769
 770 static void bdrv_parallels_init(void)
 771 {
 772     bdrv_register(&bdrv_parallels);
 773 }
 774
 775 block_init(bdrv_parallels_init);