qemu/block/parallels.c
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   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
  52typedef 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
  66typedef enum ParallelsPreallocMode {
  67    PRL_PREALLOC_MODE_FALLOCATE = 0,
  68    PRL_PREALLOC_MODE_TRUNCATE = 1,
  69    PRL_PREALLOC_MODE__MAX = 2,
  70} ParallelsPreallocMode;
  71
  72static const char *prealloc_mode_lookup[] = {
  73    "falloc",
  74    "truncate",
  75    NULL,
  76};
  77
  78
  79typedef 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
 109static 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 = "128M",
 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
 131static 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
 136static uint32_t bat_entry_off(uint32_t idx)
 137{
 138    return sizeof(ParallelsHeader) + sizeof(uint32_t) * idx;
 139}
 140
 141static 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
 155static 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
 162static 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
 191static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num,
 192                                 int nb_sectors, int *pnum)
 193{
 194    BDRVParallelsState *s = bs->opaque;
 195    int64_t pos, space, idx, to_allocate, i, len;
 196
 197    pos = block_status(s, sector_num, nb_sectors, pnum);
 198    if (pos > 0) {
 199        return pos;
 200    }
 201
 202    idx = sector_num / s->tracks;
 203    to_allocate = DIV_ROUND_UP(sector_num + *pnum, s->tracks) - idx;
 204
 205    /* This function is called only by parallels_co_writev(), which will never
 206     * pass a sector_num at or beyond the end of the image (because the block
 207     * layer never passes such a sector_num to that function). Therefore, idx
 208     * is always below s->bat_size.
 209     * block_status() will limit *pnum so that sector_num + *pnum will not
 210     * exceed the image end. Therefore, idx + to_allocate cannot exceed
 211     * s->bat_size.
 212     * Note that s->bat_size is an unsigned int, therefore idx + to_allocate
 213     * will always fit into a uint32_t. */
 214    assert(idx < s->bat_size && idx + to_allocate <= s->bat_size);
 215
 216    space = to_allocate * s->tracks;
 217    len = bdrv_getlength(bs->file->bs);
 218    if (len < 0) {
 219        return len;
 220    }
 221    if (s->data_end + space > (len >> BDRV_SECTOR_BITS)) {
 222        int ret;
 223        space += s->prealloc_size;
 224        if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) {
 225            ret = bdrv_pwrite_zeroes(bs->file,
 226                                     s->data_end << BDRV_SECTOR_BITS,
 227                                     space << BDRV_SECTOR_BITS, 0);
 228        } else {
 229            ret = bdrv_truncate(bs->file,
 230                                (s->data_end + space) << BDRV_SECTOR_BITS,
 231                                PREALLOC_MODE_OFF, NULL);
 232        }
 233        if (ret < 0) {
 234            return ret;
 235        }
 236    }
 237
 238    for (i = 0; i < to_allocate; i++) {
 239        s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier);
 240        s->data_end += s->tracks;
 241        bitmap_set(s->bat_dirty_bmap,
 242                   bat_entry_off(idx + i) / s->bat_dirty_block, 1);
 243    }
 244
 245    return bat2sect(s, idx) + sector_num % s->tracks;
 246}
 247
 248
 249static coroutine_fn int parallels_co_flush_to_os(BlockDriverState *bs)
 250{
 251    BDRVParallelsState *s = bs->opaque;
 252    unsigned long size = DIV_ROUND_UP(s->header_size, s->bat_dirty_block);
 253    unsigned long bit;
 254
 255    qemu_co_mutex_lock(&s->lock);
 256
 257    bit = find_first_bit(s->bat_dirty_bmap, size);
 258    while (bit < size) {
 259        uint32_t off = bit * s->bat_dirty_block;
 260        uint32_t to_write = s->bat_dirty_block;
 261        int ret;
 262
 263        if (off + to_write > s->header_size) {
 264            to_write = s->header_size - off;
 265        }
 266        ret = bdrv_pwrite(bs->file, off, (uint8_t *)s->header + off,
 267                          to_write);
 268        if (ret < 0) {
 269            qemu_co_mutex_unlock(&s->lock);
 270            return ret;
 271        }
 272        bit = find_next_bit(s->bat_dirty_bmap, size, bit + 1);
 273    }
 274    bitmap_zero(s->bat_dirty_bmap, size);
 275
 276    qemu_co_mutex_unlock(&s->lock);
 277    return 0;
 278}
 279
 280
 281static int64_t coroutine_fn parallels_co_get_block_status(BlockDriverState *bs,
 282        int64_t sector_num, int nb_sectors, int *pnum, BlockDriverState **file)
 283{
 284    BDRVParallelsState *s = bs->opaque;
 285    int64_t offset;
 286
 287    qemu_co_mutex_lock(&s->lock);
 288    offset = block_status(s, sector_num, nb_sectors, pnum);
 289    qemu_co_mutex_unlock(&s->lock);
 290
 291    if (offset < 0) {
 292        return 0;
 293    }
 294
 295    *file = bs->file->bs;
 296    return (offset << BDRV_SECTOR_BITS) |
 297        BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
 298}
 299
 300static coroutine_fn int parallels_co_writev(BlockDriverState *bs,
 301        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
 302{
 303    BDRVParallelsState *s = bs->opaque;
 304    uint64_t bytes_done = 0;
 305    QEMUIOVector hd_qiov;
 306    int ret = 0;
 307
 308    qemu_iovec_init(&hd_qiov, qiov->niov);
 309
 310    while (nb_sectors > 0) {
 311        int64_t position;
 312        int n, nbytes;
 313
 314        qemu_co_mutex_lock(&s->lock);
 315        position = allocate_clusters(bs, sector_num, nb_sectors, &n);
 316        qemu_co_mutex_unlock(&s->lock);
 317        if (position < 0) {
 318            ret = (int)position;
 319            break;
 320        }
 321
 322        nbytes = n << BDRV_SECTOR_BITS;
 323
 324        qemu_iovec_reset(&hd_qiov);
 325        qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);
 326
 327        ret = bdrv_co_writev(bs->file, position, n, &hd_qiov);
 328        if (ret < 0) {
 329            break;
 330        }
 331
 332        nb_sectors -= n;
 333        sector_num += n;
 334        bytes_done += nbytes;
 335    }
 336
 337    qemu_iovec_destroy(&hd_qiov);
 338    return ret;
 339}
 340
 341static coroutine_fn int parallels_co_readv(BlockDriverState *bs,
 342        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
 343{
 344    BDRVParallelsState *s = bs->opaque;
 345    uint64_t bytes_done = 0;
 346    QEMUIOVector hd_qiov;
 347    int ret = 0;
 348
 349    qemu_iovec_init(&hd_qiov, qiov->niov);
 350
 351    while (nb_sectors > 0) {
 352        int64_t position;
 353        int n, nbytes;
 354
 355        qemu_co_mutex_lock(&s->lock);
 356        position = block_status(s, sector_num, nb_sectors, &n);
 357        qemu_co_mutex_unlock(&s->lock);
 358
 359        nbytes = n << BDRV_SECTOR_BITS;
 360
 361        if (position < 0) {
 362            qemu_iovec_memset(qiov, bytes_done, 0, nbytes);
 363        } else {
 364            qemu_iovec_reset(&hd_qiov);
 365            qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);
 366
 367            ret = bdrv_co_readv(bs->file, position, n, &hd_qiov);
 368            if (ret < 0) {
 369                break;
 370            }
 371        }
 372
 373        nb_sectors -= n;
 374        sector_num += n;
 375        bytes_done += nbytes;
 376    }
 377
 378    qemu_iovec_destroy(&hd_qiov);
 379    return ret;
 380}
 381
 382
 383static int parallels_check(BlockDriverState *bs, BdrvCheckResult *res,
 384                           BdrvCheckMode fix)
 385{
 386    BDRVParallelsState *s = bs->opaque;
 387    int64_t size, prev_off, high_off;
 388    int ret;
 389    uint32_t i;
 390    bool flush_bat = false;
 391    int cluster_size = s->tracks << BDRV_SECTOR_BITS;
 392
 393    size = bdrv_getlength(bs->file->bs);
 394    if (size < 0) {
 395        res->check_errors++;
 396        return size;
 397    }
 398
 399    if (s->header_unclean) {
 400        fprintf(stderr, "%s image was not closed correctly\n",
 401                fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR");
 402        res->corruptions++;
 403        if (fix & BDRV_FIX_ERRORS) {
 404            /* parallels_close will do the job right */
 405            res->corruptions_fixed++;
 406            s->header_unclean = false;
 407        }
 408    }
 409
 410    res->bfi.total_clusters = s->bat_size;
 411    res->bfi.compressed_clusters = 0; /* compression is not supported */
 412
 413    high_off = 0;
 414    prev_off = 0;
 415    for (i = 0; i < s->bat_size; i++) {
 416        int64_t off = bat2sect(s, i) << BDRV_SECTOR_BITS;
 417        if (off == 0) {
 418            prev_off = 0;
 419            continue;
 420        }
 421
 422        /* cluster outside the image */
 423        if (off > size) {
 424            fprintf(stderr, "%s cluster %u is outside image\n",
 425                    fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", i);
 426            res->corruptions++;
 427            if (fix & BDRV_FIX_ERRORS) {
 428                prev_off = 0;
 429                s->bat_bitmap[i] = 0;
 430                res->corruptions_fixed++;
 431                flush_bat = true;
 432                continue;
 433            }
 434        }
 435
 436        res->bfi.allocated_clusters++;
 437        if (off > high_off) {
 438            high_off = off;
 439        }
 440
 441        if (prev_off != 0 && (prev_off + cluster_size) != off) {
 442            res->bfi.fragmented_clusters++;
 443        }
 444        prev_off = off;
 445    }
 446
 447    if (flush_bat) {
 448        ret = bdrv_pwrite_sync(bs->file, 0, s->header, s->header_size);
 449        if (ret < 0) {
 450            res->check_errors++;
 451            return ret;
 452        }
 453    }
 454
 455    res->image_end_offset = high_off + cluster_size;
 456    if (size > res->image_end_offset) {
 457        int64_t count;
 458        count = DIV_ROUND_UP(size - res->image_end_offset, cluster_size);
 459        fprintf(stderr, "%s space leaked at the end of the image %" PRId64 "\n",
 460                fix & BDRV_FIX_LEAKS ? "Repairing" : "ERROR",
 461                size - res->image_end_offset);
 462        res->leaks += count;
 463        if (fix & BDRV_FIX_LEAKS) {
 464            Error *local_err = NULL;
 465            ret = bdrv_truncate(bs->file, res->image_end_offset,
 466                                PREALLOC_MODE_OFF, &local_err);
 467            if (ret < 0) {
 468                error_report_err(local_err);
 469                res->check_errors++;
 470                return ret;
 471            }
 472            res->leaks_fixed += count;
 473        }
 474    }
 475
 476    return 0;
 477}
 478
 479
 480static int parallels_create(const char *filename, QemuOpts *opts, Error **errp)
 481{
 482    int64_t total_size, cl_size;
 483    uint8_t tmp[BDRV_SECTOR_SIZE];
 484    Error *local_err = NULL;
 485    BlockBackend *file;
 486    uint32_t bat_entries, bat_sectors;
 487    ParallelsHeader header;
 488    int ret;
 489
 490    total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
 491                          BDRV_SECTOR_SIZE);
 492    cl_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE,
 493                          DEFAULT_CLUSTER_SIZE), BDRV_SECTOR_SIZE);
 494    if (total_size >= MAX_PARALLELS_IMAGE_FACTOR * cl_size) {
 495        error_propagate(errp, local_err);
 496        return -E2BIG;
 497    }
 498
 499    ret = bdrv_create_file(filename, opts, &local_err);
 500    if (ret < 0) {
 501        error_propagate(errp, local_err);
 502        return ret;
 503    }
 504
 505    file = blk_new_open(filename, NULL, NULL,
 506                        BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,
 507                        &local_err);
 508    if (file == NULL) {
 509        error_propagate(errp, local_err);
 510        return -EIO;
 511    }
 512
 513    blk_set_allow_write_beyond_eof(file, true);
 514
 515    ret = blk_truncate(file, 0, PREALLOC_MODE_OFF, errp);
 516    if (ret < 0) {
 517        goto exit;
 518    }
 519
 520    bat_entries = DIV_ROUND_UP(total_size, cl_size);
 521    bat_sectors = DIV_ROUND_UP(bat_entry_off(bat_entries), cl_size);
 522    bat_sectors = (bat_sectors *  cl_size) >> BDRV_SECTOR_BITS;
 523
 524    memset(&header, 0, sizeof(header));
 525    memcpy(header.magic, HEADER_MAGIC2, sizeof(header.magic));
 526    header.version = cpu_to_le32(HEADER_VERSION);
 527    /* don't care much about geometry, it is not used on image level */
 528    header.heads = cpu_to_le32(16);
 529    header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE / 16 / 32);
 530    header.tracks = cpu_to_le32(cl_size >> BDRV_SECTOR_BITS);
 531    header.bat_entries = cpu_to_le32(bat_entries);
 532    header.nb_sectors = cpu_to_le64(DIV_ROUND_UP(total_size, BDRV_SECTOR_SIZE));
 533    header.data_off = cpu_to_le32(bat_sectors);
 534
 535    /* write all the data */
 536    memset(tmp, 0, sizeof(tmp));
 537    memcpy(tmp, &header, sizeof(header));
 538
 539    ret = blk_pwrite(file, 0, tmp, BDRV_SECTOR_SIZE, 0);
 540    if (ret < 0) {
 541        goto exit;
 542    }
 543    ret = blk_pwrite_zeroes(file, BDRV_SECTOR_SIZE,
 544                            (bat_sectors - 1) << BDRV_SECTOR_BITS, 0);
 545    if (ret < 0) {
 546        goto exit;
 547    }
 548    ret = 0;
 549
 550done:
 551    blk_unref(file);
 552    return ret;
 553
 554exit:
 555    error_setg_errno(errp, -ret, "Failed to create Parallels image");
 556    goto done;
 557}
 558
 559
 560static int parallels_probe(const uint8_t *buf, int buf_size,
 561                           const char *filename)
 562{
 563    const ParallelsHeader *ph = (const void *)buf;
 564
 565    if (buf_size < sizeof(ParallelsHeader)) {
 566        return 0;
 567    }
 568
 569    if ((!memcmp(ph->magic, HEADER_MAGIC, 16) ||
 570           !memcmp(ph->magic, HEADER_MAGIC2, 16)) &&
 571           (le32_to_cpu(ph->version) == HEADER_VERSION)) {
 572        return 100;
 573    }
 574
 575    return 0;
 576}
 577
 578static int parallels_update_header(BlockDriverState *bs)
 579{
 580    BDRVParallelsState *s = bs->opaque;
 581    unsigned size = MAX(bdrv_opt_mem_align(bs->file->bs),
 582                        sizeof(ParallelsHeader));
 583
 584    if (size > s->header_size) {
 585        size = s->header_size;
 586    }
 587    return bdrv_pwrite_sync(bs->file, 0, s->header, size);
 588}
 589
 590static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
 591                          Error **errp)
 592{
 593    BDRVParallelsState *s = bs->opaque;
 594    ParallelsHeader ph;
 595    int ret, size, i;
 596    QemuOpts *opts = NULL;
 597    Error *local_err = NULL;
 598    char *buf;
 599
 600    bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
 601                               false, errp);
 602    if (!bs->file) {
 603        return -EINVAL;
 604    }
 605
 606    ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
 607    if (ret < 0) {
 608        goto fail;
 609    }
 610
 611    bs->total_sectors = le64_to_cpu(ph.nb_sectors);
 612
 613    if (le32_to_cpu(ph.version) != HEADER_VERSION) {
 614        goto fail_format;
 615    }
 616    if (!memcmp(ph.magic, HEADER_MAGIC, 16)) {
 617        s->off_multiplier = 1;
 618        bs->total_sectors = 0xffffffff & bs->total_sectors;
 619    } else if (!memcmp(ph.magic, HEADER_MAGIC2, 16)) {
 620        s->off_multiplier = le32_to_cpu(ph.tracks);
 621    } else {
 622        goto fail_format;
 623    }
 624
 625    s->tracks = le32_to_cpu(ph.tracks);
 626    if (s->tracks == 0) {
 627        error_setg(errp, "Invalid image: Zero sectors per track");
 628        ret = -EINVAL;
 629        goto fail;
 630    }
 631    if (s->tracks > INT32_MAX/513) {
 632        error_setg(errp, "Invalid image: Too big cluster");
 633        ret = -EFBIG;
 634        goto fail;
 635    }
 636
 637    s->bat_size = le32_to_cpu(ph.bat_entries);
 638    if (s->bat_size > INT_MAX / sizeof(uint32_t)) {
 639        error_setg(errp, "Catalog too large");
 640        ret = -EFBIG;
 641        goto fail;
 642    }
 643
 644    size = bat_entry_off(s->bat_size);
 645    s->header_size = ROUND_UP(size, bdrv_opt_mem_align(bs->file->bs));
 646    s->header = qemu_try_blockalign(bs->file->bs, s->header_size);
 647    if (s->header == NULL) {
 648        ret = -ENOMEM;
 649        goto fail;
 650    }
 651    s->data_end = le32_to_cpu(ph.data_off);
 652    if (s->data_end == 0) {
 653        s->data_end = ROUND_UP(bat_entry_off(s->bat_size), BDRV_SECTOR_SIZE);
 654    }
 655    if (s->data_end < s->header_size) {
 656        /* there is not enough unused space to fit to block align between BAT
 657           and actual data. We can't avoid read-modify-write... */
 658        s->header_size = size;
 659    }
 660
 661    ret = bdrv_pread(bs->file, 0, s->header, s->header_size);
 662    if (ret < 0) {
 663        goto fail;
 664    }
 665    s->bat_bitmap = (uint32_t *)(s->header + 1);
 666
 667    for (i = 0; i < s->bat_size; i++) {
 668        int64_t off = bat2sect(s, i);
 669        if (off >= s->data_end) {
 670            s->data_end = off + s->tracks;
 671        }
 672    }
 673
 674    if (le32_to_cpu(ph.inuse) == HEADER_INUSE_MAGIC) {
 675        /* Image was not closed correctly. The check is mandatory */
 676        s->header_unclean = true;
 677        if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) {
 678            error_setg(errp, "parallels: Image was not closed correctly; "
 679                       "cannot be opened read/write");
 680            ret = -EACCES;
 681            goto fail;
 682        }
 683    }
 684
 685    opts = qemu_opts_create(&parallels_runtime_opts, NULL, 0, &local_err);
 686    if (local_err != NULL) {
 687        goto fail_options;
 688    }
 689
 690    qemu_opts_absorb_qdict(opts, options, &local_err);
 691    if (local_err != NULL) {
 692        goto fail_options;
 693    }
 694
 695    s->prealloc_size =
 696        qemu_opt_get_size_del(opts, PARALLELS_OPT_PREALLOC_SIZE, 0);
 697    s->prealloc_size = MAX(s->tracks, s->prealloc_size >> BDRV_SECTOR_BITS);
 698    buf = qemu_opt_get_del(opts, PARALLELS_OPT_PREALLOC_MODE);
 699    s->prealloc_mode = qapi_enum_parse(prealloc_mode_lookup, buf,
 700            PRL_PREALLOC_MODE__MAX, PRL_PREALLOC_MODE_FALLOCATE, &local_err);
 701    g_free(buf);
 702    if (local_err != NULL) {
 703        goto fail_options;
 704    }
 705
 706    if (!bdrv_has_zero_init(bs->file->bs)) {
 707        s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE;
 708    }
 709
 710    if (flags & BDRV_O_RDWR) {
 711        s->header->inuse = cpu_to_le32(HEADER_INUSE_MAGIC);
 712        ret = parallels_update_header(bs);
 713        if (ret < 0) {
 714            goto fail;
 715        }
 716    }
 717
 718    s->bat_dirty_block = 4 * getpagesize();
 719    s->bat_dirty_bmap =
 720        bitmap_new(DIV_ROUND_UP(s->header_size, s->bat_dirty_block));
 721
 722    qemu_co_mutex_init(&s->lock);
 723    return 0;
 724
 725fail_format:
 726    error_setg(errp, "Image not in Parallels format");
 727    ret = -EINVAL;
 728fail:
 729    qemu_vfree(s->header);
 730    return ret;
 731
 732fail_options:
 733    error_propagate(errp, local_err);
 734    ret = -EINVAL;
 735    goto fail;
 736}
 737
 738
 739static void parallels_close(BlockDriverState *bs)
 740{
 741    BDRVParallelsState *s = bs->opaque;
 742
 743    if (bs->open_flags & BDRV_O_RDWR) {
 744        s->header->inuse = 0;
 745        parallels_update_header(bs);
 746    }
 747
 748    if (bs->open_flags & BDRV_O_RDWR) {
 749        bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS,
 750                      PREALLOC_MODE_OFF, NULL);
 751    }
 752
 753    g_free(s->bat_dirty_bmap);
 754    qemu_vfree(s->header);
 755}
 756
 757static QemuOptsList parallels_create_opts = {
 758    .name = "parallels-create-opts",
 759    .head = QTAILQ_HEAD_INITIALIZER(parallels_create_opts.head),
 760    .desc = {
 761        {
 762            .name = BLOCK_OPT_SIZE,
 763            .type = QEMU_OPT_SIZE,
 764            .help = "Virtual disk size",
 765        },
 766        {
 767            .name = BLOCK_OPT_CLUSTER_SIZE,
 768            .type = QEMU_OPT_SIZE,
 769            .help = "Parallels image cluster size",
 770            .def_value_str = stringify(DEFAULT_CLUSTER_SIZE),
 771        },
 772        { /* end of list */ }
 773    }
 774};
 775
 776static BlockDriver bdrv_parallels = {
 777    .format_name        = "parallels",
 778    .instance_size      = sizeof(BDRVParallelsState),
 779    .bdrv_probe         = parallels_probe,
 780    .bdrv_open          = parallels_open,
 781    .bdrv_close         = parallels_close,
 782    .bdrv_child_perm          = bdrv_format_default_perms,
 783    .bdrv_co_get_block_status = parallels_co_get_block_status,
 784    .bdrv_has_zero_init       = bdrv_has_zero_init_1,
 785    .bdrv_co_flush_to_os      = parallels_co_flush_to_os,
 786    .bdrv_co_readv  = parallels_co_readv,
 787    .bdrv_co_writev = parallels_co_writev,
 788
 789    .bdrv_create    = parallels_create,
 790    .bdrv_check     = parallels_check,
 791    .create_opts    = &parallels_create_opts,
 792};
 793
 794static void bdrv_parallels_init(void)
 795{
 796    bdrv_register(&bdrv_parallels);
 797}
 798
 799block_init(bdrv_parallels_init);
 800