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
  31 #include "qemu/osdep.h"
  32 #include "qemu/error-report.h"
  33 #include "qapi/error.h"
  34 #include "block/block_int.h"
  35 #include "block/qdict.h"
  36 #include "sysemu/block-backend.h"
  37 #include "qemu/module.h"
  38 #include "qemu/option.h"
  39 #include "qapi/qmp/qdict.h"
  40 #include "qapi/qobject-input-visitor.h"
  41 #include "qapi/qapi-visit-block-core.h"
  42 #include "qemu/bswap.h"
  43 #include "qemu/bitmap.h"
  44 #include "qemu/memalign.h"
  45 #include "migration/blocker.h"
  46 #include "parallels.h"
  47
  48 /**************************************************************/
  49
  50 #define HEADER_MAGIC "WithoutFreeSpace"
  51 #define HEADER_MAGIC2 "WithouFreSpacExt"
  52 #define HEADER_VERSION 2
  53 #define HEADER_INUSE_MAGIC  (0x746F6E59)
  54 #define MAX_PARALLELS_IMAGE_FACTOR (1ull << 32)
  55
  56 static QEnumLookup prealloc_mode_lookup = {
  57     .array = (const char *const[]) {
  58         "falloc",
  59         "truncate",
  60     },
  61     .size = PRL_PREALLOC_MODE__MAX
  62 };
  63
  64 #define PARALLELS_OPT_PREALLOC_MODE     "prealloc-mode"
  65 #define PARALLELS_OPT_PREALLOC_SIZE     "prealloc-size"
  66
  67 static QemuOptsList parallels_runtime_opts = {
  68     .name = "parallels",
  69     .head = QTAILQ_HEAD_INITIALIZER(parallels_runtime_opts.head),
  70     .desc = {
  71         {
  72             .name = PARALLELS_OPT_PREALLOC_SIZE,
  73             .type = QEMU_OPT_SIZE,
  74             .help = "Preallocation size on image expansion",
  75             .def_value_str = "128M",
  76         },
  77         {
  78             .name = PARALLELS_OPT_PREALLOC_MODE,
  79             .type = QEMU_OPT_STRING,
  80             .help = "Preallocation mode on image expansion "
  81                     "(allowed values: falloc, truncate)",
  82             .def_value_str = "falloc",
  83         },
  84         { /* end of list */ },
  85     },
  86 };
  87
  88 static QemuOptsList parallels_create_opts = {
  89     .name = "parallels-create-opts",
  90     .head = QTAILQ_HEAD_INITIALIZER(parallels_create_opts.head),
  91     .desc = {
  92         {
  93             .name = BLOCK_OPT_SIZE,
  94             .type = QEMU_OPT_SIZE,
  95             .help = "Virtual disk size",
  96         },
  97         {
  98             .name = BLOCK_OPT_CLUSTER_SIZE,
  99             .type = QEMU_OPT_SIZE,
 100             .help = "Parallels image cluster size",
 101             .def_value_str = stringify(DEFAULT_CLUSTER_SIZE),
 102         },
 103         { /* end of list */ }
 104     }
 105 };
 106
 107
 108 static int64_t bat2sect(BDRVParallelsState *s, uint32_t idx)
 109 {
 110     return (uint64_t)le32_to_cpu(s->bat_bitmap[idx]) * s->off_multiplier;
 111 }
 112
 113 static uint32_t bat_entry_off(uint32_t idx)
 114 {
 115     return sizeof(ParallelsHeader) + sizeof(uint32_t) * idx;
 116 }
 117
 118 static int64_t seek_to_sector(BDRVParallelsState *s, int64_t sector_num)
 119 {
 120     uint32_t index, offset;
 121
 122     index = sector_num / s->tracks;
 123     offset = sector_num % s->tracks;
 124
 125     /* not allocated */
 126     if ((index >= s->bat_size) || (s->bat_bitmap[index] == 0)) {
 127         return -1;
 128     }
 129     return bat2sect(s, index) + offset;
 130 }
 131
 132 static int cluster_remainder(BDRVParallelsState *s, int64_t sector_num,
 133         int nb_sectors)
 134 {
 135     int ret = s->tracks - sector_num % s->tracks;
 136     return MIN(nb_sectors, ret);
 137 }
 138
 139 static int64_t block_status(BDRVParallelsState *s, int64_t sector_num,
 140                             int nb_sectors, int *pnum)
 141 {
 142     int64_t start_off = -2, prev_end_off = -2;
 143
 144     *pnum = 0;
 145     while (nb_sectors > 0 || start_off == -2) {
 146         int64_t offset = seek_to_sector(s, sector_num);
 147         int to_end;
 148
 149         if (start_off == -2) {
 150             start_off = offset;
 151             prev_end_off = offset;
 152         } else if (offset != prev_end_off) {
 153             break;
 154         }
 155
 156         to_end = cluster_remainder(s, sector_num, nb_sectors);
 157         nb_sectors -= to_end;
 158         sector_num += to_end;
 159         *pnum += to_end;
 160
 161         if (offset > 0) {
 162             prev_end_off += to_end;
 163         }
 164     }
 165     return start_off;
 166 }
 167
 168 static int64_t coroutine_fn GRAPH_RDLOCK
 169 allocate_clusters(BlockDriverState *bs, int64_t sector_num,
 170                   int nb_sectors, int *pnum)
 171 {
 172     int ret = 0;
 173     BDRVParallelsState *s = bs->opaque;
 174     int64_t pos, space, idx, to_allocate, i, len;
 175
 176     pos = block_status(s, sector_num, nb_sectors, pnum);
 177     if (pos > 0) {
 178         return pos;
 179     }
 180
 181     idx = sector_num / s->tracks;
 182     to_allocate = DIV_ROUND_UP(sector_num + *pnum, s->tracks) - idx;
 183
 184     /* This function is called only by parallels_co_writev(), which will never
 185      * pass a sector_num at or beyond the end of the image (because the block
 186      * layer never passes such a sector_num to that function). Therefore, idx
 187      * is always below s->bat_size.
 188      * block_status() will limit *pnum so that sector_num + *pnum will not
 189      * exceed the image end. Therefore, idx + to_allocate cannot exceed
 190      * s->bat_size.
 191      * Note that s->bat_size is an unsigned int, therefore idx + to_allocate
 192      * will always fit into a uint32_t. */
 193     assert(idx < s->bat_size && idx + to_allocate <= s->bat_size);
 194
 195     space = to_allocate * s->tracks;
 196     len = bdrv_getlength(bs->file->bs);
 197     if (len < 0) {
 198         return len;
 199     }
 200     if (s->data_end + space > (len >> BDRV_SECTOR_BITS)) {
 201         space += s->prealloc_size;
 202         /*
 203          * We require the expanded size to read back as zero. If the
 204          * user permitted truncation, we try that; but if it fails, we
 205          * force the safer-but-slower fallocate.
 206          */
 207         if (s->prealloc_mode == PRL_PREALLOC_MODE_TRUNCATE) {
 208             ret = bdrv_co_truncate(bs->file,
 209                                    (s->data_end + space) << BDRV_SECTOR_BITS,
 210                                    false, PREALLOC_MODE_OFF,
 211                                    BDRV_REQ_ZERO_WRITE, NULL);
 212             if (ret == -ENOTSUP) {
 213                 s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE;
 214             }
 215         }
 216         if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) {
 217             ret = bdrv_co_pwrite_zeroes(bs->file,
 218                                         s->data_end << BDRV_SECTOR_BITS,
 219                                         space << BDRV_SECTOR_BITS, 0);
 220         }
 221         if (ret < 0) {
 222             return ret;
 223         }
 224     }
 225
 226     /* Try to read from backing to fill empty clusters
 227      * FIXME: 1. previous write_zeroes may be redundant
 228      *        2. most of data we read from backing will be rewritten by
 229      *           parallels_co_writev. On aligned-to-cluster write we do not need
 230      *           this read at all.
 231      *        3. it would be good to combine write of data from backing and new
 232      *           data into one write call */
 233     if (bs->backing) {
 234         int64_t nb_cow_sectors = to_allocate * s->tracks;
 235         int64_t nb_cow_bytes = nb_cow_sectors << BDRV_SECTOR_BITS;
 236         void *buf = qemu_blockalign(bs, nb_cow_bytes);
 237
 238         ret = bdrv_co_pread(bs->backing, idx * s->tracks * BDRV_SECTOR_SIZE,
 239                             nb_cow_bytes, buf, 0);
 240         if (ret < 0) {
 241             qemu_vfree(buf);
 242             return ret;
 243         }
 244
 245         ret = bdrv_co_pwrite(bs->file, s->data_end * BDRV_SECTOR_SIZE,
 246                              nb_cow_bytes, buf, 0);
 247         qemu_vfree(buf);
 248         if (ret < 0) {
 249             return ret;
 250         }
 251     }
 252
 253     for (i = 0; i < to_allocate; i++) {
 254         s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier);
 255         s->data_end += s->tracks;
 256         bitmap_set(s->bat_dirty_bmap,
 257                    bat_entry_off(idx + i) / s->bat_dirty_block, 1);
 258     }
 259
 260     return bat2sect(s, idx) + sector_num % s->tracks;
 261 }
 262
 263
 264 static int coroutine_fn GRAPH_RDLOCK
 265 parallels_co_flush_to_os(BlockDriverState *bs)
 266 {
 267     BDRVParallelsState *s = bs->opaque;
 268     unsigned long size = DIV_ROUND_UP(s->header_size, s->bat_dirty_block);
 269     unsigned long bit;
 270
 271     qemu_co_mutex_lock(&s->lock);
 272
 273     bit = find_first_bit(s->bat_dirty_bmap, size);
 274     while (bit < size) {
 275         uint32_t off = bit * s->bat_dirty_block;
 276         uint32_t to_write = s->bat_dirty_block;
 277         int ret;
 278
 279         if (off + to_write > s->header_size) {
 280             to_write = s->header_size - off;
 281         }
 282         ret = bdrv_co_pwrite(bs->file, off, to_write,
 283                              (uint8_t *)s->header + off, 0);
 284         if (ret < 0) {
 285             qemu_co_mutex_unlock(&s->lock);
 286             return ret;
 287         }
 288         bit = find_next_bit(s->bat_dirty_bmap, size, bit + 1);
 289     }
 290     bitmap_zero(s->bat_dirty_bmap, size);
 291
 292     qemu_co_mutex_unlock(&s->lock);
 293     return 0;
 294 }
 295
 296
 297 static int coroutine_fn parallels_co_block_status(BlockDriverState *bs,
 298                                                   bool want_zero,
 299                                                   int64_t offset,
 300                                                   int64_t bytes,
 301                                                   int64_t *pnum,
 302                                                   int64_t *map,
 303                                                   BlockDriverState **file)
 304 {
 305     BDRVParallelsState *s = bs->opaque;
 306     int count;
 307
 308     assert(QEMU_IS_ALIGNED(offset | bytes, BDRV_SECTOR_SIZE));
 309     qemu_co_mutex_lock(&s->lock);
 310     offset = block_status(s, offset >> BDRV_SECTOR_BITS,
 311                           bytes >> BDRV_SECTOR_BITS, &count);
 312     qemu_co_mutex_unlock(&s->lock);
 313
 314     *pnum = count * BDRV_SECTOR_SIZE;
 315     if (offset < 0) {
 316         return 0;
 317     }
 318
 319     *map = offset * BDRV_SECTOR_SIZE;
 320     *file = bs->file->bs;
 321     return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
 322 }
 323
 324 static int coroutine_fn GRAPH_RDLOCK
 325 parallels_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 326                     QEMUIOVector *qiov, int flags)
 327 {
 328     BDRVParallelsState *s = bs->opaque;
 329     uint64_t bytes_done = 0;
 330     QEMUIOVector hd_qiov;
 331     int ret = 0;
 332
 333     qemu_iovec_init(&hd_qiov, qiov->niov);
 334
 335     while (nb_sectors > 0) {
 336         int64_t position;
 337         int n, nbytes;
 338
 339         qemu_co_mutex_lock(&s->lock);
 340         position = allocate_clusters(bs, sector_num, nb_sectors, &n);
 341         qemu_co_mutex_unlock(&s->lock);
 342         if (position < 0) {
 343             ret = (int)position;
 344             break;
 345         }
 346
 347         nbytes = n << BDRV_SECTOR_BITS;
 348
 349         qemu_iovec_reset(&hd_qiov);
 350         qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);
 351
 352         ret = bdrv_co_pwritev(bs->file, position * BDRV_SECTOR_SIZE, nbytes,
 353                               &hd_qiov, 0);
 354         if (ret < 0) {
 355             break;
 356         }
 357
 358         nb_sectors -= n;
 359         sector_num += n;
 360         bytes_done += nbytes;
 361     }
 362
 363     qemu_iovec_destroy(&hd_qiov);
 364     return ret;
 365 }
 366
 367 static int coroutine_fn GRAPH_RDLOCK
 368 parallels_co_readv(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 369                    QEMUIOVector *qiov)
 370 {
 371     BDRVParallelsState *s = bs->opaque;
 372     uint64_t bytes_done = 0;
 373     QEMUIOVector hd_qiov;
 374     int ret = 0;
 375
 376     qemu_iovec_init(&hd_qiov, qiov->niov);
 377
 378     while (nb_sectors > 0) {
 379         int64_t position;
 380         int n, nbytes;
 381
 382         qemu_co_mutex_lock(&s->lock);
 383         position = block_status(s, sector_num, nb_sectors, &n);
 384         qemu_co_mutex_unlock(&s->lock);
 385
 386         nbytes = n << BDRV_SECTOR_BITS;
 387
 388         qemu_iovec_reset(&hd_qiov);
 389         qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);
 390
 391         if (position < 0) {
 392             if (bs->backing) {
 393                 ret = bdrv_co_preadv(bs->backing, sector_num * BDRV_SECTOR_SIZE,
 394                                      nbytes, &hd_qiov, 0);
 395                 if (ret < 0) {
 396                     break;
 397                 }
 398             } else {
 399                 qemu_iovec_memset(&hd_qiov, 0, 0, nbytes);
 400             }
 401         } else {
 402             ret = bdrv_co_preadv(bs->file, position * BDRV_SECTOR_SIZE, nbytes,
 403                                  &hd_qiov, 0);
 404             if (ret < 0) {
 405                 break;
 406             }
 407         }
 408
 409         nb_sectors -= n;
 410         sector_num += n;
 411         bytes_done += nbytes;
 412     }
 413
 414     qemu_iovec_destroy(&hd_qiov);
 415     return ret;
 416 }
 417
 418
 419 static int coroutine_fn GRAPH_RDLOCK
 420 parallels_co_check(BlockDriverState *bs, BdrvCheckResult *res,
 421                    BdrvCheckMode fix)
 422 {
 423     BDRVParallelsState *s = bs->opaque;
 424     int64_t size, prev_off, high_off;
 425     int ret;
 426     uint32_t i;
 427     bool flush_bat = false;
 428
 429     size = bdrv_getlength(bs->file->bs);
 430     if (size < 0) {
 431         res->check_errors++;
 432         return size;
 433     }
 434
 435     qemu_co_mutex_lock(&s->lock);
 436     if (s->header_unclean) {
 437         fprintf(stderr, "%s image was not closed correctly\n",
 438                 fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR");
 439         res->corruptions++;
 440         if (fix & BDRV_FIX_ERRORS) {
 441             /* parallels_close will do the job right */
 442             res->corruptions_fixed++;
 443             s->header_unclean = false;
 444         }
 445     }
 446
 447     res->bfi.total_clusters = s->bat_size;
 448     res->bfi.compressed_clusters = 0; /* compression is not supported */
 449
 450     high_off = 0;
 451     prev_off = 0;
 452     for (i = 0; i < s->bat_size; i++) {
 453         int64_t off = bat2sect(s, i) << BDRV_SECTOR_BITS;
 454         if (off == 0) {
 455             prev_off = 0;
 456             continue;
 457         }
 458
 459         /* cluster outside the image */
 460         if (off > size) {
 461             fprintf(stderr, "%s cluster %u is outside image\n",
 462                     fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", i);
 463             res->corruptions++;
 464             if (fix & BDRV_FIX_ERRORS) {
 465                 prev_off = 0;
 466                 s->bat_bitmap[i] = 0;
 467                 res->corruptions_fixed++;
 468                 flush_bat = true;
 469                 continue;
 470             }
 471         }
 472
 473         res->bfi.allocated_clusters++;
 474         if (off > high_off) {
 475             high_off = off;
 476         }
 477
 478         if (prev_off != 0 && (prev_off + s->cluster_size) != off) {
 479             res->bfi.fragmented_clusters++;
 480         }
 481         prev_off = off;
 482     }
 483
 484     ret = 0;
 485     if (flush_bat) {
 486         ret = bdrv_co_pwrite_sync(bs->file, 0, s->header_size, s->header, 0);
 487         if (ret < 0) {
 488             res->check_errors++;
 489             goto out;
 490         }
 491     }
 492
 493     res->image_end_offset = high_off + s->cluster_size;
 494     if (size > res->image_end_offset) {
 495         int64_t count;
 496         count = DIV_ROUND_UP(size - res->image_end_offset, s->cluster_size);
 497         fprintf(stderr, "%s space leaked at the end of the image %" PRId64 "\n",
 498                 fix & BDRV_FIX_LEAKS ? "Repairing" : "ERROR",
 499                 size - res->image_end_offset);
 500         res->leaks += count;
 501         if (fix & BDRV_FIX_LEAKS) {
 502             Error *local_err = NULL;
 503
 504             /*
 505              * In order to really repair the image, we must shrink it.
 506              * That means we have to pass exact=true.
 507              */
 508             ret = bdrv_co_truncate(bs->file, res->image_end_offset, true,
 509                                    PREALLOC_MODE_OFF, 0, &local_err);
 510             if (ret < 0) {
 511                 error_report_err(local_err);
 512                 res->check_errors++;
 513                 goto out;
 514             }
 515             res->leaks_fixed += count;
 516         }
 517     }
 518
 519 out:
 520     qemu_co_mutex_unlock(&s->lock);
 521     return ret;
 522 }
 523
 524
 525 static int coroutine_fn parallels_co_create(BlockdevCreateOptions* opts,
 526                                             Error **errp)
 527 {
 528     BlockdevCreateOptionsParallels *parallels_opts;
 529     BlockDriverState *bs;
 530     BlockBackend *blk;
 531     int64_t total_size, cl_size;
 532     uint32_t bat_entries, bat_sectors;
 533     ParallelsHeader header;
 534     uint8_t tmp[BDRV_SECTOR_SIZE];
 535     int ret;
 536
 537     assert(opts->driver == BLOCKDEV_DRIVER_PARALLELS);
 538     parallels_opts = &opts->u.parallels;
 539
 540     /* Sanity checks */
 541     total_size = parallels_opts->size;
 542
 543     if (parallels_opts->has_cluster_size) {
 544         cl_size = parallels_opts->cluster_size;
 545     } else {
 546         cl_size = DEFAULT_CLUSTER_SIZE;
 547     }
 548
 549     /* XXX What is the real limit here? This is an insanely large maximum. */
 550     if (cl_size >= INT64_MAX / MAX_PARALLELS_IMAGE_FACTOR) {
 551         error_setg(errp, "Cluster size is too large");
 552         return -EINVAL;
 553     }
 554     if (total_size >= MAX_PARALLELS_IMAGE_FACTOR * cl_size) {
 555         error_setg(errp, "Image size is too large for this cluster size");
 556         return -E2BIG;
 557     }
 558
 559     if (!QEMU_IS_ALIGNED(total_size, BDRV_SECTOR_SIZE)) {
 560         error_setg(errp, "Image size must be a multiple of 512 bytes");
 561         return -EINVAL;
 562     }
 563
 564     if (!QEMU_IS_ALIGNED(cl_size, BDRV_SECTOR_SIZE)) {
 565         error_setg(errp, "Cluster size must be a multiple of 512 bytes");
 566         return -EINVAL;
 567     }
 568
 569     /* Create BlockBackend to write to the image */
 570     bs = bdrv_co_open_blockdev_ref(parallels_opts->file, errp);
 571     if (bs == NULL) {
 572         return -EIO;
 573     }
 574
 575     blk = blk_co_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
 576                              errp);
 577     if (!blk) {
 578         ret = -EPERM;
 579         goto out;
 580     }
 581     blk_set_allow_write_beyond_eof(blk, true);
 582
 583     /* Create image format */
 584     bat_entries = DIV_ROUND_UP(total_size, cl_size);
 585     bat_sectors = DIV_ROUND_UP(bat_entry_off(bat_entries), cl_size);
 586     bat_sectors = (bat_sectors *  cl_size) >> BDRV_SECTOR_BITS;
 587
 588     memset(&header, 0, sizeof(header));
 589     memcpy(header.magic, HEADER_MAGIC2, sizeof(header.magic));
 590     header.version = cpu_to_le32(HEADER_VERSION);
 591     /* don't care much about geometry, it is not used on image level */
 592     header.heads = cpu_to_le32(HEADS_NUMBER);
 593     header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE
 594                                    / HEADS_NUMBER / SEC_IN_CYL);
 595     header.tracks = cpu_to_le32(cl_size >> BDRV_SECTOR_BITS);
 596     header.bat_entries = cpu_to_le32(bat_entries);
 597     header.nb_sectors = cpu_to_le64(DIV_ROUND_UP(total_size, BDRV_SECTOR_SIZE));
 598     header.data_off = cpu_to_le32(bat_sectors);
 599
 600     /* write all the data */
 601     memset(tmp, 0, sizeof(tmp));
 602     memcpy(tmp, &header, sizeof(header));
 603
 604     ret = blk_co_pwrite(blk, 0, BDRV_SECTOR_SIZE, tmp, 0);
 605     if (ret < 0) {
 606         goto exit;
 607     }
 608     ret = blk_co_pwrite_zeroes(blk, BDRV_SECTOR_SIZE,
 609                                (bat_sectors - 1) << BDRV_SECTOR_BITS, 0);
 610     if (ret < 0) {
 611         goto exit;
 612     }
 613
 614     ret = 0;
 615 out:
 616     blk_unref(blk);
 617     bdrv_unref(bs);
 618     return ret;
 619
 620 exit:
 621     error_setg_errno(errp, -ret, "Failed to create Parallels image");
 622     goto out;
 623 }
 624
 625 static int coroutine_fn GRAPH_RDLOCK
 626 parallels_co_create_opts(BlockDriver *drv, const char *filename,
 627                          QemuOpts *opts, Error **errp)
 628 {
 629     BlockdevCreateOptions *create_options = NULL;
 630     BlockDriverState *bs = NULL;
 631     QDict *qdict;
 632     Visitor *v;
 633     int ret;
 634
 635     static const QDictRenames opt_renames[] = {
 636         { BLOCK_OPT_CLUSTER_SIZE,       "cluster-size" },
 637         { NULL, NULL },
 638     };
 639
 640     /* Parse options and convert legacy syntax */
 641     qdict = qemu_opts_to_qdict_filtered(opts, NULL, &parallels_create_opts,
 642                                         true);
 643
 644     if (!qdict_rename_keys(qdict, opt_renames, errp)) {
 645         ret = -EINVAL;
 646         goto done;
 647     }
 648
 649     /* Create and open the file (protocol layer) */
 650     ret = bdrv_co_create_file(filename, opts, errp);
 651     if (ret < 0) {
 652         goto done;
 653     }
 654
 655     bs = bdrv_co_open(filename, NULL, NULL,
 656                       BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp);
 657     if (bs == NULL) {
 658         ret = -EIO;
 659         goto done;
 660     }
 661
 662     /* Now get the QAPI type BlockdevCreateOptions */
 663     qdict_put_str(qdict, "driver", "parallels");
 664     qdict_put_str(qdict, "file", bs->node_name);
 665
 666     v = qobject_input_visitor_new_flat_confused(qdict, errp);
 667     if (!v) {
 668         ret = -EINVAL;
 669         goto done;
 670     }
 671
 672     visit_type_BlockdevCreateOptions(v, NULL, &create_options, errp);
 673     visit_free(v);
 674     if (!create_options) {
 675         ret = -EINVAL;
 676         goto done;
 677     }
 678
 679     /* Silently round up sizes */
 680     create_options->u.parallels.size =
 681         ROUND_UP(create_options->u.parallels.size, BDRV_SECTOR_SIZE);
 682     create_options->u.parallels.cluster_size =
 683         ROUND_UP(create_options->u.parallels.cluster_size, BDRV_SECTOR_SIZE);
 684
 685     /* Create the Parallels image (format layer) */
 686     ret = parallels_co_create(create_options, errp);
 687     if (ret < 0) {
 688         goto done;
 689     }
 690     ret = 0;
 691
 692 done:
 693     qobject_unref(qdict);
 694     bdrv_unref(bs);
 695     qapi_free_BlockdevCreateOptions(create_options);
 696     return ret;
 697 }
 698
 699
 700 static int parallels_probe(const uint8_t *buf, int buf_size,
 701                            const char *filename)
 702 {
 703     const ParallelsHeader *ph = (const void *)buf;
 704
 705     if (buf_size < sizeof(ParallelsHeader)) {
 706         return 0;
 707     }
 708
 709     if ((!memcmp(ph->magic, HEADER_MAGIC, 16) ||
 710            !memcmp(ph->magic, HEADER_MAGIC2, 16)) &&
 711            (le32_to_cpu(ph->version) == HEADER_VERSION)) {
 712         return 100;
 713     }
 714
 715     return 0;
 716 }
 717
 718 static int parallels_update_header(BlockDriverState *bs)
 719 {
 720     BDRVParallelsState *s = bs->opaque;
 721     unsigned size = MAX(bdrv_opt_mem_align(bs->file->bs),
 722                         sizeof(ParallelsHeader));
 723
 724     if (size > s->header_size) {
 725         size = s->header_size;
 726     }
 727     return bdrv_pwrite_sync(bs->file, 0, size, s->header, 0);
 728 }
 729
 730 static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
 731                           Error **errp)
 732 {
 733     BDRVParallelsState *s = bs->opaque;
 734     ParallelsHeader ph;
 735     int ret, size, i;
 736     QemuOpts *opts = NULL;
 737     Error *local_err = NULL;
 738     char *buf;
 739
 740     ret = bdrv_open_file_child(NULL, options, "file", bs, errp);
 741     if (ret < 0) {
 742         return ret;
 743     }
 744
 745     ret = bdrv_pread(bs->file, 0, sizeof(ph), &ph, 0);
 746     if (ret < 0) {
 747         goto fail;
 748     }
 749
 750     bs->total_sectors = le64_to_cpu(ph.nb_sectors);
 751
 752     if (le32_to_cpu(ph.version) != HEADER_VERSION) {
 753         goto fail_format;
 754     }
 755     if (!memcmp(ph.magic, HEADER_MAGIC, 16)) {
 756         s->off_multiplier = 1;
 757         bs->total_sectors = 0xffffffff & bs->total_sectors;
 758     } else if (!memcmp(ph.magic, HEADER_MAGIC2, 16)) {
 759         s->off_multiplier = le32_to_cpu(ph.tracks);
 760     } else {
 761         goto fail_format;
 762     }
 763
 764     s->tracks = le32_to_cpu(ph.tracks);
 765     if (s->tracks == 0) {
 766         error_setg(errp, "Invalid image: Zero sectors per track");
 767         ret = -EINVAL;
 768         goto fail;
 769     }
 770     if (s->tracks > INT32_MAX/513) {
 771         error_setg(errp, "Invalid image: Too big cluster");
 772         ret = -EFBIG;
 773         goto fail;
 774     }
 775     s->cluster_size = s->tracks << BDRV_SECTOR_BITS;
 776
 777     s->bat_size = le32_to_cpu(ph.bat_entries);
 778     if (s->bat_size > INT_MAX / sizeof(uint32_t)) {
 779         error_setg(errp, "Catalog too large");
 780         ret = -EFBIG;
 781         goto fail;
 782     }
 783
 784     size = bat_entry_off(s->bat_size);
 785     s->header_size = ROUND_UP(size, bdrv_opt_mem_align(bs->file->bs));
 786     s->header = qemu_try_blockalign(bs->file->bs, s->header_size);
 787     if (s->header == NULL) {
 788         ret = -ENOMEM;
 789         goto fail;
 790     }
 791     s->data_end = le32_to_cpu(ph.data_off);
 792     if (s->data_end == 0) {
 793         s->data_end = ROUND_UP(bat_entry_off(s->bat_size), BDRV_SECTOR_SIZE);
 794     }
 795     if (s->data_end < s->header_size) {
 796         /* there is not enough unused space to fit to block align between BAT
 797            and actual data. We can't avoid read-modify-write... */
 798         s->header_size = size;
 799     }
 800
 801     ret = bdrv_pread(bs->file, 0, s->header_size, s->header, 0);
 802     if (ret < 0) {
 803         goto fail;
 804     }
 805     s->bat_bitmap = (uint32_t *)(s->header + 1);
 806
 807     for (i = 0; i < s->bat_size; i++) {
 808         int64_t off = bat2sect(s, i);
 809         if (off >= s->data_end) {
 810             s->data_end = off + s->tracks;
 811         }
 812     }
 813
 814     if (le32_to_cpu(ph.inuse) == HEADER_INUSE_MAGIC) {
 815         /* Image was not closed correctly. The check is mandatory */
 816         s->header_unclean = true;
 817         if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) {
 818             error_setg(errp, "parallels: Image was not closed correctly; "
 819                        "cannot be opened read/write");
 820             ret = -EACCES;
 821             goto fail;
 822         }
 823     }
 824
 825     opts = qemu_opts_create(&parallels_runtime_opts, NULL, 0, errp);
 826     if (!opts) {
 827         goto fail_options;
 828     }
 829
 830     if (!qemu_opts_absorb_qdict(opts, options, errp)) {
 831         goto fail_options;
 832     }
 833
 834     s->prealloc_size =
 835         qemu_opt_get_size_del(opts, PARALLELS_OPT_PREALLOC_SIZE, 0);
 836     s->prealloc_size = MAX(s->tracks, s->prealloc_size >> BDRV_SECTOR_BITS);
 837     buf = qemu_opt_get_del(opts, PARALLELS_OPT_PREALLOC_MODE);
 838     /* prealloc_mode can be downgraded later during allocate_clusters */
 839     s->prealloc_mode = qapi_enum_parse(&prealloc_mode_lookup, buf,
 840                                        PRL_PREALLOC_MODE_FALLOCATE,
 841                                        &local_err);
 842     g_free(buf);
 843     if (local_err != NULL) {
 844         error_propagate(errp, local_err);
 845         goto fail_options;
 846     }
 847
 848     if (ph.ext_off) {
 849         if (flags & BDRV_O_RDWR) {
 850             /*
 851              * It's unsafe to open image RW if there is an extension (as we
 852              * don't support it). But parallels driver in QEMU historically
 853              * ignores the extension, so print warning and don't care.
 854              */
 855             warn_report("Format Extension ignored in RW mode");
 856         } else {
 857             ret = parallels_read_format_extension(
 858                     bs, le64_to_cpu(ph.ext_off) << BDRV_SECTOR_BITS, errp);
 859             if (ret < 0) {
 860                 goto fail;
 861             }
 862         }
 863     }
 864
 865     if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_INACTIVE)) {
 866         s->header->inuse = cpu_to_le32(HEADER_INUSE_MAGIC);
 867         ret = parallels_update_header(bs);
 868         if (ret < 0) {
 869             goto fail;
 870         }
 871     }
 872
 873     s->bat_dirty_block = 4 * qemu_real_host_page_size();
 874     s->bat_dirty_bmap =
 875         bitmap_new(DIV_ROUND_UP(s->header_size, s->bat_dirty_block));
 876
 877     /* Disable migration until bdrv_activate method is added */
 878     error_setg(&s->migration_blocker, "The Parallels format used by node '%s' "
 879                "does not support live migration",
 880                bdrv_get_device_or_node_name(bs));
 881     ret = migrate_add_blocker(s->migration_blocker, errp);
 882     if (ret < 0) {
 883         error_free(s->migration_blocker);
 884         goto fail;
 885     }
 886     qemu_co_mutex_init(&s->lock);
 887     return 0;
 888
 889 fail_format:
 890     error_setg(errp, "Image not in Parallels format");
 891 fail_options:
 892     ret = -EINVAL;
 893 fail:
 894     qemu_vfree(s->header);
 895     return ret;
 896 }
 897
 898
 899 static void parallels_close(BlockDriverState *bs)
 900 {
 901     BDRVParallelsState *s = bs->opaque;
 902
 903     if ((bs->open_flags & BDRV_O_RDWR) && !(bs->open_flags & BDRV_O_INACTIVE)) {
 904         s->header->inuse = 0;
 905         parallels_update_header(bs);
 906
 907         /* errors are ignored, so we might as well pass exact=true */
 908         bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS, true,
 909                       PREALLOC_MODE_OFF, 0, NULL);
 910     }
 911
 912     g_free(s->bat_dirty_bmap);
 913     qemu_vfree(s->header);
 914
 915     migrate_del_blocker(s->migration_blocker);
 916     error_free(s->migration_blocker);
 917 }
 918
 919 static BlockDriver bdrv_parallels = {
 920     .format_name        = "parallels",
 921     .instance_size      = sizeof(BDRVParallelsState),
 922     .bdrv_probe         = parallels_probe,
 923     .bdrv_open          = parallels_open,
 924     .bdrv_close         = parallels_close,
 925     .bdrv_child_perm          = bdrv_default_perms,
 926     .bdrv_co_block_status     = parallels_co_block_status,
 927     .bdrv_has_zero_init       = bdrv_has_zero_init_1,
 928     .bdrv_co_flush_to_os      = parallels_co_flush_to_os,
 929     .bdrv_co_readv  = parallels_co_readv,
 930     .bdrv_co_writev = parallels_co_writev,
 931     .is_format      = true,
 932     .supports_backing = true,
 933     .bdrv_co_create      = parallels_co_create,
 934     .bdrv_co_create_opts = parallels_co_create_opts,
 935     .bdrv_co_check  = parallels_co_check,
 936     .create_opts    = &parallels_create_opts,
 937 };
 938
 939 static void bdrv_parallels_init(void)
 940 {
 941     bdrv_register(&bdrv_parallels);
 942 }
 943
 944 block_init(bdrv_parallels_init);