block/file-win32.c

   1 /*
   2  * Block driver for RAW files (win32)
   3  *
   4  * Copyright (c) 2006 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "qapi/error.h"
  27 #include "qemu/cutils.h"
  28 #include "block/block_int.h"
  29 #include "qemu/module.h"
  30 #include "qemu/option.h"
  31 #include "block/raw-aio.h"
  32 #include "trace.h"
  33 #include "block/thread-pool.h"
  34 #include "qemu/iov.h"
  35 #include "qapi/qmp/qdict.h"
  36 #include "qapi/qmp/qstring.h"
  37 #include <windows.h>
  38 #include <winioctl.h>
  39
  40 #define FTYPE_FILE 0
  41 #define FTYPE_CD     1
  42 #define FTYPE_HARDDISK 2
  43
  44 typedef struct RawWin32AIOData {
  45     BlockDriverState *bs;
  46     HANDLE hfile;
  47     struct iovec *aio_iov;
  48     int aio_niov;
  49     size_t aio_nbytes;
  50     off64_t aio_offset;
  51     int aio_type;
  52 } RawWin32AIOData;
  53
  54 typedef struct BDRVRawState {
  55     HANDLE hfile;
  56     int type;
  57     char drive_path[16]; /* format: "d:\" */
  58     QEMUWin32AIOState *aio;
  59 } BDRVRawState;
  60
  61 /*
  62  * Read/writes the data to/from a given linear buffer.
  63  *
  64  * Returns the number of bytes handles or -errno in case of an error. Short
  65  * reads are only returned if the end of the file is reached.
  66  */
  67 static size_t handle_aiocb_rw(RawWin32AIOData *aiocb)
  68 {
  69     size_t offset = 0;
  70     int i;
  71
  72     for (i = 0; i < aiocb->aio_niov; i++) {
  73         OVERLAPPED ov;
  74         DWORD ret, ret_count, len;
  75
  76         memset(&ov, 0, sizeof(ov));
  77         ov.Offset = (aiocb->aio_offset + offset);
  78         ov.OffsetHigh = (aiocb->aio_offset + offset) >> 32;
  79         len = aiocb->aio_iov[i].iov_len;
  80         if (aiocb->aio_type & QEMU_AIO_WRITE) {
  81             ret = WriteFile(aiocb->hfile, aiocb->aio_iov[i].iov_base,
  82                             len, &ret_count, &ov);
  83         } else {
  84             ret = ReadFile(aiocb->hfile, aiocb->aio_iov[i].iov_base,
  85                            len, &ret_count, &ov);
  86         }
  87         if (!ret) {
  88             ret_count = 0;
  89         }
  90         if (ret_count != len) {
  91             offset += ret_count;
  92             break;
  93         }
  94         offset += len;
  95     }
  96
  97     return offset;
  98 }
  99
 100 static int aio_worker(void *arg)
 101 {
 102     RawWin32AIOData *aiocb = arg;
 103     ssize_t ret = 0;
 104     size_t count;
 105
 106     switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
 107     case QEMU_AIO_READ:
 108         count = handle_aiocb_rw(aiocb);
 109         if (count < aiocb->aio_nbytes) {
 110             /* A short read means that we have reached EOF. Pad the buffer
 111              * with zeros for bytes after EOF. */
 112             iov_memset(aiocb->aio_iov, aiocb->aio_niov, count,
 113                       0, aiocb->aio_nbytes - count);
 114
 115             count = aiocb->aio_nbytes;
 116         }
 117         if (count == aiocb->aio_nbytes) {
 118             ret = 0;
 119         } else {
 120             ret = -EINVAL;
 121         }
 122         break;
 123     case QEMU_AIO_WRITE:
 124         count = handle_aiocb_rw(aiocb);
 125         if (count == aiocb->aio_nbytes) {
 126             ret = 0;
 127         } else {
 128             ret = -EINVAL;
 129         }
 130         break;
 131     case QEMU_AIO_FLUSH:
 132         if (!FlushFileBuffers(aiocb->hfile)) {
 133             return -EIO;
 134         }
 135         break;
 136     default:
 137         fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
 138         ret = -EINVAL;
 139         break;
 140     }
 141
 142     g_free(aiocb);
 143     return ret;
 144 }
 145
 146 static BlockAIOCB *paio_submit(BlockDriverState *bs, HANDLE hfile,
 147         int64_t offset, QEMUIOVector *qiov, int count,
 148         BlockCompletionFunc *cb, void *opaque, int type)
 149 {
 150     RawWin32AIOData *acb = g_new(RawWin32AIOData, 1);
 151     ThreadPool *pool;
 152
 153     acb->bs = bs;
 154     acb->hfile = hfile;
 155     acb->aio_type = type;
 156
 157     if (qiov) {
 158         acb->aio_iov = qiov->iov;
 159         acb->aio_niov = qiov->niov;
 160         assert(qiov->size == count);
 161     }
 162     acb->aio_nbytes = count;
 163     acb->aio_offset = offset;
 164
 165     trace_file_paio_submit(acb, opaque, offset, count, type);
 166     pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
 167     return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
 168 }
 169
 170 int qemu_ftruncate64(int fd, int64_t length)
 171 {
 172     LARGE_INTEGER li;
 173     DWORD dw;
 174     LONG high;
 175     HANDLE h;
 176     BOOL res;
 177
 178     if ((GetVersion() & 0x80000000UL) && (length >> 32) != 0)
 179         return -1;
 180
 181     h = (HANDLE)_get_osfhandle(fd);
 182
 183     /* get current position, ftruncate do not change position */
 184     li.HighPart = 0;
 185     li.LowPart = SetFilePointer (h, 0, &li.HighPart, FILE_CURRENT);
 186     if (li.LowPart == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
 187         return -1;
 188     }
 189
 190     high = length >> 32;
 191     dw = SetFilePointer(h, (DWORD) length, &high, FILE_BEGIN);
 192     if (dw == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
 193         return -1;
 194     }
 195     res = SetEndOfFile(h);
 196
 197     /* back to old position */
 198     SetFilePointer(h, li.LowPart, &li.HighPart, FILE_BEGIN);
 199     return res ? 0 : -1;
 200 }
 201
 202 static int set_sparse(int fd)
 203 {
 204     DWORD returned;
 205     return (int) DeviceIoControl((HANDLE)_get_osfhandle(fd), FSCTL_SET_SPARSE,
 206                                  NULL, 0, NULL, 0, &returned, NULL);
 207 }
 208
 209 static void raw_detach_aio_context(BlockDriverState *bs)
 210 {
 211     BDRVRawState *s = bs->opaque;
 212
 213     if (s->aio) {
 214         win32_aio_detach_aio_context(s->aio, bdrv_get_aio_context(bs));
 215     }
 216 }
 217
 218 static void raw_attach_aio_context(BlockDriverState *bs,
 219                                    AioContext *new_context)
 220 {
 221     BDRVRawState *s = bs->opaque;
 222
 223     if (s->aio) {
 224         win32_aio_attach_aio_context(s->aio, new_context);
 225     }
 226 }
 227
 228 static void raw_probe_alignment(BlockDriverState *bs, Error **errp)
 229 {
 230     BDRVRawState *s = bs->opaque;
 231     DWORD sectorsPerCluster, freeClusters, totalClusters, count;
 232     DISK_GEOMETRY_EX dg;
 233     BOOL status;
 234
 235     if (s->type == FTYPE_CD) {
 236         bs->bl.request_alignment = 2048;
 237         return;
 238     }
 239     if (s->type == FTYPE_HARDDISK) {
 240         status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
 241                                  NULL, 0, &dg, sizeof(dg), &count, NULL);
 242         if (status != 0) {
 243             bs->bl.request_alignment = dg.Geometry.BytesPerSector;
 244             return;
 245         }
 246         /* try GetDiskFreeSpace too */
 247     }
 248
 249     if (s->drive_path[0]) {
 250         GetDiskFreeSpace(s->drive_path, &sectorsPerCluster,
 251                          &dg.Geometry.BytesPerSector,
 252                          &freeClusters, &totalClusters);
 253         bs->bl.request_alignment = dg.Geometry.BytesPerSector;
 254         return;
 255     }
 256
 257     /* XXX Does Windows support AIO on less than 512-byte alignment? */
 258     bs->bl.request_alignment = 512;
 259 }
 260
 261 static void raw_parse_flags(int flags, bool use_aio, int *access_flags,
 262                             DWORD *overlapped)
 263 {
 264     assert(access_flags != NULL);
 265     assert(overlapped != NULL);
 266
 267     if (flags & BDRV_O_RDWR) {
 268         *access_flags = GENERIC_READ | GENERIC_WRITE;
 269     } else {
 270         *access_flags = GENERIC_READ;
 271     }
 272
 273     *overlapped = FILE_ATTRIBUTE_NORMAL;
 274     if (use_aio) {
 275         *overlapped |= FILE_FLAG_OVERLAPPED;
 276     }
 277     if (flags & BDRV_O_NOCACHE) {
 278         *overlapped |= FILE_FLAG_NO_BUFFERING;
 279     }
 280 }
 281
 282 static void raw_parse_filename(const char *filename, QDict *options,
 283                                Error **errp)
 284 {
 285     bdrv_parse_filename_strip_prefix(filename, "file:", options);
 286 }
 287
 288 static QemuOptsList raw_runtime_opts = {
 289     .name = "raw",
 290     .head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head),
 291     .desc = {
 292         {
 293             .name = "filename",
 294             .type = QEMU_OPT_STRING,
 295             .help = "File name of the image",
 296         },
 297         {
 298             .name = "aio",
 299             .type = QEMU_OPT_STRING,
 300             .help = "host AIO implementation (threads, native)",
 301         },
 302         { /* end of list */ }
 303     },
 304 };
 305
 306 static bool get_aio_option(QemuOpts *opts, int flags, Error **errp)
 307 {
 308     BlockdevAioOptions aio, aio_default;
 309
 310     aio_default = (flags & BDRV_O_NATIVE_AIO) ? BLOCKDEV_AIO_OPTIONS_NATIVE
 311                                               : BLOCKDEV_AIO_OPTIONS_THREADS;
 312     aio = qapi_enum_parse(&BlockdevAioOptions_lookup, qemu_opt_get(opts, "aio"),
 313                           aio_default, errp);
 314
 315     switch (aio) {
 316     case BLOCKDEV_AIO_OPTIONS_NATIVE:
 317         return true;
 318     case BLOCKDEV_AIO_OPTIONS_THREADS:
 319         return false;
 320     default:
 321         error_setg(errp, "Invalid AIO option");
 322     }
 323     return false;
 324 }
 325
 326 static int raw_open(BlockDriverState *bs, QDict *options, int flags,
 327                     Error **errp)
 328 {
 329     BDRVRawState *s = bs->opaque;
 330     int access_flags;
 331     DWORD overlapped;
 332     QemuOpts *opts;
 333     Error *local_err = NULL;
 334     const char *filename;
 335     bool use_aio;
 336     int ret;
 337
 338     s->type = FTYPE_FILE;
 339
 340     opts = qemu_opts_create(&raw_runtime_opts, NULL, 0, &error_abort);
 341     if (!qemu_opts_absorb_qdict(opts, options, &local_err)) {
 342         error_propagate(errp, local_err);
 343         ret = -EINVAL;
 344         goto fail;
 345     }
 346
 347     if (qdict_get_try_bool(options, "locking", false)) {
 348         error_setg(errp, "locking=on is not supported on Windows");
 349         ret = -EINVAL;
 350         goto fail;
 351     }
 352
 353     filename = qemu_opt_get(opts, "filename");
 354
 355     use_aio = get_aio_option(opts, flags, &local_err);
 356     if (local_err) {
 357         error_propagate(errp, local_err);
 358         ret = -EINVAL;
 359         goto fail;
 360     }
 361
 362     raw_parse_flags(flags, use_aio, &access_flags, &overlapped);
 363
 364     if (filename[0] && filename[1] == ':') {
 365         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", filename[0]);
 366     } else if (filename[0] == '\\' && filename[1] == '\\') {
 367         s->drive_path[0] = 0;
 368     } else {
 369         /* Relative path.  */
 370         char buf[MAX_PATH];
 371         GetCurrentDirectory(MAX_PATH, buf);
 372         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", buf[0]);
 373     }
 374
 375     s->hfile = CreateFile(filename, access_flags,
 376                           FILE_SHARE_READ, NULL,
 377                           OPEN_EXISTING, overlapped, NULL);
 378     if (s->hfile == INVALID_HANDLE_VALUE) {
 379         int err = GetLastError();
 380
 381         error_setg_win32(errp, err, "Could not open '%s'", filename);
 382         if (err == ERROR_ACCESS_DENIED) {
 383             ret = -EACCES;
 384         } else {
 385             ret = -EINVAL;
 386         }
 387         goto fail;
 388     }
 389
 390     if (use_aio) {
 391         s->aio = win32_aio_init();
 392         if (s->aio == NULL) {
 393             CloseHandle(s->hfile);
 394             error_setg(errp, "Could not initialize AIO");
 395             ret = -EINVAL;
 396             goto fail;
 397         }
 398
 399         ret = win32_aio_attach(s->aio, s->hfile);
 400         if (ret < 0) {
 401             win32_aio_cleanup(s->aio);
 402             CloseHandle(s->hfile);
 403             error_setg_errno(errp, -ret, "Could not enable AIO");
 404             goto fail;
 405         }
 406
 407         win32_aio_attach_aio_context(s->aio, bdrv_get_aio_context(bs));
 408     }
 409
 410     /* When extending regular files, we get zeros from the OS */
 411     bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE;
 412
 413     ret = 0;
 414 fail:
 415     qemu_opts_del(opts);
 416     return ret;
 417 }
 418
 419 static BlockAIOCB *raw_aio_preadv(BlockDriverState *bs,
 420                                   uint64_t offset, uint64_t bytes,
 421                                   QEMUIOVector *qiov, int flags,
 422                                   BlockCompletionFunc *cb, void *opaque)
 423 {
 424     BDRVRawState *s = bs->opaque;
 425     if (s->aio) {
 426         return win32_aio_submit(bs, s->aio, s->hfile, offset, bytes, qiov,
 427                                 cb, opaque, QEMU_AIO_READ);
 428     } else {
 429         return paio_submit(bs, s->hfile, offset, qiov, bytes,
 430                            cb, opaque, QEMU_AIO_READ);
 431     }
 432 }
 433
 434 static BlockAIOCB *raw_aio_pwritev(BlockDriverState *bs,
 435                                    uint64_t offset, uint64_t bytes,
 436                                    QEMUIOVector *qiov, int flags,
 437                                    BlockCompletionFunc *cb, void *opaque)
 438 {
 439     BDRVRawState *s = bs->opaque;
 440     if (s->aio) {
 441         return win32_aio_submit(bs, s->aio, s->hfile, offset, bytes, qiov,
 442                                 cb, opaque, QEMU_AIO_WRITE);
 443     } else {
 444         return paio_submit(bs, s->hfile, offset, qiov, bytes,
 445                            cb, opaque, QEMU_AIO_WRITE);
 446     }
 447 }
 448
 449 static BlockAIOCB *raw_aio_flush(BlockDriverState *bs,
 450                          BlockCompletionFunc *cb, void *opaque)
 451 {
 452     BDRVRawState *s = bs->opaque;
 453     return paio_submit(bs, s->hfile, 0, NULL, 0, cb, opaque, QEMU_AIO_FLUSH);
 454 }
 455
 456 static void raw_close(BlockDriverState *bs)
 457 {
 458     BDRVRawState *s = bs->opaque;
 459
 460     if (s->aio) {
 461         win32_aio_detach_aio_context(s->aio, bdrv_get_aio_context(bs));
 462         win32_aio_cleanup(s->aio);
 463         s->aio = NULL;
 464     }
 465
 466     CloseHandle(s->hfile);
 467     if (bs->open_flags & BDRV_O_TEMPORARY) {
 468         unlink(bs->filename);
 469     }
 470 }
 471
 472 static int coroutine_fn raw_co_truncate(BlockDriverState *bs, int64_t offset,
 473                                         bool exact, PreallocMode prealloc,
 474                                         BdrvRequestFlags flags, Error **errp)
 475 {
 476     BDRVRawState *s = bs->opaque;
 477     LONG low, high;
 478     DWORD dwPtrLow;
 479
 480     if (prealloc != PREALLOC_MODE_OFF) {
 481         error_setg(errp, "Unsupported preallocation mode '%s'",
 482                    PreallocMode_str(prealloc));
 483         return -ENOTSUP;
 484     }
 485
 486     low = offset;
 487     high = offset >> 32;
 488
 489     /*
 490      * An error has occurred if the return value is INVALID_SET_FILE_POINTER
 491      * and GetLastError doesn't return NO_ERROR.
 492      */
 493     dwPtrLow = SetFilePointer(s->hfile, low, &high, FILE_BEGIN);
 494     if (dwPtrLow == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
 495         error_setg_win32(errp, GetLastError(), "SetFilePointer error");
 496         return -EIO;
 497     }
 498     if (SetEndOfFile(s->hfile) == 0) {
 499         error_setg_win32(errp, GetLastError(), "SetEndOfFile error");
 500         return -EIO;
 501     }
 502     return 0;
 503 }
 504
 505 static int64_t raw_getlength(BlockDriverState *bs)
 506 {
 507     BDRVRawState *s = bs->opaque;
 508     LARGE_INTEGER l;
 509     ULARGE_INTEGER available, total, total_free;
 510     DISK_GEOMETRY_EX dg;
 511     DWORD count;
 512     BOOL status;
 513
 514     switch(s->type) {
 515     case FTYPE_FILE:
 516         l.LowPart = GetFileSize(s->hfile, (PDWORD)&l.HighPart);
 517         if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
 518             return -EIO;
 519         break;
 520     case FTYPE_CD:
 521         if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
 522             return -EIO;
 523         l.QuadPart = total.QuadPart;
 524         break;
 525     case FTYPE_HARDDISK:
 526         status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
 527                                  NULL, 0, &dg, sizeof(dg), &count, NULL);
 528         if (status != 0) {
 529             l = dg.DiskSize;
 530         }
 531         break;
 532     default:
 533         return -EIO;
 534     }
 535     return l.QuadPart;
 536 }
 537
 538 static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
 539 {
 540     typedef DWORD (WINAPI * get_compressed_t)(const char *filename,
 541                                               DWORD * high);
 542     get_compressed_t get_compressed;
 543     struct _stati64 st;
 544     const char *filename = bs->filename;
 545     /* WinNT support GetCompressedFileSize to determine allocate size */
 546     get_compressed =
 547         (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"),
 548                                             "GetCompressedFileSizeA");
 549     if (get_compressed) {
 550         DWORD high, low;
 551         low = get_compressed(filename, &high);
 552         if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR) {
 553             return (((int64_t) high) << 32) + low;
 554         }
 555     }
 556
 557     if (_stati64(filename, &st) < 0) {
 558         return -1;
 559     }
 560     return st.st_size;
 561 }
 562
 563 static int raw_co_create(BlockdevCreateOptions *options, Error **errp)
 564 {
 565     BlockdevCreateOptionsFile *file_opts;
 566     int fd;
 567
 568     assert(options->driver == BLOCKDEV_DRIVER_FILE);
 569     file_opts = &options->u.file;
 570
 571     if (file_opts->has_preallocation) {
 572         error_setg(errp, "Preallocation is not supported on Windows");
 573         return -EINVAL;
 574     }
 575     if (file_opts->has_nocow) {
 576         error_setg(errp, "nocow is not supported on Windows");
 577         return -EINVAL;
 578     }
 579
 580     fd = qemu_open(file_opts->filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
 581                    0644);
 582     if (fd < 0) {
 583         error_setg_errno(errp, errno, "Could not create file");
 584         return -EIO;
 585     }
 586     set_sparse(fd);
 587     ftruncate(fd, file_opts->size);
 588     qemu_close(fd);
 589
 590     return 0;
 591 }
 592
 593 static int coroutine_fn raw_co_create_opts(BlockDriver *drv,
 594                                            const char *filename,
 595                                            QemuOpts *opts,
 596                                            Error **errp)
 597 {
 598     BlockdevCreateOptions options;
 599     int64_t total_size = 0;
 600
 601     strstart(filename, "file:", &filename);
 602
 603     /* Read out options */
 604     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
 605                           BDRV_SECTOR_SIZE);
 606
 607     options = (BlockdevCreateOptions) {
 608         .driver     = BLOCKDEV_DRIVER_FILE,
 609         .u.file     = {
 610             .filename           = (char *) filename,
 611             .size               = total_size,
 612             .has_preallocation  = false,
 613             .has_nocow          = false,
 614         },
 615     };
 616     return raw_co_create(&options, errp);
 617 }
 618
 619 static QemuOptsList raw_create_opts = {
 620     .name = "raw-create-opts",
 621     .head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head),
 622     .desc = {
 623         {
 624             .name = BLOCK_OPT_SIZE,
 625             .type = QEMU_OPT_SIZE,
 626             .help = "Virtual disk size"
 627         },
 628         { /* end of list */ }
 629     }
 630 };
 631
 632 BlockDriver bdrv_file = {
 633     .format_name        = "file",
 634     .protocol_name      = "file",
 635     .instance_size      = sizeof(BDRVRawState),
 636     .bdrv_needs_filename = true,
 637     .bdrv_parse_filename = raw_parse_filename,
 638     .bdrv_file_open     = raw_open,
 639     .bdrv_refresh_limits = raw_probe_alignment,
 640     .bdrv_close         = raw_close,
 641     .bdrv_co_create_opts = raw_co_create_opts,
 642     .bdrv_has_zero_init = bdrv_has_zero_init_1,
 643
 644     .bdrv_aio_preadv    = raw_aio_preadv,
 645     .bdrv_aio_pwritev   = raw_aio_pwritev,
 646     .bdrv_aio_flush     = raw_aio_flush,
 647
 648     .bdrv_co_truncate   = raw_co_truncate,
 649     .bdrv_getlength     = raw_getlength,
 650     .bdrv_get_allocated_file_size
 651                         = raw_get_allocated_file_size,
 652
 653     .create_opts        = &raw_create_opts,
 654 };
 655
 656 /***********************************************/
 657 /* host device */
 658
 659 static int find_cdrom(char *cdrom_name, int cdrom_name_size)
 660 {
 661     char drives[256], *pdrv = drives;
 662     UINT type;
 663
 664     memset(drives, 0, sizeof(drives));
 665     GetLogicalDriveStrings(sizeof(drives), drives);
 666     while(pdrv[0] != '\0') {
 667         type = GetDriveType(pdrv);
 668         switch(type) {
 669         case DRIVE_CDROM:
 670             snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
 671             return 0;
 672             break;
 673         }
 674         pdrv += lstrlen(pdrv) + 1;
 675     }
 676     return -1;
 677 }
 678
 679 static int find_device_type(BlockDriverState *bs, const char *filename)
 680 {
 681     BDRVRawState *s = bs->opaque;
 682     UINT type;
 683     const char *p;
 684
 685     if (strstart(filename, "\\\\.\\", &p) ||
 686         strstart(filename, "//./", &p)) {
 687         if (stristart(p, "PhysicalDrive", NULL))
 688             return FTYPE_HARDDISK;
 689         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
 690         type = GetDriveType(s->drive_path);
 691         switch (type) {
 692         case DRIVE_REMOVABLE:
 693         case DRIVE_FIXED:
 694             return FTYPE_HARDDISK;
 695         case DRIVE_CDROM:
 696             return FTYPE_CD;
 697         default:
 698             return FTYPE_FILE;
 699         }
 700     } else {
 701         return FTYPE_FILE;
 702     }
 703 }
 704
 705 static int hdev_probe_device(const char *filename)
 706 {
 707     if (strstart(filename, "/dev/cdrom", NULL))
 708         return 100;
 709     if (is_windows_drive(filename))
 710         return 100;
 711     return 0;
 712 }
 713
 714 static void hdev_parse_filename(const char *filename, QDict *options,
 715                                 Error **errp)
 716 {
 717     bdrv_parse_filename_strip_prefix(filename, "host_device:", options);
 718 }
 719
 720 static void hdev_refresh_limits(BlockDriverState *bs, Error **errp)
 721 {
 722     /* XXX Does Windows support AIO on less than 512-byte alignment? */
 723     bs->bl.request_alignment = 512;
 724 }
 725
 726 static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
 727                      Error **errp)
 728 {
 729     BDRVRawState *s = bs->opaque;
 730     int access_flags, create_flags;
 731     int ret = 0;
 732     DWORD overlapped;
 733     char device_name[64];
 734
 735     Error *local_err = NULL;
 736     const char *filename;
 737     bool use_aio;
 738
 739     QemuOpts *opts = qemu_opts_create(&raw_runtime_opts, NULL, 0,
 740                                       &error_abort);
 741     if (!qemu_opts_absorb_qdict(opts, options, &local_err)) {
 742         error_propagate(errp, local_err);
 743         ret = -EINVAL;
 744         goto done;
 745     }
 746
 747     filename = qemu_opt_get(opts, "filename");
 748
 749     use_aio = get_aio_option(opts, flags, &local_err);
 750     if (!local_err && use_aio) {
 751         error_setg(&local_err, "AIO is not supported on Windows host devices");
 752     }
 753     if (local_err) {
 754         error_propagate(errp, local_err);
 755         ret = -EINVAL;
 756         goto done;
 757     }
 758
 759     if (strstart(filename, "/dev/cdrom", NULL)) {
 760         if (find_cdrom(device_name, sizeof(device_name)) < 0) {
 761             error_setg(errp, "Could not open CD-ROM drive");
 762             ret = -ENOENT;
 763             goto done;
 764         }
 765         filename = device_name;
 766     } else {
 767         /* transform drive letters into device name */
 768         if (((filename[0] >= 'a' && filename[0] <= 'z') ||
 769              (filename[0] >= 'A' && filename[0] <= 'Z')) &&
 770             filename[1] == ':' && filename[2] == '\0') {
 771             snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
 772             filename = device_name;
 773         }
 774     }
 775     s->type = find_device_type(bs, filename);
 776
 777     raw_parse_flags(flags, use_aio, &access_flags, &overlapped);
 778
 779     create_flags = OPEN_EXISTING;
 780
 781     s->hfile = CreateFile(filename, access_flags,
 782                           FILE_SHARE_READ, NULL,
 783                           create_flags, overlapped, NULL);
 784     if (s->hfile == INVALID_HANDLE_VALUE) {
 785         int err = GetLastError();
 786
 787         if (err == ERROR_ACCESS_DENIED) {
 788             ret = -EACCES;
 789         } else {
 790             ret = -EINVAL;
 791         }
 792         error_setg_errno(errp, -ret, "Could not open device");
 793         goto done;
 794     }
 795
 796 done:
 797     qemu_opts_del(opts);
 798     return ret;
 799 }
 800
 801 static BlockDriver bdrv_host_device = {
 802     .format_name        = "host_device",
 803     .protocol_name      = "host_device",
 804     .instance_size      = sizeof(BDRVRawState),
 805     .bdrv_needs_filename = true,
 806     .bdrv_parse_filename = hdev_parse_filename,
 807     .bdrv_probe_device  = hdev_probe_device,
 808     .bdrv_file_open     = hdev_open,
 809     .bdrv_close         = raw_close,
 810     .bdrv_refresh_limits = hdev_refresh_limits,
 811
 812     .bdrv_aio_preadv    = raw_aio_preadv,
 813     .bdrv_aio_pwritev   = raw_aio_pwritev,
 814     .bdrv_aio_flush     = raw_aio_flush,
 815
 816     .bdrv_detach_aio_context = raw_detach_aio_context,
 817     .bdrv_attach_aio_context = raw_attach_aio_context,
 818
 819     .bdrv_getlength      = raw_getlength,
 820     .has_variable_length = true,
 821
 822     .bdrv_get_allocated_file_size
 823                         = raw_get_allocated_file_size,
 824 };
 825
 826 static void bdrv_file_init(void)
 827 {
 828     bdrv_register(&bdrv_file);
 829     bdrv_register(&bdrv_host_device);
 830 }
 831
 832 block_init(bdrv_file_init);