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