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