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