xref: /openbmc/qemu/block/file-win32.c (revision 0806b30c8dff64e944456aa15bdc6957384e29a8)
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 "qapi/util.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, bool use_aio, int *access_flags,
256                             DWORD *overlapped)
257 {
258     assert(access_flags != NULL);
259     assert(overlapped != NULL);
260 
261     if (flags & BDRV_O_RDWR) {
262         *access_flags = GENERIC_READ | GENERIC_WRITE;
263     } else {
264         *access_flags = GENERIC_READ;
265     }
266 
267     *overlapped = FILE_ATTRIBUTE_NORMAL;
268     if (use_aio) {
269         *overlapped |= FILE_FLAG_OVERLAPPED;
270     }
271     if (flags & BDRV_O_NOCACHE) {
272         *overlapped |= FILE_FLAG_NO_BUFFERING;
273     }
274 }
275 
276 static void raw_parse_filename(const char *filename, QDict *options,
277                                Error **errp)
278 {
279     /* The filename does not have to be prefixed by the protocol name, since
280      * "file" is the default protocol; therefore, the return value of this
281      * function call can be ignored. */
282     strstart(filename, "file:", &filename);
283 
284     qdict_put_str(options, "filename", filename);
285 }
286 
287 static QemuOptsList raw_runtime_opts = {
288     .name = "raw",
289     .head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head),
290     .desc = {
291         {
292             .name = "filename",
293             .type = QEMU_OPT_STRING,
294             .help = "File name of the image",
295         },
296         {
297             .name = "aio",
298             .type = QEMU_OPT_STRING,
299             .help = "host AIO implementation (threads, native)",
300         },
301         { /* end of list */ }
302     },
303 };
304 
305 static bool get_aio_option(QemuOpts *opts, int flags, Error **errp)
306 {
307     BlockdevAioOptions aio, aio_default;
308 
309     aio_default = (flags & BDRV_O_NATIVE_AIO) ? BLOCKDEV_AIO_OPTIONS_NATIVE
310                                               : BLOCKDEV_AIO_OPTIONS_THREADS;
311     aio = qapi_enum_parse(BlockdevAioOptions_lookup, qemu_opt_get(opts, "aio"),
312                           BLOCKDEV_AIO_OPTIONS__MAX, aio_default, errp);
313 
314     switch (aio) {
315     case BLOCKDEV_AIO_OPTIONS_NATIVE:
316         return true;
317     case BLOCKDEV_AIO_OPTIONS_THREADS:
318         return false;
319     default:
320         error_setg(errp, "Invalid AIO option");
321     }
322     return false;
323 }
324 
325 static int raw_open(BlockDriverState *bs, QDict *options, int flags,
326                     Error **errp)
327 {
328     BDRVRawState *s = bs->opaque;
329     int access_flags;
330     DWORD overlapped;
331     QemuOpts *opts;
332     Error *local_err = NULL;
333     const char *filename;
334     bool use_aio;
335     int ret;
336 
337     s->type = FTYPE_FILE;
338 
339     opts = qemu_opts_create(&raw_runtime_opts, NULL, 0, &error_abort);
340     qemu_opts_absorb_qdict(opts, options, &local_err);
341     if (local_err) {
342         error_propagate(errp, local_err);
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, Error **errp)
464 {
465     BDRVRawState *s = bs->opaque;
466     LONG low, high;
467     DWORD dwPtrLow;
468 
469     low = offset;
470     high = offset >> 32;
471 
472     /*
473      * An error has occurred if the return value is INVALID_SET_FILE_POINTER
474      * and GetLastError doesn't return NO_ERROR.
475      */
476     dwPtrLow = SetFilePointer(s->hfile, low, &high, FILE_BEGIN);
477     if (dwPtrLow == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
478         error_setg_win32(errp, GetLastError(), "SetFilePointer error");
479         return -EIO;
480     }
481     if (SetEndOfFile(s->hfile) == 0) {
482         error_setg_win32(errp, GetLastError(), "SetEndOfFile error");
483         return -EIO;
484     }
485     return 0;
486 }
487 
488 static int64_t raw_getlength(BlockDriverState *bs)
489 {
490     BDRVRawState *s = bs->opaque;
491     LARGE_INTEGER l;
492     ULARGE_INTEGER available, total, total_free;
493     DISK_GEOMETRY_EX dg;
494     DWORD count;
495     BOOL status;
496 
497     switch(s->type) {
498     case FTYPE_FILE:
499         l.LowPart = GetFileSize(s->hfile, (PDWORD)&l.HighPart);
500         if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
501             return -EIO;
502         break;
503     case FTYPE_CD:
504         if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
505             return -EIO;
506         l.QuadPart = total.QuadPart;
507         break;
508     case FTYPE_HARDDISK:
509         status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
510                                  NULL, 0, &dg, sizeof(dg), &count, NULL);
511         if (status != 0) {
512             l = dg.DiskSize;
513         }
514         break;
515     default:
516         return -EIO;
517     }
518     return l.QuadPart;
519 }
520 
521 static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
522 {
523     typedef DWORD (WINAPI * get_compressed_t)(const char *filename,
524                                               DWORD * high);
525     get_compressed_t get_compressed;
526     struct _stati64 st;
527     const char *filename = bs->filename;
528     /* WinNT support GetCompressedFileSize to determine allocate size */
529     get_compressed =
530         (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"),
531                                             "GetCompressedFileSizeA");
532     if (get_compressed) {
533         DWORD high, low;
534         low = get_compressed(filename, &high);
535         if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR) {
536             return (((int64_t) high) << 32) + low;
537         }
538     }
539 
540     if (_stati64(filename, &st) < 0) {
541         return -1;
542     }
543     return st.st_size;
544 }
545 
546 static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
547 {
548     int fd;
549     int64_t total_size = 0;
550 
551     strstart(filename, "file:", &filename);
552 
553     /* Read out options */
554     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
555                           BDRV_SECTOR_SIZE);
556 
557     fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
558                    0644);
559     if (fd < 0) {
560         error_setg_errno(errp, errno, "Could not create file");
561         return -EIO;
562     }
563     set_sparse(fd);
564     ftruncate(fd, total_size);
565     qemu_close(fd);
566     return 0;
567 }
568 
569 
570 static QemuOptsList raw_create_opts = {
571     .name = "raw-create-opts",
572     .head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head),
573     .desc = {
574         {
575             .name = BLOCK_OPT_SIZE,
576             .type = QEMU_OPT_SIZE,
577             .help = "Virtual disk size"
578         },
579         { /* end of list */ }
580     }
581 };
582 
583 BlockDriver bdrv_file = {
584     .format_name	= "file",
585     .protocol_name	= "file",
586     .instance_size	= sizeof(BDRVRawState),
587     .bdrv_needs_filename = true,
588     .bdrv_parse_filename = raw_parse_filename,
589     .bdrv_file_open     = raw_open,
590     .bdrv_refresh_limits = raw_probe_alignment,
591     .bdrv_close         = raw_close,
592     .bdrv_create        = raw_create,
593     .bdrv_has_zero_init = bdrv_has_zero_init_1,
594 
595     .bdrv_aio_readv     = raw_aio_readv,
596     .bdrv_aio_writev    = raw_aio_writev,
597     .bdrv_aio_flush     = raw_aio_flush,
598 
599     .bdrv_truncate	= raw_truncate,
600     .bdrv_getlength	= raw_getlength,
601     .bdrv_get_allocated_file_size
602                         = raw_get_allocated_file_size,
603 
604     .create_opts        = &raw_create_opts,
605 };
606 
607 /***********************************************/
608 /* host device */
609 
610 static int find_cdrom(char *cdrom_name, int cdrom_name_size)
611 {
612     char drives[256], *pdrv = drives;
613     UINT type;
614 
615     memset(drives, 0, sizeof(drives));
616     GetLogicalDriveStrings(sizeof(drives), drives);
617     while(pdrv[0] != '\0') {
618         type = GetDriveType(pdrv);
619         switch(type) {
620         case DRIVE_CDROM:
621             snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
622             return 0;
623             break;
624         }
625         pdrv += lstrlen(pdrv) + 1;
626     }
627     return -1;
628 }
629 
630 static int find_device_type(BlockDriverState *bs, const char *filename)
631 {
632     BDRVRawState *s = bs->opaque;
633     UINT type;
634     const char *p;
635 
636     if (strstart(filename, "\\\\.\\", &p) ||
637         strstart(filename, "//./", &p)) {
638         if (stristart(p, "PhysicalDrive", NULL))
639             return FTYPE_HARDDISK;
640         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
641         type = GetDriveType(s->drive_path);
642         switch (type) {
643         case DRIVE_REMOVABLE:
644         case DRIVE_FIXED:
645             return FTYPE_HARDDISK;
646         case DRIVE_CDROM:
647             return FTYPE_CD;
648         default:
649             return FTYPE_FILE;
650         }
651     } else {
652         return FTYPE_FILE;
653     }
654 }
655 
656 static int hdev_probe_device(const char *filename)
657 {
658     if (strstart(filename, "/dev/cdrom", NULL))
659         return 100;
660     if (is_windows_drive(filename))
661         return 100;
662     return 0;
663 }
664 
665 static void hdev_parse_filename(const char *filename, QDict *options,
666                                 Error **errp)
667 {
668     /* The prefix is optional, just as for "file". */
669     strstart(filename, "host_device:", &filename);
670 
671     qdict_put_str(options, "filename", filename);
672 }
673 
674 static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
675                      Error **errp)
676 {
677     BDRVRawState *s = bs->opaque;
678     int access_flags, create_flags;
679     int ret = 0;
680     DWORD overlapped;
681     char device_name[64];
682 
683     Error *local_err = NULL;
684     const char *filename;
685     bool use_aio;
686 
687     QemuOpts *opts = qemu_opts_create(&raw_runtime_opts, NULL, 0,
688                                       &error_abort);
689     qemu_opts_absorb_qdict(opts, options, &local_err);
690     if (local_err) {
691         error_propagate(errp, local_err);
692         ret = -EINVAL;
693         goto done;
694     }
695 
696     filename = qemu_opt_get(opts, "filename");
697 
698     use_aio = get_aio_option(opts, flags, &local_err);
699     if (!local_err && use_aio) {
700         error_setg(&local_err, "AIO is not supported on Windows host devices");
701     }
702     if (local_err) {
703         error_propagate(errp, local_err);
704         ret = -EINVAL;
705         goto done;
706     }
707 
708     if (strstart(filename, "/dev/cdrom", NULL)) {
709         if (find_cdrom(device_name, sizeof(device_name)) < 0) {
710             error_setg(errp, "Could not open CD-ROM drive");
711             ret = -ENOENT;
712             goto done;
713         }
714         filename = device_name;
715     } else {
716         /* transform drive letters into device name */
717         if (((filename[0] >= 'a' && filename[0] <= 'z') ||
718              (filename[0] >= 'A' && filename[0] <= 'Z')) &&
719             filename[1] == ':' && filename[2] == '\0') {
720             snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
721             filename = device_name;
722         }
723     }
724     s->type = find_device_type(bs, filename);
725 
726     raw_parse_flags(flags, use_aio, &access_flags, &overlapped);
727 
728     create_flags = OPEN_EXISTING;
729 
730     s->hfile = CreateFile(filename, access_flags,
731                           FILE_SHARE_READ, NULL,
732                           create_flags, overlapped, NULL);
733     if (s->hfile == INVALID_HANDLE_VALUE) {
734         int err = GetLastError();
735 
736         if (err == ERROR_ACCESS_DENIED) {
737             ret = -EACCES;
738         } else {
739             ret = -EINVAL;
740         }
741         error_setg_errno(errp, -ret, "Could not open device");
742         goto done;
743     }
744 
745 done:
746     qemu_opts_del(opts);
747     return ret;
748 }
749 
750 static BlockDriver bdrv_host_device = {
751     .format_name	= "host_device",
752     .protocol_name	= "host_device",
753     .instance_size	= sizeof(BDRVRawState),
754     .bdrv_needs_filename = true,
755     .bdrv_parse_filename = hdev_parse_filename,
756     .bdrv_probe_device	= hdev_probe_device,
757     .bdrv_file_open	= hdev_open,
758     .bdrv_close		= raw_close,
759 
760     .bdrv_aio_readv     = raw_aio_readv,
761     .bdrv_aio_writev    = raw_aio_writev,
762     .bdrv_aio_flush     = raw_aio_flush,
763 
764     .bdrv_detach_aio_context = raw_detach_aio_context,
765     .bdrv_attach_aio_context = raw_attach_aio_context,
766 
767     .bdrv_getlength      = raw_getlength,
768     .has_variable_length = true,
769 
770     .bdrv_get_allocated_file_size
771                         = raw_get_allocated_file_size,
772 };
773 
774 static void bdrv_file_init(void)
775 {
776     bdrv_register(&bdrv_file);
777     bdrv_register(&bdrv_host_device);
778 }
779 
780 block_init(bdrv_file_init);
781