xref: /openbmc/qemu/block/file-win32.c (revision 795c40b8)
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     if (qdict_get_try_bool(options, "locking", false)) {
348         error_setg(errp, "locking=on is not supported on Windows");
349         ret = -EINVAL;
350         goto fail;
351     }
352 
353     filename = qemu_opt_get(opts, "filename");
354 
355     use_aio = get_aio_option(opts, flags, &local_err);
356     if (local_err) {
357         error_propagate(errp, local_err);
358         ret = -EINVAL;
359         goto fail;
360     }
361 
362     raw_parse_flags(flags, use_aio, &access_flags, &overlapped);
363 
364     if (filename[0] && filename[1] == ':') {
365         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", filename[0]);
366     } else if (filename[0] == '\\' && filename[1] == '\\') {
367         s->drive_path[0] = 0;
368     } else {
369         /* Relative path.  */
370         char buf[MAX_PATH];
371         GetCurrentDirectory(MAX_PATH, buf);
372         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", buf[0]);
373     }
374 
375     s->hfile = CreateFile(filename, access_flags,
376                           FILE_SHARE_READ, NULL,
377                           OPEN_EXISTING, overlapped, NULL);
378     if (s->hfile == INVALID_HANDLE_VALUE) {
379         int err = GetLastError();
380 
381         error_setg_win32(errp, err, "Could not open '%s'", filename);
382         if (err == ERROR_ACCESS_DENIED) {
383             ret = -EACCES;
384         } else {
385             ret = -EINVAL;
386         }
387         goto fail;
388     }
389 
390     if (use_aio) {
391         s->aio = win32_aio_init();
392         if (s->aio == NULL) {
393             CloseHandle(s->hfile);
394             error_setg(errp, "Could not initialize AIO");
395             ret = -EINVAL;
396             goto fail;
397         }
398 
399         ret = win32_aio_attach(s->aio, s->hfile);
400         if (ret < 0) {
401             win32_aio_cleanup(s->aio);
402             CloseHandle(s->hfile);
403             error_setg_errno(errp, -ret, "Could not enable AIO");
404             goto fail;
405         }
406 
407         win32_aio_attach_aio_context(s->aio, bdrv_get_aio_context(bs));
408     }
409 
410     ret = 0;
411 fail:
412     qemu_opts_del(opts);
413     return ret;
414 }
415 
416 static BlockAIOCB *raw_aio_readv(BlockDriverState *bs,
417                          int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
418                          BlockCompletionFunc *cb, void *opaque)
419 {
420     BDRVRawState *s = bs->opaque;
421     if (s->aio) {
422         return win32_aio_submit(bs, s->aio, s->hfile, sector_num, qiov,
423                                 nb_sectors, cb, opaque, QEMU_AIO_READ);
424     } else {
425         return paio_submit(bs, s->hfile, sector_num << BDRV_SECTOR_BITS, qiov,
426                            nb_sectors << BDRV_SECTOR_BITS,
427                            cb, opaque, QEMU_AIO_READ);
428     }
429 }
430 
431 static BlockAIOCB *raw_aio_writev(BlockDriverState *bs,
432                           int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
433                           BlockCompletionFunc *cb, void *opaque)
434 {
435     BDRVRawState *s = bs->opaque;
436     if (s->aio) {
437         return win32_aio_submit(bs, s->aio, s->hfile, sector_num, qiov,
438                                 nb_sectors, cb, opaque, QEMU_AIO_WRITE);
439     } else {
440         return paio_submit(bs, s->hfile, sector_num << BDRV_SECTOR_BITS, qiov,
441                            nb_sectors << BDRV_SECTOR_BITS,
442                            cb, opaque, QEMU_AIO_WRITE);
443     }
444 }
445 
446 static BlockAIOCB *raw_aio_flush(BlockDriverState *bs,
447                          BlockCompletionFunc *cb, void *opaque)
448 {
449     BDRVRawState *s = bs->opaque;
450     return paio_submit(bs, s->hfile, 0, NULL, 0, cb, opaque, QEMU_AIO_FLUSH);
451 }
452 
453 static void raw_close(BlockDriverState *bs)
454 {
455     BDRVRawState *s = bs->opaque;
456 
457     if (s->aio) {
458         win32_aio_detach_aio_context(s->aio, bdrv_get_aio_context(bs));
459         win32_aio_cleanup(s->aio);
460         s->aio = NULL;
461     }
462 
463     CloseHandle(s->hfile);
464     if (bs->open_flags & BDRV_O_TEMPORARY) {
465         unlink(bs->filename);
466     }
467 }
468 
469 static int raw_truncate(BlockDriverState *bs, int64_t offset, Error **errp)
470 {
471     BDRVRawState *s = bs->opaque;
472     LONG low, high;
473     DWORD dwPtrLow;
474 
475     low = offset;
476     high = offset >> 32;
477 
478     /*
479      * An error has occurred if the return value is INVALID_SET_FILE_POINTER
480      * and GetLastError doesn't return NO_ERROR.
481      */
482     dwPtrLow = SetFilePointer(s->hfile, low, &high, FILE_BEGIN);
483     if (dwPtrLow == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
484         error_setg_win32(errp, GetLastError(), "SetFilePointer error");
485         return -EIO;
486     }
487     if (SetEndOfFile(s->hfile) == 0) {
488         error_setg_win32(errp, GetLastError(), "SetEndOfFile error");
489         return -EIO;
490     }
491     return 0;
492 }
493 
494 static int64_t raw_getlength(BlockDriverState *bs)
495 {
496     BDRVRawState *s = bs->opaque;
497     LARGE_INTEGER l;
498     ULARGE_INTEGER available, total, total_free;
499     DISK_GEOMETRY_EX dg;
500     DWORD count;
501     BOOL status;
502 
503     switch(s->type) {
504     case FTYPE_FILE:
505         l.LowPart = GetFileSize(s->hfile, (PDWORD)&l.HighPart);
506         if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
507             return -EIO;
508         break;
509     case FTYPE_CD:
510         if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
511             return -EIO;
512         l.QuadPart = total.QuadPart;
513         break;
514     case FTYPE_HARDDISK:
515         status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
516                                  NULL, 0, &dg, sizeof(dg), &count, NULL);
517         if (status != 0) {
518             l = dg.DiskSize;
519         }
520         break;
521     default:
522         return -EIO;
523     }
524     return l.QuadPart;
525 }
526 
527 static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
528 {
529     typedef DWORD (WINAPI * get_compressed_t)(const char *filename,
530                                               DWORD * high);
531     get_compressed_t get_compressed;
532     struct _stati64 st;
533     const char *filename = bs->filename;
534     /* WinNT support GetCompressedFileSize to determine allocate size */
535     get_compressed =
536         (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"),
537                                             "GetCompressedFileSizeA");
538     if (get_compressed) {
539         DWORD high, low;
540         low = get_compressed(filename, &high);
541         if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR) {
542             return (((int64_t) high) << 32) + low;
543         }
544     }
545 
546     if (_stati64(filename, &st) < 0) {
547         return -1;
548     }
549     return st.st_size;
550 }
551 
552 static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
553 {
554     int fd;
555     int64_t total_size = 0;
556 
557     strstart(filename, "file:", &filename);
558 
559     /* Read out options */
560     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
561                           BDRV_SECTOR_SIZE);
562 
563     fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
564                    0644);
565     if (fd < 0) {
566         error_setg_errno(errp, errno, "Could not create file");
567         return -EIO;
568     }
569     set_sparse(fd);
570     ftruncate(fd, total_size);
571     qemu_close(fd);
572     return 0;
573 }
574 
575 
576 static QemuOptsList raw_create_opts = {
577     .name = "raw-create-opts",
578     .head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head),
579     .desc = {
580         {
581             .name = BLOCK_OPT_SIZE,
582             .type = QEMU_OPT_SIZE,
583             .help = "Virtual disk size"
584         },
585         { /* end of list */ }
586     }
587 };
588 
589 BlockDriver bdrv_file = {
590     .format_name	= "file",
591     .protocol_name	= "file",
592     .instance_size	= sizeof(BDRVRawState),
593     .bdrv_needs_filename = true,
594     .bdrv_parse_filename = raw_parse_filename,
595     .bdrv_file_open     = raw_open,
596     .bdrv_refresh_limits = raw_probe_alignment,
597     .bdrv_close         = raw_close,
598     .bdrv_create        = raw_create,
599     .bdrv_has_zero_init = bdrv_has_zero_init_1,
600 
601     .bdrv_aio_readv     = raw_aio_readv,
602     .bdrv_aio_writev    = raw_aio_writev,
603     .bdrv_aio_flush     = raw_aio_flush,
604 
605     .bdrv_truncate	= raw_truncate,
606     .bdrv_getlength	= raw_getlength,
607     .bdrv_get_allocated_file_size
608                         = raw_get_allocated_file_size,
609 
610     .create_opts        = &raw_create_opts,
611 };
612 
613 /***********************************************/
614 /* host device */
615 
616 static int find_cdrom(char *cdrom_name, int cdrom_name_size)
617 {
618     char drives[256], *pdrv = drives;
619     UINT type;
620 
621     memset(drives, 0, sizeof(drives));
622     GetLogicalDriveStrings(sizeof(drives), drives);
623     while(pdrv[0] != '\0') {
624         type = GetDriveType(pdrv);
625         switch(type) {
626         case DRIVE_CDROM:
627             snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
628             return 0;
629             break;
630         }
631         pdrv += lstrlen(pdrv) + 1;
632     }
633     return -1;
634 }
635 
636 static int find_device_type(BlockDriverState *bs, const char *filename)
637 {
638     BDRVRawState *s = bs->opaque;
639     UINT type;
640     const char *p;
641 
642     if (strstart(filename, "\\\\.\\", &p) ||
643         strstart(filename, "//./", &p)) {
644         if (stristart(p, "PhysicalDrive", NULL))
645             return FTYPE_HARDDISK;
646         snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
647         type = GetDriveType(s->drive_path);
648         switch (type) {
649         case DRIVE_REMOVABLE:
650         case DRIVE_FIXED:
651             return FTYPE_HARDDISK;
652         case DRIVE_CDROM:
653             return FTYPE_CD;
654         default:
655             return FTYPE_FILE;
656         }
657     } else {
658         return FTYPE_FILE;
659     }
660 }
661 
662 static int hdev_probe_device(const char *filename)
663 {
664     if (strstart(filename, "/dev/cdrom", NULL))
665         return 100;
666     if (is_windows_drive(filename))
667         return 100;
668     return 0;
669 }
670 
671 static void hdev_parse_filename(const char *filename, QDict *options,
672                                 Error **errp)
673 {
674     /* The prefix is optional, just as for "file". */
675     strstart(filename, "host_device:", &filename);
676 
677     qdict_put_str(options, "filename", filename);
678 }
679 
680 static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
681                      Error **errp)
682 {
683     BDRVRawState *s = bs->opaque;
684     int access_flags, create_flags;
685     int ret = 0;
686     DWORD overlapped;
687     char device_name[64];
688 
689     Error *local_err = NULL;
690     const char *filename;
691     bool use_aio;
692 
693     QemuOpts *opts = qemu_opts_create(&raw_runtime_opts, NULL, 0,
694                                       &error_abort);
695     qemu_opts_absorb_qdict(opts, options, &local_err);
696     if (local_err) {
697         error_propagate(errp, local_err);
698         ret = -EINVAL;
699         goto done;
700     }
701 
702     filename = qemu_opt_get(opts, "filename");
703 
704     use_aio = get_aio_option(opts, flags, &local_err);
705     if (!local_err && use_aio) {
706         error_setg(&local_err, "AIO is not supported on Windows host devices");
707     }
708     if (local_err) {
709         error_propagate(errp, local_err);
710         ret = -EINVAL;
711         goto done;
712     }
713 
714     if (strstart(filename, "/dev/cdrom", NULL)) {
715         if (find_cdrom(device_name, sizeof(device_name)) < 0) {
716             error_setg(errp, "Could not open CD-ROM drive");
717             ret = -ENOENT;
718             goto done;
719         }
720         filename = device_name;
721     } else {
722         /* transform drive letters into device name */
723         if (((filename[0] >= 'a' && filename[0] <= 'z') ||
724              (filename[0] >= 'A' && filename[0] <= 'Z')) &&
725             filename[1] == ':' && filename[2] == '\0') {
726             snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
727             filename = device_name;
728         }
729     }
730     s->type = find_device_type(bs, filename);
731 
732     raw_parse_flags(flags, use_aio, &access_flags, &overlapped);
733 
734     create_flags = OPEN_EXISTING;
735 
736     s->hfile = CreateFile(filename, access_flags,
737                           FILE_SHARE_READ, NULL,
738                           create_flags, overlapped, NULL);
739     if (s->hfile == INVALID_HANDLE_VALUE) {
740         int err = GetLastError();
741 
742         if (err == ERROR_ACCESS_DENIED) {
743             ret = -EACCES;
744         } else {
745             ret = -EINVAL;
746         }
747         error_setg_errno(errp, -ret, "Could not open device");
748         goto done;
749     }
750 
751 done:
752     qemu_opts_del(opts);
753     return ret;
754 }
755 
756 static BlockDriver bdrv_host_device = {
757     .format_name	= "host_device",
758     .protocol_name	= "host_device",
759     .instance_size	= sizeof(BDRVRawState),
760     .bdrv_needs_filename = true,
761     .bdrv_parse_filename = hdev_parse_filename,
762     .bdrv_probe_device	= hdev_probe_device,
763     .bdrv_file_open	= hdev_open,
764     .bdrv_close		= raw_close,
765 
766     .bdrv_aio_readv     = raw_aio_readv,
767     .bdrv_aio_writev    = raw_aio_writev,
768     .bdrv_aio_flush     = raw_aio_flush,
769 
770     .bdrv_detach_aio_context = raw_detach_aio_context,
771     .bdrv_attach_aio_context = raw_attach_aio_context,
772 
773     .bdrv_getlength      = raw_getlength,
774     .has_variable_length = true,
775 
776     .bdrv_get_allocated_file_size
777                         = raw_get_allocated_file_size,
778 };
779 
780 static void bdrv_file_init(void)
781 {
782     bdrv_register(&bdrv_file);
783     bdrv_register(&bdrv_host_device);
784 }
785 
786 block_init(bdrv_file_init);
787