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1
/*
2
 * QEMU System Emulator block driver
3
 *
4
 * Copyright (c) 2003 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 "config-host.h"
25
#ifdef _BSD
26
/* include native header before sys-queue.h */
27
#include <sys/queue.h>
28
#endif
29

    
30
#include "qemu-common.h"
31
#include "console.h"
32
#include "block_int.h"
33

    
34
#ifdef _BSD
35
#include <sys/types.h>
36
#include <sys/stat.h>
37
#include <sys/ioctl.h>
38
#include <sys/disk.h>
39
#endif
40

    
41
#define SECTOR_BITS 9
42
#define SECTOR_SIZE (1 << SECTOR_BITS)
43

    
44
typedef struct BlockDriverAIOCBSync {
45
    BlockDriverAIOCB common;
46
    QEMUBH *bh;
47
    int ret;
48
} BlockDriverAIOCBSync;
49

    
50
static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
51
        int64_t sector_num, uint8_t *buf, int nb_sectors,
52
        BlockDriverCompletionFunc *cb, void *opaque);
53
static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
54
        int64_t sector_num, const uint8_t *buf, int nb_sectors,
55
        BlockDriverCompletionFunc *cb, void *opaque);
56
static void bdrv_aio_cancel_em(BlockDriverAIOCB *acb);
57
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
58
                        uint8_t *buf, int nb_sectors);
59
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
60
                         const uint8_t *buf, int nb_sectors);
61

    
62
BlockDriverState *bdrv_first;
63

    
64
static BlockDriver *first_drv;
65

    
66
int path_is_absolute(const char *path)
67
{
68
    const char *p;
69
#ifdef _WIN32
70
    /* specific case for names like: "\\.\d:" */
71
    if (*path == '/' || *path == '\\')
72
        return 1;
73
#endif
74
    p = strchr(path, ':');
75
    if (p)
76
        p++;
77
    else
78
        p = path;
79
#ifdef _WIN32
80
    return (*p == '/' || *p == '\\');
81
#else
82
    return (*p == '/');
83
#endif
84
}
85

    
86
/* if filename is absolute, just copy it to dest. Otherwise, build a
87
   path to it by considering it is relative to base_path. URL are
88
   supported. */
89
void path_combine(char *dest, int dest_size,
90
                  const char *base_path,
91
                  const char *filename)
92
{
93
    const char *p, *p1;
94
    int len;
95

    
96
    if (dest_size <= 0)
97
        return;
98
    if (path_is_absolute(filename)) {
99
        pstrcpy(dest, dest_size, filename);
100
    } else {
101
        p = strchr(base_path, ':');
102
        if (p)
103
            p++;
104
        else
105
            p = base_path;
106
        p1 = strrchr(base_path, '/');
107
#ifdef _WIN32
108
        {
109
            const char *p2;
110
            p2 = strrchr(base_path, '\\');
111
            if (!p1 || p2 > p1)
112
                p1 = p2;
113
        }
114
#endif
115
        if (p1)
116
            p1++;
117
        else
118
            p1 = base_path;
119
        if (p1 > p)
120
            p = p1;
121
        len = p - base_path;
122
        if (len > dest_size - 1)
123
            len = dest_size - 1;
124
        memcpy(dest, base_path, len);
125
        dest[len] = '\0';
126
        pstrcat(dest, dest_size, filename);
127
    }
128
}
129

    
130

    
131
static void bdrv_register(BlockDriver *bdrv)
132
{
133
    if (!bdrv->bdrv_aio_read) {
134
        /* add AIO emulation layer */
135
        bdrv->bdrv_aio_read = bdrv_aio_read_em;
136
        bdrv->bdrv_aio_write = bdrv_aio_write_em;
137
        bdrv->bdrv_aio_cancel = bdrv_aio_cancel_em;
138
        bdrv->aiocb_size = sizeof(BlockDriverAIOCBSync);
139
    } else if (!bdrv->bdrv_read && !bdrv->bdrv_pread) {
140
        /* add synchronous IO emulation layer */
141
        bdrv->bdrv_read = bdrv_read_em;
142
        bdrv->bdrv_write = bdrv_write_em;
143
    }
144
    bdrv->next = first_drv;
145
    first_drv = bdrv;
146
}
147

    
148
/* create a new block device (by default it is empty) */
149
BlockDriverState *bdrv_new(const char *device_name)
150
{
151
    BlockDriverState **pbs, *bs;
152

    
153
    bs = qemu_mallocz(sizeof(BlockDriverState));
154
    if(!bs)
155
        return NULL;
156
    pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
157
    if (device_name[0] != '\0') {
158
        /* insert at the end */
159
        pbs = &bdrv_first;
160
        while (*pbs != NULL)
161
            pbs = &(*pbs)->next;
162
        *pbs = bs;
163
    }
164
    return bs;
165
}
166

    
167
BlockDriver *bdrv_find_format(const char *format_name)
168
{
169
    BlockDriver *drv1;
170
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
171
        if (!strcmp(drv1->format_name, format_name))
172
            return drv1;
173
    }
174
    return NULL;
175
}
176

    
177
int bdrv_create(BlockDriver *drv,
178
                const char *filename, int64_t size_in_sectors,
179
                const char *backing_file, int flags)
180
{
181
    if (!drv->bdrv_create)
182
        return -ENOTSUP;
183
    return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
184
}
185

    
186
#ifdef _WIN32
187
void get_tmp_filename(char *filename, int size)
188
{
189
    char temp_dir[MAX_PATH];
190

    
191
    GetTempPath(MAX_PATH, temp_dir);
192
    GetTempFileName(temp_dir, "qem", 0, filename);
193
}
194
#else
195
void get_tmp_filename(char *filename, int size)
196
{
197
    int fd;
198
    const char *tmpdir;
199
    /* XXX: race condition possible */
200
    tmpdir = getenv("TMPDIR");
201
    if (!tmpdir)
202
        tmpdir = "/tmp";
203
    snprintf(filename, size, "%s/vl.XXXXXX", tmpdir);
204
    fd = mkstemp(filename);
205
    close(fd);
206
}
207
#endif
208

    
209
#ifdef _WIN32
210
static int is_windows_drive_prefix(const char *filename)
211
{
212
    return (((filename[0] >= 'a' && filename[0] <= 'z') ||
213
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
214
            filename[1] == ':');
215
}
216

    
217
static int is_windows_drive(const char *filename)
218
{
219
    if (is_windows_drive_prefix(filename) &&
220
        filename[2] == '\0')
221
        return 1;
222
    if (strstart(filename, "\\\\.\\", NULL) ||
223
        strstart(filename, "//./", NULL))
224
        return 1;
225
    return 0;
226
}
227
#endif
228

    
229
static BlockDriver *find_protocol(const char *filename)
230
{
231
    BlockDriver *drv1;
232
    char protocol[128];
233
    int len;
234
    const char *p;
235

    
236
#ifdef _WIN32
237
    if (is_windows_drive(filename) ||
238
        is_windows_drive_prefix(filename))
239
        return &bdrv_raw;
240
#endif
241
    p = strchr(filename, ':');
242
    if (!p)
243
        return &bdrv_raw;
244
    len = p - filename;
245
    if (len > sizeof(protocol) - 1)
246
        len = sizeof(protocol) - 1;
247
    memcpy(protocol, filename, len);
248
    protocol[len] = '\0';
249
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
250
        if (drv1->protocol_name &&
251
            !strcmp(drv1->protocol_name, protocol))
252
            return drv1;
253
    }
254
    return NULL;
255
}
256

    
257
/* XXX: force raw format if block or character device ? It would
258
   simplify the BSD case */
259
static BlockDriver *find_image_format(const char *filename)
260
{
261
    int ret, score, score_max;
262
    BlockDriver *drv1, *drv;
263
    uint8_t buf[2048];
264
    BlockDriverState *bs;
265

    
266
    /* detect host devices. By convention, /dev/cdrom[N] is always
267
       recognized as a host CDROM */
268
    if (strstart(filename, "/dev/cdrom", NULL))
269
        return &bdrv_host_device;
270
#ifdef _WIN32
271
    if (is_windows_drive(filename))
272
        return &bdrv_host_device;
273
#else
274
    {
275
        struct stat st;
276
        if (stat(filename, &st) >= 0 &&
277
            (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
278
            return &bdrv_host_device;
279
        }
280
    }
281
#endif
282

    
283
    drv = find_protocol(filename);
284
    /* no need to test disk image formats for vvfat */
285
    if (drv == &bdrv_vvfat)
286
        return drv;
287

    
288
    ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
289
    if (ret < 0)
290
        return NULL;
291
    ret = bdrv_pread(bs, 0, buf, sizeof(buf));
292
    bdrv_delete(bs);
293
    if (ret < 0) {
294
        return NULL;
295
    }
296

    
297
    score_max = 0;
298
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
299
        if (drv1->bdrv_probe) {
300
            score = drv1->bdrv_probe(buf, ret, filename);
301
            if (score > score_max) {
302
                score_max = score;
303
                drv = drv1;
304
            }
305
        }
306
    }
307
    return drv;
308
}
309

    
310
int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
311
{
312
    BlockDriverState *bs;
313
    int ret;
314

    
315
    bs = bdrv_new("");
316
    if (!bs)
317
        return -ENOMEM;
318
    ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL);
319
    if (ret < 0) {
320
        bdrv_delete(bs);
321
        return ret;
322
    }
323
    *pbs = bs;
324
    return 0;
325
}
326

    
327
int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
328
{
329
    return bdrv_open2(bs, filename, flags, NULL);
330
}
331

    
332
int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
333
               BlockDriver *drv)
334
{
335
    int ret, open_flags;
336
    char tmp_filename[PATH_MAX];
337
    char backing_filename[PATH_MAX];
338

    
339
    bs->read_only = 0;
340
    bs->is_temporary = 0;
341
    bs->encrypted = 0;
342

    
343
    if (flags & BDRV_O_SNAPSHOT) {
344
        BlockDriverState *bs1;
345
        int64_t total_size;
346
        int is_protocol = 0;
347

    
348
        /* if snapshot, we create a temporary backing file and open it
349
           instead of opening 'filename' directly */
350

    
351
        /* if there is a backing file, use it */
352
        bs1 = bdrv_new("");
353
        if (!bs1) {
354
            return -ENOMEM;
355
        }
356
        if (bdrv_open(bs1, filename, 0) < 0) {
357
            bdrv_delete(bs1);
358
            return -1;
359
        }
360
        total_size = bdrv_getlength(bs1) >> SECTOR_BITS;
361

    
362
        if (bs1->drv && bs1->drv->protocol_name)
363
            is_protocol = 1;
364

    
365
        bdrv_delete(bs1);
366

    
367
        get_tmp_filename(tmp_filename, sizeof(tmp_filename));
368

    
369
        /* Real path is meaningless for protocols */
370
        if (is_protocol)
371
            snprintf(backing_filename, sizeof(backing_filename),
372
                     "%s", filename);
373
        else
374
            realpath(filename, backing_filename);
375

    
376
        if (bdrv_create(&bdrv_qcow2, tmp_filename,
377
                        total_size, backing_filename, 0) < 0) {
378
            return -1;
379
        }
380
        filename = tmp_filename;
381
        bs->is_temporary = 1;
382
    }
383

    
384
    pstrcpy(bs->filename, sizeof(bs->filename), filename);
385
    if (flags & BDRV_O_FILE) {
386
        drv = find_protocol(filename);
387
        if (!drv)
388
            return -ENOENT;
389
    } else {
390
        if (!drv) {
391
            drv = find_image_format(filename);
392
            if (!drv)
393
                return -1;
394
        }
395
    }
396
    bs->drv = drv;
397
    bs->opaque = qemu_mallocz(drv->instance_size);
398
    if (bs->opaque == NULL && drv->instance_size > 0)
399
        return -1;
400
    /* Note: for compatibility, we open disk image files as RDWR, and
401
       RDONLY as fallback */
402
    if (!(flags & BDRV_O_FILE))
403
        open_flags = BDRV_O_RDWR | (flags & BDRV_O_CACHE_MASK);
404
    else
405
        open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
406
    ret = drv->bdrv_open(bs, filename, open_flags);
407
    if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) {
408
        ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR);
409
        bs->read_only = 1;
410
    }
411
    if (ret < 0) {
412
        qemu_free(bs->opaque);
413
        bs->opaque = NULL;
414
        bs->drv = NULL;
415
        return ret;
416
    }
417
    if (drv->bdrv_getlength) {
418
        bs->total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
419
    }
420
#ifndef _WIN32
421
    if (bs->is_temporary) {
422
        unlink(filename);
423
    }
424
#endif
425
    if (bs->backing_file[0] != '\0') {
426
        /* if there is a backing file, use it */
427
        bs->backing_hd = bdrv_new("");
428
        if (!bs->backing_hd) {
429
        fail:
430
            bdrv_close(bs);
431
            return -ENOMEM;
432
        }
433
        path_combine(backing_filename, sizeof(backing_filename),
434
                     filename, bs->backing_file);
435
        if (bdrv_open(bs->backing_hd, backing_filename, open_flags) < 0)
436
            goto fail;
437
    }
438

    
439
    /* call the change callback */
440
    bs->media_changed = 1;
441
    if (bs->change_cb)
442
        bs->change_cb(bs->change_opaque);
443

    
444
    return 0;
445
}
446

    
447
void bdrv_close(BlockDriverState *bs)
448
{
449
    if (bs->drv) {
450
        if (bs->backing_hd)
451
            bdrv_delete(bs->backing_hd);
452
        bs->drv->bdrv_close(bs);
453
        qemu_free(bs->opaque);
454
#ifdef _WIN32
455
        if (bs->is_temporary) {
456
            unlink(bs->filename);
457
        }
458
#endif
459
        bs->opaque = NULL;
460
        bs->drv = NULL;
461

    
462
        /* call the change callback */
463
        bs->media_changed = 1;
464
        if (bs->change_cb)
465
            bs->change_cb(bs->change_opaque);
466
    }
467
}
468

    
469
void bdrv_delete(BlockDriverState *bs)
470
{
471
    BlockDriverState **pbs;
472

    
473
    pbs = &bdrv_first;
474
    while (*pbs != bs && *pbs != NULL)
475
        pbs = &(*pbs)->next;
476
    if (*pbs == bs)
477
        *pbs = bs->next;
478

    
479
    bdrv_close(bs);
480
    qemu_free(bs);
481
}
482

    
483
/* commit COW file into the raw image */
484
int bdrv_commit(BlockDriverState *bs)
485
{
486
    BlockDriver *drv = bs->drv;
487
    int64_t i, total_sectors;
488
    int n, j;
489
    unsigned char sector[512];
490

    
491
    if (!drv)
492
        return -ENOMEDIUM;
493

    
494
    if (bs->read_only) {
495
        return -EACCES;
496
    }
497

    
498
    if (!bs->backing_hd) {
499
        return -ENOTSUP;
500
    }
501

    
502
    total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
503
    for (i = 0; i < total_sectors;) {
504
        if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
505
            for(j = 0; j < n; j++) {
506
                if (bdrv_read(bs, i, sector, 1) != 0) {
507
                    return -EIO;
508
                }
509

    
510
                if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
511
                    return -EIO;
512
                }
513
                i++;
514
            }
515
        } else {
516
            i += n;
517
        }
518
    }
519

    
520
    if (drv->bdrv_make_empty)
521
        return drv->bdrv_make_empty(bs);
522

    
523
    return 0;
524
}
525

    
526
/* return < 0 if error. See bdrv_write() for the return codes */
527
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
528
              uint8_t *buf, int nb_sectors)
529
{
530
    BlockDriver *drv = bs->drv;
531

    
532
    if (!drv)
533
        return -ENOMEDIUM;
534

    
535
    if (drv->bdrv_pread) {
536
        int ret, len;
537
        len = nb_sectors * 512;
538
        ret = drv->bdrv_pread(bs, sector_num * 512, buf, len);
539
        if (ret < 0)
540
            return ret;
541
        else if (ret != len)
542
            return -EINVAL;
543
        else {
544
            bs->rd_bytes += (unsigned) len;
545
            bs->rd_ops ++;
546
            return 0;
547
        }
548
    } else {
549
        return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
550
    }
551
}
552

    
553
/* Return < 0 if error. Important errors are:
554
  -EIO         generic I/O error (may happen for all errors)
555
  -ENOMEDIUM   No media inserted.
556
  -EINVAL      Invalid sector number or nb_sectors
557
  -EACCES      Trying to write a read-only device
558
*/
559
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
560
               const uint8_t *buf, int nb_sectors)
561
{
562
    BlockDriver *drv = bs->drv;
563
    if (!bs->drv)
564
        return -ENOMEDIUM;
565
    if (bs->read_only)
566
        return -EACCES;
567
    if (drv->bdrv_pwrite) {
568
        int ret, len;
569
        len = nb_sectors * 512;
570
        ret = drv->bdrv_pwrite(bs, sector_num * 512, buf, len);
571
        if (ret < 0)
572
            return ret;
573
        else if (ret != len)
574
            return -EIO;
575
        else {
576
            bs->wr_bytes += (unsigned) len;
577
            bs->wr_ops ++;
578
            return 0;
579
        }
580
    } else {
581
        return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
582
    }
583
}
584

    
585
static int bdrv_pread_em(BlockDriverState *bs, int64_t offset,
586
                         uint8_t *buf, int count1)
587
{
588
    uint8_t tmp_buf[SECTOR_SIZE];
589
    int len, nb_sectors, count;
590
    int64_t sector_num;
591

    
592
    count = count1;
593
    /* first read to align to sector start */
594
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
595
    if (len > count)
596
        len = count;
597
    sector_num = offset >> SECTOR_BITS;
598
    if (len > 0) {
599
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
600
            return -EIO;
601
        memcpy(buf, tmp_buf + (offset & (SECTOR_SIZE - 1)), len);
602
        count -= len;
603
        if (count == 0)
604
            return count1;
605
        sector_num++;
606
        buf += len;
607
    }
608

    
609
    /* read the sectors "in place" */
610
    nb_sectors = count >> SECTOR_BITS;
611
    if (nb_sectors > 0) {
612
        if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0)
613
            return -EIO;
614
        sector_num += nb_sectors;
615
        len = nb_sectors << SECTOR_BITS;
616
        buf += len;
617
        count -= len;
618
    }
619

    
620
    /* add data from the last sector */
621
    if (count > 0) {
622
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
623
            return -EIO;
624
        memcpy(buf, tmp_buf, count);
625
    }
626
    return count1;
627
}
628

    
629
static int bdrv_pwrite_em(BlockDriverState *bs, int64_t offset,
630
                          const uint8_t *buf, int count1)
631
{
632
    uint8_t tmp_buf[SECTOR_SIZE];
633
    int len, nb_sectors, count;
634
    int64_t sector_num;
635

    
636
    count = count1;
637
    /* first write to align to sector start */
638
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
639
    if (len > count)
640
        len = count;
641
    sector_num = offset >> SECTOR_BITS;
642
    if (len > 0) {
643
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
644
            return -EIO;
645
        memcpy(tmp_buf + (offset & (SECTOR_SIZE - 1)), buf, len);
646
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
647
            return -EIO;
648
        count -= len;
649
        if (count == 0)
650
            return count1;
651
        sector_num++;
652
        buf += len;
653
    }
654

    
655
    /* write the sectors "in place" */
656
    nb_sectors = count >> SECTOR_BITS;
657
    if (nb_sectors > 0) {
658
        if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
659
            return -EIO;
660
        sector_num += nb_sectors;
661
        len = nb_sectors << SECTOR_BITS;
662
        buf += len;
663
        count -= len;
664
    }
665

    
666
    /* add data from the last sector */
667
    if (count > 0) {
668
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
669
            return -EIO;
670
        memcpy(tmp_buf, buf, count);
671
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
672
            return -EIO;
673
    }
674
    return count1;
675
}
676

    
677
/**
678
 * Read with byte offsets (needed only for file protocols)
679
 */
680
int bdrv_pread(BlockDriverState *bs, int64_t offset,
681
               void *buf1, int count1)
682
{
683
    BlockDriver *drv = bs->drv;
684

    
685
    if (!drv)
686
        return -ENOMEDIUM;
687
    if (!drv->bdrv_pread)
688
        return bdrv_pread_em(bs, offset, buf1, count1);
689
    return drv->bdrv_pread(bs, offset, buf1, count1);
690
}
691

    
692
/**
693
 * Write with byte offsets (needed only for file protocols)
694
 */
695
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
696
                const void *buf1, int count1)
697
{
698
    BlockDriver *drv = bs->drv;
699

    
700
    if (!drv)
701
        return -ENOMEDIUM;
702
    if (!drv->bdrv_pwrite)
703
        return bdrv_pwrite_em(bs, offset, buf1, count1);
704
    return drv->bdrv_pwrite(bs, offset, buf1, count1);
705
}
706

    
707
/**
708
 * Truncate file to 'offset' bytes (needed only for file protocols)
709
 */
710
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
711
{
712
    BlockDriver *drv = bs->drv;
713
    if (!drv)
714
        return -ENOMEDIUM;
715
    if (!drv->bdrv_truncate)
716
        return -ENOTSUP;
717
    return drv->bdrv_truncate(bs, offset);
718
}
719

    
720
/**
721
 * Length of a file in bytes. Return < 0 if error or unknown.
722
 */
723
int64_t bdrv_getlength(BlockDriverState *bs)
724
{
725
    BlockDriver *drv = bs->drv;
726
    if (!drv)
727
        return -ENOMEDIUM;
728
    if (!drv->bdrv_getlength) {
729
        /* legacy mode */
730
        return bs->total_sectors * SECTOR_SIZE;
731
    }
732
    return drv->bdrv_getlength(bs);
733
}
734

    
735
/* return 0 as number of sectors if no device present or error */
736
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
737
{
738
    int64_t length;
739
    length = bdrv_getlength(bs);
740
    if (length < 0)
741
        length = 0;
742
    else
743
        length = length >> SECTOR_BITS;
744
    *nb_sectors_ptr = length;
745
}
746

    
747
struct partition {
748
        uint8_t boot_ind;           /* 0x80 - active */
749
        uint8_t head;               /* starting head */
750
        uint8_t sector;             /* starting sector */
751
        uint8_t cyl;                /* starting cylinder */
752
        uint8_t sys_ind;            /* What partition type */
753
        uint8_t end_head;           /* end head */
754
        uint8_t end_sector;         /* end sector */
755
        uint8_t end_cyl;            /* end cylinder */
756
        uint32_t start_sect;        /* starting sector counting from 0 */
757
        uint32_t nr_sects;          /* nr of sectors in partition */
758
} __attribute__((packed));
759

    
760
/* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
761
static int guess_disk_lchs(BlockDriverState *bs,
762
                           int *pcylinders, int *pheads, int *psectors)
763
{
764
    uint8_t buf[512];
765
    int ret, i, heads, sectors, cylinders;
766
    struct partition *p;
767
    uint32_t nr_sects;
768
    uint64_t nb_sectors;
769

    
770
    bdrv_get_geometry(bs, &nb_sectors);
771

    
772
    ret = bdrv_read(bs, 0, buf, 1);
773
    if (ret < 0)
774
        return -1;
775
    /* test msdos magic */
776
    if (buf[510] != 0x55 || buf[511] != 0xaa)
777
        return -1;
778
    for(i = 0; i < 4; i++) {
779
        p = ((struct partition *)(buf + 0x1be)) + i;
780
        nr_sects = le32_to_cpu(p->nr_sects);
781
        if (nr_sects && p->end_head) {
782
            /* We make the assumption that the partition terminates on
783
               a cylinder boundary */
784
            heads = p->end_head + 1;
785
            sectors = p->end_sector & 63;
786
            if (sectors == 0)
787
                continue;
788
            cylinders = nb_sectors / (heads * sectors);
789
            if (cylinders < 1 || cylinders > 16383)
790
                continue;
791
            *pheads = heads;
792
            *psectors = sectors;
793
            *pcylinders = cylinders;
794
#if 0
795
            printf("guessed geometry: LCHS=%d %d %d\n",
796
                   cylinders, heads, sectors);
797
#endif
798
            return 0;
799
        }
800
    }
801
    return -1;
802
}
803

    
804
void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
805
{
806
    int translation, lba_detected = 0;
807
    int cylinders, heads, secs;
808
    uint64_t nb_sectors;
809

    
810
    /* if a geometry hint is available, use it */
811
    bdrv_get_geometry(bs, &nb_sectors);
812
    bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
813
    translation = bdrv_get_translation_hint(bs);
814
    if (cylinders != 0) {
815
        *pcyls = cylinders;
816
        *pheads = heads;
817
        *psecs = secs;
818
    } else {
819
        if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
820
            if (heads > 16) {
821
                /* if heads > 16, it means that a BIOS LBA
822
                   translation was active, so the default
823
                   hardware geometry is OK */
824
                lba_detected = 1;
825
                goto default_geometry;
826
            } else {
827
                *pcyls = cylinders;
828
                *pheads = heads;
829
                *psecs = secs;
830
                /* disable any translation to be in sync with
831
                   the logical geometry */
832
                if (translation == BIOS_ATA_TRANSLATION_AUTO) {
833
                    bdrv_set_translation_hint(bs,
834
                                              BIOS_ATA_TRANSLATION_NONE);
835
                }
836
            }
837
        } else {
838
        default_geometry:
839
            /* if no geometry, use a standard physical disk geometry */
840
            cylinders = nb_sectors / (16 * 63);
841

    
842
            if (cylinders > 16383)
843
                cylinders = 16383;
844
            else if (cylinders < 2)
845
                cylinders = 2;
846
            *pcyls = cylinders;
847
            *pheads = 16;
848
            *psecs = 63;
849
            if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
850
                if ((*pcyls * *pheads) <= 131072) {
851
                    bdrv_set_translation_hint(bs,
852
                                              BIOS_ATA_TRANSLATION_LARGE);
853
                } else {
854
                    bdrv_set_translation_hint(bs,
855
                                              BIOS_ATA_TRANSLATION_LBA);
856
                }
857
            }
858
        }
859
        bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
860
    }
861
}
862

    
863
void bdrv_set_geometry_hint(BlockDriverState *bs,
864
                            int cyls, int heads, int secs)
865
{
866
    bs->cyls = cyls;
867
    bs->heads = heads;
868
    bs->secs = secs;
869
}
870

    
871
void bdrv_set_type_hint(BlockDriverState *bs, int type)
872
{
873
    bs->type = type;
874
    bs->removable = ((type == BDRV_TYPE_CDROM ||
875
                      type == BDRV_TYPE_FLOPPY));
876
}
877

    
878
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
879
{
880
    bs->translation = translation;
881
}
882

    
883
void bdrv_get_geometry_hint(BlockDriverState *bs,
884
                            int *pcyls, int *pheads, int *psecs)
885
{
886
    *pcyls = bs->cyls;
887
    *pheads = bs->heads;
888
    *psecs = bs->secs;
889
}
890

    
891
int bdrv_get_type_hint(BlockDriverState *bs)
892
{
893
    return bs->type;
894
}
895

    
896
int bdrv_get_translation_hint(BlockDriverState *bs)
897
{
898
    return bs->translation;
899
}
900

    
901
int bdrv_is_removable(BlockDriverState *bs)
902
{
903
    return bs->removable;
904
}
905

    
906
int bdrv_is_read_only(BlockDriverState *bs)
907
{
908
    return bs->read_only;
909
}
910

    
911
int bdrv_is_sg(BlockDriverState *bs)
912
{
913
    return bs->sg;
914
}
915

    
916
/* XXX: no longer used */
917
void bdrv_set_change_cb(BlockDriverState *bs,
918
                        void (*change_cb)(void *opaque), void *opaque)
919
{
920
    bs->change_cb = change_cb;
921
    bs->change_opaque = opaque;
922
}
923

    
924
int bdrv_is_encrypted(BlockDriverState *bs)
925
{
926
    if (bs->backing_hd && bs->backing_hd->encrypted)
927
        return 1;
928
    return bs->encrypted;
929
}
930

    
931
int bdrv_set_key(BlockDriverState *bs, const char *key)
932
{
933
    int ret;
934
    if (bs->backing_hd && bs->backing_hd->encrypted) {
935
        ret = bdrv_set_key(bs->backing_hd, key);
936
        if (ret < 0)
937
            return ret;
938
        if (!bs->encrypted)
939
            return 0;
940
    }
941
    if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
942
        return -1;
943
    return bs->drv->bdrv_set_key(bs, key);
944
}
945

    
946
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
947
{
948
    if (!bs->drv) {
949
        buf[0] = '\0';
950
    } else {
951
        pstrcpy(buf, buf_size, bs->drv->format_name);
952
    }
953
}
954

    
955
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
956
                         void *opaque)
957
{
958
    BlockDriver *drv;
959

    
960
    for (drv = first_drv; drv != NULL; drv = drv->next) {
961
        it(opaque, drv->format_name);
962
    }
963
}
964

    
965
BlockDriverState *bdrv_find(const char *name)
966
{
967
    BlockDriverState *bs;
968

    
969
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
970
        if (!strcmp(name, bs->device_name))
971
            return bs;
972
    }
973
    return NULL;
974
}
975

    
976
void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque)
977
{
978
    BlockDriverState *bs;
979

    
980
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
981
        it(opaque, bs->device_name);
982
    }
983
}
984

    
985
const char *bdrv_get_device_name(BlockDriverState *bs)
986
{
987
    return bs->device_name;
988
}
989

    
990
void bdrv_flush(BlockDriverState *bs)
991
{
992
    if (bs->drv->bdrv_flush)
993
        bs->drv->bdrv_flush(bs);
994
    if (bs->backing_hd)
995
        bdrv_flush(bs->backing_hd);
996
}
997

    
998
void bdrv_flush_all(void)
999
{
1000
    BlockDriverState *bs;
1001

    
1002
    for (bs = bdrv_first; bs != NULL; bs = bs->next)
1003
        if (bs->drv && !bdrv_is_read_only(bs) && 
1004
            (!bdrv_is_removable(bs) || bdrv_is_inserted(bs)))
1005
            bdrv_flush(bs);
1006
}
1007

    
1008
/*
1009
 * Returns true iff the specified sector is present in the disk image. Drivers
1010
 * not implementing the functionality are assumed to not support backing files,
1011
 * hence all their sectors are reported as allocated.
1012
 *
1013
 * 'pnum' is set to the number of sectors (including and immediately following
1014
 * the specified sector) that are known to be in the same
1015
 * allocated/unallocated state.
1016
 *
1017
 * 'nb_sectors' is the max value 'pnum' should be set to.
1018
 */
1019
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
1020
        int *pnum)
1021
{
1022
    int64_t n;
1023
    if (!bs->drv->bdrv_is_allocated) {
1024
        if (sector_num >= bs->total_sectors) {
1025
            *pnum = 0;
1026
            return 0;
1027
        }
1028
        n = bs->total_sectors - sector_num;
1029
        *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
1030
        return 1;
1031
    }
1032
    return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
1033
}
1034

    
1035
void bdrv_info(void)
1036
{
1037
    BlockDriverState *bs;
1038

    
1039
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1040
        term_printf("%s:", bs->device_name);
1041
        term_printf(" type=");
1042
        switch(bs->type) {
1043
        case BDRV_TYPE_HD:
1044
            term_printf("hd");
1045
            break;
1046
        case BDRV_TYPE_CDROM:
1047
            term_printf("cdrom");
1048
            break;
1049
        case BDRV_TYPE_FLOPPY:
1050
            term_printf("floppy");
1051
            break;
1052
        }
1053
        term_printf(" removable=%d", bs->removable);
1054
        if (bs->removable) {
1055
            term_printf(" locked=%d", bs->locked);
1056
        }
1057
        if (bs->drv) {
1058
            term_printf(" file=");
1059
            term_print_filename(bs->filename);
1060
            if (bs->backing_file[0] != '\0') {
1061
                term_printf(" backing_file=");
1062
                term_print_filename(bs->backing_file);
1063
            }
1064
            term_printf(" ro=%d", bs->read_only);
1065
            term_printf(" drv=%s", bs->drv->format_name);
1066
            if (bs->encrypted)
1067
                term_printf(" encrypted");
1068
        } else {
1069
            term_printf(" [not inserted]");
1070
        }
1071
        term_printf("\n");
1072
    }
1073
}
1074

    
1075
/* The "info blockstats" command. */
1076
void bdrv_info_stats (void)
1077
{
1078
    BlockDriverState *bs;
1079

    
1080
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1081
        term_printf ("%s:"
1082
                     " rd_bytes=%" PRIu64
1083
                     " wr_bytes=%" PRIu64
1084
                     " rd_operations=%" PRIu64
1085
                     " wr_operations=%" PRIu64
1086
                     "\n",
1087
                     bs->device_name,
1088
                     bs->rd_bytes, bs->wr_bytes,
1089
                     bs->rd_ops, bs->wr_ops);
1090
    }
1091
}
1092

    
1093
void bdrv_get_backing_filename(BlockDriverState *bs,
1094
                               char *filename, int filename_size)
1095
{
1096
    if (!bs->backing_hd) {
1097
        pstrcpy(filename, filename_size, "");
1098
    } else {
1099
        pstrcpy(filename, filename_size, bs->backing_file);
1100
    }
1101
}
1102

    
1103
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
1104
                          const uint8_t *buf, int nb_sectors)
1105
{
1106
    BlockDriver *drv = bs->drv;
1107
    if (!drv)
1108
        return -ENOMEDIUM;
1109
    if (!drv->bdrv_write_compressed)
1110
        return -ENOTSUP;
1111
    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
1112
}
1113

    
1114
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1115
{
1116
    BlockDriver *drv = bs->drv;
1117
    if (!drv)
1118
        return -ENOMEDIUM;
1119
    if (!drv->bdrv_get_info)
1120
        return -ENOTSUP;
1121
    memset(bdi, 0, sizeof(*bdi));
1122
    return drv->bdrv_get_info(bs, bdi);
1123
}
1124

    
1125
/**************************************************************/
1126
/* handling of snapshots */
1127

    
1128
int bdrv_snapshot_create(BlockDriverState *bs,
1129
                         QEMUSnapshotInfo *sn_info)
1130
{
1131
    BlockDriver *drv = bs->drv;
1132
    if (!drv)
1133
        return -ENOMEDIUM;
1134
    if (!drv->bdrv_snapshot_create)
1135
        return -ENOTSUP;
1136
    return drv->bdrv_snapshot_create(bs, sn_info);
1137
}
1138

    
1139
int bdrv_snapshot_goto(BlockDriverState *bs,
1140
                       const char *snapshot_id)
1141
{
1142
    BlockDriver *drv = bs->drv;
1143
    if (!drv)
1144
        return -ENOMEDIUM;
1145
    if (!drv->bdrv_snapshot_goto)
1146
        return -ENOTSUP;
1147
    return drv->bdrv_snapshot_goto(bs, snapshot_id);
1148
}
1149

    
1150
int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
1151
{
1152
    BlockDriver *drv = bs->drv;
1153
    if (!drv)
1154
        return -ENOMEDIUM;
1155
    if (!drv->bdrv_snapshot_delete)
1156
        return -ENOTSUP;
1157
    return drv->bdrv_snapshot_delete(bs, snapshot_id);
1158
}
1159

    
1160
int bdrv_snapshot_list(BlockDriverState *bs,
1161
                       QEMUSnapshotInfo **psn_info)
1162
{
1163
    BlockDriver *drv = bs->drv;
1164
    if (!drv)
1165
        return -ENOMEDIUM;
1166
    if (!drv->bdrv_snapshot_list)
1167
        return -ENOTSUP;
1168
    return drv->bdrv_snapshot_list(bs, psn_info);
1169
}
1170

    
1171
#define NB_SUFFIXES 4
1172

    
1173
char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1174
{
1175
    static const char suffixes[NB_SUFFIXES] = "KMGT";
1176
    int64_t base;
1177
    int i;
1178

    
1179
    if (size <= 999) {
1180
        snprintf(buf, buf_size, "%" PRId64, size);
1181
    } else {
1182
        base = 1024;
1183
        for(i = 0; i < NB_SUFFIXES; i++) {
1184
            if (size < (10 * base)) {
1185
                snprintf(buf, buf_size, "%0.1f%c",
1186
                         (double)size / base,
1187
                         suffixes[i]);
1188
                break;
1189
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1190
                snprintf(buf, buf_size, "%" PRId64 "%c",
1191
                         ((size + (base >> 1)) / base),
1192
                         suffixes[i]);
1193
                break;
1194
            }
1195
            base = base * 1024;
1196
        }
1197
    }
1198
    return buf;
1199
}
1200

    
1201
char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1202
{
1203
    char buf1[128], date_buf[128], clock_buf[128];
1204
#ifdef _WIN32
1205
    struct tm *ptm;
1206
#else
1207
    struct tm tm;
1208
#endif
1209
    time_t ti;
1210
    int64_t secs;
1211

    
1212
    if (!sn) {
1213
        snprintf(buf, buf_size,
1214
                 "%-10s%-20s%7s%20s%15s",
1215
                 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1216
    } else {
1217
        ti = sn->date_sec;
1218
#ifdef _WIN32
1219
        ptm = localtime(&ti);
1220
        strftime(date_buf, sizeof(date_buf),
1221
                 "%Y-%m-%d %H:%M:%S", ptm);
1222
#else
1223
        localtime_r(&ti, &tm);
1224
        strftime(date_buf, sizeof(date_buf),
1225
                 "%Y-%m-%d %H:%M:%S", &tm);
1226
#endif
1227
        secs = sn->vm_clock_nsec / 1000000000;
1228
        snprintf(clock_buf, sizeof(clock_buf),
1229
                 "%02d:%02d:%02d.%03d",
1230
                 (int)(secs / 3600),
1231
                 (int)((secs / 60) % 60),
1232
                 (int)(secs % 60),
1233
                 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1234
        snprintf(buf, buf_size,
1235
                 "%-10s%-20s%7s%20s%15s",
1236
                 sn->id_str, sn->name,
1237
                 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1238
                 date_buf,
1239
                 clock_buf);
1240
    }
1241
    return buf;
1242
}
1243

    
1244

    
1245
/**************************************************************/
1246
/* async I/Os */
1247

    
1248
BlockDriverAIOCB *bdrv_aio_read(BlockDriverState *bs, int64_t sector_num,
1249
                                uint8_t *buf, int nb_sectors,
1250
                                BlockDriverCompletionFunc *cb, void *opaque)
1251
{
1252
    BlockDriver *drv = bs->drv;
1253
    BlockDriverAIOCB *ret;
1254

    
1255
    if (!drv)
1256
        return NULL;
1257

    
1258
    ret = drv->bdrv_aio_read(bs, sector_num, buf, nb_sectors, cb, opaque);
1259

    
1260
    if (ret) {
1261
        /* Update stats even though technically transfer has not happened. */
1262
        bs->rd_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1263
        bs->rd_ops ++;
1264
    }
1265

    
1266
    return ret;
1267
}
1268

    
1269
BlockDriverAIOCB *bdrv_aio_write(BlockDriverState *bs, int64_t sector_num,
1270
                                 const uint8_t *buf, int nb_sectors,
1271
                                 BlockDriverCompletionFunc *cb, void *opaque)
1272
{
1273
    BlockDriver *drv = bs->drv;
1274
    BlockDriverAIOCB *ret;
1275

    
1276
    if (!drv)
1277
        return NULL;
1278
    if (bs->read_only)
1279
        return NULL;
1280

    
1281
    ret = drv->bdrv_aio_write(bs, sector_num, buf, nb_sectors, cb, opaque);
1282

    
1283
    if (ret) {
1284
        /* Update stats even though technically transfer has not happened. */
1285
        bs->wr_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1286
        bs->wr_ops ++;
1287
    }
1288

    
1289
    return ret;
1290
}
1291

    
1292
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1293
{
1294
    BlockDriver *drv = acb->bs->drv;
1295

    
1296
    drv->bdrv_aio_cancel(acb);
1297
}
1298

    
1299

    
1300
/**************************************************************/
1301
/* async block device emulation */
1302

    
1303
static void bdrv_aio_bh_cb(void *opaque)
1304
{
1305
    BlockDriverAIOCBSync *acb = opaque;
1306
    acb->common.cb(acb->common.opaque, acb->ret);
1307
    qemu_aio_release(acb);
1308
}
1309

    
1310
static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
1311
        int64_t sector_num, uint8_t *buf, int nb_sectors,
1312
        BlockDriverCompletionFunc *cb, void *opaque)
1313
{
1314
    BlockDriverAIOCBSync *acb;
1315
    int ret;
1316

    
1317
    acb = qemu_aio_get(bs, cb, opaque);
1318
    if (!acb->bh)
1319
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1320
    ret = bdrv_read(bs, sector_num, buf, nb_sectors);
1321
    acb->ret = ret;
1322
    qemu_bh_schedule(acb->bh);
1323
    return &acb->common;
1324
}
1325

    
1326
static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
1327
        int64_t sector_num, const uint8_t *buf, int nb_sectors,
1328
        BlockDriverCompletionFunc *cb, void *opaque)
1329
{
1330
    BlockDriverAIOCBSync *acb;
1331
    int ret;
1332

    
1333
    acb = qemu_aio_get(bs, cb, opaque);
1334
    if (!acb->bh)
1335
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1336
    ret = bdrv_write(bs, sector_num, buf, nb_sectors);
1337
    acb->ret = ret;
1338
    qemu_bh_schedule(acb->bh);
1339
    return &acb->common;
1340
}
1341

    
1342
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1343
{
1344
    BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1345
    qemu_bh_cancel(acb->bh);
1346
    qemu_aio_release(acb);
1347
}
1348

    
1349
/**************************************************************/
1350
/* sync block device emulation */
1351

    
1352
static void bdrv_rw_em_cb(void *opaque, int ret)
1353
{
1354
    *(int *)opaque = ret;
1355
}
1356

    
1357
#define NOT_DONE 0x7fffffff
1358

    
1359
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1360
                        uint8_t *buf, int nb_sectors)
1361
{
1362
    int async_ret;
1363
    BlockDriverAIOCB *acb;
1364

    
1365
    async_ret = NOT_DONE;
1366
    acb = bdrv_aio_read(bs, sector_num, buf, nb_sectors,
1367
                        bdrv_rw_em_cb, &async_ret);
1368
    if (acb == NULL)
1369
        return -1;
1370

    
1371
    while (async_ret == NOT_DONE) {
1372
        qemu_aio_wait();
1373
    }
1374

    
1375
    return async_ret;
1376
}
1377

    
1378
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1379
                         const uint8_t *buf, int nb_sectors)
1380
{
1381
    int async_ret;
1382
    BlockDriverAIOCB *acb;
1383

    
1384
    async_ret = NOT_DONE;
1385
    acb = bdrv_aio_write(bs, sector_num, buf, nb_sectors,
1386
                         bdrv_rw_em_cb, &async_ret);
1387
    if (acb == NULL)
1388
        return -1;
1389
    while (async_ret == NOT_DONE) {
1390
        qemu_aio_wait();
1391
    }
1392
    return async_ret;
1393
}
1394

    
1395
void bdrv_init(void)
1396
{
1397
    bdrv_register(&bdrv_raw);
1398
    bdrv_register(&bdrv_host_device);
1399
#ifndef _WIN32
1400
    bdrv_register(&bdrv_cow);
1401
#endif
1402
    bdrv_register(&bdrv_qcow);
1403
    bdrv_register(&bdrv_vmdk);
1404
    bdrv_register(&bdrv_cloop);
1405
    bdrv_register(&bdrv_dmg);
1406
    bdrv_register(&bdrv_bochs);
1407
    bdrv_register(&bdrv_vpc);
1408
    bdrv_register(&bdrv_vvfat);
1409
    bdrv_register(&bdrv_qcow2);
1410
    bdrv_register(&bdrv_parallels);
1411
    bdrv_register(&bdrv_nbd);
1412
}
1413

    
1414
void *qemu_aio_get(BlockDriverState *bs, BlockDriverCompletionFunc *cb,
1415
                   void *opaque)
1416
{
1417
    BlockDriver *drv;
1418
    BlockDriverAIOCB *acb;
1419

    
1420
    drv = bs->drv;
1421
    if (drv->free_aiocb) {
1422
        acb = drv->free_aiocb;
1423
        drv->free_aiocb = acb->next;
1424
    } else {
1425
        acb = qemu_mallocz(drv->aiocb_size);
1426
        if (!acb)
1427
            return NULL;
1428
    }
1429
    acb->bs = bs;
1430
    acb->cb = cb;
1431
    acb->opaque = opaque;
1432
    return acb;
1433
}
1434

    
1435
void qemu_aio_release(void *p)
1436
{
1437
    BlockDriverAIOCB *acb = p;
1438
    BlockDriver *drv = acb->bs->drv;
1439
    acb->next = drv->free_aiocb;
1440
    drv->free_aiocb = acb;
1441
}
1442

    
1443
/**************************************************************/
1444
/* removable device support */
1445

    
1446
/**
1447
 * Return TRUE if the media is present
1448
 */
1449
int bdrv_is_inserted(BlockDriverState *bs)
1450
{
1451
    BlockDriver *drv = bs->drv;
1452
    int ret;
1453
    if (!drv)
1454
        return 0;
1455
    if (!drv->bdrv_is_inserted)
1456
        return 1;
1457
    ret = drv->bdrv_is_inserted(bs);
1458
    return ret;
1459
}
1460

    
1461
/**
1462
 * Return TRUE if the media changed since the last call to this
1463
 * function. It is currently only used for floppy disks
1464
 */
1465
int bdrv_media_changed(BlockDriverState *bs)
1466
{
1467
    BlockDriver *drv = bs->drv;
1468
    int ret;
1469

    
1470
    if (!drv || !drv->bdrv_media_changed)
1471
        ret = -ENOTSUP;
1472
    else
1473
        ret = drv->bdrv_media_changed(bs);
1474
    if (ret == -ENOTSUP)
1475
        ret = bs->media_changed;
1476
    bs->media_changed = 0;
1477
    return ret;
1478
}
1479

    
1480
/**
1481
 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
1482
 */
1483
void bdrv_eject(BlockDriverState *bs, int eject_flag)
1484
{
1485
    BlockDriver *drv = bs->drv;
1486
    int ret;
1487

    
1488
    if (!drv || !drv->bdrv_eject) {
1489
        ret = -ENOTSUP;
1490
    } else {
1491
        ret = drv->bdrv_eject(bs, eject_flag);
1492
    }
1493
    if (ret == -ENOTSUP) {
1494
        if (eject_flag)
1495
            bdrv_close(bs);
1496
    }
1497
}
1498

    
1499
int bdrv_is_locked(BlockDriverState *bs)
1500
{
1501
    return bs->locked;
1502
}
1503

    
1504
/**
1505
 * Lock or unlock the media (if it is locked, the user won't be able
1506
 * to eject it manually).
1507
 */
1508
void bdrv_set_locked(BlockDriverState *bs, int locked)
1509
{
1510
    BlockDriver *drv = bs->drv;
1511

    
1512
    bs->locked = locked;
1513
    if (drv && drv->bdrv_set_locked) {
1514
        drv->bdrv_set_locked(bs, locked);
1515
    }
1516
}
1517

    
1518
/* needed for generic scsi interface */
1519

    
1520
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
1521
{
1522
    BlockDriver *drv = bs->drv;
1523

    
1524
    if (drv && drv->bdrv_ioctl)
1525
        return drv->bdrv_ioctl(bs, req, buf);
1526
    return -ENOTSUP;
1527
}