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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.
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 *
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-common.h"
25
#ifndef QEMU_IMG
26
#include "console.h"
27
#endif
28
#include "block_int.h"
29

    
30
#ifdef _BSD
31
#include <sys/types.h>
32
#include <sys/stat.h>
33
#include <sys/ioctl.h>
34
#include <sys/queue.h>
35
#include <sys/disk.h>
36
#endif
37

    
38
#define SECTOR_BITS 9
39
#define SECTOR_SIZE (1 << SECTOR_BITS)
40

    
41
typedef struct BlockDriverAIOCBSync {
42
    BlockDriverAIOCB common;
43
    QEMUBH *bh;
44
    int ret;
45
} BlockDriverAIOCBSync;
46

    
47
static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
48
        int64_t sector_num, uint8_t *buf, int nb_sectors,
49
        BlockDriverCompletionFunc *cb, void *opaque);
50
static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
51
        int64_t sector_num, const uint8_t *buf, int nb_sectors,
52
        BlockDriverCompletionFunc *cb, void *opaque);
53
static void bdrv_aio_cancel_em(BlockDriverAIOCB *acb);
54
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
55
                        uint8_t *buf, int nb_sectors);
56
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
57
                         const uint8_t *buf, int nb_sectors);
58

    
59
BlockDriverState *bdrv_first;
60
static BlockDriver *first_drv;
61

    
62
int path_is_absolute(const char *path)
63
{
64
    const char *p;
65
#ifdef _WIN32
66
    /* specific case for names like: "\\.\d:" */
67
    if (*path == '/' || *path == '\\')
68
        return 1;
69
#endif
70
    p = strchr(path, ':');
71
    if (p)
72
        p++;
73
    else
74
        p = path;
75
#ifdef _WIN32
76
    return (*p == '/' || *p == '\\');
77
#else
78
    return (*p == '/');
79
#endif
80
}
81

    
82
/* if filename is absolute, just copy it to dest. Otherwise, build a
83
   path to it by considering it is relative to base_path. URL are
84
   supported. */
85
void path_combine(char *dest, int dest_size,
86
                  const char *base_path,
87
                  const char *filename)
88
{
89
    const char *p, *p1;
90
    int len;
91

    
92
    if (dest_size <= 0)
93
        return;
94
    if (path_is_absolute(filename)) {
95
        pstrcpy(dest, dest_size, filename);
96
    } else {
97
        p = strchr(base_path, ':');
98
        if (p)
99
            p++;
100
        else
101
            p = base_path;
102
        p1 = strrchr(base_path, '/');
103
#ifdef _WIN32
104
        {
105
            const char *p2;
106
            p2 = strrchr(base_path, '\\');
107
            if (!p1 || p2 > p1)
108
                p1 = p2;
109
        }
110
#endif
111
        if (p1)
112
            p1++;
113
        else
114
            p1 = base_path;
115
        if (p1 > p)
116
            p = p1;
117
        len = p - base_path;
118
        if (len > dest_size - 1)
119
            len = dest_size - 1;
120
        memcpy(dest, base_path, len);
121
        dest[len] = '\0';
122
        pstrcat(dest, dest_size, filename);
123
    }
124
}
125

    
126

    
127
static void bdrv_register(BlockDriver *bdrv)
128
{
129
    if (!bdrv->bdrv_aio_read) {
130
        /* add AIO emulation layer */
131
        bdrv->bdrv_aio_read = bdrv_aio_read_em;
132
        bdrv->bdrv_aio_write = bdrv_aio_write_em;
133
        bdrv->bdrv_aio_cancel = bdrv_aio_cancel_em;
134
        bdrv->aiocb_size = sizeof(BlockDriverAIOCBSync);
135
    } else if (!bdrv->bdrv_read && !bdrv->bdrv_pread) {
136
        /* add synchronous IO emulation layer */
137
        bdrv->bdrv_read = bdrv_read_em;
138
        bdrv->bdrv_write = bdrv_write_em;
139
    }
140
    bdrv->next = first_drv;
141
    first_drv = bdrv;
142
}
143

    
144
/* create a new block device (by default it is empty) */
145
BlockDriverState *bdrv_new(const char *device_name)
146
{
147
    BlockDriverState **pbs, *bs;
148

    
149
    bs = qemu_mallocz(sizeof(BlockDriverState));
150
    if(!bs)
151
        return NULL;
152
    pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
153
    if (device_name[0] != '\0') {
154
        /* insert at the end */
155
        pbs = &bdrv_first;
156
        while (*pbs != NULL)
157
            pbs = &(*pbs)->next;
158
        *pbs = bs;
159
    }
160
    return bs;
161
}
162

    
163
BlockDriver *bdrv_find_format(const char *format_name)
164
{
165
    BlockDriver *drv1;
166
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
167
        if (!strcmp(drv1->format_name, format_name))
168
            return drv1;
169
    }
170
    return NULL;
171
}
172

    
173
int bdrv_create(BlockDriver *drv,
174
                const char *filename, int64_t size_in_sectors,
175
                const char *backing_file, int flags)
176
{
177
    if (!drv->bdrv_create)
178
        return -ENOTSUP;
179
    return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
180
}
181

    
182
#ifdef _WIN32
183
void get_tmp_filename(char *filename, int size)
184
{
185
    char temp_dir[MAX_PATH];
186

    
187
    GetTempPath(MAX_PATH, temp_dir);
188
    GetTempFileName(temp_dir, "qem", 0, filename);
189
}
190
#else
191
void get_tmp_filename(char *filename, int size)
192
{
193
    int fd;
194
    /* XXX: race condition possible */
195
    pstrcpy(filename, size, "/tmp/vl.XXXXXX");
196
    fd = mkstemp(filename);
197
    close(fd);
198
}
199
#endif
200

    
201
#ifdef _WIN32
202
static int is_windows_drive_prefix(const char *filename)
203
{
204
    return (((filename[0] >= 'a' && filename[0] <= 'z') ||
205
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
206
            filename[1] == ':');
207
}
208

    
209
static int is_windows_drive(const char *filename)
210
{
211
    if (is_windows_drive_prefix(filename) &&
212
        filename[2] == '\0')
213
        return 1;
214
    if (strstart(filename, "\\\\.\\", NULL) ||
215
        strstart(filename, "//./", NULL))
216
        return 1;
217
    return 0;
218
}
219
#endif
220

    
221
static BlockDriver *find_protocol(const char *filename)
222
{
223
    BlockDriver *drv1;
224
    char protocol[128];
225
    int len;
226
    const char *p;
227

    
228
#ifdef _WIN32
229
    if (is_windows_drive(filename) ||
230
        is_windows_drive_prefix(filename))
231
        return &bdrv_raw;
232
#endif
233
    p = strchr(filename, ':');
234
    if (!p)
235
        return &bdrv_raw;
236
    len = p - filename;
237
    if (len > sizeof(protocol) - 1)
238
        len = sizeof(protocol) - 1;
239
    memcpy(protocol, filename, len);
240
    protocol[len] = '\0';
241
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
242
        if (drv1->protocol_name &&
243
            !strcmp(drv1->protocol_name, protocol))
244
            return drv1;
245
    }
246
    return NULL;
247
}
248

    
249
/* XXX: force raw format if block or character device ? It would
250
   simplify the BSD case */
251
static BlockDriver *find_image_format(const char *filename)
252
{
253
    int ret, score, score_max;
254
    BlockDriver *drv1, *drv;
255
    uint8_t buf[2048];
256
    BlockDriverState *bs;
257

    
258
    /* detect host devices. By convention, /dev/cdrom[N] is always
259
       recognized as a host CDROM */
260
    if (strstart(filename, "/dev/cdrom", NULL))
261
        return &bdrv_host_device;
262
#ifdef _WIN32
263
    if (is_windows_drive(filename))
264
        return &bdrv_host_device;
265
#else
266
    {
267
        struct stat st;
268
        if (stat(filename, &st) >= 0 &&
269
            (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
270
            return &bdrv_host_device;
271
        }
272
    }
273
#endif
274

    
275
    drv = find_protocol(filename);
276
    /* no need to test disk image formats for vvfat */
277
    if (drv == &bdrv_vvfat)
278
        return drv;
279

    
280
    ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
281
    if (ret < 0)
282
        return NULL;
283
    ret = bdrv_pread(bs, 0, buf, sizeof(buf));
284
    bdrv_delete(bs);
285
    if (ret < 0) {
286
        return NULL;
287
    }
288

    
289
    score_max = 0;
290
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
291
        if (drv1->bdrv_probe) {
292
            score = drv1->bdrv_probe(buf, ret, filename);
293
            if (score > score_max) {
294
                score_max = score;
295
                drv = drv1;
296
            }
297
        }
298
    }
299
    return drv;
300
}
301

    
302
int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
303
{
304
    BlockDriverState *bs;
305
    int ret;
306

    
307
    bs = bdrv_new("");
308
    if (!bs)
309
        return -ENOMEM;
310
    ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL);
311
    if (ret < 0) {
312
        bdrv_delete(bs);
313
        return ret;
314
    }
315
    *pbs = bs;
316
    return 0;
317
}
318

    
319
int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
320
{
321
    return bdrv_open2(bs, filename, flags, NULL);
322
}
323

    
324
int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
325
               BlockDriver *drv)
326
{
327
    int ret, open_flags;
328
    char tmp_filename[PATH_MAX];
329
    char backing_filename[PATH_MAX];
330

    
331
    bs->read_only = 0;
332
    bs->is_temporary = 0;
333
    bs->encrypted = 0;
334

    
335
    if (flags & BDRV_O_SNAPSHOT) {
336
        BlockDriverState *bs1;
337
        int64_t total_size;
338

    
339
        /* if snapshot, we create a temporary backing file and open it
340
           instead of opening 'filename' directly */
341

    
342
        /* if there is a backing file, use it */
343
        bs1 = bdrv_new("");
344
        if (!bs1) {
345
            return -ENOMEM;
346
        }
347
        if (bdrv_open(bs1, filename, 0) < 0) {
348
            bdrv_delete(bs1);
349
            return -1;
350
        }
351
        total_size = bdrv_getlength(bs1) >> SECTOR_BITS;
352
        bdrv_delete(bs1);
353

    
354
        get_tmp_filename(tmp_filename, sizeof(tmp_filename));
355
        realpath(filename, backing_filename);
356
        if (bdrv_create(&bdrv_qcow2, tmp_filename,
357
                        total_size, backing_filename, 0) < 0) {
358
            return -1;
359
        }
360
        filename = tmp_filename;
361
        bs->is_temporary = 1;
362
    }
363

    
364
    pstrcpy(bs->filename, sizeof(bs->filename), filename);
365
    if (flags & BDRV_O_FILE) {
366
        drv = find_protocol(filename);
367
        if (!drv)
368
            return -ENOENT;
369
    } else {
370
        if (!drv) {
371
            drv = find_image_format(filename);
372
            if (!drv)
373
                return -1;
374
        }
375
    }
376
    bs->drv = drv;
377
    bs->opaque = qemu_mallocz(drv->instance_size);
378
    if (bs->opaque == NULL && drv->instance_size > 0)
379
        return -1;
380
    /* Note: for compatibility, we open disk image files as RDWR, and
381
       RDONLY as fallback */
382
    if (!(flags & BDRV_O_FILE))
383
        open_flags = BDRV_O_RDWR | (flags & BDRV_O_DIRECT);
384
    else
385
        open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
386
    ret = drv->bdrv_open(bs, filename, open_flags);
387
    if (ret == -EACCES && !(flags & BDRV_O_FILE)) {
388
        ret = drv->bdrv_open(bs, filename, BDRV_O_RDONLY);
389
        bs->read_only = 1;
390
    }
391
    if (ret < 0) {
392
        qemu_free(bs->opaque);
393
        bs->opaque = NULL;
394
        bs->drv = NULL;
395
        return ret;
396
    }
397
    if (drv->bdrv_getlength) {
398
        bs->total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
399
    }
400
#ifndef _WIN32
401
    if (bs->is_temporary) {
402
        unlink(filename);
403
    }
404
#endif
405
    if (bs->backing_file[0] != '\0') {
406
        /* if there is a backing file, use it */
407
        bs->backing_hd = bdrv_new("");
408
        if (!bs->backing_hd) {
409
        fail:
410
            bdrv_close(bs);
411
            return -ENOMEM;
412
        }
413
        path_combine(backing_filename, sizeof(backing_filename),
414
                     filename, bs->backing_file);
415
        if (bdrv_open(bs->backing_hd, backing_filename, 0) < 0)
416
            goto fail;
417
    }
418

    
419
    /* call the change callback */
420
    bs->media_changed = 1;
421
    if (bs->change_cb)
422
        bs->change_cb(bs->change_opaque);
423

    
424
    return 0;
425
}
426

    
427
void bdrv_close(BlockDriverState *bs)
428
{
429
    if (bs->drv) {
430
        if (bs->backing_hd)
431
            bdrv_delete(bs->backing_hd);
432
        bs->drv->bdrv_close(bs);
433
        qemu_free(bs->opaque);
434
#ifdef _WIN32
435
        if (bs->is_temporary) {
436
            unlink(bs->filename);
437
        }
438
#endif
439
        bs->opaque = NULL;
440
        bs->drv = NULL;
441

    
442
        /* call the change callback */
443
        bs->media_changed = 1;
444
        if (bs->change_cb)
445
            bs->change_cb(bs->change_opaque);
446
    }
447
}
448

    
449
void bdrv_delete(BlockDriverState *bs)
450
{
451
    /* XXX: remove the driver list */
452
    bdrv_close(bs);
453
    qemu_free(bs);
454
}
455

    
456
/* commit COW file into the raw image */
457
int bdrv_commit(BlockDriverState *bs)
458
{
459
    BlockDriver *drv = bs->drv;
460
    int64_t i, total_sectors;
461
    int n, j;
462
    unsigned char sector[512];
463

    
464
    if (!drv)
465
        return -ENOMEDIUM;
466

    
467
    if (bs->read_only) {
468
        return -EACCES;
469
    }
470

    
471
    if (!bs->backing_hd) {
472
        return -ENOTSUP;
473
    }
474

    
475
    total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
476
    for (i = 0; i < total_sectors;) {
477
        if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
478
            for(j = 0; j < n; j++) {
479
                if (bdrv_read(bs, i, sector, 1) != 0) {
480
                    return -EIO;
481
                }
482

    
483
                if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
484
                    return -EIO;
485
                }
486
                i++;
487
            }
488
        } else {
489
            i += n;
490
        }
491
    }
492

    
493
    if (drv->bdrv_make_empty)
494
        return drv->bdrv_make_empty(bs);
495

    
496
    return 0;
497
}
498

    
499
/* return < 0 if error. See bdrv_write() for the return codes */
500
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
501
              uint8_t *buf, int nb_sectors)
502
{
503
    BlockDriver *drv = bs->drv;
504

    
505
    if (!drv)
506
        return -ENOMEDIUM;
507

    
508
    if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
509
            memcpy(buf, bs->boot_sector_data, 512);
510
        sector_num++;
511
        nb_sectors--;
512
        buf += 512;
513
        if (nb_sectors == 0)
514
            return 0;
515
    }
516
    if (drv->bdrv_pread) {
517
        int ret, len;
518
        len = nb_sectors * 512;
519
        ret = drv->bdrv_pread(bs, sector_num * 512, buf, len);
520
        if (ret < 0)
521
            return ret;
522
        else if (ret != len)
523
            return -EINVAL;
524
        else {
525
            bs->rd_bytes += (unsigned) len;
526
            bs->rd_ops ++;
527
            return 0;
528
        }
529
    } else {
530
        return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
531
    }
532
}
533

    
534
/* Return < 0 if error. Important errors are:
535
  -EIO         generic I/O error (may happen for all errors)
536
  -ENOMEDIUM   No media inserted.
537
  -EINVAL      Invalid sector number or nb_sectors
538
  -EACCES      Trying to write a read-only device
539
*/
540
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
541
               const uint8_t *buf, int nb_sectors)
542
{
543
    BlockDriver *drv = bs->drv;
544
    if (!bs->drv)
545
        return -ENOMEDIUM;
546
    if (bs->read_only)
547
        return -EACCES;
548
    if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
549
        memcpy(bs->boot_sector_data, buf, 512);
550
    }
551
    if (drv->bdrv_pwrite) {
552
        int ret, len;
553
        len = nb_sectors * 512;
554
        ret = drv->bdrv_pwrite(bs, sector_num * 512, buf, len);
555
        if (ret < 0)
556
            return ret;
557
        else if (ret != len)
558
            return -EIO;
559
        else {
560
            bs->wr_bytes += (unsigned) len;
561
            bs->wr_ops ++;
562
            return 0;
563
        }
564
    } else {
565
        return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
566
    }
567
}
568

    
569
static int bdrv_pread_em(BlockDriverState *bs, int64_t offset,
570
                         uint8_t *buf, int count1)
571
{
572
    uint8_t tmp_buf[SECTOR_SIZE];
573
    int len, nb_sectors, count;
574
    int64_t sector_num;
575

    
576
    count = count1;
577
    /* first read to align to sector start */
578
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
579
    if (len > count)
580
        len = count;
581
    sector_num = offset >> SECTOR_BITS;
582
    if (len > 0) {
583
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
584
            return -EIO;
585
        memcpy(buf, tmp_buf + (offset & (SECTOR_SIZE - 1)), len);
586
        count -= len;
587
        if (count == 0)
588
            return count1;
589
        sector_num++;
590
        buf += len;
591
    }
592

    
593
    /* read the sectors "in place" */
594
    nb_sectors = count >> SECTOR_BITS;
595
    if (nb_sectors > 0) {
596
        if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0)
597
            return -EIO;
598
        sector_num += nb_sectors;
599
        len = nb_sectors << SECTOR_BITS;
600
        buf += len;
601
        count -= len;
602
    }
603

    
604
    /* add data from the last sector */
605
    if (count > 0) {
606
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
607
            return -EIO;
608
        memcpy(buf, tmp_buf, count);
609
    }
610
    return count1;
611
}
612

    
613
static int bdrv_pwrite_em(BlockDriverState *bs, int64_t offset,
614
                          const uint8_t *buf, int count1)
615
{
616
    uint8_t tmp_buf[SECTOR_SIZE];
617
    int len, nb_sectors, count;
618
    int64_t sector_num;
619

    
620
    count = count1;
621
    /* first write to align to sector start */
622
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
623
    if (len > count)
624
        len = count;
625
    sector_num = offset >> SECTOR_BITS;
626
    if (len > 0) {
627
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
628
            return -EIO;
629
        memcpy(tmp_buf + (offset & (SECTOR_SIZE - 1)), buf, len);
630
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
631
            return -EIO;
632
        count -= len;
633
        if (count == 0)
634
            return count1;
635
        sector_num++;
636
        buf += len;
637
    }
638

    
639
    /* write the sectors "in place" */
640
    nb_sectors = count >> SECTOR_BITS;
641
    if (nb_sectors > 0) {
642
        if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
643
            return -EIO;
644
        sector_num += nb_sectors;
645
        len = nb_sectors << SECTOR_BITS;
646
        buf += len;
647
        count -= len;
648
    }
649

    
650
    /* add data from the last sector */
651
    if (count > 0) {
652
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
653
            return -EIO;
654
        memcpy(tmp_buf, buf, count);
655
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
656
            return -EIO;
657
    }
658
    return count1;
659
}
660

    
661
/**
662
 * Read with byte offsets (needed only for file protocols)
663
 */
664
int bdrv_pread(BlockDriverState *bs, int64_t offset,
665
               void *buf1, int count1)
666
{
667
    BlockDriver *drv = bs->drv;
668

    
669
    if (!drv)
670
        return -ENOMEDIUM;
671
    if (!drv->bdrv_pread)
672
        return bdrv_pread_em(bs, offset, buf1, count1);
673
    return drv->bdrv_pread(bs, offset, buf1, count1);
674
}
675

    
676
/**
677
 * Write with byte offsets (needed only for file protocols)
678
 */
679
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
680
                const void *buf1, int count1)
681
{
682
    BlockDriver *drv = bs->drv;
683

    
684
    if (!drv)
685
        return -ENOMEDIUM;
686
    if (!drv->bdrv_pwrite)
687
        return bdrv_pwrite_em(bs, offset, buf1, count1);
688
    return drv->bdrv_pwrite(bs, offset, buf1, count1);
689
}
690

    
691
/**
692
 * Truncate file to 'offset' bytes (needed only for file protocols)
693
 */
694
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
695
{
696
    BlockDriver *drv = bs->drv;
697
    if (!drv)
698
        return -ENOMEDIUM;
699
    if (!drv->bdrv_truncate)
700
        return -ENOTSUP;
701
    return drv->bdrv_truncate(bs, offset);
702
}
703

    
704
/**
705
 * Length of a file in bytes. Return < 0 if error or unknown.
706
 */
707
int64_t bdrv_getlength(BlockDriverState *bs)
708
{
709
    BlockDriver *drv = bs->drv;
710
    if (!drv)
711
        return -ENOMEDIUM;
712
    if (!drv->bdrv_getlength) {
713
        /* legacy mode */
714
        return bs->total_sectors * SECTOR_SIZE;
715
    }
716
    return drv->bdrv_getlength(bs);
717
}
718

    
719
/* return 0 as number of sectors if no device present or error */
720
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
721
{
722
    int64_t length;
723
    length = bdrv_getlength(bs);
724
    if (length < 0)
725
        length = 0;
726
    else
727
        length = length >> SECTOR_BITS;
728
    *nb_sectors_ptr = length;
729
}
730

    
731
/* force a given boot sector. */
732
void bdrv_set_boot_sector(BlockDriverState *bs, const uint8_t *data, int size)
733
{
734
    bs->boot_sector_enabled = 1;
735
    if (size > 512)
736
        size = 512;
737
    memcpy(bs->boot_sector_data, data, size);
738
    memset(bs->boot_sector_data + size, 0, 512 - size);
739
}
740

    
741
void bdrv_set_geometry_hint(BlockDriverState *bs,
742
                            int cyls, int heads, int secs)
743
{
744
    bs->cyls = cyls;
745
    bs->heads = heads;
746
    bs->secs = secs;
747
}
748

    
749
void bdrv_set_type_hint(BlockDriverState *bs, int type)
750
{
751
    bs->type = type;
752
    bs->removable = ((type == BDRV_TYPE_CDROM ||
753
                      type == BDRV_TYPE_FLOPPY));
754
}
755

    
756
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
757
{
758
    bs->translation = translation;
759
}
760

    
761
void bdrv_get_geometry_hint(BlockDriverState *bs,
762
                            int *pcyls, int *pheads, int *psecs)
763
{
764
    *pcyls = bs->cyls;
765
    *pheads = bs->heads;
766
    *psecs = bs->secs;
767
}
768

    
769
int bdrv_get_type_hint(BlockDriverState *bs)
770
{
771
    return bs->type;
772
}
773

    
774
int bdrv_get_translation_hint(BlockDriverState *bs)
775
{
776
    return bs->translation;
777
}
778

    
779
int bdrv_is_removable(BlockDriverState *bs)
780
{
781
    return bs->removable;
782
}
783

    
784
int bdrv_is_read_only(BlockDriverState *bs)
785
{
786
    return bs->read_only;
787
}
788

    
789
/* XXX: no longer used */
790
void bdrv_set_change_cb(BlockDriverState *bs,
791
                        void (*change_cb)(void *opaque), void *opaque)
792
{
793
    bs->change_cb = change_cb;
794
    bs->change_opaque = opaque;
795
}
796

    
797
int bdrv_is_encrypted(BlockDriverState *bs)
798
{
799
    if (bs->backing_hd && bs->backing_hd->encrypted)
800
        return 1;
801
    return bs->encrypted;
802
}
803

    
804
int bdrv_set_key(BlockDriverState *bs, const char *key)
805
{
806
    int ret;
807
    if (bs->backing_hd && bs->backing_hd->encrypted) {
808
        ret = bdrv_set_key(bs->backing_hd, key);
809
        if (ret < 0)
810
            return ret;
811
        if (!bs->encrypted)
812
            return 0;
813
    }
814
    if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
815
        return -1;
816
    return bs->drv->bdrv_set_key(bs, key);
817
}
818

    
819
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
820
{
821
    if (!bs->drv) {
822
        buf[0] = '\0';
823
    } else {
824
        pstrcpy(buf, buf_size, bs->drv->format_name);
825
    }
826
}
827

    
828
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
829
                         void *opaque)
830
{
831
    BlockDriver *drv;
832

    
833
    for (drv = first_drv; drv != NULL; drv = drv->next) {
834
        it(opaque, drv->format_name);
835
    }
836
}
837

    
838
BlockDriverState *bdrv_find(const char *name)
839
{
840
    BlockDriverState *bs;
841

    
842
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
843
        if (!strcmp(name, bs->device_name))
844
            return bs;
845
    }
846
    return NULL;
847
}
848

    
849
void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque)
850
{
851
    BlockDriverState *bs;
852

    
853
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
854
        it(opaque, bs->device_name);
855
    }
856
}
857

    
858
const char *bdrv_get_device_name(BlockDriverState *bs)
859
{
860
    return bs->device_name;
861
}
862

    
863
void bdrv_flush(BlockDriverState *bs)
864
{
865
    if (bs->drv->bdrv_flush)
866
        bs->drv->bdrv_flush(bs);
867
    if (bs->backing_hd)
868
        bdrv_flush(bs->backing_hd);
869
}
870

    
871
#ifndef QEMU_IMG
872
void bdrv_info(void)
873
{
874
    BlockDriverState *bs;
875

    
876
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
877
        term_printf("%s:", bs->device_name);
878
        term_printf(" type=");
879
        switch(bs->type) {
880
        case BDRV_TYPE_HD:
881
            term_printf("hd");
882
            break;
883
        case BDRV_TYPE_CDROM:
884
            term_printf("cdrom");
885
            break;
886
        case BDRV_TYPE_FLOPPY:
887
            term_printf("floppy");
888
            break;
889
        }
890
        term_printf(" removable=%d", bs->removable);
891
        if (bs->removable) {
892
            term_printf(" locked=%d", bs->locked);
893
        }
894
        if (bs->drv) {
895
            term_printf(" file=");
896
            term_print_filename(bs->filename);
897
            if (bs->backing_file[0] != '\0') {
898
                term_printf(" backing_file=");
899
                term_print_filename(bs->backing_file);
900
            }
901
            term_printf(" ro=%d", bs->read_only);
902
            term_printf(" drv=%s", bs->drv->format_name);
903
            if (bs->encrypted)
904
                term_printf(" encrypted");
905
        } else {
906
            term_printf(" [not inserted]");
907
        }
908
        term_printf("\n");
909
    }
910
}
911

    
912
/* The "info blockstats" command. */
913
void bdrv_info_stats (void)
914
{
915
    BlockDriverState *bs;
916

    
917
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
918
        term_printf ("%s:"
919
                     " rd_bytes=%" PRIu64
920
                     " wr_bytes=%" PRIu64
921
                     " rd_operations=%" PRIu64
922
                     " wr_operations=%" PRIu64
923
                     "\n",
924
                     bs->device_name,
925
                     bs->rd_bytes, bs->wr_bytes,
926
                     bs->rd_ops, bs->wr_ops);
927
    }
928
}
929
#endif
930

    
931
void bdrv_get_backing_filename(BlockDriverState *bs,
932
                               char *filename, int filename_size)
933
{
934
    if (!bs->backing_hd) {
935
        pstrcpy(filename, filename_size, "");
936
    } else {
937
        pstrcpy(filename, filename_size, bs->backing_file);
938
    }
939
}
940

    
941
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
942
                          const uint8_t *buf, int nb_sectors)
943
{
944
    BlockDriver *drv = bs->drv;
945
    if (!drv)
946
        return -ENOMEDIUM;
947
    if (!drv->bdrv_write_compressed)
948
        return -ENOTSUP;
949
    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
950
}
951

    
952
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
953
{
954
    BlockDriver *drv = bs->drv;
955
    if (!drv)
956
        return -ENOMEDIUM;
957
    if (!drv->bdrv_get_info)
958
        return -ENOTSUP;
959
    memset(bdi, 0, sizeof(*bdi));
960
    return drv->bdrv_get_info(bs, bdi);
961
}
962

    
963
/**************************************************************/
964
/* handling of snapshots */
965

    
966
int bdrv_snapshot_create(BlockDriverState *bs,
967
                         QEMUSnapshotInfo *sn_info)
968
{
969
    BlockDriver *drv = bs->drv;
970
    if (!drv)
971
        return -ENOMEDIUM;
972
    if (!drv->bdrv_snapshot_create)
973
        return -ENOTSUP;
974
    return drv->bdrv_snapshot_create(bs, sn_info);
975
}
976

    
977
int bdrv_snapshot_goto(BlockDriverState *bs,
978
                       const char *snapshot_id)
979
{
980
    BlockDriver *drv = bs->drv;
981
    if (!drv)
982
        return -ENOMEDIUM;
983
    if (!drv->bdrv_snapshot_goto)
984
        return -ENOTSUP;
985
    return drv->bdrv_snapshot_goto(bs, snapshot_id);
986
}
987

    
988
int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
989
{
990
    BlockDriver *drv = bs->drv;
991
    if (!drv)
992
        return -ENOMEDIUM;
993
    if (!drv->bdrv_snapshot_delete)
994
        return -ENOTSUP;
995
    return drv->bdrv_snapshot_delete(bs, snapshot_id);
996
}
997

    
998
int bdrv_snapshot_list(BlockDriverState *bs,
999
                       QEMUSnapshotInfo **psn_info)
1000
{
1001
    BlockDriver *drv = bs->drv;
1002
    if (!drv)
1003
        return -ENOMEDIUM;
1004
    if (!drv->bdrv_snapshot_list)
1005
        return -ENOTSUP;
1006
    return drv->bdrv_snapshot_list(bs, psn_info);
1007
}
1008

    
1009
#define NB_SUFFIXES 4
1010

    
1011
char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1012
{
1013
    static const char suffixes[NB_SUFFIXES] = "KMGT";
1014
    int64_t base;
1015
    int i;
1016

    
1017
    if (size <= 999) {
1018
        snprintf(buf, buf_size, "%" PRId64, size);
1019
    } else {
1020
        base = 1024;
1021
        for(i = 0; i < NB_SUFFIXES; i++) {
1022
            if (size < (10 * base)) {
1023
                snprintf(buf, buf_size, "%0.1f%c",
1024
                         (double)size / base,
1025
                         suffixes[i]);
1026
                break;
1027
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1028
                snprintf(buf, buf_size, "%" PRId64 "%c",
1029
                         ((size + (base >> 1)) / base),
1030
                         suffixes[i]);
1031
                break;
1032
            }
1033
            base = base * 1024;
1034
        }
1035
    }
1036
    return buf;
1037
}
1038

    
1039
char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1040
{
1041
    char buf1[128], date_buf[128], clock_buf[128];
1042
#ifdef _WIN32
1043
    struct tm *ptm;
1044
#else
1045
    struct tm tm;
1046
#endif
1047
    time_t ti;
1048
    int64_t secs;
1049

    
1050
    if (!sn) {
1051
        snprintf(buf, buf_size,
1052
                 "%-10s%-20s%7s%20s%15s",
1053
                 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1054
    } else {
1055
        ti = sn->date_sec;
1056
#ifdef _WIN32
1057
        ptm = localtime(&ti);
1058
        strftime(date_buf, sizeof(date_buf),
1059
                 "%Y-%m-%d %H:%M:%S", ptm);
1060
#else
1061
        localtime_r(&ti, &tm);
1062
        strftime(date_buf, sizeof(date_buf),
1063
                 "%Y-%m-%d %H:%M:%S", &tm);
1064
#endif
1065
        secs = sn->vm_clock_nsec / 1000000000;
1066
        snprintf(clock_buf, sizeof(clock_buf),
1067
                 "%02d:%02d:%02d.%03d",
1068
                 (int)(secs / 3600),
1069
                 (int)((secs / 60) % 60),
1070
                 (int)(secs % 60),
1071
                 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1072
        snprintf(buf, buf_size,
1073
                 "%-10s%-20s%7s%20s%15s",
1074
                 sn->id_str, sn->name,
1075
                 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1076
                 date_buf,
1077
                 clock_buf);
1078
    }
1079
    return buf;
1080
}
1081

    
1082

    
1083
/**************************************************************/
1084
/* async I/Os */
1085

    
1086
BlockDriverAIOCB *bdrv_aio_read(BlockDriverState *bs, int64_t sector_num,
1087
                                uint8_t *buf, int nb_sectors,
1088
                                BlockDriverCompletionFunc *cb, void *opaque)
1089
{
1090
    BlockDriver *drv = bs->drv;
1091
    BlockDriverAIOCB *ret;
1092

    
1093
    if (!drv)
1094
        return NULL;
1095

    
1096
    /* XXX: we assume that nb_sectors == 0 is suppored by the async read */
1097
    if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
1098
        memcpy(buf, bs->boot_sector_data, 512);
1099
        sector_num++;
1100
        nb_sectors--;
1101
        buf += 512;
1102
    }
1103

    
1104
    ret = drv->bdrv_aio_read(bs, sector_num, buf, nb_sectors, cb, opaque);
1105

    
1106
    if (ret) {
1107
        /* Update stats even though technically transfer has not happened. */
1108
        bs->rd_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1109
        bs->rd_ops ++;
1110
    }
1111

    
1112
    return ret;
1113
}
1114

    
1115
BlockDriverAIOCB *bdrv_aio_write(BlockDriverState *bs, int64_t sector_num,
1116
                                 const uint8_t *buf, int nb_sectors,
1117
                                 BlockDriverCompletionFunc *cb, void *opaque)
1118
{
1119
    BlockDriver *drv = bs->drv;
1120
    BlockDriverAIOCB *ret;
1121

    
1122
    if (!drv)
1123
        return NULL;
1124
    if (bs->read_only)
1125
        return NULL;
1126
    if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
1127
        memcpy(bs->boot_sector_data, buf, 512);
1128
    }
1129

    
1130
    ret = drv->bdrv_aio_write(bs, sector_num, buf, nb_sectors, cb, opaque);
1131

    
1132
    if (ret) {
1133
        /* Update stats even though technically transfer has not happened. */
1134
        bs->wr_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1135
        bs->wr_ops ++;
1136
    }
1137

    
1138
    return ret;
1139
}
1140

    
1141
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1142
{
1143
    BlockDriver *drv = acb->bs->drv;
1144

    
1145
    drv->bdrv_aio_cancel(acb);
1146
}
1147

    
1148

    
1149
/**************************************************************/
1150
/* async block device emulation */
1151

    
1152
#ifdef QEMU_IMG
1153
static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
1154
        int64_t sector_num, uint8_t *buf, int nb_sectors,
1155
        BlockDriverCompletionFunc *cb, void *opaque)
1156
{
1157
    int ret;
1158
    ret = bdrv_read(bs, sector_num, buf, nb_sectors);
1159
    cb(opaque, ret);
1160
    return NULL;
1161
}
1162

    
1163
static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
1164
        int64_t sector_num, const uint8_t *buf, int nb_sectors,
1165
        BlockDriverCompletionFunc *cb, void *opaque)
1166
{
1167
    int ret;
1168
    ret = bdrv_write(bs, sector_num, buf, nb_sectors);
1169
    cb(opaque, ret);
1170
    return NULL;
1171
}
1172

    
1173
static void bdrv_aio_cancel_em(BlockDriverAIOCB *acb)
1174
{
1175
}
1176
#else
1177
static void bdrv_aio_bh_cb(void *opaque)
1178
{
1179
    BlockDriverAIOCBSync *acb = opaque;
1180
    acb->common.cb(acb->common.opaque, acb->ret);
1181
    qemu_aio_release(acb);
1182
}
1183

    
1184
static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
1185
        int64_t sector_num, uint8_t *buf, int nb_sectors,
1186
        BlockDriverCompletionFunc *cb, void *opaque)
1187
{
1188
    BlockDriverAIOCBSync *acb;
1189
    int ret;
1190

    
1191
    acb = qemu_aio_get(bs, cb, opaque);
1192
    if (!acb->bh)
1193
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1194
    ret = bdrv_read(bs, sector_num, buf, nb_sectors);
1195
    acb->ret = ret;
1196
    qemu_bh_schedule(acb->bh);
1197
    return &acb->common;
1198
}
1199

    
1200
static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
1201
        int64_t sector_num, const uint8_t *buf, int nb_sectors,
1202
        BlockDriverCompletionFunc *cb, void *opaque)
1203
{
1204
    BlockDriverAIOCBSync *acb;
1205
    int ret;
1206

    
1207
    acb = qemu_aio_get(bs, cb, opaque);
1208
    if (!acb->bh)
1209
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1210
    ret = bdrv_write(bs, sector_num, buf, nb_sectors);
1211
    acb->ret = ret;
1212
    qemu_bh_schedule(acb->bh);
1213
    return &acb->common;
1214
}
1215

    
1216
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1217
{
1218
    BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1219
    qemu_bh_cancel(acb->bh);
1220
    qemu_aio_release(acb);
1221
}
1222
#endif /* !QEMU_IMG */
1223

    
1224
/**************************************************************/
1225
/* sync block device emulation */
1226

    
1227
static void bdrv_rw_em_cb(void *opaque, int ret)
1228
{
1229
    *(int *)opaque = ret;
1230
}
1231

    
1232
#define NOT_DONE 0x7fffffff
1233

    
1234
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1235
                        uint8_t *buf, int nb_sectors)
1236
{
1237
    int async_ret;
1238
    BlockDriverAIOCB *acb;
1239

    
1240
    async_ret = NOT_DONE;
1241
    qemu_aio_wait_start();
1242
    acb = bdrv_aio_read(bs, sector_num, buf, nb_sectors,
1243
                        bdrv_rw_em_cb, &async_ret);
1244
    if (acb == NULL) {
1245
        qemu_aio_wait_end();
1246
        return -1;
1247
    }
1248
    while (async_ret == NOT_DONE) {
1249
        qemu_aio_wait();
1250
    }
1251
    qemu_aio_wait_end();
1252
    return async_ret;
1253
}
1254

    
1255
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1256
                         const uint8_t *buf, int nb_sectors)
1257
{
1258
    int async_ret;
1259
    BlockDriverAIOCB *acb;
1260

    
1261
    async_ret = NOT_DONE;
1262
    qemu_aio_wait_start();
1263
    acb = bdrv_aio_write(bs, sector_num, buf, nb_sectors,
1264
                         bdrv_rw_em_cb, &async_ret);
1265
    if (acb == NULL) {
1266
        qemu_aio_wait_end();
1267
        return -1;
1268
    }
1269
    while (async_ret == NOT_DONE) {
1270
        qemu_aio_wait();
1271
    }
1272
    qemu_aio_wait_end();
1273
    return async_ret;
1274
}
1275

    
1276
void bdrv_init(void)
1277
{
1278
    bdrv_register(&bdrv_raw);
1279
    bdrv_register(&bdrv_host_device);
1280
#ifndef _WIN32
1281
    bdrv_register(&bdrv_cow);
1282
#endif
1283
    bdrv_register(&bdrv_qcow);
1284
    bdrv_register(&bdrv_vmdk);
1285
    bdrv_register(&bdrv_cloop);
1286
    bdrv_register(&bdrv_dmg);
1287
    bdrv_register(&bdrv_bochs);
1288
    bdrv_register(&bdrv_vpc);
1289
    bdrv_register(&bdrv_vvfat);
1290
    bdrv_register(&bdrv_qcow2);
1291
    bdrv_register(&bdrv_parallels);
1292
}
1293

    
1294
void *qemu_aio_get(BlockDriverState *bs, BlockDriverCompletionFunc *cb,
1295
                   void *opaque)
1296
{
1297
    BlockDriver *drv;
1298
    BlockDriverAIOCB *acb;
1299

    
1300
    drv = bs->drv;
1301
    if (drv->free_aiocb) {
1302
        acb = drv->free_aiocb;
1303
        drv->free_aiocb = acb->next;
1304
    } else {
1305
        acb = qemu_mallocz(drv->aiocb_size);
1306
        if (!acb)
1307
            return NULL;
1308
    }
1309
    acb->bs = bs;
1310
    acb->cb = cb;
1311
    acb->opaque = opaque;
1312
    return acb;
1313
}
1314

    
1315
void qemu_aio_release(void *p)
1316
{
1317
    BlockDriverAIOCB *acb = p;
1318
    BlockDriver *drv = acb->bs->drv;
1319
    acb->next = drv->free_aiocb;
1320
    drv->free_aiocb = acb;
1321
}
1322

    
1323
/**************************************************************/
1324
/* removable device support */
1325

    
1326
/**
1327
 * Return TRUE if the media is present
1328
 */
1329
int bdrv_is_inserted(BlockDriverState *bs)
1330
{
1331
    BlockDriver *drv = bs->drv;
1332
    int ret;
1333
    if (!drv)
1334
        return 0;
1335
    if (!drv->bdrv_is_inserted)
1336
        return 1;
1337
    ret = drv->bdrv_is_inserted(bs);
1338
    return ret;
1339
}
1340

    
1341
/**
1342
 * Return TRUE if the media changed since the last call to this
1343
 * function. It is currently only used for floppy disks
1344
 */
1345
int bdrv_media_changed(BlockDriverState *bs)
1346
{
1347
    BlockDriver *drv = bs->drv;
1348
    int ret;
1349

    
1350
    if (!drv || !drv->bdrv_media_changed)
1351
        ret = -ENOTSUP;
1352
    else
1353
        ret = drv->bdrv_media_changed(bs);
1354
    if (ret == -ENOTSUP)
1355
        ret = bs->media_changed;
1356
    bs->media_changed = 0;
1357
    return ret;
1358
}
1359

    
1360
/**
1361
 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
1362
 */
1363
void bdrv_eject(BlockDriverState *bs, int eject_flag)
1364
{
1365
    BlockDriver *drv = bs->drv;
1366
    int ret;
1367

    
1368
    if (!drv || !drv->bdrv_eject) {
1369
        ret = -ENOTSUP;
1370
    } else {
1371
        ret = drv->bdrv_eject(bs, eject_flag);
1372
    }
1373
    if (ret == -ENOTSUP) {
1374
        if (eject_flag)
1375
            bdrv_close(bs);
1376
    }
1377
}
1378

    
1379
int bdrv_is_locked(BlockDriverState *bs)
1380
{
1381
    return bs->locked;
1382
}
1383

    
1384
/**
1385
 * Lock or unlock the media (if it is locked, the user won't be able
1386
 * to eject it manually).
1387
 */
1388
void bdrv_set_locked(BlockDriverState *bs, int locked)
1389
{
1390
    BlockDriver *drv = bs->drv;
1391

    
1392
    bs->locked = locked;
1393
    if (drv && drv->bdrv_set_locked) {
1394
        drv->bdrv_set_locked(bs, locked);
1395
    }
1396
}