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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, count = 0;
569
        len = nb_sectors * 512;
570
        do {
571
            ret = drv->bdrv_pwrite(bs, sector_num * 512, buf, len - count);
572
            if (ret < 0) {
573
                printf("bdrv_write ret=%d\n", ret);
574
                return ret;
575
            }
576
            count += ret;
577
            buf += ret;
578
        } while (count != len);
579
        bs->wr_bytes += (unsigned) len;
580
        bs->wr_ops ++;
581
        return 0;
582
    }
583
    return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
584
}
585

    
586
static int bdrv_pread_em(BlockDriverState *bs, int64_t offset,
587
                         uint8_t *buf, int count1)
588
{
589
    uint8_t tmp_buf[SECTOR_SIZE];
590
    int len, nb_sectors, count;
591
    int64_t sector_num;
592

    
593
    count = count1;
594
    /* first read to align to sector start */
595
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
596
    if (len > count)
597
        len = count;
598
    sector_num = offset >> SECTOR_BITS;
599
    if (len > 0) {
600
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
601
            return -EIO;
602
        memcpy(buf, tmp_buf + (offset & (SECTOR_SIZE - 1)), len);
603
        count -= len;
604
        if (count == 0)
605
            return count1;
606
        sector_num++;
607
        buf += len;
608
    }
609

    
610
    /* read the sectors "in place" */
611
    nb_sectors = count >> SECTOR_BITS;
612
    if (nb_sectors > 0) {
613
        if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0)
614
            return -EIO;
615
        sector_num += nb_sectors;
616
        len = nb_sectors << SECTOR_BITS;
617
        buf += len;
618
        count -= len;
619
    }
620

    
621
    /* add data from the last sector */
622
    if (count > 0) {
623
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
624
            return -EIO;
625
        memcpy(buf, tmp_buf, count);
626
    }
627
    return count1;
628
}
629

    
630
static int bdrv_pwrite_em(BlockDriverState *bs, int64_t offset,
631
                          const uint8_t *buf, int count1)
632
{
633
    uint8_t tmp_buf[SECTOR_SIZE];
634
    int len, nb_sectors, count;
635
    int64_t sector_num;
636

    
637
    count = count1;
638
    /* first write to align to sector start */
639
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
640
    if (len > count)
641
        len = count;
642
    sector_num = offset >> SECTOR_BITS;
643
    if (len > 0) {
644
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
645
            return -EIO;
646
        memcpy(tmp_buf + (offset & (SECTOR_SIZE - 1)), buf, len);
647
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
648
            return -EIO;
649
        count -= len;
650
        if (count == 0)
651
            return count1;
652
        sector_num++;
653
        buf += len;
654
    }
655

    
656
    /* write the sectors "in place" */
657
    nb_sectors = count >> SECTOR_BITS;
658
    if (nb_sectors > 0) {
659
        if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
660
            return -EIO;
661
        sector_num += nb_sectors;
662
        len = nb_sectors << SECTOR_BITS;
663
        buf += len;
664
        count -= len;
665
    }
666

    
667
    /* add data from the last sector */
668
    if (count > 0) {
669
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
670
            return -EIO;
671
        memcpy(tmp_buf, buf, count);
672
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
673
            return -EIO;
674
    }
675
    return count1;
676
}
677

    
678
/**
679
 * Read with byte offsets (needed only for file protocols)
680
 */
681
int bdrv_pread(BlockDriverState *bs, int64_t offset,
682
               void *buf1, int count1)
683
{
684
    BlockDriver *drv = bs->drv;
685

    
686
    if (!drv)
687
        return -ENOMEDIUM;
688
    if (!drv->bdrv_pread)
689
        return bdrv_pread_em(bs, offset, buf1, count1);
690
    return drv->bdrv_pread(bs, offset, buf1, count1);
691
}
692

    
693
/**
694
 * Write with byte offsets (needed only for file protocols)
695
 */
696
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
697
                const void *buf1, int count1)
698
{
699
    BlockDriver *drv = bs->drv;
700

    
701
    if (!drv)
702
        return -ENOMEDIUM;
703
    if (!drv->bdrv_pwrite)
704
        return bdrv_pwrite_em(bs, offset, buf1, count1);
705
    return drv->bdrv_pwrite(bs, offset, buf1, count1);
706
}
707

    
708
/**
709
 * Truncate file to 'offset' bytes (needed only for file protocols)
710
 */
711
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
712
{
713
    BlockDriver *drv = bs->drv;
714
    if (!drv)
715
        return -ENOMEDIUM;
716
    if (!drv->bdrv_truncate)
717
        return -ENOTSUP;
718
    return drv->bdrv_truncate(bs, offset);
719
}
720

    
721
/**
722
 * Length of a file in bytes. Return < 0 if error or unknown.
723
 */
724
int64_t bdrv_getlength(BlockDriverState *bs)
725
{
726
    BlockDriver *drv = bs->drv;
727
    if (!drv)
728
        return -ENOMEDIUM;
729
    if (!drv->bdrv_getlength) {
730
        /* legacy mode */
731
        return bs->total_sectors * SECTOR_SIZE;
732
    }
733
    return drv->bdrv_getlength(bs);
734
}
735

    
736
/* return 0 as number of sectors if no device present or error */
737
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
738
{
739
    int64_t length;
740
    length = bdrv_getlength(bs);
741
    if (length < 0)
742
        length = 0;
743
    else
744
        length = length >> SECTOR_BITS;
745
    *nb_sectors_ptr = length;
746
}
747

    
748
struct partition {
749
        uint8_t boot_ind;           /* 0x80 - active */
750
        uint8_t head;               /* starting head */
751
        uint8_t sector;             /* starting sector */
752
        uint8_t cyl;                /* starting cylinder */
753
        uint8_t sys_ind;            /* What partition type */
754
        uint8_t end_head;           /* end head */
755
        uint8_t end_sector;         /* end sector */
756
        uint8_t end_cyl;            /* end cylinder */
757
        uint32_t start_sect;        /* starting sector counting from 0 */
758
        uint32_t nr_sects;          /* nr of sectors in partition */
759
} __attribute__((packed));
760

    
761
/* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
762
static int guess_disk_lchs(BlockDriverState *bs,
763
                           int *pcylinders, int *pheads, int *psectors)
764
{
765
    uint8_t buf[512];
766
    int ret, i, heads, sectors, cylinders;
767
    struct partition *p;
768
    uint32_t nr_sects;
769
    uint64_t nb_sectors;
770

    
771
    bdrv_get_geometry(bs, &nb_sectors);
772

    
773
    ret = bdrv_read(bs, 0, buf, 1);
774
    if (ret < 0)
775
        return -1;
776
    /* test msdos magic */
777
    if (buf[510] != 0x55 || buf[511] != 0xaa)
778
        return -1;
779
    for(i = 0; i < 4; i++) {
780
        p = ((struct partition *)(buf + 0x1be)) + i;
781
        nr_sects = le32_to_cpu(p->nr_sects);
782
        if (nr_sects && p->end_head) {
783
            /* We make the assumption that the partition terminates on
784
               a cylinder boundary */
785
            heads = p->end_head + 1;
786
            sectors = p->end_sector & 63;
787
            if (sectors == 0)
788
                continue;
789
            cylinders = nb_sectors / (heads * sectors);
790
            if (cylinders < 1 || cylinders > 16383)
791
                continue;
792
            *pheads = heads;
793
            *psectors = sectors;
794
            *pcylinders = cylinders;
795
#if 0
796
            printf("guessed geometry: LCHS=%d %d %d\n",
797
                   cylinders, heads, sectors);
798
#endif
799
            return 0;
800
        }
801
    }
802
    return -1;
803
}
804

    
805
void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
806
{
807
    int translation, lba_detected = 0;
808
    int cylinders, heads, secs;
809
    uint64_t nb_sectors;
810

    
811
    /* if a geometry hint is available, use it */
812
    bdrv_get_geometry(bs, &nb_sectors);
813
    bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
814
    translation = bdrv_get_translation_hint(bs);
815
    if (cylinders != 0) {
816
        *pcyls = cylinders;
817
        *pheads = heads;
818
        *psecs = secs;
819
    } else {
820
        if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
821
            if (heads > 16) {
822
                /* if heads > 16, it means that a BIOS LBA
823
                   translation was active, so the default
824
                   hardware geometry is OK */
825
                lba_detected = 1;
826
                goto default_geometry;
827
            } else {
828
                *pcyls = cylinders;
829
                *pheads = heads;
830
                *psecs = secs;
831
                /* disable any translation to be in sync with
832
                   the logical geometry */
833
                if (translation == BIOS_ATA_TRANSLATION_AUTO) {
834
                    bdrv_set_translation_hint(bs,
835
                                              BIOS_ATA_TRANSLATION_NONE);
836
                }
837
            }
838
        } else {
839
        default_geometry:
840
            /* if no geometry, use a standard physical disk geometry */
841
            cylinders = nb_sectors / (16 * 63);
842

    
843
            if (cylinders > 16383)
844
                cylinders = 16383;
845
            else if (cylinders < 2)
846
                cylinders = 2;
847
            *pcyls = cylinders;
848
            *pheads = 16;
849
            *psecs = 63;
850
            if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
851
                if ((*pcyls * *pheads) <= 131072) {
852
                    bdrv_set_translation_hint(bs,
853
                                              BIOS_ATA_TRANSLATION_LARGE);
854
                } else {
855
                    bdrv_set_translation_hint(bs,
856
                                              BIOS_ATA_TRANSLATION_LBA);
857
                }
858
            }
859
        }
860
        bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
861
    }
862
}
863

    
864
void bdrv_set_geometry_hint(BlockDriverState *bs,
865
                            int cyls, int heads, int secs)
866
{
867
    bs->cyls = cyls;
868
    bs->heads = heads;
869
    bs->secs = secs;
870
}
871

    
872
void bdrv_set_type_hint(BlockDriverState *bs, int type)
873
{
874
    bs->type = type;
875
    bs->removable = ((type == BDRV_TYPE_CDROM ||
876
                      type == BDRV_TYPE_FLOPPY));
877
}
878

    
879
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
880
{
881
    bs->translation = translation;
882
}
883

    
884
void bdrv_get_geometry_hint(BlockDriverState *bs,
885
                            int *pcyls, int *pheads, int *psecs)
886
{
887
    *pcyls = bs->cyls;
888
    *pheads = bs->heads;
889
    *psecs = bs->secs;
890
}
891

    
892
int bdrv_get_type_hint(BlockDriverState *bs)
893
{
894
    return bs->type;
895
}
896

    
897
int bdrv_get_translation_hint(BlockDriverState *bs)
898
{
899
    return bs->translation;
900
}
901

    
902
int bdrv_is_removable(BlockDriverState *bs)
903
{
904
    return bs->removable;
905
}
906

    
907
int bdrv_is_read_only(BlockDriverState *bs)
908
{
909
    return bs->read_only;
910
}
911

    
912
int bdrv_is_sg(BlockDriverState *bs)
913
{
914
    return bs->sg;
915
}
916

    
917
/* XXX: no longer used */
918
void bdrv_set_change_cb(BlockDriverState *bs,
919
                        void (*change_cb)(void *opaque), void *opaque)
920
{
921
    bs->change_cb = change_cb;
922
    bs->change_opaque = opaque;
923
}
924

    
925
int bdrv_is_encrypted(BlockDriverState *bs)
926
{
927
    if (bs->backing_hd && bs->backing_hd->encrypted)
928
        return 1;
929
    return bs->encrypted;
930
}
931

    
932
int bdrv_set_key(BlockDriverState *bs, const char *key)
933
{
934
    int ret;
935
    if (bs->backing_hd && bs->backing_hd->encrypted) {
936
        ret = bdrv_set_key(bs->backing_hd, key);
937
        if (ret < 0)
938
            return ret;
939
        if (!bs->encrypted)
940
            return 0;
941
    }
942
    if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
943
        return -1;
944
    return bs->drv->bdrv_set_key(bs, key);
945
}
946

    
947
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
948
{
949
    if (!bs->drv) {
950
        buf[0] = '\0';
951
    } else {
952
        pstrcpy(buf, buf_size, bs->drv->format_name);
953
    }
954
}
955

    
956
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
957
                         void *opaque)
958
{
959
    BlockDriver *drv;
960

    
961
    for (drv = first_drv; drv != NULL; drv = drv->next) {
962
        it(opaque, drv->format_name);
963
    }
964
}
965

    
966
BlockDriverState *bdrv_find(const char *name)
967
{
968
    BlockDriverState *bs;
969

    
970
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
971
        if (!strcmp(name, bs->device_name))
972
            return bs;
973
    }
974
    return NULL;
975
}
976

    
977
void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque)
978
{
979
    BlockDriverState *bs;
980

    
981
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
982
        it(opaque, bs->device_name);
983
    }
984
}
985

    
986
const char *bdrv_get_device_name(BlockDriverState *bs)
987
{
988
    return bs->device_name;
989
}
990

    
991
void bdrv_flush(BlockDriverState *bs)
992
{
993
    if (bs->drv->bdrv_flush)
994
        bs->drv->bdrv_flush(bs);
995
    if (bs->backing_hd)
996
        bdrv_flush(bs->backing_hd);
997
}
998

    
999
void bdrv_flush_all(void)
1000
{
1001
    BlockDriverState *bs;
1002

    
1003
    for (bs = bdrv_first; bs != NULL; bs = bs->next)
1004
        if (bs->drv && !bdrv_is_read_only(bs) && 
1005
            (!bdrv_is_removable(bs) || bdrv_is_inserted(bs)))
1006
            bdrv_flush(bs);
1007
}
1008

    
1009
/*
1010
 * Returns true iff the specified sector is present in the disk image. Drivers
1011
 * not implementing the functionality are assumed to not support backing files,
1012
 * hence all their sectors are reported as allocated.
1013
 *
1014
 * 'pnum' is set to the number of sectors (including and immediately following
1015
 * the specified sector) that are known to be in the same
1016
 * allocated/unallocated state.
1017
 *
1018
 * 'nb_sectors' is the max value 'pnum' should be set to.
1019
 */
1020
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
1021
        int *pnum)
1022
{
1023
    int64_t n;
1024
    if (!bs->drv->bdrv_is_allocated) {
1025
        if (sector_num >= bs->total_sectors) {
1026
            *pnum = 0;
1027
            return 0;
1028
        }
1029
        n = bs->total_sectors - sector_num;
1030
        *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
1031
        return 1;
1032
    }
1033
    return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
1034
}
1035

    
1036
void bdrv_info(void)
1037
{
1038
    BlockDriverState *bs;
1039

    
1040
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1041
        term_printf("%s:", bs->device_name);
1042
        term_printf(" type=");
1043
        switch(bs->type) {
1044
        case BDRV_TYPE_HD:
1045
            term_printf("hd");
1046
            break;
1047
        case BDRV_TYPE_CDROM:
1048
            term_printf("cdrom");
1049
            break;
1050
        case BDRV_TYPE_FLOPPY:
1051
            term_printf("floppy");
1052
            break;
1053
        }
1054
        term_printf(" removable=%d", bs->removable);
1055
        if (bs->removable) {
1056
            term_printf(" locked=%d", bs->locked);
1057
        }
1058
        if (bs->drv) {
1059
            term_printf(" file=");
1060
            term_print_filename(bs->filename);
1061
            if (bs->backing_file[0] != '\0') {
1062
                term_printf(" backing_file=");
1063
                term_print_filename(bs->backing_file);
1064
            }
1065
            term_printf(" ro=%d", bs->read_only);
1066
            term_printf(" drv=%s", bs->drv->format_name);
1067
            if (bs->encrypted)
1068
                term_printf(" encrypted");
1069
        } else {
1070
            term_printf(" [not inserted]");
1071
        }
1072
        term_printf("\n");
1073
    }
1074
}
1075

    
1076
/* The "info blockstats" command. */
1077
void bdrv_info_stats (void)
1078
{
1079
    BlockDriverState *bs;
1080
    BlockDriverInfo bdi;
1081

    
1082
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1083
        term_printf ("%s:"
1084
                     " rd_bytes=%" PRIu64
1085
                     " wr_bytes=%" PRIu64
1086
                     " rd_operations=%" PRIu64
1087
                     " wr_operations=%" PRIu64
1088
                     ,
1089
                     bs->device_name,
1090
                     bs->rd_bytes, bs->wr_bytes,
1091
                     bs->rd_ops, bs->wr_ops);
1092
        if (bdrv_get_info(bs, &bdi) == 0)
1093
            term_printf(" high=%" PRIu64,
1094
                        bdi.highest_alloc);
1095
        term_printf("\n");
1096
    }
1097
}
1098

    
1099
void bdrv_get_backing_filename(BlockDriverState *bs,
1100
                               char *filename, int filename_size)
1101
{
1102
    if (!bs->backing_hd) {
1103
        pstrcpy(filename, filename_size, "");
1104
    } else {
1105
        pstrcpy(filename, filename_size, bs->backing_file);
1106
    }
1107
}
1108

    
1109
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
1110
                          const uint8_t *buf, int nb_sectors)
1111
{
1112
    BlockDriver *drv = bs->drv;
1113
    if (!drv)
1114
        return -ENOMEDIUM;
1115
    if (!drv->bdrv_write_compressed)
1116
        return -ENOTSUP;
1117
    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
1118
}
1119

    
1120
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1121
{
1122
    BlockDriver *drv = bs->drv;
1123
    if (!drv)
1124
        return -ENOMEDIUM;
1125
    if (!drv->bdrv_get_info)
1126
        return -ENOTSUP;
1127
    memset(bdi, 0, sizeof(*bdi));
1128
    return drv->bdrv_get_info(bs, bdi);
1129
}
1130

    
1131
/**************************************************************/
1132
/* handling of snapshots */
1133

    
1134
int bdrv_snapshot_create(BlockDriverState *bs,
1135
                         QEMUSnapshotInfo *sn_info)
1136
{
1137
    BlockDriver *drv = bs->drv;
1138
    if (!drv)
1139
        return -ENOMEDIUM;
1140
    if (!drv->bdrv_snapshot_create)
1141
        return -ENOTSUP;
1142
    return drv->bdrv_snapshot_create(bs, sn_info);
1143
}
1144

    
1145
int bdrv_snapshot_goto(BlockDriverState *bs,
1146
                       const char *snapshot_id)
1147
{
1148
    BlockDriver *drv = bs->drv;
1149
    if (!drv)
1150
        return -ENOMEDIUM;
1151
    if (!drv->bdrv_snapshot_goto)
1152
        return -ENOTSUP;
1153
    return drv->bdrv_snapshot_goto(bs, snapshot_id);
1154
}
1155

    
1156
int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
1157
{
1158
    BlockDriver *drv = bs->drv;
1159
    if (!drv)
1160
        return -ENOMEDIUM;
1161
    if (!drv->bdrv_snapshot_delete)
1162
        return -ENOTSUP;
1163
    return drv->bdrv_snapshot_delete(bs, snapshot_id);
1164
}
1165

    
1166
int bdrv_snapshot_list(BlockDriverState *bs,
1167
                       QEMUSnapshotInfo **psn_info)
1168
{
1169
    BlockDriver *drv = bs->drv;
1170
    if (!drv)
1171
        return -ENOMEDIUM;
1172
    if (!drv->bdrv_snapshot_list)
1173
        return -ENOTSUP;
1174
    return drv->bdrv_snapshot_list(bs, psn_info);
1175
}
1176

    
1177
#define NB_SUFFIXES 4
1178

    
1179
char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1180
{
1181
    static const char suffixes[NB_SUFFIXES] = "KMGT";
1182
    int64_t base;
1183
    int i;
1184

    
1185
    if (size <= 999) {
1186
        snprintf(buf, buf_size, "%" PRId64, size);
1187
    } else {
1188
        base = 1024;
1189
        for(i = 0; i < NB_SUFFIXES; i++) {
1190
            if (size < (10 * base)) {
1191
                snprintf(buf, buf_size, "%0.1f%c",
1192
                         (double)size / base,
1193
                         suffixes[i]);
1194
                break;
1195
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1196
                snprintf(buf, buf_size, "%" PRId64 "%c",
1197
                         ((size + (base >> 1)) / base),
1198
                         suffixes[i]);
1199
                break;
1200
            }
1201
            base = base * 1024;
1202
        }
1203
    }
1204
    return buf;
1205
}
1206

    
1207
char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1208
{
1209
    char buf1[128], date_buf[128], clock_buf[128];
1210
#ifdef _WIN32
1211
    struct tm *ptm;
1212
#else
1213
    struct tm tm;
1214
#endif
1215
    time_t ti;
1216
    int64_t secs;
1217

    
1218
    if (!sn) {
1219
        snprintf(buf, buf_size,
1220
                 "%-10s%-20s%7s%20s%15s",
1221
                 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1222
    } else {
1223
        ti = sn->date_sec;
1224
#ifdef _WIN32
1225
        ptm = localtime(&ti);
1226
        strftime(date_buf, sizeof(date_buf),
1227
                 "%Y-%m-%d %H:%M:%S", ptm);
1228
#else
1229
        localtime_r(&ti, &tm);
1230
        strftime(date_buf, sizeof(date_buf),
1231
                 "%Y-%m-%d %H:%M:%S", &tm);
1232
#endif
1233
        secs = sn->vm_clock_nsec / 1000000000;
1234
        snprintf(clock_buf, sizeof(clock_buf),
1235
                 "%02d:%02d:%02d.%03d",
1236
                 (int)(secs / 3600),
1237
                 (int)((secs / 60) % 60),
1238
                 (int)(secs % 60),
1239
                 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1240
        snprintf(buf, buf_size,
1241
                 "%-10s%-20s%7s%20s%15s",
1242
                 sn->id_str, sn->name,
1243
                 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1244
                 date_buf,
1245
                 clock_buf);
1246
    }
1247
    return buf;
1248
}
1249

    
1250

    
1251
/**************************************************************/
1252
/* async I/Os */
1253

    
1254
typedef struct VectorTranslationState {
1255
    QEMUIOVector *iov;
1256
    uint8_t *bounce;
1257
    int is_write;
1258
    BlockDriverAIOCB *aiocb;
1259
    BlockDriverAIOCB *this_aiocb;
1260
} VectorTranslationState;
1261

    
1262
static void bdrv_aio_rw_vector_cb(void *opaque, int ret)
1263
{
1264
    VectorTranslationState *s = opaque;
1265

    
1266
    if (!s->is_write) {
1267
        qemu_iovec_from_buffer(s->iov, s->bounce);
1268
    }
1269
    qemu_free(s->bounce);
1270
    s->this_aiocb->cb(s->this_aiocb->opaque, ret);
1271
    qemu_aio_release(s->this_aiocb);
1272
}
1273

    
1274
static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
1275
                                            int64_t sector_num,
1276
                                            QEMUIOVector *iov,
1277
                                            int nb_sectors,
1278
                                            BlockDriverCompletionFunc *cb,
1279
                                            void *opaque,
1280
                                            int is_write)
1281

    
1282
{
1283
    VectorTranslationState *s = qemu_mallocz(sizeof(*s));
1284
    BlockDriverAIOCB *aiocb = qemu_aio_get(bs, cb, opaque);
1285

    
1286
    s->this_aiocb = aiocb;
1287
    s->iov = iov;
1288
    s->bounce = qemu_memalign(512, nb_sectors * 512);
1289
    s->is_write = is_write;
1290
    if (is_write) {
1291
        qemu_iovec_to_buffer(s->iov, s->bounce);
1292
        s->aiocb = bdrv_aio_write(bs, sector_num, s->bounce, nb_sectors,
1293
                                  bdrv_aio_rw_vector_cb, s);
1294
    } else {
1295
        s->aiocb = bdrv_aio_read(bs, sector_num, s->bounce, nb_sectors,
1296
                                 bdrv_aio_rw_vector_cb, s);
1297
    }
1298
    return aiocb;
1299
}
1300

    
1301
BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
1302
                                 QEMUIOVector *iov, int nb_sectors,
1303
                                 BlockDriverCompletionFunc *cb, void *opaque)
1304
{
1305
    return bdrv_aio_rw_vector(bs, sector_num, iov, nb_sectors,
1306
                              cb, opaque, 0);
1307
}
1308

    
1309
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
1310
                                  QEMUIOVector *iov, int nb_sectors,
1311
                                  BlockDriverCompletionFunc *cb, void *opaque)
1312
{
1313
    return bdrv_aio_rw_vector(bs, sector_num, iov, nb_sectors,
1314
                              cb, opaque, 1);
1315
}
1316

    
1317
BlockDriverAIOCB *bdrv_aio_read(BlockDriverState *bs, int64_t sector_num,
1318
                                uint8_t *buf, int nb_sectors,
1319
                                BlockDriverCompletionFunc *cb, void *opaque)
1320
{
1321
    BlockDriver *drv = bs->drv;
1322
    BlockDriverAIOCB *ret;
1323

    
1324
    if (!drv)
1325
        return NULL;
1326

    
1327
    ret = drv->bdrv_aio_read(bs, sector_num, buf, nb_sectors, cb, opaque);
1328

    
1329
    if (ret) {
1330
        /* Update stats even though technically transfer has not happened. */
1331
        bs->rd_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1332
        bs->rd_ops ++;
1333
    }
1334

    
1335
    return ret;
1336
}
1337

    
1338
BlockDriverAIOCB *bdrv_aio_write(BlockDriverState *bs, int64_t sector_num,
1339
                                 const uint8_t *buf, int nb_sectors,
1340
                                 BlockDriverCompletionFunc *cb, void *opaque)
1341
{
1342
    BlockDriver *drv = bs->drv;
1343
    BlockDriverAIOCB *ret;
1344

    
1345
    if (!drv)
1346
        return NULL;
1347
    if (bs->read_only)
1348
        return NULL;
1349

    
1350
    ret = drv->bdrv_aio_write(bs, sector_num, buf, nb_sectors, cb, opaque);
1351

    
1352
    if (ret) {
1353
        /* Update stats even though technically transfer has not happened. */
1354
        bs->wr_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1355
        bs->wr_ops ++;
1356
    }
1357

    
1358
    return ret;
1359
}
1360

    
1361
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1362
{
1363
    BlockDriver *drv = acb->bs->drv;
1364

    
1365
    if (acb->cb == bdrv_aio_rw_vector_cb) {
1366
        VectorTranslationState *s = acb->opaque;
1367
        acb = s->aiocb;
1368
    }
1369

    
1370
    drv->bdrv_aio_cancel(acb);
1371
}
1372

    
1373

    
1374
/**************************************************************/
1375
/* async block device emulation */
1376

    
1377
static void bdrv_aio_bh_cb(void *opaque)
1378
{
1379
    BlockDriverAIOCBSync *acb = opaque;
1380
    acb->common.cb(acb->common.opaque, acb->ret);
1381
    qemu_aio_release(acb);
1382
}
1383

    
1384
static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
1385
        int64_t sector_num, uint8_t *buf, int nb_sectors,
1386
        BlockDriverCompletionFunc *cb, void *opaque)
1387
{
1388
    BlockDriverAIOCBSync *acb;
1389
    int ret;
1390

    
1391
    acb = qemu_aio_get(bs, cb, opaque);
1392
    if (!acb->bh)
1393
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1394
    ret = bdrv_read(bs, sector_num, buf, nb_sectors);
1395
    acb->ret = ret;
1396
    qemu_bh_schedule(acb->bh);
1397
    return &acb->common;
1398
}
1399

    
1400
static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
1401
        int64_t sector_num, const uint8_t *buf, int nb_sectors,
1402
        BlockDriverCompletionFunc *cb, void *opaque)
1403
{
1404
    BlockDriverAIOCBSync *acb;
1405
    int ret;
1406

    
1407
    acb = qemu_aio_get(bs, cb, opaque);
1408
    if (!acb->bh)
1409
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1410
    ret = bdrv_write(bs, sector_num, buf, nb_sectors);
1411
    acb->ret = ret;
1412
    qemu_bh_schedule(acb->bh);
1413
    return &acb->common;
1414
}
1415

    
1416
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1417
{
1418
    BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1419
    qemu_bh_cancel(acb->bh);
1420
    qemu_aio_release(acb);
1421
}
1422

    
1423
/**************************************************************/
1424
/* sync block device emulation */
1425

    
1426
static void bdrv_rw_em_cb(void *opaque, int ret)
1427
{
1428
    *(int *)opaque = ret;
1429
}
1430

    
1431
#define NOT_DONE 0x7fffffff
1432

    
1433
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1434
                        uint8_t *buf, int nb_sectors)
1435
{
1436
    int async_ret;
1437
    BlockDriverAIOCB *acb;
1438

    
1439
    async_ret = NOT_DONE;
1440
    acb = bdrv_aio_read(bs, sector_num, buf, nb_sectors,
1441
                        bdrv_rw_em_cb, &async_ret);
1442
    if (acb == NULL)
1443
        return -1;
1444

    
1445
    while (async_ret == NOT_DONE) {
1446
        qemu_aio_wait();
1447
    }
1448

    
1449
    return async_ret;
1450
}
1451

    
1452
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1453
                         const uint8_t *buf, int nb_sectors)
1454
{
1455
    int async_ret;
1456
    BlockDriverAIOCB *acb;
1457

    
1458
    async_ret = NOT_DONE;
1459
    acb = bdrv_aio_write(bs, sector_num, buf, nb_sectors,
1460
                         bdrv_rw_em_cb, &async_ret);
1461
    if (acb == NULL)
1462
        return -1;
1463
    while (async_ret == NOT_DONE) {
1464
        qemu_aio_wait();
1465
    }
1466
    return async_ret;
1467
}
1468

    
1469
void bdrv_init(void)
1470
{
1471
    bdrv_register(&bdrv_raw);
1472
    bdrv_register(&bdrv_host_device);
1473
#ifndef _WIN32
1474
    bdrv_register(&bdrv_cow);
1475
#endif
1476
    bdrv_register(&bdrv_qcow);
1477
    bdrv_register(&bdrv_vmdk);
1478
    bdrv_register(&bdrv_cloop);
1479
    bdrv_register(&bdrv_dmg);
1480
    bdrv_register(&bdrv_bochs);
1481
    bdrv_register(&bdrv_vpc);
1482
    bdrv_register(&bdrv_vvfat);
1483
    bdrv_register(&bdrv_qcow2);
1484
    bdrv_register(&bdrv_parallels);
1485
    bdrv_register(&bdrv_nbd);
1486
}
1487

    
1488
void *qemu_aio_get(BlockDriverState *bs, BlockDriverCompletionFunc *cb,
1489
                   void *opaque)
1490
{
1491
    BlockDriver *drv;
1492
    BlockDriverAIOCB *acb;
1493

    
1494
    drv = bs->drv;
1495
    if (drv->free_aiocb) {
1496
        acb = drv->free_aiocb;
1497
        drv->free_aiocb = acb->next;
1498
    } else {
1499
        acb = qemu_mallocz(drv->aiocb_size);
1500
        if (!acb)
1501
            return NULL;
1502
    }
1503
    acb->bs = bs;
1504
    acb->cb = cb;
1505
    acb->opaque = opaque;
1506
    return acb;
1507
}
1508

    
1509
void qemu_aio_release(void *p)
1510
{
1511
    BlockDriverAIOCB *acb = p;
1512
    BlockDriver *drv = acb->bs->drv;
1513
    acb->next = drv->free_aiocb;
1514
    drv->free_aiocb = acb;
1515
}
1516

    
1517
/**************************************************************/
1518
/* removable device support */
1519

    
1520
/**
1521
 * Return TRUE if the media is present
1522
 */
1523
int bdrv_is_inserted(BlockDriverState *bs)
1524
{
1525
    BlockDriver *drv = bs->drv;
1526
    int ret;
1527
    if (!drv)
1528
        return 0;
1529
    if (!drv->bdrv_is_inserted)
1530
        return 1;
1531
    ret = drv->bdrv_is_inserted(bs);
1532
    return ret;
1533
}
1534

    
1535
/**
1536
 * Return TRUE if the media changed since the last call to this
1537
 * function. It is currently only used for floppy disks
1538
 */
1539
int bdrv_media_changed(BlockDriverState *bs)
1540
{
1541
    BlockDriver *drv = bs->drv;
1542
    int ret;
1543

    
1544
    if (!drv || !drv->bdrv_media_changed)
1545
        ret = -ENOTSUP;
1546
    else
1547
        ret = drv->bdrv_media_changed(bs);
1548
    if (ret == -ENOTSUP)
1549
        ret = bs->media_changed;
1550
    bs->media_changed = 0;
1551
    return ret;
1552
}
1553

    
1554
/**
1555
 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
1556
 */
1557
void bdrv_eject(BlockDriverState *bs, int eject_flag)
1558
{
1559
    BlockDriver *drv = bs->drv;
1560
    int ret;
1561

    
1562
    if (!drv || !drv->bdrv_eject) {
1563
        ret = -ENOTSUP;
1564
    } else {
1565
        ret = drv->bdrv_eject(bs, eject_flag);
1566
    }
1567
    if (ret == -ENOTSUP) {
1568
        if (eject_flag)
1569
            bdrv_close(bs);
1570
    }
1571
}
1572

    
1573
int bdrv_is_locked(BlockDriverState *bs)
1574
{
1575
    return bs->locked;
1576
}
1577

    
1578
/**
1579
 * Lock or unlock the media (if it is locked, the user won't be able
1580
 * to eject it manually).
1581
 */
1582
void bdrv_set_locked(BlockDriverState *bs, int locked)
1583
{
1584
    BlockDriver *drv = bs->drv;
1585

    
1586
    bs->locked = locked;
1587
    if (drv && drv->bdrv_set_locked) {
1588
        drv->bdrv_set_locked(bs, locked);
1589
    }
1590
}
1591

    
1592
/* needed for generic scsi interface */
1593

    
1594
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
1595
{
1596
    BlockDriver *drv = bs->drv;
1597

    
1598
    if (drv && drv->bdrv_ioctl)
1599
        return drv->bdrv_ioctl(bs, req, buf);
1600
    return -ENOTSUP;
1601
}