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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
 *
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 * 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 HOST_BSD
26
/* include native header before sys-queue.h */
27
#include <sys/queue.h>
28
#endif
29

    
30
#include "qemu-common.h"
31
#include "monitor.h"
32
#include "block_int.h"
33
#include "module.h"
34

    
35
#ifdef HOST_BSD
36
#include <sys/types.h>
37
#include <sys/stat.h>
38
#include <sys/ioctl.h>
39
#ifndef __DragonFly__
40
#include <sys/disk.h>
41
#endif
42
#endif
43

    
44
#ifdef _WIN32
45
#include <windows.h>
46
#endif
47

    
48
#define SECTOR_BITS 9
49
#define SECTOR_SIZE (1 << SECTOR_BITS)
50

    
51
typedef struct BlockDriverAIOCBSync {
52
    BlockDriverAIOCB common;
53
    QEMUBH *bh;
54
    int ret;
55
    /* vector translation state */
56
    QEMUIOVector *qiov;
57
    uint8_t *bounce;
58
    int is_write;
59
} BlockDriverAIOCBSync;
60

    
61
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
62
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
63
        BlockDriverCompletionFunc *cb, void *opaque);
64
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
65
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
66
        BlockDriverCompletionFunc *cb, void *opaque);
67
static void bdrv_aio_cancel_em(BlockDriverAIOCB *acb);
68
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
69
                        uint8_t *buf, int nb_sectors);
70
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
71
                         const uint8_t *buf, int nb_sectors);
72

    
73
BlockDriverState *bdrv_first;
74

    
75
static BlockDriver *first_drv;
76

    
77
int path_is_absolute(const char *path)
78
{
79
    const char *p;
80
#ifdef _WIN32
81
    /* specific case for names like: "\\.\d:" */
82
    if (*path == '/' || *path == '\\')
83
        return 1;
84
#endif
85
    p = strchr(path, ':');
86
    if (p)
87
        p++;
88
    else
89
        p = path;
90
#ifdef _WIN32
91
    return (*p == '/' || *p == '\\');
92
#else
93
    return (*p == '/');
94
#endif
95
}
96

    
97
/* if filename is absolute, just copy it to dest. Otherwise, build a
98
   path to it by considering it is relative to base_path. URL are
99
   supported. */
100
void path_combine(char *dest, int dest_size,
101
                  const char *base_path,
102
                  const char *filename)
103
{
104
    const char *p, *p1;
105
    int len;
106

    
107
    if (dest_size <= 0)
108
        return;
109
    if (path_is_absolute(filename)) {
110
        pstrcpy(dest, dest_size, filename);
111
    } else {
112
        p = strchr(base_path, ':');
113
        if (p)
114
            p++;
115
        else
116
            p = base_path;
117
        p1 = strrchr(base_path, '/');
118
#ifdef _WIN32
119
        {
120
            const char *p2;
121
            p2 = strrchr(base_path, '\\');
122
            if (!p1 || p2 > p1)
123
                p1 = p2;
124
        }
125
#endif
126
        if (p1)
127
            p1++;
128
        else
129
            p1 = base_path;
130
        if (p1 > p)
131
            p = p1;
132
        len = p - base_path;
133
        if (len > dest_size - 1)
134
            len = dest_size - 1;
135
        memcpy(dest, base_path, len);
136
        dest[len] = '\0';
137
        pstrcat(dest, dest_size, filename);
138
    }
139
}
140

    
141

    
142
void bdrv_register(BlockDriver *bdrv)
143
{
144
    if (!bdrv->bdrv_aio_readv) {
145
        /* add AIO emulation layer */
146
        bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
147
        bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
148
        bdrv->bdrv_aio_cancel = bdrv_aio_cancel_em;
149
        bdrv->aiocb_size = sizeof(BlockDriverAIOCBSync);
150
    } else if (!bdrv->bdrv_read) {
151
        /* add synchronous IO emulation layer */
152
        bdrv->bdrv_read = bdrv_read_em;
153
        bdrv->bdrv_write = bdrv_write_em;
154
    }
155
    aio_pool_init(&bdrv->aio_pool, bdrv->aiocb_size, bdrv->bdrv_aio_cancel);
156
    bdrv->next = first_drv;
157
    first_drv = bdrv;
158
}
159

    
160
/* create a new block device (by default it is empty) */
161
BlockDriverState *bdrv_new(const char *device_name)
162
{
163
    BlockDriverState **pbs, *bs;
164

    
165
    bs = qemu_mallocz(sizeof(BlockDriverState));
166
    pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
167
    if (device_name[0] != '\0') {
168
        /* insert at the end */
169
        pbs = &bdrv_first;
170
        while (*pbs != NULL)
171
            pbs = &(*pbs)->next;
172
        *pbs = bs;
173
    }
174
    return bs;
175
}
176

    
177
BlockDriver *bdrv_find_format(const char *format_name)
178
{
179
    BlockDriver *drv1;
180
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
181
        if (!strcmp(drv1->format_name, format_name))
182
            return drv1;
183
    }
184
    return NULL;
185
}
186

    
187
int bdrv_create2(BlockDriver *drv,
188
                const char *filename, int64_t size_in_sectors,
189
                const char *backing_file, const char *backing_format,
190
                int flags)
191
{
192
    if (drv->bdrv_create2)
193
        return drv->bdrv_create2(filename, size_in_sectors, backing_file,
194
                                 backing_format, flags);
195
    if (drv->bdrv_create)
196
        return drv->bdrv_create(filename, size_in_sectors, backing_file,
197
                                flags);
198
    return -ENOTSUP;
199
}
200

    
201
int bdrv_create(BlockDriver *drv,
202
                const char *filename, int64_t size_in_sectors,
203
                const char *backing_file, int flags)
204
{
205
    if (!drv->bdrv_create)
206
        return -ENOTSUP;
207
    return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
208
}
209

    
210
#ifdef _WIN32
211
void get_tmp_filename(char *filename, int size)
212
{
213
    char temp_dir[MAX_PATH];
214

    
215
    GetTempPath(MAX_PATH, temp_dir);
216
    GetTempFileName(temp_dir, "qem", 0, filename);
217
}
218
#else
219
void get_tmp_filename(char *filename, int size)
220
{
221
    int fd;
222
    const char *tmpdir;
223
    /* XXX: race condition possible */
224
    tmpdir = getenv("TMPDIR");
225
    if (!tmpdir)
226
        tmpdir = "/tmp";
227
    snprintf(filename, size, "%s/vl.XXXXXX", tmpdir);
228
    fd = mkstemp(filename);
229
    close(fd);
230
}
231
#endif
232

    
233
#ifdef _WIN32
234
static int is_windows_drive_prefix(const char *filename)
235
{
236
    return (((filename[0] >= 'a' && filename[0] <= 'z') ||
237
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
238
            filename[1] == ':');
239
}
240

    
241
static int is_windows_drive(const char *filename)
242
{
243
    if (is_windows_drive_prefix(filename) &&
244
        filename[2] == '\0')
245
        return 1;
246
    if (strstart(filename, "\\\\.\\", NULL) ||
247
        strstart(filename, "//./", NULL))
248
        return 1;
249
    return 0;
250
}
251
#endif
252

    
253
static BlockDriver *find_protocol(const char *filename)
254
{
255
    BlockDriver *drv1;
256
    char protocol[128];
257
    int len;
258
    const char *p;
259

    
260
#ifdef _WIN32
261
    if (is_windows_drive(filename) ||
262
        is_windows_drive_prefix(filename))
263
        return bdrv_find_format("raw");
264
#endif
265
    p = strchr(filename, ':');
266
    if (!p)
267
        return bdrv_find_format("raw");
268
    len = p - filename;
269
    if (len > sizeof(protocol) - 1)
270
        len = sizeof(protocol) - 1;
271
    memcpy(protocol, filename, len);
272
    protocol[len] = '\0';
273
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
274
        if (drv1->protocol_name &&
275
            !strcmp(drv1->protocol_name, protocol))
276
            return drv1;
277
    }
278
    return NULL;
279
}
280

    
281
/* XXX: force raw format if block or character device ? It would
282
   simplify the BSD case */
283
static BlockDriver *find_image_format(const char *filename)
284
{
285
    int ret, score, score_max;
286
    BlockDriver *drv1, *drv;
287
    uint8_t buf[2048];
288
    BlockDriverState *bs;
289

    
290
    /* detect host devices. By convention, /dev/cdrom[N] is always
291
       recognized as a host CDROM */
292
    if (strstart(filename, "/dev/cdrom", NULL))
293
        return bdrv_find_format("host_device");
294
#ifdef _WIN32
295
    if (is_windows_drive(filename))
296
        return bdrv_find_format("host_device");
297
#else
298
    {
299
        struct stat st;
300
        if (stat(filename, &st) >= 0 &&
301
            (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
302
            return bdrv_find_format("host_device");
303
        }
304
    }
305
#endif
306

    
307
    drv = find_protocol(filename);
308
    /* no need to test disk image formats for vvfat */
309
    if (strcmp(drv->format_name, "vvfat") == 0)
310
        return drv;
311

    
312
    ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
313
    if (ret < 0)
314
        return NULL;
315
    ret = bdrv_pread(bs, 0, buf, sizeof(buf));
316
    bdrv_delete(bs);
317
    if (ret < 0) {
318
        return NULL;
319
    }
320

    
321
    score_max = 0;
322
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
323
        if (drv1->bdrv_probe) {
324
            score = drv1->bdrv_probe(buf, ret, filename);
325
            if (score > score_max) {
326
                score_max = score;
327
                drv = drv1;
328
            }
329
        }
330
    }
331
    return drv;
332
}
333

    
334
int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
335
{
336
    BlockDriverState *bs;
337
    int ret;
338

    
339
    bs = bdrv_new("");
340
    ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL);
341
    if (ret < 0) {
342
        bdrv_delete(bs);
343
        return ret;
344
    }
345
    bs->growable = 1;
346
    *pbs = bs;
347
    return 0;
348
}
349

    
350
int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
351
{
352
    return bdrv_open2(bs, filename, flags, NULL);
353
}
354

    
355
int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
356
               BlockDriver *drv)
357
{
358
    int ret, open_flags;
359
    char tmp_filename[PATH_MAX];
360
    char backing_filename[PATH_MAX];
361

    
362
    bs->read_only = 0;
363
    bs->is_temporary = 0;
364
    bs->encrypted = 0;
365
    bs->valid_key = 0;
366
    /* buffer_alignment defaulted to 512, drivers can change this value */
367
    bs->buffer_alignment = 512;
368

    
369
    if (flags & BDRV_O_SNAPSHOT) {
370
        BlockDriverState *bs1;
371
        int64_t total_size;
372
        int is_protocol = 0;
373

    
374
        /* if snapshot, we create a temporary backing file and open it
375
           instead of opening 'filename' directly */
376

    
377
        /* if there is a backing file, use it */
378
        bs1 = bdrv_new("");
379
        ret = bdrv_open2(bs1, filename, 0, drv);
380
        if (ret < 0) {
381
            bdrv_delete(bs1);
382
            return ret;
383
        }
384
        total_size = bdrv_getlength(bs1) >> SECTOR_BITS;
385

    
386
        if (bs1->drv && bs1->drv->protocol_name)
387
            is_protocol = 1;
388

    
389
        bdrv_delete(bs1);
390

    
391
        get_tmp_filename(tmp_filename, sizeof(tmp_filename));
392

    
393
        /* Real path is meaningless for protocols */
394
        if (is_protocol)
395
            snprintf(backing_filename, sizeof(backing_filename),
396
                     "%s", filename);
397
        else
398
            realpath(filename, backing_filename);
399

    
400
        ret = bdrv_create2(bdrv_find_format("qcow2"), tmp_filename,
401
                           total_size, backing_filename, 
402
                           (drv ? drv->format_name : NULL), 0);
403
        if (ret < 0) {
404
            return ret;
405
        }
406
        filename = tmp_filename;
407
        drv = bdrv_find_format("qcow2");
408
        bs->is_temporary = 1;
409
    }
410

    
411
    pstrcpy(bs->filename, sizeof(bs->filename), filename);
412
    if (flags & BDRV_O_FILE) {
413
        drv = find_protocol(filename);
414
    } else if (!drv) {
415
        drv = find_image_format(filename);
416
    }
417
    if (!drv) {
418
        ret = -ENOENT;
419
        goto unlink_and_fail;
420
    }
421
    bs->drv = drv;
422
    bs->opaque = qemu_mallocz(drv->instance_size);
423
    /* Note: for compatibility, we open disk image files as RDWR, and
424
       RDONLY as fallback */
425
    if (!(flags & BDRV_O_FILE))
426
        open_flags = BDRV_O_RDWR | (flags & BDRV_O_CACHE_MASK);
427
    else
428
        open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
429
    ret = drv->bdrv_open(bs, filename, open_flags);
430
    if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) {
431
        ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR);
432
        bs->read_only = 1;
433
    }
434
    if (ret < 0) {
435
        qemu_free(bs->opaque);
436
        bs->opaque = NULL;
437
        bs->drv = NULL;
438
    unlink_and_fail:
439
        if (bs->is_temporary)
440
            unlink(filename);
441
        return ret;
442
    }
443
    if (drv->bdrv_getlength) {
444
        bs->total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
445
    }
446
#ifndef _WIN32
447
    if (bs->is_temporary) {
448
        unlink(filename);
449
    }
450
#endif
451
    if (bs->backing_file[0] != '\0') {
452
        /* if there is a backing file, use it */
453
        BlockDriver *back_drv = NULL;
454
        bs->backing_hd = bdrv_new("");
455
        path_combine(backing_filename, sizeof(backing_filename),
456
                     filename, bs->backing_file);
457
        if (bs->backing_format[0] != '\0')
458
            back_drv = bdrv_find_format(bs->backing_format);
459
        ret = bdrv_open2(bs->backing_hd, backing_filename, open_flags,
460
                         back_drv);
461
        if (ret < 0) {
462
            bdrv_close(bs);
463
            return ret;
464
        }
465
    }
466

    
467
    if (!bdrv_key_required(bs)) {
468
        /* call the change callback */
469
        bs->media_changed = 1;
470
        if (bs->change_cb)
471
            bs->change_cb(bs->change_opaque);
472
    }
473
    return 0;
474
}
475

    
476
void bdrv_close(BlockDriverState *bs)
477
{
478
    if (bs->drv) {
479
        if (bs->backing_hd)
480
            bdrv_delete(bs->backing_hd);
481
        bs->drv->bdrv_close(bs);
482
        qemu_free(bs->opaque);
483
#ifdef _WIN32
484
        if (bs->is_temporary) {
485
            unlink(bs->filename);
486
        }
487
#endif
488
        bs->opaque = NULL;
489
        bs->drv = NULL;
490

    
491
        /* call the change callback */
492
        bs->media_changed = 1;
493
        if (bs->change_cb)
494
            bs->change_cb(bs->change_opaque);
495
    }
496
}
497

    
498
void bdrv_delete(BlockDriverState *bs)
499
{
500
    BlockDriverState **pbs;
501

    
502
    pbs = &bdrv_first;
503
    while (*pbs != bs && *pbs != NULL)
504
        pbs = &(*pbs)->next;
505
    if (*pbs == bs)
506
        *pbs = bs->next;
507

    
508
    bdrv_close(bs);
509
    qemu_free(bs);
510
}
511

    
512
/*
513
 * Run consistency checks on an image
514
 *
515
 * Returns the number of errors or -errno when an internal error occurs
516
 */
517
int bdrv_check(BlockDriverState *bs)
518
{
519
    if (bs->drv->bdrv_check == NULL) {
520
        return -ENOTSUP;
521
    }
522

    
523
    return bs->drv->bdrv_check(bs);
524
}
525

    
526
/* commit COW file into the raw image */
527
int bdrv_commit(BlockDriverState *bs)
528
{
529
    BlockDriver *drv = bs->drv;
530
    int64_t i, total_sectors;
531
    int n, j;
532
    unsigned char sector[512];
533

    
534
    if (!drv)
535
        return -ENOMEDIUM;
536

    
537
    if (bs->read_only) {
538
        return -EACCES;
539
    }
540

    
541
    if (!bs->backing_hd) {
542
        return -ENOTSUP;
543
    }
544

    
545
    total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
546
    for (i = 0; i < total_sectors;) {
547
        if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
548
            for(j = 0; j < n; j++) {
549
                if (bdrv_read(bs, i, sector, 1) != 0) {
550
                    return -EIO;
551
                }
552

    
553
                if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
554
                    return -EIO;
555
                }
556
                i++;
557
            }
558
        } else {
559
            i += n;
560
        }
561
    }
562

    
563
    if (drv->bdrv_make_empty)
564
        return drv->bdrv_make_empty(bs);
565

    
566
    return 0;
567
}
568

    
569
static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
570
                                   size_t size)
571
{
572
    int64_t len;
573

    
574
    if (!bdrv_is_inserted(bs))
575
        return -ENOMEDIUM;
576

    
577
    if (bs->growable)
578
        return 0;
579

    
580
    len = bdrv_getlength(bs);
581

    
582
    if (offset < 0)
583
        return -EIO;
584

    
585
    if ((offset > len) || (len - offset < size))
586
        return -EIO;
587

    
588
    return 0;
589
}
590

    
591
static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
592
                              int nb_sectors)
593
{
594
    return bdrv_check_byte_request(bs, sector_num * 512, nb_sectors * 512);
595
}
596

    
597
/* return < 0 if error. See bdrv_write() for the return codes */
598
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
599
              uint8_t *buf, int nb_sectors)
600
{
601
    BlockDriver *drv = bs->drv;
602

    
603
    if (!drv)
604
        return -ENOMEDIUM;
605
    if (bdrv_check_request(bs, sector_num, nb_sectors))
606
        return -EIO;
607

    
608
    return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
609
}
610

    
611
/* Return < 0 if error. Important errors are:
612
  -EIO         generic I/O error (may happen for all errors)
613
  -ENOMEDIUM   No media inserted.
614
  -EINVAL      Invalid sector number or nb_sectors
615
  -EACCES      Trying to write a read-only device
616
*/
617
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
618
               const uint8_t *buf, int nb_sectors)
619
{
620
    BlockDriver *drv = bs->drv;
621
    if (!bs->drv)
622
        return -ENOMEDIUM;
623
    if (bs->read_only)
624
        return -EACCES;
625
    if (bdrv_check_request(bs, sector_num, nb_sectors))
626
        return -EIO;
627

    
628
    return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
629
}
630

    
631
int bdrv_pread(BlockDriverState *bs, int64_t offset,
632
               void *buf, int count1)
633
{
634
    uint8_t tmp_buf[SECTOR_SIZE];
635
    int len, nb_sectors, count;
636
    int64_t sector_num;
637

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

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

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

    
675
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
676
                const void *buf, int count1)
677
{
678
    uint8_t tmp_buf[SECTOR_SIZE];
679
    int len, nb_sectors, count;
680
    int64_t sector_num;
681

    
682
    count = count1;
683
    /* first write to align to sector start */
684
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
685
    if (len > count)
686
        len = count;
687
    sector_num = offset >> SECTOR_BITS;
688
    if (len > 0) {
689
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
690
            return -EIO;
691
        memcpy(tmp_buf + (offset & (SECTOR_SIZE - 1)), buf, len);
692
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
693
            return -EIO;
694
        count -= len;
695
        if (count == 0)
696
            return count1;
697
        sector_num++;
698
        buf += len;
699
    }
700

    
701
    /* write the sectors "in place" */
702
    nb_sectors = count >> SECTOR_BITS;
703
    if (nb_sectors > 0) {
704
        if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
705
            return -EIO;
706
        sector_num += nb_sectors;
707
        len = nb_sectors << SECTOR_BITS;
708
        buf += len;
709
        count -= len;
710
    }
711

    
712
    /* add data from the last sector */
713
    if (count > 0) {
714
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
715
            return -EIO;
716
        memcpy(tmp_buf, buf, count);
717
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
718
            return -EIO;
719
    }
720
    return count1;
721
}
722

    
723
/**
724
 * Truncate file to 'offset' bytes (needed only for file protocols)
725
 */
726
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
727
{
728
    BlockDriver *drv = bs->drv;
729
    if (!drv)
730
        return -ENOMEDIUM;
731
    if (!drv->bdrv_truncate)
732
        return -ENOTSUP;
733
    return drv->bdrv_truncate(bs, offset);
734
}
735

    
736
/**
737
 * Length of a file in bytes. Return < 0 if error or unknown.
738
 */
739
int64_t bdrv_getlength(BlockDriverState *bs)
740
{
741
    BlockDriver *drv = bs->drv;
742
    if (!drv)
743
        return -ENOMEDIUM;
744
    if (!drv->bdrv_getlength) {
745
        /* legacy mode */
746
        return bs->total_sectors * SECTOR_SIZE;
747
    }
748
    return drv->bdrv_getlength(bs);
749
}
750

    
751
/* return 0 as number of sectors if no device present or error */
752
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
753
{
754
    int64_t length;
755
    length = bdrv_getlength(bs);
756
    if (length < 0)
757
        length = 0;
758
    else
759
        length = length >> SECTOR_BITS;
760
    *nb_sectors_ptr = length;
761
}
762

    
763
struct partition {
764
        uint8_t boot_ind;           /* 0x80 - active */
765
        uint8_t head;               /* starting head */
766
        uint8_t sector;             /* starting sector */
767
        uint8_t cyl;                /* starting cylinder */
768
        uint8_t sys_ind;            /* What partition type */
769
        uint8_t end_head;           /* end head */
770
        uint8_t end_sector;         /* end sector */
771
        uint8_t end_cyl;            /* end cylinder */
772
        uint32_t start_sect;        /* starting sector counting from 0 */
773
        uint32_t nr_sects;          /* nr of sectors in partition */
774
} __attribute__((packed));
775

    
776
/* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
777
static int guess_disk_lchs(BlockDriverState *bs,
778
                           int *pcylinders, int *pheads, int *psectors)
779
{
780
    uint8_t buf[512];
781
    int ret, i, heads, sectors, cylinders;
782
    struct partition *p;
783
    uint32_t nr_sects;
784
    uint64_t nb_sectors;
785

    
786
    bdrv_get_geometry(bs, &nb_sectors);
787

    
788
    ret = bdrv_read(bs, 0, buf, 1);
789
    if (ret < 0)
790
        return -1;
791
    /* test msdos magic */
792
    if (buf[510] != 0x55 || buf[511] != 0xaa)
793
        return -1;
794
    for(i = 0; i < 4; i++) {
795
        p = ((struct partition *)(buf + 0x1be)) + i;
796
        nr_sects = le32_to_cpu(p->nr_sects);
797
        if (nr_sects && p->end_head) {
798
            /* We make the assumption that the partition terminates on
799
               a cylinder boundary */
800
            heads = p->end_head + 1;
801
            sectors = p->end_sector & 63;
802
            if (sectors == 0)
803
                continue;
804
            cylinders = nb_sectors / (heads * sectors);
805
            if (cylinders < 1 || cylinders > 16383)
806
                continue;
807
            *pheads = heads;
808
            *psectors = sectors;
809
            *pcylinders = cylinders;
810
#if 0
811
            printf("guessed geometry: LCHS=%d %d %d\n",
812
                   cylinders, heads, sectors);
813
#endif
814
            return 0;
815
        }
816
    }
817
    return -1;
818
}
819

    
820
void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
821
{
822
    int translation, lba_detected = 0;
823
    int cylinders, heads, secs;
824
    uint64_t nb_sectors;
825

    
826
    /* if a geometry hint is available, use it */
827
    bdrv_get_geometry(bs, &nb_sectors);
828
    bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
829
    translation = bdrv_get_translation_hint(bs);
830
    if (cylinders != 0) {
831
        *pcyls = cylinders;
832
        *pheads = heads;
833
        *psecs = secs;
834
    } else {
835
        if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
836
            if (heads > 16) {
837
                /* if heads > 16, it means that a BIOS LBA
838
                   translation was active, so the default
839
                   hardware geometry is OK */
840
                lba_detected = 1;
841
                goto default_geometry;
842
            } else {
843
                *pcyls = cylinders;
844
                *pheads = heads;
845
                *psecs = secs;
846
                /* disable any translation to be in sync with
847
                   the logical geometry */
848
                if (translation == BIOS_ATA_TRANSLATION_AUTO) {
849
                    bdrv_set_translation_hint(bs,
850
                                              BIOS_ATA_TRANSLATION_NONE);
851
                }
852
            }
853
        } else {
854
        default_geometry:
855
            /* if no geometry, use a standard physical disk geometry */
856
            cylinders = nb_sectors / (16 * 63);
857

    
858
            if (cylinders > 16383)
859
                cylinders = 16383;
860
            else if (cylinders < 2)
861
                cylinders = 2;
862
            *pcyls = cylinders;
863
            *pheads = 16;
864
            *psecs = 63;
865
            if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
866
                if ((*pcyls * *pheads) <= 131072) {
867
                    bdrv_set_translation_hint(bs,
868
                                              BIOS_ATA_TRANSLATION_LARGE);
869
                } else {
870
                    bdrv_set_translation_hint(bs,
871
                                              BIOS_ATA_TRANSLATION_LBA);
872
                }
873
            }
874
        }
875
        bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
876
    }
877
}
878

    
879
void bdrv_set_geometry_hint(BlockDriverState *bs,
880
                            int cyls, int heads, int secs)
881
{
882
    bs->cyls = cyls;
883
    bs->heads = heads;
884
    bs->secs = secs;
885
}
886

    
887
void bdrv_set_type_hint(BlockDriverState *bs, int type)
888
{
889
    bs->type = type;
890
    bs->removable = ((type == BDRV_TYPE_CDROM ||
891
                      type == BDRV_TYPE_FLOPPY));
892
}
893

    
894
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
895
{
896
    bs->translation = translation;
897
}
898

    
899
void bdrv_get_geometry_hint(BlockDriverState *bs,
900
                            int *pcyls, int *pheads, int *psecs)
901
{
902
    *pcyls = bs->cyls;
903
    *pheads = bs->heads;
904
    *psecs = bs->secs;
905
}
906

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

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

    
917
int bdrv_is_removable(BlockDriverState *bs)
918
{
919
    return bs->removable;
920
}
921

    
922
int bdrv_is_read_only(BlockDriverState *bs)
923
{
924
    return bs->read_only;
925
}
926

    
927
int bdrv_is_sg(BlockDriverState *bs)
928
{
929
    return bs->sg;
930
}
931

    
932
/* XXX: no longer used */
933
void bdrv_set_change_cb(BlockDriverState *bs,
934
                        void (*change_cb)(void *opaque), void *opaque)
935
{
936
    bs->change_cb = change_cb;
937
    bs->change_opaque = opaque;
938
}
939

    
940
int bdrv_is_encrypted(BlockDriverState *bs)
941
{
942
    if (bs->backing_hd && bs->backing_hd->encrypted)
943
        return 1;
944
    return bs->encrypted;
945
}
946

    
947
int bdrv_key_required(BlockDriverState *bs)
948
{
949
    BlockDriverState *backing_hd = bs->backing_hd;
950

    
951
    if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
952
        return 1;
953
    return (bs->encrypted && !bs->valid_key);
954
}
955

    
956
int bdrv_set_key(BlockDriverState *bs, const char *key)
957
{
958
    int ret;
959
    if (bs->backing_hd && bs->backing_hd->encrypted) {
960
        ret = bdrv_set_key(bs->backing_hd, key);
961
        if (ret < 0)
962
            return ret;
963
        if (!bs->encrypted)
964
            return 0;
965
    }
966
    if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
967
        return -1;
968
    ret = bs->drv->bdrv_set_key(bs, key);
969
    if (ret < 0) {
970
        bs->valid_key = 0;
971
    } else if (!bs->valid_key) {
972
        bs->valid_key = 1;
973
        /* call the change callback now, we skipped it on open */
974
        bs->media_changed = 1;
975
        if (bs->change_cb)
976
            bs->change_cb(bs->change_opaque);
977
    }
978
    return ret;
979
}
980

    
981
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
982
{
983
    if (!bs->drv) {
984
        buf[0] = '\0';
985
    } else {
986
        pstrcpy(buf, buf_size, bs->drv->format_name);
987
    }
988
}
989

    
990
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
991
                         void *opaque)
992
{
993
    BlockDriver *drv;
994

    
995
    for (drv = first_drv; drv != NULL; drv = drv->next) {
996
        it(opaque, drv->format_name);
997
    }
998
}
999

    
1000
BlockDriverState *bdrv_find(const char *name)
1001
{
1002
    BlockDriverState *bs;
1003

    
1004
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1005
        if (!strcmp(name, bs->device_name))
1006
            return bs;
1007
    }
1008
    return NULL;
1009
}
1010

    
1011
void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
1012
{
1013
    BlockDriverState *bs;
1014

    
1015
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1016
        it(opaque, bs);
1017
    }
1018
}
1019

    
1020
const char *bdrv_get_device_name(BlockDriverState *bs)
1021
{
1022
    return bs->device_name;
1023
}
1024

    
1025
void bdrv_flush(BlockDriverState *bs)
1026
{
1027
    if (!bs->drv)
1028
        return;
1029
    if (bs->drv->bdrv_flush)
1030
        bs->drv->bdrv_flush(bs);
1031
    if (bs->backing_hd)
1032
        bdrv_flush(bs->backing_hd);
1033
}
1034

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

    
1039
    for (bs = bdrv_first; bs != NULL; bs = bs->next)
1040
        if (bs->drv && !bdrv_is_read_only(bs) && 
1041
            (!bdrv_is_removable(bs) || bdrv_is_inserted(bs)))
1042
            bdrv_flush(bs);
1043
}
1044

    
1045
/*
1046
 * Returns true iff the specified sector is present in the disk image. Drivers
1047
 * not implementing the functionality are assumed to not support backing files,
1048
 * hence all their sectors are reported as allocated.
1049
 *
1050
 * 'pnum' is set to the number of sectors (including and immediately following
1051
 * the specified sector) that are known to be in the same
1052
 * allocated/unallocated state.
1053
 *
1054
 * 'nb_sectors' is the max value 'pnum' should be set to.
1055
 */
1056
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
1057
        int *pnum)
1058
{
1059
    int64_t n;
1060
    if (!bs->drv->bdrv_is_allocated) {
1061
        if (sector_num >= bs->total_sectors) {
1062
            *pnum = 0;
1063
            return 0;
1064
        }
1065
        n = bs->total_sectors - sector_num;
1066
        *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
1067
        return 1;
1068
    }
1069
    return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
1070
}
1071

    
1072
void bdrv_info(Monitor *mon)
1073
{
1074
    BlockDriverState *bs;
1075

    
1076
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1077
        monitor_printf(mon, "%s:", bs->device_name);
1078
        monitor_printf(mon, " type=");
1079
        switch(bs->type) {
1080
        case BDRV_TYPE_HD:
1081
            monitor_printf(mon, "hd");
1082
            break;
1083
        case BDRV_TYPE_CDROM:
1084
            monitor_printf(mon, "cdrom");
1085
            break;
1086
        case BDRV_TYPE_FLOPPY:
1087
            monitor_printf(mon, "floppy");
1088
            break;
1089
        }
1090
        monitor_printf(mon, " removable=%d", bs->removable);
1091
        if (bs->removable) {
1092
            monitor_printf(mon, " locked=%d", bs->locked);
1093
        }
1094
        if (bs->drv) {
1095
            monitor_printf(mon, " file=");
1096
            monitor_print_filename(mon, bs->filename);
1097
            if (bs->backing_file[0] != '\0') {
1098
                monitor_printf(mon, " backing_file=");
1099
                monitor_print_filename(mon, bs->backing_file);
1100
            }
1101
            monitor_printf(mon, " ro=%d", bs->read_only);
1102
            monitor_printf(mon, " drv=%s", bs->drv->format_name);
1103
            monitor_printf(mon, " encrypted=%d", bdrv_is_encrypted(bs));
1104
        } else {
1105
            monitor_printf(mon, " [not inserted]");
1106
        }
1107
        monitor_printf(mon, "\n");
1108
    }
1109
}
1110

    
1111
/* The "info blockstats" command. */
1112
void bdrv_info_stats(Monitor *mon)
1113
{
1114
    BlockDriverState *bs;
1115

    
1116
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1117
        monitor_printf(mon, "%s:"
1118
                       " rd_bytes=%" PRIu64
1119
                       " wr_bytes=%" PRIu64
1120
                       " rd_operations=%" PRIu64
1121
                       " wr_operations=%" PRIu64
1122
                       "\n",
1123
                       bs->device_name,
1124
                       bs->rd_bytes, bs->wr_bytes,
1125
                       bs->rd_ops, bs->wr_ops);
1126
    }
1127
}
1128

    
1129
const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
1130
{
1131
    if (bs->backing_hd && bs->backing_hd->encrypted)
1132
        return bs->backing_file;
1133
    else if (bs->encrypted)
1134
        return bs->filename;
1135
    else
1136
        return NULL;
1137
}
1138

    
1139
void bdrv_get_backing_filename(BlockDriverState *bs,
1140
                               char *filename, int filename_size)
1141
{
1142
    if (!bs->backing_hd) {
1143
        pstrcpy(filename, filename_size, "");
1144
    } else {
1145
        pstrcpy(filename, filename_size, bs->backing_file);
1146
    }
1147
}
1148

    
1149
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
1150
                          const uint8_t *buf, int nb_sectors)
1151
{
1152
    BlockDriver *drv = bs->drv;
1153
    if (!drv)
1154
        return -ENOMEDIUM;
1155
    if (!drv->bdrv_write_compressed)
1156
        return -ENOTSUP;
1157
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1158
        return -EIO;
1159
    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
1160
}
1161

    
1162
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1163
{
1164
    BlockDriver *drv = bs->drv;
1165
    if (!drv)
1166
        return -ENOMEDIUM;
1167
    if (!drv->bdrv_get_info)
1168
        return -ENOTSUP;
1169
    memset(bdi, 0, sizeof(*bdi));
1170
    return drv->bdrv_get_info(bs, bdi);
1171
}
1172

    
1173
int bdrv_put_buffer(BlockDriverState *bs, const uint8_t *buf, int64_t pos, int size)
1174
{
1175
    BlockDriver *drv = bs->drv;
1176
    if (!drv)
1177
        return -ENOMEDIUM;
1178
    if (!drv->bdrv_put_buffer)
1179
        return -ENOTSUP;
1180
    return drv->bdrv_put_buffer(bs, buf, pos, size);
1181
}
1182

    
1183
int bdrv_get_buffer(BlockDriverState *bs, uint8_t *buf, int64_t pos, int size)
1184
{
1185
    BlockDriver *drv = bs->drv;
1186
    if (!drv)
1187
        return -ENOMEDIUM;
1188
    if (!drv->bdrv_get_buffer)
1189
        return -ENOTSUP;
1190
    return drv->bdrv_get_buffer(bs, buf, pos, size);
1191
}
1192

    
1193
/**************************************************************/
1194
/* handling of snapshots */
1195

    
1196
int bdrv_snapshot_create(BlockDriverState *bs,
1197
                         QEMUSnapshotInfo *sn_info)
1198
{
1199
    BlockDriver *drv = bs->drv;
1200
    if (!drv)
1201
        return -ENOMEDIUM;
1202
    if (!drv->bdrv_snapshot_create)
1203
        return -ENOTSUP;
1204
    return drv->bdrv_snapshot_create(bs, sn_info);
1205
}
1206

    
1207
int bdrv_snapshot_goto(BlockDriverState *bs,
1208
                       const char *snapshot_id)
1209
{
1210
    BlockDriver *drv = bs->drv;
1211
    if (!drv)
1212
        return -ENOMEDIUM;
1213
    if (!drv->bdrv_snapshot_goto)
1214
        return -ENOTSUP;
1215
    return drv->bdrv_snapshot_goto(bs, snapshot_id);
1216
}
1217

    
1218
int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
1219
{
1220
    BlockDriver *drv = bs->drv;
1221
    if (!drv)
1222
        return -ENOMEDIUM;
1223
    if (!drv->bdrv_snapshot_delete)
1224
        return -ENOTSUP;
1225
    return drv->bdrv_snapshot_delete(bs, snapshot_id);
1226
}
1227

    
1228
int bdrv_snapshot_list(BlockDriverState *bs,
1229
                       QEMUSnapshotInfo **psn_info)
1230
{
1231
    BlockDriver *drv = bs->drv;
1232
    if (!drv)
1233
        return -ENOMEDIUM;
1234
    if (!drv->bdrv_snapshot_list)
1235
        return -ENOTSUP;
1236
    return drv->bdrv_snapshot_list(bs, psn_info);
1237
}
1238

    
1239
#define NB_SUFFIXES 4
1240

    
1241
char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1242
{
1243
    static const char suffixes[NB_SUFFIXES] = "KMGT";
1244
    int64_t base;
1245
    int i;
1246

    
1247
    if (size <= 999) {
1248
        snprintf(buf, buf_size, "%" PRId64, size);
1249
    } else {
1250
        base = 1024;
1251
        for(i = 0; i < NB_SUFFIXES; i++) {
1252
            if (size < (10 * base)) {
1253
                snprintf(buf, buf_size, "%0.1f%c",
1254
                         (double)size / base,
1255
                         suffixes[i]);
1256
                break;
1257
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1258
                snprintf(buf, buf_size, "%" PRId64 "%c",
1259
                         ((size + (base >> 1)) / base),
1260
                         suffixes[i]);
1261
                break;
1262
            }
1263
            base = base * 1024;
1264
        }
1265
    }
1266
    return buf;
1267
}
1268

    
1269
char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1270
{
1271
    char buf1[128], date_buf[128], clock_buf[128];
1272
#ifdef _WIN32
1273
    struct tm *ptm;
1274
#else
1275
    struct tm tm;
1276
#endif
1277
    time_t ti;
1278
    int64_t secs;
1279

    
1280
    if (!sn) {
1281
        snprintf(buf, buf_size,
1282
                 "%-10s%-20s%7s%20s%15s",
1283
                 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1284
    } else {
1285
        ti = sn->date_sec;
1286
#ifdef _WIN32
1287
        ptm = localtime(&ti);
1288
        strftime(date_buf, sizeof(date_buf),
1289
                 "%Y-%m-%d %H:%M:%S", ptm);
1290
#else
1291
        localtime_r(&ti, &tm);
1292
        strftime(date_buf, sizeof(date_buf),
1293
                 "%Y-%m-%d %H:%M:%S", &tm);
1294
#endif
1295
        secs = sn->vm_clock_nsec / 1000000000;
1296
        snprintf(clock_buf, sizeof(clock_buf),
1297
                 "%02d:%02d:%02d.%03d",
1298
                 (int)(secs / 3600),
1299
                 (int)((secs / 60) % 60),
1300
                 (int)(secs % 60),
1301
                 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1302
        snprintf(buf, buf_size,
1303
                 "%-10s%-20s%7s%20s%15s",
1304
                 sn->id_str, sn->name,
1305
                 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1306
                 date_buf,
1307
                 clock_buf);
1308
    }
1309
    return buf;
1310
}
1311

    
1312

    
1313
/**************************************************************/
1314
/* async I/Os */
1315

    
1316
BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
1317
                                 QEMUIOVector *qiov, int nb_sectors,
1318
                                 BlockDriverCompletionFunc *cb, void *opaque)
1319
{
1320
    BlockDriver *drv = bs->drv;
1321
    BlockDriverAIOCB *ret;
1322

    
1323
    if (!drv)
1324
        return NULL;
1325
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1326
        return NULL;
1327

    
1328
    ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
1329
                              cb, opaque);
1330

    
1331
    if (ret) {
1332
        /* Update stats even though technically transfer has not happened. */
1333
        bs->rd_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1334
        bs->rd_ops ++;
1335
    }
1336

    
1337
    return ret;
1338
}
1339

    
1340
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
1341
                                  QEMUIOVector *qiov, int nb_sectors,
1342
                                  BlockDriverCompletionFunc *cb, void *opaque)
1343
{
1344
    BlockDriver *drv = bs->drv;
1345
    BlockDriverAIOCB *ret;
1346

    
1347
    if (!drv)
1348
        return NULL;
1349
    if (bs->read_only)
1350
        return NULL;
1351
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1352
        return NULL;
1353

    
1354
    ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors,
1355
                               cb, opaque);
1356

    
1357
    if (ret) {
1358
        /* Update stats even though technically transfer has not happened. */
1359
        bs->wr_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1360
        bs->wr_ops ++;
1361
    }
1362

    
1363
    return ret;
1364
}
1365

    
1366
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1367
{
1368
    acb->pool->cancel(acb);
1369
}
1370

    
1371

    
1372
/**************************************************************/
1373
/* async block device emulation */
1374

    
1375
static void bdrv_aio_bh_cb(void *opaque)
1376
{
1377
    BlockDriverAIOCBSync *acb = opaque;
1378

    
1379
    if (!acb->is_write)
1380
        qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size);
1381
    qemu_vfree(acb->bounce);
1382
    acb->common.cb(acb->common.opaque, acb->ret);
1383

    
1384
    qemu_aio_release(acb);
1385
}
1386

    
1387
static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
1388
                                            int64_t sector_num,
1389
                                            QEMUIOVector *qiov,
1390
                                            int nb_sectors,
1391
                                            BlockDriverCompletionFunc *cb,
1392
                                            void *opaque,
1393
                                            int is_write)
1394

    
1395
{
1396
    BlockDriverAIOCBSync *acb;
1397

    
1398
    acb = qemu_aio_get(bs, cb, opaque);
1399
    acb->is_write = is_write;
1400
    acb->qiov = qiov;
1401
    acb->bounce = qemu_blockalign(bs, qiov->size);
1402

    
1403
    if (!acb->bh)
1404
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1405

    
1406
    if (is_write) {
1407
        qemu_iovec_to_buffer(acb->qiov, acb->bounce);
1408
        acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
1409
    } else {
1410
        acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
1411
    }
1412

    
1413
    qemu_bh_schedule(acb->bh);
1414

    
1415
    return &acb->common;
1416
}
1417

    
1418
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
1419
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
1420
        BlockDriverCompletionFunc *cb, void *opaque)
1421
{
1422
    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
1423
}
1424

    
1425
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
1426
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
1427
        BlockDriverCompletionFunc *cb, void *opaque)
1428
{
1429
    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
1430
}
1431

    
1432

    
1433
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1434
{
1435
    BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1436
    qemu_bh_cancel(acb->bh);
1437
    qemu_aio_release(acb);
1438
}
1439

    
1440
/**************************************************************/
1441
/* sync block device emulation */
1442

    
1443
static void bdrv_rw_em_cb(void *opaque, int ret)
1444
{
1445
    *(int *)opaque = ret;
1446
}
1447

    
1448
#define NOT_DONE 0x7fffffff
1449

    
1450
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1451
                        uint8_t *buf, int nb_sectors)
1452
{
1453
    int async_ret;
1454
    BlockDriverAIOCB *acb;
1455
    struct iovec iov;
1456
    QEMUIOVector qiov;
1457

    
1458
    async_ret = NOT_DONE;
1459
    iov.iov_base = (void *)buf;
1460
    iov.iov_len = nb_sectors * 512;
1461
    qemu_iovec_init_external(&qiov, &iov, 1);
1462
    acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors,
1463
        bdrv_rw_em_cb, &async_ret);
1464
    if (acb == NULL)
1465
        return -1;
1466

    
1467
    while (async_ret == NOT_DONE) {
1468
        qemu_aio_wait();
1469
    }
1470

    
1471
    return async_ret;
1472
}
1473

    
1474
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1475
                         const uint8_t *buf, int nb_sectors)
1476
{
1477
    int async_ret;
1478
    BlockDriverAIOCB *acb;
1479
    struct iovec iov;
1480
    QEMUIOVector qiov;
1481

    
1482
    async_ret = NOT_DONE;
1483
    iov.iov_base = (void *)buf;
1484
    iov.iov_len = nb_sectors * 512;
1485
    qemu_iovec_init_external(&qiov, &iov, 1);
1486
    acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors,
1487
        bdrv_rw_em_cb, &async_ret);
1488
    if (acb == NULL)
1489
        return -1;
1490
    while (async_ret == NOT_DONE) {
1491
        qemu_aio_wait();
1492
    }
1493
    return async_ret;
1494
}
1495

    
1496
void bdrv_init(void)
1497
{
1498
    module_call_init(MODULE_INIT_BLOCK);
1499
}
1500

    
1501
void aio_pool_init(AIOPool *pool, int aiocb_size,
1502
                   void (*cancel)(BlockDriverAIOCB *acb))
1503
{
1504
    pool->aiocb_size = aiocb_size;
1505
    pool->cancel = cancel;
1506
    pool->free_aiocb = NULL;
1507
}
1508

    
1509
void *qemu_aio_get_pool(AIOPool *pool, BlockDriverState *bs,
1510
                        BlockDriverCompletionFunc *cb, void *opaque)
1511
{
1512
    BlockDriverAIOCB *acb;
1513

    
1514
    if (pool->free_aiocb) {
1515
        acb = pool->free_aiocb;
1516
        pool->free_aiocb = acb->next;
1517
    } else {
1518
        acb = qemu_mallocz(pool->aiocb_size);
1519
        acb->pool = pool;
1520
    }
1521
    acb->bs = bs;
1522
    acb->cb = cb;
1523
    acb->opaque = opaque;
1524
    return acb;
1525
}
1526

    
1527
void *qemu_aio_get(BlockDriverState *bs, BlockDriverCompletionFunc *cb,
1528
                   void *opaque)
1529
{
1530
    return qemu_aio_get_pool(&bs->drv->aio_pool, bs, cb, opaque);
1531
}
1532

    
1533
void qemu_aio_release(void *p)
1534
{
1535
    BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p;
1536
    AIOPool *pool = acb->pool;
1537
    acb->next = pool->free_aiocb;
1538
    pool->free_aiocb = acb;
1539
}
1540

    
1541
/**************************************************************/
1542
/* removable device support */
1543

    
1544
/**
1545
 * Return TRUE if the media is present
1546
 */
1547
int bdrv_is_inserted(BlockDriverState *bs)
1548
{
1549
    BlockDriver *drv = bs->drv;
1550
    int ret;
1551
    if (!drv)
1552
        return 0;
1553
    if (!drv->bdrv_is_inserted)
1554
        return 1;
1555
    ret = drv->bdrv_is_inserted(bs);
1556
    return ret;
1557
}
1558

    
1559
/**
1560
 * Return TRUE if the media changed since the last call to this
1561
 * function. It is currently only used for floppy disks
1562
 */
1563
int bdrv_media_changed(BlockDriverState *bs)
1564
{
1565
    BlockDriver *drv = bs->drv;
1566
    int ret;
1567

    
1568
    if (!drv || !drv->bdrv_media_changed)
1569
        ret = -ENOTSUP;
1570
    else
1571
        ret = drv->bdrv_media_changed(bs);
1572
    if (ret == -ENOTSUP)
1573
        ret = bs->media_changed;
1574
    bs->media_changed = 0;
1575
    return ret;
1576
}
1577

    
1578
/**
1579
 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
1580
 */
1581
void bdrv_eject(BlockDriverState *bs, int eject_flag)
1582
{
1583
    BlockDriver *drv = bs->drv;
1584
    int ret;
1585

    
1586
    if (!drv || !drv->bdrv_eject) {
1587
        ret = -ENOTSUP;
1588
    } else {
1589
        ret = drv->bdrv_eject(bs, eject_flag);
1590
    }
1591
    if (ret == -ENOTSUP) {
1592
        if (eject_flag)
1593
            bdrv_close(bs);
1594
    }
1595
}
1596

    
1597
int bdrv_is_locked(BlockDriverState *bs)
1598
{
1599
    return bs->locked;
1600
}
1601

    
1602
/**
1603
 * Lock or unlock the media (if it is locked, the user won't be able
1604
 * to eject it manually).
1605
 */
1606
void bdrv_set_locked(BlockDriverState *bs, int locked)
1607
{
1608
    BlockDriver *drv = bs->drv;
1609

    
1610
    bs->locked = locked;
1611
    if (drv && drv->bdrv_set_locked) {
1612
        drv->bdrv_set_locked(bs, locked);
1613
    }
1614
}
1615

    
1616
/* needed for generic scsi interface */
1617

    
1618
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
1619
{
1620
    BlockDriver *drv = bs->drv;
1621

    
1622
    if (drv && drv->bdrv_ioctl)
1623
        return drv->bdrv_ioctl(bs, req, buf);
1624
    return -ENOTSUP;
1625
}
1626

    
1627
BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
1628
        unsigned long int req, void *buf,
1629
        BlockDriverCompletionFunc *cb, void *opaque)
1630
{
1631
    BlockDriver *drv = bs->drv;
1632

    
1633
    if (drv && drv->bdrv_aio_ioctl)
1634
        return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
1635
    return NULL;
1636
}
1637

    
1638
void *qemu_blockalign(BlockDriverState *bs, size_t size)
1639
{
1640
    return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
1641
}