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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 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
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
52
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
53
        BlockDriverCompletionFunc *cb, void *opaque);
54
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
55
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
56
        BlockDriverCompletionFunc *cb, void *opaque);
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
void bdrv_register(BlockDriver *bdrv)
131
{
132
    if (!bdrv->bdrv_aio_readv) {
133
        /* add AIO emulation layer */
134
        bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
135
        bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
136
    } else if (!bdrv->bdrv_read) {
137
        /* add synchronous IO emulation layer */
138
        bdrv->bdrv_read = bdrv_read_em;
139
        bdrv->bdrv_write = bdrv_write_em;
140
    }
141
    bdrv->next = first_drv;
142
    first_drv = bdrv;
143
}
144

    
145
/* create a new block device (by default it is empty) */
146
BlockDriverState *bdrv_new(const char *device_name)
147
{
148
    BlockDriverState **pbs, *bs;
149

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

    
162
BlockDriver *bdrv_find_format(const char *format_name)
163
{
164
    BlockDriver *drv1;
165
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
166
        if (!strcmp(drv1->format_name, format_name))
167
            return drv1;
168
    }
169
    return NULL;
170
}
171

    
172
int bdrv_create(BlockDriver *drv, const char* filename,
173
    QEMUOptionParameter *options)
174
{
175
    if (!drv->bdrv_create)
176
        return -ENOTSUP;
177

    
178
    return drv->bdrv_create(filename, options);
179
}
180

    
181
#ifdef _WIN32
182
void get_tmp_filename(char *filename, int size)
183
{
184
    char temp_dir[MAX_PATH];
185

    
186
    GetTempPath(MAX_PATH, temp_dir);
187
    GetTempFileName(temp_dir, "qem", 0, filename);
188
}
189
#else
190
void get_tmp_filename(char *filename, int size)
191
{
192
    int fd;
193
    const char *tmpdir;
194
    /* XXX: race condition possible */
195
    tmpdir = getenv("TMPDIR");
196
    if (!tmpdir)
197
        tmpdir = "/tmp";
198
    snprintf(filename, size, "%s/vl.XXXXXX", tmpdir);
199
    fd = mkstemp(filename);
200
    close(fd);
201
}
202
#endif
203

    
204
#ifdef _WIN32
205
static int is_windows_drive_prefix(const char *filename)
206
{
207
    return (((filename[0] >= 'a' && filename[0] <= 'z') ||
208
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
209
            filename[1] == ':');
210
}
211

    
212
int is_windows_drive(const char *filename)
213
{
214
    if (is_windows_drive_prefix(filename) &&
215
        filename[2] == '\0')
216
        return 1;
217
    if (strstart(filename, "\\\\.\\", NULL) ||
218
        strstart(filename, "//./", NULL))
219
        return 1;
220
    return 0;
221
}
222
#endif
223

    
224
static BlockDriver *find_protocol(const char *filename)
225
{
226
    BlockDriver *drv1;
227
    char protocol[128];
228
    int len;
229
    const char *p;
230

    
231
#ifdef _WIN32
232
    if (is_windows_drive(filename) ||
233
        is_windows_drive_prefix(filename))
234
        return bdrv_find_format("raw");
235
#endif
236
    p = strchr(filename, ':');
237
    if (!p)
238
        return bdrv_find_format("raw");
239
    len = p - filename;
240
    if (len > sizeof(protocol) - 1)
241
        len = sizeof(protocol) - 1;
242
    memcpy(protocol, filename, len);
243
    protocol[len] = '\0';
244
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
245
        if (drv1->protocol_name &&
246
            !strcmp(drv1->protocol_name, protocol))
247
            return drv1;
248
    }
249
    return NULL;
250
}
251

    
252
/*
253
 * Detect host devices. By convention, /dev/cdrom[N] is always
254
 * recognized as a host CDROM.
255
 */
256
static BlockDriver *find_hdev_driver(const char *filename)
257
{
258
    int score_max = 0, score;
259
    BlockDriver *drv = NULL, *d;
260

    
261
    for (d = first_drv; d; d = d->next) {
262
        if (d->bdrv_probe_device) {
263
            score = d->bdrv_probe_device(filename);
264
            if (score > score_max) {
265
                score_max = score;
266
                drv = d;
267
            }
268
        }
269
    }
270

    
271
    return drv;
272
}
273

    
274
static BlockDriver *find_image_format(const char *filename)
275
{
276
    int ret, score, score_max;
277
    BlockDriver *drv1, *drv;
278
    uint8_t buf[2048];
279
    BlockDriverState *bs;
280

    
281
    drv = find_protocol(filename);
282
    /* no need to test disk image formats for vvfat */
283
    if (drv && strcmp(drv->format_name, "vvfat") == 0)
284
        return drv;
285

    
286
    ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
287
    if (ret < 0)
288
        return NULL;
289
    ret = bdrv_pread(bs, 0, buf, sizeof(buf));
290
    bdrv_delete(bs);
291
    if (ret < 0) {
292
        return NULL;
293
    }
294

    
295
    score_max = 0;
296
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
297
        if (drv1->bdrv_probe) {
298
            score = drv1->bdrv_probe(buf, ret, filename);
299
            if (score > score_max) {
300
                score_max = score;
301
                drv = drv1;
302
            }
303
        }
304
    }
305
    return drv;
306
}
307

    
308
int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
309
{
310
    BlockDriverState *bs;
311
    int ret;
312

    
313
    bs = bdrv_new("");
314
    ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL);
315
    if (ret < 0) {
316
        bdrv_delete(bs);
317
        return ret;
318
    }
319
    bs->growable = 1;
320
    *pbs = bs;
321
    return 0;
322
}
323

    
324
int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
325
{
326
    return bdrv_open2(bs, filename, flags, NULL);
327
}
328

    
329
int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
330
               BlockDriver *drv)
331
{
332
    int ret, open_flags;
333
    char tmp_filename[PATH_MAX];
334
    char backing_filename[PATH_MAX];
335

    
336
    bs->read_only = 0;
337
    bs->is_temporary = 0;
338
    bs->encrypted = 0;
339
    bs->valid_key = 0;
340
    /* buffer_alignment defaulted to 512, drivers can change this value */
341
    bs->buffer_alignment = 512;
342

    
343
    if (flags & BDRV_O_SNAPSHOT) {
344
        BlockDriverState *bs1;
345
        int64_t total_size;
346
        int is_protocol = 0;
347
        BlockDriver *bdrv_qcow2;
348
        QEMUOptionParameter *options;
349

    
350
        /* if snapshot, we create a temporary backing file and open it
351
           instead of opening 'filename' directly */
352

    
353
        /* if there is a backing file, use it */
354
        bs1 = bdrv_new("");
355
        ret = bdrv_open2(bs1, filename, 0, drv);
356
        if (ret < 0) {
357
            bdrv_delete(bs1);
358
            return ret;
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
        bdrv_qcow2 = bdrv_find_format("qcow2");
377
        options = parse_option_parameters("", bdrv_qcow2->create_options, NULL);
378

    
379
        set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size * 512);
380
        set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename);
381
        if (drv) {
382
            set_option_parameter(options, BLOCK_OPT_BACKING_FMT,
383
                drv->format_name);
384
        }
385

    
386
        ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
387
        if (ret < 0) {
388
            return ret;
389
        }
390

    
391
        filename = tmp_filename;
392
        drv = bdrv_qcow2;
393
        bs->is_temporary = 1;
394
    }
395

    
396
    pstrcpy(bs->filename, sizeof(bs->filename), filename);
397
    if (flags & BDRV_O_FILE) {
398
        drv = find_protocol(filename);
399
    } else if (!drv) {
400
        drv = find_hdev_driver(filename);
401
        if (!drv) {
402
            drv = find_image_format(filename);
403
        }
404
    }
405
    if (!drv) {
406
        ret = -ENOENT;
407
        goto unlink_and_fail;
408
    }
409
    bs->drv = drv;
410
    bs->opaque = qemu_mallocz(drv->instance_size);
411
    /* Note: for compatibility, we open disk image files as RDWR, and
412
       RDONLY as fallback */
413
    if (!(flags & BDRV_O_FILE))
414
        open_flags = BDRV_O_RDWR | (flags & BDRV_O_CACHE_MASK);
415
    else
416
        open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
417
    ret = drv->bdrv_open(bs, filename, open_flags);
418
    if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) {
419
        ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR);
420
        bs->read_only = 1;
421
    }
422
    if (ret < 0) {
423
        qemu_free(bs->opaque);
424
        bs->opaque = NULL;
425
        bs->drv = NULL;
426
    unlink_and_fail:
427
        if (bs->is_temporary)
428
            unlink(filename);
429
        return ret;
430
    }
431
    if (drv->bdrv_getlength) {
432
        bs->total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
433
    }
434
#ifndef _WIN32
435
    if (bs->is_temporary) {
436
        unlink(filename);
437
    }
438
#endif
439
    if (bs->backing_file[0] != '\0') {
440
        /* if there is a backing file, use it */
441
        BlockDriver *back_drv = NULL;
442
        bs->backing_hd = bdrv_new("");
443
        path_combine(backing_filename, sizeof(backing_filename),
444
                     filename, bs->backing_file);
445
        if (bs->backing_format[0] != '\0')
446
            back_drv = bdrv_find_format(bs->backing_format);
447
        ret = bdrv_open2(bs->backing_hd, backing_filename, open_flags,
448
                         back_drv);
449
        if (ret < 0) {
450
            bdrv_close(bs);
451
            return ret;
452
        }
453
    }
454

    
455
    if (!bdrv_key_required(bs)) {
456
        /* call the change callback */
457
        bs->media_changed = 1;
458
        if (bs->change_cb)
459
            bs->change_cb(bs->change_opaque);
460
    }
461
    return 0;
462
}
463

    
464
void bdrv_close(BlockDriverState *bs)
465
{
466
    if (bs->drv) {
467
        if (bs->backing_hd)
468
            bdrv_delete(bs->backing_hd);
469
        bs->drv->bdrv_close(bs);
470
        qemu_free(bs->opaque);
471
#ifdef _WIN32
472
        if (bs->is_temporary) {
473
            unlink(bs->filename);
474
        }
475
#endif
476
        bs->opaque = NULL;
477
        bs->drv = NULL;
478

    
479
        /* call the change callback */
480
        bs->media_changed = 1;
481
        if (bs->change_cb)
482
            bs->change_cb(bs->change_opaque);
483
    }
484
}
485

    
486
void bdrv_delete(BlockDriverState *bs)
487
{
488
    BlockDriverState **pbs;
489

    
490
    pbs = &bdrv_first;
491
    while (*pbs != bs && *pbs != NULL)
492
        pbs = &(*pbs)->next;
493
    if (*pbs == bs)
494
        *pbs = bs->next;
495

    
496
    bdrv_close(bs);
497
    qemu_free(bs);
498
}
499

    
500
/*
501
 * Run consistency checks on an image
502
 *
503
 * Returns the number of errors or -errno when an internal error occurs
504
 */
505
int bdrv_check(BlockDriverState *bs)
506
{
507
    if (bs->drv->bdrv_check == NULL) {
508
        return -ENOTSUP;
509
    }
510

    
511
    return bs->drv->bdrv_check(bs);
512
}
513

    
514
/* commit COW file into the raw image */
515
int bdrv_commit(BlockDriverState *bs)
516
{
517
    BlockDriver *drv = bs->drv;
518
    int64_t i, total_sectors;
519
    int n, j;
520
    unsigned char sector[512];
521

    
522
    if (!drv)
523
        return -ENOMEDIUM;
524

    
525
    if (bs->read_only) {
526
        return -EACCES;
527
    }
528

    
529
    if (!bs->backing_hd) {
530
        return -ENOTSUP;
531
    }
532

    
533
    total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
534
    for (i = 0; i < total_sectors;) {
535
        if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
536
            for(j = 0; j < n; j++) {
537
                if (bdrv_read(bs, i, sector, 1) != 0) {
538
                    return -EIO;
539
                }
540

    
541
                if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
542
                    return -EIO;
543
                }
544
                i++;
545
            }
546
        } else {
547
            i += n;
548
        }
549
    }
550

    
551
    if (drv->bdrv_make_empty)
552
        return drv->bdrv_make_empty(bs);
553

    
554
    return 0;
555
}
556

    
557
static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
558
                                   size_t size)
559
{
560
    int64_t len;
561

    
562
    if (!bdrv_is_inserted(bs))
563
        return -ENOMEDIUM;
564

    
565
    if (bs->growable)
566
        return 0;
567

    
568
    len = bdrv_getlength(bs);
569

    
570
    if (offset < 0)
571
        return -EIO;
572

    
573
    if ((offset > len) || (len - offset < size))
574
        return -EIO;
575

    
576
    return 0;
577
}
578

    
579
static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
580
                              int nb_sectors)
581
{
582
    return bdrv_check_byte_request(bs, sector_num * 512, nb_sectors * 512);
583
}
584

    
585
/* return < 0 if error. See bdrv_write() for the return codes */
586
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
587
              uint8_t *buf, int nb_sectors)
588
{
589
    BlockDriver *drv = bs->drv;
590

    
591
    if (!drv)
592
        return -ENOMEDIUM;
593
    if (bdrv_check_request(bs, sector_num, nb_sectors))
594
        return -EIO;
595

    
596
    return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
597
}
598

    
599
/* Return < 0 if error. Important errors are:
600
  -EIO         generic I/O error (may happen for all errors)
601
  -ENOMEDIUM   No media inserted.
602
  -EINVAL      Invalid sector number or nb_sectors
603
  -EACCES      Trying to write a read-only device
604
*/
605
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
606
               const uint8_t *buf, int nb_sectors)
607
{
608
    BlockDriver *drv = bs->drv;
609
    if (!bs->drv)
610
        return -ENOMEDIUM;
611
    if (bs->read_only)
612
        return -EACCES;
613
    if (bdrv_check_request(bs, sector_num, nb_sectors))
614
        return -EIO;
615

    
616
    return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
617
}
618

    
619
int bdrv_pread(BlockDriverState *bs, int64_t offset,
620
               void *buf, int count1)
621
{
622
    uint8_t tmp_buf[SECTOR_SIZE];
623
    int len, nb_sectors, count;
624
    int64_t sector_num;
625

    
626
    count = count1;
627
    /* first read to align to sector start */
628
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
629
    if (len > count)
630
        len = count;
631
    sector_num = offset >> SECTOR_BITS;
632
    if (len > 0) {
633
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
634
            return -EIO;
635
        memcpy(buf, tmp_buf + (offset & (SECTOR_SIZE - 1)), len);
636
        count -= len;
637
        if (count == 0)
638
            return count1;
639
        sector_num++;
640
        buf += len;
641
    }
642

    
643
    /* read the sectors "in place" */
644
    nb_sectors = count >> SECTOR_BITS;
645
    if (nb_sectors > 0) {
646
        if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0)
647
            return -EIO;
648
        sector_num += nb_sectors;
649
        len = nb_sectors << SECTOR_BITS;
650
        buf += len;
651
        count -= len;
652
    }
653

    
654
    /* add data from the last sector */
655
    if (count > 0) {
656
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
657
            return -EIO;
658
        memcpy(buf, tmp_buf, count);
659
    }
660
    return count1;
661
}
662

    
663
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
664
                const void *buf, int count1)
665
{
666
    uint8_t tmp_buf[SECTOR_SIZE];
667
    int len, nb_sectors, count;
668
    int64_t sector_num;
669

    
670
    count = count1;
671
    /* first write to align to sector start */
672
    len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
673
    if (len > count)
674
        len = count;
675
    sector_num = offset >> SECTOR_BITS;
676
    if (len > 0) {
677
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
678
            return -EIO;
679
        memcpy(tmp_buf + (offset & (SECTOR_SIZE - 1)), buf, len);
680
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
681
            return -EIO;
682
        count -= len;
683
        if (count == 0)
684
            return count1;
685
        sector_num++;
686
        buf += len;
687
    }
688

    
689
    /* write the sectors "in place" */
690
    nb_sectors = count >> SECTOR_BITS;
691
    if (nb_sectors > 0) {
692
        if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
693
            return -EIO;
694
        sector_num += nb_sectors;
695
        len = nb_sectors << SECTOR_BITS;
696
        buf += len;
697
        count -= len;
698
    }
699

    
700
    /* add data from the last sector */
701
    if (count > 0) {
702
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
703
            return -EIO;
704
        memcpy(tmp_buf, buf, count);
705
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
706
            return -EIO;
707
    }
708
    return count1;
709
}
710

    
711
/**
712
 * Truncate file to 'offset' bytes (needed only for file protocols)
713
 */
714
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
715
{
716
    BlockDriver *drv = bs->drv;
717
    if (!drv)
718
        return -ENOMEDIUM;
719
    if (!drv->bdrv_truncate)
720
        return -ENOTSUP;
721
    return drv->bdrv_truncate(bs, offset);
722
}
723

    
724
/**
725
 * Length of a file in bytes. Return < 0 if error or unknown.
726
 */
727
int64_t bdrv_getlength(BlockDriverState *bs)
728
{
729
    BlockDriver *drv = bs->drv;
730
    if (!drv)
731
        return -ENOMEDIUM;
732
    if (!drv->bdrv_getlength) {
733
        /* legacy mode */
734
        return bs->total_sectors * SECTOR_SIZE;
735
    }
736
    return drv->bdrv_getlength(bs);
737
}
738

    
739
/* return 0 as number of sectors if no device present or error */
740
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
741
{
742
    int64_t length;
743
    length = bdrv_getlength(bs);
744
    if (length < 0)
745
        length = 0;
746
    else
747
        length = length >> SECTOR_BITS;
748
    *nb_sectors_ptr = length;
749
}
750

    
751
struct partition {
752
        uint8_t boot_ind;           /* 0x80 - active */
753
        uint8_t head;               /* starting head */
754
        uint8_t sector;             /* starting sector */
755
        uint8_t cyl;                /* starting cylinder */
756
        uint8_t sys_ind;            /* What partition type */
757
        uint8_t end_head;           /* end head */
758
        uint8_t end_sector;         /* end sector */
759
        uint8_t end_cyl;            /* end cylinder */
760
        uint32_t start_sect;        /* starting sector counting from 0 */
761
        uint32_t nr_sects;          /* nr of sectors in partition */
762
} __attribute__((packed));
763

    
764
/* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
765
static int guess_disk_lchs(BlockDriverState *bs,
766
                           int *pcylinders, int *pheads, int *psectors)
767
{
768
    uint8_t buf[512];
769
    int ret, i, heads, sectors, cylinders;
770
    struct partition *p;
771
    uint32_t nr_sects;
772
    uint64_t nb_sectors;
773

    
774
    bdrv_get_geometry(bs, &nb_sectors);
775

    
776
    ret = bdrv_read(bs, 0, buf, 1);
777
    if (ret < 0)
778
        return -1;
779
    /* test msdos magic */
780
    if (buf[510] != 0x55 || buf[511] != 0xaa)
781
        return -1;
782
    for(i = 0; i < 4; i++) {
783
        p = ((struct partition *)(buf + 0x1be)) + i;
784
        nr_sects = le32_to_cpu(p->nr_sects);
785
        if (nr_sects && p->end_head) {
786
            /* We make the assumption that the partition terminates on
787
               a cylinder boundary */
788
            heads = p->end_head + 1;
789
            sectors = p->end_sector & 63;
790
            if (sectors == 0)
791
                continue;
792
            cylinders = nb_sectors / (heads * sectors);
793
            if (cylinders < 1 || cylinders > 16383)
794
                continue;
795
            *pheads = heads;
796
            *psectors = sectors;
797
            *pcylinders = cylinders;
798
#if 0
799
            printf("guessed geometry: LCHS=%d %d %d\n",
800
                   cylinders, heads, sectors);
801
#endif
802
            return 0;
803
        }
804
    }
805
    return -1;
806
}
807

    
808
void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
809
{
810
    int translation, lba_detected = 0;
811
    int cylinders, heads, secs;
812
    uint64_t nb_sectors;
813

    
814
    /* if a geometry hint is available, use it */
815
    bdrv_get_geometry(bs, &nb_sectors);
816
    bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
817
    translation = bdrv_get_translation_hint(bs);
818
    if (cylinders != 0) {
819
        *pcyls = cylinders;
820
        *pheads = heads;
821
        *psecs = secs;
822
    } else {
823
        if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
824
            if (heads > 16) {
825
                /* if heads > 16, it means that a BIOS LBA
826
                   translation was active, so the default
827
                   hardware geometry is OK */
828
                lba_detected = 1;
829
                goto default_geometry;
830
            } else {
831
                *pcyls = cylinders;
832
                *pheads = heads;
833
                *psecs = secs;
834
                /* disable any translation to be in sync with
835
                   the logical geometry */
836
                if (translation == BIOS_ATA_TRANSLATION_AUTO) {
837
                    bdrv_set_translation_hint(bs,
838
                                              BIOS_ATA_TRANSLATION_NONE);
839
                }
840
            }
841
        } else {
842
        default_geometry:
843
            /* if no geometry, use a standard physical disk geometry */
844
            cylinders = nb_sectors / (16 * 63);
845

    
846
            if (cylinders > 16383)
847
                cylinders = 16383;
848
            else if (cylinders < 2)
849
                cylinders = 2;
850
            *pcyls = cylinders;
851
            *pheads = 16;
852
            *psecs = 63;
853
            if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
854
                if ((*pcyls * *pheads) <= 131072) {
855
                    bdrv_set_translation_hint(bs,
856
                                              BIOS_ATA_TRANSLATION_LARGE);
857
                } else {
858
                    bdrv_set_translation_hint(bs,
859
                                              BIOS_ATA_TRANSLATION_LBA);
860
                }
861
            }
862
        }
863
        bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
864
    }
865
}
866

    
867
void bdrv_set_geometry_hint(BlockDriverState *bs,
868
                            int cyls, int heads, int secs)
869
{
870
    bs->cyls = cyls;
871
    bs->heads = heads;
872
    bs->secs = secs;
873
}
874

    
875
void bdrv_set_type_hint(BlockDriverState *bs, int type)
876
{
877
    bs->type = type;
878
    bs->removable = ((type == BDRV_TYPE_CDROM ||
879
                      type == BDRV_TYPE_FLOPPY));
880
}
881

    
882
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
883
{
884
    bs->translation = translation;
885
}
886

    
887
void bdrv_get_geometry_hint(BlockDriverState *bs,
888
                            int *pcyls, int *pheads, int *psecs)
889
{
890
    *pcyls = bs->cyls;
891
    *pheads = bs->heads;
892
    *psecs = bs->secs;
893
}
894

    
895
int bdrv_get_type_hint(BlockDriverState *bs)
896
{
897
    return bs->type;
898
}
899

    
900
int bdrv_get_translation_hint(BlockDriverState *bs)
901
{
902
    return bs->translation;
903
}
904

    
905
int bdrv_is_removable(BlockDriverState *bs)
906
{
907
    return bs->removable;
908
}
909

    
910
int bdrv_is_read_only(BlockDriverState *bs)
911
{
912
    return bs->read_only;
913
}
914

    
915
int bdrv_is_sg(BlockDriverState *bs)
916
{
917
    return bs->sg;
918
}
919

    
920
/* XXX: no longer used */
921
void bdrv_set_change_cb(BlockDriverState *bs,
922
                        void (*change_cb)(void *opaque), void *opaque)
923
{
924
    bs->change_cb = change_cb;
925
    bs->change_opaque = opaque;
926
}
927

    
928
int bdrv_is_encrypted(BlockDriverState *bs)
929
{
930
    if (bs->backing_hd && bs->backing_hd->encrypted)
931
        return 1;
932
    return bs->encrypted;
933
}
934

    
935
int bdrv_key_required(BlockDriverState *bs)
936
{
937
    BlockDriverState *backing_hd = bs->backing_hd;
938

    
939
    if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
940
        return 1;
941
    return (bs->encrypted && !bs->valid_key);
942
}
943

    
944
int bdrv_set_key(BlockDriverState *bs, const char *key)
945
{
946
    int ret;
947
    if (bs->backing_hd && bs->backing_hd->encrypted) {
948
        ret = bdrv_set_key(bs->backing_hd, key);
949
        if (ret < 0)
950
            return ret;
951
        if (!bs->encrypted)
952
            return 0;
953
    }
954
    if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
955
        return -1;
956
    ret = bs->drv->bdrv_set_key(bs, key);
957
    if (ret < 0) {
958
        bs->valid_key = 0;
959
    } else if (!bs->valid_key) {
960
        bs->valid_key = 1;
961
        /* call the change callback now, we skipped it on open */
962
        bs->media_changed = 1;
963
        if (bs->change_cb)
964
            bs->change_cb(bs->change_opaque);
965
    }
966
    return ret;
967
}
968

    
969
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
970
{
971
    if (!bs->drv) {
972
        buf[0] = '\0';
973
    } else {
974
        pstrcpy(buf, buf_size, bs->drv->format_name);
975
    }
976
}
977

    
978
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
979
                         void *opaque)
980
{
981
    BlockDriver *drv;
982

    
983
    for (drv = first_drv; drv != NULL; drv = drv->next) {
984
        it(opaque, drv->format_name);
985
    }
986
}
987

    
988
BlockDriverState *bdrv_find(const char *name)
989
{
990
    BlockDriverState *bs;
991

    
992
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
993
        if (!strcmp(name, bs->device_name))
994
            return bs;
995
    }
996
    return NULL;
997
}
998

    
999
void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
1000
{
1001
    BlockDriverState *bs;
1002

    
1003
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1004
        it(opaque, bs);
1005
    }
1006
}
1007

    
1008
const char *bdrv_get_device_name(BlockDriverState *bs)
1009
{
1010
    return bs->device_name;
1011
}
1012

    
1013
void bdrv_flush(BlockDriverState *bs)
1014
{
1015
    if (!bs->drv)
1016
        return;
1017
    if (bs->drv->bdrv_flush)
1018
        bs->drv->bdrv_flush(bs);
1019
    if (bs->backing_hd)
1020
        bdrv_flush(bs->backing_hd);
1021
}
1022

    
1023
void bdrv_flush_all(void)
1024
{
1025
    BlockDriverState *bs;
1026

    
1027
    for (bs = bdrv_first; bs != NULL; bs = bs->next)
1028
        if (bs->drv && !bdrv_is_read_only(bs) && 
1029
            (!bdrv_is_removable(bs) || bdrv_is_inserted(bs)))
1030
            bdrv_flush(bs);
1031
}
1032

    
1033
/*
1034
 * Returns true iff the specified sector is present in the disk image. Drivers
1035
 * not implementing the functionality are assumed to not support backing files,
1036
 * hence all their sectors are reported as allocated.
1037
 *
1038
 * 'pnum' is set to the number of sectors (including and immediately following
1039
 * the specified sector) that are known to be in the same
1040
 * allocated/unallocated state.
1041
 *
1042
 * 'nb_sectors' is the max value 'pnum' should be set to.
1043
 */
1044
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
1045
        int *pnum)
1046
{
1047
    int64_t n;
1048
    if (!bs->drv->bdrv_is_allocated) {
1049
        if (sector_num >= bs->total_sectors) {
1050
            *pnum = 0;
1051
            return 0;
1052
        }
1053
        n = bs->total_sectors - sector_num;
1054
        *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
1055
        return 1;
1056
    }
1057
    return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
1058
}
1059

    
1060
void bdrv_info(Monitor *mon)
1061
{
1062
    BlockDriverState *bs;
1063

    
1064
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1065
        monitor_printf(mon, "%s:", bs->device_name);
1066
        monitor_printf(mon, " type=");
1067
        switch(bs->type) {
1068
        case BDRV_TYPE_HD:
1069
            monitor_printf(mon, "hd");
1070
            break;
1071
        case BDRV_TYPE_CDROM:
1072
            monitor_printf(mon, "cdrom");
1073
            break;
1074
        case BDRV_TYPE_FLOPPY:
1075
            monitor_printf(mon, "floppy");
1076
            break;
1077
        }
1078
        monitor_printf(mon, " removable=%d", bs->removable);
1079
        if (bs->removable) {
1080
            monitor_printf(mon, " locked=%d", bs->locked);
1081
        }
1082
        if (bs->drv) {
1083
            monitor_printf(mon, " file=");
1084
            monitor_print_filename(mon, bs->filename);
1085
            if (bs->backing_file[0] != '\0') {
1086
                monitor_printf(mon, " backing_file=");
1087
                monitor_print_filename(mon, bs->backing_file);
1088
            }
1089
            monitor_printf(mon, " ro=%d", bs->read_only);
1090
            monitor_printf(mon, " drv=%s", bs->drv->format_name);
1091
            monitor_printf(mon, " encrypted=%d", bdrv_is_encrypted(bs));
1092
        } else {
1093
            monitor_printf(mon, " [not inserted]");
1094
        }
1095
        monitor_printf(mon, "\n");
1096
    }
1097
}
1098

    
1099
/* The "info blockstats" command. */
1100
void bdrv_info_stats(Monitor *mon)
1101
{
1102
    BlockDriverState *bs;
1103

    
1104
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1105
        monitor_printf(mon, "%s:"
1106
                       " rd_bytes=%" PRIu64
1107
                       " wr_bytes=%" PRIu64
1108
                       " rd_operations=%" PRIu64
1109
                       " wr_operations=%" PRIu64
1110
                       "\n",
1111
                       bs->device_name,
1112
                       bs->rd_bytes, bs->wr_bytes,
1113
                       bs->rd_ops, bs->wr_ops);
1114
    }
1115
}
1116

    
1117
const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
1118
{
1119
    if (bs->backing_hd && bs->backing_hd->encrypted)
1120
        return bs->backing_file;
1121
    else if (bs->encrypted)
1122
        return bs->filename;
1123
    else
1124
        return NULL;
1125
}
1126

    
1127
void bdrv_get_backing_filename(BlockDriverState *bs,
1128
                               char *filename, int filename_size)
1129
{
1130
    if (!bs->backing_hd) {
1131
        pstrcpy(filename, filename_size, "");
1132
    } else {
1133
        pstrcpy(filename, filename_size, bs->backing_file);
1134
    }
1135
}
1136

    
1137
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
1138
                          const uint8_t *buf, int nb_sectors)
1139
{
1140
    BlockDriver *drv = bs->drv;
1141
    if (!drv)
1142
        return -ENOMEDIUM;
1143
    if (!drv->bdrv_write_compressed)
1144
        return -ENOTSUP;
1145
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1146
        return -EIO;
1147
    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
1148
}
1149

    
1150
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1151
{
1152
    BlockDriver *drv = bs->drv;
1153
    if (!drv)
1154
        return -ENOMEDIUM;
1155
    if (!drv->bdrv_get_info)
1156
        return -ENOTSUP;
1157
    memset(bdi, 0, sizeof(*bdi));
1158
    return drv->bdrv_get_info(bs, bdi);
1159
}
1160

    
1161
int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
1162
                      int64_t pos, int size)
1163
{
1164
    BlockDriver *drv = bs->drv;
1165
    if (!drv)
1166
        return -ENOMEDIUM;
1167
    if (!drv->bdrv_save_vmstate)
1168
        return -ENOTSUP;
1169
    return drv->bdrv_save_vmstate(bs, buf, pos, size);
1170
}
1171

    
1172
int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
1173
                      int64_t pos, int size)
1174
{
1175
    BlockDriver *drv = bs->drv;
1176
    if (!drv)
1177
        return -ENOMEDIUM;
1178
    if (!drv->bdrv_load_vmstate)
1179
        return -ENOTSUP;
1180
    return drv->bdrv_load_vmstate(bs, buf, pos, size);
1181
}
1182

    
1183
/**************************************************************/
1184
/* handling of snapshots */
1185

    
1186
int bdrv_snapshot_create(BlockDriverState *bs,
1187
                         QEMUSnapshotInfo *sn_info)
1188
{
1189
    BlockDriver *drv = bs->drv;
1190
    if (!drv)
1191
        return -ENOMEDIUM;
1192
    if (!drv->bdrv_snapshot_create)
1193
        return -ENOTSUP;
1194
    return drv->bdrv_snapshot_create(bs, sn_info);
1195
}
1196

    
1197
int bdrv_snapshot_goto(BlockDriverState *bs,
1198
                       const char *snapshot_id)
1199
{
1200
    BlockDriver *drv = bs->drv;
1201
    if (!drv)
1202
        return -ENOMEDIUM;
1203
    if (!drv->bdrv_snapshot_goto)
1204
        return -ENOTSUP;
1205
    return drv->bdrv_snapshot_goto(bs, snapshot_id);
1206
}
1207

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

    
1218
int bdrv_snapshot_list(BlockDriverState *bs,
1219
                       QEMUSnapshotInfo **psn_info)
1220
{
1221
    BlockDriver *drv = bs->drv;
1222
    if (!drv)
1223
        return -ENOMEDIUM;
1224
    if (!drv->bdrv_snapshot_list)
1225
        return -ENOTSUP;
1226
    return drv->bdrv_snapshot_list(bs, psn_info);
1227
}
1228

    
1229
#define NB_SUFFIXES 4
1230

    
1231
char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1232
{
1233
    static const char suffixes[NB_SUFFIXES] = "KMGT";
1234
    int64_t base;
1235
    int i;
1236

    
1237
    if (size <= 999) {
1238
        snprintf(buf, buf_size, "%" PRId64, size);
1239
    } else {
1240
        base = 1024;
1241
        for(i = 0; i < NB_SUFFIXES; i++) {
1242
            if (size < (10 * base)) {
1243
                snprintf(buf, buf_size, "%0.1f%c",
1244
                         (double)size / base,
1245
                         suffixes[i]);
1246
                break;
1247
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1248
                snprintf(buf, buf_size, "%" PRId64 "%c",
1249
                         ((size + (base >> 1)) / base),
1250
                         suffixes[i]);
1251
                break;
1252
            }
1253
            base = base * 1024;
1254
        }
1255
    }
1256
    return buf;
1257
}
1258

    
1259
char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1260
{
1261
    char buf1[128], date_buf[128], clock_buf[128];
1262
#ifdef _WIN32
1263
    struct tm *ptm;
1264
#else
1265
    struct tm tm;
1266
#endif
1267
    time_t ti;
1268
    int64_t secs;
1269

    
1270
    if (!sn) {
1271
        snprintf(buf, buf_size,
1272
                 "%-10s%-20s%7s%20s%15s",
1273
                 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1274
    } else {
1275
        ti = sn->date_sec;
1276
#ifdef _WIN32
1277
        ptm = localtime(&ti);
1278
        strftime(date_buf, sizeof(date_buf),
1279
                 "%Y-%m-%d %H:%M:%S", ptm);
1280
#else
1281
        localtime_r(&ti, &tm);
1282
        strftime(date_buf, sizeof(date_buf),
1283
                 "%Y-%m-%d %H:%M:%S", &tm);
1284
#endif
1285
        secs = sn->vm_clock_nsec / 1000000000;
1286
        snprintf(clock_buf, sizeof(clock_buf),
1287
                 "%02d:%02d:%02d.%03d",
1288
                 (int)(secs / 3600),
1289
                 (int)((secs / 60) % 60),
1290
                 (int)(secs % 60),
1291
                 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1292
        snprintf(buf, buf_size,
1293
                 "%-10s%-20s%7s%20s%15s",
1294
                 sn->id_str, sn->name,
1295
                 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1296
                 date_buf,
1297
                 clock_buf);
1298
    }
1299
    return buf;
1300
}
1301

    
1302

    
1303
/**************************************************************/
1304
/* async I/Os */
1305

    
1306
BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
1307
                                 QEMUIOVector *qiov, int nb_sectors,
1308
                                 BlockDriverCompletionFunc *cb, void *opaque)
1309
{
1310
    BlockDriver *drv = bs->drv;
1311
    BlockDriverAIOCB *ret;
1312

    
1313
    if (!drv)
1314
        return NULL;
1315
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1316
        return NULL;
1317

    
1318
    ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
1319
                              cb, opaque);
1320

    
1321
    if (ret) {
1322
        /* Update stats even though technically transfer has not happened. */
1323
        bs->rd_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1324
        bs->rd_ops ++;
1325
    }
1326

    
1327
    return ret;
1328
}
1329

    
1330
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
1331
                                  QEMUIOVector *qiov, int nb_sectors,
1332
                                  BlockDriverCompletionFunc *cb, void *opaque)
1333
{
1334
    BlockDriver *drv = bs->drv;
1335
    BlockDriverAIOCB *ret;
1336

    
1337
    if (!drv)
1338
        return NULL;
1339
    if (bs->read_only)
1340
        return NULL;
1341
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1342
        return NULL;
1343

    
1344
    ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors,
1345
                               cb, opaque);
1346

    
1347
    if (ret) {
1348
        /* Update stats even though technically transfer has not happened. */
1349
        bs->wr_bytes += (unsigned) nb_sectors * SECTOR_SIZE;
1350
        bs->wr_ops ++;
1351
    }
1352

    
1353
    return ret;
1354
}
1355

    
1356
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1357
{
1358
    acb->pool->cancel(acb);
1359
}
1360

    
1361

    
1362
/**************************************************************/
1363
/* async block device emulation */
1364

    
1365
typedef struct BlockDriverAIOCBSync {
1366
    BlockDriverAIOCB common;
1367
    QEMUBH *bh;
1368
    int ret;
1369
    /* vector translation state */
1370
    QEMUIOVector *qiov;
1371
    uint8_t *bounce;
1372
    int is_write;
1373
} BlockDriverAIOCBSync;
1374

    
1375
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1376
{
1377
    BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1378
    qemu_bh_delete(acb->bh);
1379
    acb->bh = NULL;
1380
    qemu_aio_release(acb);
1381
}
1382

    
1383
static AIOPool bdrv_em_aio_pool = {
1384
    .aiocb_size         = sizeof(BlockDriverAIOCBSync),
1385
    .cancel             = bdrv_aio_cancel_em,
1386
};
1387

    
1388
static void bdrv_aio_bh_cb(void *opaque)
1389
{
1390
    BlockDriverAIOCBSync *acb = opaque;
1391

    
1392
    if (!acb->is_write)
1393
        qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size);
1394
    qemu_vfree(acb->bounce);
1395
    acb->common.cb(acb->common.opaque, acb->ret);
1396
    qemu_bh_delete(acb->bh);
1397
    acb->bh = NULL;
1398
    qemu_aio_release(acb);
1399
}
1400

    
1401
static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
1402
                                            int64_t sector_num,
1403
                                            QEMUIOVector *qiov,
1404
                                            int nb_sectors,
1405
                                            BlockDriverCompletionFunc *cb,
1406
                                            void *opaque,
1407
                                            int is_write)
1408

    
1409
{
1410
    BlockDriverAIOCBSync *acb;
1411

    
1412
    acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
1413
    acb->is_write = is_write;
1414
    acb->qiov = qiov;
1415
    acb->bounce = qemu_blockalign(bs, qiov->size);
1416

    
1417
    if (!acb->bh)
1418
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1419

    
1420
    if (is_write) {
1421
        qemu_iovec_to_buffer(acb->qiov, acb->bounce);
1422
        acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
1423
    } else {
1424
        acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
1425
    }
1426

    
1427
    qemu_bh_schedule(acb->bh);
1428

    
1429
    return &acb->common;
1430
}
1431

    
1432
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
1433
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
1434
        BlockDriverCompletionFunc *cb, void *opaque)
1435
{
1436
    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
1437
}
1438

    
1439
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
1440
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
1441
        BlockDriverCompletionFunc *cb, void *opaque)
1442
{
1443
    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
1444
}
1445

    
1446
/**************************************************************/
1447
/* sync block device emulation */
1448

    
1449
static void bdrv_rw_em_cb(void *opaque, int ret)
1450
{
1451
    *(int *)opaque = ret;
1452
}
1453

    
1454
#define NOT_DONE 0x7fffffff
1455

    
1456
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1457
                        uint8_t *buf, int nb_sectors)
1458
{
1459
    int async_ret;
1460
    BlockDriverAIOCB *acb;
1461
    struct iovec iov;
1462
    QEMUIOVector qiov;
1463

    
1464
    async_ret = NOT_DONE;
1465
    iov.iov_base = (void *)buf;
1466
    iov.iov_len = nb_sectors * 512;
1467
    qemu_iovec_init_external(&qiov, &iov, 1);
1468
    acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors,
1469
        bdrv_rw_em_cb, &async_ret);
1470
    if (acb == NULL)
1471
        return -1;
1472

    
1473
    while (async_ret == NOT_DONE) {
1474
        qemu_aio_wait();
1475
    }
1476

    
1477
    return async_ret;
1478
}
1479

    
1480
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1481
                         const uint8_t *buf, int nb_sectors)
1482
{
1483
    int async_ret;
1484
    BlockDriverAIOCB *acb;
1485
    struct iovec iov;
1486
    QEMUIOVector qiov;
1487

    
1488
    async_ret = NOT_DONE;
1489
    iov.iov_base = (void *)buf;
1490
    iov.iov_len = nb_sectors * 512;
1491
    qemu_iovec_init_external(&qiov, &iov, 1);
1492
    acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors,
1493
        bdrv_rw_em_cb, &async_ret);
1494
    if (acb == NULL)
1495
        return -1;
1496
    while (async_ret == NOT_DONE) {
1497
        qemu_aio_wait();
1498
    }
1499
    return async_ret;
1500
}
1501

    
1502
void bdrv_init(void)
1503
{
1504
    module_call_init(MODULE_INIT_BLOCK);
1505
}
1506

    
1507
void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
1508
                   BlockDriverCompletionFunc *cb, void *opaque)
1509
{
1510
    BlockDriverAIOCB *acb;
1511

    
1512
    if (pool->free_aiocb) {
1513
        acb = pool->free_aiocb;
1514
        pool->free_aiocb = acb->next;
1515
    } else {
1516
        acb = qemu_mallocz(pool->aiocb_size);
1517
        acb->pool = pool;
1518
    }
1519
    acb->bs = bs;
1520
    acb->cb = cb;
1521
    acb->opaque = opaque;
1522
    return acb;
1523
}
1524

    
1525
void qemu_aio_release(void *p)
1526
{
1527
    BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p;
1528
    AIOPool *pool = acb->pool;
1529
    acb->next = pool->free_aiocb;
1530
    pool->free_aiocb = acb;
1531
}
1532

    
1533
/**************************************************************/
1534
/* removable device support */
1535

    
1536
/**
1537
 * Return TRUE if the media is present
1538
 */
1539
int bdrv_is_inserted(BlockDriverState *bs)
1540
{
1541
    BlockDriver *drv = bs->drv;
1542
    int ret;
1543
    if (!drv)
1544
        return 0;
1545
    if (!drv->bdrv_is_inserted)
1546
        return 1;
1547
    ret = drv->bdrv_is_inserted(bs);
1548
    return ret;
1549
}
1550

    
1551
/**
1552
 * Return TRUE if the media changed since the last call to this
1553
 * function. It is currently only used for floppy disks
1554
 */
1555
int bdrv_media_changed(BlockDriverState *bs)
1556
{
1557
    BlockDriver *drv = bs->drv;
1558
    int ret;
1559

    
1560
    if (!drv || !drv->bdrv_media_changed)
1561
        ret = -ENOTSUP;
1562
    else
1563
        ret = drv->bdrv_media_changed(bs);
1564
    if (ret == -ENOTSUP)
1565
        ret = bs->media_changed;
1566
    bs->media_changed = 0;
1567
    return ret;
1568
}
1569

    
1570
/**
1571
 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
1572
 */
1573
int bdrv_eject(BlockDriverState *bs, int eject_flag)
1574
{
1575
    BlockDriver *drv = bs->drv;
1576
    int ret;
1577

    
1578
    if (bs->locked) {
1579
        return -EBUSY;
1580
    }
1581

    
1582
    if (!drv || !drv->bdrv_eject) {
1583
        ret = -ENOTSUP;
1584
    } else {
1585
        ret = drv->bdrv_eject(bs, eject_flag);
1586
    }
1587
    if (ret == -ENOTSUP) {
1588
        if (eject_flag)
1589
            bdrv_close(bs);
1590
        ret = 0;
1591
    }
1592

    
1593
    return ret;
1594
}
1595

    
1596
int bdrv_is_locked(BlockDriverState *bs)
1597
{
1598
    return bs->locked;
1599
}
1600

    
1601
/**
1602
 * Lock or unlock the media (if it is locked, the user won't be able
1603
 * to eject it manually).
1604
 */
1605
void bdrv_set_locked(BlockDriverState *bs, int locked)
1606
{
1607
    BlockDriver *drv = bs->drv;
1608

    
1609
    bs->locked = locked;
1610
    if (drv && drv->bdrv_set_locked) {
1611
        drv->bdrv_set_locked(bs, locked);
1612
    }
1613
}
1614

    
1615
/* needed for generic scsi interface */
1616

    
1617
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
1618
{
1619
    BlockDriver *drv = bs->drv;
1620

    
1621
    if (drv && drv->bdrv_ioctl)
1622
        return drv->bdrv_ioctl(bs, req, buf);
1623
    return -ENOTSUP;
1624
}
1625

    
1626
BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
1627
        unsigned long int req, void *buf,
1628
        BlockDriverCompletionFunc *cb, void *opaque)
1629
{
1630
    BlockDriver *drv = bs->drv;
1631

    
1632
    if (drv && drv->bdrv_aio_ioctl)
1633
        return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
1634
    return NULL;
1635
}
1636

    
1637
void *qemu_blockalign(BlockDriverState *bs, size_t size)
1638
{
1639
    return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
1640
}