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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
#include "qemu-common.h"
26
#include "monitor.h"
27
#include "block_int.h"
28
#include "module.h"
29
#include "qemu-objects.h"
30

    
31
#ifdef CONFIG_BSD
32
#include <sys/types.h>
33
#include <sys/stat.h>
34
#include <sys/ioctl.h>
35
#include <sys/queue.h>
36
#ifndef __DragonFly__
37
#include <sys/disk.h>
38
#endif
39
#endif
40

    
41
#ifdef _WIN32
42
#include <windows.h>
43
#endif
44

    
45
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
46
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
47
        BlockDriverCompletionFunc *cb, void *opaque);
48
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
49
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
50
        BlockDriverCompletionFunc *cb, void *opaque);
51
static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
52
        BlockDriverCompletionFunc *cb, void *opaque);
53
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
54
                        uint8_t *buf, int nb_sectors);
55
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
56
                         const uint8_t *buf, int nb_sectors);
57

    
58
BlockDriverState *bdrv_first;
59

    
60
static BlockDriver *first_drv;
61

    
62
/* If non-zero, use only whitelisted block drivers */
63
static int use_bdrv_whitelist;
64

    
65
int path_is_absolute(const char *path)
66
{
67
    const char *p;
68
#ifdef _WIN32
69
    /* specific case for names like: "\\.\d:" */
70
    if (*path == '/' || *path == '\\')
71
        return 1;
72
#endif
73
    p = strchr(path, ':');
74
    if (p)
75
        p++;
76
    else
77
        p = path;
78
#ifdef _WIN32
79
    return (*p == '/' || *p == '\\');
80
#else
81
    return (*p == '/');
82
#endif
83
}
84

    
85
/* if filename is absolute, just copy it to dest. Otherwise, build a
86
   path to it by considering it is relative to base_path. URL are
87
   supported. */
88
void path_combine(char *dest, int dest_size,
89
                  const char *base_path,
90
                  const char *filename)
91
{
92
    const char *p, *p1;
93
    int len;
94

    
95
    if (dest_size <= 0)
96
        return;
97
    if (path_is_absolute(filename)) {
98
        pstrcpy(dest, dest_size, filename);
99
    } else {
100
        p = strchr(base_path, ':');
101
        if (p)
102
            p++;
103
        else
104
            p = base_path;
105
        p1 = strrchr(base_path, '/');
106
#ifdef _WIN32
107
        {
108
            const char *p2;
109
            p2 = strrchr(base_path, '\\');
110
            if (!p1 || p2 > p1)
111
                p1 = p2;
112
        }
113
#endif
114
        if (p1)
115
            p1++;
116
        else
117
            p1 = base_path;
118
        if (p1 > p)
119
            p = p1;
120
        len = p - base_path;
121
        if (len > dest_size - 1)
122
            len = dest_size - 1;
123
        memcpy(dest, base_path, len);
124
        dest[len] = '\0';
125
        pstrcat(dest, dest_size, filename);
126
    }
127
}
128

    
129
void bdrv_register(BlockDriver *bdrv)
130
{
131
    if (!bdrv->bdrv_aio_readv) {
132
        /* add AIO emulation layer */
133
        bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
134
        bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
135
    } else if (!bdrv->bdrv_read) {
136
        /* add synchronous IO emulation layer */
137
        bdrv->bdrv_read = bdrv_read_em;
138
        bdrv->bdrv_write = bdrv_write_em;
139
    }
140

    
141
    if (!bdrv->bdrv_aio_flush)
142
        bdrv->bdrv_aio_flush = bdrv_aio_flush_em;
143

    
144
    bdrv->next = first_drv;
145
    first_drv = bdrv;
146
}
147

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

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

    
165
BlockDriver *bdrv_find_format(const char *format_name)
166
{
167
    BlockDriver *drv1;
168
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
169
        if (!strcmp(drv1->format_name, format_name))
170
            return drv1;
171
    }
172
    return NULL;
173
}
174

    
175
static int bdrv_is_whitelisted(BlockDriver *drv)
176
{
177
    static const char *whitelist[] = {
178
        CONFIG_BDRV_WHITELIST
179
    };
180
    const char **p;
181

    
182
    if (!whitelist[0])
183
        return 1;               /* no whitelist, anything goes */
184

    
185
    for (p = whitelist; *p; p++) {
186
        if (!strcmp(drv->format_name, *p)) {
187
            return 1;
188
        }
189
    }
190
    return 0;
191
}
192

    
193
BlockDriver *bdrv_find_whitelisted_format(const char *format_name)
194
{
195
    BlockDriver *drv = bdrv_find_format(format_name);
196
    return drv && bdrv_is_whitelisted(drv) ? drv : NULL;
197
}
198

    
199
int bdrv_create(BlockDriver *drv, const char* filename,
200
    QEMUOptionParameter *options)
201
{
202
    if (!drv->bdrv_create)
203
        return -ENOTSUP;
204

    
205
    return drv->bdrv_create(filename, options);
206
}
207

    
208
#ifdef _WIN32
209
void get_tmp_filename(char *filename, int size)
210
{
211
    char temp_dir[MAX_PATH];
212

    
213
    GetTempPath(MAX_PATH, temp_dir);
214
    GetTempFileName(temp_dir, "qem", 0, filename);
215
}
216
#else
217
void get_tmp_filename(char *filename, int size)
218
{
219
    int fd;
220
    const char *tmpdir;
221
    /* XXX: race condition possible */
222
    tmpdir = getenv("TMPDIR");
223
    if (!tmpdir)
224
        tmpdir = "/tmp";
225
    snprintf(filename, size, "%s/vl.XXXXXX", tmpdir);
226
    fd = mkstemp(filename);
227
    close(fd);
228
}
229
#endif
230

    
231
#ifdef _WIN32
232
static int is_windows_drive_prefix(const char *filename)
233
{
234
    return (((filename[0] >= 'a' && filename[0] <= 'z') ||
235
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
236
            filename[1] == ':');
237
}
238

    
239
int is_windows_drive(const char *filename)
240
{
241
    if (is_windows_drive_prefix(filename) &&
242
        filename[2] == '\0')
243
        return 1;
244
    if (strstart(filename, "\\\\.\\", NULL) ||
245
        strstart(filename, "//./", NULL))
246
        return 1;
247
    return 0;
248
}
249
#endif
250

    
251
static BlockDriver *find_protocol(const char *filename)
252
{
253
    BlockDriver *drv1;
254
    char protocol[128];
255
    int len;
256
    const char *p;
257

    
258
#ifdef _WIN32
259
    if (is_windows_drive(filename) ||
260
        is_windows_drive_prefix(filename))
261
        return bdrv_find_format("raw");
262
#endif
263
    p = strchr(filename, ':');
264
    if (!p)
265
        return bdrv_find_format("raw");
266
    len = p - filename;
267
    if (len > sizeof(protocol) - 1)
268
        len = sizeof(protocol) - 1;
269
    memcpy(protocol, filename, len);
270
    protocol[len] = '\0';
271
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
272
        if (drv1->protocol_name &&
273
            !strcmp(drv1->protocol_name, protocol))
274
            return drv1;
275
    }
276
    return NULL;
277
}
278

    
279
/*
280
 * Detect host devices. By convention, /dev/cdrom[N] is always
281
 * recognized as a host CDROM.
282
 */
283
static BlockDriver *find_hdev_driver(const char *filename)
284
{
285
    int score_max = 0, score;
286
    BlockDriver *drv = NULL, *d;
287

    
288
    for (d = first_drv; d; d = d->next) {
289
        if (d->bdrv_probe_device) {
290
            score = d->bdrv_probe_device(filename);
291
            if (score > score_max) {
292
                score_max = score;
293
                drv = d;
294
            }
295
        }
296
    }
297

    
298
    return drv;
299
}
300

    
301
static BlockDriver *find_image_format(const char *filename)
302
{
303
    int ret, score, score_max;
304
    BlockDriver *drv1, *drv;
305
    uint8_t buf[2048];
306
    BlockDriverState *bs;
307

    
308
    drv = find_protocol(filename);
309
    /* no need to test disk image formats for vvfat */
310
    if (drv && strcmp(drv->format_name, "vvfat") == 0)
311
        return drv;
312

    
313
    ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
314
    if (ret < 0)
315
        return NULL;
316
    ret = bdrv_pread(bs, 0, buf, sizeof(buf));
317
    bdrv_delete(bs);
318
    if (ret < 0) {
319
        return NULL;
320
    }
321

    
322
    score_max = 0;
323
    for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
324
        if (drv1->bdrv_probe) {
325
            score = drv1->bdrv_probe(buf, ret, filename);
326
            if (score > score_max) {
327
                score_max = score;
328
                drv = drv1;
329
            }
330
        }
331
    }
332
    return drv;
333
}
334

    
335
int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
336
{
337
    BlockDriverState *bs;
338
    int ret;
339

    
340
    bs = bdrv_new("");
341
    ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL);
342
    if (ret < 0) {
343
        bdrv_delete(bs);
344
        return ret;
345
    }
346
    bs->growable = 1;
347
    *pbs = bs;
348
    return 0;
349
}
350

    
351
int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
352
{
353
    return bdrv_open2(bs, filename, flags, NULL);
354
}
355

    
356
int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
357
               BlockDriver *drv)
358
{
359
    int ret, open_flags, try_rw;
360
    char tmp_filename[PATH_MAX];
361
    char backing_filename[PATH_MAX];
362

    
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
        BlockDriver *bdrv_qcow2;
374
        QEMUOptionParameter *options;
375

    
376
        /* if snapshot, we create a temporary backing file and open it
377
           instead of opening 'filename' directly */
378

    
379
        /* if there is a backing file, use it */
380
        bs1 = bdrv_new("");
381
        ret = bdrv_open2(bs1, filename, 0, drv);
382
        if (ret < 0) {
383
            bdrv_delete(bs1);
384
            return ret;
385
        }
386
        total_size = bdrv_getlength(bs1) >> BDRV_SECTOR_BITS;
387

    
388
        if (bs1->drv && bs1->drv->protocol_name)
389
            is_protocol = 1;
390

    
391
        bdrv_delete(bs1);
392

    
393
        get_tmp_filename(tmp_filename, sizeof(tmp_filename));
394

    
395
        /* Real path is meaningless for protocols */
396
        if (is_protocol)
397
            snprintf(backing_filename, sizeof(backing_filename),
398
                     "%s", filename);
399
        else if (!realpath(filename, backing_filename))
400
            return -errno;
401

    
402
        bdrv_qcow2 = bdrv_find_format("qcow2");
403
        options = parse_option_parameters("", bdrv_qcow2->create_options, NULL);
404

    
405
        set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size * 512);
406
        set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename);
407
        if (drv) {
408
            set_option_parameter(options, BLOCK_OPT_BACKING_FMT,
409
                drv->format_name);
410
        }
411

    
412
        ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
413
        if (ret < 0) {
414
            return ret;
415
        }
416

    
417
        filename = tmp_filename;
418
        drv = bdrv_qcow2;
419
        bs->is_temporary = 1;
420
    }
421

    
422
    pstrcpy(bs->filename, sizeof(bs->filename), filename);
423
    if (flags & BDRV_O_FILE) {
424
        drv = find_protocol(filename);
425
    } else if (!drv) {
426
        drv = find_hdev_driver(filename);
427
        if (!drv) {
428
            drv = find_image_format(filename);
429
        }
430
    }
431
    if (!drv) {
432
        ret = -ENOENT;
433
        goto unlink_and_fail;
434
    }
435
    bs->drv = drv;
436
    bs->opaque = qemu_mallocz(drv->instance_size);
437

    
438
    /*
439
     * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a
440
     * write cache to the guest.  We do need the fdatasync to flush
441
     * out transactions for block allocations, and we maybe have a
442
     * volatile write cache in our backing device to deal with.
443
     */
444
    if (flags & (BDRV_O_CACHE_WB|BDRV_O_NOCACHE))
445
        bs->enable_write_cache = 1;
446

    
447
    /* Note: for compatibility, we open disk image files as RDWR, and
448
       RDONLY as fallback */
449
    try_rw = !bs->read_only || bs->is_temporary;
450
    if (!(flags & BDRV_O_FILE))
451
        open_flags = (try_rw ? BDRV_O_RDWR : 0) |
452
            (flags & (BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO));
453
    else
454
        open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
455
    if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv))
456
        ret = -ENOTSUP;
457
    else
458
        ret = drv->bdrv_open(bs, filename, open_flags);
459
    if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) {
460
        ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR);
461
        bs->read_only = 1;
462
    }
463
    if (ret < 0) {
464
        qemu_free(bs->opaque);
465
        bs->opaque = NULL;
466
        bs->drv = NULL;
467
    unlink_and_fail:
468
        if (bs->is_temporary)
469
            unlink(filename);
470
        return ret;
471
    }
472
    if (drv->bdrv_getlength) {
473
        bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
474
    }
475
#ifndef _WIN32
476
    if (bs->is_temporary) {
477
        unlink(filename);
478
    }
479
#endif
480
    if (bs->backing_file[0] != '\0') {
481
        /* if there is a backing file, use it */
482
        BlockDriver *back_drv = NULL;
483
        bs->backing_hd = bdrv_new("");
484
        /* pass on read_only property to the backing_hd */
485
        bs->backing_hd->read_only = bs->read_only;
486
        path_combine(backing_filename, sizeof(backing_filename),
487
                     filename, bs->backing_file);
488
        if (bs->backing_format[0] != '\0')
489
            back_drv = bdrv_find_format(bs->backing_format);
490
        ret = bdrv_open2(bs->backing_hd, backing_filename, open_flags,
491
                         back_drv);
492
        if (ret < 0) {
493
            bdrv_close(bs);
494
            return ret;
495
        }
496
    }
497

    
498
    if (!bdrv_key_required(bs)) {
499
        /* call the change callback */
500
        bs->media_changed = 1;
501
        if (bs->change_cb)
502
            bs->change_cb(bs->change_opaque);
503
    }
504
    return 0;
505
}
506

    
507
void bdrv_close(BlockDriverState *bs)
508
{
509
    if (bs->drv) {
510
        if (bs->backing_hd)
511
            bdrv_delete(bs->backing_hd);
512
        bs->drv->bdrv_close(bs);
513
        qemu_free(bs->opaque);
514
#ifdef _WIN32
515
        if (bs->is_temporary) {
516
            unlink(bs->filename);
517
        }
518
#endif
519
        bs->opaque = NULL;
520
        bs->drv = NULL;
521

    
522
        /* call the change callback */
523
        bs->media_changed = 1;
524
        if (bs->change_cb)
525
            bs->change_cb(bs->change_opaque);
526
    }
527
}
528

    
529
void bdrv_delete(BlockDriverState *bs)
530
{
531
    BlockDriverState **pbs;
532

    
533
    pbs = &bdrv_first;
534
    while (*pbs != bs && *pbs != NULL)
535
        pbs = &(*pbs)->next;
536
    if (*pbs == bs)
537
        *pbs = bs->next;
538

    
539
    bdrv_close(bs);
540
    qemu_free(bs);
541
}
542

    
543
/*
544
 * Run consistency checks on an image
545
 *
546
 * Returns the number of errors or -errno when an internal error occurs
547
 */
548
int bdrv_check(BlockDriverState *bs)
549
{
550
    if (bs->drv->bdrv_check == NULL) {
551
        return -ENOTSUP;
552
    }
553

    
554
    return bs->drv->bdrv_check(bs);
555
}
556

    
557
/* commit COW file into the raw image */
558
int bdrv_commit(BlockDriverState *bs)
559
{
560
    BlockDriver *drv = bs->drv;
561
    int64_t i, total_sectors;
562
    int n, j;
563
    unsigned char sector[512];
564

    
565
    if (!drv)
566
        return -ENOMEDIUM;
567

    
568
    if (bs->read_only) {
569
        return -EACCES;
570
    }
571

    
572
    if (!bs->backing_hd) {
573
        return -ENOTSUP;
574
    }
575

    
576
    total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
577
    for (i = 0; i < total_sectors;) {
578
        if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
579
            for(j = 0; j < n; j++) {
580
                if (bdrv_read(bs, i, sector, 1) != 0) {
581
                    return -EIO;
582
                }
583

    
584
                if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
585
                    return -EIO;
586
                }
587
                i++;
588
            }
589
        } else {
590
            i += n;
591
        }
592
    }
593

    
594
    if (drv->bdrv_make_empty)
595
        return drv->bdrv_make_empty(bs);
596

    
597
    return 0;
598
}
599

    
600
static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
601
                                   size_t size)
602
{
603
    int64_t len;
604

    
605
    if (!bdrv_is_inserted(bs))
606
        return -ENOMEDIUM;
607

    
608
    if (bs->growable)
609
        return 0;
610

    
611
    len = bdrv_getlength(bs);
612

    
613
    if (offset < 0)
614
        return -EIO;
615

    
616
    if ((offset > len) || (len - offset < size))
617
        return -EIO;
618

    
619
    return 0;
620
}
621

    
622
static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
623
                              int nb_sectors)
624
{
625
    return bdrv_check_byte_request(bs, sector_num * 512, nb_sectors * 512);
626
}
627

    
628
/* return < 0 if error. See bdrv_write() for the return codes */
629
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
630
              uint8_t *buf, int nb_sectors)
631
{
632
    BlockDriver *drv = bs->drv;
633

    
634
    if (!drv)
635
        return -ENOMEDIUM;
636
    if (bdrv_check_request(bs, sector_num, nb_sectors))
637
        return -EIO;
638

    
639
    return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
640
}
641

    
642
static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num,
643
                             int nb_sectors, int dirty)
644
{
645
    int64_t start, end;
646
    unsigned long val, idx, bit;
647

    
648
    start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
649
    end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
650

    
651
    for (; start <= end; start++) {
652
        idx = start / (sizeof(unsigned long) * 8);
653
        bit = start % (sizeof(unsigned long) * 8);
654
        val = bs->dirty_bitmap[idx];
655
        if (dirty) {
656
            val |= 1 << bit;
657
        } else {
658
            val &= ~(1 << bit);
659
        }
660
        bs->dirty_bitmap[idx] = val;
661
    }
662
}
663

    
664
/* Return < 0 if error. Important errors are:
665
  -EIO         generic I/O error (may happen for all errors)
666
  -ENOMEDIUM   No media inserted.
667
  -EINVAL      Invalid sector number or nb_sectors
668
  -EACCES      Trying to write a read-only device
669
*/
670
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
671
               const uint8_t *buf, int nb_sectors)
672
{
673
    BlockDriver *drv = bs->drv;
674
    if (!bs->drv)
675
        return -ENOMEDIUM;
676
    if (bs->read_only)
677
        return -EACCES;
678
    if (bdrv_check_request(bs, sector_num, nb_sectors))
679
        return -EIO;
680

    
681
    if (bs->dirty_bitmap) {
682
        set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
683
    }
684

    
685
    return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
686
}
687

    
688
int bdrv_pread(BlockDriverState *bs, int64_t offset,
689
               void *buf, int count1)
690
{
691
    uint8_t tmp_buf[BDRV_SECTOR_SIZE];
692
    int len, nb_sectors, count;
693
    int64_t sector_num;
694

    
695
    count = count1;
696
    /* first read to align to sector start */
697
    len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
698
    if (len > count)
699
        len = count;
700
    sector_num = offset >> BDRV_SECTOR_BITS;
701
    if (len > 0) {
702
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
703
            return -EIO;
704
        memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len);
705
        count -= len;
706
        if (count == 0)
707
            return count1;
708
        sector_num++;
709
        buf += len;
710
    }
711

    
712
    /* read the sectors "in place" */
713
    nb_sectors = count >> BDRV_SECTOR_BITS;
714
    if (nb_sectors > 0) {
715
        if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0)
716
            return -EIO;
717
        sector_num += nb_sectors;
718
        len = nb_sectors << BDRV_SECTOR_BITS;
719
        buf += len;
720
        count -= len;
721
    }
722

    
723
    /* add data from the last sector */
724
    if (count > 0) {
725
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
726
            return -EIO;
727
        memcpy(buf, tmp_buf, count);
728
    }
729
    return count1;
730
}
731

    
732
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
733
                const void *buf, int count1)
734
{
735
    uint8_t tmp_buf[BDRV_SECTOR_SIZE];
736
    int len, nb_sectors, count;
737
    int64_t sector_num;
738

    
739
    count = count1;
740
    /* first write to align to sector start */
741
    len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
742
    if (len > count)
743
        len = count;
744
    sector_num = offset >> BDRV_SECTOR_BITS;
745
    if (len > 0) {
746
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
747
            return -EIO;
748
        memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len);
749
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
750
            return -EIO;
751
        count -= len;
752
        if (count == 0)
753
            return count1;
754
        sector_num++;
755
        buf += len;
756
    }
757

    
758
    /* write the sectors "in place" */
759
    nb_sectors = count >> BDRV_SECTOR_BITS;
760
    if (nb_sectors > 0) {
761
        if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
762
            return -EIO;
763
        sector_num += nb_sectors;
764
        len = nb_sectors << BDRV_SECTOR_BITS;
765
        buf += len;
766
        count -= len;
767
    }
768

    
769
    /* add data from the last sector */
770
    if (count > 0) {
771
        if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
772
            return -EIO;
773
        memcpy(tmp_buf, buf, count);
774
        if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
775
            return -EIO;
776
    }
777
    return count1;
778
}
779

    
780
/**
781
 * Truncate file to 'offset' bytes (needed only for file protocols)
782
 */
783
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
784
{
785
    BlockDriver *drv = bs->drv;
786
    if (!drv)
787
        return -ENOMEDIUM;
788
    if (!drv->bdrv_truncate)
789
        return -ENOTSUP;
790
    if (bs->read_only)
791
        return -EACCES;
792
    return drv->bdrv_truncate(bs, offset);
793
}
794

    
795
/**
796
 * Length of a file in bytes. Return < 0 if error or unknown.
797
 */
798
int64_t bdrv_getlength(BlockDriverState *bs)
799
{
800
    BlockDriver *drv = bs->drv;
801
    if (!drv)
802
        return -ENOMEDIUM;
803
    if (!drv->bdrv_getlength) {
804
        /* legacy mode */
805
        return bs->total_sectors * BDRV_SECTOR_SIZE;
806
    }
807
    return drv->bdrv_getlength(bs);
808
}
809

    
810
/* return 0 as number of sectors if no device present or error */
811
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
812
{
813
    int64_t length;
814
    length = bdrv_getlength(bs);
815
    if (length < 0)
816
        length = 0;
817
    else
818
        length = length >> BDRV_SECTOR_BITS;
819
    *nb_sectors_ptr = length;
820
}
821

    
822
struct partition {
823
        uint8_t boot_ind;           /* 0x80 - active */
824
        uint8_t head;               /* starting head */
825
        uint8_t sector;             /* starting sector */
826
        uint8_t cyl;                /* starting cylinder */
827
        uint8_t sys_ind;            /* What partition type */
828
        uint8_t end_head;           /* end head */
829
        uint8_t end_sector;         /* end sector */
830
        uint8_t end_cyl;            /* end cylinder */
831
        uint32_t start_sect;        /* starting sector counting from 0 */
832
        uint32_t nr_sects;          /* nr of sectors in partition */
833
} __attribute__((packed));
834

    
835
/* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
836
static int guess_disk_lchs(BlockDriverState *bs,
837
                           int *pcylinders, int *pheads, int *psectors)
838
{
839
    uint8_t buf[512];
840
    int ret, i, heads, sectors, cylinders;
841
    struct partition *p;
842
    uint32_t nr_sects;
843
    uint64_t nb_sectors;
844

    
845
    bdrv_get_geometry(bs, &nb_sectors);
846

    
847
    ret = bdrv_read(bs, 0, buf, 1);
848
    if (ret < 0)
849
        return -1;
850
    /* test msdos magic */
851
    if (buf[510] != 0x55 || buf[511] != 0xaa)
852
        return -1;
853
    for(i = 0; i < 4; i++) {
854
        p = ((struct partition *)(buf + 0x1be)) + i;
855
        nr_sects = le32_to_cpu(p->nr_sects);
856
        if (nr_sects && p->end_head) {
857
            /* We make the assumption that the partition terminates on
858
               a cylinder boundary */
859
            heads = p->end_head + 1;
860
            sectors = p->end_sector & 63;
861
            if (sectors == 0)
862
                continue;
863
            cylinders = nb_sectors / (heads * sectors);
864
            if (cylinders < 1 || cylinders > 16383)
865
                continue;
866
            *pheads = heads;
867
            *psectors = sectors;
868
            *pcylinders = cylinders;
869
#if 0
870
            printf("guessed geometry: LCHS=%d %d %d\n",
871
                   cylinders, heads, sectors);
872
#endif
873
            return 0;
874
        }
875
    }
876
    return -1;
877
}
878

    
879
void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
880
{
881
    int translation, lba_detected = 0;
882
    int cylinders, heads, secs;
883
    uint64_t nb_sectors;
884

    
885
    /* if a geometry hint is available, use it */
886
    bdrv_get_geometry(bs, &nb_sectors);
887
    bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
888
    translation = bdrv_get_translation_hint(bs);
889
    if (cylinders != 0) {
890
        *pcyls = cylinders;
891
        *pheads = heads;
892
        *psecs = secs;
893
    } else {
894
        if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
895
            if (heads > 16) {
896
                /* if heads > 16, it means that a BIOS LBA
897
                   translation was active, so the default
898
                   hardware geometry is OK */
899
                lba_detected = 1;
900
                goto default_geometry;
901
            } else {
902
                *pcyls = cylinders;
903
                *pheads = heads;
904
                *psecs = secs;
905
                /* disable any translation to be in sync with
906
                   the logical geometry */
907
                if (translation == BIOS_ATA_TRANSLATION_AUTO) {
908
                    bdrv_set_translation_hint(bs,
909
                                              BIOS_ATA_TRANSLATION_NONE);
910
                }
911
            }
912
        } else {
913
        default_geometry:
914
            /* if no geometry, use a standard physical disk geometry */
915
            cylinders = nb_sectors / (16 * 63);
916

    
917
            if (cylinders > 16383)
918
                cylinders = 16383;
919
            else if (cylinders < 2)
920
                cylinders = 2;
921
            *pcyls = cylinders;
922
            *pheads = 16;
923
            *psecs = 63;
924
            if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
925
                if ((*pcyls * *pheads) <= 131072) {
926
                    bdrv_set_translation_hint(bs,
927
                                              BIOS_ATA_TRANSLATION_LARGE);
928
                } else {
929
                    bdrv_set_translation_hint(bs,
930
                                              BIOS_ATA_TRANSLATION_LBA);
931
                }
932
            }
933
        }
934
        bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
935
    }
936
}
937

    
938
void bdrv_set_geometry_hint(BlockDriverState *bs,
939
                            int cyls, int heads, int secs)
940
{
941
    bs->cyls = cyls;
942
    bs->heads = heads;
943
    bs->secs = secs;
944
}
945

    
946
void bdrv_set_type_hint(BlockDriverState *bs, int type)
947
{
948
    bs->type = type;
949
    bs->removable = ((type == BDRV_TYPE_CDROM ||
950
                      type == BDRV_TYPE_FLOPPY));
951
}
952

    
953
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
954
{
955
    bs->translation = translation;
956
}
957

    
958
void bdrv_get_geometry_hint(BlockDriverState *bs,
959
                            int *pcyls, int *pheads, int *psecs)
960
{
961
    *pcyls = bs->cyls;
962
    *pheads = bs->heads;
963
    *psecs = bs->secs;
964
}
965

    
966
int bdrv_get_type_hint(BlockDriverState *bs)
967
{
968
    return bs->type;
969
}
970

    
971
int bdrv_get_translation_hint(BlockDriverState *bs)
972
{
973
    return bs->translation;
974
}
975

    
976
int bdrv_is_removable(BlockDriverState *bs)
977
{
978
    return bs->removable;
979
}
980

    
981
int bdrv_is_read_only(BlockDriverState *bs)
982
{
983
    return bs->read_only;
984
}
985

    
986
int bdrv_set_read_only(BlockDriverState *bs, int read_only)
987
{
988
    int ret = bs->read_only;
989
    bs->read_only = read_only;
990
    return ret;
991
}
992

    
993
int bdrv_is_sg(BlockDriverState *bs)
994
{
995
    return bs->sg;
996
}
997

    
998
int bdrv_enable_write_cache(BlockDriverState *bs)
999
{
1000
    return bs->enable_write_cache;
1001
}
1002

    
1003
/* XXX: no longer used */
1004
void bdrv_set_change_cb(BlockDriverState *bs,
1005
                        void (*change_cb)(void *opaque), void *opaque)
1006
{
1007
    bs->change_cb = change_cb;
1008
    bs->change_opaque = opaque;
1009
}
1010

    
1011
int bdrv_is_encrypted(BlockDriverState *bs)
1012
{
1013
    if (bs->backing_hd && bs->backing_hd->encrypted)
1014
        return 1;
1015
    return bs->encrypted;
1016
}
1017

    
1018
int bdrv_key_required(BlockDriverState *bs)
1019
{
1020
    BlockDriverState *backing_hd = bs->backing_hd;
1021

    
1022
    if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
1023
        return 1;
1024
    return (bs->encrypted && !bs->valid_key);
1025
}
1026

    
1027
int bdrv_set_key(BlockDriverState *bs, const char *key)
1028
{
1029
    int ret;
1030
    if (bs->backing_hd && bs->backing_hd->encrypted) {
1031
        ret = bdrv_set_key(bs->backing_hd, key);
1032
        if (ret < 0)
1033
            return ret;
1034
        if (!bs->encrypted)
1035
            return 0;
1036
    }
1037
    if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
1038
        return -1;
1039
    ret = bs->drv->bdrv_set_key(bs, key);
1040
    if (ret < 0) {
1041
        bs->valid_key = 0;
1042
    } else if (!bs->valid_key) {
1043
        bs->valid_key = 1;
1044
        /* call the change callback now, we skipped it on open */
1045
        bs->media_changed = 1;
1046
        if (bs->change_cb)
1047
            bs->change_cb(bs->change_opaque);
1048
    }
1049
    return ret;
1050
}
1051

    
1052
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
1053
{
1054
    if (!bs->drv) {
1055
        buf[0] = '\0';
1056
    } else {
1057
        pstrcpy(buf, buf_size, bs->drv->format_name);
1058
    }
1059
}
1060

    
1061
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
1062
                         void *opaque)
1063
{
1064
    BlockDriver *drv;
1065

    
1066
    for (drv = first_drv; drv != NULL; drv = drv->next) {
1067
        it(opaque, drv->format_name);
1068
    }
1069
}
1070

    
1071
BlockDriverState *bdrv_find(const char *name)
1072
{
1073
    BlockDriverState *bs;
1074

    
1075
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1076
        if (!strcmp(name, bs->device_name))
1077
            return bs;
1078
    }
1079
    return NULL;
1080
}
1081

    
1082
void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
1083
{
1084
    BlockDriverState *bs;
1085

    
1086
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1087
        it(opaque, bs);
1088
    }
1089
}
1090

    
1091
const char *bdrv_get_device_name(BlockDriverState *bs)
1092
{
1093
    return bs->device_name;
1094
}
1095

    
1096
void bdrv_flush(BlockDriverState *bs)
1097
{
1098
    if (!bs->drv)
1099
        return;
1100
    if (bs->drv->bdrv_flush)
1101
        bs->drv->bdrv_flush(bs);
1102
    if (bs->backing_hd)
1103
        bdrv_flush(bs->backing_hd);
1104
}
1105

    
1106
void bdrv_flush_all(void)
1107
{
1108
    BlockDriverState *bs;
1109

    
1110
    for (bs = bdrv_first; bs != NULL; bs = bs->next)
1111
        if (bs->drv && !bdrv_is_read_only(bs) && 
1112
            (!bdrv_is_removable(bs) || bdrv_is_inserted(bs)))
1113
            bdrv_flush(bs);
1114
}
1115

    
1116
/*
1117
 * Returns true iff the specified sector is present in the disk image. Drivers
1118
 * not implementing the functionality are assumed to not support backing files,
1119
 * hence all their sectors are reported as allocated.
1120
 *
1121
 * 'pnum' is set to the number of sectors (including and immediately following
1122
 * the specified sector) that are known to be in the same
1123
 * allocated/unallocated state.
1124
 *
1125
 * 'nb_sectors' is the max value 'pnum' should be set to.
1126
 */
1127
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
1128
        int *pnum)
1129
{
1130
    int64_t n;
1131
    if (!bs->drv->bdrv_is_allocated) {
1132
        if (sector_num >= bs->total_sectors) {
1133
            *pnum = 0;
1134
            return 0;
1135
        }
1136
        n = bs->total_sectors - sector_num;
1137
        *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
1138
        return 1;
1139
    }
1140
    return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
1141
}
1142

    
1143
static void bdrv_print_dict(QObject *obj, void *opaque)
1144
{
1145
    QDict *bs_dict;
1146
    Monitor *mon = opaque;
1147

    
1148
    bs_dict = qobject_to_qdict(obj);
1149

    
1150
    monitor_printf(mon, "%s: type=%s removable=%d",
1151
                        qdict_get_str(bs_dict, "device"),
1152
                        qdict_get_str(bs_dict, "type"),
1153
                        qdict_get_bool(bs_dict, "removable"));
1154

    
1155
    if (qdict_get_bool(bs_dict, "removable")) {
1156
        monitor_printf(mon, " locked=%d", qdict_get_bool(bs_dict, "locked"));
1157
    }
1158

    
1159
    if (qdict_haskey(bs_dict, "inserted")) {
1160
        QDict *qdict = qobject_to_qdict(qdict_get(bs_dict, "inserted"));
1161

    
1162
        monitor_printf(mon, " file=");
1163
        monitor_print_filename(mon, qdict_get_str(qdict, "file"));
1164
        if (qdict_haskey(qdict, "backing_file")) {
1165
            monitor_printf(mon, " backing_file=");
1166
            monitor_print_filename(mon, qdict_get_str(qdict, "backing_file"));
1167
        }
1168
        monitor_printf(mon, " ro=%d drv=%s encrypted=%d",
1169
                            qdict_get_bool(qdict, "ro"),
1170
                            qdict_get_str(qdict, "drv"),
1171
                            qdict_get_bool(qdict, "encrypted"));
1172
    } else {
1173
        monitor_printf(mon, " [not inserted]");
1174
    }
1175

    
1176
    monitor_printf(mon, "\n");
1177
}
1178

    
1179
void bdrv_info_print(Monitor *mon, const QObject *data)
1180
{
1181
    qlist_iter(qobject_to_qlist(data), bdrv_print_dict, mon);
1182
}
1183

    
1184
/**
1185
 * bdrv_info(): Block devices information
1186
 *
1187
 * Each block device information is stored in a QDict and the
1188
 * returned QObject is a QList of all devices.
1189
 *
1190
 * The QDict contains the following:
1191
 *
1192
 * - "device": device name
1193
 * - "type": device type
1194
 * - "removable": true if the device is removable, false otherwise
1195
 * - "locked": true if the device is locked, false otherwise
1196
 * - "inserted": only present if the device is inserted, it is a QDict
1197
 *    containing the following:
1198
 *          - "file": device file name
1199
 *          - "ro": true if read-only, false otherwise
1200
 *          - "drv": driver format name
1201
 *          - "backing_file": backing file name if one is used
1202
 *          - "encrypted": true if encrypted, false otherwise
1203
 *
1204
 * Example:
1205
 *
1206
 * [ { "device": "ide0-hd0", "type": "hd", "removable": false, "locked": false,
1207
 *     "inserted": { "file": "/tmp/foobar", "ro": false, "drv": "qcow2" } },
1208
 *   { "device": "floppy0", "type": "floppy", "removable": true,
1209
 *     "locked": false } ]
1210
 */
1211
void bdrv_info(Monitor *mon, QObject **ret_data)
1212
{
1213
    QList *bs_list;
1214
    BlockDriverState *bs;
1215

    
1216
    bs_list = qlist_new();
1217

    
1218
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1219
        QObject *bs_obj;
1220
        const char *type = "unknown";
1221

    
1222
        switch(bs->type) {
1223
        case BDRV_TYPE_HD:
1224
            type = "hd";
1225
            break;
1226
        case BDRV_TYPE_CDROM:
1227
            type = "cdrom";
1228
            break;
1229
        case BDRV_TYPE_FLOPPY:
1230
            type = "floppy";
1231
            break;
1232
        }
1233

    
1234
        bs_obj = qobject_from_jsonf("{ 'device': %s, 'type': %s, "
1235
                                    "'removable': %i, 'locked': %i }",
1236
                                    bs->device_name, type, bs->removable,
1237
                                    bs->locked);
1238
        assert(bs_obj != NULL);
1239

    
1240
        if (bs->drv) {
1241
            QObject *obj;
1242
            QDict *bs_dict = qobject_to_qdict(bs_obj);
1243

    
1244
            obj = qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, "
1245
                                     "'encrypted': %i }",
1246
                                     bs->filename, bs->read_only,
1247
                                     bs->drv->format_name,
1248
                                     bdrv_is_encrypted(bs));
1249
            assert(obj != NULL);
1250
            if (bs->backing_file[0] != '\0') {
1251
                QDict *qdict = qobject_to_qdict(obj);
1252
                qdict_put(qdict, "backing_file",
1253
                          qstring_from_str(bs->backing_file));
1254
            }
1255

    
1256
            qdict_put_obj(bs_dict, "inserted", obj);
1257
        }
1258
        qlist_append_obj(bs_list, bs_obj);
1259
    }
1260

    
1261
    *ret_data = QOBJECT(bs_list);
1262
}
1263

    
1264
static void bdrv_stats_iter(QObject *data, void *opaque)
1265
{
1266
    QDict *qdict;
1267
    Monitor *mon = opaque;
1268

    
1269
    qdict = qobject_to_qdict(data);
1270
    monitor_printf(mon, "%s:", qdict_get_str(qdict, "device"));
1271

    
1272
    qdict = qobject_to_qdict(qdict_get(qdict, "stats"));
1273
    monitor_printf(mon, " rd_bytes=%" PRId64
1274
                        " wr_bytes=%" PRId64
1275
                        " rd_operations=%" PRId64
1276
                        " wr_operations=%" PRId64
1277
                        "\n",
1278
                        qdict_get_int(qdict, "rd_bytes"),
1279
                        qdict_get_int(qdict, "wr_bytes"),
1280
                        qdict_get_int(qdict, "rd_operations"),
1281
                        qdict_get_int(qdict, "wr_operations"));
1282
}
1283

    
1284
void bdrv_stats_print(Monitor *mon, const QObject *data)
1285
{
1286
    qlist_iter(qobject_to_qlist(data), bdrv_stats_iter, mon);
1287
}
1288

    
1289
/**
1290
 * bdrv_info_stats(): show block device statistics
1291
 *
1292
 * Each device statistic information is stored in a QDict and
1293
 * the returned QObject is a QList of all devices.
1294
 *
1295
 * The QDict contains the following:
1296
 *
1297
 * - "device": device name
1298
 * - "stats": A QDict with the statistics information, it contains:
1299
 *     - "rd_bytes": bytes read
1300
 *     - "wr_bytes": bytes written
1301
 *     - "rd_operations": read operations
1302
 *     - "wr_operations": write operations
1303
 * 
1304
 * Example:
1305
 *
1306
 * [ { "device": "ide0-hd0",
1307
 *               "stats": { "rd_bytes": 512,
1308
 *                          "wr_bytes": 0,
1309
 *                          "rd_operations": 1,
1310
 *                          "wr_operations": 0 } },
1311
 *   { "device": "ide1-cd0",
1312
 *               "stats": { "rd_bytes": 0,
1313
 *                          "wr_bytes": 0,
1314
 *                          "rd_operations": 0,
1315
 *                          "wr_operations": 0 } } ]
1316
 */
1317
void bdrv_info_stats(Monitor *mon, QObject **ret_data)
1318
{
1319
    QObject *obj;
1320
    QList *devices;
1321
    BlockDriverState *bs;
1322

    
1323
    devices = qlist_new();
1324

    
1325
    for (bs = bdrv_first; bs != NULL; bs = bs->next) {
1326
        obj = qobject_from_jsonf("{ 'device': %s, 'stats': {"
1327
                                 "'rd_bytes': %" PRId64 ","
1328
                                 "'wr_bytes': %" PRId64 ","
1329
                                 "'rd_operations': %" PRId64 ","
1330
                                 "'wr_operations': %" PRId64
1331
                                 "} }",
1332
                                 bs->device_name,
1333
                                 bs->rd_bytes, bs->wr_bytes,
1334
                                 bs->rd_ops, bs->wr_ops);
1335
        assert(obj != NULL);
1336
        qlist_append_obj(devices, obj);
1337
    }
1338

    
1339
    *ret_data = QOBJECT(devices);
1340
}
1341

    
1342
const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
1343
{
1344
    if (bs->backing_hd && bs->backing_hd->encrypted)
1345
        return bs->backing_file;
1346
    else if (bs->encrypted)
1347
        return bs->filename;
1348
    else
1349
        return NULL;
1350
}
1351

    
1352
void bdrv_get_backing_filename(BlockDriverState *bs,
1353
                               char *filename, int filename_size)
1354
{
1355
    if (!bs->backing_hd) {
1356
        pstrcpy(filename, filename_size, "");
1357
    } else {
1358
        pstrcpy(filename, filename_size, bs->backing_file);
1359
    }
1360
}
1361

    
1362
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
1363
                          const uint8_t *buf, int nb_sectors)
1364
{
1365
    BlockDriver *drv = bs->drv;
1366
    if (!drv)
1367
        return -ENOMEDIUM;
1368
    if (!drv->bdrv_write_compressed)
1369
        return -ENOTSUP;
1370
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1371
        return -EIO;
1372

    
1373
    if (bs->dirty_bitmap) {
1374
        set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
1375
    }
1376

    
1377
    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
1378
}
1379

    
1380
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1381
{
1382
    BlockDriver *drv = bs->drv;
1383
    if (!drv)
1384
        return -ENOMEDIUM;
1385
    if (!drv->bdrv_get_info)
1386
        return -ENOTSUP;
1387
    memset(bdi, 0, sizeof(*bdi));
1388
    return drv->bdrv_get_info(bs, bdi);
1389
}
1390

    
1391
int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
1392
                      int64_t pos, int size)
1393
{
1394
    BlockDriver *drv = bs->drv;
1395
    if (!drv)
1396
        return -ENOMEDIUM;
1397
    if (!drv->bdrv_save_vmstate)
1398
        return -ENOTSUP;
1399
    return drv->bdrv_save_vmstate(bs, buf, pos, size);
1400
}
1401

    
1402
int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
1403
                      int64_t pos, int size)
1404
{
1405
    BlockDriver *drv = bs->drv;
1406
    if (!drv)
1407
        return -ENOMEDIUM;
1408
    if (!drv->bdrv_load_vmstate)
1409
        return -ENOTSUP;
1410
    return drv->bdrv_load_vmstate(bs, buf, pos, size);
1411
}
1412

    
1413
/**************************************************************/
1414
/* handling of snapshots */
1415

    
1416
int bdrv_snapshot_create(BlockDriverState *bs,
1417
                         QEMUSnapshotInfo *sn_info)
1418
{
1419
    BlockDriver *drv = bs->drv;
1420
    if (!drv)
1421
        return -ENOMEDIUM;
1422
    if (!drv->bdrv_snapshot_create)
1423
        return -ENOTSUP;
1424
    return drv->bdrv_snapshot_create(bs, sn_info);
1425
}
1426

    
1427
int bdrv_snapshot_goto(BlockDriverState *bs,
1428
                       const char *snapshot_id)
1429
{
1430
    BlockDriver *drv = bs->drv;
1431
    if (!drv)
1432
        return -ENOMEDIUM;
1433
    if (!drv->bdrv_snapshot_goto)
1434
        return -ENOTSUP;
1435
    return drv->bdrv_snapshot_goto(bs, snapshot_id);
1436
}
1437

    
1438
int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
1439
{
1440
    BlockDriver *drv = bs->drv;
1441
    if (!drv)
1442
        return -ENOMEDIUM;
1443
    if (!drv->bdrv_snapshot_delete)
1444
        return -ENOTSUP;
1445
    return drv->bdrv_snapshot_delete(bs, snapshot_id);
1446
}
1447

    
1448
int bdrv_snapshot_list(BlockDriverState *bs,
1449
                       QEMUSnapshotInfo **psn_info)
1450
{
1451
    BlockDriver *drv = bs->drv;
1452
    if (!drv)
1453
        return -ENOMEDIUM;
1454
    if (!drv->bdrv_snapshot_list)
1455
        return -ENOTSUP;
1456
    return drv->bdrv_snapshot_list(bs, psn_info);
1457
}
1458

    
1459
#define NB_SUFFIXES 4
1460

    
1461
char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1462
{
1463
    static const char suffixes[NB_SUFFIXES] = "KMGT";
1464
    int64_t base;
1465
    int i;
1466

    
1467
    if (size <= 999) {
1468
        snprintf(buf, buf_size, "%" PRId64, size);
1469
    } else {
1470
        base = 1024;
1471
        for(i = 0; i < NB_SUFFIXES; i++) {
1472
            if (size < (10 * base)) {
1473
                snprintf(buf, buf_size, "%0.1f%c",
1474
                         (double)size / base,
1475
                         suffixes[i]);
1476
                break;
1477
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1478
                snprintf(buf, buf_size, "%" PRId64 "%c",
1479
                         ((size + (base >> 1)) / base),
1480
                         suffixes[i]);
1481
                break;
1482
            }
1483
            base = base * 1024;
1484
        }
1485
    }
1486
    return buf;
1487
}
1488

    
1489
char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1490
{
1491
    char buf1[128], date_buf[128], clock_buf[128];
1492
#ifdef _WIN32
1493
    struct tm *ptm;
1494
#else
1495
    struct tm tm;
1496
#endif
1497
    time_t ti;
1498
    int64_t secs;
1499

    
1500
    if (!sn) {
1501
        snprintf(buf, buf_size,
1502
                 "%-10s%-20s%7s%20s%15s",
1503
                 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1504
    } else {
1505
        ti = sn->date_sec;
1506
#ifdef _WIN32
1507
        ptm = localtime(&ti);
1508
        strftime(date_buf, sizeof(date_buf),
1509
                 "%Y-%m-%d %H:%M:%S", ptm);
1510
#else
1511
        localtime_r(&ti, &tm);
1512
        strftime(date_buf, sizeof(date_buf),
1513
                 "%Y-%m-%d %H:%M:%S", &tm);
1514
#endif
1515
        secs = sn->vm_clock_nsec / 1000000000;
1516
        snprintf(clock_buf, sizeof(clock_buf),
1517
                 "%02d:%02d:%02d.%03d",
1518
                 (int)(secs / 3600),
1519
                 (int)((secs / 60) % 60),
1520
                 (int)(secs % 60),
1521
                 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1522
        snprintf(buf, buf_size,
1523
                 "%-10s%-20s%7s%20s%15s",
1524
                 sn->id_str, sn->name,
1525
                 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1526
                 date_buf,
1527
                 clock_buf);
1528
    }
1529
    return buf;
1530
}
1531

    
1532

    
1533
/**************************************************************/
1534
/* async I/Os */
1535

    
1536
BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
1537
                                 QEMUIOVector *qiov, int nb_sectors,
1538
                                 BlockDriverCompletionFunc *cb, void *opaque)
1539
{
1540
    BlockDriver *drv = bs->drv;
1541
    BlockDriverAIOCB *ret;
1542

    
1543
    if (!drv)
1544
        return NULL;
1545
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1546
        return NULL;
1547

    
1548
    ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
1549
                              cb, opaque);
1550

    
1551
    if (ret) {
1552
        /* Update stats even though technically transfer has not happened. */
1553
        bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
1554
        bs->rd_ops ++;
1555
    }
1556

    
1557
    return ret;
1558
}
1559

    
1560
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
1561
                                  QEMUIOVector *qiov, int nb_sectors,
1562
                                  BlockDriverCompletionFunc *cb, void *opaque)
1563
{
1564
    BlockDriver *drv = bs->drv;
1565
    BlockDriverAIOCB *ret;
1566

    
1567
    if (!drv)
1568
        return NULL;
1569
    if (bs->read_only)
1570
        return NULL;
1571
    if (bdrv_check_request(bs, sector_num, nb_sectors))
1572
        return NULL;
1573

    
1574
    if (bs->dirty_bitmap) {
1575
        set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
1576
    }
1577

    
1578
    ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors,
1579
                               cb, opaque);
1580

    
1581
    if (ret) {
1582
        /* Update stats even though technically transfer has not happened. */
1583
        bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
1584
        bs->wr_ops ++;
1585
    }
1586

    
1587
    return ret;
1588
}
1589

    
1590

    
1591
typedef struct MultiwriteCB {
1592
    int error;
1593
    int num_requests;
1594
    int num_callbacks;
1595
    struct {
1596
        BlockDriverCompletionFunc *cb;
1597
        void *opaque;
1598
        QEMUIOVector *free_qiov;
1599
        void *free_buf;
1600
    } callbacks[];
1601
} MultiwriteCB;
1602

    
1603
static void multiwrite_user_cb(MultiwriteCB *mcb)
1604
{
1605
    int i;
1606

    
1607
    for (i = 0; i < mcb->num_callbacks; i++) {
1608
        mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error);
1609
        qemu_free(mcb->callbacks[i].free_qiov);
1610
        qemu_free(mcb->callbacks[i].free_buf);
1611
    }
1612
}
1613

    
1614
static void multiwrite_cb(void *opaque, int ret)
1615
{
1616
    MultiwriteCB *mcb = opaque;
1617

    
1618
    if (ret < 0) {
1619
        mcb->error = ret;
1620
        multiwrite_user_cb(mcb);
1621
    }
1622

    
1623
    mcb->num_requests--;
1624
    if (mcb->num_requests == 0) {
1625
        if (mcb->error == 0) {
1626
            multiwrite_user_cb(mcb);
1627
        }
1628
        qemu_free(mcb);
1629
    }
1630
}
1631

    
1632
static int multiwrite_req_compare(const void *a, const void *b)
1633
{
1634
    return (((BlockRequest*) a)->sector - ((BlockRequest*) b)->sector);
1635
}
1636

    
1637
/*
1638
 * Takes a bunch of requests and tries to merge them. Returns the number of
1639
 * requests that remain after merging.
1640
 */
1641
static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
1642
    int num_reqs, MultiwriteCB *mcb)
1643
{
1644
    int i, outidx;
1645

    
1646
    // Sort requests by start sector
1647
    qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare);
1648

    
1649
    // Check if adjacent requests touch the same clusters. If so, combine them,
1650
    // filling up gaps with zero sectors.
1651
    outidx = 0;
1652
    for (i = 1; i < num_reqs; i++) {
1653
        int merge = 0;
1654
        int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors;
1655

    
1656
        // This handles the cases that are valid for all block drivers, namely
1657
        // exactly sequential writes and overlapping writes.
1658
        if (reqs[i].sector <= oldreq_last) {
1659
            merge = 1;
1660
        }
1661

    
1662
        // The block driver may decide that it makes sense to combine requests
1663
        // even if there is a gap of some sectors between them. In this case,
1664
        // the gap is filled with zeros (therefore only applicable for yet
1665
        // unused space in format like qcow2).
1666
        if (!merge && bs->drv->bdrv_merge_requests) {
1667
            merge = bs->drv->bdrv_merge_requests(bs, &reqs[outidx], &reqs[i]);
1668
        }
1669

    
1670
        if (merge) {
1671
            size_t size;
1672
            QEMUIOVector *qiov = qemu_mallocz(sizeof(*qiov));
1673
            qemu_iovec_init(qiov,
1674
                reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1);
1675

    
1676
            // Add the first request to the merged one. If the requests are
1677
            // overlapping, drop the last sectors of the first request.
1678
            size = (reqs[i].sector - reqs[outidx].sector) << 9;
1679
            qemu_iovec_concat(qiov, reqs[outidx].qiov, size);
1680

    
1681
            // We might need to add some zeros between the two requests
1682
            if (reqs[i].sector > oldreq_last) {
1683
                size_t zero_bytes = (reqs[i].sector - oldreq_last) << 9;
1684
                uint8_t *buf = qemu_blockalign(bs, zero_bytes);
1685
                memset(buf, 0, zero_bytes);
1686
                qemu_iovec_add(qiov, buf, zero_bytes);
1687
                mcb->callbacks[i].free_buf = buf;
1688
            }
1689

    
1690
            // Add the second request
1691
            qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size);
1692

    
1693
            reqs[outidx].nb_sectors += reqs[i].nb_sectors;
1694
            reqs[outidx].qiov = qiov;
1695

    
1696
            mcb->callbacks[i].free_qiov = reqs[outidx].qiov;
1697
        } else {
1698
            outidx++;
1699
            reqs[outidx].sector     = reqs[i].sector;
1700
            reqs[outidx].nb_sectors = reqs[i].nb_sectors;
1701
            reqs[outidx].qiov       = reqs[i].qiov;
1702
        }
1703
    }
1704

    
1705
    return outidx + 1;
1706
}
1707

    
1708
/*
1709
 * Submit multiple AIO write requests at once.
1710
 *
1711
 * On success, the function returns 0 and all requests in the reqs array have
1712
 * been submitted. In error case this function returns -1, and any of the
1713
 * requests may or may not be submitted yet. In particular, this means that the
1714
 * callback will be called for some of the requests, for others it won't. The
1715
 * caller must check the error field of the BlockRequest to wait for the right
1716
 * callbacks (if error != 0, no callback will be called).
1717
 *
1718
 * The implementation may modify the contents of the reqs array, e.g. to merge
1719
 * requests. However, the fields opaque and error are left unmodified as they
1720
 * are used to signal failure for a single request to the caller.
1721
 */
1722
int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs)
1723
{
1724
    BlockDriverAIOCB *acb;
1725
    MultiwriteCB *mcb;
1726
    int i;
1727

    
1728
    if (num_reqs == 0) {
1729
        return 0;
1730
    }
1731

    
1732
    // Create MultiwriteCB structure
1733
    mcb = qemu_mallocz(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks));
1734
    mcb->num_requests = 0;
1735
    mcb->num_callbacks = num_reqs;
1736

    
1737
    for (i = 0; i < num_reqs; i++) {
1738
        mcb->callbacks[i].cb = reqs[i].cb;
1739
        mcb->callbacks[i].opaque = reqs[i].opaque;
1740
    }
1741

    
1742
    // Check for mergable requests
1743
    num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb);
1744

    
1745
    // Run the aio requests
1746
    for (i = 0; i < num_reqs; i++) {
1747
        acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov,
1748
            reqs[i].nb_sectors, multiwrite_cb, mcb);
1749

    
1750
        if (acb == NULL) {
1751
            // We can only fail the whole thing if no request has been
1752
            // submitted yet. Otherwise we'll wait for the submitted AIOs to
1753
            // complete and report the error in the callback.
1754
            if (mcb->num_requests == 0) {
1755
                reqs[i].error = EIO;
1756
                goto fail;
1757
            } else {
1758
                mcb->error = EIO;
1759
                break;
1760
            }
1761
        } else {
1762
            mcb->num_requests++;
1763
        }
1764
    }
1765

    
1766
    return 0;
1767

    
1768
fail:
1769
    free(mcb);
1770
    return -1;
1771
}
1772

    
1773
BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
1774
        BlockDriverCompletionFunc *cb, void *opaque)
1775
{
1776
    BlockDriver *drv = bs->drv;
1777

    
1778
    if (!drv)
1779
        return NULL;
1780

    
1781
    /*
1782
     * Note that unlike bdrv_flush the driver is reponsible for flushing a
1783
     * backing image if it exists.
1784
     */
1785
    return drv->bdrv_aio_flush(bs, cb, opaque);
1786
}
1787

    
1788
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1789
{
1790
    acb->pool->cancel(acb);
1791
}
1792

    
1793

    
1794
/**************************************************************/
1795
/* async block device emulation */
1796

    
1797
typedef struct BlockDriverAIOCBSync {
1798
    BlockDriverAIOCB common;
1799
    QEMUBH *bh;
1800
    int ret;
1801
    /* vector translation state */
1802
    QEMUIOVector *qiov;
1803
    uint8_t *bounce;
1804
    int is_write;
1805
} BlockDriverAIOCBSync;
1806

    
1807
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1808
{
1809
    BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1810
    qemu_bh_delete(acb->bh);
1811
    acb->bh = NULL;
1812
    qemu_aio_release(acb);
1813
}
1814

    
1815
static AIOPool bdrv_em_aio_pool = {
1816
    .aiocb_size         = sizeof(BlockDriverAIOCBSync),
1817
    .cancel             = bdrv_aio_cancel_em,
1818
};
1819

    
1820
static void bdrv_aio_bh_cb(void *opaque)
1821
{
1822
    BlockDriverAIOCBSync *acb = opaque;
1823

    
1824
    if (!acb->is_write)
1825
        qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size);
1826
    qemu_vfree(acb->bounce);
1827
    acb->common.cb(acb->common.opaque, acb->ret);
1828
    qemu_bh_delete(acb->bh);
1829
    acb->bh = NULL;
1830
    qemu_aio_release(acb);
1831
}
1832

    
1833
static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
1834
                                            int64_t sector_num,
1835
                                            QEMUIOVector *qiov,
1836
                                            int nb_sectors,
1837
                                            BlockDriverCompletionFunc *cb,
1838
                                            void *opaque,
1839
                                            int is_write)
1840

    
1841
{
1842
    BlockDriverAIOCBSync *acb;
1843

    
1844
    acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
1845
    acb->is_write = is_write;
1846
    acb->qiov = qiov;
1847
    acb->bounce = qemu_blockalign(bs, qiov->size);
1848

    
1849
    if (!acb->bh)
1850
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1851

    
1852
    if (is_write) {
1853
        qemu_iovec_to_buffer(acb->qiov, acb->bounce);
1854
        acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
1855
    } else {
1856
        acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
1857
    }
1858

    
1859
    qemu_bh_schedule(acb->bh);
1860

    
1861
    return &acb->common;
1862
}
1863

    
1864
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
1865
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
1866
        BlockDriverCompletionFunc *cb, void *opaque)
1867
{
1868
    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
1869
}
1870

    
1871
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
1872
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
1873
        BlockDriverCompletionFunc *cb, void *opaque)
1874
{
1875
    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
1876
}
1877

    
1878
static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
1879
        BlockDriverCompletionFunc *cb, void *opaque)
1880
{
1881
    BlockDriverAIOCBSync *acb;
1882

    
1883
    acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
1884
    acb->is_write = 1; /* don't bounce in the completion hadler */
1885
    acb->qiov = NULL;
1886
    acb->bounce = NULL;
1887
    acb->ret = 0;
1888

    
1889
    if (!acb->bh)
1890
        acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1891

    
1892
    bdrv_flush(bs);
1893
    qemu_bh_schedule(acb->bh);
1894
    return &acb->common;
1895
}
1896

    
1897
/**************************************************************/
1898
/* sync block device emulation */
1899

    
1900
static void bdrv_rw_em_cb(void *opaque, int ret)
1901
{
1902
    *(int *)opaque = ret;
1903
}
1904

    
1905
#define NOT_DONE 0x7fffffff
1906

    
1907
static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1908
                        uint8_t *buf, int nb_sectors)
1909
{
1910
    int async_ret;
1911
    BlockDriverAIOCB *acb;
1912
    struct iovec iov;
1913
    QEMUIOVector qiov;
1914

    
1915
    async_context_push();
1916

    
1917
    async_ret = NOT_DONE;
1918
    iov.iov_base = (void *)buf;
1919
    iov.iov_len = nb_sectors * 512;
1920
    qemu_iovec_init_external(&qiov, &iov, 1);
1921
    acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors,
1922
        bdrv_rw_em_cb, &async_ret);
1923
    if (acb == NULL) {
1924
        async_ret = -1;
1925
        goto fail;
1926
    }
1927

    
1928
    while (async_ret == NOT_DONE) {
1929
        qemu_aio_wait();
1930
    }
1931

    
1932

    
1933
fail:
1934
    async_context_pop();
1935
    return async_ret;
1936
}
1937

    
1938
static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1939
                         const uint8_t *buf, int nb_sectors)
1940
{
1941
    int async_ret;
1942
    BlockDriverAIOCB *acb;
1943
    struct iovec iov;
1944
    QEMUIOVector qiov;
1945

    
1946
    async_context_push();
1947

    
1948
    async_ret = NOT_DONE;
1949
    iov.iov_base = (void *)buf;
1950
    iov.iov_len = nb_sectors * 512;
1951
    qemu_iovec_init_external(&qiov, &iov, 1);
1952
    acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors,
1953
        bdrv_rw_em_cb, &async_ret);
1954
    if (acb == NULL) {
1955
        async_ret = -1;
1956
        goto fail;
1957
    }
1958
    while (async_ret == NOT_DONE) {
1959
        qemu_aio_wait();
1960
    }
1961

    
1962
fail:
1963
    async_context_pop();
1964
    return async_ret;
1965
}
1966

    
1967
void bdrv_init(void)
1968
{
1969
    module_call_init(MODULE_INIT_BLOCK);
1970
}
1971

    
1972
void bdrv_init_with_whitelist(void)
1973
{
1974
    use_bdrv_whitelist = 1;
1975
    bdrv_init();
1976
}
1977

    
1978
void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
1979
                   BlockDriverCompletionFunc *cb, void *opaque)
1980
{
1981
    BlockDriverAIOCB *acb;
1982

    
1983
    if (pool->free_aiocb) {
1984
        acb = pool->free_aiocb;
1985
        pool->free_aiocb = acb->next;
1986
    } else {
1987
        acb = qemu_mallocz(pool->aiocb_size);
1988
        acb->pool = pool;
1989
    }
1990
    acb->bs = bs;
1991
    acb->cb = cb;
1992
    acb->opaque = opaque;
1993
    return acb;
1994
}
1995

    
1996
void qemu_aio_release(void *p)
1997
{
1998
    BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p;
1999
    AIOPool *pool = acb->pool;
2000
    acb->next = pool->free_aiocb;
2001
    pool->free_aiocb = acb;
2002
}
2003

    
2004
/**************************************************************/
2005
/* removable device support */
2006

    
2007
/**
2008
 * Return TRUE if the media is present
2009
 */
2010
int bdrv_is_inserted(BlockDriverState *bs)
2011
{
2012
    BlockDriver *drv = bs->drv;
2013
    int ret;
2014
    if (!drv)
2015
        return 0;
2016
    if (!drv->bdrv_is_inserted)
2017
        return 1;
2018
    ret = drv->bdrv_is_inserted(bs);
2019
    return ret;
2020
}
2021

    
2022
/**
2023
 * Return TRUE if the media changed since the last call to this
2024
 * function. It is currently only used for floppy disks
2025
 */
2026
int bdrv_media_changed(BlockDriverState *bs)
2027
{
2028
    BlockDriver *drv = bs->drv;
2029
    int ret;
2030

    
2031
    if (!drv || !drv->bdrv_media_changed)
2032
        ret = -ENOTSUP;
2033
    else
2034
        ret = drv->bdrv_media_changed(bs);
2035
    if (ret == -ENOTSUP)
2036
        ret = bs->media_changed;
2037
    bs->media_changed = 0;
2038
    return ret;
2039
}
2040

    
2041
/**
2042
 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
2043
 */
2044
int bdrv_eject(BlockDriverState *bs, int eject_flag)
2045
{
2046
    BlockDriver *drv = bs->drv;
2047
    int ret;
2048

    
2049
    if (bs->locked) {
2050
        return -EBUSY;
2051
    }
2052

    
2053
    if (!drv || !drv->bdrv_eject) {
2054
        ret = -ENOTSUP;
2055
    } else {
2056
        ret = drv->bdrv_eject(bs, eject_flag);
2057
    }
2058
    if (ret == -ENOTSUP) {
2059
        if (eject_flag)
2060
            bdrv_close(bs);
2061
        ret = 0;
2062
    }
2063

    
2064
    return ret;
2065
}
2066

    
2067
int bdrv_is_locked(BlockDriverState *bs)
2068
{
2069
    return bs->locked;
2070
}
2071

    
2072
/**
2073
 * Lock or unlock the media (if it is locked, the user won't be able
2074
 * to eject it manually).
2075
 */
2076
void bdrv_set_locked(BlockDriverState *bs, int locked)
2077
{
2078
    BlockDriver *drv = bs->drv;
2079

    
2080
    bs->locked = locked;
2081
    if (drv && drv->bdrv_set_locked) {
2082
        drv->bdrv_set_locked(bs, locked);
2083
    }
2084
}
2085

    
2086
/* needed for generic scsi interface */
2087

    
2088
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
2089
{
2090
    BlockDriver *drv = bs->drv;
2091

    
2092
    if (drv && drv->bdrv_ioctl)
2093
        return drv->bdrv_ioctl(bs, req, buf);
2094
    return -ENOTSUP;
2095
}
2096

    
2097
BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
2098
        unsigned long int req, void *buf,
2099
        BlockDriverCompletionFunc *cb, void *opaque)
2100
{
2101
    BlockDriver *drv = bs->drv;
2102

    
2103
    if (drv && drv->bdrv_aio_ioctl)
2104
        return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
2105
    return NULL;
2106
}
2107

    
2108

    
2109

    
2110
void *qemu_blockalign(BlockDriverState *bs, size_t size)
2111
{
2112
    return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
2113
}
2114

    
2115
void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable)
2116
{
2117
    int64_t bitmap_size;
2118

    
2119
    if (enable) {
2120
        if (!bs->dirty_bitmap) {
2121
            bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) +
2122
                    BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
2123
            bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
2124

    
2125
            bs->dirty_bitmap = qemu_mallocz(bitmap_size);
2126
        }
2127
    } else {
2128
        if (bs->dirty_bitmap) {
2129
            qemu_free(bs->dirty_bitmap);
2130
            bs->dirty_bitmap = NULL;
2131
        }
2132
    }
2133
}
2134

    
2135
int bdrv_get_dirty(BlockDriverState *bs, int64_t sector)
2136
{
2137
    int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
2138

    
2139
    if (bs->dirty_bitmap &&
2140
        (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) {
2141
        return bs->dirty_bitmap[chunk / (sizeof(unsigned long) * 8)] &
2142
            (1 << (chunk % (sizeof(unsigned long) * 8)));
2143
    } else {
2144
        return 0;
2145
    }
2146
}
2147

    
2148
void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
2149
                      int nr_sectors)
2150
{
2151
    set_dirty_bitmap(bs, cur_sector, nr_sectors, 0);
2152
}