block.c

   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 "vl.h"
  25 #include "block_int.h"
  26
  27 #ifdef _BSD
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <sys/ioctl.h>
  31 #include <sys/queue.h>
  32 #include <sys/disk.h>
  33 #endif
  34
  35 #ifdef CONFIG_COCOA
  36 #include <paths.h>
  37 #include <sys/param.h>
  38 #include <IOKit/IOKitLib.h>
  39 #include <IOKit/IOBSD.h>
  40 #include <IOKit/storage/IOMediaBSDClient.h>
  41 #include <IOKit/storage/IOMedia.h>
  42 #include <IOKit/storage/IOCDMedia.h>
  43 //#include <IOKit/storage/IOCDTypes.h>
  44 #include <CoreFoundation/CoreFoundation.h>
  45 #endif
  46
  47 static BlockDriverState *bdrv_first;
  48 static BlockDriver *first_drv;
  49
  50 #ifdef CONFIG_COCOA
  51 static kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator );
  52 static kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize );
  53
  54 kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator )
  55 {
  56     kern_return_t       kernResult;
  57     mach_port_t     masterPort;
  58     CFMutableDictionaryRef  classesToMatch;
  59
  60     kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort );
  61     if ( KERN_SUCCESS != kernResult ) {
  62         printf( "IOMasterPort returned %d\n", kernResult );
  63     }
  64
  65     classesToMatch = IOServiceMatching( kIOCDMediaClass );
  66     if ( classesToMatch == NULL ) {
  67         printf( "IOServiceMatching returned a NULL dictionary.\n" );
  68     } else {
  69     CFDictionarySetValue( classesToMatch, CFSTR( kIOMediaEjectableKey ), kCFBooleanTrue );
  70     }
  71     kernResult = IOServiceGetMatchingServices( masterPort, classesToMatch, mediaIterator );
  72     if ( KERN_SUCCESS != kernResult )
  73     {
  74         printf( "IOServiceGetMatchingServices returned %d\n", kernResult );
  75     }
  76
  77     return kernResult;
  78 }
  79
  80 kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize )
  81 {
  82     io_object_t     nextMedia;
  83     kern_return_t   kernResult = KERN_FAILURE;
  84     *bsdPath = '\0';
  85     nextMedia = IOIteratorNext( mediaIterator );
  86     if ( nextMedia )
  87     {
  88         CFTypeRef   bsdPathAsCFString;
  89     bsdPathAsCFString = IORegistryEntryCreateCFProperty( nextMedia, CFSTR( kIOBSDNameKey ), kCFAllocatorDefault, 0 );
  90         if ( bsdPathAsCFString ) {
  91             size_t devPathLength;
  92             strcpy( bsdPath, _PATH_DEV );
  93             strcat( bsdPath, "r" );
  94             devPathLength = strlen( bsdPath );
  95             if ( CFStringGetCString( bsdPathAsCFString, bsdPath + devPathLength, maxPathSize - devPathLength, kCFStringEncodingASCII ) ) {
  96                 kernResult = KERN_SUCCESS;
  97             }
  98             CFRelease( bsdPathAsCFString );
  99         }
 100         IOObjectRelease( nextMedia );
 101     }
 102
 103     return kernResult;
 104 }
 105
 106 #endif
 107
 108 void bdrv_register(BlockDriver *bdrv)
 109 {
 110     bdrv->next = first_drv;
 111     first_drv = bdrv;
 112 }
 113
 114 /* create a new block device (by default it is empty) */
 115 BlockDriverState *bdrv_new(const char *device_name)
 116 {
 117     BlockDriverState **pbs, *bs;
 118
 119     bs = qemu_mallocz(sizeof(BlockDriverState));
 120     if(!bs)
 121         return NULL;
 122     pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
 123     if (device_name[0] != '\0') {
 124         /* insert at the end */
 125         pbs = &bdrv_first;
 126         while (*pbs != NULL)
 127             pbs = &(*pbs)->next;
 128         *pbs = bs;
 129     }
 130     return bs;
 131 }
 132
 133 BlockDriver *bdrv_find_format(const char *format_name)
 134 {
 135     BlockDriver *drv1;
 136     for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
 137         if (!strcmp(drv1->format_name, format_name))
 138             return drv1;
 139     }
 140     return NULL;
 141 }
 142
 143 int bdrv_create(BlockDriver *drv,
 144                 const char *filename, int64_t size_in_sectors,
 145                 const char *backing_file, int flags)
 146 {
 147     if (!drv->bdrv_create)
 148         return -ENOTSUP;
 149     return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
 150 }
 151
 152 #ifdef _WIN32
 153 void get_tmp_filename(char *filename, int size)
 154 {
 155     char* p = strrchr(filename, '/');
 156
 157     if (p == NULL)
 158         return;
 159
 160     /* XXX: find a better function */
 161     tmpnam(p);
 162     *p = '/';
 163 }
 164 #else
 165 void get_tmp_filename(char *filename, int size)
 166 {
 167     int fd;
 168     /* XXX: race condition possible */
 169     pstrcpy(filename, size, "/tmp/vl.XXXXXX");
 170     fd = mkstemp(filename);
 171     close(fd);
 172 }
 173 #endif
 174
 175 /* XXX: force raw format if block or character device ? It would
 176    simplify the BSD case */
 177 static BlockDriver *find_image_format(const char *filename)
 178 {
 179     int fd, ret, score, score_max;
 180     BlockDriver *drv1, *drv;
 181     uint8_t *buf;
 182     size_t bufsize = 1024;
 183
 184     fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
 185     if (fd < 0) {
 186         buf = NULL;
 187         ret = 0;
 188     } else {
 189 #ifdef DIOCGSECTORSIZE
 190         {
 191             unsigned int sectorsize = 512;
 192             if (!ioctl(fd, DIOCGSECTORSIZE, &sectorsize) &&
 193                 sectorsize > bufsize)
 194                 bufsize = sectorsize;
 195         }
 196 #endif
 197 #ifdef CONFIG_COCOA
 198         u_int32_t   blockSize = 512;
 199         if ( !ioctl( fd, DKIOCGETBLOCKSIZE, &blockSize ) && blockSize > bufsize) {
 200             bufsize = blockSize;
 201         }
 202 #endif
 203         buf = qemu_malloc(bufsize);
 204         if (!buf)
 205             return NULL;
 206         ret = read(fd, buf, bufsize);
 207         if (ret < 0) {
 208             close(fd);
 209             qemu_free(buf);
 210             return NULL;
 211         }
 212         close(fd);
 213     }
 214
 215     drv = NULL;
 216     score_max = 0;
 217     for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
 218         score = drv1->bdrv_probe(buf, ret, filename);
 219         if (score > score_max) {
 220             score_max = score;
 221             drv = drv1;
 222         }
 223     }
 224     qemu_free(buf);
 225     return drv;
 226 }
 227
 228 int bdrv_open(BlockDriverState *bs, const char *filename, int snapshot)
 229 {
 230 #ifdef CONFIG_COCOA
 231     if ( strncmp( filename, "/dev/cdrom", 10 ) == 0 ) {
 232         kern_return_t kernResult;
 233         io_iterator_t mediaIterator;
 234         char bsdPath[ MAXPATHLEN ];
 235         int fd;
 236
 237         kernResult = FindEjectableCDMedia( &mediaIterator );
 238         kernResult = GetBSDPath( mediaIterator, bsdPath, sizeof( bsdPath ) );
 239
 240         if ( bsdPath[ 0 ] != '\0' ) {
 241             strcat(bsdPath,"s0");
 242             /* some CDs don't have a partition 0 */
 243             fd = open(bsdPath, O_RDONLY | O_BINARY | O_LARGEFILE);
 244             if (fd < 0) {
 245                 bsdPath[strlen(bsdPath)-1] = '1';
 246             } else {
 247                 close(fd);
 248             }
 249             filename = bsdPath;
 250         }
 251
 252         if ( mediaIterator )
 253             IOObjectRelease( mediaIterator );
 254     }
 255 #endif
 256     return bdrv_open2(bs, filename, snapshot, NULL);
 257 }
 258
 259 int bdrv_open2(BlockDriverState *bs, const char *filename, int snapshot,
 260                BlockDriver *drv)
 261 {
 262     int ret;
 263     char tmp_filename[1024];
 264
 265     bs->read_only = 0;
 266     bs->is_temporary = 0;
 267     bs->encrypted = 0;
 268
 269     if (snapshot) {
 270         BlockDriverState *bs1;
 271         int64_t total_size;
 272
 273         /* if snapshot, we create a temporary backing file and open it
 274            instead of opening 'filename' directly */
 275
 276         /* if there is a backing file, use it */
 277         bs1 = bdrv_new("");
 278         if (!bs1) {
 279             return -1;
 280         }
 281         if (bdrv_open(bs1, filename, 0) < 0) {
 282             bdrv_delete(bs1);
 283             return -1;
 284         }
 285         total_size = bs1->total_sectors;
 286         bdrv_delete(bs1);
 287
 288         get_tmp_filename(tmp_filename, sizeof(tmp_filename));
 289         /* XXX: use cow for linux as it is more efficient ? */
 290         if (bdrv_create(&bdrv_qcow, tmp_filename,
 291                         total_size, filename, 0) < 0) {
 292             return -1;
 293         }
 294         filename = tmp_filename;
 295         bs->is_temporary = 1;
 296     }
 297
 298     pstrcpy(bs->filename, sizeof(bs->filename), filename);
 299     if (!drv) {
 300         drv = find_image_format(filename);
 301         if (!drv)
 302             return -1;
 303     }
 304     bs->drv = drv;
 305     bs->opaque = qemu_mallocz(drv->instance_size);
 306     if (bs->opaque == NULL && drv->instance_size > 0)
 307         return -1;
 308
 309     ret = drv->bdrv_open(bs, filename);
 310     if (ret < 0) {
 311         qemu_free(bs->opaque);
 312         return -1;
 313     }
 314 #ifndef _WIN32
 315     if (bs->is_temporary) {
 316         unlink(filename);
 317     }
 318 #endif
 319     if (bs->backing_file[0] != '\0' && drv->bdrv_is_allocated) {
 320         /* if there is a backing file, use it */
 321         bs->backing_hd = bdrv_new("");
 322         if (!bs->backing_hd) {
 323         fail:
 324             bdrv_close(bs);
 325             return -1;
 326         }
 327         if (bdrv_open(bs->backing_hd, bs->backing_file, 0) < 0)
 328             goto fail;
 329     }
 330
 331     bs->inserted = 1;
 332
 333     /* call the change callback */
 334     if (bs->change_cb)
 335         bs->change_cb(bs->change_opaque);
 336
 337     return 0;
 338 }
 339
 340 void bdrv_close(BlockDriverState *bs)
 341 {
 342     if (bs->inserted) {
 343         if (bs->backing_hd)
 344             bdrv_delete(bs->backing_hd);
 345         bs->drv->bdrv_close(bs);
 346         qemu_free(bs->opaque);
 347 #ifdef _WIN32
 348         if (bs->is_temporary) {
 349             unlink(bs->filename);
 350         }
 351 #endif
 352         bs->opaque = NULL;
 353         bs->drv = NULL;
 354         bs->inserted = 0;
 355
 356         /* call the change callback */
 357         if (bs->change_cb)
 358             bs->change_cb(bs->change_opaque);
 359     }
 360 }
 361
 362 void bdrv_delete(BlockDriverState *bs)
 363 {
 364     /* XXX: remove the driver list */
 365     bdrv_close(bs);
 366     qemu_free(bs);
 367 }
 368
 369 /* commit COW file into the raw image */
 370 int bdrv_commit(BlockDriverState *bs)
 371 {
 372     int64_t i;
 373     int n, j;
 374     unsigned char sector[512];
 375
 376     if (!bs->inserted)
 377         return -ENOENT;
 378
 379     if (bs->read_only) {
 380         return -EACCES;
 381     }
 382
 383     if (!bs->backing_hd) {
 384         return -ENOTSUP;
 385     }
 386
 387     for (i = 0; i < bs->total_sectors;) {
 388         if (bs->drv->bdrv_is_allocated(bs, i, 65536, &n)) {
 389             for(j = 0; j < n; j++) {
 390                 if (bdrv_read(bs, i, sector, 1) != 0) {
 391                     return -EIO;
 392                 }
 393
 394                 if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
 395                     return -EIO;
 396                 }
 397                 i++;
 398             }
 399         } else {
 400             i += n;
 401         }
 402     }
 403
 404     if (bs->drv->bdrv_make_empty)
 405         return bs->drv->bdrv_make_empty(bs);
 406
 407     return 0;
 408 }
 409
 410 /* return -1 if error */
 411 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
 412               uint8_t *buf, int nb_sectors)
 413 {
 414     int ret, n;
 415     BlockDriver *drv = bs->drv;
 416
 417     if (!bs->inserted)
 418         return -1;
 419
 420     while (nb_sectors > 0) {
 421         if (sector_num == 0 && bs->boot_sector_enabled) {
 422             memcpy(buf, bs->boot_sector_data, 512);
 423             n = 1;
 424         } else if (bs->backing_hd) {
 425             if (drv->bdrv_is_allocated(bs, sector_num, nb_sectors, &n)) {
 426                 ret = drv->bdrv_read(bs, sector_num, buf, n);
 427                 if (ret < 0)
 428                     return -1;
 429             } else {
 430                 /* read from the base image */
 431                 ret = bdrv_read(bs->backing_hd, sector_num, buf, n);
 432                 if (ret < 0)
 433                     return -1;
 434             }
 435         } else {
 436             ret = drv->bdrv_read(bs, sector_num, buf, nb_sectors);
 437             if (ret < 0)
 438                 return -1;
 439             /* no need to loop */
 440             break;
 441         }
 442         nb_sectors -= n;
 443         sector_num += n;
 444         buf += n * 512;
 445     }
 446     return 0;
 447 }
 448
 449 /* return -1 if error */
 450 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
 451                const uint8_t *buf, int nb_sectors)
 452 {
 453     if (!bs->inserted)
 454         return -1;
 455     if (bs->read_only)
 456         return -1;
 457     if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
 458         memcpy(bs->boot_sector_data, buf, 512);
 459     }
 460     return bs->drv->bdrv_write(bs, sector_num, buf, nb_sectors);
 461 }
 462
 463 void bdrv_get_geometry(BlockDriverState *bs, int64_t *nb_sectors_ptr)
 464 {
 465     *nb_sectors_ptr = bs->total_sectors;
 466 }
 467
 468 /* force a given boot sector. */
 469 void bdrv_set_boot_sector(BlockDriverState *bs, const uint8_t *data, int size)
 470 {
 471     bs->boot_sector_enabled = 1;
 472     if (size > 512)
 473         size = 512;
 474     memcpy(bs->boot_sector_data, data, size);
 475     memset(bs->boot_sector_data + size, 0, 512 - size);
 476 }
 477
 478 void bdrv_set_geometry_hint(BlockDriverState *bs,
 479                             int cyls, int heads, int secs)
 480 {
 481     bs->cyls = cyls;
 482     bs->heads = heads;
 483     bs->secs = secs;
 484 }
 485
 486 void bdrv_set_type_hint(BlockDriverState *bs, int type)
 487 {
 488     bs->type = type;
 489     bs->removable = ((type == BDRV_TYPE_CDROM ||
 490                       type == BDRV_TYPE_FLOPPY));
 491 }
 492
 493 void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
 494 {
 495     bs->translation = translation;
 496 }
 497
 498 void bdrv_get_geometry_hint(BlockDriverState *bs,
 499                             int *pcyls, int *pheads, int *psecs)
 500 {
 501     *pcyls = bs->cyls;
 502     *pheads = bs->heads;
 503     *psecs = bs->secs;
 504 }
 505
 506 int bdrv_get_type_hint(BlockDriverState *bs)
 507 {
 508     return bs->type;
 509 }
 510
 511 int bdrv_get_translation_hint(BlockDriverState *bs)
 512 {
 513     return bs->translation;
 514 }
 515
 516 int bdrv_is_removable(BlockDriverState *bs)
 517 {
 518     return bs->removable;
 519 }
 520
 521 int bdrv_is_read_only(BlockDriverState *bs)
 522 {
 523     return bs->read_only;
 524 }
 525
 526 int bdrv_is_inserted(BlockDriverState *bs)
 527 {
 528     return bs->inserted;
 529 }
 530
 531 int bdrv_is_locked(BlockDriverState *bs)
 532 {
 533     return bs->locked;
 534 }
 535
 536 void bdrv_set_locked(BlockDriverState *bs, int locked)
 537 {
 538     bs->locked = locked;
 539 }
 540
 541 void bdrv_set_change_cb(BlockDriverState *bs,
 542                         void (*change_cb)(void *opaque), void *opaque)
 543 {
 544     bs->change_cb = change_cb;
 545     bs->change_opaque = opaque;
 546 }
 547
 548 int bdrv_is_encrypted(BlockDriverState *bs)
 549 {
 550     if (bs->backing_hd && bs->backing_hd->encrypted)
 551         return 1;
 552     return bs->encrypted;
 553 }
 554
 555 int bdrv_set_key(BlockDriverState *bs, const char *key)
 556 {
 557     int ret;
 558     if (bs->backing_hd && bs->backing_hd->encrypted) {
 559         ret = bdrv_set_key(bs->backing_hd, key);
 560         if (ret < 0)
 561             return ret;
 562         if (!bs->encrypted)
 563             return 0;
 564     }
 565     if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
 566         return -1;
 567     return bs->drv->bdrv_set_key(bs, key);
 568 }
 569
 570 void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
 571 {
 572     if (!bs->inserted || !bs->drv) {
 573         buf[0] = '\0';
 574     } else {
 575         pstrcpy(buf, buf_size, bs->drv->format_name);
 576     }
 577 }
 578
 579 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
 580                          void *opaque)
 581 {
 582     BlockDriver *drv;
 583
 584     for (drv = first_drv; drv != NULL; drv = drv->next) {
 585         it(opaque, drv->format_name);
 586     }
 587 }
 588
 589 BlockDriverState *bdrv_find(const char *name)
 590 {
 591     BlockDriverState *bs;
 592
 593     for (bs = bdrv_first; bs != NULL; bs = bs->next) {
 594         if (!strcmp(name, bs->device_name))
 595             return bs;
 596     }
 597     return NULL;
 598 }
 599
 600 void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque)
 601 {
 602     BlockDriverState *bs;
 603
 604     for (bs = bdrv_first; bs != NULL; bs = bs->next) {
 605         it(opaque, bs->device_name);
 606     }
 607 }
 608
 609 const char *bdrv_get_device_name(BlockDriverState *bs)
 610 {
 611     return bs->device_name;
 612 }
 613
 614 void bdrv_info(void)
 615 {
 616     BlockDriverState *bs;
 617
 618     for (bs = bdrv_first; bs != NULL; bs = bs->next) {
 619         term_printf("%s:", bs->device_name);
 620         term_printf(" type=");
 621         switch(bs->type) {
 622         case BDRV_TYPE_HD:
 623             term_printf("hd");
 624             break;
 625         case BDRV_TYPE_CDROM:
 626             term_printf("cdrom");
 627             break;
 628         case BDRV_TYPE_FLOPPY:
 629             term_printf("floppy");
 630             break;
 631         }
 632         term_printf(" removable=%d", bs->removable);
 633         if (bs->removable) {
 634             term_printf(" locked=%d", bs->locked);
 635         }
 636         if (bs->inserted) {
 637             term_printf(" file=%s", bs->filename);
 638             if (bs->backing_file[0] != '\0')
 639                 term_printf(" backing_file=%s", bs->backing_file);
 640             term_printf(" ro=%d", bs->read_only);
 641             term_printf(" drv=%s", bs->drv->format_name);
 642             if (bs->encrypted)
 643                 term_printf(" encrypted");
 644         } else {
 645             term_printf(" [not inserted]");
 646         }
 647         term_printf("\n");
 648     }
 649 }
 650
 651
 652 /**************************************************************/
 653 /* RAW block driver */
 654
 655 typedef struct BDRVRawState {
 656     int fd;
 657 } BDRVRawState;
 658
 659 static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
 660 {
 661     return 1; /* maybe */
 662 }
 663
 664 static int raw_open(BlockDriverState *bs, const char *filename)
 665 {
 666     BDRVRawState *s = bs->opaque;
 667     int fd;
 668     int64_t size;
 669 #ifdef _BSD
 670     struct stat sb;
 671 #endif
 672
 673     fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE);
 674     if (fd < 0) {
 675         fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
 676         if (fd < 0)
 677             return -1;
 678         bs->read_only = 1;
 679     }
 680 #ifdef _BSD
 681     if (!fstat(fd, &sb) && (S_IFCHR & sb.st_mode)) {
 682 #ifdef DIOCGMEDIASIZE
 683         if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size))
 684 #endif
 685 #ifdef CONFIG_COCOA
 686         size = LONG_LONG_MAX;
 687 #else
 688         size = lseek(fd, 0LL, SEEK_END);
 689 #endif
 690     } else
 691 #endif
 692     {
 693         size = lseek(fd, 0, SEEK_END);
 694     }
 695 #ifdef _WIN32
 696     /* On Windows hosts it can happen that we're unable to get file size
 697        for CD-ROM raw device (it's inherent limitation of the CDFS driver). */
 698     if (size == -1)
 699         size = LONG_LONG_MAX;
 700 #endif
 701     bs->total_sectors = size / 512;
 702     s->fd = fd;
 703     return 0;
 704 }
 705
 706 static int raw_read(BlockDriverState *bs, int64_t sector_num,
 707                     uint8_t *buf, int nb_sectors)
 708 {
 709     BDRVRawState *s = bs->opaque;
 710     int ret;
 711
 712     lseek(s->fd, sector_num * 512, SEEK_SET);
 713     ret = read(s->fd, buf, nb_sectors * 512);
 714     if (ret != nb_sectors * 512)
 715         return -1;
 716     return 0;
 717 }
 718
 719 static int raw_write(BlockDriverState *bs, int64_t sector_num,
 720                      const uint8_t *buf, int nb_sectors)
 721 {
 722     BDRVRawState *s = bs->opaque;
 723     int ret;
 724
 725     lseek(s->fd, sector_num * 512, SEEK_SET);
 726     ret = write(s->fd, buf, nb_sectors * 512);
 727     if (ret != nb_sectors * 512)
 728         return -1;
 729     return 0;
 730 }
 731
 732 static void raw_close(BlockDriverState *bs)
 733 {
 734     BDRVRawState *s = bs->opaque;
 735     close(s->fd);
 736 }
 737
 738 static int raw_create(const char *filename, int64_t total_size,
 739                       const char *backing_file, int flags)
 740 {
 741     int fd;
 742
 743     if (flags || backing_file)
 744         return -ENOTSUP;
 745
 746     fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
 747               0644);
 748     if (fd < 0)
 749         return -EIO;
 750     ftruncate(fd, total_size * 512);
 751     close(fd);
 752     return 0;
 753 }
 754
 755 BlockDriver bdrv_raw = {
 756     "raw",
 757     sizeof(BDRVRawState),
 758     raw_probe,
 759     raw_open,
 760     raw_read,
 761     raw_write,
 762     raw_close,
 763     raw_create,
 764 };
 765
 766 void bdrv_init(void)
 767 {
 768     bdrv_register(&bdrv_raw);
 769 #ifndef _WIN32
 770     bdrv_register(&bdrv_cow);
 771 #endif
 772     bdrv_register(&bdrv_qcow);
 773     bdrv_register(&bdrv_vmdk);
 774     bdrv_register(&bdrv_cloop);
 775     bdrv_register(&bdrv_dmg);
 776     bdrv_register(&bdrv_bochs);
 777     bdrv_register(&bdrv_vpc);
 778     bdrv_register(&bdrv_vvfat);
 779 }