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 #define SECTOR_BITS 9
  36 #define SECTOR_SIZE (1 << SECTOR_BITS)
  37
  38 typedef struct BlockDriverAIOCBSync {
  39     BlockDriverAIOCB common;
  40     QEMUBH *bh;
  41     int ret;
  42 } BlockDriverAIOCBSync;
  43
  44 static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
  45         int64_t sector_num, uint8_t *buf, int nb_sectors,
  46         BlockDriverCompletionFunc *cb, void *opaque);
  47 static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
  48         int64_t sector_num, const uint8_t *buf, int nb_sectors,
  49         BlockDriverCompletionFunc *cb, void *opaque);
  50 static void bdrv_aio_cancel_em(BlockDriverAIOCB *acb);
  51 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
  52                         uint8_t *buf, int nb_sectors);
  53 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
  54                          const uint8_t *buf, int nb_sectors);
  55
  56 static BlockDriverState *bdrv_first;
  57 static BlockDriver *first_drv;
  58
  59 #ifdef _WIN32
  60 #define PATH_SEP '\\'
  61 #else
  62 #define PATH_SEP '/'
  63 #endif
  64
  65 int path_is_absolute(const char *path)
  66 {
  67     const char *p;
  68     p = strchr(path, ':');
  69     if (p)
  70         p++;
  71     else
  72         p = path;
  73     return (*p == PATH_SEP);
  74 }
  75
  76 /* if filename is absolute, just copy it to dest. Otherwise, build a
  77    path to it by considering it is relative to base_path. URL are
  78    supported. */
  79 void path_combine(char *dest, int dest_size,
  80                   const char *base_path,
  81                   const char *filename)
  82 {
  83     const char *p, *p1;
  84     int len;
  85
  86     if (dest_size <= 0)
  87         return;
  88     if (path_is_absolute(filename)) {
  89         pstrcpy(dest, dest_size, filename);
  90     } else {
  91         p = strchr(base_path, ':');
  92         if (p)
  93             p++;
  94         else
  95             p = base_path;
  96         p1 = strrchr(base_path, PATH_SEP);
  97         if (p1)
  98             p1++;
  99         else
 100             p1 = base_path;
 101         if (p1 > p)
 102             p = p1;
 103         len = p - base_path;
 104         if (len > dest_size - 1)
 105             len = dest_size - 1;
 106         memcpy(dest, base_path, len);
 107         dest[len] = '\0';
 108         pstrcat(dest, dest_size, filename);
 109     }
 110 }
 111
 112
 113 void bdrv_register(BlockDriver *bdrv)
 114 {
 115     if (!bdrv->bdrv_aio_read) {
 116         /* add AIO emulation layer */
 117         bdrv->bdrv_aio_read = bdrv_aio_read_em;
 118         bdrv->bdrv_aio_write = bdrv_aio_write_em;
 119         bdrv->bdrv_aio_cancel = bdrv_aio_cancel_em;
 120         bdrv->aiocb_size = sizeof(BlockDriverAIOCBSync);
 121     } else if (!bdrv->bdrv_read && !bdrv->bdrv_pread) {
 122         /* add synchronous IO emulation layer */
 123         bdrv->bdrv_read = bdrv_read_em;
 124         bdrv->bdrv_write = bdrv_write_em;
 125     }
 126     bdrv->next = first_drv;
 127     first_drv = bdrv;
 128 }
 129
 130 /* create a new block device (by default it is empty) */
 131 BlockDriverState *bdrv_new(const char *device_name)
 132 {
 133     BlockDriverState **pbs, *bs;
 134
 135     bs = qemu_mallocz(sizeof(BlockDriverState));
 136     if(!bs)
 137         return NULL;
 138     pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
 139     if (device_name[0] != '\0') {
 140         /* insert at the end */
 141         pbs = &bdrv_first;
 142         while (*pbs != NULL)
 143             pbs = &(*pbs)->next;
 144         *pbs = bs;
 145     }
 146     return bs;
 147 }
 148
 149 BlockDriver *bdrv_find_format(const char *format_name)
 150 {
 151     BlockDriver *drv1;
 152     for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
 153         if (!strcmp(drv1->format_name, format_name))
 154             return drv1;
 155     }
 156     return NULL;
 157 }
 158
 159 int bdrv_create(BlockDriver *drv,
 160                 const char *filename, int64_t size_in_sectors,
 161                 const char *backing_file, int flags)
 162 {
 163     if (!drv->bdrv_create)
 164         return -ENOTSUP;
 165     return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
 166 }
 167
 168 #ifdef _WIN32
 169 void get_tmp_filename(char *filename, int size)
 170 {
 171     tmpnam(filename);
 172 }
 173 #else
 174 void get_tmp_filename(char *filename, int size)
 175 {
 176     int fd;
 177     /* XXX: race condition possible */
 178     pstrcpy(filename, size, "/tmp/vl.XXXXXX");
 179     fd = mkstemp(filename);
 180     close(fd);
 181 }
 182 #endif
 183
 184 #ifdef _WIN32
 185 static int is_windows_drive_prefix(const char *filename)
 186 {
 187     return (((filename[0] >= 'a' && filename[0] <= 'z') ||
 188              (filename[0] >= 'A' && filename[0] <= 'Z')) &&
 189             filename[1] == ':');
 190 }
 191
 192 static int is_windows_drive(const char *filename)
 193 {
 194     if (is_windows_drive_prefix(filename) &&
 195         filename[2] == '\0')
 196         return 1;
 197     if (strstart(filename, "\\\\.\\", NULL) ||
 198         strstart(filename, "//./", NULL))
 199         return 1;
 200     return 0;
 201 }
 202 #endif
 203
 204 static BlockDriver *find_protocol(const char *filename)
 205 {
 206     BlockDriver *drv1;
 207     char protocol[128];
 208     int len;
 209     const char *p;
 210
 211 #ifdef _WIN32
 212     if (is_windows_drive(filename) ||
 213         is_windows_drive_prefix(filename))
 214         return &bdrv_raw;
 215 #endif
 216     p = strchr(filename, ':');
 217     if (!p)
 218         return &bdrv_raw;
 219     len = p - filename;
 220     if (len > sizeof(protocol) - 1)
 221         len = sizeof(protocol) - 1;
 222     memcpy(protocol, filename, len);
 223     protocol[len] = '\0';
 224     for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
 225         if (drv1->protocol_name &&
 226             !strcmp(drv1->protocol_name, protocol))
 227             return drv1;
 228     }
 229     return NULL;
 230 }
 231
 232 /* XXX: force raw format if block or character device ? It would
 233    simplify the BSD case */
 234 static BlockDriver *find_image_format(const char *filename)
 235 {
 236     int ret, score, score_max;
 237     BlockDriver *drv1, *drv;
 238     uint8_t buf[2048];
 239     BlockDriverState *bs;
 240
 241     /* detect host devices. By convention, /dev/cdrom[N] is always
 242        recognized as a host CDROM */
 243     if (strstart(filename, "/dev/cdrom", NULL))
 244         return &bdrv_host_device;
 245 #ifdef _WIN32
 246     if (is_windows_drive(filename))
 247         return &bdrv_host_device;
 248 #else
 249     {
 250         struct stat st;
 251         if (stat(filename, &st) >= 0 &&
 252             (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
 253             return &bdrv_host_device;
 254         }
 255     }
 256 #endif
 257
 258     drv = find_protocol(filename);
 259     /* no need to test disk image formats for vvfat */
 260     if (drv == &bdrv_vvfat)
 261         return drv;
 262
 263     ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
 264     if (ret < 0)
 265         return NULL;
 266     ret = bdrv_pread(bs, 0, buf, sizeof(buf));
 267     bdrv_delete(bs);
 268     if (ret < 0) {
 269         return NULL;
 270     }
 271
 272     score_max = 0;
 273     for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
 274         if (drv1->bdrv_probe) {
 275             score = drv1->bdrv_probe(buf, ret, filename);
 276             if (score > score_max) {
 277                 score_max = score;
 278                 drv = drv1;
 279             }
 280         }
 281     }
 282     return drv;
 283 }
 284
 285 int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
 286 {
 287     BlockDriverState *bs;
 288     int ret;
 289
 290     bs = bdrv_new("");
 291     if (!bs)
 292         return -ENOMEM;
 293     ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL);
 294     if (ret < 0) {
 295         bdrv_delete(bs);
 296         return ret;
 297     }
 298     *pbs = bs;
 299     return 0;
 300 }
 301
 302 int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
 303 {
 304     return bdrv_open2(bs, filename, flags, NULL);
 305 }
 306
 307 int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
 308                BlockDriver *drv)
 309 {
 310     int ret, open_flags;
 311     char tmp_filename[1024];
 312     char backing_filename[1024];
 313
 314     bs->read_only = 0;
 315     bs->is_temporary = 0;
 316     bs->encrypted = 0;
 317
 318     if (flags & BDRV_O_SNAPSHOT) {
 319         BlockDriverState *bs1;
 320         int64_t total_size;
 321
 322         /* if snapshot, we create a temporary backing file and open it
 323            instead of opening 'filename' directly */
 324
 325         /* if there is a backing file, use it */
 326         bs1 = bdrv_new("");
 327         if (!bs1) {
 328             return -ENOMEM;
 329         }
 330         if (bdrv_open(bs1, filename, 0) < 0) {
 331             bdrv_delete(bs1);
 332             return -1;
 333         }
 334         total_size = bdrv_getlength(bs1) >> SECTOR_BITS;
 335         bdrv_delete(bs1);
 336
 337         get_tmp_filename(tmp_filename, sizeof(tmp_filename));
 338         realpath(filename, backing_filename);
 339         if (bdrv_create(&bdrv_qcow2, tmp_filename,
 340                         total_size, backing_filename, 0) < 0) {
 341             return -1;
 342         }
 343         filename = tmp_filename;
 344         bs->is_temporary = 1;
 345     }
 346
 347     pstrcpy(bs->filename, sizeof(bs->filename), filename);
 348     if (flags & BDRV_O_FILE) {
 349         drv = find_protocol(filename);
 350         if (!drv)
 351             return -ENOENT;
 352     } else {
 353         if (!drv) {
 354             drv = find_image_format(filename);
 355             if (!drv)
 356                 return -1;
 357         }
 358     }
 359     bs->drv = drv;
 360     bs->opaque = qemu_mallocz(drv->instance_size);
 361     if (bs->opaque == NULL && drv->instance_size > 0)
 362         return -1;
 363     /* Note: for compatibility, we open disk image files as RDWR, and
 364        RDONLY as fallback */
 365     if (!(flags & BDRV_O_FILE))
 366         open_flags = BDRV_O_RDWR;
 367     else
 368         open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
 369     ret = drv->bdrv_open(bs, filename, open_flags);
 370     if (ret == -EACCES && !(flags & BDRV_O_FILE)) {
 371         ret = drv->bdrv_open(bs, filename, BDRV_O_RDONLY);
 372         bs->read_only = 1;
 373     }
 374     if (ret < 0) {
 375         qemu_free(bs->opaque);
 376         bs->opaque = NULL;
 377         bs->drv = NULL;
 378         return ret;
 379     }
 380     if (drv->bdrv_getlength) {
 381         bs->total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
 382     }
 383 #ifndef _WIN32
 384     if (bs->is_temporary) {
 385         unlink(filename);
 386     }
 387 #endif
 388     if (bs->backing_file[0] != '\0') {
 389         /* if there is a backing file, use it */
 390         bs->backing_hd = bdrv_new("");
 391         if (!bs->backing_hd) {
 392         fail:
 393             bdrv_close(bs);
 394             return -ENOMEM;
 395         }
 396         path_combine(backing_filename, sizeof(backing_filename),
 397                      filename, bs->backing_file);
 398         if (bdrv_open(bs->backing_hd, backing_filename, 0) < 0)
 399             goto fail;
 400     }
 401
 402     /* call the change callback */
 403     bs->media_changed = 1;
 404     if (bs->change_cb)
 405         bs->change_cb(bs->change_opaque);
 406
 407     return 0;
 408 }
 409
 410 void bdrv_close(BlockDriverState *bs)
 411 {
 412     if (bs->drv) {
 413         if (bs->backing_hd)
 414             bdrv_delete(bs->backing_hd);
 415         bs->drv->bdrv_close(bs);
 416         qemu_free(bs->opaque);
 417 #ifdef _WIN32
 418         if (bs->is_temporary) {
 419             unlink(bs->filename);
 420         }
 421 #endif
 422         bs->opaque = NULL;
 423         bs->drv = NULL;
 424
 425         /* call the change callback */
 426         bs->media_changed = 1;
 427         if (bs->change_cb)
 428             bs->change_cb(bs->change_opaque);
 429     }
 430 }
 431
 432 void bdrv_delete(BlockDriverState *bs)
 433 {
 434     /* XXX: remove the driver list */
 435     bdrv_close(bs);
 436     qemu_free(bs);
 437 }
 438
 439 /* commit COW file into the raw image */
 440 int bdrv_commit(BlockDriverState *bs)
 441 {
 442     BlockDriver *drv = bs->drv;
 443     int64_t i, total_sectors;
 444     int n, j;
 445     unsigned char sector[512];
 446
 447     if (!drv)
 448         return -ENOMEDIUM;
 449
 450     if (bs->read_only) {
 451         return -EACCES;
 452     }
 453
 454     if (!bs->backing_hd) {
 455         return -ENOTSUP;
 456     }
 457
 458     total_sectors = bdrv_getlength(bs) >> SECTOR_BITS;
 459     for (i = 0; i < total_sectors;) {
 460         if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
 461             for(j = 0; j < n; j++) {
 462                 if (bdrv_read(bs, i, sector, 1) != 0) {
 463                     return -EIO;
 464                 }
 465
 466                 if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
 467                     return -EIO;
 468                 }
 469                 i++;
 470             }
 471         } else {
 472             i += n;
 473         }
 474     }
 475
 476     if (drv->bdrv_make_empty)
 477         return drv->bdrv_make_empty(bs);
 478
 479     return 0;
 480 }
 481
 482 /* return < 0 if error. See bdrv_write() for the return codes */
 483 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
 484               uint8_t *buf, int nb_sectors)
 485 {
 486     BlockDriver *drv = bs->drv;
 487
 488     if (!drv)
 489         return -ENOMEDIUM;
 490
 491     if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
 492             memcpy(buf, bs->boot_sector_data, 512);
 493         sector_num++;
 494         nb_sectors--;
 495         buf += 512;
 496         if (nb_sectors == 0)
 497             return 0;
 498     }
 499     if (drv->bdrv_pread) {
 500         int ret, len;
 501         len = nb_sectors * 512;
 502         ret = drv->bdrv_pread(bs, sector_num * 512, buf, len);
 503         if (ret < 0)
 504             return ret;
 505         else if (ret != len)
 506             return -EINVAL;
 507         else
 508             return 0;
 509     } else {
 510         return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
 511     }
 512 }
 513
 514 /* Return < 0 if error. Important errors are:
 515   -EIO         generic I/O error (may happen for all errors)
 516   -ENOMEDIUM   No media inserted.
 517   -EINVAL      Invalid sector number or nb_sectors
 518   -EACCES      Trying to write a read-only device
 519 */
 520 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
 521                const uint8_t *buf, int nb_sectors)
 522 {
 523     BlockDriver *drv = bs->drv;
 524     if (!bs->drv)
 525         return -ENOMEDIUM;
 526     if (bs->read_only)
 527         return -EACCES;
 528     if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
 529         memcpy(bs->boot_sector_data, buf, 512);
 530     }
 531     if (drv->bdrv_pwrite) {
 532         int ret, len;
 533         len = nb_sectors * 512;
 534         ret = drv->bdrv_pwrite(bs, sector_num * 512, buf, len);
 535         if (ret < 0)
 536             return ret;
 537         else if (ret != len)
 538             return -EIO;
 539         else
 540             return 0;
 541     } else {
 542         return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
 543     }
 544 }
 545
 546 static int bdrv_pread_em(BlockDriverState *bs, int64_t offset,
 547                          uint8_t *buf, int count1)
 548 {
 549     uint8_t tmp_buf[SECTOR_SIZE];
 550     int len, nb_sectors, count;
 551     int64_t sector_num;
 552
 553     count = count1;
 554     /* first read to align to sector start */
 555     len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
 556     if (len > count)
 557         len = count;
 558     sector_num = offset >> SECTOR_BITS;
 559     if (len > 0) {
 560         if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
 561             return -EIO;
 562         memcpy(buf, tmp_buf + (offset & (SECTOR_SIZE - 1)), len);
 563         count -= len;
 564         if (count == 0)
 565             return count1;
 566         sector_num++;
 567         buf += len;
 568     }
 569
 570     /* read the sectors "in place" */
 571     nb_sectors = count >> SECTOR_BITS;
 572     if (nb_sectors > 0) {
 573         if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0)
 574             return -EIO;
 575         sector_num += nb_sectors;
 576         len = nb_sectors << SECTOR_BITS;
 577         buf += len;
 578         count -= len;
 579     }
 580
 581     /* add data from the last sector */
 582     if (count > 0) {
 583         if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
 584             return -EIO;
 585         memcpy(buf, tmp_buf, count);
 586     }
 587     return count1;
 588 }
 589
 590 static int bdrv_pwrite_em(BlockDriverState *bs, int64_t offset,
 591                           const uint8_t *buf, int count1)
 592 {
 593     uint8_t tmp_buf[SECTOR_SIZE];
 594     int len, nb_sectors, count;
 595     int64_t sector_num;
 596
 597     count = count1;
 598     /* first write to align to sector start */
 599     len = (SECTOR_SIZE - offset) & (SECTOR_SIZE - 1);
 600     if (len > count)
 601         len = count;
 602     sector_num = offset >> SECTOR_BITS;
 603     if (len > 0) {
 604         if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
 605             return -EIO;
 606         memcpy(tmp_buf + (offset & (SECTOR_SIZE - 1)), buf, len);
 607         if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
 608             return -EIO;
 609         count -= len;
 610         if (count == 0)
 611             return count1;
 612         sector_num++;
 613         buf += len;
 614     }
 615
 616     /* write the sectors "in place" */
 617     nb_sectors = count >> SECTOR_BITS;
 618     if (nb_sectors > 0) {
 619         if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0)
 620             return -EIO;
 621         sector_num += nb_sectors;
 622         len = nb_sectors << SECTOR_BITS;
 623         buf += len;
 624         count -= len;
 625     }
 626
 627     /* add data from the last sector */
 628     if (count > 0) {
 629         if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0)
 630             return -EIO;
 631         memcpy(tmp_buf, buf, count);
 632         if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0)
 633             return -EIO;
 634     }
 635     return count1;
 636 }
 637
 638 /**
 639  * Read with byte offsets (needed only for file protocols)
 640  */
 641 int bdrv_pread(BlockDriverState *bs, int64_t offset,
 642                void *buf1, int count1)
 643 {
 644     BlockDriver *drv = bs->drv;
 645
 646     if (!drv)
 647         return -ENOMEDIUM;
 648     if (!drv->bdrv_pread)
 649         return bdrv_pread_em(bs, offset, buf1, count1);
 650     return drv->bdrv_pread(bs, offset, buf1, count1);
 651 }
 652
 653 /**
 654  * Write with byte offsets (needed only for file protocols)
 655  */
 656 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
 657                 const void *buf1, int count1)
 658 {
 659     BlockDriver *drv = bs->drv;
 660
 661     if (!drv)
 662         return -ENOMEDIUM;
 663     if (!drv->bdrv_pwrite)
 664         return bdrv_pwrite_em(bs, offset, buf1, count1);
 665     return drv->bdrv_pwrite(bs, offset, buf1, count1);
 666 }
 667
 668 /**
 669  * Truncate file to 'offset' bytes (needed only for file protocols)
 670  */
 671 int bdrv_truncate(BlockDriverState *bs, int64_t offset)
 672 {
 673     BlockDriver *drv = bs->drv;
 674     if (!drv)
 675         return -ENOMEDIUM;
 676     if (!drv->bdrv_truncate)
 677         return -ENOTSUP;
 678     return drv->bdrv_truncate(bs, offset);
 679 }
 680
 681 /**
 682  * Length of a file in bytes. Return < 0 if error or unknown.
 683  */
 684 int64_t bdrv_getlength(BlockDriverState *bs)
 685 {
 686     BlockDriver *drv = bs->drv;
 687     if (!drv)
 688         return -ENOMEDIUM;
 689     if (!drv->bdrv_getlength) {
 690         /* legacy mode */
 691         return bs->total_sectors * SECTOR_SIZE;
 692     }
 693     return drv->bdrv_getlength(bs);
 694 }
 695
 696 /* return 0 as number of sectors if no device present or error */
 697 void bdrv_get_geometry(BlockDriverState *bs, int64_t *nb_sectors_ptr)
 698 {
 699     int64_t length;
 700     length = bdrv_getlength(bs);
 701     if (length < 0)
 702         length = 0;
 703     else
 704         length = length >> SECTOR_BITS;
 705     *nb_sectors_ptr = length;
 706 }
 707
 708 /* force a given boot sector. */
 709 void bdrv_set_boot_sector(BlockDriverState *bs, const uint8_t *data, int size)
 710 {
 711     bs->boot_sector_enabled = 1;
 712     if (size > 512)
 713         size = 512;
 714     memcpy(bs->boot_sector_data, data, size);
 715     memset(bs->boot_sector_data + size, 0, 512 - size);
 716 }
 717
 718 void bdrv_set_geometry_hint(BlockDriverState *bs,
 719                             int cyls, int heads, int secs)
 720 {
 721     bs->cyls = cyls;
 722     bs->heads = heads;
 723     bs->secs = secs;
 724 }
 725
 726 void bdrv_set_type_hint(BlockDriverState *bs, int type)
 727 {
 728     bs->type = type;
 729     bs->removable = ((type == BDRV_TYPE_CDROM ||
 730                       type == BDRV_TYPE_FLOPPY));
 731 }
 732
 733 void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
 734 {
 735     bs->translation = translation;
 736 }
 737
 738 void bdrv_get_geometry_hint(BlockDriverState *bs,
 739                             int *pcyls, int *pheads, int *psecs)
 740 {
 741     *pcyls = bs->cyls;
 742     *pheads = bs->heads;
 743     *psecs = bs->secs;
 744 }
 745
 746 int bdrv_get_type_hint(BlockDriverState *bs)
 747 {
 748     return bs->type;
 749 }
 750
 751 int bdrv_get_translation_hint(BlockDriverState *bs)
 752 {
 753     return bs->translation;
 754 }
 755
 756 int bdrv_is_removable(BlockDriverState *bs)
 757 {
 758     return bs->removable;
 759 }
 760
 761 int bdrv_is_read_only(BlockDriverState *bs)
 762 {
 763     return bs->read_only;
 764 }
 765
 766 /* XXX: no longer used */
 767 void bdrv_set_change_cb(BlockDriverState *bs,
 768                         void (*change_cb)(void *opaque), void *opaque)
 769 {
 770     bs->change_cb = change_cb;
 771     bs->change_opaque = opaque;
 772 }
 773
 774 int bdrv_is_encrypted(BlockDriverState *bs)
 775 {
 776     if (bs->backing_hd && bs->backing_hd->encrypted)
 777         return 1;
 778     return bs->encrypted;
 779 }
 780
 781 int bdrv_set_key(BlockDriverState *bs, const char *key)
 782 {
 783     int ret;
 784     if (bs->backing_hd && bs->backing_hd->encrypted) {
 785         ret = bdrv_set_key(bs->backing_hd, key);
 786         if (ret < 0)
 787             return ret;
 788         if (!bs->encrypted)
 789             return 0;
 790     }
 791     if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
 792         return -1;
 793     return bs->drv->bdrv_set_key(bs, key);
 794 }
 795
 796 void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
 797 {
 798     if (!bs->drv) {
 799         buf[0] = '\0';
 800     } else {
 801         pstrcpy(buf, buf_size, bs->drv->format_name);
 802     }
 803 }
 804
 805 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
 806                          void *opaque)
 807 {
 808     BlockDriver *drv;
 809
 810     for (drv = first_drv; drv != NULL; drv = drv->next) {
 811         it(opaque, drv->format_name);
 812     }
 813 }
 814
 815 BlockDriverState *bdrv_find(const char *name)
 816 {
 817     BlockDriverState *bs;
 818
 819     for (bs = bdrv_first; bs != NULL; bs = bs->next) {
 820         if (!strcmp(name, bs->device_name))
 821             return bs;
 822     }
 823     return NULL;
 824 }
 825
 826 void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque)
 827 {
 828     BlockDriverState *bs;
 829
 830     for (bs = bdrv_first; bs != NULL; bs = bs->next) {
 831         it(opaque, bs->device_name);
 832     }
 833 }
 834
 835 const char *bdrv_get_device_name(BlockDriverState *bs)
 836 {
 837     return bs->device_name;
 838 }
 839
 840 void bdrv_flush(BlockDriverState *bs)
 841 {
 842     if (bs->drv->bdrv_flush)
 843         bs->drv->bdrv_flush(bs);
 844     if (bs->backing_hd)
 845         bdrv_flush(bs->backing_hd);
 846 }
 847
 848 void bdrv_info(void)
 849 {
 850     BlockDriverState *bs;
 851
 852     for (bs = bdrv_first; bs != NULL; bs = bs->next) {
 853         term_printf("%s:", bs->device_name);
 854         term_printf(" type=");
 855         switch(bs->type) {
 856         case BDRV_TYPE_HD:
 857             term_printf("hd");
 858             break;
 859         case BDRV_TYPE_CDROM:
 860             term_printf("cdrom");
 861             break;
 862         case BDRV_TYPE_FLOPPY:
 863             term_printf("floppy");
 864             break;
 865         }
 866         term_printf(" removable=%d", bs->removable);
 867         if (bs->removable) {
 868             term_printf(" locked=%d", bs->locked);
 869         }
 870         if (bs->drv) {
 871             term_printf(" file=%s", bs->filename);
 872             if (bs->backing_file[0] != '\0')
 873                 term_printf(" backing_file=%s", bs->backing_file);
 874             term_printf(" ro=%d", bs->read_only);
 875             term_printf(" drv=%s", bs->drv->format_name);
 876             if (bs->encrypted)
 877                 term_printf(" encrypted");
 878         } else {
 879             term_printf(" [not inserted]");
 880         }
 881         term_printf("\n");
 882     }
 883 }
 884
 885 void bdrv_get_backing_filename(BlockDriverState *bs,
 886                                char *filename, int filename_size)
 887 {
 888     if (!bs->backing_hd) {
 889         pstrcpy(filename, filename_size, "");
 890     } else {
 891         pstrcpy(filename, filename_size, bs->backing_file);
 892     }
 893 }
 894
 895 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
 896                           const uint8_t *buf, int nb_sectors)
 897 {
 898     BlockDriver *drv = bs->drv;
 899     if (!drv)
 900         return -ENOMEDIUM;
 901     if (!drv->bdrv_write_compressed)
 902         return -ENOTSUP;
 903     return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
 904 }
 905
 906 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 907 {
 908     BlockDriver *drv = bs->drv;
 909     if (!drv)
 910         return -ENOMEDIUM;
 911     if (!drv->bdrv_get_info)
 912         return -ENOTSUP;
 913     memset(bdi, 0, sizeof(*bdi));
 914     return drv->bdrv_get_info(bs, bdi);
 915 }
 916
 917 /**************************************************************/
 918 /* handling of snapshots */
 919
 920 int bdrv_snapshot_create(BlockDriverState *bs,
 921                          QEMUSnapshotInfo *sn_info)
 922 {
 923     BlockDriver *drv = bs->drv;
 924     if (!drv)
 925         return -ENOMEDIUM;
 926     if (!drv->bdrv_snapshot_create)
 927         return -ENOTSUP;
 928     return drv->bdrv_snapshot_create(bs, sn_info);
 929 }
 930
 931 int bdrv_snapshot_goto(BlockDriverState *bs,
 932                        const char *snapshot_id)
 933 {
 934     BlockDriver *drv = bs->drv;
 935     if (!drv)
 936         return -ENOMEDIUM;
 937     if (!drv->bdrv_snapshot_goto)
 938         return -ENOTSUP;
 939     return drv->bdrv_snapshot_goto(bs, snapshot_id);
 940 }
 941
 942 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
 943 {
 944     BlockDriver *drv = bs->drv;
 945     if (!drv)
 946         return -ENOMEDIUM;
 947     if (!drv->bdrv_snapshot_delete)
 948         return -ENOTSUP;
 949     return drv->bdrv_snapshot_delete(bs, snapshot_id);
 950 }
 951
 952 int bdrv_snapshot_list(BlockDriverState *bs,
 953                        QEMUSnapshotInfo **psn_info)
 954 {
 955     BlockDriver *drv = bs->drv;
 956     if (!drv)
 957         return -ENOMEDIUM;
 958     if (!drv->bdrv_snapshot_list)
 959         return -ENOTSUP;
 960     return drv->bdrv_snapshot_list(bs, psn_info);
 961 }
 962
 963 #define NB_SUFFIXES 4
 964
 965 char *get_human_readable_size(char *buf, int buf_size, int64_t size)
 966 {
 967     static const char suffixes[NB_SUFFIXES] = "KMGT";
 968     int64_t base;
 969     int i;
 970
 971     if (size <= 999) {
 972         snprintf(buf, buf_size, "%" PRId64, size);
 973     } else {
 974         base = 1024;
 975         for(i = 0; i < NB_SUFFIXES; i++) {
 976             if (size < (10 * base)) {
 977                 snprintf(buf, buf_size, "%0.1f%c",
 978                          (double)size / base,
 979                          suffixes[i]);
 980                 break;
 981             } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
 982                 snprintf(buf, buf_size, "%" PRId64 "%c",
 983                          ((size + (base >> 1)) / base),
 984                          suffixes[i]);
 985                 break;
 986             }
 987             base = base * 1024;
 988         }
 989     }
 990     return buf;
 991 }
 992
 993 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
 994 {
 995     char buf1[128], date_buf[128], clock_buf[128];
 996     struct tm tm;
 997     time_t ti;
 998     int64_t secs;
 999
1000     if (!sn) {
1001         snprintf(buf, buf_size,
1002                  "%-10s%-20s%7s%20s%15s",
1003                  "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1004     } else {
1005         ti = sn->date_sec;
1006 #ifndef _WIN32
1007         localtime_r(&ti, &tm);
1008 #endif
1009         strftime(date_buf, sizeof(date_buf),
1010                  "%Y-%m-%d %H:%M:%S", &tm);
1011         secs = sn->vm_clock_nsec / 1000000000;
1012         snprintf(clock_buf, sizeof(clock_buf),
1013                  "%02d:%02d:%02d.%03d",
1014                  (int)(secs / 3600),
1015                  (int)((secs / 60) % 60),
1016                  (int)(secs % 60),
1017                  (int)((sn->vm_clock_nsec / 1000000) % 1000));
1018         snprintf(buf, buf_size,
1019                  "%-10s%-20s%7s%20s%15s",
1020                  sn->id_str, sn->name,
1021                  get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1022                  date_buf,
1023                  clock_buf);
1024     }
1025     return buf;
1026 }
1027
1028
1029 /**************************************************************/
1030 /* async I/Os */
1031
1032 BlockDriverAIOCB *bdrv_aio_read(BlockDriverState *bs, int64_t sector_num,
1033                                 uint8_t *buf, int nb_sectors,
1034                                 BlockDriverCompletionFunc *cb, void *opaque)
1035 {
1036     BlockDriver *drv = bs->drv;
1037
1038     if (!drv)
1039         return NULL;
1040
1041     /* XXX: we assume that nb_sectors == 0 is suppored by the async read */
1042     if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
1043         memcpy(buf, bs->boot_sector_data, 512);
1044         sector_num++;
1045         nb_sectors--;
1046         buf += 512;
1047     }
1048
1049     return drv->bdrv_aio_read(bs, sector_num, buf, nb_sectors, cb, opaque);
1050 }
1051
1052 BlockDriverAIOCB *bdrv_aio_write(BlockDriverState *bs, int64_t sector_num,
1053                                  const uint8_t *buf, int nb_sectors,
1054                                  BlockDriverCompletionFunc *cb, void *opaque)
1055 {
1056     BlockDriver *drv = bs->drv;
1057
1058     if (!drv)
1059         return NULL;
1060     if (bs->read_only)
1061         return NULL;
1062     if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
1063         memcpy(bs->boot_sector_data, buf, 512);
1064     }
1065
1066     return drv->bdrv_aio_write(bs, sector_num, buf, nb_sectors, cb, opaque);
1067 }
1068
1069 void bdrv_aio_cancel(BlockDriverAIOCB *acb)
1070 {
1071     BlockDriver *drv = acb->bs->drv;
1072
1073     drv->bdrv_aio_cancel(acb);
1074 }
1075
1076
1077 /**************************************************************/
1078 /* async block device emulation */
1079
1080 #ifdef QEMU_TOOL
1081 static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
1082         int64_t sector_num, uint8_t *buf, int nb_sectors,
1083         BlockDriverCompletionFunc *cb, void *opaque)
1084 {
1085     int ret;
1086     ret = bdrv_read(bs, sector_num, buf, nb_sectors);
1087     cb(opaque, ret);
1088     return NULL;
1089 }
1090
1091 static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
1092         int64_t sector_num, const uint8_t *buf, int nb_sectors,
1093         BlockDriverCompletionFunc *cb, void *opaque)
1094 {
1095     int ret;
1096     ret = bdrv_write(bs, sector_num, buf, nb_sectors);
1097     cb(opaque, ret);
1098     return NULL;
1099 }
1100
1101 static void bdrv_aio_cancel_em(BlockDriverAIOCB *acb)
1102 {
1103 }
1104 #else
1105 static void bdrv_aio_bh_cb(void *opaque)
1106 {
1107     BlockDriverAIOCBSync *acb = opaque;
1108     acb->common.cb(acb->common.opaque, acb->ret);
1109     qemu_aio_release(acb);
1110 }
1111
1112 static BlockDriverAIOCB *bdrv_aio_read_em(BlockDriverState *bs,
1113         int64_t sector_num, uint8_t *buf, int nb_sectors,
1114         BlockDriverCompletionFunc *cb, void *opaque)
1115 {
1116     BlockDriverAIOCBSync *acb;
1117     int ret;
1118
1119     acb = qemu_aio_get(bs, cb, opaque);
1120     if (!acb->bh)
1121         acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1122     ret = bdrv_read(bs, sector_num, buf, nb_sectors);
1123     acb->ret = ret;
1124     qemu_bh_schedule(acb->bh);
1125     return &acb->common;
1126 }
1127
1128 static BlockDriverAIOCB *bdrv_aio_write_em(BlockDriverState *bs,
1129         int64_t sector_num, const uint8_t *buf, int nb_sectors,
1130         BlockDriverCompletionFunc *cb, void *opaque)
1131 {
1132     BlockDriverAIOCBSync *acb;
1133     int ret;
1134
1135     acb = qemu_aio_get(bs, cb, opaque);
1136     if (!acb->bh)
1137         acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
1138     ret = bdrv_write(bs, sector_num, buf, nb_sectors);
1139     acb->ret = ret;
1140     qemu_bh_schedule(acb->bh);
1141     return &acb->common;
1142 }
1143
1144 static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
1145 {
1146     BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb;
1147     qemu_bh_cancel(acb->bh);
1148     qemu_aio_release(acb);
1149 }
1150 #endif /* !QEMU_TOOL */
1151
1152 /**************************************************************/
1153 /* sync block device emulation */
1154
1155 static void bdrv_rw_em_cb(void *opaque, int ret)
1156 {
1157     *(int *)opaque = ret;
1158 }
1159
1160 #define NOT_DONE 0x7fffffff
1161
1162 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
1163                         uint8_t *buf, int nb_sectors)
1164 {
1165     int async_ret;
1166     BlockDriverAIOCB *acb;
1167
1168     async_ret = NOT_DONE;
1169     qemu_aio_wait_start();
1170     acb = bdrv_aio_read(bs, sector_num, buf, nb_sectors,
1171                         bdrv_rw_em_cb, &async_ret);
1172     if (acb == NULL) {
1173         qemu_aio_wait_end();
1174         return -1;
1175     }
1176     while (async_ret == NOT_DONE) {
1177         qemu_aio_wait();
1178     }
1179     qemu_aio_wait_end();
1180     return async_ret;
1181 }
1182
1183 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
1184                          const uint8_t *buf, int nb_sectors)
1185 {
1186     int async_ret;
1187     BlockDriverAIOCB *acb;
1188
1189     async_ret = NOT_DONE;
1190     qemu_aio_wait_start();
1191     acb = bdrv_aio_write(bs, sector_num, buf, nb_sectors,
1192                          bdrv_rw_em_cb, &async_ret);
1193     if (acb == NULL) {
1194         qemu_aio_wait_end();
1195         return -1;
1196     }
1197     while (async_ret == NOT_DONE) {
1198         qemu_aio_wait();
1199     }
1200     qemu_aio_wait_end();
1201     return async_ret;
1202 }
1203
1204 void bdrv_init(void)
1205 {
1206     bdrv_register(&bdrv_raw);
1207     bdrv_register(&bdrv_host_device);
1208 #ifndef _WIN32
1209     bdrv_register(&bdrv_cow);
1210 #endif
1211     bdrv_register(&bdrv_qcow);
1212     bdrv_register(&bdrv_vmdk);
1213     bdrv_register(&bdrv_cloop);
1214     bdrv_register(&bdrv_dmg);
1215     bdrv_register(&bdrv_bochs);
1216     bdrv_register(&bdrv_vpc);
1217     bdrv_register(&bdrv_vvfat);
1218     bdrv_register(&bdrv_qcow2);
1219 }
1220
1221 void *qemu_aio_get(BlockDriverState *bs, BlockDriverCompletionFunc *cb,
1222                    void *opaque)
1223 {
1224     BlockDriver *drv;
1225     BlockDriverAIOCB *acb;
1226
1227     drv = bs->drv;
1228     if (drv->free_aiocb) {
1229         acb = drv->free_aiocb;
1230         drv->free_aiocb = acb->next;
1231     } else {
1232         acb = qemu_mallocz(drv->aiocb_size);
1233         if (!acb)
1234             return NULL;
1235     }
1236     acb->bs = bs;
1237     acb->cb = cb;
1238     acb->opaque = opaque;
1239     return acb;
1240 }
1241
1242 void qemu_aio_release(void *p)
1243 {
1244     BlockDriverAIOCB *acb = p;
1245     BlockDriver *drv = acb->bs->drv;
1246     acb->next = drv->free_aiocb;
1247     drv->free_aiocb = acb;
1248 }
1249
1250 /**************************************************************/
1251 /* removable device support */
1252
1253 /**
1254  * Return TRUE if the media is present
1255  */
1256 int bdrv_is_inserted(BlockDriverState *bs)
1257 {
1258     BlockDriver *drv = bs->drv;
1259     int ret;
1260     if (!drv)
1261         return 0;
1262     if (!drv->bdrv_is_inserted)
1263         return 1;
1264     ret = drv->bdrv_is_inserted(bs);
1265     return ret;
1266 }
1267
1268 /**
1269  * Return TRUE if the media changed since the last call to this
1270  * function. It is currently only used for floppy disks
1271  */
1272 int bdrv_media_changed(BlockDriverState *bs)
1273 {
1274     BlockDriver *drv = bs->drv;
1275     int ret;
1276
1277     if (!drv || !drv->bdrv_media_changed)
1278         ret = -ENOTSUP;
1279     else
1280         ret = drv->bdrv_media_changed(bs);
1281     if (ret == -ENOTSUP)
1282         ret = bs->media_changed;
1283     bs->media_changed = 0;
1284     return ret;
1285 }
1286
1287 /**
1288  * If eject_flag is TRUE, eject the media. Otherwise, close the tray
1289  */
1290 void bdrv_eject(BlockDriverState *bs, int eject_flag)
1291 {
1292     BlockDriver *drv = bs->drv;
1293     int ret;
1294
1295     if (!drv || !drv->bdrv_eject) {
1296         ret = -ENOTSUP;
1297     } else {
1298         ret = drv->bdrv_eject(bs, eject_flag);
1299     }
1300     if (ret == -ENOTSUP) {
1301         if (eject_flag)
1302             bdrv_close(bs);
1303     }
1304 }
1305
1306 int bdrv_is_locked(BlockDriverState *bs)
1307 {
1308     return bs->locked;
1309 }
1310
1311 /**
1312  * Lock or unlock the media (if it is locked, the user won't be able
1313  * to eject it manually).
1314  */
1315 void bdrv_set_locked(BlockDriverState *bs, int locked)
1316 {
1317     BlockDriver *drv = bs->drv;
1318
1319     bs->locked = locked;
1320     if (drv && drv->bdrv_set_locked) {
1321         drv->bdrv_set_locked(bs, locked);
1322     }
1323 }