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 "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
 400             realpath(filename, backing_filename);
 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 }