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