1 /* 2 * QEMU System Emulator block driver 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #include "config-host.h" 25 #include "qemu-common.h" 26 #include "monitor.h" 27 #include "block_int.h" 28 #include "module.h" 29 #include "qemu-objects.h" 30 31 #ifdef CONFIG_BSD 32 #include <sys/types.h> 33 #include <sys/stat.h> 34 #include <sys/ioctl.h> 35 #include <sys/queue.h> 36 #ifndef __DragonFly__ 37 #include <sys/disk.h> 38 #endif 39 #endif 40 41 #ifdef _WIN32 42 #include <windows.h> 43 #endif 44 45 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 46 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 47 BlockDriverCompletionFunc *cb, void *opaque); 48 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 49 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 50 BlockDriverCompletionFunc *cb, void *opaque); 51 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs, 52 BlockDriverCompletionFunc *cb, void *opaque); 53 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num, 54 uint8_t *buf, int nb_sectors); 55 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num, 56 const uint8_t *buf, int nb_sectors); 57 58 BlockDriverState *bdrv_first; 59 60 static BlockDriver *first_drv; 61 62 /* If non-zero, use only whitelisted block drivers */ 63 static int use_bdrv_whitelist; 64 65 int path_is_absolute(const char *path) 66 { 67 const char *p; 68 #ifdef _WIN32 69 /* specific case for names like: "\\.\d:" */ 70 if (*path == '/' || *path == '\\') 71 return 1; 72 #endif 73 p = strchr(path, ':'); 74 if (p) 75 p++; 76 else 77 p = path; 78 #ifdef _WIN32 79 return (*p == '/' || *p == '\\'); 80 #else 81 return (*p == '/'); 82 #endif 83 } 84 85 /* if filename is absolute, just copy it to dest. Otherwise, build a 86 path to it by considering it is relative to base_path. URL are 87 supported. */ 88 void path_combine(char *dest, int dest_size, 89 const char *base_path, 90 const char *filename) 91 { 92 const char *p, *p1; 93 int len; 94 95 if (dest_size <= 0) 96 return; 97 if (path_is_absolute(filename)) { 98 pstrcpy(dest, dest_size, filename); 99 } else { 100 p = strchr(base_path, ':'); 101 if (p) 102 p++; 103 else 104 p = base_path; 105 p1 = strrchr(base_path, '/'); 106 #ifdef _WIN32 107 { 108 const char *p2; 109 p2 = strrchr(base_path, '\\'); 110 if (!p1 || p2 > p1) 111 p1 = p2; 112 } 113 #endif 114 if (p1) 115 p1++; 116 else 117 p1 = base_path; 118 if (p1 > p) 119 p = p1; 120 len = p - base_path; 121 if (len > dest_size - 1) 122 len = dest_size - 1; 123 memcpy(dest, base_path, len); 124 dest[len] = '\0'; 125 pstrcat(dest, dest_size, filename); 126 } 127 } 128 129 void bdrv_register(BlockDriver *bdrv) 130 { 131 if (!bdrv->bdrv_aio_readv) { 132 /* add AIO emulation layer */ 133 bdrv->bdrv_aio_readv = bdrv_aio_readv_em; 134 bdrv->bdrv_aio_writev = bdrv_aio_writev_em; 135 } else if (!bdrv->bdrv_read) { 136 /* add synchronous IO emulation layer */ 137 bdrv->bdrv_read = bdrv_read_em; 138 bdrv->bdrv_write = bdrv_write_em; 139 } 140 141 if (!bdrv->bdrv_aio_flush) 142 bdrv->bdrv_aio_flush = bdrv_aio_flush_em; 143 144 bdrv->next = first_drv; 145 first_drv = bdrv; 146 } 147 148 /* create a new block device (by default it is empty) */ 149 BlockDriverState *bdrv_new(const char *device_name) 150 { 151 BlockDriverState **pbs, *bs; 152 153 bs = qemu_mallocz(sizeof(BlockDriverState)); 154 pstrcpy(bs->device_name, sizeof(bs->device_name), device_name); 155 if (device_name[0] != '\0') { 156 /* insert at the end */ 157 pbs = &bdrv_first; 158 while (*pbs != NULL) 159 pbs = &(*pbs)->next; 160 *pbs = bs; 161 } 162 return bs; 163 } 164 165 BlockDriver *bdrv_find_format(const char *format_name) 166 { 167 BlockDriver *drv1; 168 for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { 169 if (!strcmp(drv1->format_name, format_name)) 170 return drv1; 171 } 172 return NULL; 173 } 174 175 static int bdrv_is_whitelisted(BlockDriver *drv) 176 { 177 static const char *whitelist[] = { 178 CONFIG_BDRV_WHITELIST 179 }; 180 const char **p; 181 182 if (!whitelist[0]) 183 return 1; /* no whitelist, anything goes */ 184 185 for (p = whitelist; *p; p++) { 186 if (!strcmp(drv->format_name, *p)) { 187 return 1; 188 } 189 } 190 return 0; 191 } 192 193 BlockDriver *bdrv_find_whitelisted_format(const char *format_name) 194 { 195 BlockDriver *drv = bdrv_find_format(format_name); 196 return drv && bdrv_is_whitelisted(drv) ? drv : NULL; 197 } 198 199 int bdrv_create(BlockDriver *drv, const char* filename, 200 QEMUOptionParameter *options) 201 { 202 if (!drv->bdrv_create) 203 return -ENOTSUP; 204 205 return drv->bdrv_create(filename, options); 206 } 207 208 #ifdef _WIN32 209 void get_tmp_filename(char *filename, int size) 210 { 211 char temp_dir[MAX_PATH]; 212 213 GetTempPath(MAX_PATH, temp_dir); 214 GetTempFileName(temp_dir, "qem", 0, filename); 215 } 216 #else 217 void get_tmp_filename(char *filename, int size) 218 { 219 int fd; 220 const char *tmpdir; 221 /* XXX: race condition possible */ 222 tmpdir = getenv("TMPDIR"); 223 if (!tmpdir) 224 tmpdir = "/tmp"; 225 snprintf(filename, size, "%s/vl.XXXXXX", tmpdir); 226 fd = mkstemp(filename); 227 close(fd); 228 } 229 #endif 230 231 #ifdef _WIN32 232 static int is_windows_drive_prefix(const char *filename) 233 { 234 return (((filename[0] >= 'a' && filename[0] <= 'z') || 235 (filename[0] >= 'A' && filename[0] <= 'Z')) && 236 filename[1] == ':'); 237 } 238 239 int is_windows_drive(const char *filename) 240 { 241 if (is_windows_drive_prefix(filename) && 242 filename[2] == '\0') 243 return 1; 244 if (strstart(filename, "\\\\.\\", NULL) || 245 strstart(filename, "//./", NULL)) 246 return 1; 247 return 0; 248 } 249 #endif 250 251 static BlockDriver *find_protocol(const char *filename) 252 { 253 BlockDriver *drv1; 254 char protocol[128]; 255 int len; 256 const char *p; 257 258 #ifdef _WIN32 259 if (is_windows_drive(filename) || 260 is_windows_drive_prefix(filename)) 261 return bdrv_find_format("raw"); 262 #endif 263 p = strchr(filename, ':'); 264 if (!p) 265 return bdrv_find_format("raw"); 266 len = p - filename; 267 if (len > sizeof(protocol) - 1) 268 len = sizeof(protocol) - 1; 269 memcpy(protocol, filename, len); 270 protocol[len] = '\0'; 271 for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { 272 if (drv1->protocol_name && 273 !strcmp(drv1->protocol_name, protocol)) 274 return drv1; 275 } 276 return NULL; 277 } 278 279 /* 280 * Detect host devices. By convention, /dev/cdrom[N] is always 281 * recognized as a host CDROM. 282 */ 283 static BlockDriver *find_hdev_driver(const char *filename) 284 { 285 int score_max = 0, score; 286 BlockDriver *drv = NULL, *d; 287 288 for (d = first_drv; d; d = d->next) { 289 if (d->bdrv_probe_device) { 290 score = d->bdrv_probe_device(filename); 291 if (score > score_max) { 292 score_max = score; 293 drv = d; 294 } 295 } 296 } 297 298 return drv; 299 } 300 301 static BlockDriver *find_image_format(const char *filename) 302 { 303 int ret, score, score_max; 304 BlockDriver *drv1, *drv; 305 uint8_t buf[2048]; 306 BlockDriverState *bs; 307 308 drv = find_protocol(filename); 309 /* no need to test disk image formats for vvfat */ 310 if (drv && strcmp(drv->format_name, "vvfat") == 0) 311 return drv; 312 313 ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY); 314 if (ret < 0) 315 return NULL; 316 ret = bdrv_pread(bs, 0, buf, sizeof(buf)); 317 bdrv_delete(bs); 318 if (ret < 0) { 319 return NULL; 320 } 321 322 score_max = 0; 323 for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { 324 if (drv1->bdrv_probe) { 325 score = drv1->bdrv_probe(buf, ret, filename); 326 if (score > score_max) { 327 score_max = score; 328 drv = drv1; 329 } 330 } 331 } 332 return drv; 333 } 334 335 int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags) 336 { 337 BlockDriverState *bs; 338 int ret; 339 340 bs = bdrv_new(""); 341 ret = bdrv_open2(bs, filename, flags | BDRV_O_FILE, NULL); 342 if (ret < 0) { 343 bdrv_delete(bs); 344 return ret; 345 } 346 bs->growable = 1; 347 *pbs = bs; 348 return 0; 349 } 350 351 int bdrv_open(BlockDriverState *bs, const char *filename, int flags) 352 { 353 return bdrv_open2(bs, filename, flags, NULL); 354 } 355 356 int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, 357 BlockDriver *drv) 358 { 359 int ret, open_flags, try_rw; 360 char tmp_filename[PATH_MAX]; 361 char backing_filename[PATH_MAX]; 362 363 bs->is_temporary = 0; 364 bs->encrypted = 0; 365 bs->valid_key = 0; 366 /* buffer_alignment defaulted to 512, drivers can change this value */ 367 bs->buffer_alignment = 512; 368 369 if (flags & BDRV_O_SNAPSHOT) { 370 BlockDriverState *bs1; 371 int64_t total_size; 372 int is_protocol = 0; 373 BlockDriver *bdrv_qcow2; 374 QEMUOptionParameter *options; 375 376 /* if snapshot, we create a temporary backing file and open it 377 instead of opening 'filename' directly */ 378 379 /* if there is a backing file, use it */ 380 bs1 = bdrv_new(""); 381 ret = bdrv_open2(bs1, filename, 0, drv); 382 if (ret < 0) { 383 bdrv_delete(bs1); 384 return ret; 385 } 386 total_size = bdrv_getlength(bs1) >> BDRV_SECTOR_BITS; 387 388 if (bs1->drv && bs1->drv->protocol_name) 389 is_protocol = 1; 390 391 bdrv_delete(bs1); 392 393 get_tmp_filename(tmp_filename, sizeof(tmp_filename)); 394 395 /* Real path is meaningless for protocols */ 396 if (is_protocol) 397 snprintf(backing_filename, sizeof(backing_filename), 398 "%s", filename); 399 else if (!realpath(filename, backing_filename)) 400 return -errno; 401 402 bdrv_qcow2 = bdrv_find_format("qcow2"); 403 options = parse_option_parameters("", bdrv_qcow2->create_options, NULL); 404 405 set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size * 512); 406 set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename); 407 if (drv) { 408 set_option_parameter(options, BLOCK_OPT_BACKING_FMT, 409 drv->format_name); 410 } 411 412 ret = bdrv_create(bdrv_qcow2, tmp_filename, options); 413 if (ret < 0) { 414 return ret; 415 } 416 417 filename = tmp_filename; 418 drv = bdrv_qcow2; 419 bs->is_temporary = 1; 420 } 421 422 pstrcpy(bs->filename, sizeof(bs->filename), filename); 423 if (flags & BDRV_O_FILE) { 424 drv = find_protocol(filename); 425 } else if (!drv) { 426 drv = find_hdev_driver(filename); 427 if (!drv) { 428 drv = find_image_format(filename); 429 } 430 } 431 if (!drv) { 432 ret = -ENOENT; 433 goto unlink_and_fail; 434 } 435 bs->drv = drv; 436 bs->opaque = qemu_mallocz(drv->instance_size); 437 438 /* 439 * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a 440 * write cache to the guest. We do need the fdatasync to flush 441 * out transactions for block allocations, and we maybe have a 442 * volatile write cache in our backing device to deal with. 443 */ 444 if (flags & (BDRV_O_CACHE_WB|BDRV_O_NOCACHE)) 445 bs->enable_write_cache = 1; 446 447 /* Note: for compatibility, we open disk image files as RDWR, and 448 RDONLY as fallback */ 449 try_rw = !bs->read_only || bs->is_temporary; 450 if (!(flags & BDRV_O_FILE)) 451 open_flags = (try_rw ? BDRV_O_RDWR : 0) | 452 (flags & (BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO)); 453 else 454 open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT); 455 if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) 456 ret = -ENOTSUP; 457 else 458 ret = drv->bdrv_open(bs, filename, open_flags); 459 if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) { 460 ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR); 461 bs->read_only = 1; 462 } 463 if (ret < 0) { 464 qemu_free(bs->opaque); 465 bs->opaque = NULL; 466 bs->drv = NULL; 467 unlink_and_fail: 468 if (bs->is_temporary) 469 unlink(filename); 470 return ret; 471 } 472 if (drv->bdrv_getlength) { 473 bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; 474 } 475 #ifndef _WIN32 476 if (bs->is_temporary) { 477 unlink(filename); 478 } 479 #endif 480 if ((flags & BDRV_O_NO_BACKING) == 0 && 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_file) { 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 } 2153