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, 0); 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; 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 } 431 432 if (!drv) { 433 ret = -ENOENT; 434 goto unlink_and_fail; 435 } 436 if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) { 437 ret = -ENOTSUP; 438 goto unlink_and_fail; 439 } 440 441 bs->drv = drv; 442 bs->opaque = qemu_mallocz(drv->instance_size); 443 444 /* 445 * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a 446 * write cache to the guest. We do need the fdatasync to flush 447 * out transactions for block allocations, and we maybe have a 448 * volatile write cache in our backing device to deal with. 449 */ 450 if (flags & (BDRV_O_CACHE_WB|BDRV_O_NOCACHE)) 451 bs->enable_write_cache = 1; 452 453 bs->read_only = (flags & BDRV_O_RDWR) == 0; 454 if (!(flags & BDRV_O_FILE)) { 455 open_flags = (flags & (BDRV_O_RDWR | BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO)); 456 if (bs->is_temporary) { /* snapshot should be writeable */ 457 open_flags |= BDRV_O_RDWR; 458 } 459 } else { 460 open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT); 461 } 462 463 ret = drv->bdrv_open(bs, filename, open_flags); 464 if (ret < 0) { 465 goto free_and_fail; 466 } 467 468 if (drv->bdrv_getlength) { 469 bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; 470 } 471 #ifndef _WIN32 472 if (bs->is_temporary) { 473 unlink(filename); 474 } 475 #endif 476 if ((flags & BDRV_O_NO_BACKING) == 0 && bs->backing_file[0] != '\0') { 477 /* if there is a backing file, use it */ 478 BlockDriver *back_drv = NULL; 479 bs->backing_hd = bdrv_new(""); 480 path_combine(backing_filename, sizeof(backing_filename), 481 filename, bs->backing_file); 482 if (bs->backing_format[0] != '\0') 483 back_drv = bdrv_find_format(bs->backing_format); 484 ret = bdrv_open2(bs->backing_hd, backing_filename, open_flags, 485 back_drv); 486 bs->backing_hd->read_only = (open_flags & BDRV_O_RDWR) == 0; 487 if (ret < 0) { 488 bdrv_close(bs); 489 return ret; 490 } 491 } 492 493 if (!bdrv_key_required(bs)) { 494 /* call the change callback */ 495 bs->media_changed = 1; 496 if (bs->change_cb) 497 bs->change_cb(bs->change_opaque); 498 } 499 return 0; 500 501 free_and_fail: 502 qemu_free(bs->opaque); 503 bs->opaque = NULL; 504 bs->drv = NULL; 505 unlink_and_fail: 506 if (bs->is_temporary) 507 unlink(filename); 508 return ret; 509 } 510 511 void bdrv_close(BlockDriverState *bs) 512 { 513 if (bs->drv) { 514 if (bs->backing_hd) 515 bdrv_delete(bs->backing_hd); 516 bs->drv->bdrv_close(bs); 517 qemu_free(bs->opaque); 518 #ifdef _WIN32 519 if (bs->is_temporary) { 520 unlink(bs->filename); 521 } 522 #endif 523 bs->opaque = NULL; 524 bs->drv = NULL; 525 526 /* call the change callback */ 527 bs->media_changed = 1; 528 if (bs->change_cb) 529 bs->change_cb(bs->change_opaque); 530 } 531 } 532 533 void bdrv_delete(BlockDriverState *bs) 534 { 535 BlockDriverState **pbs; 536 537 pbs = &bdrv_first; 538 while (*pbs != bs && *pbs != NULL) 539 pbs = &(*pbs)->next; 540 if (*pbs == bs) 541 *pbs = bs->next; 542 543 bdrv_close(bs); 544 qemu_free(bs); 545 } 546 547 /* 548 * Run consistency checks on an image 549 * 550 * Returns the number of errors or -errno when an internal error occurs 551 */ 552 int bdrv_check(BlockDriverState *bs) 553 { 554 if (bs->drv->bdrv_check == NULL) { 555 return -ENOTSUP; 556 } 557 558 return bs->drv->bdrv_check(bs); 559 } 560 561 /* commit COW file into the raw image */ 562 int bdrv_commit(BlockDriverState *bs) 563 { 564 BlockDriver *drv = bs->drv; 565 int64_t i, total_sectors; 566 int n, j; 567 int ret = 0; 568 unsigned char sector[512]; 569 570 if (!drv) 571 return -ENOMEDIUM; 572 573 if (bs->read_only) { 574 return -EACCES; 575 } 576 577 if (!bs->backing_hd) { 578 return -ENOTSUP; 579 } 580 581 total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; 582 for (i = 0; i < total_sectors;) { 583 if (drv->bdrv_is_allocated(bs, i, 65536, &n)) { 584 for(j = 0; j < n; j++) { 585 if (bdrv_read(bs, i, sector, 1) != 0) { 586 return -EIO; 587 } 588 589 if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) { 590 return -EIO; 591 } 592 i++; 593 } 594 } else { 595 i += n; 596 } 597 } 598 599 if (drv->bdrv_make_empty) { 600 ret = drv->bdrv_make_empty(bs); 601 bdrv_flush(bs); 602 } 603 604 /* 605 * Make sure all data we wrote to the backing device is actually 606 * stable on disk. 607 */ 608 if (bs->backing_hd) 609 bdrv_flush(bs->backing_hd); 610 return ret; 611 } 612 613 /* 614 * Return values: 615 * 0 - success 616 * -EINVAL - backing format specified, but no file 617 * -ENOSPC - can't update the backing file because no space is left in the 618 * image file header 619 * -ENOTSUP - format driver doesn't support changing the backing file 620 */ 621 int bdrv_change_backing_file(BlockDriverState *bs, 622 const char *backing_file, const char *backing_fmt) 623 { 624 BlockDriver *drv = bs->drv; 625 626 if (drv->bdrv_change_backing_file != NULL) { 627 return drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); 628 } else { 629 return -ENOTSUP; 630 } 631 } 632 633 static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 634 size_t size) 635 { 636 int64_t len; 637 638 if (!bdrv_is_inserted(bs)) 639 return -ENOMEDIUM; 640 641 if (bs->growable) 642 return 0; 643 644 len = bdrv_getlength(bs); 645 646 if (offset < 0) 647 return -EIO; 648 649 if ((offset > len) || (len - offset < size)) 650 return -EIO; 651 652 return 0; 653 } 654 655 static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, 656 int nb_sectors) 657 { 658 return bdrv_check_byte_request(bs, sector_num * 512, nb_sectors * 512); 659 } 660 661 /* return < 0 if error. See bdrv_write() for the return codes */ 662 int bdrv_read(BlockDriverState *bs, int64_t sector_num, 663 uint8_t *buf, int nb_sectors) 664 { 665 BlockDriver *drv = bs->drv; 666 667 if (!drv) 668 return -ENOMEDIUM; 669 if (bdrv_check_request(bs, sector_num, nb_sectors)) 670 return -EIO; 671 672 return drv->bdrv_read(bs, sector_num, buf, nb_sectors); 673 } 674 675 static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num, 676 int nb_sectors, int dirty) 677 { 678 int64_t start, end; 679 unsigned long val, idx, bit; 680 681 start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK; 682 end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK; 683 684 for (; start <= end; start++) { 685 idx = start / (sizeof(unsigned long) * 8); 686 bit = start % (sizeof(unsigned long) * 8); 687 val = bs->dirty_bitmap[idx]; 688 if (dirty) { 689 val |= 1 << bit; 690 } else { 691 val &= ~(1 << bit); 692 } 693 bs->dirty_bitmap[idx] = val; 694 } 695 } 696 697 /* Return < 0 if error. Important errors are: 698 -EIO generic I/O error (may happen for all errors) 699 -ENOMEDIUM No media inserted. 700 -EINVAL Invalid sector number or nb_sectors 701 -EACCES Trying to write a read-only device 702 */ 703 int bdrv_write(BlockDriverState *bs, int64_t sector_num, 704 const uint8_t *buf, int nb_sectors) 705 { 706 BlockDriver *drv = bs->drv; 707 if (!bs->drv) 708 return -ENOMEDIUM; 709 if (bs->read_only) 710 return -EACCES; 711 if (bdrv_check_request(bs, sector_num, nb_sectors)) 712 return -EIO; 713 714 if (bs->dirty_bitmap) { 715 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 716 } 717 718 return drv->bdrv_write(bs, sector_num, buf, nb_sectors); 719 } 720 721 int bdrv_pread(BlockDriverState *bs, int64_t offset, 722 void *buf, int count1) 723 { 724 uint8_t tmp_buf[BDRV_SECTOR_SIZE]; 725 int len, nb_sectors, count; 726 int64_t sector_num; 727 int ret; 728 729 count = count1; 730 /* first read to align to sector start */ 731 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); 732 if (len > count) 733 len = count; 734 sector_num = offset >> BDRV_SECTOR_BITS; 735 if (len > 0) { 736 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 737 return ret; 738 memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len); 739 count -= len; 740 if (count == 0) 741 return count1; 742 sector_num++; 743 buf += len; 744 } 745 746 /* read the sectors "in place" */ 747 nb_sectors = count >> BDRV_SECTOR_BITS; 748 if (nb_sectors > 0) { 749 if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0) 750 return ret; 751 sector_num += nb_sectors; 752 len = nb_sectors << BDRV_SECTOR_BITS; 753 buf += len; 754 count -= len; 755 } 756 757 /* add data from the last sector */ 758 if (count > 0) { 759 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 760 return ret; 761 memcpy(buf, tmp_buf, count); 762 } 763 return count1; 764 } 765 766 int bdrv_pwrite(BlockDriverState *bs, int64_t offset, 767 const void *buf, int count1) 768 { 769 uint8_t tmp_buf[BDRV_SECTOR_SIZE]; 770 int len, nb_sectors, count; 771 int64_t sector_num; 772 int ret; 773 774 count = count1; 775 /* first write to align to sector start */ 776 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); 777 if (len > count) 778 len = count; 779 sector_num = offset >> BDRV_SECTOR_BITS; 780 if (len > 0) { 781 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 782 return ret; 783 memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len); 784 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0) 785 return ret; 786 count -= len; 787 if (count == 0) 788 return count1; 789 sector_num++; 790 buf += len; 791 } 792 793 /* write the sectors "in place" */ 794 nb_sectors = count >> BDRV_SECTOR_BITS; 795 if (nb_sectors > 0) { 796 if ((ret = bdrv_write(bs, sector_num, buf, nb_sectors)) < 0) 797 return ret; 798 sector_num += nb_sectors; 799 len = nb_sectors << BDRV_SECTOR_BITS; 800 buf += len; 801 count -= len; 802 } 803 804 /* add data from the last sector */ 805 if (count > 0) { 806 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 807 return ret; 808 memcpy(tmp_buf, buf, count); 809 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0) 810 return ret; 811 } 812 return count1; 813 } 814 815 /** 816 * Truncate file to 'offset' bytes (needed only for file protocols) 817 */ 818 int bdrv_truncate(BlockDriverState *bs, int64_t offset) 819 { 820 BlockDriver *drv = bs->drv; 821 if (!drv) 822 return -ENOMEDIUM; 823 if (!drv->bdrv_truncate) 824 return -ENOTSUP; 825 if (bs->read_only) 826 return -EACCES; 827 return drv->bdrv_truncate(bs, offset); 828 } 829 830 /** 831 * Length of a file in bytes. Return < 0 if error or unknown. 832 */ 833 int64_t bdrv_getlength(BlockDriverState *bs) 834 { 835 BlockDriver *drv = bs->drv; 836 if (!drv) 837 return -ENOMEDIUM; 838 if (!drv->bdrv_getlength) { 839 /* legacy mode */ 840 return bs->total_sectors * BDRV_SECTOR_SIZE; 841 } 842 return drv->bdrv_getlength(bs); 843 } 844 845 /* return 0 as number of sectors if no device present or error */ 846 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr) 847 { 848 int64_t length; 849 length = bdrv_getlength(bs); 850 if (length < 0) 851 length = 0; 852 else 853 length = length >> BDRV_SECTOR_BITS; 854 *nb_sectors_ptr = length; 855 } 856 857 struct partition { 858 uint8_t boot_ind; /* 0x80 - active */ 859 uint8_t head; /* starting head */ 860 uint8_t sector; /* starting sector */ 861 uint8_t cyl; /* starting cylinder */ 862 uint8_t sys_ind; /* What partition type */ 863 uint8_t end_head; /* end head */ 864 uint8_t end_sector; /* end sector */ 865 uint8_t end_cyl; /* end cylinder */ 866 uint32_t start_sect; /* starting sector counting from 0 */ 867 uint32_t nr_sects; /* nr of sectors in partition */ 868 } __attribute__((packed)); 869 870 /* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */ 871 static int guess_disk_lchs(BlockDriverState *bs, 872 int *pcylinders, int *pheads, int *psectors) 873 { 874 uint8_t buf[512]; 875 int ret, i, heads, sectors, cylinders; 876 struct partition *p; 877 uint32_t nr_sects; 878 uint64_t nb_sectors; 879 880 bdrv_get_geometry(bs, &nb_sectors); 881 882 ret = bdrv_read(bs, 0, buf, 1); 883 if (ret < 0) 884 return -1; 885 /* test msdos magic */ 886 if (buf[510] != 0x55 || buf[511] != 0xaa) 887 return -1; 888 for(i = 0; i < 4; i++) { 889 p = ((struct partition *)(buf + 0x1be)) + i; 890 nr_sects = le32_to_cpu(p->nr_sects); 891 if (nr_sects && p->end_head) { 892 /* We make the assumption that the partition terminates on 893 a cylinder boundary */ 894 heads = p->end_head + 1; 895 sectors = p->end_sector & 63; 896 if (sectors == 0) 897 continue; 898 cylinders = nb_sectors / (heads * sectors); 899 if (cylinders < 1 || cylinders > 16383) 900 continue; 901 *pheads = heads; 902 *psectors = sectors; 903 *pcylinders = cylinders; 904 #if 0 905 printf("guessed geometry: LCHS=%d %d %d\n", 906 cylinders, heads, sectors); 907 #endif 908 return 0; 909 } 910 } 911 return -1; 912 } 913 914 void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs) 915 { 916 int translation, lba_detected = 0; 917 int cylinders, heads, secs; 918 uint64_t nb_sectors; 919 920 /* if a geometry hint is available, use it */ 921 bdrv_get_geometry(bs, &nb_sectors); 922 bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs); 923 translation = bdrv_get_translation_hint(bs); 924 if (cylinders != 0) { 925 *pcyls = cylinders; 926 *pheads = heads; 927 *psecs = secs; 928 } else { 929 if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) { 930 if (heads > 16) { 931 /* if heads > 16, it means that a BIOS LBA 932 translation was active, so the default 933 hardware geometry is OK */ 934 lba_detected = 1; 935 goto default_geometry; 936 } else { 937 *pcyls = cylinders; 938 *pheads = heads; 939 *psecs = secs; 940 /* disable any translation to be in sync with 941 the logical geometry */ 942 if (translation == BIOS_ATA_TRANSLATION_AUTO) { 943 bdrv_set_translation_hint(bs, 944 BIOS_ATA_TRANSLATION_NONE); 945 } 946 } 947 } else { 948 default_geometry: 949 /* if no geometry, use a standard physical disk geometry */ 950 cylinders = nb_sectors / (16 * 63); 951 952 if (cylinders > 16383) 953 cylinders = 16383; 954 else if (cylinders < 2) 955 cylinders = 2; 956 *pcyls = cylinders; 957 *pheads = 16; 958 *psecs = 63; 959 if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) { 960 if ((*pcyls * *pheads) <= 131072) { 961 bdrv_set_translation_hint(bs, 962 BIOS_ATA_TRANSLATION_LARGE); 963 } else { 964 bdrv_set_translation_hint(bs, 965 BIOS_ATA_TRANSLATION_LBA); 966 } 967 } 968 } 969 bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs); 970 } 971 } 972 973 void bdrv_set_geometry_hint(BlockDriverState *bs, 974 int cyls, int heads, int secs) 975 { 976 bs->cyls = cyls; 977 bs->heads = heads; 978 bs->secs = secs; 979 } 980 981 void bdrv_set_type_hint(BlockDriverState *bs, int type) 982 { 983 bs->type = type; 984 bs->removable = ((type == BDRV_TYPE_CDROM || 985 type == BDRV_TYPE_FLOPPY)); 986 } 987 988 void bdrv_set_translation_hint(BlockDriverState *bs, int translation) 989 { 990 bs->translation = translation; 991 } 992 993 void bdrv_get_geometry_hint(BlockDriverState *bs, 994 int *pcyls, int *pheads, int *psecs) 995 { 996 *pcyls = bs->cyls; 997 *pheads = bs->heads; 998 *psecs = bs->secs; 999 } 1000 1001 int bdrv_get_type_hint(BlockDriverState *bs) 1002 { 1003 return bs->type; 1004 } 1005 1006 int bdrv_get_translation_hint(BlockDriverState *bs) 1007 { 1008 return bs->translation; 1009 } 1010 1011 int bdrv_is_removable(BlockDriverState *bs) 1012 { 1013 return bs->removable; 1014 } 1015 1016 int bdrv_is_read_only(BlockDriverState *bs) 1017 { 1018 return bs->read_only; 1019 } 1020 1021 int bdrv_is_sg(BlockDriverState *bs) 1022 { 1023 return bs->sg; 1024 } 1025 1026 int bdrv_enable_write_cache(BlockDriverState *bs) 1027 { 1028 return bs->enable_write_cache; 1029 } 1030 1031 /* XXX: no longer used */ 1032 void bdrv_set_change_cb(BlockDriverState *bs, 1033 void (*change_cb)(void *opaque), void *opaque) 1034 { 1035 bs->change_cb = change_cb; 1036 bs->change_opaque = opaque; 1037 } 1038 1039 int bdrv_is_encrypted(BlockDriverState *bs) 1040 { 1041 if (bs->backing_hd && bs->backing_hd->encrypted) 1042 return 1; 1043 return bs->encrypted; 1044 } 1045 1046 int bdrv_key_required(BlockDriverState *bs) 1047 { 1048 BlockDriverState *backing_hd = bs->backing_hd; 1049 1050 if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key) 1051 return 1; 1052 return (bs->encrypted && !bs->valid_key); 1053 } 1054 1055 int bdrv_set_key(BlockDriverState *bs, const char *key) 1056 { 1057 int ret; 1058 if (bs->backing_hd && bs->backing_hd->encrypted) { 1059 ret = bdrv_set_key(bs->backing_hd, key); 1060 if (ret < 0) 1061 return ret; 1062 if (!bs->encrypted) 1063 return 0; 1064 } 1065 if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key) 1066 return -1; 1067 ret = bs->drv->bdrv_set_key(bs, key); 1068 if (ret < 0) { 1069 bs->valid_key = 0; 1070 } else if (!bs->valid_key) { 1071 bs->valid_key = 1; 1072 /* call the change callback now, we skipped it on open */ 1073 bs->media_changed = 1; 1074 if (bs->change_cb) 1075 bs->change_cb(bs->change_opaque); 1076 } 1077 return ret; 1078 } 1079 1080 void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size) 1081 { 1082 if (!bs->drv) { 1083 buf[0] = '\0'; 1084 } else { 1085 pstrcpy(buf, buf_size, bs->drv->format_name); 1086 } 1087 } 1088 1089 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 1090 void *opaque) 1091 { 1092 BlockDriver *drv; 1093 1094 for (drv = first_drv; drv != NULL; drv = drv->next) { 1095 it(opaque, drv->format_name); 1096 } 1097 } 1098 1099 BlockDriverState *bdrv_find(const char *name) 1100 { 1101 BlockDriverState *bs; 1102 1103 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1104 if (!strcmp(name, bs->device_name)) 1105 return bs; 1106 } 1107 return NULL; 1108 } 1109 1110 void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque) 1111 { 1112 BlockDriverState *bs; 1113 1114 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1115 it(opaque, bs); 1116 } 1117 } 1118 1119 const char *bdrv_get_device_name(BlockDriverState *bs) 1120 { 1121 return bs->device_name; 1122 } 1123 1124 void bdrv_flush(BlockDriverState *bs) 1125 { 1126 if (bs->drv && bs->drv->bdrv_flush) 1127 bs->drv->bdrv_flush(bs); 1128 } 1129 1130 void bdrv_flush_all(void) 1131 { 1132 BlockDriverState *bs; 1133 1134 for (bs = bdrv_first; bs != NULL; bs = bs->next) 1135 if (bs->drv && !bdrv_is_read_only(bs) && 1136 (!bdrv_is_removable(bs) || bdrv_is_inserted(bs))) 1137 bdrv_flush(bs); 1138 } 1139 1140 /* 1141 * Returns true iff the specified sector is present in the disk image. Drivers 1142 * not implementing the functionality are assumed to not support backing files, 1143 * hence all their sectors are reported as allocated. 1144 * 1145 * 'pnum' is set to the number of sectors (including and immediately following 1146 * the specified sector) that are known to be in the same 1147 * allocated/unallocated state. 1148 * 1149 * 'nb_sectors' is the max value 'pnum' should be set to. 1150 */ 1151 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, 1152 int *pnum) 1153 { 1154 int64_t n; 1155 if (!bs->drv->bdrv_is_allocated) { 1156 if (sector_num >= bs->total_sectors) { 1157 *pnum = 0; 1158 return 0; 1159 } 1160 n = bs->total_sectors - sector_num; 1161 *pnum = (n < nb_sectors) ? (n) : (nb_sectors); 1162 return 1; 1163 } 1164 return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum); 1165 } 1166 1167 static void bdrv_print_dict(QObject *obj, void *opaque) 1168 { 1169 QDict *bs_dict; 1170 Monitor *mon = opaque; 1171 1172 bs_dict = qobject_to_qdict(obj); 1173 1174 monitor_printf(mon, "%s: type=%s removable=%d", 1175 qdict_get_str(bs_dict, "device"), 1176 qdict_get_str(bs_dict, "type"), 1177 qdict_get_bool(bs_dict, "removable")); 1178 1179 if (qdict_get_bool(bs_dict, "removable")) { 1180 monitor_printf(mon, " locked=%d", qdict_get_bool(bs_dict, "locked")); 1181 } 1182 1183 if (qdict_haskey(bs_dict, "inserted")) { 1184 QDict *qdict = qobject_to_qdict(qdict_get(bs_dict, "inserted")); 1185 1186 monitor_printf(mon, " file="); 1187 monitor_print_filename(mon, qdict_get_str(qdict, "file")); 1188 if (qdict_haskey(qdict, "backing_file")) { 1189 monitor_printf(mon, " backing_file="); 1190 monitor_print_filename(mon, qdict_get_str(qdict, "backing_file")); 1191 } 1192 monitor_printf(mon, " ro=%d drv=%s encrypted=%d", 1193 qdict_get_bool(qdict, "ro"), 1194 qdict_get_str(qdict, "drv"), 1195 qdict_get_bool(qdict, "encrypted")); 1196 } else { 1197 monitor_printf(mon, " [not inserted]"); 1198 } 1199 1200 monitor_printf(mon, "\n"); 1201 } 1202 1203 void bdrv_info_print(Monitor *mon, const QObject *data) 1204 { 1205 qlist_iter(qobject_to_qlist(data), bdrv_print_dict, mon); 1206 } 1207 1208 /** 1209 * bdrv_info(): Block devices information 1210 * 1211 * Each block device information is stored in a QDict and the 1212 * returned QObject is a QList of all devices. 1213 * 1214 * The QDict contains the following: 1215 * 1216 * - "device": device name 1217 * - "type": device type 1218 * - "removable": true if the device is removable, false otherwise 1219 * - "locked": true if the device is locked, false otherwise 1220 * - "inserted": only present if the device is inserted, it is a QDict 1221 * containing the following: 1222 * - "file": device file name 1223 * - "ro": true if read-only, false otherwise 1224 * - "drv": driver format name 1225 * - "backing_file": backing file name if one is used 1226 * - "encrypted": true if encrypted, false otherwise 1227 * 1228 * Example: 1229 * 1230 * [ { "device": "ide0-hd0", "type": "hd", "removable": false, "locked": false, 1231 * "inserted": { "file": "/tmp/foobar", "ro": false, "drv": "qcow2" } }, 1232 * { "device": "floppy0", "type": "floppy", "removable": true, 1233 * "locked": false } ] 1234 */ 1235 void bdrv_info(Monitor *mon, QObject **ret_data) 1236 { 1237 QList *bs_list; 1238 BlockDriverState *bs; 1239 1240 bs_list = qlist_new(); 1241 1242 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1243 QObject *bs_obj; 1244 const char *type = "unknown"; 1245 1246 switch(bs->type) { 1247 case BDRV_TYPE_HD: 1248 type = "hd"; 1249 break; 1250 case BDRV_TYPE_CDROM: 1251 type = "cdrom"; 1252 break; 1253 case BDRV_TYPE_FLOPPY: 1254 type = "floppy"; 1255 break; 1256 } 1257 1258 bs_obj = qobject_from_jsonf("{ 'device': %s, 'type': %s, " 1259 "'removable': %i, 'locked': %i }", 1260 bs->device_name, type, bs->removable, 1261 bs->locked); 1262 assert(bs_obj != NULL); 1263 1264 if (bs->drv) { 1265 QObject *obj; 1266 QDict *bs_dict = qobject_to_qdict(bs_obj); 1267 1268 obj = qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, " 1269 "'encrypted': %i }", 1270 bs->filename, bs->read_only, 1271 bs->drv->format_name, 1272 bdrv_is_encrypted(bs)); 1273 assert(obj != NULL); 1274 if (bs->backing_file[0] != '\0') { 1275 QDict *qdict = qobject_to_qdict(obj); 1276 qdict_put(qdict, "backing_file", 1277 qstring_from_str(bs->backing_file)); 1278 } 1279 1280 qdict_put_obj(bs_dict, "inserted", obj); 1281 } 1282 qlist_append_obj(bs_list, bs_obj); 1283 } 1284 1285 *ret_data = QOBJECT(bs_list); 1286 } 1287 1288 static void bdrv_stats_iter(QObject *data, void *opaque) 1289 { 1290 QDict *qdict; 1291 Monitor *mon = opaque; 1292 1293 qdict = qobject_to_qdict(data); 1294 monitor_printf(mon, "%s:", qdict_get_str(qdict, "device")); 1295 1296 qdict = qobject_to_qdict(qdict_get(qdict, "stats")); 1297 monitor_printf(mon, " rd_bytes=%" PRId64 1298 " wr_bytes=%" PRId64 1299 " rd_operations=%" PRId64 1300 " wr_operations=%" PRId64 1301 "\n", 1302 qdict_get_int(qdict, "rd_bytes"), 1303 qdict_get_int(qdict, "wr_bytes"), 1304 qdict_get_int(qdict, "rd_operations"), 1305 qdict_get_int(qdict, "wr_operations")); 1306 } 1307 1308 void bdrv_stats_print(Monitor *mon, const QObject *data) 1309 { 1310 qlist_iter(qobject_to_qlist(data), bdrv_stats_iter, mon); 1311 } 1312 1313 /** 1314 * bdrv_info_stats(): show block device statistics 1315 * 1316 * Each device statistic information is stored in a QDict and 1317 * the returned QObject is a QList of all devices. 1318 * 1319 * The QDict contains the following: 1320 * 1321 * - "device": device name 1322 * - "stats": A QDict with the statistics information, it contains: 1323 * - "rd_bytes": bytes read 1324 * - "wr_bytes": bytes written 1325 * - "rd_operations": read operations 1326 * - "wr_operations": write operations 1327 * 1328 * Example: 1329 * 1330 * [ { "device": "ide0-hd0", 1331 * "stats": { "rd_bytes": 512, 1332 * "wr_bytes": 0, 1333 * "rd_operations": 1, 1334 * "wr_operations": 0 } }, 1335 * { "device": "ide1-cd0", 1336 * "stats": { "rd_bytes": 0, 1337 * "wr_bytes": 0, 1338 * "rd_operations": 0, 1339 * "wr_operations": 0 } } ] 1340 */ 1341 void bdrv_info_stats(Monitor *mon, QObject **ret_data) 1342 { 1343 QObject *obj; 1344 QList *devices; 1345 BlockDriverState *bs; 1346 1347 devices = qlist_new(); 1348 1349 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1350 obj = qobject_from_jsonf("{ 'device': %s, 'stats': {" 1351 "'rd_bytes': %" PRId64 "," 1352 "'wr_bytes': %" PRId64 "," 1353 "'rd_operations': %" PRId64 "," 1354 "'wr_operations': %" PRId64 1355 "} }", 1356 bs->device_name, 1357 bs->rd_bytes, bs->wr_bytes, 1358 bs->rd_ops, bs->wr_ops); 1359 assert(obj != NULL); 1360 qlist_append_obj(devices, obj); 1361 } 1362 1363 *ret_data = QOBJECT(devices); 1364 } 1365 1366 const char *bdrv_get_encrypted_filename(BlockDriverState *bs) 1367 { 1368 if (bs->backing_hd && bs->backing_hd->encrypted) 1369 return bs->backing_file; 1370 else if (bs->encrypted) 1371 return bs->filename; 1372 else 1373 return NULL; 1374 } 1375 1376 void bdrv_get_backing_filename(BlockDriverState *bs, 1377 char *filename, int filename_size) 1378 { 1379 if (!bs->backing_file) { 1380 pstrcpy(filename, filename_size, ""); 1381 } else { 1382 pstrcpy(filename, filename_size, bs->backing_file); 1383 } 1384 } 1385 1386 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num, 1387 const uint8_t *buf, int nb_sectors) 1388 { 1389 BlockDriver *drv = bs->drv; 1390 if (!drv) 1391 return -ENOMEDIUM; 1392 if (!drv->bdrv_write_compressed) 1393 return -ENOTSUP; 1394 if (bdrv_check_request(bs, sector_num, nb_sectors)) 1395 return -EIO; 1396 1397 if (bs->dirty_bitmap) { 1398 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 1399 } 1400 1401 return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors); 1402 } 1403 1404 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1405 { 1406 BlockDriver *drv = bs->drv; 1407 if (!drv) 1408 return -ENOMEDIUM; 1409 if (!drv->bdrv_get_info) 1410 return -ENOTSUP; 1411 memset(bdi, 0, sizeof(*bdi)); 1412 return drv->bdrv_get_info(bs, bdi); 1413 } 1414 1415 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 1416 int64_t pos, int size) 1417 { 1418 BlockDriver *drv = bs->drv; 1419 if (!drv) 1420 return -ENOMEDIUM; 1421 if (!drv->bdrv_save_vmstate) 1422 return -ENOTSUP; 1423 return drv->bdrv_save_vmstate(bs, buf, pos, size); 1424 } 1425 1426 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 1427 int64_t pos, int size) 1428 { 1429 BlockDriver *drv = bs->drv; 1430 if (!drv) 1431 return -ENOMEDIUM; 1432 if (!drv->bdrv_load_vmstate) 1433 return -ENOTSUP; 1434 return drv->bdrv_load_vmstate(bs, buf, pos, size); 1435 } 1436 1437 /**************************************************************/ 1438 /* handling of snapshots */ 1439 1440 int bdrv_snapshot_create(BlockDriverState *bs, 1441 QEMUSnapshotInfo *sn_info) 1442 { 1443 BlockDriver *drv = bs->drv; 1444 if (!drv) 1445 return -ENOMEDIUM; 1446 if (!drv->bdrv_snapshot_create) 1447 return -ENOTSUP; 1448 return drv->bdrv_snapshot_create(bs, sn_info); 1449 } 1450 1451 int bdrv_snapshot_goto(BlockDriverState *bs, 1452 const char *snapshot_id) 1453 { 1454 BlockDriver *drv = bs->drv; 1455 if (!drv) 1456 return -ENOMEDIUM; 1457 if (!drv->bdrv_snapshot_goto) 1458 return -ENOTSUP; 1459 return drv->bdrv_snapshot_goto(bs, snapshot_id); 1460 } 1461 1462 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) 1463 { 1464 BlockDriver *drv = bs->drv; 1465 if (!drv) 1466 return -ENOMEDIUM; 1467 if (!drv->bdrv_snapshot_delete) 1468 return -ENOTSUP; 1469 return drv->bdrv_snapshot_delete(bs, snapshot_id); 1470 } 1471 1472 int bdrv_snapshot_list(BlockDriverState *bs, 1473 QEMUSnapshotInfo **psn_info) 1474 { 1475 BlockDriver *drv = bs->drv; 1476 if (!drv) 1477 return -ENOMEDIUM; 1478 if (!drv->bdrv_snapshot_list) 1479 return -ENOTSUP; 1480 return drv->bdrv_snapshot_list(bs, psn_info); 1481 } 1482 1483 #define NB_SUFFIXES 4 1484 1485 char *get_human_readable_size(char *buf, int buf_size, int64_t size) 1486 { 1487 static const char suffixes[NB_SUFFIXES] = "KMGT"; 1488 int64_t base; 1489 int i; 1490 1491 if (size <= 999) { 1492 snprintf(buf, buf_size, "%" PRId64, size); 1493 } else { 1494 base = 1024; 1495 for(i = 0; i < NB_SUFFIXES; i++) { 1496 if (size < (10 * base)) { 1497 snprintf(buf, buf_size, "%0.1f%c", 1498 (double)size / base, 1499 suffixes[i]); 1500 break; 1501 } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) { 1502 snprintf(buf, buf_size, "%" PRId64 "%c", 1503 ((size + (base >> 1)) / base), 1504 suffixes[i]); 1505 break; 1506 } 1507 base = base * 1024; 1508 } 1509 } 1510 return buf; 1511 } 1512 1513 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn) 1514 { 1515 char buf1[128], date_buf[128], clock_buf[128]; 1516 #ifdef _WIN32 1517 struct tm *ptm; 1518 #else 1519 struct tm tm; 1520 #endif 1521 time_t ti; 1522 int64_t secs; 1523 1524 if (!sn) { 1525 snprintf(buf, buf_size, 1526 "%-10s%-20s%7s%20s%15s", 1527 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK"); 1528 } else { 1529 ti = sn->date_sec; 1530 #ifdef _WIN32 1531 ptm = localtime(&ti); 1532 strftime(date_buf, sizeof(date_buf), 1533 "%Y-%m-%d %H:%M:%S", ptm); 1534 #else 1535 localtime_r(&ti, &tm); 1536 strftime(date_buf, sizeof(date_buf), 1537 "%Y-%m-%d %H:%M:%S", &tm); 1538 #endif 1539 secs = sn->vm_clock_nsec / 1000000000; 1540 snprintf(clock_buf, sizeof(clock_buf), 1541 "%02d:%02d:%02d.%03d", 1542 (int)(secs / 3600), 1543 (int)((secs / 60) % 60), 1544 (int)(secs % 60), 1545 (int)((sn->vm_clock_nsec / 1000000) % 1000)); 1546 snprintf(buf, buf_size, 1547 "%-10s%-20s%7s%20s%15s", 1548 sn->id_str, sn->name, 1549 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size), 1550 date_buf, 1551 clock_buf); 1552 } 1553 return buf; 1554 } 1555 1556 1557 /**************************************************************/ 1558 /* async I/Os */ 1559 1560 BlockDriverAIOCB *bdrv_aio_readv(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 (bdrv_check_request(bs, sector_num, nb_sectors)) 1570 return NULL; 1571 1572 ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, 1573 cb, opaque); 1574 1575 if (ret) { 1576 /* Update stats even though technically transfer has not happened. */ 1577 bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE; 1578 bs->rd_ops ++; 1579 } 1580 1581 return ret; 1582 } 1583 1584 BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, 1585 QEMUIOVector *qiov, int nb_sectors, 1586 BlockDriverCompletionFunc *cb, void *opaque) 1587 { 1588 BlockDriver *drv = bs->drv; 1589 BlockDriverAIOCB *ret; 1590 1591 if (!drv) 1592 return NULL; 1593 if (bs->read_only) 1594 return NULL; 1595 if (bdrv_check_request(bs, sector_num, nb_sectors)) 1596 return NULL; 1597 1598 if (bs->dirty_bitmap) { 1599 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 1600 } 1601 1602 ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, 1603 cb, opaque); 1604 1605 if (ret) { 1606 /* Update stats even though technically transfer has not happened. */ 1607 bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE; 1608 bs->wr_ops ++; 1609 } 1610 1611 return ret; 1612 } 1613 1614 1615 typedef struct MultiwriteCB { 1616 int error; 1617 int num_requests; 1618 int num_callbacks; 1619 struct { 1620 BlockDriverCompletionFunc *cb; 1621 void *opaque; 1622 QEMUIOVector *free_qiov; 1623 void *free_buf; 1624 } callbacks[]; 1625 } MultiwriteCB; 1626 1627 static void multiwrite_user_cb(MultiwriteCB *mcb) 1628 { 1629 int i; 1630 1631 for (i = 0; i < mcb->num_callbacks; i++) { 1632 mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); 1633 qemu_free(mcb->callbacks[i].free_qiov); 1634 qemu_free(mcb->callbacks[i].free_buf); 1635 } 1636 } 1637 1638 static void multiwrite_cb(void *opaque, int ret) 1639 { 1640 MultiwriteCB *mcb = opaque; 1641 1642 if (ret < 0) { 1643 mcb->error = ret; 1644 multiwrite_user_cb(mcb); 1645 } 1646 1647 mcb->num_requests--; 1648 if (mcb->num_requests == 0) { 1649 if (mcb->error == 0) { 1650 multiwrite_user_cb(mcb); 1651 } 1652 qemu_free(mcb); 1653 } 1654 } 1655 1656 static int multiwrite_req_compare(const void *a, const void *b) 1657 { 1658 return (((BlockRequest*) a)->sector - ((BlockRequest*) b)->sector); 1659 } 1660 1661 /* 1662 * Takes a bunch of requests and tries to merge them. Returns the number of 1663 * requests that remain after merging. 1664 */ 1665 static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, 1666 int num_reqs, MultiwriteCB *mcb) 1667 { 1668 int i, outidx; 1669 1670 // Sort requests by start sector 1671 qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare); 1672 1673 // Check if adjacent requests touch the same clusters. If so, combine them, 1674 // filling up gaps with zero sectors. 1675 outidx = 0; 1676 for (i = 1; i < num_reqs; i++) { 1677 int merge = 0; 1678 int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; 1679 1680 // This handles the cases that are valid for all block drivers, namely 1681 // exactly sequential writes and overlapping writes. 1682 if (reqs[i].sector <= oldreq_last) { 1683 merge = 1; 1684 } 1685 1686 // The block driver may decide that it makes sense to combine requests 1687 // even if there is a gap of some sectors between them. In this case, 1688 // the gap is filled with zeros (therefore only applicable for yet 1689 // unused space in format like qcow2). 1690 if (!merge && bs->drv->bdrv_merge_requests) { 1691 merge = bs->drv->bdrv_merge_requests(bs, &reqs[outidx], &reqs[i]); 1692 } 1693 1694 if (merge) { 1695 size_t size; 1696 QEMUIOVector *qiov = qemu_mallocz(sizeof(*qiov)); 1697 qemu_iovec_init(qiov, 1698 reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1); 1699 1700 // Add the first request to the merged one. If the requests are 1701 // overlapping, drop the last sectors of the first request. 1702 size = (reqs[i].sector - reqs[outidx].sector) << 9; 1703 qemu_iovec_concat(qiov, reqs[outidx].qiov, size); 1704 1705 // We might need to add some zeros between the two requests 1706 if (reqs[i].sector > oldreq_last) { 1707 size_t zero_bytes = (reqs[i].sector - oldreq_last) << 9; 1708 uint8_t *buf = qemu_blockalign(bs, zero_bytes); 1709 memset(buf, 0, zero_bytes); 1710 qemu_iovec_add(qiov, buf, zero_bytes); 1711 mcb->callbacks[i].free_buf = buf; 1712 } 1713 1714 // Add the second request 1715 qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size); 1716 1717 reqs[outidx].nb_sectors += reqs[i].nb_sectors; 1718 reqs[outidx].qiov = qiov; 1719 1720 mcb->callbacks[i].free_qiov = reqs[outidx].qiov; 1721 } else { 1722 outidx++; 1723 reqs[outidx].sector = reqs[i].sector; 1724 reqs[outidx].nb_sectors = reqs[i].nb_sectors; 1725 reqs[outidx].qiov = reqs[i].qiov; 1726 } 1727 } 1728 1729 return outidx + 1; 1730 } 1731 1732 /* 1733 * Submit multiple AIO write requests at once. 1734 * 1735 * On success, the function returns 0 and all requests in the reqs array have 1736 * been submitted. In error case this function returns -1, and any of the 1737 * requests may or may not be submitted yet. In particular, this means that the 1738 * callback will be called for some of the requests, for others it won't. The 1739 * caller must check the error field of the BlockRequest to wait for the right 1740 * callbacks (if error != 0, no callback will be called). 1741 * 1742 * The implementation may modify the contents of the reqs array, e.g. to merge 1743 * requests. However, the fields opaque and error are left unmodified as they 1744 * are used to signal failure for a single request to the caller. 1745 */ 1746 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) 1747 { 1748 BlockDriverAIOCB *acb; 1749 MultiwriteCB *mcb; 1750 int i; 1751 1752 if (num_reqs == 0) { 1753 return 0; 1754 } 1755 1756 // Create MultiwriteCB structure 1757 mcb = qemu_mallocz(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); 1758 mcb->num_requests = 0; 1759 mcb->num_callbacks = num_reqs; 1760 1761 for (i = 0; i < num_reqs; i++) { 1762 mcb->callbacks[i].cb = reqs[i].cb; 1763 mcb->callbacks[i].opaque = reqs[i].opaque; 1764 } 1765 1766 // Check for mergable requests 1767 num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); 1768 1769 // Run the aio requests 1770 for (i = 0; i < num_reqs; i++) { 1771 acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov, 1772 reqs[i].nb_sectors, multiwrite_cb, mcb); 1773 1774 if (acb == NULL) { 1775 // We can only fail the whole thing if no request has been 1776 // submitted yet. Otherwise we'll wait for the submitted AIOs to 1777 // complete and report the error in the callback. 1778 if (mcb->num_requests == 0) { 1779 reqs[i].error = EIO; 1780 goto fail; 1781 } else { 1782 mcb->error = EIO; 1783 break; 1784 } 1785 } else { 1786 mcb->num_requests++; 1787 } 1788 } 1789 1790 return 0; 1791 1792 fail: 1793 free(mcb); 1794 return -1; 1795 } 1796 1797 BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs, 1798 BlockDriverCompletionFunc *cb, void *opaque) 1799 { 1800 BlockDriver *drv = bs->drv; 1801 1802 if (!drv) 1803 return NULL; 1804 return drv->bdrv_aio_flush(bs, cb, opaque); 1805 } 1806 1807 void bdrv_aio_cancel(BlockDriverAIOCB *acb) 1808 { 1809 acb->pool->cancel(acb); 1810 } 1811 1812 1813 /**************************************************************/ 1814 /* async block device emulation */ 1815 1816 typedef struct BlockDriverAIOCBSync { 1817 BlockDriverAIOCB common; 1818 QEMUBH *bh; 1819 int ret; 1820 /* vector translation state */ 1821 QEMUIOVector *qiov; 1822 uint8_t *bounce; 1823 int is_write; 1824 } BlockDriverAIOCBSync; 1825 1826 static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb) 1827 { 1828 BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb; 1829 qemu_bh_delete(acb->bh); 1830 acb->bh = NULL; 1831 qemu_aio_release(acb); 1832 } 1833 1834 static AIOPool bdrv_em_aio_pool = { 1835 .aiocb_size = sizeof(BlockDriverAIOCBSync), 1836 .cancel = bdrv_aio_cancel_em, 1837 }; 1838 1839 static void bdrv_aio_bh_cb(void *opaque) 1840 { 1841 BlockDriverAIOCBSync *acb = opaque; 1842 1843 if (!acb->is_write) 1844 qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size); 1845 qemu_vfree(acb->bounce); 1846 acb->common.cb(acb->common.opaque, acb->ret); 1847 qemu_bh_delete(acb->bh); 1848 acb->bh = NULL; 1849 qemu_aio_release(acb); 1850 } 1851 1852 static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs, 1853 int64_t sector_num, 1854 QEMUIOVector *qiov, 1855 int nb_sectors, 1856 BlockDriverCompletionFunc *cb, 1857 void *opaque, 1858 int is_write) 1859 1860 { 1861 BlockDriverAIOCBSync *acb; 1862 1863 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 1864 acb->is_write = is_write; 1865 acb->qiov = qiov; 1866 acb->bounce = qemu_blockalign(bs, qiov->size); 1867 1868 if (!acb->bh) 1869 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 1870 1871 if (is_write) { 1872 qemu_iovec_to_buffer(acb->qiov, acb->bounce); 1873 acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors); 1874 } else { 1875 acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors); 1876 } 1877 1878 qemu_bh_schedule(acb->bh); 1879 1880 return &acb->common; 1881 } 1882 1883 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 1884 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 1885 BlockDriverCompletionFunc *cb, void *opaque) 1886 { 1887 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); 1888 } 1889 1890 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 1891 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 1892 BlockDriverCompletionFunc *cb, void *opaque) 1893 { 1894 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); 1895 } 1896 1897 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs, 1898 BlockDriverCompletionFunc *cb, void *opaque) 1899 { 1900 BlockDriverAIOCBSync *acb; 1901 1902 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 1903 acb->is_write = 1; /* don't bounce in the completion hadler */ 1904 acb->qiov = NULL; 1905 acb->bounce = NULL; 1906 acb->ret = 0; 1907 1908 if (!acb->bh) 1909 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 1910 1911 bdrv_flush(bs); 1912 qemu_bh_schedule(acb->bh); 1913 return &acb->common; 1914 } 1915 1916 /**************************************************************/ 1917 /* sync block device emulation */ 1918 1919 static void bdrv_rw_em_cb(void *opaque, int ret) 1920 { 1921 *(int *)opaque = ret; 1922 } 1923 1924 #define NOT_DONE 0x7fffffff 1925 1926 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num, 1927 uint8_t *buf, int nb_sectors) 1928 { 1929 int async_ret; 1930 BlockDriverAIOCB *acb; 1931 struct iovec iov; 1932 QEMUIOVector qiov; 1933 1934 async_context_push(); 1935 1936 async_ret = NOT_DONE; 1937 iov.iov_base = (void *)buf; 1938 iov.iov_len = nb_sectors * 512; 1939 qemu_iovec_init_external(&qiov, &iov, 1); 1940 acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors, 1941 bdrv_rw_em_cb, &async_ret); 1942 if (acb == NULL) { 1943 async_ret = -1; 1944 goto fail; 1945 } 1946 1947 while (async_ret == NOT_DONE) { 1948 qemu_aio_wait(); 1949 } 1950 1951 1952 fail: 1953 async_context_pop(); 1954 return async_ret; 1955 } 1956 1957 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num, 1958 const uint8_t *buf, int nb_sectors) 1959 { 1960 int async_ret; 1961 BlockDriverAIOCB *acb; 1962 struct iovec iov; 1963 QEMUIOVector qiov; 1964 1965 async_context_push(); 1966 1967 async_ret = NOT_DONE; 1968 iov.iov_base = (void *)buf; 1969 iov.iov_len = nb_sectors * 512; 1970 qemu_iovec_init_external(&qiov, &iov, 1); 1971 acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors, 1972 bdrv_rw_em_cb, &async_ret); 1973 if (acb == NULL) { 1974 async_ret = -1; 1975 goto fail; 1976 } 1977 while (async_ret == NOT_DONE) { 1978 qemu_aio_wait(); 1979 } 1980 1981 fail: 1982 async_context_pop(); 1983 return async_ret; 1984 } 1985 1986 void bdrv_init(void) 1987 { 1988 module_call_init(MODULE_INIT_BLOCK); 1989 } 1990 1991 void bdrv_init_with_whitelist(void) 1992 { 1993 use_bdrv_whitelist = 1; 1994 bdrv_init(); 1995 } 1996 1997 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs, 1998 BlockDriverCompletionFunc *cb, void *opaque) 1999 { 2000 BlockDriverAIOCB *acb; 2001 2002 if (pool->free_aiocb) { 2003 acb = pool->free_aiocb; 2004 pool->free_aiocb = acb->next; 2005 } else { 2006 acb = qemu_mallocz(pool->aiocb_size); 2007 acb->pool = pool; 2008 } 2009 acb->bs = bs; 2010 acb->cb = cb; 2011 acb->opaque = opaque; 2012 return acb; 2013 } 2014 2015 void qemu_aio_release(void *p) 2016 { 2017 BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p; 2018 AIOPool *pool = acb->pool; 2019 acb->next = pool->free_aiocb; 2020 pool->free_aiocb = acb; 2021 } 2022 2023 /**************************************************************/ 2024 /* removable device support */ 2025 2026 /** 2027 * Return TRUE if the media is present 2028 */ 2029 int bdrv_is_inserted(BlockDriverState *bs) 2030 { 2031 BlockDriver *drv = bs->drv; 2032 int ret; 2033 if (!drv) 2034 return 0; 2035 if (!drv->bdrv_is_inserted) 2036 return 1; 2037 ret = drv->bdrv_is_inserted(bs); 2038 return ret; 2039 } 2040 2041 /** 2042 * Return TRUE if the media changed since the last call to this 2043 * function. It is currently only used for floppy disks 2044 */ 2045 int bdrv_media_changed(BlockDriverState *bs) 2046 { 2047 BlockDriver *drv = bs->drv; 2048 int ret; 2049 2050 if (!drv || !drv->bdrv_media_changed) 2051 ret = -ENOTSUP; 2052 else 2053 ret = drv->bdrv_media_changed(bs); 2054 if (ret == -ENOTSUP) 2055 ret = bs->media_changed; 2056 bs->media_changed = 0; 2057 return ret; 2058 } 2059 2060 /** 2061 * If eject_flag is TRUE, eject the media. Otherwise, close the tray 2062 */ 2063 int bdrv_eject(BlockDriverState *bs, int eject_flag) 2064 { 2065 BlockDriver *drv = bs->drv; 2066 int ret; 2067 2068 if (bs->locked) { 2069 return -EBUSY; 2070 } 2071 2072 if (!drv || !drv->bdrv_eject) { 2073 ret = -ENOTSUP; 2074 } else { 2075 ret = drv->bdrv_eject(bs, eject_flag); 2076 } 2077 if (ret == -ENOTSUP) { 2078 if (eject_flag) 2079 bdrv_close(bs); 2080 ret = 0; 2081 } 2082 2083 return ret; 2084 } 2085 2086 int bdrv_is_locked(BlockDriverState *bs) 2087 { 2088 return bs->locked; 2089 } 2090 2091 /** 2092 * Lock or unlock the media (if it is locked, the user won't be able 2093 * to eject it manually). 2094 */ 2095 void bdrv_set_locked(BlockDriverState *bs, int locked) 2096 { 2097 BlockDriver *drv = bs->drv; 2098 2099 bs->locked = locked; 2100 if (drv && drv->bdrv_set_locked) { 2101 drv->bdrv_set_locked(bs, locked); 2102 } 2103 } 2104 2105 /* needed for generic scsi interface */ 2106 2107 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) 2108 { 2109 BlockDriver *drv = bs->drv; 2110 2111 if (drv && drv->bdrv_ioctl) 2112 return drv->bdrv_ioctl(bs, req, buf); 2113 return -ENOTSUP; 2114 } 2115 2116 BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, 2117 unsigned long int req, void *buf, 2118 BlockDriverCompletionFunc *cb, void *opaque) 2119 { 2120 BlockDriver *drv = bs->drv; 2121 2122 if (drv && drv->bdrv_aio_ioctl) 2123 return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); 2124 return NULL; 2125 } 2126 2127 2128 2129 void *qemu_blockalign(BlockDriverState *bs, size_t size) 2130 { 2131 return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size); 2132 } 2133 2134 void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable) 2135 { 2136 int64_t bitmap_size; 2137 2138 if (enable) { 2139 if (!bs->dirty_bitmap) { 2140 bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) + 2141 BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1; 2142 bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8; 2143 2144 bs->dirty_bitmap = qemu_mallocz(bitmap_size); 2145 } 2146 } else { 2147 if (bs->dirty_bitmap) { 2148 qemu_free(bs->dirty_bitmap); 2149 bs->dirty_bitmap = NULL; 2150 } 2151 } 2152 } 2153 2154 int bdrv_get_dirty(BlockDriverState *bs, int64_t sector) 2155 { 2156 int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK; 2157 2158 if (bs->dirty_bitmap && 2159 (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) { 2160 return bs->dirty_bitmap[chunk / (sizeof(unsigned long) * 8)] & 2161 (1 << (chunk % (sizeof(unsigned long) * 8))); 2162 } else { 2163 return 0; 2164 } 2165 } 2166 2167 void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, 2168 int nr_sectors) 2169 { 2170 set_dirty_bitmap(bs, cur_sector, nr_sectors, 0); 2171 } 2172