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 /* 601 * Return values: 602 * 0 - success 603 * -EINVAL - backing format specified, but no file 604 * -ENOSPC - can't update the backing file because no space is left in the 605 * image file header 606 * -ENOTSUP - format driver doesn't support changing the backing file 607 */ 608 int bdrv_change_backing_file(BlockDriverState *bs, 609 const char *backing_file, const char *backing_fmt) 610 { 611 BlockDriver *drv = bs->drv; 612 613 if (drv->bdrv_change_backing_file != NULL) { 614 return drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); 615 } else { 616 return -ENOTSUP; 617 } 618 } 619 620 static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 621 size_t size) 622 { 623 int64_t len; 624 625 if (!bdrv_is_inserted(bs)) 626 return -ENOMEDIUM; 627 628 if (bs->growable) 629 return 0; 630 631 len = bdrv_getlength(bs); 632 633 if (offset < 0) 634 return -EIO; 635 636 if ((offset > len) || (len - offset < size)) 637 return -EIO; 638 639 return 0; 640 } 641 642 static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, 643 int nb_sectors) 644 { 645 return bdrv_check_byte_request(bs, sector_num * 512, nb_sectors * 512); 646 } 647 648 /* return < 0 if error. See bdrv_write() for the return codes */ 649 int bdrv_read(BlockDriverState *bs, int64_t sector_num, 650 uint8_t *buf, int nb_sectors) 651 { 652 BlockDriver *drv = bs->drv; 653 654 if (!drv) 655 return -ENOMEDIUM; 656 if (bdrv_check_request(bs, sector_num, nb_sectors)) 657 return -EIO; 658 659 return drv->bdrv_read(bs, sector_num, buf, nb_sectors); 660 } 661 662 static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num, 663 int nb_sectors, int dirty) 664 { 665 int64_t start, end; 666 unsigned long val, idx, bit; 667 668 start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK; 669 end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK; 670 671 for (; start <= end; start++) { 672 idx = start / (sizeof(unsigned long) * 8); 673 bit = start % (sizeof(unsigned long) * 8); 674 val = bs->dirty_bitmap[idx]; 675 if (dirty) { 676 val |= 1 << bit; 677 } else { 678 val &= ~(1 << bit); 679 } 680 bs->dirty_bitmap[idx] = val; 681 } 682 } 683 684 /* Return < 0 if error. Important errors are: 685 -EIO generic I/O error (may happen for all errors) 686 -ENOMEDIUM No media inserted. 687 -EINVAL Invalid sector number or nb_sectors 688 -EACCES Trying to write a read-only device 689 */ 690 int bdrv_write(BlockDriverState *bs, int64_t sector_num, 691 const uint8_t *buf, int nb_sectors) 692 { 693 BlockDriver *drv = bs->drv; 694 if (!bs->drv) 695 return -ENOMEDIUM; 696 if (bs->read_only) 697 return -EACCES; 698 if (bdrv_check_request(bs, sector_num, nb_sectors)) 699 return -EIO; 700 701 if (bs->dirty_bitmap) { 702 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 703 } 704 705 return drv->bdrv_write(bs, sector_num, buf, nb_sectors); 706 } 707 708 int bdrv_pread(BlockDriverState *bs, int64_t offset, 709 void *buf, int count1) 710 { 711 uint8_t tmp_buf[BDRV_SECTOR_SIZE]; 712 int len, nb_sectors, count; 713 int64_t sector_num; 714 715 count = count1; 716 /* first read to align to sector start */ 717 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); 718 if (len > count) 719 len = count; 720 sector_num = offset >> BDRV_SECTOR_BITS; 721 if (len > 0) { 722 if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0) 723 return -EIO; 724 memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len); 725 count -= len; 726 if (count == 0) 727 return count1; 728 sector_num++; 729 buf += len; 730 } 731 732 /* read the sectors "in place" */ 733 nb_sectors = count >> BDRV_SECTOR_BITS; 734 if (nb_sectors > 0) { 735 if (bdrv_read(bs, sector_num, buf, nb_sectors) < 0) 736 return -EIO; 737 sector_num += nb_sectors; 738 len = nb_sectors << BDRV_SECTOR_BITS; 739 buf += len; 740 count -= len; 741 } 742 743 /* add data from the last sector */ 744 if (count > 0) { 745 if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0) 746 return -EIO; 747 memcpy(buf, tmp_buf, count); 748 } 749 return count1; 750 } 751 752 int bdrv_pwrite(BlockDriverState *bs, int64_t offset, 753 const void *buf, int count1) 754 { 755 uint8_t tmp_buf[BDRV_SECTOR_SIZE]; 756 int len, nb_sectors, count; 757 int64_t sector_num; 758 759 count = count1; 760 /* first write to align to sector start */ 761 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); 762 if (len > count) 763 len = count; 764 sector_num = offset >> BDRV_SECTOR_BITS; 765 if (len > 0) { 766 if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0) 767 return -EIO; 768 memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len); 769 if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0) 770 return -EIO; 771 count -= len; 772 if (count == 0) 773 return count1; 774 sector_num++; 775 buf += len; 776 } 777 778 /* write the sectors "in place" */ 779 nb_sectors = count >> BDRV_SECTOR_BITS; 780 if (nb_sectors > 0) { 781 if (bdrv_write(bs, sector_num, buf, nb_sectors) < 0) 782 return -EIO; 783 sector_num += nb_sectors; 784 len = nb_sectors << BDRV_SECTOR_BITS; 785 buf += len; 786 count -= len; 787 } 788 789 /* add data from the last sector */ 790 if (count > 0) { 791 if (bdrv_read(bs, sector_num, tmp_buf, 1) < 0) 792 return -EIO; 793 memcpy(tmp_buf, buf, count); 794 if (bdrv_write(bs, sector_num, tmp_buf, 1) < 0) 795 return -EIO; 796 } 797 return count1; 798 } 799 800 /** 801 * Truncate file to 'offset' bytes (needed only for file protocols) 802 */ 803 int bdrv_truncate(BlockDriverState *bs, int64_t offset) 804 { 805 BlockDriver *drv = bs->drv; 806 if (!drv) 807 return -ENOMEDIUM; 808 if (!drv->bdrv_truncate) 809 return -ENOTSUP; 810 if (bs->read_only) 811 return -EACCES; 812 return drv->bdrv_truncate(bs, offset); 813 } 814 815 /** 816 * Length of a file in bytes. Return < 0 if error or unknown. 817 */ 818 int64_t bdrv_getlength(BlockDriverState *bs) 819 { 820 BlockDriver *drv = bs->drv; 821 if (!drv) 822 return -ENOMEDIUM; 823 if (!drv->bdrv_getlength) { 824 /* legacy mode */ 825 return bs->total_sectors * BDRV_SECTOR_SIZE; 826 } 827 return drv->bdrv_getlength(bs); 828 } 829 830 /* return 0 as number of sectors if no device present or error */ 831 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr) 832 { 833 int64_t length; 834 length = bdrv_getlength(bs); 835 if (length < 0) 836 length = 0; 837 else 838 length = length >> BDRV_SECTOR_BITS; 839 *nb_sectors_ptr = length; 840 } 841 842 struct partition { 843 uint8_t boot_ind; /* 0x80 - active */ 844 uint8_t head; /* starting head */ 845 uint8_t sector; /* starting sector */ 846 uint8_t cyl; /* starting cylinder */ 847 uint8_t sys_ind; /* What partition type */ 848 uint8_t end_head; /* end head */ 849 uint8_t end_sector; /* end sector */ 850 uint8_t end_cyl; /* end cylinder */ 851 uint32_t start_sect; /* starting sector counting from 0 */ 852 uint32_t nr_sects; /* nr of sectors in partition */ 853 } __attribute__((packed)); 854 855 /* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */ 856 static int guess_disk_lchs(BlockDriverState *bs, 857 int *pcylinders, int *pheads, int *psectors) 858 { 859 uint8_t buf[512]; 860 int ret, i, heads, sectors, cylinders; 861 struct partition *p; 862 uint32_t nr_sects; 863 uint64_t nb_sectors; 864 865 bdrv_get_geometry(bs, &nb_sectors); 866 867 ret = bdrv_read(bs, 0, buf, 1); 868 if (ret < 0) 869 return -1; 870 /* test msdos magic */ 871 if (buf[510] != 0x55 || buf[511] != 0xaa) 872 return -1; 873 for(i = 0; i < 4; i++) { 874 p = ((struct partition *)(buf + 0x1be)) + i; 875 nr_sects = le32_to_cpu(p->nr_sects); 876 if (nr_sects && p->end_head) { 877 /* We make the assumption that the partition terminates on 878 a cylinder boundary */ 879 heads = p->end_head + 1; 880 sectors = p->end_sector & 63; 881 if (sectors == 0) 882 continue; 883 cylinders = nb_sectors / (heads * sectors); 884 if (cylinders < 1 || cylinders > 16383) 885 continue; 886 *pheads = heads; 887 *psectors = sectors; 888 *pcylinders = cylinders; 889 #if 0 890 printf("guessed geometry: LCHS=%d %d %d\n", 891 cylinders, heads, sectors); 892 #endif 893 return 0; 894 } 895 } 896 return -1; 897 } 898 899 void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs) 900 { 901 int translation, lba_detected = 0; 902 int cylinders, heads, secs; 903 uint64_t nb_sectors; 904 905 /* if a geometry hint is available, use it */ 906 bdrv_get_geometry(bs, &nb_sectors); 907 bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs); 908 translation = bdrv_get_translation_hint(bs); 909 if (cylinders != 0) { 910 *pcyls = cylinders; 911 *pheads = heads; 912 *psecs = secs; 913 } else { 914 if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) { 915 if (heads > 16) { 916 /* if heads > 16, it means that a BIOS LBA 917 translation was active, so the default 918 hardware geometry is OK */ 919 lba_detected = 1; 920 goto default_geometry; 921 } else { 922 *pcyls = cylinders; 923 *pheads = heads; 924 *psecs = secs; 925 /* disable any translation to be in sync with 926 the logical geometry */ 927 if (translation == BIOS_ATA_TRANSLATION_AUTO) { 928 bdrv_set_translation_hint(bs, 929 BIOS_ATA_TRANSLATION_NONE); 930 } 931 } 932 } else { 933 default_geometry: 934 /* if no geometry, use a standard physical disk geometry */ 935 cylinders = nb_sectors / (16 * 63); 936 937 if (cylinders > 16383) 938 cylinders = 16383; 939 else if (cylinders < 2) 940 cylinders = 2; 941 *pcyls = cylinders; 942 *pheads = 16; 943 *psecs = 63; 944 if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) { 945 if ((*pcyls * *pheads) <= 131072) { 946 bdrv_set_translation_hint(bs, 947 BIOS_ATA_TRANSLATION_LARGE); 948 } else { 949 bdrv_set_translation_hint(bs, 950 BIOS_ATA_TRANSLATION_LBA); 951 } 952 } 953 } 954 bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs); 955 } 956 } 957 958 void bdrv_set_geometry_hint(BlockDriverState *bs, 959 int cyls, int heads, int secs) 960 { 961 bs->cyls = cyls; 962 bs->heads = heads; 963 bs->secs = secs; 964 } 965 966 void bdrv_set_type_hint(BlockDriverState *bs, int type) 967 { 968 bs->type = type; 969 bs->removable = ((type == BDRV_TYPE_CDROM || 970 type == BDRV_TYPE_FLOPPY)); 971 } 972 973 void bdrv_set_translation_hint(BlockDriverState *bs, int translation) 974 { 975 bs->translation = translation; 976 } 977 978 void bdrv_get_geometry_hint(BlockDriverState *bs, 979 int *pcyls, int *pheads, int *psecs) 980 { 981 *pcyls = bs->cyls; 982 *pheads = bs->heads; 983 *psecs = bs->secs; 984 } 985 986 int bdrv_get_type_hint(BlockDriverState *bs) 987 { 988 return bs->type; 989 } 990 991 int bdrv_get_translation_hint(BlockDriverState *bs) 992 { 993 return bs->translation; 994 } 995 996 int bdrv_is_removable(BlockDriverState *bs) 997 { 998 return bs->removable; 999 } 1000 1001 int bdrv_is_read_only(BlockDriverState *bs) 1002 { 1003 return bs->read_only; 1004 } 1005 1006 int bdrv_set_read_only(BlockDriverState *bs, int read_only) 1007 { 1008 int ret = bs->read_only; 1009 bs->read_only = read_only; 1010 return ret; 1011 } 1012 1013 int bdrv_is_sg(BlockDriverState *bs) 1014 { 1015 return bs->sg; 1016 } 1017 1018 int bdrv_enable_write_cache(BlockDriverState *bs) 1019 { 1020 return bs->enable_write_cache; 1021 } 1022 1023 /* XXX: no longer used */ 1024 void bdrv_set_change_cb(BlockDriverState *bs, 1025 void (*change_cb)(void *opaque), void *opaque) 1026 { 1027 bs->change_cb = change_cb; 1028 bs->change_opaque = opaque; 1029 } 1030 1031 int bdrv_is_encrypted(BlockDriverState *bs) 1032 { 1033 if (bs->backing_hd && bs->backing_hd->encrypted) 1034 return 1; 1035 return bs->encrypted; 1036 } 1037 1038 int bdrv_key_required(BlockDriverState *bs) 1039 { 1040 BlockDriverState *backing_hd = bs->backing_hd; 1041 1042 if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key) 1043 return 1; 1044 return (bs->encrypted && !bs->valid_key); 1045 } 1046 1047 int bdrv_set_key(BlockDriverState *bs, const char *key) 1048 { 1049 int ret; 1050 if (bs->backing_hd && bs->backing_hd->encrypted) { 1051 ret = bdrv_set_key(bs->backing_hd, key); 1052 if (ret < 0) 1053 return ret; 1054 if (!bs->encrypted) 1055 return 0; 1056 } 1057 if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key) 1058 return -1; 1059 ret = bs->drv->bdrv_set_key(bs, key); 1060 if (ret < 0) { 1061 bs->valid_key = 0; 1062 } else if (!bs->valid_key) { 1063 bs->valid_key = 1; 1064 /* call the change callback now, we skipped it on open */ 1065 bs->media_changed = 1; 1066 if (bs->change_cb) 1067 bs->change_cb(bs->change_opaque); 1068 } 1069 return ret; 1070 } 1071 1072 void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size) 1073 { 1074 if (!bs->drv) { 1075 buf[0] = '\0'; 1076 } else { 1077 pstrcpy(buf, buf_size, bs->drv->format_name); 1078 } 1079 } 1080 1081 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 1082 void *opaque) 1083 { 1084 BlockDriver *drv; 1085 1086 for (drv = first_drv; drv != NULL; drv = drv->next) { 1087 it(opaque, drv->format_name); 1088 } 1089 } 1090 1091 BlockDriverState *bdrv_find(const char *name) 1092 { 1093 BlockDriverState *bs; 1094 1095 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1096 if (!strcmp(name, bs->device_name)) 1097 return bs; 1098 } 1099 return NULL; 1100 } 1101 1102 void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque) 1103 { 1104 BlockDriverState *bs; 1105 1106 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1107 it(opaque, bs); 1108 } 1109 } 1110 1111 const char *bdrv_get_device_name(BlockDriverState *bs) 1112 { 1113 return bs->device_name; 1114 } 1115 1116 void bdrv_flush(BlockDriverState *bs) 1117 { 1118 if (!bs->drv) 1119 return; 1120 if (bs->drv->bdrv_flush) 1121 bs->drv->bdrv_flush(bs); 1122 if (bs->backing_hd) 1123 bdrv_flush(bs->backing_hd); 1124 } 1125 1126 void bdrv_flush_all(void) 1127 { 1128 BlockDriverState *bs; 1129 1130 for (bs = bdrv_first; bs != NULL; bs = bs->next) 1131 if (bs->drv && !bdrv_is_read_only(bs) && 1132 (!bdrv_is_removable(bs) || bdrv_is_inserted(bs))) 1133 bdrv_flush(bs); 1134 } 1135 1136 /* 1137 * Returns true iff the specified sector is present in the disk image. Drivers 1138 * not implementing the functionality are assumed to not support backing files, 1139 * hence all their sectors are reported as allocated. 1140 * 1141 * 'pnum' is set to the number of sectors (including and immediately following 1142 * the specified sector) that are known to be in the same 1143 * allocated/unallocated state. 1144 * 1145 * 'nb_sectors' is the max value 'pnum' should be set to. 1146 */ 1147 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, 1148 int *pnum) 1149 { 1150 int64_t n; 1151 if (!bs->drv->bdrv_is_allocated) { 1152 if (sector_num >= bs->total_sectors) { 1153 *pnum = 0; 1154 return 0; 1155 } 1156 n = bs->total_sectors - sector_num; 1157 *pnum = (n < nb_sectors) ? (n) : (nb_sectors); 1158 return 1; 1159 } 1160 return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum); 1161 } 1162 1163 static void bdrv_print_dict(QObject *obj, void *opaque) 1164 { 1165 QDict *bs_dict; 1166 Monitor *mon = opaque; 1167 1168 bs_dict = qobject_to_qdict(obj); 1169 1170 monitor_printf(mon, "%s: type=%s removable=%d", 1171 qdict_get_str(bs_dict, "device"), 1172 qdict_get_str(bs_dict, "type"), 1173 qdict_get_bool(bs_dict, "removable")); 1174 1175 if (qdict_get_bool(bs_dict, "removable")) { 1176 monitor_printf(mon, " locked=%d", qdict_get_bool(bs_dict, "locked")); 1177 } 1178 1179 if (qdict_haskey(bs_dict, "inserted")) { 1180 QDict *qdict = qobject_to_qdict(qdict_get(bs_dict, "inserted")); 1181 1182 monitor_printf(mon, " file="); 1183 monitor_print_filename(mon, qdict_get_str(qdict, "file")); 1184 if (qdict_haskey(qdict, "backing_file")) { 1185 monitor_printf(mon, " backing_file="); 1186 monitor_print_filename(mon, qdict_get_str(qdict, "backing_file")); 1187 } 1188 monitor_printf(mon, " ro=%d drv=%s encrypted=%d", 1189 qdict_get_bool(qdict, "ro"), 1190 qdict_get_str(qdict, "drv"), 1191 qdict_get_bool(qdict, "encrypted")); 1192 } else { 1193 monitor_printf(mon, " [not inserted]"); 1194 } 1195 1196 monitor_printf(mon, "\n"); 1197 } 1198 1199 void bdrv_info_print(Monitor *mon, const QObject *data) 1200 { 1201 qlist_iter(qobject_to_qlist(data), bdrv_print_dict, mon); 1202 } 1203 1204 /** 1205 * bdrv_info(): Block devices information 1206 * 1207 * Each block device information is stored in a QDict and the 1208 * returned QObject is a QList of all devices. 1209 * 1210 * The QDict contains the following: 1211 * 1212 * - "device": device name 1213 * - "type": device type 1214 * - "removable": true if the device is removable, false otherwise 1215 * - "locked": true if the device is locked, false otherwise 1216 * - "inserted": only present if the device is inserted, it is a QDict 1217 * containing the following: 1218 * - "file": device file name 1219 * - "ro": true if read-only, false otherwise 1220 * - "drv": driver format name 1221 * - "backing_file": backing file name if one is used 1222 * - "encrypted": true if encrypted, false otherwise 1223 * 1224 * Example: 1225 * 1226 * [ { "device": "ide0-hd0", "type": "hd", "removable": false, "locked": false, 1227 * "inserted": { "file": "/tmp/foobar", "ro": false, "drv": "qcow2" } }, 1228 * { "device": "floppy0", "type": "floppy", "removable": true, 1229 * "locked": false } ] 1230 */ 1231 void bdrv_info(Monitor *mon, QObject **ret_data) 1232 { 1233 QList *bs_list; 1234 BlockDriverState *bs; 1235 1236 bs_list = qlist_new(); 1237 1238 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1239 QObject *bs_obj; 1240 const char *type = "unknown"; 1241 1242 switch(bs->type) { 1243 case BDRV_TYPE_HD: 1244 type = "hd"; 1245 break; 1246 case BDRV_TYPE_CDROM: 1247 type = "cdrom"; 1248 break; 1249 case BDRV_TYPE_FLOPPY: 1250 type = "floppy"; 1251 break; 1252 } 1253 1254 bs_obj = qobject_from_jsonf("{ 'device': %s, 'type': %s, " 1255 "'removable': %i, 'locked': %i }", 1256 bs->device_name, type, bs->removable, 1257 bs->locked); 1258 assert(bs_obj != NULL); 1259 1260 if (bs->drv) { 1261 QObject *obj; 1262 QDict *bs_dict = qobject_to_qdict(bs_obj); 1263 1264 obj = qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, " 1265 "'encrypted': %i }", 1266 bs->filename, bs->read_only, 1267 bs->drv->format_name, 1268 bdrv_is_encrypted(bs)); 1269 assert(obj != NULL); 1270 if (bs->backing_file[0] != '\0') { 1271 QDict *qdict = qobject_to_qdict(obj); 1272 qdict_put(qdict, "backing_file", 1273 qstring_from_str(bs->backing_file)); 1274 } 1275 1276 qdict_put_obj(bs_dict, "inserted", obj); 1277 } 1278 qlist_append_obj(bs_list, bs_obj); 1279 } 1280 1281 *ret_data = QOBJECT(bs_list); 1282 } 1283 1284 static void bdrv_stats_iter(QObject *data, void *opaque) 1285 { 1286 QDict *qdict; 1287 Monitor *mon = opaque; 1288 1289 qdict = qobject_to_qdict(data); 1290 monitor_printf(mon, "%s:", qdict_get_str(qdict, "device")); 1291 1292 qdict = qobject_to_qdict(qdict_get(qdict, "stats")); 1293 monitor_printf(mon, " rd_bytes=%" PRId64 1294 " wr_bytes=%" PRId64 1295 " rd_operations=%" PRId64 1296 " wr_operations=%" PRId64 1297 "\n", 1298 qdict_get_int(qdict, "rd_bytes"), 1299 qdict_get_int(qdict, "wr_bytes"), 1300 qdict_get_int(qdict, "rd_operations"), 1301 qdict_get_int(qdict, "wr_operations")); 1302 } 1303 1304 void bdrv_stats_print(Monitor *mon, const QObject *data) 1305 { 1306 qlist_iter(qobject_to_qlist(data), bdrv_stats_iter, mon); 1307 } 1308 1309 /** 1310 * bdrv_info_stats(): show block device statistics 1311 * 1312 * Each device statistic information is stored in a QDict and 1313 * the returned QObject is a QList of all devices. 1314 * 1315 * The QDict contains the following: 1316 * 1317 * - "device": device name 1318 * - "stats": A QDict with the statistics information, it contains: 1319 * - "rd_bytes": bytes read 1320 * - "wr_bytes": bytes written 1321 * - "rd_operations": read operations 1322 * - "wr_operations": write operations 1323 * 1324 * Example: 1325 * 1326 * [ { "device": "ide0-hd0", 1327 * "stats": { "rd_bytes": 512, 1328 * "wr_bytes": 0, 1329 * "rd_operations": 1, 1330 * "wr_operations": 0 } }, 1331 * { "device": "ide1-cd0", 1332 * "stats": { "rd_bytes": 0, 1333 * "wr_bytes": 0, 1334 * "rd_operations": 0, 1335 * "wr_operations": 0 } } ] 1336 */ 1337 void bdrv_info_stats(Monitor *mon, QObject **ret_data) 1338 { 1339 QObject *obj; 1340 QList *devices; 1341 BlockDriverState *bs; 1342 1343 devices = qlist_new(); 1344 1345 for (bs = bdrv_first; bs != NULL; bs = bs->next) { 1346 obj = qobject_from_jsonf("{ 'device': %s, 'stats': {" 1347 "'rd_bytes': %" PRId64 "," 1348 "'wr_bytes': %" PRId64 "," 1349 "'rd_operations': %" PRId64 "," 1350 "'wr_operations': %" PRId64 1351 "} }", 1352 bs->device_name, 1353 bs->rd_bytes, bs->wr_bytes, 1354 bs->rd_ops, bs->wr_ops); 1355 assert(obj != NULL); 1356 qlist_append_obj(devices, obj); 1357 } 1358 1359 *ret_data = QOBJECT(devices); 1360 } 1361 1362 const char *bdrv_get_encrypted_filename(BlockDriverState *bs) 1363 { 1364 if (bs->backing_hd && bs->backing_hd->encrypted) 1365 return bs->backing_file; 1366 else if (bs->encrypted) 1367 return bs->filename; 1368 else 1369 return NULL; 1370 } 1371 1372 void bdrv_get_backing_filename(BlockDriverState *bs, 1373 char *filename, int filename_size) 1374 { 1375 if (!bs->backing_file) { 1376 pstrcpy(filename, filename_size, ""); 1377 } else { 1378 pstrcpy(filename, filename_size, bs->backing_file); 1379 } 1380 } 1381 1382 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num, 1383 const uint8_t *buf, int nb_sectors) 1384 { 1385 BlockDriver *drv = bs->drv; 1386 if (!drv) 1387 return -ENOMEDIUM; 1388 if (!drv->bdrv_write_compressed) 1389 return -ENOTSUP; 1390 if (bdrv_check_request(bs, sector_num, nb_sectors)) 1391 return -EIO; 1392 1393 if (bs->dirty_bitmap) { 1394 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 1395 } 1396 1397 return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors); 1398 } 1399 1400 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1401 { 1402 BlockDriver *drv = bs->drv; 1403 if (!drv) 1404 return -ENOMEDIUM; 1405 if (!drv->bdrv_get_info) 1406 return -ENOTSUP; 1407 memset(bdi, 0, sizeof(*bdi)); 1408 return drv->bdrv_get_info(bs, bdi); 1409 } 1410 1411 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 1412 int64_t pos, int size) 1413 { 1414 BlockDriver *drv = bs->drv; 1415 if (!drv) 1416 return -ENOMEDIUM; 1417 if (!drv->bdrv_save_vmstate) 1418 return -ENOTSUP; 1419 return drv->bdrv_save_vmstate(bs, buf, pos, size); 1420 } 1421 1422 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 1423 int64_t pos, int size) 1424 { 1425 BlockDriver *drv = bs->drv; 1426 if (!drv) 1427 return -ENOMEDIUM; 1428 if (!drv->bdrv_load_vmstate) 1429 return -ENOTSUP; 1430 return drv->bdrv_load_vmstate(bs, buf, pos, size); 1431 } 1432 1433 /**************************************************************/ 1434 /* handling of snapshots */ 1435 1436 int bdrv_snapshot_create(BlockDriverState *bs, 1437 QEMUSnapshotInfo *sn_info) 1438 { 1439 BlockDriver *drv = bs->drv; 1440 if (!drv) 1441 return -ENOMEDIUM; 1442 if (!drv->bdrv_snapshot_create) 1443 return -ENOTSUP; 1444 return drv->bdrv_snapshot_create(bs, sn_info); 1445 } 1446 1447 int bdrv_snapshot_goto(BlockDriverState *bs, 1448 const char *snapshot_id) 1449 { 1450 BlockDriver *drv = bs->drv; 1451 if (!drv) 1452 return -ENOMEDIUM; 1453 if (!drv->bdrv_snapshot_goto) 1454 return -ENOTSUP; 1455 return drv->bdrv_snapshot_goto(bs, snapshot_id); 1456 } 1457 1458 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) 1459 { 1460 BlockDriver *drv = bs->drv; 1461 if (!drv) 1462 return -ENOMEDIUM; 1463 if (!drv->bdrv_snapshot_delete) 1464 return -ENOTSUP; 1465 return drv->bdrv_snapshot_delete(bs, snapshot_id); 1466 } 1467 1468 int bdrv_snapshot_list(BlockDriverState *bs, 1469 QEMUSnapshotInfo **psn_info) 1470 { 1471 BlockDriver *drv = bs->drv; 1472 if (!drv) 1473 return -ENOMEDIUM; 1474 if (!drv->bdrv_snapshot_list) 1475 return -ENOTSUP; 1476 return drv->bdrv_snapshot_list(bs, psn_info); 1477 } 1478 1479 #define NB_SUFFIXES 4 1480 1481 char *get_human_readable_size(char *buf, int buf_size, int64_t size) 1482 { 1483 static const char suffixes[NB_SUFFIXES] = "KMGT"; 1484 int64_t base; 1485 int i; 1486 1487 if (size <= 999) { 1488 snprintf(buf, buf_size, "%" PRId64, size); 1489 } else { 1490 base = 1024; 1491 for(i = 0; i < NB_SUFFIXES; i++) { 1492 if (size < (10 * base)) { 1493 snprintf(buf, buf_size, "%0.1f%c", 1494 (double)size / base, 1495 suffixes[i]); 1496 break; 1497 } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) { 1498 snprintf(buf, buf_size, "%" PRId64 "%c", 1499 ((size + (base >> 1)) / base), 1500 suffixes[i]); 1501 break; 1502 } 1503 base = base * 1024; 1504 } 1505 } 1506 return buf; 1507 } 1508 1509 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn) 1510 { 1511 char buf1[128], date_buf[128], clock_buf[128]; 1512 #ifdef _WIN32 1513 struct tm *ptm; 1514 #else 1515 struct tm tm; 1516 #endif 1517 time_t ti; 1518 int64_t secs; 1519 1520 if (!sn) { 1521 snprintf(buf, buf_size, 1522 "%-10s%-20s%7s%20s%15s", 1523 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK"); 1524 } else { 1525 ti = sn->date_sec; 1526 #ifdef _WIN32 1527 ptm = localtime(&ti); 1528 strftime(date_buf, sizeof(date_buf), 1529 "%Y-%m-%d %H:%M:%S", ptm); 1530 #else 1531 localtime_r(&ti, &tm); 1532 strftime(date_buf, sizeof(date_buf), 1533 "%Y-%m-%d %H:%M:%S", &tm); 1534 #endif 1535 secs = sn->vm_clock_nsec / 1000000000; 1536 snprintf(clock_buf, sizeof(clock_buf), 1537 "%02d:%02d:%02d.%03d", 1538 (int)(secs / 3600), 1539 (int)((secs / 60) % 60), 1540 (int)(secs % 60), 1541 (int)((sn->vm_clock_nsec / 1000000) % 1000)); 1542 snprintf(buf, buf_size, 1543 "%-10s%-20s%7s%20s%15s", 1544 sn->id_str, sn->name, 1545 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size), 1546 date_buf, 1547 clock_buf); 1548 } 1549 return buf; 1550 } 1551 1552 1553 /**************************************************************/ 1554 /* async I/Os */ 1555 1556 BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, 1557 QEMUIOVector *qiov, int nb_sectors, 1558 BlockDriverCompletionFunc *cb, void *opaque) 1559 { 1560 BlockDriver *drv = bs->drv; 1561 BlockDriverAIOCB *ret; 1562 1563 if (!drv) 1564 return NULL; 1565 if (bdrv_check_request(bs, sector_num, nb_sectors)) 1566 return NULL; 1567 1568 ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, 1569 cb, opaque); 1570 1571 if (ret) { 1572 /* Update stats even though technically transfer has not happened. */ 1573 bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE; 1574 bs->rd_ops ++; 1575 } 1576 1577 return ret; 1578 } 1579 1580 BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, 1581 QEMUIOVector *qiov, int nb_sectors, 1582 BlockDriverCompletionFunc *cb, void *opaque) 1583 { 1584 BlockDriver *drv = bs->drv; 1585 BlockDriverAIOCB *ret; 1586 1587 if (!drv) 1588 return NULL; 1589 if (bs->read_only) 1590 return NULL; 1591 if (bdrv_check_request(bs, sector_num, nb_sectors)) 1592 return NULL; 1593 1594 if (bs->dirty_bitmap) { 1595 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 1596 } 1597 1598 ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, 1599 cb, opaque); 1600 1601 if (ret) { 1602 /* Update stats even though technically transfer has not happened. */ 1603 bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE; 1604 bs->wr_ops ++; 1605 } 1606 1607 return ret; 1608 } 1609 1610 1611 typedef struct MultiwriteCB { 1612 int error; 1613 int num_requests; 1614 int num_callbacks; 1615 struct { 1616 BlockDriverCompletionFunc *cb; 1617 void *opaque; 1618 QEMUIOVector *free_qiov; 1619 void *free_buf; 1620 } callbacks[]; 1621 } MultiwriteCB; 1622 1623 static void multiwrite_user_cb(MultiwriteCB *mcb) 1624 { 1625 int i; 1626 1627 for (i = 0; i < mcb->num_callbacks; i++) { 1628 mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); 1629 qemu_free(mcb->callbacks[i].free_qiov); 1630 qemu_free(mcb->callbacks[i].free_buf); 1631 } 1632 } 1633 1634 static void multiwrite_cb(void *opaque, int ret) 1635 { 1636 MultiwriteCB *mcb = opaque; 1637 1638 if (ret < 0) { 1639 mcb->error = ret; 1640 multiwrite_user_cb(mcb); 1641 } 1642 1643 mcb->num_requests--; 1644 if (mcb->num_requests == 0) { 1645 if (mcb->error == 0) { 1646 multiwrite_user_cb(mcb); 1647 } 1648 qemu_free(mcb); 1649 } 1650 } 1651 1652 static int multiwrite_req_compare(const void *a, const void *b) 1653 { 1654 return (((BlockRequest*) a)->sector - ((BlockRequest*) b)->sector); 1655 } 1656 1657 /* 1658 * Takes a bunch of requests and tries to merge them. Returns the number of 1659 * requests that remain after merging. 1660 */ 1661 static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, 1662 int num_reqs, MultiwriteCB *mcb) 1663 { 1664 int i, outidx; 1665 1666 // Sort requests by start sector 1667 qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare); 1668 1669 // Check if adjacent requests touch the same clusters. If so, combine them, 1670 // filling up gaps with zero sectors. 1671 outidx = 0; 1672 for (i = 1; i < num_reqs; i++) { 1673 int merge = 0; 1674 int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; 1675 1676 // This handles the cases that are valid for all block drivers, namely 1677 // exactly sequential writes and overlapping writes. 1678 if (reqs[i].sector <= oldreq_last) { 1679 merge = 1; 1680 } 1681 1682 // The block driver may decide that it makes sense to combine requests 1683 // even if there is a gap of some sectors between them. In this case, 1684 // the gap is filled with zeros (therefore only applicable for yet 1685 // unused space in format like qcow2). 1686 if (!merge && bs->drv->bdrv_merge_requests) { 1687 merge = bs->drv->bdrv_merge_requests(bs, &reqs[outidx], &reqs[i]); 1688 } 1689 1690 if (merge) { 1691 size_t size; 1692 QEMUIOVector *qiov = qemu_mallocz(sizeof(*qiov)); 1693 qemu_iovec_init(qiov, 1694 reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1); 1695 1696 // Add the first request to the merged one. If the requests are 1697 // overlapping, drop the last sectors of the first request. 1698 size = (reqs[i].sector - reqs[outidx].sector) << 9; 1699 qemu_iovec_concat(qiov, reqs[outidx].qiov, size); 1700 1701 // We might need to add some zeros between the two requests 1702 if (reqs[i].sector > oldreq_last) { 1703 size_t zero_bytes = (reqs[i].sector - oldreq_last) << 9; 1704 uint8_t *buf = qemu_blockalign(bs, zero_bytes); 1705 memset(buf, 0, zero_bytes); 1706 qemu_iovec_add(qiov, buf, zero_bytes); 1707 mcb->callbacks[i].free_buf = buf; 1708 } 1709 1710 // Add the second request 1711 qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size); 1712 1713 reqs[outidx].nb_sectors += reqs[i].nb_sectors; 1714 reqs[outidx].qiov = qiov; 1715 1716 mcb->callbacks[i].free_qiov = reqs[outidx].qiov; 1717 } else { 1718 outidx++; 1719 reqs[outidx].sector = reqs[i].sector; 1720 reqs[outidx].nb_sectors = reqs[i].nb_sectors; 1721 reqs[outidx].qiov = reqs[i].qiov; 1722 } 1723 } 1724 1725 return outidx + 1; 1726 } 1727 1728 /* 1729 * Submit multiple AIO write requests at once. 1730 * 1731 * On success, the function returns 0 and all requests in the reqs array have 1732 * been submitted. In error case this function returns -1, and any of the 1733 * requests may or may not be submitted yet. In particular, this means that the 1734 * callback will be called for some of the requests, for others it won't. The 1735 * caller must check the error field of the BlockRequest to wait for the right 1736 * callbacks (if error != 0, no callback will be called). 1737 * 1738 * The implementation may modify the contents of the reqs array, e.g. to merge 1739 * requests. However, the fields opaque and error are left unmodified as they 1740 * are used to signal failure for a single request to the caller. 1741 */ 1742 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) 1743 { 1744 BlockDriverAIOCB *acb; 1745 MultiwriteCB *mcb; 1746 int i; 1747 1748 if (num_reqs == 0) { 1749 return 0; 1750 } 1751 1752 // Create MultiwriteCB structure 1753 mcb = qemu_mallocz(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); 1754 mcb->num_requests = 0; 1755 mcb->num_callbacks = num_reqs; 1756 1757 for (i = 0; i < num_reqs; i++) { 1758 mcb->callbacks[i].cb = reqs[i].cb; 1759 mcb->callbacks[i].opaque = reqs[i].opaque; 1760 } 1761 1762 // Check for mergable requests 1763 num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); 1764 1765 // Run the aio requests 1766 for (i = 0; i < num_reqs; i++) { 1767 acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov, 1768 reqs[i].nb_sectors, multiwrite_cb, mcb); 1769 1770 if (acb == NULL) { 1771 // We can only fail the whole thing if no request has been 1772 // submitted yet. Otherwise we'll wait for the submitted AIOs to 1773 // complete and report the error in the callback. 1774 if (mcb->num_requests == 0) { 1775 reqs[i].error = EIO; 1776 goto fail; 1777 } else { 1778 mcb->error = EIO; 1779 break; 1780 } 1781 } else { 1782 mcb->num_requests++; 1783 } 1784 } 1785 1786 return 0; 1787 1788 fail: 1789 free(mcb); 1790 return -1; 1791 } 1792 1793 BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs, 1794 BlockDriverCompletionFunc *cb, void *opaque) 1795 { 1796 BlockDriver *drv = bs->drv; 1797 1798 if (!drv) 1799 return NULL; 1800 1801 /* 1802 * Note that unlike bdrv_flush the driver is reponsible for flushing a 1803 * backing image if it exists. 1804 */ 1805 return drv->bdrv_aio_flush(bs, cb, opaque); 1806 } 1807 1808 void bdrv_aio_cancel(BlockDriverAIOCB *acb) 1809 { 1810 acb->pool->cancel(acb); 1811 } 1812 1813 1814 /**************************************************************/ 1815 /* async block device emulation */ 1816 1817 typedef struct BlockDriverAIOCBSync { 1818 BlockDriverAIOCB common; 1819 QEMUBH *bh; 1820 int ret; 1821 /* vector translation state */ 1822 QEMUIOVector *qiov; 1823 uint8_t *bounce; 1824 int is_write; 1825 } BlockDriverAIOCBSync; 1826 1827 static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb) 1828 { 1829 BlockDriverAIOCBSync *acb = (BlockDriverAIOCBSync *)blockacb; 1830 qemu_bh_delete(acb->bh); 1831 acb->bh = NULL; 1832 qemu_aio_release(acb); 1833 } 1834 1835 static AIOPool bdrv_em_aio_pool = { 1836 .aiocb_size = sizeof(BlockDriverAIOCBSync), 1837 .cancel = bdrv_aio_cancel_em, 1838 }; 1839 1840 static void bdrv_aio_bh_cb(void *opaque) 1841 { 1842 BlockDriverAIOCBSync *acb = opaque; 1843 1844 if (!acb->is_write) 1845 qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size); 1846 qemu_vfree(acb->bounce); 1847 acb->common.cb(acb->common.opaque, acb->ret); 1848 qemu_bh_delete(acb->bh); 1849 acb->bh = NULL; 1850 qemu_aio_release(acb); 1851 } 1852 1853 static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs, 1854 int64_t sector_num, 1855 QEMUIOVector *qiov, 1856 int nb_sectors, 1857 BlockDriverCompletionFunc *cb, 1858 void *opaque, 1859 int is_write) 1860 1861 { 1862 BlockDriverAIOCBSync *acb; 1863 1864 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 1865 acb->is_write = is_write; 1866 acb->qiov = qiov; 1867 acb->bounce = qemu_blockalign(bs, qiov->size); 1868 1869 if (!acb->bh) 1870 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 1871 1872 if (is_write) { 1873 qemu_iovec_to_buffer(acb->qiov, acb->bounce); 1874 acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors); 1875 } else { 1876 acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors); 1877 } 1878 1879 qemu_bh_schedule(acb->bh); 1880 1881 return &acb->common; 1882 } 1883 1884 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 1885 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 1886 BlockDriverCompletionFunc *cb, void *opaque) 1887 { 1888 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); 1889 } 1890 1891 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 1892 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 1893 BlockDriverCompletionFunc *cb, void *opaque) 1894 { 1895 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); 1896 } 1897 1898 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs, 1899 BlockDriverCompletionFunc *cb, void *opaque) 1900 { 1901 BlockDriverAIOCBSync *acb; 1902 1903 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 1904 acb->is_write = 1; /* don't bounce in the completion hadler */ 1905 acb->qiov = NULL; 1906 acb->bounce = NULL; 1907 acb->ret = 0; 1908 1909 if (!acb->bh) 1910 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 1911 1912 bdrv_flush(bs); 1913 qemu_bh_schedule(acb->bh); 1914 return &acb->common; 1915 } 1916 1917 /**************************************************************/ 1918 /* sync block device emulation */ 1919 1920 static void bdrv_rw_em_cb(void *opaque, int ret) 1921 { 1922 *(int *)opaque = ret; 1923 } 1924 1925 #define NOT_DONE 0x7fffffff 1926 1927 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num, 1928 uint8_t *buf, int nb_sectors) 1929 { 1930 int async_ret; 1931 BlockDriverAIOCB *acb; 1932 struct iovec iov; 1933 QEMUIOVector qiov; 1934 1935 async_context_push(); 1936 1937 async_ret = NOT_DONE; 1938 iov.iov_base = (void *)buf; 1939 iov.iov_len = nb_sectors * 512; 1940 qemu_iovec_init_external(&qiov, &iov, 1); 1941 acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors, 1942 bdrv_rw_em_cb, &async_ret); 1943 if (acb == NULL) { 1944 async_ret = -1; 1945 goto fail; 1946 } 1947 1948 while (async_ret == NOT_DONE) { 1949 qemu_aio_wait(); 1950 } 1951 1952 1953 fail: 1954 async_context_pop(); 1955 return async_ret; 1956 } 1957 1958 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num, 1959 const uint8_t *buf, int nb_sectors) 1960 { 1961 int async_ret; 1962 BlockDriverAIOCB *acb; 1963 struct iovec iov; 1964 QEMUIOVector qiov; 1965 1966 async_context_push(); 1967 1968 async_ret = NOT_DONE; 1969 iov.iov_base = (void *)buf; 1970 iov.iov_len = nb_sectors * 512; 1971 qemu_iovec_init_external(&qiov, &iov, 1); 1972 acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors, 1973 bdrv_rw_em_cb, &async_ret); 1974 if (acb == NULL) { 1975 async_ret = -1; 1976 goto fail; 1977 } 1978 while (async_ret == NOT_DONE) { 1979 qemu_aio_wait(); 1980 } 1981 1982 fail: 1983 async_context_pop(); 1984 return async_ret; 1985 } 1986 1987 void bdrv_init(void) 1988 { 1989 module_call_init(MODULE_INIT_BLOCK); 1990 } 1991 1992 void bdrv_init_with_whitelist(void) 1993 { 1994 use_bdrv_whitelist = 1; 1995 bdrv_init(); 1996 } 1997 1998 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs, 1999 BlockDriverCompletionFunc *cb, void *opaque) 2000 { 2001 BlockDriverAIOCB *acb; 2002 2003 if (pool->free_aiocb) { 2004 acb = pool->free_aiocb; 2005 pool->free_aiocb = acb->next; 2006 } else { 2007 acb = qemu_mallocz(pool->aiocb_size); 2008 acb->pool = pool; 2009 } 2010 acb->bs = bs; 2011 acb->cb = cb; 2012 acb->opaque = opaque; 2013 return acb; 2014 } 2015 2016 void qemu_aio_release(void *p) 2017 { 2018 BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p; 2019 AIOPool *pool = acb->pool; 2020 acb->next = pool->free_aiocb; 2021 pool->free_aiocb = acb; 2022 } 2023 2024 /**************************************************************/ 2025 /* removable device support */ 2026 2027 /** 2028 * Return TRUE if the media is present 2029 */ 2030 int bdrv_is_inserted(BlockDriverState *bs) 2031 { 2032 BlockDriver *drv = bs->drv; 2033 int ret; 2034 if (!drv) 2035 return 0; 2036 if (!drv->bdrv_is_inserted) 2037 return 1; 2038 ret = drv->bdrv_is_inserted(bs); 2039 return ret; 2040 } 2041 2042 /** 2043 * Return TRUE if the media changed since the last call to this 2044 * function. It is currently only used for floppy disks 2045 */ 2046 int bdrv_media_changed(BlockDriverState *bs) 2047 { 2048 BlockDriver *drv = bs->drv; 2049 int ret; 2050 2051 if (!drv || !drv->bdrv_media_changed) 2052 ret = -ENOTSUP; 2053 else 2054 ret = drv->bdrv_media_changed(bs); 2055 if (ret == -ENOTSUP) 2056 ret = bs->media_changed; 2057 bs->media_changed = 0; 2058 return ret; 2059 } 2060 2061 /** 2062 * If eject_flag is TRUE, eject the media. Otherwise, close the tray 2063 */ 2064 int bdrv_eject(BlockDriverState *bs, int eject_flag) 2065 { 2066 BlockDriver *drv = bs->drv; 2067 int ret; 2068 2069 if (bs->locked) { 2070 return -EBUSY; 2071 } 2072 2073 if (!drv || !drv->bdrv_eject) { 2074 ret = -ENOTSUP; 2075 } else { 2076 ret = drv->bdrv_eject(bs, eject_flag); 2077 } 2078 if (ret == -ENOTSUP) { 2079 if (eject_flag) 2080 bdrv_close(bs); 2081 ret = 0; 2082 } 2083 2084 return ret; 2085 } 2086 2087 int bdrv_is_locked(BlockDriverState *bs) 2088 { 2089 return bs->locked; 2090 } 2091 2092 /** 2093 * Lock or unlock the media (if it is locked, the user won't be able 2094 * to eject it manually). 2095 */ 2096 void bdrv_set_locked(BlockDriverState *bs, int locked) 2097 { 2098 BlockDriver *drv = bs->drv; 2099 2100 bs->locked = locked; 2101 if (drv && drv->bdrv_set_locked) { 2102 drv->bdrv_set_locked(bs, locked); 2103 } 2104 } 2105 2106 /* needed for generic scsi interface */ 2107 2108 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) 2109 { 2110 BlockDriver *drv = bs->drv; 2111 2112 if (drv && drv->bdrv_ioctl) 2113 return drv->bdrv_ioctl(bs, req, buf); 2114 return -ENOTSUP; 2115 } 2116 2117 BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, 2118 unsigned long int req, void *buf, 2119 BlockDriverCompletionFunc *cb, void *opaque) 2120 { 2121 BlockDriver *drv = bs->drv; 2122 2123 if (drv && drv->bdrv_aio_ioctl) 2124 return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); 2125 return NULL; 2126 } 2127 2128 2129 2130 void *qemu_blockalign(BlockDriverState *bs, size_t size) 2131 { 2132 return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size); 2133 } 2134 2135 void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable) 2136 { 2137 int64_t bitmap_size; 2138 2139 if (enable) { 2140 if (!bs->dirty_bitmap) { 2141 bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) + 2142 BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1; 2143 bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8; 2144 2145 bs->dirty_bitmap = qemu_mallocz(bitmap_size); 2146 } 2147 } else { 2148 if (bs->dirty_bitmap) { 2149 qemu_free(bs->dirty_bitmap); 2150 bs->dirty_bitmap = NULL; 2151 } 2152 } 2153 } 2154 2155 int bdrv_get_dirty(BlockDriverState *bs, int64_t sector) 2156 { 2157 int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK; 2158 2159 if (bs->dirty_bitmap && 2160 (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) { 2161 return bs->dirty_bitmap[chunk / (sizeof(unsigned long) * 8)] & 2162 (1 << (chunk % (sizeof(unsigned long) * 8))); 2163 } else { 2164 return 0; 2165 } 2166 } 2167 2168 void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, 2169 int nr_sectors) 2170 { 2171 set_dirty_bitmap(bs, cur_sector, nr_sectors, 0); 2172 } 2173