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 "trace.h" 27 #include "monitor.h" 28 #include "block_int.h" 29 #include "module.h" 30 #include "qemu-objects.h" 31 32 #ifdef CONFIG_BSD 33 #include <sys/types.h> 34 #include <sys/stat.h> 35 #include <sys/ioctl.h> 36 #include <sys/queue.h> 37 #ifndef __DragonFly__ 38 #include <sys/disk.h> 39 #endif 40 #endif 41 42 #ifdef _WIN32 43 #include <windows.h> 44 #endif 45 46 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 47 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 48 BlockDriverCompletionFunc *cb, void *opaque); 49 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 50 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 51 BlockDriverCompletionFunc *cb, void *opaque); 52 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs, 53 BlockDriverCompletionFunc *cb, void *opaque); 54 static BlockDriverAIOCB *bdrv_aio_noop_em(BlockDriverState *bs, 55 BlockDriverCompletionFunc *cb, void *opaque); 56 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num, 57 uint8_t *buf, int nb_sectors); 58 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num, 59 const uint8_t *buf, int nb_sectors); 60 61 static QTAILQ_HEAD(, BlockDriverState) bdrv_states = 62 QTAILQ_HEAD_INITIALIZER(bdrv_states); 63 64 static QLIST_HEAD(, BlockDriver) bdrv_drivers = 65 QLIST_HEAD_INITIALIZER(bdrv_drivers); 66 67 /* The device to use for VM snapshots */ 68 static BlockDriverState *bs_snapshots; 69 70 /* If non-zero, use only whitelisted block drivers */ 71 static int use_bdrv_whitelist; 72 73 #ifdef _WIN32 74 static int is_windows_drive_prefix(const char *filename) 75 { 76 return (((filename[0] >= 'a' && filename[0] <= 'z') || 77 (filename[0] >= 'A' && filename[0] <= 'Z')) && 78 filename[1] == ':'); 79 } 80 81 int is_windows_drive(const char *filename) 82 { 83 if (is_windows_drive_prefix(filename) && 84 filename[2] == '\0') 85 return 1; 86 if (strstart(filename, "\\\\.\\", NULL) || 87 strstart(filename, "//./", NULL)) 88 return 1; 89 return 0; 90 } 91 #endif 92 93 /* check if the path starts with "<protocol>:" */ 94 static int path_has_protocol(const char *path) 95 { 96 #ifdef _WIN32 97 if (is_windows_drive(path) || 98 is_windows_drive_prefix(path)) { 99 return 0; 100 } 101 #endif 102 103 return strchr(path, ':') != NULL; 104 } 105 106 int path_is_absolute(const char *path) 107 { 108 const char *p; 109 #ifdef _WIN32 110 /* specific case for names like: "\\.\d:" */ 111 if (*path == '/' || *path == '\\') 112 return 1; 113 #endif 114 p = strchr(path, ':'); 115 if (p) 116 p++; 117 else 118 p = path; 119 #ifdef _WIN32 120 return (*p == '/' || *p == '\\'); 121 #else 122 return (*p == '/'); 123 #endif 124 } 125 126 /* if filename is absolute, just copy it to dest. Otherwise, build a 127 path to it by considering it is relative to base_path. URL are 128 supported. */ 129 void path_combine(char *dest, int dest_size, 130 const char *base_path, 131 const char *filename) 132 { 133 const char *p, *p1; 134 int len; 135 136 if (dest_size <= 0) 137 return; 138 if (path_is_absolute(filename)) { 139 pstrcpy(dest, dest_size, filename); 140 } else { 141 p = strchr(base_path, ':'); 142 if (p) 143 p++; 144 else 145 p = base_path; 146 p1 = strrchr(base_path, '/'); 147 #ifdef _WIN32 148 { 149 const char *p2; 150 p2 = strrchr(base_path, '\\'); 151 if (!p1 || p2 > p1) 152 p1 = p2; 153 } 154 #endif 155 if (p1) 156 p1++; 157 else 158 p1 = base_path; 159 if (p1 > p) 160 p = p1; 161 len = p - base_path; 162 if (len > dest_size - 1) 163 len = dest_size - 1; 164 memcpy(dest, base_path, len); 165 dest[len] = '\0'; 166 pstrcat(dest, dest_size, filename); 167 } 168 } 169 170 void bdrv_register(BlockDriver *bdrv) 171 { 172 if (!bdrv->bdrv_aio_readv) { 173 /* add AIO emulation layer */ 174 bdrv->bdrv_aio_readv = bdrv_aio_readv_em; 175 bdrv->bdrv_aio_writev = bdrv_aio_writev_em; 176 } else if (!bdrv->bdrv_read) { 177 /* add synchronous IO emulation layer */ 178 bdrv->bdrv_read = bdrv_read_em; 179 bdrv->bdrv_write = bdrv_write_em; 180 } 181 182 if (!bdrv->bdrv_aio_flush) 183 bdrv->bdrv_aio_flush = bdrv_aio_flush_em; 184 185 QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list); 186 } 187 188 /* create a new block device (by default it is empty) */ 189 BlockDriverState *bdrv_new(const char *device_name) 190 { 191 BlockDriverState *bs; 192 193 bs = qemu_mallocz(sizeof(BlockDriverState)); 194 pstrcpy(bs->device_name, sizeof(bs->device_name), device_name); 195 if (device_name[0] != '\0') { 196 QTAILQ_INSERT_TAIL(&bdrv_states, bs, list); 197 } 198 return bs; 199 } 200 201 BlockDriver *bdrv_find_format(const char *format_name) 202 { 203 BlockDriver *drv1; 204 QLIST_FOREACH(drv1, &bdrv_drivers, list) { 205 if (!strcmp(drv1->format_name, format_name)) { 206 return drv1; 207 } 208 } 209 return NULL; 210 } 211 212 static int bdrv_is_whitelisted(BlockDriver *drv) 213 { 214 static const char *whitelist[] = { 215 CONFIG_BDRV_WHITELIST 216 }; 217 const char **p; 218 219 if (!whitelist[0]) 220 return 1; /* no whitelist, anything goes */ 221 222 for (p = whitelist; *p; p++) { 223 if (!strcmp(drv->format_name, *p)) { 224 return 1; 225 } 226 } 227 return 0; 228 } 229 230 BlockDriver *bdrv_find_whitelisted_format(const char *format_name) 231 { 232 BlockDriver *drv = bdrv_find_format(format_name); 233 return drv && bdrv_is_whitelisted(drv) ? drv : NULL; 234 } 235 236 int bdrv_create(BlockDriver *drv, const char* filename, 237 QEMUOptionParameter *options) 238 { 239 if (!drv->bdrv_create) 240 return -ENOTSUP; 241 242 return drv->bdrv_create(filename, options); 243 } 244 245 int bdrv_create_file(const char* filename, QEMUOptionParameter *options) 246 { 247 BlockDriver *drv; 248 249 drv = bdrv_find_protocol(filename); 250 if (drv == NULL) { 251 return -ENOENT; 252 } 253 254 return bdrv_create(drv, filename, options); 255 } 256 257 #ifdef _WIN32 258 void get_tmp_filename(char *filename, int size) 259 { 260 char temp_dir[MAX_PATH]; 261 262 GetTempPath(MAX_PATH, temp_dir); 263 GetTempFileName(temp_dir, "qem", 0, filename); 264 } 265 #else 266 void get_tmp_filename(char *filename, int size) 267 { 268 int fd; 269 const char *tmpdir; 270 /* XXX: race condition possible */ 271 tmpdir = getenv("TMPDIR"); 272 if (!tmpdir) 273 tmpdir = "/tmp"; 274 snprintf(filename, size, "%s/vl.XXXXXX", tmpdir); 275 fd = mkstemp(filename); 276 close(fd); 277 } 278 #endif 279 280 /* 281 * Detect host devices. By convention, /dev/cdrom[N] is always 282 * recognized as a host CDROM. 283 */ 284 static BlockDriver *find_hdev_driver(const char *filename) 285 { 286 int score_max = 0, score; 287 BlockDriver *drv = NULL, *d; 288 289 QLIST_FOREACH(d, &bdrv_drivers, list) { 290 if (d->bdrv_probe_device) { 291 score = d->bdrv_probe_device(filename); 292 if (score > score_max) { 293 score_max = score; 294 drv = d; 295 } 296 } 297 } 298 299 return drv; 300 } 301 302 BlockDriver *bdrv_find_protocol(const char *filename) 303 { 304 BlockDriver *drv1; 305 char protocol[128]; 306 int len; 307 const char *p; 308 309 /* TODO Drivers without bdrv_file_open must be specified explicitly */ 310 311 /* 312 * XXX(hch): we really should not let host device detection 313 * override an explicit protocol specification, but moving this 314 * later breaks access to device names with colons in them. 315 * Thanks to the brain-dead persistent naming schemes on udev- 316 * based Linux systems those actually are quite common. 317 */ 318 drv1 = find_hdev_driver(filename); 319 if (drv1) { 320 return drv1; 321 } 322 323 if (!path_has_protocol(filename)) { 324 return bdrv_find_format("file"); 325 } 326 p = strchr(filename, ':'); 327 assert(p != NULL); 328 len = p - filename; 329 if (len > sizeof(protocol) - 1) 330 len = sizeof(protocol) - 1; 331 memcpy(protocol, filename, len); 332 protocol[len] = '\0'; 333 QLIST_FOREACH(drv1, &bdrv_drivers, list) { 334 if (drv1->protocol_name && 335 !strcmp(drv1->protocol_name, protocol)) { 336 return drv1; 337 } 338 } 339 return NULL; 340 } 341 342 static int find_image_format(const char *filename, BlockDriver **pdrv) 343 { 344 int ret, score, score_max; 345 BlockDriver *drv1, *drv; 346 uint8_t buf[2048]; 347 BlockDriverState *bs; 348 349 ret = bdrv_file_open(&bs, filename, 0); 350 if (ret < 0) { 351 *pdrv = NULL; 352 return ret; 353 } 354 355 /* Return the raw BlockDriver * to scsi-generic devices or empty drives */ 356 if (bs->sg || !bdrv_is_inserted(bs)) { 357 bdrv_delete(bs); 358 drv = bdrv_find_format("raw"); 359 if (!drv) { 360 ret = -ENOENT; 361 } 362 *pdrv = drv; 363 return ret; 364 } 365 366 ret = bdrv_pread(bs, 0, buf, sizeof(buf)); 367 bdrv_delete(bs); 368 if (ret < 0) { 369 *pdrv = NULL; 370 return ret; 371 } 372 373 score_max = 0; 374 drv = NULL; 375 QLIST_FOREACH(drv1, &bdrv_drivers, list) { 376 if (drv1->bdrv_probe) { 377 score = drv1->bdrv_probe(buf, ret, filename); 378 if (score > score_max) { 379 score_max = score; 380 drv = drv1; 381 } 382 } 383 } 384 if (!drv) { 385 ret = -ENOENT; 386 } 387 *pdrv = drv; 388 return ret; 389 } 390 391 /** 392 * Set the current 'total_sectors' value 393 */ 394 static int refresh_total_sectors(BlockDriverState *bs, int64_t hint) 395 { 396 BlockDriver *drv = bs->drv; 397 398 /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */ 399 if (bs->sg) 400 return 0; 401 402 /* query actual device if possible, otherwise just trust the hint */ 403 if (drv->bdrv_getlength) { 404 int64_t length = drv->bdrv_getlength(bs); 405 if (length < 0) { 406 return length; 407 } 408 hint = length >> BDRV_SECTOR_BITS; 409 } 410 411 bs->total_sectors = hint; 412 return 0; 413 } 414 415 /* 416 * Common part for opening disk images and files 417 */ 418 static int bdrv_open_common(BlockDriverState *bs, const char *filename, 419 int flags, BlockDriver *drv) 420 { 421 int ret, open_flags; 422 423 assert(drv != NULL); 424 425 bs->file = NULL; 426 bs->total_sectors = 0; 427 bs->encrypted = 0; 428 bs->valid_key = 0; 429 bs->open_flags = flags; 430 /* buffer_alignment defaulted to 512, drivers can change this value */ 431 bs->buffer_alignment = 512; 432 433 pstrcpy(bs->filename, sizeof(bs->filename), filename); 434 435 if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) { 436 return -ENOTSUP; 437 } 438 439 bs->drv = drv; 440 bs->opaque = qemu_mallocz(drv->instance_size); 441 442 if (flags & BDRV_O_CACHE_WB) 443 bs->enable_write_cache = 1; 444 445 /* 446 * Clear flags that are internal to the block layer before opening the 447 * image. 448 */ 449 open_flags = flags & ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); 450 451 /* 452 * Snapshots should be writable. 453 */ 454 if (bs->is_temporary) { 455 open_flags |= BDRV_O_RDWR; 456 } 457 458 /* Open the image, either directly or using a protocol */ 459 if (drv->bdrv_file_open) { 460 ret = drv->bdrv_file_open(bs, filename, open_flags); 461 } else { 462 ret = bdrv_file_open(&bs->file, filename, open_flags); 463 if (ret >= 0) { 464 ret = drv->bdrv_open(bs, open_flags); 465 } 466 } 467 468 if (ret < 0) { 469 goto free_and_fail; 470 } 471 472 bs->keep_read_only = bs->read_only = !(open_flags & BDRV_O_RDWR); 473 474 ret = refresh_total_sectors(bs, bs->total_sectors); 475 if (ret < 0) { 476 goto free_and_fail; 477 } 478 479 #ifndef _WIN32 480 if (bs->is_temporary) { 481 unlink(filename); 482 } 483 #endif 484 return 0; 485 486 free_and_fail: 487 if (bs->file) { 488 bdrv_delete(bs->file); 489 bs->file = NULL; 490 } 491 qemu_free(bs->opaque); 492 bs->opaque = NULL; 493 bs->drv = NULL; 494 return ret; 495 } 496 497 /* 498 * Opens a file using a protocol (file, host_device, nbd, ...) 499 */ 500 int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags) 501 { 502 BlockDriverState *bs; 503 BlockDriver *drv; 504 int ret; 505 506 drv = bdrv_find_protocol(filename); 507 if (!drv) { 508 return -ENOENT; 509 } 510 511 bs = bdrv_new(""); 512 ret = bdrv_open_common(bs, filename, flags, drv); 513 if (ret < 0) { 514 bdrv_delete(bs); 515 return ret; 516 } 517 bs->growable = 1; 518 *pbs = bs; 519 return 0; 520 } 521 522 /* 523 * Opens a disk image (raw, qcow2, vmdk, ...) 524 */ 525 int bdrv_open(BlockDriverState *bs, const char *filename, int flags, 526 BlockDriver *drv) 527 { 528 int ret; 529 530 if (flags & BDRV_O_SNAPSHOT) { 531 BlockDriverState *bs1; 532 int64_t total_size; 533 int is_protocol = 0; 534 BlockDriver *bdrv_qcow2; 535 QEMUOptionParameter *options; 536 char tmp_filename[PATH_MAX]; 537 char backing_filename[PATH_MAX]; 538 539 /* if snapshot, we create a temporary backing file and open it 540 instead of opening 'filename' directly */ 541 542 /* if there is a backing file, use it */ 543 bs1 = bdrv_new(""); 544 ret = bdrv_open(bs1, filename, 0, drv); 545 if (ret < 0) { 546 bdrv_delete(bs1); 547 return ret; 548 } 549 total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK; 550 551 if (bs1->drv && bs1->drv->protocol_name) 552 is_protocol = 1; 553 554 bdrv_delete(bs1); 555 556 get_tmp_filename(tmp_filename, sizeof(tmp_filename)); 557 558 /* Real path is meaningless for protocols */ 559 if (is_protocol) 560 snprintf(backing_filename, sizeof(backing_filename), 561 "%s", filename); 562 else if (!realpath(filename, backing_filename)) 563 return -errno; 564 565 bdrv_qcow2 = bdrv_find_format("qcow2"); 566 options = parse_option_parameters("", bdrv_qcow2->create_options, NULL); 567 568 set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size); 569 set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename); 570 if (drv) { 571 set_option_parameter(options, BLOCK_OPT_BACKING_FMT, 572 drv->format_name); 573 } 574 575 ret = bdrv_create(bdrv_qcow2, tmp_filename, options); 576 free_option_parameters(options); 577 if (ret < 0) { 578 return ret; 579 } 580 581 filename = tmp_filename; 582 drv = bdrv_qcow2; 583 bs->is_temporary = 1; 584 } 585 586 /* Find the right image format driver */ 587 if (!drv) { 588 ret = find_image_format(filename, &drv); 589 } 590 591 if (!drv) { 592 goto unlink_and_fail; 593 } 594 595 /* Open the image */ 596 ret = bdrv_open_common(bs, filename, flags, drv); 597 if (ret < 0) { 598 goto unlink_and_fail; 599 } 600 601 /* If there is a backing file, use it */ 602 if ((flags & BDRV_O_NO_BACKING) == 0 && bs->backing_file[0] != '\0') { 603 char backing_filename[PATH_MAX]; 604 int back_flags; 605 BlockDriver *back_drv = NULL; 606 607 bs->backing_hd = bdrv_new(""); 608 609 if (path_has_protocol(bs->backing_file)) { 610 pstrcpy(backing_filename, sizeof(backing_filename), 611 bs->backing_file); 612 } else { 613 path_combine(backing_filename, sizeof(backing_filename), 614 filename, bs->backing_file); 615 } 616 617 if (bs->backing_format[0] != '\0') { 618 back_drv = bdrv_find_format(bs->backing_format); 619 } 620 621 /* backing files always opened read-only */ 622 back_flags = 623 flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); 624 625 ret = bdrv_open(bs->backing_hd, backing_filename, back_flags, back_drv); 626 if (ret < 0) { 627 bdrv_close(bs); 628 return ret; 629 } 630 if (bs->is_temporary) { 631 bs->backing_hd->keep_read_only = !(flags & BDRV_O_RDWR); 632 } else { 633 /* base image inherits from "parent" */ 634 bs->backing_hd->keep_read_only = bs->keep_read_only; 635 } 636 } 637 638 if (!bdrv_key_required(bs)) { 639 /* call the change callback */ 640 bs->media_changed = 1; 641 if (bs->change_cb) 642 bs->change_cb(bs->change_opaque, CHANGE_MEDIA); 643 } 644 645 return 0; 646 647 unlink_and_fail: 648 if (bs->is_temporary) { 649 unlink(filename); 650 } 651 return ret; 652 } 653 654 void bdrv_close(BlockDriverState *bs) 655 { 656 if (bs->drv) { 657 if (bs == bs_snapshots) { 658 bs_snapshots = NULL; 659 } 660 if (bs->backing_hd) { 661 bdrv_delete(bs->backing_hd); 662 bs->backing_hd = NULL; 663 } 664 bs->drv->bdrv_close(bs); 665 qemu_free(bs->opaque); 666 #ifdef _WIN32 667 if (bs->is_temporary) { 668 unlink(bs->filename); 669 } 670 #endif 671 bs->opaque = NULL; 672 bs->drv = NULL; 673 674 if (bs->file != NULL) { 675 bdrv_close(bs->file); 676 } 677 678 /* call the change callback */ 679 bs->media_changed = 1; 680 if (bs->change_cb) 681 bs->change_cb(bs->change_opaque, CHANGE_MEDIA); 682 } 683 } 684 685 void bdrv_close_all(void) 686 { 687 BlockDriverState *bs; 688 689 QTAILQ_FOREACH(bs, &bdrv_states, list) { 690 bdrv_close(bs); 691 } 692 } 693 694 /* make a BlockDriverState anonymous by removing from bdrv_state list. 695 Also, NULL terminate the device_name to prevent double remove */ 696 void bdrv_make_anon(BlockDriverState *bs) 697 { 698 if (bs->device_name[0] != '\0') { 699 QTAILQ_REMOVE(&bdrv_states, bs, list); 700 } 701 bs->device_name[0] = '\0'; 702 } 703 704 void bdrv_delete(BlockDriverState *bs) 705 { 706 assert(!bs->peer); 707 708 /* remove from list, if necessary */ 709 bdrv_make_anon(bs); 710 711 bdrv_close(bs); 712 if (bs->file != NULL) { 713 bdrv_delete(bs->file); 714 } 715 716 assert(bs != bs_snapshots); 717 qemu_free(bs); 718 } 719 720 int bdrv_attach(BlockDriverState *bs, DeviceState *qdev) 721 { 722 if (bs->peer) { 723 return -EBUSY; 724 } 725 bs->peer = qdev; 726 return 0; 727 } 728 729 void bdrv_detach(BlockDriverState *bs, DeviceState *qdev) 730 { 731 assert(bs->peer == qdev); 732 bs->peer = NULL; 733 } 734 735 DeviceState *bdrv_get_attached(BlockDriverState *bs) 736 { 737 return bs->peer; 738 } 739 740 /* 741 * Run consistency checks on an image 742 * 743 * Returns 0 if the check could be completed (it doesn't mean that the image is 744 * free of errors) or -errno when an internal error occurred. The results of the 745 * check are stored in res. 746 */ 747 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res) 748 { 749 if (bs->drv->bdrv_check == NULL) { 750 return -ENOTSUP; 751 } 752 753 memset(res, 0, sizeof(*res)); 754 return bs->drv->bdrv_check(bs, res); 755 } 756 757 #define COMMIT_BUF_SECTORS 2048 758 759 /* commit COW file into the raw image */ 760 int bdrv_commit(BlockDriverState *bs) 761 { 762 BlockDriver *drv = bs->drv; 763 BlockDriver *backing_drv; 764 int64_t sector, total_sectors; 765 int n, ro, open_flags; 766 int ret = 0, rw_ret = 0; 767 uint8_t *buf; 768 char filename[1024]; 769 BlockDriverState *bs_rw, *bs_ro; 770 771 if (!drv) 772 return -ENOMEDIUM; 773 774 if (!bs->backing_hd) { 775 return -ENOTSUP; 776 } 777 778 if (bs->backing_hd->keep_read_only) { 779 return -EACCES; 780 } 781 782 backing_drv = bs->backing_hd->drv; 783 ro = bs->backing_hd->read_only; 784 strncpy(filename, bs->backing_hd->filename, sizeof(filename)); 785 open_flags = bs->backing_hd->open_flags; 786 787 if (ro) { 788 /* re-open as RW */ 789 bdrv_delete(bs->backing_hd); 790 bs->backing_hd = NULL; 791 bs_rw = bdrv_new(""); 792 rw_ret = bdrv_open(bs_rw, filename, open_flags | BDRV_O_RDWR, 793 backing_drv); 794 if (rw_ret < 0) { 795 bdrv_delete(bs_rw); 796 /* try to re-open read-only */ 797 bs_ro = bdrv_new(""); 798 ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR, 799 backing_drv); 800 if (ret < 0) { 801 bdrv_delete(bs_ro); 802 /* drive not functional anymore */ 803 bs->drv = NULL; 804 return ret; 805 } 806 bs->backing_hd = bs_ro; 807 return rw_ret; 808 } 809 bs->backing_hd = bs_rw; 810 } 811 812 total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; 813 buf = qemu_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE); 814 815 for (sector = 0; sector < total_sectors; sector += n) { 816 if (drv->bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n)) { 817 818 if (bdrv_read(bs, sector, buf, n) != 0) { 819 ret = -EIO; 820 goto ro_cleanup; 821 } 822 823 if (bdrv_write(bs->backing_hd, sector, buf, n) != 0) { 824 ret = -EIO; 825 goto ro_cleanup; 826 } 827 } 828 } 829 830 if (drv->bdrv_make_empty) { 831 ret = drv->bdrv_make_empty(bs); 832 bdrv_flush(bs); 833 } 834 835 /* 836 * Make sure all data we wrote to the backing device is actually 837 * stable on disk. 838 */ 839 if (bs->backing_hd) 840 bdrv_flush(bs->backing_hd); 841 842 ro_cleanup: 843 qemu_free(buf); 844 845 if (ro) { 846 /* re-open as RO */ 847 bdrv_delete(bs->backing_hd); 848 bs->backing_hd = NULL; 849 bs_ro = bdrv_new(""); 850 ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR, 851 backing_drv); 852 if (ret < 0) { 853 bdrv_delete(bs_ro); 854 /* drive not functional anymore */ 855 bs->drv = NULL; 856 return ret; 857 } 858 bs->backing_hd = bs_ro; 859 bs->backing_hd->keep_read_only = 0; 860 } 861 862 return ret; 863 } 864 865 void bdrv_commit_all(void) 866 { 867 BlockDriverState *bs; 868 869 QTAILQ_FOREACH(bs, &bdrv_states, list) { 870 bdrv_commit(bs); 871 } 872 } 873 874 /* 875 * Return values: 876 * 0 - success 877 * -EINVAL - backing format specified, but no file 878 * -ENOSPC - can't update the backing file because no space is left in the 879 * image file header 880 * -ENOTSUP - format driver doesn't support changing the backing file 881 */ 882 int bdrv_change_backing_file(BlockDriverState *bs, 883 const char *backing_file, const char *backing_fmt) 884 { 885 BlockDriver *drv = bs->drv; 886 887 if (drv->bdrv_change_backing_file != NULL) { 888 return drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); 889 } else { 890 return -ENOTSUP; 891 } 892 } 893 894 static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 895 size_t size) 896 { 897 int64_t len; 898 899 if (!bdrv_is_inserted(bs)) 900 return -ENOMEDIUM; 901 902 if (bs->growable) 903 return 0; 904 905 len = bdrv_getlength(bs); 906 907 if (offset < 0) 908 return -EIO; 909 910 if ((offset > len) || (len - offset < size)) 911 return -EIO; 912 913 return 0; 914 } 915 916 static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, 917 int nb_sectors) 918 { 919 return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE, 920 nb_sectors * BDRV_SECTOR_SIZE); 921 } 922 923 /* return < 0 if error. See bdrv_write() for the return codes */ 924 int bdrv_read(BlockDriverState *bs, int64_t sector_num, 925 uint8_t *buf, int nb_sectors) 926 { 927 BlockDriver *drv = bs->drv; 928 929 if (!drv) 930 return -ENOMEDIUM; 931 if (bdrv_check_request(bs, sector_num, nb_sectors)) 932 return -EIO; 933 934 return drv->bdrv_read(bs, sector_num, buf, nb_sectors); 935 } 936 937 static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num, 938 int nb_sectors, int dirty) 939 { 940 int64_t start, end; 941 unsigned long val, idx, bit; 942 943 start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK; 944 end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK; 945 946 for (; start <= end; start++) { 947 idx = start / (sizeof(unsigned long) * 8); 948 bit = start % (sizeof(unsigned long) * 8); 949 val = bs->dirty_bitmap[idx]; 950 if (dirty) { 951 if (!(val & (1UL << bit))) { 952 bs->dirty_count++; 953 val |= 1UL << bit; 954 } 955 } else { 956 if (val & (1UL << bit)) { 957 bs->dirty_count--; 958 val &= ~(1UL << bit); 959 } 960 } 961 bs->dirty_bitmap[idx] = val; 962 } 963 } 964 965 /* Return < 0 if error. Important errors are: 966 -EIO generic I/O error (may happen for all errors) 967 -ENOMEDIUM No media inserted. 968 -EINVAL Invalid sector number or nb_sectors 969 -EACCES Trying to write a read-only device 970 */ 971 int bdrv_write(BlockDriverState *bs, int64_t sector_num, 972 const uint8_t *buf, int nb_sectors) 973 { 974 BlockDriver *drv = bs->drv; 975 if (!bs->drv) 976 return -ENOMEDIUM; 977 if (bs->read_only) 978 return -EACCES; 979 if (bdrv_check_request(bs, sector_num, nb_sectors)) 980 return -EIO; 981 982 if (bs->dirty_bitmap) { 983 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 984 } 985 986 if (bs->wr_highest_sector < sector_num + nb_sectors - 1) { 987 bs->wr_highest_sector = sector_num + nb_sectors - 1; 988 } 989 990 return drv->bdrv_write(bs, sector_num, buf, nb_sectors); 991 } 992 993 int bdrv_pread(BlockDriverState *bs, int64_t offset, 994 void *buf, int count1) 995 { 996 uint8_t tmp_buf[BDRV_SECTOR_SIZE]; 997 int len, nb_sectors, count; 998 int64_t sector_num; 999 int ret; 1000 1001 count = count1; 1002 /* first read to align to sector start */ 1003 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); 1004 if (len > count) 1005 len = count; 1006 sector_num = offset >> BDRV_SECTOR_BITS; 1007 if (len > 0) { 1008 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 1009 return ret; 1010 memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len); 1011 count -= len; 1012 if (count == 0) 1013 return count1; 1014 sector_num++; 1015 buf += len; 1016 } 1017 1018 /* read the sectors "in place" */ 1019 nb_sectors = count >> BDRV_SECTOR_BITS; 1020 if (nb_sectors > 0) { 1021 if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0) 1022 return ret; 1023 sector_num += nb_sectors; 1024 len = nb_sectors << BDRV_SECTOR_BITS; 1025 buf += len; 1026 count -= len; 1027 } 1028 1029 /* add data from the last sector */ 1030 if (count > 0) { 1031 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 1032 return ret; 1033 memcpy(buf, tmp_buf, count); 1034 } 1035 return count1; 1036 } 1037 1038 int bdrv_pwrite(BlockDriverState *bs, int64_t offset, 1039 const void *buf, int count1) 1040 { 1041 uint8_t tmp_buf[BDRV_SECTOR_SIZE]; 1042 int len, nb_sectors, count; 1043 int64_t sector_num; 1044 int ret; 1045 1046 count = count1; 1047 /* first write to align to sector start */ 1048 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); 1049 if (len > count) 1050 len = count; 1051 sector_num = offset >> BDRV_SECTOR_BITS; 1052 if (len > 0) { 1053 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 1054 return ret; 1055 memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len); 1056 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0) 1057 return ret; 1058 count -= len; 1059 if (count == 0) 1060 return count1; 1061 sector_num++; 1062 buf += len; 1063 } 1064 1065 /* write the sectors "in place" */ 1066 nb_sectors = count >> BDRV_SECTOR_BITS; 1067 if (nb_sectors > 0) { 1068 if ((ret = bdrv_write(bs, sector_num, buf, nb_sectors)) < 0) 1069 return ret; 1070 sector_num += nb_sectors; 1071 len = nb_sectors << BDRV_SECTOR_BITS; 1072 buf += len; 1073 count -= len; 1074 } 1075 1076 /* add data from the last sector */ 1077 if (count > 0) { 1078 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) 1079 return ret; 1080 memcpy(tmp_buf, buf, count); 1081 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0) 1082 return ret; 1083 } 1084 return count1; 1085 } 1086 1087 /* 1088 * Writes to the file and ensures that no writes are reordered across this 1089 * request (acts as a barrier) 1090 * 1091 * Returns 0 on success, -errno in error cases. 1092 */ 1093 int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset, 1094 const void *buf, int count) 1095 { 1096 int ret; 1097 1098 ret = bdrv_pwrite(bs, offset, buf, count); 1099 if (ret < 0) { 1100 return ret; 1101 } 1102 1103 /* No flush needed for cache=writethrough, it uses O_DSYNC */ 1104 if ((bs->open_flags & BDRV_O_CACHE_MASK) != 0) { 1105 bdrv_flush(bs); 1106 } 1107 1108 return 0; 1109 } 1110 1111 /* 1112 * Writes to the file and ensures that no writes are reordered across this 1113 * request (acts as a barrier) 1114 * 1115 * Returns 0 on success, -errno in error cases. 1116 */ 1117 int bdrv_write_sync(BlockDriverState *bs, int64_t sector_num, 1118 const uint8_t *buf, int nb_sectors) 1119 { 1120 return bdrv_pwrite_sync(bs, BDRV_SECTOR_SIZE * sector_num, 1121 buf, BDRV_SECTOR_SIZE * nb_sectors); 1122 } 1123 1124 /** 1125 * Truncate file to 'offset' bytes (needed only for file protocols) 1126 */ 1127 int bdrv_truncate(BlockDriverState *bs, int64_t offset) 1128 { 1129 BlockDriver *drv = bs->drv; 1130 int ret; 1131 if (!drv) 1132 return -ENOMEDIUM; 1133 if (!drv->bdrv_truncate) 1134 return -ENOTSUP; 1135 if (bs->read_only) 1136 return -EACCES; 1137 if (bdrv_in_use(bs)) 1138 return -EBUSY; 1139 ret = drv->bdrv_truncate(bs, offset); 1140 if (ret == 0) { 1141 ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS); 1142 if (bs->change_cb) { 1143 bs->change_cb(bs->change_opaque, CHANGE_SIZE); 1144 } 1145 } 1146 return ret; 1147 } 1148 1149 /** 1150 * Length of a file in bytes. Return < 0 if error or unknown. 1151 */ 1152 int64_t bdrv_getlength(BlockDriverState *bs) 1153 { 1154 BlockDriver *drv = bs->drv; 1155 if (!drv) 1156 return -ENOMEDIUM; 1157 1158 if (bs->growable || bs->removable) { 1159 if (drv->bdrv_getlength) { 1160 return drv->bdrv_getlength(bs); 1161 } 1162 } 1163 return bs->total_sectors * BDRV_SECTOR_SIZE; 1164 } 1165 1166 /* return 0 as number of sectors if no device present or error */ 1167 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr) 1168 { 1169 int64_t length; 1170 length = bdrv_getlength(bs); 1171 if (length < 0) 1172 length = 0; 1173 else 1174 length = length >> BDRV_SECTOR_BITS; 1175 *nb_sectors_ptr = length; 1176 } 1177 1178 struct partition { 1179 uint8_t boot_ind; /* 0x80 - active */ 1180 uint8_t head; /* starting head */ 1181 uint8_t sector; /* starting sector */ 1182 uint8_t cyl; /* starting cylinder */ 1183 uint8_t sys_ind; /* What partition type */ 1184 uint8_t end_head; /* end head */ 1185 uint8_t end_sector; /* end sector */ 1186 uint8_t end_cyl; /* end cylinder */ 1187 uint32_t start_sect; /* starting sector counting from 0 */ 1188 uint32_t nr_sects; /* nr of sectors in partition */ 1189 } __attribute__((packed)); 1190 1191 /* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */ 1192 static int guess_disk_lchs(BlockDriverState *bs, 1193 int *pcylinders, int *pheads, int *psectors) 1194 { 1195 uint8_t buf[BDRV_SECTOR_SIZE]; 1196 int ret, i, heads, sectors, cylinders; 1197 struct partition *p; 1198 uint32_t nr_sects; 1199 uint64_t nb_sectors; 1200 1201 bdrv_get_geometry(bs, &nb_sectors); 1202 1203 ret = bdrv_read(bs, 0, buf, 1); 1204 if (ret < 0) 1205 return -1; 1206 /* test msdos magic */ 1207 if (buf[510] != 0x55 || buf[511] != 0xaa) 1208 return -1; 1209 for(i = 0; i < 4; i++) { 1210 p = ((struct partition *)(buf + 0x1be)) + i; 1211 nr_sects = le32_to_cpu(p->nr_sects); 1212 if (nr_sects && p->end_head) { 1213 /* We make the assumption that the partition terminates on 1214 a cylinder boundary */ 1215 heads = p->end_head + 1; 1216 sectors = p->end_sector & 63; 1217 if (sectors == 0) 1218 continue; 1219 cylinders = nb_sectors / (heads * sectors); 1220 if (cylinders < 1 || cylinders > 16383) 1221 continue; 1222 *pheads = heads; 1223 *psectors = sectors; 1224 *pcylinders = cylinders; 1225 #if 0 1226 printf("guessed geometry: LCHS=%d %d %d\n", 1227 cylinders, heads, sectors); 1228 #endif 1229 return 0; 1230 } 1231 } 1232 return -1; 1233 } 1234 1235 void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs) 1236 { 1237 int translation, lba_detected = 0; 1238 int cylinders, heads, secs; 1239 uint64_t nb_sectors; 1240 1241 /* if a geometry hint is available, use it */ 1242 bdrv_get_geometry(bs, &nb_sectors); 1243 bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs); 1244 translation = bdrv_get_translation_hint(bs); 1245 if (cylinders != 0) { 1246 *pcyls = cylinders; 1247 *pheads = heads; 1248 *psecs = secs; 1249 } else { 1250 if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) { 1251 if (heads > 16) { 1252 /* if heads > 16, it means that a BIOS LBA 1253 translation was active, so the default 1254 hardware geometry is OK */ 1255 lba_detected = 1; 1256 goto default_geometry; 1257 } else { 1258 *pcyls = cylinders; 1259 *pheads = heads; 1260 *psecs = secs; 1261 /* disable any translation to be in sync with 1262 the logical geometry */ 1263 if (translation == BIOS_ATA_TRANSLATION_AUTO) { 1264 bdrv_set_translation_hint(bs, 1265 BIOS_ATA_TRANSLATION_NONE); 1266 } 1267 } 1268 } else { 1269 default_geometry: 1270 /* if no geometry, use a standard physical disk geometry */ 1271 cylinders = nb_sectors / (16 * 63); 1272 1273 if (cylinders > 16383) 1274 cylinders = 16383; 1275 else if (cylinders < 2) 1276 cylinders = 2; 1277 *pcyls = cylinders; 1278 *pheads = 16; 1279 *psecs = 63; 1280 if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) { 1281 if ((*pcyls * *pheads) <= 131072) { 1282 bdrv_set_translation_hint(bs, 1283 BIOS_ATA_TRANSLATION_LARGE); 1284 } else { 1285 bdrv_set_translation_hint(bs, 1286 BIOS_ATA_TRANSLATION_LBA); 1287 } 1288 } 1289 } 1290 bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs); 1291 } 1292 } 1293 1294 void bdrv_set_geometry_hint(BlockDriverState *bs, 1295 int cyls, int heads, int secs) 1296 { 1297 bs->cyls = cyls; 1298 bs->heads = heads; 1299 bs->secs = secs; 1300 } 1301 1302 void bdrv_set_translation_hint(BlockDriverState *bs, int translation) 1303 { 1304 bs->translation = translation; 1305 } 1306 1307 void bdrv_get_geometry_hint(BlockDriverState *bs, 1308 int *pcyls, int *pheads, int *psecs) 1309 { 1310 *pcyls = bs->cyls; 1311 *pheads = bs->heads; 1312 *psecs = bs->secs; 1313 } 1314 1315 /* Recognize floppy formats */ 1316 typedef struct FDFormat { 1317 FDriveType drive; 1318 uint8_t last_sect; 1319 uint8_t max_track; 1320 uint8_t max_head; 1321 } FDFormat; 1322 1323 static const FDFormat fd_formats[] = { 1324 /* First entry is default format */ 1325 /* 1.44 MB 3"1/2 floppy disks */ 1326 { FDRIVE_DRV_144, 18, 80, 1, }, 1327 { FDRIVE_DRV_144, 20, 80, 1, }, 1328 { FDRIVE_DRV_144, 21, 80, 1, }, 1329 { FDRIVE_DRV_144, 21, 82, 1, }, 1330 { FDRIVE_DRV_144, 21, 83, 1, }, 1331 { FDRIVE_DRV_144, 22, 80, 1, }, 1332 { FDRIVE_DRV_144, 23, 80, 1, }, 1333 { FDRIVE_DRV_144, 24, 80, 1, }, 1334 /* 2.88 MB 3"1/2 floppy disks */ 1335 { FDRIVE_DRV_288, 36, 80, 1, }, 1336 { FDRIVE_DRV_288, 39, 80, 1, }, 1337 { FDRIVE_DRV_288, 40, 80, 1, }, 1338 { FDRIVE_DRV_288, 44, 80, 1, }, 1339 { FDRIVE_DRV_288, 48, 80, 1, }, 1340 /* 720 kB 3"1/2 floppy disks */ 1341 { FDRIVE_DRV_144, 9, 80, 1, }, 1342 { FDRIVE_DRV_144, 10, 80, 1, }, 1343 { FDRIVE_DRV_144, 10, 82, 1, }, 1344 { FDRIVE_DRV_144, 10, 83, 1, }, 1345 { FDRIVE_DRV_144, 13, 80, 1, }, 1346 { FDRIVE_DRV_144, 14, 80, 1, }, 1347 /* 1.2 MB 5"1/4 floppy disks */ 1348 { FDRIVE_DRV_120, 15, 80, 1, }, 1349 { FDRIVE_DRV_120, 18, 80, 1, }, 1350 { FDRIVE_DRV_120, 18, 82, 1, }, 1351 { FDRIVE_DRV_120, 18, 83, 1, }, 1352 { FDRIVE_DRV_120, 20, 80, 1, }, 1353 /* 720 kB 5"1/4 floppy disks */ 1354 { FDRIVE_DRV_120, 9, 80, 1, }, 1355 { FDRIVE_DRV_120, 11, 80, 1, }, 1356 /* 360 kB 5"1/4 floppy disks */ 1357 { FDRIVE_DRV_120, 9, 40, 1, }, 1358 { FDRIVE_DRV_120, 9, 40, 0, }, 1359 { FDRIVE_DRV_120, 10, 41, 1, }, 1360 { FDRIVE_DRV_120, 10, 42, 1, }, 1361 /* 320 kB 5"1/4 floppy disks */ 1362 { FDRIVE_DRV_120, 8, 40, 1, }, 1363 { FDRIVE_DRV_120, 8, 40, 0, }, 1364 /* 360 kB must match 5"1/4 better than 3"1/2... */ 1365 { FDRIVE_DRV_144, 9, 80, 0, }, 1366 /* end */ 1367 { FDRIVE_DRV_NONE, -1, -1, 0, }, 1368 }; 1369 1370 void bdrv_get_floppy_geometry_hint(BlockDriverState *bs, int *nb_heads, 1371 int *max_track, int *last_sect, 1372 FDriveType drive_in, FDriveType *drive) 1373 { 1374 const FDFormat *parse; 1375 uint64_t nb_sectors, size; 1376 int i, first_match, match; 1377 1378 bdrv_get_geometry_hint(bs, nb_heads, max_track, last_sect); 1379 if (*nb_heads != 0 && *max_track != 0 && *last_sect != 0) { 1380 /* User defined disk */ 1381 } else { 1382 bdrv_get_geometry(bs, &nb_sectors); 1383 match = -1; 1384 first_match = -1; 1385 for (i = 0; ; i++) { 1386 parse = &fd_formats[i]; 1387 if (parse->drive == FDRIVE_DRV_NONE) { 1388 break; 1389 } 1390 if (drive_in == parse->drive || 1391 drive_in == FDRIVE_DRV_NONE) { 1392 size = (parse->max_head + 1) * parse->max_track * 1393 parse->last_sect; 1394 if (nb_sectors == size) { 1395 match = i; 1396 break; 1397 } 1398 if (first_match == -1) { 1399 first_match = i; 1400 } 1401 } 1402 } 1403 if (match == -1) { 1404 if (first_match == -1) { 1405 match = 1; 1406 } else { 1407 match = first_match; 1408 } 1409 parse = &fd_formats[match]; 1410 } 1411 *nb_heads = parse->max_head + 1; 1412 *max_track = parse->max_track; 1413 *last_sect = parse->last_sect; 1414 *drive = parse->drive; 1415 } 1416 } 1417 1418 int bdrv_get_translation_hint(BlockDriverState *bs) 1419 { 1420 return bs->translation; 1421 } 1422 1423 void bdrv_set_on_error(BlockDriverState *bs, BlockErrorAction on_read_error, 1424 BlockErrorAction on_write_error) 1425 { 1426 bs->on_read_error = on_read_error; 1427 bs->on_write_error = on_write_error; 1428 } 1429 1430 BlockErrorAction bdrv_get_on_error(BlockDriverState *bs, int is_read) 1431 { 1432 return is_read ? bs->on_read_error : bs->on_write_error; 1433 } 1434 1435 void bdrv_set_removable(BlockDriverState *bs, int removable) 1436 { 1437 bs->removable = removable; 1438 if (removable && bs == bs_snapshots) { 1439 bs_snapshots = NULL; 1440 } 1441 } 1442 1443 int bdrv_is_removable(BlockDriverState *bs) 1444 { 1445 return bs->removable; 1446 } 1447 1448 int bdrv_is_read_only(BlockDriverState *bs) 1449 { 1450 return bs->read_only; 1451 } 1452 1453 int bdrv_is_sg(BlockDriverState *bs) 1454 { 1455 return bs->sg; 1456 } 1457 1458 int bdrv_enable_write_cache(BlockDriverState *bs) 1459 { 1460 return bs->enable_write_cache; 1461 } 1462 1463 /* XXX: no longer used */ 1464 void bdrv_set_change_cb(BlockDriverState *bs, 1465 void (*change_cb)(void *opaque, int reason), 1466 void *opaque) 1467 { 1468 bs->change_cb = change_cb; 1469 bs->change_opaque = opaque; 1470 } 1471 1472 int bdrv_is_encrypted(BlockDriverState *bs) 1473 { 1474 if (bs->backing_hd && bs->backing_hd->encrypted) 1475 return 1; 1476 return bs->encrypted; 1477 } 1478 1479 int bdrv_key_required(BlockDriverState *bs) 1480 { 1481 BlockDriverState *backing_hd = bs->backing_hd; 1482 1483 if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key) 1484 return 1; 1485 return (bs->encrypted && !bs->valid_key); 1486 } 1487 1488 int bdrv_set_key(BlockDriverState *bs, const char *key) 1489 { 1490 int ret; 1491 if (bs->backing_hd && bs->backing_hd->encrypted) { 1492 ret = bdrv_set_key(bs->backing_hd, key); 1493 if (ret < 0) 1494 return ret; 1495 if (!bs->encrypted) 1496 return 0; 1497 } 1498 if (!bs->encrypted) { 1499 return -EINVAL; 1500 } else if (!bs->drv || !bs->drv->bdrv_set_key) { 1501 return -ENOMEDIUM; 1502 } 1503 ret = bs->drv->bdrv_set_key(bs, key); 1504 if (ret < 0) { 1505 bs->valid_key = 0; 1506 } else if (!bs->valid_key) { 1507 bs->valid_key = 1; 1508 /* call the change callback now, we skipped it on open */ 1509 bs->media_changed = 1; 1510 if (bs->change_cb) 1511 bs->change_cb(bs->change_opaque, CHANGE_MEDIA); 1512 } 1513 return ret; 1514 } 1515 1516 void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size) 1517 { 1518 if (!bs->drv) { 1519 buf[0] = '\0'; 1520 } else { 1521 pstrcpy(buf, buf_size, bs->drv->format_name); 1522 } 1523 } 1524 1525 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 1526 void *opaque) 1527 { 1528 BlockDriver *drv; 1529 1530 QLIST_FOREACH(drv, &bdrv_drivers, list) { 1531 it(opaque, drv->format_name); 1532 } 1533 } 1534 1535 BlockDriverState *bdrv_find(const char *name) 1536 { 1537 BlockDriverState *bs; 1538 1539 QTAILQ_FOREACH(bs, &bdrv_states, list) { 1540 if (!strcmp(name, bs->device_name)) { 1541 return bs; 1542 } 1543 } 1544 return NULL; 1545 } 1546 1547 BlockDriverState *bdrv_next(BlockDriverState *bs) 1548 { 1549 if (!bs) { 1550 return QTAILQ_FIRST(&bdrv_states); 1551 } 1552 return QTAILQ_NEXT(bs, list); 1553 } 1554 1555 void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque) 1556 { 1557 BlockDriverState *bs; 1558 1559 QTAILQ_FOREACH(bs, &bdrv_states, list) { 1560 it(opaque, bs); 1561 } 1562 } 1563 1564 const char *bdrv_get_device_name(BlockDriverState *bs) 1565 { 1566 return bs->device_name; 1567 } 1568 1569 int bdrv_flush(BlockDriverState *bs) 1570 { 1571 if (bs->open_flags & BDRV_O_NO_FLUSH) { 1572 return 0; 1573 } 1574 1575 if (bs->drv && bs->drv->bdrv_flush) { 1576 return bs->drv->bdrv_flush(bs); 1577 } 1578 1579 /* 1580 * Some block drivers always operate in either writethrough or unsafe mode 1581 * and don't support bdrv_flush therefore. Usually qemu doesn't know how 1582 * the server works (because the behaviour is hardcoded or depends on 1583 * server-side configuration), so we can't ensure that everything is safe 1584 * on disk. Returning an error doesn't work because that would break guests 1585 * even if the server operates in writethrough mode. 1586 * 1587 * Let's hope the user knows what he's doing. 1588 */ 1589 return 0; 1590 } 1591 1592 void bdrv_flush_all(void) 1593 { 1594 BlockDriverState *bs; 1595 1596 QTAILQ_FOREACH(bs, &bdrv_states, list) { 1597 if (bs->drv && !bdrv_is_read_only(bs) && 1598 (!bdrv_is_removable(bs) || bdrv_is_inserted(bs))) { 1599 bdrv_flush(bs); 1600 } 1601 } 1602 } 1603 1604 int bdrv_has_zero_init(BlockDriverState *bs) 1605 { 1606 assert(bs->drv); 1607 1608 if (bs->drv->bdrv_has_zero_init) { 1609 return bs->drv->bdrv_has_zero_init(bs); 1610 } 1611 1612 return 1; 1613 } 1614 1615 int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) 1616 { 1617 if (!bs->drv) { 1618 return -ENOMEDIUM; 1619 } 1620 if (!bs->drv->bdrv_discard) { 1621 return 0; 1622 } 1623 return bs->drv->bdrv_discard(bs, sector_num, nb_sectors); 1624 } 1625 1626 /* 1627 * Returns true iff the specified sector is present in the disk image. Drivers 1628 * not implementing the functionality are assumed to not support backing files, 1629 * hence all their sectors are reported as allocated. 1630 * 1631 * 'pnum' is set to the number of sectors (including and immediately following 1632 * the specified sector) that are known to be in the same 1633 * allocated/unallocated state. 1634 * 1635 * 'nb_sectors' is the max value 'pnum' should be set to. 1636 */ 1637 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, 1638 int *pnum) 1639 { 1640 int64_t n; 1641 if (!bs->drv->bdrv_is_allocated) { 1642 if (sector_num >= bs->total_sectors) { 1643 *pnum = 0; 1644 return 0; 1645 } 1646 n = bs->total_sectors - sector_num; 1647 *pnum = (n < nb_sectors) ? (n) : (nb_sectors); 1648 return 1; 1649 } 1650 return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum); 1651 } 1652 1653 void bdrv_mon_event(const BlockDriverState *bdrv, 1654 BlockMonEventAction action, int is_read) 1655 { 1656 QObject *data; 1657 const char *action_str; 1658 1659 switch (action) { 1660 case BDRV_ACTION_REPORT: 1661 action_str = "report"; 1662 break; 1663 case BDRV_ACTION_IGNORE: 1664 action_str = "ignore"; 1665 break; 1666 case BDRV_ACTION_STOP: 1667 action_str = "stop"; 1668 break; 1669 default: 1670 abort(); 1671 } 1672 1673 data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }", 1674 bdrv->device_name, 1675 action_str, 1676 is_read ? "read" : "write"); 1677 monitor_protocol_event(QEVENT_BLOCK_IO_ERROR, data); 1678 1679 qobject_decref(data); 1680 } 1681 1682 static void bdrv_print_dict(QObject *obj, void *opaque) 1683 { 1684 QDict *bs_dict; 1685 Monitor *mon = opaque; 1686 1687 bs_dict = qobject_to_qdict(obj); 1688 1689 monitor_printf(mon, "%s: removable=%d", 1690 qdict_get_str(bs_dict, "device"), 1691 qdict_get_bool(bs_dict, "removable")); 1692 1693 if (qdict_get_bool(bs_dict, "removable")) { 1694 monitor_printf(mon, " locked=%d", qdict_get_bool(bs_dict, "locked")); 1695 } 1696 1697 if (qdict_haskey(bs_dict, "inserted")) { 1698 QDict *qdict = qobject_to_qdict(qdict_get(bs_dict, "inserted")); 1699 1700 monitor_printf(mon, " file="); 1701 monitor_print_filename(mon, qdict_get_str(qdict, "file")); 1702 if (qdict_haskey(qdict, "backing_file")) { 1703 monitor_printf(mon, " backing_file="); 1704 monitor_print_filename(mon, qdict_get_str(qdict, "backing_file")); 1705 } 1706 monitor_printf(mon, " ro=%d drv=%s encrypted=%d", 1707 qdict_get_bool(qdict, "ro"), 1708 qdict_get_str(qdict, "drv"), 1709 qdict_get_bool(qdict, "encrypted")); 1710 } else { 1711 monitor_printf(mon, " [not inserted]"); 1712 } 1713 1714 monitor_printf(mon, "\n"); 1715 } 1716 1717 void bdrv_info_print(Monitor *mon, const QObject *data) 1718 { 1719 qlist_iter(qobject_to_qlist(data), bdrv_print_dict, mon); 1720 } 1721 1722 void bdrv_info(Monitor *mon, QObject **ret_data) 1723 { 1724 QList *bs_list; 1725 BlockDriverState *bs; 1726 1727 bs_list = qlist_new(); 1728 1729 QTAILQ_FOREACH(bs, &bdrv_states, list) { 1730 QObject *bs_obj; 1731 1732 bs_obj = qobject_from_jsonf("{ 'device': %s, 'type': 'unknown', " 1733 "'removable': %i, 'locked': %i }", 1734 bs->device_name, bs->removable, 1735 bs->locked); 1736 1737 if (bs->drv) { 1738 QObject *obj; 1739 QDict *bs_dict = qobject_to_qdict(bs_obj); 1740 1741 obj = qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, " 1742 "'encrypted': %i }", 1743 bs->filename, bs->read_only, 1744 bs->drv->format_name, 1745 bdrv_is_encrypted(bs)); 1746 if (bs->backing_file[0] != '\0') { 1747 QDict *qdict = qobject_to_qdict(obj); 1748 qdict_put(qdict, "backing_file", 1749 qstring_from_str(bs->backing_file)); 1750 } 1751 1752 qdict_put_obj(bs_dict, "inserted", obj); 1753 } 1754 qlist_append_obj(bs_list, bs_obj); 1755 } 1756 1757 *ret_data = QOBJECT(bs_list); 1758 } 1759 1760 static void bdrv_stats_iter(QObject *data, void *opaque) 1761 { 1762 QDict *qdict; 1763 Monitor *mon = opaque; 1764 1765 qdict = qobject_to_qdict(data); 1766 monitor_printf(mon, "%s:", qdict_get_str(qdict, "device")); 1767 1768 qdict = qobject_to_qdict(qdict_get(qdict, "stats")); 1769 monitor_printf(mon, " rd_bytes=%" PRId64 1770 " wr_bytes=%" PRId64 1771 " rd_operations=%" PRId64 1772 " wr_operations=%" PRId64 1773 "\n", 1774 qdict_get_int(qdict, "rd_bytes"), 1775 qdict_get_int(qdict, "wr_bytes"), 1776 qdict_get_int(qdict, "rd_operations"), 1777 qdict_get_int(qdict, "wr_operations")); 1778 } 1779 1780 void bdrv_stats_print(Monitor *mon, const QObject *data) 1781 { 1782 qlist_iter(qobject_to_qlist(data), bdrv_stats_iter, mon); 1783 } 1784 1785 static QObject* bdrv_info_stats_bs(BlockDriverState *bs) 1786 { 1787 QObject *res; 1788 QDict *dict; 1789 1790 res = qobject_from_jsonf("{ 'stats': {" 1791 "'rd_bytes': %" PRId64 "," 1792 "'wr_bytes': %" PRId64 "," 1793 "'rd_operations': %" PRId64 "," 1794 "'wr_operations': %" PRId64 "," 1795 "'wr_highest_offset': %" PRId64 1796 "} }", 1797 bs->rd_bytes, bs->wr_bytes, 1798 bs->rd_ops, bs->wr_ops, 1799 bs->wr_highest_sector * 1800 (uint64_t)BDRV_SECTOR_SIZE); 1801 dict = qobject_to_qdict(res); 1802 1803 if (*bs->device_name) { 1804 qdict_put(dict, "device", qstring_from_str(bs->device_name)); 1805 } 1806 1807 if (bs->file) { 1808 QObject *parent = bdrv_info_stats_bs(bs->file); 1809 qdict_put_obj(dict, "parent", parent); 1810 } 1811 1812 return res; 1813 } 1814 1815 void bdrv_info_stats(Monitor *mon, QObject **ret_data) 1816 { 1817 QObject *obj; 1818 QList *devices; 1819 BlockDriverState *bs; 1820 1821 devices = qlist_new(); 1822 1823 QTAILQ_FOREACH(bs, &bdrv_states, list) { 1824 obj = bdrv_info_stats_bs(bs); 1825 qlist_append_obj(devices, obj); 1826 } 1827 1828 *ret_data = QOBJECT(devices); 1829 } 1830 1831 const char *bdrv_get_encrypted_filename(BlockDriverState *bs) 1832 { 1833 if (bs->backing_hd && bs->backing_hd->encrypted) 1834 return bs->backing_file; 1835 else if (bs->encrypted) 1836 return bs->filename; 1837 else 1838 return NULL; 1839 } 1840 1841 void bdrv_get_backing_filename(BlockDriverState *bs, 1842 char *filename, int filename_size) 1843 { 1844 if (!bs->backing_file) { 1845 pstrcpy(filename, filename_size, ""); 1846 } else { 1847 pstrcpy(filename, filename_size, bs->backing_file); 1848 } 1849 } 1850 1851 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num, 1852 const uint8_t *buf, int nb_sectors) 1853 { 1854 BlockDriver *drv = bs->drv; 1855 if (!drv) 1856 return -ENOMEDIUM; 1857 if (!drv->bdrv_write_compressed) 1858 return -ENOTSUP; 1859 if (bdrv_check_request(bs, sector_num, nb_sectors)) 1860 return -EIO; 1861 1862 if (bs->dirty_bitmap) { 1863 set_dirty_bitmap(bs, sector_num, nb_sectors, 1); 1864 } 1865 1866 return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors); 1867 } 1868 1869 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1870 { 1871 BlockDriver *drv = bs->drv; 1872 if (!drv) 1873 return -ENOMEDIUM; 1874 if (!drv->bdrv_get_info) 1875 return -ENOTSUP; 1876 memset(bdi, 0, sizeof(*bdi)); 1877 return drv->bdrv_get_info(bs, bdi); 1878 } 1879 1880 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 1881 int64_t pos, int size) 1882 { 1883 BlockDriver *drv = bs->drv; 1884 if (!drv) 1885 return -ENOMEDIUM; 1886 if (drv->bdrv_save_vmstate) 1887 return drv->bdrv_save_vmstate(bs, buf, pos, size); 1888 if (bs->file) 1889 return bdrv_save_vmstate(bs->file, buf, pos, size); 1890 return -ENOTSUP; 1891 } 1892 1893 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 1894 int64_t pos, int size) 1895 { 1896 BlockDriver *drv = bs->drv; 1897 if (!drv) 1898 return -ENOMEDIUM; 1899 if (drv->bdrv_load_vmstate) 1900 return drv->bdrv_load_vmstate(bs, buf, pos, size); 1901 if (bs->file) 1902 return bdrv_load_vmstate(bs->file, buf, pos, size); 1903 return -ENOTSUP; 1904 } 1905 1906 void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event) 1907 { 1908 BlockDriver *drv = bs->drv; 1909 1910 if (!drv || !drv->bdrv_debug_event) { 1911 return; 1912 } 1913 1914 return drv->bdrv_debug_event(bs, event); 1915 1916 } 1917 1918 /**************************************************************/ 1919 /* handling of snapshots */ 1920 1921 int bdrv_can_snapshot(BlockDriverState *bs) 1922 { 1923 BlockDriver *drv = bs->drv; 1924 if (!drv || bdrv_is_removable(bs) || bdrv_is_read_only(bs)) { 1925 return 0; 1926 } 1927 1928 if (!drv->bdrv_snapshot_create) { 1929 if (bs->file != NULL) { 1930 return bdrv_can_snapshot(bs->file); 1931 } 1932 return 0; 1933 } 1934 1935 return 1; 1936 } 1937 1938 int bdrv_is_snapshot(BlockDriverState *bs) 1939 { 1940 return !!(bs->open_flags & BDRV_O_SNAPSHOT); 1941 } 1942 1943 BlockDriverState *bdrv_snapshots(void) 1944 { 1945 BlockDriverState *bs; 1946 1947 if (bs_snapshots) { 1948 return bs_snapshots; 1949 } 1950 1951 bs = NULL; 1952 while ((bs = bdrv_next(bs))) { 1953 if (bdrv_can_snapshot(bs)) { 1954 bs_snapshots = bs; 1955 return bs; 1956 } 1957 } 1958 return NULL; 1959 } 1960 1961 int bdrv_snapshot_create(BlockDriverState *bs, 1962 QEMUSnapshotInfo *sn_info) 1963 { 1964 BlockDriver *drv = bs->drv; 1965 if (!drv) 1966 return -ENOMEDIUM; 1967 if (drv->bdrv_snapshot_create) 1968 return drv->bdrv_snapshot_create(bs, sn_info); 1969 if (bs->file) 1970 return bdrv_snapshot_create(bs->file, sn_info); 1971 return -ENOTSUP; 1972 } 1973 1974 int bdrv_snapshot_goto(BlockDriverState *bs, 1975 const char *snapshot_id) 1976 { 1977 BlockDriver *drv = bs->drv; 1978 int ret, open_ret; 1979 1980 if (!drv) 1981 return -ENOMEDIUM; 1982 if (drv->bdrv_snapshot_goto) 1983 return drv->bdrv_snapshot_goto(bs, snapshot_id); 1984 1985 if (bs->file) { 1986 drv->bdrv_close(bs); 1987 ret = bdrv_snapshot_goto(bs->file, snapshot_id); 1988 open_ret = drv->bdrv_open(bs, bs->open_flags); 1989 if (open_ret < 0) { 1990 bdrv_delete(bs->file); 1991 bs->drv = NULL; 1992 return open_ret; 1993 } 1994 return ret; 1995 } 1996 1997 return -ENOTSUP; 1998 } 1999 2000 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) 2001 { 2002 BlockDriver *drv = bs->drv; 2003 if (!drv) 2004 return -ENOMEDIUM; 2005 if (drv->bdrv_snapshot_delete) 2006 return drv->bdrv_snapshot_delete(bs, snapshot_id); 2007 if (bs->file) 2008 return bdrv_snapshot_delete(bs->file, snapshot_id); 2009 return -ENOTSUP; 2010 } 2011 2012 int bdrv_snapshot_list(BlockDriverState *bs, 2013 QEMUSnapshotInfo **psn_info) 2014 { 2015 BlockDriver *drv = bs->drv; 2016 if (!drv) 2017 return -ENOMEDIUM; 2018 if (drv->bdrv_snapshot_list) 2019 return drv->bdrv_snapshot_list(bs, psn_info); 2020 if (bs->file) 2021 return bdrv_snapshot_list(bs->file, psn_info); 2022 return -ENOTSUP; 2023 } 2024 2025 int bdrv_snapshot_load_tmp(BlockDriverState *bs, 2026 const char *snapshot_name) 2027 { 2028 BlockDriver *drv = bs->drv; 2029 if (!drv) { 2030 return -ENOMEDIUM; 2031 } 2032 if (!bs->read_only) { 2033 return -EINVAL; 2034 } 2035 if (drv->bdrv_snapshot_load_tmp) { 2036 return drv->bdrv_snapshot_load_tmp(bs, snapshot_name); 2037 } 2038 return -ENOTSUP; 2039 } 2040 2041 #define NB_SUFFIXES 4 2042 2043 char *get_human_readable_size(char *buf, int buf_size, int64_t size) 2044 { 2045 static const char suffixes[NB_SUFFIXES] = "KMGT"; 2046 int64_t base; 2047 int i; 2048 2049 if (size <= 999) { 2050 snprintf(buf, buf_size, "%" PRId64, size); 2051 } else { 2052 base = 1024; 2053 for(i = 0; i < NB_SUFFIXES; i++) { 2054 if (size < (10 * base)) { 2055 snprintf(buf, buf_size, "%0.1f%c", 2056 (double)size / base, 2057 suffixes[i]); 2058 break; 2059 } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) { 2060 snprintf(buf, buf_size, "%" PRId64 "%c", 2061 ((size + (base >> 1)) / base), 2062 suffixes[i]); 2063 break; 2064 } 2065 base = base * 1024; 2066 } 2067 } 2068 return buf; 2069 } 2070 2071 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn) 2072 { 2073 char buf1[128], date_buf[128], clock_buf[128]; 2074 #ifdef _WIN32 2075 struct tm *ptm; 2076 #else 2077 struct tm tm; 2078 #endif 2079 time_t ti; 2080 int64_t secs; 2081 2082 if (!sn) { 2083 snprintf(buf, buf_size, 2084 "%-10s%-20s%7s%20s%15s", 2085 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK"); 2086 } else { 2087 ti = sn->date_sec; 2088 #ifdef _WIN32 2089 ptm = localtime(&ti); 2090 strftime(date_buf, sizeof(date_buf), 2091 "%Y-%m-%d %H:%M:%S", ptm); 2092 #else 2093 localtime_r(&ti, &tm); 2094 strftime(date_buf, sizeof(date_buf), 2095 "%Y-%m-%d %H:%M:%S", &tm); 2096 #endif 2097 secs = sn->vm_clock_nsec / 1000000000; 2098 snprintf(clock_buf, sizeof(clock_buf), 2099 "%02d:%02d:%02d.%03d", 2100 (int)(secs / 3600), 2101 (int)((secs / 60) % 60), 2102 (int)(secs % 60), 2103 (int)((sn->vm_clock_nsec / 1000000) % 1000)); 2104 snprintf(buf, buf_size, 2105 "%-10s%-20s%7s%20s%15s", 2106 sn->id_str, sn->name, 2107 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size), 2108 date_buf, 2109 clock_buf); 2110 } 2111 return buf; 2112 } 2113 2114 2115 /**************************************************************/ 2116 /* async I/Os */ 2117 2118 BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, 2119 QEMUIOVector *qiov, int nb_sectors, 2120 BlockDriverCompletionFunc *cb, void *opaque) 2121 { 2122 BlockDriver *drv = bs->drv; 2123 BlockDriverAIOCB *ret; 2124 2125 trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque); 2126 2127 if (!drv) 2128 return NULL; 2129 if (bdrv_check_request(bs, sector_num, nb_sectors)) 2130 return NULL; 2131 2132 ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, 2133 cb, opaque); 2134 2135 if (ret) { 2136 /* Update stats even though technically transfer has not happened. */ 2137 bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE; 2138 bs->rd_ops ++; 2139 } 2140 2141 return ret; 2142 } 2143 2144 typedef struct BlockCompleteData { 2145 BlockDriverCompletionFunc *cb; 2146 void *opaque; 2147 BlockDriverState *bs; 2148 int64_t sector_num; 2149 int nb_sectors; 2150 } BlockCompleteData; 2151 2152 static void block_complete_cb(void *opaque, int ret) 2153 { 2154 BlockCompleteData *b = opaque; 2155 2156 if (b->bs->dirty_bitmap) { 2157 set_dirty_bitmap(b->bs, b->sector_num, b->nb_sectors, 1); 2158 } 2159 b->cb(b->opaque, ret); 2160 qemu_free(b); 2161 } 2162 2163 static BlockCompleteData *blk_dirty_cb_alloc(BlockDriverState *bs, 2164 int64_t sector_num, 2165 int nb_sectors, 2166 BlockDriverCompletionFunc *cb, 2167 void *opaque) 2168 { 2169 BlockCompleteData *blkdata = qemu_mallocz(sizeof(BlockCompleteData)); 2170 2171 blkdata->bs = bs; 2172 blkdata->cb = cb; 2173 blkdata->opaque = opaque; 2174 blkdata->sector_num = sector_num; 2175 blkdata->nb_sectors = nb_sectors; 2176 2177 return blkdata; 2178 } 2179 2180 BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, 2181 QEMUIOVector *qiov, int nb_sectors, 2182 BlockDriverCompletionFunc *cb, void *opaque) 2183 { 2184 BlockDriver *drv = bs->drv; 2185 BlockDriverAIOCB *ret; 2186 BlockCompleteData *blk_cb_data; 2187 2188 trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque); 2189 2190 if (!drv) 2191 return NULL; 2192 if (bs->read_only) 2193 return NULL; 2194 if (bdrv_check_request(bs, sector_num, nb_sectors)) 2195 return NULL; 2196 2197 if (bs->dirty_bitmap) { 2198 blk_cb_data = blk_dirty_cb_alloc(bs, sector_num, nb_sectors, cb, 2199 opaque); 2200 cb = &block_complete_cb; 2201 opaque = blk_cb_data; 2202 } 2203 2204 ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, 2205 cb, opaque); 2206 2207 if (ret) { 2208 /* Update stats even though technically transfer has not happened. */ 2209 bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE; 2210 bs->wr_ops ++; 2211 if (bs->wr_highest_sector < sector_num + nb_sectors - 1) { 2212 bs->wr_highest_sector = sector_num + nb_sectors - 1; 2213 } 2214 } 2215 2216 return ret; 2217 } 2218 2219 2220 typedef struct MultiwriteCB { 2221 int error; 2222 int num_requests; 2223 int num_callbacks; 2224 struct { 2225 BlockDriverCompletionFunc *cb; 2226 void *opaque; 2227 QEMUIOVector *free_qiov; 2228 void *free_buf; 2229 } callbacks[]; 2230 } MultiwriteCB; 2231 2232 static void multiwrite_user_cb(MultiwriteCB *mcb) 2233 { 2234 int i; 2235 2236 for (i = 0; i < mcb->num_callbacks; i++) { 2237 mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); 2238 if (mcb->callbacks[i].free_qiov) { 2239 qemu_iovec_destroy(mcb->callbacks[i].free_qiov); 2240 } 2241 qemu_free(mcb->callbacks[i].free_qiov); 2242 qemu_vfree(mcb->callbacks[i].free_buf); 2243 } 2244 } 2245 2246 static void multiwrite_cb(void *opaque, int ret) 2247 { 2248 MultiwriteCB *mcb = opaque; 2249 2250 trace_multiwrite_cb(mcb, ret); 2251 2252 if (ret < 0 && !mcb->error) { 2253 mcb->error = ret; 2254 } 2255 2256 mcb->num_requests--; 2257 if (mcb->num_requests == 0) { 2258 multiwrite_user_cb(mcb); 2259 qemu_free(mcb); 2260 } 2261 } 2262 2263 static int multiwrite_req_compare(const void *a, const void *b) 2264 { 2265 const BlockRequest *req1 = a, *req2 = b; 2266 2267 /* 2268 * Note that we can't simply subtract req2->sector from req1->sector 2269 * here as that could overflow the return value. 2270 */ 2271 if (req1->sector > req2->sector) { 2272 return 1; 2273 } else if (req1->sector < req2->sector) { 2274 return -1; 2275 } else { 2276 return 0; 2277 } 2278 } 2279 2280 /* 2281 * Takes a bunch of requests and tries to merge them. Returns the number of 2282 * requests that remain after merging. 2283 */ 2284 static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, 2285 int num_reqs, MultiwriteCB *mcb) 2286 { 2287 int i, outidx; 2288 2289 // Sort requests by start sector 2290 qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare); 2291 2292 // Check if adjacent requests touch the same clusters. If so, combine them, 2293 // filling up gaps with zero sectors. 2294 outidx = 0; 2295 for (i = 1; i < num_reqs; i++) { 2296 int merge = 0; 2297 int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; 2298 2299 // This handles the cases that are valid for all block drivers, namely 2300 // exactly sequential writes and overlapping writes. 2301 if (reqs[i].sector <= oldreq_last) { 2302 merge = 1; 2303 } 2304 2305 // The block driver may decide that it makes sense to combine requests 2306 // even if there is a gap of some sectors between them. In this case, 2307 // the gap is filled with zeros (therefore only applicable for yet 2308 // unused space in format like qcow2). 2309 if (!merge && bs->drv->bdrv_merge_requests) { 2310 merge = bs->drv->bdrv_merge_requests(bs, &reqs[outidx], &reqs[i]); 2311 } 2312 2313 if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) { 2314 merge = 0; 2315 } 2316 2317 if (merge) { 2318 size_t size; 2319 QEMUIOVector *qiov = qemu_mallocz(sizeof(*qiov)); 2320 qemu_iovec_init(qiov, 2321 reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1); 2322 2323 // Add the first request to the merged one. If the requests are 2324 // overlapping, drop the last sectors of the first request. 2325 size = (reqs[i].sector - reqs[outidx].sector) << 9; 2326 qemu_iovec_concat(qiov, reqs[outidx].qiov, size); 2327 2328 // We might need to add some zeros between the two requests 2329 if (reqs[i].sector > oldreq_last) { 2330 size_t zero_bytes = (reqs[i].sector - oldreq_last) << 9; 2331 uint8_t *buf = qemu_blockalign(bs, zero_bytes); 2332 memset(buf, 0, zero_bytes); 2333 qemu_iovec_add(qiov, buf, zero_bytes); 2334 mcb->callbacks[i].free_buf = buf; 2335 } 2336 2337 // Add the second request 2338 qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size); 2339 2340 reqs[outidx].nb_sectors = qiov->size >> 9; 2341 reqs[outidx].qiov = qiov; 2342 2343 mcb->callbacks[i].free_qiov = reqs[outidx].qiov; 2344 } else { 2345 outidx++; 2346 reqs[outidx].sector = reqs[i].sector; 2347 reqs[outidx].nb_sectors = reqs[i].nb_sectors; 2348 reqs[outidx].qiov = reqs[i].qiov; 2349 } 2350 } 2351 2352 return outidx + 1; 2353 } 2354 2355 /* 2356 * Submit multiple AIO write requests at once. 2357 * 2358 * On success, the function returns 0 and all requests in the reqs array have 2359 * been submitted. In error case this function returns -1, and any of the 2360 * requests may or may not be submitted yet. In particular, this means that the 2361 * callback will be called for some of the requests, for others it won't. The 2362 * caller must check the error field of the BlockRequest to wait for the right 2363 * callbacks (if error != 0, no callback will be called). 2364 * 2365 * The implementation may modify the contents of the reqs array, e.g. to merge 2366 * requests. However, the fields opaque and error are left unmodified as they 2367 * are used to signal failure for a single request to the caller. 2368 */ 2369 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) 2370 { 2371 BlockDriverAIOCB *acb; 2372 MultiwriteCB *mcb; 2373 int i; 2374 2375 /* don't submit writes if we don't have a medium */ 2376 if (bs->drv == NULL) { 2377 for (i = 0; i < num_reqs; i++) { 2378 reqs[i].error = -ENOMEDIUM; 2379 } 2380 return -1; 2381 } 2382 2383 if (num_reqs == 0) { 2384 return 0; 2385 } 2386 2387 // Create MultiwriteCB structure 2388 mcb = qemu_mallocz(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); 2389 mcb->num_requests = 0; 2390 mcb->num_callbacks = num_reqs; 2391 2392 for (i = 0; i < num_reqs; i++) { 2393 mcb->callbacks[i].cb = reqs[i].cb; 2394 mcb->callbacks[i].opaque = reqs[i].opaque; 2395 } 2396 2397 // Check for mergable requests 2398 num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); 2399 2400 trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs); 2401 2402 /* 2403 * Run the aio requests. As soon as one request can't be submitted 2404 * successfully, fail all requests that are not yet submitted (we must 2405 * return failure for all requests anyway) 2406 * 2407 * num_requests cannot be set to the right value immediately: If 2408 * bdrv_aio_writev fails for some request, num_requests would be too high 2409 * and therefore multiwrite_cb() would never recognize the multiwrite 2410 * request as completed. We also cannot use the loop variable i to set it 2411 * when the first request fails because the callback may already have been 2412 * called for previously submitted requests. Thus, num_requests must be 2413 * incremented for each request that is submitted. 2414 * 2415 * The problem that callbacks may be called early also means that we need 2416 * to take care that num_requests doesn't become 0 before all requests are 2417 * submitted - multiwrite_cb() would consider the multiwrite request 2418 * completed. A dummy request that is "completed" by a manual call to 2419 * multiwrite_cb() takes care of this. 2420 */ 2421 mcb->num_requests = 1; 2422 2423 // Run the aio requests 2424 for (i = 0; i < num_reqs; i++) { 2425 mcb->num_requests++; 2426 acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov, 2427 reqs[i].nb_sectors, multiwrite_cb, mcb); 2428 2429 if (acb == NULL) { 2430 // We can only fail the whole thing if no request has been 2431 // submitted yet. Otherwise we'll wait for the submitted AIOs to 2432 // complete and report the error in the callback. 2433 if (i == 0) { 2434 trace_bdrv_aio_multiwrite_earlyfail(mcb); 2435 goto fail; 2436 } else { 2437 trace_bdrv_aio_multiwrite_latefail(mcb, i); 2438 multiwrite_cb(mcb, -EIO); 2439 break; 2440 } 2441 } 2442 } 2443 2444 /* Complete the dummy request */ 2445 multiwrite_cb(mcb, 0); 2446 2447 return 0; 2448 2449 fail: 2450 for (i = 0; i < mcb->num_callbacks; i++) { 2451 reqs[i].error = -EIO; 2452 } 2453 qemu_free(mcb); 2454 return -1; 2455 } 2456 2457 BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs, 2458 BlockDriverCompletionFunc *cb, void *opaque) 2459 { 2460 BlockDriver *drv = bs->drv; 2461 2462 trace_bdrv_aio_flush(bs, opaque); 2463 2464 if (bs->open_flags & BDRV_O_NO_FLUSH) { 2465 return bdrv_aio_noop_em(bs, cb, opaque); 2466 } 2467 2468 if (!drv) 2469 return NULL; 2470 return drv->bdrv_aio_flush(bs, cb, opaque); 2471 } 2472 2473 void bdrv_aio_cancel(BlockDriverAIOCB *acb) 2474 { 2475 acb->pool->cancel(acb); 2476 } 2477 2478 2479 /**************************************************************/ 2480 /* async block device emulation */ 2481 2482 typedef struct BlockDriverAIOCBSync { 2483 BlockDriverAIOCB common; 2484 QEMUBH *bh; 2485 int ret; 2486 /* vector translation state */ 2487 QEMUIOVector *qiov; 2488 uint8_t *bounce; 2489 int is_write; 2490 } BlockDriverAIOCBSync; 2491 2492 static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb) 2493 { 2494 BlockDriverAIOCBSync *acb = 2495 container_of(blockacb, BlockDriverAIOCBSync, common); 2496 qemu_bh_delete(acb->bh); 2497 acb->bh = NULL; 2498 qemu_aio_release(acb); 2499 } 2500 2501 static AIOPool bdrv_em_aio_pool = { 2502 .aiocb_size = sizeof(BlockDriverAIOCBSync), 2503 .cancel = bdrv_aio_cancel_em, 2504 }; 2505 2506 static void bdrv_aio_bh_cb(void *opaque) 2507 { 2508 BlockDriverAIOCBSync *acb = opaque; 2509 2510 if (!acb->is_write) 2511 qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size); 2512 qemu_vfree(acb->bounce); 2513 acb->common.cb(acb->common.opaque, acb->ret); 2514 qemu_bh_delete(acb->bh); 2515 acb->bh = NULL; 2516 qemu_aio_release(acb); 2517 } 2518 2519 static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs, 2520 int64_t sector_num, 2521 QEMUIOVector *qiov, 2522 int nb_sectors, 2523 BlockDriverCompletionFunc *cb, 2524 void *opaque, 2525 int is_write) 2526 2527 { 2528 BlockDriverAIOCBSync *acb; 2529 2530 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 2531 acb->is_write = is_write; 2532 acb->qiov = qiov; 2533 acb->bounce = qemu_blockalign(bs, qiov->size); 2534 2535 if (!acb->bh) 2536 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 2537 2538 if (is_write) { 2539 qemu_iovec_to_buffer(acb->qiov, acb->bounce); 2540 acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors); 2541 } else { 2542 acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors); 2543 } 2544 2545 qemu_bh_schedule(acb->bh); 2546 2547 return &acb->common; 2548 } 2549 2550 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 2551 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 2552 BlockDriverCompletionFunc *cb, void *opaque) 2553 { 2554 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); 2555 } 2556 2557 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 2558 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 2559 BlockDriverCompletionFunc *cb, void *opaque) 2560 { 2561 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); 2562 } 2563 2564 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs, 2565 BlockDriverCompletionFunc *cb, void *opaque) 2566 { 2567 BlockDriverAIOCBSync *acb; 2568 2569 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 2570 acb->is_write = 1; /* don't bounce in the completion hadler */ 2571 acb->qiov = NULL; 2572 acb->bounce = NULL; 2573 acb->ret = 0; 2574 2575 if (!acb->bh) 2576 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 2577 2578 bdrv_flush(bs); 2579 qemu_bh_schedule(acb->bh); 2580 return &acb->common; 2581 } 2582 2583 static BlockDriverAIOCB *bdrv_aio_noop_em(BlockDriverState *bs, 2584 BlockDriverCompletionFunc *cb, void *opaque) 2585 { 2586 BlockDriverAIOCBSync *acb; 2587 2588 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque); 2589 acb->is_write = 1; /* don't bounce in the completion handler */ 2590 acb->qiov = NULL; 2591 acb->bounce = NULL; 2592 acb->ret = 0; 2593 2594 if (!acb->bh) { 2595 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); 2596 } 2597 2598 qemu_bh_schedule(acb->bh); 2599 return &acb->common; 2600 } 2601 2602 /**************************************************************/ 2603 /* sync block device emulation */ 2604 2605 static void bdrv_rw_em_cb(void *opaque, int ret) 2606 { 2607 *(int *)opaque = ret; 2608 } 2609 2610 #define NOT_DONE 0x7fffffff 2611 2612 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num, 2613 uint8_t *buf, int nb_sectors) 2614 { 2615 int async_ret; 2616 BlockDriverAIOCB *acb; 2617 struct iovec iov; 2618 QEMUIOVector qiov; 2619 2620 async_context_push(); 2621 2622 async_ret = NOT_DONE; 2623 iov.iov_base = (void *)buf; 2624 iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE; 2625 qemu_iovec_init_external(&qiov, &iov, 1); 2626 acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors, 2627 bdrv_rw_em_cb, &async_ret); 2628 if (acb == NULL) { 2629 async_ret = -1; 2630 goto fail; 2631 } 2632 2633 while (async_ret == NOT_DONE) { 2634 qemu_aio_wait(); 2635 } 2636 2637 2638 fail: 2639 async_context_pop(); 2640 return async_ret; 2641 } 2642 2643 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num, 2644 const uint8_t *buf, int nb_sectors) 2645 { 2646 int async_ret; 2647 BlockDriverAIOCB *acb; 2648 struct iovec iov; 2649 QEMUIOVector qiov; 2650 2651 async_context_push(); 2652 2653 async_ret = NOT_DONE; 2654 iov.iov_base = (void *)buf; 2655 iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE; 2656 qemu_iovec_init_external(&qiov, &iov, 1); 2657 acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors, 2658 bdrv_rw_em_cb, &async_ret); 2659 if (acb == NULL) { 2660 async_ret = -1; 2661 goto fail; 2662 } 2663 while (async_ret == NOT_DONE) { 2664 qemu_aio_wait(); 2665 } 2666 2667 fail: 2668 async_context_pop(); 2669 return async_ret; 2670 } 2671 2672 void bdrv_init(void) 2673 { 2674 module_call_init(MODULE_INIT_BLOCK); 2675 } 2676 2677 void bdrv_init_with_whitelist(void) 2678 { 2679 use_bdrv_whitelist = 1; 2680 bdrv_init(); 2681 } 2682 2683 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs, 2684 BlockDriverCompletionFunc *cb, void *opaque) 2685 { 2686 BlockDriverAIOCB *acb; 2687 2688 if (pool->free_aiocb) { 2689 acb = pool->free_aiocb; 2690 pool->free_aiocb = acb->next; 2691 } else { 2692 acb = qemu_mallocz(pool->aiocb_size); 2693 acb->pool = pool; 2694 } 2695 acb->bs = bs; 2696 acb->cb = cb; 2697 acb->opaque = opaque; 2698 return acb; 2699 } 2700 2701 void qemu_aio_release(void *p) 2702 { 2703 BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p; 2704 AIOPool *pool = acb->pool; 2705 acb->next = pool->free_aiocb; 2706 pool->free_aiocb = acb; 2707 } 2708 2709 /**************************************************************/ 2710 /* removable device support */ 2711 2712 /** 2713 * Return TRUE if the media is present 2714 */ 2715 int bdrv_is_inserted(BlockDriverState *bs) 2716 { 2717 BlockDriver *drv = bs->drv; 2718 int ret; 2719 if (!drv) 2720 return 0; 2721 if (!drv->bdrv_is_inserted) 2722 return !bs->tray_open; 2723 ret = drv->bdrv_is_inserted(bs); 2724 return ret; 2725 } 2726 2727 /** 2728 * Return TRUE if the media changed since the last call to this 2729 * function. It is currently only used for floppy disks 2730 */ 2731 int bdrv_media_changed(BlockDriverState *bs) 2732 { 2733 BlockDriver *drv = bs->drv; 2734 int ret; 2735 2736 if (!drv || !drv->bdrv_media_changed) 2737 ret = -ENOTSUP; 2738 else 2739 ret = drv->bdrv_media_changed(bs); 2740 if (ret == -ENOTSUP) 2741 ret = bs->media_changed; 2742 bs->media_changed = 0; 2743 return ret; 2744 } 2745 2746 /** 2747 * If eject_flag is TRUE, eject the media. Otherwise, close the tray 2748 */ 2749 int bdrv_eject(BlockDriverState *bs, int eject_flag) 2750 { 2751 BlockDriver *drv = bs->drv; 2752 int ret; 2753 2754 if (bs->locked) { 2755 return -EBUSY; 2756 } 2757 2758 if (!drv || !drv->bdrv_eject) { 2759 ret = -ENOTSUP; 2760 } else { 2761 ret = drv->bdrv_eject(bs, eject_flag); 2762 } 2763 if (ret == -ENOTSUP) { 2764 ret = 0; 2765 } 2766 if (ret >= 0) { 2767 bs->tray_open = eject_flag; 2768 } 2769 2770 return ret; 2771 } 2772 2773 int bdrv_is_locked(BlockDriverState *bs) 2774 { 2775 return bs->locked; 2776 } 2777 2778 /** 2779 * Lock or unlock the media (if it is locked, the user won't be able 2780 * to eject it manually). 2781 */ 2782 void bdrv_set_locked(BlockDriverState *bs, int locked) 2783 { 2784 BlockDriver *drv = bs->drv; 2785 2786 trace_bdrv_set_locked(bs, locked); 2787 2788 bs->locked = locked; 2789 if (drv && drv->bdrv_set_locked) { 2790 drv->bdrv_set_locked(bs, locked); 2791 } 2792 } 2793 2794 /* needed for generic scsi interface */ 2795 2796 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) 2797 { 2798 BlockDriver *drv = bs->drv; 2799 2800 if (drv && drv->bdrv_ioctl) 2801 return drv->bdrv_ioctl(bs, req, buf); 2802 return -ENOTSUP; 2803 } 2804 2805 BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, 2806 unsigned long int req, void *buf, 2807 BlockDriverCompletionFunc *cb, void *opaque) 2808 { 2809 BlockDriver *drv = bs->drv; 2810 2811 if (drv && drv->bdrv_aio_ioctl) 2812 return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); 2813 return NULL; 2814 } 2815 2816 2817 2818 void *qemu_blockalign(BlockDriverState *bs, size_t size) 2819 { 2820 return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size); 2821 } 2822 2823 void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable) 2824 { 2825 int64_t bitmap_size; 2826 2827 bs->dirty_count = 0; 2828 if (enable) { 2829 if (!bs->dirty_bitmap) { 2830 bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) + 2831 BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1; 2832 bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8; 2833 2834 bs->dirty_bitmap = qemu_mallocz(bitmap_size); 2835 } 2836 } else { 2837 if (bs->dirty_bitmap) { 2838 qemu_free(bs->dirty_bitmap); 2839 bs->dirty_bitmap = NULL; 2840 } 2841 } 2842 } 2843 2844 int bdrv_get_dirty(BlockDriverState *bs, int64_t sector) 2845 { 2846 int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK; 2847 2848 if (bs->dirty_bitmap && 2849 (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) { 2850 return !!(bs->dirty_bitmap[chunk / (sizeof(unsigned long) * 8)] & 2851 (1UL << (chunk % (sizeof(unsigned long) * 8)))); 2852 } else { 2853 return 0; 2854 } 2855 } 2856 2857 void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, 2858 int nr_sectors) 2859 { 2860 set_dirty_bitmap(bs, cur_sector, nr_sectors, 0); 2861 } 2862 2863 int64_t bdrv_get_dirty_count(BlockDriverState *bs) 2864 { 2865 return bs->dirty_count; 2866 } 2867 2868 void bdrv_set_in_use(BlockDriverState *bs, int in_use) 2869 { 2870 assert(bs->in_use != in_use); 2871 bs->in_use = in_use; 2872 } 2873 2874 int bdrv_in_use(BlockDriverState *bs) 2875 { 2876 return bs->in_use; 2877 } 2878 2879 int bdrv_img_create(const char *filename, const char *fmt, 2880 const char *base_filename, const char *base_fmt, 2881 char *options, uint64_t img_size, int flags) 2882 { 2883 QEMUOptionParameter *param = NULL, *create_options = NULL; 2884 QEMUOptionParameter *backing_fmt, *backing_file, *size; 2885 BlockDriverState *bs = NULL; 2886 BlockDriver *drv, *proto_drv; 2887 BlockDriver *backing_drv = NULL; 2888 int ret = 0; 2889 2890 /* Find driver and parse its options */ 2891 drv = bdrv_find_format(fmt); 2892 if (!drv) { 2893 error_report("Unknown file format '%s'", fmt); 2894 ret = -EINVAL; 2895 goto out; 2896 } 2897 2898 proto_drv = bdrv_find_protocol(filename); 2899 if (!proto_drv) { 2900 error_report("Unknown protocol '%s'", filename); 2901 ret = -EINVAL; 2902 goto out; 2903 } 2904 2905 create_options = append_option_parameters(create_options, 2906 drv->create_options); 2907 create_options = append_option_parameters(create_options, 2908 proto_drv->create_options); 2909 2910 /* Create parameter list with default values */ 2911 param = parse_option_parameters("", create_options, param); 2912 2913 set_option_parameter_int(param, BLOCK_OPT_SIZE, img_size); 2914 2915 /* Parse -o options */ 2916 if (options) { 2917 param = parse_option_parameters(options, create_options, param); 2918 if (param == NULL) { 2919 error_report("Invalid options for file format '%s'.", fmt); 2920 ret = -EINVAL; 2921 goto out; 2922 } 2923 } 2924 2925 if (base_filename) { 2926 if (set_option_parameter(param, BLOCK_OPT_BACKING_FILE, 2927 base_filename)) { 2928 error_report("Backing file not supported for file format '%s'", 2929 fmt); 2930 ret = -EINVAL; 2931 goto out; 2932 } 2933 } 2934 2935 if (base_fmt) { 2936 if (set_option_parameter(param, BLOCK_OPT_BACKING_FMT, base_fmt)) { 2937 error_report("Backing file format not supported for file " 2938 "format '%s'", fmt); 2939 ret = -EINVAL; 2940 goto out; 2941 } 2942 } 2943 2944 backing_file = get_option_parameter(param, BLOCK_OPT_BACKING_FILE); 2945 if (backing_file && backing_file->value.s) { 2946 if (!strcmp(filename, backing_file->value.s)) { 2947 error_report("Error: Trying to create an image with the " 2948 "same filename as the backing file"); 2949 ret = -EINVAL; 2950 goto out; 2951 } 2952 } 2953 2954 backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT); 2955 if (backing_fmt && backing_fmt->value.s) { 2956 backing_drv = bdrv_find_format(backing_fmt->value.s); 2957 if (!backing_drv) { 2958 error_report("Unknown backing file format '%s'", 2959 backing_fmt->value.s); 2960 ret = -EINVAL; 2961 goto out; 2962 } 2963 } 2964 2965 // The size for the image must always be specified, with one exception: 2966 // If we are using a backing file, we can obtain the size from there 2967 size = get_option_parameter(param, BLOCK_OPT_SIZE); 2968 if (size && size->value.n == -1) { 2969 if (backing_file && backing_file->value.s) { 2970 uint64_t size; 2971 char buf[32]; 2972 2973 bs = bdrv_new(""); 2974 2975 ret = bdrv_open(bs, backing_file->value.s, flags, backing_drv); 2976 if (ret < 0) { 2977 error_report("Could not open '%s'", backing_file->value.s); 2978 goto out; 2979 } 2980 bdrv_get_geometry(bs, &size); 2981 size *= 512; 2982 2983 snprintf(buf, sizeof(buf), "%" PRId64, size); 2984 set_option_parameter(param, BLOCK_OPT_SIZE, buf); 2985 } else { 2986 error_report("Image creation needs a size parameter"); 2987 ret = -EINVAL; 2988 goto out; 2989 } 2990 } 2991 2992 printf("Formatting '%s', fmt=%s ", filename, fmt); 2993 print_option_parameters(param); 2994 puts(""); 2995 2996 ret = bdrv_create(drv, filename, param); 2997 2998 if (ret < 0) { 2999 if (ret == -ENOTSUP) { 3000 error_report("Formatting or formatting option not supported for " 3001 "file format '%s'", fmt); 3002 } else if (ret == -EFBIG) { 3003 error_report("The image size is too large for file format '%s'", 3004 fmt); 3005 } else { 3006 error_report("%s: error while creating %s: %s", filename, fmt, 3007 strerror(-ret)); 3008 } 3009 } 3010 3011 out: 3012 free_option_parameters(create_options); 3013 free_option_parameters(param); 3014 3015 if (bs) { 3016 bdrv_delete(bs); 3017 } 3018 3019 return ret; 3020 } 3021