1 /* 2 * Block driver for RAW files (posix) 3 * 4 * Copyright (c) 2006 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 25 #include "qemu/osdep.h" 26 #include "qemu-common.h" 27 #include "qapi/error.h" 28 #include "qemu/cutils.h" 29 #include "qemu/error-report.h" 30 #include "block/block_int.h" 31 #include "qemu/module.h" 32 #include "qemu/option.h" 33 #include "trace.h" 34 #include "block/thread-pool.h" 35 #include "qemu/iov.h" 36 #include "block/raw-aio.h" 37 #include "qapi/qmp/qdict.h" 38 #include "qapi/qmp/qstring.h" 39 40 #include "scsi/pr-manager.h" 41 #include "scsi/constants.h" 42 43 #if defined(__APPLE__) && (__MACH__) 44 #include <paths.h> 45 #include <sys/param.h> 46 #include <IOKit/IOKitLib.h> 47 #include <IOKit/IOBSD.h> 48 #include <IOKit/storage/IOMediaBSDClient.h> 49 #include <IOKit/storage/IOMedia.h> 50 #include <IOKit/storage/IOCDMedia.h> 51 //#include <IOKit/storage/IOCDTypes.h> 52 #include <IOKit/storage/IODVDMedia.h> 53 #include <CoreFoundation/CoreFoundation.h> 54 #endif 55 56 #ifdef __sun__ 57 #define _POSIX_PTHREAD_SEMANTICS 1 58 #include <sys/dkio.h> 59 #endif 60 #ifdef __linux__ 61 #include <sys/ioctl.h> 62 #include <sys/param.h> 63 #include <sys/syscall.h> 64 #include <linux/cdrom.h> 65 #include <linux/fd.h> 66 #include <linux/fs.h> 67 #include <linux/hdreg.h> 68 #include <scsi/sg.h> 69 #ifdef __s390__ 70 #include <asm/dasd.h> 71 #endif 72 #ifndef FS_NOCOW_FL 73 #define FS_NOCOW_FL 0x00800000 /* Do not cow file */ 74 #endif 75 #endif 76 #if defined(CONFIG_FALLOCATE_PUNCH_HOLE) || defined(CONFIG_FALLOCATE_ZERO_RANGE) 77 #include <linux/falloc.h> 78 #endif 79 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__) 80 #include <sys/disk.h> 81 #include <sys/cdio.h> 82 #endif 83 84 #ifdef __OpenBSD__ 85 #include <sys/ioctl.h> 86 #include <sys/disklabel.h> 87 #include <sys/dkio.h> 88 #endif 89 90 #ifdef __NetBSD__ 91 #include <sys/ioctl.h> 92 #include <sys/disklabel.h> 93 #include <sys/dkio.h> 94 #include <sys/disk.h> 95 #endif 96 97 #ifdef __DragonFly__ 98 #include <sys/ioctl.h> 99 #include <sys/diskslice.h> 100 #endif 101 102 #ifdef CONFIG_XFS 103 #include <xfs/xfs.h> 104 #endif 105 106 #include "trace.h" 107 108 /* OS X does not have O_DSYNC */ 109 #ifndef O_DSYNC 110 #ifdef O_SYNC 111 #define O_DSYNC O_SYNC 112 #elif defined(O_FSYNC) 113 #define O_DSYNC O_FSYNC 114 #endif 115 #endif 116 117 /* Approximate O_DIRECT with O_DSYNC if O_DIRECT isn't available */ 118 #ifndef O_DIRECT 119 #define O_DIRECT O_DSYNC 120 #endif 121 122 #define FTYPE_FILE 0 123 #define FTYPE_CD 1 124 125 #define MAX_BLOCKSIZE 4096 126 127 /* Posix file locking bytes. Libvirt takes byte 0, we start from higher bytes, 128 * leaving a few more bytes for its future use. */ 129 #define RAW_LOCK_PERM_BASE 100 130 #define RAW_LOCK_SHARED_BASE 200 131 132 typedef struct BDRVRawState { 133 int fd; 134 bool use_lock; 135 int type; 136 int open_flags; 137 size_t buf_align; 138 139 /* The current permissions. */ 140 uint64_t perm; 141 uint64_t shared_perm; 142 143 /* The perms bits whose corresponding bytes are already locked in 144 * s->fd. */ 145 uint64_t locked_perm; 146 uint64_t locked_shared_perm; 147 148 int perm_change_fd; 149 int perm_change_flags; 150 BDRVReopenState *reopen_state; 151 152 #ifdef CONFIG_XFS 153 bool is_xfs:1; 154 #endif 155 bool has_discard:1; 156 bool has_write_zeroes:1; 157 bool discard_zeroes:1; 158 bool use_linux_aio:1; 159 bool use_linux_io_uring:1; 160 bool page_cache_inconsistent:1; 161 bool has_fallocate; 162 bool needs_alignment; 163 bool drop_cache; 164 bool check_cache_dropped; 165 struct { 166 uint64_t discard_nb_ok; 167 uint64_t discard_nb_failed; 168 uint64_t discard_bytes_ok; 169 } stats; 170 171 PRManager *pr_mgr; 172 } BDRVRawState; 173 174 typedef struct BDRVRawReopenState { 175 int fd; 176 int open_flags; 177 bool drop_cache; 178 bool check_cache_dropped; 179 } BDRVRawReopenState; 180 181 static int fd_open(BlockDriverState *bs); 182 static int64_t raw_getlength(BlockDriverState *bs); 183 184 typedef struct RawPosixAIOData { 185 BlockDriverState *bs; 186 int aio_type; 187 int aio_fildes; 188 189 off_t aio_offset; 190 uint64_t aio_nbytes; 191 192 union { 193 struct { 194 struct iovec *iov; 195 int niov; 196 } io; 197 struct { 198 uint64_t cmd; 199 void *buf; 200 } ioctl; 201 struct { 202 int aio_fd2; 203 off_t aio_offset2; 204 } copy_range; 205 struct { 206 PreallocMode prealloc; 207 Error **errp; 208 } truncate; 209 }; 210 } RawPosixAIOData; 211 212 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) 213 static int cdrom_reopen(BlockDriverState *bs); 214 #endif 215 216 #if defined(__NetBSD__) 217 static int raw_normalize_devicepath(const char **filename, Error **errp) 218 { 219 static char namebuf[PATH_MAX]; 220 const char *dp, *fname; 221 struct stat sb; 222 223 fname = *filename; 224 dp = strrchr(fname, '/'); 225 if (lstat(fname, &sb) < 0) { 226 error_setg_file_open(errp, errno, fname); 227 return -errno; 228 } 229 230 if (!S_ISBLK(sb.st_mode)) { 231 return 0; 232 } 233 234 if (dp == NULL) { 235 snprintf(namebuf, PATH_MAX, "r%s", fname); 236 } else { 237 snprintf(namebuf, PATH_MAX, "%.*s/r%s", 238 (int)(dp - fname), fname, dp + 1); 239 } 240 *filename = namebuf; 241 warn_report("%s is a block device, using %s", fname, *filename); 242 243 return 0; 244 } 245 #else 246 static int raw_normalize_devicepath(const char **filename, Error **errp) 247 { 248 return 0; 249 } 250 #endif 251 252 /* 253 * Get logical block size via ioctl. On success store it in @sector_size_p. 254 */ 255 static int probe_logical_blocksize(int fd, unsigned int *sector_size_p) 256 { 257 unsigned int sector_size; 258 bool success = false; 259 int i; 260 261 errno = ENOTSUP; 262 static const unsigned long ioctl_list[] = { 263 #ifdef BLKSSZGET 264 BLKSSZGET, 265 #endif 266 #ifdef DKIOCGETBLOCKSIZE 267 DKIOCGETBLOCKSIZE, 268 #endif 269 #ifdef DIOCGSECTORSIZE 270 DIOCGSECTORSIZE, 271 #endif 272 }; 273 274 /* Try a few ioctls to get the right size */ 275 for (i = 0; i < (int)ARRAY_SIZE(ioctl_list); i++) { 276 if (ioctl(fd, ioctl_list[i], §or_size) >= 0) { 277 *sector_size_p = sector_size; 278 success = true; 279 } 280 } 281 282 return success ? 0 : -errno; 283 } 284 285 /** 286 * Get physical block size of @fd. 287 * On success, store it in @blk_size and return 0. 288 * On failure, return -errno. 289 */ 290 static int probe_physical_blocksize(int fd, unsigned int *blk_size) 291 { 292 #ifdef BLKPBSZGET 293 if (ioctl(fd, BLKPBSZGET, blk_size) < 0) { 294 return -errno; 295 } 296 return 0; 297 #else 298 return -ENOTSUP; 299 #endif 300 } 301 302 /* Check if read is allowed with given memory buffer and length. 303 * 304 * This function is used to check O_DIRECT memory buffer and request alignment. 305 */ 306 static bool raw_is_io_aligned(int fd, void *buf, size_t len) 307 { 308 ssize_t ret = pread(fd, buf, len, 0); 309 310 if (ret >= 0) { 311 return true; 312 } 313 314 #ifdef __linux__ 315 /* The Linux kernel returns EINVAL for misaligned O_DIRECT reads. Ignore 316 * other errors (e.g. real I/O error), which could happen on a failed 317 * drive, since we only care about probing alignment. 318 */ 319 if (errno != EINVAL) { 320 return true; 321 } 322 #endif 323 324 return false; 325 } 326 327 static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp) 328 { 329 BDRVRawState *s = bs->opaque; 330 char *buf; 331 size_t max_align = MAX(MAX_BLOCKSIZE, qemu_real_host_page_size); 332 size_t alignments[] = {1, 512, 1024, 2048, 4096}; 333 334 /* For SCSI generic devices the alignment is not really used. 335 With buffered I/O, we don't have any restrictions. */ 336 if (bdrv_is_sg(bs) || !s->needs_alignment) { 337 bs->bl.request_alignment = 1; 338 s->buf_align = 1; 339 return; 340 } 341 342 bs->bl.request_alignment = 0; 343 s->buf_align = 0; 344 /* Let's try to use the logical blocksize for the alignment. */ 345 if (probe_logical_blocksize(fd, &bs->bl.request_alignment) < 0) { 346 bs->bl.request_alignment = 0; 347 } 348 #ifdef CONFIG_XFS 349 if (s->is_xfs) { 350 struct dioattr da; 351 if (xfsctl(NULL, fd, XFS_IOC_DIOINFO, &da) >= 0) { 352 bs->bl.request_alignment = da.d_miniosz; 353 /* The kernel returns wrong information for d_mem */ 354 /* s->buf_align = da.d_mem; */ 355 } 356 } 357 #endif 358 359 /* 360 * If we could not get the sizes so far, we can only guess them. First try 361 * to detect request alignment, since it is more likely to succeed. Then 362 * try to detect buf_align, which cannot be detected in some cases (e.g. 363 * Gluster). If buf_align cannot be detected, we fallback to the value of 364 * request_alignment. 365 */ 366 367 if (!bs->bl.request_alignment) { 368 int i; 369 size_t align; 370 buf = qemu_memalign(max_align, max_align); 371 for (i = 0; i < ARRAY_SIZE(alignments); i++) { 372 align = alignments[i]; 373 if (raw_is_io_aligned(fd, buf, align)) { 374 /* Fallback to safe value. */ 375 bs->bl.request_alignment = (align != 1) ? align : max_align; 376 break; 377 } 378 } 379 qemu_vfree(buf); 380 } 381 382 if (!s->buf_align) { 383 int i; 384 size_t align; 385 buf = qemu_memalign(max_align, 2 * max_align); 386 for (i = 0; i < ARRAY_SIZE(alignments); i++) { 387 align = alignments[i]; 388 if (raw_is_io_aligned(fd, buf + align, max_align)) { 389 /* Fallback to request_alignment. */ 390 s->buf_align = (align != 1) ? align : bs->bl.request_alignment; 391 break; 392 } 393 } 394 qemu_vfree(buf); 395 } 396 397 if (!s->buf_align || !bs->bl.request_alignment) { 398 error_setg(errp, "Could not find working O_DIRECT alignment"); 399 error_append_hint(errp, "Try cache.direct=off\n"); 400 } 401 } 402 403 static void raw_parse_flags(int bdrv_flags, int *open_flags, bool has_writers) 404 { 405 bool read_write = false; 406 assert(open_flags != NULL); 407 408 *open_flags |= O_BINARY; 409 *open_flags &= ~O_ACCMODE; 410 411 if (bdrv_flags & BDRV_O_AUTO_RDONLY) { 412 read_write = has_writers; 413 } else if (bdrv_flags & BDRV_O_RDWR) { 414 read_write = true; 415 } 416 417 if (read_write) { 418 *open_flags |= O_RDWR; 419 } else { 420 *open_flags |= O_RDONLY; 421 } 422 423 /* Use O_DSYNC for write-through caching, no flags for write-back caching, 424 * and O_DIRECT for no caching. */ 425 if ((bdrv_flags & BDRV_O_NOCACHE)) { 426 *open_flags |= O_DIRECT; 427 } 428 } 429 430 static void raw_parse_filename(const char *filename, QDict *options, 431 Error **errp) 432 { 433 bdrv_parse_filename_strip_prefix(filename, "file:", options); 434 } 435 436 static QemuOptsList raw_runtime_opts = { 437 .name = "raw", 438 .head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head), 439 .desc = { 440 { 441 .name = "filename", 442 .type = QEMU_OPT_STRING, 443 .help = "File name of the image", 444 }, 445 { 446 .name = "aio", 447 .type = QEMU_OPT_STRING, 448 .help = "host AIO implementation (threads, native, io_uring)", 449 }, 450 { 451 .name = "locking", 452 .type = QEMU_OPT_STRING, 453 .help = "file locking mode (on/off/auto, default: auto)", 454 }, 455 { 456 .name = "pr-manager", 457 .type = QEMU_OPT_STRING, 458 .help = "id of persistent reservation manager object (default: none)", 459 }, 460 #if defined(__linux__) 461 { 462 .name = "drop-cache", 463 .type = QEMU_OPT_BOOL, 464 .help = "invalidate page cache during live migration (default: on)", 465 }, 466 #endif 467 { 468 .name = "x-check-cache-dropped", 469 .type = QEMU_OPT_BOOL, 470 .help = "check that page cache was dropped on live migration (default: off)" 471 }, 472 { /* end of list */ } 473 }, 474 }; 475 476 static const char *const mutable_opts[] = { "x-check-cache-dropped", NULL }; 477 478 static int raw_open_common(BlockDriverState *bs, QDict *options, 479 int bdrv_flags, int open_flags, 480 bool device, Error **errp) 481 { 482 BDRVRawState *s = bs->opaque; 483 QemuOpts *opts; 484 Error *local_err = NULL; 485 const char *filename = NULL; 486 const char *str; 487 BlockdevAioOptions aio, aio_default; 488 int fd, ret; 489 struct stat st; 490 OnOffAuto locking; 491 492 opts = qemu_opts_create(&raw_runtime_opts, NULL, 0, &error_abort); 493 if (!qemu_opts_absorb_qdict(opts, options, &local_err)) { 494 error_propagate(errp, local_err); 495 ret = -EINVAL; 496 goto fail; 497 } 498 499 filename = qemu_opt_get(opts, "filename"); 500 501 ret = raw_normalize_devicepath(&filename, errp); 502 if (ret != 0) { 503 goto fail; 504 } 505 506 if (bdrv_flags & BDRV_O_NATIVE_AIO) { 507 aio_default = BLOCKDEV_AIO_OPTIONS_NATIVE; 508 #ifdef CONFIG_LINUX_IO_URING 509 } else if (bdrv_flags & BDRV_O_IO_URING) { 510 aio_default = BLOCKDEV_AIO_OPTIONS_IO_URING; 511 #endif 512 } else { 513 aio_default = BLOCKDEV_AIO_OPTIONS_THREADS; 514 } 515 516 aio = qapi_enum_parse(&BlockdevAioOptions_lookup, 517 qemu_opt_get(opts, "aio"), 518 aio_default, &local_err); 519 if (local_err) { 520 error_propagate(errp, local_err); 521 ret = -EINVAL; 522 goto fail; 523 } 524 525 s->use_linux_aio = (aio == BLOCKDEV_AIO_OPTIONS_NATIVE); 526 #ifdef CONFIG_LINUX_IO_URING 527 s->use_linux_io_uring = (aio == BLOCKDEV_AIO_OPTIONS_IO_URING); 528 #endif 529 530 locking = qapi_enum_parse(&OnOffAuto_lookup, 531 qemu_opt_get(opts, "locking"), 532 ON_OFF_AUTO_AUTO, &local_err); 533 if (local_err) { 534 error_propagate(errp, local_err); 535 ret = -EINVAL; 536 goto fail; 537 } 538 switch (locking) { 539 case ON_OFF_AUTO_ON: 540 s->use_lock = true; 541 if (!qemu_has_ofd_lock()) { 542 warn_report("File lock requested but OFD locking syscall is " 543 "unavailable, falling back to POSIX file locks"); 544 error_printf("Due to the implementation, locks can be lost " 545 "unexpectedly.\n"); 546 } 547 break; 548 case ON_OFF_AUTO_OFF: 549 s->use_lock = false; 550 break; 551 case ON_OFF_AUTO_AUTO: 552 s->use_lock = qemu_has_ofd_lock(); 553 break; 554 default: 555 abort(); 556 } 557 558 str = qemu_opt_get(opts, "pr-manager"); 559 if (str) { 560 s->pr_mgr = pr_manager_lookup(str, &local_err); 561 if (local_err) { 562 error_propagate(errp, local_err); 563 ret = -EINVAL; 564 goto fail; 565 } 566 } 567 568 s->drop_cache = qemu_opt_get_bool(opts, "drop-cache", true); 569 s->check_cache_dropped = qemu_opt_get_bool(opts, "x-check-cache-dropped", 570 false); 571 572 s->open_flags = open_flags; 573 raw_parse_flags(bdrv_flags, &s->open_flags, false); 574 575 s->fd = -1; 576 fd = qemu_open(filename, s->open_flags, 0644); 577 ret = fd < 0 ? -errno : 0; 578 579 if (ret < 0) { 580 error_setg_file_open(errp, -ret, filename); 581 if (ret == -EROFS) { 582 ret = -EACCES; 583 } 584 goto fail; 585 } 586 s->fd = fd; 587 588 s->perm = 0; 589 s->shared_perm = BLK_PERM_ALL; 590 591 #ifdef CONFIG_LINUX_AIO 592 /* Currently Linux does AIO only for files opened with O_DIRECT */ 593 if (s->use_linux_aio) { 594 if (!(s->open_flags & O_DIRECT)) { 595 error_setg(errp, "aio=native was specified, but it requires " 596 "cache.direct=on, which was not specified."); 597 ret = -EINVAL; 598 goto fail; 599 } 600 if (!aio_setup_linux_aio(bdrv_get_aio_context(bs), errp)) { 601 error_prepend(errp, "Unable to use native AIO: "); 602 goto fail; 603 } 604 } 605 #else 606 if (s->use_linux_aio) { 607 error_setg(errp, "aio=native was specified, but is not supported " 608 "in this build."); 609 ret = -EINVAL; 610 goto fail; 611 } 612 #endif /* !defined(CONFIG_LINUX_AIO) */ 613 614 #ifdef CONFIG_LINUX_IO_URING 615 if (s->use_linux_io_uring) { 616 if (!aio_setup_linux_io_uring(bdrv_get_aio_context(bs), errp)) { 617 error_prepend(errp, "Unable to use io_uring: "); 618 goto fail; 619 } 620 } 621 #else 622 if (s->use_linux_io_uring) { 623 error_setg(errp, "aio=io_uring was specified, but is not supported " 624 "in this build."); 625 ret = -EINVAL; 626 goto fail; 627 } 628 #endif /* !defined(CONFIG_LINUX_IO_URING) */ 629 630 s->has_discard = true; 631 s->has_write_zeroes = true; 632 if ((bs->open_flags & BDRV_O_NOCACHE) != 0) { 633 s->needs_alignment = true; 634 } 635 636 if (fstat(s->fd, &st) < 0) { 637 ret = -errno; 638 error_setg_errno(errp, errno, "Could not stat file"); 639 goto fail; 640 } 641 642 if (!device) { 643 if (S_ISBLK(st.st_mode)) { 644 warn_report("Opening a block device as a file using the '%s' " 645 "driver is deprecated", bs->drv->format_name); 646 } else if (S_ISCHR(st.st_mode)) { 647 warn_report("Opening a character device as a file using the '%s' " 648 "driver is deprecated", bs->drv->format_name); 649 } else if (!S_ISREG(st.st_mode)) { 650 error_setg(errp, "A regular file was expected by the '%s' driver, " 651 "but something else was given", bs->drv->format_name); 652 ret = -EINVAL; 653 goto fail; 654 } else { 655 s->discard_zeroes = true; 656 s->has_fallocate = true; 657 } 658 } else { 659 if (!(S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) { 660 error_setg(errp, "'%s' driver expects either " 661 "a character or block device", bs->drv->format_name); 662 ret = -EINVAL; 663 goto fail; 664 } 665 } 666 667 if (S_ISBLK(st.st_mode)) { 668 #ifdef BLKDISCARDZEROES 669 unsigned int arg; 670 if (ioctl(s->fd, BLKDISCARDZEROES, &arg) == 0 && arg) { 671 s->discard_zeroes = true; 672 } 673 #endif 674 #ifdef __linux__ 675 /* On Linux 3.10, BLKDISCARD leaves stale data in the page cache. Do 676 * not rely on the contents of discarded blocks unless using O_DIRECT. 677 * Same for BLKZEROOUT. 678 */ 679 if (!(bs->open_flags & BDRV_O_NOCACHE)) { 680 s->discard_zeroes = false; 681 s->has_write_zeroes = false; 682 } 683 #endif 684 } 685 #ifdef __FreeBSD__ 686 if (S_ISCHR(st.st_mode)) { 687 /* 688 * The file is a char device (disk), which on FreeBSD isn't behind 689 * a pager, so force all requests to be aligned. This is needed 690 * so QEMU makes sure all IO operations on the device are aligned 691 * to sector size, or else FreeBSD will reject them with EINVAL. 692 */ 693 s->needs_alignment = true; 694 } 695 #endif 696 697 #ifdef CONFIG_XFS 698 if (platform_test_xfs_fd(s->fd)) { 699 s->is_xfs = true; 700 } 701 #endif 702 703 bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK; 704 if (S_ISREG(st.st_mode)) { 705 /* When extending regular files, we get zeros from the OS */ 706 bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; 707 } 708 ret = 0; 709 fail: 710 if (filename && (bdrv_flags & BDRV_O_TEMPORARY)) { 711 unlink(filename); 712 } 713 qemu_opts_del(opts); 714 return ret; 715 } 716 717 static int raw_open(BlockDriverState *bs, QDict *options, int flags, 718 Error **errp) 719 { 720 BDRVRawState *s = bs->opaque; 721 722 s->type = FTYPE_FILE; 723 return raw_open_common(bs, options, flags, 0, false, errp); 724 } 725 726 typedef enum { 727 RAW_PL_PREPARE, 728 RAW_PL_COMMIT, 729 RAW_PL_ABORT, 730 } RawPermLockOp; 731 732 #define PERM_FOREACH(i) \ 733 for ((i) = 0; (1ULL << (i)) <= BLK_PERM_ALL; i++) 734 735 /* Lock bytes indicated by @perm_lock_bits and @shared_perm_lock_bits in the 736 * file; if @unlock == true, also unlock the unneeded bytes. 737 * @shared_perm_lock_bits is the mask of all permissions that are NOT shared. 738 */ 739 static int raw_apply_lock_bytes(BDRVRawState *s, int fd, 740 uint64_t perm_lock_bits, 741 uint64_t shared_perm_lock_bits, 742 bool unlock, Error **errp) 743 { 744 int ret; 745 int i; 746 uint64_t locked_perm, locked_shared_perm; 747 748 if (s) { 749 locked_perm = s->locked_perm; 750 locked_shared_perm = s->locked_shared_perm; 751 } else { 752 /* 753 * We don't have the previous bits, just lock/unlock for each of the 754 * requested bits. 755 */ 756 if (unlock) { 757 locked_perm = BLK_PERM_ALL; 758 locked_shared_perm = BLK_PERM_ALL; 759 } else { 760 locked_perm = 0; 761 locked_shared_perm = 0; 762 } 763 } 764 765 PERM_FOREACH(i) { 766 int off = RAW_LOCK_PERM_BASE + i; 767 uint64_t bit = (1ULL << i); 768 if ((perm_lock_bits & bit) && !(locked_perm & bit)) { 769 ret = qemu_lock_fd(fd, off, 1, false); 770 if (ret) { 771 error_setg(errp, "Failed to lock byte %d", off); 772 return ret; 773 } else if (s) { 774 s->locked_perm |= bit; 775 } 776 } else if (unlock && (locked_perm & bit) && !(perm_lock_bits & bit)) { 777 ret = qemu_unlock_fd(fd, off, 1); 778 if (ret) { 779 error_setg(errp, "Failed to unlock byte %d", off); 780 return ret; 781 } else if (s) { 782 s->locked_perm &= ~bit; 783 } 784 } 785 } 786 PERM_FOREACH(i) { 787 int off = RAW_LOCK_SHARED_BASE + i; 788 uint64_t bit = (1ULL << i); 789 if ((shared_perm_lock_bits & bit) && !(locked_shared_perm & bit)) { 790 ret = qemu_lock_fd(fd, off, 1, false); 791 if (ret) { 792 error_setg(errp, "Failed to lock byte %d", off); 793 return ret; 794 } else if (s) { 795 s->locked_shared_perm |= bit; 796 } 797 } else if (unlock && (locked_shared_perm & bit) && 798 !(shared_perm_lock_bits & bit)) { 799 ret = qemu_unlock_fd(fd, off, 1); 800 if (ret) { 801 error_setg(errp, "Failed to unlock byte %d", off); 802 return ret; 803 } else if (s) { 804 s->locked_shared_perm &= ~bit; 805 } 806 } 807 } 808 return 0; 809 } 810 811 /* Check "unshared" bytes implied by @perm and ~@shared_perm in the file. */ 812 static int raw_check_lock_bytes(int fd, uint64_t perm, uint64_t shared_perm, 813 Error **errp) 814 { 815 int ret; 816 int i; 817 818 PERM_FOREACH(i) { 819 int off = RAW_LOCK_SHARED_BASE + i; 820 uint64_t p = 1ULL << i; 821 if (perm & p) { 822 ret = qemu_lock_fd_test(fd, off, 1, true); 823 if (ret) { 824 char *perm_name = bdrv_perm_names(p); 825 error_setg(errp, 826 "Failed to get \"%s\" lock", 827 perm_name); 828 g_free(perm_name); 829 return ret; 830 } 831 } 832 } 833 PERM_FOREACH(i) { 834 int off = RAW_LOCK_PERM_BASE + i; 835 uint64_t p = 1ULL << i; 836 if (!(shared_perm & p)) { 837 ret = qemu_lock_fd_test(fd, off, 1, true); 838 if (ret) { 839 char *perm_name = bdrv_perm_names(p); 840 error_setg(errp, 841 "Failed to get shared \"%s\" lock", 842 perm_name); 843 g_free(perm_name); 844 return ret; 845 } 846 } 847 } 848 return 0; 849 } 850 851 static int raw_handle_perm_lock(BlockDriverState *bs, 852 RawPermLockOp op, 853 uint64_t new_perm, uint64_t new_shared, 854 Error **errp) 855 { 856 BDRVRawState *s = bs->opaque; 857 int ret = 0; 858 Error *local_err = NULL; 859 860 if (!s->use_lock) { 861 return 0; 862 } 863 864 if (bdrv_get_flags(bs) & BDRV_O_INACTIVE) { 865 return 0; 866 } 867 868 switch (op) { 869 case RAW_PL_PREPARE: 870 if ((s->perm | new_perm) == s->perm && 871 (s->shared_perm & new_shared) == s->shared_perm) 872 { 873 /* 874 * We are going to unlock bytes, it should not fail. If it fail due 875 * to some fs-dependent permission-unrelated reasons (which occurs 876 * sometimes on NFS and leads to abort in bdrv_replace_child) we 877 * can't prevent such errors by any check here. And we ignore them 878 * anyway in ABORT and COMMIT. 879 */ 880 return 0; 881 } 882 ret = raw_apply_lock_bytes(s, s->fd, s->perm | new_perm, 883 ~s->shared_perm | ~new_shared, 884 false, errp); 885 if (!ret) { 886 ret = raw_check_lock_bytes(s->fd, new_perm, new_shared, errp); 887 if (!ret) { 888 return 0; 889 } 890 error_append_hint(errp, 891 "Is another process using the image [%s]?\n", 892 bs->filename); 893 } 894 /* fall through to unlock bytes. */ 895 case RAW_PL_ABORT: 896 raw_apply_lock_bytes(s, s->fd, s->perm, ~s->shared_perm, 897 true, &local_err); 898 if (local_err) { 899 /* Theoretically the above call only unlocks bytes and it cannot 900 * fail. Something weird happened, report it. 901 */ 902 warn_report_err(local_err); 903 } 904 break; 905 case RAW_PL_COMMIT: 906 raw_apply_lock_bytes(s, s->fd, new_perm, ~new_shared, 907 true, &local_err); 908 if (local_err) { 909 /* Theoretically the above call only unlocks bytes and it cannot 910 * fail. Something weird happened, report it. 911 */ 912 warn_report_err(local_err); 913 } 914 break; 915 } 916 return ret; 917 } 918 919 static int raw_reconfigure_getfd(BlockDriverState *bs, int flags, 920 int *open_flags, uint64_t perm, bool force_dup, 921 Error **errp) 922 { 923 BDRVRawState *s = bs->opaque; 924 int fd = -1; 925 int ret; 926 bool has_writers = perm & 927 (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED | BLK_PERM_RESIZE); 928 int fcntl_flags = O_APPEND | O_NONBLOCK; 929 #ifdef O_NOATIME 930 fcntl_flags |= O_NOATIME; 931 #endif 932 933 *open_flags = 0; 934 if (s->type == FTYPE_CD) { 935 *open_flags |= O_NONBLOCK; 936 } 937 938 raw_parse_flags(flags, open_flags, has_writers); 939 940 #ifdef O_ASYNC 941 /* Not all operating systems have O_ASYNC, and those that don't 942 * will not let us track the state into rs->open_flags (typically 943 * you achieve the same effect with an ioctl, for example I_SETSIG 944 * on Solaris). But we do not use O_ASYNC, so that's fine. 945 */ 946 assert((s->open_flags & O_ASYNC) == 0); 947 #endif 948 949 if (!force_dup && *open_flags == s->open_flags) { 950 /* We're lucky, the existing fd is fine */ 951 return s->fd; 952 } 953 954 if ((*open_flags & ~fcntl_flags) == (s->open_flags & ~fcntl_flags)) { 955 /* dup the original fd */ 956 fd = qemu_dup(s->fd); 957 if (fd >= 0) { 958 ret = fcntl_setfl(fd, *open_flags); 959 if (ret) { 960 qemu_close(fd); 961 fd = -1; 962 } 963 } 964 } 965 966 /* If we cannot use fcntl, or fcntl failed, fall back to qemu_open() */ 967 if (fd == -1) { 968 const char *normalized_filename = bs->filename; 969 ret = raw_normalize_devicepath(&normalized_filename, errp); 970 if (ret >= 0) { 971 assert(!(*open_flags & O_CREAT)); 972 fd = qemu_open(normalized_filename, *open_flags); 973 if (fd == -1) { 974 error_setg_errno(errp, errno, "Could not reopen file"); 975 return -1; 976 } 977 } 978 } 979 980 return fd; 981 } 982 983 static int raw_reopen_prepare(BDRVReopenState *state, 984 BlockReopenQueue *queue, Error **errp) 985 { 986 BDRVRawState *s; 987 BDRVRawReopenState *rs; 988 QemuOpts *opts; 989 int ret; 990 Error *local_err = NULL; 991 992 assert(state != NULL); 993 assert(state->bs != NULL); 994 995 s = state->bs->opaque; 996 997 state->opaque = g_new0(BDRVRawReopenState, 1); 998 rs = state->opaque; 999 1000 /* Handle options changes */ 1001 opts = qemu_opts_create(&raw_runtime_opts, NULL, 0, &error_abort); 1002 if (!qemu_opts_absorb_qdict(opts, state->options, &local_err)) { 1003 error_propagate(errp, local_err); 1004 ret = -EINVAL; 1005 goto out; 1006 } 1007 1008 rs->drop_cache = qemu_opt_get_bool_del(opts, "drop-cache", true); 1009 rs->check_cache_dropped = 1010 qemu_opt_get_bool_del(opts, "x-check-cache-dropped", false); 1011 1012 /* This driver's reopen function doesn't currently allow changing 1013 * other options, so let's put them back in the original QDict and 1014 * bdrv_reopen_prepare() will detect changes and complain. */ 1015 qemu_opts_to_qdict(opts, state->options); 1016 1017 rs->fd = raw_reconfigure_getfd(state->bs, state->flags, &rs->open_flags, 1018 state->perm, true, &local_err); 1019 if (local_err) { 1020 error_propagate(errp, local_err); 1021 ret = -1; 1022 goto out; 1023 } 1024 1025 /* Fail already reopen_prepare() if we can't get a working O_DIRECT 1026 * alignment with the new fd. */ 1027 if (rs->fd != -1) { 1028 raw_probe_alignment(state->bs, rs->fd, &local_err); 1029 if (local_err) { 1030 error_propagate(errp, local_err); 1031 ret = -EINVAL; 1032 goto out_fd; 1033 } 1034 } 1035 1036 s->reopen_state = state; 1037 ret = 0; 1038 out_fd: 1039 if (ret < 0) { 1040 qemu_close(rs->fd); 1041 rs->fd = -1; 1042 } 1043 out: 1044 qemu_opts_del(opts); 1045 return ret; 1046 } 1047 1048 static void raw_reopen_commit(BDRVReopenState *state) 1049 { 1050 BDRVRawReopenState *rs = state->opaque; 1051 BDRVRawState *s = state->bs->opaque; 1052 1053 s->drop_cache = rs->drop_cache; 1054 s->check_cache_dropped = rs->check_cache_dropped; 1055 s->open_flags = rs->open_flags; 1056 1057 qemu_close(s->fd); 1058 s->fd = rs->fd; 1059 1060 g_free(state->opaque); 1061 state->opaque = NULL; 1062 1063 assert(s->reopen_state == state); 1064 s->reopen_state = NULL; 1065 } 1066 1067 1068 static void raw_reopen_abort(BDRVReopenState *state) 1069 { 1070 BDRVRawReopenState *rs = state->opaque; 1071 BDRVRawState *s = state->bs->opaque; 1072 1073 /* nothing to do if NULL, we didn't get far enough */ 1074 if (rs == NULL) { 1075 return; 1076 } 1077 1078 if (rs->fd >= 0) { 1079 qemu_close(rs->fd); 1080 rs->fd = -1; 1081 } 1082 g_free(state->opaque); 1083 state->opaque = NULL; 1084 1085 assert(s->reopen_state == state); 1086 s->reopen_state = NULL; 1087 } 1088 1089 static int sg_get_max_transfer_length(int fd) 1090 { 1091 #ifdef BLKSECTGET 1092 int max_bytes = 0; 1093 1094 if (ioctl(fd, BLKSECTGET, &max_bytes) == 0) { 1095 return max_bytes; 1096 } else { 1097 return -errno; 1098 } 1099 #else 1100 return -ENOSYS; 1101 #endif 1102 } 1103 1104 static int sg_get_max_segments(int fd) 1105 { 1106 #ifdef CONFIG_LINUX 1107 char buf[32]; 1108 const char *end; 1109 char *sysfspath = NULL; 1110 int ret; 1111 int sysfd = -1; 1112 long max_segments; 1113 struct stat st; 1114 1115 if (fstat(fd, &st)) { 1116 ret = -errno; 1117 goto out; 1118 } 1119 1120 sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/max_segments", 1121 major(st.st_rdev), minor(st.st_rdev)); 1122 sysfd = open(sysfspath, O_RDONLY); 1123 if (sysfd == -1) { 1124 ret = -errno; 1125 goto out; 1126 } 1127 do { 1128 ret = read(sysfd, buf, sizeof(buf) - 1); 1129 } while (ret == -1 && errno == EINTR); 1130 if (ret < 0) { 1131 ret = -errno; 1132 goto out; 1133 } else if (ret == 0) { 1134 ret = -EIO; 1135 goto out; 1136 } 1137 buf[ret] = 0; 1138 /* The file is ended with '\n', pass 'end' to accept that. */ 1139 ret = qemu_strtol(buf, &end, 10, &max_segments); 1140 if (ret == 0 && end && *end == '\n') { 1141 ret = max_segments; 1142 } 1143 1144 out: 1145 if (sysfd != -1) { 1146 close(sysfd); 1147 } 1148 g_free(sysfspath); 1149 return ret; 1150 #else 1151 return -ENOTSUP; 1152 #endif 1153 } 1154 1155 static void raw_refresh_limits(BlockDriverState *bs, Error **errp) 1156 { 1157 BDRVRawState *s = bs->opaque; 1158 1159 if (bs->sg) { 1160 int ret = sg_get_max_transfer_length(s->fd); 1161 1162 if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) { 1163 bs->bl.max_transfer = pow2floor(ret); 1164 } 1165 1166 ret = sg_get_max_segments(s->fd); 1167 if (ret > 0) { 1168 bs->bl.max_transfer = MIN(bs->bl.max_transfer, 1169 ret * qemu_real_host_page_size); 1170 } 1171 } 1172 1173 raw_probe_alignment(bs, s->fd, errp); 1174 bs->bl.min_mem_alignment = s->buf_align; 1175 bs->bl.opt_mem_alignment = MAX(s->buf_align, qemu_real_host_page_size); 1176 } 1177 1178 static int check_for_dasd(int fd) 1179 { 1180 #ifdef BIODASDINFO2 1181 struct dasd_information2_t info = {0}; 1182 1183 return ioctl(fd, BIODASDINFO2, &info); 1184 #else 1185 return -1; 1186 #endif 1187 } 1188 1189 /** 1190 * Try to get @bs's logical and physical block size. 1191 * On success, store them in @bsz and return zero. 1192 * On failure, return negative errno. 1193 */ 1194 static int hdev_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz) 1195 { 1196 BDRVRawState *s = bs->opaque; 1197 int ret; 1198 1199 /* If DASD, get blocksizes */ 1200 if (check_for_dasd(s->fd) < 0) { 1201 return -ENOTSUP; 1202 } 1203 ret = probe_logical_blocksize(s->fd, &bsz->log); 1204 if (ret < 0) { 1205 return ret; 1206 } 1207 return probe_physical_blocksize(s->fd, &bsz->phys); 1208 } 1209 1210 /** 1211 * Try to get @bs's geometry: cyls, heads, sectors. 1212 * On success, store them in @geo and return 0. 1213 * On failure return -errno. 1214 * (Allows block driver to assign default geometry values that guest sees) 1215 */ 1216 #ifdef __linux__ 1217 static int hdev_probe_geometry(BlockDriverState *bs, HDGeometry *geo) 1218 { 1219 BDRVRawState *s = bs->opaque; 1220 struct hd_geometry ioctl_geo = {0}; 1221 1222 /* If DASD, get its geometry */ 1223 if (check_for_dasd(s->fd) < 0) { 1224 return -ENOTSUP; 1225 } 1226 if (ioctl(s->fd, HDIO_GETGEO, &ioctl_geo) < 0) { 1227 return -errno; 1228 } 1229 /* HDIO_GETGEO may return success even though geo contains zeros 1230 (e.g. certain multipath setups) */ 1231 if (!ioctl_geo.heads || !ioctl_geo.sectors || !ioctl_geo.cylinders) { 1232 return -ENOTSUP; 1233 } 1234 /* Do not return a geometry for partition */ 1235 if (ioctl_geo.start != 0) { 1236 return -ENOTSUP; 1237 } 1238 geo->heads = ioctl_geo.heads; 1239 geo->sectors = ioctl_geo.sectors; 1240 geo->cylinders = ioctl_geo.cylinders; 1241 1242 return 0; 1243 } 1244 #else /* __linux__ */ 1245 static int hdev_probe_geometry(BlockDriverState *bs, HDGeometry *geo) 1246 { 1247 return -ENOTSUP; 1248 } 1249 #endif 1250 1251 #if defined(__linux__) 1252 static int handle_aiocb_ioctl(void *opaque) 1253 { 1254 RawPosixAIOData *aiocb = opaque; 1255 int ret; 1256 1257 ret = ioctl(aiocb->aio_fildes, aiocb->ioctl.cmd, aiocb->ioctl.buf); 1258 if (ret == -1) { 1259 return -errno; 1260 } 1261 1262 return 0; 1263 } 1264 #endif /* linux */ 1265 1266 static int handle_aiocb_flush(void *opaque) 1267 { 1268 RawPosixAIOData *aiocb = opaque; 1269 BDRVRawState *s = aiocb->bs->opaque; 1270 int ret; 1271 1272 if (s->page_cache_inconsistent) { 1273 return -EIO; 1274 } 1275 1276 ret = qemu_fdatasync(aiocb->aio_fildes); 1277 if (ret == -1) { 1278 /* There is no clear definition of the semantics of a failing fsync(), 1279 * so we may have to assume the worst. The sad truth is that this 1280 * assumption is correct for Linux. Some pages are now probably marked 1281 * clean in the page cache even though they are inconsistent with the 1282 * on-disk contents. The next fdatasync() call would succeed, but no 1283 * further writeback attempt will be made. We can't get back to a state 1284 * in which we know what is on disk (we would have to rewrite 1285 * everything that was touched since the last fdatasync() at least), so 1286 * make bdrv_flush() fail permanently. Given that the behaviour isn't 1287 * really defined, I have little hope that other OSes are doing better. 1288 * 1289 * Obviously, this doesn't affect O_DIRECT, which bypasses the page 1290 * cache. */ 1291 if ((s->open_flags & O_DIRECT) == 0) { 1292 s->page_cache_inconsistent = true; 1293 } 1294 return -errno; 1295 } 1296 return 0; 1297 } 1298 1299 #ifdef CONFIG_PREADV 1300 1301 static bool preadv_present = true; 1302 1303 static ssize_t 1304 qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset) 1305 { 1306 return preadv(fd, iov, nr_iov, offset); 1307 } 1308 1309 static ssize_t 1310 qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset) 1311 { 1312 return pwritev(fd, iov, nr_iov, offset); 1313 } 1314 1315 #else 1316 1317 static bool preadv_present = false; 1318 1319 static ssize_t 1320 qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset) 1321 { 1322 return -ENOSYS; 1323 } 1324 1325 static ssize_t 1326 qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset) 1327 { 1328 return -ENOSYS; 1329 } 1330 1331 #endif 1332 1333 static ssize_t handle_aiocb_rw_vector(RawPosixAIOData *aiocb) 1334 { 1335 ssize_t len; 1336 1337 do { 1338 if (aiocb->aio_type & QEMU_AIO_WRITE) 1339 len = qemu_pwritev(aiocb->aio_fildes, 1340 aiocb->io.iov, 1341 aiocb->io.niov, 1342 aiocb->aio_offset); 1343 else 1344 len = qemu_preadv(aiocb->aio_fildes, 1345 aiocb->io.iov, 1346 aiocb->io.niov, 1347 aiocb->aio_offset); 1348 } while (len == -1 && errno == EINTR); 1349 1350 if (len == -1) { 1351 return -errno; 1352 } 1353 return len; 1354 } 1355 1356 /* 1357 * Read/writes the data to/from a given linear buffer. 1358 * 1359 * Returns the number of bytes handles or -errno in case of an error. Short 1360 * reads are only returned if the end of the file is reached. 1361 */ 1362 static ssize_t handle_aiocb_rw_linear(RawPosixAIOData *aiocb, char *buf) 1363 { 1364 ssize_t offset = 0; 1365 ssize_t len; 1366 1367 while (offset < aiocb->aio_nbytes) { 1368 if (aiocb->aio_type & QEMU_AIO_WRITE) { 1369 len = pwrite(aiocb->aio_fildes, 1370 (const char *)buf + offset, 1371 aiocb->aio_nbytes - offset, 1372 aiocb->aio_offset + offset); 1373 } else { 1374 len = pread(aiocb->aio_fildes, 1375 buf + offset, 1376 aiocb->aio_nbytes - offset, 1377 aiocb->aio_offset + offset); 1378 } 1379 if (len == -1 && errno == EINTR) { 1380 continue; 1381 } else if (len == -1 && errno == EINVAL && 1382 (aiocb->bs->open_flags & BDRV_O_NOCACHE) && 1383 !(aiocb->aio_type & QEMU_AIO_WRITE) && 1384 offset > 0) { 1385 /* O_DIRECT pread() may fail with EINVAL when offset is unaligned 1386 * after a short read. Assume that O_DIRECT short reads only occur 1387 * at EOF. Therefore this is a short read, not an I/O error. 1388 */ 1389 break; 1390 } else if (len == -1) { 1391 offset = -errno; 1392 break; 1393 } else if (len == 0) { 1394 break; 1395 } 1396 offset += len; 1397 } 1398 1399 return offset; 1400 } 1401 1402 static int handle_aiocb_rw(void *opaque) 1403 { 1404 RawPosixAIOData *aiocb = opaque; 1405 ssize_t nbytes; 1406 char *buf; 1407 1408 if (!(aiocb->aio_type & QEMU_AIO_MISALIGNED)) { 1409 /* 1410 * If there is just a single buffer, and it is properly aligned 1411 * we can just use plain pread/pwrite without any problems. 1412 */ 1413 if (aiocb->io.niov == 1) { 1414 nbytes = handle_aiocb_rw_linear(aiocb, aiocb->io.iov->iov_base); 1415 goto out; 1416 } 1417 /* 1418 * We have more than one iovec, and all are properly aligned. 1419 * 1420 * Try preadv/pwritev first and fall back to linearizing the 1421 * buffer if it's not supported. 1422 */ 1423 if (preadv_present) { 1424 nbytes = handle_aiocb_rw_vector(aiocb); 1425 if (nbytes == aiocb->aio_nbytes || 1426 (nbytes < 0 && nbytes != -ENOSYS)) { 1427 goto out; 1428 } 1429 preadv_present = false; 1430 } 1431 1432 /* 1433 * XXX(hch): short read/write. no easy way to handle the reminder 1434 * using these interfaces. For now retry using plain 1435 * pread/pwrite? 1436 */ 1437 } 1438 1439 /* 1440 * Ok, we have to do it the hard way, copy all segments into 1441 * a single aligned buffer. 1442 */ 1443 buf = qemu_try_blockalign(aiocb->bs, aiocb->aio_nbytes); 1444 if (buf == NULL) { 1445 nbytes = -ENOMEM; 1446 goto out; 1447 } 1448 1449 if (aiocb->aio_type & QEMU_AIO_WRITE) { 1450 char *p = buf; 1451 int i; 1452 1453 for (i = 0; i < aiocb->io.niov; ++i) { 1454 memcpy(p, aiocb->io.iov[i].iov_base, aiocb->io.iov[i].iov_len); 1455 p += aiocb->io.iov[i].iov_len; 1456 } 1457 assert(p - buf == aiocb->aio_nbytes); 1458 } 1459 1460 nbytes = handle_aiocb_rw_linear(aiocb, buf); 1461 if (!(aiocb->aio_type & QEMU_AIO_WRITE)) { 1462 char *p = buf; 1463 size_t count = aiocb->aio_nbytes, copy; 1464 int i; 1465 1466 for (i = 0; i < aiocb->io.niov && count; ++i) { 1467 copy = count; 1468 if (copy > aiocb->io.iov[i].iov_len) { 1469 copy = aiocb->io.iov[i].iov_len; 1470 } 1471 memcpy(aiocb->io.iov[i].iov_base, p, copy); 1472 assert(count >= copy); 1473 p += copy; 1474 count -= copy; 1475 } 1476 assert(count == 0); 1477 } 1478 qemu_vfree(buf); 1479 1480 out: 1481 if (nbytes == aiocb->aio_nbytes) { 1482 return 0; 1483 } else if (nbytes >= 0 && nbytes < aiocb->aio_nbytes) { 1484 if (aiocb->aio_type & QEMU_AIO_WRITE) { 1485 return -EINVAL; 1486 } else { 1487 iov_memset(aiocb->io.iov, aiocb->io.niov, nbytes, 1488 0, aiocb->aio_nbytes - nbytes); 1489 return 0; 1490 } 1491 } else { 1492 assert(nbytes < 0); 1493 return nbytes; 1494 } 1495 } 1496 1497 static int translate_err(int err) 1498 { 1499 if (err == -ENODEV || err == -ENOSYS || err == -EOPNOTSUPP || 1500 err == -ENOTTY) { 1501 err = -ENOTSUP; 1502 } 1503 return err; 1504 } 1505 1506 #ifdef CONFIG_FALLOCATE 1507 static int do_fallocate(int fd, int mode, off_t offset, off_t len) 1508 { 1509 do { 1510 if (fallocate(fd, mode, offset, len) == 0) { 1511 return 0; 1512 } 1513 } while (errno == EINTR); 1514 return translate_err(-errno); 1515 } 1516 #endif 1517 1518 static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb) 1519 { 1520 int ret = -ENOTSUP; 1521 BDRVRawState *s = aiocb->bs->opaque; 1522 1523 if (!s->has_write_zeroes) { 1524 return -ENOTSUP; 1525 } 1526 1527 #ifdef BLKZEROOUT 1528 /* The BLKZEROOUT implementation in the kernel doesn't set 1529 * BLKDEV_ZERO_NOFALLBACK, so we can't call this if we have to avoid slow 1530 * fallbacks. */ 1531 if (!(aiocb->aio_type & QEMU_AIO_NO_FALLBACK)) { 1532 do { 1533 uint64_t range[2] = { aiocb->aio_offset, aiocb->aio_nbytes }; 1534 if (ioctl(aiocb->aio_fildes, BLKZEROOUT, range) == 0) { 1535 return 0; 1536 } 1537 } while (errno == EINTR); 1538 1539 ret = translate_err(-errno); 1540 if (ret == -ENOTSUP) { 1541 s->has_write_zeroes = false; 1542 } 1543 } 1544 #endif 1545 1546 return ret; 1547 } 1548 1549 static int handle_aiocb_write_zeroes(void *opaque) 1550 { 1551 RawPosixAIOData *aiocb = opaque; 1552 #ifdef CONFIG_FALLOCATE 1553 BDRVRawState *s = aiocb->bs->opaque; 1554 int64_t len; 1555 #endif 1556 1557 if (aiocb->aio_type & QEMU_AIO_BLKDEV) { 1558 return handle_aiocb_write_zeroes_block(aiocb); 1559 } 1560 1561 #ifdef CONFIG_FALLOCATE_ZERO_RANGE 1562 if (s->has_write_zeroes) { 1563 int ret = do_fallocate(s->fd, FALLOC_FL_ZERO_RANGE, 1564 aiocb->aio_offset, aiocb->aio_nbytes); 1565 if (ret == -EINVAL) { 1566 /* 1567 * Allow falling back to pwrite for file systems that 1568 * do not support fallocate() for an unaligned byte range. 1569 */ 1570 return -ENOTSUP; 1571 } 1572 if (ret == 0 || ret != -ENOTSUP) { 1573 return ret; 1574 } 1575 s->has_write_zeroes = false; 1576 } 1577 #endif 1578 1579 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE 1580 if (s->has_discard && s->has_fallocate) { 1581 int ret = do_fallocate(s->fd, 1582 FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 1583 aiocb->aio_offset, aiocb->aio_nbytes); 1584 if (ret == 0) { 1585 ret = do_fallocate(s->fd, 0, aiocb->aio_offset, aiocb->aio_nbytes); 1586 if (ret == 0 || ret != -ENOTSUP) { 1587 return ret; 1588 } 1589 s->has_fallocate = false; 1590 } else if (ret != -ENOTSUP) { 1591 return ret; 1592 } else { 1593 s->has_discard = false; 1594 } 1595 } 1596 #endif 1597 1598 #ifdef CONFIG_FALLOCATE 1599 /* Last resort: we are trying to extend the file with zeroed data. This 1600 * can be done via fallocate(fd, 0) */ 1601 len = bdrv_getlength(aiocb->bs); 1602 if (s->has_fallocate && len >= 0 && aiocb->aio_offset >= len) { 1603 int ret = do_fallocate(s->fd, 0, aiocb->aio_offset, aiocb->aio_nbytes); 1604 if (ret == 0 || ret != -ENOTSUP) { 1605 return ret; 1606 } 1607 s->has_fallocate = false; 1608 } 1609 #endif 1610 1611 return -ENOTSUP; 1612 } 1613 1614 static int handle_aiocb_write_zeroes_unmap(void *opaque) 1615 { 1616 RawPosixAIOData *aiocb = opaque; 1617 BDRVRawState *s G_GNUC_UNUSED = aiocb->bs->opaque; 1618 1619 /* First try to write zeros and unmap at the same time */ 1620 1621 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE 1622 int ret = do_fallocate(s->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 1623 aiocb->aio_offset, aiocb->aio_nbytes); 1624 if (ret != -ENOTSUP) { 1625 return ret; 1626 } 1627 #endif 1628 1629 /* If we couldn't manage to unmap while guaranteed that the area reads as 1630 * all-zero afterwards, just write zeroes without unmapping */ 1631 return handle_aiocb_write_zeroes(aiocb); 1632 } 1633 1634 #ifndef HAVE_COPY_FILE_RANGE 1635 static off_t copy_file_range(int in_fd, off_t *in_off, int out_fd, 1636 off_t *out_off, size_t len, unsigned int flags) 1637 { 1638 #ifdef __NR_copy_file_range 1639 return syscall(__NR_copy_file_range, in_fd, in_off, out_fd, 1640 out_off, len, flags); 1641 #else 1642 errno = ENOSYS; 1643 return -1; 1644 #endif 1645 } 1646 #endif 1647 1648 static int handle_aiocb_copy_range(void *opaque) 1649 { 1650 RawPosixAIOData *aiocb = opaque; 1651 uint64_t bytes = aiocb->aio_nbytes; 1652 off_t in_off = aiocb->aio_offset; 1653 off_t out_off = aiocb->copy_range.aio_offset2; 1654 1655 while (bytes) { 1656 ssize_t ret = copy_file_range(aiocb->aio_fildes, &in_off, 1657 aiocb->copy_range.aio_fd2, &out_off, 1658 bytes, 0); 1659 trace_file_copy_file_range(aiocb->bs, aiocb->aio_fildes, in_off, 1660 aiocb->copy_range.aio_fd2, out_off, bytes, 1661 0, ret); 1662 if (ret == 0) { 1663 /* No progress (e.g. when beyond EOF), let the caller fall back to 1664 * buffer I/O. */ 1665 return -ENOSPC; 1666 } 1667 if (ret < 0) { 1668 switch (errno) { 1669 case ENOSYS: 1670 return -ENOTSUP; 1671 case EINTR: 1672 continue; 1673 default: 1674 return -errno; 1675 } 1676 } 1677 bytes -= ret; 1678 } 1679 return 0; 1680 } 1681 1682 static int handle_aiocb_discard(void *opaque) 1683 { 1684 RawPosixAIOData *aiocb = opaque; 1685 int ret = -EOPNOTSUPP; 1686 BDRVRawState *s = aiocb->bs->opaque; 1687 1688 if (!s->has_discard) { 1689 return -ENOTSUP; 1690 } 1691 1692 if (aiocb->aio_type & QEMU_AIO_BLKDEV) { 1693 #ifdef BLKDISCARD 1694 do { 1695 uint64_t range[2] = { aiocb->aio_offset, aiocb->aio_nbytes }; 1696 if (ioctl(aiocb->aio_fildes, BLKDISCARD, range) == 0) { 1697 return 0; 1698 } 1699 } while (errno == EINTR); 1700 1701 ret = -errno; 1702 #endif 1703 } else { 1704 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE 1705 ret = do_fallocate(s->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 1706 aiocb->aio_offset, aiocb->aio_nbytes); 1707 #endif 1708 } 1709 1710 ret = translate_err(ret); 1711 if (ret == -ENOTSUP) { 1712 s->has_discard = false; 1713 } 1714 return ret; 1715 } 1716 1717 /* 1718 * Help alignment probing by allocating the first block. 1719 * 1720 * When reading with direct I/O from unallocated area on Gluster backed by XFS, 1721 * reading succeeds regardless of request length. In this case we fallback to 1722 * safe alignment which is not optimal. Allocating the first block avoids this 1723 * fallback. 1724 * 1725 * fd may be opened with O_DIRECT, but we don't know the buffer alignment or 1726 * request alignment, so we use safe values. 1727 * 1728 * Returns: 0 on success, -errno on failure. Since this is an optimization, 1729 * caller may ignore failures. 1730 */ 1731 static int allocate_first_block(int fd, size_t max_size) 1732 { 1733 size_t write_size = (max_size < MAX_BLOCKSIZE) 1734 ? BDRV_SECTOR_SIZE 1735 : MAX_BLOCKSIZE; 1736 size_t max_align = MAX(MAX_BLOCKSIZE, qemu_real_host_page_size); 1737 void *buf; 1738 ssize_t n; 1739 int ret; 1740 1741 buf = qemu_memalign(max_align, write_size); 1742 memset(buf, 0, write_size); 1743 1744 do { 1745 n = pwrite(fd, buf, write_size, 0); 1746 } while (n == -1 && errno == EINTR); 1747 1748 ret = (n == -1) ? -errno : 0; 1749 1750 qemu_vfree(buf); 1751 return ret; 1752 } 1753 1754 static int handle_aiocb_truncate(void *opaque) 1755 { 1756 RawPosixAIOData *aiocb = opaque; 1757 int result = 0; 1758 int64_t current_length = 0; 1759 char *buf = NULL; 1760 struct stat st; 1761 int fd = aiocb->aio_fildes; 1762 int64_t offset = aiocb->aio_offset; 1763 PreallocMode prealloc = aiocb->truncate.prealloc; 1764 Error **errp = aiocb->truncate.errp; 1765 1766 if (fstat(fd, &st) < 0) { 1767 result = -errno; 1768 error_setg_errno(errp, -result, "Could not stat file"); 1769 return result; 1770 } 1771 1772 current_length = st.st_size; 1773 if (current_length > offset && prealloc != PREALLOC_MODE_OFF) { 1774 error_setg(errp, "Cannot use preallocation for shrinking files"); 1775 return -ENOTSUP; 1776 } 1777 1778 switch (prealloc) { 1779 #ifdef CONFIG_POSIX_FALLOCATE 1780 case PREALLOC_MODE_FALLOC: 1781 /* 1782 * Truncating before posix_fallocate() makes it about twice slower on 1783 * file systems that do not support fallocate(), trying to check if a 1784 * block is allocated before allocating it, so don't do that here. 1785 */ 1786 if (offset != current_length) { 1787 result = -posix_fallocate(fd, current_length, 1788 offset - current_length); 1789 if (result != 0) { 1790 /* posix_fallocate() doesn't set errno. */ 1791 error_setg_errno(errp, -result, 1792 "Could not preallocate new data"); 1793 } else if (current_length == 0) { 1794 /* 1795 * posix_fallocate() uses fallocate() if the filesystem 1796 * supports it, or fallback to manually writing zeroes. If 1797 * fallocate() was used, unaligned reads from the fallocated 1798 * area in raw_probe_alignment() will succeed, hence we need to 1799 * allocate the first block. 1800 * 1801 * Optimize future alignment probing; ignore failures. 1802 */ 1803 allocate_first_block(fd, offset); 1804 } 1805 } else { 1806 result = 0; 1807 } 1808 goto out; 1809 #endif 1810 case PREALLOC_MODE_FULL: 1811 { 1812 int64_t num = 0, left = offset - current_length; 1813 off_t seek_result; 1814 1815 /* 1816 * Knowing the final size from the beginning could allow the file 1817 * system driver to do less allocations and possibly avoid 1818 * fragmentation of the file. 1819 */ 1820 if (ftruncate(fd, offset) != 0) { 1821 result = -errno; 1822 error_setg_errno(errp, -result, "Could not resize file"); 1823 goto out; 1824 } 1825 1826 buf = g_malloc0(65536); 1827 1828 seek_result = lseek(fd, current_length, SEEK_SET); 1829 if (seek_result < 0) { 1830 result = -errno; 1831 error_setg_errno(errp, -result, 1832 "Failed to seek to the old end of file"); 1833 goto out; 1834 } 1835 1836 while (left > 0) { 1837 num = MIN(left, 65536); 1838 result = write(fd, buf, num); 1839 if (result < 0) { 1840 if (errno == EINTR) { 1841 continue; 1842 } 1843 result = -errno; 1844 error_setg_errno(errp, -result, 1845 "Could not write zeros for preallocation"); 1846 goto out; 1847 } 1848 left -= result; 1849 } 1850 if (result >= 0) { 1851 result = fsync(fd); 1852 if (result < 0) { 1853 result = -errno; 1854 error_setg_errno(errp, -result, 1855 "Could not flush file to disk"); 1856 goto out; 1857 } 1858 } 1859 goto out; 1860 } 1861 case PREALLOC_MODE_OFF: 1862 if (ftruncate(fd, offset) != 0) { 1863 result = -errno; 1864 error_setg_errno(errp, -result, "Could not resize file"); 1865 } else if (current_length == 0 && offset > current_length) { 1866 /* Optimize future alignment probing; ignore failures. */ 1867 allocate_first_block(fd, offset); 1868 } 1869 return result; 1870 default: 1871 result = -ENOTSUP; 1872 error_setg(errp, "Unsupported preallocation mode: %s", 1873 PreallocMode_str(prealloc)); 1874 return result; 1875 } 1876 1877 out: 1878 if (result < 0) { 1879 if (ftruncate(fd, current_length) < 0) { 1880 error_report("Failed to restore old file length: %s", 1881 strerror(errno)); 1882 } 1883 } 1884 1885 g_free(buf); 1886 return result; 1887 } 1888 1889 static int coroutine_fn raw_thread_pool_submit(BlockDriverState *bs, 1890 ThreadPoolFunc func, void *arg) 1891 { 1892 /* @bs can be NULL, bdrv_get_aio_context() returns the main context then */ 1893 ThreadPool *pool = aio_get_thread_pool(bdrv_get_aio_context(bs)); 1894 return thread_pool_submit_co(pool, func, arg); 1895 } 1896 1897 static int coroutine_fn raw_co_prw(BlockDriverState *bs, uint64_t offset, 1898 uint64_t bytes, QEMUIOVector *qiov, int type) 1899 { 1900 BDRVRawState *s = bs->opaque; 1901 RawPosixAIOData acb; 1902 1903 if (fd_open(bs) < 0) 1904 return -EIO; 1905 1906 /* 1907 * When using O_DIRECT, the request must be aligned to be able to use 1908 * either libaio or io_uring interface. If not fail back to regular thread 1909 * pool read/write code which emulates this for us if we 1910 * set QEMU_AIO_MISALIGNED. 1911 */ 1912 if (s->needs_alignment && !bdrv_qiov_is_aligned(bs, qiov)) { 1913 type |= QEMU_AIO_MISALIGNED; 1914 #ifdef CONFIG_LINUX_IO_URING 1915 } else if (s->use_linux_io_uring) { 1916 LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs)); 1917 assert(qiov->size == bytes); 1918 return luring_co_submit(bs, aio, s->fd, offset, qiov, type); 1919 #endif 1920 #ifdef CONFIG_LINUX_AIO 1921 } else if (s->use_linux_aio) { 1922 LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs)); 1923 assert(qiov->size == bytes); 1924 return laio_co_submit(bs, aio, s->fd, offset, qiov, type); 1925 #endif 1926 } 1927 1928 acb = (RawPosixAIOData) { 1929 .bs = bs, 1930 .aio_fildes = s->fd, 1931 .aio_type = type, 1932 .aio_offset = offset, 1933 .aio_nbytes = bytes, 1934 .io = { 1935 .iov = qiov->iov, 1936 .niov = qiov->niov, 1937 }, 1938 }; 1939 1940 assert(qiov->size == bytes); 1941 return raw_thread_pool_submit(bs, handle_aiocb_rw, &acb); 1942 } 1943 1944 static int coroutine_fn raw_co_preadv(BlockDriverState *bs, uint64_t offset, 1945 uint64_t bytes, QEMUIOVector *qiov, 1946 int flags) 1947 { 1948 return raw_co_prw(bs, offset, bytes, qiov, QEMU_AIO_READ); 1949 } 1950 1951 static int coroutine_fn raw_co_pwritev(BlockDriverState *bs, uint64_t offset, 1952 uint64_t bytes, QEMUIOVector *qiov, 1953 int flags) 1954 { 1955 assert(flags == 0); 1956 return raw_co_prw(bs, offset, bytes, qiov, QEMU_AIO_WRITE); 1957 } 1958 1959 static void raw_aio_plug(BlockDriverState *bs) 1960 { 1961 BDRVRawState __attribute__((unused)) *s = bs->opaque; 1962 #ifdef CONFIG_LINUX_AIO 1963 if (s->use_linux_aio) { 1964 LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs)); 1965 laio_io_plug(bs, aio); 1966 } 1967 #endif 1968 #ifdef CONFIG_LINUX_IO_URING 1969 if (s->use_linux_io_uring) { 1970 LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs)); 1971 luring_io_plug(bs, aio); 1972 } 1973 #endif 1974 } 1975 1976 static void raw_aio_unplug(BlockDriverState *bs) 1977 { 1978 BDRVRawState __attribute__((unused)) *s = bs->opaque; 1979 #ifdef CONFIG_LINUX_AIO 1980 if (s->use_linux_aio) { 1981 LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs)); 1982 laio_io_unplug(bs, aio); 1983 } 1984 #endif 1985 #ifdef CONFIG_LINUX_IO_URING 1986 if (s->use_linux_io_uring) { 1987 LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs)); 1988 luring_io_unplug(bs, aio); 1989 } 1990 #endif 1991 } 1992 1993 static int raw_co_flush_to_disk(BlockDriverState *bs) 1994 { 1995 BDRVRawState *s = bs->opaque; 1996 RawPosixAIOData acb; 1997 int ret; 1998 1999 ret = fd_open(bs); 2000 if (ret < 0) { 2001 return ret; 2002 } 2003 2004 acb = (RawPosixAIOData) { 2005 .bs = bs, 2006 .aio_fildes = s->fd, 2007 .aio_type = QEMU_AIO_FLUSH, 2008 }; 2009 2010 #ifdef CONFIG_LINUX_IO_URING 2011 if (s->use_linux_io_uring) { 2012 LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs)); 2013 return luring_co_submit(bs, aio, s->fd, 0, NULL, QEMU_AIO_FLUSH); 2014 } 2015 #endif 2016 return raw_thread_pool_submit(bs, handle_aiocb_flush, &acb); 2017 } 2018 2019 static void raw_aio_attach_aio_context(BlockDriverState *bs, 2020 AioContext *new_context) 2021 { 2022 BDRVRawState __attribute__((unused)) *s = bs->opaque; 2023 #ifdef CONFIG_LINUX_AIO 2024 if (s->use_linux_aio) { 2025 Error *local_err = NULL; 2026 if (!aio_setup_linux_aio(new_context, &local_err)) { 2027 error_reportf_err(local_err, "Unable to use native AIO, " 2028 "falling back to thread pool: "); 2029 s->use_linux_aio = false; 2030 } 2031 } 2032 #endif 2033 #ifdef CONFIG_LINUX_IO_URING 2034 if (s->use_linux_io_uring) { 2035 Error *local_err; 2036 if (!aio_setup_linux_io_uring(new_context, &local_err)) { 2037 error_reportf_err(local_err, "Unable to use linux io_uring, " 2038 "falling back to thread pool: "); 2039 s->use_linux_io_uring = false; 2040 } 2041 } 2042 #endif 2043 } 2044 2045 static void raw_close(BlockDriverState *bs) 2046 { 2047 BDRVRawState *s = bs->opaque; 2048 2049 if (s->fd >= 0) { 2050 qemu_close(s->fd); 2051 s->fd = -1; 2052 } 2053 } 2054 2055 /** 2056 * Truncates the given regular file @fd to @offset and, when growing, fills the 2057 * new space according to @prealloc. 2058 * 2059 * Returns: 0 on success, -errno on failure. 2060 */ 2061 static int coroutine_fn 2062 raw_regular_truncate(BlockDriverState *bs, int fd, int64_t offset, 2063 PreallocMode prealloc, Error **errp) 2064 { 2065 RawPosixAIOData acb; 2066 2067 acb = (RawPosixAIOData) { 2068 .bs = bs, 2069 .aio_fildes = fd, 2070 .aio_type = QEMU_AIO_TRUNCATE, 2071 .aio_offset = offset, 2072 .truncate = { 2073 .prealloc = prealloc, 2074 .errp = errp, 2075 }, 2076 }; 2077 2078 return raw_thread_pool_submit(bs, handle_aiocb_truncate, &acb); 2079 } 2080 2081 static int coroutine_fn raw_co_truncate(BlockDriverState *bs, int64_t offset, 2082 bool exact, PreallocMode prealloc, 2083 BdrvRequestFlags flags, Error **errp) 2084 { 2085 BDRVRawState *s = bs->opaque; 2086 struct stat st; 2087 int ret; 2088 2089 if (fstat(s->fd, &st)) { 2090 ret = -errno; 2091 error_setg_errno(errp, -ret, "Failed to fstat() the file"); 2092 return ret; 2093 } 2094 2095 if (S_ISREG(st.st_mode)) { 2096 /* Always resizes to the exact @offset */ 2097 return raw_regular_truncate(bs, s->fd, offset, prealloc, errp); 2098 } 2099 2100 if (prealloc != PREALLOC_MODE_OFF) { 2101 error_setg(errp, "Preallocation mode '%s' unsupported for this " 2102 "non-regular file", PreallocMode_str(prealloc)); 2103 return -ENOTSUP; 2104 } 2105 2106 if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) { 2107 int64_t cur_length = raw_getlength(bs); 2108 2109 if (offset != cur_length && exact) { 2110 error_setg(errp, "Cannot resize device files"); 2111 return -ENOTSUP; 2112 } else if (offset > cur_length) { 2113 error_setg(errp, "Cannot grow device files"); 2114 return -EINVAL; 2115 } 2116 } else { 2117 error_setg(errp, "Resizing this file is not supported"); 2118 return -ENOTSUP; 2119 } 2120 2121 return 0; 2122 } 2123 2124 #ifdef __OpenBSD__ 2125 static int64_t raw_getlength(BlockDriverState *bs) 2126 { 2127 BDRVRawState *s = bs->opaque; 2128 int fd = s->fd; 2129 struct stat st; 2130 2131 if (fstat(fd, &st)) 2132 return -errno; 2133 if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) { 2134 struct disklabel dl; 2135 2136 if (ioctl(fd, DIOCGDINFO, &dl)) 2137 return -errno; 2138 return (uint64_t)dl.d_secsize * 2139 dl.d_partitions[DISKPART(st.st_rdev)].p_size; 2140 } else 2141 return st.st_size; 2142 } 2143 #elif defined(__NetBSD__) 2144 static int64_t raw_getlength(BlockDriverState *bs) 2145 { 2146 BDRVRawState *s = bs->opaque; 2147 int fd = s->fd; 2148 struct stat st; 2149 2150 if (fstat(fd, &st)) 2151 return -errno; 2152 if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) { 2153 struct dkwedge_info dkw; 2154 2155 if (ioctl(fd, DIOCGWEDGEINFO, &dkw) != -1) { 2156 return dkw.dkw_size * 512; 2157 } else { 2158 struct disklabel dl; 2159 2160 if (ioctl(fd, DIOCGDINFO, &dl)) 2161 return -errno; 2162 return (uint64_t)dl.d_secsize * 2163 dl.d_partitions[DISKPART(st.st_rdev)].p_size; 2164 } 2165 } else 2166 return st.st_size; 2167 } 2168 #elif defined(__sun__) 2169 static int64_t raw_getlength(BlockDriverState *bs) 2170 { 2171 BDRVRawState *s = bs->opaque; 2172 struct dk_minfo minfo; 2173 int ret; 2174 int64_t size; 2175 2176 ret = fd_open(bs); 2177 if (ret < 0) { 2178 return ret; 2179 } 2180 2181 /* 2182 * Use the DKIOCGMEDIAINFO ioctl to read the size. 2183 */ 2184 ret = ioctl(s->fd, DKIOCGMEDIAINFO, &minfo); 2185 if (ret != -1) { 2186 return minfo.dki_lbsize * minfo.dki_capacity; 2187 } 2188 2189 /* 2190 * There are reports that lseek on some devices fails, but 2191 * irc discussion said that contingency on contingency was overkill. 2192 */ 2193 size = lseek(s->fd, 0, SEEK_END); 2194 if (size < 0) { 2195 return -errno; 2196 } 2197 return size; 2198 } 2199 #elif defined(CONFIG_BSD) 2200 static int64_t raw_getlength(BlockDriverState *bs) 2201 { 2202 BDRVRawState *s = bs->opaque; 2203 int fd = s->fd; 2204 int64_t size; 2205 struct stat sb; 2206 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__) 2207 int reopened = 0; 2208 #endif 2209 int ret; 2210 2211 ret = fd_open(bs); 2212 if (ret < 0) 2213 return ret; 2214 2215 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__) 2216 again: 2217 #endif 2218 if (!fstat(fd, &sb) && (S_IFCHR & sb.st_mode)) { 2219 #ifdef DIOCGMEDIASIZE 2220 if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size)) 2221 #elif defined(DIOCGPART) 2222 { 2223 struct partinfo pi; 2224 if (ioctl(fd, DIOCGPART, &pi) == 0) 2225 size = pi.media_size; 2226 else 2227 size = 0; 2228 } 2229 if (size == 0) 2230 #endif 2231 #if defined(__APPLE__) && defined(__MACH__) 2232 { 2233 uint64_t sectors = 0; 2234 uint32_t sector_size = 0; 2235 2236 if (ioctl(fd, DKIOCGETBLOCKCOUNT, §ors) == 0 2237 && ioctl(fd, DKIOCGETBLOCKSIZE, §or_size) == 0) { 2238 size = sectors * sector_size; 2239 } else { 2240 size = lseek(fd, 0LL, SEEK_END); 2241 if (size < 0) { 2242 return -errno; 2243 } 2244 } 2245 } 2246 #else 2247 size = lseek(fd, 0LL, SEEK_END); 2248 if (size < 0) { 2249 return -errno; 2250 } 2251 #endif 2252 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) 2253 switch(s->type) { 2254 case FTYPE_CD: 2255 /* XXX FreeBSD acd returns UINT_MAX sectors for an empty drive */ 2256 if (size == 2048LL * (unsigned)-1) 2257 size = 0; 2258 /* XXX no disc? maybe we need to reopen... */ 2259 if (size <= 0 && !reopened && cdrom_reopen(bs) >= 0) { 2260 reopened = 1; 2261 goto again; 2262 } 2263 } 2264 #endif 2265 } else { 2266 size = lseek(fd, 0, SEEK_END); 2267 if (size < 0) { 2268 return -errno; 2269 } 2270 } 2271 return size; 2272 } 2273 #else 2274 static int64_t raw_getlength(BlockDriverState *bs) 2275 { 2276 BDRVRawState *s = bs->opaque; 2277 int ret; 2278 int64_t size; 2279 2280 ret = fd_open(bs); 2281 if (ret < 0) { 2282 return ret; 2283 } 2284 2285 size = lseek(s->fd, 0, SEEK_END); 2286 if (size < 0) { 2287 return -errno; 2288 } 2289 return size; 2290 } 2291 #endif 2292 2293 static int64_t raw_get_allocated_file_size(BlockDriverState *bs) 2294 { 2295 struct stat st; 2296 BDRVRawState *s = bs->opaque; 2297 2298 if (fstat(s->fd, &st) < 0) { 2299 return -errno; 2300 } 2301 return (int64_t)st.st_blocks * 512; 2302 } 2303 2304 static int coroutine_fn 2305 raw_co_create(BlockdevCreateOptions *options, Error **errp) 2306 { 2307 BlockdevCreateOptionsFile *file_opts; 2308 Error *local_err = NULL; 2309 int fd; 2310 uint64_t perm, shared; 2311 int result = 0; 2312 2313 /* Validate options and set default values */ 2314 assert(options->driver == BLOCKDEV_DRIVER_FILE); 2315 file_opts = &options->u.file; 2316 2317 if (!file_opts->has_nocow) { 2318 file_opts->nocow = false; 2319 } 2320 if (!file_opts->has_preallocation) { 2321 file_opts->preallocation = PREALLOC_MODE_OFF; 2322 } 2323 2324 /* Create file */ 2325 fd = qemu_open(file_opts->filename, O_RDWR | O_CREAT | O_BINARY, 0644); 2326 if (fd < 0) { 2327 result = -errno; 2328 error_setg_errno(errp, -result, "Could not create file"); 2329 goto out; 2330 } 2331 2332 /* Take permissions: We want to discard everything, so we need 2333 * BLK_PERM_WRITE; and truncation to the desired size requires 2334 * BLK_PERM_RESIZE. 2335 * On the other hand, we cannot share the RESIZE permission 2336 * because we promise that after this function, the file has the 2337 * size given in the options. If someone else were to resize it 2338 * concurrently, we could not guarantee that. 2339 * Note that after this function, we can no longer guarantee that 2340 * the file is not touched by a third party, so it may be resized 2341 * then. */ 2342 perm = BLK_PERM_WRITE | BLK_PERM_RESIZE; 2343 shared = BLK_PERM_ALL & ~BLK_PERM_RESIZE; 2344 2345 /* Step one: Take locks */ 2346 result = raw_apply_lock_bytes(NULL, fd, perm, ~shared, false, errp); 2347 if (result < 0) { 2348 goto out_close; 2349 } 2350 2351 /* Step two: Check that nobody else has taken conflicting locks */ 2352 result = raw_check_lock_bytes(fd, perm, shared, errp); 2353 if (result < 0) { 2354 error_append_hint(errp, 2355 "Is another process using the image [%s]?\n", 2356 file_opts->filename); 2357 goto out_unlock; 2358 } 2359 2360 /* Clear the file by truncating it to 0 */ 2361 result = raw_regular_truncate(NULL, fd, 0, PREALLOC_MODE_OFF, errp); 2362 if (result < 0) { 2363 goto out_unlock; 2364 } 2365 2366 if (file_opts->nocow) { 2367 #ifdef __linux__ 2368 /* Set NOCOW flag to solve performance issue on fs like btrfs. 2369 * This is an optimisation. The FS_IOC_SETFLAGS ioctl return value 2370 * will be ignored since any failure of this operation should not 2371 * block the left work. 2372 */ 2373 int attr; 2374 if (ioctl(fd, FS_IOC_GETFLAGS, &attr) == 0) { 2375 attr |= FS_NOCOW_FL; 2376 ioctl(fd, FS_IOC_SETFLAGS, &attr); 2377 } 2378 #endif 2379 } 2380 2381 /* Resize and potentially preallocate the file to the desired 2382 * final size */ 2383 result = raw_regular_truncate(NULL, fd, file_opts->size, 2384 file_opts->preallocation, errp); 2385 if (result < 0) { 2386 goto out_unlock; 2387 } 2388 2389 out_unlock: 2390 raw_apply_lock_bytes(NULL, fd, 0, 0, true, &local_err); 2391 if (local_err) { 2392 /* The above call should not fail, and if it does, that does 2393 * not mean the whole creation operation has failed. So 2394 * report it the user for their convenience, but do not report 2395 * it to the caller. */ 2396 warn_report_err(local_err); 2397 } 2398 2399 out_close: 2400 if (qemu_close(fd) != 0 && result == 0) { 2401 result = -errno; 2402 error_setg_errno(errp, -result, "Could not close the new file"); 2403 } 2404 out: 2405 return result; 2406 } 2407 2408 static int coroutine_fn raw_co_create_opts(BlockDriver *drv, 2409 const char *filename, 2410 QemuOpts *opts, 2411 Error **errp) 2412 { 2413 BlockdevCreateOptions options; 2414 int64_t total_size = 0; 2415 bool nocow = false; 2416 PreallocMode prealloc; 2417 char *buf = NULL; 2418 Error *local_err = NULL; 2419 2420 /* Skip file: protocol prefix */ 2421 strstart(filename, "file:", &filename); 2422 2423 /* Read out options */ 2424 total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 2425 BDRV_SECTOR_SIZE); 2426 nocow = qemu_opt_get_bool(opts, BLOCK_OPT_NOCOW, false); 2427 buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); 2428 prealloc = qapi_enum_parse(&PreallocMode_lookup, buf, 2429 PREALLOC_MODE_OFF, &local_err); 2430 g_free(buf); 2431 if (local_err) { 2432 error_propagate(errp, local_err); 2433 return -EINVAL; 2434 } 2435 2436 options = (BlockdevCreateOptions) { 2437 .driver = BLOCKDEV_DRIVER_FILE, 2438 .u.file = { 2439 .filename = (char *) filename, 2440 .size = total_size, 2441 .has_preallocation = true, 2442 .preallocation = prealloc, 2443 .has_nocow = true, 2444 .nocow = nocow, 2445 }, 2446 }; 2447 return raw_co_create(&options, errp); 2448 } 2449 2450 static int coroutine_fn raw_co_delete_file(BlockDriverState *bs, 2451 Error **errp) 2452 { 2453 struct stat st; 2454 int ret; 2455 2456 if (!(stat(bs->filename, &st) == 0) || !S_ISREG(st.st_mode)) { 2457 error_setg_errno(errp, ENOENT, "%s is not a regular file", 2458 bs->filename); 2459 return -ENOENT; 2460 } 2461 2462 ret = unlink(bs->filename); 2463 if (ret < 0) { 2464 ret = -errno; 2465 error_setg_errno(errp, -ret, "Error when deleting file %s", 2466 bs->filename); 2467 } 2468 2469 return ret; 2470 } 2471 2472 /* 2473 * Find allocation range in @bs around offset @start. 2474 * May change underlying file descriptor's file offset. 2475 * If @start is not in a hole, store @start in @data, and the 2476 * beginning of the next hole in @hole, and return 0. 2477 * If @start is in a non-trailing hole, store @start in @hole and the 2478 * beginning of the next non-hole in @data, and return 0. 2479 * If @start is in a trailing hole or beyond EOF, return -ENXIO. 2480 * If we can't find out, return a negative errno other than -ENXIO. 2481 */ 2482 static int find_allocation(BlockDriverState *bs, off_t start, 2483 off_t *data, off_t *hole) 2484 { 2485 #if defined SEEK_HOLE && defined SEEK_DATA 2486 BDRVRawState *s = bs->opaque; 2487 off_t offs; 2488 2489 /* 2490 * SEEK_DATA cases: 2491 * D1. offs == start: start is in data 2492 * D2. offs > start: start is in a hole, next data at offs 2493 * D3. offs < 0, errno = ENXIO: either start is in a trailing hole 2494 * or start is beyond EOF 2495 * If the latter happens, the file has been truncated behind 2496 * our back since we opened it. All bets are off then. 2497 * Treating like a trailing hole is simplest. 2498 * D4. offs < 0, errno != ENXIO: we learned nothing 2499 */ 2500 offs = lseek(s->fd, start, SEEK_DATA); 2501 if (offs < 0) { 2502 return -errno; /* D3 or D4 */ 2503 } 2504 2505 if (offs < start) { 2506 /* This is not a valid return by lseek(). We are safe to just return 2507 * -EIO in this case, and we'll treat it like D4. */ 2508 return -EIO; 2509 } 2510 2511 if (offs > start) { 2512 /* D2: in hole, next data at offs */ 2513 *hole = start; 2514 *data = offs; 2515 return 0; 2516 } 2517 2518 /* D1: in data, end not yet known */ 2519 2520 /* 2521 * SEEK_HOLE cases: 2522 * H1. offs == start: start is in a hole 2523 * If this happens here, a hole has been dug behind our back 2524 * since the previous lseek(). 2525 * H2. offs > start: either start is in data, next hole at offs, 2526 * or start is in trailing hole, EOF at offs 2527 * Linux treats trailing holes like any other hole: offs == 2528 * start. Solaris seeks to EOF instead: offs > start (blech). 2529 * If that happens here, a hole has been dug behind our back 2530 * since the previous lseek(). 2531 * H3. offs < 0, errno = ENXIO: start is beyond EOF 2532 * If this happens, the file has been truncated behind our 2533 * back since we opened it. Treat it like a trailing hole. 2534 * H4. offs < 0, errno != ENXIO: we learned nothing 2535 * Pretend we know nothing at all, i.e. "forget" about D1. 2536 */ 2537 offs = lseek(s->fd, start, SEEK_HOLE); 2538 if (offs < 0) { 2539 return -errno; /* D1 and (H3 or H4) */ 2540 } 2541 2542 if (offs < start) { 2543 /* This is not a valid return by lseek(). We are safe to just return 2544 * -EIO in this case, and we'll treat it like H4. */ 2545 return -EIO; 2546 } 2547 2548 if (offs > start) { 2549 /* 2550 * D1 and H2: either in data, next hole at offs, or it was in 2551 * data but is now in a trailing hole. In the latter case, 2552 * all bets are off. Treating it as if it there was data all 2553 * the way to EOF is safe, so simply do that. 2554 */ 2555 *data = start; 2556 *hole = offs; 2557 return 0; 2558 } 2559 2560 /* D1 and H1 */ 2561 return -EBUSY; 2562 #else 2563 return -ENOTSUP; 2564 #endif 2565 } 2566 2567 /* 2568 * Returns the allocation status of the specified offset. 2569 * 2570 * The block layer guarantees 'offset' and 'bytes' are within bounds. 2571 * 2572 * 'pnum' is set to the number of bytes (including and immediately following 2573 * the specified offset) that are known to be in the same 2574 * allocated/unallocated state. 2575 * 2576 * 'bytes' is the max value 'pnum' should be set to. 2577 */ 2578 static int coroutine_fn raw_co_block_status(BlockDriverState *bs, 2579 bool want_zero, 2580 int64_t offset, 2581 int64_t bytes, int64_t *pnum, 2582 int64_t *map, 2583 BlockDriverState **file) 2584 { 2585 off_t data = 0, hole = 0; 2586 int ret; 2587 2588 assert(QEMU_IS_ALIGNED(offset | bytes, bs->bl.request_alignment)); 2589 2590 ret = fd_open(bs); 2591 if (ret < 0) { 2592 return ret; 2593 } 2594 2595 if (!want_zero) { 2596 *pnum = bytes; 2597 *map = offset; 2598 *file = bs; 2599 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 2600 } 2601 2602 ret = find_allocation(bs, offset, &data, &hole); 2603 if (ret == -ENXIO) { 2604 /* Trailing hole */ 2605 *pnum = bytes; 2606 ret = BDRV_BLOCK_ZERO; 2607 } else if (ret < 0) { 2608 /* No info available, so pretend there are no holes */ 2609 *pnum = bytes; 2610 ret = BDRV_BLOCK_DATA; 2611 } else if (data == offset) { 2612 /* On a data extent, compute bytes to the end of the extent, 2613 * possibly including a partial sector at EOF. */ 2614 *pnum = MIN(bytes, hole - offset); 2615 2616 /* 2617 * We are not allowed to return partial sectors, though, so 2618 * round up if necessary. 2619 */ 2620 if (!QEMU_IS_ALIGNED(*pnum, bs->bl.request_alignment)) { 2621 int64_t file_length = raw_getlength(bs); 2622 if (file_length > 0) { 2623 /* Ignore errors, this is just a safeguard */ 2624 assert(hole == file_length); 2625 } 2626 *pnum = ROUND_UP(*pnum, bs->bl.request_alignment); 2627 } 2628 2629 ret = BDRV_BLOCK_DATA; 2630 } else { 2631 /* On a hole, compute bytes to the beginning of the next extent. */ 2632 assert(hole == offset); 2633 *pnum = MIN(bytes, data - offset); 2634 ret = BDRV_BLOCK_ZERO; 2635 } 2636 *map = offset; 2637 *file = bs; 2638 return ret | BDRV_BLOCK_OFFSET_VALID; 2639 } 2640 2641 #if defined(__linux__) 2642 /* Verify that the file is not in the page cache */ 2643 static void check_cache_dropped(BlockDriverState *bs, Error **errp) 2644 { 2645 const size_t window_size = 128 * 1024 * 1024; 2646 BDRVRawState *s = bs->opaque; 2647 void *window = NULL; 2648 size_t length = 0; 2649 unsigned char *vec; 2650 size_t page_size; 2651 off_t offset; 2652 off_t end; 2653 2654 /* mincore(2) page status information requires 1 byte per page */ 2655 page_size = sysconf(_SC_PAGESIZE); 2656 vec = g_malloc(DIV_ROUND_UP(window_size, page_size)); 2657 2658 end = raw_getlength(bs); 2659 2660 for (offset = 0; offset < end; offset += window_size) { 2661 void *new_window; 2662 size_t new_length; 2663 size_t vec_end; 2664 size_t i; 2665 int ret; 2666 2667 /* Unmap previous window if size has changed */ 2668 new_length = MIN(end - offset, window_size); 2669 if (new_length != length) { 2670 munmap(window, length); 2671 window = NULL; 2672 length = 0; 2673 } 2674 2675 new_window = mmap(window, new_length, PROT_NONE, MAP_PRIVATE, 2676 s->fd, offset); 2677 if (new_window == MAP_FAILED) { 2678 error_setg_errno(errp, errno, "mmap failed"); 2679 break; 2680 } 2681 2682 window = new_window; 2683 length = new_length; 2684 2685 ret = mincore(window, length, vec); 2686 if (ret < 0) { 2687 error_setg_errno(errp, errno, "mincore failed"); 2688 break; 2689 } 2690 2691 vec_end = DIV_ROUND_UP(length, page_size); 2692 for (i = 0; i < vec_end; i++) { 2693 if (vec[i] & 0x1) { 2694 break; 2695 } 2696 } 2697 if (i < vec_end) { 2698 error_setg(errp, "page cache still in use!"); 2699 break; 2700 } 2701 } 2702 2703 if (window) { 2704 munmap(window, length); 2705 } 2706 2707 g_free(vec); 2708 } 2709 #endif /* __linux__ */ 2710 2711 static void coroutine_fn raw_co_invalidate_cache(BlockDriverState *bs, 2712 Error **errp) 2713 { 2714 BDRVRawState *s = bs->opaque; 2715 int ret; 2716 2717 ret = fd_open(bs); 2718 if (ret < 0) { 2719 error_setg_errno(errp, -ret, "The file descriptor is not open"); 2720 return; 2721 } 2722 2723 if (!s->drop_cache) { 2724 return; 2725 } 2726 2727 if (s->open_flags & O_DIRECT) { 2728 return; /* No host kernel page cache */ 2729 } 2730 2731 #if defined(__linux__) 2732 /* This sets the scene for the next syscall... */ 2733 ret = bdrv_co_flush(bs); 2734 if (ret < 0) { 2735 error_setg_errno(errp, -ret, "flush failed"); 2736 return; 2737 } 2738 2739 /* Linux does not invalidate pages that are dirty, locked, or mmapped by a 2740 * process. These limitations are okay because we just fsynced the file, 2741 * we don't use mmap, and the file should not be in use by other processes. 2742 */ 2743 ret = posix_fadvise(s->fd, 0, 0, POSIX_FADV_DONTNEED); 2744 if (ret != 0) { /* the return value is a positive errno */ 2745 error_setg_errno(errp, ret, "fadvise failed"); 2746 return; 2747 } 2748 2749 if (s->check_cache_dropped) { 2750 check_cache_dropped(bs, errp); 2751 } 2752 #else /* __linux__ */ 2753 /* Do nothing. Live migration to a remote host with cache.direct=off is 2754 * unsupported on other host operating systems. Cache consistency issues 2755 * may occur but no error is reported here, partly because that's the 2756 * historical behavior and partly because it's hard to differentiate valid 2757 * configurations that should not cause errors. 2758 */ 2759 #endif /* !__linux__ */ 2760 } 2761 2762 static void raw_account_discard(BDRVRawState *s, uint64_t nbytes, int ret) 2763 { 2764 if (ret) { 2765 s->stats.discard_nb_failed++; 2766 } else { 2767 s->stats.discard_nb_ok++; 2768 s->stats.discard_bytes_ok += nbytes; 2769 } 2770 } 2771 2772 static coroutine_fn int 2773 raw_do_pdiscard(BlockDriverState *bs, int64_t offset, int bytes, bool blkdev) 2774 { 2775 BDRVRawState *s = bs->opaque; 2776 RawPosixAIOData acb; 2777 int ret; 2778 2779 acb = (RawPosixAIOData) { 2780 .bs = bs, 2781 .aio_fildes = s->fd, 2782 .aio_type = QEMU_AIO_DISCARD, 2783 .aio_offset = offset, 2784 .aio_nbytes = bytes, 2785 }; 2786 2787 if (blkdev) { 2788 acb.aio_type |= QEMU_AIO_BLKDEV; 2789 } 2790 2791 ret = raw_thread_pool_submit(bs, handle_aiocb_discard, &acb); 2792 raw_account_discard(s, bytes, ret); 2793 return ret; 2794 } 2795 2796 static coroutine_fn int 2797 raw_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes) 2798 { 2799 return raw_do_pdiscard(bs, offset, bytes, false); 2800 } 2801 2802 static int coroutine_fn 2803 raw_do_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int bytes, 2804 BdrvRequestFlags flags, bool blkdev) 2805 { 2806 BDRVRawState *s = bs->opaque; 2807 RawPosixAIOData acb; 2808 ThreadPoolFunc *handler; 2809 2810 #ifdef CONFIG_FALLOCATE 2811 if (offset + bytes > bs->total_sectors * BDRV_SECTOR_SIZE) { 2812 BdrvTrackedRequest *req; 2813 uint64_t end; 2814 2815 /* 2816 * This is a workaround for a bug in the Linux XFS driver, 2817 * where writes submitted through the AIO interface will be 2818 * discarded if they happen beyond a concurrently running 2819 * fallocate() that increases the file length (i.e., both the 2820 * write and the fallocate() happen beyond the EOF). 2821 * 2822 * To work around it, we extend the tracked request for this 2823 * zero write until INT64_MAX (effectively infinity), and mark 2824 * it as serializing. 2825 * 2826 * We have to enable this workaround for all filesystems and 2827 * AIO modes (not just XFS with aio=native), because for 2828 * remote filesystems we do not know the host configuration. 2829 */ 2830 2831 req = bdrv_co_get_self_request(bs); 2832 assert(req); 2833 assert(req->type == BDRV_TRACKED_WRITE); 2834 assert(req->offset <= offset); 2835 assert(req->offset + req->bytes >= offset + bytes); 2836 2837 end = INT64_MAX & -(uint64_t)bs->bl.request_alignment; 2838 req->bytes = end - req->offset; 2839 req->overlap_bytes = req->bytes; 2840 2841 bdrv_mark_request_serialising(req, bs->bl.request_alignment); 2842 } 2843 #endif 2844 2845 acb = (RawPosixAIOData) { 2846 .bs = bs, 2847 .aio_fildes = s->fd, 2848 .aio_type = QEMU_AIO_WRITE_ZEROES, 2849 .aio_offset = offset, 2850 .aio_nbytes = bytes, 2851 }; 2852 2853 if (blkdev) { 2854 acb.aio_type |= QEMU_AIO_BLKDEV; 2855 } 2856 if (flags & BDRV_REQ_NO_FALLBACK) { 2857 acb.aio_type |= QEMU_AIO_NO_FALLBACK; 2858 } 2859 2860 if (flags & BDRV_REQ_MAY_UNMAP) { 2861 acb.aio_type |= QEMU_AIO_DISCARD; 2862 handler = handle_aiocb_write_zeroes_unmap; 2863 } else { 2864 handler = handle_aiocb_write_zeroes; 2865 } 2866 2867 return raw_thread_pool_submit(bs, handler, &acb); 2868 } 2869 2870 static int coroutine_fn raw_co_pwrite_zeroes( 2871 BlockDriverState *bs, int64_t offset, 2872 int bytes, BdrvRequestFlags flags) 2873 { 2874 return raw_do_pwrite_zeroes(bs, offset, bytes, flags, false); 2875 } 2876 2877 static int raw_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 2878 { 2879 return 0; 2880 } 2881 2882 static BlockStatsSpecificFile get_blockstats_specific_file(BlockDriverState *bs) 2883 { 2884 BDRVRawState *s = bs->opaque; 2885 return (BlockStatsSpecificFile) { 2886 .discard_nb_ok = s->stats.discard_nb_ok, 2887 .discard_nb_failed = s->stats.discard_nb_failed, 2888 .discard_bytes_ok = s->stats.discard_bytes_ok, 2889 }; 2890 } 2891 2892 static BlockStatsSpecific *raw_get_specific_stats(BlockDriverState *bs) 2893 { 2894 BlockStatsSpecific *stats = g_new(BlockStatsSpecific, 1); 2895 2896 stats->driver = BLOCKDEV_DRIVER_FILE; 2897 stats->u.file = get_blockstats_specific_file(bs); 2898 2899 return stats; 2900 } 2901 2902 static BlockStatsSpecific *hdev_get_specific_stats(BlockDriverState *bs) 2903 { 2904 BlockStatsSpecific *stats = g_new(BlockStatsSpecific, 1); 2905 2906 stats->driver = BLOCKDEV_DRIVER_HOST_DEVICE; 2907 stats->u.host_device = get_blockstats_specific_file(bs); 2908 2909 return stats; 2910 } 2911 2912 static QemuOptsList raw_create_opts = { 2913 .name = "raw-create-opts", 2914 .head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head), 2915 .desc = { 2916 { 2917 .name = BLOCK_OPT_SIZE, 2918 .type = QEMU_OPT_SIZE, 2919 .help = "Virtual disk size" 2920 }, 2921 { 2922 .name = BLOCK_OPT_NOCOW, 2923 .type = QEMU_OPT_BOOL, 2924 .help = "Turn off copy-on-write (valid only on btrfs)" 2925 }, 2926 { 2927 .name = BLOCK_OPT_PREALLOC, 2928 .type = QEMU_OPT_STRING, 2929 .help = "Preallocation mode (allowed values: off" 2930 #ifdef CONFIG_POSIX_FALLOCATE 2931 ", falloc" 2932 #endif 2933 ", full)" 2934 }, 2935 { /* end of list */ } 2936 } 2937 }; 2938 2939 static int raw_check_perm(BlockDriverState *bs, uint64_t perm, uint64_t shared, 2940 Error **errp) 2941 { 2942 BDRVRawState *s = bs->opaque; 2943 BDRVRawReopenState *rs = NULL; 2944 int open_flags; 2945 int ret; 2946 2947 if (s->perm_change_fd) { 2948 /* 2949 * In the context of reopen, this function may be called several times 2950 * (directly and recursively while change permissions of the parent). 2951 * This is even true for children that don't inherit from the original 2952 * reopen node, so s->reopen_state is not set. 2953 * 2954 * Ignore all but the first call. 2955 */ 2956 return 0; 2957 } 2958 2959 if (s->reopen_state) { 2960 /* We already have a new file descriptor to set permissions for */ 2961 assert(s->reopen_state->perm == perm); 2962 assert(s->reopen_state->shared_perm == shared); 2963 rs = s->reopen_state->opaque; 2964 s->perm_change_fd = rs->fd; 2965 s->perm_change_flags = rs->open_flags; 2966 } else { 2967 /* We may need a new fd if auto-read-only switches the mode */ 2968 ret = raw_reconfigure_getfd(bs, bs->open_flags, &open_flags, perm, 2969 false, errp); 2970 if (ret < 0) { 2971 return ret; 2972 } else if (ret != s->fd) { 2973 s->perm_change_fd = ret; 2974 s->perm_change_flags = open_flags; 2975 } 2976 } 2977 2978 /* Prepare permissions on old fd to avoid conflicts between old and new, 2979 * but keep everything locked that new will need. */ 2980 ret = raw_handle_perm_lock(bs, RAW_PL_PREPARE, perm, shared, errp); 2981 if (ret < 0) { 2982 goto fail; 2983 } 2984 2985 /* Copy locks to the new fd */ 2986 if (s->perm_change_fd) { 2987 ret = raw_apply_lock_bytes(NULL, s->perm_change_fd, perm, ~shared, 2988 false, errp); 2989 if (ret < 0) { 2990 raw_handle_perm_lock(bs, RAW_PL_ABORT, 0, 0, NULL); 2991 goto fail; 2992 } 2993 } 2994 return 0; 2995 2996 fail: 2997 if (s->perm_change_fd && !s->reopen_state) { 2998 qemu_close(s->perm_change_fd); 2999 } 3000 s->perm_change_fd = 0; 3001 return ret; 3002 } 3003 3004 static void raw_set_perm(BlockDriverState *bs, uint64_t perm, uint64_t shared) 3005 { 3006 BDRVRawState *s = bs->opaque; 3007 3008 /* For reopen, we have already switched to the new fd (.bdrv_set_perm is 3009 * called after .bdrv_reopen_commit) */ 3010 if (s->perm_change_fd && s->fd != s->perm_change_fd) { 3011 qemu_close(s->fd); 3012 s->fd = s->perm_change_fd; 3013 s->open_flags = s->perm_change_flags; 3014 } 3015 s->perm_change_fd = 0; 3016 3017 raw_handle_perm_lock(bs, RAW_PL_COMMIT, perm, shared, NULL); 3018 s->perm = perm; 3019 s->shared_perm = shared; 3020 } 3021 3022 static void raw_abort_perm_update(BlockDriverState *bs) 3023 { 3024 BDRVRawState *s = bs->opaque; 3025 3026 /* For reopen, .bdrv_reopen_abort is called afterwards and will close 3027 * the file descriptor. */ 3028 if (s->perm_change_fd && !s->reopen_state) { 3029 qemu_close(s->perm_change_fd); 3030 } 3031 s->perm_change_fd = 0; 3032 3033 raw_handle_perm_lock(bs, RAW_PL_ABORT, 0, 0, NULL); 3034 } 3035 3036 static int coroutine_fn raw_co_copy_range_from( 3037 BlockDriverState *bs, BdrvChild *src, uint64_t src_offset, 3038 BdrvChild *dst, uint64_t dst_offset, uint64_t bytes, 3039 BdrvRequestFlags read_flags, BdrvRequestFlags write_flags) 3040 { 3041 return bdrv_co_copy_range_to(src, src_offset, dst, dst_offset, bytes, 3042 read_flags, write_flags); 3043 } 3044 3045 static int coroutine_fn raw_co_copy_range_to(BlockDriverState *bs, 3046 BdrvChild *src, 3047 uint64_t src_offset, 3048 BdrvChild *dst, 3049 uint64_t dst_offset, 3050 uint64_t bytes, 3051 BdrvRequestFlags read_flags, 3052 BdrvRequestFlags write_flags) 3053 { 3054 RawPosixAIOData acb; 3055 BDRVRawState *s = bs->opaque; 3056 BDRVRawState *src_s; 3057 3058 assert(dst->bs == bs); 3059 if (src->bs->drv->bdrv_co_copy_range_to != raw_co_copy_range_to) { 3060 return -ENOTSUP; 3061 } 3062 3063 src_s = src->bs->opaque; 3064 if (fd_open(src->bs) < 0 || fd_open(dst->bs) < 0) { 3065 return -EIO; 3066 } 3067 3068 acb = (RawPosixAIOData) { 3069 .bs = bs, 3070 .aio_type = QEMU_AIO_COPY_RANGE, 3071 .aio_fildes = src_s->fd, 3072 .aio_offset = src_offset, 3073 .aio_nbytes = bytes, 3074 .copy_range = { 3075 .aio_fd2 = s->fd, 3076 .aio_offset2 = dst_offset, 3077 }, 3078 }; 3079 3080 return raw_thread_pool_submit(bs, handle_aiocb_copy_range, &acb); 3081 } 3082 3083 BlockDriver bdrv_file = { 3084 .format_name = "file", 3085 .protocol_name = "file", 3086 .instance_size = sizeof(BDRVRawState), 3087 .bdrv_needs_filename = true, 3088 .bdrv_probe = NULL, /* no probe for protocols */ 3089 .bdrv_parse_filename = raw_parse_filename, 3090 .bdrv_file_open = raw_open, 3091 .bdrv_reopen_prepare = raw_reopen_prepare, 3092 .bdrv_reopen_commit = raw_reopen_commit, 3093 .bdrv_reopen_abort = raw_reopen_abort, 3094 .bdrv_close = raw_close, 3095 .bdrv_co_create = raw_co_create, 3096 .bdrv_co_create_opts = raw_co_create_opts, 3097 .bdrv_has_zero_init = bdrv_has_zero_init_1, 3098 .bdrv_co_block_status = raw_co_block_status, 3099 .bdrv_co_invalidate_cache = raw_co_invalidate_cache, 3100 .bdrv_co_pwrite_zeroes = raw_co_pwrite_zeroes, 3101 .bdrv_co_delete_file = raw_co_delete_file, 3102 3103 .bdrv_co_preadv = raw_co_preadv, 3104 .bdrv_co_pwritev = raw_co_pwritev, 3105 .bdrv_co_flush_to_disk = raw_co_flush_to_disk, 3106 .bdrv_co_pdiscard = raw_co_pdiscard, 3107 .bdrv_co_copy_range_from = raw_co_copy_range_from, 3108 .bdrv_co_copy_range_to = raw_co_copy_range_to, 3109 .bdrv_refresh_limits = raw_refresh_limits, 3110 .bdrv_io_plug = raw_aio_plug, 3111 .bdrv_io_unplug = raw_aio_unplug, 3112 .bdrv_attach_aio_context = raw_aio_attach_aio_context, 3113 3114 .bdrv_co_truncate = raw_co_truncate, 3115 .bdrv_getlength = raw_getlength, 3116 .bdrv_get_info = raw_get_info, 3117 .bdrv_get_allocated_file_size 3118 = raw_get_allocated_file_size, 3119 .bdrv_get_specific_stats = raw_get_specific_stats, 3120 .bdrv_check_perm = raw_check_perm, 3121 .bdrv_set_perm = raw_set_perm, 3122 .bdrv_abort_perm_update = raw_abort_perm_update, 3123 .create_opts = &raw_create_opts, 3124 .mutable_opts = mutable_opts, 3125 }; 3126 3127 /***********************************************/ 3128 /* host device */ 3129 3130 #if defined(__APPLE__) && defined(__MACH__) 3131 static kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath, 3132 CFIndex maxPathSize, int flags); 3133 static char *FindEjectableOpticalMedia(io_iterator_t *mediaIterator) 3134 { 3135 kern_return_t kernResult = KERN_FAILURE; 3136 mach_port_t masterPort; 3137 CFMutableDictionaryRef classesToMatch; 3138 const char *matching_array[] = {kIODVDMediaClass, kIOCDMediaClass}; 3139 char *mediaType = NULL; 3140 3141 kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort ); 3142 if ( KERN_SUCCESS != kernResult ) { 3143 printf( "IOMasterPort returned %d\n", kernResult ); 3144 } 3145 3146 int index; 3147 for (index = 0; index < ARRAY_SIZE(matching_array); index++) { 3148 classesToMatch = IOServiceMatching(matching_array[index]); 3149 if (classesToMatch == NULL) { 3150 error_report("IOServiceMatching returned NULL for %s", 3151 matching_array[index]); 3152 continue; 3153 } 3154 CFDictionarySetValue(classesToMatch, CFSTR(kIOMediaEjectableKey), 3155 kCFBooleanTrue); 3156 kernResult = IOServiceGetMatchingServices(masterPort, classesToMatch, 3157 mediaIterator); 3158 if (kernResult != KERN_SUCCESS) { 3159 error_report("Note: IOServiceGetMatchingServices returned %d", 3160 kernResult); 3161 continue; 3162 } 3163 3164 /* If a match was found, leave the loop */ 3165 if (*mediaIterator != 0) { 3166 trace_file_FindEjectableOpticalMedia(matching_array[index]); 3167 mediaType = g_strdup(matching_array[index]); 3168 break; 3169 } 3170 } 3171 return mediaType; 3172 } 3173 3174 kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath, 3175 CFIndex maxPathSize, int flags) 3176 { 3177 io_object_t nextMedia; 3178 kern_return_t kernResult = KERN_FAILURE; 3179 *bsdPath = '\0'; 3180 nextMedia = IOIteratorNext( mediaIterator ); 3181 if ( nextMedia ) 3182 { 3183 CFTypeRef bsdPathAsCFString; 3184 bsdPathAsCFString = IORegistryEntryCreateCFProperty( nextMedia, CFSTR( kIOBSDNameKey ), kCFAllocatorDefault, 0 ); 3185 if ( bsdPathAsCFString ) { 3186 size_t devPathLength; 3187 strcpy( bsdPath, _PATH_DEV ); 3188 if (flags & BDRV_O_NOCACHE) { 3189 strcat(bsdPath, "r"); 3190 } 3191 devPathLength = strlen( bsdPath ); 3192 if ( CFStringGetCString( bsdPathAsCFString, bsdPath + devPathLength, maxPathSize - devPathLength, kCFStringEncodingASCII ) ) { 3193 kernResult = KERN_SUCCESS; 3194 } 3195 CFRelease( bsdPathAsCFString ); 3196 } 3197 IOObjectRelease( nextMedia ); 3198 } 3199 3200 return kernResult; 3201 } 3202 3203 /* Sets up a real cdrom for use in QEMU */ 3204 static bool setup_cdrom(char *bsd_path, Error **errp) 3205 { 3206 int index, num_of_test_partitions = 2, fd; 3207 char test_partition[MAXPATHLEN]; 3208 bool partition_found = false; 3209 3210 /* look for a working partition */ 3211 for (index = 0; index < num_of_test_partitions; index++) { 3212 snprintf(test_partition, sizeof(test_partition), "%ss%d", bsd_path, 3213 index); 3214 fd = qemu_open(test_partition, O_RDONLY | O_BINARY | O_LARGEFILE); 3215 if (fd >= 0) { 3216 partition_found = true; 3217 qemu_close(fd); 3218 break; 3219 } 3220 } 3221 3222 /* if a working partition on the device was not found */ 3223 if (partition_found == false) { 3224 error_setg(errp, "Failed to find a working partition on disc"); 3225 } else { 3226 trace_file_setup_cdrom(test_partition); 3227 pstrcpy(bsd_path, MAXPATHLEN, test_partition); 3228 } 3229 return partition_found; 3230 } 3231 3232 /* Prints directions on mounting and unmounting a device */ 3233 static void print_unmounting_directions(const char *file_name) 3234 { 3235 error_report("If device %s is mounted on the desktop, unmount" 3236 " it first before using it in QEMU", file_name); 3237 error_report("Command to unmount device: diskutil unmountDisk %s", 3238 file_name); 3239 error_report("Command to mount device: diskutil mountDisk %s", file_name); 3240 } 3241 3242 #endif /* defined(__APPLE__) && defined(__MACH__) */ 3243 3244 static int hdev_probe_device(const char *filename) 3245 { 3246 struct stat st; 3247 3248 /* allow a dedicated CD-ROM driver to match with a higher priority */ 3249 if (strstart(filename, "/dev/cdrom", NULL)) 3250 return 50; 3251 3252 if (stat(filename, &st) >= 0 && 3253 (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) { 3254 return 100; 3255 } 3256 3257 return 0; 3258 } 3259 3260 static int check_hdev_writable(BDRVRawState *s) 3261 { 3262 #if defined(BLKROGET) 3263 /* Linux block devices can be configured "read-only" using blockdev(8). 3264 * This is independent of device node permissions and therefore open(2) 3265 * with O_RDWR succeeds. Actual writes fail with EPERM. 3266 * 3267 * bdrv_open() is supposed to fail if the disk is read-only. Explicitly 3268 * check for read-only block devices so that Linux block devices behave 3269 * properly. 3270 */ 3271 struct stat st; 3272 int readonly = 0; 3273 3274 if (fstat(s->fd, &st)) { 3275 return -errno; 3276 } 3277 3278 if (!S_ISBLK(st.st_mode)) { 3279 return 0; 3280 } 3281 3282 if (ioctl(s->fd, BLKROGET, &readonly) < 0) { 3283 return -errno; 3284 } 3285 3286 if (readonly) { 3287 return -EACCES; 3288 } 3289 #endif /* defined(BLKROGET) */ 3290 return 0; 3291 } 3292 3293 static void hdev_parse_filename(const char *filename, QDict *options, 3294 Error **errp) 3295 { 3296 bdrv_parse_filename_strip_prefix(filename, "host_device:", options); 3297 } 3298 3299 static bool hdev_is_sg(BlockDriverState *bs) 3300 { 3301 3302 #if defined(__linux__) 3303 3304 BDRVRawState *s = bs->opaque; 3305 struct stat st; 3306 struct sg_scsi_id scsiid; 3307 int sg_version; 3308 int ret; 3309 3310 if (stat(bs->filename, &st) < 0 || !S_ISCHR(st.st_mode)) { 3311 return false; 3312 } 3313 3314 ret = ioctl(s->fd, SG_GET_VERSION_NUM, &sg_version); 3315 if (ret < 0) { 3316 return false; 3317 } 3318 3319 ret = ioctl(s->fd, SG_GET_SCSI_ID, &scsiid); 3320 if (ret >= 0) { 3321 trace_file_hdev_is_sg(scsiid.scsi_type, sg_version); 3322 return true; 3323 } 3324 3325 #endif 3326 3327 return false; 3328 } 3329 3330 static int hdev_open(BlockDriverState *bs, QDict *options, int flags, 3331 Error **errp) 3332 { 3333 BDRVRawState *s = bs->opaque; 3334 int ret; 3335 3336 #if defined(__APPLE__) && defined(__MACH__) 3337 /* 3338 * Caution: while qdict_get_str() is fine, getting non-string types 3339 * would require more care. When @options come from -blockdev or 3340 * blockdev_add, its members are typed according to the QAPI 3341 * schema, but when they come from -drive, they're all QString. 3342 */ 3343 const char *filename = qdict_get_str(options, "filename"); 3344 char bsd_path[MAXPATHLEN] = ""; 3345 bool error_occurred = false; 3346 3347 /* If using a real cdrom */ 3348 if (strcmp(filename, "/dev/cdrom") == 0) { 3349 char *mediaType = NULL; 3350 kern_return_t ret_val; 3351 io_iterator_t mediaIterator = 0; 3352 3353 mediaType = FindEjectableOpticalMedia(&mediaIterator); 3354 if (mediaType == NULL) { 3355 error_setg(errp, "Please make sure your CD/DVD is in the optical" 3356 " drive"); 3357 error_occurred = true; 3358 goto hdev_open_Mac_error; 3359 } 3360 3361 ret_val = GetBSDPath(mediaIterator, bsd_path, sizeof(bsd_path), flags); 3362 if (ret_val != KERN_SUCCESS) { 3363 error_setg(errp, "Could not get BSD path for optical drive"); 3364 error_occurred = true; 3365 goto hdev_open_Mac_error; 3366 } 3367 3368 /* If a real optical drive was not found */ 3369 if (bsd_path[0] == '\0') { 3370 error_setg(errp, "Failed to obtain bsd path for optical drive"); 3371 error_occurred = true; 3372 goto hdev_open_Mac_error; 3373 } 3374 3375 /* If using a cdrom disc and finding a partition on the disc failed */ 3376 if (strncmp(mediaType, kIOCDMediaClass, 9) == 0 && 3377 setup_cdrom(bsd_path, errp) == false) { 3378 print_unmounting_directions(bsd_path); 3379 error_occurred = true; 3380 goto hdev_open_Mac_error; 3381 } 3382 3383 qdict_put_str(options, "filename", bsd_path); 3384 3385 hdev_open_Mac_error: 3386 g_free(mediaType); 3387 if (mediaIterator) { 3388 IOObjectRelease(mediaIterator); 3389 } 3390 if (error_occurred) { 3391 return -ENOENT; 3392 } 3393 } 3394 #endif /* defined(__APPLE__) && defined(__MACH__) */ 3395 3396 s->type = FTYPE_FILE; 3397 3398 ret = raw_open_common(bs, options, flags, 0, true, errp); 3399 if (ret < 0) { 3400 #if defined(__APPLE__) && defined(__MACH__) 3401 if (*bsd_path) { 3402 filename = bsd_path; 3403 } 3404 /* if a physical device experienced an error while being opened */ 3405 if (strncmp(filename, "/dev/", 5) == 0) { 3406 print_unmounting_directions(filename); 3407 } 3408 #endif /* defined(__APPLE__) && defined(__MACH__) */ 3409 return ret; 3410 } 3411 3412 /* Since this does ioctl the device must be already opened */ 3413 bs->sg = hdev_is_sg(bs); 3414 3415 if (flags & BDRV_O_RDWR) { 3416 ret = check_hdev_writable(s); 3417 if (ret < 0) { 3418 raw_close(bs); 3419 error_setg_errno(errp, -ret, "The device is not writable"); 3420 return ret; 3421 } 3422 } 3423 3424 return ret; 3425 } 3426 3427 #if defined(__linux__) 3428 static int coroutine_fn 3429 hdev_co_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) 3430 { 3431 BDRVRawState *s = bs->opaque; 3432 RawPosixAIOData acb; 3433 int ret; 3434 3435 ret = fd_open(bs); 3436 if (ret < 0) { 3437 return ret; 3438 } 3439 3440 if (req == SG_IO && s->pr_mgr) { 3441 struct sg_io_hdr *io_hdr = buf; 3442 if (io_hdr->cmdp[0] == PERSISTENT_RESERVE_OUT || 3443 io_hdr->cmdp[0] == PERSISTENT_RESERVE_IN) { 3444 return pr_manager_execute(s->pr_mgr, bdrv_get_aio_context(bs), 3445 s->fd, io_hdr); 3446 } 3447 } 3448 3449 acb = (RawPosixAIOData) { 3450 .bs = bs, 3451 .aio_type = QEMU_AIO_IOCTL, 3452 .aio_fildes = s->fd, 3453 .aio_offset = 0, 3454 .ioctl = { 3455 .buf = buf, 3456 .cmd = req, 3457 }, 3458 }; 3459 3460 return raw_thread_pool_submit(bs, handle_aiocb_ioctl, &acb); 3461 } 3462 #endif /* linux */ 3463 3464 static int fd_open(BlockDriverState *bs) 3465 { 3466 BDRVRawState *s = bs->opaque; 3467 3468 /* this is just to ensure s->fd is sane (its called by io ops) */ 3469 if (s->fd >= 0) 3470 return 0; 3471 return -EIO; 3472 } 3473 3474 static coroutine_fn int 3475 hdev_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes) 3476 { 3477 BDRVRawState *s = bs->opaque; 3478 int ret; 3479 3480 ret = fd_open(bs); 3481 if (ret < 0) { 3482 raw_account_discard(s, bytes, ret); 3483 return ret; 3484 } 3485 return raw_do_pdiscard(bs, offset, bytes, true); 3486 } 3487 3488 static coroutine_fn int hdev_co_pwrite_zeroes(BlockDriverState *bs, 3489 int64_t offset, int bytes, BdrvRequestFlags flags) 3490 { 3491 int rc; 3492 3493 rc = fd_open(bs); 3494 if (rc < 0) { 3495 return rc; 3496 } 3497 3498 return raw_do_pwrite_zeroes(bs, offset, bytes, flags, true); 3499 } 3500 3501 static BlockDriver bdrv_host_device = { 3502 .format_name = "host_device", 3503 .protocol_name = "host_device", 3504 .instance_size = sizeof(BDRVRawState), 3505 .bdrv_needs_filename = true, 3506 .bdrv_probe_device = hdev_probe_device, 3507 .bdrv_parse_filename = hdev_parse_filename, 3508 .bdrv_file_open = hdev_open, 3509 .bdrv_close = raw_close, 3510 .bdrv_reopen_prepare = raw_reopen_prepare, 3511 .bdrv_reopen_commit = raw_reopen_commit, 3512 .bdrv_reopen_abort = raw_reopen_abort, 3513 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 3514 .create_opts = &bdrv_create_opts_simple, 3515 .mutable_opts = mutable_opts, 3516 .bdrv_co_invalidate_cache = raw_co_invalidate_cache, 3517 .bdrv_co_pwrite_zeroes = hdev_co_pwrite_zeroes, 3518 3519 .bdrv_co_preadv = raw_co_preadv, 3520 .bdrv_co_pwritev = raw_co_pwritev, 3521 .bdrv_co_flush_to_disk = raw_co_flush_to_disk, 3522 .bdrv_co_pdiscard = hdev_co_pdiscard, 3523 .bdrv_co_copy_range_from = raw_co_copy_range_from, 3524 .bdrv_co_copy_range_to = raw_co_copy_range_to, 3525 .bdrv_refresh_limits = raw_refresh_limits, 3526 .bdrv_io_plug = raw_aio_plug, 3527 .bdrv_io_unplug = raw_aio_unplug, 3528 .bdrv_attach_aio_context = raw_aio_attach_aio_context, 3529 3530 .bdrv_co_truncate = raw_co_truncate, 3531 .bdrv_getlength = raw_getlength, 3532 .bdrv_get_info = raw_get_info, 3533 .bdrv_get_allocated_file_size 3534 = raw_get_allocated_file_size, 3535 .bdrv_get_specific_stats = hdev_get_specific_stats, 3536 .bdrv_check_perm = raw_check_perm, 3537 .bdrv_set_perm = raw_set_perm, 3538 .bdrv_abort_perm_update = raw_abort_perm_update, 3539 .bdrv_probe_blocksizes = hdev_probe_blocksizes, 3540 .bdrv_probe_geometry = hdev_probe_geometry, 3541 3542 /* generic scsi device */ 3543 #ifdef __linux__ 3544 .bdrv_co_ioctl = hdev_co_ioctl, 3545 #endif 3546 }; 3547 3548 #if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) 3549 static void cdrom_parse_filename(const char *filename, QDict *options, 3550 Error **errp) 3551 { 3552 bdrv_parse_filename_strip_prefix(filename, "host_cdrom:", options); 3553 } 3554 #endif 3555 3556 #ifdef __linux__ 3557 static int cdrom_open(BlockDriverState *bs, QDict *options, int flags, 3558 Error **errp) 3559 { 3560 BDRVRawState *s = bs->opaque; 3561 3562 s->type = FTYPE_CD; 3563 3564 /* open will not fail even if no CD is inserted, so add O_NONBLOCK */ 3565 return raw_open_common(bs, options, flags, O_NONBLOCK, true, errp); 3566 } 3567 3568 static int cdrom_probe_device(const char *filename) 3569 { 3570 int fd, ret; 3571 int prio = 0; 3572 struct stat st; 3573 3574 fd = qemu_open(filename, O_RDONLY | O_NONBLOCK); 3575 if (fd < 0) { 3576 goto out; 3577 } 3578 ret = fstat(fd, &st); 3579 if (ret == -1 || !S_ISBLK(st.st_mode)) { 3580 goto outc; 3581 } 3582 3583 /* Attempt to detect via a CDROM specific ioctl */ 3584 ret = ioctl(fd, CDROM_DRIVE_STATUS, CDSL_CURRENT); 3585 if (ret >= 0) 3586 prio = 100; 3587 3588 outc: 3589 qemu_close(fd); 3590 out: 3591 return prio; 3592 } 3593 3594 static bool cdrom_is_inserted(BlockDriverState *bs) 3595 { 3596 BDRVRawState *s = bs->opaque; 3597 int ret; 3598 3599 ret = ioctl(s->fd, CDROM_DRIVE_STATUS, CDSL_CURRENT); 3600 return ret == CDS_DISC_OK; 3601 } 3602 3603 static void cdrom_eject(BlockDriverState *bs, bool eject_flag) 3604 { 3605 BDRVRawState *s = bs->opaque; 3606 3607 if (eject_flag) { 3608 if (ioctl(s->fd, CDROMEJECT, NULL) < 0) 3609 perror("CDROMEJECT"); 3610 } else { 3611 if (ioctl(s->fd, CDROMCLOSETRAY, NULL) < 0) 3612 perror("CDROMEJECT"); 3613 } 3614 } 3615 3616 static void cdrom_lock_medium(BlockDriverState *bs, bool locked) 3617 { 3618 BDRVRawState *s = bs->opaque; 3619 3620 if (ioctl(s->fd, CDROM_LOCKDOOR, locked) < 0) { 3621 /* 3622 * Note: an error can happen if the distribution automatically 3623 * mounts the CD-ROM 3624 */ 3625 /* perror("CDROM_LOCKDOOR"); */ 3626 } 3627 } 3628 3629 static BlockDriver bdrv_host_cdrom = { 3630 .format_name = "host_cdrom", 3631 .protocol_name = "host_cdrom", 3632 .instance_size = sizeof(BDRVRawState), 3633 .bdrv_needs_filename = true, 3634 .bdrv_probe_device = cdrom_probe_device, 3635 .bdrv_parse_filename = cdrom_parse_filename, 3636 .bdrv_file_open = cdrom_open, 3637 .bdrv_close = raw_close, 3638 .bdrv_reopen_prepare = raw_reopen_prepare, 3639 .bdrv_reopen_commit = raw_reopen_commit, 3640 .bdrv_reopen_abort = raw_reopen_abort, 3641 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 3642 .create_opts = &bdrv_create_opts_simple, 3643 .mutable_opts = mutable_opts, 3644 .bdrv_co_invalidate_cache = raw_co_invalidate_cache, 3645 3646 .bdrv_co_preadv = raw_co_preadv, 3647 .bdrv_co_pwritev = raw_co_pwritev, 3648 .bdrv_co_flush_to_disk = raw_co_flush_to_disk, 3649 .bdrv_refresh_limits = raw_refresh_limits, 3650 .bdrv_io_plug = raw_aio_plug, 3651 .bdrv_io_unplug = raw_aio_unplug, 3652 .bdrv_attach_aio_context = raw_aio_attach_aio_context, 3653 3654 .bdrv_co_truncate = raw_co_truncate, 3655 .bdrv_getlength = raw_getlength, 3656 .has_variable_length = true, 3657 .bdrv_get_allocated_file_size 3658 = raw_get_allocated_file_size, 3659 3660 /* removable device support */ 3661 .bdrv_is_inserted = cdrom_is_inserted, 3662 .bdrv_eject = cdrom_eject, 3663 .bdrv_lock_medium = cdrom_lock_medium, 3664 3665 /* generic scsi device */ 3666 .bdrv_co_ioctl = hdev_co_ioctl, 3667 }; 3668 #endif /* __linux__ */ 3669 3670 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__) 3671 static int cdrom_open(BlockDriverState *bs, QDict *options, int flags, 3672 Error **errp) 3673 { 3674 BDRVRawState *s = bs->opaque; 3675 int ret; 3676 3677 s->type = FTYPE_CD; 3678 3679 ret = raw_open_common(bs, options, flags, 0, true, errp); 3680 if (ret) { 3681 return ret; 3682 } 3683 3684 /* make sure the door isn't locked at this time */ 3685 ioctl(s->fd, CDIOCALLOW); 3686 return 0; 3687 } 3688 3689 static int cdrom_probe_device(const char *filename) 3690 { 3691 if (strstart(filename, "/dev/cd", NULL) || 3692 strstart(filename, "/dev/acd", NULL)) 3693 return 100; 3694 return 0; 3695 } 3696 3697 static int cdrom_reopen(BlockDriverState *bs) 3698 { 3699 BDRVRawState *s = bs->opaque; 3700 int fd; 3701 3702 /* 3703 * Force reread of possibly changed/newly loaded disc, 3704 * FreeBSD seems to not notice sometimes... 3705 */ 3706 if (s->fd >= 0) 3707 qemu_close(s->fd); 3708 fd = qemu_open(bs->filename, s->open_flags, 0644); 3709 if (fd < 0) { 3710 s->fd = -1; 3711 return -EIO; 3712 } 3713 s->fd = fd; 3714 3715 /* make sure the door isn't locked at this time */ 3716 ioctl(s->fd, CDIOCALLOW); 3717 return 0; 3718 } 3719 3720 static bool cdrom_is_inserted(BlockDriverState *bs) 3721 { 3722 return raw_getlength(bs) > 0; 3723 } 3724 3725 static void cdrom_eject(BlockDriverState *bs, bool eject_flag) 3726 { 3727 BDRVRawState *s = bs->opaque; 3728 3729 if (s->fd < 0) 3730 return; 3731 3732 (void) ioctl(s->fd, CDIOCALLOW); 3733 3734 if (eject_flag) { 3735 if (ioctl(s->fd, CDIOCEJECT) < 0) 3736 perror("CDIOCEJECT"); 3737 } else { 3738 if (ioctl(s->fd, CDIOCCLOSE) < 0) 3739 perror("CDIOCCLOSE"); 3740 } 3741 3742 cdrom_reopen(bs); 3743 } 3744 3745 static void cdrom_lock_medium(BlockDriverState *bs, bool locked) 3746 { 3747 BDRVRawState *s = bs->opaque; 3748 3749 if (s->fd < 0) 3750 return; 3751 if (ioctl(s->fd, (locked ? CDIOCPREVENT : CDIOCALLOW)) < 0) { 3752 /* 3753 * Note: an error can happen if the distribution automatically 3754 * mounts the CD-ROM 3755 */ 3756 /* perror("CDROM_LOCKDOOR"); */ 3757 } 3758 } 3759 3760 static BlockDriver bdrv_host_cdrom = { 3761 .format_name = "host_cdrom", 3762 .protocol_name = "host_cdrom", 3763 .instance_size = sizeof(BDRVRawState), 3764 .bdrv_needs_filename = true, 3765 .bdrv_probe_device = cdrom_probe_device, 3766 .bdrv_parse_filename = cdrom_parse_filename, 3767 .bdrv_file_open = cdrom_open, 3768 .bdrv_close = raw_close, 3769 .bdrv_reopen_prepare = raw_reopen_prepare, 3770 .bdrv_reopen_commit = raw_reopen_commit, 3771 .bdrv_reopen_abort = raw_reopen_abort, 3772 .bdrv_co_create_opts = bdrv_co_create_opts_simple, 3773 .create_opts = &bdrv_create_opts_simple, 3774 .mutable_opts = mutable_opts, 3775 3776 .bdrv_co_preadv = raw_co_preadv, 3777 .bdrv_co_pwritev = raw_co_pwritev, 3778 .bdrv_co_flush_to_disk = raw_co_flush_to_disk, 3779 .bdrv_refresh_limits = raw_refresh_limits, 3780 .bdrv_io_plug = raw_aio_plug, 3781 .bdrv_io_unplug = raw_aio_unplug, 3782 .bdrv_attach_aio_context = raw_aio_attach_aio_context, 3783 3784 .bdrv_co_truncate = raw_co_truncate, 3785 .bdrv_getlength = raw_getlength, 3786 .has_variable_length = true, 3787 .bdrv_get_allocated_file_size 3788 = raw_get_allocated_file_size, 3789 3790 /* removable device support */ 3791 .bdrv_is_inserted = cdrom_is_inserted, 3792 .bdrv_eject = cdrom_eject, 3793 .bdrv_lock_medium = cdrom_lock_medium, 3794 }; 3795 #endif /* __FreeBSD__ */ 3796 3797 static void bdrv_file_init(void) 3798 { 3799 /* 3800 * Register all the drivers. Note that order is important, the driver 3801 * registered last will get probed first. 3802 */ 3803 bdrv_register(&bdrv_file); 3804 bdrv_register(&bdrv_host_device); 3805 #ifdef __linux__ 3806 bdrv_register(&bdrv_host_cdrom); 3807 #endif 3808 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) 3809 bdrv_register(&bdrv_host_cdrom); 3810 #endif 3811 } 3812 3813 block_init(bdrv_file_init); 3814