2 * Block driver for RAW files (posix)
4 * Copyright (c) 2006 Fabrice Bellard
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
24 #include "qemu-common.h"
25 #include "qemu/timer.h"
27 #include "block/block_int.h"
28 #include "qemu/module.h"
30 #include "block/thread-pool.h"
34 #if defined(__APPLE__) && (__MACH__)
36 #include <sys/param.h>
37 #include <IOKit/IOKitLib.h>
38 #include <IOKit/IOBSD.h>
39 #include <IOKit/storage/IOMediaBSDClient.h>
40 #include <IOKit/storage/IOMedia.h>
41 #include <IOKit/storage/IOCDMedia.h>
42 //#include <IOKit/storage/IOCDTypes.h>
43 #include <CoreFoundation/CoreFoundation.h>
47 #define _POSIX_PTHREAD_SEMANTICS 1
51 #include <sys/types.h>
53 #include <sys/ioctl.h>
54 #include <sys/param.h>
55 #include <linux/cdrom.h>
60 #include <linux/fiemap.h>
62 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE
63 #include <linux/falloc.h>
65 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__)
71 #include <sys/ioctl.h>
72 #include <sys/disklabel.h>
77 #include <sys/ioctl.h>
78 #include <sys/disklabel.h>
84 #include <sys/ioctl.h>
85 #include <sys/diskslice.h>
92 //#define DEBUG_FLOPPY
95 #if defined(DEBUG_BLOCK)
96 #define DEBUG_BLOCK_PRINT(formatCstr, ...) do { if (qemu_log_enabled()) \
97 { qemu_log(formatCstr, ## __VA_ARGS__); qemu_log_flush(); } } while (0)
99 #define DEBUG_BLOCK_PRINT(formatCstr, ...)
102 /* OS X does not have O_DSYNC */
105 #define O_DSYNC O_SYNC
106 #elif defined(O_FSYNC)
107 #define O_DSYNC O_FSYNC
111 /* Approximate O_DIRECT with O_DSYNC if O_DIRECT isn't available */
113 #define O_DIRECT O_DSYNC
120 /* if the FD is not accessed during that time (in ns), we try to
121 reopen it to see if the disk has been changed */
122 #define FD_OPEN_TIMEOUT (1000000000)
124 #define MAX_BLOCKSIZE 4096
126 typedef struct BDRVRawState {
130 #if defined(__linux__)
131 /* linux floppy specific */
132 int64_t fd_open_time;
133 int64_t fd_error_time;
135 int fd_media_changed;
137 #ifdef CONFIG_LINUX_AIO
144 bool has_discard : 1;
147 typedef struct BDRVRawReopenState {
150 #ifdef CONFIG_LINUX_AIO
153 } BDRVRawReopenState;
155 static int fd_open(BlockDriverState *bs);
156 static int64_t raw_getlength(BlockDriverState *bs);
158 typedef struct RawPosixAIOData {
159 BlockDriverState *bs;
162 struct iovec *aio_iov;
167 #define aio_ioctl_cmd aio_nbytes /* for QEMU_AIO_IOCTL */
172 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
173 static int cdrom_reopen(BlockDriverState *bs);
176 #if defined(__NetBSD__)
177 static int raw_normalize_devicepath(const char **filename)
179 static char namebuf[PATH_MAX];
180 const char *dp, *fname;
184 dp = strrchr(fname, '/');
185 if (lstat(fname, &sb) < 0) {
186 fprintf(stderr, "%s: stat failed: %s\n",
187 fname, strerror(errno));
191 if (!S_ISBLK(sb.st_mode)) {
196 snprintf(namebuf, PATH_MAX, "r%s", fname);
198 snprintf(namebuf, PATH_MAX, "%.*s/r%s",
199 (int)(dp - fname), fname, dp + 1);
201 fprintf(stderr, "%s is a block device", fname);
203 fprintf(stderr, ", using %s\n", *filename);
208 static int raw_normalize_devicepath(const char **filename)
214 static void raw_parse_flags(int bdrv_flags, int *open_flags)
216 assert(open_flags != NULL);
218 *open_flags |= O_BINARY;
219 *open_flags &= ~O_ACCMODE;
220 if (bdrv_flags & BDRV_O_RDWR) {
221 *open_flags |= O_RDWR;
223 *open_flags |= O_RDONLY;
226 /* Use O_DSYNC for write-through caching, no flags for write-back caching,
227 * and O_DIRECT for no caching. */
228 if ((bdrv_flags & BDRV_O_NOCACHE)) {
229 *open_flags |= O_DIRECT;
233 #ifdef CONFIG_LINUX_AIO
234 static int raw_set_aio(void **aio_ctx, int *use_aio, int bdrv_flags)
237 assert(aio_ctx != NULL);
238 assert(use_aio != NULL);
240 * Currently Linux do AIO only for files opened with O_DIRECT
241 * specified so check NOCACHE flag too
243 if ((bdrv_flags & (BDRV_O_NOCACHE|BDRV_O_NATIVE_AIO)) ==
244 (BDRV_O_NOCACHE|BDRV_O_NATIVE_AIO)) {
246 /* if non-NULL, laio_init() has already been run */
247 if (*aio_ctx == NULL) {
248 *aio_ctx = laio_init();
265 static QemuOptsList raw_runtime_opts = {
267 .head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head),
271 .type = QEMU_OPT_STRING,
272 .help = "File name of the image",
274 { /* end of list */ }
278 static int raw_open_common(BlockDriverState *bs, QDict *options,
279 int bdrv_flags, int open_flags)
281 BDRVRawState *s = bs->opaque;
283 Error *local_err = NULL;
284 const char *filename;
287 opts = qemu_opts_create_nofail(&raw_runtime_opts);
288 qemu_opts_absorb_qdict(opts, options, &local_err);
289 if (error_is_set(&local_err)) {
290 qerror_report_err(local_err);
291 error_free(local_err);
296 filename = qemu_opt_get(opts, "filename");
298 ret = raw_normalize_devicepath(&filename);
303 s->open_flags = open_flags;
304 raw_parse_flags(bdrv_flags, &s->open_flags);
307 fd = qemu_open(filename, s->open_flags, 0644);
317 #ifdef CONFIG_LINUX_AIO
318 if (raw_set_aio(&s->aio_ctx, &s->use_aio, bdrv_flags)) {
327 if (platform_test_xfs_fd(s->fd)) {
338 static int raw_open(BlockDriverState *bs, QDict *options, int flags,
341 BDRVRawState *s = bs->opaque;
343 s->type = FTYPE_FILE;
344 return raw_open_common(bs, options, flags, 0);
347 static int raw_reopen_prepare(BDRVReopenState *state,
348 BlockReopenQueue *queue, Error **errp)
351 BDRVRawReopenState *raw_s;
354 assert(state != NULL);
355 assert(state->bs != NULL);
357 s = state->bs->opaque;
359 state->opaque = g_malloc0(sizeof(BDRVRawReopenState));
360 raw_s = state->opaque;
362 #ifdef CONFIG_LINUX_AIO
363 raw_s->use_aio = s->use_aio;
365 /* we can use s->aio_ctx instead of a copy, because the use_aio flag is
366 * valid in the 'false' condition even if aio_ctx is set, and raw_set_aio()
367 * won't override aio_ctx if aio_ctx is non-NULL */
368 if (raw_set_aio(&s->aio_ctx, &raw_s->use_aio, state->flags)) {
373 if (s->type == FTYPE_FD || s->type == FTYPE_CD) {
374 raw_s->open_flags |= O_NONBLOCK;
377 raw_parse_flags(state->flags, &raw_s->open_flags);
381 int fcntl_flags = O_APPEND | O_NONBLOCK;
383 fcntl_flags |= O_NOATIME;
387 /* Not all operating systems have O_ASYNC, and those that don't
388 * will not let us track the state into raw_s->open_flags (typically
389 * you achieve the same effect with an ioctl, for example I_SETSIG
390 * on Solaris). But we do not use O_ASYNC, so that's fine.
392 assert((s->open_flags & O_ASYNC) == 0);
395 if ((raw_s->open_flags & ~fcntl_flags) == (s->open_flags & ~fcntl_flags)) {
396 /* dup the original fd */
397 /* TODO: use qemu fcntl wrapper */
398 #ifdef F_DUPFD_CLOEXEC
399 raw_s->fd = fcntl(s->fd, F_DUPFD_CLOEXEC, 0);
401 raw_s->fd = dup(s->fd);
402 if (raw_s->fd != -1) {
403 qemu_set_cloexec(raw_s->fd);
406 if (raw_s->fd >= 0) {
407 ret = fcntl_setfl(raw_s->fd, raw_s->open_flags);
409 qemu_close(raw_s->fd);
415 /* If we cannot use fcntl, or fcntl failed, fall back to qemu_open() */
416 if (raw_s->fd == -1) {
417 assert(!(raw_s->open_flags & O_CREAT));
418 raw_s->fd = qemu_open(state->bs->filename, raw_s->open_flags);
419 if (raw_s->fd == -1) {
427 static void raw_reopen_commit(BDRVReopenState *state)
429 BDRVRawReopenState *raw_s = state->opaque;
430 BDRVRawState *s = state->bs->opaque;
432 s->open_flags = raw_s->open_flags;
436 #ifdef CONFIG_LINUX_AIO
437 s->use_aio = raw_s->use_aio;
440 g_free(state->opaque);
441 state->opaque = NULL;
445 static void raw_reopen_abort(BDRVReopenState *state)
447 BDRVRawReopenState *raw_s = state->opaque;
449 /* nothing to do if NULL, we didn't get far enough */
454 if (raw_s->fd >= 0) {
455 qemu_close(raw_s->fd);
458 g_free(state->opaque);
459 state->opaque = NULL;
463 /* XXX: use host sector size if necessary with:
464 #ifdef DIOCGSECTORSIZE
466 unsigned int sectorsize = 512;
467 if (!ioctl(fd, DIOCGSECTORSIZE, §orsize) &&
468 sectorsize > bufsize)
469 bufsize = sectorsize;
473 uint32_t blockSize = 512;
474 if ( !ioctl( fd, DKIOCGETBLOCKSIZE, &blockSize ) && blockSize > bufsize) {
480 static ssize_t handle_aiocb_ioctl(RawPosixAIOData *aiocb)
484 ret = ioctl(aiocb->aio_fildes, aiocb->aio_ioctl_cmd, aiocb->aio_ioctl_buf);
492 static ssize_t handle_aiocb_flush(RawPosixAIOData *aiocb)
496 ret = qemu_fdatasync(aiocb->aio_fildes);
505 static bool preadv_present = true;
508 qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset)
510 return preadv(fd, iov, nr_iov, offset);
514 qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset)
516 return pwritev(fd, iov, nr_iov, offset);
521 static bool preadv_present = false;
524 qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset)
530 qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset)
537 static ssize_t handle_aiocb_rw_vector(RawPosixAIOData *aiocb)
542 if (aiocb->aio_type & QEMU_AIO_WRITE)
543 len = qemu_pwritev(aiocb->aio_fildes,
548 len = qemu_preadv(aiocb->aio_fildes,
552 } while (len == -1 && errno == EINTR);
561 * Read/writes the data to/from a given linear buffer.
563 * Returns the number of bytes handles or -errno in case of an error. Short
564 * reads are only returned if the end of the file is reached.
566 static ssize_t handle_aiocb_rw_linear(RawPosixAIOData *aiocb, char *buf)
571 while (offset < aiocb->aio_nbytes) {
572 if (aiocb->aio_type & QEMU_AIO_WRITE) {
573 len = pwrite(aiocb->aio_fildes,
574 (const char *)buf + offset,
575 aiocb->aio_nbytes - offset,
576 aiocb->aio_offset + offset);
578 len = pread(aiocb->aio_fildes,
580 aiocb->aio_nbytes - offset,
581 aiocb->aio_offset + offset);
583 if (len == -1 && errno == EINTR) {
585 } else if (len == -1) {
588 } else if (len == 0) {
597 static ssize_t handle_aiocb_rw(RawPosixAIOData *aiocb)
602 if (!(aiocb->aio_type & QEMU_AIO_MISALIGNED)) {
604 * If there is just a single buffer, and it is properly aligned
605 * we can just use plain pread/pwrite without any problems.
607 if (aiocb->aio_niov == 1) {
608 return handle_aiocb_rw_linear(aiocb, aiocb->aio_iov->iov_base);
611 * We have more than one iovec, and all are properly aligned.
613 * Try preadv/pwritev first and fall back to linearizing the
614 * buffer if it's not supported.
616 if (preadv_present) {
617 nbytes = handle_aiocb_rw_vector(aiocb);
618 if (nbytes == aiocb->aio_nbytes ||
619 (nbytes < 0 && nbytes != -ENOSYS)) {
622 preadv_present = false;
626 * XXX(hch): short read/write. no easy way to handle the reminder
627 * using these interfaces. For now retry using plain
633 * Ok, we have to do it the hard way, copy all segments into
634 * a single aligned buffer.
636 buf = qemu_blockalign(aiocb->bs, aiocb->aio_nbytes);
637 if (aiocb->aio_type & QEMU_AIO_WRITE) {
641 for (i = 0; i < aiocb->aio_niov; ++i) {
642 memcpy(p, aiocb->aio_iov[i].iov_base, aiocb->aio_iov[i].iov_len);
643 p += aiocb->aio_iov[i].iov_len;
647 nbytes = handle_aiocb_rw_linear(aiocb, buf);
648 if (!(aiocb->aio_type & QEMU_AIO_WRITE)) {
650 size_t count = aiocb->aio_nbytes, copy;
653 for (i = 0; i < aiocb->aio_niov && count; ++i) {
655 if (copy > aiocb->aio_iov[i].iov_len) {
656 copy = aiocb->aio_iov[i].iov_len;
658 memcpy(aiocb->aio_iov[i].iov_base, p, copy);
669 static int xfs_discard(BDRVRawState *s, int64_t offset, uint64_t bytes)
671 struct xfs_flock64 fl;
673 memset(&fl, 0, sizeof(fl));
674 fl.l_whence = SEEK_SET;
678 if (xfsctl(NULL, s->fd, XFS_IOC_UNRESVSP64, &fl) < 0) {
679 DEBUG_BLOCK_PRINT("cannot punch hole (%s)\n", strerror(errno));
687 static ssize_t handle_aiocb_discard(RawPosixAIOData *aiocb)
689 int ret = -EOPNOTSUPP;
690 BDRVRawState *s = aiocb->bs->opaque;
692 if (s->has_discard == 0) {
696 if (aiocb->aio_type & QEMU_AIO_BLKDEV) {
699 uint64_t range[2] = { aiocb->aio_offset, aiocb->aio_nbytes };
700 if (ioctl(aiocb->aio_fildes, BLKDISCARD, range) == 0) {
703 } while (errno == EINTR);
710 return xfs_discard(s, aiocb->aio_offset, aiocb->aio_nbytes);
714 #ifdef CONFIG_FALLOCATE_PUNCH_HOLE
716 if (fallocate(s->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
717 aiocb->aio_offset, aiocb->aio_nbytes) == 0) {
720 } while (errno == EINTR);
726 if (ret == -ENODEV || ret == -ENOSYS || ret == -EOPNOTSUPP ||
734 static int aio_worker(void *arg)
736 RawPosixAIOData *aiocb = arg;
739 switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
741 ret = handle_aiocb_rw(aiocb);
742 if (ret >= 0 && ret < aiocb->aio_nbytes && aiocb->bs->growable) {
743 iov_memset(aiocb->aio_iov, aiocb->aio_niov, ret,
744 0, aiocb->aio_nbytes - ret);
746 ret = aiocb->aio_nbytes;
748 if (ret == aiocb->aio_nbytes) {
750 } else if (ret >= 0 && ret < aiocb->aio_nbytes) {
755 ret = handle_aiocb_rw(aiocb);
756 if (ret == aiocb->aio_nbytes) {
758 } else if (ret >= 0 && ret < aiocb->aio_nbytes) {
763 ret = handle_aiocb_flush(aiocb);
766 ret = handle_aiocb_ioctl(aiocb);
768 case QEMU_AIO_DISCARD:
769 ret = handle_aiocb_discard(aiocb);
772 fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
777 g_slice_free(RawPosixAIOData, aiocb);
781 static BlockDriverAIOCB *paio_submit(BlockDriverState *bs, int fd,
782 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
783 BlockDriverCompletionFunc *cb, void *opaque, int type)
785 RawPosixAIOData *acb = g_slice_new(RawPosixAIOData);
789 acb->aio_type = type;
790 acb->aio_fildes = fd;
793 acb->aio_iov = qiov->iov;
794 acb->aio_niov = qiov->niov;
796 acb->aio_nbytes = nb_sectors * 512;
797 acb->aio_offset = sector_num * 512;
799 trace_paio_submit(acb, opaque, sector_num, nb_sectors, type);
800 pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
801 return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
804 static BlockDriverAIOCB *raw_aio_submit(BlockDriverState *bs,
805 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
806 BlockDriverCompletionFunc *cb, void *opaque, int type)
808 BDRVRawState *s = bs->opaque;
814 * If O_DIRECT is used the buffer needs to be aligned on a sector
815 * boundary. Check if this is the case or tell the low-level
816 * driver that it needs to copy the buffer.
818 if ((bs->open_flags & BDRV_O_NOCACHE)) {
819 if (!bdrv_qiov_is_aligned(bs, qiov)) {
820 type |= QEMU_AIO_MISALIGNED;
821 #ifdef CONFIG_LINUX_AIO
822 } else if (s->use_aio) {
823 return laio_submit(bs, s->aio_ctx, s->fd, sector_num, qiov,
824 nb_sectors, cb, opaque, type);
829 return paio_submit(bs, s->fd, sector_num, qiov, nb_sectors,
833 static BlockDriverAIOCB *raw_aio_readv(BlockDriverState *bs,
834 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
835 BlockDriverCompletionFunc *cb, void *opaque)
837 return raw_aio_submit(bs, sector_num, qiov, nb_sectors,
838 cb, opaque, QEMU_AIO_READ);
841 static BlockDriverAIOCB *raw_aio_writev(BlockDriverState *bs,
842 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
843 BlockDriverCompletionFunc *cb, void *opaque)
845 return raw_aio_submit(bs, sector_num, qiov, nb_sectors,
846 cb, opaque, QEMU_AIO_WRITE);
849 static BlockDriverAIOCB *raw_aio_flush(BlockDriverState *bs,
850 BlockDriverCompletionFunc *cb, void *opaque)
852 BDRVRawState *s = bs->opaque;
857 return paio_submit(bs, s->fd, 0, NULL, 0, cb, opaque, QEMU_AIO_FLUSH);
860 static void raw_close(BlockDriverState *bs)
862 BDRVRawState *s = bs->opaque;
869 static int raw_truncate(BlockDriverState *bs, int64_t offset)
871 BDRVRawState *s = bs->opaque;
874 if (fstat(s->fd, &st)) {
878 if (S_ISREG(st.st_mode)) {
879 if (ftruncate(s->fd, offset) < 0) {
882 } else if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) {
883 if (offset > raw_getlength(bs)) {
894 static int64_t raw_getlength(BlockDriverState *bs)
896 BDRVRawState *s = bs->opaque;
902 if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) {
905 if (ioctl(fd, DIOCGDINFO, &dl))
907 return (uint64_t)dl.d_secsize *
908 dl.d_partitions[DISKPART(st.st_rdev)].p_size;
912 #elif defined(__NetBSD__)
913 static int64_t raw_getlength(BlockDriverState *bs)
915 BDRVRawState *s = bs->opaque;
921 if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) {
922 struct dkwedge_info dkw;
924 if (ioctl(fd, DIOCGWEDGEINFO, &dkw) != -1) {
925 return dkw.dkw_size * 512;
929 if (ioctl(fd, DIOCGDINFO, &dl))
931 return (uint64_t)dl.d_secsize *
932 dl.d_partitions[DISKPART(st.st_rdev)].p_size;
937 #elif defined(__sun__)
938 static int64_t raw_getlength(BlockDriverState *bs)
940 BDRVRawState *s = bs->opaque;
941 struct dk_minfo minfo;
950 * Use the DKIOCGMEDIAINFO ioctl to read the size.
952 ret = ioctl(s->fd, DKIOCGMEDIAINFO, &minfo);
954 return minfo.dki_lbsize * minfo.dki_capacity;
958 * There are reports that lseek on some devices fails, but
959 * irc discussion said that contingency on contingency was overkill.
961 return lseek(s->fd, 0, SEEK_END);
963 #elif defined(CONFIG_BSD)
964 static int64_t raw_getlength(BlockDriverState *bs)
966 BDRVRawState *s = bs->opaque;
970 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__)
979 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__)
982 if (!fstat(fd, &sb) && (S_IFCHR & sb.st_mode)) {
983 #ifdef DIOCGMEDIASIZE
984 if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size))
985 #elif defined(DIOCGPART)
988 if (ioctl(fd, DIOCGPART, &pi) == 0)
989 size = pi.media_size;
995 #if defined(__APPLE__) && defined(__MACH__)
996 size = LONG_LONG_MAX;
998 size = lseek(fd, 0LL, SEEK_END);
1000 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1003 /* XXX FreeBSD acd returns UINT_MAX sectors for an empty drive */
1004 if (size == 2048LL * (unsigned)-1)
1006 /* XXX no disc? maybe we need to reopen... */
1007 if (size <= 0 && !reopened && cdrom_reopen(bs) >= 0) {
1014 size = lseek(fd, 0, SEEK_END);
1019 static int64_t raw_getlength(BlockDriverState *bs)
1021 BDRVRawState *s = bs->opaque;
1029 return lseek(s->fd, 0, SEEK_END);
1033 static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
1036 BDRVRawState *s = bs->opaque;
1038 if (fstat(s->fd, &st) < 0) {
1041 return (int64_t)st.st_blocks * 512;
1044 static int raw_create(const char *filename, QEMUOptionParameter *options,
1049 int64_t total_size = 0;
1051 /* Read out options */
1052 while (options && options->name) {
1053 if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
1054 total_size = options->value.n / BDRV_SECTOR_SIZE;
1059 fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
1064 if (ftruncate(fd, total_size * BDRV_SECTOR_SIZE) != 0) {
1067 if (qemu_close(fd) != 0) {
1075 * Returns true iff the specified sector is present in the disk image. Drivers
1076 * not implementing the functionality are assumed to not support backing files,
1077 * hence all their sectors are reported as allocated.
1079 * If 'sector_num' is beyond the end of the disk image the return value is 0
1080 * and 'pnum' is set to 0.
1082 * 'pnum' is set to the number of sectors (including and immediately following
1083 * the specified sector) that are known to be in the same
1084 * allocated/unallocated state.
1086 * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
1087 * beyond the end of the disk image it will be clamped.
1089 static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs,
1091 int nb_sectors, int *pnum)
1093 off_t start, data, hole;
1101 start = sector_num * BDRV_SECTOR_SIZE;
1102 ret = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | start;
1104 #ifdef CONFIG_FIEMAP
1106 BDRVRawState *s = bs->opaque;
1109 struct fiemap_extent fe;
1112 f.fm.fm_start = start;
1113 f.fm.fm_length = (int64_t)nb_sectors * BDRV_SECTOR_SIZE;
1115 f.fm.fm_extent_count = 1;
1116 f.fm.fm_reserved = 0;
1117 if (ioctl(s->fd, FS_IOC_FIEMAP, &f) == -1) {
1118 /* Assume everything is allocated. */
1123 if (f.fm.fm_mapped_extents == 0) {
1124 /* No extents found, data is beyond f.fm.fm_start + f.fm.fm_length.
1125 * f.fm.fm_start + f.fm.fm_length must be clamped to the file size!
1127 off_t length = lseek(s->fd, 0, SEEK_END);
1128 hole = f.fm.fm_start;
1129 data = MIN(f.fm.fm_start + f.fm.fm_length, length);
1131 data = f.fe.fe_logical;
1132 hole = f.fe.fe_logical + f.fe.fe_length;
1133 if (f.fe.fe_flags & FIEMAP_EXTENT_UNWRITTEN) {
1134 ret |= BDRV_BLOCK_ZERO;
1138 #elif defined SEEK_HOLE && defined SEEK_DATA
1140 BDRVRawState *s = bs->opaque;
1142 hole = lseek(s->fd, start, SEEK_HOLE);
1144 /* -ENXIO indicates that sector_num was past the end of the file.
1145 * There is a virtual hole there. */
1146 assert(errno != -ENXIO);
1148 /* Most likely EINVAL. Assume everything is allocated. */
1156 /* On a hole. We need another syscall to find its end. */
1157 data = lseek(s->fd, start, SEEK_DATA);
1159 data = lseek(s->fd, 0, SEEK_END);
1164 hole = start + nb_sectors * BDRV_SECTOR_SIZE;
1167 if (data <= start) {
1168 /* On a data extent, compute sectors to the end of the extent. */
1169 *pnum = MIN(nb_sectors, (hole - start) / BDRV_SECTOR_SIZE);
1171 /* On a hole, compute sectors to the beginning of the next extent. */
1172 *pnum = MIN(nb_sectors, (data - start) / BDRV_SECTOR_SIZE);
1173 ret &= ~BDRV_BLOCK_DATA;
1174 ret |= BDRV_BLOCK_ZERO;
1180 static coroutine_fn BlockDriverAIOCB *raw_aio_discard(BlockDriverState *bs,
1181 int64_t sector_num, int nb_sectors,
1182 BlockDriverCompletionFunc *cb, void *opaque)
1184 BDRVRawState *s = bs->opaque;
1186 return paio_submit(bs, s->fd, sector_num, NULL, nb_sectors,
1187 cb, opaque, QEMU_AIO_DISCARD);
1190 static QEMUOptionParameter raw_create_options[] = {
1192 .name = BLOCK_OPT_SIZE,
1194 .help = "Virtual disk size"
1199 static BlockDriver bdrv_file = {
1200 .format_name = "file",
1201 .protocol_name = "file",
1202 .instance_size = sizeof(BDRVRawState),
1203 .bdrv_probe = NULL, /* no probe for protocols */
1204 .bdrv_file_open = raw_open,
1205 .bdrv_reopen_prepare = raw_reopen_prepare,
1206 .bdrv_reopen_commit = raw_reopen_commit,
1207 .bdrv_reopen_abort = raw_reopen_abort,
1208 .bdrv_close = raw_close,
1209 .bdrv_create = raw_create,
1210 .bdrv_has_zero_init = bdrv_has_zero_init_1,
1211 .bdrv_co_get_block_status = raw_co_get_block_status,
1213 .bdrv_aio_readv = raw_aio_readv,
1214 .bdrv_aio_writev = raw_aio_writev,
1215 .bdrv_aio_flush = raw_aio_flush,
1216 .bdrv_aio_discard = raw_aio_discard,
1218 .bdrv_truncate = raw_truncate,
1219 .bdrv_getlength = raw_getlength,
1220 .bdrv_get_allocated_file_size
1221 = raw_get_allocated_file_size,
1223 .create_options = raw_create_options,
1226 /***********************************************/
1229 #if defined(__APPLE__) && defined(__MACH__)
1230 static kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator );
1231 static kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize );
1233 kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator )
1235 kern_return_t kernResult;
1236 mach_port_t masterPort;
1237 CFMutableDictionaryRef classesToMatch;
1239 kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort );
1240 if ( KERN_SUCCESS != kernResult ) {
1241 printf( "IOMasterPort returned %d\n", kernResult );
1244 classesToMatch = IOServiceMatching( kIOCDMediaClass );
1245 if ( classesToMatch == NULL ) {
1246 printf( "IOServiceMatching returned a NULL dictionary.\n" );
1248 CFDictionarySetValue( classesToMatch, CFSTR( kIOMediaEjectableKey ), kCFBooleanTrue );
1250 kernResult = IOServiceGetMatchingServices( masterPort, classesToMatch, mediaIterator );
1251 if ( KERN_SUCCESS != kernResult )
1253 printf( "IOServiceGetMatchingServices returned %d\n", kernResult );
1259 kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize )
1261 io_object_t nextMedia;
1262 kern_return_t kernResult = KERN_FAILURE;
1264 nextMedia = IOIteratorNext( mediaIterator );
1267 CFTypeRef bsdPathAsCFString;
1268 bsdPathAsCFString = IORegistryEntryCreateCFProperty( nextMedia, CFSTR( kIOBSDNameKey ), kCFAllocatorDefault, 0 );
1269 if ( bsdPathAsCFString ) {
1270 size_t devPathLength;
1271 strcpy( bsdPath, _PATH_DEV );
1272 strcat( bsdPath, "r" );
1273 devPathLength = strlen( bsdPath );
1274 if ( CFStringGetCString( bsdPathAsCFString, bsdPath + devPathLength, maxPathSize - devPathLength, kCFStringEncodingASCII ) ) {
1275 kernResult = KERN_SUCCESS;
1277 CFRelease( bsdPathAsCFString );
1279 IOObjectRelease( nextMedia );
1287 static int hdev_probe_device(const char *filename)
1291 /* allow a dedicated CD-ROM driver to match with a higher priority */
1292 if (strstart(filename, "/dev/cdrom", NULL))
1295 if (stat(filename, &st) >= 0 &&
1296 (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
1303 static int check_hdev_writable(BDRVRawState *s)
1305 #if defined(BLKROGET)
1306 /* Linux block devices can be configured "read-only" using blockdev(8).
1307 * This is independent of device node permissions and therefore open(2)
1308 * with O_RDWR succeeds. Actual writes fail with EPERM.
1310 * bdrv_open() is supposed to fail if the disk is read-only. Explicitly
1311 * check for read-only block devices so that Linux block devices behave
1317 if (fstat(s->fd, &st)) {
1321 if (!S_ISBLK(st.st_mode)) {
1325 if (ioctl(s->fd, BLKROGET, &readonly) < 0) {
1332 #endif /* defined(BLKROGET) */
1336 static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
1339 BDRVRawState *s = bs->opaque;
1341 const char *filename = qdict_get_str(options, "filename");
1343 #if defined(__APPLE__) && defined(__MACH__)
1344 if (strstart(filename, "/dev/cdrom", NULL)) {
1345 kern_return_t kernResult;
1346 io_iterator_t mediaIterator;
1347 char bsdPath[ MAXPATHLEN ];
1350 kernResult = FindEjectableCDMedia( &mediaIterator );
1351 kernResult = GetBSDPath( mediaIterator, bsdPath, sizeof( bsdPath ) );
1353 if ( bsdPath[ 0 ] != '\0' ) {
1354 strcat(bsdPath,"s0");
1355 /* some CDs don't have a partition 0 */
1356 fd = qemu_open(bsdPath, O_RDONLY | O_BINARY | O_LARGEFILE);
1358 bsdPath[strlen(bsdPath)-1] = '1';
1363 qdict_put(options, "filename", qstring_from_str(filename));
1366 if ( mediaIterator )
1367 IOObjectRelease( mediaIterator );
1371 s->type = FTYPE_FILE;
1372 #if defined(__linux__)
1374 char resolved_path[ MAXPATHLEN ], *temp;
1376 temp = realpath(filename, resolved_path);
1377 if (temp && strstart(temp, "/dev/sg", NULL)) {
1383 ret = raw_open_common(bs, options, flags, 0);
1388 if (flags & BDRV_O_RDWR) {
1389 ret = check_hdev_writable(s);
1399 #if defined(__linux__)
1400 /* Note: we do not have a reliable method to detect if the floppy is
1401 present. The current method is to try to open the floppy at every
1402 I/O and to keep it opened during a few hundreds of ms. */
1403 static int fd_open(BlockDriverState *bs)
1405 BDRVRawState *s = bs->opaque;
1406 int last_media_present;
1408 if (s->type != FTYPE_FD)
1410 last_media_present = (s->fd >= 0);
1412 (get_clock() - s->fd_open_time) >= FD_OPEN_TIMEOUT) {
1416 printf("Floppy closed\n");
1420 if (s->fd_got_error &&
1421 (get_clock() - s->fd_error_time) < FD_OPEN_TIMEOUT) {
1423 printf("No floppy (open delayed)\n");
1427 s->fd = qemu_open(bs->filename, s->open_flags & ~O_NONBLOCK);
1429 s->fd_error_time = get_clock();
1430 s->fd_got_error = 1;
1431 if (last_media_present)
1432 s->fd_media_changed = 1;
1434 printf("No floppy\n");
1439 printf("Floppy opened\n");
1442 if (!last_media_present)
1443 s->fd_media_changed = 1;
1444 s->fd_open_time = get_clock();
1445 s->fd_got_error = 0;
1449 static int hdev_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
1451 BDRVRawState *s = bs->opaque;
1453 return ioctl(s->fd, req, buf);
1456 static BlockDriverAIOCB *hdev_aio_ioctl(BlockDriverState *bs,
1457 unsigned long int req, void *buf,
1458 BlockDriverCompletionFunc *cb, void *opaque)
1460 BDRVRawState *s = bs->opaque;
1461 RawPosixAIOData *acb;
1464 if (fd_open(bs) < 0)
1467 acb = g_slice_new(RawPosixAIOData);
1469 acb->aio_type = QEMU_AIO_IOCTL;
1470 acb->aio_fildes = s->fd;
1471 acb->aio_offset = 0;
1472 acb->aio_ioctl_buf = buf;
1473 acb->aio_ioctl_cmd = req;
1474 pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
1475 return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
1478 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1479 static int fd_open(BlockDriverState *bs)
1481 BDRVRawState *s = bs->opaque;
1483 /* this is just to ensure s->fd is sane (its called by io ops) */
1488 #else /* !linux && !FreeBSD */
1490 static int fd_open(BlockDriverState *bs)
1495 #endif /* !linux && !FreeBSD */
1497 static coroutine_fn BlockDriverAIOCB *hdev_aio_discard(BlockDriverState *bs,
1498 int64_t sector_num, int nb_sectors,
1499 BlockDriverCompletionFunc *cb, void *opaque)
1501 BDRVRawState *s = bs->opaque;
1503 if (fd_open(bs) < 0) {
1506 return paio_submit(bs, s->fd, sector_num, NULL, nb_sectors,
1507 cb, opaque, QEMU_AIO_DISCARD|QEMU_AIO_BLKDEV);
1510 static int hdev_create(const char *filename, QEMUOptionParameter *options,
1515 struct stat stat_buf;
1516 int64_t total_size = 0;
1518 /* Read out options */
1519 while (options && options->name) {
1520 if (!strcmp(options->name, "size")) {
1521 total_size = options->value.n / BDRV_SECTOR_SIZE;
1526 fd = qemu_open(filename, O_WRONLY | O_BINARY);
1530 if (fstat(fd, &stat_buf) < 0)
1532 else if (!S_ISBLK(stat_buf.st_mode) && !S_ISCHR(stat_buf.st_mode))
1534 else if (lseek(fd, 0, SEEK_END) < total_size * BDRV_SECTOR_SIZE)
1541 static BlockDriver bdrv_host_device = {
1542 .format_name = "host_device",
1543 .protocol_name = "host_device",
1544 .instance_size = sizeof(BDRVRawState),
1545 .bdrv_probe_device = hdev_probe_device,
1546 .bdrv_file_open = hdev_open,
1547 .bdrv_close = raw_close,
1548 .bdrv_reopen_prepare = raw_reopen_prepare,
1549 .bdrv_reopen_commit = raw_reopen_commit,
1550 .bdrv_reopen_abort = raw_reopen_abort,
1551 .bdrv_create = hdev_create,
1552 .create_options = raw_create_options,
1554 .bdrv_aio_readv = raw_aio_readv,
1555 .bdrv_aio_writev = raw_aio_writev,
1556 .bdrv_aio_flush = raw_aio_flush,
1557 .bdrv_aio_discard = hdev_aio_discard,
1559 .bdrv_truncate = raw_truncate,
1560 .bdrv_getlength = raw_getlength,
1561 .bdrv_get_allocated_file_size
1562 = raw_get_allocated_file_size,
1564 /* generic scsi device */
1566 .bdrv_ioctl = hdev_ioctl,
1567 .bdrv_aio_ioctl = hdev_aio_ioctl,
1572 static int floppy_open(BlockDriverState *bs, QDict *options, int flags,
1575 BDRVRawState *s = bs->opaque;
1580 /* open will not fail even if no floppy is inserted, so add O_NONBLOCK */
1581 ret = raw_open_common(bs, options, flags, O_NONBLOCK);
1585 /* close fd so that we can reopen it as needed */
1588 s->fd_media_changed = 1;
1593 static int floppy_probe_device(const char *filename)
1597 struct floppy_struct fdparam;
1600 if (strstart(filename, "/dev/fd", NULL) &&
1601 !strstart(filename, "/dev/fdset/", NULL)) {
1605 fd = qemu_open(filename, O_RDONLY | O_NONBLOCK);
1609 ret = fstat(fd, &st);
1610 if (ret == -1 || !S_ISBLK(st.st_mode)) {
1614 /* Attempt to detect via a floppy specific ioctl */
1615 ret = ioctl(fd, FDGETPRM, &fdparam);
1626 static int floppy_is_inserted(BlockDriverState *bs)
1628 return fd_open(bs) >= 0;
1631 static int floppy_media_changed(BlockDriverState *bs)
1633 BDRVRawState *s = bs->opaque;
1637 * XXX: we do not have a true media changed indication.
1638 * It does not work if the floppy is changed without trying to read it.
1641 ret = s->fd_media_changed;
1642 s->fd_media_changed = 0;
1644 printf("Floppy changed=%d\n", ret);
1649 static void floppy_eject(BlockDriverState *bs, bool eject_flag)
1651 BDRVRawState *s = bs->opaque;
1658 fd = qemu_open(bs->filename, s->open_flags | O_NONBLOCK);
1660 if (ioctl(fd, FDEJECT, 0) < 0)
1666 static BlockDriver bdrv_host_floppy = {
1667 .format_name = "host_floppy",
1668 .protocol_name = "host_floppy",
1669 .instance_size = sizeof(BDRVRawState),
1670 .bdrv_probe_device = floppy_probe_device,
1671 .bdrv_file_open = floppy_open,
1672 .bdrv_close = raw_close,
1673 .bdrv_reopen_prepare = raw_reopen_prepare,
1674 .bdrv_reopen_commit = raw_reopen_commit,
1675 .bdrv_reopen_abort = raw_reopen_abort,
1676 .bdrv_create = hdev_create,
1677 .create_options = raw_create_options,
1679 .bdrv_aio_readv = raw_aio_readv,
1680 .bdrv_aio_writev = raw_aio_writev,
1681 .bdrv_aio_flush = raw_aio_flush,
1683 .bdrv_truncate = raw_truncate,
1684 .bdrv_getlength = raw_getlength,
1685 .bdrv_get_allocated_file_size
1686 = raw_get_allocated_file_size,
1688 /* removable device support */
1689 .bdrv_is_inserted = floppy_is_inserted,
1690 .bdrv_media_changed = floppy_media_changed,
1691 .bdrv_eject = floppy_eject,
1694 static int cdrom_open(BlockDriverState *bs, QDict *options, int flags,
1697 BDRVRawState *s = bs->opaque;
1701 /* open will not fail even if no CD is inserted, so add O_NONBLOCK */
1702 return raw_open_common(bs, options, flags, O_NONBLOCK);
1705 static int cdrom_probe_device(const char *filename)
1711 fd = qemu_open(filename, O_RDONLY | O_NONBLOCK);
1715 ret = fstat(fd, &st);
1716 if (ret == -1 || !S_ISBLK(st.st_mode)) {
1720 /* Attempt to detect via a CDROM specific ioctl */
1721 ret = ioctl(fd, CDROM_DRIVE_STATUS, CDSL_CURRENT);
1731 static int cdrom_is_inserted(BlockDriverState *bs)
1733 BDRVRawState *s = bs->opaque;
1736 ret = ioctl(s->fd, CDROM_DRIVE_STATUS, CDSL_CURRENT);
1737 if (ret == CDS_DISC_OK)
1742 static void cdrom_eject(BlockDriverState *bs, bool eject_flag)
1744 BDRVRawState *s = bs->opaque;
1747 if (ioctl(s->fd, CDROMEJECT, NULL) < 0)
1748 perror("CDROMEJECT");
1750 if (ioctl(s->fd, CDROMCLOSETRAY, NULL) < 0)
1751 perror("CDROMEJECT");
1755 static void cdrom_lock_medium(BlockDriverState *bs, bool locked)
1757 BDRVRawState *s = bs->opaque;
1759 if (ioctl(s->fd, CDROM_LOCKDOOR, locked) < 0) {
1761 * Note: an error can happen if the distribution automatically
1764 /* perror("CDROM_LOCKDOOR"); */
1768 static BlockDriver bdrv_host_cdrom = {
1769 .format_name = "host_cdrom",
1770 .protocol_name = "host_cdrom",
1771 .instance_size = sizeof(BDRVRawState),
1772 .bdrv_probe_device = cdrom_probe_device,
1773 .bdrv_file_open = cdrom_open,
1774 .bdrv_close = raw_close,
1775 .bdrv_reopen_prepare = raw_reopen_prepare,
1776 .bdrv_reopen_commit = raw_reopen_commit,
1777 .bdrv_reopen_abort = raw_reopen_abort,
1778 .bdrv_create = hdev_create,
1779 .create_options = raw_create_options,
1781 .bdrv_aio_readv = raw_aio_readv,
1782 .bdrv_aio_writev = raw_aio_writev,
1783 .bdrv_aio_flush = raw_aio_flush,
1785 .bdrv_truncate = raw_truncate,
1786 .bdrv_getlength = raw_getlength,
1787 .bdrv_get_allocated_file_size
1788 = raw_get_allocated_file_size,
1790 /* removable device support */
1791 .bdrv_is_inserted = cdrom_is_inserted,
1792 .bdrv_eject = cdrom_eject,
1793 .bdrv_lock_medium = cdrom_lock_medium,
1795 /* generic scsi device */
1796 .bdrv_ioctl = hdev_ioctl,
1797 .bdrv_aio_ioctl = hdev_aio_ioctl,
1799 #endif /* __linux__ */
1801 #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__)
1802 static int cdrom_open(BlockDriverState *bs, QDict *options, int flags)
1804 BDRVRawState *s = bs->opaque;
1809 ret = raw_open_common(bs, options, flags, 0);
1813 /* make sure the door isn't locked at this time */
1814 ioctl(s->fd, CDIOCALLOW);
1818 static int cdrom_probe_device(const char *filename)
1820 if (strstart(filename, "/dev/cd", NULL) ||
1821 strstart(filename, "/dev/acd", NULL))
1826 static int cdrom_reopen(BlockDriverState *bs)
1828 BDRVRawState *s = bs->opaque;
1832 * Force reread of possibly changed/newly loaded disc,
1833 * FreeBSD seems to not notice sometimes...
1837 fd = qemu_open(bs->filename, s->open_flags, 0644);
1844 /* make sure the door isn't locked at this time */
1845 ioctl(s->fd, CDIOCALLOW);
1849 static int cdrom_is_inserted(BlockDriverState *bs)
1851 return raw_getlength(bs) > 0;
1854 static void cdrom_eject(BlockDriverState *bs, bool eject_flag)
1856 BDRVRawState *s = bs->opaque;
1861 (void) ioctl(s->fd, CDIOCALLOW);
1864 if (ioctl(s->fd, CDIOCEJECT) < 0)
1865 perror("CDIOCEJECT");
1867 if (ioctl(s->fd, CDIOCCLOSE) < 0)
1868 perror("CDIOCCLOSE");
1874 static void cdrom_lock_medium(BlockDriverState *bs, bool locked)
1876 BDRVRawState *s = bs->opaque;
1880 if (ioctl(s->fd, (locked ? CDIOCPREVENT : CDIOCALLOW)) < 0) {
1882 * Note: an error can happen if the distribution automatically
1885 /* perror("CDROM_LOCKDOOR"); */
1889 static BlockDriver bdrv_host_cdrom = {
1890 .format_name = "host_cdrom",
1891 .protocol_name = "host_cdrom",
1892 .instance_size = sizeof(BDRVRawState),
1893 .bdrv_probe_device = cdrom_probe_device,
1894 .bdrv_file_open = cdrom_open,
1895 .bdrv_close = raw_close,
1896 .bdrv_reopen_prepare = raw_reopen_prepare,
1897 .bdrv_reopen_commit = raw_reopen_commit,
1898 .bdrv_reopen_abort = raw_reopen_abort,
1899 .bdrv_create = hdev_create,
1900 .create_options = raw_create_options,
1902 .bdrv_aio_readv = raw_aio_readv,
1903 .bdrv_aio_writev = raw_aio_writev,
1904 .bdrv_aio_flush = raw_aio_flush,
1906 .bdrv_truncate = raw_truncate,
1907 .bdrv_getlength = raw_getlength,
1908 .bdrv_get_allocated_file_size
1909 = raw_get_allocated_file_size,
1911 /* removable device support */
1912 .bdrv_is_inserted = cdrom_is_inserted,
1913 .bdrv_eject = cdrom_eject,
1914 .bdrv_lock_medium = cdrom_lock_medium,
1916 #endif /* __FreeBSD__ */
1918 #ifdef CONFIG_LINUX_AIO
1920 * Return the file descriptor for Linux AIO
1922 * This function is a layering violation and should be removed when it becomes
1923 * possible to call the block layer outside the global mutex. It allows the
1924 * caller to hijack the file descriptor so I/O can be performed outside the
1927 int raw_get_aio_fd(BlockDriverState *bs)
1935 if (bs->drv == bdrv_find_format("raw")) {
1939 /* raw-posix has several protocols so just check for raw_aio_readv */
1940 if (bs->drv->bdrv_aio_readv != raw_aio_readv) {
1950 #endif /* CONFIG_LINUX_AIO */
1952 static void bdrv_file_init(void)
1955 * Register all the drivers. Note that order is important, the driver
1956 * registered last will get probed first.
1958 bdrv_register(&bdrv_file);
1959 bdrv_register(&bdrv_host_device);
1961 bdrv_register(&bdrv_host_floppy);
1962 bdrv_register(&bdrv_host_cdrom);
1964 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1965 bdrv_register(&bdrv_host_cdrom);
1969 block_init(bdrv_file_init);