diff options
| -rw-r--r-- | block/cow.c | 2 | ||||
| -rw-r--r-- | block/raw-posix.c | 2 | ||||
| -rw-r--r-- | cutils.c | 16 | ||||
| -rw-r--r-- | qemu-common.h | 1 |
4 files changed, 19 insertions, 2 deletions
diff --git a/block/cow.c b/block/cow.c index 84818f1034..a70854e631 100644 --- a/block/cow.c +++ b/block/cow.c @@ -258,7 +258,7 @@ static int cow_create(const char *filename, QEMUOptionParameter *options) static void cow_flush(BlockDriverState *bs) { BDRVCowState *s = bs->opaque; - fsync(s->fd); + qemu_fdatasync(s->fd); } static QEMUOptionParameter cow_create_options[] = { diff --git a/block/raw-posix.c b/block/raw-posix.c index 2125d67a5f..2ebc88f004 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -723,7 +723,7 @@ static int raw_create(const char *filename, QEMUOptionParameter *options) static void raw_flush(BlockDriverState *bs) { BDRVRawState *s = bs->opaque; - fsync(s->fd); + qemu_fdatasync(s->fd); } @@ -115,6 +115,22 @@ int qemu_fls(int i) return 32 - clz32(i); } +/* + * Make sure data goes on disk, but if possible do not bother to + * write out the inode just for timestamp updates. + * + * Unfortunately even in 2009 many operating systems do not support + * fdatasync and have to fall back to fsync. + */ +int qemu_fdatasync(int fd) +{ +#ifdef _POSIX_SYNCHRONIZED_IO + return fdatasync(fd); +#else + return fsync(fd); +#endif +} + /* io vectors */ void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint) diff --git a/qemu-common.h b/qemu-common.h index f3cfb683ea..12e7dd0ada 100644 --- a/qemu-common.h +++ b/qemu-common.h @@ -114,6 +114,7 @@ int stristart(const char *str, const char *val, const char **ptr); int qemu_strnlen(const char *s, int max_len); time_t mktimegm(struct tm *tm); int qemu_fls(int i); +int qemu_fdatasync(int fd); /* path.c */ void init_paths(const char *prefix); |