int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
- int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs);
int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs,
int64_t sector_num, int nb_sectors);
+ /*
+ * Flushes all data that was already written to the OS all the way down to
+ * the disk (for example raw-posix calls fsync()).
+ */
+ int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);
+
+ /*
+ * Flushes all internal caches to the OS. The data may still sit in a
+ * writeback cache of the host OS, but it will survive a crash of the qemu
+ * process.
+ */
+ int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);
+
int (*bdrv_aio_multiwrite)(BlockDriverState *bs, BlockRequest *reqs,
int num_reqs);
int (*bdrv_merge_requests)(BlockDriverState *bs, BlockRequest* a,