block: convert qemu_aio_flush() calls to bdrv_drain_all()
Many places in QEMU call qemu_aio_flush() to complete all pending
asynchronous I/O. Most of these places actually want to drain all block
requests but there is no block layer API to do so.
This patch introduces the bdrv_drain_all() API to wait for requests
across all BlockDriverStates to complete. As a bonus we perform checks
after qemu_aio_wait() to ensure that requests really have finished.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/savevm.c b/savevm.c
index f53cd4c..0443554 100644
--- a/savevm.c
+++ b/savevm.c
@@ -2104,7 +2104,7 @@
}
/* Flush all IO requests so they don't interfere with the new state. */
- qemu_aio_flush();
+ bdrv_drain_all();
bs = NULL;
while ((bs = bdrv_next(bs))) {
