tree ecf430017866c7275158d2d99f6312972e277a1e
parent 6bf3ee07ff55aa795010a8e071826f38e9a26112
author Kevin Wolf <kwolf@redhat.com> 1358360751 +0100
committer Stefan Hajnoczi <stefanha@redhat.com> 1358416302 +0100

aio: Fix return value of aio_poll()

aio_poll() must return true if any work is still pending, even if it
didn't make progress, so that bdrv_drain_all() doesn't stop waiting too
early. The possibility of stopping early occasionally lead to a failed
assertion in bdrv_drain_all(), when some in-flight request was missed
and the function didn't really drain all requests.

In order to make that change, the return value as specified in the
function comment must change for blocking = false; fortunately, the
return value of blocking = false callers is only used in test cases, so
this change shouldn't cause any trouble.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>