Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Block pull request

# gpg: Signature made Tue 15 Jul 2014 14:49:01 BST using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/block-pull-request:
  virtio-blk: dataplane: notify guest as a batch
  virtio-blk: data-plane: fix save/set .complete_request in start
  linux-aio: Fix laio resource leak

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>