Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches (v2)

# gpg: Signature made Mon 14 Sep 2015 15:56:54 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (23 commits)
  qcow2: Make qcow2_alloc_bytes() more explicit
  vmdk: Fix next_cluster_sector for compressed write
  iotests: Add test for checking large image files
  qcow2: Make size_to_clusters() return uint64_t
  qemu-iotests: More qcow2 reopen tests
  qemu-iotests: Reopen qcow2 with lazy-refcounts change
  qcow2: Support updating driver-specific options in reopen
  qcow2: Make qcow2_update_options() suitable for transactions
  qcow2: Fix memory leak in qcow2_update_options() error path
  qcow2: Leave s unchanged on qcow2_update_options() failure
  qcow2: Move rest of option handling to qcow2_update_options()
  qcow2: Move qcow2_update_options() call up
  qcow2: Factor out qcow2_update_options()
  qcow2: Improve error message
  qemu-io: Add command 'reopen'
  qemu-io: Remove duplicate 'open' error message
  block: Allow specifying driver-specific options to reopen
  qcow2: Rename BDRVQcowState to BDRVQcow2State
  block: Drop bdrv_find_whitelisted_format()
  block: Drop drv parameter from bdrv_fill_options()
  ...

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