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

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

# gpg: Signature made Fri 14 Nov 2014 11:05:54 GMT 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:
  vmdk: Leave bdi intact if -ENOTSUP in vmdk_get_info
  block: Fix max nb_sectors in bdrv_make_zero
  ahci: factor out FIS decomposition from handle_cmd
  ahci: Check cmd_fis[1] more explicitly
  ahci: Reorder error cases in handle_cmd
  ahci: Fix FIS decomposition
  ahci: add is_ncq predicate helper
  ide: Correct handling of malformed/short PRDTs
  ahci: unify sglist preparation
  ide: repair PIO transfers for cases where nsector > 1
  ahci: Fix byte count regression for ATAPI/PIO

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