Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm crypt: add merge
  dm table: remove merge_bvec sector restriction
  dm: linear add merge
  dm: introduce merge_bvec_fn
  dm snapshot: use per device mempools
  dm snapshot: fix race during exception creation
  dm snapshot: track snapshot reads
  dm mpath: fix test for reinstate_path
  dm mpath: return parameter error
  dm io: remove struct padding
  dm log: make dm_dirty_log init and exit static
  dm mpath: free path selector on invalid args