Merge tag 'for-4.12/dm-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - a revert of a DM mirror commit that has proven to make the code prone
   to crash

 - a DM io reference count fix that resolves a NULL pointer seen when
   issuing discards to a DM mirror target's device whose mirror legs do
   not all support discards

 - a couple DM integrity fixes

* tag 'for-4.12/dm-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm io: fix duplicate bio completion due to missing ref count
  dm integrity: fix to not disable/enable interrupts from interrupt context
  Revert "dm mirror: use all available legs on multiple failures"
  dm integrity: reject mappings too large for device