Merge branch 'md-next' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md...

Pull MD changes from Song:

"Summary:
 1. Fix race condition in md_ioctl(), by Dae R. Jeong;
 2. Initialize read_slot properly for raid10, by Kevin Vigor;
 3. Code cleanup, by Pankaj Gupta;
 4. md-cluster resync/reshape fix, by Zhao Heming."

* 'md-next' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md:
  md/cluster: fix deadlock when node is doing resync job
  md/cluster: block reshape with remote resync job
  md: use current request time as base for ktime comparisons
  md: add comments in md_flush_request()
  md: improve variable names in md_flush_request()
  md/raid10: initialize r10_bio->read_slot before use.
  md: fix a warning caused by a race between concurrent md_ioctl()s