Pull filesystem-dax updates from Dan Williams:

 - Fix handling of PMD-sized entries in the Xarray that lead to a crash
   scenario

 - Miscellaneous cleanups and small fixes

* tag 'fsdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Flush partial PMDs correctly
  fs/dax: NIT fix comment regarding start/end vs range
  fs/dax: Convert to use vmf_error()