[GIT PULL] dax fixes for 4.20-rc6

["Williams, Dan J" <dan.j.williams@intel.com>]

Hi Linus, please pull from:

  git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm tags/dax-fixes-4.20-rc6

...to receive the last of the known regression fixes and fallout from
the Xarray conversion of the filesystem-dax implementation. On the path
to debugging why the dax memory-failure injection test started failing
after the Xarray conversion a couple more fixes for the
dax_lock_mapping_entry(), now called dax_lock_page(), surfaced. Those
plus the bug that started the hunt are now addressed. These patches
have appeared in a -next release with no issues reported.

Note the touches to mm/memory-failure.c are just the conversion to the
new function signature for dax_lock_page().

---

The following changes since commit 2e6e902d185027f8e3cb8b7305238f7e35d6a436:

  Linux 4.20-rc4 (2018-11-25 14:19:31 -0800)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm tags/dax-fixes-4.20-rc6

for you to fetch changes up to 27359fd6e5f3c5db8fe544b63238b6170e8806d8:

  dax: Fix unlock mismatch with updated API (2018-12-04 21:32:00 -0800)

----------------------------------------------------------------
dax fixes 4.20-rc6

* Fix the Xarray conversion of fsdax to properly handle
dax_lock_mapping_entry() in the presense of pmd entries.

* Fix inode destruction racing a new lock request.

----------------------------------------------------------------
Matthew Wilcox (3):
      dax: Check page->mapping isn't NULL
      dax: Don't access a freed inode
      dax: Fix unlock mismatch with updated API

 fs/dax.c            | 55 ++++++++++++++++++++++++++++++++++++-----------------
 include/linux/dax.h | 14 ++++++++------
 mm/memory-failure.c |  6 ++++--
 3 files changed, 50 insertions(+), 25 deletions(-)