[git pull] device mapper changes for 4.18

[Mike Snitzer <snitzer@redhat.com>]

Hi Linus,

I've based on linux-block because the new dm-writecache target that is
in this pull needed to be updated to use the new bioset_init/mempool_init
interfaces.

The following changes since commit 04c4950d5b373ba712d928592e05e73510785bca:

  block: fixup bioset_integrity_create() call (2018-05-30 18:51:21 -0600)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git tags/for-4.18/dm-changes

for you to fetch changes up to 1be8d9c3da01a08d1d92064abb91e4610115db11:

  dm: add writecache target (2018-05-31 08:11:42 -0400)

Please pull, thanks!
Mike

----------------------------------------------------------------
- Export 2 swait symbols for use by the new DM writecache target.

- Add DM writecache target that offers writeback caching to persistent
  memory or SSD.

- Small DM core change to give context in error message for why a DM
  table type transition wasn't allowed.

----------------------------------------------------------------
Mike Snitzer (1):
      dm: report which conflicting type caused error during table_load()

Mikulas Patocka (2):
      swait: export symbols __prepare_to_swait and __finish_swait
      dm: add writecache target

 Documentation/device-mapper/writecache.txt |   68 +
 drivers/md/Kconfig                         |   11 +
 drivers/md/Makefile                        |    1 +
 drivers/md/dm-ioctl.c                      |    3 +-
 drivers/md/dm-writecache.c                 | 2285 ++++++++++++++++++++++++++++
 kernel/sched/swait.c                       |    2 +
 6 files changed, 2369 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/device-mapper/writecache.txt
 create mode 100644 drivers/md/dm-writecache.c