Merge branch 'stable/cleancache.v13' into linux-next

* stable/cleancache.v13:
  mm: cleancache: Use __read_mostly as appropiate.
  mm: cleancache: report statistics via debugfs instead of sysfs.
  mm: zcache/tmem/cleancache: s/flush/invalidate/
  mm: cleancache: s/flush/invalidate/

diff --cc drivers/staging/zcache/zcache-main.c
Simple merge

diff --cc fs/block_dev.c
Simple merge

diff --cc fs/super.c
Simple merge

diff --cc mm/filemap.c
Simple merge