Merge tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull dcache updates from Al Viro:

 - d_alloc_parallel() API change (Neil's with my changes)

 - NORCU fixes

 - Reorganization and simplification of dentry eviction logic

 - Simplifying rcu_read_lock() scopes in fs/dcache.c

 - Secondary roots work - getting rid of NFS fake root dentries and
   dealing with remaining shrink_dcache_for_umount() and
   shrink_dentry_list() races

 - making cursors NORCU (surprisingly easy)

* tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (22 commits)
  make cursors NORCU
  nfs: get rid of fake root dentries
  wind ->s_roots via ->d_sib instead of ->d_hash
  shrink_dentry_tree(): unify the calls of shrink_dentry_list()
  shrinking rcu_read_lock() scope in d_alloc_parallel()
  d_walk(): shrink rcu_read_lock() scope
  document dentry_kill()
  adjust calling conventions of lock_for_kill(), fold __dentry_kill() into dentry_kill()
  Document rcu_read_lock() use in select_collect2()
  Shift rcu_read_{,un}lock() inside fast_dput()
  simplify safety for lock_for_kill() slowpath
  fold lock_for_kill() and __dentry_kill() into common helper
  fold lock_for_kill() into shrink_kill()
  shrink_dentry_list(): start with removing from shrink list
  d_prune_aliases(): make sure to skip NORCU aliases
  kill d_dispose_if_unused()
  make to_shrink_list() return whether it has moved dentry to list
  select_collect(): ignore dentries on shrink lists if they have positive refcounts
  find_acceptable_alias(): skip NORCU aliases with zero refcount
  fix a race between d_find_any_alias() and final dput() of NORCU dentries
  ...

diff --cc Documentation/filesystems/porting.rst
Simple merge

diff --cc fs/dcache.c
Simple merge

diff --cc fs/file_table.c
Simple merge

diff --cc fs/namei.c
Simple merge

diff --cc fs/nfs/dir.c
Simple merge

diff --cc fs/proc/base.c
Simple merge

diff --cc fs/super.c
Simple merge

diff --cc include/linux/fs/super_types.h
Simple merge

diff --cc include/linux/nfs_xdr.h
Simple merge