[git pull] vfs: dcache work

[Al Viro <viro@zeniv.linux.org.uk>]

The following changes since commit e43ffb69e0438cddd72aaa30898b4dc446f664f8:

  Linux 7.1-rc6 (2026-05-31 15:14:24 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git tags/pull-dcache

for you to fetch changes up to 3df5153c5f123d6018c82a24341ccd99c79d64a0:

  make cursors NORCU (2026-06-05 00:34:56 -0400)

----------------------------------------------------------------
dentry memory safety stuff

 * d_alloc_parallel() API change (Neil's with my changes).
 * NORCU fixes.
 * Reorganization and simplification of dentry eviction logics.
 * 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()/shrink_dentry_list()
 races.
 * making cursors NORCU (surprisingly easy)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

----------------------------------------------------------------
Al Viro (21):
      alloc_path_pseudo(): make sure we don't end up with NORCU dentries for directories
      fix a race between d_find_any_alias() and final dput() of NORCU dentries
      find_acceptable_alias(): skip NORCU aliases with zero refcount
      select_collect(): ignore dentries on shrink lists if they have positive refcounts
      make to_shrink_list() return whether it has moved dentry to list
      kill d_dispose_if_unused()
      d_prune_aliases(): make sure to skip NORCU aliases
      shrink_dentry_list(): start with removing from shrink list
      fold lock_for_kill() into shrink_kill()
      fold lock_for_kill() and __dentry_kill() into common helper
      simplify safety for lock_for_kill() slowpath
      Shift rcu_read_{,un}lock() inside fast_dput()
      Document rcu_read_lock() use in select_collect2()
      adjust calling conventions of lock_for_kill(), fold __dentry_kill() into dentry_kill()
      document dentry_kill()
      d_walk(): shrink rcu_read_lock() scope
      shrinking rcu_read_lock() scope in d_alloc_parallel()
      shrink_dentry_tree(): unify the calls of shrink_dentry_list()
      wind ->s_roots via ->d_sib instead of ->d_hash
      nfs: get rid of fake root dentries
      make cursors NORCU

NeilBrown (1):
      VFS: use wait_var_event for waiting in d_alloc_parallel()

 Documentation/filesystems/porting.rst |  17 ++
 fs/afs/dir_silly.c                    |   4 +-
 fs/dcache.c                           | 549 ++++++++++++++++++++--------------
 fs/exportfs/expfs.c                   |   9 +-
 fs/file_table.c                       |   2 +
 fs/fuse/dir.c                         |   2 +-
 fs/fuse/readdir.c                     |   3 +-
 fs/namei.c                            |   6 +-
 fs/nfs/dir.c                          |   6 +-
 fs/nfs/getroot.c                      |  35 +--
 fs/nfs/unlink.c                       |   3 +-
 fs/proc/base.c                        |   3 +-
 fs/proc/proc_sysctl.c                 |   3 +-
 fs/smb/client/readdir.c               |   3 +-
 fs/super.c                            |   1 +
 include/linux/dcache.h                |  31 +-
 include/linux/fs/super_types.h        |   3 +-
 include/linux/nfs_xdr.h               |   1 -
 18 files changed, 387 insertions(+), 294 deletions(-)