Pull vfs updates from Al Viro:
"overlayfs merge + leak fix for d_splice_alias() failure exits"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
overlayfs: embed middle into overlay_readdir_data
overlayfs: embed root into overlay_readdir_data
overlayfs: make ovl_cache_entry->name an array instead of pointer
overlayfs: don't hold ->i_mutex over opening the real directory
fix inode leaks on d_splice_alias() failure exits
fs: limit filesystem stacking depth
overlay: overlay filesystem documentation
overlayfs: implement show_options
overlayfs: add statfs support
overlay filesystem
shmem: support RENAME_WHITEOUT
ext4: support RENAME_WHITEOUT
vfs: add RENAME_WHITEOUT
vfs: add whiteout support
vfs: export check_sticky()
vfs: introduce clone_private_mount()
vfs: export __inode_permission() to modules
vfs: export do_splice_direct() to modules
vfs: add i_op->dentry_open()