Pull overlayfs updates from Miklos Szeredi:
"This work from Amir introduces the inodes index feature, which
provides:
- hardlinks are not broken on copy up
- infrastructure for overlayfs NFS export
This also fixes constant st_ino for samefs case for lower hardlinks"
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (33 commits)
ovl: mark parent impure and restore timestamp on ovl_link_up()
ovl: document copying layers restrictions with inodes index
ovl: cleanup orphan index entries
ovl: persistent overlay inode nlink for indexed inodes
ovl: implement index dir copy up
ovl: move copy up lock out
ovl: rearrange copy up
ovl: add flag for upper in ovl_entry
ovl: use struct copy_up_ctx as function argument
ovl: base tmpfile in workdir too
ovl: factor out ovl_copy_up_inode() helper
ovl: extract helper to get temp file in copy up
ovl: defer upper dir lock to tempfile link
ovl: hash overlay non-dir inodes by copy up origin
ovl: cleanup bad and stale index entries on mount
ovl: lookup index entry for copy up origin
ovl: verify index dir matches upper dir
ovl: verify upper root dir matches lower root dir
ovl: introduce the inodes index dir feature
ovl: generalize ovl_create_workdir()
...