Merge tag 'for-f2fs-4.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeu...

Pull f2fs fixes from Jaegeuk Kim:

 - fix performance regression reported by lkp-rebot

 - fix potential data lost after power-cut due to SSR reallocation

* tag 'for-f2fs-4.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: combine nat_bits and free_nid_bitmap cache
  f2fs: skip scanning free nid bitmap of full NAT blocks
  f2fs: use __set{__clear}_bit_le
  f2fs: declare static functions
  f2fs: don't overwrite node block by SSR