Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - fix an uninitialised pointer Oops in the writeback error path
   - fix a bogus warning (and early exit from the loop) in nfs_generic_pgio()

  Features:
   - Add NFSv4.2 SEEK feature and client support for lseek(SEEK_HOLE/SEEK_DATA)

  Other fixes:
   - pnfs: replace broken pnfs_put_lseg_async
   - Remove dead prototype for nfs4_insert_deviceid_node"

* tag 'nfs-for-3.18-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Fix a bogus warning in nfs_generic_pgio
  NFS: Fix an uninitialised pointer Oops in the writeback error path
  NFSv4.1/pnfs: replace broken pnfs_put_lseg_async
  NFSv4: Remove dead prototype for nfs4_insert_deviceid_node()
  NFS: Implement SEEK