Merge branch 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

* 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (28 commits)
  pnfsblock: write_pagelist handle zero invalid extents
  pnfsblock: note written INVAL areas for layoutcommit
  pnfsblock: bl_write_pagelist
  pnfsblock: bl_read_pagelist
  pnfsblock: cleanup_layoutcommit
  pnfsblock: encode_layoutcommit
  pnfsblock: merge rw extents
  pnfsblock: add extent manipulation functions
  pnfsblock: bl_find_get_extent
  pnfsblock: xdr decode pnfs_block_layout4
  pnfsblock: call and parse getdevicelist
  pnfsblock: merge extents
  pnfsblock: lseg alloc and free
  pnfsblock: remove device operations
  pnfsblock: add device operations
  pnfsblock: basic extent code
  pnfsblock: use pageio_ops api
  pnfsblock: add blocklayout Kconfig option, Makefile, and stubs
  pnfs: cleanup_layoutcommit
  pnfs: ask for layout_blksize and save it in nfs_server
  ...