Merge branch 'work.sendfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Merge branch 'work.sendfile' of git://git./linux/kernel/git/viro/vfs

Pull sendfile updates from Al Viro:
 "Make sendfile() to pipe destination do the right thing, should make
  'fs/pipe: allow sendfile() to pipe again' redundant"

* 'work.sendfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  teach sendfile(2) to handle send-to-pipe directly
  take the guts of file-to-pipe splice into a helper function
  do_splice_to(): move the logics for limiting the read length in