patch for the checkpointing paper

[Matthew Dillon]

    Please note that as per our previous discussions, we aren't going
    to be adding the 'cache' system call and you need to retool the
    calls you are currently making to just pass a flag down to the
    existing checkpoint/restore routines to tell them not to save/restore
    the descriptor set, and that you have to use the normal file path
    mechanism to create the files and not try to have the kernel do it
    itself, and we are not going to store a state variable in the proc
    structure, and a myrid of other issues which I have already discussed
    with you.  Most of these items should be handled strictly within userland,
    using file-backed shared memory to cache persistent data that you do
    not want to be restored and to track state.  The patch set cannot not be
    committed in its current form.

						-Matt