A pinned inode may in theory end up filling memory with cached ACCESS
calls. This patch ensures that the VM may shrink away the cache in these
particular cases.
The shrinker works by iterating through the list of inodes on the global
nfs_access_lru_list, and removing the least recently used access
cache entry until it is done (or until the entire cache is empty).
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fs/built-in.o:(__param+0x20): undefined reference to `nfs_idmap_cache_timeout'
fs/built-in.o:(__param+0x48): undefined reference to `nfs_callback_set_tcpport'

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andreas Gruenbacher <agruen@suse.de>
Cc: Andy Adamson <andros@citi.umich.edu>
Cc: Chuck Lever <cel@netapp.com>
Cc: David Howells <dhowells@redhat.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Manoj Naik <manoj@almaden.ibm.com>
Cc: Marc Eshel <eshel@almaden.ibm.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

As fs/nfs/inode.c is rather large, heterogenous and unwieldy, the attached
patch splits it up into a number of files:

 (*) fs/nfs/inode.c

     Strictly inode specific functions.

 (*) fs/nfs/super.c

     Superblock management functions for NFS and NFS4, normal access, clones
     and referrals.  The NFS4 superblock functions _could_ move out into a
     separate conditionally compiled file, but it's probably not worth it as
     there're so many common bits.

 (*) fs/nfs/namespace.c

     Some namespace-specific functions have been moved here.

 (*) fs/nfs/nfs4namespace.c

     NFS4-specific namespace functions (this could be merged into the previous
     file).  This file is conditionally compiled.

 (*) fs/nfs/internal.h

     Inter-file declarations, plus a few simple utility functions moved from
     fs/nfs/inode.c.

     Additionally, all the in-.c-file externs have been moved here, and those
     files they were moved from now includes this file.

For the most part, the functions have not been changed, only some multiplexor
functions have changed significantly.

I've also:

 (*) Added some extra banner comments above some functions.

 (*) Rearranged the function order within the files to be more logical and
     better grouped (IMO), though someone may prefer a different order.

 (*) Reduced the number of #ifdefs in .c files.

 (*) Added missing __init and __exit directives.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>