NFS: Split fs/nfs/inode.c

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: David Howells <dhowells@redhat.com>
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 3c72b0c..402005c 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -892,7 +892,7 @@
  * nfs_init_directcache - create a slab cache for nfs_direct_req structures
  *
  */
-int nfs_init_directcache(void)
+int __init nfs_init_directcache(void)
 {
 	nfs_direct_cachep = kmem_cache_create("nfs_direct_cache",
 						sizeof(struct nfs_direct_req),
@@ -906,10 +906,10 @@
 }
 
 /**
- * nfs_init_directcache - destroy the slab cache for nfs_direct_req structures
+ * nfs_destroy_directcache - destroy the slab cache for nfs_direct_req structures
  *
  */
-void nfs_destroy_directcache(void)
+void __exit nfs_destroy_directcache(void)
 {
 	if (kmem_cache_destroy(nfs_direct_cachep))
 		printk(KERN_INFO "nfs_direct_cache: not all structures were freed\n");