linux-vybrid_public/fs/nfs/fscache.c

/* NFS filesystem cache interface
 *
 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_fs_sb.h>
#include <linux/in6.h>
#include <linux/seq_file.h>

#include "internal.h"
#include "fscache.h"

#define NFSDBG_FACILITY		NFSDBG_FSCACHE

/*
 * Get the per-client index cookie for an NFS client if the appropriate mount
 * flag was set
 * - We always try and get an index cookie for the client, but get filehandle
 *   cookies on a per-superblock basis, depending on the mount flags
 */
void nfs_fscache_get_client_cookie(struct nfs_client *clp)
{
	/* create a cache index for looking up filehandles */
	clp->fscache = fscache_acquire_cookie(nfs_fscache_netfs.primary_index,
					      &nfs_fscache_server_index_def,
					      clp);
	dfprintk(FSCACHE, "NFS: get client cookie (0x%p/0x%p)\n",
		 clp, clp->fscache);
}

/*
 * Dispose of a per-client cookie
 */
void nfs_fscache_release_client_cookie(struct nfs_client *clp)
{
	dfprintk(FSCACHE, "NFS: releasing client cookie (0x%p/0x%p)\n",
		 clp, clp->fscache);

	fscache_relinquish_cookie(clp->fscache, 0);
	clp->fscache = NULL;
}