/* NFS FS-Cache index structure definition
*
* 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 "internal.h"
#include "fscache.h"
#define NFSDBG_FACILITY NFSDBG_FSCACHE
/*
* Define the NFS filesystem for FS-Cache. Upon registration FS-Cache sticks
* the cookie for the top-level index object for NFS into here. The top-level
* index can than have other cache objects inserted into it.
*/
struct fscache_netfs nfs_fscache_netfs = {
.name = "nfs",
.version = 0,
};
/*
* Register NFS for caching
*/
int nfs_fscache_register(void)
{
return fscache_register_netfs(&nfs_fscache_netfs);
}
/*
* Unregister NFS for caching
*/
void nfs_fscache_unregister(void)
{
fscache_unregister_netfs(&nfs_fscache_netfs);
}
/*
* Layout of the key for an NFS server cache object.
*/
struct nfs_server_key {
uint16_t nfsversion; /* NFS protocol version */
uint16_t family; /* address family */
uint16_t port; /* IP port */
union {
struct in_addr ipv4_addr; /* IPv4 address */
struct in6_addr ipv6_addr; /* IPv6 address */
} addr[0];
};
/*
* Generate a key to describe a server in the main NFS index
* - We return the length of the key, or 0 if we can't generate one
*/
static uint16_t nfs_server_get_key(const void *cookie_netfs_data,
void *buffer, uint16_t bufmax)
{
const struct nfs_client *clp = cookie_netfs_data;
const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;
struct nfs_server_key *key = buffer;
uint16_t len = sizeof(struct nfs_server_key);
key->nfsversion = clp->rpc_ops->version;
key->family = clp->cl_addr.ss_family;
memset(key, 0, len);
switch (clp->cl_addr.ss_family) {
case AF_INET:
key->port = sin->sin_port;
key->addr[0].ipv4_addr = sin->sin_addr;
len += sizeof(key->addr[0].ipv4_addr);
break;
case AF_INET6:
key->port = sin6->sin6_port;
key->addr[0].ipv6_addr = sin6->sin6_addr;
len += sizeof(key->addr[0].ipv6_addr);
break;
default:
printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
clp->cl_addr.ss_family);
len = 0;
break;
}
return len;
}
/*
* Define the server object for FS-Cache. This is used to describe a server
* object to fscache_acquire_cookie(). It is keyed by the NFS protocol and
* server address parameters.
*/
const struct fscache_cookie_def nfs_fscache_server_index_def = {
.name = "NFS.server",
.type = FSCACHE_COOKIE_TYPE_INDEX,
.get_key = nfs_server_get_key,
};
/*
* Generate a key to describe a superblock key in the main NFS index
*/
static uint16_t nfs_super_get_key(const void *cookie_netfs_data,
void *buffer, uint16_t bufmax)
{
const struct nfs_fscache_key *key;
const struct nfs_server *nfss = cookie_netfs_data;
uint16_t len;
key = nfss->fscache_key;
len = sizeof(key->key) + key->key.uniq_len;
if (len > bufmax) {
len = 0;
} else {
memcpy(buffer, &key->key, sizeof(key->key));
memcpy(buffer + sizeof(key->key),
key->key.uniquifier, key->key.uniq_len);
}
return len;
}
/*
* Define the superblock object for FS-Cache. This is used to describe a
* superblock object to fscache_acquire_cookie(). It is keyed by all the NFS
* parameters that might cause a separate superblock.
*/
const struct fscache_cookie_def nfs_fscache_super_index_def = {
.name = "NFS.super",
.type = FSCACHE_COOKIE_TYPE_INDEX,
.get_key = nfs_super_get_key,
};
