linux/fs/nfs/client.c
David Howells 5006a76cca NFS: Eliminate client_sys in favour of cl_rpcclient
Eliminate nfs_server::client_sys in favour of nfs_client::cl_rpcclient as we
only really need one per server that we're talking to since it doesn't have any
security on it.

The retransmission management variables are also moved to the common struct as
they're required to set up the cl_rpcclient connection.

The NFS2/3 client and client_acl connections are thenceforth derived by cloning
the cl_rpcclient connection and post-applying the authorisation flavour.

The code for setting up the initial common connection has been moved to
client.c as nfs_create_rpc_client().  All the NFS program definition tables are
also moved there as that's where they're now required rather than super.c.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:36 -04:00

432 lines
9.8 KiB
C

/* client.c: NFS client sharing and management code
*
* Copyright (C) 2006 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 License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/metrics.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/lockd/bind.h>
#include <linux/smp_lock.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/nfs_idmap.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include <linux/nfs_xdr.h>
#include <asm/system.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "iostat.h"
#include "internal.h"
#define NFSDBG_FACILITY NFSDBG_CLIENT
static DEFINE_SPINLOCK(nfs_client_lock);
static LIST_HEAD(nfs_client_list);
static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
/*
* RPC cruft for NFS
*/
static struct rpc_version *nfs_version[5] = {
[2] = &nfs_version2,
#ifdef CONFIG_NFS_V3
[3] = &nfs_version3,
#endif
#ifdef CONFIG_NFS_V4
[4] = &nfs_version4,
#endif
};
struct rpc_program nfs_program = {
.name = "nfs",
.number = NFS_PROGRAM,
.nrvers = ARRAY_SIZE(nfs_version),
.version = nfs_version,
.stats = &nfs_rpcstat,
.pipe_dir_name = "/nfs",
};
struct rpc_stat nfs_rpcstat = {
.program = &nfs_program
};
#ifdef CONFIG_NFS_V3_ACL
static struct rpc_stat nfsacl_rpcstat = { &nfsacl_program };
static struct rpc_version * nfsacl_version[] = {
[3] = &nfsacl_version3,
};
struct rpc_program nfsacl_program = {
.name = "nfsacl",
.number = NFS_ACL_PROGRAM,
.nrvers = ARRAY_SIZE(nfsacl_version),
.version = nfsacl_version,
.stats = &nfsacl_rpcstat,
};
#endif /* CONFIG_NFS_V3_ACL */
/*
* Allocate a shared client record
*
* Since these are allocated/deallocated very rarely, we don't
* bother putting them in a slab cache...
*/
static struct nfs_client *nfs_alloc_client(const char *hostname,
const struct sockaddr_in *addr,
int nfsversion)
{
struct nfs_client *clp;
int error;
if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
goto error_0;
error = rpciod_up();
if (error < 0) {
dprintk("%s: couldn't start rpciod! Error = %d\n",
__FUNCTION__, error);
__set_bit(NFS_CS_RPCIOD, &clp->cl_res_state);
goto error_1;
}
if (nfsversion == 4) {
if (nfs_callback_up() < 0)
goto error_2;
__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
}
atomic_set(&clp->cl_count, 1);
clp->cl_cons_state = NFS_CS_INITING;
clp->cl_nfsversion = nfsversion;
memcpy(&clp->cl_addr, addr, sizeof(clp->cl_addr));
if (hostname) {
clp->cl_hostname = kstrdup(hostname, GFP_KERNEL);
if (!clp->cl_hostname)
goto error_3;
}
INIT_LIST_HEAD(&clp->cl_superblocks);
clp->cl_rpcclient = ERR_PTR(-EINVAL);
#ifdef CONFIG_NFS_V4
init_rwsem(&clp->cl_sem);
INIT_LIST_HEAD(&clp->cl_delegations);
INIT_LIST_HEAD(&clp->cl_state_owners);
INIT_LIST_HEAD(&clp->cl_unused);
spin_lock_init(&clp->cl_lock);
INIT_WORK(&clp->cl_renewd, nfs4_renew_state, clp);
rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
clp->cl_boot_time = CURRENT_TIME;
clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
#endif
return clp;
error_3:
nfs_callback_down();
__clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
error_2:
rpciod_down();
__clear_bit(NFS_CS_RPCIOD, &clp->cl_res_state);
error_1:
kfree(clp);
error_0:
return NULL;
}
/*
* Destroy a shared client record
*/
static void nfs_free_client(struct nfs_client *clp)
{
dprintk("--> nfs_free_client(%d)\n", clp->cl_nfsversion);
#ifdef CONFIG_NFS_V4
if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state)) {
while (!list_empty(&clp->cl_unused)) {
struct nfs4_state_owner *sp;
sp = list_entry(clp->cl_unused.next,
struct nfs4_state_owner,
so_list);
list_del(&sp->so_list);
kfree(sp);
}
BUG_ON(!list_empty(&clp->cl_state_owners));
nfs_idmap_delete(clp);
}
#endif
/* -EIO all pending I/O */
if (!IS_ERR(clp->cl_rpcclient))
rpc_shutdown_client(clp->cl_rpcclient);
if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
nfs_callback_down();
if (__test_and_clear_bit(NFS_CS_RPCIOD, &clp->cl_res_state))
rpciod_down();
kfree(clp->cl_hostname);
kfree(clp);
dprintk("<-- nfs_free_client()\n");
}
/*
* Release a reference to a shared client record
*/
void nfs_put_client(struct nfs_client *clp)
{
dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
list_del(&clp->cl_share_link);
spin_unlock(&nfs_client_lock);
BUG_ON(!list_empty(&clp->cl_superblocks));
nfs_free_client(clp);
}
}
/*
* Find a client by address
* - caller must hold nfs_client_lock
*/
static struct nfs_client *__nfs_find_client(const struct sockaddr_in *addr, int nfsversion)
{
struct nfs_client *clp;
list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
/* Different NFS versions cannot share the same nfs_client */
if (clp->cl_nfsversion != nfsversion)
continue;
if (memcmp(&clp->cl_addr.sin_addr, &addr->sin_addr,
sizeof(clp->cl_addr.sin_addr)) != 0)
continue;
if (clp->cl_addr.sin_port == addr->sin_port)
goto found;
}
return NULL;
found:
atomic_inc(&clp->cl_count);
return clp;
}
/*
* Find a client by IP address and protocol version
* - returns NULL if no such client
*/
struct nfs_client *nfs_find_client(const struct sockaddr_in *addr, int nfsversion)
{
struct nfs_client *clp;
spin_lock(&nfs_client_lock);
clp = __nfs_find_client(addr, nfsversion);
spin_unlock(&nfs_client_lock);
BUG_ON(clp->cl_cons_state == 0);
return clp;
}
/*
* Look up a client by IP address and protocol version
* - creates a new record if one doesn't yet exist
*/
struct nfs_client *nfs_get_client(const char *hostname,
const struct sockaddr_in *addr,
int nfsversion)
{
struct nfs_client *clp, *new = NULL;
int error;
dprintk("--> nfs_get_client(%s,"NIPQUAD_FMT":%d,%d)\n",
hostname ?: "", NIPQUAD(addr->sin_addr),
addr->sin_port, nfsversion);
/* see if the client already exists */
do {
spin_lock(&nfs_client_lock);
clp = __nfs_find_client(addr, nfsversion);
if (clp)
goto found_client;
if (new)
goto install_client;
spin_unlock(&nfs_client_lock);
new = nfs_alloc_client(hostname, addr, nfsversion);
} while (new);
return ERR_PTR(-ENOMEM);
/* install a new client and return with it unready */
install_client:
clp = new;
list_add(&clp->cl_share_link, &nfs_client_list);
spin_unlock(&nfs_client_lock);
dprintk("--> nfs_get_client() = %p [new]\n", clp);
return clp;
/* found an existing client
* - make sure it's ready before returning
*/
found_client:
spin_unlock(&nfs_client_lock);
if (new)
nfs_free_client(new);
if (clp->cl_cons_state == NFS_CS_INITING) {
DECLARE_WAITQUEUE(myself, current);
add_wait_queue(&nfs_client_active_wq, &myself);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
if (signal_pending(current) ||
clp->cl_cons_state > NFS_CS_READY)
break;
schedule();
}
remove_wait_queue(&nfs_client_active_wq, &myself);
if (signal_pending(current)) {
nfs_put_client(clp);
return ERR_PTR(-ERESTARTSYS);
}
}
if (clp->cl_cons_state < NFS_CS_READY) {
error = clp->cl_cons_state;
nfs_put_client(clp);
return ERR_PTR(error);
}
dprintk("--> nfs_get_client() = %p [share]\n", clp);
return clp;
}
/*
* Mark a server as ready or failed
*/
void nfs_mark_client_ready(struct nfs_client *clp, int state)
{
clp->cl_cons_state = state;
wake_up_all(&nfs_client_active_wq);
}
/*
* Initialise the timeout values for a connection
*/
static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
unsigned int timeo, unsigned int retrans)
{
to->to_initval = timeo * HZ / 10;
to->to_retries = retrans;
if (!to->to_retries)
to->to_retries = 2;
switch (proto) {
case IPPROTO_TCP:
if (!to->to_initval)
to->to_initval = 60 * HZ;
if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
to->to_initval = NFS_MAX_TCP_TIMEOUT;
to->to_increment = to->to_initval;
to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
to->to_exponential = 0;
break;
case IPPROTO_UDP:
default:
if (!to->to_initval)
to->to_initval = 11 * HZ / 10;
if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
to->to_initval = NFS_MAX_UDP_TIMEOUT;
to->to_maxval = NFS_MAX_UDP_TIMEOUT;
to->to_exponential = 1;
break;
}
}
/*
* Create an RPC client handle
*/
int nfs_create_rpc_client(struct nfs_client *clp, int proto,
unsigned int timeo,
unsigned int retrans,
rpc_authflavor_t flavor)
{
struct rpc_timeout timeparms;
struct rpc_xprt *xprt = NULL;
struct rpc_clnt *clnt = NULL;
if (!IS_ERR(clp->cl_rpcclient))
return 0;
nfs_init_timeout_values(&timeparms, proto, timeo, retrans);
clp->retrans_timeo = timeparms.to_initval;
clp->retrans_count = timeparms.to_retries;
/* create transport and client */
xprt = xprt_create_proto(proto, &clp->cl_addr, &timeparms);
if (IS_ERR(xprt)) {
dprintk("%s: cannot create RPC transport. Error = %ld\n",
__FUNCTION__, PTR_ERR(xprt));
return PTR_ERR(xprt);
}
/* Bind to a reserved port! */
xprt->resvport = 1;
/* Create the client RPC handle */
clnt = rpc_create_client(xprt, clp->cl_hostname, &nfs_program,
clp->rpc_ops->version, RPC_AUTH_UNIX);
if (IS_ERR(clnt)) {
dprintk("%s: cannot create RPC client. Error = %ld\n",
__FUNCTION__, PTR_ERR(clnt));
return PTR_ERR(clnt);
}
clnt->cl_intr = 1;
clnt->cl_softrtry = 1;
clp->cl_rpcclient = clnt;
return 0;
}