kernel-fxtec-pro1x/fs/nfs/nfs4state.c
Trond Myklebust c8b2d0bfd3 NFSv4.1: Ensure that we free the lock stateid on the server
This ensures that the server doesn't need to keep huge numbers of
lock stateids waiting around for the final CLOSE.
See section 8.2.4 in RFC5661.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-05-06 17:24:27 -04:00

2242 lines
58 KiB
C

/*
* fs/nfs/nfs4state.c
*
* Client-side XDR for NFSv4.
*
* Copyright (c) 2002 The Regents of the University of Michigan.
* All rights reserved.
*
* Kendrick Smith <kmsmith@umich.edu>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Implementation of the NFSv4 state model. For the time being,
* this is minimal, but will be made much more complex in a
* subsequent patch.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_idmap.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/ratelimit.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>
#include <linux/sunrpc/clnt.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "internal.h"
#include "nfs4session.h"
#include "pnfs.h"
#include "netns.h"
#define NFSDBG_FACILITY NFSDBG_STATE
#define OPENOWNER_POOL_SIZE 8
const nfs4_stateid zero_stateid;
static DEFINE_MUTEX(nfs_clid_init_mutex);
int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
{
struct nfs4_setclientid_res clid = {
.clientid = clp->cl_clientid,
.confirm = clp->cl_confirm,
};
unsigned short port;
int status;
struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
goto do_confirm;
port = nn->nfs_callback_tcpport;
if (clp->cl_addr.ss_family == AF_INET6)
port = nn->nfs_callback_tcpport6;
status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
if (status != 0)
goto out;
clp->cl_clientid = clid.clientid;
clp->cl_confirm = clid.confirm;
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
do_confirm:
status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
if (status != 0)
goto out;
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
nfs4_schedule_state_renewal(clp);
out:
return status;
}
/**
* nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
*
* @clp: nfs_client under test
* @result: OUT: found nfs_client, or clp
* @cred: credential to use for trunking test
*
* Returns zero, a negative errno, or a negative NFS4ERR status.
* If zero is returned, an nfs_client pointer is planted in
* "result".
*
* Note: The returned client may not yet be marked ready.
*/
int nfs40_discover_server_trunking(struct nfs_client *clp,
struct nfs_client **result,
struct rpc_cred *cred)
{
struct nfs4_setclientid_res clid = {
.clientid = clp->cl_clientid,
.confirm = clp->cl_confirm,
};
struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
unsigned short port;
int status;
port = nn->nfs_callback_tcpport;
if (clp->cl_addr.ss_family == AF_INET6)
port = nn->nfs_callback_tcpport6;
status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
if (status != 0)
goto out;
clp->cl_clientid = clid.clientid;
clp->cl_confirm = clid.confirm;
status = nfs40_walk_client_list(clp, result, cred);
if (status == 0) {
/* Sustain the lease, even if it's empty. If the clientid4
* goes stale it's of no use for trunking discovery. */
nfs4_schedule_state_renewal(*result);
}
out:
return status;
}
struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
{
struct rpc_cred *cred = NULL;
if (clp->cl_machine_cred != NULL)
cred = get_rpccred(clp->cl_machine_cred);
return cred;
}
static struct rpc_cred *
nfs4_get_renew_cred_server_locked(struct nfs_server *server)
{
struct rpc_cred *cred = NULL;
struct nfs4_state_owner *sp;
struct rb_node *pos;
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
if (list_empty(&sp->so_states))
continue;
cred = get_rpccred(sp->so_cred);
break;
}
return cred;
}
/**
* nfs4_get_renew_cred_locked - Acquire credential for a renew operation
* @clp: client state handle
*
* Returns an rpc_cred with reference count bumped, or NULL.
* Caller must hold clp->cl_lock.
*/
struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
{
struct rpc_cred *cred = NULL;
struct nfs_server *server;
/* Use machine credentials if available */
cred = nfs4_get_machine_cred_locked(clp);
if (cred != NULL)
goto out;
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
cred = nfs4_get_renew_cred_server_locked(server);
if (cred != NULL)
break;
}
rcu_read_unlock();
out:
return cred;
}
#if defined(CONFIG_NFS_V4_1)
static int nfs41_setup_state_renewal(struct nfs_client *clp)
{
int status;
struct nfs_fsinfo fsinfo;
if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
nfs4_schedule_state_renewal(clp);
return 0;
}
status = nfs4_proc_get_lease_time(clp, &fsinfo);
if (status == 0) {
/* Update lease time and schedule renewal */
spin_lock(&clp->cl_lock);
clp->cl_lease_time = fsinfo.lease_time * HZ;
clp->cl_last_renewal = jiffies;
spin_unlock(&clp->cl_lock);
nfs4_schedule_state_renewal(clp);
}
return status;
}
/*
* Back channel returns NFS4ERR_DELAY for new requests when
* NFS4_SESSION_DRAINING is set so there is no work to be done when draining
* is ended.
*/
static void nfs4_end_drain_session(struct nfs_client *clp)
{
struct nfs4_session *ses = clp->cl_session;
struct nfs4_slot_table *tbl;
if (ses == NULL)
return;
tbl = &ses->fc_slot_table;
if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
spin_lock(&tbl->slot_tbl_lock);
nfs41_wake_slot_table(tbl);
spin_unlock(&tbl->slot_tbl_lock);
}
}
/*
* Signal state manager thread if session fore channel is drained
*/
void nfs4_session_drain_complete(struct nfs4_session *session,
struct nfs4_slot_table *tbl)
{
if (nfs4_session_draining(session))
complete(&tbl->complete);
}
static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
{
spin_lock(&tbl->slot_tbl_lock);
if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
INIT_COMPLETION(tbl->complete);
spin_unlock(&tbl->slot_tbl_lock);
return wait_for_completion_interruptible(&tbl->complete);
}
spin_unlock(&tbl->slot_tbl_lock);
return 0;
}
static int nfs4_begin_drain_session(struct nfs_client *clp)
{
struct nfs4_session *ses = clp->cl_session;
int ret = 0;
set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
/* back channel */
ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
if (ret)
return ret;
/* fore channel */
return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
}
static void nfs41_finish_session_reset(struct nfs_client *clp)
{
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
/* create_session negotiated new slot table */
clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
nfs41_setup_state_renewal(clp);
}
int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
{
int status;
if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
goto do_confirm;
nfs4_begin_drain_session(clp);
status = nfs4_proc_exchange_id(clp, cred);
if (status != 0)
goto out;
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
do_confirm:
status = nfs4_proc_create_session(clp, cred);
if (status != 0)
goto out;
nfs41_finish_session_reset(clp);
nfs_mark_client_ready(clp, NFS_CS_READY);
out:
return status;
}
/**
* nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
*
* @clp: nfs_client under test
* @result: OUT: found nfs_client, or clp
* @cred: credential to use for trunking test
*
* Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
* If NFS4_OK is returned, an nfs_client pointer is planted in
* "result".
*
* Note: The returned client may not yet be marked ready.
*/
int nfs41_discover_server_trunking(struct nfs_client *clp,
struct nfs_client **result,
struct rpc_cred *cred)
{
int status;
status = nfs4_proc_exchange_id(clp, cred);
if (status != NFS4_OK)
return status;
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
return nfs41_walk_client_list(clp, result, cred);
}
struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
{
struct rpc_cred *cred;
spin_lock(&clp->cl_lock);
cred = nfs4_get_machine_cred_locked(clp);
spin_unlock(&clp->cl_lock);
return cred;
}
#endif /* CONFIG_NFS_V4_1 */
static struct rpc_cred *
nfs4_get_setclientid_cred_server(struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
struct rpc_cred *cred = NULL;
struct nfs4_state_owner *sp;
struct rb_node *pos;
spin_lock(&clp->cl_lock);
pos = rb_first(&server->state_owners);
if (pos != NULL) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
cred = get_rpccred(sp->so_cred);
}
spin_unlock(&clp->cl_lock);
return cred;
}
/**
* nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
* @clp: client state handle
*
* Returns an rpc_cred with reference count bumped, or NULL.
*/
struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
{
struct nfs_server *server;
struct rpc_cred *cred;
spin_lock(&clp->cl_lock);
cred = nfs4_get_machine_cred_locked(clp);
spin_unlock(&clp->cl_lock);
if (cred != NULL)
goto out;
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
cred = nfs4_get_setclientid_cred_server(server);
if (cred != NULL)
break;
}
rcu_read_unlock();
out:
return cred;
}
static struct nfs4_state_owner *
nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
{
struct rb_node **p = &server->state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp;
while (*p != NULL) {
parent = *p;
sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
if (cred < sp->so_cred)
p = &parent->rb_left;
else if (cred > sp->so_cred)
p = &parent->rb_right;
else {
if (!list_empty(&sp->so_lru))
list_del_init(&sp->so_lru);
atomic_inc(&sp->so_count);
return sp;
}
}
return NULL;
}
static struct nfs4_state_owner *
nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
{
struct nfs_server *server = new->so_server;
struct rb_node **p = &server->state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp;
int err;
while (*p != NULL) {
parent = *p;
sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
if (new->so_cred < sp->so_cred)
p = &parent->rb_left;
else if (new->so_cred > sp->so_cred)
p = &parent->rb_right;
else {
if (!list_empty(&sp->so_lru))
list_del_init(&sp->so_lru);
atomic_inc(&sp->so_count);
return sp;
}
}
err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
if (err)
return ERR_PTR(err);
rb_link_node(&new->so_server_node, parent, p);
rb_insert_color(&new->so_server_node, &server->state_owners);
return new;
}
static void
nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
{
struct nfs_server *server = sp->so_server;
if (!RB_EMPTY_NODE(&sp->so_server_node))
rb_erase(&sp->so_server_node, &server->state_owners);
ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
}
static void
nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
{
sc->create_time = ktime_get();
sc->flags = 0;
sc->counter = 0;
spin_lock_init(&sc->lock);
INIT_LIST_HEAD(&sc->list);
rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
}
static void
nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
{
rpc_destroy_wait_queue(&sc->wait);
}
/*
* nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
* create a new state_owner.
*
*/
static struct nfs4_state_owner *
nfs4_alloc_state_owner(struct nfs_server *server,
struct rpc_cred *cred,
gfp_t gfp_flags)
{
struct nfs4_state_owner *sp;
sp = kzalloc(sizeof(*sp), gfp_flags);
if (!sp)
return NULL;
sp->so_server = server;
sp->so_cred = get_rpccred(cred);
spin_lock_init(&sp->so_lock);
INIT_LIST_HEAD(&sp->so_states);
nfs4_init_seqid_counter(&sp->so_seqid);
atomic_set(&sp->so_count, 1);
INIT_LIST_HEAD(&sp->so_lru);
seqcount_init(&sp->so_reclaim_seqcount);
mutex_init(&sp->so_delegreturn_mutex);
return sp;
}
static void
nfs4_drop_state_owner(struct nfs4_state_owner *sp)
{
struct rb_node *rb_node = &sp->so_server_node;
if (!RB_EMPTY_NODE(rb_node)) {
struct nfs_server *server = sp->so_server;
struct nfs_client *clp = server->nfs_client;
spin_lock(&clp->cl_lock);
if (!RB_EMPTY_NODE(rb_node)) {
rb_erase(rb_node, &server->state_owners);
RB_CLEAR_NODE(rb_node);
}
spin_unlock(&clp->cl_lock);
}
}
static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
{
nfs4_destroy_seqid_counter(&sp->so_seqid);
put_rpccred(sp->so_cred);
kfree(sp);
}
static void nfs4_gc_state_owners(struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *tmp;
unsigned long time_min, time_max;
LIST_HEAD(doomed);
spin_lock(&clp->cl_lock);
time_max = jiffies;
time_min = (long)time_max - (long)clp->cl_lease_time;
list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
/* NB: LRU is sorted so that oldest is at the head */
if (time_in_range(sp->so_expires, time_min, time_max))
break;
list_move(&sp->so_lru, &doomed);
nfs4_remove_state_owner_locked(sp);
}
spin_unlock(&clp->cl_lock);
list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
list_del(&sp->so_lru);
nfs4_free_state_owner(sp);
}
}
/**
* nfs4_get_state_owner - Look up a state owner given a credential
* @server: nfs_server to search
* @cred: RPC credential to match
*
* Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
*/
struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
struct rpc_cred *cred,
gfp_t gfp_flags)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *new;
spin_lock(&clp->cl_lock);
sp = nfs4_find_state_owner_locked(server, cred);
spin_unlock(&clp->cl_lock);
if (sp != NULL)
goto out;
new = nfs4_alloc_state_owner(server, cred, gfp_flags);
if (new == NULL)
goto out;
do {
if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
break;
spin_lock(&clp->cl_lock);
sp = nfs4_insert_state_owner_locked(new);
spin_unlock(&clp->cl_lock);
} while (sp == ERR_PTR(-EAGAIN));
if (sp != new)
nfs4_free_state_owner(new);
out:
nfs4_gc_state_owners(server);
return sp;
}
/**
* nfs4_put_state_owner - Release a nfs4_state_owner
* @sp: state owner data to release
*
* Note that we keep released state owners on an LRU
* list.
* This caches valid state owners so that they can be
* reused, to avoid the OPEN_CONFIRM on minor version 0.
* It also pins the uniquifier of dropped state owners for
* a while, to ensure that those state owner names are
* never reused.
*/
void nfs4_put_state_owner(struct nfs4_state_owner *sp)
{
struct nfs_server *server = sp->so_server;
struct nfs_client *clp = server->nfs_client;
if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
return;
sp->so_expires = jiffies;
list_add_tail(&sp->so_lru, &server->state_owners_lru);
spin_unlock(&clp->cl_lock);
}
/**
* nfs4_purge_state_owners - Release all cached state owners
* @server: nfs_server with cached state owners to release
*
* Called at umount time. Remaining state owners will be on
* the LRU with ref count of zero.
*/
void nfs4_purge_state_owners(struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *tmp;
LIST_HEAD(doomed);
spin_lock(&clp->cl_lock);
list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
list_move(&sp->so_lru, &doomed);
nfs4_remove_state_owner_locked(sp);
}
spin_unlock(&clp->cl_lock);
list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
list_del(&sp->so_lru);
nfs4_free_state_owner(sp);
}
}
static struct nfs4_state *
nfs4_alloc_open_state(void)
{
struct nfs4_state *state;
state = kzalloc(sizeof(*state), GFP_NOFS);
if (!state)
return NULL;
atomic_set(&state->count, 1);
INIT_LIST_HEAD(&state->lock_states);
spin_lock_init(&state->state_lock);
seqlock_init(&state->seqlock);
return state;
}
void
nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
{
if (state->state == fmode)
return;
/* NB! List reordering - see the reclaim code for why. */
if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
if (fmode & FMODE_WRITE)
list_move(&state->open_states, &state->owner->so_states);
else
list_move_tail(&state->open_states, &state->owner->so_states);
}
state->state = fmode;
}
static struct nfs4_state *
__nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
{
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs4_state *state;
list_for_each_entry(state, &nfsi->open_states, inode_states) {
if (state->owner != owner)
continue;
if (!nfs4_valid_open_stateid(state))
continue;
if (atomic_inc_not_zero(&state->count))
return state;
}
return NULL;
}
static void
nfs4_free_open_state(struct nfs4_state *state)
{
kfree(state);
}
struct nfs4_state *
nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
{
struct nfs4_state *state, *new;
struct nfs_inode *nfsi = NFS_I(inode);
spin_lock(&inode->i_lock);
state = __nfs4_find_state_byowner(inode, owner);
spin_unlock(&inode->i_lock);
if (state)
goto out;
new = nfs4_alloc_open_state();
spin_lock(&owner->so_lock);
spin_lock(&inode->i_lock);
state = __nfs4_find_state_byowner(inode, owner);
if (state == NULL && new != NULL) {
state = new;
state->owner = owner;
atomic_inc(&owner->so_count);
list_add(&state->inode_states, &nfsi->open_states);
ihold(inode);
state->inode = inode;
spin_unlock(&inode->i_lock);
/* Note: The reclaim code dictates that we add stateless
* and read-only stateids to the end of the list */
list_add_tail(&state->open_states, &owner->so_states);
spin_unlock(&owner->so_lock);
} else {
spin_unlock(&inode->i_lock);
spin_unlock(&owner->so_lock);
if (new)
nfs4_free_open_state(new);
}
out:
return state;
}
void nfs4_put_open_state(struct nfs4_state *state)
{
struct inode *inode = state->inode;
struct nfs4_state_owner *owner = state->owner;
if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
return;
spin_lock(&inode->i_lock);
list_del(&state->inode_states);
list_del(&state->open_states);
spin_unlock(&inode->i_lock);
spin_unlock(&owner->so_lock);
iput(inode);
nfs4_free_open_state(state);
nfs4_put_state_owner(owner);
}
/*
* Close the current file.
*/
static void __nfs4_close(struct nfs4_state *state,
fmode_t fmode, gfp_t gfp_mask, int wait)
{
struct nfs4_state_owner *owner = state->owner;
int call_close = 0;
fmode_t newstate;
atomic_inc(&owner->so_count);
/* Protect against nfs4_find_state() */
spin_lock(&owner->so_lock);
switch (fmode & (FMODE_READ | FMODE_WRITE)) {
case FMODE_READ:
state->n_rdonly--;
break;
case FMODE_WRITE:
state->n_wronly--;
break;
case FMODE_READ|FMODE_WRITE:
state->n_rdwr--;
}
newstate = FMODE_READ|FMODE_WRITE;
if (state->n_rdwr == 0) {
if (state->n_rdonly == 0) {
newstate &= ~FMODE_READ;
call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
}
if (state->n_wronly == 0) {
newstate &= ~FMODE_WRITE;
call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
}
if (newstate == 0)
clear_bit(NFS_DELEGATED_STATE, &state->flags);
}
nfs4_state_set_mode_locked(state, newstate);
spin_unlock(&owner->so_lock);
if (!call_close) {
nfs4_put_open_state(state);
nfs4_put_state_owner(owner);
} else
nfs4_do_close(state, gfp_mask, wait);
}
void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
{
__nfs4_close(state, fmode, GFP_NOFS, 0);
}
void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
{
__nfs4_close(state, fmode, GFP_KERNEL, 1);
}
/*
* Search the state->lock_states for an existing lock_owner
* that is compatible with current->files
*/
static struct nfs4_lock_state *
__nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
{
struct nfs4_lock_state *pos;
list_for_each_entry(pos, &state->lock_states, ls_locks) {
if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
continue;
switch (pos->ls_owner.lo_type) {
case NFS4_POSIX_LOCK_TYPE:
if (pos->ls_owner.lo_u.posix_owner != fl_owner)
continue;
break;
case NFS4_FLOCK_LOCK_TYPE:
if (pos->ls_owner.lo_u.flock_owner != fl_pid)
continue;
}
atomic_inc(&pos->ls_count);
return pos;
}
return NULL;
}
/*
* Return a compatible lock_state. If no initialized lock_state structure
* exists, return an uninitialized one.
*
*/
static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
{
struct nfs4_lock_state *lsp;
struct nfs_server *server = state->owner->so_server;
lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
if (lsp == NULL)
return NULL;
nfs4_init_seqid_counter(&lsp->ls_seqid);
atomic_set(&lsp->ls_count, 1);
lsp->ls_state = state;
lsp->ls_owner.lo_type = type;
switch (lsp->ls_owner.lo_type) {
case NFS4_FLOCK_LOCK_TYPE:
lsp->ls_owner.lo_u.flock_owner = fl_pid;
break;
case NFS4_POSIX_LOCK_TYPE:
lsp->ls_owner.lo_u.posix_owner = fl_owner;
break;
default:
goto out_free;
}
lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
if (lsp->ls_seqid.owner_id < 0)
goto out_free;
INIT_LIST_HEAD(&lsp->ls_locks);
return lsp;
out_free:
kfree(lsp);
return NULL;
}
void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
{
ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
nfs4_destroy_seqid_counter(&lsp->ls_seqid);
kfree(lsp);
}
/*
* Return a compatible lock_state. If no initialized lock_state structure
* exists, return an uninitialized one.
*
*/
static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
{
struct nfs4_lock_state *lsp, *new = NULL;
for(;;) {
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, owner, pid, type);
if (lsp != NULL)
break;
if (new != NULL) {
list_add(&new->ls_locks, &state->lock_states);
set_bit(LK_STATE_IN_USE, &state->flags);
lsp = new;
new = NULL;
break;
}
spin_unlock(&state->state_lock);
new = nfs4_alloc_lock_state(state, owner, pid, type);
if (new == NULL)
return NULL;
}
spin_unlock(&state->state_lock);
if (new != NULL)
nfs4_free_lock_state(state->owner->so_server, new);
return lsp;
}
/*
* Release reference to lock_state, and free it if we see that
* it is no longer in use
*/
void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
{
struct nfs_server *server;
struct nfs4_state *state;
if (lsp == NULL)
return;
state = lsp->ls_state;
if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
return;
list_del(&lsp->ls_locks);
if (list_empty(&state->lock_states))
clear_bit(LK_STATE_IN_USE, &state->flags);
spin_unlock(&state->state_lock);
server = state->owner->so_server;
if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
struct nfs_client *clp = server->nfs_client;
clp->cl_mvops->free_lock_state(server, lsp);
} else
nfs4_free_lock_state(server, lsp);
}
static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
{
struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
dst->fl_u.nfs4_fl.owner = lsp;
atomic_inc(&lsp->ls_count);
}
static void nfs4_fl_release_lock(struct file_lock *fl)
{
nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
}
static const struct file_lock_operations nfs4_fl_lock_ops = {
.fl_copy_lock = nfs4_fl_copy_lock,
.fl_release_private = nfs4_fl_release_lock,
};
int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
{
struct nfs4_lock_state *lsp;
if (fl->fl_ops != NULL)
return 0;
if (fl->fl_flags & FL_POSIX)
lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
else if (fl->fl_flags & FL_FLOCK)
lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
NFS4_FLOCK_LOCK_TYPE);
else
return -EINVAL;
if (lsp == NULL)
return -ENOMEM;
fl->fl_u.nfs4_fl.owner = lsp;
fl->fl_ops = &nfs4_fl_lock_ops;
return 0;
}
static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
struct nfs4_state *state,
const struct nfs_lockowner *lockowner)
{
struct nfs4_lock_state *lsp;
fl_owner_t fl_owner;
pid_t fl_pid;
int ret = -ENOENT;
if (lockowner == NULL)
goto out;
if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
goto out;
fl_owner = lockowner->l_owner;
fl_pid = lockowner->l_pid;
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
nfs4_stateid_copy(dst, &lsp->ls_stateid);
ret = 0;
smp_rmb();
if (!list_empty(&lsp->ls_seqid.list))
ret = -EWOULDBLOCK;
}
spin_unlock(&state->state_lock);
nfs4_put_lock_state(lsp);
out:
return ret;
}
static int nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
{
const nfs4_stateid *src;
int ret;
int seq;
do {
src = &zero_stateid;
seq = read_seqbegin(&state->seqlock);
if (test_bit(NFS_OPEN_STATE, &state->flags))
src = &state->open_stateid;
nfs4_stateid_copy(dst, src);
ret = 0;
smp_rmb();
if (!list_empty(&state->owner->so_seqid.list))
ret = -EWOULDBLOCK;
} while (read_seqretry(&state->seqlock, seq));
return ret;
}
/*
* Byte-range lock aware utility to initialize the stateid of read/write
* requests.
*/
int nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
fmode_t fmode, const struct nfs_lockowner *lockowner)
{
int ret = 0;
if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
goto out;
ret = nfs4_copy_lock_stateid(dst, state, lockowner);
if (ret != -ENOENT)
goto out;
ret = nfs4_copy_open_stateid(dst, state);
out:
if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
dst->seqid = 0;
return ret;
}
struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
{
struct nfs_seqid *new;
new = kmalloc(sizeof(*new), gfp_mask);
if (new != NULL) {
new->sequence = counter;
INIT_LIST_HEAD(&new->list);
new->task = NULL;
}
return new;
}
void nfs_release_seqid(struct nfs_seqid *seqid)
{
struct nfs_seqid_counter *sequence;
if (list_empty(&seqid->list))
return;
sequence = seqid->sequence;
spin_lock(&sequence->lock);
list_del_init(&seqid->list);
if (!list_empty(&sequence->list)) {
struct nfs_seqid *next;
next = list_first_entry(&sequence->list,
struct nfs_seqid, list);
rpc_wake_up_queued_task(&sequence->wait, next->task);
}
spin_unlock(&sequence->lock);
}
void nfs_free_seqid(struct nfs_seqid *seqid)
{
nfs_release_seqid(seqid);
kfree(seqid);
}
/*
* Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
* failed with a seqid incrementing error -
* see comments nfs_fs.h:seqid_mutating_error()
*/
static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
{
switch (status) {
case 0:
break;
case -NFS4ERR_BAD_SEQID:
if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
return;
pr_warn_ratelimited("NFS: v4 server returned a bad"
" sequence-id error on an"
" unconfirmed sequence %p!\n",
seqid->sequence);
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_STALE_STATEID:
case -NFS4ERR_BAD_STATEID:
case -NFS4ERR_BADXDR:
case -NFS4ERR_RESOURCE:
case -NFS4ERR_NOFILEHANDLE:
/* Non-seqid mutating errors */
return;
};
/*
* Note: no locking needed as we are guaranteed to be first
* on the sequence list
*/
seqid->sequence->counter++;
}
void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
{
struct nfs4_state_owner *sp = container_of(seqid->sequence,
struct nfs4_state_owner, so_seqid);
struct nfs_server *server = sp->so_server;
if (status == -NFS4ERR_BAD_SEQID)
nfs4_drop_state_owner(sp);
if (!nfs4_has_session(server->nfs_client))
nfs_increment_seqid(status, seqid);
}
/*
* Increment the seqid if the LOCK/LOCKU succeeded, or
* failed with a seqid incrementing error -
* see comments nfs_fs.h:seqid_mutating_error()
*/
void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
{
nfs_increment_seqid(status, seqid);
}
int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
{
struct nfs_seqid_counter *sequence = seqid->sequence;
int status = 0;
spin_lock(&sequence->lock);
seqid->task = task;
if (list_empty(&seqid->list))
list_add_tail(&seqid->list, &sequence->list);
if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
goto unlock;
rpc_sleep_on(&sequence->wait, task, NULL);
status = -EAGAIN;
unlock:
spin_unlock(&sequence->lock);
return status;
}
static int nfs4_run_state_manager(void *);
static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
{
smp_mb__before_clear_bit();
clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
smp_mb__after_clear_bit();
wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
rpc_wake_up(&clp->cl_rpcwaitq);
}
/*
* Schedule the nfs_client asynchronous state management routine
*/
void nfs4_schedule_state_manager(struct nfs_client *clp)
{
struct task_struct *task;
char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
return;
__module_get(THIS_MODULE);
atomic_inc(&clp->cl_count);
/* The rcu_read_lock() is not strictly necessary, as the state
* manager is the only thread that ever changes the rpc_xprt
* after it's initialized. At this point, we're single threaded. */
rcu_read_lock();
snprintf(buf, sizeof(buf), "%s-manager",
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
rcu_read_unlock();
task = kthread_run(nfs4_run_state_manager, clp, buf);
if (IS_ERR(task)) {
printk(KERN_ERR "%s: kthread_run: %ld\n",
__func__, PTR_ERR(task));
nfs4_clear_state_manager_bit(clp);
nfs_put_client(clp);
module_put(THIS_MODULE);
}
}
/*
* Schedule a lease recovery attempt
*/
void nfs4_schedule_lease_recovery(struct nfs_client *clp)
{
if (!clp)
return;
if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
dprintk("%s: scheduling lease recovery for server %s\n", __func__,
clp->cl_hostname);
nfs4_schedule_state_manager(clp);
}
EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
int nfs4_wait_clnt_recover(struct nfs_client *clp)
{
int res;
might_sleep();
res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
nfs_wait_bit_killable, TASK_KILLABLE);
if (res)
return res;
if (clp->cl_cons_state < 0)
return clp->cl_cons_state;
return 0;
}
int nfs4_client_recover_expired_lease(struct nfs_client *clp)
{
unsigned int loop;
int ret;
for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
ret = nfs4_wait_clnt_recover(clp);
if (ret != 0)
break;
if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
!test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
break;
nfs4_schedule_state_manager(clp);
ret = -EIO;
}
return ret;
}
/*
* nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
* @clp: client to process
*
* Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
* resend of the SETCLIENTID and hence re-establish the
* callback channel. Then return all existing delegations.
*/
static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
{
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs_expire_all_delegations(clp);
dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
clp->cl_hostname);
}
void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
{
nfs40_handle_cb_pathdown(clp);
nfs4_schedule_state_manager(clp);
}
static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
{
set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
/* Don't recover state that expired before the reboot */
if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
return 0;
}
set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
return 1;
}
static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
{
set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
return 1;
}
int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
{
struct nfs_client *clp = server->nfs_client;
if (!nfs4_valid_open_stateid(state))
return -EBADF;
nfs4_state_mark_reclaim_nograce(clp, state);
dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
clp->cl_hostname);
nfs4_schedule_state_manager(clp);
return 0;
}
EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
void nfs_inode_find_state_and_recover(struct inode *inode,
const nfs4_stateid *stateid)
{
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_context *ctx;
struct nfs4_state *state;
bool found = false;
spin_lock(&inode->i_lock);
list_for_each_entry(ctx, &nfsi->open_files, list) {
state = ctx->state;
if (state == NULL)
continue;
if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
continue;
if (!nfs4_stateid_match(&state->stateid, stateid))
continue;
nfs4_state_mark_reclaim_nograce(clp, state);
found = true;
}
spin_unlock(&inode->i_lock);
if (found)
nfs4_schedule_state_manager(clp);
}
static void nfs4_state_mark_open_context_bad(struct nfs4_state *state)
{
struct inode *inode = state->inode;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_context *ctx;
spin_lock(&inode->i_lock);
list_for_each_entry(ctx, &nfsi->open_files, list) {
if (ctx->state != state)
continue;
set_bit(NFS_CONTEXT_BAD, &ctx->flags);
}
spin_unlock(&inode->i_lock);
}
static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
{
set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
nfs4_state_mark_open_context_bad(state);
}
static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
{
struct inode *inode = state->inode;
struct nfs_inode *nfsi = NFS_I(inode);
struct file_lock *fl;
int status = 0;
if (inode->i_flock == NULL)
return 0;
/* Guard against delegation returns and new lock/unlock calls */
down_write(&nfsi->rwsem);
/* Protect inode->i_flock using the BKL */
lock_flocks();
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
continue;
if (nfs_file_open_context(fl->fl_file)->state != state)
continue;
unlock_flocks();
status = ops->recover_lock(state, fl);
switch (status) {
case 0:
break;
case -ESTALE:
case -NFS4ERR_ADMIN_REVOKED:
case -NFS4ERR_STALE_STATEID:
case -NFS4ERR_BAD_STATEID:
case -NFS4ERR_EXPIRED:
case -NFS4ERR_NO_GRACE:
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
goto out;
default:
printk(KERN_ERR "NFS: %s: unhandled error %d. "
"Zeroing state\n", __func__, status);
case -ENOMEM:
case -NFS4ERR_DENIED:
case -NFS4ERR_RECLAIM_BAD:
case -NFS4ERR_RECLAIM_CONFLICT:
/* kill_proc(fl->fl_pid, SIGLOST, 1); */
status = 0;
}
lock_flocks();
}
unlock_flocks();
out:
up_write(&nfsi->rwsem);
return status;
}
static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
{
struct nfs4_state *state;
struct nfs4_lock_state *lock;
int status = 0;
/* Note: we rely on the sp->so_states list being ordered
* so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
* states first.
* This is needed to ensure that the server won't give us any
* read delegations that we have to return if, say, we are
* recovering after a network partition or a reboot from a
* server that doesn't support a grace period.
*/
spin_lock(&sp->so_lock);
write_seqcount_begin(&sp->so_reclaim_seqcount);
restart:
list_for_each_entry(state, &sp->so_states, open_states) {
if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
continue;
if (!nfs4_valid_open_stateid(state))
continue;
if (state->state == 0)
continue;
atomic_inc(&state->count);
spin_unlock(&sp->so_lock);
status = ops->recover_open(sp, state);
if (status >= 0) {
status = nfs4_reclaim_locks(state, ops);
if (status >= 0) {
spin_lock(&state->state_lock);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
pr_warn_ratelimited("NFS: "
"%s: Lock reclaim "
"failed!\n", __func__);
}
spin_unlock(&state->state_lock);
nfs4_put_open_state(state);
spin_lock(&sp->so_lock);
goto restart;
}
}
switch (status) {
default:
printk(KERN_ERR "NFS: %s: unhandled error %d. "
"Zeroing state\n", __func__, status);
case -ENOENT:
case -ENOMEM:
case -ESTALE:
/*
* Open state on this file cannot be recovered
* All we can do is revert to using the zero stateid.
*/
nfs4_state_mark_recovery_failed(state, status);
break;
case -EAGAIN:
ssleep(1);
case -NFS4ERR_ADMIN_REVOKED:
case -NFS4ERR_STALE_STATEID:
case -NFS4ERR_BAD_STATEID:
case -NFS4ERR_RECLAIM_BAD:
case -NFS4ERR_RECLAIM_CONFLICT:
nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
break;
case -NFS4ERR_EXPIRED:
case -NFS4ERR_NO_GRACE:
nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
goto out_err;
}
nfs4_put_open_state(state);
spin_lock(&sp->so_lock);
goto restart;
}
write_seqcount_end(&sp->so_reclaim_seqcount);
spin_unlock(&sp->so_lock);
return 0;
out_err:
nfs4_put_open_state(state);
spin_lock(&sp->so_lock);
write_seqcount_end(&sp->so_reclaim_seqcount);
spin_unlock(&sp->so_lock);
return status;
}
static void nfs4_clear_open_state(struct nfs4_state *state)
{
struct nfs4_lock_state *lock;
clear_bit(NFS_DELEGATED_STATE, &state->flags);
clear_bit(NFS_O_RDONLY_STATE, &state->flags);
clear_bit(NFS_O_WRONLY_STATE, &state->flags);
clear_bit(NFS_O_RDWR_STATE, &state->flags);
spin_lock(&state->state_lock);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
lock->ls_seqid.flags = 0;
clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
}
spin_unlock(&state->state_lock);
}
static void nfs4_reset_seqids(struct nfs_server *server,
int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;
spin_lock(&clp->cl_lock);
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
sp->so_seqid.flags = 0;
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
if (mark_reclaim(clp, state))
nfs4_clear_open_state(state);
}
spin_unlock(&sp->so_lock);
}
spin_unlock(&clp->cl_lock);
}
static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
{
struct nfs_server *server;
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
nfs4_reset_seqids(server, mark_reclaim);
rcu_read_unlock();
}
static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
{
/* Mark all delegations for reclaim */
nfs_delegation_mark_reclaim(clp);
nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
}
static void nfs4_reclaim_complete(struct nfs_client *clp,
const struct nfs4_state_recovery_ops *ops)
{
/* Notify the server we're done reclaiming our state */
if (ops->reclaim_complete)
(void)ops->reclaim_complete(clp);
}
static void nfs4_clear_reclaim_server(struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;
spin_lock(&clp->cl_lock);
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
&state->flags))
continue;
nfs4_state_mark_reclaim_nograce(clp, state);
}
spin_unlock(&sp->so_lock);
}
spin_unlock(&clp->cl_lock);
}
static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
{
struct nfs_server *server;
if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
return 0;
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
nfs4_clear_reclaim_server(server);
rcu_read_unlock();
nfs_delegation_reap_unclaimed(clp);
return 1;
}
static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
{
if (!nfs4_state_clear_reclaim_reboot(clp))
return;
nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
}
static void nfs_delegation_clear_all(struct nfs_client *clp)
{
nfs_delegation_mark_reclaim(clp);
nfs_delegation_reap_unclaimed(clp);
}
static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
{
nfs_delegation_clear_all(clp);
nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
}
static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
{
switch (error) {
case 0:
break;
case -NFS4ERR_CB_PATH_DOWN:
nfs40_handle_cb_pathdown(clp);
break;
case -NFS4ERR_NO_GRACE:
nfs4_state_end_reclaim_reboot(clp);
break;
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_LEASE_MOVED:
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_clear_reclaim_reboot(clp);
nfs4_state_start_reclaim_reboot(clp);
break;
case -NFS4ERR_EXPIRED:
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_start_reclaim_nograce(clp);
break;
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_DEADSESSION:
case -NFS4ERR_SEQ_FALSE_RETRY:
case -NFS4ERR_SEQ_MISORDERED:
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
/* Zero session reset errors */
break;
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
break;
default:
dprintk("%s: failed to handle error %d for server %s\n",
__func__, error, clp->cl_hostname);
return error;
}
dprintk("%s: handled error %d for server %s\n", __func__, error,
clp->cl_hostname);
return 0;
}
static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
{
struct nfs4_state_owner *sp;
struct nfs_server *server;
struct rb_node *pos;
int status = 0;
restart:
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
nfs4_purge_state_owners(server);
spin_lock(&clp->cl_lock);
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos,
struct nfs4_state_owner, so_server_node);
if (!test_and_clear_bit(ops->owner_flag_bit,
&sp->so_flags))
continue;
atomic_inc(&sp->so_count);
spin_unlock(&clp->cl_lock);
rcu_read_unlock();
status = nfs4_reclaim_open_state(sp, ops);
if (status < 0) {
set_bit(ops->owner_flag_bit, &sp->so_flags);
nfs4_put_state_owner(sp);
return nfs4_recovery_handle_error(clp, status);
}
nfs4_put_state_owner(sp);
goto restart;
}
spin_unlock(&clp->cl_lock);
}
rcu_read_unlock();
return status;
}
static int nfs4_check_lease(struct nfs_client *clp)
{
struct rpc_cred *cred;
const struct nfs4_state_maintenance_ops *ops =
clp->cl_mvops->state_renewal_ops;
int status;
/* Is the client already known to have an expired lease? */
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
return 0;
spin_lock(&clp->cl_lock);
cred = ops->get_state_renewal_cred_locked(clp);
spin_unlock(&clp->cl_lock);
if (cred == NULL) {
cred = nfs4_get_setclientid_cred(clp);
status = -ENOKEY;
if (cred == NULL)
goto out;
}
status = ops->renew_lease(clp, cred);
put_rpccred(cred);
if (status == -ETIMEDOUT) {
set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
return 0;
}
out:
return nfs4_recovery_handle_error(clp, status);
}
/* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
* and for recoverable errors on EXCHANGE_ID for v4.1
*/
static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
{
switch (status) {
case -NFS4ERR_SEQ_MISORDERED:
if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
return -ESERVERFAULT;
/* Lease confirmation error: retry after purging the lease */
ssleep(1);
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
break;
case -NFS4ERR_STALE_CLIENTID:
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
nfs4_state_clear_reclaim_reboot(clp);
nfs4_state_start_reclaim_reboot(clp);
break;
case -NFS4ERR_CLID_INUSE:
pr_err("NFS: Server %s reports our clientid is in use\n",
clp->cl_hostname);
nfs_mark_client_ready(clp, -EPERM);
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
return -EPERM;
case -EACCES:
case -NFS4ERR_DELAY:
case -ETIMEDOUT:
case -EAGAIN:
ssleep(1);
break;
case -NFS4ERR_MINOR_VERS_MISMATCH:
if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
dprintk("%s: exit with error %d for server %s\n",
__func__, -EPROTONOSUPPORT, clp->cl_hostname);
return -EPROTONOSUPPORT;
case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
* in nfs4_exchange_id */
default:
dprintk("%s: exit with error %d for server %s\n", __func__,
status, clp->cl_hostname);
return status;
}
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
dprintk("%s: handled error %d for server %s\n", __func__, status,
clp->cl_hostname);
return 0;
}
static int nfs4_establish_lease(struct nfs_client *clp)
{
struct rpc_cred *cred;
const struct nfs4_state_recovery_ops *ops =
clp->cl_mvops->reboot_recovery_ops;
int status;
cred = ops->get_clid_cred(clp);
if (cred == NULL)
return -ENOENT;
status = ops->establish_clid(clp, cred);
put_rpccred(cred);
if (status != 0)
return status;
pnfs_destroy_all_layouts(clp);
return 0;
}
/*
* Returns zero or a negative errno. NFS4ERR values are converted
* to local errno values.
*/
static int nfs4_reclaim_lease(struct nfs_client *clp)
{
int status;
status = nfs4_establish_lease(clp);
if (status < 0)
return nfs4_handle_reclaim_lease_error(clp, status);
if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
nfs4_state_start_reclaim_nograce(clp);
if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
return 0;
}
static int nfs4_purge_lease(struct nfs_client *clp)
{
int status;
status = nfs4_establish_lease(clp);
if (status < 0)
return nfs4_handle_reclaim_lease_error(clp, status);
clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_start_reclaim_nograce(clp);
return 0;
}
/**
* nfs4_discover_server_trunking - Detect server IP address trunking
*
* @clp: nfs_client under test
* @result: OUT: found nfs_client, or clp
*
* Returns zero or a negative errno. If zero is returned,
* an nfs_client pointer is planted in "result".
*
* Note: since we are invoked in process context, and
* not from inside the state manager, we cannot use
* nfs4_handle_reclaim_lease_error().
*/
int nfs4_discover_server_trunking(struct nfs_client *clp,
struct nfs_client **result)
{
const struct nfs4_state_recovery_ops *ops =
clp->cl_mvops->reboot_recovery_ops;
struct rpc_clnt *clnt;
struct rpc_cred *cred;
int i, status;
dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
clnt = clp->cl_rpcclient;
i = 0;
mutex_lock(&nfs_clid_init_mutex);
again:
status = -ENOENT;
cred = ops->get_clid_cred(clp);
if (cred == NULL)
goto out_unlock;
status = ops->detect_trunking(clp, result, cred);
put_rpccred(cred);
switch (status) {
case 0:
break;
case -NFS4ERR_DELAY:
case -ETIMEDOUT:
case -EAGAIN:
ssleep(1);
case -NFS4ERR_STALE_CLIENTID:
dprintk("NFS: %s after status %d, retrying\n",
__func__, status);
goto again;
case -EACCES:
if (i++)
break;
case -NFS4ERR_CLID_INUSE:
case -NFS4ERR_WRONGSEC:
clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
if (IS_ERR(clnt)) {
status = PTR_ERR(clnt);
break;
}
/* Note: this is safe because we haven't yet marked the
* client as ready, so we are the only user of
* clp->cl_rpcclient
*/
clnt = xchg(&clp->cl_rpcclient, clnt);
rpc_shutdown_client(clnt);
clnt = clp->cl_rpcclient;
goto again;
case -NFS4ERR_MINOR_VERS_MISMATCH:
status = -EPROTONOSUPPORT;
break;
case -EKEYEXPIRED:
case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
* in nfs4_exchange_id */
status = -EKEYEXPIRED;
break;
default:
pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
__func__, status);
status = -EIO;
}
out_unlock:
mutex_unlock(&nfs_clid_init_mutex);
dprintk("NFS: %s: status = %d\n", __func__, status);
return status;
}
#ifdef CONFIG_NFS_V4_1
void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
{
struct nfs_client *clp = session->clp;
switch (err) {
default:
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
break;
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
}
nfs4_schedule_lease_recovery(clp);
}
EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
static void nfs41_ping_server(struct nfs_client *clp)
{
/* Use CHECK_LEASE to ping the server with a SEQUENCE */
set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
nfs4_schedule_state_manager(clp);
}
void nfs41_server_notify_target_slotid_update(struct nfs_client *clp)
{
nfs41_ping_server(clp);
}
void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp)
{
nfs41_ping_server(clp);
}
static void nfs4_reset_all_state(struct nfs_client *clp)
{
if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
nfs4_state_start_reclaim_nograce(clp);
dprintk("%s: scheduling reset of all state for server %s!\n",
__func__, clp->cl_hostname);
nfs4_schedule_state_manager(clp);
}
}
static void nfs41_handle_server_reboot(struct nfs_client *clp)
{
if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
nfs4_state_start_reclaim_reboot(clp);
dprintk("%s: server %s rebooted!\n", __func__,
clp->cl_hostname);
nfs4_schedule_state_manager(clp);
}
}
static void nfs41_handle_state_revoked(struct nfs_client *clp)
{
nfs4_reset_all_state(clp);
dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
}
static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
{
/* This will need to handle layouts too */
nfs_expire_all_delegations(clp);
dprintk("%s: Recallable state revoked on server %s!\n", __func__,
clp->cl_hostname);
}
static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
{
nfs_expire_all_delegations(clp);
if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
nfs4_schedule_state_manager(clp);
dprintk("%s: server %s declared a backchannel fault\n", __func__,
clp->cl_hostname);
}
static void nfs41_handle_cb_path_down(struct nfs_client *clp)
{
if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
&clp->cl_state) == 0)
nfs4_schedule_state_manager(clp);
}
void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
{
if (!flags)
return;
dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
__func__, clp->cl_hostname, clp->cl_clientid, flags);
if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
nfs41_handle_server_reboot(clp);
if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
SEQ4_STATUS_ADMIN_STATE_REVOKED |
SEQ4_STATUS_LEASE_MOVED))
nfs41_handle_state_revoked(clp);
if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
nfs41_handle_recallable_state_revoked(clp);
if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
nfs41_handle_backchannel_fault(clp);
else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
SEQ4_STATUS_CB_PATH_DOWN_SESSION))
nfs41_handle_cb_path_down(clp);
}
static int nfs4_reset_session(struct nfs_client *clp)
{
struct rpc_cred *cred;
int status;
if (!nfs4_has_session(clp))
return 0;
nfs4_begin_drain_session(clp);
cred = nfs4_get_exchange_id_cred(clp);
status = nfs4_proc_destroy_session(clp->cl_session, cred);
switch (status) {
case 0:
case -NFS4ERR_BADSESSION:
case -NFS4ERR_DEADSESSION:
break;
case -NFS4ERR_BACK_CHAN_BUSY:
case -NFS4ERR_DELAY:
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
status = 0;
ssleep(1);
goto out;
default:
status = nfs4_recovery_handle_error(clp, status);
goto out;
}
memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
status = nfs4_proc_create_session(clp, cred);
if (status) {
dprintk("%s: session reset failed with status %d for server %s!\n",
__func__, status, clp->cl_hostname);
status = nfs4_handle_reclaim_lease_error(clp, status);
goto out;
}
nfs41_finish_session_reset(clp);
dprintk("%s: session reset was successful for server %s!\n",
__func__, clp->cl_hostname);
out:
if (cred)
put_rpccred(cred);
return status;
}
static int nfs4_bind_conn_to_session(struct nfs_client *clp)
{
struct rpc_cred *cred;
int ret;
if (!nfs4_has_session(clp))
return 0;
nfs4_begin_drain_session(clp);
cred = nfs4_get_exchange_id_cred(clp);
ret = nfs4_proc_bind_conn_to_session(clp, cred);
if (cred)
put_rpccred(cred);
clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
switch (ret) {
case 0:
dprintk("%s: bind_conn_to_session was successful for server %s!\n",
__func__, clp->cl_hostname);
break;
case -NFS4ERR_DELAY:
ssleep(1);
set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
break;
default:
return nfs4_recovery_handle_error(clp, ret);
}
return 0;
}
#else /* CONFIG_NFS_V4_1 */
static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
static int nfs4_bind_conn_to_session(struct nfs_client *clp)
{
return 0;
}
#endif /* CONFIG_NFS_V4_1 */
static void nfs4_state_manager(struct nfs_client *clp)
{
int status = 0;
const char *section = "", *section_sep = "";
/* Ensure exclusive access to NFSv4 state */
do {
if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
section = "purge state";
status = nfs4_purge_lease(clp);
if (status < 0)
goto out_error;
continue;
}
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
section = "lease expired";
/* We're going to have to re-establish a clientid */
status = nfs4_reclaim_lease(clp);
if (status < 0)
goto out_error;
continue;
}
/* Initialize or reset the session */
if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
section = "reset session";
status = nfs4_reset_session(clp);
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
continue;
if (status < 0)
goto out_error;
}
/* Send BIND_CONN_TO_SESSION */
if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
&clp->cl_state)) {
section = "bind conn to session";
status = nfs4_bind_conn_to_session(clp);
if (status < 0)
goto out_error;
continue;
}
if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
section = "check lease";
status = nfs4_check_lease(clp);
if (status < 0)
goto out_error;
continue;
}
/* First recover reboot state... */
if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
section = "reclaim reboot";
status = nfs4_do_reclaim(clp,
clp->cl_mvops->reboot_recovery_ops);
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
continue;
nfs4_state_end_reclaim_reboot(clp);
if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
continue;
if (status < 0)
goto out_error;
}
/* Now recover expired state... */
if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
section = "reclaim nograce";
status = nfs4_do_reclaim(clp,
clp->cl_mvops->nograce_recovery_ops);
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
continue;
if (status < 0)
goto out_error;
}
nfs4_end_drain_session(clp);
if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
nfs_client_return_marked_delegations(clp);
continue;
}
nfs4_clear_state_manager_bit(clp);
/* Did we race with an attempt to give us more work? */
if (clp->cl_state == 0)
break;
if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
break;
} while (atomic_read(&clp->cl_count) > 1);
return;
out_error:
if (strlen(section))
section_sep = ": ";
pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
" with error %d\n", section_sep, section,
clp->cl_hostname, -status);
ssleep(1);
nfs4_end_drain_session(clp);
nfs4_clear_state_manager_bit(clp);
}
static int nfs4_run_state_manager(void *ptr)
{
struct nfs_client *clp = ptr;
allow_signal(SIGKILL);
nfs4_state_manager(clp);
nfs_put_client(clp);
module_put_and_exit(0);
return 0;
}
/*
* Local variables:
* c-basic-offset: 8
* End:
*/