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nfs4state.c
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/*
* fs/nfs/nfs4state.c
*
* Client-side XDR for NFSv4.
*
* Copyright (c) 2002 The Regents of the University of Michigan.
* All rights reserved.
*
* Kendrick Smith <[email protected]>
*
* 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/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 "nfs4idmap.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 = {
{ .data = { 0 } },
.type = NFS4_SPECIAL_STATEID_TYPE,
};
const nfs4_stateid invalid_stateid = {
{
/* Funky initialiser keeps older gcc versions happy */
.data = { 0xff, 0xff, 0xff, 0xff, 0 },
},
.type = NFS4_INVALID_STATEID_TYPE,
};
const nfs4_stateid current_stateid = {
{
/* Funky initialiser keeps older gcc versions happy */
.data = { 0x0, 0x0, 0x0, 0x1, 0 },
},
.type = NFS4_SPECIAL_STATEID_TYPE,
};
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 void nfs4_root_machine_cred(struct nfs_client *clp)
{
struct rpc_cred *cred, *new;
new = rpc_lookup_machine_cred(NULL);
spin_lock(&clp->cl_lock);
cred = clp->cl_machine_cred;
clp->cl_machine_cred = new;
spin_unlock(&clp->cl_lock);
if (cred != NULL)
put_rpccred(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;
}
static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
{
if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
spin_lock(&tbl->slot_tbl_lock);
nfs41_wake_slot_table(tbl);
spin_unlock(&tbl->slot_tbl_lock);
}
}
static void nfs4_end_drain_session(struct nfs_client *clp)
{
struct nfs4_session *ses = clp->cl_session;
if (clp->cl_slot_tbl) {
nfs4_end_drain_slot_table(clp->cl_slot_tbl);
return;
}
if (ses != NULL) {
nfs4_end_drain_slot_table(&ses->bc_slot_table);
nfs4_end_drain_slot_table(&ses->fc_slot_table);
}
}
static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
{
set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
spin_lock(&tbl->slot_tbl_lock);
if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
reinit_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;
if (clp->cl_slot_tbl)
return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
/* back channel */
ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
if (ret)
return ret;
/* fore channel */
return nfs4_drain_slot_tbl(&ses->fc_slot_table);
}
#if defined(CONFIG_NFS_V4_1)
static int nfs41_setup_state_renewal(struct nfs_client *clp)
{
int status;
struct nfs_fsinfo fsinfo;
unsigned long now;
if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
nfs4_schedule_state_renewal(clp);
return 0;
}
now = jiffies;
status = nfs4_proc_get_lease_time(clp, &fsinfo);
if (status == 0) {
nfs4_set_lease_period(clp, fsinfo.lease_time * HZ, now);
nfs4_schedule_state_renewal(clp);
}
return status;
}
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;
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;
status = nfs41_walk_client_list(clp, result, cred);
if (status < 0)
return status;
if (clp != *result)
return 0;
/*
* Purge state if the client id was established in a prior
* instance and the client id could not have arrived on the
* server via Transparent State Migration.
*/
if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) {
if (!test_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags))
set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
else
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
}
nfs4_schedule_state_manager(clp);
status = nfs_wait_client_init_complete(clp);
if (status < 0)
nfs_put_client(clp);
return status;
}
#endif /* CONFIG_NFS_V4_1 */
/**
* nfs4_get_clid_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_clid_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;
}
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;
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;
}
}
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);
}
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_seqid.owner_id = ida_simple_get(&server->openowner_id, 0, 0,
gfp_flags);
if (sp->so_seqid.owner_id < 0) {
kfree(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_reset_state_owner(struct nfs4_state_owner *sp)
{
/* This state_owner is no longer usable, but must
* remain in place so that state recovery can find it
* and the opens associated with it.
* It may also be used for new 'open' request to
* return a delegation to the server.
* So update the 'create_time' so that it looks like
* a new state_owner. This will cause the server to
* request an OPEN_CONFIRM to start a new sequence.
*/
sp->so_seqid.create_time = ktime_get();
}
static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
{
nfs4_destroy_seqid_counter(&sp->so_seqid);
put_rpccred(sp->so_cred);
ida_simple_remove(&sp->so_server->openowner_id, sp->so_seqid.owner_id);
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;
spin_lock(&clp->cl_lock);
sp = nfs4_insert_state_owner_locked(new);
spin_unlock(&clp->cl_lock);
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;
refcount_set(&state->count, 1);
INIT_LIST_HEAD(&state->lock_states);
spin_lock_init(&state->state_lock);
seqlock_init(&state->seqlock);
init_waitqueue_head(&state->waitq);
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_rcu(state, &nfsi->open_states, inode_states) {
if (state->owner != owner)
continue;
if (!nfs4_valid_open_stateid(state))
continue;
if (refcount_inc_not_zero(&state->count))
return state;
}
return NULL;
}
static void
nfs4_free_open_state(struct nfs4_state *state)
{
kfree_rcu(state, rcu_head);
}
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);
rcu_read_lock();
state = __nfs4_find_state_byowner(inode, owner);
rcu_read_unlock();
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_rcu(&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 (!refcount_dec_and_lock(&state->count, &owner->so_lock))
return;
spin_lock(&inode->i_lock);
list_del_rcu(&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 either of the given owners.
* If the second is non-zero, then the first refers to a Posix-lock
* owner (current->files) and the second refers to a flock/OFD
* owner (struct file*). In that case, prefer a match for the first
* owner.
* If both sorts of locks are held on the one file we cannot know
* which stateid was intended to be used, so a "correct" choice cannot
* be made. Failing that, a "consistent" choice is preferable. The
* consistent choice we make is to prefer the first owner, that of a
* Posix lock.
*/
static struct nfs4_lock_state *
__nfs4_find_lock_state(struct nfs4_state *state,
fl_owner_t fl_owner, fl_owner_t fl_owner2)
{
struct nfs4_lock_state *pos, *ret = NULL;
list_for_each_entry(pos, &state->lock_states, ls_locks) {
if (pos->ls_owner == fl_owner) {
ret = pos;
break;
}
if (pos->ls_owner == fl_owner2)
ret = pos;
}
if (ret)
refcount_inc(&ret->ls_count);
return ret;
}
/*
* 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)
{
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);
refcount_set(&lsp->ls_count, 1);
lsp->ls_state = state;
lsp->ls_owner = fl_owner;
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)
{
struct nfs4_lock_state *lsp, *new = NULL;
for(;;) {
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, owner, NULL);
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);
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 (!refcount_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;
refcount_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;
lsp = nfs4_get_lock_state(state, fl->fl_owner);
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_lock_context *l_ctx)
{
struct nfs4_lock_state *lsp;
fl_owner_t fl_owner, fl_flock_owner;
int ret = -ENOENT;
if (l_ctx == NULL)
goto out;
if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
goto out;
fl_owner = l_ctx->lockowner;
fl_flock_owner = l_ctx->open_context->flock_owner;
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, fl_owner, fl_flock_owner);
if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
ret = -EIO;
else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
nfs4_stateid_copy(dst, &lsp->ls_stateid);
ret = 0;
}
spin_unlock(&state->state_lock);
nfs4_put_lock_state(lsp);
out:
return ret;