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android_kernel_motorola_sm6225/fs/nfs/nfs4state.c
Trond Myklebust 6f2e64d3e1 NFSv4: Make the NFS state model work with the nosharedcache mount option 
Consider the case where the user has mounted the remote filesystem
server:/foo on the two local directories /bar and /baz using the
nosharedcache mount option. The files /bar/file and /baz/file are
represented by different inodes in the local namespace, but refer to the
same file /foo/file on the server.
Consider the case where a process opens both /bar/file and /baz/file, then
closes /bar/file: because the nfs4_state is not shared between /bar/file
and /baz/file, the kernel will see that the nfs4_state for /bar/file is no
longer referenced, so it will send off a CLOSE rpc call. Unless the
open_owners differ, then that CLOSE call will invalidate the open state on
/baz/file too.

Conclusion: we cannot share open state owners between two different
non-shared mount instances of the same filesystem.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:48 -04:00

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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 <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/smp_lock.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/workqueue.h>
#include <linux/bitops.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "internal.h"
#define OPENOWNER_POOL_SIZE 8
const nfs4_stateid zero_stateid;
static LIST_HEAD(nfs4_clientid_list);
static int nfs4_init_client(struct nfs_client *clp, struct rpc_cred *cred)
{
int status = nfs4_proc_setclientid(clp, NFS4_CALLBACK,
nfs_callback_tcpport, cred);
if (status == 0)
status = nfs4_proc_setclientid_confirm(clp, cred);
if (status == 0)
nfs4_schedule_state_renewal(clp);
return status;
}
struct rpc_cred *nfs4_get_renew_cred(struct nfs_client *clp)
{
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct rpc_cred *cred = NULL;
for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
if (list_empty(&sp->so_states))
continue;
cred = get_rpccred(sp->so_cred);
break;
}
return cred;
}
static struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
{
struct nfs4_state_owner *sp;
struct rb_node *pos;
pos = rb_first(&clp->cl_state_owners);
if (pos != NULL) {
sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
return get_rpccred(sp->so_cred);
}
return NULL;
}
static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
__u64 minval, int maxbits)
{
struct rb_node **p, *parent;
struct nfs_unique_id *pos;
__u64 mask = ~0ULL;
if (maxbits < 64)
mask = (1ULL << maxbits) - 1ULL;
/* Ensure distribution is more or less flat */
get_random_bytes(&new->id, sizeof(new->id));
new->id &= mask;
if (new->id < minval)
new->id += minval;
retry:
p = &root->rb_node;
parent = NULL;
while (*p != NULL) {
parent = *p;
pos = rb_entry(parent, struct nfs_unique_id, rb_node);
if (new->id < pos->id)
p = &(*p)->rb_left;
else if (new->id > pos->id)
p = &(*p)->rb_right;
else
goto id_exists;
}
rb_link_node(&new->rb_node, parent, p);
rb_insert_color(&new->rb_node, root);
return;
id_exists:
for (;;) {
new->id++;
if (new->id < minval || (new->id & mask) != new->id) {
new->id = minval;
break;
}
parent = rb_next(parent);
if (parent == NULL)
break;
pos = rb_entry(parent, struct nfs_unique_id, rb_node);
if (new->id < pos->id)
break;
}
goto retry;
}
static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
{
rb_erase(&id->rb_node, root);
}
static struct nfs4_state_owner *
nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
{
struct nfs_client *clp = server->nfs_client;
struct rb_node **p = &clp->cl_state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp, *res = NULL;
while (*p != NULL) {
parent = *p;
sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
if (server < sp->so_server) {
p = &parent->rb_left;
continue;
}
if (server > sp->so_server) {
p = &parent->rb_right;
continue;
}
if (cred < sp->so_cred)
p = &parent->rb_left;
else if (cred > sp->so_cred)
p = &parent->rb_right;
else {
atomic_inc(&sp->so_count);
res = sp;
break;
}
}
return res;
}
static struct nfs4_state_owner *
nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
{
struct rb_node **p = &clp->cl_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_client_node);
if (new->so_server < sp->so_server) {
p = &parent->rb_left;
continue;
}
if (new->so_server > sp->so_server) {
p = &parent->rb_right;
continue;
}
if (new->so_cred < sp->so_cred)
p = &parent->rb_left;
else if (new->so_cred > sp->so_cred)
p = &parent->rb_right;
else {
atomic_inc(&sp->so_count);
return sp;
}
}
nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
rb_link_node(&new->so_client_node, parent, p);
rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
return new;
}
static void
nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
{
if (!RB_EMPTY_NODE(&sp->so_client_node))
rb_erase(&sp->so_client_node, &clp->cl_state_owners);
nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
}
/*
* 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(void)
{
struct nfs4_state_owner *sp;
sp = kzalloc(sizeof(*sp),GFP_KERNEL);
if (!sp)
return NULL;
spin_lock_init(&sp->so_lock);
INIT_LIST_HEAD(&sp->so_states);
INIT_LIST_HEAD(&sp->so_delegations);
rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
sp->so_seqid.sequence = &sp->so_sequence;
spin_lock_init(&sp->so_sequence.lock);
INIT_LIST_HEAD(&sp->so_sequence.list);
atomic_set(&sp->so_count, 1);
return sp;
}
void
nfs4_drop_state_owner(struct nfs4_state_owner *sp)
{
if (!RB_EMPTY_NODE(&sp->so_client_node)) {
struct nfs_client *clp = sp->so_client;
spin_lock(&clp->cl_lock);
rb_erase(&sp->so_client_node, &clp->cl_state_owners);
RB_CLEAR_NODE(&sp->so_client_node);
spin_unlock(&clp->cl_lock);
}
}
/*
* Note: must be called with clp->cl_sem held in order to prevent races
* with reboot recovery!
*/
struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *new;
spin_lock(&clp->cl_lock);
sp = nfs4_find_state_owner(server, cred);
spin_unlock(&clp->cl_lock);
if (sp != NULL)
return sp;
new = nfs4_alloc_state_owner();
if (new == NULL)
return NULL;
new->so_client = clp;
new->so_server = server;
new->so_cred = cred;
spin_lock(&clp->cl_lock);
sp = nfs4_insert_state_owner(clp, new);
spin_unlock(&clp->cl_lock);
if (sp == new)
get_rpccred(cred);
else
kfree(new);
return sp;
}
/*
* Must be called with clp->cl_sem held in order to avoid races
* with state recovery...
*/
void nfs4_put_state_owner(struct nfs4_state_owner *sp)
{
struct nfs_client *clp = sp->so_client;
struct rpc_cred *cred = sp->so_cred;
if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
return;
nfs4_remove_state_owner(clp, sp);
spin_unlock(&clp->cl_lock);
put_rpccred(cred);
kfree(sp);
}
static struct nfs4_state *
nfs4_alloc_open_state(void)
{
struct nfs4_state *state;
state = kzalloc(sizeof(*state), GFP_KERNEL);
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, mode_t mode)
{
if (state->state == mode)
return;
/* NB! List reordering - see the reclaim code for why. */
if ((mode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
if (mode & FMODE_WRITE)
list_move(&state->open_states, &state->owner->so_states);
else
list_move_tail(&state->open_states, &state->owner->so_states);
}
if (mode == 0)
list_del_init(&state->inode_states);
state->state = mode;
}
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 (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);
state->inode = igrab(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;
}
/*
* Beware! Caller must be holding exactly one
* reference to clp->cl_sem!
*/
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);
if (!list_empty(&state->inode_states))
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.
*/
void nfs4_close_state(struct path *path, struct nfs4_state *state, mode_t mode)
{
struct nfs4_state_owner *owner = state->owner;
int call_close = 0;
int newstate;
atomic_inc(&owner->so_count);
/* Protect against nfs4_find_state() */
spin_lock(&owner->so_lock);
switch (mode & (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(path, state);
}
/*
* 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)
{
struct nfs4_lock_state *pos;
list_for_each_entry(pos, &state->lock_states, ls_locks) {
if (pos->ls_owner != fl_owner)
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)
{
struct nfs4_lock_state *lsp;
struct nfs_client *clp = state->owner->so_client;
lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
if (lsp == NULL)
return NULL;
lsp->ls_seqid.sequence = &state->owner->so_sequence;
atomic_set(&lsp->ls_count, 1);
lsp->ls_owner = fl_owner;
spin_lock(&clp->cl_lock);
nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
spin_unlock(&clp->cl_lock);
INIT_LIST_HEAD(&lsp->ls_locks);
return lsp;
}
static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
{
struct nfs_client *clp = lsp->ls_state->owner->so_client;
spin_lock(&clp->cl_lock);
nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
spin_unlock(&clp->cl_lock);
kfree(lsp);
}
/*
* Return a compatible lock_state. If no initialized lock_state structure
* exists, return an uninitialized one.
*
* The caller must be holding clp->cl_sem
*/
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);
if (lsp != NULL)
break;
if (new != NULL) {
new->ls_state = state;
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(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 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);
nfs4_free_lock_state(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 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;
}
/*
* Byte-range lock aware utility to initialize the stateid of read/write
* requests.
*/
void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
{
struct nfs4_lock_state *lsp;
int seq;
do {
seq = read_seqbegin(&state->seqlock);
memcpy(dst, &state->stateid, sizeof(*dst));
} while (read_seqretry(&state->seqlock, seq));
if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
return;
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, fl_owner);
if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
spin_unlock(&state->state_lock);
nfs4_put_lock_state(lsp);
}
struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
{
struct rpc_sequence *sequence = counter->sequence;
struct nfs_seqid *new;
new = kmalloc(sizeof(*new), GFP_KERNEL);
if (new != NULL) {
new->sequence = counter;
spin_lock(&sequence->lock);
list_add_tail(&new->list, &sequence->list);
spin_unlock(&sequence->lock);
}
return new;
}
void nfs_free_seqid(struct nfs_seqid *seqid)
{
struct rpc_sequence *sequence = seqid->sequence->sequence;
spin_lock(&sequence->lock);
list_del(&seqid->list);
spin_unlock(&sequence->lock);
rpc_wake_up(&sequence->wait);
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;
printk(KERN_WARNING "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)
{
if (status == -NFS4ERR_BAD_SEQID) {
struct nfs4_state_owner *sp = container_of(seqid->sequence,
struct nfs4_state_owner, so_seqid);
nfs4_drop_state_owner(sp);
}
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 rpc_sequence *sequence = seqid->sequence->sequence;
int status = 0;
if (sequence->list.next == &seqid->list)
goto out;
spin_lock(&sequence->lock);
if (sequence->list.next != &seqid->list) {
rpc_sleep_on(&sequence->wait, task, NULL, NULL);
status = -EAGAIN;
}
spin_unlock(&sequence->lock);
out:
return status;
}
static int reclaimer(void *);
static inline void nfs4_clear_recover_bit(struct nfs_client *clp)
{
smp_mb__before_clear_bit();
clear_bit(NFS4CLNT_STATE_RECOVER, &clp->cl_state);
smp_mb__after_clear_bit();
wake_up_bit(&clp->cl_state, NFS4CLNT_STATE_RECOVER);
rpc_wake_up(&clp->cl_rpcwaitq);
}
/*
* State recovery routine
*/
static void nfs4_recover_state(struct nfs_client *clp)
{
struct task_struct *task;
__module_get(THIS_MODULE);
atomic_inc(&clp->cl_count);
task = kthread_run(reclaimer, clp, "%u.%u.%u.%u-reclaim",
NIPQUAD(clp->cl_addr.sin_addr));
if (!IS_ERR(task))
return;
nfs4_clear_recover_bit(clp);
nfs_put_client(clp);
module_put(THIS_MODULE);
}
/*
* Schedule a state recovery attempt
*/
void nfs4_schedule_state_recovery(struct nfs_client *clp)
{
if (!clp)
return;
if (test_and_set_bit(NFS4CLNT_STATE_RECOVER, &clp->cl_state) == 0)
nfs4_recover_state(clp);
}
static int nfs4_reclaim_locks(struct nfs4_state_recovery_ops *ops, struct nfs4_state *state)
{
struct inode *inode = state->inode;
struct file_lock *fl;
int status = 0;
for (fl = inode->i_flock; fl != 0; fl = fl->fl_next) {
if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
continue;
if (((struct nfs_open_context *)fl->fl_file->private_data)->state != state)
continue;
status = ops->recover_lock(state, fl);
if (status >= 0)
continue;
switch (status) {
default:
printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
__FUNCTION__, status);
case -NFS4ERR_EXPIRED:
case -NFS4ERR_NO_GRACE:
case -NFS4ERR_RECLAIM_BAD:
case -NFS4ERR_RECLAIM_CONFLICT:
/* kill_proc(fl->fl_pid, SIGLOST, 1); */
break;
case -NFS4ERR_STALE_CLIENTID:
goto out_err;
}
}
return 0;
out_err:
return status;
}
static int nfs4_reclaim_open_state(struct nfs4_state_recovery_ops *ops, struct nfs4_state_owner *sp)
{
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.
*/
list_for_each_entry(state, &sp->so_states, open_states) {
if (state->state == 0)
continue;
status = ops->recover_open(sp, state);
if (status >= 0) {
status = nfs4_reclaim_locks(ops, state);
if (status < 0)
goto out_err;
list_for_each_entry(lock, &state->lock_states, ls_locks) {
if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
printk("%s: Lock reclaim failed!\n",
__FUNCTION__);
}
continue;
}
switch (status) {
default:
printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
__FUNCTION__, status);
case -ENOENT:
case -NFS4ERR_RECLAIM_BAD:
case -NFS4ERR_RECLAIM_CONFLICT:
/*
* Open state on this file cannot be recovered
* All we can do is revert to using the zero stateid.
*/
memset(state->stateid.data, 0,
sizeof(state->stateid.data));
/* Mark the file as being 'closed' */
state->state = 0;
break;
case -NFS4ERR_EXPIRED:
case -NFS4ERR_NO_GRACE:
case -NFS4ERR_STALE_CLIENTID:
goto out_err;
}
}
return 0;
out_err:
return status;
}
static void nfs4_state_mark_reclaim(struct nfs_client *clp)
{
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;
struct nfs4_lock_state *lock;
/* Reset all sequence ids to zero */
for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
sp->so_seqid.counter = 0;
sp->so_seqid.flags = 0;
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
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);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
lock->ls_seqid.counter = 0;
lock->ls_seqid.flags = 0;
lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
}
}
spin_unlock(&sp->so_lock);
}
}
static int reclaimer(void *ptr)
{
struct nfs_client *clp = ptr;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state_recovery_ops *ops;
struct rpc_cred *cred;
int status = 0;
allow_signal(SIGKILL);
/* Ensure exclusive access to NFSv4 state */
lock_kernel();
down_write(&clp->cl_sem);
/* Are there any NFS mounts out there? */
if (list_empty(&clp->cl_superblocks))
goto out;
restart_loop:
ops = &nfs4_network_partition_recovery_ops;
/* Are there any open files on this volume? */
cred = nfs4_get_renew_cred(clp);
if (cred != NULL) {
/* Yes there are: try to renew the old lease */
status = nfs4_proc_renew(clp, cred);
switch (status) {
case 0:
case -NFS4ERR_CB_PATH_DOWN:
put_rpccred(cred);
goto out;
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_LEASE_MOVED:
ops = &nfs4_reboot_recovery_ops;
}
} else {
/* "reboot" to ensure we clear all state on the server */
clp->cl_boot_time = CURRENT_TIME;
cred = nfs4_get_setclientid_cred(clp);
}
/* We're going to have to re-establish a clientid */
nfs4_state_mark_reclaim(clp);
status = -ENOENT;
if (cred != NULL) {
status = nfs4_init_client(clp, cred);
put_rpccred(cred);
}
if (status)
goto out_error;
/* Mark all delegations for reclaim */
nfs_delegation_mark_reclaim(clp);
/* Note: list is protected by exclusive lock on cl->cl_sem */
for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
status = nfs4_reclaim_open_state(ops, sp);
if (status < 0) {
if (status == -NFS4ERR_NO_GRACE) {
ops = &nfs4_network_partition_recovery_ops;
status = nfs4_reclaim_open_state(ops, sp);
}
if (status == -NFS4ERR_STALE_CLIENTID)
goto restart_loop;
if (status == -NFS4ERR_EXPIRED)
goto restart_loop;
}
}
nfs_delegation_reap_unclaimed(clp);
out:
up_write(&clp->cl_sem);
unlock_kernel();
if (status == -NFS4ERR_CB_PATH_DOWN)
nfs_handle_cb_pathdown(clp);
nfs4_clear_recover_bit(clp);
nfs_put_client(clp);
module_put_and_exit(0);
return 0;
out_error:
printk(KERN_WARNING "Error: state recovery failed on NFSv4 server %u.%u.%u.%u with error %d\n",
NIPQUAD(clp->cl_addr.sin_addr), -status);
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
goto out;
}
/*
* Local variables:
* c-basic-offset: 8
* End:
*/
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