WSL2-Linux-Kernel/fs/nfs/nfs4state.c

989 строки
25 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/config.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/workqueue.h>
#include <linux/bitops.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#define OPENOWNER_POOL_SIZE 8
const nfs4_stateid zero_stateid;
static DEFINE_SPINLOCK(state_spinlock);
static LIST_HEAD(nfs4_clientid_list);
void
init_nfsv4_state(struct nfs_server *server)
{
server->nfs4_state = NULL;
INIT_LIST_HEAD(&server->nfs4_siblings);
}
void
destroy_nfsv4_state(struct nfs_server *server)
{
kfree(server->mnt_path);
server->mnt_path = NULL;
if (server->nfs4_state) {
nfs4_put_client(server->nfs4_state);
server->nfs4_state = NULL;
}
}
/*
* nfs4_get_client(): returns an empty client structure
* nfs4_put_client(): drops reference to client structure
*
* Since these are allocated/deallocated very rarely, we don't
* bother putting them in a slab cache...
*/
static struct nfs4_client *
nfs4_alloc_client(struct in_addr *addr)
{
struct nfs4_client *clp;
if (nfs_callback_up() < 0)
return NULL;
if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL) {
nfs_callback_down();
return NULL;
}
memcpy(&clp->cl_addr, addr, sizeof(clp->cl_addr));
init_rwsem(&clp->cl_sem);
INIT_LIST_HEAD(&clp->cl_delegations);
INIT_LIST_HEAD(&clp->cl_state_owners);
INIT_LIST_HEAD(&clp->cl_unused);
spin_lock_init(&clp->cl_lock);
atomic_set(&clp->cl_count, 1);
INIT_WORK(&clp->cl_renewd, nfs4_renew_state, clp);
INIT_LIST_HEAD(&clp->cl_superblocks);
rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS4 client");
clp->cl_rpcclient = ERR_PTR(-EINVAL);
clp->cl_boot_time = CURRENT_TIME;
clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
return clp;
}
static void
nfs4_free_client(struct nfs4_client *clp)
{
struct nfs4_state_owner *sp;
while (!list_empty(&clp->cl_unused)) {
sp = list_entry(clp->cl_unused.next,
struct nfs4_state_owner,
so_list);
list_del(&sp->so_list);
kfree(sp);
}
BUG_ON(!list_empty(&clp->cl_state_owners));
nfs_idmap_delete(clp);
if (!IS_ERR(clp->cl_rpcclient))
rpc_shutdown_client(clp->cl_rpcclient);
kfree(clp);
nfs_callback_down();
}
static struct nfs4_client *__nfs4_find_client(struct in_addr *addr)
{
struct nfs4_client *clp;
list_for_each_entry(clp, &nfs4_clientid_list, cl_servers) {
if (memcmp(&clp->cl_addr, addr, sizeof(clp->cl_addr)) == 0) {
atomic_inc(&clp->cl_count);
return clp;
}
}
return NULL;
}
struct nfs4_client *nfs4_find_client(struct in_addr *addr)
{
struct nfs4_client *clp;
spin_lock(&state_spinlock);
clp = __nfs4_find_client(addr);
spin_unlock(&state_spinlock);
return clp;
}
struct nfs4_client *
nfs4_get_client(struct in_addr *addr)
{
struct nfs4_client *clp, *new = NULL;
spin_lock(&state_spinlock);
for (;;) {
clp = __nfs4_find_client(addr);
if (clp != NULL)
break;
clp = new;
if (clp != NULL) {
list_add(&clp->cl_servers, &nfs4_clientid_list);
new = NULL;
break;
}
spin_unlock(&state_spinlock);
new = nfs4_alloc_client(addr);
spin_lock(&state_spinlock);
if (new == NULL)
break;
}
spin_unlock(&state_spinlock);
if (new)
nfs4_free_client(new);
return clp;
}
void
nfs4_put_client(struct nfs4_client *clp)
{
if (!atomic_dec_and_lock(&clp->cl_count, &state_spinlock))
return;
list_del(&clp->cl_servers);
spin_unlock(&state_spinlock);
BUG_ON(!list_empty(&clp->cl_superblocks));
rpc_wake_up(&clp->cl_rpcwaitq);
nfs4_kill_renewd(clp);
nfs4_free_client(clp);
}
static int nfs4_init_client(struct nfs4_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;
}
u32
nfs4_alloc_lockowner_id(struct nfs4_client *clp)
{
return clp->cl_lockowner_id ++;
}
static struct nfs4_state_owner *
nfs4_client_grab_unused(struct nfs4_client *clp, struct rpc_cred *cred)
{
struct nfs4_state_owner *sp = NULL;
if (!list_empty(&clp->cl_unused)) {
sp = list_entry(clp->cl_unused.next, struct nfs4_state_owner, so_list);
atomic_inc(&sp->so_count);
sp->so_cred = cred;
list_move(&sp->so_list, &clp->cl_state_owners);
clp->cl_nunused--;
}
return sp;
}
struct rpc_cred *nfs4_get_renew_cred(struct nfs4_client *clp)
{
struct nfs4_state_owner *sp;
struct rpc_cred *cred = NULL;
list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
if (list_empty(&sp->so_states))
continue;
cred = get_rpccred(sp->so_cred);
break;
}
return cred;
}
struct rpc_cred *nfs4_get_setclientid_cred(struct nfs4_client *clp)
{
struct nfs4_state_owner *sp;
if (!list_empty(&clp->cl_state_owners)) {
sp = list_entry(clp->cl_state_owners.next,
struct nfs4_state_owner, so_list);
return get_rpccred(sp->so_cred);
}
return NULL;
}
static struct nfs4_state_owner *
nfs4_find_state_owner(struct nfs4_client *clp, struct rpc_cred *cred)
{
struct nfs4_state_owner *sp, *res = NULL;
list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
if (sp->so_cred != cred)
continue;
atomic_inc(&sp->so_count);
/* Move to the head of the list */
list_move(&sp->so_list, &clp->cl_state_owners);
res = sp;
break;
}
return res;
}
/*
* 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)
{
struct nfs4_client *clp = sp->so_client;
spin_lock(&clp->cl_lock);
list_del_init(&sp->so_list);
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 nfs4_client *clp = server->nfs4_state;
struct nfs4_state_owner *sp, *new;
get_rpccred(cred);
new = nfs4_alloc_state_owner();
spin_lock(&clp->cl_lock);
sp = nfs4_find_state_owner(clp, cred);
if (sp == NULL)
sp = nfs4_client_grab_unused(clp, cred);
if (sp == NULL && new != NULL) {
list_add(&new->so_list, &clp->cl_state_owners);
new->so_client = clp;
new->so_id = nfs4_alloc_lockowner_id(clp);
new->so_cred = cred;
sp = new;
new = NULL;
}
spin_unlock(&clp->cl_lock);
kfree(new);
if (sp != NULL)
return sp;
put_rpccred(cred);
return NULL;
}
/*
* 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 nfs4_client *clp = sp->so_client;
struct rpc_cred *cred = sp->so_cred;
if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
return;
if (clp->cl_nunused >= OPENOWNER_POOL_SIZE)
goto out_free;
if (list_empty(&sp->so_list))
goto out_free;
list_move(&sp->so_list, &clp->cl_unused);
clp->cl_nunused++;
spin_unlock(&clp->cl_lock);
put_rpccred(cred);
cred = NULL;
return;
out_free:
list_del(&sp->so_list);
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);
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) {
/* Is this in the process of being freed? */
if (state->state == 0)
continue;
if (state->owner == owner) {
atomic_inc(&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 nfs4_state *state, mode_t mode)
{
struct inode *inode = state->inode;
struct nfs4_state_owner *owner = state->owner;
int oldstate, newstate = 0;
atomic_inc(&owner->so_count);
/* Protect against nfs4_find_state() */
spin_lock(&owner->so_lock);
spin_lock(&inode->i_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--;
}
oldstate = newstate = state->state;
if (state->n_rdwr == 0) {
if (state->n_rdonly == 0)
newstate &= ~FMODE_READ;
if (state->n_wronly == 0)
newstate &= ~FMODE_WRITE;
}
if (test_bit(NFS_DELEGATED_STATE, &state->flags)) {
nfs4_state_set_mode_locked(state, newstate);
oldstate = newstate;
}
spin_unlock(&inode->i_lock);
spin_unlock(&owner->so_lock);
if (oldstate != newstate && nfs4_do_close(inode, state) == 0)
return;
nfs4_put_open_state(state);
nfs4_put_state_owner(owner);
}
/*
* 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 nfs4_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);
lsp->ls_id = nfs4_alloc_lockowner_id(clp);
spin_unlock(&clp->cl_lock);
INIT_LIST_HEAD(&lsp->ls_locks);
return 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);
kfree(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);
kfree(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;
memcpy(dst, &state->stateid, sizeof(*dst));
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 inline void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
{
switch (status) {
case 0:
break;
case -NFS4ERR_BAD_SEQID:
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);
}
return 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)
{
return 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 nfs4_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 nfs4_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));
if (!IS_ERR(task))
return;
nfs4_clear_recover_bit(clp);
nfs4_put_client(clp);
module_put(THIS_MODULE);
}
/*
* Schedule a state recovery attempt
*/
void nfs4_schedule_state_recovery(struct nfs4_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 nfs4_client *clp)
{
struct nfs4_state_owner *sp;
struct nfs4_state *state;
struct nfs4_lock_state *lock;
/* Reset all sequence ids to zero */
list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
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) {
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 nfs4_client *clp = ptr;
struct nfs4_state_owner *sp;
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 */
list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
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);
nfs4_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.s_addr), -status);
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
goto out;
}
/*
* Local variables:
* c-basic-offset: 8
* End:
*/