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[PATCH] NFSv4: Clean up nfs4 lock state accounting 

Ensure that lock owner structures are not released prematurely.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2005-06-22 17:16:32 +00:00
parent ecdbf769b2
commit 8d0a8a9d0e
5 changed files with 126 additions and 152 deletions
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9
fs/nfs/nfs4_fs.h
View File

@ -128,6 +128,7 @@ struct nfs4_state_owner {
struct nfs4_lock_state {
struct list_head ls_locks; /* Other lock stateids */
struct nfs4_state * ls_state; /* Pointer to open state */
fl_owner_t ls_owner; /* POSIX lock owner */
#define NFS_LOCK_INITIALIZED 1
int ls_flags;
@ -153,7 +154,7 @@ struct nfs4_state {
unsigned long flags; /* Do we hold any locks? */
struct semaphore lock_sema; /* Serializes file locking operations */
rwlock_t state_lock; /* Protects the lock_states list */
spinlock_t state_lock; /* Protects the lock_states list */
nfs4_stateid stateid;
@ -225,12 +226,8 @@ extern void nfs4_close_state(struct nfs4_state *, mode_t);
extern struct nfs4_state *nfs4_find_state(struct inode *, struct rpc_cred *, mode_t mode);
extern void nfs4_increment_seqid(int status, struct nfs4_state_owner *sp);
extern void nfs4_schedule_state_recovery(struct nfs4_client *);
extern struct nfs4_lock_state *nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t);
extern struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t);
extern void nfs4_put_lock_state(struct nfs4_lock_state *state);
extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
extern void nfs4_increment_lock_seqid(int status, struct nfs4_lock_state *ls);
extern void nfs4_notify_setlk(struct nfs4_state *, struct file_lock *, struct nfs4_lock_state *);
extern void nfs4_notify_unlck(struct nfs4_state *, struct file_lock *, struct nfs4_lock_state *);
extern void nfs4_copy_stateid(nfs4_stateid *, struct nfs4_state *, fl_owner_t);
extern const nfs4_stateid zero_stateid;

69
fs/nfs/nfs4proc.c
View File

@ -2626,14 +2626,11 @@ static int _nfs4_proc_getlk(struct nfs4_state *state, int cmd, struct file_lock
down_read(&clp->cl_sem);
nlo.clientid = clp->cl_clientid;
down(&state->lock_sema);
lsp = nfs4_find_lock_state(state, request->fl_owner);
if (lsp)
nlo.id = lsp->ls_id;
else {
spin_lock(&clp->cl_lock);
nlo.id = nfs4_alloc_lockowner_id(clp);
spin_unlock(&clp->cl_lock);
}
status = nfs4_set_lock_state(state, request);
if (status != 0)
goto out;
lsp = request->fl_u.nfs4_fl.owner;
nlo.id = lsp->ls_id;
arg.u.lockt = &nlo;
status = rpc_call_sync(server->client, &msg, 0);
if (!status) {
@ -2654,8 +2651,7 @@ static int _nfs4_proc_getlk(struct nfs4_state *state, int cmd, struct file_lock
request->fl_pid = 0;
status = 0;
}
if (lsp)
nfs4_put_lock_state(lsp);
out:
up(&state->lock_sema);
up_read(&clp->cl_sem);
return status;
@ -2715,28 +2711,26 @@ static int _nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock
};
struct nfs4_lock_state *lsp;
struct nfs_locku_opargs luargs;
int status = 0;
int status;
down_read(&clp->cl_sem);
down(&state->lock_sema);
lsp = nfs4_find_lock_state(state, request->fl_owner);
if (!lsp)
status = nfs4_set_lock_state(state, request);
if (status != 0)
goto out;
lsp = request->fl_u.nfs4_fl.owner;
/* We might have lost the locks! */
if ((lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) {
luargs.seqid = lsp->ls_seqid;
memcpy(&luargs.stateid, &lsp->ls_stateid, sizeof(luargs.stateid));
arg.u.locku = &luargs;
status = rpc_call_sync(server->client, &msg, RPC_TASK_NOINTR);
nfs4_increment_lock_seqid(status, lsp);
}
if ((lsp->ls_flags & NFS_LOCK_INITIALIZED) == 0)
goto out;
luargs.seqid = lsp->ls_seqid;
memcpy(&luargs.stateid, &lsp->ls_stateid, sizeof(luargs.stateid));
arg.u.locku = &luargs;
status = rpc_call_sync(server->client, &msg, RPC_TASK_NOINTR);
nfs4_increment_lock_seqid(status, lsp);
if (status == 0) {
if (status == 0)
memcpy(&lsp->ls_stateid, &res.u.stateid,
sizeof(lsp->ls_stateid));
nfs4_notify_unlck(state, request, lsp);
}
nfs4_put_lock_state(lsp);
out:
up(&state->lock_sema);
if (status == 0)
@ -2762,7 +2756,7 @@ static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *r
{
struct inode *inode = state->inode;
struct nfs_server *server = NFS_SERVER(inode);
struct nfs4_lock_state *lsp;
struct nfs4_lock_state *lsp = request->fl_u.nfs4_fl.owner;
struct nfs_lockargs arg = {
.fh = NFS_FH(inode),
.type = nfs4_lck_type(cmd, request),
@ -2784,9 +2778,6 @@ static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *r
};
int status;
lsp = nfs4_get_lock_state(state, request->fl_owner);
if (lsp == NULL)
return -ENOMEM;
if (!(lsp->ls_flags & NFS_LOCK_INITIALIZED)) {
struct nfs4_state_owner *owner = state->owner;
struct nfs_open_to_lock otl = {
@ -2808,27 +2799,26 @@ static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *r
* seqid mutating errors */
nfs4_increment_seqid(status, owner);
up(&owner->so_sema);
if (status == 0) {
lsp->ls_flags |= NFS_LOCK_INITIALIZED;
lsp->ls_seqid++;
}
} else {
struct nfs_exist_lock el = {
.seqid = lsp->ls_seqid,
};
memcpy(&el.stateid, &lsp->ls_stateid, sizeof(el.stateid));
largs.u.exist_lock = &el;
largs.new_lock_owner = 0;
arg.u.lock = &largs;
status = rpc_call_sync(server->client, &msg, RPC_TASK_NOINTR);
/* increment seqid on success, and * seqid mutating errors*/
nfs4_increment_lock_seqid(status, lsp);
}
/* increment seqid on success, and * seqid mutating errors*/
nfs4_increment_lock_seqid(status, lsp);
/* save the returned stateid. */
if (status == 0) {
if (status == 0)
memcpy(&lsp->ls_stateid, &res.u.stateid, sizeof(nfs4_stateid));
lsp->ls_flags |= NFS_LOCK_INITIALIZED;
if (!reclaim)
nfs4_notify_setlk(state, request, lsp);
} else if (status == -NFS4ERR_DENIED)
else if (status == -NFS4ERR_DENIED)
status = -EAGAIN;
nfs4_put_lock_state(lsp);
return status;
}
@ -2869,7 +2859,9 @@ static int _nfs4_proc_setlk(struct nfs4_state *state, int cmd, struct file_lock
down_read(&clp->cl_sem);
down(&state->lock_sema);
status = _nfs4_do_setlk(state, cmd, request, 0);
status = nfs4_set_lock_state(state, request);
if (status == 0)
status = _nfs4_do_setlk(state, cmd, request, 0);
up(&state->lock_sema);
if (status == 0) {
/* Note: we always want to sleep here! */
@ -2927,7 +2919,6 @@ nfs4_proc_lock(struct file *filp, int cmd, struct file_lock *request)
if (signalled())
break;
} while(status < 0);
return status;
}

194
fs/nfs/nfs4state.c
View File

@ -360,7 +360,7 @@ nfs4_alloc_open_state(void)
atomic_set(&state->count, 1);
INIT_LIST_HEAD(&state->lock_states);
init_MUTEX(&state->lock_sema);
rwlock_init(&state->state_lock);
spin_lock_init(&state->state_lock);
return state;
}
@ -542,16 +542,6 @@ __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
return NULL;
}
struct nfs4_lock_state *
nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
{
struct nfs4_lock_state *lsp;
read_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, fl_owner);
read_unlock(&state->state_lock);
return lsp;
}
/*
* Return a compatible lock_state. If no initialized lock_state structure
* exists, return an uninitialized one.
@ -568,14 +558,13 @@ static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, f
return NULL;
lsp->ls_flags = 0;
lsp->ls_seqid = 0; /* arbitrary */
lsp->ls_id = -1;
memset(lsp->ls_stateid.data, 0, sizeof(lsp->ls_stateid.data));
atomic_set(&lsp->ls_count, 1);
lsp->ls_owner = fl_owner;
INIT_LIST_HEAD(&lsp->ls_locks);
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;
}
@ -585,34 +574,103 @@ static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, f
*
* The caller must be holding state->lock_sema and clp->cl_sem
*/
struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
{
struct nfs4_lock_state * lsp;
struct nfs4_lock_state *lsp, *new = NULL;
lsp = nfs4_find_lock_state(state, owner);
if (lsp == NULL)
lsp = nfs4_alloc_lock_state(state, owner);
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
*/
static 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)
void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
{
if (test_bit(LK_STATE_IN_USE, &state->flags)) {
struct nfs4_lock_state *lsp;
struct nfs4_lock_state *lsp;
lsp = nfs4_find_lock_state(state, fl_owner);
if (lsp) {
memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
nfs4_put_lock_state(lsp);
return;
}
}
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);
}
/*
@ -624,84 +682,6 @@ void nfs4_increment_lock_seqid(int status, struct nfs4_lock_state *lsp)
lsp->ls_seqid++;
}
/*
* Check to see if the request lock (type FL_UNLK) effects the fl lock.
*
* fl and request must have the same posix owner
*
* return:
* 0 -> fl not effected by request
* 1 -> fl consumed by request
*/
static int
nfs4_check_unlock(struct file_lock *fl, struct file_lock *request)
{
if (fl->fl_start >= request->fl_start && fl->fl_end <= request->fl_end)
return 1;
return 0;
}
/*
* Post an initialized lock_state on the state->lock_states list.
*/
void nfs4_notify_setlk(struct nfs4_state *state, struct file_lock *request, struct nfs4_lock_state *lsp)
{
if (!list_empty(&lsp->ls_locks))
return;
atomic_inc(&lsp->ls_count);
write_lock(&state->state_lock);
list_add(&lsp->ls_locks, &state->lock_states);
set_bit(LK_STATE_IN_USE, &state->flags);
write_unlock(&state->state_lock);
}
/*
* to decide to 'reap' lock state:
* 1) search i_flock for file_locks with fl.lock_state = to ls.
* 2) determine if unlock will consume found lock.
* if so, reap
*
* else, don't reap.
*
*/
void
nfs4_notify_unlck(struct nfs4_state *state, struct file_lock *request, struct nfs4_lock_state *lsp)
{
struct inode *inode = state->inode;
struct file_lock *fl;
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
if (!(fl->fl_flags & FL_POSIX))
continue;
if (fl->fl_owner != lsp->ls_owner)
continue;
/* Exit if we find at least one lock which is not consumed */
if (nfs4_check_unlock(fl,request) == 0)
return;
}
write_lock(&state->state_lock);
list_del_init(&lsp->ls_locks);
if (list_empty(&state->lock_states))
clear_bit(LK_STATE_IN_USE, &state->flags);
write_unlock(&state->state_lock);
nfs4_put_lock_state(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)
{
if (!atomic_dec_and_test(&lsp->ls_count))
return;
BUG_ON (!list_empty(&lsp->ls_locks));
kfree(lsp);
}
/*
* Called with sp->so_sema and clp->cl_sem held.
*

1
include/linux/fs.h
View File

@ -674,6 +674,7 @@ struct file_lock {
struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
union {
struct nfs_lock_info nfs_fl;
struct nfs4_lock_info nfs4_fl;
} fl_u;
};

5
include/linux/nfs_fs_i.h
View File

@ -16,6 +16,11 @@ struct nfs_lock_info {
struct nlm_lockowner *owner;
};
struct nfs4_lock_state;
struct nfs4_lock_info {
struct nfs4_lock_state *owner;
};
/*
* Lock flag values
*/