NFSv4: Convert struct nfs4_state to use refcount_t

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/nfs4_fs.h

@@ -188,7 +188,7 @@ struct nfs4_state {
 	unsigned int n_wronly;		/* Number of write-only references */
 	unsigned int n_rdwr;		/* Number of read/write references */
 	fmode_t state;			/* State on the server (R,W, or RW) */
-	atomic_t count;
+	refcount_t count;
 
 	wait_queue_head_t waitq;
 	struct rcu_head rcu_head;

fs/nfs/nfs4proc.c

@@ -1777,7 +1777,7 @@ static struct nfs4_state *nfs4_try_open_cached(struct nfs4_opendata *opendata)
 out:
 	return ERR_PTR(ret);
 out_return_state:
-	atomic_inc(&state->count);
+	refcount_inc(&state->count);
 	return state;
 }
 
@@ -1849,7 +1849,7 @@ _nfs4_opendata_reclaim_to_nfs4_state(struct nfs4_opendata *data)
 update:
 	update_open_stateid(state, &data->o_res.stateid, NULL,
 			    data->o_arg.fmode);
-	atomic_inc(&state->count);
+	refcount_inc(&state->count);
 
 	return state;
 }
@@ -1887,7 +1887,7 @@ nfs4_opendata_find_nfs4_state(struct nfs4_opendata *data)
 		return ERR_CAST(inode);
 	if (data->state != NULL && data->state->inode == inode) {
 		state = data->state;
-		atomic_inc(&state->count);
+		refcount_inc(&state->count);
 	} else
 		state = nfs4_get_open_state(inode, data->owner);
 	iput(inode);
@@ -1978,7 +1978,7 @@ static struct nfs4_opendata *nfs4_open_recoverdata_alloc(struct nfs_open_context
 	if (opendata == NULL)
 		return ERR_PTR(-ENOMEM);
 	opendata->state = state;
-	atomic_inc(&state->count);
+	refcount_inc(&state->count);
 	return opendata;
 }
 

fs/nfs/nfs4state.c

@@ -655,7 +655,7 @@ nfs4_alloc_open_state(void)
 	state = kzalloc(sizeof(*state), GFP_NOFS);
 	if (!state)
 		return NULL;
-	atomic_set(&state->count, 1);
+	refcount_set(&state->count, 1);
 	INIT_LIST_HEAD(&state->lock_states);
 	spin_lock_init(&state->state_lock);
 	seqlock_init(&state->seqlock);
@@ -689,7 +689,7 @@ __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 			continue;
 		if (!nfs4_valid_open_stateid(state))
 			continue;
-		if (atomic_inc_not_zero(&state->count))
+		if (refcount_inc_not_zero(&state->count))
 			return state;
 	}
 	return NULL;
@@ -743,7 +743,7 @@ 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))
+	if (!refcount_dec_and_lock(&state->count, &owner->so_lock))
 		return;
 	spin_lock(&inode->i_lock);
 	list_del_rcu(&state->inode_states);
@@ -1573,7 +1573,7 @@ restart:
 			continue;
 		if (state->state == 0)
 			continue;
-		atomic_inc(&state->count);
+		refcount_inc(&state->count);
 		spin_unlock(&sp->so_lock);
 		status = ops->recover_open(sp, state);
 		if (status >= 0) {