NFS: Use atomic bitops when changing struct nfs_delegation->flags

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/delegation.c

@@ -119,7 +119,7 @@ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, st
 	delegation->maxsize = res->maxsize;
 	oldcred = delegation->cred;
 	delegation->cred = get_rpccred(cred);
-	delegation->flags &= ~NFS_DELEGATION_NEED_RECLAIM;
+	clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
 	NFS_I(inode)->delegation_state = delegation->type;
 	smp_wmb();
 	put_rpccred(oldcred);
@@ -499,7 +499,7 @@ void nfs_delegation_mark_reclaim(struct nfs_client *clp)
 	struct nfs_delegation *delegation;
 	rcu_read_lock();
 	list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list)
-		delegation->flags |= NFS_DELEGATION_NEED_RECLAIM;
+		set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
 	rcu_read_unlock();
 }
 
@@ -513,7 +513,7 @@ void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
 restart:
 	rcu_read_lock();
 	list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
-		if ((delegation->flags & NFS_DELEGATION_NEED_RECLAIM) == 0)
+		if (test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) == 0)
 			continue;
 		inode = nfs_delegation_grab_inode(delegation);
 		if (inode == NULL)

fs/nfs/delegation.h

@@ -18,10 +18,10 @@ struct nfs_delegation {
 	struct inode *inode;
 	nfs4_stateid stateid;
 	int type;
-#define NFS_DELEGATION_NEED_RECLAIM 1
-	long flags;
 	loff_t maxsize;
 	__u64 change_attr;
+#define NFS_DELEGATION_NEED_RECLAIM 0
+	unsigned long flags;
 	spinlock_t lock;
 	struct rcu_head rcu;
 };

fs/nfs/nfs4proc.c

@@ -344,7 +344,7 @@ static int can_open_delegated(struct nfs_delegation *delegation, mode_t open_fla
 {
 	if ((delegation->type & open_flags) != open_flags)
 		return 0;
-	if (delegation->flags & NFS_DELEGATION_NEED_RECLAIM)
+	if (test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags))
 		return 0;
 	return 1;
 }
@@ -536,7 +536,7 @@ static struct nfs4_state *nfs4_opendata_to_nfs4_state(struct nfs4_opendata *data
 		if (delegation)
 			delegation_flags = delegation->flags;
 		rcu_read_unlock();
-		if (!(delegation_flags & NFS_DELEGATION_NEED_RECLAIM))
+		if ((delegation_flags & 1UL<<NFS_DELEGATION_NEED_RECLAIM) == 0)
 			nfs_inode_set_delegation(state->inode,
 					data->owner->so_cred,
 					&data->o_res);
@@ -667,7 +667,7 @@ static int _nfs4_do_open_reclaim(struct nfs_open_context *ctx, struct nfs4_state
 	opendata->o_arg.fh = NFS_FH(state->inode);
 	rcu_read_lock();
 	delegation = rcu_dereference(NFS_I(state->inode)->delegation);
-	if (delegation != NULL && (delegation->flags & NFS_DELEGATION_NEED_RECLAIM) != 0)
+	if (delegation != NULL && test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) != 0)
 		delegation_type = delegation->type;
 	rcu_read_unlock();
 	opendata->o_arg.u.delegation_type = delegation_type;
@@ -839,7 +839,7 @@ static void nfs4_open_prepare(struct rpc_task *task, void *calldata)
 		rcu_read_lock();
 		delegation = rcu_dereference(NFS_I(data->state->inode)->delegation);
 		if (delegation != NULL &&
-		   (delegation->flags & NFS_DELEGATION_NEED_RECLAIM) == 0) {
+		    test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) == 0) {
 			rcu_read_unlock();
 			goto out_no_action;
 		}