NFSv4: Fix up another delegation related race

[linux-2.6-block.git] / fs / nfs / delegation.c

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index cc563cfa69407c64553d4e6730bc020df2f11790..e0cb4ee3b23eb8261e3394ca7098c8ced5e2af05 100644 (file)
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -140,13 +140,17 @@ static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfs
 
        if (delegation == NULL)
                goto nomatch;
+       spin_lock(&delegation->lock);
        if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data,
                                sizeof(delegation->stateid.data)) != 0)
-               goto nomatch;
+               goto nomatch_unlock;
        list_del_rcu(&delegation->super_list);
        nfsi->delegation_state = 0;
        rcu_assign_pointer(nfsi->delegation, NULL);
+       spin_unlock(&delegation->lock);
        return delegation;
+nomatch_unlock:
+       spin_unlock(&delegation->lock);
 nomatch:
        return NULL;
 }
@@ -172,6 +176,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
        delegation->change_attr = nfsi->change_attr;
        delegation->cred = get_rpccred(cred);
        delegation->inode = inode;
+       spin_lock_init(&delegation->lock);
 
        spin_lock(&clp->cl_lock);
        if (rcu_dereference(nfsi->delegation) != NULL) {