NFS: Don't hash the negative dentry when optimising for an O_EXCL open

We don't want to leave an unverified hashed negative dentry if the
exclusive create fails to complete.

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

2 files changed, 5 insertions, 3 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 3f0def65b8ab..166a833be661 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -992,9 +992,10 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
         }
         dentry->d_op = NFS_PROTO(dir)->dentry_ops;
 
-        /* Let vfs_create() deal with O_EXCL */
+        /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
+         * the dentry. */
         if (nd->intent.open.flags & O_EXCL) {
-                d_add(dentry, NULL);
+                d_instantiate(dentry, NULL);
                 goto out;
         }
 
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 796bc8ea7194..0748c700301d 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1879,11 +1879,12 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
         }
         state = nfs4_do_open(dir, &path, flags, sattr, cred);
         put_rpccred(cred);
+        d_drop(dentry);
         if (IS_ERR(state)) {
                 status = PTR_ERR(state);
                 goto out;
         }
-        d_instantiate(dentry, igrab(state->inode));
+        d_add(dentry, igrab(state->inode));
         if (flags & O_EXCL) {
                 struct nfs_fattr fattr;
                 status = nfs4_do_setattr(state->inode, &fattr, sattr, state);