NFSv4: nfs4_callback_getattr() should ignore revoked delegations

If the delegation has been revoked, ignore it.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/callback_proc.c

@@ -26,7 +26,6 @@ __be32 nfs4_callback_getattr(void *argp, void *resp,
 	struct cb_getattrargs *args = argp;
 	struct cb_getattrres *res = resp;
 	struct nfs_delegation *delegation;
-	struct nfs_inode *nfsi;
 	struct inode *inode;
 
 	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
@@ -47,9 +46,8 @@ __be32 nfs4_callback_getattr(void *argp, void *resp,
 				-ntohl(res->status));
 		goto out;
 	}
-	nfsi = NFS_I(inode);
 	rcu_read_lock();
-	delegation = rcu_dereference(nfsi->delegation);
+	delegation = nfs4_get_valid_delegation(inode);
 	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
 		goto out_iput;
 	res->size = i_size_read(inode);