NLM,NFSv4: Don't put UNLOCK requests on the wire unless we hold a lock

Use the new behaviour of {flock,posix}_file_lock(F_UNLCK) to determine if
we held a lock, and only send the RPC request to the server if this was the
case.

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

1 files changed, 12 insertions, 19 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b4916b092194..b8c63757f039 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3144,9 +3144,6 @@ static int do_vfs_lock(struct file *file, struct file_lock *fl)
 		default:
 			BUG();
 	}
-	if (res < 0)
-		printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n",
-				__FUNCTION__);
 	return res;
 }
 
@@ -3258,8 +3255,6 @@ static struct rpc_task *nfs4_do_unlck(struct file_lock *fl,
 		return ERR_PTR(-ENOMEM);
 	}
 
-	/* Unlock _before_ we do the RPC call */
-	do_vfs_lock(fl->fl_file, fl);
 	return rpc_run_task(NFS_CLIENT(lsp->ls_state->inode), RPC_TASK_ASYNC, &nfs4_locku_ops, data);
 }
 
@@ -3270,30 +3265,28 @@ static int nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock *
 	struct rpc_task *task;
 	int status = 0;
 
-	/* Is this a delegated lock? */
-	if (test_bit(NFS_DELEGATED_STATE, &state->flags))
-		goto out_unlock;
-	/* Is this open_owner holding any locks on the server? */
-	if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
-		goto out_unlock;
-
 	status = nfs4_set_lock_state(state, request);
+	/* Unlock _before_ we do the RPC call */
+	request->fl_flags |= FL_EXISTS;
+	if (do_vfs_lock(request->fl_file, request) == -ENOENT)
+		goto out;
 	if (status != 0)
-		goto out_unlock;
+		goto out;
+	/* Is this a delegated lock? */
+	if (test_bit(NFS_DELEGATED_STATE, &state->flags))
+		goto out;
 	lsp = request->fl_u.nfs4_fl.owner;
-	status = -ENOMEM;
 	seqid = nfs_alloc_seqid(&lsp->ls_seqid);
+	status = -ENOMEM;
 	if (seqid == NULL)
-		goto out_unlock;
+		goto out;
 	task = nfs4_do_unlck(request, request->fl_file->private_data, lsp, seqid);
 	status = PTR_ERR(task);
 	if (IS_ERR(task))
-		goto out_unlock;
+		goto out;
 	status = nfs4_wait_for_completion_rpc_task(task);
 	rpc_release_task(task);
-	return status;
-out_unlock:
-	do_vfs_lock(request->fl_file, request);
+out:
 	return status;
 }