[PATCH 3/4] nfs41: fix race between umount and renewd sequence operations

[Alexandros Batsakis <batsakis@netapp.com>]

Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
---
 fs/nfs/nfs4proc.c |   18 ++++++++++++++++--
 1 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 9fc99e9..cd523df 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5041,6 +5041,8 @@ void nfs41_sequence_call_done(struct rpc_task *task, void *data)
 
 	if (task->tk_status < 0) {
 		dprintk("%s ERROR %d\n", __func__, task->tk_status);
+		if (atomic_read(&clp->cl_count) == 1)
+			return;
 
 		if (_nfs4_async_handle_error(task, NULL, clp, NULL)
 								== -EAGAIN) {
@@ -5050,7 +5052,8 @@ void nfs41_sequence_call_done(struct rpc_task *task, void *data)
 	}
 	dprintk("%s rpc_cred %p\n", __func__, task->tk_msg.rpc_cred);
 
-	nfs4_schedule_state_renewal(clp);
+	if (atomic_read(&clp->cl_count) > 1)
+		nfs4_schedule_state_renewal(clp);
 
 	kfree(task->tk_msg.rpc_argp);
 	kfree(task->tk_msg.rpc_resp);
@@ -5073,9 +5076,15 @@ static void nfs41_sequence_prepare(struct rpc_task *task, void *data)
 	rpc_call_start(task);
 }
 
+static void nfs41_sequence_release(void *calldata)
+{
+	nfs_put_client((struct nfs_client *) calldata);
+}
+
 static const struct rpc_call_ops nfs41_sequence_ops = {
 	.rpc_call_done = nfs41_sequence_call_done,
 	.rpc_call_prepare = nfs41_sequence_prepare,
+	.rpc_release = nfs41_sequence_release,
 };
 
 static int nfs41_proc_async_sequence(struct nfs_client *clp,
@@ -5088,11 +5097,16 @@ static int nfs41_proc_async_sequence(struct nfs_client *clp,
 		.rpc_cred = cred,
 	};
 
+	if (!atomic_inc_not_zero(&clp->cl_count))
+		return -EIO;
 	args = kzalloc(sizeof(*args), GFP_KERNEL);
-	if (!args)
+	if (!args) {
+		nfs_put_client(clp);
 		return -ENOMEM;
+	}
 	res = kzalloc(sizeof(*res), GFP_KERNEL);
 	if (!res) {
+		nfs_put_client(clp);
 		kfree(args);
 		return -ENOMEM;
 	}
-- 
1.6.2.5