[PATCH 4/4] nfs4: fix race between umount and renew operations

[Alexandros Batsakis <batsakis@netapp.com>]

Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
---
 fs/nfs/nfs4proc.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index cd523df..cc8f059 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3162,11 +3162,18 @@ static void nfs4_renew_done(struct rpc_task *task, void *data)
 	if (time_before(clp->cl_last_renewal,timestamp))
 		clp->cl_last_renewal = timestamp;
 	spin_unlock(&clp->cl_lock);
-	nfs4_schedule_state_renewal(clp);
+	if (atomic_read(clp->cl_count) > 1)
+		nfs4_schedule_state_renewal(clp);
+}
+
+static void nfs4_renew_release(void *calldata)
+{
+	nfs_put_client((struct nfs_client *) calldata);
 }
 
 static const struct rpc_call_ops nfs4_renew_ops = {
 	.rpc_call_done = nfs4_renew_done,
+	.rpc_release = nfs4_renew_release,
 };
 
 int nfs4_proc_async_renew(struct nfs_client *clp, struct rpc_cred *cred)
@@ -3177,6 +3184,9 @@ int nfs4_proc_async_renew(struct nfs_client *clp, struct rpc_cred *cred)
 		.rpc_cred	= cred,
 	};
 
+	if (!atomic_inc_not_zero(clp->cl_count))
+		return -EIO;
+
 	return rpc_call_async(clp->cl_rpcclient, &msg, RPC_TASK_SOFT,
 			&nfs4_renew_ops, (void *)jiffies);
 }
-- 
1.6.2.5