From: Alexandros Batsakis <batsakis@netapp.com>
Date: Fri, 5 Feb 2010 11:45:06 +0000 (-0800)
Subject: nfs4: renewd renew operations should take/put a client reference
X-Git-Tag: v2.6.34-rc1~190^2~5
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0851de06174e9800e76b26e4be0ca94294c09c8c;p=karo-tx-linux.git

nfs4: renewd renew operations should take/put a client reference

renewd sends RENEW requests to the NFS server in order to renew state.
As the request is asynchronous, renewd should take a reference to the
nfs_client to prevent concurrent umounts from freeing the client

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

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 663ae0c36834..68f1fe00c08c 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3152,7 +3152,9 @@ static void nfs4_renew_release(void *data)
 {
 	struct nfs_client *clp = data;
 
-	nfs4_schedule_state_renewal(clp);
+	if (atomic_read(&clp->cl_count) > 1)
+		nfs4_schedule_state_renewal(clp);
+	nfs_put_client(clp);
 }
 
 static void nfs4_renew_done(struct rpc_task *task, void *data)
@@ -3185,6 +3187,8 @@ 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, clp);
 }