nfsd: handle errors from rpc_call_async()

It's possible for rpc_call_async() to fail (mainly due to memory
allocation failure). If it does, there isn't much recourse other than to
requeue the callback and try again later.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 018533bb83a3ca6fda46e072eebca6d2583c393a..3f21de06154e3f80818c85a92d6044058339697f 100644 (file)
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1592,7 +1592,7 @@ nfsd4_run_cb_work(struct work_struct *work)
                container_of(work, struct nfsd4_callback, cb_work);
        struct nfs4_client *clp = cb->cb_clp;
        struct rpc_clnt *clnt;
-       int flags;
+       int flags, ret;
 
        trace_nfsd_cb_start(clp);
 
@@ -1625,8 +1625,12 @@ nfsd4_run_cb_work(struct work_struct *work)
 
        cb->cb_msg.rpc_cred = clp->cl_cb_cred;
        flags = clp->cl_minorversion ? RPC_TASK_NOCONNECT : RPC_TASK_SOFTCONN;
-       rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | flags,
-                       cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb);
+       ret = rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | flags,
+                            cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb);
+       if (ret != 0) {
+               set_bit(NFSD4_CALLBACK_REQUEUE, &cb->cb_flags);
+               nfsd4_queue_cb(cb);
+       }
 }
 
 void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,