1 files changed, 27 insertions, 84 deletions

diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 2154fa63c5f2..1582af33e204 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -542,9 +542,14 @@ static struct notifier_block nfsd_inet6addr_notifier = {
 /* Only used under nfsd_mutex, so this atomic may be overkill: */
 static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
 
-static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
+static void nfsd_last_thread(struct net *net)
 {
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+	struct svc_serv *serv = nn->nfsd_serv;
+
+	spin_lock(&nfsd_notifier_lock);
+	nn->nfsd_serv = NULL;
+	spin_unlock(&nfsd_notifier_lock);
 
 	/* check if the notifier still has clients */
 	if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
@@ -554,6 +559,8 @@ static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
 #endif
 	}
 
+	svc_xprt_destroy_all(serv, net);
+
 	/*
 	 * write_ports can create the server without actually starting
 	 * any threads--if we get shut down before any threads are
@@ -644,7 +651,8 @@ void nfsd_shutdown_threads(struct net *net)
 	svc_get(serv);
 	/* Kill outstanding nfsd threads */
 	svc_set_num_threads(serv, NULL, 0);
-	nfsd_put(net);
+	nfsd_last_thread(net);
+	svc_put(serv);
 	mutex_unlock(&nfsd_mutex);
 }
 
@@ -674,9 +682,6 @@ int nfsd_create_serv(struct net *net)
 	serv->sv_maxconn = nn->max_connections;
 	error = svc_bind(serv, net);
 	if (error < 0) {
-		/* NOT nfsd_put() as notifiers (see below) haven't
-		 * been set up yet.
-		 */
 		svc_put(serv);
 		return error;
 	}
@@ -719,29 +724,6 @@ int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
 	return 0;
 }
 
-/* This is the callback for kref_put() below.
- * There is no code here as the first thing to be done is
- * call svc_shutdown_net(), but we cannot get the 'net' from
- * the kref.  So do all the work when kref_put returns true.
- */
-static void nfsd_noop(struct kref *ref)
-{
-}
-
-void nfsd_put(struct net *net)
-{
-	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
-
-	if (kref_put(&nn->nfsd_serv->sv_refcnt, nfsd_noop)) {
-		svc_xprt_destroy_all(nn->nfsd_serv, net);
-		nfsd_last_thread(nn->nfsd_serv, net);
-		svc_destroy(&nn->nfsd_serv->sv_refcnt);
-		spin_lock(&nfsd_notifier_lock);
-		nn->nfsd_serv = NULL;
-		spin_unlock(&nfsd_notifier_lock);
-	}
-}
-
 int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
 {
 	int i = 0;
@@ -792,7 +774,7 @@ int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
 		if (err)
 			break;
 	}
-	nfsd_put(net);
+	svc_put(nn->nfsd_serv);
 	return err;
 }
 
@@ -807,6 +789,7 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
 	int	error;
 	bool	nfsd_up_before;
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+	struct svc_serv *serv;
 
 	mutex_lock(&nfsd_mutex);
 	dprintk("nfsd: creating service\n");
@@ -826,22 +809,25 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
 		goto out;
 
 	nfsd_up_before = nn->nfsd_net_up;
+	serv = nn->nfsd_serv;
 
 	error = nfsd_startup_net(net, cred);
 	if (error)
 		goto out_put;
-	error = svc_set_num_threads(nn->nfsd_serv, NULL, nrservs);
+	error = svc_set_num_threads(serv, NULL, nrservs);
 	if (error)
 		goto out_shutdown;
-	error = nn->nfsd_serv->sv_nrthreads;
+	error = serv->sv_nrthreads;
+	if (error == 0)
+		nfsd_last_thread(net);
 out_shutdown:
 	if (error < 0 && !nfsd_up_before)
 		nfsd_shutdown_net(net);
 out_put:
 	/* Threads now hold service active */
 	if (xchg(&nn->keep_active, 0))
-		nfsd_put(net);
-	nfsd_put(net);
+		svc_put(serv);
+	svc_put(serv);
 out:
 	mutex_unlock(&nfsd_mutex);
 	return error;
@@ -953,7 +939,6 @@ nfsd(void *vrqstp)
 	struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
 	struct net *net = perm_sock->xpt_net;
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
-	int err;
 
 	/* At this point, the thread shares current->fs
 	 * with the init process. We need to create files with the
@@ -965,15 +950,6 @@ nfsd(void *vrqstp)
 
 	current->fs->umask = 0;
 
-	/*
-	 * thread is spawned with all signals set to SIG_IGN, re-enable
-	 * the ones that will bring down the thread
-	 */
-	allow_signal(SIGKILL);
-	allow_signal(SIGHUP);
-	allow_signal(SIGINT);
-	allow_signal(SIGQUIT);
-
 	atomic_inc(&nfsdstats.th_cnt);
 
 	set_freezable();
@@ -981,54 +957,19 @@ nfsd(void *vrqstp)
 	/*
 	 * The main request loop
 	 */
-	for (;;) {
+	while (!kthread_should_stop()) {
 		/* Update sv_maxconn if it has changed */
 		rqstp->rq_server->sv_maxconn = nn->max_connections;
 
-		/*
-		 * Find a socket with data available and call its
-		 * recvfrom routine.
-		 */
-		while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
-			;
-		if (err == -EINTR)
-			break;
-		validate_process_creds();
-		svc_process(rqstp);
+		svc_recv(rqstp);
 		validate_process_creds();
 	}
 
-	/* Clear signals before calling svc_exit_thread() */
-	flush_signals(current);
-
 	atomic_dec(&nfsdstats.th_cnt);
 
 out:
-	/* Take an extra ref so that the svc_put in svc_exit_thread()
-	 * doesn't call svc_destroy()
-	 */
-	svc_get(nn->nfsd_serv);
-
 	/* Release the thread */
 	svc_exit_thread(rqstp);
-
-	/* We need to drop a ref, but may not drop the last reference
-	 * without holding nfsd_mutex, and we cannot wait for nfsd_mutex as that
-	 * could deadlock with nfsd_shutdown_threads() waiting for us.
-	 * So three options are:
-	 * - drop a non-final reference,
-	 * - get the mutex without waiting
-	 * - sleep briefly andd try the above again
-	 */
-	while (!svc_put_not_last(nn->nfsd_serv)) {
-		if (mutex_trylock(&nfsd_mutex)) {
-			nfsd_put(net);
-			mutex_unlock(&nfsd_mutex);
-			break;
-		}
-		msleep(20);
-	}
-
 	return 0;
 }
 
@@ -1046,6 +987,7 @@ int nfsd_dispatch(struct svc_rqst *rqstp)
 {
 	const struct svc_procedure *proc = rqstp->rq_procinfo;
 	__be32 *statp = rqstp->rq_accept_statp;
+	struct nfsd_cacherep *rp;
 
 	/*
 	 * Give the xdr decoder a chance to change this if it wants
@@ -1056,7 +998,8 @@ int nfsd_dispatch(struct svc_rqst *rqstp)
 	if (!proc->pc_decode(rqstp, &rqstp->rq_arg_stream))
 		goto out_decode_err;
 
-	switch (nfsd_cache_lookup(rqstp)) {
+	rp = NULL;
+	switch (nfsd_cache_lookup(rqstp, &rp)) {
 	case RC_DOIT:
 		break;
 	case RC_REPLY:
@@ -1072,7 +1015,7 @@ int nfsd_dispatch(struct svc_rqst *rqstp)
 	if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream))
 		goto out_encode_err;
 
-	nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
+	nfsd_cache_update(rqstp, rp, rqstp->rq_cachetype, statp + 1);
 out_cached_reply:
 	return 1;
 
@@ -1082,13 +1025,13 @@ out_decode_err:
 	return 1;
 
 out_update_drop:
-	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
+	nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL);
 out_dropit:
 	return 0;
 
 out_encode_err:
 	trace_nfsd_cant_encode_err(rqstp);
-	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
+	nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL);
 	*statp = rpc_system_err;
 	return 1;
 }