1 files changed, 138 insertions, 95 deletions

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index bac973a..194d865 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -208,6 +208,35 @@ static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl,
 	return xcl->xcl_ops->xpo_create(serv, net, sap, len, flags);
 }
 
+/*
+ * svc_xprt_received conditionally queues the transport for processing
+ * by another thread. The caller must hold the XPT_BUSY bit and must
+ * not thereafter touch transport data.
+ *
+ * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
+ * insufficient) data.
+ */
+static void svc_xprt_received(struct svc_xprt *xprt)
+{
+	BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
+	/* As soon as we clear busy, the xprt could be closed and
+	 * 'put', so we need a reference to call svc_xprt_enqueue with:
+	 */
+	svc_xprt_get(xprt);
+	clear_bit(XPT_BUSY, &xprt->xpt_flags);
+	svc_xprt_enqueue(xprt);
+	svc_xprt_put(xprt);
+}
+
+void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *new)
+{
+	clear_bit(XPT_TEMP, &new->xpt_flags);
+	spin_lock_bh(&serv->sv_lock);
+	list_add(&new->xpt_list, &serv->sv_permsocks);
+	spin_unlock_bh(&serv->sv_lock);
+	svc_xprt_received(new);
+}
+
 int svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
 		    struct net *net, const int family,
 		    const unsigned short port, int flags)
@@ -232,13 +261,8 @@ int svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
 			module_put(xcl->xcl_owner);
 			return PTR_ERR(newxprt);
 		}
-
-		clear_bit(XPT_TEMP, &newxprt->xpt_flags);
-		spin_lock_bh(&serv->sv_lock);
-		list_add(&newxprt->xpt_list, &serv->sv_permsocks);
-		spin_unlock_bh(&serv->sv_lock);
+		svc_add_new_perm_xprt(serv, newxprt);
 		newport = svc_xprt_local_port(newxprt);
-		clear_bit(XPT_BUSY, &newxprt->xpt_flags);
 		return newport;
 	}
  err:
@@ -394,27 +418,6 @@ static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
 	return xprt;
 }
 
-/*
- * svc_xprt_received conditionally queues the transport for processing
- * by another thread. The caller must hold the XPT_BUSY bit and must
- * not thereafter touch transport data.
- *
- * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
- * insufficient) data.
- */
-void svc_xprt_received(struct svc_xprt *xprt)
-{
-	BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
-	/* As soon as we clear busy, the xprt could be closed and
-	 * 'put', so we need a reference to call svc_xprt_enqueue with:
-	 */
-	svc_xprt_get(xprt);
-	clear_bit(XPT_BUSY, &xprt->xpt_flags);
-	svc_xprt_enqueue(xprt);
-	svc_xprt_put(xprt);
-}
-EXPORT_SYMBOL_GPL(svc_xprt_received);
-
 /**
  * svc_reserve - change the space reserved for the reply to a request.
  * @rqstp:  The request in question
@@ -565,33 +568,12 @@ static void svc_check_conn_limits(struct svc_serv *serv)
 	}
 }
 
-/*
- * Receive the next request on any transport.  This code is carefully
- * organised not to touch any cachelines in the shared svc_serv
- * structure, only cachelines in the local svc_pool.
- */
-int svc_recv(struct svc_rqst *rqstp, long timeout)
+int svc_alloc_arg(struct svc_rqst *rqstp)
 {
-	struct svc_xprt		*xprt = NULL;
-	struct svc_serv		*serv = rqstp->rq_server;
-	struct svc_pool		*pool = rqstp->rq_pool;
-	int			len, i;
-	int			pages;
-	struct xdr_buf		*arg;
-	DECLARE_WAITQUEUE(wait, current);
-	long			time_left;
-
-	dprintk("svc: server %p waiting for data (to = %ld)\n",
-		rqstp, timeout);
-
-	if (rqstp->rq_xprt)
-		printk(KERN_ERR
-			"svc_recv: service %p, transport not NULL!\n",
-			 rqstp);
-	if (waitqueue_active(&rqstp->rq_wait))
-		printk(KERN_ERR
-			"svc_recv: service %p, wait queue active!\n",
-			 rqstp);
+	struct svc_serv *serv = rqstp->rq_server;
+	struct xdr_buf *arg;
+	int pages;
+	int i;
 
 	/* now allocate needed pages.  If we get a failure, sleep briefly */
 	pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE;
@@ -621,11 +603,15 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 	arg->page_len = (pages-2)*PAGE_SIZE;
 	arg->len = (pages-1)*PAGE_SIZE;
 	arg->tail[0].iov_len = 0;
+	return 0;
+}
 
-	try_to_freeze();
-	cond_resched();
-	if (signalled() || kthread_should_stop())
-		return -EINTR;
+struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
+{
+	struct svc_xprt *xprt;
+	struct svc_pool		*pool = rqstp->rq_pool;
+	DECLARE_WAITQUEUE(wait, current);
+	long			time_left;
 
 	/* Normally we will wait up to 5 seconds for any required
 	 * cache information to be provided.
@@ -663,7 +649,7 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 		if (kthread_should_stop()) {
 			set_current_state(TASK_RUNNING);
 			spin_unlock_bh(&pool->sp_lock);
-			return -EINTR;
+			return ERR_PTR(-EINTR);
 		}
 
 		add_wait_queue(&rqstp->rq_wait, &wait);
@@ -684,48 +670,58 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 			spin_unlock_bh(&pool->sp_lock);
 			dprintk("svc: server %p, no data yet\n", rqstp);
 			if (signalled() || kthread_should_stop())
-				return -EINTR;
+				return ERR_PTR(-EINTR);
 			else
-				return -EAGAIN;
+				return ERR_PTR(-EAGAIN);
 		}
 	}
 	spin_unlock_bh(&pool->sp_lock);
+	return xprt;
+}
+
+void svc_add_new_temp_xprt(struct svc_serv *serv, struct svc_xprt *newxpt)
+{
+	spin_lock_bh(&serv->sv_lock);
+	set_bit(XPT_TEMP, &newxpt->xpt_flags);
+	list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
+	serv->sv_tmpcnt++;
+	if (serv->sv_temptimer.function == NULL) {
+		/* setup timer to age temp transports */
+		setup_timer(&serv->sv_temptimer, svc_age_temp_xprts,
+			    (unsigned long)serv);
+		mod_timer(&serv->sv_temptimer,
+			  jiffies + svc_conn_age_period * HZ);
+	}
+	spin_unlock_bh(&serv->sv_lock);
+	svc_xprt_received(newxpt);
+}
+
+static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt)
+{
+	struct svc_serv *serv = rqstp->rq_server;
+	int len = 0;
 
-	len = 0;
 	if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
 		dprintk("svc_recv: found XPT_CLOSE\n");
 		svc_delete_xprt(xprt);
 		/* Leave XPT_BUSY set on the dead xprt: */
-		goto out;
+		return 0;
 	}
 	if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
 		struct svc_xprt *newxpt;
+		/*
+		 * We know this module_get will succeed because the
+		 * listener holds a reference too
+		 */
+		__module_get(xprt->xpt_class->xcl_owner);
+		svc_check_conn_limits(xprt->xpt_server);
 		newxpt = xprt->xpt_ops->xpo_accept(xprt);
-		if (newxpt) {
-			/*
-			 * We know this module_get will succeed because the
-			 * listener holds a reference too
-			 */
-			__module_get(newxpt->xpt_class->xcl_owner);
-			svc_check_conn_limits(xprt->xpt_server);
-			spin_lock_bh(&serv->sv_lock);
-			set_bit(XPT_TEMP, &newxpt->xpt_flags);
-			list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
-			serv->sv_tmpcnt++;
-			if (serv->sv_temptimer.function == NULL) {
-				/* setup timer to age temp transports */
-				setup_timer(&serv->sv_temptimer,
-					    svc_age_temp_xprts,
-					    (unsigned long)serv);
-				mod_timer(&serv->sv_temptimer,
-					  jiffies + svc_conn_age_period * HZ);
-			}
-			spin_unlock_bh(&serv->sv_lock);
-			svc_xprt_received(newxpt);
-		}
+		if (newxpt)
+			svc_add_new_temp_xprt(serv, newxpt);
 	} else if (xprt->xpt_ops->xpo_has_wspace(xprt)) {
+		/* XPT_DATA|XPT_DEFERRED case: */
 		dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
-			rqstp, pool->sp_id, xprt,
+			rqstp, rqstp->rq_pool->sp_id, xprt,
 			atomic_read(&xprt->xpt_ref.refcount));
 		rqstp->rq_deferred = svc_deferred_dequeue(xprt);
 		if (rqstp->rq_deferred)
@@ -736,10 +732,51 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 		rqstp->rq_reserved = serv->sv_max_mesg;
 		atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
 	}
+	/* clear XPT_BUSY: */
 	svc_xprt_received(xprt);
+	return len;
+}
+
+/*
+ * Receive the next request on any transport.  This code is carefully
+ * organised not to touch any cachelines in the shared svc_serv
+ * structure, only cachelines in the local svc_pool.
+ */
+int svc_recv(struct svc_rqst *rqstp, long timeout)
+{
+	struct svc_xprt		*xprt = NULL;
+	struct svc_serv		*serv = rqstp->rq_server;
+	int			len, err;
+
+	dprintk("svc: server %p waiting for data (to = %ld)\n",
+		rqstp, timeout);
+
+	if (rqstp->rq_xprt)
+		printk(KERN_ERR
+			"svc_recv: service %p, transport not NULL!\n",
+			 rqstp);
+	if (waitqueue_active(&rqstp->rq_wait))
+		printk(KERN_ERR
+			"svc_recv: service %p, wait queue active!\n",
+			 rqstp);
+
+	err = svc_alloc_arg(rqstp);
+	if (err)
+		return err;
+
+	try_to_freeze();
+	cond_resched();
+	if (signalled() || kthread_should_stop())
+		return -EINTR;
+
+	xprt = svc_get_next_xprt(rqstp, timeout);
+	if (IS_ERR(xprt))
+		return PTR_ERR(xprt);
+
+	len = svc_handle_xprt(rqstp, xprt);
 
 	/* No data, incomplete (TCP) read, or accept() */
-	if (len == 0 || len == -EAGAIN)
+	if (len <= 0)
 		goto out;
 
 	clear_bit(XPT_OLD, &xprt->xpt_flags);
@@ -917,16 +954,18 @@ void svc_close_xprt(struct svc_xprt *xprt)
 }
 EXPORT_SYMBOL_GPL(svc_close_xprt);
 
-static void svc_close_list(struct list_head *xprt_list, struct net *net)
+static void svc_close_list(struct svc_serv *serv, struct list_head *xprt_list, struct net *net)
 {
 	struct svc_xprt *xprt;
 
+	spin_lock(&serv->sv_lock);
 	list_for_each_entry(xprt, xprt_list, xpt_list) {
 		if (xprt->xpt_net != net)
 			continue;
 		set_bit(XPT_CLOSE, &xprt->xpt_flags);
 		set_bit(XPT_BUSY, &xprt->xpt_flags);
 	}
+	spin_unlock(&serv->sv_lock);
 }
 
 static void svc_clear_pools(struct svc_serv *serv, struct net *net)
@@ -949,24 +988,28 @@ static void svc_clear_pools(struct svc_serv *serv, struct net *net)
 	}
 }
 
-static void svc_clear_list(struct list_head *xprt_list, struct net *net)
+static void svc_clear_list(struct svc_serv *serv, struct list_head *xprt_list, struct net *net)
 {
 	struct svc_xprt *xprt;
 	struct svc_xprt *tmp;
+	LIST_HEAD(victims);
 
+	spin_lock(&serv->sv_lock);
 	list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
 		if (xprt->xpt_net != net)
 			continue;
-		svc_delete_xprt(xprt);
+		list_move(&xprt->xpt_list, &victims);
 	}
-	list_for_each_entry(xprt, xprt_list, xpt_list)
-		BUG_ON(xprt->xpt_net == net);
+	spin_unlock(&serv->sv_lock);
+
+	list_for_each_entry_safe(xprt, tmp, &victims, xpt_list)
+		svc_delete_xprt(xprt);
 }
 
 void svc_close_net(struct svc_serv *serv, struct net *net)
 {
-	svc_close_list(&serv->sv_tempsocks, net);
-	svc_close_list(&serv->sv_permsocks, net);
+	svc_close_list(serv, &serv->sv_tempsocks, net);
+	svc_close_list(serv, &serv->sv_permsocks, net);
 
 	svc_clear_pools(serv, net);
 	/*
@@ -974,8 +1017,8 @@ void svc_close_net(struct svc_serv *serv, struct net *net)
 	 * svc_xprt_enqueue will not add new entries without taking the
 	 * sp_lock and checking XPT_BUSY.
 	 */
-	svc_clear_list(&serv->sv_tempsocks, net);
-	svc_clear_list(&serv->sv_permsocks, net);
+	svc_clear_list(serv, &serv->sv_tempsocks, net);
+	svc_clear_list(serv, &serv->sv_permsocks, net);
 }
 
 /*