1 files changed, 21 insertions, 59 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index ebd07ad82431..50e9cc19023a 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -181,6 +181,7 @@ struct tun_file {
 	};
 	struct napi_struct napi;
 	bool napi_enabled;
+	bool napi_frags_enabled;
 	struct mutex napi_mutex;	/* Protects access to the above napi */
 	struct list_head next;
 	struct tun_struct *detached;
@@ -313,32 +314,32 @@ static int tun_napi_poll(struct napi_struct *napi, int budget)
 }
 
 static void tun_napi_init(struct tun_struct *tun, struct tun_file *tfile,
-			  bool napi_en)
+			  bool napi_en, bool napi_frags)
 {
 	tfile->napi_enabled = napi_en;
+	tfile->napi_frags_enabled = napi_en && napi_frags;
 	if (napi_en) {
 		netif_napi_add(tun->dev, &tfile->napi, tun_napi_poll,
 			       NAPI_POLL_WEIGHT);
 		napi_enable(&tfile->napi);
-		mutex_init(&tfile->napi_mutex);
 	}
 }
 
-static void tun_napi_disable(struct tun_struct *tun, struct tun_file *tfile)
+static void tun_napi_disable(struct tun_file *tfile)
 {
 	if (tfile->napi_enabled)
 		napi_disable(&tfile->napi);
 }
 
-static void tun_napi_del(struct tun_struct *tun, struct tun_file *tfile)
+static void tun_napi_del(struct tun_file *tfile)
 {
 	if (tfile->napi_enabled)
 		netif_napi_del(&tfile->napi);
 }
 
-static bool tun_napi_frags_enabled(const struct tun_struct *tun)
+static bool tun_napi_frags_enabled(const struct tun_file *tfile)
 {
-	return READ_ONCE(tun->flags) & IFF_NAPI_FRAGS;
+	return tfile->napi_frags_enabled;
 }
 
 #ifdef CONFIG_TUN_VNET_CROSS_LE
@@ -690,8 +691,8 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
 	tun = rtnl_dereference(tfile->tun);
 
 	if (tun && clean) {
-		tun_napi_disable(tun, tfile);
-		tun_napi_del(tun, tfile);
+		tun_napi_disable(tfile);
+		tun_napi_del(tfile);
 	}
 
 	if (tun && !tfile->detached) {
@@ -758,7 +759,7 @@ static void tun_detach_all(struct net_device *dev)
 	for (i = 0; i < n; i++) {
 		tfile = rtnl_dereference(tun->tfiles[i]);
 		BUG_ON(!tfile);
-		tun_napi_disable(tun, tfile);
+		tun_napi_disable(tfile);
 		tfile->socket.sk->sk_shutdown = RCV_SHUTDOWN;
 		tfile->socket.sk->sk_data_ready(tfile->socket.sk);
 		RCU_INIT_POINTER(tfile->tun, NULL);
@@ -774,7 +775,7 @@ static void tun_detach_all(struct net_device *dev)
 	synchronize_net();
 	for (i = 0; i < n; i++) {
 		tfile = rtnl_dereference(tun->tfiles[i]);
-		tun_napi_del(tun, tfile);
+		tun_napi_del(tfile);
 		/* Drop read queue */
 		tun_queue_purge(tfile);
 		xdp_rxq_info_unreg(&tfile->xdp_rxq);
@@ -793,7 +794,7 @@ static void tun_detach_all(struct net_device *dev)
 }
 
 static int tun_attach(struct tun_struct *tun, struct file *file,
-		      bool skip_filter, bool napi)
+		      bool skip_filter, bool napi, bool napi_frags)
 {
 	struct tun_file *tfile = file->private_data;
 	struct net_device *dev = tun->dev;
@@ -866,7 +867,7 @@ static int tun_attach(struct tun_struct *tun, struct file *file,
 		tun_enable_queue(tfile);
 	} else {
 		sock_hold(&tfile->sk);
-		tun_napi_init(tun, tfile, napi);
+		tun_napi_init(tun, tfile, napi, napi_frags);
 	}
 
 	tun_set_real_num_queues(tun);
@@ -1153,43 +1154,6 @@ static netdev_features_t tun_net_fix_features(struct net_device *dev,
 
 	return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
 }
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void tun_poll_controller(struct net_device *dev)
-{
-	/*
-	 * Tun only receives frames when:
-	 * 1) the char device endpoint gets data from user space
-	 * 2) the tun socket gets a sendmsg call from user space
-	 * If NAPI is not enabled, since both of those are synchronous
-	 * operations, we are guaranteed never to have pending data when we poll
-	 * for it so there is nothing to do here but return.
-	 * We need this though so netpoll recognizes us as an interface that
-	 * supports polling, which enables bridge devices in virt setups to
-	 * still use netconsole
-	 * If NAPI is enabled, however, we need to schedule polling for all
-	 * queues unless we are using napi_gro_frags(), which we call in
-	 * process context and not in NAPI context.
-	 */
-	struct tun_struct *tun = netdev_priv(dev);
-
-	if (tun->flags & IFF_NAPI) {
-		struct tun_file *tfile;
-		int i;
-
-		if (tun_napi_frags_enabled(tun))
-			return;
-
-		rcu_read_lock();
-		for (i = 0; i < tun->numqueues; i++) {
-			tfile = rcu_dereference(tun->tfiles[i]);
-			if (tfile->napi_enabled)
-				napi_schedule(&tfile->napi);
-		}
-		rcu_read_unlock();
-	}
-	return;
-}
-#endif
 
 static void tun_set_headroom(struct net_device *dev, int new_hr)
 {
@@ -1283,9 +1247,6 @@ static const struct net_device_ops tun_netdev_ops = {
 	.ndo_start_xmit		= tun_net_xmit,
 	.ndo_fix_features	= tun_net_fix_features,
 	.ndo_select_queue	= tun_select_queue,
-#ifdef CONFIG_NET_POLL_CONTROLLER
-	.ndo_poll_controller	= tun_poll_controller,
-#endif
 	.ndo_set_rx_headroom	= tun_set_headroom,
 	.ndo_get_stats64	= tun_net_get_stats64,
 };
@@ -1365,9 +1326,6 @@ static const struct net_device_ops tap_netdev_ops = {
 	.ndo_set_mac_address	= eth_mac_addr,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_select_queue	= tun_select_queue,
-#ifdef CONFIG_NET_POLL_CONTROLLER
-	.ndo_poll_controller	= tun_poll_controller,
-#endif
 	.ndo_features_check	= passthru_features_check,
 	.ndo_set_rx_headroom	= tun_set_headroom,
 	.ndo_get_stats64	= tun_net_get_stats64,
@@ -1752,7 +1710,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 	int err;
 	u32 rxhash = 0;
 	int skb_xdp = 1;
-	bool frags = tun_napi_frags_enabled(tun);
+	bool frags = tun_napi_frags_enabled(tfile);
 
 	if (!(tun->dev->flags & IFF_UP))
 		return -EIO;
@@ -2577,7 +2535,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
 			return err;
 
 		err = tun_attach(tun, file, ifr->ifr_flags & IFF_NOFILTER,
-				 ifr->ifr_flags & IFF_NAPI);
+				 ifr->ifr_flags & IFF_NAPI,
+				 ifr->ifr_flags & IFF_NAPI_FRAGS);
 		if (err < 0)
 			return err;
 
@@ -2675,7 +2634,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
 			      (ifr->ifr_flags & TUN_FEATURES);
 
 		INIT_LIST_HEAD(&tun->disabled);
-		err = tun_attach(tun, file, false, ifr->ifr_flags & IFF_NAPI);
+		err = tun_attach(tun, file, false, ifr->ifr_flags & IFF_NAPI,
+				 ifr->ifr_flags & IFF_NAPI_FRAGS);
 		if (err < 0)
 			goto err_free_flow;
 
@@ -2824,7 +2784,8 @@ static int tun_set_queue(struct file *file, struct ifreq *ifr)
 		ret = security_tun_dev_attach_queue(tun->security);
 		if (ret < 0)
 			goto unlock;
-		ret = tun_attach(tun, file, false, tun->flags & IFF_NAPI);
+		ret = tun_attach(tun, file, false, tun->flags & IFF_NAPI,
+				 tun->flags & IFF_NAPI_FRAGS);
 	} else if (ifr->ifr_flags & IFF_DETACH_QUEUE) {
 		tun = rtnl_dereference(tfile->tun);
 		if (!tun || !(tun->flags & IFF_MULTI_QUEUE) || tfile->detached)
@@ -3242,6 +3203,7 @@ static int tun_chr_open(struct inode *inode, struct file * file)
 		return -ENOMEM;
 	}
 
+	mutex_init(&tfile->napi_mutex);
 	RCU_INIT_POINTER(tfile->tun, NULL);
 	tfile->flags = 0;
 	tfile->ifindex = 0;