X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=net%2Fpacket%2Faf_packet.c;h=9d70f1349926c13c21d62326d2b501c6f83472c3;hb=d346a3fae3ff;hp=2e8286b47c28e5bef7cb80162e12ddb8ca4b358e;hpb=267666ea3bd6e804c2c8bbafbe628026be963d06;p=cascardo%2Flinux.git

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 2e8286b47c28..9d70f1349926 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -237,6 +237,82 @@ struct packet_skb_cb {
 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
 static void __fanout_link(struct sock *sk, struct packet_sock *po);
 
+static int packet_direct_xmit(struct sk_buff *skb)
+{
+	struct net_device *dev = skb->dev;
+	const struct net_device_ops *ops = dev->netdev_ops;
+	netdev_features_t features;
+	struct netdev_queue *txq;
+	u16 queue_map;
+	int ret;
+
+	if (unlikely(!netif_running(dev) ||
+		     !netif_carrier_ok(dev))) {
+		kfree_skb(skb);
+		return NET_XMIT_DROP;
+	}
+
+	features = netif_skb_features(skb);
+	if (skb_needs_linearize(skb, features) &&
+	    __skb_linearize(skb)) {
+		kfree_skb(skb);
+		return NET_XMIT_DROP;
+	}
+
+	queue_map = skb_get_queue_mapping(skb);
+	txq = netdev_get_tx_queue(dev, queue_map);
+
+	__netif_tx_lock_bh(txq);
+	if (unlikely(netif_xmit_frozen_or_stopped(txq))) {
+		ret = NETDEV_TX_BUSY;
+		kfree_skb(skb);
+		goto out;
+	}
+
+	ret = ops->ndo_start_xmit(skb, dev);
+	if (likely(dev_xmit_complete(ret)))
+		txq_trans_update(txq);
+	else
+		kfree_skb(skb);
+out:
+	__netif_tx_unlock_bh(txq);
+	return ret;
+}
+
+static struct net_device *packet_cached_dev_get(struct packet_sock *po)
+{
+	struct net_device *dev;
+
+	rcu_read_lock();
+	dev = rcu_dereference(po->cached_dev);
+	if (likely(dev))
+		dev_hold(dev);
+	rcu_read_unlock();
+
+	return dev;
+}
+
+static void packet_cached_dev_assign(struct packet_sock *po,
+				     struct net_device *dev)
+{
+	rcu_assign_pointer(po->cached_dev, dev);
+}
+
+static void packet_cached_dev_reset(struct packet_sock *po)
+{
+	RCU_INIT_POINTER(po->cached_dev, NULL);
+}
+
+static bool packet_use_direct_xmit(const struct packet_sock *po)
+{
+	return po->xmit == packet_direct_xmit;
+}
+
+static u16 packet_pick_tx_queue(struct net_device *dev)
+{
+	return (u16) smp_processor_id() % dev->real_num_tx_queues;
+}
+
 /* register_prot_hook must be invoked with the po->bind_lock held,
  * or from a context in which asynchronous accesses to the packet
  * socket is not possible (packet_create()).
@@ -244,11 +320,13 @@ static void __fanout_link(struct sock *sk, struct packet_sock *po);
 static void register_prot_hook(struct sock *sk)
 {
 	struct packet_sock *po = pkt_sk(sk);
+
 	if (!po->running) {
 		if (po->fanout)
 			__fanout_link(sk, po);
 		else
 			dev_add_pack(&po->prot_hook);
+
 		sock_hold(sk);
 		po->running = 1;
 	}
@@ -266,10 +344,12 @@ static void __unregister_prot_hook(struct sock *sk, bool sync)
 	struct packet_sock *po = pkt_sk(sk);
 
 	po->running = 0;
+
 	if (po->fanout)
 		__fanout_unlink(sk, po);
 	else
 		__dev_remove_pack(&po->prot_hook);
+
 	__sock_put(sk);
 
 	if (sync) {
@@ -430,11 +510,12 @@ static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
 {
 	struct tpacket_kbdq_core *pkc;
 
-	pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
+	pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
+			GET_PBDQC_FROM_RB(&po->rx_ring);
 
-	spin_lock(&rb_queue->lock);
+	spin_lock_bh(&rb_queue->lock);
 	pkc->delete_blk_timer = 1;
-	spin_unlock(&rb_queue->lock);
+	spin_unlock_bh(&rb_queue->lock);
 
 	prb_del_retire_blk_timer(pkc);
 }
@@ -456,7 +537,8 @@ static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
 	if (tx_ring)
 		BUG();
 
-	pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
+	pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
+			GET_PBDQC_FROM_RB(&po->rx_ring);
 	prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
 }
 
@@ -514,7 +596,7 @@ static void init_prb_bdqc(struct packet_sock *po,
 			struct pgv *pg_vec,
 			union tpacket_req_u *req_u, int tx_ring)
 {
-	struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
+	struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
 	struct tpacket_block_desc *pbd;
 
 	memset(p1, 0x0, sizeof(*p1));
@@ -578,7 +660,7 @@ static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 static void prb_retire_rx_blk_timer_expired(unsigned long data)
 {
 	struct packet_sock *po = (struct packet_sock *)data;
-	struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
+	struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
 	unsigned int frozen;
 	struct tpacket_block_desc *pbd;
 
@@ -1964,9 +2046,10 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
 
 	skb_reserve(skb, hlen);
 	skb_reset_network_header(skb);
-	skb_probe_transport_header(skb, 0);
 
-	if (po->tp_tx_has_off) {
+	if (!packet_use_direct_xmit(po))
+		skb_probe_transport_header(skb, 0);
+	if (unlikely(po->tp_tx_has_off)) {
 		int off_min, off_max, off;
 		off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
 		off_max = po->tx_ring.frame_size - tp_len;
@@ -2057,7 +2140,6 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
 	struct sk_buff *skb;
 	struct net_device *dev;
 	__be16 proto;
-	bool need_rls_dev = false;
 	int err, reserve = 0;
 	void *ph;
 	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
@@ -2069,8 +2151,8 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
 
 	mutex_lock(&po->pg_vec_lock);
 
-	if (saddr == NULL) {
-		dev = po->prot_hook.dev;
+	if (likely(saddr == NULL)) {
+		dev	= packet_cached_dev_get(po);
 		proto	= po->num;
 		addr	= NULL;
 	} else {
@@ -2084,19 +2166,17 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
 		proto	= saddr->sll_protocol;
 		addr	= saddr->sll_addr;
 		dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
-		need_rls_dev = true;
 	}
 
 	err = -ENXIO;
 	if (unlikely(dev == NULL))
 		goto out;
-
-	reserve = dev->hard_header_len;
-
 	err = -ENETDOWN;
 	if (unlikely(!(dev->flags & IFF_UP)))
 		goto out_put;
 
+	reserve = dev->hard_header_len;
+
 	size_max = po->tx_ring.frame_size
 		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
 
@@ -2139,12 +2219,13 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
 			}
 		}
 
+		skb_set_queue_mapping(skb, packet_pick_tx_queue(dev));
 		skb->destructor = tpacket_destruct_skb;
 		__packet_set_status(po, ph, TP_STATUS_SENDING);
 		atomic_inc(&po->tx_ring.pending);
 
 		status = TP_STATUS_SEND_REQUEST;
-		err = dev_queue_xmit(skb);
+		err = po->xmit(skb);
 		if (unlikely(err > 0)) {
 			err = net_xmit_errno(err);
 			if (err && __packet_get_status(po, ph) ==
@@ -2173,8 +2254,7 @@ out_status:
 	__packet_set_status(po, ph, status);
 	kfree_skb(skb);
 out_put:
-	if (need_rls_dev)
-		dev_put(dev);
+	dev_put(dev);
 out:
 	mutex_unlock(&po->pg_vec_lock);
 	return err;
@@ -2204,15 +2284,13 @@ static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
 	return skb;
 }
 
-static int packet_snd(struct socket *sock,
-			  struct msghdr *msg, size_t len)
+static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
 {
 	struct sock *sk = sock->sk;
 	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
 	struct sk_buff *skb;
 	struct net_device *dev;
 	__be16 proto;
-	bool need_rls_dev = false;
 	unsigned char *addr;
 	int err, reserve = 0;
 	struct virtio_net_hdr vnet_hdr = { 0 };
@@ -2227,8 +2305,8 @@ static int packet_snd(struct socket *sock,
 	 *	Get and verify the address.
 	 */
 
-	if (saddr == NULL) {
-		dev = po->prot_hook.dev;
+	if (likely(saddr == NULL)) {
+		dev	= packet_cached_dev_get(po);
 		proto	= po->num;
 		addr	= NULL;
 	} else {
@@ -2240,19 +2318,17 @@ static int packet_snd(struct socket *sock,
 		proto	= saddr->sll_protocol;
 		addr	= saddr->sll_addr;
 		dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
-		need_rls_dev = true;
 	}
 
 	err = -ENXIO;
-	if (dev == NULL)
+	if (unlikely(dev == NULL))
 		goto out_unlock;
-	if (sock->type == SOCK_RAW)
-		reserve = dev->hard_header_len;
-
 	err = -ENETDOWN;
-	if (!(dev->flags & IFF_UP))
+	if (unlikely(!(dev->flags & IFF_UP)))
 		goto out_unlock;
 
+	if (sock->type == SOCK_RAW)
+		reserve = dev->hard_header_len;
 	if (po->has_vnet_hdr) {
 		vnet_hdr_len = sizeof(vnet_hdr);
 
@@ -2353,6 +2429,7 @@ static int packet_snd(struct socket *sock,
 	skb->dev = dev;
 	skb->priority = sk->sk_priority;
 	skb->mark = sk->sk_mark;
+	skb_set_queue_mapping(skb, packet_pick_tx_queue(dev));
 
 	if (po->has_vnet_hdr) {
 		if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
@@ -2373,28 +2450,23 @@ static int packet_snd(struct socket *sock,
 		len += vnet_hdr_len;
 	}
 
-	skb_probe_transport_header(skb, reserve);
-
+	if (!packet_use_direct_xmit(po))
+		skb_probe_transport_header(skb, reserve);
 	if (unlikely(extra_len == 4))
 		skb->no_fcs = 1;
 
-	/*
-	 *	Now send it
-	 */
-
-	err = dev_queue_xmit(skb);
+	err = po->xmit(skb);
 	if (err > 0 && (err = net_xmit_errno(err)) != 0)
 		goto out_unlock;
 
-	if (need_rls_dev)
-		dev_put(dev);
+	dev_put(dev);
 
 	return len;
 
 out_free:
 	kfree_skb(skb);
 out_unlock:
-	if (dev && need_rls_dev)
+	if (dev)
 		dev_put(dev);
 out:
 	return err;
@@ -2405,6 +2477,7 @@ static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
 {
 	struct sock *sk = sock->sk;
 	struct packet_sock *po = pkt_sk(sk);
+
 	if (po->tx_ring.pg_vec)
 		return tpacket_snd(po, msg);
 	else
@@ -2439,6 +2512,8 @@ static int packet_release(struct socket *sock)
 
 	spin_lock(&po->bind_lock);
 	unregister_prot_hook(sk, false);
+	packet_cached_dev_reset(po);
+
 	if (po->prot_hook.dev) {
 		dev_put(po->prot_hook.dev);
 		po->prot_hook.dev = NULL;
@@ -2494,14 +2569,17 @@ static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protoc
 
 	spin_lock(&po->bind_lock);
 	unregister_prot_hook(sk, true);
+
 	po->num = protocol;
 	po->prot_hook.type = protocol;
 	if (po->prot_hook.dev)
 		dev_put(po->prot_hook.dev);
-	po->prot_hook.dev = dev;
 
+	po->prot_hook.dev = dev;
 	po->ifindex = dev ? dev->ifindex : 0;
 
+	packet_cached_dev_assign(po, dev);
+
 	if (protocol == 0)
 		goto out_unlock;
 
@@ -2614,6 +2692,9 @@ static int packet_create(struct net *net, struct socket *sock, int protocol,
 	po = pkt_sk(sk);
 	sk->sk_family = PF_PACKET;
 	po->num = proto;
+	po->xmit = dev_queue_xmit;
+
+	packet_cached_dev_reset(po);
 
 	sk->sk_destruct = packet_sock_destruct;
 	sk_refcnt_debug_inc(sk);
@@ -2660,7 +2741,6 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
 	struct sock *sk = sock->sk;
 	struct sk_buff *skb;
 	int copied, err;
-	struct sockaddr_ll *sll;
 	int vnet_hdr_len = 0;
 
 	err = -EINVAL;
@@ -2744,22 +2824,10 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
 			goto out_free;
 	}
 
-	/*
-	 *	If the address length field is there to be filled in, we fill
-	 *	it in now.
-	 */
-
-	sll = &PACKET_SKB_CB(skb)->sa.ll;
-	if (sock->type == SOCK_PACKET)
-		msg->msg_namelen = sizeof(struct sockaddr_pkt);
-	else
-		msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
-
-	/*
-	 *	You lose any data beyond the buffer you gave. If it worries a
-	 *	user program they can ask the device for its MTU anyway.
+	/* You lose any data beyond the buffer you gave. If it worries
+	 * a user program they can ask the device for its MTU
+	 * anyway.
 	 */
-
 	copied = skb->len;
 	if (copied > len) {
 		copied = len;
@@ -2772,9 +2840,20 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
 
 	sock_recv_ts_and_drops(msg, sk, skb);
 
-	if (msg->msg_name)
+	if (msg->msg_name) {
+		/* If the address length field is there to be filled
+		 * in, we fill it in now.
+		 */
+		if (sock->type == SOCK_PACKET) {
+			msg->msg_namelen = sizeof(struct sockaddr_pkt);
+		} else {
+			struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
+			msg->msg_namelen = sll->sll_halen +
+				offsetof(struct sockaddr_ll, sll_addr);
+		}
 		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
 		       msg->msg_namelen);
+	}
 
 	if (pkt_sk(sk)->auxdata) {
 		struct tpacket_auxdata aux;
@@ -3193,6 +3272,18 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
 		po->tp_tx_has_off = !!val;
 		return 0;
 	}
+	case PACKET_QDISC_BYPASS:
+	{
+		int val;
+
+		if (optlen != sizeof(val))
+			return -EINVAL;
+		if (copy_from_user(&val, optval, sizeof(val)))
+			return -EFAULT;
+
+		po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
+		return 0;
+	}
 	default:
 		return -ENOPROTOOPT;
 	}
@@ -3285,6 +3376,9 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
 	case PACKET_TX_HAS_OFF:
 		val = po->tp_tx_has_off;
 		break;
+	case PACKET_QDISC_BYPASS:
+		val = packet_use_direct_xmit(po);
+		break;
 	default:
 		return -ENOPROTOOPT;
 	}
@@ -3326,6 +3420,7 @@ static int packet_notifier(struct notifier_block *this,
 						sk->sk_error_report(sk);
 				}
 				if (msg == NETDEV_UNREGISTER) {
+					packet_cached_dev_reset(po);
 					po->ifindex = -1;
 					if (po->prot_hook.dev)
 						dev_put(po->prot_hook.dev);