1 files changed, 104 insertions, 78 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 23e9eb66197f..85e14adf5207 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -70,6 +70,7 @@
 #include <net/netns/generic.h>
 #include <net/rtnetlink.h>
 #include <net/sock.h>
+#include <net/xdp.h>
 #include <linux/seq_file.h>
 #include <linux/uio.h>
 #include <linux/skb_array.h>
@@ -80,6 +81,9 @@
 #include <linux/uaccess.h>
 #include <linux/proc_fs.h>
 
+static void tun_default_link_ksettings(struct net_device *dev,
+				       struct ethtool_link_ksettings *cmd);
+
 /* Uncomment to enable debugging */
 /* #define TUN_DEBUG 1 */
 
@@ -241,6 +245,7 @@ struct tun_struct {
 	struct bpf_prog __rcu *xdp_prog;
 	struct tun_prog __rcu *steering_prog;
 	struct tun_prog __rcu *filter_prog;
+	struct ethtool_link_ksettings link_ksettings;
 };
 
 struct veth {
@@ -248,11 +253,11 @@ struct veth {
 	__be16 h_vlan_TCI;
 };
 
-bool tun_is_xdp_buff(void *ptr)
+bool tun_is_xdp_frame(void *ptr)
 {
 	return (unsigned long)ptr & TUN_XDP_FLAG;
 }
-EXPORT_SYMBOL(tun_is_xdp_buff);
+EXPORT_SYMBOL(tun_is_xdp_frame);
 
 void *tun_xdp_to_ptr(void *ptr)
 {
@@ -525,11 +530,6 @@ static void tun_flow_update(struct tun_struct *tun, u32 rxhash,
 
 	rcu_read_lock();
 
-	/* We may get a very small possibility of OOO during switching, not
-	 * worth to optimize.*/
-	if (tun->numqueues == 1 || tfile->detached)
-		goto unlock;
-
 	e = tun_flow_find(head, rxhash);
 	if (likely(e)) {
 		/* TODO: keep queueing to old queue until it's empty? */
@@ -548,7 +548,6 @@ static void tun_flow_update(struct tun_struct *tun, u32 rxhash,
 		spin_unlock_bh(&tun->lock);
 	}
 
-unlock:
 	rcu_read_unlock();
 }
 
@@ -660,10 +659,10 @@ void tun_ptr_free(void *ptr)
 {
 	if (!ptr)
 		return;
-	if (tun_is_xdp_buff(ptr)) {
-		struct xdp_buff *xdp = tun_ptr_to_xdp(ptr);
+	if (tun_is_xdp_frame(ptr)) {
+		struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr);
 
-		put_page(virt_to_head_page(xdp->data));
+		xdp_return_frame(xdpf);
 	} else {
 		__skb_array_destroy_skb(ptr);
 	}
@@ -848,6 +847,12 @@ static int tun_attach(struct tun_struct *tun, struct file *file,
 				       tun->dev, tfile->queue_index);
 		if (err < 0)
 			goto out;
+		err = xdp_rxq_info_reg_mem_model(&tfile->xdp_rxq,
+						 MEM_TYPE_PAGE_SHARED, NULL);
+		if (err < 0) {
+			xdp_rxq_info_unreg(&tfile->xdp_rxq);
+			goto out;
+		}
 		err = 0;
 	}
 
@@ -1284,65 +1289,69 @@ static const struct net_device_ops tun_netdev_ops = {
 	.ndo_get_stats64	= tun_net_get_stats64,
 };
 
-static int tun_xdp_xmit(struct net_device *dev, struct xdp_buff *xdp)
+static void __tun_xdp_flush_tfile(struct tun_file *tfile)
+{
+	/* Notify and wake up reader process */
+	if (tfile->flags & TUN_FASYNC)
+		kill_fasync(&tfile->fasync, SIGIO, POLL_IN);
+	tfile->socket.sk->sk_data_ready(tfile->socket.sk);
+}
+
+static int tun_xdp_xmit(struct net_device *dev, int n,
+			struct xdp_frame **frames, u32 flags)
 {
 	struct tun_struct *tun = netdev_priv(dev);
-	struct xdp_buff *buff = xdp->data_hard_start;
-	int headroom = xdp->data - xdp->data_hard_start;
 	struct tun_file *tfile;
 	u32 numqueues;
-	int ret = 0;
-
-	/* Assure headroom is available and buff is properly aligned */
-	if (unlikely(headroom < sizeof(*xdp) || tun_is_xdp_buff(xdp)))
-		return -ENOSPC;
+	int drops = 0;
+	int cnt = n;
+	int i;
 
-	*buff = *xdp;
+	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
+		return -EINVAL;
 
 	rcu_read_lock();
 
 	numqueues = READ_ONCE(tun->numqueues);
 	if (!numqueues) {
-		ret = -ENOSPC;
-		goto out;
+		rcu_read_unlock();
+		return -ENXIO; /* Caller will free/return all frames */
 	}
 
 	tfile = rcu_dereference(tun->tfiles[smp_processor_id() %
 					    numqueues]);
-	/* Encode the XDP flag into lowest bit for consumer to differ
-	 * XDP buffer from sk_buff.
-	 */
-	if (ptr_ring_produce(&tfile->tx_ring, tun_xdp_to_ptr(buff))) {
-		this_cpu_inc(tun->pcpu_stats->tx_dropped);
-		ret = -ENOSPC;
+
+	spin_lock(&tfile->tx_ring.producer_lock);
+	for (i = 0; i < n; i++) {
+		struct xdp_frame *xdp = frames[i];
+		/* Encode the XDP flag into lowest bit for consumer to differ
+		 * XDP buffer from sk_buff.
+		 */
+		void *frame = tun_xdp_to_ptr(xdp);
+
+		if (__ptr_ring_produce(&tfile->tx_ring, frame)) {
+			this_cpu_inc(tun->pcpu_stats->tx_dropped);
+			xdp_return_frame_rx_napi(xdp);
+			drops++;
+		}
 	}
+	spin_unlock(&tfile->tx_ring.producer_lock);
+
+	if (flags & XDP_XMIT_FLUSH)
+		__tun_xdp_flush_tfile(tfile);
 
-out:
 	rcu_read_unlock();
-	return ret;
+	return cnt - drops;
 }
 
-static void tun_xdp_flush(struct net_device *dev)
+static int tun_xdp_tx(struct net_device *dev, struct xdp_buff *xdp)
 {
-	struct tun_struct *tun = netdev_priv(dev);
-	struct tun_file *tfile;
-	u32 numqueues;
+	struct xdp_frame *frame = convert_to_xdp_frame(xdp);
 
-	rcu_read_lock();
+	if (unlikely(!frame))
+		return -EOVERFLOW;
 
-	numqueues = READ_ONCE(tun->numqueues);
-	if (!numqueues)
-		goto out;
-
-	tfile = rcu_dereference(tun->tfiles[smp_processor_id() %
-					    numqueues]);
-	/* Notify and wake up reader process */
-	if (tfile->flags & TUN_FASYNC)
-		kill_fasync(&tfile->fasync, SIGIO, POLL_IN);
-	tfile->socket.sk->sk_data_ready(tfile->socket.sk);
-
-out:
-	rcu_read_unlock();
+	return tun_xdp_xmit(dev, 1, &frame, XDP_XMIT_FLUSH);
 }
 
 static const struct net_device_ops tap_netdev_ops = {
@@ -1363,7 +1372,6 @@ static const struct net_device_ops tap_netdev_ops = {
 	.ndo_get_stats64	= tun_net_get_stats64,
 	.ndo_bpf		= tun_xdp,
 	.ndo_xdp_xmit		= tun_xdp_xmit,
-	.ndo_xdp_flush		= tun_xdp_flush,
 };
 
 static void tun_flow_init(struct tun_struct *tun)
@@ -1680,14 +1688,14 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 		case XDP_TX:
 			get_page(alloc_frag->page);
 			alloc_frag->offset += buflen;
-			if (tun_xdp_xmit(tun->dev, &xdp))
+			if (tun_xdp_tx(tun->dev, &xdp))
 				goto err_redirect;
-			tun_xdp_flush(tun->dev);
 			rcu_read_unlock();
 			local_bh_enable();
 			return NULL;
 		case XDP_PASS:
 			delta = orig_data - xdp.data;
+			len = xdp.data_end - xdp.data;
 			break;
 		default:
 			bpf_warn_invalid_xdp_action(act);
@@ -1708,7 +1716,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 	}
 
 	skb_reserve(skb, pad - delta);
-	skb_put(skb, len + delta);
+	skb_put(skb, len);
 	get_page(alloc_frag->page);
 	alloc_frag->offset += buflen;
 
@@ -1932,10 +1940,13 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 		local_bh_enable();
 	}
 
-	rcu_read_lock();
-	if (!rcu_dereference(tun->steering_prog))
+	/* Compute the costly rx hash only if needed for flow updates.
+	 * We may get a very small possibility of OOO during switching, not
+	 * worth to optimize.
+	 */
+	if (!rcu_access_pointer(tun->steering_prog) && tun->numqueues > 1 &&
+	    !tfile->detached)
 		rxhash = __skb_get_hash_symmetric(skb);
-	rcu_read_unlock();
 
 	if (frags) {
 		/* Exercise flow dissector code path. */
@@ -2004,11 +2015,11 @@ static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
 static ssize_t tun_put_user_xdp(struct tun_struct *tun,
 				struct tun_file *tfile,
-				struct xdp_buff *xdp,
+				struct xdp_frame *xdp_frame,
 				struct iov_iter *iter)
 {
 	int vnet_hdr_sz = 0;
-	size_t size = xdp->data_end - xdp->data;
+	size_t size = xdp_frame->len;
 	struct tun_pcpu_stats *stats;
 	size_t ret;
 
@@ -2024,7 +2035,7 @@ static ssize_t tun_put_user_xdp(struct tun_struct *tun,
 		iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso));
 	}
 
-	ret = copy_to_iter(xdp->data, size, iter) + vnet_hdr_sz;
+	ret = copy_to_iter(xdp_frame->data, size, iter) + vnet_hdr_sz;
 
 	stats = get_cpu_ptr(tun->pcpu_stats);
 	u64_stats_update_begin(&stats->syncp);
@@ -2192,11 +2203,11 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
 			return err;
 	}
 
-	if (tun_is_xdp_buff(ptr)) {
-		struct xdp_buff *xdp = tun_ptr_to_xdp(ptr);
+	if (tun_is_xdp_frame(ptr)) {
+		struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr);
 
-		ret = tun_put_user_xdp(tun, tfile, xdp, to);
-		put_page(virt_to_head_page(xdp->data));
+		ret = tun_put_user_xdp(tun, tfile, xdpf, to);
+		xdp_return_frame(xdpf);
 	} else {
 		struct sk_buff *skb = ptr;
 
@@ -2278,6 +2289,7 @@ static void tun_setup(struct net_device *dev)
 
 	tun->owner = INVALID_UID;
 	tun->group = INVALID_GID;
+	tun_default_link_ksettings(dev, &tun->link_ksettings);
 
 	dev->ethtool_ops = &tun_ethtool_ops;
 	dev->needs_free_netdev = true;
@@ -2435,10 +2447,10 @@ out_free:
 static int tun_ptr_peek_len(void *ptr)
 {
 	if (likely(ptr)) {
-		if (tun_is_xdp_buff(ptr)) {
-			struct xdp_buff *xdp = tun_ptr_to_xdp(ptr);
+		if (tun_is_xdp_frame(ptr)) {
+			struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr);
 
-			return xdp->data_end - xdp->data;
+			return xdpf->len;
 		}
 		return __skb_array_len_with_tag(ptr);
 	} else {
@@ -2852,10 +2864,10 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 			    unsigned long arg, int ifreq_len)
 {
 	struct tun_file *tfile = file->private_data;
+	struct net *net = sock_net(&tfile->sk);
 	struct tun_struct *tun;
 	void __user* argp = (void __user*)arg;
 	struct ifreq ifr;
-	struct net *net;
 	kuid_t owner;
 	kgid_t group;
 	int sndbuf;
@@ -2879,14 +2891,18 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 		 */
 		return put_user(IFF_TUN | IFF_TAP | TUN_FEATURES,
 				(unsigned int __user*)argp);
-	} else if (cmd == TUNSETQUEUE)
+	} else if (cmd == TUNSETQUEUE) {
 		return tun_set_queue(file, &ifr);
+	} else if (cmd == SIOCGSKNS) {
+		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+			return -EPERM;
+		return open_related_ns(&net->ns, get_net_ns);
+	}
 
 	ret = 0;
 	rtnl_lock();
 
 	tun = tun_get(tfile);
-	net = sock_net(&tfile->sk);
 	if (cmd == TUNSETIFF) {
 		ret = -EEXIST;
 		if (tun)
@@ -2916,14 +2932,6 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 		tfile->ifindex = ifindex;
 		goto unlock;
 	}
-	if (cmd == SIOCGSKNS) {
-		ret = -EPERM;
-		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
-			goto unlock;
-
-		ret = open_related_ns(&net->ns, get_net_ns);
-		goto unlock;
-	}
 
 	ret = -EBADFD;
 	if (!tun)
@@ -3313,8 +3321,8 @@ static struct miscdevice tun_miscdev = {
 
 /* ethtool interface */
 
-static int tun_get_link_ksettings(struct net_device *dev,
-				  struct ethtool_link_ksettings *cmd)
+static void tun_default_link_ksettings(struct net_device *dev,
+				       struct ethtool_link_ksettings *cmd)
 {
 	ethtool_link_ksettings_zero_link_mode(cmd, supported);
 	ethtool_link_ksettings_zero_link_mode(cmd, advertising);
@@ -3323,6 +3331,23 @@ static int tun_get_link_ksettings(struct net_device *dev,
 	cmd->base.port		= PORT_TP;
 	cmd->base.phy_address	= 0;
 	cmd->base.autoneg	= AUTONEG_DISABLE;
+}
+
+static int tun_get_link_ksettings(struct net_device *dev,
+				  struct ethtool_link_ksettings *cmd)
+{
+	struct tun_struct *tun = netdev_priv(dev);
+
+	memcpy(cmd, &tun->link_ksettings, sizeof(*cmd));
+	return 0;
+}
+
+static int tun_set_link_ksettings(struct net_device *dev,
+				  const struct ethtool_link_ksettings *cmd)
+{
+	struct tun_struct *tun = netdev_priv(dev);
+
+	memcpy(&tun->link_ksettings, cmd, sizeof(*cmd));
 	return 0;
 }
 
@@ -3393,6 +3418,7 @@ static const struct ethtool_ops tun_ethtool_ops = {
 	.get_coalesce   = tun_get_coalesce,
 	.set_coalesce   = tun_set_coalesce,
 	.get_link_ksettings = tun_get_link_ksettings,
+	.set_link_ksettings = tun_set_link_ksettings,
 };
 
 static int tun_queue_resize(struct tun_struct *tun)