diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index bdbb526eca7b201fbd9927f14883b179ee03143a..2762c55aeb6692d5adb746b92beb0c160c19f37c 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -109,6 +109,12 @@ struct tap_filter {
unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
};
+/* 1024 is probably a high enough limit: modern hypervisors seem to support on
+ * the order of 100-200 CPUs so this leaves us some breathing space if we want
+ * to match a queue per guest CPU.
+ */
+#define MAX_TAP_QUEUES 1024
+
/* A tun_file connects an open character device to a tuntap netdevice. It
* also contains all socket related strctures (except sock_fprog and tap_filter)
* to serve as one transmit queue for tuntap device. The sock_fprog and
@@ -129,6 +135,7 @@ struct tun_file {
struct fasync_struct *fasync;
/* only used for fasnyc */
unsigned int flags;
+ u16 queue_index;
};
/* Since the socket were moved to tun_file, to preserve the behavior of persist
@@ -136,7 +143,8 @@ struct tun_file {
* file were attached to a persist device.
*/
struct tun_struct {
- struct tun_file __rcu *tfile;
+ struct tun_file __rcu *tfiles[MAX_TAP_QUEUES];
+ unsigned int numqueues;
unsigned int flags;
kuid_t owner;
kgid_t group;
@@ -157,56 +165,157 @@ struct tun_struct {
#endif
};
+/* We try to identify a flow through its rxhash first. The reason that
+ * we do not check rxq no. is becuase some cards(e.g 82599), chooses
+ * the rxq based on the txq where the last packet of the flow comes. As
+ * the userspace application move between processors, we may get a
+ * different rxq no. here. If we could not get rxhash, then we would
+ * hope the rxq no. may help here.
+ */
+static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb)
+{
+ struct tun_struct *tun = netdev_priv(dev);
+ u32 txq = 0;
+ u32 numqueues = 0;
+
+ rcu_read_lock();
+ numqueues = tun->numqueues;
+
+ txq = skb_get_rxhash(skb);
+ if (txq) {
+ /* use multiply and shift instead of expensive divide */
+ txq = ((u64)txq * numqueues) >> 32;
+ } else if (likely(skb_rx_queue_recorded(skb))) {
+ txq = skb_get_rx_queue(skb);
+ while (unlikely(txq >= numqueues))
+ txq -= numqueues;
+ }
+
+ rcu_read_unlock();
+ return txq;
+}
+
+static void tun_set_real_num_queues(struct tun_struct *tun)
+{
+ netif_set_real_num_tx_queues(tun->dev, tun->numqueues);
+ netif_set_real_num_rx_queues(tun->dev, tun->numqueues);
+}
+
+static void __tun_detach(struct tun_file *tfile, bool clean)
+{
+ struct tun_file *ntfile;
+ struct tun_struct *tun;
+ struct net_device *dev;
+
+ tun = rcu_dereference_protected(tfile->tun,
+ lockdep_rtnl_is_held());
+ if (tun) {
+ u16 index = tfile->queue_index;
+ BUG_ON(index >= tun->numqueues);
+ dev = tun->dev;
+
+ rcu_assign_pointer(tun->tfiles[index],
+ tun->tfiles[tun->numqueues - 1]);
+ rcu_assign_pointer(tfile->tun, NULL);
+ ntfile = rcu_dereference_protected(tun->tfiles[index],
+ lockdep_rtnl_is_held());
+ ntfile->queue_index = index;
+
+ --tun->numqueues;
+ sock_put(&tfile->sk);
+
+ synchronize_net();
+ /* Drop read queue */
+ skb_queue_purge(&tfile->sk.sk_receive_queue);
+ tun_set_real_num_queues(tun);
+
+ if (tun->numqueues == 0 && !(tun->flags & TUN_PERSIST))
+ if (dev->reg_state == NETREG_REGISTERED)
+ unregister_netdevice(dev);
+ }
+
+ if (clean) {
+ BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED,
+ &tfile->socket.flags));
+ sk_release_kernel(&tfile->sk);
+ }
+}
+
+static void tun_detach(struct tun_file *tfile, bool clean)
+{
+ rtnl_lock();
+ __tun_detach(tfile, clean);
+ rtnl_unlock();
+}
+
+static void tun_detach_all(struct net_device *dev)
+{
+ struct tun_struct *tun = netdev_priv(dev);
+ struct tun_file *tfile;
+ int i, n = tun->numqueues;
+
+ for (i = 0; i < n; i++) {
+ tfile = rcu_dereference_protected(tun->tfiles[i],
+ lockdep_rtnl_is_held());
+ BUG_ON(!tfile);
+ wake_up_all(&tfile->wq.wait);
+ rcu_assign_pointer(tfile->tun, NULL);
+ --tun->numqueues;
+ }
+ BUG_ON(tun->numqueues != 0);
+
+ synchronize_net();
+ for (i = 0; i < n; i++) {
+ tfile = rcu_dereference_protected(tun->tfiles[i],
+ lockdep_rtnl_is_held());
+ /* Drop read queue */
+ skb_queue_purge(&tfile->sk.sk_receive_queue);
+ sock_put(&tfile->sk);
+ }
+}
+
static int tun_attach(struct tun_struct *tun, struct file *file)
{
struct tun_file *tfile = file->private_data;
int err;
- ASSERT_RTNL();
-
- netif_tx_lock_bh(tun->dev);
-
err = -EINVAL;
- if (tfile->tun)
+ if (rcu_dereference_protected(tfile->tun, lockdep_rtnl_is_held()))
goto out;
err = -EBUSY;
- if (tun->tfile)
+ if (!(tun->flags & TUN_TAP_MQ) && tun->numqueues == 1)
+ goto out;
+
+ err = -E2BIG;
+ if (tun->numqueues == MAX_TAP_QUEUES)
goto out;
err = 0;
- /* Re-attach filter when attaching to a persist device */
+ /* Re-attach the filter to presist device */
if (tun->filter_attached == true) {
err = sk_attach_filter(&tun->fprog, tfile->socket.sk);
if (!err)
goto out;
}
+ tfile->queue_index = tun->numqueues;
rcu_assign_pointer(tfile->tun, tun);
- tfile->socket.sk->sk_sndbuf = tun->sndbuf;
- rcu_assign_pointer(tun->tfile, tfile);
- netif_carrier_on(tun->dev);
+ rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile);
sock_hold(&tfile->sk);
+ tun->numqueues++;
-out:
- netif_tx_unlock_bh(tun->dev);
- return err;
-}
+ tun_set_real_num_queues(tun);
-static void __tun_detach(struct tun_struct *tun)
-{
- struct tun_file *tfile = rcu_dereference_protected(tun->tfile,
- lockdep_rtnl_is_held());
- /* Detach from net device */
- netif_carrier_off(tun->dev);
- rcu_assign_pointer(tun->tfile, NULL);
- if (tfile) {
- rcu_assign_pointer(tfile->tun, NULL);
+ if (tun->numqueues == 1)
+ netif_carrier_on(tun->dev);
- synchronize_net();
- /* Drop read queue */
- skb_queue_purge(&tfile->socket.sk->sk_receive_queue);
- }
+ /* device is allowed to go away first, so no need to hold extra
+ * refcnt.
+ */
+
+out:
+ return err;
}
static struct tun_struct *__tun_get(struct tun_file *tfile)
@@ -349,30 +458,20 @@ static const struct ethtool_ops tun_ethtool_ops;
/* Net device detach from fd. */
static void tun_net_uninit(struct net_device *dev)
{
- struct tun_struct *tun = netdev_priv(dev);
- struct tun_file *tfile = rcu_dereference_protected(tun->tfile,
- lockdep_rtnl_is_held());
-
- /* Inform the methods they need to stop using the dev.
- */
- if (tfile) {
- wake_up_all(&tfile->wq.wait);
- __tun_detach(tun);
- synchronize_net();
- }
+ tun_detach_all(dev);
}
/* Net device open. */
static int tun_net_open(struct net_device *dev)
{
- netif_start_queue(dev);
+ netif_tx_start_all_queues(dev);
return 0;
}
/* Net device close. */
static int tun_net_close(struct net_device *dev)
{
- netif_stop_queue(dev);
+ netif_tx_stop_all_queues(dev);
return 0;
}
@@ -380,16 +479,20 @@ static int tun_net_close(struct net_device *dev)
static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct tun_struct *tun = netdev_priv(dev);
+ int txq = skb->queue_mapping;
struct tun_file *tfile;
rcu_read_lock();
- tfile = rcu_dereference(tun->tfile);
+ tfile = rcu_dereference(tun->tfiles[txq]);
+
/* Drop packet if interface is not attached */
- if (!tfile)
+ if (txq >= tun->numqueues)
goto drop;
tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
+ BUG_ON(!tfile);
+
/* Drop if the filter does not like it.
* This is a noop if the filter is disabled.
* Filter can be enabled only for the TAP devices. */
@@ -400,12 +503,15 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
sk_filter(tfile->socket.sk, skb))
goto drop;
+ /* Limit the number of packets queued by divining txq length with the
+ * number of queues.
+ */
if (skb_queue_len(&tfile->socket.sk->sk_receive_queue)
- >= dev->tx_queue_len) {
+ >= dev->tx_queue_len / tun->numqueues){
if (!(tun->flags & TUN_ONE_QUEUE)) {
/* Normal queueing mode. */
/* Packet scheduler handles dropping of further packets. */
- netif_stop_queue(dev);
+ netif_stop_subqueue(dev, txq);
/* We won't see all dropped packets individually, so overrun
* error is more appropriate. */
@@ -494,6 +600,7 @@ static const struct net_device_ops tun_netdev_ops = {
.ndo_start_xmit = tun_net_xmit,
.ndo_change_mtu = tun_net_change_mtu,
.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
@@ -509,6 +616,7 @@ static const struct net_device_ops tap_netdev_ops = {
.ndo_set_rx_mode = tun_net_mclist,
.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
@@ -550,7 +658,7 @@ static void tun_net_init(struct net_device *dev)
/* Character device part */
/* Poll */
-static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
+static unsigned int tun_chr_poll(struct file *file, poll_table *wait)
{
struct tun_file *tfile = file->private_data;
struct tun_struct *tun = __tun_get(tfile);
@@ -995,7 +1103,7 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
schedule();
continue;
}
- netif_wake_queue(tun->dev);
+ netif_wake_subqueue(tun->dev, tfile->queue_index);
ret = tun_put_user(tun, tfile, skb, iv, len);
kfree_skb(skb);
@@ -1156,6 +1264,9 @@ static int tun_flags(struct tun_struct *tun)
if (tun->flags & TUN_VNET_HDR)
flags |= IFF_VNET_HDR;
+ if (tun->flags & TUN_TAP_MQ)
+ flags |= IFF_MULTI_QUEUE;
+
return flags;
}
@@ -1247,8 +1358,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
if (*ifr->ifr_name)
name = ifr->ifr_name;
- dev = alloc_netdev(sizeof(struct tun_struct), name,
- tun_setup);
+ dev = alloc_netdev_mqs(sizeof(struct tun_struct), name,
+ tun_setup,
+ MAX_TAP_QUEUES, MAX_TAP_QUEUES);
if (!dev)
return -ENOMEM;
@@ -1283,7 +1395,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
err = tun_attach(tun, file);
if (err < 0)
- goto failed;
+ goto err_free_dev;
}
tun_debug(KERN_INFO, tun, "tun_set_iff\n");
@@ -1303,18 +1415,22 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
else
tun->flags &= ~TUN_VNET_HDR;
+ if (ifr->ifr_flags & IFF_MULTI_QUEUE)
+ tun->flags |= TUN_TAP_MQ;
+ else
+ tun->flags &= ~TUN_TAP_MQ;
+
/* Make sure persistent devices do not get stuck in
* xoff state.
*/
if (netif_running(tun->dev))
- netif_wake_queue(tun->dev);
+ netif_tx_wake_all_queues(tun->dev);
strcpy(ifr->ifr_name, tun->dev->name);
return 0;
err_free_dev:
free_netdev(dev);
- failed:
return err;
}
@@ -1369,6 +1485,51 @@ static int set_offload(struct tun_struct *tun, unsigned long arg)
return 0;
}
+static void tun_detach_filter(struct tun_struct *tun, int n)
+{
+ int i;
+ struct tun_file *tfile;
+
+ for (i = 0; i < n; i++) {
+ tfile = rcu_dereference_protected(tun->tfiles[i],
+ lockdep_rtnl_is_held());
+ sk_detach_filter(tfile->socket.sk);
+ }
+
+ tun->filter_attached = false;
+}
+
+static int tun_attach_filter(struct tun_struct *tun)
+{
+ int i, ret = 0;
+ struct tun_file *tfile;
+
+ for (i = 0; i < tun->numqueues; i++) {
+ tfile = rcu_dereference_protected(tun->tfiles[i],
+ lockdep_rtnl_is_held());
+ ret = sk_attach_filter(&tun->fprog, tfile->socket.sk);
+ if (ret) {
+ tun_detach_filter(tun, i);
+ return ret;
+ }
+ }
+
+ tun->filter_attached = true;
+ return ret;
+}
+
+static void tun_set_sndbuf(struct tun_struct *tun)
+{
+ struct tun_file *tfile;
+ int i;
+
+ for (i = 0; i < tun->numqueues; i++) {
+ tfile = rcu_dereference_protected(tun->tfiles[i],
+ lockdep_rtnl_is_held());
+ tfile->socket.sk->sk_sndbuf = tun->sndbuf;
+ }
+}
+
static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
unsigned long arg, int ifreq_len)
{
@@ -1397,6 +1558,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
(unsigned int __user*)argp);
}
+ ret = 0;
rtnl_lock();
tun = __tun_get(tfile);
@@ -1537,7 +1699,8 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
break;
}
- tun->sndbuf = tfile->socket.sk->sk_sndbuf = sndbuf;
+ tun->sndbuf = sndbuf;
+ tun_set_sndbuf(tun);
break;
case TUNGETVNETHDRSZ:
@@ -1568,9 +1731,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
if (copy_from_user(&tun->fprog, argp, sizeof(tun->fprog)))
break;
- ret = sk_attach_filter(&tun->fprog, tfile->socket.sk);
- if (!ret)
- tun->filter_attached = true;
+ ret = tun_attach_filter(tun);
break;
case TUNDETACHFILTER:
@@ -1578,9 +1739,8 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
ret = -EINVAL;
if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
break;
- ret = sk_detach_filter(tfile->socket.sk);
- if (!ret)
- tun->filter_attached = false;
+ ret = 0;
+ tun_detach_filter(tun, tun->numqueues);
break;
default:
@@ -1685,37 +1845,9 @@ static int tun_chr_open(struct inode *inode, struct file * file)
static int tun_chr_close(struct inode *inode, struct file *file)
{
struct tun_file *tfile = file->private_data;
- struct tun_struct *tun;
struct net *net = tfile->net;
- rtnl_lock();
-
- tun = rcu_dereference_protected(tfile->tun, lockdep_rtnl_is_held());
- if (tun) {
- struct net_device *dev = tun->dev;
-
- tun_debug(KERN_INFO, tun, "tun_chr_close\n");
-
- __tun_detach(tun);
-
- synchronize_net();
-
- /* If desirable, unregister the netdevice. */
- if (!(tun->flags & TUN_PERSIST)) {
- if (dev->reg_state == NETREG_REGISTERED)
- unregister_netdevice(dev);
- }
-
- /* drop the reference that netdevice holds */
- sock_put(&tfile->sk);
- }
-
- rtnl_unlock();
-
- /* drop the reference that file holds */
- BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED,
- &tfile->socket.flags));
- sk_release_kernel(&tfile->sk);
+ tun_detach(tfile, true);
put_net(net);
return 0;