diff options
Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r-- | drivers/net/tun.c | 875 |
1 files changed, 640 insertions, 235 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 0873cdcf39be..2ac2164a1e39 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -68,7 +68,6 @@ #include <net/netns/generic.h> #include <net/rtnetlink.h> #include <net/sock.h> -#include <net/cls_cgroup.h> #include <asm/uaccess.h> @@ -110,16 +109,56 @@ 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 + +#define TUN_FLOW_EXPIRE (3 * HZ) + +/* 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 + * tap_filter were kept in tun_struct since they were used for filtering for the + * netdevice not for a specific queue (at least I didn't see the requirement for + * this). + * + * RCU usage: + * The tun_file and tun_struct are loosely coupled, the pointer from one to the + * other can only be read while rcu_read_lock or rtnl_lock is held. + */ struct tun_file { - atomic_t count; - struct tun_struct *tun; + struct sock sk; + struct socket socket; + struct socket_wq wq; + struct tun_struct __rcu *tun; struct net *net; + struct fasync_struct *fasync; + /* only used for fasnyc */ + unsigned int flags; + u16 queue_index; +}; + +struct tun_flow_entry { + struct hlist_node hash_link; + struct rcu_head rcu; + struct tun_struct *tun; + + u32 rxhash; + int queue_index; + unsigned long updated; }; -struct tun_sock; +#define TUN_NUM_FLOW_ENTRIES 1024 +/* Since the socket were moved to tun_file, to preserve the behavior of persist + * device, socket filter, sndbuf and vnet header size were restore when the + * file were attached to a persist device. + */ struct tun_struct { - struct tun_file *tfile; + struct tun_file __rcu *tfiles[MAX_TAP_QUEUES]; + unsigned int numqueues; unsigned int flags; kuid_t owner; kgid_t group; @@ -128,88 +167,349 @@ struct tun_struct { netdev_features_t set_features; #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \ NETIF_F_TSO6|NETIF_F_UFO) - struct fasync_struct *fasync; - - struct tap_filter txflt; - struct socket socket; - struct socket_wq wq; int vnet_hdr_sz; - + int sndbuf; + struct tap_filter txflt; + struct sock_fprog fprog; + /* protected by rtnl lock */ + bool filter_attached; #ifdef TUN_DEBUG int debug; #endif + spinlock_t lock; + struct kmem_cache *flow_cache; + struct hlist_head flows[TUN_NUM_FLOW_ENTRIES]; + struct timer_list flow_gc_timer; + unsigned long ageing_time; }; -struct tun_sock { - struct sock sk; - struct tun_struct *tun; -}; +static inline u32 tun_hashfn(u32 rxhash) +{ + return rxhash & 0x3ff; +} -static inline struct tun_sock *tun_sk(struct sock *sk) +static struct tun_flow_entry *tun_flow_find(struct hlist_head *head, u32 rxhash) { - return container_of(sk, struct tun_sock, sk); + struct tun_flow_entry *e; + struct hlist_node *n; + + hlist_for_each_entry_rcu(e, n, head, hash_link) { + if (e->rxhash == rxhash) + return e; + } + return NULL; } -static int tun_attach(struct tun_struct *tun, struct file *file) +static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun, + struct hlist_head *head, + u32 rxhash, u16 queue_index) { - struct tun_file *tfile = file->private_data; - int err; + struct tun_flow_entry *e = kmem_cache_alloc(tun->flow_cache, + GFP_ATOMIC); + if (e) { + tun_debug(KERN_INFO, tun, "create flow: hash %u index %u\n", + rxhash, queue_index); + e->updated = jiffies; + e->rxhash = rxhash; + e->queue_index = queue_index; + e->tun = tun; + hlist_add_head_rcu(&e->hash_link, head); + } + return e; +} - ASSERT_RTNL(); +static void tun_flow_free(struct rcu_head *head) +{ + struct tun_flow_entry *e + = container_of(head, struct tun_flow_entry, rcu); + kmem_cache_free(e->tun->flow_cache, e); +} - netif_tx_lock_bh(tun->dev); +static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e) +{ + tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n", + e->rxhash, e->queue_index); + hlist_del_rcu(&e->hash_link); + call_rcu(&e->rcu, tun_flow_free); +} - err = -EINVAL; - if (tfile->tun) - goto out; +static void tun_flow_flush(struct tun_struct *tun) +{ + int i; - err = -EBUSY; - if (tun->tfile) - goto out; + spin_lock_bh(&tun->lock); + for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { + struct tun_flow_entry *e; + struct hlist_node *h, *n; - err = 0; - tfile->tun = tun; - tun->tfile = tfile; - tun->socket.file = file; - netif_carrier_on(tun->dev); - dev_hold(tun->dev); - sock_hold(tun->socket.sk); - atomic_inc(&tfile->count); + hlist_for_each_entry_safe(e, h, n, &tun->flows[i], hash_link) + tun_flow_delete(tun, e); + } + spin_unlock_bh(&tun->lock); +} -out: - netif_tx_unlock_bh(tun->dev); - return err; +static void tun_flow_delete_by_queue(struct tun_struct *tun, u16 queue_index) +{ + int i; + + spin_lock_bh(&tun->lock); + for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { + struct tun_flow_entry *e; + struct hlist_node *h, *n; + + hlist_for_each_entry_safe(e, h, n, &tun->flows[i], hash_link) { + if (e->queue_index == queue_index) + tun_flow_delete(tun, e); + } + } + spin_unlock_bh(&tun->lock); } -static void __tun_detach(struct tun_struct *tun) +static void tun_flow_cleanup(unsigned long data) { - /* Detach from net device */ - netif_tx_lock_bh(tun->dev); - netif_carrier_off(tun->dev); - tun->tfile = NULL; - netif_tx_unlock_bh(tun->dev); + struct tun_struct *tun = (struct tun_struct *)data; + unsigned long delay = tun->ageing_time; + unsigned long next_timer = jiffies + delay; + unsigned long count = 0; + int i; - /* Drop read queue */ - skb_queue_purge(&tun->socket.sk->sk_receive_queue); + tun_debug(KERN_INFO, tun, "tun_flow_cleanup\n"); + + spin_lock_bh(&tun->lock); + for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { + struct tun_flow_entry *e; + struct hlist_node *h, *n; + + hlist_for_each_entry_safe(e, h, n, &tun->flows[i], hash_link) { + unsigned long this_timer; + count++; + this_timer = e->updated + delay; + if (time_before_eq(this_timer, jiffies)) + tun_flow_delete(tun, e); + else if (time_before(this_timer, next_timer)) + next_timer = this_timer; + } + } - /* Drop the extra count on the net device */ - dev_put(tun->dev); + if (count) + mod_timer(&tun->flow_gc_timer, round_jiffies_up(next_timer)); + spin_unlock_bh(&tun->lock); } -static void tun_detach(struct tun_struct *tun) +static void tun_flow_update(struct tun_struct *tun, struct sk_buff *skb, + u16 queue_index) +{ + struct hlist_head *head; + struct tun_flow_entry *e; + unsigned long delay = tun->ageing_time; + u32 rxhash = skb_get_rxhash(skb); + + if (!rxhash) + return; + else + head = &tun->flows[tun_hashfn(rxhash)]; + + rcu_read_lock(); + + if (tun->numqueues == 1) + goto unlock; + + e = tun_flow_find(head, rxhash); + if (likely(e)) { + /* TODO: keep queueing to old queue until it's empty? */ + e->queue_index = queue_index; + e->updated = jiffies; + } else { + spin_lock_bh(&tun->lock); + if (!tun_flow_find(head, rxhash)) + tun_flow_create(tun, head, rxhash, queue_index); + + if (!timer_pending(&tun->flow_gc_timer)) + mod_timer(&tun->flow_gc_timer, + round_jiffies_up(jiffies + delay)); + spin_unlock_bh(&tun->lock); + } + +unlock: + rcu_read_unlock(); +} + +/* 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); + struct tun_flow_entry *e; + u32 txq = 0; + u32 numqueues = 0; + + rcu_read_lock(); + numqueues = tun->numqueues; + + txq = skb_get_rxhash(skb); + if (txq) { + e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq); + if (e) + txq = e->queue_index; + else + /* 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 inline bool tun_not_capable(struct tun_struct *tun) +{ + const struct cred *cred = current_cred(); + struct net *net = dev_net(tun->dev); + + return ((uid_valid(tun->owner) && !uid_eq(cred->euid, tun->owner)) || + (gid_valid(tun->group) && !in_egroup_p(tun->group))) && + !ns_capable(net->user_ns, CAP_NET_ADMIN); +} + +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(); + tun_flow_delete_by_queue(tun, tun->numqueues + 1); + /* 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(tun); + __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; + + err = -EINVAL; + if (rcu_dereference_protected(tfile->tun, lockdep_rtnl_is_held())) + goto out; + + err = -EBUSY; + 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 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); + rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile); + sock_hold(&tfile->sk); + tun->numqueues++; + + tun_set_real_num_queues(tun); + + /* 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) { - struct tun_struct *tun = NULL; + struct tun_struct *tun; - if (atomic_inc_not_zero(&tfile->count)) - tun = tfile->tun; + rcu_read_lock(); + tun = rcu_dereference(tfile->tun); + if (tun) + dev_hold(tun->dev); + rcu_read_unlock(); return tun; } @@ -221,10 +521,7 @@ static struct tun_struct *tun_get(struct file *file) static void tun_put(struct tun_struct *tun) { - struct tun_file *tfile = tun->tfile; - - if (atomic_dec_and_test(&tfile->count)) - tun_detach(tfile->tun); + dev_put(tun->dev); } /* TAP filtering */ @@ -344,38 +641,20 @@ 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 = tun->tfile; - - /* Inform the methods they need to stop using the dev. - */ - if (tfile) { - wake_up_all(&tun->wq.wait); - if (atomic_dec_and_test(&tfile->count)) - __tun_detach(tun); - } -} - -static void tun_free_netdev(struct net_device *dev) -{ - struct tun_struct *tun = netdev_priv(dev); - - BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED, &tun->socket.flags)); - - sk_release_kernel(tun->socket.sk); + 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; } @@ -383,38 +662,36 @@ 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; - tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len); + rcu_read_lock(); + tfile = rcu_dereference(tun->tfiles[txq]); /* Drop packet if interface is not attached */ - if (!tun->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. */ if (!check_filter(&tun->txflt, skb)) goto drop; - if (tun->socket.sk->sk_filter && - sk_filter(tun->socket.sk, skb)) + if (tfile->socket.sk->sk_filter && + sk_filter(tfile->socket.sk, skb)) goto drop; - if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) { - if (!(tun->flags & TUN_ONE_QUEUE)) { - /* Normal queueing mode. */ - /* Packet scheduler handles dropping of further packets. */ - netif_stop_queue(dev); - - /* We won't see all dropped packets individually, so overrun - * error is more appropriate. */ - dev->stats.tx_fifo_errors++; - } else { - /* Single queue mode. - * Driver handles dropping of all packets itself. */ - goto drop; - } - } + /* Limit the number of packets queued by dividing txq length with the + * number of queues. + */ + if (skb_queue_len(&tfile->socket.sk->sk_receive_queue) + >= dev->tx_queue_len / tun->numqueues) + goto drop; /* Orphan the skb - required as we might hang on to it * for indefinite time. */ @@ -423,18 +700,22 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) skb_orphan(skb); /* Enqueue packet */ - skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb); + skb_queue_tail(&tfile->socket.sk->sk_receive_queue, skb); /* Notify and wake up reader process */ - if (tun->flags & TUN_FASYNC) - kill_fasync(&tun->fasync, SIGIO, POLL_IN); - wake_up_interruptible_poll(&tun->wq.wait, POLLIN | + if (tfile->flags & TUN_FASYNC) + kill_fasync(&tfile->fasync, SIGIO, POLL_IN); + wake_up_interruptible_poll(&tfile->wq.wait, POLLIN | POLLRDNORM | POLLRDBAND); + + rcu_read_unlock(); return NETDEV_TX_OK; drop: dev->stats.tx_dropped++; + skb_tx_error(skb); kfree_skb(skb); + rcu_read_unlock(); return NETDEV_TX_OK; } @@ -490,6 +771,7 @@ 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 @@ -505,11 +787,43 @@ 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 }; +static int tun_flow_init(struct tun_struct *tun) +{ + int i; + + tun->flow_cache = kmem_cache_create("tun_flow_cache", + sizeof(struct tun_flow_entry), 0, 0, + NULL); + if (!tun->flow_cache) + return -ENOMEM; + + for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) + INIT_HLIST_HEAD(&tun->flows[i]); + + tun->ageing_time = TUN_FLOW_EXPIRE; + setup_timer(&tun->flow_gc_timer, tun_flow_cleanup, (unsigned long)tun); + mod_timer(&tun->flow_gc_timer, + round_jiffies_up(jiffies + tun->ageing_time)); + + return 0; +} + +static void tun_flow_uninit(struct tun_struct *tun) +{ + del_timer_sync(&tun->flow_gc_timer); + tun_flow_flush(tun); + + /* Wait for completion of call_rcu()'s */ + rcu_barrier(); + kmem_cache_destroy(tun->flow_cache); +} + /* Initialize net device. */ static void tun_net_init(struct net_device *dev) { @@ -535,6 +849,7 @@ static void tun_net_init(struct net_device *dev) /* Ethernet TAP Device */ ether_setup(dev); dev->priv_flags &= ~IFF_TX_SKB_SHARING; + dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; eth_hw_addr_random(dev); @@ -546,7 +861,7 @@ 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); @@ -556,11 +871,11 @@ static unsigned int tun_chr_poll(struct file *file, poll_table * wait) if (!tun) return POLLERR; - sk = tun->socket.sk; + sk = tfile->socket.sk; tun_debug(KERN_INFO, tun, "tun_chr_poll\n"); - poll_wait(file, &tun->wq.wait, wait); + poll_wait(file, &tfile->wq.wait, wait); if (!skb_queue_empty(&sk->sk_receive_queue)) mask |= POLLIN | POLLRDNORM; @@ -579,16 +894,14 @@ static unsigned int tun_chr_poll(struct file *file, poll_table * wait) /* prepad is the amount to reserve at front. len is length after that. * linear is a hint as to how much to copy (usually headers). */ -static struct sk_buff *tun_alloc_skb(struct tun_struct *tun, +static struct sk_buff *tun_alloc_skb(struct tun_file *tfile, size_t prepad, size_t len, size_t linear, int noblock) { - struct sock *sk = tun->socket.sk; + struct sock *sk = tfile->socket.sk; struct sk_buff *skb; int err; - sock_update_classid(sk); - /* Under a page? Don't bother with paged skb. */ if (prepad + len < PAGE_SIZE || !linear) linear = len; @@ -685,9 +998,9 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, } /* Get packet from user space buffer */ -static ssize_t tun_get_user(struct tun_struct *tun, void *msg_control, - const struct iovec *iv, size_t total_len, - size_t count, int noblock) +static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, + void *msg_control, const struct iovec *iv, + size_t total_len, size_t count, int noblock) { struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; struct sk_buff *skb; @@ -757,7 +1070,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, void *msg_control, } else copylen = len; - skb = tun_alloc_skb(tun, align, copylen, gso.hdr_len, noblock); + skb = tun_alloc_skb(tfile, align, copylen, gso.hdr_len, noblock); if (IS_ERR(skb)) { if (PTR_ERR(skb) != -EAGAIN) tun->dev->stats.rx_dropped++; @@ -854,6 +1167,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, void *msg_control, tun->dev->stats.rx_packets++; tun->dev->stats.rx_bytes += len; + tun_flow_update(tun, skb, tfile->queue_index); return total_len; } @@ -862,6 +1176,7 @@ static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, { struct file *file = iocb->ki_filp; struct tun_struct *tun = tun_get(file); + struct tun_file *tfile = file->private_data; ssize_t result; if (!tun) @@ -869,8 +1184,8 @@ static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count); - result = tun_get_user(tun, NULL, iv, iov_length(iv, count), count, - file->f_flags & O_NONBLOCK); + result = tun_get_user(tun, tfile, NULL, iv, iov_length(iv, count), + count, file->f_flags & O_NONBLOCK); tun_put(tun); return result; @@ -878,6 +1193,7 @@ static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, /* Put packet to the user space buffer */ static ssize_t tun_put_user(struct tun_struct *tun, + struct tun_file *tfile, struct sk_buff *skb, const struct iovec *iv, int len) { @@ -957,7 +1273,7 @@ static ssize_t tun_put_user(struct tun_struct *tun, return total; } -static ssize_t tun_do_read(struct tun_struct *tun, +static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, struct kiocb *iocb, const struct iovec *iv, ssize_t len, int noblock) { @@ -965,15 +1281,15 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct sk_buff *skb; ssize_t ret = 0; - tun_debug(KERN_INFO, tun, "tun_chr_read\n"); + tun_debug(KERN_INFO, tun, "tun_do_read\n"); if (unlikely(!noblock)) - add_wait_queue(&tun->wq.wait, &wait); + add_wait_queue(&tfile->wq.wait, &wait); while (len) { current->state = TASK_INTERRUPTIBLE; /* Read frames from the queue */ - if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) { + if (!(skb = skb_dequeue(&tfile->socket.sk->sk_receive_queue))) { if (noblock) { ret = -EAGAIN; break; @@ -991,16 +1307,15 @@ static ssize_t tun_do_read(struct tun_struct *tun, schedule(); continue; } - netif_wake_queue(tun->dev); - ret = tun_put_user(tun, skb, iv, len); + ret = tun_put_user(tun, tfile, skb, iv, len); kfree_skb(skb); break; } current->state = TASK_RUNNING; if (unlikely(!noblock)) - remove_wait_queue(&tun->wq.wait, &wait); + remove_wait_queue(&tfile->wq.wait, &wait); return ret; } @@ -1021,13 +1336,22 @@ static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, goto out; } - ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK); + ret = tun_do_read(tun, tfile, iocb, iv, len, + file->f_flags & O_NONBLOCK); ret = min_t(ssize_t, ret, len); out: tun_put(tun); return ret; } +static void tun_free_netdev(struct net_device *dev) +{ + struct tun_struct *tun = netdev_priv(dev); + + tun_flow_uninit(tun); + free_netdev(dev); +} + static void tun_setup(struct net_device *dev) { struct tun_struct *tun = netdev_priv(dev); @@ -1056,7 +1380,7 @@ static struct rtnl_link_ops tun_link_ops __read_mostly = { static void tun_sock_write_space(struct sock *sk) { - struct tun_struct *tun; + struct tun_file *tfile; wait_queue_head_t *wqueue; if (!sock_writeable(sk)) @@ -1070,37 +1394,46 @@ static void tun_sock_write_space(struct sock *sk) wake_up_interruptible_sync_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND); - tun = tun_sk(sk)->tun; - kill_fasync(&tun->fasync, SIGIO, POLL_OUT); -} - -static void tun_sock_destruct(struct sock *sk) -{ - free_netdev(tun_sk(sk)->tun->dev); + tfile = container_of(sk, struct tun_file, sk); + kill_fasync(&tfile->fasync, SIGIO, POLL_OUT); } static int tun_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t total_len) { - struct tun_struct *tun = container_of(sock, struct tun_struct, socket); - return tun_get_user(tun, m->msg_control, m->msg_iov, total_len, - m->msg_iovlen, m->msg_flags & MSG_DONTWAIT); + int ret; + struct tun_file *tfile = container_of(sock, struct tun_file, socket); + struct tun_struct *tun = __tun_get(tfile); + + if (!tun) + return -EBADFD; + ret = tun_get_user(tun, tfile, m->msg_control, m->msg_iov, total_len, + m->msg_iovlen, m->msg_flags & MSG_DONTWAIT); + tun_put(tun); + return ret; } + static int tun_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t total_len, int flags) { - struct tun_struct *tun = container_of(sock, struct tun_struct, socket); + struct tun_file *tfile = container_of(sock, struct tun_file, socket); + struct tun_struct *tun = __tun_get(tfile); int ret; + + if (!tun) + return -EBADFD; + if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) return -EINVAL; - ret = tun_do_read(tun, iocb, m->msg_iov, total_len, + ret = tun_do_read(tun, tfile, iocb, m->msg_iov, total_len, flags & MSG_DONTWAIT); if (ret > total_len) { m->msg_flags |= MSG_TRUNC; ret = flags & MSG_TRUNC ? ret : total_len; } + tun_put(tun); return ret; } @@ -1121,7 +1454,7 @@ static const struct proto_ops tun_socket_ops = { static struct proto tun_proto = { .name = "tun", .owner = THIS_MODULE, - .obj_size = sizeof(struct tun_sock), + .obj_size = sizeof(struct tun_file), }; static int tun_flags(struct tun_struct *tun) @@ -1136,12 +1469,18 @@ static int tun_flags(struct tun_struct *tun) if (tun->flags & TUN_NO_PI) flags |= IFF_NO_PI; + /* This flag has no real effect. We track the value for backwards + * compatibility. + */ if (tun->flags & TUN_ONE_QUEUE) flags |= IFF_ONE_QUEUE; if (tun->flags & TUN_VNET_HDR) flags |= IFF_VNET_HDR; + if (tun->flags & TUN_TAP_MQ) + flags |= IFF_MULTI_QUEUE; + return flags; } @@ -1178,15 +1517,13 @@ static DEVICE_ATTR(group, 0444, tun_show_group, NULL); static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) { - struct sock *sk; struct tun_struct *tun; + struct tun_file *tfile = file->private_data; struct net_device *dev; int err; dev = __dev_get_by_name(net, ifr->ifr_name); if (dev) { - const struct cred *cred = current_cred(); - if (ifr->ifr_flags & IFF_TUN_EXCL) return -EBUSY; if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops) @@ -1196,11 +1533,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) else return -EINVAL; - if (((uid_valid(tun->owner) && !uid_eq(cred->euid, tun->owner)) || - (gid_valid(tun->group) && !in_egroup_p(tun->group))) && - !capable(CAP_NET_ADMIN)) + if (tun_not_capable(tun)) return -EPERM; - err = security_tun_dev_attach(tun->socket.sk); + err = security_tun_dev_attach(tfile->socket.sk); if (err < 0) return err; @@ -1212,7 +1547,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) char *name; unsigned long flags = 0; - if (!capable(CAP_NET_ADMIN)) + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) return -EPERM; err = security_tun_dev_create(); if (err < 0) @@ -1233,8 +1568,9 @@ 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; @@ -1246,46 +1582,38 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) tun->flags = flags; tun->txflt.count = 0; tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr); - set_bit(SOCK_EXTERNALLY_ALLOCATED, &tun->socket.flags); - - err = -ENOMEM; - sk = sk_alloc(&init_net, AF_UNSPEC, GFP_KERNEL, &tun_proto); - if (!sk) - goto err_free_dev; - sk_change_net(sk, net); - tun->socket.wq = &tun->wq; - init_waitqueue_head(&tun->wq.wait); - tun->socket.ops = &tun_socket_ops; - sock_init_data(&tun->socket, sk); - sk->sk_write_space = tun_sock_write_space; - sk->sk_sndbuf = INT_MAX; - sock_set_flag(sk, SOCK_ZEROCOPY); + tun->filter_attached = false; + tun->sndbuf = tfile->socket.sk->sk_sndbuf; - tun_sk(sk)->tun = tun; + spin_lock_init(&tun->lock); - security_tun_dev_post_create(sk); + security_tun_dev_post_create(&tfile->sk); tun_net_init(dev); + err = tun_flow_init(tun); + if (err < 0) + goto err_free_dev; + dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | TUN_USER_FEATURES; dev->features = dev->hw_features; + err = tun_attach(tun, file); + if (err < 0) + goto err_free_dev; + err = register_netdevice(tun->dev); if (err < 0) - goto err_free_sk; + goto err_free_dev; if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) || device_create_file(&tun->dev->dev, &dev_attr_owner) || device_create_file(&tun->dev->dev, &dev_attr_group)) pr_err("Failed to create tun sysfs files\n"); - sk->sk_destruct = tun_sock_destruct; - - err = tun_attach(tun, file); - if (err < 0) - goto failed; + netif_carrier_on(tun->dev); } tun_debug(KERN_INFO, tun, "tun_set_iff\n"); @@ -1295,6 +1623,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) else tun->flags &= ~TUN_NO_PI; + /* This flag has no real effect. We track the value for backwards + * compatibility. + */ if (ifr->ifr_flags & IFF_ONE_QUEUE) tun->flags |= TUN_ONE_QUEUE; else @@ -1305,24 +1636,26 @@ 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_sk: - tun_free_netdev(dev); err_free_dev: free_netdev(dev); - failed: return err; } -static int tun_get_iff(struct net *net, struct tun_struct *tun, +static void tun_get_iff(struct net *net, struct tun_struct *tun, struct ifreq *ifr) { tun_debug(KERN_INFO, tun, "tun_get_iff\n"); @@ -1331,7 +1664,6 @@ static int tun_get_iff(struct net *net, struct tun_struct *tun, ifr->ifr_flags = tun_flags(tun); - return 0; } /* This is like a cut-down ethtool ops, except done via tun fd so no @@ -1373,13 +1705,91 @@ 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 int tun_set_queue(struct file *file, struct ifreq *ifr) +{ + struct tun_file *tfile = file->private_data; + struct tun_struct *tun; + struct net_device *dev; + int ret = 0; + + rtnl_lock(); + + if (ifr->ifr_flags & IFF_ATTACH_QUEUE) { + dev = __dev_get_by_name(tfile->net, ifr->ifr_name); + if (!dev) { + ret = -EINVAL; + goto unlock; + } + + tun = netdev_priv(dev); + if (dev->netdev_ops != &tap_netdev_ops && + dev->netdev_ops != &tun_netdev_ops) + ret = -EINVAL; + else if (tun_not_capable(tun)) + ret = -EPERM; + else + ret = tun_attach(tun, file); + } else if (ifr->ifr_flags & IFF_DETACH_QUEUE) + __tun_detach(tfile, false); + else + ret = -EINVAL; + +unlock: + rtnl_unlock(); + return ret; +} + 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 tun_struct *tun; void __user* argp = (void __user*)arg; - struct sock_fprog fprog; struct ifreq ifr; kuid_t owner; kgid_t group; @@ -1387,7 +1797,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, int vnet_hdr_sz; int ret; - if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89) { + if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) { if (copy_from_user(&ifr, argp, ifreq_len)) return -EFAULT; } else { @@ -1398,10 +1808,12 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, * This is needed because we never checked for invalid flags on * TUNSETIFF. */ return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE | - IFF_VNET_HDR, + IFF_VNET_HDR | IFF_MULTI_QUEUE, (unsigned int __user*)argp); - } + } else if (cmd == TUNSETQUEUE) + return tun_set_queue(file, &ifr); + ret = 0; rtnl_lock(); tun = __tun_get(tfile); @@ -1422,14 +1834,12 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, if (!tun) goto unlock; - tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %d\n", cmd); + tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %u\n", cmd); ret = 0; switch (cmd) { case TUNGETIFF: - ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr); - if (ret) - break; + tun_get_iff(current->nsproxy->net_ns, tun, &ifr); if (copy_to_user(argp, &ifr, ifreq_len)) ret = -EFAULT; @@ -1444,11 +1854,16 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; case TUNSETPERSIST: - /* Disable/Enable persist mode */ - if (arg) + /* Disable/Enable persist mode. Keep an extra reference to the + * module to prevent the module being unprobed. + */ + if (arg) { tun->flags |= TUN_PERSIST; - else + __module_get(THIS_MODULE); + } else { tun->flags &= ~TUN_PERSIST; + module_put(THIS_MODULE); + } tun_debug(KERN_INFO, tun, "persist %s\n", arg ? "enabled" : "disabled"); @@ -1462,7 +1877,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } tun->owner = owner; - tun_debug(KERN_INFO, tun, "owner set to %d\n", + tun_debug(KERN_INFO, tun, "owner set to %u\n", from_kuid(&init_user_ns, tun->owner)); break; @@ -1474,7 +1889,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } tun->group = group; - tun_debug(KERN_INFO, tun, "group set to %d\n", + tun_debug(KERN_INFO, tun, "group set to %u\n", from_kgid(&init_user_ns, tun->group)); break; @@ -1526,7 +1941,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; case TUNGETSNDBUF: - sndbuf = tun->socket.sk->sk_sndbuf; + sndbuf = tfile->socket.sk->sk_sndbuf; if (copy_to_user(argp, &sndbuf, sizeof(sndbuf))) ret = -EFAULT; break; @@ -1537,7 +1952,8 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } - tun->socket.sk->sk_sndbuf = sndbuf; + tun->sndbuf = sndbuf; + tun_set_sndbuf(tun); break; case TUNGETVNETHDRSZ: @@ -1565,10 +1981,10 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) break; ret = -EFAULT; - if (copy_from_user(&fprog, argp, sizeof(fprog))) + if (copy_from_user(&tun->fprog, argp, sizeof(tun->fprog))) break; - ret = sk_attach_filter(&fprog, tun->socket.sk); + ret = tun_attach_filter(tun); break; case TUNDETACHFILTER: @@ -1576,7 +1992,8 @@ 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(tun->socket.sk); + ret = 0; + tun_detach_filter(tun, tun->numqueues); break; default: @@ -1628,27 +2045,21 @@ static long tun_chr_compat_ioctl(struct file *file, static int tun_chr_fasync(int fd, struct file *file, int on) { - struct tun_struct *tun = tun_get(file); + struct tun_file *tfile = file->private_data; int ret; - if (!tun) - return -EBADFD; - - tun_debug(KERN_INFO, tun, "tun_chr_fasync %d\n", on); - - if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0) + if ((ret = fasync_helper(fd, file, on, &tfile->fasync)) < 0) goto out; if (on) { ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0); if (ret) goto out; - tun->flags |= TUN_FASYNC; + tfile->flags |= TUN_FASYNC; } else - tun->flags &= ~TUN_FASYNC; + tfile->flags &= ~TUN_FASYNC; ret = 0; out: - tun_put(tun); return ret; } @@ -1658,44 +2069,39 @@ static int tun_chr_open(struct inode *inode, struct file * file) DBG1(KERN_INFO, "tunX: tun_chr_open\n"); - tfile = kmalloc(sizeof(*tfile), GFP_KERNEL); + tfile = (struct tun_file *)sk_alloc(&init_net, AF_UNSPEC, GFP_KERNEL, + &tun_proto); if (!tfile) return -ENOMEM; - atomic_set(&tfile->count, 0); - tfile->tun = NULL; + rcu_assign_pointer(tfile->tun, NULL); tfile->net = get_net(current->nsproxy->net_ns); + tfile->flags = 0; + + rcu_assign_pointer(tfile->socket.wq, &tfile->wq); + init_waitqueue_head(&tfile->wq.wait); + + tfile->socket.file = file; + tfile->socket.ops = &tun_socket_ops; + + sock_init_data(&tfile->socket, &tfile->sk); + sk_change_net(&tfile->sk, tfile->net); + + tfile->sk.sk_write_space = tun_sock_write_space; + tfile->sk.sk_sndbuf = INT_MAX; + file->private_data = tfile; + set_bit(SOCK_EXTERNALLY_ALLOCATED, &tfile->socket.flags); + return 0; } static int tun_chr_close(struct inode *inode, struct file *file) { struct tun_file *tfile = file->private_data; - struct tun_struct *tun; - - tun = __tun_get(tfile); - if (tun) { - struct net_device *dev = tun->dev; - - tun_debug(KERN_INFO, tun, "tun_chr_close\n"); - - __tun_detach(tun); - - /* If desirable, unregister the netdevice. */ - if (!(tun->flags & TUN_PERSIST)) { - rtnl_lock(); - if (dev->reg_state == NETREG_REGISTERED) - unregister_netdevice(dev); - rtnl_unlock(); - } - } + struct net *net = tfile->net; - tun = tfile->tun; - if (tun) - sock_put(tun->socket.sk); - - put_net(tfile->net); - kfree(tfile); + tun_detach(tfile, true); + put_net(net); return 0; } @@ -1822,14 +2228,13 @@ static void tun_cleanup(void) * holding a reference to the file for as long as the socket is in use. */ struct socket *tun_get_socket(struct file *file) { - struct tun_struct *tun; + struct tun_file *tfile; if (file->f_op != &tun_fops) return ERR_PTR(-EINVAL); - tun = tun_get(file); - if (!tun) + tfile = file->private_data; + if (!tfile) return ERR_PTR(-EBADFD); - tun_put(tun); - return &tun->socket; + return &tfile->socket; } EXPORT_SYMBOL_GPL(tun_get_socket); |