diff options
Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r-- | drivers/net/tun.c | 806 |
1 files changed, 678 insertions, 128 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 42bb820a56c9..7433bb2e4451 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -75,6 +75,7 @@ #include <linux/skb_array.h> #include <linux/bpf.h> #include <linux/bpf_trace.h> +#include <linux/mutex.h> #include <linux/uaccess.h> @@ -121,7 +122,8 @@ do { \ #define TUN_VNET_BE 0x40000000 #define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \ - IFF_MULTI_QUEUE) + IFF_MULTI_QUEUE | IFF_NAPI | IFF_NAPI_FRAGS) + #define GOODCOPY_LEN 128 #define FLT_EXACT_COUNT 8 @@ -172,9 +174,13 @@ struct tun_file { u16 queue_index; unsigned int ifindex; }; + struct napi_struct napi; + bool napi_enabled; + struct mutex napi_mutex; /* Protects access to the above napi */ struct list_head next; struct tun_struct *detached; - struct skb_array tx_array; + struct ptr_ring tx_ring; + struct xdp_rxq_info xdp_rxq; }; struct tun_flow_entry { @@ -190,6 +196,11 @@ struct tun_flow_entry { #define TUN_NUM_FLOW_ENTRIES 1024 +struct tun_prog { + struct rcu_head rcu; + struct bpf_prog *prog; +}; + /* 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. @@ -227,8 +238,102 @@ struct tun_struct { u32 rx_batched; struct tun_pcpu_stats __percpu *pcpu_stats; struct bpf_prog __rcu *xdp_prog; + struct tun_prog __rcu *steering_prog; + struct tun_prog __rcu *filter_prog; +}; + +struct veth { + __be16 h_vlan_proto; + __be16 h_vlan_TCI; }; +bool tun_is_xdp_buff(void *ptr) +{ + return (unsigned long)ptr & TUN_XDP_FLAG; +} +EXPORT_SYMBOL(tun_is_xdp_buff); + +void *tun_xdp_to_ptr(void *ptr) +{ + return (void *)((unsigned long)ptr | TUN_XDP_FLAG); +} +EXPORT_SYMBOL(tun_xdp_to_ptr); + +void *tun_ptr_to_xdp(void *ptr) +{ + return (void *)((unsigned long)ptr & ~TUN_XDP_FLAG); +} +EXPORT_SYMBOL(tun_ptr_to_xdp); + +static int tun_napi_receive(struct napi_struct *napi, int budget) +{ + struct tun_file *tfile = container_of(napi, struct tun_file, napi); + struct sk_buff_head *queue = &tfile->sk.sk_write_queue; + struct sk_buff_head process_queue; + struct sk_buff *skb; + int received = 0; + + __skb_queue_head_init(&process_queue); + + spin_lock(&queue->lock); + skb_queue_splice_tail_init(queue, &process_queue); + spin_unlock(&queue->lock); + + while (received < budget && (skb = __skb_dequeue(&process_queue))) { + napi_gro_receive(napi, skb); + ++received; + } + + if (!skb_queue_empty(&process_queue)) { + spin_lock(&queue->lock); + skb_queue_splice(&process_queue, queue); + spin_unlock(&queue->lock); + } + + return received; +} + +static int tun_napi_poll(struct napi_struct *napi, int budget) +{ + unsigned int received; + + received = tun_napi_receive(napi, budget); + + if (received < budget) + napi_complete_done(napi, received); + + return received; +} + +static void tun_napi_init(struct tun_struct *tun, struct tun_file *tfile, + bool napi_en) +{ + tfile->napi_enabled = napi_en; + 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) +{ + if (tfile->napi_enabled) + napi_disable(&tfile->napi); +} + +static void tun_napi_del(struct tun_struct *tun, struct tun_file *tfile) +{ + if (tfile->napi_enabled) + netif_napi_del(&tfile->napi); +} + +static bool tun_napi_frags_enabled(const struct tun_struct *tun) +{ + return READ_ONCE(tun->flags) & IFF_NAPI_FRAGS; +} + #ifdef CONFIG_TUN_VNET_CROSS_LE static inline bool tun_legacy_is_little_endian(struct tun_struct *tun) { @@ -370,9 +475,9 @@ static void tun_flow_delete_by_queue(struct tun_struct *tun, u16 queue_index) spin_unlock_bh(&tun->lock); } -static void tun_flow_cleanup(unsigned long data) +static void tun_flow_cleanup(struct timer_list *t) { - struct tun_struct *tun = (struct tun_struct *)data; + struct tun_struct *tun = from_timer(tun, t, flow_gc_timer); unsigned long delay = tun->ageing_time; unsigned long next_timer = jiffies + delay; unsigned long count = 0; @@ -380,25 +485,28 @@ static void tun_flow_cleanup(unsigned long data) tun_debug(KERN_INFO, tun, "tun_flow_cleanup\n"); - spin_lock_bh(&tun->lock); + spin_lock(&tun->lock); for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { struct tun_flow_entry *e; struct hlist_node *n; hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) { unsigned long this_timer; - count++; + this_timer = e->updated + delay; - if (time_before_eq(this_timer, jiffies)) + if (time_before_eq(this_timer, jiffies)) { tun_flow_delete(tun, e); - else if (time_before(this_timer, next_timer)) + continue; + } + count++; + if (time_before(this_timer, next_timer)) next_timer = this_timer; } } if (count) mod_timer(&tun->flow_gc_timer, round_jiffies_up(next_timer)); - spin_unlock_bh(&tun->lock); + spin_unlock(&tun->lock); } static void tun_flow_update(struct tun_struct *tun, u32 rxhash, @@ -460,16 +568,13 @@ static inline void tun_flow_save_rps_rxhash(struct tun_flow_entry *e, u32 hash) * 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, - void *accel_priv, select_queue_fallback_t fallback) +static u16 tun_automq_select_queue(struct tun_struct *tun, 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 = ACCESS_ONCE(tun->numqueues); + numqueues = READ_ONCE(tun->numqueues); txq = __skb_get_hash_symmetric(skb); if (txq) { @@ -486,10 +591,37 @@ static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb, txq -= numqueues; } - rcu_read_unlock(); return txq; } +static u16 tun_ebpf_select_queue(struct tun_struct *tun, struct sk_buff *skb) +{ + struct tun_prog *prog; + u16 ret = 0; + + prog = rcu_dereference(tun->steering_prog); + if (prog) + ret = bpf_prog_run_clear_cb(prog->prog, skb); + + return ret % tun->numqueues; +} + +static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb, + void *accel_priv, select_queue_fallback_t fallback) +{ + struct tun_struct *tun = netdev_priv(dev); + u16 ret; + + rcu_read_lock(); + if (rcu_dereference(tun->steering_prog)) + ret = tun_ebpf_select_queue(tun, skb); + else + ret = tun_automq_select_queue(tun, skb); + rcu_read_unlock(); + + return ret; +} + static inline bool tun_not_capable(struct tun_struct *tun) { const struct cred *cred = current_cred(); @@ -523,17 +655,39 @@ static struct tun_struct *tun_enable_queue(struct tun_file *tfile) return tun; } +static void tun_ptr_free(void *ptr) +{ + if (!ptr) + return; + if (tun_is_xdp_buff(ptr)) { + struct xdp_buff *xdp = tun_ptr_to_xdp(ptr); + + put_page(virt_to_head_page(xdp->data)); + } else { + __skb_array_destroy_skb(ptr); + } +} + static void tun_queue_purge(struct tun_file *tfile) { - struct sk_buff *skb; + void *ptr; - while ((skb = skb_array_consume(&tfile->tx_array)) != NULL) - kfree_skb(skb); + while ((ptr = ptr_ring_consume(&tfile->tx_ring)) != NULL) + tun_ptr_free(ptr); skb_queue_purge(&tfile->sk.sk_write_queue); skb_queue_purge(&tfile->sk.sk_error_queue); } +static void tun_cleanup_tx_ring(struct tun_file *tfile) +{ + if (tfile->tx_ring.queue) { + ptr_ring_cleanup(&tfile->tx_ring, tun_ptr_free); + xdp_rxq_info_unreg(&tfile->xdp_rxq); + memset(&tfile->tx_ring, 0, sizeof(tfile->tx_ring)); + } +} + static void __tun_detach(struct tun_file *tfile, bool clean) { struct tun_file *ntfile; @@ -541,6 +695,11 @@ 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); + } + if (tun && !tfile->detached) { u16 index = tfile->queue_index; BUG_ON(index >= tun->numqueues); @@ -575,8 +734,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) tun->dev->reg_state == NETREG_REGISTERED) unregister_netdevice(tun->dev); } - if (tun) - skb_array_cleanup(&tfile->tx_array); + tun_cleanup_tx_ring(tfile); sock_put(&tfile->sk); } } @@ -591,13 +749,13 @@ static void tun_detach(struct tun_file *tfile, bool clean) static void tun_detach_all(struct net_device *dev) { struct tun_struct *tun = netdev_priv(dev); - struct bpf_prog *xdp_prog = rtnl_dereference(tun->xdp_prog); struct tun_file *tfile, *tmp; int i, n = tun->numqueues; for (i = 0; i < n; i++) { tfile = rtnl_dereference(tun->tfiles[i]); BUG_ON(!tfile); + tun_napi_disable(tun, tfile); tfile->socket.sk->sk_shutdown = RCV_SHUTDOWN; tfile->socket.sk->sk_data_ready(tfile->socket.sk); RCU_INIT_POINTER(tfile->tun, NULL); @@ -613,25 +771,26 @@ 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); /* Drop read queue */ tun_queue_purge(tfile); sock_put(&tfile->sk); + tun_cleanup_tx_ring(tfile); } list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) { tun_enable_queue(tfile); tun_queue_purge(tfile); sock_put(&tfile->sk); + tun_cleanup_tx_ring(tfile); } BUG_ON(tun->numdisabled != 0); - if (xdp_prog) - bpf_prog_put(xdp_prog); - if (tun->flags & IFF_PERSIST) module_put(THIS_MODULE); } -static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filter) +static int tun_attach(struct tun_struct *tun, struct file *file, + bool skip_filter, bool napi) { struct tun_file *tfile = file->private_data; struct net_device *dev = tun->dev; @@ -666,21 +825,39 @@ static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filte } if (!tfile->detached && - skb_array_init(&tfile->tx_array, dev->tx_queue_len, GFP_KERNEL)) { + ptr_ring_init(&tfile->tx_ring, dev->tx_queue_len, GFP_KERNEL)) { err = -ENOMEM; goto out; } tfile->queue_index = tun->numqueues; tfile->socket.sk->sk_shutdown &= ~RCV_SHUTDOWN; + + if (tfile->detached) { + /* Re-attach detached tfile, updating XDP queue_index */ + WARN_ON(!xdp_rxq_info_is_reg(&tfile->xdp_rxq)); + + if (tfile->xdp_rxq.queue_index != tfile->queue_index) + tfile->xdp_rxq.queue_index = tfile->queue_index; + } else { + /* Setup XDP RX-queue info, for new tfile getting attached */ + err = xdp_rxq_info_reg(&tfile->xdp_rxq, + tun->dev, tfile->queue_index); + if (err < 0) + goto out; + err = 0; + } + rcu_assign_pointer(tfile->tun, tun); rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile); tun->numqueues++; - if (tfile->detached) + if (tfile->detached) { tun_enable_queue(tfile); - else + } else { sock_hold(&tfile->sk); + tun_napi_init(tun, tfile, napi); + } tun_set_real_num_queues(tun); @@ -692,7 +869,7 @@ out: return err; } -static struct tun_struct *__tun_get(struct tun_file *tfile) +static struct tun_struct *tun_get(struct tun_file *tfile) { struct tun_struct *tun; @@ -705,11 +882,6 @@ static struct tun_struct *__tun_get(struct tun_file *tfile) return tun; } -static struct tun_struct *tun_get(struct file *file) -{ - return __tun_get(file->private_data); -} - static void tun_put(struct tun_struct *tun) { dev_put(tun->dev); @@ -855,23 +1027,10 @@ static int tun_net_close(struct net_device *dev) } /* Net device start xmit */ -static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) +static void tun_automq_xmit(struct tun_struct *tun, struct sk_buff *skb) { - struct tun_struct *tun = netdev_priv(dev); - int txq = skb->queue_mapping; - struct tun_file *tfile; - u32 numqueues = 0; - - rcu_read_lock(); - tfile = rcu_dereference(tun->tfiles[txq]); - numqueues = ACCESS_ONCE(tun->numqueues); - - /* Drop packet if interface is not attached */ - if (txq >= numqueues) - goto drop; - #ifdef CONFIG_RPS - if (numqueues == 1 && static_key_false(&rps_needed)) { + if (tun->numqueues == 1 && static_key_false(&rps_needed)) { /* Select queue was not called for the skbuff, so we extract the * RPS hash and save it into the flow_table here. */ @@ -887,6 +1046,37 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) } } #endif +} + +static unsigned int run_ebpf_filter(struct tun_struct *tun, + struct sk_buff *skb, + int len) +{ + struct tun_prog *prog = rcu_dereference(tun->filter_prog); + + if (prog) + len = bpf_prog_run_clear_cb(prog->prog, skb); + + return len; +} + +/* Net device start xmit */ +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; + int len = skb->len; + + rcu_read_lock(); + tfile = rcu_dereference(tun->tfiles[txq]); + + /* Drop packet if interface is not attached */ + if (txq >= tun->numqueues) + goto drop; + + if (!rcu_dereference(tun->steering_prog)) + tun_automq_xmit(tun, skb); tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len); @@ -902,6 +1092,15 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) sk_filter(tfile->socket.sk, skb)) goto drop; + len = run_ebpf_filter(tun, skb, len); + + /* Trim extra bytes since we may insert vlan proto & TCI + * in tun_put_user(). + */ + len -= skb_vlan_tag_present(skb) ? sizeof(struct veth) : 0; + if (len <= 0 || pskb_trim(skb, len)) + goto drop; + if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) goto drop; @@ -914,7 +1113,7 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) nf_reset(skb); - if (skb_array_produce(&tfile->tx_array, skb)) + if (ptr_ring_produce(&tfile->tx_ring, skb)) goto drop; /* Notify and wake up reader process */ @@ -956,13 +1155,33 @@ 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 - * 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. + * 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 @@ -1039,7 +1258,7 @@ static u32 tun_xdp_query(struct net_device *dev) return 0; } -static int tun_xdp(struct net_device *dev, struct netdev_xdp *xdp) +static int tun_xdp(struct net_device *dev, struct netdev_bpf *xdp) { switch (xdp->command) { case XDP_SETUP_PROG: @@ -1067,6 +1286,67 @@ 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) +{ + 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; + + *buff = *xdp; + + rcu_read_lock(); + + numqueues = READ_ONCE(tun->numqueues); + if (!numqueues) { + ret = -ENOSPC; + goto out; + } + + 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; + } + +out: + rcu_read_unlock(); + return ret; +} + +static void tun_xdp_flush(struct net_device *dev) +{ + struct tun_struct *tun = netdev_priv(dev); + struct tun_file *tfile; + u32 numqueues; + + rcu_read_lock(); + + 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(); +} + static const struct net_device_ops tap_netdev_ops = { .ndo_uninit = tun_net_uninit, .ndo_open = tun_net_open, @@ -1083,7 +1363,9 @@ static const struct net_device_ops tap_netdev_ops = { .ndo_features_check = passthru_features_check, .ndo_set_rx_headroom = tun_set_headroom, .ndo_get_stats64 = tun_net_get_stats64, - .ndo_xdp = tun_xdp, + .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) @@ -1094,7 +1376,7 @@ static void tun_flow_init(struct tun_struct *tun) INIT_HLIST_HEAD(&tun->flows[i]); tun->ageing_time = TUN_FLOW_EXPIRE; - setup_timer(&tun->flow_gc_timer, tun_flow_cleanup, (unsigned long)tun); + timer_setup(&tun->flow_gc_timer, tun_flow_cleanup, 0); mod_timer(&tun->flow_gc_timer, round_jiffies_up(jiffies + tun->ageing_time)); } @@ -1146,15 +1428,15 @@ 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 __poll_t tun_chr_poll(struct file *file, poll_table *wait) { struct tun_file *tfile = file->private_data; - struct tun_struct *tun = __tun_get(tfile); + struct tun_struct *tun = tun_get(tfile); struct sock *sk; - unsigned int mask = 0; + __poll_t mask = 0; if (!tun) - return POLLERR; + return EPOLLERR; sk = tfile->socket.sk; @@ -1162,22 +1444,76 @@ static unsigned int tun_chr_poll(struct file *file, poll_table *wait) poll_wait(file, sk_sleep(sk), wait); - if (!skb_array_empty(&tfile->tx_array)) - mask |= POLLIN | POLLRDNORM; + if (!ptr_ring_empty(&tfile->tx_ring)) + mask |= EPOLLIN | EPOLLRDNORM; if (tun->dev->flags & IFF_UP && (sock_writeable(sk) || (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags) && sock_writeable(sk)))) - mask |= POLLOUT | POLLWRNORM; + mask |= EPOLLOUT | EPOLLWRNORM; if (tun->dev->reg_state != NETREG_REGISTERED) - mask = POLLERR; + mask = EPOLLERR; tun_put(tun); return mask; } +static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile, + size_t len, + const struct iov_iter *it) +{ + struct sk_buff *skb; + size_t linear; + int err; + int i; + + if (it->nr_segs > MAX_SKB_FRAGS + 1) + return ERR_PTR(-ENOMEM); + + local_bh_disable(); + skb = napi_get_frags(&tfile->napi); + local_bh_enable(); + if (!skb) + return ERR_PTR(-ENOMEM); + + linear = iov_iter_single_seg_count(it); + err = __skb_grow(skb, linear); + if (err) + goto free; + + skb->len = len; + skb->data_len = len - linear; + skb->truesize += skb->data_len; + + for (i = 1; i < it->nr_segs; i++) { + struct page_frag *pfrag = ¤t->task_frag; + size_t fragsz = it->iov[i].iov_len; + + if (fragsz == 0 || fragsz > PAGE_SIZE) { + err = -EINVAL; + goto free; + } + + if (!skb_page_frag_refill(fragsz, pfrag, GFP_KERNEL)) { + err = -ENOMEM; + goto free; + } + + skb_fill_page_desc(skb, i - 1, pfrag->page, + pfrag->offset, fragsz); + page_ref_inc(pfrag->page); + pfrag->offset += fragsz; + } + + return skb; +free: + /* frees skb and all frags allocated with napi_alloc_frag() */ + napi_free_frags(&tfile->napi); + return ERR_PTR(err); +} + /* 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_file *tfile, @@ -1306,6 +1642,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, else *skb_xdp = 0; + preempt_disable(); rcu_read_lock(); xdp_prog = rcu_dereference(tun->xdp_prog); if (xdp_prog && !*skb_xdp) { @@ -1315,7 +1652,9 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, xdp.data_hard_start = buf; xdp.data = buf + pad; + xdp_set_data_meta_invalid(&xdp); xdp.data_end = xdp.data + len; + xdp.rxq = &tfile->xdp_rxq; orig_data = xdp.data; act = bpf_prog_run_xdp(xdp_prog, &xdp); @@ -1324,8 +1663,11 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, get_page(alloc_frag->page); alloc_frag->offset += buflen; err = xdp_do_redirect(tun->dev, &xdp, xdp_prog); + xdp_do_flush_map(); if (err) goto err_redirect; + rcu_read_unlock(); + preempt_enable(); return NULL; case XDP_TX: xdp_xmit = true; @@ -1347,6 +1689,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, skb = build_skb(buf, buflen); if (!skb) { rcu_read_unlock(); + preempt_enable(); return ERR_PTR(-ENOMEM); } @@ -1358,11 +1701,13 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, if (xdp_xmit) { skb->dev = tun->dev; generic_xdp_tx(skb, xdp_prog); - rcu_read_lock(); + rcu_read_unlock(); + preempt_enable(); return NULL; } rcu_read_unlock(); + preempt_enable(); return skb; @@ -1370,6 +1715,7 @@ err_redirect: put_page(alloc_frag->page); err_xdp: rcu_read_unlock(); + preempt_enable(); this_cpu_inc(tun->pcpu_stats->rx_dropped); return NULL; } @@ -1389,8 +1735,9 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, int copylen; bool zerocopy = false; int err; - u32 rxhash; + u32 rxhash = 0; int skb_xdp = 1; + bool frags = tun_napi_frags_enabled(tun); if (!(tun->dev->flags & IFF_UP)) return -EIO; @@ -1448,7 +1795,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, zerocopy = true; } - if (tun_can_build_skb(tun, tfile, len, noblock, zerocopy)) { + if (!frags && tun_can_build_skb(tun, tfile, len, noblock, zerocopy)) { /* For the packet that is not easy to be processed * (e.g gso or jumbo packet), we will do it at after * skb was created with generic XDP routine. @@ -1469,10 +1816,24 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, linear = tun16_to_cpu(tun, gso.hdr_len); } - skb = tun_alloc_skb(tfile, align, copylen, linear, noblock); + if (frags) { + mutex_lock(&tfile->napi_mutex); + skb = tun_napi_alloc_frags(tfile, copylen, from); + /* tun_napi_alloc_frags() enforces a layout for the skb. + * If zerocopy is enabled, then this layout will be + * overwritten by zerocopy_sg_from_iter(). + */ + zerocopy = false; + } else { + skb = tun_alloc_skb(tfile, align, copylen, linear, + noblock); + } + if (IS_ERR(skb)) { if (PTR_ERR(skb) != -EAGAIN) this_cpu_inc(tun->pcpu_stats->rx_dropped); + if (frags) + mutex_unlock(&tfile->napi_mutex); return PTR_ERR(skb); } @@ -1484,6 +1845,11 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (err) { this_cpu_inc(tun->pcpu_stats->rx_dropped); kfree_skb(skb); + if (frags) { + tfile->napi.skb = NULL; + mutex_unlock(&tfile->napi_mutex); + } + return -EFAULT; } } @@ -1491,6 +1857,11 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (virtio_net_hdr_to_skb(skb, &gso, tun_is_little_endian(tun))) { this_cpu_inc(tun->pcpu_stats->rx_frame_errors); kfree_skb(skb); + if (frags) { + tfile->napi.skb = NULL; + mutex_unlock(&tfile->napi_mutex); + } + return -EINVAL; } @@ -1518,7 +1889,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, skb->dev = tun->dev; break; case IFF_TAP: - skb->protocol = eth_type_trans(skb, tun->dev); + if (!frags) + skb->protocol = eth_type_trans(skb, tun->dev); break; } @@ -1551,12 +1923,45 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, rcu_read_unlock(); } - rxhash = __skb_get_hash_symmetric(skb); -#ifndef CONFIG_4KSTACKS - tun_rx_batched(tun, tfile, skb, more); -#else - netif_rx_ni(skb); -#endif + rcu_read_lock(); + if (!rcu_dereference(tun->steering_prog)) + rxhash = __skb_get_hash_symmetric(skb); + rcu_read_unlock(); + + if (frags) { + /* Exercise flow dissector code path. */ + u32 headlen = eth_get_headlen(skb->data, skb_headlen(skb)); + + if (unlikely(headlen > skb_headlen(skb))) { + this_cpu_inc(tun->pcpu_stats->rx_dropped); + napi_free_frags(&tfile->napi); + mutex_unlock(&tfile->napi_mutex); + WARN_ON(1); + return -ENOMEM; + } + + local_bh_disable(); + napi_gro_frags(&tfile->napi); + local_bh_enable(); + mutex_unlock(&tfile->napi_mutex); + } else if (tfile->napi_enabled) { + struct sk_buff_head *queue = &tfile->sk.sk_write_queue; + int queue_len; + + spin_lock_bh(&queue->lock); + __skb_queue_tail(queue, skb); + queue_len = skb_queue_len(queue); + spin_unlock(&queue->lock); + + if (!more || queue_len > NAPI_POLL_WEIGHT) + napi_schedule(&tfile->napi); + + local_bh_enable(); + } else if (!IS_ENABLED(CONFIG_4KSTACKS)) { + tun_rx_batched(tun, tfile, skb, more); + } else { + netif_rx_ni(skb); + } stats = get_cpu_ptr(tun->pcpu_stats); u64_stats_update_begin(&stats->syncp); @@ -1565,15 +1970,17 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, u64_stats_update_end(&stats->syncp); put_cpu_ptr(stats); - tun_flow_update(tun, rxhash, tfile); + if (rxhash) + tun_flow_update(tun, rxhash, tfile); + return total_len; } static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; - struct tun_struct *tun = tun_get(file); struct tun_file *tfile = file->private_data; + struct tun_struct *tun = tun_get(tfile); ssize_t result; if (!tun) @@ -1586,6 +1993,40 @@ static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) return result; } +static ssize_t tun_put_user_xdp(struct tun_struct *tun, + struct tun_file *tfile, + struct xdp_buff *xdp, + struct iov_iter *iter) +{ + int vnet_hdr_sz = 0; + size_t size = xdp->data_end - xdp->data; + struct tun_pcpu_stats *stats; + size_t ret; + + if (tun->flags & IFF_VNET_HDR) { + struct virtio_net_hdr gso = { 0 }; + + vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz); + if (unlikely(iov_iter_count(iter) < vnet_hdr_sz)) + return -EINVAL; + if (unlikely(copy_to_iter(&gso, sizeof(gso), iter) != + sizeof(gso))) + return -EFAULT; + iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso)); + } + + ret = copy_to_iter(xdp->data, size, iter) + vnet_hdr_sz; + + stats = get_cpu_ptr(tun->pcpu_stats); + u64_stats_update_begin(&stats->syncp); + stats->tx_packets++; + stats->tx_bytes += ret; + u64_stats_update_end(&stats->syncp); + put_cpu_ptr(tun->pcpu_stats); + + return ret; +} + /* Put packet to the user space buffer */ static ssize_t tun_put_user(struct tun_struct *tun, struct tun_file *tfile, @@ -1650,10 +2091,7 @@ static ssize_t tun_put_user(struct tun_struct *tun, if (vlan_hlen) { int ret; - struct { - __be16 h_vlan_proto; - __be16 h_vlan_TCI; - } veth; + struct veth veth; veth.h_vlan_proto = skb->vlan_proto; veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb)); @@ -1683,15 +2121,14 @@ done: return total; } -static struct sk_buff *tun_ring_recv(struct tun_file *tfile, int noblock, - int *err) +static void *tun_ring_recv(struct tun_file *tfile, int noblock, int *err) { DECLARE_WAITQUEUE(wait, current); - struct sk_buff *skb = NULL; + void *ptr = NULL; int error = 0; - skb = skb_array_consume(&tfile->tx_array); - if (skb) + ptr = ptr_ring_consume(&tfile->tx_ring); + if (ptr) goto out; if (noblock) { error = -EAGAIN; @@ -1702,8 +2139,8 @@ static struct sk_buff *tun_ring_recv(struct tun_file *tfile, int noblock, current->state = TASK_INTERRUPTIBLE; while (1) { - skb = skb_array_consume(&tfile->tx_array); - if (skb) + ptr = ptr_ring_consume(&tfile->tx_ring); + if (ptr) break; if (signal_pending(current)) { error = -ERESTARTSYS; @@ -1722,33 +2159,44 @@ static struct sk_buff *tun_ring_recv(struct tun_file *tfile, int noblock, out: *err = error; - return skb; + return ptr; } static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, struct iov_iter *to, - int noblock, struct sk_buff *skb) + int noblock, void *ptr) { ssize_t ret; int err; tun_debug(KERN_INFO, tun, "tun_do_read\n"); - if (!iov_iter_count(to)) + if (!iov_iter_count(to)) { + tun_ptr_free(ptr); return 0; + } - if (!skb) { + if (!ptr) { /* Read frames from ring */ - skb = tun_ring_recv(tfile, noblock, &err); - if (!skb) + ptr = tun_ring_recv(tfile, noblock, &err); + if (!ptr) return err; } - ret = tun_put_user(tun, tfile, skb, to); - if (unlikely(ret < 0)) - kfree_skb(skb); - else - consume_skb(skb); + if (tun_is_xdp_buff(ptr)) { + struct xdp_buff *xdp = tun_ptr_to_xdp(ptr); + + ret = tun_put_user_xdp(tun, tfile, xdp, to); + put_page(virt_to_head_page(xdp->data)); + } else { + struct sk_buff *skb = ptr; + + ret = tun_put_user(tun, tfile, skb, to); + if (unlikely(ret < 0)) + kfree_skb(skb); + else + consume_skb(skb); + } return ret; } @@ -1757,7 +2205,7 @@ static ssize_t tun_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) { struct file *file = iocb->ki_filp; struct tun_file *tfile = file->private_data; - struct tun_struct *tun = __tun_get(tfile); + struct tun_struct *tun = tun_get(tfile); ssize_t len = iov_iter_count(to), ret; if (!tun) @@ -1770,6 +2218,39 @@ static ssize_t tun_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) return ret; } +static void tun_prog_free(struct rcu_head *rcu) +{ + struct tun_prog *prog = container_of(rcu, struct tun_prog, rcu); + + bpf_prog_destroy(prog->prog); + kfree(prog); +} + +static int __tun_set_ebpf(struct tun_struct *tun, + struct tun_prog __rcu **prog_p, + struct bpf_prog *prog) +{ + struct tun_prog *old, *new = NULL; + + if (prog) { + new = kmalloc(sizeof(*new), GFP_KERNEL); + if (!new) + return -ENOMEM; + new->prog = prog; + } + + spin_lock_bh(&tun->lock); + old = rcu_dereference_protected(*prog_p, + lockdep_is_held(&tun->lock)); + rcu_assign_pointer(*prog_p, new); + spin_unlock_bh(&tun->lock); + + if (old) + call_rcu(&old->rcu, tun_prog_free); + + return 0; +} + static void tun_free_netdev(struct net_device *dev) { struct tun_struct *tun = netdev_priv(dev); @@ -1778,6 +2259,8 @@ static void tun_free_netdev(struct net_device *dev) free_percpu(tun->pcpu_stats); tun_flow_uninit(tun); security_tun_dev_free_security(tun->security); + __tun_set_ebpf(tun, &tun->steering_prog, NULL); + __tun_set_ebpf(tun, &tun->filter_prog, NULL); } static void tun_setup(struct net_device *dev) @@ -1823,8 +2306,8 @@ static void tun_sock_write_space(struct sock *sk) wqueue = sk_sleep(sk); if (wqueue && waitqueue_active(wqueue)) - wake_up_interruptible_sync_poll(wqueue, POLLOUT | - POLLWRNORM | POLLWRBAND); + wake_up_interruptible_sync_poll(wqueue, EPOLLOUT | + EPOLLWRNORM | EPOLLWRBAND); tfile = container_of(sk, struct tun_file, sk); kill_fasync(&tfile->fasync, SIGIO, POLL_OUT); @@ -1834,7 +2317,7 @@ static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) { int ret; struct tun_file *tfile = container_of(sock, struct tun_file, socket); - struct tun_struct *tun = __tun_get(tfile); + struct tun_struct *tun = tun_get(tfile); if (!tun) return -EBADFD; @@ -1850,23 +2333,25 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, int flags) { struct tun_file *tfile = container_of(sock, struct tun_file, socket); - struct tun_struct *tun = __tun_get(tfile); + struct tun_struct *tun = tun_get(tfile); + void *ptr = m->msg_control; int ret; - if (!tun) - return -EBADFD; + if (!tun) { + ret = -EBADFD; + goto out_free; + } if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) { ret = -EINVAL; - goto out; + goto out_put_tun; } if (flags & MSG_ERRQUEUE) { ret = sock_recv_errqueue(sock->sk, m, total_len, SOL_PACKET, TUN_TX_TIMESTAMP); goto out; } - ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT, - m->msg_control); + ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT, ptr); if (ret > (ssize_t)total_len) { m->msg_flags |= MSG_TRUNC; ret = flags & MSG_TRUNC ? ret : total_len; @@ -1874,6 +2359,26 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, out: tun_put(tun); return ret; + +out_put_tun: + tun_put(tun); +out_free: + tun_ptr_free(ptr); + return ret; +} + +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); + + return xdp->data_end - xdp->data; + } + return __skb_array_len_with_tag(ptr); + } else { + return 0; + } } static int tun_peek_len(struct socket *sock) @@ -1882,11 +2387,11 @@ static int tun_peek_len(struct socket *sock) struct tun_struct *tun; int ret = 0; - tun = __tun_get(tfile); + tun = tun_get(tfile); if (!tun) return 0; - ret = skb_array_peek_len(&tfile->tx_array); + ret = PTR_RING_PEEK_CALL(&tfile->tx_ring, tun_ptr_peek_len); tun_put(tun); return ret; @@ -1962,6 +2467,15 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (tfile->detached) return -EINVAL; + if ((ifr->ifr_flags & IFF_NAPI_FRAGS)) { + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + if (!(ifr->ifr_flags & IFF_NAPI) || + (ifr->ifr_flags & TUN_TYPE_MASK) != IFF_TAP) + return -EINVAL; + } + dev = __dev_get_by_name(net, ifr->ifr_name); if (dev) { if (ifr->ifr_flags & IFF_TUN_EXCL) @@ -1983,7 +2497,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (err < 0) return err; - err = tun_attach(tun, file, ifr->ifr_flags & IFF_NOFILTER); + err = tun_attach(tun, file, ifr->ifr_flags & IFF_NOFILTER, + ifr->ifr_flags & IFF_NAPI); if (err < 0) return err; @@ -2047,6 +2562,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) tun->filter_attached = false; tun->sndbuf = tfile->socket.sk->sk_sndbuf; tun->rx_batched = 0; + RCU_INIT_POINTER(tun->steering_prog, NULL); tun->pcpu_stats = netdev_alloc_pcpu_stats(struct tun_pcpu_stats); if (!tun->pcpu_stats) { @@ -2072,7 +2588,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) NETIF_F_HW_VLAN_STAG_TX); INIT_LIST_HEAD(&tun->disabled); - err = tun_attach(tun, file, false); + err = tun_attach(tun, file, false, ifr->ifr_flags & IFF_NAPI); if (err < 0) goto err_free_flow; @@ -2144,6 +2660,8 @@ static int set_offload(struct tun_struct *tun, unsigned long arg) features |= NETIF_F_TSO6; arg &= ~(TUN_F_TSO4|TUN_F_TSO6); } + + arg &= ~TUN_F_UFO; } /* This gives the user a way to test for new features in future by @@ -2222,7 +2740,7 @@ 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); + ret = tun_attach(tun, file, false, tun->flags & IFF_NAPI); } else if (ifr->ifr_flags & IFF_DETACH_QUEUE) { tun = rtnl_dereference(tfile->tun); if (!tun || !(tun->flags & IFF_MULTI_QUEUE) || tfile->detached) @@ -2237,6 +2755,26 @@ unlock: return ret; } +static int tun_set_ebpf(struct tun_struct *tun, struct tun_prog **prog_p, + void __user *data) +{ + struct bpf_prog *prog; + int fd; + + if (copy_from_user(&fd, data, sizeof(fd))) + return -EFAULT; + + if (fd == -1) { + prog = NULL; + } else { + prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER); + if (IS_ERR(prog)) + return PTR_ERR(prog); + } + + return __tun_set_ebpf(tun, prog_p, prog); +} + static long __tun_chr_ioctl(struct file *file, unsigned int cmd, unsigned long arg, int ifreq_len) { @@ -2271,7 +2809,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, ret = 0; rtnl_lock(); - tun = __tun_get(tfile); + tun = tun_get(tfile); if (cmd == TUNSETIFF) { ret = -EEXIST; if (tun) @@ -2513,6 +3051,14 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, ret = 0; break; + case TUNSETSTEERINGEBPF: + ret = tun_set_ebpf(tun, &tun->steering_prog, argp); + break; + + case TUNSETFILTEREBPF: + ret = tun_set_ebpf(tun, &tun->filter_prog, argp); + break; + default: ret = -EINVAL; break; @@ -2609,6 +3155,8 @@ static int tun_chr_open(struct inode *inode, struct file * file) sock_set_flag(&tfile->sk, SOCK_ZEROCOPY); + memset(&tfile->tx_ring, 0, sizeof(tfile->tx_ring)); + return 0; } @@ -2622,15 +3170,16 @@ static int tun_chr_close(struct inode *inode, struct file *file) } #ifdef CONFIG_PROC_FS -static void tun_chr_show_fdinfo(struct seq_file *m, struct file *f) +static void tun_chr_show_fdinfo(struct seq_file *m, struct file *file) { + struct tun_file *tfile = file->private_data; struct tun_struct *tun; struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); rtnl_lock(); - tun = tun_get(f); + tun = tun_get(tfile); if (tun) tun_get_iff(current->nsproxy->net_ns, tun, &ifr); rtnl_unlock(); @@ -2755,25 +3304,26 @@ static int tun_queue_resize(struct tun_struct *tun) { struct net_device *dev = tun->dev; struct tun_file *tfile; - struct skb_array **arrays; + struct ptr_ring **rings; int n = tun->numqueues + tun->numdisabled; int ret, i; - arrays = kmalloc_array(n, sizeof(*arrays), GFP_KERNEL); - if (!arrays) + rings = kmalloc_array(n, sizeof(*rings), GFP_KERNEL); + if (!rings) return -ENOMEM; for (i = 0; i < tun->numqueues; i++) { tfile = rtnl_dereference(tun->tfiles[i]); - arrays[i] = &tfile->tx_array; + rings[i] = &tfile->tx_ring; } list_for_each_entry(tfile, &tun->disabled, next) - arrays[i++] = &tfile->tx_array; + rings[i++] = &tfile->tx_ring; - ret = skb_array_resize_multiple(arrays, n, - dev->tx_queue_len, GFP_KERNEL); + ret = ptr_ring_resize_multiple(rings, n, + dev->tx_queue_len, GFP_KERNEL, + tun_ptr_free); - kfree(arrays); + kfree(rings); return ret; } @@ -2859,7 +3409,7 @@ struct socket *tun_get_socket(struct file *file) } EXPORT_SYMBOL_GPL(tun_get_socket); -struct skb_array *tun_get_skb_array(struct file *file) +struct ptr_ring *tun_get_tx_ring(struct file *file) { struct tun_file *tfile; @@ -2868,9 +3418,9 @@ struct skb_array *tun_get_skb_array(struct file *file) tfile = file->private_data; if (!tfile) return ERR_PTR(-EBADFD); - return &tfile->tx_array; + return &tfile->tx_ring; } -EXPORT_SYMBOL_GPL(tun_get_skb_array); +EXPORT_SYMBOL_GPL(tun_get_tx_ring); module_init(tun_init); module_exit(tun_cleanup); |