diff options
Diffstat (limited to 'drivers/net/tun.c')
| -rw-r--r-- | drivers/net/tun.c | 211 |
1 files changed, 179 insertions, 32 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index b8e39c6d2a5f..2fba3be5719e 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -241,6 +241,24 @@ struct tun_struct { struct tun_steering_prog __rcu *steering_prog; }; +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); @@ -631,12 +649,25 @@ 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 = ptr_ring_consume(&tfile->tx_ring)) != 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); @@ -689,8 +720,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) unregister_netdevice(tun->dev); } if (tun) { - ptr_ring_cleanup(&tfile->tx_ring, - __skb_array_destroy_skb); + ptr_ring_cleanup(&tfile->tx_ring, tun_ptr_free); xdp_rxq_info_unreg(&tfile->xdp_rxq); } sock_put(&tfile->sk); @@ -1222,6 +1252,67 @@ 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, @@ -1239,6 +1330,8 @@ static const struct net_device_ops tap_netdev_ops = { .ndo_set_rx_headroom = tun_set_headroom, .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) @@ -1863,6 +1956,40 @@ 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, @@ -1960,15 +2087,14 @@ 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 = ptr_ring_consume(&tfile->tx_ring); - if (skb) + ptr = ptr_ring_consume(&tfile->tx_ring); + if (ptr) goto out; if (noblock) { error = -EAGAIN; @@ -1979,8 +2105,8 @@ static struct sk_buff *tun_ring_recv(struct tun_file *tfile, int noblock, current->state = TASK_INTERRUPTIBLE; while (1) { - skb = ptr_ring_consume(&tfile->tx_ring); - if (skb) + ptr = ptr_ring_consume(&tfile->tx_ring); + if (ptr) break; if (signal_pending(current)) { error = -ERESTARTSYS; @@ -1999,12 +2125,12 @@ 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; @@ -2012,23 +2138,31 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, tun_debug(KERN_INFO, tun, "tun_do_read\n"); if (!iov_iter_count(to)) { - if (skb) - kfree_skb(skb); + 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; } @@ -2165,12 +2299,12 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, { struct tun_file *tfile = container_of(sock, struct tun_file, socket); struct tun_struct *tun = tun_get(tfile); - struct sk_buff *skb = m->msg_control; + void *ptr = m->msg_control; int ret; if (!tun) { ret = -EBADFD; - goto out_free_skb; + goto out_free; } if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) { @@ -2182,7 +2316,7 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, SOL_PACKET, TUN_TX_TIMESTAMP); goto out; } - ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT, skb); + 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; @@ -2193,12 +2327,25 @@ out: out_put_tun: tun_put(tun); -out_free_skb: - if (skb) - kfree_skb(skb); +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) { struct tun_file *tfile = container_of(sock, struct tun_file, socket); @@ -2209,7 +2356,7 @@ static int tun_peek_len(struct socket *sock) if (!tun) return 0; - ret = PTR_RING_PEEK_CALL(&tfile->tx_ring, __skb_array_len_with_tag); + ret = PTR_RING_PEEK_CALL(&tfile->tx_ring, tun_ptr_peek_len); tun_put(tun); return ret; @@ -3132,7 +3279,7 @@ static int tun_queue_resize(struct tun_struct *tun) ret = ptr_ring_resize_multiple(rings, n, dev->tx_queue_len, GFP_KERNEL, - __skb_array_destroy_skb); + tun_ptr_free); kfree(rings); return ret; |