diff options
Diffstat (limited to 'drivers/net/macvtap.c')
| -rw-r--r-- | drivers/net/macvtap.c | 1229 |
1 files changed, 52 insertions, 1177 deletions
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index c27011bbe30c..a4bfc10b61dd 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -1,5 +1,6 @@ #include <linux/etherdevice.h> #include <linux/if_macvlan.h> +#include <linux/if_tap.h> #include <linux/if_vlan.h> #include <linux/interrupt.h> #include <linux/nsproxy.h> @@ -23,114 +24,16 @@ #include <linux/virtio_net.h> #include <linux/skb_array.h> -/* - * A macvtap queue is the central object of this driver, it connects - * an open character device to a macvlan interface. There can be - * multiple queues on one interface, which map back to queues - * implemented in hardware on the underlying device. - * - * macvtap_proto is used to allocate queues through the sock allocation - * mechanism. - * - */ -struct macvtap_queue { - struct sock sk; - struct socket sock; - struct socket_wq wq; - int vnet_hdr_sz; - struct macvlan_dev __rcu *vlan; - struct file *file; - unsigned int flags; - u16 queue_index; - bool enabled; - struct list_head next; - struct skb_array skb_array; -}; - -#define MACVTAP_FEATURES (IFF_VNET_HDR | IFF_MULTI_QUEUE) - -#define MACVTAP_VNET_LE 0x80000000 -#define MACVTAP_VNET_BE 0x40000000 - -#ifdef CONFIG_TUN_VNET_CROSS_LE -static inline bool macvtap_legacy_is_little_endian(struct macvtap_queue *q) -{ - return q->flags & MACVTAP_VNET_BE ? false : - virtio_legacy_is_little_endian(); -} - -static long macvtap_get_vnet_be(struct macvtap_queue *q, int __user *sp) -{ - int s = !!(q->flags & MACVTAP_VNET_BE); - - if (put_user(s, sp)) - return -EFAULT; - - return 0; -} - -static long macvtap_set_vnet_be(struct macvtap_queue *q, int __user *sp) -{ - int s; - - if (get_user(s, sp)) - return -EFAULT; - - if (s) - q->flags |= MACVTAP_VNET_BE; - else - q->flags &= ~MACVTAP_VNET_BE; - - return 0; -} -#else -static inline bool macvtap_legacy_is_little_endian(struct macvtap_queue *q) -{ - return virtio_legacy_is_little_endian(); -} - -static long macvtap_get_vnet_be(struct macvtap_queue *q, int __user *argp) -{ - return -EINVAL; -} - -static long macvtap_set_vnet_be(struct macvtap_queue *q, int __user *argp) -{ - return -EINVAL; -} -#endif /* CONFIG_TUN_VNET_CROSS_LE */ - -static inline bool macvtap_is_little_endian(struct macvtap_queue *q) -{ - return q->flags & MACVTAP_VNET_LE || - macvtap_legacy_is_little_endian(q); -} - -static inline u16 macvtap16_to_cpu(struct macvtap_queue *q, __virtio16 val) -{ - return __virtio16_to_cpu(macvtap_is_little_endian(q), val); -} - -static inline __virtio16 cpu_to_macvtap16(struct macvtap_queue *q, u16 val) -{ - return __cpu_to_virtio16(macvtap_is_little_endian(q), val); -} - -static struct proto macvtap_proto = { - .name = "macvtap", - .owner = THIS_MODULE, - .obj_size = sizeof (struct macvtap_queue), +struct macvtap_dev { + struct macvlan_dev vlan; + struct tap_dev tap; }; /* * Variables for dealing with macvtaps device numbers. */ static dev_t macvtap_major; -#define MACVTAP_NUM_DEVS (1U << MINORBITS) -static DEFINE_MUTEX(minor_lock); -static DEFINE_IDR(minor_idr); -#define GOODCOPY_LEN 128 static const void *macvtap_net_namespace(struct device *d) { struct net_device *dev = to_net_dev(d->parent); @@ -145,328 +48,33 @@ static struct class macvtap_class = { }; static struct cdev macvtap_cdev; -static const struct proto_ops macvtap_socket_ops; - #define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \ NETIF_F_TSO6 | NETIF_F_UFO) -#define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO) -#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG | NETIF_F_FRAGLIST) - -static struct macvlan_dev *macvtap_get_vlan_rcu(const struct net_device *dev) -{ - return rcu_dereference(dev->rx_handler_data); -} - -/* - * RCU usage: - * The macvtap_queue and the macvlan_dev are loosely coupled, the - * pointers from one to the other can only be read while rcu_read_lock - * or rtnl is held. - * - * Both the file and the macvlan_dev hold a reference on the macvtap_queue - * through sock_hold(&q->sk). When the macvlan_dev goes away first, - * q->vlan becomes inaccessible. When the files gets closed, - * macvtap_get_queue() fails. - * - * There may still be references to the struct sock inside of the - * queue from outbound SKBs, but these never reference back to the - * file or the dev. The data structure is freed through __sk_free - * when both our references and any pending SKBs are gone. - */ - -static int macvtap_enable_queue(struct net_device *dev, struct file *file, - struct macvtap_queue *q) -{ - struct macvlan_dev *vlan = netdev_priv(dev); - int err = -EINVAL; - - ASSERT_RTNL(); - - if (q->enabled) - goto out; - - err = 0; - rcu_assign_pointer(vlan->taps[vlan->numvtaps], q); - q->queue_index = vlan->numvtaps; - q->enabled = true; - - vlan->numvtaps++; -out: - return err; -} - -/* Requires RTNL */ -static int macvtap_set_queue(struct net_device *dev, struct file *file, - struct macvtap_queue *q) -{ - struct macvlan_dev *vlan = netdev_priv(dev); - - if (vlan->numqueues == MAX_MACVTAP_QUEUES) - return -EBUSY; - - rcu_assign_pointer(q->vlan, vlan); - rcu_assign_pointer(vlan->taps[vlan->numvtaps], q); - sock_hold(&q->sk); - - q->file = file; - q->queue_index = vlan->numvtaps; - q->enabled = true; - file->private_data = q; - list_add_tail(&q->next, &vlan->queue_list); - - vlan->numvtaps++; - vlan->numqueues++; - - return 0; -} - -static int macvtap_disable_queue(struct macvtap_queue *q) -{ - struct macvlan_dev *vlan; - struct macvtap_queue *nq; - - ASSERT_RTNL(); - if (!q->enabled) - return -EINVAL; - - vlan = rtnl_dereference(q->vlan); - - if (vlan) { - int index = q->queue_index; - BUG_ON(index >= vlan->numvtaps); - nq = rtnl_dereference(vlan->taps[vlan->numvtaps - 1]); - nq->queue_index = index; - - rcu_assign_pointer(vlan->taps[index], nq); - RCU_INIT_POINTER(vlan->taps[vlan->numvtaps - 1], NULL); - q->enabled = false; - - vlan->numvtaps--; - } - - return 0; -} - -/* - * The file owning the queue got closed, give up both - * the reference that the files holds as well as the - * one from the macvlan_dev if that still exists. - * - * Using the spinlock makes sure that we don't get - * to the queue again after destroying it. - */ -static void macvtap_put_queue(struct macvtap_queue *q) -{ - struct macvlan_dev *vlan; - - rtnl_lock(); - vlan = rtnl_dereference(q->vlan); - - if (vlan) { - if (q->enabled) - BUG_ON(macvtap_disable_queue(q)); - - vlan->numqueues--; - RCU_INIT_POINTER(q->vlan, NULL); - sock_put(&q->sk); - list_del_init(&q->next); - } - - rtnl_unlock(); - - synchronize_rcu(); - sock_put(&q->sk); -} - -/* - * Select a queue based on the rxq of the device on which this packet - * arrived. If the incoming device is not mq, calculate a flow hash - * to select a queue. If all fails, find the first available queue. - * Cache vlan->numvtaps since it can become zero during the execution - * of this function. - */ -static struct macvtap_queue *macvtap_get_queue(struct net_device *dev, - struct sk_buff *skb) -{ - struct macvlan_dev *vlan = netdev_priv(dev); - struct macvtap_queue *tap = NULL; - /* Access to taps array is protected by rcu, but access to numvtaps - * isn't. Below we use it to lookup a queue, but treat it as a hint - * and validate that the result isn't NULL - in case we are - * racing against queue removal. - */ - int numvtaps = ACCESS_ONCE(vlan->numvtaps); - __u32 rxq; - - if (!numvtaps) - goto out; - - if (numvtaps == 1) - goto single; - - /* Check if we can use flow to select a queue */ - rxq = skb_get_hash(skb); - if (rxq) { - tap = rcu_dereference(vlan->taps[rxq % numvtaps]); - goto out; - } - - if (likely(skb_rx_queue_recorded(skb))) { - rxq = skb_get_rx_queue(skb); - - while (unlikely(rxq >= numvtaps)) - rxq -= numvtaps; - tap = rcu_dereference(vlan->taps[rxq]); - goto out; - } - -single: - tap = rcu_dereference(vlan->taps[0]); -out: - return tap; -} - -/* - * The net_device is going away, give up the reference - * that it holds on all queues and safely set the pointer - * from the queues to NULL. - */ -static void macvtap_del_queues(struct net_device *dev) +static void macvtap_count_tx_dropped(struct tap_dev *tap) { - struct macvlan_dev *vlan = netdev_priv(dev); - struct macvtap_queue *q, *tmp; + struct macvtap_dev *vlantap = container_of(tap, struct macvtap_dev, tap); + struct macvlan_dev *vlan = &vlantap->vlan; - ASSERT_RTNL(); - list_for_each_entry_safe(q, tmp, &vlan->queue_list, next) { - list_del_init(&q->next); - RCU_INIT_POINTER(q->vlan, NULL); - if (q->enabled) - vlan->numvtaps--; - vlan->numqueues--; - sock_put(&q->sk); - } - BUG_ON(vlan->numvtaps); - BUG_ON(vlan->numqueues); - /* guarantee that any future macvtap_set_queue will fail */ - vlan->numvtaps = MAX_MACVTAP_QUEUES; + this_cpu_inc(vlan->pcpu_stats->tx_dropped); } -static rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb) +static void macvtap_count_rx_dropped(struct tap_dev *tap) { - struct sk_buff *skb = *pskb; - struct net_device *dev = skb->dev; - struct macvlan_dev *vlan; - struct macvtap_queue *q; - netdev_features_t features = TAP_FEATURES; - - vlan = macvtap_get_vlan_rcu(dev); - if (!vlan) - return RX_HANDLER_PASS; - - q = macvtap_get_queue(dev, skb); - if (!q) - return RX_HANDLER_PASS; - - if (__skb_array_full(&q->skb_array)) - goto drop; - - skb_push(skb, ETH_HLEN); - - /* Apply the forward feature mask so that we perform segmentation - * according to users wishes. This only works if VNET_HDR is - * enabled. - */ - if (q->flags & IFF_VNET_HDR) - features |= vlan->tap_features; - if (netif_needs_gso(skb, features)) { - struct sk_buff *segs = __skb_gso_segment(skb, features, false); - - if (IS_ERR(segs)) - goto drop; + struct macvtap_dev *vlantap = container_of(tap, struct macvtap_dev, tap); + struct macvlan_dev *vlan = &vlantap->vlan; - if (!segs) { - if (skb_array_produce(&q->skb_array, skb)) - goto drop; - goto wake_up; - } - - consume_skb(skb); - while (segs) { - struct sk_buff *nskb = segs->next; - - segs->next = NULL; - if (skb_array_produce(&q->skb_array, segs)) { - kfree_skb(segs); - kfree_skb_list(nskb); - break; - } - segs = nskb; - } - } else { - /* If we receive a partial checksum and the tap side - * doesn't support checksum offload, compute the checksum. - * Note: it doesn't matter which checksum feature to - * check, we either support them all or none. - */ - if (skb->ip_summed == CHECKSUM_PARTIAL && - !(features & NETIF_F_CSUM_MASK) && - skb_checksum_help(skb)) - goto drop; - if (skb_array_produce(&q->skb_array, skb)) - goto drop; - } - -wake_up: - wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND); - return RX_HANDLER_CONSUMED; - -drop: - /* Count errors/drops only here, thus don't care about args. */ macvlan_count_rx(vlan, 0, 0, 0); - kfree_skb(skb); - return RX_HANDLER_CONSUMED; -} - -static int macvtap_get_minor(struct macvlan_dev *vlan) -{ - int retval = -ENOMEM; - - mutex_lock(&minor_lock); - retval = idr_alloc(&minor_idr, vlan, 1, MACVTAP_NUM_DEVS, GFP_KERNEL); - if (retval >= 0) { - vlan->minor = retval; - } else if (retval == -ENOSPC) { - netdev_err(vlan->dev, "Too many macvtap devices\n"); - retval = -EINVAL; - } - mutex_unlock(&minor_lock); - return retval < 0 ? retval : 0; -} - -static void macvtap_free_minor(struct macvlan_dev *vlan) -{ - mutex_lock(&minor_lock); - if (vlan->minor) { - idr_remove(&minor_idr, vlan->minor); - vlan->minor = 0; - } - mutex_unlock(&minor_lock); } -static struct net_device *dev_get_by_macvtap_minor(int minor) +static void macvtap_update_features(struct tap_dev *tap, + netdev_features_t features) { - struct net_device *dev = NULL; - struct macvlan_dev *vlan; + struct macvtap_dev *vlantap = container_of(tap, struct macvtap_dev, tap); + struct macvlan_dev *vlan = &vlantap->vlan; - mutex_lock(&minor_lock); - vlan = idr_find(&minor_idr, minor); - if (vlan) { - dev = vlan->dev; - dev_hold(dev); - } - mutex_unlock(&minor_lock); - return dev; + vlan->set_features = features; + netdev_update_features(vlan->dev); } static int macvtap_newlink(struct net *src_net, @@ -474,17 +82,24 @@ static int macvtap_newlink(struct net *src_net, struct nlattr *tb[], struct nlattr *data[]) { - struct macvlan_dev *vlan = netdev_priv(dev); + struct macvtap_dev *vlantap = netdev_priv(dev); int err; - INIT_LIST_HEAD(&vlan->queue_list); + INIT_LIST_HEAD(&vlantap->tap.queue_list); /* Since macvlan supports all offloads by default, make * tap support all offloads also. */ - vlan->tap_features = TUN_OFFLOADS; + vlantap->tap.tap_features = TUN_OFFLOADS; + + /* Register callbacks for rx/tx drops accounting and updating + * net_device features + */ + vlantap->tap.count_tx_dropped = macvtap_count_tx_dropped; + vlantap->tap.count_rx_dropped = macvtap_count_rx_dropped; + vlantap->tap.update_features = macvtap_update_features; - err = netdev_rx_handler_register(dev, macvtap_handle_frame, vlan); + err = netdev_rx_handler_register(dev, tap_handle_frame, &vlantap->tap); if (err) return err; @@ -497,14 +112,18 @@ static int macvtap_newlink(struct net *src_net, return err; } + vlantap->tap.dev = vlantap->vlan.dev; + return 0; } static void macvtap_dellink(struct net_device *dev, struct list_head *head) { + struct macvtap_dev *vlantap = netdev_priv(dev); + netdev_rx_handler_unregister(dev); - macvtap_del_queues(dev); + tap_del_queues(&vlantap->tap); macvlan_dellink(dev, head); } @@ -519,749 +138,14 @@ static struct rtnl_link_ops macvtap_link_ops __read_mostly = { .setup = macvtap_setup, .newlink = macvtap_newlink, .dellink = macvtap_dellink, + .priv_size = sizeof(struct macvtap_dev), }; - -static void macvtap_sock_write_space(struct sock *sk) -{ - wait_queue_head_t *wqueue; - - if (!sock_writeable(sk) || - !test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags)) - return; - - wqueue = sk_sleep(sk); - if (wqueue && waitqueue_active(wqueue)) - wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND); -} - -static void macvtap_sock_destruct(struct sock *sk) -{ - struct macvtap_queue *q = container_of(sk, struct macvtap_queue, sk); - - skb_array_cleanup(&q->skb_array); -} - -static int macvtap_open(struct inode *inode, struct file *file) -{ - struct net *net = current->nsproxy->net_ns; - struct net_device *dev; - struct macvtap_queue *q; - int err = -ENODEV; - - rtnl_lock(); - dev = dev_get_by_macvtap_minor(iminor(inode)); - if (!dev) - goto err; - - err = -ENOMEM; - q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL, - &macvtap_proto, 0); - if (!q) - goto err; - - RCU_INIT_POINTER(q->sock.wq, &q->wq); - init_waitqueue_head(&q->wq.wait); - q->sock.type = SOCK_RAW; - q->sock.state = SS_CONNECTED; - q->sock.file = file; - q->sock.ops = &macvtap_socket_ops; - sock_init_data(&q->sock, &q->sk); - q->sk.sk_write_space = macvtap_sock_write_space; - q->sk.sk_destruct = macvtap_sock_destruct; - q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP; - q->vnet_hdr_sz = sizeof(struct virtio_net_hdr); - - /* - * so far only KVM virtio_net uses macvtap, enable zero copy between - * guest kernel and host kernel when lower device supports zerocopy - * - * The macvlan supports zerocopy iff the lower device supports zero - * copy so we don't have to look at the lower device directly. - */ - if ((dev->features & NETIF_F_HIGHDMA) && (dev->features & NETIF_F_SG)) - sock_set_flag(&q->sk, SOCK_ZEROCOPY); - - err = -ENOMEM; - if (skb_array_init(&q->skb_array, dev->tx_queue_len, GFP_KERNEL)) - goto err_array; - - err = macvtap_set_queue(dev, file, q); - if (err) - goto err_queue; - - dev_put(dev); - - rtnl_unlock(); - return err; - -err_queue: - skb_array_cleanup(&q->skb_array); -err_array: - sock_put(&q->sk); -err: - if (dev) - dev_put(dev); - - rtnl_unlock(); - return err; -} - -static int macvtap_release(struct inode *inode, struct file *file) -{ - struct macvtap_queue *q = file->private_data; - macvtap_put_queue(q); - return 0; -} - -static unsigned int macvtap_poll(struct file *file, poll_table * wait) -{ - struct macvtap_queue *q = file->private_data; - unsigned int mask = POLLERR; - - if (!q) - goto out; - - mask = 0; - poll_wait(file, &q->wq.wait, wait); - - if (!skb_array_empty(&q->skb_array)) - mask |= POLLIN | POLLRDNORM; - - if (sock_writeable(&q->sk) || - (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &q->sock.flags) && - sock_writeable(&q->sk))) - mask |= POLLOUT | POLLWRNORM; - -out: - return mask; -} - -static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad, - size_t len, size_t linear, - int noblock, int *err) -{ - struct sk_buff *skb; - - /* Under a page? Don't bother with paged skb. */ - if (prepad + len < PAGE_SIZE || !linear) - linear = len; - - skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, - err, 0); - if (!skb) - return NULL; - - skb_reserve(skb, prepad); - skb_put(skb, linear); - skb->data_len = len - linear; - skb->len += len - linear; - - return skb; -} - -/* Neighbour code has some assumptions on HH_DATA_MOD alignment */ -#define MACVTAP_RESERVE HH_DATA_OFF(ETH_HLEN) - -/* Get packet from user space buffer */ -static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, - struct iov_iter *from, int noblock) -{ - int good_linear = SKB_MAX_HEAD(MACVTAP_RESERVE); - struct sk_buff *skb; - struct macvlan_dev *vlan; - unsigned long total_len = iov_iter_count(from); - unsigned long len = total_len; - int err; - struct virtio_net_hdr vnet_hdr = { 0 }; - int vnet_hdr_len = 0; - int copylen = 0; - int depth; - bool zerocopy = false; - size_t linear; - - if (q->flags & IFF_VNET_HDR) { - vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz); - - err = -EINVAL; - if (len < vnet_hdr_len) - goto err; - len -= vnet_hdr_len; - - err = -EFAULT; - if (!copy_from_iter_full(&vnet_hdr, sizeof(vnet_hdr), from)) - goto err; - iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr)); - if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && - macvtap16_to_cpu(q, vnet_hdr.csum_start) + - macvtap16_to_cpu(q, vnet_hdr.csum_offset) + 2 > - macvtap16_to_cpu(q, vnet_hdr.hdr_len)) - vnet_hdr.hdr_len = cpu_to_macvtap16(q, - macvtap16_to_cpu(q, vnet_hdr.csum_start) + - macvtap16_to_cpu(q, vnet_hdr.csum_offset) + 2); - err = -EINVAL; - if (macvtap16_to_cpu(q, vnet_hdr.hdr_len) > len) - goto err; - } - - err = -EINVAL; - if (unlikely(len < ETH_HLEN)) - goto err; - - if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) { - struct iov_iter i; - - copylen = vnet_hdr.hdr_len ? - macvtap16_to_cpu(q, vnet_hdr.hdr_len) : GOODCOPY_LEN; - if (copylen > good_linear) - copylen = good_linear; - else if (copylen < ETH_HLEN) - copylen = ETH_HLEN; - linear = copylen; - i = *from; - iov_iter_advance(&i, copylen); - if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) - zerocopy = true; - } - - if (!zerocopy) { - copylen = len; - linear = macvtap16_to_cpu(q, vnet_hdr.hdr_len); - if (linear > good_linear) - linear = good_linear; - else if (linear < ETH_HLEN) - linear = ETH_HLEN; - } - - skb = macvtap_alloc_skb(&q->sk, MACVTAP_RESERVE, copylen, - linear, noblock, &err); - if (!skb) - goto err; - - if (zerocopy) - err = zerocopy_sg_from_iter(skb, from); - else - err = skb_copy_datagram_from_iter(skb, 0, from, len); - - if (err) - goto err_kfree; - - skb_set_network_header(skb, ETH_HLEN); - skb_reset_mac_header(skb); - skb->protocol = eth_hdr(skb)->h_proto; - - if (vnet_hdr_len) { - err = virtio_net_hdr_to_skb(skb, &vnet_hdr, - macvtap_is_little_endian(q)); - if (err) - goto err_kfree; - } - - skb_probe_transport_header(skb, ETH_HLEN); - - /* Move network header to the right position for VLAN tagged packets */ - if ((skb->protocol == htons(ETH_P_8021Q) || - skb->protocol == htons(ETH_P_8021AD)) && - __vlan_get_protocol(skb, skb->protocol, &depth) != 0) - skb_set_network_header(skb, depth); - - rcu_read_lock(); - vlan = rcu_dereference(q->vlan); - /* copy skb_ubuf_info for callback when skb has no error */ - if (zerocopy) { - skb_shinfo(skb)->destructor_arg = m->msg_control; - skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; - skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; - } else if (m && m->msg_control) { - struct ubuf_info *uarg = m->msg_control; - uarg->callback(uarg, false); - } - - if (vlan) { - skb->dev = vlan->dev; - dev_queue_xmit(skb); - } else { - kfree_skb(skb); - } - rcu_read_unlock(); - - return total_len; - -err_kfree: - kfree_skb(skb); - -err: - rcu_read_lock(); - vlan = rcu_dereference(q->vlan); - if (vlan) - this_cpu_inc(vlan->pcpu_stats->tx_dropped); - rcu_read_unlock(); - - return err; -} - -static ssize_t macvtap_write_iter(struct kiocb *iocb, struct iov_iter *from) -{ - struct file *file = iocb->ki_filp; - struct macvtap_queue *q = file->private_data; - - return macvtap_get_user(q, NULL, from, file->f_flags & O_NONBLOCK); -} - -/* Put packet to the user space buffer */ -static ssize_t macvtap_put_user(struct macvtap_queue *q, - const struct sk_buff *skb, - struct iov_iter *iter) -{ - int ret; - int vnet_hdr_len = 0; - int vlan_offset = 0; - int total; - - if (q->flags & IFF_VNET_HDR) { - struct virtio_net_hdr vnet_hdr; - vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz); - if (iov_iter_count(iter) < vnet_hdr_len) - return -EINVAL; - - if (virtio_net_hdr_from_skb(skb, &vnet_hdr, - macvtap_is_little_endian(q), true)) - BUG(); - - if (copy_to_iter(&vnet_hdr, sizeof(vnet_hdr), iter) != - sizeof(vnet_hdr)) - return -EFAULT; - - iov_iter_advance(iter, vnet_hdr_len - sizeof(vnet_hdr)); - } - total = vnet_hdr_len; - total += skb->len; - - if (skb_vlan_tag_present(skb)) { - struct { - __be16 h_vlan_proto; - __be16 h_vlan_TCI; - } veth; - veth.h_vlan_proto = skb->vlan_proto; - veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb)); - - vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); - total += VLAN_HLEN; - - ret = skb_copy_datagram_iter(skb, 0, iter, vlan_offset); - if (ret || !iov_iter_count(iter)) - goto done; - - ret = copy_to_iter(&veth, sizeof(veth), iter); - if (ret != sizeof(veth) || !iov_iter_count(iter)) - goto done; - } - - ret = skb_copy_datagram_iter(skb, vlan_offset, iter, - skb->len - vlan_offset); - -done: - return ret ? ret : total; -} - -static ssize_t macvtap_do_read(struct macvtap_queue *q, - struct iov_iter *to, - int noblock) -{ - DEFINE_WAIT(wait); - struct sk_buff *skb; - ssize_t ret = 0; - - if (!iov_iter_count(to)) - return 0; - - while (1) { - if (!noblock) - prepare_to_wait(sk_sleep(&q->sk), &wait, - TASK_INTERRUPTIBLE); - - /* Read frames from the queue */ - skb = skb_array_consume(&q->skb_array); - if (skb) - break; - if (noblock) { - ret = -EAGAIN; - break; - } - if (signal_pending(current)) { - ret = -ERESTARTSYS; - break; - } - /* Nothing to read, let's sleep */ - schedule(); - } - if (!noblock) - finish_wait(sk_sleep(&q->sk), &wait); - - if (skb) { - ret = macvtap_put_user(q, skb, to); - if (unlikely(ret < 0)) - kfree_skb(skb); - else - consume_skb(skb); - } - return ret; -} - -static ssize_t macvtap_read_iter(struct kiocb *iocb, struct iov_iter *to) -{ - struct file *file = iocb->ki_filp; - struct macvtap_queue *q = file->private_data; - ssize_t len = iov_iter_count(to), ret; - - ret = macvtap_do_read(q, to, file->f_flags & O_NONBLOCK); - ret = min_t(ssize_t, ret, len); - if (ret > 0) - iocb->ki_pos = ret; - return ret; -} - -static struct macvlan_dev *macvtap_get_vlan(struct macvtap_queue *q) -{ - struct macvlan_dev *vlan; - - ASSERT_RTNL(); - vlan = rtnl_dereference(q->vlan); - if (vlan) - dev_hold(vlan->dev); - - return vlan; -} - -static void macvtap_put_vlan(struct macvlan_dev *vlan) -{ - dev_put(vlan->dev); -} - -static int macvtap_ioctl_set_queue(struct file *file, unsigned int flags) -{ - struct macvtap_queue *q = file->private_data; - struct macvlan_dev *vlan; - int ret; - - vlan = macvtap_get_vlan(q); - if (!vlan) - return -EINVAL; - - if (flags & IFF_ATTACH_QUEUE) - ret = macvtap_enable_queue(vlan->dev, file, q); - else if (flags & IFF_DETACH_QUEUE) - ret = macvtap_disable_queue(q); - else - ret = -EINVAL; - - macvtap_put_vlan(vlan); - return ret; -} - -static int set_offload(struct macvtap_queue *q, unsigned long arg) -{ - struct macvlan_dev *vlan; - netdev_features_t features; - netdev_features_t feature_mask = 0; - - vlan = rtnl_dereference(q->vlan); - if (!vlan) - return -ENOLINK; - - features = vlan->dev->features; - - if (arg & TUN_F_CSUM) { - feature_mask = NETIF_F_HW_CSUM; - - if (arg & (TUN_F_TSO4 | TUN_F_TSO6)) { - if (arg & TUN_F_TSO_ECN) - feature_mask |= NETIF_F_TSO_ECN; - if (arg & TUN_F_TSO4) - feature_mask |= NETIF_F_TSO; - if (arg & TUN_F_TSO6) - feature_mask |= NETIF_F_TSO6; - } - - if (arg & TUN_F_UFO) - feature_mask |= NETIF_F_UFO; - } - - /* tun/tap driver inverts the usage for TSO offloads, where - * setting the TSO bit means that the userspace wants to - * accept TSO frames and turning it off means that user space - * does not support TSO. - * For macvtap, we have to invert it to mean the same thing. - * When user space turns off TSO, we turn off GSO/LRO so that - * user-space will not receive TSO frames. - */ - if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_UFO)) - features |= RX_OFFLOADS; - else - features &= ~RX_OFFLOADS; - - /* tap_features are the same as features on tun/tap and - * reflect user expectations. - */ - vlan->tap_features = feature_mask; - vlan->set_features = features; - netdev_update_features(vlan->dev); - - return 0; -} - -/* - * provide compatibility with generic tun/tap interface - */ -static long macvtap_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - struct macvtap_queue *q = file->private_data; - struct macvlan_dev *vlan; - void __user *argp = (void __user *)arg; - struct ifreq __user *ifr = argp; - unsigned int __user *up = argp; - unsigned short u; - int __user *sp = argp; - struct sockaddr sa; - int s; - int ret; - - switch (cmd) { - case TUNSETIFF: - /* ignore the name, just look at flags */ - if (get_user(u, &ifr->ifr_flags)) - return -EFAULT; - - ret = 0; - if ((u & ~MACVTAP_FEATURES) != (IFF_NO_PI | IFF_TAP)) - ret = -EINVAL; - else - q->flags = (q->flags & ~MACVTAP_FEATURES) | u; - - return ret; - - case TUNGETIFF: - rtnl_lock(); - vlan = macvtap_get_vlan(q); - if (!vlan) { - rtnl_unlock(); - return -ENOLINK; - } - - ret = 0; - u = q->flags; - if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) || - put_user(u, &ifr->ifr_flags)) - ret = -EFAULT; - macvtap_put_vlan(vlan); - rtnl_unlock(); - return ret; - - case TUNSETQUEUE: - if (get_user(u, &ifr->ifr_flags)) - return -EFAULT; - rtnl_lock(); - ret = macvtap_ioctl_set_queue(file, u); - rtnl_unlock(); - return ret; - - case TUNGETFEATURES: - if (put_user(IFF_TAP | IFF_NO_PI | MACVTAP_FEATURES, up)) - return -EFAULT; - return 0; - - case TUNSETSNDBUF: - if (get_user(s, sp)) - return -EFAULT; - - q->sk.sk_sndbuf = s; - return 0; - - case TUNGETVNETHDRSZ: - s = q->vnet_hdr_sz; - if (put_user(s, sp)) - return -EFAULT; - return 0; - - case TUNSETVNETHDRSZ: - if (get_user(s, sp)) - return -EFAULT; - if (s < (int)sizeof(struct virtio_net_hdr)) - return -EINVAL; - - q->vnet_hdr_sz = s; - return 0; - - case TUNGETVNETLE: - s = !!(q->flags & MACVTAP_VNET_LE); - if (put_user(s, sp)) - return -EFAULT; - return 0; - - case TUNSETVNETLE: - if (get_user(s, sp)) - return -EFAULT; - if (s) - q->flags |= MACVTAP_VNET_LE; - else - q->flags &= ~MACVTAP_VNET_LE; - return 0; - - case TUNGETVNETBE: - return macvtap_get_vnet_be(q, sp); - - case TUNSETVNETBE: - return macvtap_set_vnet_be(q, sp); - - case TUNSETOFFLOAD: - /* let the user check for future flags */ - if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 | - TUN_F_TSO_ECN | TUN_F_UFO)) - return -EINVAL; - - rtnl_lock(); - ret = set_offload(q, arg); - rtnl_unlock(); - return ret; - - case SIOCGIFHWADDR: - rtnl_lock(); - vlan = macvtap_get_vlan(q); - if (!vlan) { - rtnl_unlock(); - return -ENOLINK; - } - ret = 0; - u = vlan->dev->type; - if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) || - copy_to_user(&ifr->ifr_hwaddr.sa_data, vlan->dev->dev_addr, ETH_ALEN) || - put_user(u, &ifr->ifr_hwaddr.sa_family)) - ret = -EFAULT; - macvtap_put_vlan(vlan); - rtnl_unlock(); - return ret; - - case SIOCSIFHWADDR: - if (copy_from_user(&sa, &ifr->ifr_hwaddr, sizeof(sa))) - return -EFAULT; - rtnl_lock(); - vlan = macvtap_get_vlan(q); - if (!vlan) { - rtnl_unlock(); - return -ENOLINK; - } - ret = dev_set_mac_address(vlan->dev, &sa); - macvtap_put_vlan(vlan); - rtnl_unlock(); - return ret; - - default: - return -EINVAL; - } -} - -#ifdef CONFIG_COMPAT -static long macvtap_compat_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); -} -#endif - -static const struct file_operations macvtap_fops = { - .owner = THIS_MODULE, - .open = macvtap_open, - .release = macvtap_release, - .read_iter = macvtap_read_iter, - .write_iter = macvtap_write_iter, - .poll = macvtap_poll, - .llseek = no_llseek, - .unlocked_ioctl = macvtap_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = macvtap_compat_ioctl, -#endif -}; - -static int macvtap_sendmsg(struct socket *sock, struct msghdr *m, - size_t total_len) -{ - struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock); - return macvtap_get_user(q, m, &m->msg_iter, m->msg_flags & MSG_DONTWAIT); -} - -static int macvtap_recvmsg(struct socket *sock, struct msghdr *m, - size_t total_len, int flags) -{ - struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock); - int ret; - if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) - return -EINVAL; - ret = macvtap_do_read(q, &m->msg_iter, flags & MSG_DONTWAIT); - if (ret > total_len) { - m->msg_flags |= MSG_TRUNC; - ret = flags & MSG_TRUNC ? ret : total_len; - } - return ret; -} - -static int macvtap_peek_len(struct socket *sock) -{ - struct macvtap_queue *q = container_of(sock, struct macvtap_queue, - sock); - return skb_array_peek_len(&q->skb_array); -} - -/* Ops structure to mimic raw sockets with tun */ -static const struct proto_ops macvtap_socket_ops = { - .sendmsg = macvtap_sendmsg, - .recvmsg = macvtap_recvmsg, - .peek_len = macvtap_peek_len, -}; - -/* Get an underlying socket object from tun file. Returns error unless file is - * attached to a device. The returned object works like a packet socket, it - * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for - * holding a reference to the file for as long as the socket is in use. */ -struct socket *macvtap_get_socket(struct file *file) -{ - struct macvtap_queue *q; - if (file->f_op != &macvtap_fops) - return ERR_PTR(-EINVAL); - q = file->private_data; - if (!q) - return ERR_PTR(-EBADFD); - return &q->sock; -} -EXPORT_SYMBOL_GPL(macvtap_get_socket); - -static int macvtap_queue_resize(struct macvlan_dev *vlan) -{ - struct net_device *dev = vlan->dev; - struct macvtap_queue *q; - struct skb_array **arrays; - int n = vlan->numqueues; - int ret, i = 0; - - arrays = kmalloc(sizeof *arrays * n, GFP_KERNEL); - if (!arrays) - return -ENOMEM; - - list_for_each_entry(q, &vlan->queue_list, next) - arrays[i++] = &q->skb_array; - - ret = skb_array_resize_multiple(arrays, n, - dev->tx_queue_len, GFP_KERNEL); - - kfree(arrays); - return ret; -} - static int macvtap_device_event(struct notifier_block *unused, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); - struct macvlan_dev *vlan; + struct macvtap_dev *vlantap; struct device *classdev; dev_t devt; int err; @@ -1271,7 +155,7 @@ static int macvtap_device_event(struct notifier_block *unused, return NOTIFY_DONE; snprintf(tap_name, IFNAMSIZ, "tap%d", dev->ifindex); - vlan = netdev_priv(dev); + vlantap = netdev_priv(dev); switch (event) { case NETDEV_REGISTER: @@ -1279,15 +163,15 @@ static int macvtap_device_event(struct notifier_block *unused, * been registered but before register_netdevice has * finished running. */ - err = macvtap_get_minor(vlan); + err = tap_get_minor(macvtap_major, &vlantap->tap); if (err) return notifier_from_errno(err); - devt = MKDEV(MAJOR(macvtap_major), vlan->minor); + devt = MKDEV(MAJOR(macvtap_major), vlantap->tap.minor); classdev = device_create(&macvtap_class, &dev->dev, devt, dev, tap_name); if (IS_ERR(classdev)) { - macvtap_free_minor(vlan); + tap_free_minor(macvtap_major, &vlantap->tap); return notifier_from_errno(PTR_ERR(classdev)); } err = sysfs_create_link(&dev->dev.kobj, &classdev->kobj, @@ -1297,15 +181,15 @@ static int macvtap_device_event(struct notifier_block *unused, break; case NETDEV_UNREGISTER: /* vlan->minor == 0 if NETDEV_REGISTER above failed */ - if (vlan->minor == 0) + if (vlantap->tap.minor == 0) break; sysfs_remove_link(&dev->dev.kobj, tap_name); - devt = MKDEV(MAJOR(macvtap_major), vlan->minor); + devt = MKDEV(MAJOR(macvtap_major), vlantap->tap.minor); device_destroy(&macvtap_class, devt); - macvtap_free_minor(vlan); + tap_free_minor(macvtap_major, &vlantap->tap); break; case NETDEV_CHANGE_TX_QUEUE_LEN: - if (macvtap_queue_resize(vlan)) + if (tap_queue_resize(&vlantap->tap)) return NOTIFY_BAD; break; } @@ -1321,38 +205,31 @@ static int macvtap_init(void) { int err; - err = alloc_chrdev_region(&macvtap_major, 0, - MACVTAP_NUM_DEVS, "macvtap"); - if (err) - goto out1; + err = tap_create_cdev(&macvtap_cdev, &macvtap_major, "macvtap"); - cdev_init(&macvtap_cdev, &macvtap_fops); - err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS); if (err) - goto out2; + goto out1; err = class_register(&macvtap_class); if (err) - goto out3; + goto out2; err = register_netdevice_notifier(&macvtap_notifier_block); if (err) - goto out4; + goto out3; err = macvlan_link_register(&macvtap_link_ops); if (err) - goto out5; + goto out4; return 0; -out5: - unregister_netdevice_notifier(&macvtap_notifier_block); out4: - class_unregister(&macvtap_class); + unregister_netdevice_notifier(&macvtap_notifier_block); out3: - cdev_del(&macvtap_cdev); + class_unregister(&macvtap_class); out2: - unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS); + tap_destroy_cdev(macvtap_major, &macvtap_cdev); out1: return err; } @@ -1363,9 +240,7 @@ static void macvtap_exit(void) rtnl_link_unregister(&macvtap_link_ops); unregister_netdevice_notifier(&macvtap_notifier_block); class_unregister(&macvtap_class); - cdev_del(&macvtap_cdev); - unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS); - idr_destroy(&minor_idr); + tap_destroy_cdev(macvtap_major, &macvtap_cdev); } module_exit(macvtap_exit); |