2 * Tap functions for AF_VSOCK sockets.
4 * Code based on net/netlink/af_netlink.c tap functions.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #include <linux/module.h>
14 #include <net/af_vsock.h>
15 #include <linux/if_arp.h>
17 static DEFINE_SPINLOCK(vsock_tap_lock);
18 static struct list_head vsock_tap_all __read_mostly =
19 LIST_HEAD_INIT(vsock_tap_all);
21 int vsock_add_tap(struct vsock_tap *vt)
23 if (unlikely(vt->dev->type != ARPHRD_VSOCKMON))
26 __module_get(vt->module);
28 spin_lock(&vsock_tap_lock);
29 list_add_rcu(&vt->list, &vsock_tap_all);
30 spin_unlock(&vsock_tap_lock);
34 EXPORT_SYMBOL_GPL(vsock_add_tap);
36 int vsock_remove_tap(struct vsock_tap *vt)
38 struct vsock_tap *tmp;
41 spin_lock(&vsock_tap_lock);
43 list_for_each_entry(tmp, &vsock_tap_all, list) {
45 list_del_rcu(&vt->list);
51 pr_warn("vsock_remove_tap: %p not found\n", vt);
53 spin_unlock(&vsock_tap_lock);
58 module_put(vt->module);
60 return found ? 0 : -ENODEV;
62 EXPORT_SYMBOL_GPL(vsock_remove_tap);
64 static int __vsock_deliver_tap_skb(struct sk_buff *skb,
65 struct net_device *dev)
68 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
74 ret = dev_queue_xmit(nskb);
75 if (unlikely(ret > 0))
76 ret = net_xmit_errno(ret);
84 static void __vsock_deliver_tap(struct sk_buff *skb)
87 struct vsock_tap *tmp;
89 list_for_each_entry_rcu(tmp, &vsock_tap_all, list) {
90 ret = __vsock_deliver_tap_skb(skb, tmp->dev);
96 void vsock_deliver_tap(struct sk_buff *build_skb(void *opaque), void *opaque)
102 if (likely(list_empty(&vsock_tap_all)))
105 skb = build_skb(opaque);
107 __vsock_deliver_tap(skb);
114 EXPORT_SYMBOL_GPL(vsock_deliver_tap);