projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 531b3748 GG |
1 | /* |
| 2 | * Tap functions for AF_VSOCK sockets. | |
| 3 | * | |
| 4 | * Code based on net/netlink/af_netlink.c tap functions. | |
| 5 | * | |
| 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. | |
| 10 | */ | |
| 11 | ||
| 12 | #include <linux/module.h> | |
| 13 | #include <net/sock.h> | |
| 14 | #include <net/af_vsock.h> | |
| 15 | #include <linux/if_arp.h> | |
| 16 | ||
| 17 | static DEFINE_SPINLOCK(vsock_tap_lock); | |
| 18 | static struct list_head vsock_tap_all __read_mostly = | |
| 19 | LIST_HEAD_INIT(vsock_tap_all); | |
| 20 | ||
| 21 | int vsock_add_tap(struct vsock_tap *vt) | |
| 22 | { | |
| 23 | if (unlikely(vt->dev->type != ARPHRD_VSOCKMON)) | |
| 24 | return -EINVAL; | |
| 25 | ||
| 26 | __module_get(vt->module); | |
| 27 | ||
| 28 | spin_lock(&vsock_tap_lock); | |
| 29 | list_add_rcu(&vt->list, &vsock_tap_all); | |
| 30 | spin_unlock(&vsock_tap_lock); | |
| 31 | ||
| 32 | return 0; | |
| 33 | } | |
| 34 | EXPORT_SYMBOL_GPL(vsock_add_tap); | |
| 35 | ||
| 36 | int vsock_remove_tap(struct vsock_tap *vt) | |
| 37 | { | |
| 38 | struct vsock_tap *tmp; | |
| 39 | bool found = false; | |
| 40 | ||
| 41 | spin_lock(&vsock_tap_lock); | |
| 42 | ||
| 43 | list_for_each_entry(tmp, &vsock_tap_all, list) { | |
| 44 | if (vt == tmp) { | |
| 45 | list_del_rcu(&vt->list); | |
| 46 | found = true; | |
| 47 | goto out; | |
| 48 | } | |
| 49 | } | |
| 50 | ||
| 51 | pr_warn("vsock_remove_tap: %p not found\n", vt); | |
| 52 | out: | |
| 53 | spin_unlock(&vsock_tap_lock); | |
| 54 | ||
| 55 | synchronize_net(); | |
| 56 | ||
| 57 | if (found) | |
| 58 | module_put(vt->module); | |
| 59 | ||
| 60 | return found ? 0 : -ENODEV; | |
| 61 | } | |
| 62 | EXPORT_SYMBOL_GPL(vsock_remove_tap); | |
| 63 | ||
| 64 | static int __vsock_deliver_tap_skb(struct sk_buff *skb, | |
| 65 | struct net_device *dev) | |
| 66 | { | |
| 67 | int ret = 0; | |
| 68 | struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); | |
| 69 | ||
| 70 | if (nskb) { | |
| 71 | dev_hold(dev); | |
| 72 | ||
| 73 | nskb->dev = dev; | |
| 74 | ret = dev_queue_xmit(nskb); | |
| 75 | if (unlikely(ret > 0)) | |
| 76 | ret = net_xmit_errno(ret); | |
| 77 | ||
| 78 | dev_put(dev); | |
| 79 | } | |
| 80 | ||
| 81 | return ret; | |
| 82 | } | |
| 83 | ||
| 84 | static void __vsock_deliver_tap(struct sk_buff *skb) | |
| 85 | { | |
| 86 | int ret; | |
| 87 | struct vsock_tap *tmp; | |
| 88 | ||
| 89 | list_for_each_entry_rcu(tmp, &vsock_tap_all, list) { | |
| 90 | ret = __vsock_deliver_tap_skb(skb, tmp->dev); | |
| 91 | if (unlikely(ret)) | |
| 92 | break; | |
| 93 | } | |
| 94 | } | |
| 95 | ||
| 96 | void vsock_deliver_tap(struct sk_buff *build_skb(void *opaque), void *opaque) | |
| 97 | { | |
| 98 | struct sk_buff *skb; | |
| 99 | ||
| 100 | rcu_read_lock(); | |
| 101 | ||
| 102 | if (likely(list_empty(&vsock_tap_all))) | |
| 103 | goto out; | |
| 104 | ||
| 105 | skb = build_skb(opaque); | |
| 106 | if (skb) { | |
| 107 | __vsock_deliver_tap(skb); | |
| 108 | consume_skb(skb); | |
| 109 | } | |
| 110 | ||
| 111 | out: | |
| 112 | rcu_read_unlock(); | |
| 113 | } | |
| 114 | EXPORT_SYMBOL_GPL(vsock_deliver_tap); |