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path: root/net/vmw_vsock/af_vsock_tap.c
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Diffstat (limited to 'net/vmw_vsock/af_vsock_tap.c')
-rw-r--r--net/vmw_vsock/af_vsock_tap.c114
1 files changed, 114 insertions, 0 deletions
diff --git a/net/vmw_vsock/af_vsock_tap.c b/net/vmw_vsock/af_vsock_tap.c
new file mode 100644
index 000000000000..98f09b539366
--- /dev/null
+++ b/net/vmw_vsock/af_vsock_tap.c
@@ -0,0 +1,114 @@
+/*
+ * Tap functions for AF_VSOCK sockets.
+ *
+ * Code based on net/netlink/af_netlink.c tap functions.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <net/sock.h>
+#include <net/af_vsock.h>
+#include <linux/if_arp.h>
+
+static DEFINE_SPINLOCK(vsock_tap_lock);
+static struct list_head vsock_tap_all __read_mostly =
+ LIST_HEAD_INIT(vsock_tap_all);
+
+int vsock_add_tap(struct vsock_tap *vt)
+{
+ if (unlikely(vt->dev->type != ARPHRD_VSOCKMON))
+ return -EINVAL;
+
+ __module_get(vt->module);
+
+ spin_lock(&vsock_tap_lock);
+ list_add_rcu(&vt->list, &vsock_tap_all);
+ spin_unlock(&vsock_tap_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vsock_add_tap);
+
+int vsock_remove_tap(struct vsock_tap *vt)
+{
+ struct vsock_tap *tmp;
+ bool found = false;
+
+ spin_lock(&vsock_tap_lock);
+
+ list_for_each_entry(tmp, &vsock_tap_all, list) {
+ if (vt == tmp) {
+ list_del_rcu(&vt->list);
+ found = true;
+ goto out;
+ }
+ }
+
+ pr_warn("vsock_remove_tap: %p not found\n", vt);
+out:
+ spin_unlock(&vsock_tap_lock);
+
+ synchronize_net();
+
+ if (found)
+ module_put(vt->module);
+
+ return found ? 0 : -ENODEV;
+}
+EXPORT_SYMBOL_GPL(vsock_remove_tap);
+
+static int __vsock_deliver_tap_skb(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ int ret = 0;
+ struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
+
+ if (nskb) {
+ dev_hold(dev);
+
+ nskb->dev = dev;
+ ret = dev_queue_xmit(nskb);
+ if (unlikely(ret > 0))
+ ret = net_xmit_errno(ret);
+
+ dev_put(dev);
+ }
+
+ return ret;
+}
+
+static void __vsock_deliver_tap(struct sk_buff *skb)
+{
+ int ret;
+ struct vsock_tap *tmp;
+
+ list_for_each_entry_rcu(tmp, &vsock_tap_all, list) {
+ ret = __vsock_deliver_tap_skb(skb, tmp->dev);
+ if (unlikely(ret))
+ break;
+ }
+}
+
+void vsock_deliver_tap(struct sk_buff *build_skb(void *opaque), void *opaque)
+{
+ struct sk_buff *skb;
+
+ rcu_read_lock();
+
+ if (likely(list_empty(&vsock_tap_all)))
+ goto out;
+
+ skb = build_skb(opaque);
+ if (skb) {
+ __vsock_deliver_tap(skb);
+ consume_skb(skb);
+ }
+
+out:
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(vsock_deliver_tap);