From: Gerard Garcia <ggar...@deic.uab.cat>
Add tap functions that can be used by the vsock transports to
deliver packets to vsockmon virtual network devices.
Signed-off-by: Gerard Garcia <ggar...@deic.uab.cat>
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
v4:
* Call synchronize_net() before module_put() [Michael]
v3:
* Include missing <linux/module.h> header in af_vsock_tap.c
---
net/vmw_vsock/Makefile | 2 +-
include/net/af_vsock.h | 13 ++++++
include/uapi/linux/if_arp.h | 1 +
net/vmw_vsock/af_vsock_tap.c | 107 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 122 insertions(+), 1 deletion(-)
create mode 100644 net/vmw_vsock/af_vsock_tap.c
diff --git a/net/vmw_vsock/Makefile b/net/vmw_vsock/Makefile
index bc27c70..09fc2eb 100644
--- a/net/vmw_vsock/Makefile
+++ b/net/vmw_vsock/Makefile
@@ -3,7 +3,7 @@ obj-$(CONFIG_VMWARE_VMCI_VSOCKETS) += vmw_vsock_vmci_transport.o
obj-$(CONFIG_VIRTIO_VSOCKETS) += vmw_vsock_virtio_transport.o
obj-$(CONFIG_VIRTIO_VSOCKETS_COMMON) += vmw_vsock_virtio_transport_common.o
-vsock-y += af_vsock.o vsock_addr.o
+vsock-y += af_vsock.o af_vsock_tap.o vsock_addr.o
vmw_vsock_vmci_transport-y += vmci_transport.o vmci_transport_notify.o \
vmci_transport_notify_qstate.o
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index f32ed9a..c526d4f 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -188,4 +188,17 @@ struct sock *vsock_find_connected_socket(struct
sockaddr_vm *src,
void vsock_remove_sock(struct vsock_sock *vsk);
void vsock_for_each_connected_socket(void (*fn)(struct sock *sk));
+/**** TAP ****/
+
+struct vsock_tap {
+ struct net_device *dev;
+ struct module *module;
+ struct list_head list;
+};
+
+int vsock_init_tap(void);
+int vsock_add_tap(struct vsock_tap *vt);
+int vsock_remove_tap(struct vsock_tap *vt);
+void vsock_deliver_tap(struct sk_buff *skb);
+
#endif /* __AF_VSOCK_H__ */
diff --git a/include/uapi/linux/if_arp.h b/include/uapi/linux/if_arp.h
index 4d024d7..cf73510 100644
--- a/include/uapi/linux/if_arp.h
+++ b/include/uapi/linux/if_arp.h
@@ -95,6 +95,7 @@
#define ARPHRD_IP6GRE 823 /* GRE over IPv6 */
#define ARPHRD_NETLINK 824 /* Netlink header */
#define ARPHRD_6LOWPAN 825 /* IPv6 over LoWPAN */
+#define ARPHRD_VSOCKMON 826 /* Vsock monitor header
*/
#define ARPHRD_VOID 0xFFFF /* Void type, nothing is known */
#define ARPHRD_NONE 0xFFFE /* zero header length */
diff --git a/net/vmw_vsock/af_vsock_tap.c b/net/vmw_vsock/af_vsock_tap.c
new file mode 100644
index 0000000..db0c4e7
--- /dev/null
+++ b/net/vmw_vsock/af_vsock_tap.c
@@ -0,0 +1,107 @@
+/*
+ * 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;
+ }
+
+ consume_skb(skb);
+}
+
+void vsock_deliver_tap(struct sk_buff *skb)
+{
+ rcu_read_lock();
+
+ if (unlikely(!list_empty(&vsock_tap_all)))
+ __vsock_deliver_tap(skb);
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(vsock_deliver_tap);
--
2.9.3
