linux-stable/net/vmw_vsock/af_vsock_tap.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

110 lines
2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Tap functions for AF_VSOCK sockets.
*
* Code based on net/netlink/af_netlink.c tap functions.
*/
#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);