linux/net/802/stp.c
Paul Gortmaker 3a9a231d97 net: Fix files explicitly needing to include module.h
With calls to modular infrastructure, these files really
needs the full module.h header.  Call it out so some of the
cleanups of implicit and unrequired includes elsewhere can be
cleaned up.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:28 -04:00

105 lines
2.6 KiB
C

/*
* STP SAP demux
*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/mutex.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/llc.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <net/llc.h>
#include <net/llc_pdu.h>
#include <net/stp.h>
/* 01:80:c2:00:00:20 - 01:80:c2:00:00:2F */
#define GARP_ADDR_MIN 0x20
#define GARP_ADDR_MAX 0x2F
#define GARP_ADDR_RANGE (GARP_ADDR_MAX - GARP_ADDR_MIN)
static const struct stp_proto __rcu *garp_protos[GARP_ADDR_RANGE + 1] __read_mostly;
static const struct stp_proto __rcu *stp_proto __read_mostly;
static struct llc_sap *sap __read_mostly;
static unsigned int sap_registered;
static DEFINE_MUTEX(stp_proto_mutex);
/* Called under rcu_read_lock from LLC */
static int stp_pdu_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
const struct ethhdr *eh = eth_hdr(skb);
const struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
const struct stp_proto *proto;
if (pdu->ssap != LLC_SAP_BSPAN ||
pdu->dsap != LLC_SAP_BSPAN ||
pdu->ctrl_1 != LLC_PDU_TYPE_U)
goto err;
if (eh->h_dest[5] >= GARP_ADDR_MIN && eh->h_dest[5] <= GARP_ADDR_MAX) {
proto = rcu_dereference(garp_protos[eh->h_dest[5] -
GARP_ADDR_MIN]);
if (proto &&
compare_ether_addr(eh->h_dest, proto->group_address))
goto err;
} else
proto = rcu_dereference(stp_proto);
if (!proto)
goto err;
proto->rcv(proto, skb, dev);
return 0;
err:
kfree_skb(skb);
return 0;
}
int stp_proto_register(const struct stp_proto *proto)
{
int err = 0;
mutex_lock(&stp_proto_mutex);
if (sap_registered++ == 0) {
sap = llc_sap_open(LLC_SAP_BSPAN, stp_pdu_rcv);
if (!sap) {
err = -ENOMEM;
goto out;
}
}
if (is_zero_ether_addr(proto->group_address))
rcu_assign_pointer(stp_proto, proto);
else
rcu_assign_pointer(garp_protos[proto->group_address[5] -
GARP_ADDR_MIN], proto);
out:
mutex_unlock(&stp_proto_mutex);
return err;
}
EXPORT_SYMBOL_GPL(stp_proto_register);
void stp_proto_unregister(const struct stp_proto *proto)
{
mutex_lock(&stp_proto_mutex);
if (is_zero_ether_addr(proto->group_address))
RCU_INIT_POINTER(stp_proto, NULL);
else
RCU_INIT_POINTER(garp_protos[proto->group_address[5] -
GARP_ADDR_MIN], NULL);
synchronize_rcu();
if (--sap_registered == 0)
llc_sap_put(sap);
mutex_unlock(&stp_proto_mutex);
}
EXPORT_SYMBOL_GPL(stp_proto_unregister);
MODULE_LICENSE("GPL");