linux_old1/net/decnet/dn_neigh.c

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/*
* DECnet An implementation of the DECnet protocol suite for the LINUX
* operating system. DECnet is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* DECnet Neighbour Functions (Adjacency Database and
* On-Ethernet Cache)
*
* Author: Steve Whitehouse <SteveW@ACM.org>
*
*
* Changes:
* Steve Whitehouse : Fixed router listing routine
* Steve Whitehouse : Added error_report functions
* Steve Whitehouse : Added default router detection
* Steve Whitehouse : Hop counts in outgoing messages
* Steve Whitehouse : Fixed src/dst in outgoing messages so
* forwarding now stands a good chance of
* working.
* Steve Whitehouse : Fixed neighbour states (for now anyway).
* Steve Whitehouse : Made error_report functions dummies. This
* is not the right place to return skbs.
* Steve Whitehouse : Convert to seq_file
*
*/
#include <linux/net.h>
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/if_arp.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/string.h>
#include <linux/netfilter_decnet.h>
#include <linux/spinlock.h>
#include <linux/seq_file.h>
#include <linux/rcupdate.h>
#include <linux/jhash.h>
#include <asm/atomic.h>
#include <net/net_namespace.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/dn.h>
#include <net/dn_dev.h>
#include <net/dn_neigh.h>
#include <net/dn_route.h>
static int dn_neigh_construct(struct neighbour *);
static void dn_long_error_report(struct neighbour *, struct sk_buff *);
static void dn_short_error_report(struct neighbour *, struct sk_buff *);
static int dn_long_output(struct neighbour *, struct sk_buff *);
static int dn_short_output(struct neighbour *, struct sk_buff *);
static int dn_phase3_output(struct neighbour *, struct sk_buff *);
/*
* For talking to broadcast devices: Ethernet & PPP
*/
static const struct neigh_ops dn_long_ops = {
.family = AF_DECnet,
.error_report = dn_long_error_report,
.output = dn_long_output,
.connected_output = dn_long_output,
};
/*
* For talking to pointopoint and multidrop devices: DDCMP and X.25
*/
static const struct neigh_ops dn_short_ops = {
.family = AF_DECnet,
.error_report = dn_short_error_report,
.output = dn_short_output,
.connected_output = dn_short_output,
};
/*
* For talking to DECnet phase III nodes
*/
static const struct neigh_ops dn_phase3_ops = {
.family = AF_DECnet,
.error_report = dn_short_error_report, /* Can use short version here */
.output = dn_phase3_output,
.connected_output = dn_phase3_output,
};
static u32 dn_neigh_hash(const void *pkey,
const struct net_device *dev,
__u32 hash_rnd)
{
return jhash_2words(*(__u16 *)pkey, 0, hash_rnd);
}
struct neigh_table dn_neigh_table = {
.family = PF_DECnet,
.entry_size = sizeof(struct dn_neigh),
.key_len = sizeof(__le16),
.hash = dn_neigh_hash,
.constructor = dn_neigh_construct,
.id = "dn_neigh_cache",
.parms ={
.tbl = &dn_neigh_table,
.base_reachable_time = 30 * HZ,
.retrans_time = 1 * HZ,
.gc_staletime = 60 * HZ,
.reachable_time = 30 * HZ,
.delay_probe_time = 5 * HZ,
.queue_len = 3,
.ucast_probes = 0,
.app_probes = 0,
.mcast_probes = 0,
.anycast_delay = 0,
.proxy_delay = 0,
.proxy_qlen = 0,
.locktime = 1 * HZ,
},
.gc_interval = 30 * HZ,
.gc_thresh1 = 128,
.gc_thresh2 = 512,
.gc_thresh3 = 1024,
};
static int dn_neigh_construct(struct neighbour *neigh)
{
struct net_device *dev = neigh->dev;
struct dn_neigh *dn = (struct dn_neigh *)neigh;
struct dn_dev *dn_db;
struct neigh_parms *parms;
rcu_read_lock();
dn_db = rcu_dereference(dev->dn_ptr);
if (dn_db == NULL) {
rcu_read_unlock();
return -EINVAL;
}
parms = dn_db->neigh_parms;
if (!parms) {
rcu_read_unlock();
return -EINVAL;
}
__neigh_parms_put(neigh->parms);
neigh->parms = neigh_parms_clone(parms);
if (dn_db->use_long)
neigh->ops = &dn_long_ops;
else
neigh->ops = &dn_short_ops;
rcu_read_unlock();
if (dn->flags & DN_NDFLAG_P3)
neigh->ops = &dn_phase3_ops;
neigh->nud_state = NUD_NOARP;
neigh->output = neigh->ops->connected_output;
if ((dev->type == ARPHRD_IPGRE) || (dev->flags & IFF_POINTOPOINT))
memcpy(neigh->ha, dev->broadcast, dev->addr_len);
else if ((dev->type == ARPHRD_ETHER) || (dev->type == ARPHRD_LOOPBACK))
dn_dn2eth(neigh->ha, dn->addr);
else {
if (net_ratelimit())
printk(KERN_DEBUG "Trying to create neigh for hw %d\n", dev->type);
return -EINVAL;
}
/*
* Make an estimate of the remote block size by assuming that its
* two less then the device mtu, which it true for ethernet (and
* other things which support long format headers) since there is
* an extra length field (of 16 bits) which isn't part of the
* ethernet headers and which the DECnet specs won't admit is part
* of the DECnet routing headers either.
*
* If we over estimate here its no big deal, the NSP negotiations
* will prevent us from sending packets which are too large for the
* remote node to handle. In any case this figure is normally updated
* by a hello message in most cases.
*/
dn->blksize = dev->mtu - 2;
return 0;
}
static void dn_long_error_report(struct neighbour *neigh, struct sk_buff *skb)
{
printk(KERN_DEBUG "dn_long_error_report: called\n");
kfree_skb(skb);
}
static void dn_short_error_report(struct neighbour *neigh, struct sk_buff *skb)
{
printk(KERN_DEBUG "dn_short_error_report: called\n");
kfree_skb(skb);
}
static int dn_neigh_output_packet(struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct dn_route *rt = (struct dn_route *)dst;
struct neighbour *neigh = dst->neighbour;
struct net_device *dev = neigh->dev;
char mac_addr[ETH_ALEN];
dn_dn2eth(mac_addr, rt->rt_local_src);
if (dev_hard_header(skb, dev, ntohs(skb->protocol), neigh->ha,
mac_addr, skb->len) >= 0)
return dev_queue_xmit(skb);
if (net_ratelimit())
printk(KERN_DEBUG "dn_neigh_output_packet: oops, can't send packet\n");
kfree_skb(skb);
return -EINVAL;
}
static int dn_long_output(struct neighbour *neigh, struct sk_buff *skb)
{
struct net_device *dev = neigh->dev;
int headroom = dev->hard_header_len + sizeof(struct dn_long_packet) + 3;
unsigned char *data;
struct dn_long_packet *lp;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
if (skb_headroom(skb) < headroom) {
struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
if (skb2 == NULL) {
if (net_ratelimit())
printk(KERN_CRIT "dn_long_output: no memory\n");
kfree_skb(skb);
return -ENOBUFS;
}
kfree_skb(skb);
skb = skb2;
if (net_ratelimit())
printk(KERN_INFO "dn_long_output: Increasing headroom\n");
}
data = skb_push(skb, sizeof(struct dn_long_packet) + 3);
lp = (struct dn_long_packet *)(data+3);
*((__le16 *)data) = cpu_to_le16(skb->len - 2);
*(data + 2) = 1 | DN_RT_F_PF; /* Padding */
lp->msgflg = DN_RT_PKT_LONG|(cb->rt_flags&(DN_RT_F_IE|DN_RT_F_RQR|DN_RT_F_RTS));
lp->d_area = lp->d_subarea = 0;
dn_dn2eth(lp->d_id, cb->dst);
lp->s_area = lp->s_subarea = 0;
dn_dn2eth(lp->s_id, cb->src);
lp->nl2 = 0;
lp->visit_ct = cb->hops & 0x3f;
lp->s_class = 0;
lp->pt = 0;
skb_reset_network_header(skb);
return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
neigh->dev, dn_neigh_output_packet);
}
static int dn_short_output(struct neighbour *neigh, struct sk_buff *skb)
{
struct net_device *dev = neigh->dev;
int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
struct dn_short_packet *sp;
unsigned char *data;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
if (skb_headroom(skb) < headroom) {
struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
if (skb2 == NULL) {
if (net_ratelimit())
printk(KERN_CRIT "dn_short_output: no memory\n");
kfree_skb(skb);
return -ENOBUFS;
}
kfree_skb(skb);
skb = skb2;
if (net_ratelimit())
printk(KERN_INFO "dn_short_output: Increasing headroom\n");
}
data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
*((__le16 *)data) = cpu_to_le16(skb->len - 2);
sp = (struct dn_short_packet *)(data+2);
sp->msgflg = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
sp->dstnode = cb->dst;
sp->srcnode = cb->src;
sp->forward = cb->hops & 0x3f;
skb_reset_network_header(skb);
return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
neigh->dev, dn_neigh_output_packet);
}
/*
* Phase 3 output is the same is short output, execpt that
* it clears the area bits before transmission.
*/
static int dn_phase3_output(struct neighbour *neigh, struct sk_buff *skb)
{
struct net_device *dev = neigh->dev;
int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
struct dn_short_packet *sp;
unsigned char *data;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
if (skb_headroom(skb) < headroom) {
struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
if (skb2 == NULL) {
if (net_ratelimit())
printk(KERN_CRIT "dn_phase3_output: no memory\n");
kfree_skb(skb);
return -ENOBUFS;
}
kfree_skb(skb);
skb = skb2;
if (net_ratelimit())
printk(KERN_INFO "dn_phase3_output: Increasing headroom\n");
}
data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
*((__le16 *)data) = cpu_to_le16(skb->len - 2);
sp = (struct dn_short_packet *)(data + 2);
sp->msgflg = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
sp->dstnode = cb->dst & cpu_to_le16(0x03ff);
sp->srcnode = cb->src & cpu_to_le16(0x03ff);
sp->forward = cb->hops & 0x3f;
skb_reset_network_header(skb);
return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
neigh->dev, dn_neigh_output_packet);
}
/*
* Unfortunately, the neighbour code uses the device in its hash
* function, so we don't get any advantage from it. This function
* basically does a neigh_lookup(), but without comparing the device
* field. This is required for the On-Ethernet cache
*/
/*
* Pointopoint link receives a hello message
*/
void dn_neigh_pointopoint_hello(struct sk_buff *skb)
{
kfree_skb(skb);
}
/*
* Ethernet router hello message received
*/
int dn_neigh_router_hello(struct sk_buff *skb)
{
struct rtnode_hello_message *msg = (struct rtnode_hello_message *)skb->data;
struct neighbour *neigh;
struct dn_neigh *dn;
struct dn_dev *dn_db;
__le16 src;
src = dn_eth2dn(msg->id);
neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
dn = (struct dn_neigh *)neigh;
if (neigh) {
write_lock(&neigh->lock);
neigh->used = jiffies;
dn_db = rcu_dereference(neigh->dev->dn_ptr);
if (!(neigh->nud_state & NUD_PERMANENT)) {
neigh->updated = jiffies;
if (neigh->dev->type == ARPHRD_ETHER)
memcpy(neigh->ha, &eth_hdr(skb)->h_source, ETH_ALEN);
dn->blksize = le16_to_cpu(msg->blksize);
dn->priority = msg->priority;
dn->flags &= ~DN_NDFLAG_P3;
switch (msg->iinfo & DN_RT_INFO_TYPE) {
case DN_RT_INFO_L1RT:
dn->flags &=~DN_NDFLAG_R2;
dn->flags |= DN_NDFLAG_R1;
break;
case DN_RT_INFO_L2RT:
dn->flags |= DN_NDFLAG_R2;
}
}
/* Only use routers in our area */
if ((le16_to_cpu(src)>>10) == (le16_to_cpu((decnet_address))>>10)) {
if (!dn_db->router) {
dn_db->router = neigh_clone(neigh);
} else {
if (msg->priority > ((struct dn_neigh *)dn_db->router)->priority)
neigh_release(xchg(&dn_db->router, neigh_clone(neigh)));
}
}
write_unlock(&neigh->lock);
neigh_release(neigh);
}
kfree_skb(skb);
return 0;
}
/*
* Endnode hello message received
*/
int dn_neigh_endnode_hello(struct sk_buff *skb)
{
struct endnode_hello_message *msg = (struct endnode_hello_message *)skb->data;
struct neighbour *neigh;
struct dn_neigh *dn;
__le16 src;
src = dn_eth2dn(msg->id);
neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
dn = (struct dn_neigh *)neigh;
if (neigh) {
write_lock(&neigh->lock);
neigh->used = jiffies;
if (!(neigh->nud_state & NUD_PERMANENT)) {
neigh->updated = jiffies;
if (neigh->dev->type == ARPHRD_ETHER)
memcpy(neigh->ha, &eth_hdr(skb)->h_source, ETH_ALEN);
dn->flags &= ~(DN_NDFLAG_R1 | DN_NDFLAG_R2);
dn->blksize = le16_to_cpu(msg->blksize);
dn->priority = 0;
}
write_unlock(&neigh->lock);
neigh_release(neigh);
}
kfree_skb(skb);
return 0;
}
static char *dn_find_slot(char *base, int max, int priority)
{
int i;
unsigned char *min = NULL;
base += 6; /* skip first id */
for(i = 0; i < max; i++) {
if (!min || (*base < *min))
min = base;
base += 7; /* find next priority */
}
if (!min)
return NULL;
return (*min < priority) ? (min - 6) : NULL;
}
struct elist_cb_state {
struct net_device *dev;
unsigned char *ptr;
unsigned char *rs;
int t, n;
};
static void neigh_elist_cb(struct neighbour *neigh, void *_info)
{
struct elist_cb_state *s = _info;
struct dn_neigh *dn;
if (neigh->dev != s->dev)
return;
dn = (struct dn_neigh *) neigh;
if (!(dn->flags & (DN_NDFLAG_R1|DN_NDFLAG_R2)))
return;
if (s->t == s->n)
s->rs = dn_find_slot(s->ptr, s->n, dn->priority);
else
s->t++;
if (s->rs == NULL)
return;
dn_dn2eth(s->rs, dn->addr);
s->rs += 6;
*(s->rs) = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
*(s->rs) |= dn->priority;
s->rs++;
}
int dn_neigh_elist(struct net_device *dev, unsigned char *ptr, int n)
{
struct elist_cb_state state;
state.dev = dev;
state.t = 0;
state.n = n;
state.ptr = ptr;
state.rs = ptr;
neigh_for_each(&dn_neigh_table, neigh_elist_cb, &state);
return state.t;
}
#ifdef CONFIG_PROC_FS
static inline void dn_neigh_format_entry(struct seq_file *seq,
struct neighbour *n)
{
struct dn_neigh *dn = (struct dn_neigh *) n;
char buf[DN_ASCBUF_LEN];
read_lock(&n->lock);
seq_printf(seq, "%-7s %s%s%s %02x %02d %07ld %-8s\n",
dn_addr2asc(le16_to_cpu(dn->addr), buf),
(dn->flags&DN_NDFLAG_R1) ? "1" : "-",
(dn->flags&DN_NDFLAG_R2) ? "2" : "-",
(dn->flags&DN_NDFLAG_P3) ? "3" : "-",
dn->n.nud_state,
atomic_read(&dn->n.refcnt),
dn->blksize,
(dn->n.dev) ? dn->n.dev->name : "?");
read_unlock(&n->lock);
}
static int dn_neigh_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "Addr Flags State Use Blksize Dev\n");
} else {
dn_neigh_format_entry(seq, v);
}
return 0;
}
static void *dn_neigh_seq_start(struct seq_file *seq, loff_t *pos)
{
return neigh_seq_start(seq, pos, &dn_neigh_table,
NEIGH_SEQ_NEIGH_ONLY);
}
static const struct seq_operations dn_neigh_seq_ops = {
.start = dn_neigh_seq_start,
.next = neigh_seq_next,
.stop = neigh_seq_stop,
.show = dn_neigh_seq_show,
};
static int dn_neigh_seq_open(struct inode *inode, struct file *file)
{
[NETNS]: Modify the neighbour table code so it handles multiple network namespaces I'm actually surprised at how much was involved. At first glance it appears that the neighbour table data structures are already split by network device so all that should be needed is to modify the user interface commands to filter the set of neighbours by the network namespace of their devices. However a couple things turned up while I was reading through the code. The proxy neighbour table allows entries with no network device, and the neighbour parms are per network device (except for the defaults) so they now need a per network namespace default. So I updated the two structures (which surprised me) with their very own network namespace parameter. Updated the relevant lookup and destroy routines with a network namespace parameter and modified the code that interacts with users to filter out neighbour table entries for devices of other namespaces. I'm a little concerned that we can modify and display the global table configuration and from all network namespaces. But this appears good enough for now. I keep thinking modifying the neighbour table to have per network namespace instances of each table type would should be cleaner. The hash table is already dynamically sized so there are it is not a limiter. The default parameter would be straight forward to take care of. However when I look at the how the network table is built and used I still find some assumptions that there is only a single neighbour table for each type of table in the kernel. The netlink operations, neigh_seq_start, the non-core network users that call neigh_lookup. So while it might be doable it would require more refactoring than my current approach of just doing a little extra filtering in the code. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-24 16:13:18 +08:00
return seq_open_net(inode, file, &dn_neigh_seq_ops,
sizeof(struct neigh_seq_state));
}
static const struct file_operations dn_neigh_seq_fops = {
.owner = THIS_MODULE,
.open = dn_neigh_seq_open,
.read = seq_read,
.llseek = seq_lseek,
[NETNS]: Modify the neighbour table code so it handles multiple network namespaces I'm actually surprised at how much was involved. At first glance it appears that the neighbour table data structures are already split by network device so all that should be needed is to modify the user interface commands to filter the set of neighbours by the network namespace of their devices. However a couple things turned up while I was reading through the code. The proxy neighbour table allows entries with no network device, and the neighbour parms are per network device (except for the defaults) so they now need a per network namespace default. So I updated the two structures (which surprised me) with their very own network namespace parameter. Updated the relevant lookup and destroy routines with a network namespace parameter and modified the code that interacts with users to filter out neighbour table entries for devices of other namespaces. I'm a little concerned that we can modify and display the global table configuration and from all network namespaces. But this appears good enough for now. I keep thinking modifying the neighbour table to have per network namespace instances of each table type would should be cleaner. The hash table is already dynamically sized so there are it is not a limiter. The default parameter would be straight forward to take care of. However when I look at the how the network table is built and used I still find some assumptions that there is only a single neighbour table for each type of table in the kernel. The netlink operations, neigh_seq_start, the non-core network users that call neigh_lookup. So while it might be doable it would require more refactoring than my current approach of just doing a little extra filtering in the code. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-24 16:13:18 +08:00
.release = seq_release_net,
};
#endif
void __init dn_neigh_init(void)
{
neigh_table_init(&dn_neigh_table);
proc_net_fops_create(&init_net, "decnet_neigh", S_IRUGO, &dn_neigh_seq_fops);
}
void __exit dn_neigh_cleanup(void)
{
proc_net_remove(&init_net, "decnet_neigh");
neigh_table_clear(&dn_neigh_table);
}