dn_table.c
/*
* 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 Routing Forwarding Information Base (Routing Tables)
*
* Author: Steve Whitehouse <SteveW@ACM.org>
* Mostly copied from the IPv4 routing code
*
*
* Changes:
*
*/
#include <linux/string.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <linux/slab.h>
#include <linux/sockios.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <asm/uaccess.h>
#include <linux/route.h> /* RTF_xxx */
#include <net/neighbour.h>
#include <net/netlink.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/dn.h>
#include <net/dn_route.h>
#include <net/dn_fib.h>
#include <net/dn_neigh.h>
#include <net/dn_dev.h>
struct dn_zone
{
struct dn_zone *dz_next;
struct dn_fib_node **dz_hash;
int dz_nent;
int dz_divisor;
u32 dz_hashmask;
#define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
int dz_order;
__le16 dz_mask;
#define DZ_MASK(dz) ((dz)->dz_mask)
};
struct dn_hash
{
struct dn_zone *dh_zones[17];
struct dn_zone *dh_zone_list;
};
#define dz_key_0(key) ((key).datum = 0)
#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
#define endfor_nexthops(fi) }
#define DN_MAX_DIVISOR 1024
#define DN_S_ZOMBIE 1
#define DN_S_ACCESSED 2
#define DN_FIB_SCAN(f, fp) \
for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
#define DN_FIB_SCAN_KEY(f, fp, key) \
for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
#define RT_TABLE_MIN 1
#define DN_FIB_TABLE_HASHSZ 256
static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ];
static DEFINE_RWLOCK(dn_fib_tables_lock);
static struct kmem_cache *dn_hash_kmem __read_mostly;
static int dn_fib_hash_zombies;
static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
{
u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order);
h ^= (h >> 10);
h ^= (h >> 6);
h &= DZ_HASHMASK(dz);
return *(dn_fib_idx_t *)&h;
}
static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz)
{
dn_fib_key_t k;
k.datum = dst & DZ_MASK(dz);
return k;
}
static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
{
return &dz->dz_hash[dn_hash(key, dz).datum];
}
static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
{
return dz->dz_hash[dn_hash(key, dz).datum];
}
static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
{
return a.datum == b.datum;
}
static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
{
return a.datum <= b.datum;
}
static inline void dn_rebuild_zone(struct dn_zone *dz,
struct dn_fib_node **old_ht,
int old_divisor)
{
struct dn_fib_node *f, **fp, *next;
int i;
for(i = 0; i < old_divisor; i++) {
for(f = old_ht[i]; f; f = next) {
next = f->fn_next;
for(fp = dn_chain_p(f->fn_key, dz);
*fp && dn_key_leq((*fp)->fn_key, f->fn_key);
fp = &(*fp)->fn_next)
/* NOTHING */;
f->fn_next = *fp;
*fp = f;
}
}
}
static void dn_rehash_zone(struct dn_zone *dz)
{
struct dn_fib_node **ht, **old_ht;
int old_divisor, new_divisor;
u32 new_hashmask;
old_divisor = dz->dz_divisor;
switch (old_divisor) {
case 16:
new_divisor = 256;
new_hashmask = 0xFF;
break;
default:
printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n",
old_divisor);
case 256:
new_divisor = 1024;
new_hashmask = 0x3FF;
break;
}
ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL);
if (ht == NULL)
return;
write_lock_bh(&dn_fib_tables_lock);
old_ht = dz->dz_hash;
dz->dz_hash = ht;
dz->dz_hashmask = new_hashmask;
dz->dz_divisor = new_divisor;
dn_rebuild_zone(dz, old_ht, old_divisor);
write_unlock_bh(&dn_fib_tables_lock);
kfree(old_ht);
}
static void dn_free_node(struct dn_fib_node *f)
{
dn_fib_release_info(DN_FIB_INFO(f));
kmem_cache_free(dn_hash_kmem, f);
}
static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
{
int i;
struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL);
if (!dz)
return NULL;
if (z) {
dz->dz_divisor = 16;
dz->dz_hashmask = 0x0F;
} else {
dz->dz_divisor = 1;
dz->dz_hashmask = 0;
}
dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL);
if (!dz->dz_hash) {
kfree(dz);
return NULL;
}
dz->dz_order = z;
dz->dz_mask = dnet_make_mask(z);
for(i = z + 1; i <= 16; i++)
if (table->dh_zones[i])
break;
write_lock_bh(&dn_fib_tables_lock);
if (i>16) {
dz->dz_next = table->dh_zone_list;
table->dh_zone_list = dz;
} else {
dz->dz_next = table->dh_zones[i]->dz_next;
table->dh_zones[i]->dz_next = dz;
}
table->dh_zones[z] = dz;
write_unlock_bh(&dn_fib_tables_lock);
return dz;
}
static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
{
struct rtnexthop *nhp;
int nhlen;
if (attrs[RTA_PRIORITY] &&
nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
return 1;
if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
(!attrs[RTA_GATEWAY] || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
return 0;
return 1;
}
if (!attrs[RTA_MULTIPATH])
return 0;
nhp = nla_data(attrs[RTA_MULTIPATH]);
nhlen = nla_len(attrs[RTA_MULTIPATH]);
for_nexthops(fi) {
int attrlen = nhlen - sizeof(struct rtnexthop);
__le16 gw;
if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
return -EINVAL;
if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
return 1;
if (attrlen) {
struct nlattr *gw_attr;
gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
gw = gw_attr ? nla_get_le16(gw_attr) : 0;
if (gw && gw != nh->nh_gw)
return 1;
}
nhp = RTNH_NEXT(nhp);
} endfor_nexthops(fi);
return 0;
}
static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi)
{
size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
+ nla_total_size(4) /* RTA_TABLE */
+ nla_total_size(2) /* RTA_DST */
+ nla_total_size(4); /* RTA_PRIORITY */
/* space for nested metrics */
payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
if (fi->fib_nhs) {
/* Also handles the special case fib_nhs == 1 */
/* each nexthop is packed in an attribute */
size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
/* may contain a gateway attribute */
nhsize += nla_total_size(4);
/* all nexthops are packed in a nested attribute */
payload += nla_total_size(fi->fib_nhs * nhsize);
}
return payload;
}
static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
u32 tb_id, u8 type, u8 scope, void *dst, int dst_len,
struct dn_fib_info *fi, unsigned int flags)
{
struct rtmsg *rtm;
struct nlmsghdr *nlh;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
if (!nlh)
return -EMSGSIZE;
rtm = nlmsg_data(nlh);
rtm->rtm_family = AF_DECnet;
rtm->rtm_dst_len = dst_len;
rtm->rtm_src_len = 0;
rtm->rtm_tos = 0;
rtm->rtm_table = tb_id;
rtm->rtm_flags = fi->fib_flags;
rtm->rtm_scope = scope;
rtm->rtm_type = type;
rtm->rtm_protocol = fi->fib_protocol;
if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0)
goto errout;
if (rtm->rtm_dst_len &&
nla_put(skb, RTA_DST, 2, dst) < 0)
goto errout;
if (fi->fib_priority &&
nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0)
goto errout;
if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
goto errout;
if (fi->fib_nhs == 1) {
if (fi->fib_nh->nh_gw &&
nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0)
goto errout;
if (fi->fib_nh->nh_oif &&
nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif) < 0)
goto errout;
}
if (fi->fib_nhs > 1) {
struct rtnexthop *nhp;
struct nlattr *mp_head;
if (!(mp_head = nla_nest_start(skb, RTA_MULTIPATH)))
goto errout;
for_nexthops(fi) {
if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp))))
goto errout;
nhp->rtnh_flags = nh->nh_flags & 0xFF;
nhp->rtnh_hops = nh->nh_weight - 1;
nhp->rtnh_ifindex = nh->nh_oif;
if (nh->nh_gw &&
nla_put_le16(skb, RTA_GATEWAY, nh->nh_gw) < 0)
goto errout;
nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
} endfor_nexthops(fi);
nla_nest_end(skb, mp_head);
}
return nlmsg_end(skb, nlh);
errout:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id,
struct nlmsghdr *nlh, struct netlink_skb_parms *req)
{
struct sk_buff *skb;
u32 portid = req ? req->portid : 0;
int err = -ENOBUFS;
skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f)), GFP_KERNEL);
if (skb == NULL)
goto errout;
err = dn_fib_dump_info(skb, portid, nlh->nlmsg_seq, event, tb_id,
f->fn_type, f->fn_scope, &f->fn_key, z,
DN_FIB_INFO(f), 0);
if (err < 0) {
/* -EMSGSIZE implies BUG in dn_fib_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, &init_net, portid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL);
return;
errout:
if (err < 0)
rtnl_set_sk_err(&init_net, RTNLGRP_DECnet_ROUTE, err);
}
static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
struct netlink_callback *cb,
struct dn_fib_table *tb,
struct dn_zone *dz,
struct dn_fib_node *f)
{
int i, s_i;
s_i = cb->args[4];
for(i = 0; f; i++, f = f->fn_next) {
if (i < s_i)
continue;
if (f->fn_state & DN_S_ZOMBIE)
continue;
if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
RTM_NEWROUTE,
tb->n,
(f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
f->fn_scope, &f->fn_key, dz->dz_order,
f->fn_info, NLM_F_MULTI) < 0) {
cb->args[4] = i;
return -1;
}
}
cb->args[4] = i;
return skb->len;
}
static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
struct netlink_callback *cb,
struct dn_fib_table *tb,
struct dn_zone *dz)
{
int h, s_h;
s_h = cb->args[3];
for(h = 0; h < dz->dz_divisor; h++) {
if (h < s_h)
continue;
if (h > s_h)
memset(&cb->args[4], 0, sizeof(cb->args) - 4*sizeof(cb->args[0]));
if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
continue;
if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
cb->args[3] = h;
return -1;
}
}
cb->args[3] = h;
return skb->len;
}
static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
struct netlink_callback *cb)
{
int m, s_m;
struct dn_zone *dz;
struct dn_hash *table = (struct dn_hash *)tb->data;
s_m = cb->args[2];
read_lock(&dn_fib_tables_lock);
for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
if (m < s_m)
continue;
if (m > s_m)
memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
cb->args[2] = m;
read_unlock(&dn_fib_tables_lock);
return -1;
}
}
read_unlock(&dn_fib_tables_lock);
cb->args[2] = m;
return skb->len;
}
int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
unsigned int h, s_h;
unsigned int e = 0, s_e;
struct dn_fib_table *tb;
int dumped = 0;
if (!net_eq(net, &init_net))
return 0;
if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
((struct rtmsg *)nlmsg_data(cb->nlh))->rtm_flags&RTM_F_CLONED)
return dn_cache_dump(skb, cb);
s_h = cb->args[0];
s_e = cb->args[1];
for (h = s_h; h < DN_FIB_TABLE_HASHSZ; h++, s_h = 0) {
e = 0;
hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist) {
if (e < s_e)
goto next;
if (dumped)
memset(&cb->args[2], 0, sizeof(cb->args) -
2 * sizeof(cb->args[0]));
if (tb->dump(tb, skb, cb) < 0)
goto out;
dumped = 1;
next:
e++;
}
}
out:
cb->args[1] = e;
cb->args[0] = h;
return skb->len;
}
static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
struct nlmsghdr *n, struct netlink_skb_parms *req)
{
struct dn_hash *table = (struct dn_hash *)tb->data;
struct dn_fib_node *new_f, *f, **fp, **del_fp;
struct dn_zone *dz;
struct dn_fib_info *fi;
int z = r->rtm_dst_len;
int type = r->rtm_type;
dn_fib_key_t key;
int err;
if (z > 16)
return -EINVAL;
dz = table->dh_zones[z];
if (!dz && !(dz = dn_new_zone(table, z)))
return -ENOBUFS;
dz_key_0(key);
if (attrs[RTA_DST]) {
__le16 dst = nla_get_le16(attrs[RTA_DST]);
if (dst & ~DZ_MASK(dz))
return -EINVAL;
key = dz_key(dst, dz);
}
if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL)
return err;
if (dz->dz_nent > (dz->dz_divisor << 2) &&
dz->dz_divisor > DN_MAX_DIVISOR &&
(z==16 || (1<<z) > dz->dz_divisor))
dn_rehash_zone(dz);
fp = dn_chain_p(key, dz);
DN_FIB_SCAN(f, fp) {
if (dn_key_leq(key, f->fn_key))
break;
}
del_fp = NULL;
if (f && (f->fn_state & DN_S_ZOMBIE) &&
dn_key_eq(f->fn_key, key)) {
del_fp = fp;
fp = &f->fn_next;
f = *fp;
goto create;
}
DN_FIB_SCAN_KEY(f, fp, key) {
if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
break;
}
if (f && dn_key_eq(f->fn_key, key) &&
fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
struct dn_fib_node **ins_fp;
err = -EEXIST;
if (n->nlmsg_flags & NLM_F_EXCL)
goto out;
if (n->nlmsg_flags & NLM_F_REPLACE) {
del_fp = fp;
fp = &f->fn_next;
f = *fp;
goto replace;
}
ins_fp = fp;
err = -EEXIST;
DN_FIB_SCAN_KEY(f, fp, key) {
if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
break;
if (f->fn_type == type &&
f->fn_scope == r->rtm_scope &&
DN_FIB_INFO(f) == fi)
goto out;
}
if (!(n->nlmsg_flags & NLM_F_APPEND)) {
fp = ins_fp;
f = *fp;
}
}
create:
err = -ENOENT;
if (!(n->nlmsg_flags & NLM_F_CREATE))
goto out;
replace:
err = -ENOBUFS;
new_f = kmem_cache_zalloc(dn_hash_kmem, GFP_KERNEL);
if (new_f == NULL)
goto out;
new_f->fn_key = key;
new_f->fn_type = type;
new_f->fn_scope = r->rtm_scope;
DN_FIB_INFO(new_f) = fi;
new_f->fn_next = f;
write_lock_bh(&dn_fib_tables_lock);
*fp = new_f;
write_unlock_bh(&dn_fib_tables_lock);
dz->dz_nent++;
if (del_fp) {
f = *del_fp;
write_lock_bh(&dn_fib_tables_lock);
*del_fp = f->fn_next;
write_unlock_bh(&dn_fib_tables_lock);
if (!(f->fn_state & DN_S_ZOMBIE))
dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
if (f->fn_state & DN_S_ACCESSED)
dn_rt_cache_flush(-1);
dn_free_node(f);
dz->dz_nent--;
} else {
dn_rt_cache_flush(-1);
}
dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
return 0;
out:
dn_fib_release_info(fi);
return err;
}
static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
struct nlmsghdr *n, struct netlink_skb_parms *req)
{
struct dn_hash *table = (struct dn_hash*)tb->data;
struct dn_fib_node **fp, **del_fp, *f;
int z = r->rtm_dst_len;
struct dn_zone *dz;
dn_fib_key_t key;
int matched;
if (z > 16)
return -EINVAL;
if ((dz = table->dh_zones[z]) == NULL)
return -ESRCH;
dz_key_0(key);
if (attrs[RTA_DST]) {
__le16 dst = nla_get_le16(attrs[RTA_DST]);
if (dst & ~DZ_MASK(dz))
return -EINVAL;
key = dz_key(dst, dz);
}
fp = dn_chain_p(key, dz);
DN_FIB_SCAN(f, fp) {
if (dn_key_eq(f->fn_key, key))
break;
if (dn_key_leq(key, f->fn_key))
return -ESRCH;
}
matched = 0;
del_fp = NULL;
DN_FIB_SCAN_KEY(f, fp, key) {
struct dn_fib_info *fi = DN_FIB_INFO(f);
if (f->fn_state & DN_S_ZOMBIE)
return -ESRCH;
matched++;
if (del_fp == NULL &&
(!r->rtm_type || f->fn_type == r->rtm_type) &&
(r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
(!r->rtm_protocol ||
fi->fib_protocol == r->rtm_protocol) &&
dn_fib_nh_match(r, n, attrs, fi) == 0)
del_fp = fp;
}
if (del_fp) {
f = *del_fp;
dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
if (matched != 1) {
write_lock_bh(&dn_fib_tables_lock);
*del_fp = f->fn_next;
write_unlock_bh(&dn_fib_tables_lock);
if (f->fn_state & DN_S_ACCESSED)
dn_rt_cache_flush(-1);
dn_free_node(f);
dz->dz_nent--;
} else {
f->fn_state |= DN_S_ZOMBIE;
if (f->fn_state & DN_S_ACCESSED) {
f->fn_state &= ~DN_S_ACCESSED;
dn_rt_cache_flush(-1);
}
if (++dn_fib_hash_zombies > 128)
dn_fib_flush();
}
return 0;
}
return -ESRCH;
}
static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
{
int found = 0;
struct dn_fib_node *f;
while((f = *fp) != NULL) {
struct dn_fib_info *fi = DN_FIB_INFO(f);
if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
write_lock_bh(&dn_fib_tables_lock);
*fp = f->fn_next;
write_unlock_bh(&dn_fib_tables_lock);
dn_free_node(f);
found++;
continue;
}
fp = &f->fn_next;
}
return found;
}
static int dn_fib_table_flush(struct dn_fib_table *tb)
{
struct dn_hash *table = (struct dn_hash *)tb->data;
struct dn_zone *dz;
int found = 0;
dn_fib_hash_zombies = 0;
for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
int i;
int tmp = 0;
for(i = dz->dz_divisor-1; i >= 0; i--)
tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
dz->dz_nent -= tmp;
found += tmp;
}
return found;
}
static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowidn *flp, struct dn_fib_res *res)
{
int err;
struct dn_zone *dz;
struct dn_hash *t = (struct dn_hash *)tb->data;
read_lock(&dn_fib_tables_lock);
for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
struct dn_fib_node *f;
dn_fib_key_t k = dz_key(flp->daddr, dz);
for(f = dz_chain(k, dz); f; f = f->fn_next) {
if (!dn_key_eq(k, f->fn_key)) {
if (dn_key_leq(k, f->fn_key))
break;
else
continue;
}
f->fn_state |= DN_S_ACCESSED;
if (f->fn_state&DN_S_ZOMBIE)
continue;
if (f->fn_scope < flp->flowidn_scope)
continue;
err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res);
if (err == 0) {
res->type = f->fn_type;
res->scope = f->fn_scope;
res->prefixlen = dz->dz_order;
goto out;
}
if (err < 0)
goto out;
}
}
err = 1;
out:
read_unlock(&dn_fib_tables_lock);
return err;
}
struct dn_fib_table *dn_fib_get_table(u32 n, int create)
{
struct dn_fib_table *t;
unsigned int h;
if (n < RT_TABLE_MIN)
return NULL;
if (n > RT_TABLE_MAX)
return NULL;
h = n & (DN_FIB_TABLE_HASHSZ - 1);
rcu_read_lock();
hlist_for_each_entry_rcu(t, &dn_fib_table_hash[h], hlist) {
if (t->n == n) {
rcu_read_unlock();
return t;
}
}
rcu_read_unlock();
if (!create)
return NULL;
if (in_interrupt()) {
net_dbg_ratelimited("DECnet: BUG! Attempt to create routing table from interrupt\n");
return NULL;
}
t = kzalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash),
GFP_KERNEL);
if (t == NULL)
return NULL;
t->n = n;
t->insert = dn_fib_table_insert;
t->delete = dn_fib_table_delete;
t->lookup = dn_fib_table_lookup;
t->flush = dn_fib_table_flush;
t->dump = dn_fib_table_dump;
hlist_add_head_rcu(&t->hlist, &dn_fib_table_hash[h]);
return t;
}
struct dn_fib_table *dn_fib_empty_table(void)
{
u32 id;
for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++)
if (dn_fib_get_table(id, 0) == NULL)
return dn_fib_get_table(id, 1);
return NULL;
}
void dn_fib_flush(void)
{
int flushed = 0;
struct dn_fib_table *tb;
unsigned int h;
for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist)
flushed += tb->flush(tb);
}
if (flushed)
dn_rt_cache_flush(-1);
}
void __init dn_fib_table_init(void)
{
dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
sizeof(struct dn_fib_info),
0, SLAB_HWCACHE_ALIGN,
NULL);
}
void __exit dn_fib_table_cleanup(void)
{
struct dn_fib_table *t;
struct hlist_node *next;
unsigned int h;
write_lock(&dn_fib_tables_lock);
for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
hlist_for_each_entry_safe(t, next, &dn_fib_table_hash[h],
hlist) {
hlist_del(&t->hlist);
kfree(t);
}
}
write_unlock(&dn_fib_tables_lock);
}
