kernel-ark/net/decnet/dn_table.c
Pablo Neira Ayuso 1ce85fe402 netlink: change nlmsg_notify() return value logic
This patch changes the return value of nlmsg_notify() as follows:

If NETLINK_BROADCAST_ERROR is set by any of the listeners and
an error in the delivery happened, return the broadcast error;
else if there are no listeners apart from the socket that
requested a change with the echo flag, return the result of the
unicast notification. Thus, with this patch, the unicast
notification is handled in the same way of a broadcast listener
that has set the NETLINK_BROADCAST_ERROR socket flag.

This patch is useful in case that the caller of nlmsg_notify()
wants to know the result of the delivery of a netlink notification
(including the broadcast delivery) and take any action in case
that the delivery failed. For example, ctnetlink can drop packets
if the event delivery failed to provide reliable logging and
state-synchronization at the cost of dropping packets.

This patch also modifies the rtnetlink code to ignore the return
value of rtnl_notify() in all callers. The function rtnl_notify()
(before this patch) returned the error of the unicast notification
which makes rtnl_set_sk_err() reports errors to all listeners. This
is not of any help since the origin of the change (the socket that
requested the echoing) notices the ENOBUFS error if the notification
fails and should resync itself.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-24 23:18:28 -08:00

908 lines
20 KiB
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/sockios.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <asm/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 dz_prefix(key,dz) ((key).datum)
#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)
{
int i;
struct dn_fib_node *f, **fp, *next;
for(i = 0; i < old_divisor; i++) {
for(f = old_ht[i]; f; f = f->fn_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 dn_kern_rta *rta, struct dn_fib_info *fi)
{
struct rtnexthop *nhp;
int nhlen;
if (rta->rta_priority && *rta->rta_priority != fi->fib_priority)
return 1;
if (rta->rta_oif || rta->rta_gw) {
if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
(!rta->rta_gw || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 2) == 0))
return 0;
return 1;
}
if (rta->rta_mp == NULL)
return 0;
nhp = RTA_DATA(rta->rta_mp);
nhlen = RTA_PAYLOAD(rta->rta_mp);
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) {
gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
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 pid, 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;
unsigned char *b = skb_tail_pointer(skb);
nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*rtm), flags);
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;
RTA_PUT_U32(skb, RTA_TABLE, tb_id);
rtm->rtm_flags = fi->fib_flags;
rtm->rtm_scope = scope;
rtm->rtm_type = type;
if (rtm->rtm_dst_len)
RTA_PUT(skb, RTA_DST, 2, dst);
rtm->rtm_protocol = fi->fib_protocol;
if (fi->fib_priority)
RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
goto rtattr_failure;
if (fi->fib_nhs == 1) {
if (fi->fib_nh->nh_gw)
RTA_PUT(skb, RTA_GATEWAY, 2, &fi->fib_nh->nh_gw);
if (fi->fib_nh->nh_oif)
RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
}
if (fi->fib_nhs > 1) {
struct rtnexthop *nhp;
struct rtattr *mp_head;
if (skb_tailroom(skb) <= RTA_SPACE(0))
goto rtattr_failure;
mp_head = (struct rtattr *)skb_put(skb, RTA_SPACE(0));
for_nexthops(fi) {
if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
goto rtattr_failure;
nhp = (struct rtnexthop *)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
nhp->rtnh_flags = nh->nh_flags & 0xFF;
nhp->rtnh_hops = nh->nh_weight - 1;
nhp->rtnh_ifindex = nh->nh_oif;
if (nh->nh_gw)
RTA_PUT(skb, RTA_GATEWAY, 2, &nh->nh_gw);
nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
} endfor_nexthops(fi);
mp_head->rta_type = RTA_MULTIPATH;
mp_head->rta_len = skb_tail_pointer(skb) - (u8 *)mp_head;
}
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
return skb->len;
nlmsg_failure:
rtattr_failure:
nlmsg_trim(skb, b);
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 pid = req ? req->pid : 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, pid, 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, pid, 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).pid,
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;
struct hlist_node *node;
int dumped = 0;
if (net != &init_net)
return 0;
if (NLMSG_PAYLOAD(cb->nlh, 0) >= 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, node, &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 dn_kern_rta *rta, 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 (rta->rta_dst) {
__le16 dst;
memcpy(&dst, rta->rta_dst, 2);
if (dst & ~DZ_MASK(dz))
return -EINVAL;
key = dz_key(dst, dz);
}
if ((fi = dn_fib_create_info(r, rta, 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 dn_kern_rta *rta, 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 (rta->rta_dst) {
__le16 dst;
memcpy(&dst, rta->rta_dst, 2);
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, rta, 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 flowi *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->fld_dst, 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->fld_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;
struct hlist_node *node;
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, node, &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_ratelimit()) {
printk(KERN_DEBUG "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;
struct hlist_node *node;
unsigned int h;
for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
hlist_for_each_entry(tb, node, &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 *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, node, next, &dn_fib_table_hash[h],
hlist) {
hlist_del(&t->hlist);
kfree(t);
}
}
write_unlock(&dn_fib_tables_lock);
}