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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/decnet/dn_table.c
Initial import
Diffstat (limited to 'net/decnet/dn_table.c')
-rw-r--r--net/decnet/dn_table.c926
1 files changed, 926 insertions, 0 deletions
diff --git a/net/decnet/dn_table.c b/net/decnet/dn_table.c
new file mode 100644
index 000000000..1540b506e
--- /dev/null
+++ b/net/decnet/dn_table.c
@@ -0,0 +1,926 @@
+/*
+ * 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/tcp.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 */
+ + nla_total_size(TCP_CA_NAME_MAX); /* RTAX_CC_ALGO */
+
+ /* 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);
+ }
+
+ nlmsg_end(skb, nlh);
+ return 0;
+
+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);
+}