diff options
Diffstat (limited to 'net/ipv4/fib_trie.c')
| -rw-r--r-- | net/ipv4/fib_trie.c | 351 |
1 files changed, 260 insertions, 91 deletions
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index e2ffc2a5c7db..2919d1a10cfd 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -50,7 +50,7 @@ #define VERSION "0.409" -#include <asm/uaccess.h> +#include <linux/uaccess.h> #include <linux/bitops.h> #include <linux/types.h> #include <linux/kernel.h> @@ -73,6 +73,7 @@ #include <linux/slab.h> #include <linux/export.h> #include <linux/vmalloc.h> +#include <linux/notifier.h> #include <net/net_namespace.h> #include <net/ip.h> #include <net/protocol.h> @@ -80,10 +81,136 @@ #include <net/tcp.h> #include <net/sock.h> #include <net/ip_fib.h> -#include <net/switchdev.h> #include <trace/events/fib.h> #include "fib_lookup.h" +static unsigned int fib_seq_sum(void) +{ + unsigned int fib_seq = 0; + struct net *net; + + rtnl_lock(); + for_each_net(net) + fib_seq += net->ipv4.fib_seq; + rtnl_unlock(); + + return fib_seq; +} + +static ATOMIC_NOTIFIER_HEAD(fib_chain); + +static int call_fib_notifier(struct notifier_block *nb, struct net *net, + enum fib_event_type event_type, + struct fib_notifier_info *info) +{ + info->net = net; + return nb->notifier_call(nb, event_type, info); +} + +static void fib_rules_notify(struct net *net, struct notifier_block *nb, + enum fib_event_type event_type) +{ +#ifdef CONFIG_IP_MULTIPLE_TABLES + struct fib_notifier_info info; + + if (net->ipv4.fib_has_custom_rules) + call_fib_notifier(nb, net, event_type, &info); +#endif +} + +static void fib_notify(struct net *net, struct notifier_block *nb, + enum fib_event_type event_type); + +static int call_fib_entry_notifier(struct notifier_block *nb, struct net *net, + enum fib_event_type event_type, u32 dst, + int dst_len, struct fib_info *fi, + u8 tos, u8 type, u32 tb_id, u32 nlflags) +{ + struct fib_entry_notifier_info info = { + .dst = dst, + .dst_len = dst_len, + .fi = fi, + .tos = tos, + .type = type, + .tb_id = tb_id, + .nlflags = nlflags, + }; + return call_fib_notifier(nb, net, event_type, &info.info); +} + +static bool fib_dump_is_consistent(struct notifier_block *nb, + void (*cb)(struct notifier_block *nb), + unsigned int fib_seq) +{ + atomic_notifier_chain_register(&fib_chain, nb); + if (fib_seq == fib_seq_sum()) + return true; + atomic_notifier_chain_unregister(&fib_chain, nb); + if (cb) + cb(nb); + return false; +} + +#define FIB_DUMP_MAX_RETRIES 5 +int register_fib_notifier(struct notifier_block *nb, + void (*cb)(struct notifier_block *nb)) +{ + int retries = 0; + + do { + unsigned int fib_seq = fib_seq_sum(); + struct net *net; + + /* Mutex semantics guarantee that every change done to + * FIB tries before we read the change sequence counter + * is now visible to us. + */ + rcu_read_lock(); + for_each_net_rcu(net) { + fib_rules_notify(net, nb, FIB_EVENT_RULE_ADD); + fib_notify(net, nb, FIB_EVENT_ENTRY_ADD); + } + rcu_read_unlock(); + + if (fib_dump_is_consistent(nb, cb, fib_seq)) + return 0; + } while (++retries < FIB_DUMP_MAX_RETRIES); + + return -EBUSY; +} +EXPORT_SYMBOL(register_fib_notifier); + +int unregister_fib_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_unregister(&fib_chain, nb); +} +EXPORT_SYMBOL(unregister_fib_notifier); + +int call_fib_notifiers(struct net *net, enum fib_event_type event_type, + struct fib_notifier_info *info) +{ + net->ipv4.fib_seq++; + info->net = net; + return atomic_notifier_call_chain(&fib_chain, event_type, info); +} + +static int call_fib_entry_notifiers(struct net *net, + enum fib_event_type event_type, u32 dst, + int dst_len, struct fib_info *fi, + u8 tos, u8 type, u32 tb_id, u32 nlflags) +{ + struct fib_entry_notifier_info info = { + .dst = dst, + .dst_len = dst_len, + .fi = fi, + .tos = tos, + .type = type, + .tb_id = tb_id, + .nlflags = nlflags, + }; + return call_fib_notifiers(net, event_type, &info.info); +} + #define MAX_STAT_DEPTH 32 #define KEYLENGTH (8*sizeof(t_key)) @@ -681,6 +808,13 @@ static unsigned char update_suffix(struct key_vector *tn) { unsigned char slen = tn->pos; unsigned long stride, i; + unsigned char slen_max; + + /* only vector 0 can have a suffix length greater than or equal to + * tn->pos + tn->bits, the second highest node will have a suffix + * length at most of tn->pos + tn->bits - 1 + */ + slen_max = min_t(unsigned char, tn->pos + tn->bits - 1, tn->slen); /* search though the list of children looking for nodes that might * have a suffix greater than the one we currently have. This is @@ -698,12 +832,8 @@ static unsigned char update_suffix(struct key_vector *tn) slen = n->slen; i &= ~(stride - 1); - /* if slen covers all but the last bit we can stop here - * there will be nothing longer than that since only node - * 0 and 1 << (bits - 1) could have that as their suffix - * length. - */ - if ((slen + 1) >= (tn->pos + tn->bits)) + /* stop searching if we have hit the maximum possible value */ + if (slen >= slen_max) break; } @@ -875,39 +1005,27 @@ static struct key_vector *resize(struct trie *t, struct key_vector *tn) return collapse(t, tn); /* update parent in case halve failed */ - tp = node_parent(tn); - - /* Return if at least one deflate was run */ - if (max_work != MAX_WORK) - return tp; - - /* push the suffix length to the parent node */ - if (tn->slen > tn->pos) { - unsigned char slen = update_suffix(tn); - - if (slen > tp->slen) - tp->slen = slen; - } - - return tp; + return node_parent(tn); } -static void leaf_pull_suffix(struct key_vector *tp, struct key_vector *l) +static void node_pull_suffix(struct key_vector *tn, unsigned char slen) { - while ((tp->slen > tp->pos) && (tp->slen > l->slen)) { - if (update_suffix(tp) > l->slen) + unsigned char node_slen = tn->slen; + + while ((node_slen > tn->pos) && (node_slen > slen)) { + slen = update_suffix(tn); + if (node_slen == slen) break; - tp = node_parent(tp); + + tn = node_parent(tn); + node_slen = tn->slen; } } -static void leaf_push_suffix(struct key_vector *tn, struct key_vector *l) +static void node_push_suffix(struct key_vector *tn, unsigned char slen) { - /* if this is a new leaf then tn will be NULL and we can sort - * out parent suffix lengths as a part of trie_rebalance - */ - while (tn->slen < l->slen) { - tn->slen = l->slen; + while (tn->slen < slen) { + tn->slen = slen; tn = node_parent(tn); } } @@ -1028,6 +1146,7 @@ static int fib_insert_node(struct trie *t, struct key_vector *tp, } /* Case 3: n is NULL, and will just insert a new leaf */ + node_push_suffix(tp, new->fa_slen); NODE_INIT_PARENT(l, tp); put_child_root(tp, key, l); trie_rebalance(t, tp); @@ -1069,19 +1188,20 @@ static int fib_insert_alias(struct trie *t, struct key_vector *tp, /* if we added to the tail node then we need to update slen */ if (l->slen < new->fa_slen) { l->slen = new->fa_slen; - leaf_push_suffix(tp, l); + node_push_suffix(tp, new->fa_slen); } return 0; } /* Caller must hold RTNL. */ -int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) +int fib_table_insert(struct net *net, struct fib_table *tb, + struct fib_config *cfg) { struct trie *t = (struct trie *)tb->tb_data; struct fib_alias *fa, *new_fa; struct key_vector *l, *tp; - unsigned int nlflags = 0; + u16 nlflags = NLM_F_EXCL; struct fib_info *fi; u8 plen = cfg->fc_dst_len; u8 slen = KEYLENGTH - plen; @@ -1126,6 +1246,8 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) if (cfg->fc_nlflags & NLM_F_EXCL) goto out; + nlflags &= ~NLM_F_EXCL; + /* We have 2 goals: * 1. Find exact match for type, scope, fib_info to avoid * duplicate routes @@ -1151,6 +1273,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) struct fib_info *fi_drop; u8 state; + nlflags |= NLM_F_REPLACE; fa = fa_first; if (fa_match) { if (fa == fa_match) @@ -1172,17 +1295,6 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) new_fa->tb_id = tb->tb_id; new_fa->fa_default = -1; - err = switchdev_fib_ipv4_add(key, plen, fi, - new_fa->fa_tos, - cfg->fc_type, - cfg->fc_nlflags, - tb->tb_id); - if (err) { - switchdev_fib_ipv4_abort(fi); - kmem_cache_free(fn_alias_kmem, new_fa); - goto out; - } - hlist_replace_rcu(&fa->fa_list, &new_fa->fa_list); alias_free_mem_rcu(fa); @@ -1190,8 +1302,13 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) fib_release_info(fi_drop); if (state & FA_S_ACCESSED) rt_cache_flush(cfg->fc_nlinfo.nl_net); + + call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, + key, plen, fi, + new_fa->fa_tos, cfg->fc_type, + tb->tb_id, cfg->fc_nlflags); rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, - tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE); + tb->tb_id, &cfg->fc_nlinfo, nlflags); goto succeeded; } @@ -1203,7 +1320,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) goto out; if (cfg->fc_nlflags & NLM_F_APPEND) - nlflags = NLM_F_APPEND; + nlflags |= NLM_F_APPEND; else fa = fa_first; } @@ -1211,6 +1328,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) if (!(cfg->fc_nlflags & NLM_F_CREATE)) goto out; + nlflags |= NLM_F_CREATE; err = -ENOBUFS; new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL); if (!new_fa) @@ -1224,30 +1342,22 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) new_fa->tb_id = tb->tb_id; new_fa->fa_default = -1; - /* (Optionally) offload fib entry to switch hardware. */ - err = switchdev_fib_ipv4_add(key, plen, fi, tos, cfg->fc_type, - cfg->fc_nlflags, tb->tb_id); - if (err) { - switchdev_fib_ipv4_abort(fi); - goto out_free_new_fa; - } - /* Insert new entry to the list. */ err = fib_insert_alias(t, tp, l, new_fa, fa, key); if (err) - goto out_sw_fib_del; + goto out_free_new_fa; if (!plen) tb->tb_num_default++; rt_cache_flush(cfg->fc_nlinfo.nl_net); + call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, key, plen, fi, tos, + cfg->fc_type, tb->tb_id, cfg->fc_nlflags); rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, new_fa->tb_id, &cfg->fc_nlinfo, nlflags); succeeded: return 0; -out_sw_fib_del: - switchdev_fib_ipv4_del(key, plen, fi, tos, cfg->fc_type, tb->tb_id); out_free_new_fa: kmem_cache_free(fn_alias_kmem, new_fa); out: @@ -1470,6 +1580,8 @@ static void fib_remove_alias(struct trie *t, struct key_vector *tp, * out parent suffix lengths as a part of trie_rebalance */ if (hlist_empty(&l->leaf)) { + if (tp->slen == l->slen) + node_pull_suffix(tp, tp->pos); put_child_root(tp, l->key, NULL); node_free(l); trie_rebalance(t, tp); @@ -1482,11 +1594,12 @@ static void fib_remove_alias(struct trie *t, struct key_vector *tp, /* update the trie with the latest suffix length */ l->slen = fa->fa_slen; - leaf_pull_suffix(tp, l); + node_pull_suffix(tp, fa->fa_slen); } /* Caller must hold RTNL. */ -int fib_table_delete(struct fib_table *tb, struct fib_config *cfg) +int fib_table_delete(struct net *net, struct fib_table *tb, + struct fib_config *cfg) { struct trie *t = (struct trie *) tb->tb_data; struct fib_alias *fa, *fa_to_delete; @@ -1539,9 +1652,9 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg) if (!fa_to_delete) return -ESRCH; - switchdev_fib_ipv4_del(key, plen, fa_to_delete->fa_info, tos, - cfg->fc_type, tb->tb_id); - + call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, key, plen, + fa_to_delete->fa_info, tos, cfg->fc_type, + tb->tb_id, 0); rtmsg_fib(RTM_DELROUTE, htonl(key), fa_to_delete, plen, tb->tb_id, &cfg->fc_nlinfo, 0); @@ -1713,8 +1826,10 @@ struct fib_table *fib_trie_unmerge(struct fib_table *oldtb) local_l = fib_find_node(lt, &local_tp, l->key); if (fib_insert_alias(lt, local_tp, local_l, new_fa, - NULL, l->key)) + NULL, l->key)) { + kmem_cache_free(fn_alias_kmem, new_fa); goto out; + } } /* stop loop if key wrapped back to 0 */ @@ -1751,6 +1866,10 @@ void fib_table_flush_external(struct fib_table *tb) if (IS_TRIE(pn)) break; + /* update the suffix to address pulled leaves */ + if (pn->slen > pn->pos) + update_suffix(pn); + /* resize completed node */ pn = resize(t, pn); cindex = get_index(pkey, pn); @@ -1772,8 +1891,6 @@ void fib_table_flush_external(struct fib_table *tb) } hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) { - struct fib_info *fi = fa->fa_info; - /* if alias was cloned to local then we just * need to remove the local copy from main */ @@ -1785,13 +1902,6 @@ void fib_table_flush_external(struct fib_table *tb) /* record local slen */ slen = fa->fa_slen; - - if (!fi || !(fi->fib_flags & RTNH_F_OFFLOAD)) - continue; - - switchdev_fib_ipv4_del(n->key, KEYLENGTH - fa->fa_slen, - fi, fa->fa_tos, fa->fa_type, - tb->tb_id); } /* update leaf slen */ @@ -1805,7 +1915,7 @@ void fib_table_flush_external(struct fib_table *tb) } /* Caller must hold RTNL. */ -int fib_table_flush(struct fib_table *tb) +int fib_table_flush(struct net *net, struct fib_table *tb) { struct trie *t = (struct trie *)tb->tb_data; struct key_vector *pn = t->kv; @@ -1826,6 +1936,10 @@ int fib_table_flush(struct fib_table *tb) if (IS_TRIE(pn)) break; + /* update the suffix to address pulled leaves */ + if (pn->slen > pn->pos) + update_suffix(pn); + /* resize completed node */ pn = resize(t, pn); cindex = get_index(pkey, pn); @@ -1854,9 +1968,11 @@ int fib_table_flush(struct fib_table *tb) continue; } - switchdev_fib_ipv4_del(n->key, KEYLENGTH - fa->fa_slen, - fi, fa->fa_tos, fa->fa_type, - tb->tb_id); + call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, + n->key, + KEYLENGTH - fa->fa_slen, + fi, fa->fa_tos, fa->fa_type, + tb->tb_id, 0); hlist_del_rcu(&fa->fa_list); fib_release_info(fa->fa_info); alias_free_mem_rcu(fa); @@ -1876,6 +1992,62 @@ int fib_table_flush(struct fib_table *tb) return found; } +static void fib_leaf_notify(struct net *net, struct key_vector *l, + struct fib_table *tb, struct notifier_block *nb, + enum fib_event_type event_type) +{ + struct fib_alias *fa; + + hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) { + struct fib_info *fi = fa->fa_info; + + if (!fi) + continue; + + /* local and main table can share the same trie, + * so don't notify twice for the same entry. + */ + if (tb->tb_id != fa->tb_id) + continue; + + call_fib_entry_notifier(nb, net, event_type, l->key, + KEYLENGTH - fa->fa_slen, fi, fa->fa_tos, + fa->fa_type, fa->tb_id, 0); + } +} + +static void fib_table_notify(struct net *net, struct fib_table *tb, + struct notifier_block *nb, + enum fib_event_type event_type) +{ + struct trie *t = (struct trie *)tb->tb_data; + struct key_vector *l, *tp = t->kv; + t_key key = 0; + + while ((l = leaf_walk_rcu(&tp, key)) != NULL) { + fib_leaf_notify(net, l, tb, nb, event_type); + + key = l->key + 1; + /* stop in case of wrap around */ + if (key < l->key) + break; + } +} + +static void fib_notify(struct net *net, struct notifier_block *nb, + enum fib_event_type event_type) +{ + unsigned int h; + + for (h = 0; h < FIB_TABLE_HASHSZ; h++) { + struct hlist_head *head = &net->ipv4.fib_table_hash[h]; + struct fib_table *tb; + + hlist_for_each_entry_rcu(tb, head, tb_hlist) + fib_table_notify(net, tb, nb, event_type); + } +} + static void __trie_free_rcu(struct rcu_head *head) { struct fib_table *tb = container_of(head, struct fib_table, rcu); @@ -2455,22 +2627,19 @@ static struct key_vector *fib_route_get_idx(struct fib_route_iter *iter, struct key_vector *l, **tp = &iter->tnode; t_key key; - /* use cache location of next-to-find key */ + /* use cached location of previously found key */ if (iter->pos > 0 && pos >= iter->pos) { - pos -= iter->pos; key = iter->key; } else { - iter->pos = 0; + iter->pos = 1; key = 0; } - while ((l = leaf_walk_rcu(tp, key)) != NULL) { + pos -= iter->pos; + + while ((l = leaf_walk_rcu(tp, key)) && (pos-- > 0)) { key = l->key + 1; iter->pos++; - - if (--pos <= 0) - break; - l = NULL; /* handle unlikely case of a key wrap */ @@ -2479,7 +2648,7 @@ static struct key_vector *fib_route_get_idx(struct fib_route_iter *iter, } if (l) - iter->key = key; /* remember it */ + iter->key = l->key; /* remember it */ else iter->pos = 0; /* forget it */ @@ -2507,7 +2676,7 @@ static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos) return fib_route_get_idx(iter, *pos); iter->pos = 0; - iter->key = 0; + iter->key = KEY_MAX; return SEQ_START_TOKEN; } @@ -2516,7 +2685,7 @@ static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct fib_route_iter *iter = seq->private; struct key_vector *l = NULL; - t_key key = iter->key; + t_key key = iter->key + 1; ++*pos; @@ -2525,7 +2694,7 @@ static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos) l = leaf_walk_rcu(&iter->tnode, key); if (l) { - iter->key = l->key + 1; + iter->key = l->key; iter->pos++; } else { iter->pos = 0; |