diff options
Diffstat (limited to 'net/ipv4/fib_semantics.c')
| -rw-r--r-- | net/ipv4/fib_semantics.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 1bf6fb906cfc..b15857d2b77e 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -1136,6 +1136,62 @@ int fib_sync_down_dev(struct net_device *dev, int force) return ret; } +/* Must be invoked inside of an RCU protected region. */ +void fib_select_default(struct fib_result *res) +{ + struct fib_info *fi = NULL, *last_resort = NULL; + struct list_head *fa_head = res->fa_head; + struct fib_table *tb = res->table; + int order = -1, last_idx = -1; + struct fib_alias *fa; + + list_for_each_entry_rcu(fa, fa_head, fa_list) { + struct fib_info *next_fi = fa->fa_info; + + if (fa->fa_scope != res->scope || + fa->fa_type != RTN_UNICAST) + continue; + + if (next_fi->fib_priority > res->fi->fib_priority) + break; + if (!next_fi->fib_nh[0].nh_gw || + next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK) + continue; + + fib_alias_accessed(fa); + + if (fi == NULL) { + if (next_fi != res->fi) + break; + } else if (!fib_detect_death(fi, order, &last_resort, + &last_idx, tb->tb_default)) { + fib_result_assign(res, fi); + tb->tb_default = order; + goto out; + } + fi = next_fi; + order++; + } + + if (order <= 0 || fi == NULL) { + tb->tb_default = -1; + goto out; + } + + if (!fib_detect_death(fi, order, &last_resort, &last_idx, + tb->tb_default)) { + fib_result_assign(res, fi); + tb->tb_default = order; + goto out; + } + + if (last_idx >= 0) + fib_result_assign(res, last_resort); + tb->tb_default = last_idx; +out: + rcu_read_unlock(); +} + #ifdef CONFIG_IP_ROUTE_MULTIPATH /* |