diff options
| -rw-r--r-- | net/ipv4/fib_hash.c | 57 |
1 files changed, 38 insertions, 19 deletions
diff --git a/net/ipv4/fib_hash.c b/net/ipv4/fib_hash.c index 10001aa40692..04f05a96b75b 100644 --- a/net/ipv4/fib_hash.c +++ b/net/ipv4/fib_hash.c @@ -57,7 +57,7 @@ struct fib_node { #define EMBEDDED_HASH_SIZE (L1_CACHE_BYTES / sizeof(struct hlist_head)) struct fn_zone { - struct fn_zone *fz_next; /* Next not empty zone */ + struct fn_zone __rcu *fz_next; /* Next not empty zone */ struct hlist_head *fz_hash; /* Hash table pointer */ u32 fz_hashmask; /* (fz_divisor - 1) */ @@ -73,8 +73,8 @@ struct fn_zone { }; struct fn_hash { - struct fn_zone *fn_zones[33]; - struct fn_zone *fn_zone_list; + struct fn_zone *fn_zones[33]; + struct fn_zone __rcu *fn_zone_list; }; static inline u32 fn_hash(__be32 key, struct fn_zone *fz) @@ -219,21 +219,21 @@ fn_new_zone(struct fn_hash *table, int z) fz->fz_mask = inet_make_mask(z); /* Find the first not empty zone with more specific mask */ - for (i=z+1; i<=32; i++) + for (i = z + 1; i <= 32; i++) if (table->fn_zones[i]) break; - write_lock_bh(&fib_hash_lock); - if (i>32) { + if (i > 32) { /* No more specific masks, we are the first. */ - fz->fz_next = table->fn_zone_list; - table->fn_zone_list = fz; + rcu_assign_pointer(fz->fz_next, + rtnl_dereference(table->fn_zone_list)); + rcu_assign_pointer(table->fn_zone_list, fz); } else { - fz->fz_next = table->fn_zones[i]->fz_next; - table->fn_zones[i]->fz_next = fz; + rcu_assign_pointer(fz->fz_next, + rtnl_dereference(table->fn_zones[i]->fz_next)); + rcu_assign_pointer(table->fn_zones[i]->fz_next, fz); } table->fn_zones[z] = fz; fib_hash_genid++; - write_unlock_bh(&fib_hash_lock); return fz; } @@ -245,8 +245,11 @@ int fib_table_lookup(struct fib_table *tb, struct fn_zone *fz; struct fn_hash *t = (struct fn_hash *)tb->tb_data; + rcu_read_lock(); read_lock(&fib_hash_lock); - for (fz = t->fn_zone_list; fz; fz = fz->fz_next) { + for (fz = rcu_dereference(t->fn_zone_list); + fz != NULL; + fz = rcu_dereference(fz->fz_next)) { struct hlist_head *head; struct hlist_node *node; struct fib_node *f; @@ -267,6 +270,7 @@ int fib_table_lookup(struct fib_table *tb, err = 1; out: read_unlock(&fib_hash_lock); + rcu_read_unlock(); return err; } @@ -362,6 +366,7 @@ static struct fib_node *fib_find_node(struct fn_zone *fz, __be32 key) return NULL; } +/* Caller must hold RTNL. */ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) { struct fn_hash *table = (struct fn_hash *) tb->tb_data; @@ -657,13 +662,16 @@ static int fn_flush_list(struct fn_zone *fz, int idx) return found; } +/* caller must hold RTNL. */ int fib_table_flush(struct fib_table *tb) { struct fn_hash *table = (struct fn_hash *) tb->tb_data; struct fn_zone *fz; int found = 0; - for (fz = table->fn_zone_list; fz; fz = fz->fz_next) { + for (fz = rtnl_dereference(table->fn_zone_list); + fz != NULL; + fz = rtnl_dereference(fz->fz_next)) { int i; for (i = fz->fz_divisor - 1; i >= 0; i--) @@ -741,23 +749,29 @@ fn_hash_dump_zone(struct sk_buff *skb, struct netlink_callback *cb, int fib_table_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb) { - int m, s_m; + int m = 0, s_m; struct fn_zone *fz; struct fn_hash *table = (struct fn_hash *)tb->tb_data; s_m = cb->args[2]; + rcu_read_lock(); read_lock(&fib_hash_lock); - for (fz = table->fn_zone_list, m=0; fz; fz = fz->fz_next, m++) { - if (m < s_m) continue; + for (fz = rcu_dereference(table->fn_zone_list); + fz != NULL; + fz = rcu_dereference(fz->fz_next), m++) { + if (m < s_m) + continue; if (fn_hash_dump_zone(skb, cb, tb, fz) < 0) { cb->args[2] = m; read_unlock(&fib_hash_lock); + rcu_read_unlock(); return -1; } memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0])); } read_unlock(&fib_hash_lock); + rcu_read_unlock(); cb->args[2] = m; return skb->len; } @@ -820,8 +834,9 @@ static struct fib_alias *fib_get_first(struct seq_file *seq) iter->genid = fib_hash_genid; iter->valid = 1; - for (iter->zone = table->fn_zone_list; iter->zone; - iter->zone = iter->zone->fz_next) { + for (iter->zone = rcu_dereference(table->fn_zone_list); + iter->zone != NULL; + iter->zone = rcu_dereference(iter->zone->fz_next)) { int maxslot; if (!iter->zone->fz_nent) @@ -906,7 +921,7 @@ static struct fib_alias *fib_get_next(struct seq_file *seq) } } - iter->zone = iter->zone->fz_next; + iter->zone = rcu_dereference(iter->zone->fz_next); if (!iter->zone) goto out; @@ -946,9 +961,11 @@ static struct fib_alias *fib_get_idx(struct seq_file *seq, loff_t pos) static void *fib_seq_start(struct seq_file *seq, loff_t *pos) __acquires(fib_hash_lock) + __acquires(RCU) { void *v = NULL; + rcu_read_lock(); read_lock(&fib_hash_lock); if (fib_get_table(seq_file_net(seq), RT_TABLE_MAIN)) v = *pos ? fib_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; @@ -963,8 +980,10 @@ static void *fib_seq_next(struct seq_file *seq, void *v, loff_t *pos) static void fib_seq_stop(struct seq_file *seq, void *v) __releases(fib_hash_lock) + __releases(RCU) { read_unlock(&fib_hash_lock); + rcu_read_unlock(); } static unsigned fib_flag_trans(int type, __be32 mask, struct fib_info *fi) |