summaryrefslogtreecommitdiffstats
path: root/net/ipv4/inet_hashtables.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv4/inet_hashtables.c')
-rw-r--r--net/ipv4/inet_hashtables.c277
1 files changed, 142 insertions, 135 deletions
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 4498190..6a1045d 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -35,7 +35,7 @@ struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
if (tb != NULL) {
- tb->ib_net = hold_net(net);
+ write_pnet(&tb->ib_net, hold_net(net));
tb->port = snum;
tb->fastreuse = 0;
INIT_HLIST_HEAD(&tb->owners);
@@ -51,7 +51,7 @@ void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket
{
if (hlist_empty(&tb->owners)) {
__hlist_del(&tb->node);
- release_net(tb->ib_net);
+ release_net(ib_net(tb));
kmem_cache_free(cachep, tb);
}
}
@@ -110,33 +110,29 @@ void __inet_inherit_port(struct sock *sk, struct sock *child)
EXPORT_SYMBOL_GPL(__inet_inherit_port);
-/*
- * This lock without WQ_FLAG_EXCLUSIVE is good on UP and it can be very bad on SMP.
- * Look, when several writers sleep and reader wakes them up, all but one
- * immediately hit write lock and grab all the cpus. Exclusive sleep solves
- * this, _but_ remember, it adds useless work on UP machines (wake up each
- * exclusive lock release). It should be ifdefed really.
- */
-void inet_listen_wlock(struct inet_hashinfo *hashinfo)
- __acquires(hashinfo->lhash_lock)
+static inline int compute_score(struct sock *sk, struct net *net,
+ const unsigned short hnum, const __be32 daddr,
+ const int dif)
{
- write_lock(&hashinfo->lhash_lock);
-
- if (atomic_read(&hashinfo->lhash_users)) {
- DEFINE_WAIT(wait);
+ int score = -1;
+ struct inet_sock *inet = inet_sk(sk);
- for (;;) {
- prepare_to_wait_exclusive(&hashinfo->lhash_wait,
- &wait, TASK_UNINTERRUPTIBLE);
- if (!atomic_read(&hashinfo->lhash_users))
- break;
- write_unlock_bh(&hashinfo->lhash_lock);
- schedule();
- write_lock_bh(&hashinfo->lhash_lock);
+ if (net_eq(sock_net(sk), net) && inet->num == hnum &&
+ !ipv6_only_sock(sk)) {
+ __be32 rcv_saddr = inet->rcv_saddr;
+ score = sk->sk_family == PF_INET ? 1 : 0;
+ if (rcv_saddr) {
+ if (rcv_saddr != daddr)
+ return -1;
+ score += 2;
+ }
+ if (sk->sk_bound_dev_if) {
+ if (sk->sk_bound_dev_if != dif)
+ return -1;
+ score += 2;
}
-
- finish_wait(&hashinfo->lhash_wait, &wait);
}
+ return score;
}
/*
@@ -145,72 +141,48 @@ void inet_listen_wlock(struct inet_hashinfo *hashinfo)
* remote address for the connection. So always assume those are both
* wildcarded during the search since they can never be otherwise.
*/
-static struct sock *inet_lookup_listener_slow(struct net *net,
- const struct hlist_head *head,
- const __be32 daddr,
- const unsigned short hnum,
- const int dif)
-{
- struct sock *result = NULL, *sk;
- const struct hlist_node *node;
- int hiscore = -1;
-
- sk_for_each(sk, node, head) {
- const struct inet_sock *inet = inet_sk(sk);
-
- if (net_eq(sock_net(sk), net) && inet->num == hnum &&
- !ipv6_only_sock(sk)) {
- const __be32 rcv_saddr = inet->rcv_saddr;
- int score = sk->sk_family == PF_INET ? 1 : 0;
-
- if (rcv_saddr) {
- if (rcv_saddr != daddr)
- continue;
- score += 2;
- }
- if (sk->sk_bound_dev_if) {
- if (sk->sk_bound_dev_if != dif)
- continue;
- score += 2;
- }
- if (score == 5)
- return sk;
- if (score > hiscore) {
- hiscore = score;
- result = sk;
- }
- }
- }
- return result;
-}
-/* Optimize the common listener case. */
+
struct sock *__inet_lookup_listener(struct net *net,
struct inet_hashinfo *hashinfo,
const __be32 daddr, const unsigned short hnum,
const int dif)
{
- struct sock *sk = NULL;
- const struct hlist_head *head;
-
- read_lock(&hashinfo->lhash_lock);
- head = &hashinfo->listening_hash[inet_lhashfn(net, hnum)];
- if (!hlist_empty(head)) {
- const struct inet_sock *inet = inet_sk((sk = __sk_head(head)));
-
- if (inet->num == hnum && !sk->sk_node.next &&
- (!inet->rcv_saddr || inet->rcv_saddr == daddr) &&
- (sk->sk_family == PF_INET || !ipv6_only_sock(sk)) &&
- !sk->sk_bound_dev_if && net_eq(sock_net(sk), net))
- goto sherry_cache;
- sk = inet_lookup_listener_slow(net, head, daddr, hnum, dif);
+ struct sock *sk, *result;
+ struct hlist_nulls_node *node;
+ unsigned int hash = inet_lhashfn(net, hnum);
+ struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
+ int score, hiscore;
+
+ rcu_read_lock();
+begin:
+ result = NULL;
+ hiscore = -1;
+ sk_nulls_for_each_rcu(sk, node, &ilb->head) {
+ score = compute_score(sk, net, hnum, daddr, dif);
+ if (score > hiscore) {
+ result = sk;
+ hiscore = score;
+ }
}
- if (sk) {
-sherry_cache:
- sock_hold(sk);
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (get_nulls_value(node) != hash + LISTENING_NULLS_BASE)
+ goto begin;
+ if (result) {
+ if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
+ result = NULL;
+ else if (unlikely(compute_score(result, net, hnum, daddr,
+ dif) < hiscore)) {
+ sock_put(result);
+ goto begin;
+ }
}
- read_unlock(&hashinfo->lhash_lock);
- return sk;
+ rcu_read_unlock();
+ return result;
}
EXPORT_SYMBOL_GPL(__inet_lookup_listener);
@@ -223,35 +195,65 @@ struct sock * __inet_lookup_established(struct net *net,
INET_ADDR_COOKIE(acookie, saddr, daddr)
const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
struct sock *sk;
- const struct hlist_node *node;
+ const struct hlist_nulls_node *node;
/* Optimize here for direct hit, only listening connections can
* have wildcards anyways.
*/
unsigned int hash = inet_ehashfn(net, daddr, hnum, saddr, sport);
- struct inet_ehash_bucket *head = inet_ehash_bucket(hashinfo, hash);
- rwlock_t *lock = inet_ehash_lockp(hashinfo, hash);
+ unsigned int slot = hash & (hashinfo->ehash_size - 1);
+ struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
- prefetch(head->chain.first);
- read_lock(lock);
- sk_for_each(sk, node, &head->chain) {
+ rcu_read_lock();
+begin:
+ sk_nulls_for_each_rcu(sk, node, &head->chain) {
if (INET_MATCH(sk, net, hash, acookie,
- saddr, daddr, ports, dif))
- goto hit; /* You sunk my battleship! */
+ saddr, daddr, ports, dif)) {
+ if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt)))
+ goto begintw;
+ if (unlikely(!INET_MATCH(sk, net, hash, acookie,
+ saddr, daddr, ports, dif))) {
+ sock_put(sk);
+ goto begin;
+ }
+ goto out;
+ }
}
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (get_nulls_value(node) != slot)
+ goto begin;
+begintw:
/* Must check for a TIME_WAIT'er before going to listener hash. */
- sk_for_each(sk, node, &head->twchain) {
+ sk_nulls_for_each_rcu(sk, node, &head->twchain) {
if (INET_TW_MATCH(sk, net, hash, acookie,
- saddr, daddr, ports, dif))
- goto hit;
+ saddr, daddr, ports, dif)) {
+ if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt))) {
+ sk = NULL;
+ goto out;
+ }
+ if (unlikely(!INET_TW_MATCH(sk, net, hash, acookie,
+ saddr, daddr, ports, dif))) {
+ sock_put(sk);
+ goto begintw;
+ }
+ goto out;
+ }
}
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (get_nulls_value(node) != slot)
+ goto begintw;
sk = NULL;
out:
- read_unlock(lock);
+ rcu_read_unlock();
return sk;
-hit:
- sock_hold(sk);
- goto out;
}
EXPORT_SYMBOL_GPL(__inet_lookup_established);
@@ -270,16 +272,15 @@ static int __inet_check_established(struct inet_timewait_death_row *death_row,
struct net *net = sock_net(sk);
unsigned int hash = inet_ehashfn(net, daddr, lport, saddr, inet->dport);
struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
- rwlock_t *lock = inet_ehash_lockp(hinfo, hash);
+ spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
struct sock *sk2;
- const struct hlist_node *node;
+ const struct hlist_nulls_node *node;
struct inet_timewait_sock *tw;
- prefetch(head->chain.first);
- write_lock(lock);
+ spin_lock(lock);
/* Check TIME-WAIT sockets first. */
- sk_for_each(sk2, node, &head->twchain) {
+ sk_nulls_for_each(sk2, node, &head->twchain) {
tw = inet_twsk(sk2);
if (INET_TW_MATCH(sk2, net, hash, acookie,
@@ -293,7 +294,7 @@ static int __inet_check_established(struct inet_timewait_death_row *death_row,
tw = NULL;
/* And established part... */
- sk_for_each(sk2, node, &head->chain) {
+ sk_nulls_for_each(sk2, node, &head->chain) {
if (INET_MATCH(sk2, net, hash, acookie,
saddr, daddr, ports, dif))
goto not_unique;
@@ -306,9 +307,9 @@ unique:
inet->sport = htons(lport);
sk->sk_hash = hash;
WARN_ON(!sk_unhashed(sk));
- __sk_add_node(sk, &head->chain);
+ __sk_nulls_add_node_rcu(sk, &head->chain);
+ spin_unlock(lock);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
- write_unlock(lock);
if (twp) {
*twp = tw;
@@ -324,7 +325,7 @@ unique:
return 0;
not_unique:
- write_unlock(lock);
+ spin_unlock(lock);
return -EADDRNOTAVAIL;
}
@@ -338,8 +339,8 @@ static inline u32 inet_sk_port_offset(const struct sock *sk)
void __inet_hash_nolisten(struct sock *sk)
{
struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
- struct hlist_head *list;
- rwlock_t *lock;
+ struct hlist_nulls_head *list;
+ spinlock_t *lock;
struct inet_ehash_bucket *head;
WARN_ON(!sk_unhashed(sk));
@@ -349,18 +350,17 @@ void __inet_hash_nolisten(struct sock *sk)
list = &head->chain;
lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
- write_lock(lock);
- __sk_add_node(sk, list);
+ spin_lock(lock);
+ __sk_nulls_add_node_rcu(sk, list);
+ spin_unlock(lock);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
- write_unlock(lock);
}
EXPORT_SYMBOL_GPL(__inet_hash_nolisten);
static void __inet_hash(struct sock *sk)
{
struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
- struct hlist_head *list;
- rwlock_t *lock;
+ struct inet_listen_hashbucket *ilb;
if (sk->sk_state != TCP_LISTEN) {
__inet_hash_nolisten(sk);
@@ -368,14 +368,12 @@ static void __inet_hash(struct sock *sk)
}
WARN_ON(!sk_unhashed(sk));
- list = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
- lock = &hashinfo->lhash_lock;
+ ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
- inet_listen_wlock(hashinfo);
- __sk_add_node(sk, list);
+ spin_lock(&ilb->lock);
+ __sk_nulls_add_node_rcu(sk, &ilb->head);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
- write_unlock(lock);
- wake_up(&hashinfo->lhash_wait);
+ spin_unlock(&ilb->lock);
}
void inet_hash(struct sock *sk)
@@ -390,27 +388,23 @@ EXPORT_SYMBOL_GPL(inet_hash);
void inet_unhash(struct sock *sk)
{
- rwlock_t *lock;
struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
+ spinlock_t *lock;
+ int done;
if (sk_unhashed(sk))
- goto out;
+ return;
- if (sk->sk_state == TCP_LISTEN) {
- local_bh_disable();
- inet_listen_wlock(hashinfo);
- lock = &hashinfo->lhash_lock;
- } else {
+ if (sk->sk_state == TCP_LISTEN)
+ lock = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)].lock;
+ else
lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
- write_lock_bh(lock);
- }
- if (__sk_del_node_init(sk))
+ spin_lock_bh(lock);
+ done =__sk_nulls_del_node_init_rcu(sk);
+ if (done)
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
- write_unlock_bh(lock);
-out:
- if (sk->sk_state == TCP_LISTEN)
- wake_up(&hashinfo->lhash_wait);
+ spin_unlock_bh(lock);
}
EXPORT_SYMBOL_GPL(inet_unhash);
@@ -449,7 +443,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
* unique enough.
*/
inet_bind_bucket_for_each(tb, node, &head->chain) {
- if (tb->ib_net == net && tb->port == port) {
+ if (ib_net(tb) == net && tb->port == port) {
WARN_ON(hlist_empty(&tb->owners));
if (tb->fastreuse >= 0)
goto next_port;
@@ -524,3 +518,16 @@ int inet_hash_connect(struct inet_timewait_death_row *death_row,
}
EXPORT_SYMBOL_GPL(inet_hash_connect);
+
+void inet_hashinfo_init(struct inet_hashinfo *h)
+{
+ int i;
+
+ for (i = 0; i < INET_LHTABLE_SIZE; i++) {
+ spin_lock_init(&h->listening_hash[i].lock);
+ INIT_HLIST_NULLS_HEAD(&h->listening_hash[i].head,
+ i + LISTENING_NULLS_BASE);
+ }
+}
+
+EXPORT_SYMBOL_GPL(inet_hashinfo_init);
OpenPOWER on IntegriCloud