#define NF_CONNTRACK_VERSION "0.5.0"
-DEFINE_RWLOCK(nf_conntrack_lock);
+DEFINE_SPINLOCK(nf_conntrack_lock);
EXPORT_SYMBOL_GPL(nf_conntrack_lock);
/* nf_conntrack_standalone needs this */
static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,
unsigned int size, unsigned int rnd)
{
- unsigned int a, b;
-
- a = jhash2(tuple->src.u3.all, ARRAY_SIZE(tuple->src.u3.all),
- (tuple->src.l3num << 16) | tuple->dst.protonum);
- b = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all),
- ((__force __u16)tuple->src.u.all << 16) |
- (__force __u16)tuple->dst.u.all);
-
- return ((u64)jhash_2words(a, b, rnd) * size) >> 32;
+ unsigned int n;
+ u_int32_t h;
+
+ /* The direction must be ignored, so we hash everything up to the
+ * destination ports (which is a multiple of 4) and treat the last
+ * three bytes manually.
+ */
+ n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32);
+ h = jhash2((u32 *)tuple, n,
+ rnd ^ (((__force __u16)tuple->dst.u.all << 16) |
+ tuple->dst.protonum));
+
+ return ((u64)h * size) >> 32;
}
static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
clean_from_lists(struct nf_conn *ct)
{
pr_debug("clean_from_lists(%p)\n", ct);
- hlist_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode);
- hlist_del(&ct->tuplehash[IP_CT_DIR_REPLY].hnode);
+ hlist_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode);
+ hlist_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnode);
/* Destroy all pending expectations */
nf_ct_remove_expectations(ct);
rcu_read_unlock();
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
/* Expectations will have been removed in clean_from_lists,
* except TFTP can create an expectation on the first packet,
* before connection is in the list, so we need to clean here,
}
NF_CT_STAT_INC(delete);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
if (ct->master)
nf_ct_put(ct->master);
rcu_read_unlock();
}
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
/* Inside lock so preempt is disabled on module removal path.
* Otherwise we can get spurious warnings. */
NF_CT_STAT_INC(delete_list);
clean_from_lists(ct);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
nf_ct_put(ct);
}
struct nf_conntrack_tuple_hash *
-__nf_conntrack_find(const struct nf_conntrack_tuple *tuple,
- const struct nf_conn *ignored_conntrack)
+__nf_conntrack_find(const struct nf_conntrack_tuple *tuple)
{
struct nf_conntrack_tuple_hash *h;
struct hlist_node *n;
unsigned int hash = hash_conntrack(tuple);
- hlist_for_each_entry(h, n, &nf_conntrack_hash[hash], hnode) {
- if (nf_ct_tuplehash_to_ctrack(h) != ignored_conntrack &&
- nf_ct_tuple_equal(tuple, &h->tuple)) {
+ /* Disable BHs the entire time since we normally need to disable them
+ * at least once for the stats anyway.
+ */
+ local_bh_disable();
+ hlist_for_each_entry_rcu(h, n, &nf_conntrack_hash[hash], hnode) {
+ if (nf_ct_tuple_equal(tuple, &h->tuple)) {
NF_CT_STAT_INC(found);
+ local_bh_enable();
return h;
}
NF_CT_STAT_INC(searched);
}
+ local_bh_enable();
return NULL;
}
nf_conntrack_find_get(const struct nf_conntrack_tuple *tuple)
{
struct nf_conntrack_tuple_hash *h;
+ struct nf_conn *ct;
- read_lock_bh(&nf_conntrack_lock);
- h = __nf_conntrack_find(tuple, NULL);
- if (h)
- atomic_inc(&nf_ct_tuplehash_to_ctrack(h)->ct_general.use);
- read_unlock_bh(&nf_conntrack_lock);
+ rcu_read_lock();
+ h = __nf_conntrack_find(tuple);
+ if (h) {
+ ct = nf_ct_tuplehash_to_ctrack(h);
+ if (unlikely(!atomic_inc_not_zero(&ct->ct_general.use)))
+ h = NULL;
+ }
+ rcu_read_unlock();
return h;
}
unsigned int hash,
unsigned int repl_hash)
{
- hlist_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode,
- &nf_conntrack_hash[hash]);
- hlist_add_head(&ct->tuplehash[IP_CT_DIR_REPLY].hnode,
- &nf_conntrack_hash[repl_hash]);
+ hlist_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode,
+ &nf_conntrack_hash[hash]);
+ hlist_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnode,
+ &nf_conntrack_hash[repl_hash]);
}
void nf_conntrack_hash_insert(struct nf_conn *ct)
hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
__nf_conntrack_hash_insert(ct, hash, repl_hash);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
}
EXPORT_SYMBOL_GPL(nf_conntrack_hash_insert);
NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
pr_debug("Confirming conntrack %p\n", ct);
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
/* See if there's one in the list already, including reverse:
NAT could have grabbed it without realizing, since we're
atomic_inc(&ct->ct_general.use);
set_bit(IPS_CONFIRMED_BIT, &ct->status);
NF_CT_STAT_INC(insert);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
help = nfct_help(ct);
if (help && help->helper)
nf_conntrack_event_cache(IPCT_HELPER, skb);
out:
NF_CT_STAT_INC(insert_failed);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
return NF_DROP;
}
EXPORT_SYMBOL_GPL(__nf_conntrack_confirm);
const struct nf_conn *ignored_conntrack)
{
struct nf_conntrack_tuple_hash *h;
+ struct hlist_node *n;
+ unsigned int hash = hash_conntrack(tuple);
- read_lock_bh(&nf_conntrack_lock);
- h = __nf_conntrack_find(tuple, ignored_conntrack);
- read_unlock_bh(&nf_conntrack_lock);
+ /* Disable BHs the entire time since we need to disable them at
+ * least once for the stats anyway.
+ */
+ rcu_read_lock_bh();
+ hlist_for_each_entry_rcu(h, n, &nf_conntrack_hash[hash], hnode) {
+ if (nf_ct_tuplehash_to_ctrack(h) != ignored_conntrack &&
+ nf_ct_tuple_equal(tuple, &h->tuple)) {
+ NF_CT_STAT_INC(found);
+ rcu_read_unlock_bh();
+ return 1;
+ }
+ NF_CT_STAT_INC(searched);
+ }
+ rcu_read_unlock_bh();
- return h != NULL;
+ return 0;
}
EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken);
/* There's a small race here where we may free a just-assured
connection. Too bad: we're in trouble anyway. */
-static int early_drop(unsigned int hash)
+static noinline int early_drop(unsigned int hash)
{
/* Use oldest entry, which is roughly LRU */
struct nf_conntrack_tuple_hash *h;
unsigned int i, cnt = 0;
int dropped = 0;
- read_lock_bh(&nf_conntrack_lock);
+ rcu_read_lock();
for (i = 0; i < nf_conntrack_htable_size; i++) {
- hlist_for_each_entry(h, n, &nf_conntrack_hash[hash], hnode) {
+ hlist_for_each_entry_rcu(h, n, &nf_conntrack_hash[hash],
+ hnode) {
tmp = nf_ct_tuplehash_to_ctrack(h);
if (!test_bit(IPS_ASSURED_BIT, &tmp->status))
ct = tmp;
cnt++;
}
+
+ if (ct && unlikely(!atomic_inc_not_zero(&ct->ct_general.use)))
+ ct = NULL;
if (ct || cnt >= NF_CT_EVICTION_RANGE)
break;
hash = (hash + 1) % nf_conntrack_htable_size;
}
- if (ct)
- atomic_inc(&ct->ct_general.use);
- read_unlock_bh(&nf_conntrack_lock);
+ rcu_read_unlock();
if (!ct)
return dropped;
struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
const struct nf_conntrack_tuple *repl)
{
- struct nf_conn *conntrack = NULL;
+ struct nf_conn *ct = NULL;
if (unlikely(!nf_conntrack_hash_rnd_initted)) {
get_random_bytes(&nf_conntrack_hash_rnd, 4);
/* We don't want any race condition at early drop stage */
atomic_inc(&nf_conntrack_count);
- if (nf_conntrack_max
- && atomic_read(&nf_conntrack_count) > nf_conntrack_max) {
+ if (nf_conntrack_max &&
+ unlikely(atomic_read(&nf_conntrack_count) > nf_conntrack_max)) {
unsigned int hash = hash_conntrack(orig);
if (!early_drop(hash)) {
atomic_dec(&nf_conntrack_count);
}
}
- conntrack = kmem_cache_zalloc(nf_conntrack_cachep, GFP_ATOMIC);
- if (conntrack == NULL) {
+ ct = kmem_cache_zalloc(nf_conntrack_cachep, GFP_ATOMIC);
+ if (ct == NULL) {
pr_debug("nf_conntrack_alloc: Can't alloc conntrack.\n");
atomic_dec(&nf_conntrack_count);
return ERR_PTR(-ENOMEM);
}
- atomic_set(&conntrack->ct_general.use, 1);
- conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
- conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
+ atomic_set(&ct->ct_general.use, 1);
+ ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
+ ct->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
/* Don't set timer yet: wait for confirmation */
- setup_timer(&conntrack->timeout, death_by_timeout,
- (unsigned long)conntrack);
+ setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct);
+ INIT_RCU_HEAD(&ct->rcu);
- return conntrack;
+ return ct;
}
EXPORT_SYMBOL_GPL(nf_conntrack_alloc);
-void nf_conntrack_free(struct nf_conn *conntrack)
+static void nf_conntrack_free_rcu(struct rcu_head *head)
{
- nf_ct_ext_free(conntrack);
- kmem_cache_free(nf_conntrack_cachep, conntrack);
+ struct nf_conn *ct = container_of(head, struct nf_conn, rcu);
+
+ nf_ct_ext_free(ct);
+ kmem_cache_free(nf_conntrack_cachep, ct);
atomic_dec(&nf_conntrack_count);
}
+
+void nf_conntrack_free(struct nf_conn *ct)
+{
+ call_rcu(&ct->rcu, nf_conntrack_free_rcu);
+}
EXPORT_SYMBOL_GPL(nf_conntrack_free);
/* Allocate a new conntrack: we return -ENOMEM if classification
struct sk_buff *skb,
unsigned int dataoff)
{
- struct nf_conn *conntrack;
+ struct nf_conn *ct;
struct nf_conn_help *help;
struct nf_conntrack_tuple repl_tuple;
struct nf_conntrack_expect *exp;
return NULL;
}
- conntrack = nf_conntrack_alloc(tuple, &repl_tuple);
- if (conntrack == NULL || IS_ERR(conntrack)) {
+ ct = nf_conntrack_alloc(tuple, &repl_tuple);
+ if (ct == NULL || IS_ERR(ct)) {
pr_debug("Can't allocate conntrack.\n");
- return (struct nf_conntrack_tuple_hash *)conntrack;
+ return (struct nf_conntrack_tuple_hash *)ct;
}
- if (!l4proto->new(conntrack, skb, dataoff)) {
- nf_conntrack_free(conntrack);
+ if (!l4proto->new(ct, skb, dataoff)) {
+ nf_conntrack_free(ct);
pr_debug("init conntrack: can't track with proto module\n");
return NULL;
}
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
exp = nf_ct_find_expectation(tuple);
if (exp) {
pr_debug("conntrack: expectation arrives ct=%p exp=%p\n",
- conntrack, exp);
+ ct, exp);
/* Welcome, Mr. Bond. We've been expecting you... */
- __set_bit(IPS_EXPECTED_BIT, &conntrack->status);
- conntrack->master = exp->master;
+ __set_bit(IPS_EXPECTED_BIT, &ct->status);
+ ct->master = exp->master;
if (exp->helper) {
- help = nf_ct_helper_ext_add(conntrack, GFP_ATOMIC);
+ help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
if (help)
rcu_assign_pointer(help->helper, exp->helper);
}
#ifdef CONFIG_NF_CONNTRACK_MARK
- conntrack->mark = exp->master->mark;
+ ct->mark = exp->master->mark;
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
- conntrack->secmark = exp->master->secmark;
+ ct->secmark = exp->master->secmark;
#endif
- nf_conntrack_get(&conntrack->master->ct_general);
+ nf_conntrack_get(&ct->master->ct_general);
NF_CT_STAT_INC(expect_new);
} else {
struct nf_conntrack_helper *helper;
helper = __nf_ct_helper_find(&repl_tuple);
if (helper) {
- help = nf_ct_helper_ext_add(conntrack, GFP_ATOMIC);
+ help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
if (help)
rcu_assign_pointer(help->helper, helper);
}
}
/* Overload tuple linked list to put us in unconfirmed list. */
- hlist_add_head(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].hnode,
- &unconfirmed);
+ hlist_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode, &unconfirmed);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
if (exp) {
if (exp->expectfn)
- exp->expectfn(conntrack, exp);
+ exp->expectfn(ct, exp);
nf_ct_expect_put(exp);
}
- return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL];
+ return &ct->tuplehash[IP_CT_DIR_ORIGINAL];
}
/* On success, returns conntrack ptr, sets skb->nfct and ctinfo */
struct nf_conn_help *help = nfct_help(ct);
struct nf_conntrack_helper *helper;
- write_lock_bh(&nf_conntrack_lock);
/* Should be unconfirmed, so not in hash table yet */
NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
if (ct->master || (help && help->expecting != 0))
- goto out;
+ return;
+ rcu_read_lock();
helper = __nf_ct_helper_find(newreply);
if (helper == NULL) {
if (help)
rcu_assign_pointer(help->helper, helper);
out:
- write_unlock_bh(&nf_conntrack_lock);
+ rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply);
NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct);
NF_CT_ASSERT(skb);
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
/* Only update if this is not a fixed timeout */
- if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) {
- write_unlock_bh(&nf_conntrack_lock);
- return;
- }
+ if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status))
+ goto acct;
/* If not in hash table, timer will not be active yet */
if (!nf_ct_is_confirmed(ct)) {
}
}
+acct:
#ifdef CONFIG_NF_CT_ACCT
if (do_acct) {
ct->counters[CTINFO2DIR(ctinfo)].packets++;
}
#endif
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
/* must be unlocked when calling event cache */
if (event)
nf_conntrack_get(nskb->nfct);
}
-static inline int
-do_iter(const struct nf_conntrack_tuple_hash *i,
- int (*iter)(struct nf_conn *i, void *data),
- void *data)
-{
- return iter(nf_ct_tuplehash_to_ctrack(i), data);
-}
-
/* Bring out ya dead! */
static struct nf_conn *
get_next_corpse(int (*iter)(struct nf_conn *i, void *data),
struct nf_conn *ct;
struct hlist_node *n;
- write_lock_bh(&nf_conntrack_lock);
+ spin_lock_bh(&nf_conntrack_lock);
for (; *bucket < nf_conntrack_htable_size; (*bucket)++) {
hlist_for_each_entry(h, n, &nf_conntrack_hash[*bucket], hnode) {
ct = nf_ct_tuplehash_to_ctrack(h);
if (iter(ct, data))
set_bit(IPS_DYING_BIT, &ct->status);
}
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
return NULL;
found:
atomic_inc(&ct->ct_general.use);
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
return ct;
}
return 1;
}
-void nf_ct_free_hashtable(struct hlist_head *hash, int vmalloced, int size)
+void nf_ct_free_hashtable(struct hlist_head *hash, int vmalloced, unsigned int size)
{
if (vmalloced)
vfree(hash);
nf_conntrack_expect_fini();
}
-struct hlist_head *nf_ct_alloc_hashtable(int *sizep, int *vmalloced)
+struct hlist_head *nf_ct_alloc_hashtable(unsigned int *sizep, int *vmalloced)
{
struct hlist_head *hash;
unsigned int size, i;
int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp)
{
- int i, bucket, hashsize, vmalloced;
- int old_vmalloced, old_size;
+ int i, bucket, vmalloced, old_vmalloced;
+ unsigned int hashsize, old_size;
int rnd;
struct hlist_head *hash, *old_hash;
struct nf_conntrack_tuple_hash *h;
if (!nf_conntrack_htable_size)
return param_set_uint(val, kp);
- hashsize = simple_strtol(val, NULL, 0);
+ hashsize = simple_strtoul(val, NULL, 0);
if (!hashsize)
return -EINVAL;
* use a newrandom seed */
get_random_bytes(&rnd, 4);
- write_lock_bh(&nf_conntrack_lock);
+ /* Lookups in the old hash might happen in parallel, which means we
+ * might get false negatives during connection lookup. New connections
+ * created because of a false negative won't make it into the hash
+ * though since that required taking the lock.
+ */
+ spin_lock_bh(&nf_conntrack_lock);
for (i = 0; i < nf_conntrack_htable_size; i++) {
while (!hlist_empty(&nf_conntrack_hash[i])) {
h = hlist_entry(nf_conntrack_hash[i].first,
struct nf_conntrack_tuple_hash, hnode);
- hlist_del(&h->hnode);
+ hlist_del_rcu(&h->hnode);
bucket = __hash_conntrack(&h->tuple, hashsize, rnd);
hlist_add_head(&h->hnode, &hash[bucket]);
}
nf_conntrack_vmalloc = vmalloced;
nf_conntrack_hash = hash;
nf_conntrack_hash_rnd = rnd;
- write_unlock_bh(&nf_conntrack_lock);
+ spin_unlock_bh(&nf_conntrack_lock);
nf_ct_free_hashtable(old_hash, old_vmalloced, old_size);
return 0;
projects / linux-2.6-omap-h63xx.git / blobdiff