inetpeer: Abstract address comparisons.

Now v4 and v6 addresses will both work properly.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2010-11-30 12:08:53 -08:00
parent b534ecf1cd
commit 0266304502

View file

@ -152,6 +152,22 @@ static void unlink_from_unused(struct inet_peer *p)
}
}
static int addr_compare(const inet_peer_address_t *a,
const inet_peer_address_t *b)
{
int i, n = (a->family == AF_INET ? 1 : 4);
for (i = 0; i < n; i++) {
if (a->a6[i] == b->a6[i])
continue;
if (a->a6[i] < b->a6[i])
return -1;
return 1;
}
return 0;
}
/*
* Called with local BH disabled and the pool lock held.
*/
@ -165,9 +181,10 @@ static void unlink_from_unused(struct inet_peer *p)
for (u = rcu_dereference_protected(_base->root, \
lockdep_is_held(&_base->lock)); \
u != peer_avl_empty; ) { \
if (_daddr == u->daddr.a4) \
int cmp = addr_compare(_daddr, &u->daddr); \
if (cmp == 0) \
break; \
if ((__force __u32)_daddr < (__force __u32)u->daddr.a4) \
if (cmp == -1) \
v = &u->avl_left; \
else \
v = &u->avl_right; \
@ -185,13 +202,15 @@ static void unlink_from_unused(struct inet_peer *p)
* But every pointer we follow is guaranteed to be valid thanks to RCU.
* We exit from this function if number of links exceeds PEER_MAXDEPTH
*/
static struct inet_peer *lookup_rcu_bh(__be32 daddr, struct inet_peer_base *base)
static struct inet_peer *lookup_rcu_bh(const inet_peer_address_t *daddr,
struct inet_peer_base *base)
{
struct inet_peer *u = rcu_dereference_bh(base->root);
int count = 0;
while (u != peer_avl_empty) {
if (daddr == u->daddr.a4) {
int cmp = addr_compare(daddr, &u->daddr);
if (cmp == 0) {
/* Before taking a reference, check if this entry was
* deleted, unlink_from_pool() sets refcnt=-1 to make
* distinction between an unused entry (refcnt=0) and
@ -201,7 +220,7 @@ static struct inet_peer *lookup_rcu_bh(__be32 daddr, struct inet_peer_base *base
u = NULL;
return u;
}
if ((__force __u32)daddr < (__force __u32)u->daddr.a4)
if (cmp == -1)
u = rcu_dereference_bh(u->avl_left);
else
u = rcu_dereference_bh(u->avl_right);
@ -354,7 +373,7 @@ static void unlink_from_pool(struct inet_peer *p, struct inet_peer_base *base)
if (atomic_cmpxchg(&p->refcnt, 1, -1) == 1) {
struct inet_peer __rcu **stack[PEER_MAXDEPTH];
struct inet_peer __rcu ***stackptr, ***delp;
if (lookup(p->daddr.a4, stack, base) != p)
if (lookup(&p->daddr, stack, base) != p)
BUG();
delp = stackptr - 1; /* *delp[0] == p */
if (p->avl_left == peer_avl_empty_rcu) {
@ -454,7 +473,7 @@ struct inet_peer *inet_getpeer(inet_peer_address_t *daddr, int create)
* Because of a concurrent writer, we might not find an existing entry.
*/
rcu_read_lock_bh();
p = lookup_rcu_bh(daddr->a4, base);
p = lookup_rcu_bh(daddr, base);
rcu_read_unlock_bh();
if (p) {
@ -469,7 +488,7 @@ struct inet_peer *inet_getpeer(inet_peer_address_t *daddr, int create)
* At least, nodes should be hot in our cache.
*/
spin_lock_bh(&base->lock);
p = lookup(daddr->a4, stack, base);
p = lookup(daddr, stack, base);
if (p != peer_avl_empty) {
atomic_inc(&p->refcnt);
spin_unlock_bh(&base->lock);