inetpeer: Add redirect and PMTU discovery cached info.

Validity of the cached PMTU information is indicated by it's
expiration value being non-zero, just as per dst->expires.

The scheme we will use is that we will remember the pre-ICMP value
held in the metrics or route entry, and then at expiration time
we will restore that value.

In this way PMTU expiration does not kill off the cached route as is
done currently.

Redirect information is permanent, or at least until another redirect
is received.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2011-02-09 15:36:47 -08:00
parent 7a71ed899e
commit ddd4aa424b
2 changed files with 13 additions and 7 deletions

View file

@ -43,13 +43,17 @@ struct inet_peer {
*/ */
union { union {
struct { struct {
atomic_t rid; /* Frag reception counter */ atomic_t rid; /* Frag reception counter */
atomic_t ip_id_count; /* IP ID for the next packet */ atomic_t ip_id_count; /* IP ID for the next packet */
__u32 tcp_ts; __u32 tcp_ts;
__u32 tcp_ts_stamp; __u32 tcp_ts_stamp;
u32 metrics[RTAX_MAX]; u32 metrics[RTAX_MAX];
u32 rate_tokens; /* rate limiting for ICMP */ u32 rate_tokens; /* rate limiting for ICMP */
unsigned long rate_last; unsigned long rate_last;
unsigned long pmtu_expires;
u32 pmtu_orig;
u32 pmtu_learned;
struct inetpeer_addr_base redirect_learned;
}; };
struct rcu_head rcu; struct rcu_head rcu;
}; };

View file

@ -515,6 +515,8 @@ struct inet_peer *inet_getpeer(struct inetpeer_addr *daddr, int create)
p->metrics[RTAX_LOCK-1] = INETPEER_METRICS_NEW; p->metrics[RTAX_LOCK-1] = INETPEER_METRICS_NEW;
p->rate_tokens = 0; p->rate_tokens = 0;
p->rate_last = 0; p->rate_last = 0;
p->pmtu_expires = 0;
memset(&p->redirect_learned, 0, sizeof(p->redirect_learned));
INIT_LIST_HEAD(&p->unused); INIT_LIST_HEAD(&p->unused);