int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
struct dn_scp *scp = DN_SK(sk);
struct sk_buff *skb2, *n, *ack = NULL;
int wakeup = 0;
int try_retrans = 0;
unsigned long reftime = cb->stamp;
unsigned long pkttime;
unsigned short xmit_count;
unsigned short segnum;
skb_queue_walk_safe(q, skb2, n) {
struct dn_skb_cb *cb2 = DN_SKB_CB(skb2);
if (dn_before_or_equal(cb2->segnum, acknum))
ack = skb2;
if (ack == NULL)
continue;
try_retrans = 0;
wakeup = 1;
pkttime = cb2->stamp;
xmit_count = cb2->xmit_count;
segnum = cb2->segnum;
skb_unlink(ack, q);
kfree_skb(ack);
ack = NULL;
WARN_ON(xmit_count == 0);
if (xmit_count == 1) {
if (dn_equal(segnum, acknum))
dn_nsp_rtt(sk, (long)(pkttime - reftime));
if (scp->snd_window < scp->max_window)
scp->snd_window++;
}
if (xmit_count > 1)
try_retrans = 1;
}
if (try_retrans)
dn_nsp_output(sk);
return wakeup;
}
int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
struct dn_scp *scp = DN_SK(sk);
struct sk_buff *skb2, *n, *ack = NULL;
int wakeup = 0;
int try_retrans = 0;
unsigned long reftime = cb->stamp;
unsigned long pkttime;
unsigned short xmit_count;
unsigned short segnum;
skb_queue_walk_safe(q, skb2, n) {
struct dn_skb_cb *cb2 = DN_SKB_CB(skb2);
if (dn_before_or_equal(cb2->segnum, acknum))
ack = skb2;
/* printk(KERN_DEBUG "ack: %s %04x %04x\n", ack ? "ACK" : "SKIP", (int)cb2->segnum, (int)acknum); */
if (ack == NULL)
continue;
/* printk(KERN_DEBUG "check_xmit_queue: %04x, %d\n", acknum, cb2->xmit_count); */
/* Does _last_ packet acked have xmit_count > 1 */
try_retrans = 0;
/* Remember to wake up the sending process */
wakeup = 1;
/* Keep various statistics */
pkttime = cb2->stamp;
xmit_count = cb2->xmit_count;
segnum = cb2->segnum;
/* Remove and drop ack'ed packet */
skb_unlink(ack, q);
kfree_skb(ack);
ack = NULL;
/*
* We don't expect to see acknowledgements for packets we
* haven't sent yet.
*/
WARN_ON(xmit_count == 0);
/*
* If the packet has only been sent once, we can use it
* to calculate the RTT and also open the window a little
* further.
*/
if (xmit_count == 1) {
if (dn_equal(segnum, acknum))
dn_nsp_rtt(sk, (long)(pkttime - reftime));
if (scp->snd_window < scp->max_window)
scp->snd_window++;
}
/*
* Packet has been sent more than once. If this is the last
* packet to be acknowledged then we want to send the next
* packet in the send queue again (assumes the remote host does
* go-back-N error control).
*/
if (xmit_count > 1)
try_retrans = 1;
}
if (try_retrans)
dn_nsp_output(sk);
return wakeup;
}