}
/**
- * dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet
+ * dccp_wait_for_ccid - Await CCID send permission
* @sk: socket to wait for
- * @skb: current skb to pass on for waiting
- * @delay: sleep timeout in milliseconds (> 0)
- * This function is called by default when the socket is closed, and
- * when a non-zero linger time is set on the socket. For consistency
+ * @delay: timeout in jiffies
+ * This is used by CCIDs which need to delay the send time in process context.
*/
-static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb, int delay)
+static int dccp_wait_for_ccid(struct sock *sk, unsigned long delay)
{
- struct dccp_sock *dp = dccp_sk(sk);
DEFINE_WAIT(wait);
- unsigned long jiffdelay;
- int rc;
-
- do {
- dccp_pr_debug("delayed send by %d msec\n", delay);
- jiffdelay = msecs_to_jiffies(delay);
-
- prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+ long remaining;
- sk->sk_write_pending++;
- release_sock(sk);
- schedule_timeout(jiffdelay);
- lock_sock(sk);
- sk->sk_write_pending--;
+ prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+ sk->sk_write_pending++;
+ release_sock(sk);
- if (sk->sk_err)
- goto do_error;
- if (signal_pending(current))
- goto do_interrupted;
+ remaining = schedule_timeout(delay);
- rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
- } while ((delay = rc) > 0);
-out:
+ lock_sock(sk);
+ sk->sk_write_pending--;
finish_wait(sk->sk_sleep, &wait);
- return rc;
-
-do_error:
- rc = -EPIPE;
- goto out;
-do_interrupted:
- rc = -EINTR;
- goto out;
+
+ if (signal_pending(current) || sk->sk_err)
+ return -1;
+ return remaining;
}
/**
dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC);
}
-void dccp_write_xmit(struct sock *sk, int block)
+/**
+ * dccp_flush_write_queue - Drain queue at end of connection
+ * Since dccp_sendmsg queues packets without waiting for them to be sent, it may
+ * happen that the TX queue is not empty at the end of a connection. We give the
+ * HC-sender CCID a grace period of up to @time_budget jiffies. If this function
+ * returns with a non-empty write queue, it will be purged later.
+ */
+void dccp_flush_write_queue(struct sock *sk, long *time_budget)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct sk_buff *skb;
+ long delay, rc;
+
+ while (*time_budget > 0 && (skb = skb_peek(&sk->sk_write_queue))) {
+ rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
+
+ switch (ccid_packet_dequeue_eval(rc)) {
+ case CCID_PACKET_WILL_DEQUEUE_LATER:
+ /*
+ * If the CCID determines when to send, the next sending
+ * time is unknown or the CCID may not even send again
+ * (e.g. remote host crashes or lost Ack packets).
+ */
+ DCCP_WARN("CCID did not manage to send all packets\n");
+ return;
+ case CCID_PACKET_DELAY:
+ delay = msecs_to_jiffies(rc);
+ if (delay > *time_budget)
+ return;
+ rc = dccp_wait_for_ccid(sk, delay);
+ if (rc < 0)
+ return;
+ *time_budget -= (delay - rc);
+ /* check again if we can send now */
+ break;
+ case CCID_PACKET_SEND_AT_ONCE:
+ dccp_xmit_packet(sk);
+ break;
+ case CCID_PACKET_ERR:
+ skb_dequeue(&sk->sk_write_queue);
+ kfree_skb(skb);
+ dccp_pr_debug("packet discarded due to err=%ld\n", rc);
+ }
+ }
+}
+
+void dccp_write_xmit(struct sock *sk)
{
struct dccp_sock *dp = dccp_sk(sk);
struct sk_buff *skb;
case CCID_PACKET_WILL_DEQUEUE_LATER:
return;
case CCID_PACKET_DELAY:
- if (!block) {
- sk_reset_timer(sk, &dp->dccps_xmit_timer,
- msecs_to_jiffies(rc)+jiffies);
- return;
- }
- rc = dccp_wait_for_ccid(sk, skb, rc);
- if (rc && rc != -EINTR) {
- DCCP_BUG("err=%d after dccp_wait_for_ccid", rc);
- skb_dequeue(&sk->sk_write_queue);
- kfree_skb(skb);
- break;
- }
- /* fall through */
+ sk_reset_timer(sk, &dp->dccps_xmit_timer,
+ jiffies + msecs_to_jiffies(rc));
+ return;
case CCID_PACKET_SEND_AT_ONCE:
dccp_xmit_packet(sk);
break;
DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE;
if (active) {
- dccp_write_xmit(sk, 1);
dccp_skb_entail(sk, skb);
dccp_transmit_skb(sk, skb_clone(skb, prio));
/*
projects / deliverable / linux.git / blobdiff