sctp: remove the old ttl expires policy

The prsctp polices include ttl expires policy already, we should remove
the old ttl expires codes, and just adjust the new polices' codes to be
compatible with the old one for users.

This patch is to remove all the old expires codes, and if prsctp polices
are not set, it will still set msg's expires_at and check the expires in
sctp_check_abandoned.

Note that asoc->prsctp_enable is set by default, so users can't feel any
difference even if they use the old expires api in userspace.

Signed-off-by: Xin Long <[e-mail]>
Acked-by: Marcelo Ricardo Leitner <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/net/sctp/structs.h

···
 	/* Did the messenge fail to send? */
 	int send_error;
 	u8 send_failed:1,
-	   can_abandon:1,   /* can chunks from this message can be abandoned. */
 	   can_delay;	    /* should this message be Nagle delayed */
 };
 

net/sctp/chunk.c

···
 	atomic_set(&msg->refcnt, 1);
 	msg->send_failed = 0;
 	msg->send_error = 0;
-	msg->can_abandon = 0;
 	msg->can_delay = 1;
 	msg->expires_at = 0;
 	INIT_LIST_HEAD(&msg->chunks);
···
 	/* Note: Calculate this outside of the loop, so that all fragments
 	 * have the same expiration.
 	 */
-	if (sinfo->sinfo_timetolive) {
-		/* sinfo_timetolive is in milliseconds */
+	if (asoc->peer.prsctp_capable && sinfo->sinfo_timetolive &&
+	    (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags) ||
+	     !SCTP_PR_POLICY(sinfo->sinfo_flags)))
 		msg->expires_at = jiffies +
 				    msecs_to_jiffies(sinfo->sinfo_timetolive);
-		msg->can_abandon = 1;
-
-		pr_debug("%s: msg:%p expires_at:%ld jiffies:%ld\n", __func__,
-			 msg, msg->expires_at, jiffies);
-	}
-
-	if (asoc->peer.prsctp_capable &&
-	    SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))
-		msg->expires_at =
-			jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);
 
 	/* This is the biggest possible DATA chunk that can fit into
 	 * the packet
···
 /* Check whether this message has expired. */
 int sctp_chunk_abandoned(struct sctp_chunk *chunk)
 {
-	if (!chunk->asoc->peer.prsctp_capable ||
-	    !SCTP_PR_POLICY(chunk->sinfo.sinfo_flags)) {
-		struct sctp_datamsg *msg = chunk->msg;
-
-		if (!msg->can_abandon)
-			return 0;
-
-		if (time_after(jiffies, msg->expires_at))
-			return 1;
-
+	if (!chunk->asoc->peer.prsctp_capable)
 		return 0;
-	}
 
 	if (SCTP_PR_TTL_ENABLED(chunk->sinfo.sinfo_flags) &&
 	    time_after(jiffies, chunk->msg->expires_at)) {
···
 	} else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&
 		   chunk->sent_count > chunk->sinfo.sinfo_timetolive) {
 		chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
+		return 1;
+	} else if (!SCTP_PR_POLICY(chunk->sinfo.sinfo_flags) &&
+		   chunk->msg->expires_at &&
+		   time_after(jiffies, chunk->msg->expires_at)) {
 		return 1;
 	}
 	/* PRIO policy is processed by sendmsg, not here */

net/sctp/output.c

···
 		rwnd = 0;
 
 	asoc->peer.rwnd = rwnd;
-	/* Has been accepted for transmission. */
-	if (!asoc->peer.prsctp_capable)
-		chunk->msg->can_abandon = 0;
 	sctp_chunk_assign_tsn(chunk);
 	sctp_chunk_assign_ssn(chunk);
 }