sctp: add support for the process of unordered idata

Unordered idata process is more complicated than unordered data:

 - It has to add mid into sctp_stream_out to save the next mid value,
   which is separated from ordered idata's.

 - To support pd for unordered idata, another mid and pd_mode need to
   be added to save the message id and pd state in sctp_stream_in.

 - To make  unordered idata reasm easier, it adds a new event queue
   to save frags for idata.

The patch mostly adds the samilar reasm functions for unordered idata
as ordered idata's, and also adjusts some other codes on assign_mid,
abort_pd and ulpevent_data for idata.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sctp/structs.h

@@ -413,6 +413,14 @@ void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new);
 
 #define sctp_stream_in(asoc, sid) (&(asoc)->stream.in[sid])
 
+/* What is the current MID_uo number for this stream? */
+#define sctp_mid_uo_peek(stream, type, sid) \
+	((stream)->type[sid].mid_uo)
+
+/* Return the next MID_uo number for this stream.  */
+#define sctp_mid_uo_next(stream, type, sid) \
+	((stream)->type[sid].mid_uo++)
+
 /*
  * Pointers to address related SCTP functions.
  * (i.e. things that depend on the address family.)
@@ -1379,8 +1387,9 @@ struct sctp_stream_out {
 		__u32 mid;
 		__u16 ssn;
 	};
-	__u8	state;
+	__u32 mid_uo;
 	struct sctp_stream_out_ext *ext;
+	__u8 state;
 };
 
 struct sctp_stream_in {
@@ -1388,8 +1397,11 @@ struct sctp_stream_in {
 		__u32 mid;
 		__u16 ssn;
 	};
+	__u32 mid_uo;
 	__u32 fsn;
+	__u32 fsn_uo;
 	char pd_mode;
+	char pd_mode_uo;
 };
 
 struct sctp_stream {

include/net/sctp/ulpqueue.h

@@ -45,6 +45,7 @@ struct sctp_ulpq {
 	char pd_mode;
 	struct sctp_association *asoc;
 	struct sk_buff_head reasm;
+	struct sk_buff_head reasm_uo;
 	struct sk_buff_head lobby;
 };
 

net/sctp/socket.c

@@ -201,6 +201,22 @@ static void sctp_for_each_tx_datachunk(struct sctp_association *asoc,
 		cb(chunk);
 }
 
+static void sctp_for_each_rx_skb(struct sctp_association *asoc, struct sock *sk,
+				 void (*cb)(struct sk_buff *, struct sock *))
+
+{
+	struct sk_buff *skb, *tmp;
+
+	sctp_skb_for_each(skb, &asoc->ulpq.lobby, tmp)
+		cb(skb, sk);
+
+	sctp_skb_for_each(skb, &asoc->ulpq.reasm, tmp)
+		cb(skb, sk);
+
+	sctp_skb_for_each(skb, &asoc->ulpq.reasm_uo, tmp)
+		cb(skb, sk);
+}
+
 /* Verify that this is a valid address. */
 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
 				   int len)
@@ -1554,6 +1570,7 @@ static void sctp_close(struct sock *sk, long timeout)
 
 		if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) ||
 		    !skb_queue_empty(&asoc->ulpq.reasm) ||
+		    !skb_queue_empty(&asoc->ulpq.reasm_uo) ||
 		    (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) {
 			struct sctp_chunk *chunk;
 
@@ -8495,11 +8512,7 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
 
 	}
 
-	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp)
-		sctp_skb_set_owner_r_frag(skb, newsk);
-
-	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp)
-		sctp_skb_set_owner_r_frag(skb, newsk);
+	sctp_for_each_rx_skb(assoc, newsk, sctp_skb_set_owner_r_frag);
 
 	/* Set the type of socket to indicate that it is peeled off from the
 	 * original UDP-style socket or created with the accept() call on a

net/sctp/ulpqueue.c

@@ -60,6 +60,7 @@ struct sctp_ulpq *sctp_ulpq_init(struct sctp_ulpq *ulpq,
 
 	ulpq->asoc = asoc;
 	skb_queue_head_init(&ulpq->reasm);
+	skb_queue_head_init(&ulpq->reasm_uo);
 	skb_queue_head_init(&ulpq->lobby);
 	ulpq->pd_mode  = 0;
 
@@ -83,6 +84,10 @@ void sctp_ulpq_flush(struct sctp_ulpq *ulpq)
 		sctp_ulpevent_free(event);
 	}
 
+	while ((skb = __skb_dequeue(&ulpq->reasm_uo)) != NULL) {
+		event = sctp_skb2event(skb);
+		sctp_ulpevent_free(event);
+	}
 }
 
 /* Dispose of a ulpqueue.  */