29 files changed, 1777 insertions, 1582 deletions

diff --git a/net/dccp/Kconfig b/net/dccp/Kconfig
index 0549e4719b1..7aa2a7acc7e 100644
--- a/net/dccp/Kconfig
+++ b/net/dccp/Kconfig
@@ -1,6 +1,7 @@
 menuconfig IP_DCCP
 	tristate "The DCCP Protocol (EXPERIMENTAL)"
 	depends on INET && EXPERIMENTAL
+	select IP_DCCP_CCID2
 	---help---
 	  Datagram Congestion Control Protocol (RFC 4340)
 
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index 83378f379f7..6de4bd195d2 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -30,7 +30,7 @@ static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
 			kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
 
 	if (avr != NULL)
-		INIT_LIST_HEAD(&avr->dccpavr_node);
+		INIT_LIST_HEAD(&avr->avr_node);
 
 	return avr;
 }
@@ -40,7 +40,7 @@ static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
 	if (unlikely(avr == NULL))
 		return;
 	/* Check if deleting a linked record */
-	WARN_ON(!list_empty(&avr->dccpavr_node));
+	WARN_ON(!list_empty(&avr->avr_node));
 	kmem_cache_free(dccp_ackvec_record_slab, avr);
 }
 
@@ -52,16 +52,15 @@ static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
 	 * just add the AVR at the head of the list.
 	 * -sorbo.
 	 */
-	if (!list_empty(&av->dccpav_records)) {
+	if (!list_empty(&av->av_records)) {
 		const struct dccp_ackvec_record *head =
-					list_entry(av->dccpav_records.next,
+					list_entry(av->av_records.next,
 						   struct dccp_ackvec_record,
-						   dccpavr_node);
-		BUG_ON(before48(avr->dccpavr_ack_seqno,
-				head->dccpavr_ack_seqno));
+						   avr_node);
+		BUG_ON(before48(avr->avr_ack_seqno, head->avr_ack_seqno));
 	}
 
-	list_add(&avr->dccpavr_node, &av->dccpav_records);
+	list_add(&avr->avr_node, &av->av_records);
 }
 
 int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
@@ -69,9 +68,8 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 	struct dccp_sock *dp = dccp_sk(sk);
 	struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
 	/* Figure out how many options do we need to represent the ackvec */
-	const u16 nr_opts = DIV_ROUND_UP(av->dccpav_vec_len,
-					 DCCP_MAX_ACKVEC_OPT_LEN);
-	u16 len = av->dccpav_vec_len + 2 * nr_opts, i;
+	const u16 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_MAX_ACKVEC_OPT_LEN);
+	u16 len = av->av_vec_len + 2 * nr_opts, i;
 	u32 elapsed_time;
 	const unsigned char *tail, *from;
 	unsigned char *to;
@@ -81,7 +79,7 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
 		return -1;
 
-	delta = ktime_us_delta(ktime_get_real(), av->dccpav_time);
+	delta = ktime_us_delta(ktime_get_real(), av->av_time);
 	elapsed_time = delta / 10;
 
 	if (elapsed_time != 0 &&
@@ -95,9 +93,9 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 	DCCP_SKB_CB(skb)->dccpd_opt_len += len;
 
 	to   = skb_push(skb, len);
-	len  = av->dccpav_vec_len;
-	from = av->dccpav_buf + av->dccpav_buf_head;
-	tail = av->dccpav_buf + DCCP_MAX_ACKVEC_LEN;
+	len  = av->av_vec_len;
+	from = av->av_buf + av->av_buf_head;
+	tail = av->av_buf + DCCP_MAX_ACKVEC_LEN;
 
 	for (i = 0; i < nr_opts; ++i) {
 		int copylen = len;
@@ -116,7 +114,7 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 			to	+= tailsize;
 			len	-= tailsize;
 			copylen	-= tailsize;
-			from	= av->dccpav_buf;
+			from	= av->av_buf;
 		}
 
 		memcpy(to, from, copylen);
@@ -134,19 +132,19 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 	 *	buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
 	 *	equal buf_nonce.
 	 */
-	avr->dccpavr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
-	avr->dccpavr_ack_ptr   = av->dccpav_buf_head;
-	avr->dccpavr_ack_ackno = av->dccpav_buf_ackno;
-	avr->dccpavr_ack_nonce = av->dccpav_buf_nonce;
-	avr->dccpavr_sent_len  = av->dccpav_vec_len;
+	avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+	avr->avr_ack_ptr   = av->av_buf_head;
+	avr->avr_ack_ackno = av->av_buf_ackno;
+	avr->avr_ack_nonce = av->av_buf_nonce;
+	avr->avr_sent_len  = av->av_vec_len;
 
 	dccp_ackvec_insert_avr(av, avr);
 
 	dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
 		      "ack_ackno=%llu\n",
-		      dccp_role(sk), avr->dccpavr_sent_len,
-		      (unsigned long long)avr->dccpavr_ack_seqno,
-		      (unsigned long long)avr->dccpavr_ack_ackno);
+		      dccp_role(sk), avr->avr_sent_len,
+		      (unsigned long long)avr->avr_ack_seqno,
+		      (unsigned long long)avr->avr_ack_ackno);
 	return 0;
 }
 
@@ -155,12 +153,12 @@ struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
 	struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority);
 
 	if (av != NULL) {
-		av->dccpav_buf_head	= DCCP_MAX_ACKVEC_LEN - 1;
-		av->dccpav_buf_ackno	= UINT48_MAX + 1;
-		av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
-		av->dccpav_time	     = ktime_set(0, 0);
-		av->dccpav_vec_len	= 0;
-		INIT_LIST_HEAD(&av->dccpav_records);
+		av->av_buf_head	 = DCCP_MAX_ACKVEC_LEN - 1;
+		av->av_buf_ackno = UINT48_MAX + 1;
+		av->av_buf_nonce = 0;
+		av->av_time	 = ktime_set(0, 0);
+		av->av_vec_len	 = 0;
+		INIT_LIST_HEAD(&av->av_records);
 	}
 
 	return av;
@@ -171,12 +169,11 @@ void dccp_ackvec_free(struct dccp_ackvec *av)
 	if (unlikely(av == NULL))
 		return;
 
-	if (!list_empty(&av->dccpav_records)) {
+	if (!list_empty(&av->av_records)) {
 		struct dccp_ackvec_record *avr, *next;
 
-		list_for_each_entry_safe(avr, next, &av->dccpav_records,
-					 dccpavr_node) {
-			list_del_init(&avr->dccpavr_node);
+		list_for_each_entry_safe(avr, next, &av->av_records, avr_node) {
+			list_del_init(&avr->avr_node);
 			dccp_ackvec_record_delete(avr);
 		}
 	}
@@ -187,13 +184,13 @@ void dccp_ackvec_free(struct dccp_ackvec *av)
 static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
 				   const u32 index)
 {
-	return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK;
+	return av->av_buf[index] & DCCP_ACKVEC_STATE_MASK;
 }
 
 static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
 				 const u32 index)
 {
-	return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK;
+	return av->av_buf[index] & DCCP_ACKVEC_LEN_MASK;
 }
 
 /*
@@ -208,29 +205,29 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
 	unsigned int gap;
 	long new_head;
 
-	if (av->dccpav_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
+	if (av->av_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
 		return -ENOBUFS;
 
 	gap	 = packets - 1;
-	new_head = av->dccpav_buf_head - packets;
+	new_head = av->av_buf_head - packets;
 
 	if (new_head < 0) {
 		if (gap > 0) {
-			memset(av->dccpav_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
+			memset(av->av_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
 			       gap + new_head + 1);
 			gap = -new_head;
 		}
 		new_head += DCCP_MAX_ACKVEC_LEN;
 	}
 
-	av->dccpav_buf_head = new_head;
+	av->av_buf_head = new_head;
 
 	if (gap > 0)
-		memset(av->dccpav_buf + av->dccpav_buf_head + 1,
+		memset(av->av_buf + av->av_buf_head + 1,
 		       DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
 
-	av->dccpav_buf[av->dccpav_buf_head] = state;
-	av->dccpav_vec_len += packets;
+	av->av_buf[av->av_buf_head] = state;
+	av->av_vec_len += packets;
 	return 0;
 }
 
@@ -243,7 +240,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
 	/*
 	 * Check at the right places if the buffer is full, if it is, tell the
 	 * caller to start dropping packets till the HC-Sender acks our ACK
-	 * vectors, when we will free up space in dccpav_buf.
+	 * vectors, when we will free up space in av_buf.
 	 *
 	 * We may well decide to do buffer compression, etc, but for now lets
 	 * just drop.
@@ -263,22 +260,20 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
 	 */
 
 	/* See if this is the first ackno being inserted */
-	if (av->dccpav_vec_len == 0) {
-		av->dccpav_buf[av->dccpav_buf_head] = state;
-		av->dccpav_vec_len = 1;
-	} else if (after48(ackno, av->dccpav_buf_ackno)) {
-		const u64 delta = dccp_delta_seqno(av->dccpav_buf_ackno,
-						   ackno);
+	if (av->av_vec_len == 0) {
+		av->av_buf[av->av_buf_head] = state;
+		av->av_vec_len = 1;
+	} else if (after48(ackno, av->av_buf_ackno)) {
+		const u64 delta = dccp_delta_seqno(av->av_buf_ackno, ackno);
 
 		/*
 		 * Look if the state of this packet is the same as the
 		 * previous ackno and if so if we can bump the head len.
 		 */
 		if (delta == 1 &&
-		    dccp_ackvec_state(av, av->dccpav_buf_head) == state &&
-		    (dccp_ackvec_len(av, av->dccpav_buf_head) <
-		     DCCP_ACKVEC_LEN_MASK))
-			av->dccpav_buf[av->dccpav_buf_head]++;
+		    dccp_ackvec_state(av, av->av_buf_head) == state &&
+		    dccp_ackvec_len(av, av->av_buf_head) < DCCP_ACKVEC_LEN_MASK)
+			av->av_buf[av->av_buf_head]++;
 		else if (dccp_ackvec_set_buf_head_state(av, delta, state))
 			return -ENOBUFS;
 	} else {
@@ -290,14 +285,14 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
 		 *	the byte corresponding to S. (Indexing structures
 		 *	could reduce the complexity of this scan.)
 		 */
-		u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno);
-		u32 index = av->dccpav_buf_head;
+		u64 delta = dccp_delta_seqno(ackno, av->av_buf_ackno);
+		u32 index = av->av_buf_head;
 
 		while (1) {
 			const u8 len = dccp_ackvec_len(av, index);
 			const u8 state = dccp_ackvec_state(av, index);
 			/*
-			 * valid packets not yet in dccpav_buf have a reserved
+			 * valid packets not yet in av_buf have a reserved
 			 * entry, with a len equal to 0.
 			 */
 			if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
@@ -305,7 +300,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
 							 reserved seat! */
 				dccp_pr_debug("Found %llu reserved seat!\n",
 					      (unsigned long long)ackno);
-				av->dccpav_buf[index] = state;
+				av->av_buf[index] = state;
 				goto out;
 			}
 			/* len == 0 means one packet */
@@ -318,8 +313,8 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
 		}
 	}
 
-	av->dccpav_buf_ackno = ackno;
-	av->dccpav_time = ktime_get_real();
+	av->av_buf_ackno = ackno;
+	av->av_time = ktime_get_real();
 out:
 	return 0;
 
@@ -349,9 +344,9 @@ void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len)
 
 void dccp_ackvec_print(const struct dccp_ackvec *av)
 {
-	dccp_ackvector_print(av->dccpav_buf_ackno,
-			     av->dccpav_buf + av->dccpav_buf_head,
-			     av->dccpav_vec_len);
+	dccp_ackvector_print(av->av_buf_ackno,
+			     av->av_buf + av->av_buf_head,
+			     av->av_vec_len);
 }
 #endif
 
@@ -361,17 +356,15 @@ static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
 	struct dccp_ackvec_record *next;
 
 	/* sort out vector length */
-	if (av->dccpav_buf_head <= avr->dccpavr_ack_ptr)
-		av->dccpav_vec_len = avr->dccpavr_ack_ptr - av->dccpav_buf_head;
+	if (av->av_buf_head <= avr->avr_ack_ptr)
+		av->av_vec_len = avr->avr_ack_ptr - av->av_buf_head;
 	else
-		av->dccpav_vec_len = DCCP_MAX_ACKVEC_LEN - 1
-				     - av->dccpav_buf_head
-				     + avr->dccpavr_ack_ptr;
+		av->av_vec_len = DCCP_MAX_ACKVEC_LEN - 1 -
+				 av->av_buf_head + avr->avr_ack_ptr;
 
 	/* free records */
-	list_for_each_entry_safe_from(avr, next, &av->dccpav_records,
-				      dccpavr_node) {
-		list_del_init(&avr->dccpavr_node);
+	list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) {
+		list_del_init(&avr->avr_node);
 		dccp_ackvec_record_delete(avr);
 	}
 }
@@ -386,16 +379,16 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
 	 * windows. We will be receiving ACKs for stuff we sent a while back
 	 * -sorbo.
 	 */
-	list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) {
-		if (ackno == avr->dccpavr_ack_seqno) {
+	list_for_each_entry_reverse(avr, &av->av_records, avr_node) {
+		if (ackno == avr->avr_ack_seqno) {
 			dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
 				      "ack_ackno=%llu, ACKED!\n",
 				      dccp_role(sk), 1,
-				      (unsigned long long)avr->dccpavr_ack_seqno,
-				      (unsigned long long)avr->dccpavr_ack_ackno);
+				      (unsigned long long)avr->avr_ack_seqno,
+				      (unsigned long long)avr->avr_ack_ackno);
 			dccp_ackvec_throw_record(av, avr);
 			break;
-		} else if (avr->dccpavr_ack_seqno > ackno)
+		} else if (avr->avr_ack_seqno > ackno)
 			break; /* old news */
 	}
 }
@@ -409,7 +402,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
 	struct dccp_ackvec_record *avr;
 
 	/* Check if we actually sent an ACK vector */
-	if (list_empty(&av->dccpav_records))
+	if (list_empty(&av->av_records))
 		return;
 
 	i = len;
@@ -418,8 +411,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
 	 * I think it might be more efficient to work backwards. See comment on
 	 * rcv_ackno. -sorbo.
 	 */
-	avr = list_entry(av->dccpav_records.next, struct dccp_ackvec_record,
-			 dccpavr_node);
+	avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node);
 	while (i--) {
 		const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
 		u64 ackno_end_rl;
@@ -430,15 +422,14 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
 		 * If our AVR sequence number is greater than the ack, go
 		 * forward in the AVR list until it is not so.
 		 */
-		list_for_each_entry_from(avr, &av->dccpav_records,
-					 dccpavr_node) {
-			if (!after48(avr->dccpavr_ack_seqno, *ackno))
+		list_for_each_entry_from(avr, &av->av_records, avr_node) {
+			if (!after48(avr->avr_ack_seqno, *ackno))
 				goto found;
 		}
-		/* End of the dccpav_records list, not found, exit */
+		/* End of the av_records list, not found, exit */
 		break;
 found:
-		if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, *ackno)) {
+		if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) {
 			const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
 			if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
 				dccp_pr_debug("%s ACK vector 0, len=%d, "
@@ -446,9 +437,9 @@ found:
 					      "ACKED!\n",
 					      dccp_role(sk), len,
 					      (unsigned long long)
-					      avr->dccpavr_ack_seqno,
+					      avr->avr_ack_seqno,
 					      (unsigned long long)
-					      avr->dccpavr_ack_ackno);
+					      avr->avr_ack_ackno);
 				dccp_ackvec_throw_record(av, avr);
 				break;
 			}
diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h
index 9671ecd17e0..bcb64fb4ace 100644
--- a/net/dccp/ackvec.h
+++ b/net/dccp/ackvec.h
@@ -32,54 +32,54 @@
  *
  * This data structure is the one defined in RFC 4340, Appendix A.
  *
- * @dccpav_buf_head - circular buffer head
- * @dccpav_buf_tail - circular buffer tail
- * @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the
- * 		       buffer (i.e. %dccpav_buf_head)
- * @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
+ * @av_buf_head - circular buffer head
+ * @av_buf_tail - circular buffer tail
+ * @av_buf_ackno - ack # of the most recent packet acknowledgeable in the
+ *		       buffer (i.e. %av_buf_head)
+ * @av_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
  * 		       by the buffer with State 0
  *
  * Additionally, the HC-Receiver must keep some information about the
  * Ack Vectors it has recently sent. For each packet sent carrying an
  * Ack Vector, it remembers four variables:
  *
- * @dccpav_records - list of dccp_ackvec_record
- * @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
+ * @av_records - list of dccp_ackvec_record
+ * @av_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
  *
- * @dccpav_time		- the time in usecs
- * @dccpav_buf - circular buffer of acknowledgeable packets
+ * @av_time - the time in usecs
+ * @av_buf - circular buffer of acknowledgeable packets
  */
 struct dccp_ackvec {
-	u64		dccpav_buf_ackno;
-	struct list_head dccpav_records;
-	ktime_t		dccpav_time;
-	u16		dccpav_buf_head;
-	u16		dccpav_vec_len;
-	u8		dccpav_buf_nonce;
-	u8		dccpav_ack_nonce;
-	u8		dccpav_buf[DCCP_MAX_ACKVEC_LEN];
+	u64			av_buf_ackno;
+	struct list_head	av_records;
+	ktime_t			av_time;
+	u16			av_buf_head;
+	u16			av_vec_len;
+	u8			av_buf_nonce;
+	u8			av_ack_nonce;
+	u8			av_buf[DCCP_MAX_ACKVEC_LEN];
 };
 
 /** struct dccp_ackvec_record - ack vector record
  *
  * ACK vector record as defined in Appendix A of spec.
  *
- * The list is sorted by dccpavr_ack_seqno
+ * The list is sorted by avr_ack_seqno
  *
- * @dccpavr_node - node in dccpav_records
- * @dccpavr_ack_seqno - sequence number of the packet this record was sent on
- * @dccpavr_ack_ackno - sequence number being acknowledged
- * @dccpavr_ack_ptr - pointer into dccpav_buf where this record starts
- * @dccpavr_ack_nonce - dccpav_ack_nonce at the time this record was sent
- * @dccpavr_sent_len - length of the record in dccpav_buf
+ * @avr_node - node in av_records
+ * @avr_ack_seqno - sequence number of the packet this record was sent on
+ * @avr_ack_ackno - sequence number being acknowledged
+ * @avr_ack_ptr - pointer into av_buf where this record starts
+ * @avr_ack_nonce - av_ack_nonce at the time this record was sent
+ * @avr_sent_len - lenght of the record in av_buf
  */
 struct dccp_ackvec_record {
-	struct list_head dccpavr_node;
-	u64		 dccpavr_ack_seqno;
-	u64		 dccpavr_ack_ackno;
-	u16		 dccpavr_ack_ptr;
-	u16		 dccpavr_sent_len;
-	u8		 dccpavr_ack_nonce;
+	struct list_head avr_node;
+	u64		 avr_ack_seqno;
+	u64		 avr_ack_ackno;
+	u16		 avr_ack_ptr;
+	u16		 avr_sent_len;
+	u8		 avr_ack_nonce;
 };
 
 struct sock;
@@ -105,7 +105,7 @@ extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
 
 static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
 {
-	return av->dccpav_vec_len;
+	return av->av_vec_len;
 }
 #else /* CONFIG_IP_DCCP_ACKVEC */
 static inline int dccp_ackvec_init(void)
diff --git a/net/dccp/ccid.c b/net/dccp/ccid.c
index c45088b5e6f..4809753d12a 100644
--- a/net/dccp/ccid.c
+++ b/net/dccp/ccid.c
@@ -92,15 +92,15 @@ int ccid_register(struct ccid_operations *ccid_ops)
 
 	ccid_ops->ccid_hc_rx_slab =
 			ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size,
-					       "%s_hc_rx_sock",
-					       ccid_ops->ccid_name);
+					       "ccid%u_hc_rx_sock",
+					       ccid_ops->ccid_id);
 	if (ccid_ops->ccid_hc_rx_slab == NULL)
 		goto out;
 
 	ccid_ops->ccid_hc_tx_slab =
 			ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size,
-					       "%s_hc_tx_sock",
-					       ccid_ops->ccid_name);
+					       "ccid%u_hc_tx_sock",
+					       ccid_ops->ccid_id);
 	if (ccid_ops->ccid_hc_tx_slab == NULL)
 		goto out_free_rx_slab;
 
diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h
index c65cb2453e4..fdeae7b5731 100644
--- a/net/dccp/ccid.h
+++ b/net/dccp/ccid.h
@@ -23,14 +23,37 @@
 
 struct tcp_info;
 
+/**
+ *  struct ccid_operations  -  Interface to Congestion-Control Infrastructure
+ *
+ *  @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
+ *  @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
+ *  @ccid_name: alphabetical identifier string for @ccid_id
+ *  @ccid_owner: module which implements/owns this CCID
+ *  @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
+ *  @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
+ *
+ *  @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
+ *  @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
+ *  @ccid_hc_rx_packet_recv: implements the HC-receiver side
+ *  @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
+ *  @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
+ *  @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
+ *  @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
+ *  @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
+ *  @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
+ *  @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
+ */
 struct ccid_operations {
-	unsigned char	ccid_id;
-	const char	*ccid_name;
-	struct module	*ccid_owner;
-	struct kmem_cache	*ccid_hc_rx_slab;
-	__u32		ccid_hc_rx_obj_size;
-	struct kmem_cache	*ccid_hc_tx_slab;
-	__u32		ccid_hc_tx_obj_size;
+	unsigned char		ccid_id;
+	__u32			ccid_ccmps;
+	const char		*ccid_name;
+	struct module		*ccid_owner;
+	struct kmem_cache	*ccid_hc_rx_slab,
+				*ccid_hc_tx_slab;
+	__u32			ccid_hc_rx_obj_size,
+				ccid_hc_tx_obj_size;
+	/* Interface Routines */
 	int		(*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
 	int		(*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
 	void		(*ccid_hc_rx_exit)(struct sock *sk);
diff --git a/net/dccp/ccids/Kconfig b/net/dccp/ccids/Kconfig
index 80f46988769..12275943eab 100644
--- a/net/dccp/ccids/Kconfig
+++ b/net/dccp/ccids/Kconfig
@@ -1,9 +1,8 @@
 menu "DCCP CCIDs Configuration (EXPERIMENTAL)"
-	depends on IP_DCCP && EXPERIMENTAL
+	depends on EXPERIMENTAL
 
 config IP_DCCP_CCID2
 	tristate "CCID2 (TCP-Like) (EXPERIMENTAL)"
-	depends on IP_DCCP
 	def_tristate IP_DCCP
 	select IP_DCCP_ACKVEC
 	---help---
@@ -20,18 +19,9 @@ config IP_DCCP_CCID2
 	  to the user.  For example, a hypothetical application that
 	  transferred files over DCCP, using application-level retransmissions
 	  for lost packets, would prefer CCID 2 to CCID 3.  On-line games may
-	  also prefer CCID 2.
+	  also prefer CCID 2.  See RFC 4341 for further details.
 
-	  CCID 2 is further described in RFC 4341,
-	  http://www.ietf.org/rfc/rfc4341.txt
-
-	  This text was extracted from RFC 4340 (sec. 10.1),
-	  http://www.ietf.org/rfc/rfc4340.txt
-
-	  To compile this CCID as a module, choose M here: the module will be
-	  called dccp_ccid2.
-
-	  If in doubt, say M.
+	  CCID2 is the default CCID used by DCCP.
 
 config IP_DCCP_CCID2_DEBUG
 	  bool "CCID2 debugging messages"
@@ -47,8 +37,8 @@ config IP_DCCP_CCID2_DEBUG
 
 config IP_DCCP_CCID3
 	tristate "CCID3 (TCP-Friendly) (EXPERIMENTAL)"
-	depends on IP_DCCP
 	def_tristate IP_DCCP
+	select IP_DCCP_TFRC_LIB
 	---help---
 	  CCID 3 denotes TCP-Friendly Rate Control (TFRC), an equation-based
 	  rate-controlled congestion control mechanism.  TFRC is designed to
@@ -74,10 +64,6 @@ config IP_DCCP_CCID3
 
 	  If in doubt, say M.
 
-config IP_DCCP_TFRC_LIB
-	depends on IP_DCCP_CCID3
-	def_tristate IP_DCCP_CCID3
-
 config IP_DCCP_CCID3_DEBUG
 	  bool "CCID3 debugging messages"
 	  depends on IP_DCCP_CCID3
@@ -121,5 +107,13 @@ config IP_DCCP_CCID3_RTO
 	    is serious network congestion: experimenting with larger values should
 	    therefore not be performed on WANs.
 
+config IP_DCCP_TFRC_LIB
+	tristate
+	default n
+
+config IP_DCCP_TFRC_DEBUG
+	bool
+	depends on IP_DCCP_TFRC_LIB
+	default y if IP_DCCP_CCID3_DEBUG
 
 endmenu
diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c
index d694656b880..b5b52ebb269 100644
--- a/net/dccp/ccids/ccid2.c
+++ b/net/dccp/ccids/ccid2.c
@@ -24,9 +24,6 @@
 
 /*
  * This implementation should follow RFC 4341
- *
- * BUGS:
- * - sequence number wrapping
  */
 
 #include "../ccid.h"
@@ -129,50 +126,35 @@ static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
 {
 	struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
 
-	ccid2_pr_debug("pipe=%d cwnd=%d\n", hctx->ccid2hctx_pipe,
-		       hctx->ccid2hctx_cwnd);
-
-	if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd) {
-		/* OK we can send... make sure previous packet was sent off */
-		if (!hctx->ccid2hctx_sendwait) {
-			hctx->ccid2hctx_sendwait = 1;
-			return 0;
-		}
-	}
+	if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd)
+		return 0;
 
 	return 1; /* XXX CCID should dequeue when ready instead of polling */
 }
 
-static void ccid2_change_l_ack_ratio(struct sock *sk, int val)
+static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val)
 {
 	struct dccp_sock *dp = dccp_sk(sk);
+	u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->ccid2hctx_cwnd, 2);
+
 	/*
-	 * XXX I don't really agree with val != 2.  If cwnd is 1, ack ratio
-	 * should be 1... it shouldn't be allowed to become 2.
-	 * -sorbo.
+	 * Ensure that Ack Ratio does not exceed ceil(cwnd/2), which is (2) from
+	 * RFC 4341, 6.1.2. We ignore the statement that Ack Ratio 2 is always
+	 * acceptable since this causes starvation/deadlock whenever cwnd < 2.
+	 * The same problem arises when Ack Ratio is 0 (ie. Ack Ratio disabled).
 	 */
-	if (val != 2) {
-		const struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
-		int max = hctx->ccid2hctx_cwnd / 2;
-
-		/* round up */
-		if (hctx->ccid2hctx_cwnd & 1)
-			max++;
-
-		if (val > max)
-			val = max;
+	if (val == 0 || val > max_ratio) {
+		DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio);
+		val = max_ratio;
 	}
+	if (val > 0xFFFF)		/* RFC 4340, 11.3 */
+		val = 0xFFFF;
 
-	ccid2_pr_debug("changing local ack ratio to %d\n", val);
-	WARN_ON(val <= 0);
-	dp->dccps_l_ack_ratio = val;
-}
+	if (val == dp->dccps_l_ack_ratio)
+		return;
 
-static void ccid2_change_cwnd(struct ccid2_hc_tx_sock *hctx, u32 val)
-{
-	/* XXX do we need to change ack ratio? */
-	hctx->ccid2hctx_cwnd = val? : 1;
-	ccid2_pr_debug("changed cwnd to %u\n", hctx->ccid2hctx_cwnd);
+	ccid2_pr_debug("changing local ack ratio to %u\n", val);
+	dp->dccps_l_ack_ratio = val;
 }
 
 static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val)
@@ -181,11 +163,6 @@ static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val)
 	hctx->ccid2hctx_srtt = val;
 }
 
-static void ccid2_change_pipe(struct ccid2_hc_tx_sock *hctx, long val)
-{
-	hctx->ccid2hctx_pipe = val;
-}
-
 static void ccid2_start_rto_timer(struct sock *sk);
 
 static void ccid2_hc_tx_rto_expire(unsigned long data)
@@ -215,21 +192,17 @@ static void ccid2_hc_tx_rto_expire(unsigned long data)
 	ccid2_start_rto_timer(sk);
 
 	/* adjust pipe, cwnd etc */
-	ccid2_change_pipe(hctx, 0);
-	hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd >> 1;
+	hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd / 2;
 	if (hctx->ccid2hctx_ssthresh < 2)
 		hctx->ccid2hctx_ssthresh = 2;
-	ccid2_change_cwnd(hctx, 1);
+	hctx->ccid2hctx_cwnd	 = 1;
+	hctx->ccid2hctx_pipe	 = 0;
 
 	/* clear state about stuff we sent */
-	hctx->ccid2hctx_seqt	= hctx->ccid2hctx_seqh;
-	hctx->ccid2hctx_ssacks	= 0;
-	hctx->ccid2hctx_acks	= 0;
-	hctx->ccid2hctx_sent	= 0;
+	hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
+	hctx->ccid2hctx_packets_acked = 0;
 
 	/* clear ack ratio state. */
-	hctx->ccid2hctx_arsent	 = 0;
-	hctx->ccid2hctx_ackloss  = 0;
 	hctx->ccid2hctx_rpseq	 = 0;
 	hctx->ccid2hctx_rpdupack = -1;
 	ccid2_change_l_ack_ratio(sk, 1);
@@ -255,23 +228,10 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
 	struct dccp_sock *dp = dccp_sk(sk);
 	struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
 	struct ccid2_seq *next;
-	u64 seq;
-
-	ccid2_hc_tx_check_sanity(hctx);
 
-	BUG_ON(!hctx->ccid2hctx_sendwait);
-	hctx->ccid2hctx_sendwait = 0;
-	ccid2_change_pipe(hctx, hctx->ccid2hctx_pipe + 1);
-	BUG_ON(hctx->ccid2hctx_pipe < 0);
+	hctx->ccid2hctx_pipe++;
 
-	/* There is an issue.  What if another packet is sent between
-	 * packet_send() and packet_sent().  Then the sequence number would be
-	 * wrong.
-	 * -sorbo.
-	 */
-	seq = dp->dccps_gss;
-
-	hctx->ccid2hctx_seqh->ccid2s_seq   = seq;
+	hctx->ccid2hctx_seqh->ccid2s_seq   = dp->dccps_gss;
 	hctx->ccid2hctx_seqh->ccid2s_acked = 0;
 	hctx->ccid2hctx_seqh->ccid2s_sent  = jiffies;
 
@@ -291,8 +251,26 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
 	ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd,
 		       hctx->ccid2hctx_pipe);
 
-	hctx->ccid2hctx_sent++;
-
+	/*
+	 * FIXME: The code below is broken and the variables have been removed
+	 * from the socket struct. The `ackloss' variable was always set to 0,
+	 * and with arsent there are several problems:
+	 *  (i) it doesn't just count the number of Acks, but all sent packets;
+	 *  (ii) it is expressed in # of packets, not # of windows, so the
+	 *  comparison below uses the wrong formula: Appendix A of RFC 4341
+	 *  comes up with the number K = cwnd / (R^2 - R) of consecutive windows
+	 *  of data with no lost or marked Ack packets. If arsent were the # of
+	 *  consecutive Acks received without loss, then Ack Ratio needs to be
+	 *  decreased by 1 when
+	 *	      arsent >=  K * cwnd / R  =  cwnd^2 / (R^3 - R^2)
+	 *  where cwnd / R is the number of Acks received per window of data
+	 *  (cf. RFC 4341, App. A). The problems are that
+	 *  - arsent counts other packets as well;
+	 *  - the comparison uses a formula different from RFC 4341;
+	 *  - computing a cubic/quadratic equation each time is too complicated.
+	 *  Hence a different algorithm is needed.