3 files changed, 89 insertions, 79 deletions

diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 849f5580efbd..4ff6ede0f07d 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -927,86 +927,11 @@ static void ccid3_hc_rx_detect_loss(struct sock *sk)
 {
 	struct dccp_sock *dp = dccp_sk(sk);
 	struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
-	struct dccp_rx_hist_entry *entry, *next, *packet;
-	struct dccp_rx_hist_entry *a_loss = NULL;
-	struct dccp_rx_hist_entry *b_loss = NULL;
-	u64 seq_loss = DCCP_MAX_SEQNO + 1;
-	u8 win_loss = 0;
-	u8 num_later = TFRC_RECV_NUM_LATE_LOSS;
+	u8 win_loss;
+	const u64 seq_loss = dccp_rx_hist_detect_loss(&hcrx->ccid3hcrx_hist,
+						      &hcrx->ccid3hcrx_li_hist,
+						      &win_loss);
 
-	list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist,
-				 dccphrx_node) {
-		if (num_later == 0) {
-			b_loss = entry;
-			break;
-		} else if (dccp_rx_hist_entry_data_packet(entry))
-			--num_later;
-	}
-
-	if (b_loss == NULL)
-		goto out_update_li;
-
-	num_later = 1;
-
-	list_for_each_entry_safe_continue(entry, next, &hcrx->ccid3hcrx_hist,
-					  dccphrx_node) {
-		if (num_later == 0) {
-			a_loss = entry;
-			break;
-		} else if (dccp_rx_hist_entry_data_packet(entry))
-			--num_later;
-	}
-
-	if (a_loss == NULL) {
-		if (list_empty(&hcrx->ccid3hcrx_li_hist)) {
-			/* no loss event have occured yet */
-			LIMIT_NETDEBUG("%s: TODO: find a lost data packet by "
-				       "comparing to initial seqno\n",
-				       dccp_role(sk));
-			goto out_update_li;
-		} else {
-			pr_info("%s: %s, sk=%p, ERROR! Less than 4 data "
-				"packets in history",
-				__FUNCTION__, dccp_role(sk), sk);
-			return;
-		}
-	}
-
-	/* Locate a lost data packet */
-	entry = packet = b_loss;
-	list_for_each_entry_safe_continue(entry, next, &hcrx->ccid3hcrx_hist,
-					  dccphrx_node) {
-		u64 delta = dccp_delta_seqno(entry->dccphrx_seqno,
-					     packet->dccphrx_seqno);
-
-		if (delta != 0) {
-			if (dccp_rx_hist_entry_data_packet(packet))
-				--delta;
-			/*
-			 * FIXME: check this, probably this % usage is because
-			 * in earlier drafts the ndp count was just 8 bits
-			 * long, but now it cam be up to 24 bits long.
-			 */
-#if 0
-			if (delta % DCCP_NDP_LIMIT !=
-			    (packet->dccphrx_ndp -
-			     entry->dccphrx_ndp) % DCCP_NDP_LIMIT)
-#endif
-			if (delta !=
-			     packet->dccphrx_ndp - entry->dccphrx_ndp) {
-				seq_loss = entry->dccphrx_seqno;
-				dccp_inc_seqno(&seq_loss);
-			}
-		}
-		packet = entry;
-		if (packet == a_loss)
-			break;
-	}
-
-	if (seq_loss != DCCP_MAX_SEQNO + 1)
-		win_loss = a_loss->dccphrx_ccval;
-
-out_update_li:
 	ccid3_hc_rx_update_li(sk, seq_loss, win_loss);
 }
 
diff --git a/net/dccp/ccids/lib/packet_history.c b/net/dccp/ccids/lib/packet_history.c
index e2576b45ac0b..d3f9d2053830 100644
--- a/net/dccp/ccids/lib/packet_history.c
+++ b/net/dccp/ccids/lib/packet_history.c
@@ -224,6 +224,88 @@ trim_history:
 
 EXPORT_SYMBOL_GPL(dccp_rx_hist_add_packet);
 
+u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
+			     struct list_head *li_list, u8 *win_loss)
+{
+	struct dccp_rx_hist_entry *entry, *next, *packet;
+	struct dccp_rx_hist_entry *a_loss = NULL;
+	struct dccp_rx_hist_entry *b_loss = NULL;
+	u64 seq_loss = DCCP_MAX_SEQNO + 1;
+	u8 num_later = TFRC_RECV_NUM_LATE_LOSS;
+
+	list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) {
+		if (num_later == 0) {
+			b_loss = entry;
+			break;
+		} else if (dccp_rx_hist_entry_data_packet(entry))
+			--num_later;
+	}
+
+	if (b_loss == NULL)
+		goto out;
+
+	num_later = 1;
+	list_for_each_entry_safe_continue(entry, next, rx_list, dccphrx_node) {
+		if (num_later == 0) {
+			a_loss = entry;
+			break;
+		} else if (dccp_rx_hist_entry_data_packet(entry))
+			--num_later;
+	}
+
+	if (a_loss == NULL) {
+		if (list_empty(li_list)) {
+			/* no loss event have occured yet */
+			LIMIT_NETDEBUG("%s: TODO: find a lost data packet by "
+				       "comparing to initial seqno\n",
+				       __FUNCTION__);
+			goto out;
+		} else {
+			LIMIT_NETDEBUG("%s: Less than 4 data pkts in history!",
+				       __FUNCTION__);
+			goto out;
+		}
+	}
+
+	/* Locate a lost data packet */
+	entry = packet = b_loss;
+	list_for_each_entry_safe_continue(entry, next, rx_list, dccphrx_node) {
+		u64 delta = dccp_delta_seqno(entry->dccphrx_seqno,
+					     packet->dccphrx_seqno);
+
+		if (delta != 0) {
+			if (dccp_rx_hist_entry_data_packet(packet))
+				--delta;
+			/*
+			 * FIXME: check this, probably this % usage is because
+			 * in earlier drafts the ndp count was just 8 bits
+			 * long, but now it cam be up to 24 bits long.
+			 */
+#if 0
+			if (delta % DCCP_NDP_LIMIT !=
+			    (packet->dccphrx_ndp -
+			     entry->dccphrx_ndp) % DCCP_NDP_LIMIT)
+#endif
+			if (delta != packet->dccphrx_ndp - entry->dccphrx_ndp) {
+				seq_loss = entry->dccphrx_seqno;
+				dccp_inc_seqno(&seq_loss);
+			}
+		}
+		packet = entry;
+		if (packet == a_loss)
+			break;
+	}
+out:
+	if (seq_loss != DCCP_MAX_SEQNO + 1)
+		*win_loss = a_loss->dccphrx_ccval;
+	else
+		*win_loss = 0; /* Paranoia */
+
+	return seq_loss;
+}
+
+EXPORT_SYMBOL_GPL(dccp_rx_hist_detect_loss);
+
 struct dccp_tx_hist *dccp_tx_hist_new(const char *name)
 {
 	struct dccp_tx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h
index ebfcb8e2c676..fb90a91aa93d 100644
--- a/net/dccp/ccids/lib/packet_history.h
+++ b/net/dccp/ccids/lib/packet_history.h
@@ -193,4 +193,7 @@ extern int dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
 				   struct list_head *li_list,
 				   struct dccp_rx_hist_entry *packet);
 
+extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
+				    struct list_head *li_list, u8 *win_loss);
+
 #endif /* _DCCP_PKT_HIST_ */