dccp ccid-2: move rfc 3390 function into header file

This moves CCID-2's initial window function into the header file, since several
parts throughout the CCID-2 code need to call it (CCID-2 still uses RFC 3390).

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Leandro Melo de Sales <leandro@ic.ufal.br>

1 files changed, 9 insertions, 0 deletions

diff --git a/net/dccp/ccids/ccid2.h b/net/dccp/ccids/ccid2.h
index e9985dafc2c..f17460a8fe7 100644
--- a/net/dccp/ccids/ccid2.h
+++ b/net/dccp/ccids/ccid2.h
@@ -88,6 +88,15 @@ static inline bool ccid2_cwnd_network_limited(struct ccid2_hc_tx_sock *hc)
 	return hc->tx_pipe >= hc->tx_cwnd;
 }
 
+/*
+ * Convert RFC 3390 larger initial window into an equivalent number of packets.
+ * This is based on the numbers specified in RFC 5681, 3.1.
+ */
+static inline u32 rfc3390_bytes_to_packets(const u32 smss)
+{
+	return smss <= 1095 ? 4 : (smss > 2190 ? 2 : 3);
+}
+
 struct ccid2_hc_rx_sock {
 	int	rx_data;
 };