[TFRC]: New rx history code

Credit here goes to Gerrit Renker, that provided the initial implementation for
this new codebase.

I modified it just to try to make it closer to the existing API, renaming some
functions, add namespacing and fix one bug where the tfrc_rx_hist_alloc was not
freeing the allocated ring entries on the error path.

Original changeset comment from Gerrit:
      -----------
This provides a new, self-contained and generic RX history service for TFRC
based protocols.

Details:
 * new data structure, initialisation and cleanup routines;
 * allocation of dccp_rx_hist entries local to packet_history.c,
   as a service exported by the dccp_tfrc_lib module.
 * interface to automatically track highest-received seqno;
 * receiver-based RTT estimation (needed for instance by RFC 3448, 6.3.1);
 * a generic function to test for `data packets' as per  RFC 4340, sec. 7.7.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 9 deletions

diff --git a/net/dccp/ccids/ccid3.h b/net/dccp/ccids/ccid3.h
index b842a7dd99de..3c33dc670cf9 100644
--- a/net/dccp/ccids/ccid3.h
+++ b/net/dccp/ccids/ccid3.h
@@ -1,7 +1,8 @@
 /*
  *  net/dccp/ccids/ccid3.h
  *
- *  Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
+ *  Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
+ *  Copyright (c) 2007   The University of Aberdeen, Scotland, UK
  *
  *  An implementation of the DCCP protocol
  *
@@ -135,9 +136,7 @@ enum ccid3_hc_rx_states {
  *  @ccid3hcrx_x_recv  -  Receiver estimate of send rate (RFC 3448 4.3)
  *  @ccid3hcrx_rtt  -  Receiver estimate of rtt (non-standard)
  *  @ccid3hcrx_p  -  current loss event rate (RFC 3448 5.4)
- *  @ccid3hcrx_seqno_nonloss  -  Last received non-loss sequence number
- *  @ccid3hcrx_ccval_nonloss  -  Last received non-loss Window CCVal
- *  @ccid3hcrx_ccval_last_counter  -  Tracks window counter (RFC 4342, 8.1)
+ *  @ccid3hcrx_last_counter  -  Tracks window counter (RFC 4342, 8.1)
  *  @ccid3hcrx_state  -  receiver state, one of %ccid3_hc_rx_states
  *  @ccid3hcrx_bytes_recv  -  Total sum of DCCP payload bytes
  *  @ccid3hcrx_tstamp_last_feedback  -  Time at which last feedback was sent
@@ -152,14 +151,11 @@ struct ccid3_hc_rx_sock {
 #define ccid3hcrx_x_recv                ccid3hcrx_tfrc.tfrcrx_x_recv
 #define ccid3hcrx_rtt                   ccid3hcrx_tfrc.tfrcrx_rtt
 #define ccid3hcrx_p                     ccid3hcrx_tfrc.tfrcrx_p
-        u64                             ccid3hcrx_seqno_nonloss:48,
-                                        ccid3hcrx_ccval_nonloss:4,
-                                        ccid3hcrx_ccval_last_counter:4;
+        u8                              ccid3hcrx_last_counter:4;
         enum ccid3_hc_rx_states         ccid3hcrx_state:8;
         u32                             ccid3hcrx_bytes_recv;
         ktime_t                         ccid3hcrx_tstamp_last_feedback;
-        ktime_t                         ccid3hcrx_tstamp_last_ack;
-        struct list_head                ccid3hcrx_hist;
+        struct tfrc_rx_hist             ccid3hcrx_hist;
         struct list_head                ccid3hcrx_li_hist;
         u16                             ccid3hcrx_s;
         u32                             ccid3hcrx_pinv;