patch-2.4.23 linux-2.4.23/include/net/sctp/tsnmap.h

• Lines: 187
• Date: 2003-11-28 10:26:21.000000000 -0800
• Orig file: linux-2.4.22/include/net/sctp/tsnmap.h
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.22/include/net/sctp/tsnmap.h linux-2.4.23/include/net/sctp/tsnmap.h
@@ -0,0 +1,186 @@
+/* SCTP kernel reference Implementation Copyright (C) 1999-2001
+ * Cisco, Motorola, Intel, and International Business Machines Corp.
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * These are the definitions needed for the tsnmap type.  The tsnmap is used
+ * to track out of order TSNs received.
+ *
+ * The SCTP reference implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP reference implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <lksctp-developers@lists.sourceforge.net>
+ *
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by:
+ *   Jon Grimm             <jgrimm@us.ibm.com>
+ *   La Monte H.P. Yarroll <piggy@acm.org>
+ *   Karl Knutson          <karl@athena.chicago.il.us>
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+#include <net/sctp/constants.h>
+
+#ifndef __sctp_tsnmap_h__
+#define __sctp_tsnmap_h__
+
+/* RFC 2960 12.2 Parameters necessary per association (i.e. the TCB)
+ * Mapping  An array of bits or bytes indicating which out of
+ * Array    order TSN's have been received (relative to the
+ *          Last Rcvd TSN). If no gaps exist, i.e. no out of
+ *          order packets have been received, this array
+ *          will be set to all zero. This structure may be
+ *          in the form of a circular buffer or bit array.
+ */
+struct sctp_tsnmap {
+	/* This array counts the number of chunks with each TSN.
+	 * It points at one of the two buffers with which we will
+	 * ping-pong between.
+	 */
+	__u8 *tsn_map;
+
+	/* This marks the tsn which overflows the tsn_map, when the
+	 * cumulative ack point reaches this point we know we can switch
+	 * maps (tsn_map and overflow_map swap).
+	 */
+	__u32 overflow_tsn;
+
+	/* This is the overflow array for tsn_map.
+	 * It points at one of the other ping-pong buffers.
+	 */
+	__u8 *overflow_map;
+
+	/* This is the TSN at tsn_map[0].  */
+	__u32 base_tsn;
+
+	/* Last Rcvd   : This is the last TSN received in
+	 * TSN	       : sequence. This value is set initially by
+	 *             : taking the peer's Initial TSN, received in
+	 *             : the INIT or INIT ACK chunk, and subtracting
+	 *             : one from it.
+	 *
+	 * Throughout most of the specification this is called the
+	 * "Cumulative TSN ACK Point".  In this case, we
+	 * ignore the advice in 12.2 in favour of the term
+	 * used in the bulk of the text.
+	 */
+	__u32 cumulative_tsn_ack_point;
+
+	/* This is the minimum number of TSNs we can track.  This corresponds
+	 * to the size of tsn_map.   Note: the overflow_map allows us to
+	 * potentially track more than this quantity.
+	 */
+	__u16 len;
+
+	/* This is the highest TSN we've marked.  */
+	__u32 max_tsn_seen;
+
+	/* Data chunks pending receipt. used by SCTP_STATUS sockopt */
+	__u16 pending_data;
+
+	/* We record duplicate TSNs here.  We clear this after
+	 * every SACK.  Store up to SCTP_MAX_DUP_TSNS worth of
+	 * information.
+	 */
+	__u32 dup_tsns[SCTP_MAX_DUP_TSNS];
+	__u16 num_dup_tsns;
+
+	int malloced;
+
+	__u8 raw_map[0];
+};
+
+struct sctp_tsnmap_iter {
+	__u32 start;
+};
+
+/* Create a new tsnmap.  */
+struct sctp_tsnmap *sctp_tsnmap_new(__u16 len, __u32 init_tsn, int gfp);
+
+/* Dispose of a tsnmap.  */
+void sctp_tsnmap_free(struct sctp_tsnmap *);
+
+/* This macro assists in creation of external storage for variable length
+ * internal buffers.  We double allocate so the overflow map works.
+ */
+#define sctp_tsnmap_storage_size(count) (sizeof(__u8) * (count) * 2)
+
+/* Initialize a block of memory as a tsnmap.  */
+struct sctp_tsnmap *sctp_tsnmap_init(struct sctp_tsnmap *, __u16 len,
+				     __u32 initial_tsn);
+
+/* Test the tracking state of this TSN.
+ * Returns:
+ *   0 if the TSN has not yet been seen
+ *  >0 if the TSN has been seen (duplicate)
+ *  <0 if the TSN is invalid (too large to track)
+ */
+int sctp_tsnmap_check(const struct sctp_tsnmap *, __u32 tsn);
+
+/* Mark this TSN as seen.  */
+void sctp_tsnmap_mark(struct sctp_tsnmap *, __u32 tsn);
+
+/* Retrieve the Cumulative TSN ACK Point.  */
+__u32 sctp_tsnmap_get_ctsn(const struct sctp_tsnmap *);
+
+/* Retrieve the highest TSN we've seen.  */
+__u32 sctp_tsnmap_get_max_tsn_seen(const struct sctp_tsnmap *);
+
+/* How many Duplicate TSNs are stored? */
+static inline __u16 sctp_tsnmap_num_dups(struct sctp_tsnmap *map)
+{
+	return map->num_dup_tsns;
+}
+
+/* Return pointer to duplicate tsn array as needed by SACK. */
+static inline __u32 *sctp_tsnmap_get_dups(struct sctp_tsnmap *map)
+{
+	map->num_dup_tsns = 0;
+	return map->dup_tsns;
+}
+
+/* Mark a duplicate TSN.  Note:  limit the storage of duplicate TSN
+ * information.
+ */
+static inline void sctp_tsnmap_mark_dup(struct sctp_tsnmap *map, __u32 tsn)
+{
+	if (map->num_dup_tsns < SCTP_MAX_DUP_TSNS)
+		map->dup_tsns[map->num_dup_tsns++] = htonl(tsn);
+}
+
+/* Renege a TSN that was seen.  */
+void sctp_tsnmap_renege(struct sctp_tsnmap *, __u32 tsn);
+
+/* Is there a gap in the TSN map? */
+int sctp_tsnmap_has_gap(const struct sctp_tsnmap *);
+
+/* Initialize a gap ack block interator from user-provided memory.  */
+void sctp_tsnmap_iter_init(const struct sctp_tsnmap *,
+			   struct sctp_tsnmap_iter *);
+
+/* Get the next gap ack blocks.  We return 0 if there are no more
+ * gap ack blocks.
+ */
+int sctp_tsnmap_next_gap_ack(const struct sctp_tsnmap *,
+	struct sctp_tsnmap_iter *,__u16 *start, __u16 *end);
+
+#endif /* __sctp_tsnmap_h__ */