include/net/sctp/tsnmap.h - kernel/msm-5.4 - Gitiles

 /* SCTP kernel reference Implementation
  * (C) Copyright IBM Corp. 2001, 2004
  * Copyright (c) 1999-2000 Cisco, Inc.
  * Copyright (c) 1999-2001 Motorola, Inc.
  * Copyright (c) 2001 Intel 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>
  *   Sridhar Samudrala     <sri@us.ibm.com>
  *
  * 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;

 	/* Record duplicate TSNs here.  We clear this after
 	 * every SACK.  Store up to SCTP_MAX_DUP_TSNS worth of
 	 * information.
 	 */
 	__be32 dup_tsns[SCTP_MAX_DUP_TSNS];
 	__u16 num_dup_tsns;

 	/* Record gap ack block information here.  */
 	struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];

 	int malloced;

 	__u8 raw_map[0];
 };

 struct sctp_tsnmap_iter {
 	__u32 start;
 };

 /* 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);

 /* Mark this TSN and all lower as seen. */
 void sctp_tsnmap_skip(struct sctp_tsnmap *map, __u32 tsn);

 /* Retrieve the Cumulative TSN ACK Point.  */
 static inline __u32 sctp_tsnmap_get_ctsn(const struct sctp_tsnmap *map)
 {
 	return map->cumulative_tsn_ack_point;
 }

 /* Retrieve the highest TSN we've seen.  */
 static inline __u32 sctp_tsnmap_get_max_tsn_seen(const struct sctp_tsnmap *map)
 {
 	return map->max_tsn_seen;
 }

 /* 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 __be32 *sctp_tsnmap_get_dups(struct sctp_tsnmap *map)
 {
 	map->num_dup_tsns = 0;
 	return map->dup_tsns;
 }

 /* How many gap ack blocks do we have recorded? */
 __u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map);

 /* Refresh the count on pending data. */
 __u16 sctp_tsnmap_pending(struct sctp_tsnmap *map);

 /* Return pointer to gap ack blocks as needed by SACK. */
 static inline struct sctp_gap_ack_block *sctp_tsnmap_get_gabs(struct sctp_tsnmap *map)
 {
 	return map->gabs;
 }

 /* Is there a gap in the TSN map?  */
 static inline int sctp_tsnmap_has_gap(const struct sctp_tsnmap *map)
 {
 	int has_gap;

 	has_gap = (map->cumulative_tsn_ack_point != map->max_tsn_seen);
 	return has_gap;
 }

 /* 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 *);

 #endif /* __sctp_tsnmap_h__ */
	/* SCTP kernel reference Implementation
	* (C) Copyright IBM Corp. 2001, 2004
	* Copyright (c) 1999-2000 Cisco, Inc.
	* Copyright (c) 1999-2001 Motorola, Inc.
	* Copyright (c) 2001 Intel 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>
	* Sridhar Samudrala <sri@us.ibm.com>
	*
	* 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;

	/* Record duplicate TSNs here. We clear this after
	* every SACK. Store up to SCTP_MAX_DUP_TSNS worth of
	* information.
	*/
	__be32 dup_tsns[SCTP_MAX_DUP_TSNS];
	__u16 num_dup_tsns;

	/* Record gap ack block information here. */
	struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];

	int malloced;

	__u8 raw_map[0];
	};

	struct sctp_tsnmap_iter {
	__u32 start;
	};

	/* 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);

	/* Mark this TSN and all lower as seen. */
	void sctp_tsnmap_skip(struct sctp_tsnmap *map, __u32 tsn);

	/* Retrieve the Cumulative TSN ACK Point. */
	static inline __u32 sctp_tsnmap_get_ctsn(const struct sctp_tsnmap *map)
	{
	return map->cumulative_tsn_ack_point;
	}

	/* Retrieve the highest TSN we've seen. */
	static inline __u32 sctp_tsnmap_get_max_tsn_seen(const struct sctp_tsnmap *map)
	{
	return map->max_tsn_seen;
	}

	/* 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 __be32 sctp_tsnmap_get_dups(struct sctp_tsnmap map)
	{
	map->num_dup_tsns = 0;
	return map->dup_tsns;
	}

	/* How many gap ack blocks do we have recorded? */
	__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map);

	/* Refresh the count on pending data. */
	__u16 sctp_tsnmap_pending(struct sctp_tsnmap *map);

	/* Return pointer to gap ack blocks as needed by SACK. */
	static inline struct sctp_gap_ack_block sctp_tsnmap_get_gabs(struct sctp_tsnmap map)
	{
	return map->gabs;
	}

	/* Is there a gap in the TSN map? */
	static inline int sctp_tsnmap_has_gap(const struct sctp_tsnmap *map)
	{
	int has_gap;

	has_gap = (map->cumulative_tsn_ack_point != map->max_tsn_seen);
	return has_gap;
	}

	/* 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 *);

	#endif /* __sctp_tsnmap_h__ */