[linux-2.6-block.git] / net / dccp / ackvec.h

#ifndef _ACKVEC_H
#define _ACKVEC_H
/*
 *  net/dccp/ackvec.h
 *
 *  An implementation of the DCCP protocol
 *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
 *
 *	This program is free software; you can redistribute it and/or modify it
 *	under the terms of the GNU General Public License version 2 as
 *	published by the Free Software Foundation.
 */

#include <linux/compiler.h>
#include <linux/list.h>
#include <linux/time.h>
#include <linux/types.h>

/* Read about the ECN nonce to see why it is 253 */
#define DCCP_MAX_ACKVEC_LEN 253

#define DCCP_ACKVEC_STATE_RECEIVED	0
#define DCCP_ACKVEC_STATE_ECN_MARKED	(1 << 6)
#define DCCP_ACKVEC_STATE_NOT_RECEIVED	(3 << 6)

#define DCCP_ACKVEC_STATE_MASK		0xC0 /* 11000000 */
#define DCCP_ACKVEC_LEN_MASK		0x3F /* 00111111 */

/** struct dccp_ackvec - ack vector
 *
 * This data structure is the one defined in the DCCP draft
 * Appendix A.
 *
 * @dccpav_buf_head - circular buffer head
 * @dccpav_buf_tail - circular buffer tail
 * @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the
 * 		       buffer (i.e. %dccpav_buf_head)
 * @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
 * 		       by the buffer with State 0
 *
 * Additionally, the HC-Receiver must keep some information about the
 * Ack Vectors it has recently sent. For each packet sent carrying an
 * Ack Vector, it remembers four variables:
 *
 * @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement.
 * @dccpav_records - list of dccp_ackvec_record
 * @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
 *
 * @dccpav_time		- the time in usecs
 * @dccpav_buf - circular buffer of acknowledgeable packets
 */
struct dccp_ackvec {
	u64		dccpav_buf_ackno;
	struct list_head dccpav_records;
	struct timeval	dccpav_time;
	u8		dccpav_buf_head;
	u8		dccpav_buf_tail;
	u8		dccpav_ack_ptr;
	u8		dccpav_sent_len;
	u8		dccpav_vec_len;
	u8		dccpav_buf_nonce;
	u8		dccpav_ack_nonce;
	u8		dccpav_buf[DCCP_MAX_ACKVEC_LEN];
};

/** struct dccp_ackvec_record - ack vector record
 *
 * ACK vector record as defined in Appendix A of spec.
 *
 * The list is sorted by dccpavr_ack_seqno
 *
 * @dccpavr_node - node in dccpav_records
 * @dccpavr_ack_seqno - sequence number of the packet this record was sent on
 * @dccpavr_ack_ackno - sequence number being acknowledged
 * @dccpavr_ack_ptr - pointer into dccpav_buf where this record starts
 * @dccpavr_ack_nonce - dccpav_ack_nonce at the time this record was sent
 * @dccpavr_sent_len - lenght of the record in dccpav_buf
 */
struct dccp_ackvec_record {
	struct list_head dccpavr_node;
	u64		 dccpavr_ack_seqno;
	u64		 dccpavr_ack_ackno;
	u8		 dccpavr_ack_ptr;
	u8		 dccpavr_ack_nonce;
	u8		 dccpavr_sent_len;
};

struct sock;
struct sk_buff;

#ifdef CONFIG_IP_DCCP_ACKVEC
extern int dccp_ackvec_init(void);
extern void dccp_ackvec_exit(void);

extern struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority);
extern void dccp_ackvec_free(struct dccp_ackvec *av);

extern int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
			   const u64 ackno, const u8 state);

extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
					struct sock *sk, const u64 ackno);
extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
			     const u8 opt, const u8 *value, const u8 len);

extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);

static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
{
	return av->dccpav_sent_len != av->dccpav_vec_len;
}
#else /* CONFIG_IP_DCCP_ACKVEC */
static inline int dccp_ackvec_init(void)
{
	return 0;
}

static inline void dccp_ackvec_exit(void)
{
}

static inline struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
{
	return NULL;
}

static inline void dccp_ackvec_free(struct dccp_ackvec *av)
{
}

static inline int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
				  const u64 ackno, const u8 state)
{
	return -1;
}

static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
					       struct sock *sk, const u64 ackno)
{
}

static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
				    const u8 opt, const u8 *value, const u8 len)
{
	return -1;
}

static inline int dccp_insert_option_ackvec(const struct sock *sk,
					    const struct sk_buff *skb)
{
	return -1;
}

static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
{
	return 0;
}
#endif /* CONFIG_IP_DCCP_ACKVEC */
#endif /* _ACKVEC_H */
Commit	Line	Data
ae31c339 ACM	1	#ifndef _ACKVEC_H
	2	#define _ACKVEC_H
	3	/*
	4	* net/dccp/ackvec.h
	5	*
	6	* An implementation of the DCCP protocol
	7	* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
	13
ae31c339	14	#include <linux/compiler.h>
02bcf28c	15	#include <linux/list.h>
ae31c339 ACM	16	#include <linux/time.h>
	17	#include <linux/types.h>
	18
	19	/* Read about the ECN nonce to see why it is 253 */
	20	#define DCCP_MAX_ACKVEC_LEN 253
	21
	22	#define DCCP_ACKVEC_STATE_RECEIVED 0
	23	#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6)
	24	#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6)
	25
	26	#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */
	27	#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */
	28
	29	/** struct dccp_ackvec - ack vector
	30	*
	31	* This data structure is the one defined in the DCCP draft
	32	* Appendix A.
	33	*
	34	* @dccpav_buf_head - circular buffer head
	35	* @dccpav_buf_tail - circular buffer tail
	36	* @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the
	37	* buffer (i.e. %dccpav_buf_head)
	38	* @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
	39	* by the buffer with State 0
	40	*
	41	* Additionally, the HC-Receiver must keep some information about the
	42	* Ack Vectors it has recently sent. For each packet sent carrying an
	43	* Ack Vector, it remembers four variables:
	44	*
ae31c339	45	* @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement.
02bcf28c	46	* @dccpav_records - list of dccp_ackvec_record
ae31c339 ACM	47	* @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
ae31c339 ACM	48	*
ae31c339 ACM	49	* @dccpav_time - the time in usecs
	50	* @dccpav_buf - circular buffer of acknowledgeable packets
	51	*/
	52	struct dccp_ackvec {
ae31c339	53	u64 dccpav_buf_ackno;
02bcf28c	54	struct list_head dccpav_records;
ae31c339	55	struct timeval dccpav_time;
e4dfd449 ACM	56	u8 dccpav_buf_head;
	57	u8 dccpav_buf_tail;
	58	u8 dccpav_ack_ptr;
	59	u8 dccpav_sent_len;
	60	u8 dccpav_vec_len;
ae31c339 ACM	61	u8 dccpav_buf_nonce;
ae31c339 ACM	62	u8 dccpav_ack_nonce;
7400d781	63	u8 dccpav_buf[DCCP_MAX_ACKVEC_LEN];
ae31c339 ACM	64	};
ae31c339 ACM	65
02bcf28c AB	66	/** struct dccp_ackvec_record - ack vector record
	67	*
	68	* ACK vector record as defined in Appendix A of spec.
	69	*
	70	* The list is sorted by dccpavr_ack_seqno
	71	*
	72	* @dccpavr_node - node in dccpav_records
	73	* @dccpavr_ack_seqno - sequence number of the packet this record was sent on
	74	* @dccpavr_ack_ackno - sequence number being acknowledged
	75	* @dccpavr_ack_ptr - pointer into dccpav_buf where this record starts
	76	* @dccpavr_ack_nonce - dccpav_ack_nonce at the time this record was sent
	77	* @dccpavr_sent_len - lenght of the record in dccpav_buf
	78	*/
	79	struct dccp_ackvec_record {
	80	struct list_head dccpavr_node;
	81	u64 dccpavr_ack_seqno;
	82	u64 dccpavr_ack_ackno;
	83	u8 dccpavr_ack_ptr;
	84	u8 dccpavr_ack_nonce;
	85	u8 dccpavr_sent_len;
	86	};
	87
ae31c339 ACM	88	struct sock;
	89	struct sk_buff;
	90
	91	#ifdef CONFIG_IP_DCCP_ACKVEC
9b07ef5d ACM	92	extern int dccp_ackvec_init(void);
	93	extern void dccp_ackvec_exit(void);
	94
7400d781	95	extern struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority);
ae31c339 ACM	96	extern void dccp_ackvec_free(struct dccp_ackvec *av);
	97
	98	extern int dccp_ackvec_add(struct dccp_ackvec av, const struct sock sk,
	99	const u64 ackno, const u8 state);
	100
	101	extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
	102	struct sock *sk, const u64 ackno);
	103	extern int dccp_ackvec_parse(struct sock sk, const struct sk_buff skb,
	104	const u8 opt, const u8 *value, const u8 len);
	105
	106	extern int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb);
	107
	108	static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
	109	{
	110	return av->dccpav_sent_len != av->dccpav_vec_len;
	111	}
	112	#else /* CONFIG_IP_DCCP_ACKVEC */
9b07ef5d ACM	113	static inline int dccp_ackvec_init(void)
	114	{
	115	return 0;
	116	}
	117
	118	static inline void dccp_ackvec_exit(void)
	119	{
	120	}
	121
7400d781	122	static inline struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
ae31c339 ACM	123	{
	124	return NULL;
	125	}
	126
	127	static inline void dccp_ackvec_free(struct dccp_ackvec *av)
	128	{
	129	}
	130
	131	static inline int dccp_ackvec_add(struct dccp_ackvec av, const struct sock sk,
	132	const u64 ackno, const u8 state)
	133	{
	134	return -1;
	135	}
	136
	137	static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
	138	struct sock *sk, const u64 ackno)
	139	{
	140	}
	141
	142	static inline int dccp_ackvec_parse(struct sock sk, const struct sk_buff skb,
	143	const u8 opt, const u8 *value, const u8 len)
	144	{
	145	return -1;
	146	}
	147
	148	static inline int dccp_insert_option_ackvec(const struct sock *sk,
	149	const struct sk_buff *skb)
	150	{
	151	return -1;
	152	}
	153
	154	static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
	155	{
	156	return 0;
	157	}
	158	#endif /* CONFIG_IP_DCCP_ACKVEC */
	159	#endif /* _ACKVEC_H */