/*      $NetBSD: altq_red.h,v 1.5 2006/10/12 19:59:08 peter Exp $       */
/*      $KAME: altq_red.h,v 1.8 2003/07/10 12:07:49 kjc Exp $   */

/*
* Copyright (C) 1997-2003
*      Sony Computer Science Laboratories Inc.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#ifndef _ALTQ_ALTQ_RED_H_
#define _ALTQ_ALTQ_RED_H_

#include <altq/altq_classq.h>

#ifdef ALTQ3_COMPAT
struct red_interface {
       char    red_ifname[IFNAMSIZ];
};

struct red_stats {
       struct red_interface iface;
       int q_len;
       int q_avg;

       struct pktcntr  xmit_cnt;
       struct pktcntr  drop_cnt;
       u_int           drop_forced;
       u_int           drop_unforced;
       u_int           marked_packets;

       /* static red parameters */
       int q_limit;
       int weight;
       int inv_pmax;
       int th_min;
       int th_max;

       /* flowvalve related stuff */
       u_int fv_flows;
       u_int fv_pass;
       u_int fv_predrop;
       u_int fv_alloc;
       u_int fv_escape;
};

struct red_conf {
       struct red_interface iface;
       int red_weight;         /* weight for EWMA */
       int red_inv_pmax;       /* inverse of max drop probability */
       int red_thmin;          /* red min threshold */
       int red_thmax;          /* red max threshold */
       int red_limit;          /* max queue length */
       int red_pkttime;        /* average packet time in usec */
       int red_flags;          /* see below */
};
#endif /* ALTQ3_COMPAT */

/* red flags */
#define REDF_ECN4       0x01    /* use packet marking for IPv4 packets */
#define REDF_ECN6       0x02    /* use packet marking for IPv6 packets */
#define REDF_ECN        (REDF_ECN4 | REDF_ECN6)
#define REDF_FLOWVALVE  0x04    /* use flowvalve (aka penalty-box) */

/*
* simpler versions of red parameters and statistics used by other
* disciplines (e.g., CBQ)
*/
struct redparams {
       int th_min;             /* red min threshold */
       int th_max;             /* red max threshold */
       int inv_pmax;           /* inverse of max drop probability */
};

struct redstats {
       int             q_avg;
       struct pktcntr  xmit_cnt;
       struct pktcntr  drop_cnt;
       u_int           drop_forced;
       u_int           drop_unforced;
       u_int           marked_packets;
};

#ifdef ALTQ3_COMPAT
/*
* IOCTLs for RED
*/
#define RED_IF_ATTACH           _IOW('Q', 1, struct red_interface)
#define RED_IF_DETACH           _IOW('Q', 2, struct red_interface)
#define RED_ENABLE              _IOW('Q', 3, struct red_interface)
#define RED_DISABLE             _IOW('Q', 4, struct red_interface)
#define RED_CONFIG              _IOWR('Q', 6, struct red_conf)
#define RED_GETSTATS            _IOWR('Q', 12, struct red_stats)
#define RED_SETDEFAULTS         _IOW('Q', 30, struct redparams)
#endif /* ALTQ3_COMPAT */

#ifdef _KERNEL

#ifdef ALTQ3_COMPAT
struct flowvalve;
#endif

/* weight table structure for idle time calibration */
struct wtab {
       struct wtab     *w_next;
       int              w_weight;
       int              w_param_max;
       int              w_refcount;
       int32_t          w_tab[32];
};

typedef struct red {
       int             red_pkttime;    /* average packet time in micro sec
                                          used for idle calibration */
       int             red_flags;      /* red flags */

       /* red parameters */
       int             red_weight;     /* weight for EWMA */
       int             red_inv_pmax;   /* inverse of max drop probability */
       int             red_thmin;      /* red min threshold */
       int             red_thmax;      /* red max threshold */

       /* variables for internal use */
       int             red_wshift;     /* log(red_weight) */
       int             red_thmin_s;    /* th_min scaled by avgshift */
       int             red_thmax_s;    /* th_max scaled by avgshift */
       int             red_probd;      /* drop probability denominator */

       int             red_avg;        /* queue len avg scaled by avgshift */
       int             red_count;      /* packet count since last dropped/
                                          marked packet */
       int             red_idle;       /* queue was empty */
       int             red_old;        /* avg is above th_min */
       struct wtab     *red_wtab;      /* weight table */
       struct timeval   red_last;      /* time when the queue becomes idle */

#ifdef ALTQ3_COMPAT
       struct flowvalve *red_flowvalve;        /* flowvalve state */
#endif

       struct {
               struct pktcntr  xmit_cnt;
               struct pktcntr  drop_cnt;
               u_int           drop_forced;
               u_int           drop_unforced;
               u_int           marked_packets;
       } red_stats;
} red_t;

#ifdef ALTQ3_COMPAT
typedef struct red_queue {
       struct red_queue *rq_next;      /* next red_state in the list */
       struct ifaltq *rq_ifq;          /* backpointer to ifaltq */

       class_queue_t *rq_q;

       red_t *rq_red;
} red_queue_t;
#endif /* ALTQ3_COMPAT */

/* red drop types */
#define DTYPE_NODROP    0       /* no drop */
#define DTYPE_FORCED    1       /* a "forced" drop */
#define DTYPE_EARLY     2       /* an "unforced" (early) drop */

extern red_t            *red_alloc(int, int, int, int, int, int);
extern void              red_destroy(red_t *);
extern void              red_getstats(red_t *, struct redstats *);
extern int               red_addq(red_t *, class_queue_t *, struct mbuf *,
                            struct altq_pktattr *);
extern struct mbuf      *red_getq(red_t *, class_queue_t *);
extern int               drop_early(int, int, int);
extern int               mark_ecn(struct mbuf *, struct altq_pktattr *, int);
extern struct wtab      *wtab_alloc(int);
extern int               wtab_destroy(struct wtab *);
extern int32_t           pow_w(struct wtab *, int);

#endif /* _KERNEL */

#endif /* _ALTQ_ALTQ_RED_H_ */