1/*-
2 * Copyright (C) 2016 Centre for Advanced Internet Architectures,
3 *  Swinburne University of Technology, Melbourne, Australia.
4 * Portions of this code were made possible in part by a gift from
5 *  The Comcast Innovation Fund.
6 * Implemented by Rasool Al-Saadi <ralsaadi@swin.edu.au>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30/*
31 * API for writing an Active Queue Management algorithm for Dummynet
32 *
33 * $FreeBSD$
34 */
35
36#ifndef _IP_DN_AQM_H
37#define _IP_DN_AQM_H
38
39#include <sys/ck.h>
40
41/* NOW is the current time in millisecond*/
42#define NOW ((V_dn_cfg.curr_time * tick) / 1000)
43
44#define AQM_UNOW (V_dn_cfg.curr_time * tick)
45#define AQM_TIME_1US ((aqm_time_t)(1))
46#define AQM_TIME_1MS ((aqm_time_t)(1000))
47#define AQM_TIME_1S ((aqm_time_t)(AQM_TIME_1MS * 1000))
48
49/* aqm time allows to store up to 4294 seconds */
50typedef uint32_t aqm_time_t;
51typedef int32_t aqm_stime_t;
52
53#define DN_AQM_MTAG_TS 55345
54
55/* Macro for variable bounding */
56#define BOUND_VAR(x,l,h)  ((x) > (h)? (h) : ((x) > (l)? (x) : (l)))
57
58/*
59 * Structure for holding data and function pointers that together represent a
60 * AQM algorithm.
61 */
62 struct dn_aqm {
63#define DN_AQM_NAME_MAX 50
64	char			name[DN_AQM_NAME_MAX];	/* name of AQM algorithm */
65	uint32_t	type;	/* AQM type number */
66
67	/* Methods implemented by AQM algorithm:
68	 *
69	 * enqueue	enqueue packet 'm' on queue 'q'.
70	 * 	Return 0 on success, 1 on drop.
71	 *
72	 * dequeue	dequeue a packet from queue 'q'.
73	 * 	Return a packet, NULL if no packet available.
74	 *
75	 * config	configure AQM algorithm
76	 * If required, this function should allocate space to store
77	 * the configurations and set 'fs->aqmcfg' to point to this space.
78	 * 'dn_extra_parms' includes array of parameters send
79	 * from ipfw userland command.
80	 * 	Return 0 on success, non-zero otherwise.
81	 *
82	 * deconfig	deconfigure AQM algorithm.
83	 * The allocated configuration memory space should be freed here.
84	 * 	Return 0 on success, non-zero otherwise.
85	 *
86	 * init	initialise AQM status variables of queue 'q'
87	 * This function is used to allocate space and init AQM status for a
88	 * queue and q->aqm_status to point to this space.
89	 * 	Return 0 on success, non-zero otherwise.
90	 *
91	 * cleanup	cleanup AQM status variables of queue 'q'
92	 * The allocated memory space for AQM status should be freed here.
93	 * 	Return 0 on success, non-zero otherwise.
94	 *
95	 * getconfig	retrieve AQM configurations
96	 * This function is used to return AQM parameters to userland
97	 * command. The function should fill 'dn_extra_parms' struct with
98	 * the AQM configurations using 'par' array.
99	 *
100	 */
101
102	int (*enqueue)(struct dn_queue *, struct mbuf *);
103	struct mbuf * (*dequeue)(struct dn_queue *);
104	int (*config)(struct dn_fsk *, struct dn_extra_parms *ep, int);
105	int (*deconfig)(struct dn_fsk *);
106	int (*init)(struct dn_queue *);
107	int (*cleanup)(struct dn_queue *);
108	int (*getconfig)(struct dn_fsk *, struct dn_extra_parms *);
109
110	int	ref_count; /*Number of queues instances in the system */
111	int	cfg_ref_count;	/*Number of AQM instances in the system */
112	CK_LIST_ENTRY(dn_aqm) next; /* Next AQM in the list */
113};
114
115/* Helper function to update queue and scheduler statistics.
116 * negative len + drop -> drop
117 * negative len -> dequeue
118 * positive len -> enqueue
119 * positive len + drop -> drop during enqueue
120 */
121__inline static void
122update_stats(struct dn_queue *q, int len, int drop)
123{
124	int inc = 0;
125	struct dn_flow *sni;
126	struct dn_flow *qni;
127
128	sni = &q->_si->ni;
129	qni = &q->ni;
130
131	if (len < 0)
132			inc = -1;
133	else if(len > 0)
134			inc = 1;
135
136	if (drop) {
137			qni->drops++;
138			sni->drops++;
139			V_dn_cfg.io_pkt_drop++;
140	} else {
141		/*update queue stats */
142		qni->length += inc;
143		qni->len_bytes += len;
144
145		/*update scheduler instance stats */
146		sni->length += inc;
147		sni->len_bytes += len;
148	}
149	/* tot_pkts  is updated in dn_enqueue function */
150}
151
152
153/* kernel module related function */
154int
155dn_aqm_modevent(module_t mod, int cmd, void *arg);
156
157#define DECLARE_DNAQM_MODULE(name, dnaqm)			\
158	static moduledata_t name##_mod = {			\
159		#name, dn_aqm_modevent, dnaqm		\
160	};							\
161	DECLARE_MODULE(name, name##_mod, 			\
162		SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 	\
163        MODULE_DEPEND(name, dummynet, 3, 3, 3)
164
165#endif
166