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
34#ifndef _IP_DN_AQM_H
35#define _IP_DN_AQM_H
36
37#include <sys/ck.h>
38
39/* NOW is the current time in millisecond*/
40#define NOW ((V_dn_cfg.curr_time * tick) / 1000)
41
42#define AQM_UNOW (V_dn_cfg.curr_time * tick)
43#define AQM_TIME_1US ((aqm_time_t)(1))
44#define AQM_TIME_1MS ((aqm_time_t)(1000))
45#define AQM_TIME_1S ((aqm_time_t)(AQM_TIME_1MS * 1000))
46
47/* aqm time allows to store up to 4294 seconds */
48typedef uint32_t aqm_time_t;
49typedef int32_t aqm_stime_t;
50
51#define DN_AQM_MTAG_TS 55345
52
53/* Macro for variable bounding */
54#define BOUND_VAR(x,l,h)  ((x) > (h)? (h) : ((x) > (l)? (x) : (l)))
55
56/*
57 * Structure for holding data and function pointers that together represent a
58 * AQM algorithm.
59 */
60 struct dn_aqm {
61#define DN_AQM_NAME_MAX 50
62	char			name[DN_AQM_NAME_MAX];	/* name of AQM algorithm */
63	uint32_t	type;	/* AQM type number */
64
65	/* Methods implemented by AQM algorithm:
66	 *
67	 * enqueue	enqueue packet 'm' on queue 'q'.
68	 * 	Return 0 on success, 1 on drop.
69	 *
70	 * dequeue	dequeue a packet from queue 'q'.
71	 * 	Return a packet, NULL if no packet available.
72	 *
73	 * config	configure AQM algorithm
74	 * If required, this function should allocate space to store
75	 * the configurations and set 'fs->aqmcfg' to point to this space.
76	 * 'dn_extra_parms' includes array of parameters send
77	 * from ipfw userland command.
78	 * 	Return 0 on success, non-zero otherwise.
79	 *
80	 * deconfig	deconfigure AQM algorithm.
81	 * The allocated configuration memory space should be freed here.
82	 * 	Return 0 on success, non-zero otherwise.
83	 *
84	 * init	initialise AQM status variables of queue 'q'
85	 * This function is used to allocate space and init AQM status for a
86	 * queue and q->aqm_status to point to this space.
87	 * 	Return 0 on success, non-zero otherwise.
88	 *
89	 * cleanup	cleanup AQM status variables of queue 'q'
90	 * The allocated memory space for AQM status should be freed here.
91	 * 	Return 0 on success, non-zero otherwise.
92	 *
93	 * getconfig	retrieve AQM configurations
94	 * This function is used to return AQM parameters to userland
95	 * command. The function should fill 'dn_extra_parms' struct with
96	 * the AQM configurations using 'par' array.
97	 *
98	 */
99
100	int (*enqueue)(struct dn_queue *, struct mbuf *);
101	struct mbuf * (*dequeue)(struct dn_queue *);
102	int (*config)(struct dn_fsk *, struct dn_extra_parms *ep, int);
103	int (*deconfig)(struct dn_fsk *);
104	int (*init)(struct dn_queue *);
105	int (*cleanup)(struct dn_queue *);
106	int (*getconfig)(struct dn_fsk *, struct dn_extra_parms *);
107
108	int	ref_count; /*Number of queues instances in the system */
109	int	cfg_ref_count;	/*Number of AQM instances in the system */
110	CK_LIST_ENTRY(dn_aqm) next; /* Next AQM in the list */
111};
112
113/* Helper function to update queue and scheduler statistics.
114 * negative len + drop -> drop
115 * negative len -> dequeue
116 * positive len -> enqueue
117 * positive len + drop -> drop during enqueue
118 */
119__inline static void
120update_stats(struct dn_queue *q, int len, int drop)
121{
122	int inc = 0;
123	struct dn_flow *sni;
124	struct dn_flow *qni;
125
126	sni = &q->_si->ni;
127	qni = &q->ni;
128
129	if (len < 0)
130			inc = -1;
131	else if(len > 0)
132			inc = 1;
133
134	if (drop) {
135			qni->drops++;
136			sni->drops++;
137			V_dn_cfg.io_pkt_drop++;
138	} else {
139		/*update queue stats */
140		qni->length += inc;
141		qni->len_bytes += len;
142
143		/*update scheduler instance stats */
144		sni->length += inc;
145		sni->len_bytes += len;
146	}
147	/* tot_pkts  is updated in dn_enqueue function */
148}
149
150/* kernel module related function */
151int
152dn_aqm_modevent(module_t mod, int cmd, void *arg);
153
154#define DECLARE_DNAQM_MODULE(name, dnaqm)			\
155	static moduledata_t name##_mod = {			\
156		#name, dn_aqm_modevent, dnaqm		\
157	};							\
158	DECLARE_MODULE(name, name##_mod, 			\
159		SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 	\
160        MODULE_DEPEND(name, dummynet, 3, 3, 3)
161
162#endif
163