1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2010 Riccardo Panicucci, Universita` di Pisa
5 * All rights reserved
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 /*
30 */
31 #ifdef _KERNEL
32 #include <sys/malloc.h>
33 #include <sys/socket.h>
34 #include <sys/socketvar.h>
35 #include <sys/kernel.h>
36 #include <sys/lock.h>
37 #include <sys/mbuf.h>
38 #include <sys/module.h>
39 #include <sys/rwlock.h>
40 #include <net/if.h> /* IFNAMSIZ */
41 #include <netinet/in.h>
42 #include <netinet/ip_var.h> /* ipfw_rule_ref */
43 #include <netinet/ip_fw.h> /* flow_id */
44 #include <netinet/ip_dummynet.h>
45 #include <netpfil/ipfw/ip_fw_private.h>
46 #include <netpfil/ipfw/dn_heap.h>
47 #include <netpfil/ipfw/ip_dn_private.h>
48 #ifdef NEW_AQM
49 #include <netpfil/ipfw/dn_aqm.h>
50 #endif
51 #include <netpfil/ipfw/dn_sched.h>
52 #else
53 #include <dn_test.h>
54 #endif
55
56 #define DN_SCHED_PRIO 5 //XXX
57
58 #if !defined(_KERNEL) || !defined(__linux__)
59 #define test_bit(ix, pData) ((*pData) & (1<<(ix)))
60 #define __set_bit(ix, pData) (*pData) |= (1<<(ix))
61 #define __clear_bit(ix, pData) (*pData) &= ~(1<<(ix))
62 #endif
63
64 #ifdef __MIPSEL__
65 #define __clear_bit(ix, pData) (*pData) &= ~(1<<(ix))
66 #endif
67
68 /* Size of the array of queues pointers. */
69 #define BITMAP_T unsigned long
70 #define MAXPRIO (sizeof(BITMAP_T) * 8)
71
72 /*
73 * The scheduler instance contains an array of pointers to queues,
74 * one for each priority, and a bitmap listing backlogged queues.
75 */
76 struct prio_si {
77 BITMAP_T bitmap; /* array bitmap */
78 struct dn_queue *q_array[MAXPRIO]; /* Array of queues pointers */
79 };
80
81 /*
82 * If a queue with the same priority is already backlogged, use
83 * that one instead of the queue passed as argument.
84 */
85 static int
prio_enqueue(struct dn_sch_inst * _si,struct dn_queue * q,struct mbuf * m)86 prio_enqueue(struct dn_sch_inst *_si, struct dn_queue *q, struct mbuf *m)
87 {
88 struct prio_si *si = (struct prio_si *)(_si + 1);
89 int prio = q->fs->fs.par[0];
90
91 if (test_bit(prio, &si->bitmap) == 0) {
92 /* No queue with this priority, insert */
93 __set_bit(prio, &si->bitmap);
94 si->q_array[prio] = q;
95 } else { /* use the existing queue */
96 q = si->q_array[prio];
97 }
98 if (dn_enqueue(q, m, 0))
99 return 1;
100 return 0;
101 }
102
103 /*
104 * Packets are dequeued only from the highest priority queue.
105 * The function ffs() return the lowest bit in the bitmap that rapresent
106 * the array index (-1) which contains the pointer to the highest priority
107 * queue.
108 * After the dequeue, if this queue become empty, it is index is removed
109 * from the bitmap.
110 * Scheduler is idle if the bitmap is empty
111 *
112 * NOTE: highest priority is 0, lowest is sched->max_prio_q
113 */
114 static struct mbuf *
prio_dequeue(struct dn_sch_inst * _si)115 prio_dequeue(struct dn_sch_inst *_si)
116 {
117 struct prio_si *si = (struct prio_si *)(_si + 1);
118 struct mbuf *m;
119 struct dn_queue *q;
120 int prio;
121
122 if (si->bitmap == 0) /* scheduler idle */
123 return NULL;
124
125 prio = ffs(si->bitmap) - 1;
126
127 /* Take the highest priority queue in the scheduler */
128 q = si->q_array[prio];
129 // assert(q)
130
131 m = dn_dequeue(q);
132 if (q->mq.head == NULL) {
133 /* Queue is now empty, remove from scheduler
134 * and mark it
135 */
136 si->q_array[prio] = NULL;
137 __clear_bit(prio, &si->bitmap);
138 }
139 return m;
140 }
141
142 static int
prio_new_sched(struct dn_sch_inst * _si)143 prio_new_sched(struct dn_sch_inst *_si)
144 {
145 struct prio_si *si = (struct prio_si *)(_si + 1);
146
147 bzero(si->q_array, sizeof(si->q_array));
148 si->bitmap = 0;
149
150 return 0;
151 }
152
153 static int
prio_new_fsk(struct dn_fsk * fs)154 prio_new_fsk(struct dn_fsk *fs)
155 {
156 /* Check if the prioritiy is between 0 and MAXPRIO-1 */
157 ipdn_bound_var(&fs->fs.par[0], 0, 0, MAXPRIO - 1, "PRIO priority");
158 return 0;
159 }
160
161 static int
prio_new_queue(struct dn_queue * q)162 prio_new_queue(struct dn_queue *q)
163 {
164 struct prio_si *si = (struct prio_si *)(q->_si + 1);
165 int prio = q->fs->fs.par[0];
166 struct dn_queue *oldq;
167
168 q->ni.oid.subtype = DN_SCHED_PRIO;
169
170 if (q->mq.head == NULL)
171 return 0;
172
173 /* Queue already full, must insert in the scheduler or append
174 * mbufs to existing queue. This partly duplicates prio_enqueue
175 */
176 if (test_bit(prio, &si->bitmap) == 0) {
177 /* No queue with this priority, insert */
178 __set_bit(prio, &si->bitmap);
179 si->q_array[prio] = q;
180 } else if ( (oldq = si->q_array[prio]) != q) {
181 /* must append to the existing queue.
182 * can simply append q->mq.head to q2->...
183 * and add the counters to those of q2
184 */
185 oldq->mq.tail->m_nextpkt = q->mq.head;
186 oldq->mq.tail = q->mq.tail;
187 oldq->ni.length += q->ni.length;
188 q->ni.length = 0;
189 oldq->ni.len_bytes += q->ni.len_bytes;
190 q->ni.len_bytes = 0;
191 q->mq.tail = q->mq.head = NULL;
192 }
193 return 0;
194 }
195
196 static int
prio_free_queue(struct dn_queue * q)197 prio_free_queue(struct dn_queue *q)
198 {
199 int prio = q->fs->fs.par[0];
200 struct prio_si *si = (struct prio_si *)(q->_si + 1);
201
202 if (si->q_array[prio] == q) {
203 si->q_array[prio] = NULL;
204 __clear_bit(prio, &si->bitmap);
205 }
206 return 0;
207 }
208
209 static struct dn_alg prio_desc = {
210 _SI( .type = ) DN_SCHED_PRIO,
211 _SI( .name = ) "PRIO",
212 _SI( .flags = ) DN_MULTIQUEUE,
213
214 /* we need extra space in the si and the queue */
215 _SI( .schk_datalen = ) 0,
216 _SI( .si_datalen = ) sizeof(struct prio_si),
217 _SI( .q_datalen = ) 0,
218
219 _SI( .enqueue = ) prio_enqueue,
220 _SI( .dequeue = ) prio_dequeue,
221
222 _SI( .config = ) NULL,
223 _SI( .destroy = ) NULL,
224 _SI( .new_sched = ) prio_new_sched,
225 _SI( .free_sched = ) NULL,
226
227 _SI( .new_fsk = ) prio_new_fsk,
228 _SI( .free_fsk = ) NULL,
229
230 _SI( .new_queue = ) prio_new_queue,
231 _SI( .free_queue = ) prio_free_queue,
232 #ifdef NEW_AQM
233 _SI( .getconfig = ) NULL,
234 #endif
235 };
236
237 DECLARE_DNSCHED_MODULE(dn_prio, &prio_desc);
238